受賞国：アメリカ合衆国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：アメリカ合衆国

Outstanding contributions to sol-gel science and technology through broad and productive scholarship; by achievements in commercial and industrial applications of sol-gel science and technology; and/or by outstanding service to the sol-gel community that has been sustained over an entire career

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials Research Society Symposium Proceedings  

In various crosslinking systems containing metal oxides, organo-siloxane polymers and pure hydrocarbons, monolithic materials with hierarchical well-defined macropores and controlled mesopores have been synthesized. Synthetic progress in alkoxy-derived macroporous silica lead to the preparation of long-range ordered mesoporous skeletons in well-defined macroporous framework. Alkylene-bridged silicon alkoxides can also be prepared into similarly hierarchical porous structures with broadened variations in framework morphology. Macro-mesoporous alkoxy-derived pure titania and zirconia have been prepared using hydrochloric acid - mediated processes. Compared with those prepared from colloidal dispersions, alkoxy-derived macroporous titania exhibited much higher mechanical strength. Titania monolith is a promising candidate as a separation medium to discriminate phosphorylated compounds in a liquid chromatography mode. Pure alumina macroporous monolith has been first synthesized from aluminum salt using propylene glycol as a proton scavenger to thrust the solution pH from acidic into neutral conditions. Alumina-based complex oxides such as garnets and spinels can also be prepared in pure phases. Polymerization and phase separation in organic crosslinker system was also controlled to obtain well-defined co-continuous macro-frameworks instead of those composed of aggregated particles. These examples demonstrate the versatility of using phase-separation in gelling systems to obtain well-defined macroporous structures. © 2007 Materials Research Society.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials Research Society Symposium Proceedings  

Transparent organic-inorganic hybrid aerogels and aerogel-like xerogels have been prepared from methyltrimethoxysilane (MTMS) respectively by supercritical drying (SCD) and ambient pressure drying (APD). The new aerogels and xerogels significantly deform without collapsing on uniaxial compression and almost fully relax when unloaded. This elastic behavior, termed as "spring-back", allows APD without noticeable shrinkage and cracking. The flexible network composed of lower cross-linking density (up to three bonds per every silicon atom) compared to silica gels (up to four bonds) and repulsion between hydrophobic methyl groups bonded to every silicon atom largely contributes to the pronounced deformability and relaxing, respectively. Lower surface silanol group density also plays a crucial role for the "spring-back" behavior. © 2009 Materials Research Society.

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Preprints, Japan  

This work was aimed to development of continuous-flow living radical polymerization in a silica-gel column, "Chromolith", focusing its separation function by combination of surface chemical absorption and size-exclusion via uniquely shaped mesopores, Thus, living radical copolymerization of two monomers with different polarities, methyl methacrylate (MMA) and 2(dimethylamino)ethyl methacrylate (DMAEMA) was performed with a catalyst [2; Ru(Ind)Cl(PPh3)2] coupled with an initiator (1). Copolymers were continuously produced, and molecular weight distributions were narrower than that in the corresponding batch process.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials Research Society Symposium Proceedings  

Macroporous crosslinked polymer gels have been prepared via TEMPO-mediated living radical polymerization of divinylbenzene (DVB) in a solvent with a counter polymer. Incorporating a counter polymer, poly(dimethylsiloxane) (PDMS), induced macroscopic spinodal-type phase separation during the course of polymerization of DVB while suppressing the segregation of DVB-derived particles from the solution by living polymerization. Well-defined macroporous morphologies comprising continuous DVB-derived skeletons have thus obtained. Macropore volume and diameter were independently controlled by altering the concentrations of PDMS and the solvent. Since the present polymer gels are prepared using only the multifunctional "crosslinker", mechanical durability against bending and compression was found to be as high as inorganic ceramics with similar morphologies and porosities. © 2007 Materials Research Society.

DOI： 10.1557/proc-0947-a03-27

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials Research Society Symposium Proceedings  

Organic-Inorganic hybrid gels with hierarchical well-defined macropores and supramolecularly templated mesopores with long-range orders have been synthesized in the systems of bridged poly(silsesquioxane) systems. Nonionic surfactants such as poly(ethyleneglycol)-poly(propyleneglycol)- poly(ethyleneglycol) triblock copolymers, EOPOEOs, were found to be effective both in inducing the phase separation to give macroporous morphology and in templating the mesopores with narrow size distribution. The number of methylene units in the bridge, changed from 1 to 6 in the present experiments, affected both the phase separation tendency and template strength. In the system containing 1,2-bis(trimethoxysilyl)ethane, 2D-hexagonal arrangement of mesopores have been prepared in the gel skeleton comprising the well-defined continuous macroporous network with an aid of micelle-stabilizing agent. © 2005 Materials Research Society.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials Research Society Symposium Proceedings  

Monolithic pure silica gels with hierarchical macro-mesoporous structure have been synthesized via spontaneous sol-gel process from silicon alkoxidc using a structure-directing agent and a micelle-swelling agent. Monolithic body with well-defined co-continuous macropores is a result of concurrent phase separation and sol-gel transition induced by the polymerization reaction, whereas the mesopores are templated by the cooperative self-assembly of inorganic species, a structure-directing agent and a micelle-swelling agent. The following removal of surfactants by heat-treatment gives silica gels with hierarchical and fully accessible pores in discrete size ranges of micrometers and nanometers. The highly ordered 2D-hexagonal arrays of mesopores have been confirmed by X-ray diffraction measurements and FE-SEM observations. Furthermore, by further additions of the micelle-swelling agent, the mesostructural transition from well-ordered 2D-hexagonal arrays to mesostructured cellular foams (MCF) have been induced accompanied by minor modifications of the micrometer-range structure. © 2005 Materials Research Society.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Preprints, Japan  

A catalyst corresponding to Ru(Ind)Cl(PPh3)2 was covalently supported onto a mesopore and silica-gel (Chromolith™) to construct a "size-exclusion column reactor" in which "physical control" of polymer molecular weight is expected by the retention-time difference of each mobile substrate according to its size exclusion (Scheme 2). With Ru(II)-catalyzed living radical polymerization continuously performed in this column, better reaction control is expected by not only the supported catalyst but by this column separation (Fig. 1). The Ru-bearing column 5 (powder form) in fact induced living radical polymerization of methyl methacrylate with initiator 6 and an additive (n-Bu2NH) in toluene at 80°C (Fig. 2). Continuous flow polymerization in the column reactor will be discussed and compared with those in batch systems.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Thermal insulating materials are of importance for efficient and effective use of heat energy. Porous organic foams are widely employed for this purpose owing to their low thermal conductivity and mass productivity at low cost. However, the poor thermal stability of organic polymers limits their availability within a low temperature range (typically, < 150 °C). In this paper, we demonstrate the one-pot sol–gel synthesis of porous poly(amic acid) (PAA) xerogels and their conversion to porous polyimide (PI) monoliths by thermal imidization. The PAA networks crosslinked with either aromatic or aliphatic triamine and the bicontinuous porous morphology tailored via spinodal decomposition allow the evaporative drying at ambient pressure to obtain low-density PAA xerogels without significant shrinkage. The aromatic crosslinker yields the porous PI monoliths with higher porosity and flexible feature as compared with those prepared with the aliphatic triamine. On the other hand, the porous PI monolith based on the aliphatic crosslinker possesses slightly higher thermal stability owing to the stiffer mechanical property. The durability test results verify the porous PI thermal insulators are available in air at up to ~450 °C for a short period and up to ~350 °C for a long term. [Figure not available: see fulltext.]

DOI： 10.1007/s10971-022-05843-8

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その他リンク： https://link.springer.com/article/10.1007/s10971-022-05843-8/fulltext.html

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

DOI： 10.1007/s10971-022-05955-1

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Applied Polymer Materials  

A way to utilize eggshells is desired because most of the eggshell waste is disposed of in landfills. Despite eggshells having attractive features such as a thermodynamically stable porous crystalline structure, their effective utilization as a functional material has yet to be demonstrated. Herein, we developed an alkali-stable column packing material for reversed-phase preparative high-performance liquid chromatography (HPLC) based on eggshells. Nanocrystals and biopolymers present on eggshell powder were removed by surface treatment with buffered ethylenediaminetetraacetic acid (EDTA) and sodium hypochlorite solutions, resulting in bare calcium carbonate with a uniform porous surface. The obtained particles were modified with poly(maleic acid-alt-1-octadecene) (PMAcO) having hydrophobic alkyl chains and anionic carboxylate groups. The prepared PMAcO-modified eggshell-based material was applied to an HPLC column, and its performance is evaluated. The column succeeded in the separation of alkylbenzenes, steroids, and diastereomers. It was also used for the separation of basic tricyclic antidepressants in an alkaline mobile phase, showing excellent retention capacity and alkali stability. This study demonstrates the potential of eggshell utilization, providing not only a practical stationary phase for HPLC but also a solution for recycling calcium carbonate-based biomineral waste.

DOI： 10.1021/acsapm.2c00866

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Applied Materials and Interfaces  

Internal spacing of electrodes is a key point for controlling electron-transfer (ET)-related phenomena. However, their disordered porous structures often prevent the observation of microscopic effects. It hampers the development of modern electrochemical theories. The development of model porous electrodes therefore provides an ideal platform to discover intriguing fundamental principles of electrode processes. We developed a new synthetic strategy for all-oxide monolithic ruthenium dioxide (RuO2)/antimony-doped tin oxide (ATO) electrodes with a controlled hierarchically porous structure and oxide-oxide heterojunction. The use of the obtained RuO2/ATO electrodes as model electrodes suppressed influences related to different mass diffusion efficiencies between electrodes with heterojunctions of different types. Then, we showed unconventional oxide-oxide heterojunction effects, improving reversible Li+-coupled electron-transfer properties using model electrodes constituted of various nanostructured (nano-) RuO2 on porous ATO. In addition to the superior electrochemical properties of the nano-RuO2/ATO heterojunction, the quasi-two-dimensional (2D) RuO2/ATO heterojunction led to improved specific capacity at a high rate and longer cycle life. We anticipate that this oxide-oxide heterojunction effect and developed all-oxide model porous electrodes can provide a path to develop advanced reversible energy storage devices.

DOI： 10.1021/acsami.2c06297

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Ceramic Society  

Porous nonoxide ceramics have exhibited impressive progress in terms of synthesis and applications over the past few decades because of their unique characteristics distinguished from the oxide counterparts. From the synthetic aspect, the preceramic polymer route, where nonoxide ceramics such as carbides and nitrides are produced from molecular precursors, offers exceptional opportunities to elaborate and control the material shape as well as the micro- and nanostructures in concert with various techniques. This review presents monolithic ceramic materials based on various reduced phases bearing hierarchical porosity with a focus on those obtained from macroporous preceramic monoliths prepared via the one-pot sol–gel process accompanied by spinodal decomposition. Here, we highlight two classes of preceramic inorganic–organic hybrid gels: organometallic crosslinked polymers based on poly(silsesquioxane)s and nonorganometallic hybrid networks related to Ti without Ti–C bonds. The polymer-to-ceramic conversion processes are discussed with concern for the crystal transition behaviors and the variation of pore properties in different length scales upon heating. In addition, although out of the preceramic polymer category, some examples of inorganic–organic nanocomposite gels with a carbonizable polymer and/or urea for yielding porous metal carbides and nitrides in a monolithic form are introduced as well, which provides extended versatility toward a variety of transition metal systems.

DOI： 10.1111/jace.18130

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：New Journal of Chemistry  

Hierarchically porous tin oxide monoliths have been prepared for the first time from a low-cost tin(iv) chloride precursor through an epoxide-mediated sol-gel process in an aprotic solvent N,N-dimethylformamide. Phase separation is induced in the presence of poly(propylene glycol) in the course of polymerization triggered by an acid scavenger, propylene oxide, leading to macroporous tin-based oxyhydroxide monoliths. The resultant macropores are confirmed to be controlled in the size range of 0.9-2.9 μm. Both the post-gelation solvothermal treatment in 2-propanol and calcination in air gave rise to crystallinity and mesoporosity (2.4-103 nm in size with BET surface area up to 261 m2 g-1), and hierarchically porous tin oxide monoliths have been obtained for the first time. The monoliths are demonstrated as a catalyst for the esterification of valeric acid and methanol. This journal is

DOI： 10.1039/d1nj03307g

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials Advances  

We have developed a general synthetic strategy to control macroporous structures and material shapes of metal-organic framework (MOF) gels via a sol-gel based structural control process. A series of 1,3,5-benzene tricarboxylic acid (BTC) based MOF gels, Cr-BTC and Zr-BTC, have been chosen as a proof of concept.

DOI： 10.1039/d0ma01009j

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Clinical and Experimental Nephrology  

Background: Pathological findings in Alport syndrome frequently show mesangial proliferation and sometimes incidental IgA deposition, in addition to unique glomerular basement membrane (GBM) changes including thin basement membrane and/or lamellation. However, similar GBM abnormalities are also often observed in IgA nephropathy. Both diseases are also known to show hematuria, proteinuria, and sometimes macrohematuria when associated with viral infection. Therefore, it can be difficult to make a differential diagnosis, even based on clinical and pathological findings. Some recent articles demonstrated that galactose-deficient IgA1 (Gd-IgA1)-specific monoclonal antibody (KM55) could potentially enable incidental IgA deposition to be distinguished from IgA nephropathy. Methods: We performed comprehensive gene screening and glomerular Gd-IgA1 and type IV collagen α5 chain immunostaining for five cases with both IgA deposition and GBM changes to confirm that Gd-IgA1 can help to distinguish these two diseases. Results: Four of the cases were genetically diagnosed with Alport syndrome (Cases 1–4) and one was IgA nephropathy with massive GBM changes, which had a negative gene test result (Case 5). In Cases 1–4, glomerular Gd-IgA1 deposition was not detected, although there was positivity for IgA in the mesangial area. In Case 5, glomerular Gd-IgA1 deposition was observed. Conclusion: Gd-IgA1 expression analysis could clearly differentiate these two disorders. This approach can be applied to identify these two diseases showing identical clinical and pathological findings.

DOI： 10.1007/s10157-021-02054-3

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Advances in Mathematics  

The Cauchy problem for the Zakharov system in the energy-critical dimension d=4 is considered. We prove that global well-posedness holds in the full (non-radial) energy space for any initial data with energy and wave mass below the ground state threshold. The result is based on a Strichartz estimate for the Schrödinger equation with a potential. More precisely, a Strichartz estimate is proved to hold uniformly for any potential solving the free wave equation with mass below the ground state constraint. The key new ingredient is a bilinear (adjoint) Fourier restriction estimate for solutions of the inhomogeneous Schrödinger equation with forcing in dual endpoint Strichartz spaces.

DOI： 10.1016/j.aim.2021.107746

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Lymphatic Research and Biology  

Background: Manual lymph drainage (MLD) is one of the common treatments for breast cancer-related lymphedema (BCRL). Although the primary goal of MLD is to drain the excessive fluid accumulated in the affected upper limb and trunk to an area of the body that drains usually, the use of MLD is decided based on swelling and subjective symptoms, without assessing whether there is fluid accumulated in the affected region. The purpose of this study was to examine truncal fluid distribution in a sample of BCRL patients and investigate any correlation between such fluid distribution and swelling or subjective symptoms. Methods and Results: An observational study was conducted with 13 women who had unilateral, upper extremity BCRL. Fluid distribution was evaluated by using two magnetic resonance imaging (MRI) sequences: half-Fourier acquisition single-shot turbo spin echo and three-dimensional double-echo steady-state. The presence of swelling was determined by lymphedema therapists, and subjective symptoms were measured by using a visual analog scale. On MRI, no participants had any free water signals in the trunk. However, seven had swelling and all 13 had some kind of subjective symptoms on the affected side of their trunk. Conclusions: These results suggest that swelling and subjective symptoms do not correlate with the presence of truncal fluid. For such cases, a different approach than MLD may be needed to address truncal swelling and related subjective symptoms. Checking for the presence of fluid in the truncal region may help MLD be used more appropriately.

DOI： 10.1089/lrb.2020.0075

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Ceramic Society  

Cobalt manganite-based hierarchically porous monoliths (HPMs) with three-dimensionally (3D) interconnected macropores and open nanopores have been prepared via the sol–gel process accompanied by phase separation. The controlled hydrolysis and polycondensation of the brominated metal alkoxides, which are generated from an incomplete reaction between epichlorohydrin and MBr2 (M = Co and Mn) in N,N-dimethylformamide (DMF), form a monolithic gel based on the two divalent metal cations. The dual-polymer strategy using polyvinylpyrrolidone (PVP) and poly(ethylene oxide) (PEO) effectively induces the spinodal decomposition, where PVP and PEO are preferentially distributed to the gel phase and fluid phase, respectively, resulting in a porous gel characterized by the co-continuous structure. The effects of DMF and PVP on the porous morphology derived from the phase separation have been systematically studied. Calcination of the as-dried gels allows for the crystallization into the spinel phase yielding hierarchically porous CoMn2O4 monoliths, which have been examined in detail by the structural and compositional analyses.

DOI： 10.1111/jace.17662

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials Advances  

We report a new synthetic strategy for melamine-formaldehyde (MF) monoliths with controlled hierarchical porosity toward metal-ion scavengers. The obtained MF monoliths possessed micro-, meso- and macroporosity, which allowed efficient adsorption performance of precious metal ions in water. Applications such as recovery/removal of metal ions are expected.

DOI： 10.1039/d1ma00034a

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Physical Chemistry C  

Porous architecture is key in the nonaqueous lithium-oxygen (Li-O2) electrode process, which is attracting huge interest because of its application in reversible energy storage with high theoretical energy density. However, it is still challenging to understand the optimal porous structure to obtain high reversibility of the reaction. One main reason is because of instability and undefined porous structures of standard electrodes consisting of carbonaceous materials, and this issue hinders from unveiling the fundamental mechanism in the complicated electrode process. Here, we developed a new synthetic strategy to design monolithic electrodes of pure metallic nickel with controlled bimodal porous structures. The present work aims to investigate the fundamental effects of the bimodal macroporous structure in the Li-O2 electrode process under carbon-/binder-free stable model electrodes. As the result, we found that, depending on the multiscale structural configurations, the bimodal macroporous structure gave significant influences to key properties, such as the efficiency of redox-mediators, discharge overpotential, and cycling life. This work indicates that the rational design of stable and conductive porous materials is one of the promising approaches to investigate highly complicated electrochemical reactions in porous electrodes and suggest new guidelines for further development of hierarchically structured electrodes toward advanced electrochemical systems.

DOI： 10.1021/acs.jpcc.0c10446

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：National Science Review  

Hierarchically porous monoliths based on copper (Cu), cobalt (Co) and manganese (Mn) oxides with three-dimensionally (3D) interconnected macropores and open nanopores were prepared using metal bromides as precursors via a sol-gel process accompanied by phase separation. The difficulty of gelation for low-valence metal cation was overcome by introducing a highly electronegative Br atom near to the metal atom to control the rates of hydrolysis and polycondensation. The 3D interconnected macropores were obtained using appropriate polymers to induce phase separation. The domain sizes of macropores and skeletons can be controlled by reaction parameters such as concentration and/or average molecular weight of polymers, and the amount of hydrochloric acid. The crystalline metal oxide monoliths with their 3D interconnected macroporous structure preserved were obtained after heat treatment in air.

DOI： 10.1093/nsr/nwaa103

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Hierarchically porous materials with large pores in the micrometer range and small pores in the nanometer range, where the large pores facilitate mass transport and the small pores supply numerous active sites, show superiority to materials with unimodal pores in the fields of separation and adsorption. Among all the methods used to prepare hierarchically porous monoliths (HPMs), the sol–gel process accompanied by spinodal decomposition (or phase separation) shows its advantages such as facile method, no template, precise structural control, good reproducibility, and availability for various kinds of materials. This review focuses on the specific process to prepare various types of HPMs including silica, metal oxides, metal phosphates, and metal–organic hybrids, via the sol–gel process accompanied by spinodal decomposition. The HPMs composed of organic polymer and their carbonized derivatives prepared by polymerization-induced phase separation are also covered in this review as an example of similar morphological formation in purely organic crosslinking reactions. This review directs the most attention to the preparation of monolithic gels (sol–gel process) and the control of macroporous structure (phase separation). [Figure not available: see fulltext.].

DOI： 10.1007/s10971-020-05370-4

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

A wide-range control over multimodal pore systems in porous monoliths is a key technology for developing functional materials, as the favorable pore structures in different length scales are required to be tailored depending on their application fields. In the alkoxy-derived sol–gel systems of silica and organosilicates, the synthetic methodology of meso- and macroporous monoliths with tunable pore properties has been developed by combining the supramolecular self-assembly of a Pluronic surfactant and polymerization-induced phase-separation techniques. This strategy has been applied to the sol–gel process of phenolic resins, giving rise to the hierarchically porous polymer gels with ordered mesoporosity and the corresponding carbon monoliths after carbonization. However, the controllable size range has been limited so far. This study has explored the relationship between the starting composition and the bimodal pore properties in further detail aiming at a better control of pore properties in phenolic resins. The enlargement of mesopore size has been achieved, yet associated with broadening the mesopore size distribution and coarsening the macropore morphology, resulting in the particle aggregates. The systematical investigation also reveals that the addition of KCl can improve the micelle arrangement in macroframework and provide the narrower mesopore size distribution. [Figure not available: see fulltext.]

DOI： 10.1007/s10971-020-05236-9

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：New Journal of Chemistry  

A superhydrophobic mesoporous silica material loaded with on-site formed small Ag nanoparticles has been prepared via surface modification with octadecylsilane (C18H37SiH3) and subsequent reduction of silver acetate with residual hydrido groups on-site. The resultant material shows excellent antibacterial activity for Gram-negative E. coli and Gram-positive S. aureus. This journal is

DOI： 10.1039/d0nj02502j

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Materials Chemistry B  

We report novel superhydrophobic highly flexible composites based on a doubly cross-linked (DCL) aerogel and carbon nanotubes (CNTs) for strain/pressure sensing. The DCL aerogel/CNT composite is prepared by radical polymerization of vinylmethyldimethoxysilane and vinyldimethylmethoxysilane, respectively, followed by hydrolytic co-polycondensation of the obtained polyvinylmethyldimethoxysilane and polyvinyldimethylmethoxysilane, combined with the incorporation of CNTs. Benefiting from the flexible methyl-rich DCL structure of the aerogel and conductive CNTs, the resultant DCL aerogel/CNT composite combines superhydrophobicity, high compressibility, high bendability, high elasticity, and strain- and pressure-sensitive conductivity. We demonstrate that the composite can be applied as a high-performance strain/pressure sensor for the detection of arterial pulse waves and joint bending with high sensitivity and high durability against humidity.

DOI： 10.1039/c9tb02953b

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

We report new polyorganosiloxane aerogels with superhydrophobicity, high elasticity, and high bendability based on polyvinyl-poly(dimethylsiloxane) (PVPDMS)/polymethylsilsesquioxane (PMSQ). They are synthesized by a radical polymerization/co-polycondensation strategy that involves radical polymerization of vinyldimethylmethoxysilane to obtain chainlike polyvinyldimethylmethoxysilane (PVDMMS) polymers followed by hydrolytic co-polycondensation of PVDMMS polymers and methyltrimethoxysilane combined with ambient pressure drying without any post-gelation modifications. The resultant PVPDMS/PMSQ aerogels exhibit a highly tunable triple-network structure consisting of flexible inter-cross-linked hydrocarbon polymers, poly(dimethylsiloxane), and PMSQ. The aerogels with a low content of PVPDMS exhibit small pore sizes (2-80 nm), good transparency, high surface areas, and thermal superinsulation (λ = 0.0148 W m-1 K-1), while those with a high content of PVPDMS exhibit large pore sizes (100 nm-3 μm) and excellent selective absorption for organic liquids. In addition, incorporation of graphene oxide (GO) in PVPDMS/PMSQ aerogels can afford highly flexible PVPDMS/PMSQ/GO composite aerogels, which show efficient separation of three-component water/oil/dye mixtures. These aerogels are promising in the practical applications of thermal insulation, absorption/adsorption, and separation.

DOI： 10.1021/acs.chemmater.9b04877

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Applied Nano Materials  

Aerogels have many unique properties such as low density and low thermal conductivity, and, in particular, transparent silica aerogels are attractive for thermal insulating windows. Practical applications of silica aerogels, however, have been limited because of their low mechanical strength, and it is still challenging to synthesize transparent and mechanically strong aerogels. Here, we report colorless transparent melamine-formaldehyde (MF) aerogels prepared via a nonaqueous synthetic strategy. The obtained transparent MF aerogel with a density of 0.18 g cm-3 shows significantly higher mechanical strength and a lower thermal conductivity of ca. 13 mW m-1 K-1 compared to conventional silica aerogels with similar density.

DOI： 10.1021/acsanm.9b02275

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie - International Edition  

We present a two-step template-free approach toward monolithic materials with controlled trimodal porous structures with macro-, meso-, and micropores. Our method relies on two ordering processes in discrete length scales: 1) Spontaneous formation of macroporous structures in monolithic materials by the sol–gel process through the short-range ordered self-assembly of metal–organic frameworks (MOFs), and 2) reorganization of the framework structures in a mediator solution. The Zr-terephthalate-based MOF (UiO-66-NH2) was adopted as a proof of concept. The self-assembly-induced phase separation process offered interconnected macropores with diameters ranging from 0.9 to 1.8 μm. The subsequent reorganization process converted the microporous structure from low crystalline framework to crystalline UiO-66. The resultant mesopore size within the skeletons was controlled in the range from 9 to 21 nm. This approach provides a novel way of designing spaces from nano- to micrometer scale in network-forming materials.

DOI： 10.1002/anie.201911499

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

DOI： 10.1002/ange.201911499

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials and Design  

Resilient, fire-retardant and mechanically strong polyimide-polyvinylpolymethylsiloxane (PI-PVPMS) composite aerogels have been prepared via stepwise chemical liquid deposition (SCLD). The synthesis is based on the formation of PI-PVPMS crosslinked network structure with (3-aminopropyl)trimethoxysilane (APTMS) as a coupling agent to provide reactive sites on the backbone. We successfully realize the PI in-situ growth on the whole super-flexible PVPMS gel skeleton with this simple method. The effect of APTMS amount and deposition time on the properties of final samples is deeply investigated. The resultant PI-PVPMS composite aerogels show excellent mechanical and thermal properties. They can support at least 10,000 times of their own weight and can recover 20% from a 60% of compressive strain, with an elastic modulus of 32 MPa. For thermal performance, they can maintain their structural integrity after being subjected to the alcohol lamp outer flame of around 650 °C for 30 min. These results together with the simple synthesis process demonstrate the potential for construction materials using PI-PVPMS composite aerogels. Furthermore, the SCLD synthesis method could also be applied to prepare other composite aerogels, especially for those containing complex polymer.

DOI： 10.1016/j.matdes.2019.108096

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Applied Materials and Interfaces  

Aerogels have attracted great interest for their unique properties, but their mechanical brittleness and poor functionality highly limit their practical applications. Herein, we report unprecedented superelastic multifunctional aminosilane-crosslinked reduced graphene oxide (AC-rGO) aerogels that are prepared via a facile and scalable strategy involving simultaneous crosslinking and reducing of graphene oxide nanosheets with different kinds of aminosilanes via C-N coupling and hydrolytic polycondensation reactions. It is found that 3-aminopropyl(diethoxy)methylsilane (APDEMS) is the better choice to enhance hydrophobicity, elasticity, and other properties of the resulting aerogels compared with (3-aminopropyl)triethoxysilane. One APDEMS molecule plays three roles as a crosslinker, a reductant, and a hydrophobizing agent. An outstanding combination of high surface area, ultralow density, superhydrophobicity, supercompressibility, superelasticity, low thermal conductivity, ultrahigh absorption capacity for organic liquids, efficient three-component separation, and strain/pressure sensing has been achieved in a single APDEMS-crosslinked rGO aerogel for the first time. In addition, a flexible, highly sensitive, and moisture-resistant AC-rGO aerogel-based strain/pressure-sensing array for the effective detection of strain (0-80%)/pressure (10 Pa to 10 kPa) distributions and object shapes has been demonstrated.

DOI： 10.1021/acsami.9b16746

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PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Langmuir  

Free-standing electrodes, which are free from additives (binders and conductive agents) and even current collectors, are useful in terms of both application research and fundamental study. Here, we demonstrate the preparation of binder-free monolithic carbon electrodes embracing Si nanoparticles in their well-defined porous scaffolds via the one-pot sol-gel reaction followed by carbonization. The free-standing electrodes with a thickness of 150 μm work out as a high-areal-density anode for Li-ion batteries, delivering up to ca. 7 mA h cm-2. As the Si content increases, the capacity decay on cycling becomes pronounced, which is likely to associate with the fracturing and pulverization of Si nanoparticles even with the size smaller than 100 nm after long-term cycles. The thermogravimetry-mass spectrometry profile of the cycled electrode corroborates the successive electrolyte decomposition to grow solid electrolyte interphase (SEI) mainly composed of lithium alkylcarbonates, polymeric species, and LiF, rendering the electrode mass nearly double of its original state after 200 cycles. The elemental mapping analysis reveals that LiF is generated inhomogeneously in the monolithic electrodes unlike the other SEI components, resulting in the concentration gradient depending on the distance from a Li counter electrode.

DOI： 10.1021/acs.langmuir.9b02085

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Chemistry  

Aerogels exhibit unique properties, but their practical applications have been restricted by low mechanical strength and costly supercritical drying; it remains difficult to obtain highly flexible aerogels with good thermal insulation and absorption by ambient pressure drying (APD). Here, we report novel highly flexible aerogels based on the polyvinylpolymethylsiloxane (PVPMS)/polyvinyltrimethylsilane (PVTMS) co-network, which consists of inter-cross-linked hydrocarbon and siloxane polymers with dangling trimethylsilyl groups, and its nanocomposite with polypyrrole (PPy). The PVPMS/PVTMS copolymer aerogels are facilely synthesized by a consecutive radical co-polymerization and hydrolytic polycondensation strategy from two monomers vinylmethyldimethoxysilane and trimethylvinylsilane without additional cross-linkers, followed by APD without any post-gelation modification. The PPy nanocomposite aerogels are synthesized by an in situ oxidation polymerization of pyrrole in the copolymer aerogel networks, followed by APD. The resulting aerogels consist of meso-to macro-scaled pore structures with tunable skeleton and pore sizes with variable cross-linking density and bulk density. In addition, these aerogels show good hydrophobicity and high flexibility in both compression and bending. Moreover, different functionalities such as excellent thermal insulation, oil-water separation, and pressure sensing can be imparted, allowing them to exhibit potential applications in thermal insulation, separation, and sensing.

DOI： 10.1039/c9py00751b

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

Recently, many efforts have been made to develop various smart sensors. However, achieving flexible multifunctional sensors combining excellent sensing of temperature, strain, and pressure with a single material is still challenging. Here, we report unprecedented superhydrophobic ultraflexible reduced graphene oxide (rGO)/polyorganosiloxane aerogels and high-performance multifunctional temperature/strain/pressure sensors based on these aerogels. GO nanosheets are first cross-linked and reduced with (3-aminopropyl)triethoxysilane (APTES) to obtain APTES-modified rGO aerogels, which are then further covalently cross-linked with polyvinylmethyldimethoxysilane polymers and vinylmethyldimethoxysilane via copolycondensation to afford rGO/polyorganosiloxane aerogels. The resulting aerogels exhibit a coralline-like triple-network nanostructure consisting of rGO nanosheets, polyvinyl-poly(methylsiloxane), and poly(vinylmethylsiloxane) that are cross-linked with each other. The aerogels combine superhydrophobicity, high compressibility, high bendability, superelasticity, excellent machinability, and temperature-, strain-, and pressure-sensitive conductivity, which is a combination not observed with traditional materials. In addition, an rGO/polyorganosiloxane aerogel-based flexible multifunctional sensing array combining sensing of temperature (20-100 °C), strain (in the wide range of 0.1-80%), and pressure (in the wide range of 10 Pa to 110 kPa) with high sensitivity and high durability against compression, bending, and humidity has been demonstrated for the first time.

DOI： 10.1021/acs.chemmater.9b02437

Scopus

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：New Journal of Chemistry  

A facile method for the preparation of zinc oxide with three-dimensionally (3D) interconnected macropores has been developed. The Zn-based monolithic gel was obtained using citric acid (CA) as a structure supporter via an epoxide-mediated sol-gel method accompanied by phase separation. The size of the macropores could be controlled by the ratio of methanol to propylene oxide in the starting solution. The Zn-based gel was heat-treated in air with the purpose of removing the organic components and crystallizing the ZnO, finally resulting in pure ZnO (purity >90%, with negligible carbon content) with 3D interconnected macropores and an open nanoscale network. The influence of the starting solvent composition on the Zn-based gel morphologies has been examined and discussed based on the chemical compatibility of the Zn-CA complex with other components.

DOI： 10.1039/c9nj02373a

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Abstract: Utilizing the spontaneous wetting of oligomeric silica-phase via phase-separation onto a solid surface in a confined dimension, sub-micrometer thick mesoporous layers have been coated on the surface of nonporous skeletons of preformed macroporous silica gels. The size and volume of mesopores within the layers could be controlled by subsequent aging conditions similarly to those reported for fully porous monolithic silica. Comparison of HPLC efficiencies of these novel type monolithic gels, core-shell silica monoliths, with those of a conventional silica monolith revealed that the retention factor per unit surface area became larger for core-shell silica monoliths. The increase in dynamic accessibility of analyte molecules to the mesopores well explain the improved retention factors in core-shell silica monoliths. [Figure not available: see fulltext.]

DOI： 10.1007/s10971-018-4889-2

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Abstract: Here, we overview the developments in the past decade made on organic–inorganic hybrid aerogels and xerogels based on silicone (polyorganosiloxanes) through persistent works by the authors to increase the mechanical strength and flexibility and add functionality. Polymethylsilsesquioxane (PMSQ, CH3SiO3/2) has been found to show unusual strength and flexibility against compression, and their bending properties can also be improved by several strategies. Silicone-based networks with organic bridges between inorganic moieties are also beneficial for these improvements. In particular, organic bridges with a higher fraction and more extended length have been found to allow higher durability against large deformations. In addition, functional groups such as vinyl, chloromethyl, and amino can readily be introduced by starting from organoalkoxysilanes with these functional substituents (e.g., FG−Si(OR)3 or (RO)3Si−FG−Si(OR)3, where FG shows an organic substituent containing functional groups and R is typically methyl or ethyl), and other functional groups such as carboxyl can be introduced by post-gelation modifications on the pre-installed FG in the network. Possibilities in applications such as thermal insulators, photoluminescent media, and photocatalysts are also discussed. [Figure not available: see fulltext.].

DOI： 10.1007/s10971-018-4804-x

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Hierarchically porous magnesium oxide, MgO, monoliths with a well-defined continuous macroporous structure have been synthesized via the sol–gel route accompanied by phase separation. Magnesium chloride hexahydrate was used as a precursor, and propylene oxide was used as an acid scavenger to raise the pH of a reaction solution homogenously. In order to obtain a crack-free monolith after heating in air, poly(vinylpyrrolidone), PVP, was employed as a scaffold of the skeleton as well as a phase separation controller to form the continuous macropores with higher homogeneity. Due to the moderate hydrogen-bonding interaction with magnesium hydroxide, PVP reinforces the gel network essentially composed of fine grained magnesium hydroxide. Even after the removal of all organic components by calcination, the porous gel samples maintained their monolithic form. On the other hand, an additional incorporation of 1,3,5-benzenetricarboxylic acid, H3BTC, was found to be effective in suppressing the oriented growth of the micrometer-sized crystalline phase. The polycrystalline MgO monoliths with specific surface area of 185, 64, and 48 m2 g−1 were prepared after heating at 400, 500, and 600 °C in air, respectively. [Figure not available: see fulltext.].

DOI： 10.1007/s10971-018-4682-2

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/s41598-018-34220-1

PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Abstract: Hierarchically porous spinel-type binary metal oxide MgAl2O4 with cocontinuous skeletons and interconnected macropores has been synthesized by a facile sol–gel method accompanied by phase separation, in which poly (ethylene oxide) (PEO) works as phase separation inducer to form micrometer-scale phase-separated macrochannels at the same time of sol–gel transition. The obtained xerogels exhibit in the form of a monolith with well-defined macropores and cocontinuous dense skeletons by adjusting the amount of PEO. The xerogel and those heat-treated at or below 600 °C are amorphous, and heat-treatment at or above 700 °C allows the precipitation of complete crystalline MgAl2O4 spinel with a macropore size of 0.7–0.9 μm, a porosity of 60–70%, and a BET surface area of 40–80 m2 g−1, without spoiling the macrostructure of monoliths. Three anionic dyes and two cationic dyes are selected as targeted adsorbates to investigate the selective adsorption ability of a hierarchically porous MgAl2O4 spinel. The resultant MgAl2O4 spinel shows a high affinity and adsorption rate toward anionic dyes Congo Red, Methyl Orange, and Methyl Blue. The maximum adsorption capacity of MgAl2O4 spinel toward these three anionic dyes are 2721.6 mg g−1 for Congo Red, 2469.7 mg g−1 for Methyl Orange, and 6771.9 mg g−1 for Methyl Blue, respectively. [Figure not available: see fulltext.]

DOI： 10.1007/s10971-018-4781-0

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nature  

Galaxies in the early Universe that are bright at submillimetre wavelengths (submillimetre-bright galaxies) are forming stars at a rate roughly 1,000 times higher than the Milky Way. A large fraction of the new stars form in the central kiloparsec of the galaxy1–3, a region that is comparable in size to the massive, quiescent galaxies found at the peak of cosmic star-formation history4 and the cores of present-day giant elliptical galaxies. The physical and kinematic properties inside these compact starburst cores are poorly understood because probing them at relevant spatial scales requires extremely high angular resolution. Here we report observations with a linear resolution of 550 parsecs of gas and dust in an unlensed, submillimetre-bright galaxy at a redshift of z = 4.3, when the Universe was less than two billion years old. We resolve the spatial and kinematic structure of the molecular gas inside the heavily dust-obscured core and show that the underlying gas disk is clumpy and rotationally supported (that is, its rotation velocity is larger than the velocity dispersion). Our analysis of the molecular gas mass per unit area suggests that the starburst disk is gravitationally unstable, which implies that the self-gravity of the gas is stronger than the differential rotation of the disk and the internal pressure due to stellar-radiation feedback. As a result of the gravitational instability in the disk, the molecular gas would be consumed by star formation on a timescale of 100 million years, which is comparable to gas depletion times in merging starburst galaxies5.

DOI： 10.1038/s41586-018-0443-1

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie - International Edition  

Aerogels are porous materials but show poor mechanical properties and limited functionality, which significantly restrict their practical applications. Preparation of highly bendable and processable aerogels with multifunctionality remains a challenge. Herein we report unprecedented superflexible aerogels based on polyvinylpolydimethylsiloxane (PVPDMS) networks, PVPDMS/polyvinylpolymethylsiloxane (PVPMS) copolymer networks, and PVPDMS/PVPMS/graphene nanocomposites by a facile radical polymerization/hydrolytic polycondensation strategy and ambient pressure drying or freeze drying. The aerogels have a doubly cross-linked organic–inorganic network structure consisting of flexible polydimethylsiloxanes and hydrocarbon chains with tunable cross-linking density, tunable pore size and bulk density. They have a high hydrophobicity and superflexibility and combine selective absorption, efficient separation of oil and water, thermal superinsulation, and strain sensing.

DOI： 10.1002/anie.201804559

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

DOI： 10.1002/ange.201804559

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Inorganic Chemistry Frontiers  

Simple post-treatments of the porous titania monolith in varied concentrations of phosphoric acid solution provide a series of monolithic titanium phosphates (TiPs) with a hierarchically porous structure together with an exquisite macropore surface. Depending on the reaction conditions, platy crystallites composed of either Ti2O3(H2PO4)2·2H2O, Ti(HPO4)2·H2O (α-TiP), or Ti2O(PO4)2·2H2O (π-TiP) are generated on the macropore skeleton via a dissolution and reprecipitation process, which forms distinct wrinkled surface morphologies. In addition, the treatments effectively suppress the shrinkage during drying, leading to lower bulk density. Post-calcination in air yields porous titanium pyrophosphates preserving the intricate porous architecture in some cases. Notably, the hierarchically porous TiP2O7 monoliths prepared from the α-TiP precursors have a good thermal robustness related to bulk density.

DOI： 10.1039/c8qi00146d

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Materials Chemistry A  

Iron(iii) oxyhydroxide and oxide monoliths with controlled multiscale porosity have been successfully fabricated via the sol-gel process accompanied by phase separation. The size of macropores was controlled by synthesis parameters such as starting compositions. The as-dried iron(iii) oxyhydroxide monoliths were amorphous and possessed surface areas over 340 m2 g-1, of which mesostructures could be further controlled by a heat-treatment at 250-350 °C without collapse of macrostructures and monolithic forms. When the as-dried gel was heated at 300 °C, the resultant gel transformed to crystalline α-Fe2O3 and exhibited a specific surface area of 124 m2 g-1. Heat-treatment at 350 °C resulted in the broadened size distribution of mesopores. The adsorption behavior of Congo red has revealed that the interconnected macroporous structure contributed to faster diffusion and better accessibility in a continuous flow-through set up, and the crack-free monolithic forms accounted for an advantageous use of the flow-through adsorbents.

DOI： 10.1039/c8ta01691g

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

A facile yet versatile approach to transparent, highly flexible, machinable, superinsulating organic-inorganic hybrid aerogels is presented. This method involves radical polymerization of a single alkenylalkoxysilane to obtain polyalkenylalkoxysilane, and subsequent hydrolytic polycondensation to afford a homogeneous, doubly cross-linked nanostructure consisting of polysiloxanes and hydrocarbon polymer units. Here we demonstrate that novel aerogels based on polyvinylpolysilsesquioxane (PVPSQ), polyallylpolysilsesquioxane (PAPSQ), polyvinylpolymethylsiloxane (PVPMS), and polyallylpolymethylsiloxane (PAPMS) are facilely prepared via this approach from vinyltrimethoxysilane (VTMS; or vinyltriethoxysilane, VTES), allyltrimethoxysilane (ATMS; or allyltriethoxysilane, ATES), vinylmethyldimethoxysilane (VMDMS), and allylmethyldimethoxysilane (AMDMS), respectively. These aerogels combine low density, uniform nanopores, high transparency, supercompressibility, high bendability, excellent machinability, and thermal superinsulation (λ = 14.5-16.4 mW m-1 K-1). More importantly, transparent, superflexible, superinsulating aerogels are obtained with PVPMS and PAPMS via highly scalable ambient pressure drying without any solvent-exchange and modifications for the first time. This work will open a new way to transparent, highly flexible porous materials, promising in the practical applications of thermal superinsulators, adsorbents, sensors, etc.

DOI： 10.1021/acs.chemmater.8b00563

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Nano  

Aerogels have many attractive properties but are usually costly and mechanically brittle, which always limit their practical applications. While many efforts have been made to reinforce the aerogels, most of the reinforcement efforts sacrifice the transparency or superinsulating properties. Here we report superflexible polyvinylpolymethylsiloxane, (CH2CH(Si(CH3)O2/2))n, aerogels that are facilely prepared from a single precursor vinylmethyldimethoxysilane or vinylmethyldiethoxysilane without organic cross-linkers. The method is based on consecutive processes involving radical polymerization and hydrolytic polycondensation, followed by ultralow-cost, highly scalable, ambient-pressure drying directly from alcohol as a drying medium without any modification or additional solvent exchange. The resulting aerogels and xerogels show a homogeneous, tunable, highly porous, doubly cross-linked nanostructure with the elastic polymethylsiloxane network cross-linked with flexible hydrocarbon chains. An outstanding combination of ultralow cost, high scalability, uniform pore size, high surface area, high transparency, high hydrophobicity, excellent machinability, superflexibility in compression, superflexibility in bending, and superinsulating properties has been achieved in a single aerogel or xerogel. This study represents a significant progress of porous materials and makes the practical applications of transparent flexible aerogel-based superinsulators realistic.

DOI： 10.1021/acsnano.7b07117

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PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Bunseki Kagaku  

A macroporous resorcinol-formaldehyde (RF) xerogel was synthesized via sol–gel reaction, accompanied by phase separation; a graphitized carbon monolith was then prepared by calcining the RF xerogel at a relatively low temperature (1200 °C) utilizing catalytic graphitization. The retention behaviors of metal-EDTA complexes on the carbon monolithic column were investigated. The carbon monolith exhibited catalytic activity for redox reactions, like porous graphitic carbon packing materials do; they oxidized Co(II)-EDTA to Co(III)-EDTA during elution. Their redox activity could be modified by treating with an eluent containing an oxidizing or reducing agent. A novel on-line redox derivatization HPLC system using a carbon monolithic column was developed for enhancing the separation selectivity. This on-line redox derivatization HPLC system consisted of two ODS columns as a separation column and one carbon monolithic column as redox derivatization unit placed between them. The Co(II)-EDTA migrated as its original oxidation state in the first ODS column, while it migrated as Co(III)-EDTA in the second ODS column, since Co(II)-EDTA was rapidly oxidized to Co(III)-EDTA in the carbon monolithic column. On the other hand, other metal-EDTA complexes migrated as their original oxidation states in these columns. Therefore, the Co-EDTA could be separated from the other metal-EDTA complexes. This on-line redox derivatization HPLC system was successfully used for determining the trace amount of cobalt in a reference copper alloy.

DOI： 10.2116/bunsekikagaku.67.469

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Catalysis Science and Technology  

Hierarchically porous niobium phosphate (NbP) was synthesised via a sol-gel method accompanied by phase separation and employed as a catalyst for fructose dehydration. The niobium precursor was prepared by digesting ammonium niobate(v) oxalate in aqueous H2O2 with citric acid as a chelating agent to prevent the precipitation of niobium hydroxide. Poly(acrylamide) and poly(ethylene glycol) were used as phase separation inducers to produce co-continuous macropores and gel skeletons. The NbP sample calcined at 600 °C for 8 h had a high surface area (SBET ∼140 m2 g-1) and large acidity (0.84 mmol-NH3 g-1). The NbP monolith was amorphous after calcination at 600 °C and transformed into an α-NbOPO4 phase at 1000 °C. The NbP monolith calcined at 600 °C was an efficient acid catalyst for the dehydration of fructose to 5-hydroxymethylfurfural in water (70% yield) or in aqueous dimethyl sulfoxide (90% yield). The productivity of HMF reached 7.3 × 10-2 mol h-1 per kg-solution at an initial fructose concentration of 10.0 wt% in water with a catalyst loading of 2.0 wt%.

DOI： 10.1039/c8cy00803e

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2147/JPR.S156326

PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Alloys and Compounds  

Hierarchically porous ZnAl2O4 spinel monolith derived from ionic precursors has been successfully prepared via the sol-gel route accompanied by phase separation in the presence of poly (ethylene oxide) (PEO) and propylene oxide (PO). Appropriate amounts of PEO as a phase-separation inducer and PO as a gelation mediator allow the formation of the xerogel with bicontinuous macrostructure and a monolithic shape. The macropore size of the resultant dried gel is mainly distributed in the range of 0.2–1 μm, and the whole porosity is about 65%. The dried gel is constructed by crystalline Zn–Al hydrotalcite, becoming amorphous after heat-treated at 300–500 °C in air, and is further transformed into single phase ZnAl2O4 spinel with plate-like shape at 600 °C. The macroporous structure is well maintained while the porosity increases to 75% and the surface area rises to 109 m2 g−1 after heat-treatment.

DOI： 10.1016/j.jallcom.2017.08.172

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Langmuir  

Reactions of chloromethyltrimethoxysilane (CMTMS) and its derived colloidal network polychloromethylsilsesquioxane (PCMSQ) have been investigated to extend the material design strategy toward functionalized and mechanically reinforced aerogels. In a carefully designed sol-gel system, CMTMS has afforded transparent aerogels in the presence of cationic surfactant. The surface chloromethyl groups with polarity and reactivity are shown to be useful for supporting nanostructures, with photoluminescent carbon dots (C-dots) prepared from polyethylenimine and citric acid as an example. Furthermore, since nucleophilic substitution (SN2) reactions on the surface chloromethyl groups are found to control the equilibrium of formation/dissociation of siloxane bonds, a new gelation strategy triggered by SN2 reactions in sol-gel has been developed. In the presence of nucleophilic organic species such as polyamines, a hybrid network consisting of PCMSQ cross-linked with a polyamine nucleophile can be prepared to enhance mechanical properties of aerogel.

DOI： 10.1021/acs.langmuir.7b03013

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PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Journal  

We report the shapeable synthesis of porous silica frameworks using polyacrylamide (PAAm) gel as an organic template and hydrolyzed silicon alkoxide as a silica source. Macroscopically shaped porous frameworks - such as plates, tablets and sheets - comprised of 20- to 40-nm diameter silica particles are obtained via PAAm-silica precursor gels. The mechanical properties (i.e., hardness and Young's modulus) of the silica frameworks depend on the packing density and are controlled by changing the silica content in PAAm gels.

DOI： 10.1038/pj.2017.62

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Omega  

Room-temperature stable macroporous mayenite electride (C12A7:e-) has been successfully prepared via a sol-gel method accompanied by phase separation, followed by heat-treatment and reduction processes. The obtained xerogel monoliths possess controllable macrostructure and a porosity of more than 60%, depending on adjusting the amount of poly(ethylene oxide) as a phase separation inducer. Heat-treatment allows the formation of multicrystals Ca12Al14O32Cl2 and Ca12Al14O33 (C12A7), and the porosity increases to 78.67% after being heat-treated at 1100 °C. Further reduction promotes the transformation from Ca12Al14O32Cl2 or C12A7 to C12A7:e- as well as the conversion from an insulator to a semiconductive electride. The carrier concentration of the electride reaches 3.029 × 1018 cm-3 after being reduced at 1100 °C under Ar atmosphere, and the porosity still remains 66%. The macrostructure of the resultant mayenite electride before and after heat-treatment and reduction is perfectly preserved, indicating that the obtained macroporous monolithic mayenite electride could be utilized in the electronic components.

DOI： 10.1021/acsomega.7b01121

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PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Astrophysical Journal Letters  

We report the study of the far-infrared (IR) sizes of submillimeter galaxies (SMGs) in relation to their dustobscured star formation rate (SFR) and active galactic nuclei (AGN) presence, determined using mid-IR photometry. We determined the millimeter-wave (λobs = 1100 μm) sizes of 69 Atacama Large Millimeter/ submillimeter Array (ALMA)-identified SMGs, selected with ≥10 δ confidence on ALMA images (F1100 μm = 1.7-7.4 mJy). We found that all of the SMGs are located above an avoidance region in the sizeflux plane, as expected by the Eddington limit for star formation. In order to understand what drives the different millimeter-wave sizes in SMGs, we investigated the relation between millimeter-wave size and AGN fraction for 25 of our SMGs at z=1-3. We found that the SMGs for which the mid-IR emission is dominated by star formation or AGN have extended millimeter-sizes, with respective median Rc,e = 1.6-0.21+0.34 and 1.5 -0.24+0.93 kpc. Instead, the SMGs for which the mid-IR emission corresponds to star-forming/AGN composites have more compact millimeter-wave sizes, with median Rc,e1.0 -0.20+0.20kpc. The relation between millimeter-wave size and AGN fraction suggests that this size may be related to the evolutionary stage of the SMG. The very compact sizes for composite star-forming/AGN systems could be explained by supermassive black holes growing rapidly during the SMG coalescing, star-formation phase.

DOI： 10.3847/2041-8213/aa9572

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CrystEngComm  

In this report, we demonstrate a facile and versatile methodology for synthesizing a series of titanium phosphates (TiPs) with various morphologies. The hydrothermal reactions of TiO2 in different concentrations of H3PO4 aq. yield 4 types of crystal structures with diverse shapes, such as nanoparticles, nanorods and nanosheets, which are assembled into a variety of flower-like morphologies. The dependence of the crystal phases and morphologies of TiPs on the synthesis conditions have been comprehensively investigated. This synthetic process can be further extended to other TiP derivatives incorporated with guest cations (e.g. NH4+ and Na+) simply by adding the corresponding phosphate salts to the starting composition, which leads to the morphological variation associated with the change of the crystal phase. The mechanism for the formation of the TiPs is discussed in terms of the stable Ti-based ion species relying on the pH value of the reaction solution. In addition, the correlation between the crystal structures and morphologies of TiPs and their electrochemical Li- and Na-ion storage behaviors are demonstrated as well, which discloses the different tendencies of morphological effects between the Li- and Na-ion systems.

DOI： 10.1039/c7ce01123g

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.chemmater.7b02431

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Asian Ceramic Societies  

Phase separation control is an important factor to prepare a porous monolith by an aqueous sol–gel reaction. Here, we report a surfactant-free synthesis method to obtain hydrophobic polymethylsilsesquioxane aerogels by copolymerizing a cationic-functionalized alkoxysilane N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride. The resultant materials have low-density, high visible-light transmittance, and high thermal insulating equivalent to those of prepared under the presence of surfactant.

DOI： 10.1016/j.jascer.2017.02.003

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Microporous and Mesoporous Materials  

A novel CO2 sorbent was prepared by modifying polyethyleneimine (PEI) on hierarchically porous silica (HPS) monoliths with well-defined macro-mesopores through wet impregnation method. HPS monoliths before and after functionalization were characterized by scanning electron microscopy (SEM), differential thermal analysis/thermogravimetry (DTA/TG), fourier transform infrared spectroscopy (FT-IR) and nitrogen adsorption/desorption analysis (BET), and the CO2 adsorption-regeneration properties of as-synthesized sorbents were investigated by thermogravimetric analysis (TG). The effects of loaded PEI amount as well as adsorption temperature and CO2 partial pressure on the CO2 adsorption performance of the as-prepared sorbents were also studied. The results showed that the porous structure of HPS-PEI sorbents was preserved after functionalization, while the specific surface area and pore volume decreased with increasing amount of amines to some extent. The use of PEI had a remarkable improvement on the CO2 adsorption capacity. With the increasing amount of PEI loaded, the CO2 adsorption capacity improved significantly. The highest CO2 adsorption capacity of 2.44 mmol (g sorbent)−1 was obtained at 75 °C in the CO2 partial pressure of 100 kPa for the HPS loaded with 60 wt% PEI. Adsorption/desorption cycles indicated that the PEI-modified HPS sorbents had a good stability and regeneration.

DOI： 10.1016/j.micromeso.2017.02.076

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Langmuir  

Transparent, low-density ethenylene-bridged polymethylsiloxane [Ethe-BPMS, O2/2(CH3)Si-CHCH-Si(CH3)O2/2] aerogels from 1,2-bis(methyldiethoxysilyl)ethene have successfully been synthesized via a sol-gel process. A two-step sol-gel process composed of hydrolysis under acidic conditions and polycondensation under basic conditions in a liquid surfactant produces a homogeneous pore structure based on cross-linked nanosized colloidal particles. Visible-light transmittance of the aerogels varies with the concentration of the base catalyst and reaches as high as 87% (at a wavelength of 550 nm for a 10 mm thick sample). Gelation and aging temperature strongly affect the deformation behavior of the resultant aerogels against uniaxial compression, and the obtained aerogels prepared at 80 °C show high elasticity after being unloaded. This highly resilient behavior is primarily derived from the rigidity of ethenylene groups, which is confirmed by a comparison with other aerogels with similar molecular structures, ethylene-bridged polymethylsiloxane and polymethylsilsesquioxane. Applicability of the addition reaction using a Diels-Alder reaction of benzocyclobutene has also been investigated, revealing that a successful addition takes place on the ethenylene linkings, which is verified using Raman and solid-state NMR spectroscopies. Insights into the effect of molecular structure on mechanical properties and the availability of surface functionalization provided in this study are important for realizing transparent aerogels with the desired functionality.

DOI： 10.1021/acs.langmuir.7b00434

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PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry - A European Journal  

Aerogels are attracting increasing attention due to their high thermal insulation ability as well as unique properties such as high porosity, surface area, and transparency. However, low mechanical strengths, originating from their unique porous structure, impede handling, formability, mass production, and extended applications. This minireview focuses on the strengthening of aerogels by several organic–inorganic hybridization strategies. In particular, successful strengthening methodologies, which employ organo-substituted alkoxysilanes as the single precursor for the sol–gel preparations, developed by the authors are highlighted. Moreover, improvements in compressive strength and elasticity lead to monolithic aerogel-like xerogels through ambient pressure drying. Correlations between structures in different length scales (e.g., molecular, network, and pore structure levels) and resultant mechanical properties are discussed for further understandings and better design toward mechanically improved aerogels/xerogels and their applications.

DOI： 10.1002/chem.201603680

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PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Abstract: Systematic investigations on the effect of synthetic conditions onto the properties of polyvinylsilsesquioxane (CH2=CHSiO3/2) aerogels have been conducted. As previously reported, transparent polyvinylsilsesquioxane aerogels can be obtained by utilizing a liquid surfactant as a solvent and a two-step sol–gel reaction involving hydrolysis catalyzed by a strong acid and subsequent polycondensation by a strong base. In this study, effects of base catalyst, gelation and aging conditions, amount of surfactant and concentration of acid catalyst have been investigated. With the optimized synthetic condition, the value of light transmittance reaches as high as 70% (at the wavelength of 550 nm for a 10-mm thick sample). Applicability of addition reactions utilizing thiol-ene reactions and hydrosilylation has also been surveyed. Thiol-ene reactions are relatively effective and can modify surface hydrophobicity and mechanical properties of polyvinylsilsesquioxane aerogels. In the case of hydrosilylation, a partial addition of a hydrosilane compound onto the polyvinylsilsesquioxane gel surface can be observed. Addition reactions, in particular thiol-ene reactions, are found to be profitable for implementing chemical functionality on the transparent aerogels. Graphical Abstract: [InlineMediaObject not available: see fulltext.]

DOI： 10.1007/s10971-017-4339-6

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

Flexible low-density materials, such as aerogels and polymer foams, have received increasing attention as energy absorbers and cushions that protect artificial products and human bodies. Microscopic geometry is a crucial factor determining their mechanical functions, i.e. strength and toughness (flexibility). However, it is a formidable challenge to combine these two properties because they are mutually elusive in general; stiff materials are brittle, while flexible ones are soft. Here, we demonstrate lightweight porous polymeric materials based on a common phenolic resin, resorcinol-formaldehyde (RF) gels, with salient combinatorial properties of high stiffness (up to 100 MPa) and good recoverable compressibility (against 80-90% strain), which can deliver remarkable energy absorption and dissipation performances repetitively. The detailed investigation reveals that the unique mechanical features originate from the synergetic effect of interdigitated hard and soft components in polymer matrices as well as exquisitely designed highly branched microstructures both generated through the spontaneous supramolecular self-assembly of the nonionic block copolymer (F127) and RF oligomer, which is essentially analogous to how natural organisms create biological structural materials, e.g. nacre and bone.

DOI： 10.1021/acs.chemmater.6b04706

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Applied Materials and Interfaces  

Multifunctional catalysts are of great interest in catalysis because their multiple types of catalytic or functional groups can cooperatively promote catalytic transformations better than their constituents do individually. Herein we report a new synthetic route involving the surface functionalization of nanoporous silica with a rationally designed and synthesized dihydrosilane (3-aminopropylmethylsilane) that leads to the introduction of catalytically active grafted organoamine as well as single metal atoms and ultrasmall Pd or Ag-doped Pd nanoparticles via on-site reduction of metal ions. The resulting nanomaterials serve as highly effective bifunctional dehydrogenative catalysts for generation of H2 from formic acid.

DOI： 10.1021/acsami.6b12972

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Applied Materials and Interfaces  

Polymethylhydrosiloxane has been grafted on the surface of a hierarchically porous silica monolith using a facile catalytic reaction between Si-H and silanol to anchor the polymer. This easy methodology leads to the functionalization of the surface of a silica monolith, where a large amount of free Si-H bonds remain available for reducing metal ions in solution. Palladium nanoparticles of 15 nm have been synthesized homogeneously inside the mesopores of the monolith without any stabilizers, using a flow of a solution containing Pd2+. This monolith was used as column-type fixed bed catalyst for continuous flow hydrogenation of styrene and selective hydrogenation of 3-hexyn-1-ol, in each case without a significant decrease of the catalytic activity after several hours or days. Conversion, selectivity, and stereoselectivity of the alkyne hydrogenation can be tuned by flow rates of hydrogen and the substrate solution, leading to high productivity (1.57 mol g(Pd)-1 h-1) of the corresponding cis-alkene.

DOI： 10.1021/acsami.6b12653

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Abstract: Low-density, transparent aerogels based on a hexylene-bridged polysilsesquioxane ([O1.5Si–(CH2)6–SiO1.5]n) network have been prepared for the first time via a simple sol–gel process. An optimized base-catalyzed one-step hydrolysis–polycondensation process of a bridged alkoxysilane precursor 1,6-bis(trimethoxysilyl)hexane in a low-polarity solvent N,N-dimethylformamide allows for the formation of a pore structure of a length scale of several tens nanometers, resulting in low-density, transparent aerogels after supercritical drying. Because of the incorporated organic moiety that bridges the silicon atoms in the network, these aerogels show higher flexibility and strength against compression and bending as compared to silica aerogel counterparts. In addition, minimizing the residual silanol groups in the network by a surface modification with hexamethyldisilazane has further improved resilience after compression and bending flexibility and strength, due to the decreased chance of the irreversible formation of the siloxane bonds upon compression. The resulting trimethylsilylated hydrophobic gels have been subjected to ambient pressure drying to obtain xerogels, resulting in low-density (0.13 g cm−3, 90 % porosity), transparent (71 % transmittance) xerogels. These results are promising for the development of transparent thermal superinsulators applicable to window insulating systems that manage heat transfer in a more efficient way. Graphical Abstract: [Figure not available: see fulltext.]

DOI： 10.1007/s10971-016-4077-1

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：RSC Advances  

Nanostructured amorphous silica in rice plants (biosilica or plant opal) plays an important role in plant growth related to food production. However, the same silica has a structural supporting role as well that has not been uncovered. The current study focuses on the structural design of the two main types of biosilicas in rice plants for the improvement of their mechanical properties. One structural motif is plate-like silicas, which cover most of the surfaces of leaf blades. Another is fan-shaped silicas, which are aligned inside leaf blades, providing a stiff backbone. These biosilica structures consist of 10-100 nm diameter nanoparticles. The mechanical properties, such as hardness and Young's modulus, of the biosilicas are associated with their relative density. Thus, the rice plant mechanics is inferred to be designed by changing the packing of the nanoparticles. Silica plates consisting of loosely packed particles have relatively low density and high flexibility enabling coverage of leaf blade surfaces, while fan-shaped silicas, which consist of tightly packed nanoparticles, are rigid to support the leaf blades as a backbone.

DOI： 10.1039/c6ra27317c

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymers and Polymer Composites  

Increasing the efficiency of encapsulation of ingredients into spherical capsules can decrease the manufacturing costs of the capsules. Ingredients can be encapsulated with high efficiency (>99%) into nondegradable hard resin capsules prepared by polymerization of spherical droplets of trimethylolpropane trimethacrylate (TRIM) monomer placed on a superoleophobic material. Poly(methyl methacrylate) (PMMA) resin is a more versatile capsule material than poly-TRIM resin. In this study, the efficiency of encapsulation in PMMA resin capsules prepared from methyl methacrylate (MMA) monomer was investigated. To reduce the volatility of the MMA monomer, pre-polymerized MMA was used for capsule preparation. Although non-volatile α-tocopherol and doxorubicin could be encapsulated in the capsules with high efficiency by heat polymerization at 60°C for 3 h, the efficiency for volatile tetradecane was much lower (approximately 60%) because it evaporated. Furthermore, even when using pre-polymerized MMA, more than 70% of the prepolymer evaporated during polymerization. To prevent the evaporation of tetradecane and the prepolymer, ultraviolet photopolymerization was adopted because it was faster and could be conducted at a lower temperature. The photopolymerization prevented the evaporation of the prepolymer and increased the efficiency of encapsulation of tetradecane (approximately 90% efficiency). This polymerization system is effective for encapsulation of ingredients in PMMA capsules with high efficiency.

DOI： 10.1177/096739111702500202

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Langmuir  

Transparent, monolithic aerogels with nanosized colloidal skeletons have been obtained from a single precursor of 1,2-bis(methyldiethoxysilyl)ethane (BMDEE) by adopting a liquid surfactant and a two-step process involving strong-acid, followed by strong-base, sol-gel reactions. This precursor BMDEE forms the ethylene-bridged polymethylsiloxane (EBPMS, O2/2(CH3)Si-CH2CH2-Si(CH3)O2/2) network, in which each silicon has one methyl, two bridging oxygens, and one bridging ethylene, exhibiting an analogous structure to that of the previously reported polymethylsilsesquioxane (PMSQ, CH3SiO3/2) aerogels having one methyl and three bridging oxygen atoms. Obtained aerogels consist of fine colloidal skeletons and show high visible-light transparency and a flexible deformation behavior against compression without collapse. Similar to the PMSQ aerogels, a careful tuning of synthetic conditions can produce low-density (0.19 g cm-3) and highly transparent (76% at 550 nm, corresponding to 10 mm thick samples) xerogels via ambient pressure drying by solvent evaporation due to their high strength and resilience against compression. Moreover, EBPMS aerogels exhibit higher bending strength and bending strain at break against the three-point bending mode compared to PMSQ aerogels. This improved bendability is presumably derived from the introduced ethylene-bridging parts, suggesting the potential for realizing transparent and bendable aerogels in such polysiloxane materials with organic linking units.

DOI： 10.1021/acs.langmuir.6b03249

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Catalysis Communications  

We report the application of hierarchically porous zirconium phosphate monoliths with high surface area as acidic heterogeneous catalysts for the dehydration of xylose into furfural. Analyses by NH3-temperature programmed desorption and 31P solid state NMR reveal the presence of both Lewis and Brønsted acid sites in the as-synthesized zirconium phosphate monolith and that calcined at 600 °C. High accessibility and availability of the acidic sites and easy separation of the monolith from the liquid medium result in good catalytic activity (initial reaction rate for furfural production as 8.7 mmol gcat− 1 h− 1) with easy handling of the catalyst.

DOI： 10.1016/j.catcom.2016.09.014

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

Silica aerogels are unique porous materials possessing high visible-light transparency and low thermal conductivity. However, the practical applications are limited due to the native fragility of silica, and a lot of research focuses on the improvement of mechanical properties by organic-inorganic hybridization, and so forth. Here, the first synthesis of polyethylsilsesquioxane (PESQ; CH3CH2SiO1.5) and polyvinylsilsesquioxane (PVSQ; CH2 - CHSiO1.5) aerogels is reported. The resultant PESQ and PVSQ aerogels obtained through a two-step acid-base sol-gel reaction in a surfactant-based solution exhibit visible-light transmittance and flexibility against compression without collapsing. The microstructural variations of these aerogels are systematically investigated by positron annihilation lifetime spectroscopy (PALS) in order to clarify the differences in properties derived from substituent groups. Furthermore, a post cure on the PVSQ wet gel using a radical initiator induces polymerization of vinyl groups in the solid network, resulting in mechanically reinforced aerogels with higher compressive modulus and resilience. This chemical modification, similar to vulcanization in silicone rubber materials, helps to produce xerogels with comparable properties to those of aerogels via ambient pressure drying. Since the resultant xerogel obtained from the vulcanization of PVSQ shows sufficiently low thermal conductivity of 15.3 mW m-1 K-1, these novel polysilsesquioxane materials are promising for transparent aerogels/xerogels superinsulators.

DOI： 10.1021/acs.chemmater.6b01936

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10971-016-4124-y

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Porous Materials  

Yttria-stabilized zirconia monoliths with well-defined macropores and high porosity have been successfully fabricated via sol–gel process accompanied by phase separation. Propylene oxide acts as an acid consumer to mediate sol–gel process, and poly (ethylene oxide) is used to induce phase separation. Ethylene glycol is applied as chelating agent, and formamide serves as drying control chemical additive to inhibit cracking during drying stage. Proper proportion of the starting compositions allows the generation of well-defined macroporous YSZ monoliths with co-continuous skeletons and porosity as high as more than 60 %. The dried gels are amorphous and crystalline of ZrO2 precipitates after heat treatment between 400 and 1200 °C without formation of monoclinic ZrO2, which indicating a wide application prospects.

DOI： 10.1007/s10934-016-0143-x

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

This report demonstrates a facile one-pot synthesis of hierarchically porous resorcinol-formaldehyde (RF) gels comprising mesoporous nanorod assemblies with two-dimensional (2D) hexagonal ordering by combining a supramolecular self-assembly strategy in the nanometer scale and phase separation in the micrometer scale. The tailored multilevel pore system in the polymer scaffolds can be preserved through carbonization and thermal activation, yielding the multimodal porous carbon and activated carbon (AC) monoliths. The thin columnar macroframeworks are beneficial for electrode materials due to the short mass diffusion length through small pores (micro- and mesopores). By employing the nanostructured AC monolith as a binder-free electrode for supercapacitors, we have also explored the capability of "water-in-salt" electrolytes, aiming at high-voltage aqueous supercapacitors. Despite that the carbon electrode surface is supposed to be covered with salt-derived decomposition products that hinder the water reduction, the effective surface area contributing to electric double-layer capacitance in 5 M bis(trifluoromethane sulfonyl)imide (LiTFSI) is found to be comparable to that in a conventional neutral aqueous electrolyte. The expanded stability potential window of the superconcentrated electrolyte allows for a 2.4 V-class aqueous AC/AC symmetric supercapacitor with good cycle performance.

DOI： 10.1021/acs.chemmater.6b01261

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その他リンク： http://orcid.org/0000-0002-8069-4780

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

DOI： 10.1021/acs.chemmater.6b01010

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Microporous and Mesoporous Materials  

A versatile synthetic method has been developed for the fabrication of metal zirconium phosphate (MZP) macroporous monoliths via a sol-gel process accompanied by phase separation. More than 30 kinds of MZP monolithic polycrystalline monoliths with co-continuous macroporous structure have been synthesized by simply adding the target metal salt in the starting solution with optimized compositions. Glycerol, due to its high boiling point, plays the key role as the solvent to prevent metal salt from recrystallization, allowing a homogeneous distribution of metal salts over the polymerizing zirconium phosphate network. Hierarchically porous polycrystalline strontium zirconium phosphate (SrZrP) monolith has been obtained when the dried gel was calcined at 1000 °C. Very low thermal expansion (coefficient of thermal expansion (CTE) as 1.4 × 10-6 K-1) over a wide temperature range (38 °C-1000 °C) together with good mechanical properties (flexural modulus as 8.0 GPa from 3 point bending test and Young's modulus as 1.9 GPa from uniaxial compression test) has been demonstrated, while high porosity (43%) due to the presence of macropores reduces bulk density. As compared with dense ceramics of the same composition, the CTE value is lower and can be attributed to the presence of nanometer-sized small pores, which absorbs the anisotropic thermal expansion of each crystallite in the macropore skeletons at elevated temperatures.

DOI： 10.1016/j.micromeso.2015.12.002

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Non-Crystalline Solids  

Ambient pressure drying of polymethylsilsesquioxane gels via dynamic shrinkage-reexpansion has been investigated for preparation of aerogel-like xerogels and their application to thermal superinsulators. An extended aging of wet gels in aqueous solution containing precursor-derived species is found to be crucial in obtaining crack-free, monolithic xerogels with sufficiently low thermal conductivity (13.7 mW m- 1 K- 1) at bulk density of 0.140 g cm- 3 (porosity - 90%).

DOI： 10.1016/j.jnoncrysol.2015.12.016

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Bulletin  

Spherical capsules have been used in various fields because of their many advantages. In many industrial applications, hydrophobic hard resins (e.g., polyacrylate, epoxy and polystyrene) are used as a shell material for stable packaging of ingredients within capsules. However, it is difficult to encapsulate ingredients in such capsules without loss by conventional techniques. The purpose of this study was to encapsulate hydrophobic ingredients within polyacrylate resin capsules with ultrahigh efficiency. In our methodology, a small volume of resin monomer solution containing the ingredients was first placed on a superoleophobic material and the resulting spherical droplets were then solidified by polymerization of the monomer. Doxorubicin (an anticancer drug), α-tocopherol (an antioxidant) and tetradecane (a phase change material used for heat storage) could be encapsulated in spherical hard capsules with almost no loss by heat and photopolymerization. We showed that tetradecane in the capsules had almost identical thermal properties to pure tetradecane. These results demonstrate that our technique is promising for encapsulation of hydrophobic ingredients in hard resin capsules.

DOI： 10.1007/s00289-015-1497-y

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.chroma.2015.12.019

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：New Journal of Chemistry  

Hierarchically porous titanium phosphate monoliths combining well-defined co-continuous macropores and accessible large mesopores have been synthesized for the first time via a sol-gel process accompanied by phase separation using titanium oxysulfate and phosphoric acid as precursors. The macropore size was tunable over a broad range from 0.6 μm to 10 μm by changing the starting composition, while the mesopore size and the specific surface area of the as-synthesized amorphous monoliths are 21 nm and 320 m2 g-1, respectively. Crystallization of the gel network can be induced in two different ways. Calcination at elevated temperature (800 °C) leads to the formation of TiP2O7 and the collapse of both the macro- and meso-structures, while the solvothermal treatment of the as-synthesized gel in ethylene glycol leads to the formation of platy crystals of titanium phosphate with a layered structure at relatively low temperature. The titanium phosphate monoliths with a hierarchically porous structure are expected to be useful in various applications such as continuous-flow catalysis, water remediation and ion batteries.

DOI： 10.1039/c5nj02820e

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ChemElectroChem  

Hard carbons have immense potential as anode materials for Na-ion batteries, because the expanded graphene interlayers and nanovoids between randomly stacked aromatic fragments can accommodate a substantial amount of sodium. However, the large irreversible capacity in the first cycle still remains as a significant issue in terms of a practicable battery technology. Here, we show that hard carbon electrodes derived from a common phenol resin deliver a high reversible capacity within the narrow potential range of 0.1-0.005V (vs. Na+/Na) and an excellent initial coulombic efficiency up to 95%. The former allows the sustainable high voltage, whereas the latter minimizes the amount of unavailable Na+ in a closed cell. The findings in this work put forward a guideline for manufacturing hard carbon electrodes, which goes against the current trend of nanostructuring and downsizing. It's got potential: Carbon electrodes derived from a phenol resin for Na-ion batteries show potential profiles just like those of Li-ion intercalation/extraction into/from graphite. The high reversible capacity and the excellent initial coulombic efficiency well above 90% have great potential for a practical use.

DOI： 10.1002/celc.201500412

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Sol-gel synthesis of macroporous polymethylsilsesquioxane (PMSQ) monoliths has been successful over the past decade, and applications to separation media have been investigated. However, the control of mesopores to tailor hierarchical porosity, which is promising for improvement of the separation efficiency, remains challenging. In particular, an independent control of meso- and macropores has not been achieved in PMSQ. Herein we present a method to synthesize PMSQ monoliths with well-defined macropores and controlled mesostructure (pore size ranging from 10 to 60 nm, total pore volume from 0.2 to 0.6 cm(3) g(-1)) via sol-gel accompanied by phase separation. Different Pluronic-type nonionic surfactants were used to control phase separation of the hydrophobic PMSQ network in aqueous media. Due to different packing density of the colloidal PMSQ constituents in the continuous skeletons in the micrometer-scale (termed as macropore skeletons) and their rearrangements through the hydrothermal post-treatment under basic conditions, mesopore characteristics have been successfully controlled independently of the preformed macropore structure. Separation columns for high-performance liquid chromatography (HPLC) have been fabricated using the PMSQ monoliths, and acceptable separation performances in both the reversed-phase and normal-phase modes have been demonstrated due to the presence of both hydrophilic silanol groups and hydrophobic methyl groups. (C) 2015 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.123.770

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the Ceramic Society of Japan  

Conventionally, commercialized spherical silicone powders, such as silicone resin powder [INCI: POLYMETHYLSILSESQUIOXANE (PMSQ beads)]1) and silicone rubber powder [INCI: DIMETHICONE/VINYL DIMETHICONE CROSSPOLYMER (DVDC beads)],2) have been formulated into cosmetics for soft and smooth feeling. Due to the low crosslink density, silicone rubber powder shows soft touch and high oil absorption. However, it is too agglomerative to be formulated into powder foundation. In this work, we have developed the novel soft touch spherical silicone beads made from methyltrimethoxysilane (MTMS) and dimethyldimethoxysilane (DMDMS), using a surfactant, cetyltrimethylammonium chloride (CTAC). The preparation procedure of the novel silicone beads requires only homogeneous mixing and includes no other complicated operations. The 29Si NMR and TG measurements indicate that DMDMS is randomly incorporated into the methylsiloxane network. The particle size of the beads can be controlled by the concentration of urea as well as by the stirring speed in the solgel reaction. By carefully adjusting these parameters, the size of the beads has been optimized for the use in make-up cosmetics. It was revealed by various evaluation measurements that the novel silicone beads exhibit unique characteristics, such as softness, low oil absorption, high transparency and light diffusion effects.

DOI： 10.2109/jcersj2.123.714

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Separation Science  

The optimization of a porous structure to ensure good separation performances is always a significant issue in high-performance liquid chromatography column design. Recently we reported the homogeneous embedment of Ag nanoparticles in periodic mesoporous silica monolith and the application of such Ag nanoparticles embedded silica monolith for the high-performance liquid chromatography separation of polyaromatic hydrocarbons. However, the separation performance remains to be improved and the retention mechanism as compared with the Ag ion high-performance liquid chromatography technique still needs to be clarified. In this research, Ag nanoparticles were introduced into a macro/mesoporous silica monolith with optimized pore parameters for high-performance liquid chromatography separations. Baseline separation of benzene, naphthalene, anthracene, and pyrene was achieved with the theoretical plate number for analyte naphthalene as 36 000 m-1. Its separation function was further extended to cis/trans isomers of aromatic compounds where cis/trans stilbenes were chosen as a benchmark. Good separation of cis/trans-stilbene with separation factor as 7 and theoretical plate number as 76 000 m-1 for cis-stilbene was obtained. The trans isomer, however, is retained more strongly, which contradicts the long- established retention rule of Ag ion chromatography. Such behavior of Ag nanoparticles embedded in a silica column can be attributed to the differences in the molecular geometric configuration of cis/trans stilbenes.

DOI： 10.1002/jssc.201500444

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

The present report demonstrates a new technique for doping heteroatoms (nitrogen, phosphorus, and sulfur) into carbon materials via a versatile post-treatment. The heat-treatment of carbon materials with a reagent, which is stable at ambient temperatures and evolves reactive gases on heating, in a vacuum-closed tube allows the introduction of various heteroatom-containing functional groups into a carbon matrix. In addition, the sequential doping reactions give rise to dual- and triple-heteroatom-doped carbons. The pore properties of the precursor carbon materials are preserved through each heteroatom doping process, which indicates that independent tuning of heteroatom doping and nanostructural morphology can be achieved in various carbon materials. The electrochemical investigation on the undoped and doped carbon monolithic electrodes applied to supercapacitors provides insights into the effects of heteroatom doping on electrochemical capacitance. (Figure Presented).

DOI： 10.1021/acs.chemmater.5b01349

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.inorgchem.5b00810

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1088/1468-6996/16/2/025003

PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Inorganic Chemistry  

A preceramic polymer route from Ti-based inorganic-organic hybrid networks provides electroconductive N-doped reduced titanium oxides (Ti n O 2n-1 ) and titanium oxynitrides (TiO x N y ) with a monolithic shape as well as well-defined porous structures. This methodology demonstrates an advantageously lower temperature of the crystal phase transition compared to the reduction of TiO 2 by carbon or hydrogen. In this study, the effect of calcination conditions on various features of the products has been explored by adopting three different atmospheric conditions and varying the calcination temperature. The detailed crystallographic and elemental analyses disclose the distinguished difference in the phase transition behavior with respect to the calcination atmosphere. The correlation between the crystallization and nitridation behaviors, porous properties, and electric conductivities in the final products is discussed.

DOI： 10.1021/ic502972v

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography A  

Prototype small-size (1.0mm I.D., 5cm long) columns for reversed-phase HPLC were evaluated in relation to instrument requirements. The performance of three types of columns, monolithic silica and particulate silica (2μm, totally porous and 2.6μm, core-shell particles) was studied in the presence of considerable or minimal extra-column effects, while the detector contribution to band broadening was minimized by employing a small size UV-detector cell (6- or 90nL). A micro-LC instrument having small system volume (<1μL) provided extra-column band variance of only 0.01-0.02μL2. The three columns generated about 8500 theoretical plates for solutes with retention factor, k>1-3 (depending on the column), in acetonitrile/water mobile phase (65/35=vol/vol) at 0.05mL/min, with the instrument specified above. The column efficiency was lower by up to 30% than that observed with a 2.1mm I.D. commercial column. The small-size columns also provided 8000-8500 theoretical plates for well retained solutes with a commercial ultrahigh-pressure liquid chromatography (UHPLC) instrument when extra-column contributions were minimized. While a significant extra-column effect was observed for early eluting solutes (k<2-4, depending on column) with methanol/water (20/80=vol/vol) as weak-wash solvent, the use of methanol/water=50/50 as wash solvent affected the column efficiency for most analytes. The results suggest that the band compression effect by the weak-wash solvent associated with partial-loop injection may provide a practical means to reducing the extra-column effect for small-size columns, while the use of an instrument with minimum extra-column effect is highly desirable.

DOI： 10.1016/j.chroma.2015.01.014

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その他リンク： http://orcid.org/0000-0002-8069-4780

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Advanced Energy Materials  

Integrated design of both porous structure and crystalline morphology is expected to open up the way to a new class of materials. This report demonstrates new nanostructured Li4Ti5O12 materials with hierarchically porous structures and flower-like morphologies. Electrochemical studies of the electrodes of Li-ion and Na-ion batteries clearly reveal the advantage of nanoarchitectural design of active materials. In addition, the temperature dependence of Na+-insertion/extraction capacity in relation to Li4Ti5O12 electrodes is for the first time evaluated and it is found that elevation of the cell operating temperature effectively improves the rate capability of the Na-ion batteries. Based on the new findings, it is suggested that specially designed Li4Ti5O12 materials allow for high-performance Na-ion batteries that are available as large-scale storage devices for applications such as automotive and stationary energy storage.

DOI： 10.1002/aenm.201400730

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：New Journal of Chemistry  

Copper hydroxide-based monolithic xerogels with controlled hierarchical pores have been prepared directly by a sol-gel process from an ionic precursor, CuCl2·2H2O. Propylene oxide acts as a gelation inducer by increasing pH homogeneously in a reaction solution. Poly(acrylamide) is utilized not only to control macroscopic phase separation but also to support the network physically. Glycerol contributes to the formation of monolithic gels by suppressing the growth of copper hydroxide crystals. An appropriate starting composition leads to co-continuous gel skeletons and macropores. Although the as-dried gels were amorphous, post-treatments (calcination and solvothermal treatment) formed metallic copper and copper oxides (CuO and Cu2O) without the collapse of the monolithic form and macrostructure.

DOI： 10.1039/c5nj00479a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Communications  

The synthesis of highly crystalline macro-meso-microporous monolithic Cu3(btc)2 (HKUST-1; btc3- = benzene-1,3,5-tricarboxylate) is demonstrated by direct conversion of Cu(OH)2-based monoliths while preserving the characteristic macroporous structure. The high mechanical strength of the monoliths is promising for possible applications to continuous flow reactors. This journal is

DOI： 10.1039/c4cc09694k

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c5nj00490j

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Science  

The coordination replication technique is employed for the direct conversion of a macro- and mesoporous Cu(OH)<inf>2</inf>-polyacrylamide composite to three-dimensional superstructures consisting of the flexible porous coordination polymers, Cu<inf>2</inf>(bdc)<inf>2</inf>(MeOH)<inf>2</inf> and Cu<inf>2</inf>(bdc)<inf>2</inf>(bpy) (bdc^2- = 1,4-benzenedicarboxylate, bpy = 4,4′-bipyridine). Detailed characterization of the replicated systems reveals that the structuralization plays an important role in determining the adsorptive properties of the replicated systems, and that the immobilization of the crystals within a higher-order architecture also affects its structural and dynamic properties. The polyacrylamide polymer is also found to be crucial for maintaining the structuralization of the monolithic systems, and in providing the mechanical robustness required for manual handling. In all, the results discussed here demonstrate a significant expansion in the scope of the coordination replication strategy, and further confirms its utility as a highly versatile platform for the preparation of functional three-dimensional superstructures of porous coordination polymers.

DOI： 10.1039/c5sc02034d

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c5ra03491d

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c5dt01672j

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the Electrochemical Society  

We report the fabrication of porous titanium nitride (TiN) monoliths through the ammonolysis of porous TiO2 monoliths prepared via the sol-gel process accompanied by phase separation. The obtained TiN monoliths possess good mechanical strength as well as excellent electric conductivity with a superconducting transition at Tc ~ 5.0 K. We have investigated the electrochemical properties of the porous TiN monoliths as an electrode using various electrolytes. The results reveal that the pseudocapacitance of TiN increases in the order of K+ < Na+ < Li+ contrary to the case of EDL capacitance in neutral aqueous electrolytes. It is also found that acidic and strongly basic electrolytes are not suitable due to high corrosivity, while there is no significant deterioration when neutral aqueous electrolytes and organic electrolytes are used.

DOI： 10.1149/2.0491501jes

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：RSC Advances  

Removal of toxic substances from industrial wastes is an urgent issue for realizing a sustainable society. Layered double hydroxides (LDHs) are expected to be an effective adsorbent for toxic anions, especially oxyanions, because of their high anion adsorption capacity and reusability. Monolithic LDH materials with rational meso- and macropores are expected to show high adsorption capacity/rate towards targeted toxic substances owing to their large specific surface area and liquid transport property. Besides fabricating hierarchical pores, size control of microcages in LDH crystals is required to achieve selective removal of oxyanions. Herein, we prepared hierarchically porous monolithic LDH composites with tunable microcages by changing the combination of cationic species in the LDH crystal. Monolithic Mg-, Mn-, Fe-, Co- and Ni-Al type LDH composites with hierarchical pores were successfully prepared via an epoxide-mediated sol-gel reaction accompanied with phase separation. The monolithic Co-Al type LDH composite with hierarchical pores exhibited the highest CrO<inf>4</inf>^2- adsorption capacity because its microcage size easily fits the CrO<inf>4</inf>^2- size. Also Co-Al type LDH composites adsorbed different oxyanions, depending on their affinity with the LDH, in a SO<inf>4</inf>^2-, CrO<inf>4</inf>^2-, MoO<inf>4</inf>^2- and HVO<inf>4</inf>^2- co-existing solution. The pore size controllability in discrete length-scales of micrometers, nanometers, and picometers offers LDHs with tailored surface chemistries and physical properties desirable for effective and selective oxyanion adsorption.

DOI： 10.1039/c5ra05942a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：New Journal of Chemistry  

Monolithic mayenite with well-defined macropores has been successfully synthesized from ionic precursors via a sol-gel process accompanied by phase separation. The addition of propylene oxide (PO) to the starting solution leads to homogenous gelation and modifies the gel skeleton, whereas the addition of poly(ethylene oxide) (PEO) induces phase separation. Glycol acts as a chelating agent to suppress the precipitation of Ca2+ ions, and formamide works as a drying control chemical additive to enhance the drying behavior. Appropriate amounts of solvents, PEO, and PO allow the formation of calcium aluminate gels with co-continuous macroporous structure. The reaction mechanism of the sol-gel process of the Ca-Al-O system is also investigated by TG-DSC, FT-IR and NMR. The dried gels are amorphous and the crystalline phase Ca12Al14O32Cl2 forms after heat-treatment at 1000 °C in air, while the macroporous structure is preserved. The resultant monoliths before and after heat-treatment possess both high porosity and smooth and dense skeletons. This journal is

DOI： 10.1039/c4nj00898g

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その他リンク： http://orcid.org/0000-0002-8069-4780

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Dalton Transactions  

A facile and "green" method was proposed to introduce Ag nanoparticles (Ag NPs) into the hierarchically monolithic silica uniformly in the presence of (3-aminopropyl)-triethoxysilane (APTES) and ethylene glycol. APTES is used to modify the monolith by incorporating amino groups onto the surface of meso-macroporous skeletons, while ethylene glycol is employed as the productive reductant. Ag NPs are homogeneously immobilized in hierarchically monolithic silica after reduction and drying at 40 °C for different duration times, and the embedded amount of Ag NPs can reach 15.44 wt% when treated once. The embedment of Ag NPs increases with the repeat treatment and the APTES amount, without uncontrollable crystalline growth. The surface areas of Ag NPs embedded in silica monoliths after heat treatment at 300 and 400 °C are higher than those before heat treatment. The modification via APTES and the embedment of Ag NPs does not spoil the morphology of monolithic silica, while changing the pore structures of the monolith. A tentative formation process and a reduction mechanism are proposed for the modification, reduction and embedment. Ag NPs embedded in monolithic silica is promising for wide applications such as catalysis and separation. This journal is © the Partner Organisations 2014.

DOI： 10.1039/C4DT00655K

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ja504115d

PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography A  

Effective medium theory (EMT) expressions for the B-term band broadening in monolithic silica columns are presented at the whole-column as well as at the mesoporous skeleton level. Given the bi-continuous nature of the monolithic medium, regular as well as inverse formulations of the EMT-expressions have been established. The established expressions were validated by applying them to a set of experimental effective diffusion (Deff)-data obtained via peak parking on a number of 1st and 2nd generation monolithic silica columns, as well as to a set of numerical diffusion simulations in a simplified monolithic column representation (tetrahedral skeleton model) with different external porosities and internal diffusion coefficients. The numerically simulated diffusion data can be very closely represented over a very broad range of zone retention factors (up to k″=80) using the established EMT-expressions, especially when using the inverse variant. The expressions also allow representing the experimentally measured effective diffusion data very closely. The measured Deff/Dmol-values were found to decrease significantly with increasing retention factor, in general going from about Deff/Dmol=0.55 to 0.65 at low k″ (k″≅1.5-3.8) to Deff/Dmol=0.25 at very high k″ (k″≅40-80). These values are significantly larger than observed in fully-porous and core-shell particles. The intra-skeleton diffusion coefficient (Dpz) was typically found to be of the order of Dpz/Dmol=0.4, compared to Dpz/Dmol=0.2-0.35 observed in most particle-based columns. These higher Dpz/Dmol values are the cause of the higher Deff/Dmol values observed. In addition, it also appears that the higher internal diffusion is linked to the higher porosity of the mesoporous skeleton that has a relatively open structure with relatively wide pores. The observed (weak) relation between Dpz/Dmol and the zone retention factor appears to be in good agreement with that predicted when applying the regular variant of the EMT-expression directly to the mesoporous skeleton level. © 2014 Elsevier B.V.

DOI： 10.1016/j.chroma.2014.04.099

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その他リンク： http://orcid.org/0000-0002-8069-4780

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/am501822y

PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jeurceramsoc.2013.08.016

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the European Ceramic Society  

In this study, hierarchically porous bicrystalline nitrogen-doped titania (N-doped TiO2) monolithic material was fabricated by a simple two-step approach: (i) preparation of TiO2 porous monolith by a sol-gel process of titanium alkoxide in a mild condition utilizing a chelating agent and mineral salt and (ii) annealing of TiO2 porous monolith obtained under a modest flow of ammonia gas at 700°C for 2h. The phase composition, crystal structure, morphology, pore structure, and porous properties of the final product were studied by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), mercury porosimetry, and nitrogen physisorption measurement, respectively. The resultant N-doped TiO2 porous monolith possesses a bicrystalline (anatase and rutile) framework with a well-defined macroporosity. The results from X-ray photoelectron spectroscopy (XPS) confirm the formation of OTiN bonds in the N-doped TiO2 porous monolith. The photocatalytic activity of N-doped TiO2 porous monolith was evaluated by the photodegradation of Rhodamine B over the samples under visible light. Nearly 50% of Rhodamine B in aqueous solution was efficiently degraded by N-doped TiO2 porous monolith with the mixed-phase of anatase and rutile under visible light within 120min. © 2013 Elsevier Ltd.

DOI： 10.1016/j.jeurceramsoc.2013.10.009

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J-GLOBAL

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecular Rapid Communications  

The direct synthesis of structurally well-defined protic polymeric ionic liquid (PIL) with controlled molecular weight and molecular weight distribution is examined using N,N-diethyl-N-(2-methacryloylethyl) ammonium bis(tri-fluoromethylsulfonyl)imide (DEMH-TFSI) as a monomer. Three polymerization methods, namely, atom transfer radical polymerization (ATRP), activators regenerated by electron transfer (ARGET)-ATRP, and organotellurium-mediated living radical polymerization (TERP) are employed in this study. While the polymerization by ATRP is slow and does not reach high monomer conversion that under ARGET-ATRP and TERP proceeds smoothly and affords structurally well-defined poly(DEMH-TFSI)s. TERP is especially efficient for the control and poly(DEMH-TFSI)s with low to high molecular weights (M̄n = 49 100-392 500) and narrow molecular weight distributions (M̄w/M̄n = 1.17-1.46) are obtained. These results represent the first example of synthesis of a structurally well-defined protic, ammonium PIL by direct polymerization of the protic ionic liquid monomer. The polymerization of N,N-diethyl-N-(2- methacryloylethyl)-N-methylammonium bis(trifluoromethylsulfonyl)imide (DEMM-TFSI), which possesses a quaternary ammonium salt, also proceeds in a highly controlled manner under TERP conditions. A diblock copolymer, polystyrene-block-poly(DEMH-TFSI), is also successfully synthesized by TERP. Structurally well-defined protic polymeric ionic liquid is prepared by the direct polymerization of protic ammonium-salt ionic liquid monomers, N,N-diethyl-N-(2-methacryloylethyl) ammonium bis(tri-fluoromethylsulfonyl)imide (DEMH-TFSI), under ARGET-ATRP and TERP conditions. TERP is especially suitable for the controlled polymerization and afforded poly(DEMH-TFSI) with low to high molecular weight (M̄n = 49 100-392 500) and a narrow molecular weight distribution (M̄w/M̄n = 1.17-1.46). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/marc.201300855

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography A  

The kinetic performance of commercially available first generation and prototype second generation silica monoliths has been investigated for 2.0mm and 3.0-3.2mm inner diameter columns. It is demonstrated that the altered sol-gel process employed for the production of second generation monoliths results in structures with a smaller characteristic size leading to an improved peak shape and higher efficiencies. The permeability of the columns however, decreases significantly due to the smaller throughpore and skeleton sizes. Scanning electron microscopy pictures suggest the first generation monoliths have cylindrical skeleton branches, whereas the second generation monoliths rather have skeleton branches that resemble a single chain of spherical globules. Using recently established correlations for the flow resistance of cylindrical and globule chain type monolithic structures, it is demonstrated that the higher flow resistance of the second generation monoliths can be entirely attributed to their smaller skeleton sizes, which is also evident from the external porosity that is largely the same for both monolith generations (e{open}e~0.65). The recorded van Deemter plots show a clear improvement in efficiency for the second generation monoliths (minimal plate heights of 13.6-14.1μm for the first and 6.5-8.2μm for the second generation, when assessing the plate count using the Foley-Dorsey method). The corresponding kinetic plots, however, indicate that the much reduced permeability of the second generation monoliths results in kinetic performances (time needed to achieve a given efficiency) which are only better than those of the first generation for plate counts up to N~45,000. For more complex samples (N≥50,000), the first generation monoliths can intrinsically still provide faster analysis due to their high permeability. It is also demonstrated that - despite the improved efficiency of the second generation monoliths in the practical range of separations (N=10,000-50,000) - these columns can still not compete with state-of-the-art core-shell particle columns when all columns are evaluated at their own maximum operating pressure (200bar for the monolithic columns, 600bar for core-shell columns). It is suggested that monolithic columns will only become competitive with these high efficiency particle columns when further improvements to their production process are made and their pressure resistance is raised. © 2013 Elsevier B.V.

DOI： 10.1016/j.chroma.2013.11.047

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その他リンク： http://orcid.org/0000-0002-8069-4780

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

High-performance thermal insulating materials are desired especially from the viewpoint of saving energy for a sustainable society. Aerogel is the long-awaited material for extended applications due to its excellent thermal insulating ability. These materials are, however, seriously fragile against even small mechanical stress due to their low density, and their poor mechanical properties inhibit their practical use as superinsulators. In this paper, we report relationships between the thermal conductivity, pore size and mechanical properties of organic-inorganic hybrid polymethylsilsesquioxane (PMSQ) aerogels with improved mechanical properties and controllable pore sizes from similar to 50 nm to 3 mu m. The dependency of thermal conductivity on gas pressure and pore properties can be well explained by the thermal conduction theory of porous materials. These PMSQ aerogels show improved mechanical properties due to their elastic networks, which enable easier handling compared to conventional aerogels and facile production by simple ambient pressure drying. An aerogel-like "xerogel" monolithic panel has been successfully prepared via ambient pressure drying, which shows a low thermal conductivity (0.015 W m(-1) K-1) comparable with those of the corresponding PMSQ aerogel and conventional silica aerogels. These results would open the gate for practical applications of these porous materials.

DOI： 10.1039/c3ta15094a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：RSC Advances  

Hierarchically porous layered double hydroxide (LDH) materials have potential in anion-exchange, adsorption and catalysis applications, because of their large surface areas and liquid transportation capabilities. The preparation of monolithic LDH-Al(OH)3 composites with hierarchical μm and nm-scale channels and their adsorption behavior is reported. Monolithic gels were synthesized via sol-gel processing, from metal salt precursor solutions. μm-scale macrochannels spontaneously formed by inducing phase separation during sol-gel transition. nm-scale mesochannels were accommodated as interstices between primary/secondary particles. In this study, these hierarchical channel sizes were controlled. The macrochannel size was controlled by tuning the degree of phase separation. The mesochannel size was controlled independently, by tuning the crystallite size of LDH under different solvothermal conditions. The relationship between pore characteristics and adsorption behavior of tailored hierarchically porous LDH-Al(OH)3 monolithic gels were investigated by using dye molecules as adsorbates. Monolithic gels with larger macrochannels and mesochannels exhibit faster adsorption rate and higher affinity, respectively. LDH-Al(OH)3 monolithic gels with hierarchical channels may have potential in some applications such as biosensing, water purification and catalysis. This journal is © the Partner Organisations 2014.

DOI： 10.1039/c4ra00873a

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その他リンク： http://orcid.org/0000-0002-8069-4780

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：New Journal of Chemistry  

Pore architecture of catalyst supports is an important factor facilitating accessibility of reactants to catalytic sites. This holds the key to improving catalytic activities. Amongst various catalytic reactions, supported Pd nanoparticles-catalyzed C-C cross-coupling reactions have been attracting a great deal of attention in the last decade. Although various supports have been examined, applications of hierarchically porous monolithic materials have never been reported, mainly because of difficulties in multistep synthesis of catalysts. We herein report a novel on-site reduction-based methodology using hierarchically porous hydrogen silsesquioxane (HSQ) monoliths for one-step synthesis of Pd nanoparticles-embedded monoliths (Pd@HSQ). Characterization of these monoliths evidences the on-site reduction, i.e. formation of Pd nanoparticles and conversion of Si-H present in the monolith to Si-O∼. Fast, quantitative reduction of Pd2+ to Pd(0) to form supported Pd nanoparticles is achieved with preservation of the porous structure of the original monolith, which makes this material attractive as a catalyst for C-C cross-coupling reactions. The obtained Pd@HSQ catalyst has been employed in the Mizoroki-Heck cross-coupling reaction. High accessibility of reactant molecules, undetectable leaching of Pd nanoparticles and easy separation of the monolith from liquid media provide high catalytic activity, reusability and easy handling. © 2014 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.

DOI： 10.1039/c3nj01433a

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10934-013-9733-z

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie - International Edition  

A monolithic material has marshmallow-like flexibility and superamphiphobic properties on any cutting surface. The two-step synthesis consists of a simple sol-gel process to obtain vinyl-modified superhydrophobic monolithic gels and grafting of perfluoroalkyl groups onto the pore surface to decrease surface energy. These superamphiphobic materials float on water and even on organic liquids with low polarity, such as alkanes. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/anie.201304169

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/la402205j

PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

In this report, we demonstrate a novel synthesis method to obtain reduced titanium oxides with monolithic shape and with a well-defined hierarchically porous structure from the titanium-based network bridged with ethylenediamine. The hierarchically porous monoliths are fabricated by the nonhydrolytic sol-gel reaction accompanied by phase separation. This method allows a low-temperature crystallization into Ti4O7 and Ti3O5 at 800 and 900 C, respectively, with N-doped carbon. These reduced titanium oxides are well-doped with N atoms even under argon atmosphere without NH 3, which accounts for the low-temperature reduction. The resultant monolithic materials possess controllable macropores and high specific surface area together with excellent electric conductivity up to 230 S cm-1, indicating promise as a conductive substrate that can substitute carbon electrodes. © 2013 American Chemical Society.

DOI： 10.1021/cm401933a

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jeurceramsoc.2013.02.018

Web of Science

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10971-013-3123-5

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10971-013-3094-6

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Microporous and Mesoporous Materials  

Utilizing a facile sol-gel reaction accompanied by phase separation, rigid monolithic nickel hydroxide-based xerogels and nickel/carbon composites with hierarchical porosity have been successfully fabricated. In the synthetic route starting from nickel chloride as a nickel precursor, trimethylene oxide acts as a gelation initiator to increase pH in a reaction solution. In addition, poly(acrylic acid) plays a double role as a phase separation inducer and as a co-constituent with nickel hydroxide to comprise continuous gel skeletons in the micrometer range. As a result, obtained xerogels possess well-defined macropores evidenced by microscopy observation and mercury porosimetry. Subsequent heat-treatment in air led to the crystallization of NiO at 300 C, while calcination under argon flow brought about the formation of nickel/carbon (Ni/C) composites with hierarchical pores and large specific surface area at temperatures higher than 300 C. This is the first report on the preparation of rigid monolithic xerogels and metal/carbon composite with well-defined macropores based on a metal salt precursor containing "divalent" cation. © 2013 Elsevier B.V.All rights reserved.

DOI： 10.1016/j.micromeso.2013.03.042

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1088/1468-6996/14/4/045007

PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Separation Science  

Reproducible fabrication of the hierarchically porous monolithic silica in a large volume exceeding 1000 mL has been established. By the hydrothermal enlargement of the fully accessible small pores to exceed 50 nm in diameter, the capillary force emerged on solvent evaporation was dramatically reduced, which allowed the preparation of crack-free monoliths with evaporative solvent removal under an ambient pressure. The local temperature inhomogeneity within a reaction vessel in a large volume was precisely controlled to cancel the heat evolved by the hydrolysis reaction of tetramethoxysilane and that consumed to melt ice cubes dispersed in the solution, resulting in large monolithic silica pieces with improved structural homogeneity. Homogeneity of the pore structure was confirmed, both on macro- and mesoscales, using SEM, mercury intrusion, and nitrogen adsorption/desorption measurements. Furthermore, the deviations in chromatographic performance were examined by evaluating multiple smaller monolithic columns prepared from the monolithic silica pieces cut from different parts of a large monolith. All the daughter columns thus prepared exhibited comparable performances to each other to prove the overall homogeneity of the mother monolith. Preliminary results on high-speed separation of peptides and proteins by the octadecylsilylated silica monolith of the above production have also been demonstrated. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/jssc.201300123

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/am303163s

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Wuli Huaxue Xuebao/ Acta Physico - Chimica Sinica  

Macroporous SiO2 monoliths were prepared via a sol-gel process accompanied by phase separation using a tetramethoxysilane (TMOS) precursor, 0.01 mol·L-1 HCl catalyst, propylene oxide (PO) gelation agent, and poly(ethylene oxide) (PEO, viscosity-averaged molecular weight (Mv): 10000) phase separation inducer. Monoliths were characterized by differential thermal analysis/thermogravimetry (DTA/ TG), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), mercury porosimetry, and nitrogen adsorption/desorption analysis (BET). The mechanism of the epoxide-mediated sol-gel reaction and PEO induced phase separation was discussed. The addition of PEO induced phase separation, and monolithic SiO2 with a cocontinuous macroporous skeletal structure was obtained at PEO/TMOS molar ratio of 0.0018. Monoliths had a narrow pore size distribution of 1-3 μm, surface area as high as 719 m2·g-1 and pore volume of 0.48 m3·g-1. This sol-gel transition is mediated by PO because of its strong nucleophilic properties and irreversible ring-opening reaction. Simultaneous phase separation is induced by PEO adsorbed on the SiO2 oligomers. © Editorial office of Acta Physico-Chimica Sinica.

DOI： 10.3866/PKU.WHXB201212252

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie - International Edition  

Soaking up s'more: Marshmallow-like flexible gels synthesized from organoalkoxysilanes by a facile process show superior oil/water separation properties. The gels are superhydrophobic and can be used to remove organic compounds from water through absorption; they can then be recovered by squeezing them out of the gel, as if it were a sponge. The gel retains flexibility over a wide temperature range, even in liquid nitrogen (see photo). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/anie.201207969

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Physical Chemistry Chemical Physics  

Monolithic Li2FeSiO4-carbon composites with well-defined macropores have been prepared from the silica-based gels containing Li, Fe, and carbon sources. The macroporous precursor gels can be fabricated by the sol-gel method accompanied by phase separation. A fine control of the macropore size in the resultant composites has been achieved by controlling the macropore size of the precursor gels simply by adjusting the starting compositions. The effects of pore properties on Li insertion-extraction capabilities have been investigated by utilizing the resultant Li 2FeSiO4-carbon composites as the cathode of lithium ion batteries. The electrodes prepared from the Li2FeSiO 4-carbon composites with different macropore sizes exhibit significant differences in the charge-discharge properties. The results strongly suggest that the smaller macropore size (equal to the thinner macropore skeletons) and the presence of micro- and mesopores in the macropore skeletons (hierarchically porous structure) are desirable for a better electrode in the case of Li2FeSiO4, which has extremely low ionic and electrical conductivities. © 2013 The Owner Societies.

DOI： 10.1039/c3cp50352f

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c3ra22481c

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c3ra90142d

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

DOI： 10.1039/c3ra90142d

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Materials Chemistry A  

Monolithic layered double hydroxides (LDHs) with interconnected channels have been expected to enhance sorption rate as well as increase accumulation of anions. Although powder molding can form easily-handled LDH compacts, interconnected channel formation therein has not been achieved. Herein, we demonstrate cm-scale monolithic LDH-based composites with interconnected hierarchical channels via a spontaneous sol-gel reaction. The synthesis was performed on Mg-Al hydrotalcite-type LDHs starting from metal chlorides aqueous/ethanolic solution with poly(ethylene oxide) incorporated. Addition of propylene oxide triggers a sol-gel reaction to form monolithic xerogels with a formula of [Mg0.66Al0.33(OH)2Cl 0.33·2.92H2O]·3.1Al(OH)3. LDH crystals together with aluminum hydroxide crystals homogeneously build up gel skeletons with well-defined hierarchical channels. The interconnected channel in μm range (macrochannel) are formed as a phase-separated structure, whereas the channel in nm range (nanochannel) are as interstices of primary particles. The channel architectures are preserved in the course of rehydration process, affording enhanced sorption affinity for anion species in the process. Both of macro and mesochannels as well as high charge density of the obtained LDHs (Mg/Al = 2.0) contribute to enhanced anion sorption in the monolithic xerogels. The materials obtained here opens up applications of high performance adsorbents and ion-storage free from diffusion limitation. © 2013 The Royal Society of Chemistry.

DOI： 10.1039/c3ta11110e

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：RSC Advances  

We report an electrically conducting oxygen-deficient anatase TiO 2-x monolith with macro/meso/micro trimodal pores, prepared by reducing insulating porous TiO2 monoliths at low temperature. Without adding any conductive materials, the TiO2-x monolith itself was electrically conducting enough for lithium insertion, potentially opening a new avenue for carbon-free electrode materials. © The Royal Society of Chemistry 2013.

DOI： 10.1039/c3ra40545a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Physical Chemistry C  

The effects of the pore properties and the ionic sizes on the electric double-layer capacitances have been investigated by using the monolithic carbon electrodes with different pore properties. The carbon monoliths with high surface areas which possess homogeneous pore properties in the whole monoliths were prepared from the bridged-polysilsesquioxane gels via the nanophase extraction technique. The detailed investigations of the pore properties of the carbon monoliths were conducted by the nitrogen physisorption measurement as well as the mercury porosimetry. The electrochemical property of each monolithic carbon electrode was examined by the cyclic voltammetry in the different aqueous electrolytes in order to investigate the effects of the ionic sizes. These fundamental analyses have provided new insights into the efficient micropore sizes in each electrolyte for the superior electric double-layer capacitors. © 2012 American Chemical Society.

DOI： 10.1021/jp309010p

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ja302083n

PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/cm300495j

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials Letters  

In this report, we demonstrate the facile preparation of macroporous monolithic materials based on graphitized carbon by utilizing catalytic graphitization at relatively low temperature (1000°C). The precursor polymer, macroporous resorcinol-formaldehyde (RF) xerogel, can be obtained without any surfactants or polymeric additives in water/ethanol mixed solvent via the sol-gel reaction accompanied by phase separation. The use of iron chloride as an acid catalyst for polymerization provides the RF monoliths incorporated with Fe, which catalyzes the graphitization. The effects of the starting composition on the morphologies of the resultant RF gels and the characteristics of the graphitized carbon monoliths have been discussed. © 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2012.02.069

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

Organosiloxane (RnSiO(4-n)/2) gels can be prepared from organoalkoxysilanes using the sol-gel process. In general,however, formation of uniform networks from these precursors is strongly inhibited due to cyclization reactions. In addition, phase separation of hydrophobic condensates from polar solvent leads to inhomogeneous gels in these systems. A careful control of the hydrolysis and polycondensation reactions is therefore required to obtain a monolithic gel with desired properties. We have been trying to control the sol-gel reactions as well as phase separation in these systems to obtain unique porous materials particularly from methyltrimethoxysilane(MTMS) and dimethyldimethoxysilane (DMDMS). Flexible aerogels and xerogels based on the methylsiloxane networks are discussed.

DOI： 10.2497/jjspm.59.320

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Colloid and Interface Science  

Surface modification of titania materials to give flower-like structures has been achieved simply by the treatment in lithium hydroxide aqueous solution under mild conditions. The flower-like structured materials were characterized by X-ray diffraction, thermogravimetric analysis, and Raman scattering. The analyses indicate that the flower-like materials are composed of layered hydrous lithium titanate. It is suggested that the unique intercalation behavior of lithium ions into titania allows dissolution and re-precipitation of titania to form the flower-like structure. The obtained flower-like structure can be retained up to 700°C, while the crystal phase transforms into Li 4Ti 5O 12. © 2012 Elsevier Inc.

DOI： 10.1016/j.jcis.2012.02.002

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Applied Materials and Interfaces  

Macroporous polymer monoliths based on poly(styrene-co-divinylbenzene) with varied styrene/divinylbenzene ratios have been prepared by organotellurium- mediated living radical polymerization. The well-defined cocontinuous macroporous structure can be obtained by polymerization-induced spinodal decomposition, and the pore structures are controlled by adjusting the starting composition. The separation efficiency of small molecules (alkylbenzenes) in the obtained monoliths has been evaluated in the capillary format by high-performance liquid chromatography (HPLC) under the isocratic reversed-phase mode. Baseline separations of these molecules with a low pressure drop (∼2 MPa) have been achieved because of the well-defined macropores and to the less-heterogeneous cross-linked networks. © 2012 American Chemical Society.

DOI： 10.1021/am300552q

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

エアロゲルの力学的強度を改善するため、非反応性のメチル基により柔軟性や低い架橋密度を実現した有機-無機ハイブリッドエアロゲルがこれまでに研究されてきた。本研究においては3官能性ケイ素アルコキシドmethyltrimethoxysilane (MTMS) と2官能性アルコキシドdimethyldimethoxysilane (DMDMS) を前駆体、<I>n</I>-hexadecyltrimethylammonium chloride (CTAC) を相分離抑制のための界面活性剤として用い、酢酸と尿素を使った酸性/塩基性触媒による2段階ゾル－ゲル反応でエアロゲルを合成することに成功している。この出発組成を変化させることでエアロゲルの微細構造や結合を制御し、密度・力学特性の変化を調べた。

DOI： 10.14853/pcersj.2012S.0.280.0

記述言語：英語   掲載種別：研究論文（学術雑誌）  

掲載種別：研究論文（学術雑誌）  

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掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Polymer Science  

By combining the micellar templating in nanometer scale with the polymerization-induced phase separation in micrometer scale, ethylene-bridged polysilsesquioxane gels with hierarchical macropores and mesopores are prepared. The difference of mesopore structures depending on the method of the solvent removal has been observed by the X-ray diffraction and the nitrogen adsorption-desorption measurements. During the hydrothermal treatment under the basic condition, the reorganization of the polysilsesquioxane gel network occurred differently depending on the alkoxy group contained in the precursors. From 29Si CP/MAS NMR measurements, it was revealed that the crosslinking density of the hydrothermally treated gels was increased so that the highly ordered mesostructure of the wet gel could be preserved even after the evaporative drying of solvent. © 2012 Atsushi Mushiake et al.

DOI： 10.1155/2012/460835

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10971-012-2790-y

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本セラミックス協会  

細孔特性の精密な制御が可能な相分離法によって，細孔サイズが一様で，連続したマクロ孔をもつシリカやアルミナ，チタニアなどのマクロ多孔性酸化物モノリス体が得られているが、従来の報告は全て絶縁体であった．我々は相分離法により得られたTiO<SUB>2</SUB>のマクロ多孔性モノリス体に対して，金属ジルコニウムを用いた還元反応を行い，一連の酸素欠損型チタン酸化物Ti<SUB><I>n</I></SUB>O<SUB>2<I>n</I>－1</SUB> (<I>n</I> = 2, 3, 4, 6)のマクロ多孔性モノリス体をそれぞれ単相で作製した．得られた一連の還元体はTiO<SUB>2</SUB>前駆体の孔特性をほぼ完全に維持している．また従来の約半分のバルク密度(1.8 g cm<SUP>－3</SUP>)，約3倍の空孔率(60%)，そして同等の室温バルク抵抗率(2 × 10<SUP>－2</SUP> Ω cm)を有しており，様々な電極材料としての応用が考えられる．

DOI： 10.14853/pcersj.2012S.0.526.0

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

A novel and facile method for the preparation of monolithic LiFePO 4/carbon composites with well-defined macropores has been developed. The precursor macroporous gels consisting of inorganic networks as well as organic polymers were fabricated by the epoxide-mediated sol-gel method accompanied by phase separation. The inorganic-organic hybrid gels were calcined under an inert atmosphere, resulting in LiFePO4/carbon monoliths. The influence of the starting compositions on the gel morphologies has been investigated, and the constituents of the gel network were discussed. The reaction mechanism of the crystallization of LiFePO4 from green bodies during calcination has also been investigated by thermal analysis, X-ray diffraction, and Raman scattering. In addition, the electrochemical properties of the resultant LiFePO4/carbon composites were examined by the charge-discharge test. © 2011 American Chemical Society.

DOI： 10.1021/cm2021438

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Materials Research Society Symposium Proceedings  

Macro/meso/microporous carbon monoliths doped with sulfur have been prepared from sulfonated polydivinylbenzene networks followed by the activation with CO 2 resulted in the activated carbon monoliths with high surface area of 2400 m 2 g -1. The monolithic electrode of the activated carbon shows remarkably high specific capacitance (175 F g -1 at 5 mV s -1 and 206 F g -1 at 0.5 A g -1). © 2011 Materials Research Society.

DOI： 10.1557/opl.2011.604

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Materials Research Society Symposium Proceedings  

A transition of porous structures in monolithic poly(methylsilsesquioxane) (PMSQ, CH 3SiO 1.5) gels from uniform mesopores to hierarchical pore structures consisting of macro- and mesopores, has been investigated using a sol-gel system containing surfactant Pluronic F127. A broad variation of porous morphology is controlled by changing the concentration of F127. Sufficient concentrations of F127 inhibit the occurrence of macroscopic phase separation of hydrophobic PMSQ condensates and lead to well-defined mesoporous transparent aerogels with high specific pore volume. Mesopores are developed through microscopic phase separation of PMSQ colloid-surfactant complexes in the solvent. Macroscopic phase separation regulates well-defined macropores in the micrometer range on decreasing concentrations of F127, in which microscopic phase separation concurrently takes place in the PMSQ-rich gelling phase after the onset of macroscopic phase separation. Monolithic PMSQ gels with hierarchical macro- and mesopore structures are consequently obtained. © 2011 Materials Research Society.

DOI： 10.1557/opl.2011.96

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Wiley-VCH  

DOI： 10.1002/9783527639588.ch8

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Wiley-VCH  

DOI： 10.1002/9783527639588.ch17

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Separation Science  

Separation media based on hierarchically porous titania (TiO2) monoliths for highperformance liquid chromatography (HPLC) have been successfully fabricated by the sol-gel process of titanium alkoxide in a mild condition utilizing a chelating agent and mineral salt. The as-gelled TiO 2 monoliths were subjected to a simple solvent exchange process from ethanol (EtOH) to H2O followed by drying and calcination. The resultant monolithic TiO2 columns consist of anatase crystallites with the typical specific surface area of more than 200m2/g. The resultant monolithic TiO2 column calcined at 200 and 400°C exhibited a good separation performance for organophosphates as well as for polar benzene derivatives in the normal-phase mode. © 2011 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim.

DOI： 10.1002/jssc.201100538

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その他リンク： http://orcid.org/0000-0002-8069-4780

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer  

Rigid methacrylate-based polymer monoliths with well-defined macropores have been synthesized from glycerol 1,3-dimethacrylate (GDMA) and trimethylolpropane trimethacrylate (Trim) by organotellurium-mediated living radical polymerization. In each system, poly(ethylene oxide) induced spinodal decomposition with the progress of polymerization of GDMA or Trim. Well-defined macroporous structure can be tailored by fixing the bicontinuous structure by the sol-gel transition. Both polymer monoliths possessed macropores with narrow size distributions and the macropore size can be controlled simply by varying the amount of poly(ethylene oxide). Starting from GDMA, polymer monoliths with unimodal macropores can be obtained due to the collapse of micro- and mesopores, which were originally embedded in macropore skeletons, by large shrinkage during drying. In contrast, starting from Trim, the obtained polymer monoliths include not only macropores but also micro- and mesopores, which lead to high specific surface area (470 m2 g-1), owing to the higher crosslinking density. © 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2011.08.028

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the Ceramic Society of Japan  

In this study, we for the first time came up with a facile approach to fabricate hierarchically porous nano-crystalline monolithic magnesium titanates (MgTi2O5/MgTiO3) by impregnating magnesium chloride into hierarchically porous TiO2 monolith in a solution containing urea followed by appropriate heat-treatment. The formation of porous MgTi2O5/MgTiO3 monolithic materials took place by the solid-state reaction between original TiO2 networks and precipitated MgCO3. The MgCO3 is precipitated within the TiO2 wet gel by the reaction between impregnated Mg2+ and CO2, which is produced by hydrolysis and decarbonation of chelating agent in the TiO2 wet gels and by the hydrolysis of urea at 60°C. The resultant porous magnesium titanates retained narrow macropore size distribution centered at the diameter ̃1 μm. These porous monoliths produced by impregnation, a facile and the low-cost method, are expected to open various engineering applications owing to the low thermal expansion coefficients and high chemical and physical stabilities. © 2011 The Ceramic Society of Japan.

DOI： 10.2109/jcersj2.119.440

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.chroma.2010.10.045

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jcis.2011.02.027

PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography A  

Chromatographic properties of a new type of monolithic silica rod columns were examined. Silica rod columns employed for the study were prepared from tetramethoxysilane, modified with octadecylsilyl moieties, and encased in a stainless-steel protective column with two polymer layers between the silica and the stainless-steel tubing. A 25cm column provided up to 45,000 theoretical plates for aromatic hydrocarbons, or a minimum plate height of about 5.5μm, at optimum linear velocity of ca. 2.3mm/s and back pressure of 7.5MPa in an acetonitrile-water (80/20, v/v) mobile phase at 40°C. The permeability of the column was similar to that of a column packed with 5μm particles, with K F about 2.4×10 -14m 2 (based on the superficial linear velocity of the mobile phase), while the plate height value equivalent to that of a column packed with 2.5μm particles. Generation of 80,000-120,000 theoretical plates was feasible with back pressure below 30MPa by employing two or three 25cm columns connected in series. The use of the long columns enabled facile generation of large numbers of theoretical plates in comparison with conventional monolithic silica columns or particulate columns. Kinetic plot analysis indicates that the monolithic columns operated at 30MPa can provide faster separations than a column packed with totally porous 3-μm particles operated at 40MPa in a range where the number of theoretical plates (N) is greater than 50,000. © 2010 Elsevier B.V.

DOI： 10.1016/j.chroma.2010.11.032

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10971-010-2184-y

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Wiley-VCH  

DOI： 10.1002/9783527633241.ch5

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Wiley-VCH  

DOI： 10.1002/9783527633241.ch2

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IOP Conference Series: Materials Science and Engineering  

Porous gel monolith was synthesized by reacting (3-mercaptopropyl) trimethoxysilane (MPTMS) with acetone on acidic conditions. It is known that MPTMS itself is difficult to turn into gel on acidic conditions and instead oligomers are obtained owing to the large mercaptopropyl group. In our system, the gels were obtained since acetone worked as a cross-linker via thioacetal reaction. Additionally, Au ions were selectively adsorbed on the obtained gel. When an obtained white gel was soaked in a chloroauric acid solution, the gel turned brown and was getting dark depending on the soaked time; on the other hand, the color of the solution turned from yellow to colorless. © 2011 Ceramic Society of Japan.

DOI： 10.1088/1757-899X/18/3/032003

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その他リンク： http://orcid.org/0000-0002-8069-4780

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Society Reviews  

Porous polysilsesquioxane gels derived from sol–gel systems based on trifunctional silanes are reviewed. Although it is well known that trifunctional silanes possess inherent difficulties in forming homogeneous gels, increasing attention is being paid on these precursors and resultant porous polysilsesquioxanes because of hydrophobicity, functionality, and versatile mechanical properties. Much effort has been made to overcome the difficulties for homogeneous gelation, and a number of excellent porous materials with various pore properties have been explored. In this critical review, we put special emphasis on the formation of a well-defined macroporous structure by making use of phase separation, which in turn is a serious problem in obtaining homogeneous gels though. Porous polysilsesquioxane monoliths with the hierarchical structure and transparent aerogels with high mechanical durability are particularly highlighted (169 references). © 2011 The Royal Society of Chemistry.

DOI： 10.1039/c0cs00068j

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1088/1757-899X/18/3/032001

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IOP Conference Series: Materials Science and Engineering  

Hierarchically porous carbon monoliths with high specific surface areas have been fabricated by removing nano-sized silica phase from carbon/silica composites pyrolyzed from bridged poly(silsesquioxane). This activation method improves the homogeneity between inner and outer parts of the monoliths compared to the conventional thermal activation methods. © 2011 Ceramic Society of Japan.

DOI： 10.1088/1757-899X/18/3/032005

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その他リンク： http://orcid.org/0000-0002-8069-4780

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1088/1757-899X/18/3/032013

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Recent years, although silica aerogels are expected to be the promising material for energy savings, the lack of mechanical strength prevents from commercial applications such as to low-density thermal insulators. To improve mechanical properties, methyltrimethoxysilane (MTMS) and dimethyldimethoxysilane (DMDMS) are used in this study as the co-precursor of aerogels because the network becomes flexible due to the relatively low cross-linking density and to the unreacted methyl groups. Because of the strong hydrophobicity of MTMS/DMDMS-derived condensates, phase separation occurs in aqueous sol and must be suppressed to obtain uniform and monolithic gel. We employed surfactant n-hexadecyltrimethylammonium chloride (CTAC) in starting compositions to control phase separation during a 2-step acid/base sol-gel reaction. By changing the starting composition, various microstructures of pores are obtained. In the uniaxial compression test, the aerogel showed high flexibility and spring-back to the original shape after removing the stress. © 2011 Materials Research Society.

DOI： 10.1557/opl.2011.216

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Materials Chemistry  

Macro/meso/microporous carbon monoliths doped with sulfur have been prepared from sulfonated poly(divinylbenzene) networks followed by the activation with CO2 resulted in the activated carbon monoliths with high surface area of 2400 m2 g-1. The monolithic electrode of the activated carbon shows remarkably high specific capacitance (175 F g-1 at 5 mV s-1 and 206 F g-1 at 0.5 A g-1). © The Royal Society of Chemistry.

DOI： 10.1039/c0jm03793a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Materials Chemistry  

We report new flexible "marshmallow-like" aerogels and xerogels with a bendable feature from the methyltrimethoxysilane (MTMS) and dimethyldimethoxysilane (DMDMS) co-precursor systems. A 2-step acid/base sol-gel process and surfactant are employed to control the phase separation of the hydrophobic networks, which give porous monolithic gels. The obtained gels become softer and more flexible with increasing DMDMS fractions. © 2011 The Royal Society of Chemistry.

DOI： 10.1039/c1jm13664j

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Colloid and Interface Science  

The structure formation process of hierarchically porous alumina gels has been investigated by in situ small angle X-ray scattering (SAXS). The measurement was performed on the sol-gel solution containing aluminum chloride hexahydrate (AlCl3·6H2O), poly(ethylene oxide) (PEO), and propylene oxide (PO). The temporal divergence of scattering intensity in the low q regime was observed in the early stage of reaction, indicating that the occurrence of spinodal-decomposition-type phase separation. Detailed analysis of the SAXS profiles revealed that phase separation occurs between weakly branched polymerizing aluminum hydroxide (AH) and PEO. Further progress of the condensation reaction forms phase-separated two phases, that is, AH-rich phase and PEO-rich phase with the micrometer-range heterogeneity. The growth and aggregation of primary particles occurs in the phase-separated AH-rich domain, and therefore, the addition of PEO influences on the structure in nanometer regime as well as micrometer regime. The moderate stability of oligomeric species allows homogeneous condensation reaction parallel to phase separation and successful formation of hierarchically porous alumina gel. © 2010 Elsevier Inc.

DOI： 10.1016/j.jcis.2010.08.041

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Ceramic Society  

Monolithic titania (TiO2) with multiscale porous structures have been successfully prepared via the sol-gel route accompanied by phase separation utilizing a chelating agent and mineral salt. The TiO2 gels obtained possess well-defined macropores derived from spinodal decomposition and mesopores as interstices of anatase TiO2 nanocrystallites.Most of the chelating agent were removed by hydrolysis and subsequent decarbonation through the gradual solvent exchange from ethanol to water. The TiO2 particles comprising TiO2 gel skeletons spontaneously converted from amorphous to anatase through the solvent exchange process in a mild condition at 60°C. The present method of the fabrication of porous TiO2 monoliths is advantageous for widespread applications because the reaction occurs under an almost neutral condition and does not require a hydrothermal process, which was indispensable to strengthen the monolith in the method previously reported © 2010 The American Ceramic Society.

DOI： 10.1111/j.1551-2916.2010.03831.x

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.micromeso.2010.04.005

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Carbon  

Poly(divinylbenzene) (PDVB) monoliths with well-defined macropores that have been sulfonated and carbonized to obtain macroporous carbon monoliths. The original macroporous PDVB networks have been synthesized by living radical polymerization accompanied by spinodal decomposition. Sulfonation prevents polymer networks from large shrinkage and weight loss during carbonization by heat-treatment in an inert atmosphere. In the case of PDVB gels sulfonated at 120 °C using conc. H2SO4, mesopores in the original skeletons as well as macropores are retained after carbonization. The obtained carbon monoliths are subsequently activated by CO2, which resulted in activated carbons. The specific surface area of the obtained activated carbons reaches up to 2360 m2 g-1. © 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.carbon.2010.01.019

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その他リンク： http://orcid.org/0000-0002-8069-4780

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

Macroporous polysilsesquioxane monoliths have been synthesized from biphenylene-bridged alkoxysilane via the sol-gel transition and concurrent phase separation both induced by the polycondensation reaction. The obtained polysilsesquioxane gels have been subsequently converted to macroporous SiC/C composites by the carbothermal reduction. The SiC/C monoliths thus obtained involve no visible cracks and their porosity reaches as high as >90%. In addition, according to the nitrogen adsorption-desorption measurement results, the micro- and mesopore characteristics of the samples did not undergo a significant change during the carbothermal reduction and the SiC/C composites have large specific surface areas owing to the microporous carbons in the skeletons. These composites therefore are more suitable for the applications to gas storage and catalyst supports compared to pure SiC. © 2010 American Chemical Society.

DOI： 10.1021/cm9034616

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Highly homogeneous transparent titania gels have been successfully prepared from titanium alkoxide by a sol-gel method utilizing chelating agent, ethyl acetylacetate (EtAcAc), in the presence of strong acid anions. Only catalytic amount of a strong acid anion suppress the rapid hydrolysis of titanium alkoxide by blocking the nucleophilic attack of HO- and H2O, and the resultant moderate sol-gel reactions thus afford homogeneous gelation, leading to transparent monolithic titania gels. Gelation time can be widely controlled by changing amounts of water, chelating agent and salt. The ability of salts to suppress the too abrupt sol-gel reactions is strongly dependent on the electronegativity of anions and valence of cations. With employing NH 4NO3 as a suppressing electrolyte, the obtained titania gels can be converted to pure TiO2 by simple washing and heat-treatment, and transformations to anatase and rutile structures were found to start at 400 and 600 °C, respectively. © 2009 Springer Science+Business Media, LLC.

DOI： 10.1007/s10971-009-2056-5

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Communications  

Hierarchically porous carbon monoliths with high specific surface areas have been fabricated by removing nano-sized silica phase from carbon/silica composites pyrolyzed from bridged polysilsesquioxane. This activation method improves the homogeneity between inner and outer parts of the monoliths compared to the conventional thermal activation methods. © 2010 The Royal Society of Chemistry.

DOI： 10.1039/c0cc02974b

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Comptes Rendus Chimie  

Carbon monoliths with well-defined macropores and high surface areas were prepared by carbonization of macroporous poly(divinylbenzene) (PDVB) monoliths. The carbonization reactions of PDVB networks are studied by thermal analysis and FT-IR measurements. According to the measurement results, the PDVB networks are mostly pyrolyzed at 430 °C and their structures dynamically change to graphite-like structure between 600 and 700 °C. The macropore structure retained while the mesopores disappeared after carbonization. In addition, the surface area of the obtained carbons dramatically increased over 900 °C. The typical carbon monolith carbonized at 1000 °C for 2 h had a surface area of 1500 m2 g-1 and uniform macropores with a diameter of 1 μm. © 2009 Académie des sciences.

DOI： 10.1016/j.crci.2009.04.003

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2109/jcersj2.117.1333

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.chroma.2009.05.028

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PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.chroma.2009.06.016

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jcis.2009.06.042

PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jssc.200800653

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/marc.200900066

PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the Ceramic Society of Japan  

Porous alumina monoliths with high thermal stability have been prepared using sol-gel processing from ionic precursors. Samples were synthesized from AlCl3·6H2O and LaCl3·7H 2O dissolved in a H2O/etanol solution containing poly(ethylene oxide) (PEO) via propylene oxide (PO) involved sol-gel reaction accompanied by phase separation. The heat-treated gels consist of controllable size of macropores and La-doped alumina skeletons. Doped lanthanum ions are homogeneously embedded in the gel matrix, which retards the phase transition from γ -alumina to α -alumina during the sintering. The 3 mol% La-doped aluminate exhibits the BET surface area of 55.3 m2/g, after the heat treatment at 1100°C for 24 h. Drying condition are also related to the thermal stability of obtained gels. Aluminate aerogels show higher thermal stability than corresponding xerogels due to relatively large mesopore size and high porosity. As a result, the 3 mol% lanthanum doped aluminate aerogel shows BET surface area as high as 82.5 m2/g even after heat treatment at 1100°C for 24 h. © 2009 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.117.351

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/b903444g

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：MATERIALS RESEARCH SOC  

Transparent organic-inorganic hybrid aerogels and aerogel-like xerogels have been prepared from methyltrimethoxysilane (MTMS) respectively by supercritical drying (SCD) and ambient pressure drying (APD). The new aerogels and xerogels significantly deform without collapsing on uniaxial compression and almost fully relax when unloaded. This elastic behavior., termed as "spring-back", allows APD without noticeable shrinkage and cracking. The flexible network composed of lower cross-linking density (up to three bonds per every silicon atom) compared to silica gels (up to four bonds) and repulsion between hydrophobic methyl groups bonded to every silicon atom largely contributes to the pronounced deformability and relaxing, respectively. Lower surface silanol group density also plays a crucial role for the "spring-back" behavior.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：MATERIALS RESEARCH SOC  

Macroporous cross-linked polymeric dried gels have been obtained by inducing phase separation in a homogeneous poly(divinylbenzene) (PDVB) network formed by organotellurium-mediated living radical polymerization (TERP). The living polymerization reaction of DVB with the coexistence of a non-reactive polymeric agent, poly(dimethylsiloxane) (PDMS), in solvent 1,3,5-trimethylbenzene (TMB) resulted in polymerization-induced phase separation (spinodal decomposition), and the transient structure of spinodal decomposition has been frozen by gelation. Well-defined macroporous monolithic dried gels with bicontinuous structure in the micrometer scale are obtained after removing PDMS and TMB by simple washing and drying. The properties of the macropores have been controlled by changing starting composition.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：MATERIALS RESEARCH SOC  

Macroporous cross-linked polymeric dried gels have been obtained by inducing phase separation in a homogeneous poly(divinylbenzene) (PDVB) network formed by organotellurium-mediated living radical polymerization (TERP). The living polymerization reaction of DVB with the coexistence of a non-reactive polymeric agent, poly(dimethylsiloxane) (PDMS), in solvent 1,3,5-trimethylbenzene (TMB) resulted in polymerization-induced phase separation (spinodal decomposition), and the transient structure of spinodal decomposition has been frozen by gelation. Well-defined macroporous monolithic dried gels with bicontinuous structure in the micrometer scale are obtained after removing PDMS and TMB by simple washing and drying. The properties of the macropores have been controlled by changing starting composition.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Materials Chemistry  

Macroporous SiC ceramics were obtained from porous phenyl-bridged polysilsesquioxane prepared by a sol-gel method accompanied by spinodal decomposition subsequently subjected to intramolecular carbothermal reduction. By this method, we can obtain macroporous SiC ceramics with improved atomic-level homogeneity and controlled pore size more easily than by intermolecular carbothermal reduction using a mixture of SiO2 and carbon powder. Therefore, the resultant SiC ceramics have sufficiently high purity without washing with hydrofluoric acid to remove residual SiO 2. © The Royal Society of Chemistry 2009.

DOI： 10.1039/b913992c

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

By inducing phase separation parallel to the sol-gel transition of alkoxy-derived silica systems, silica monoliths with well-defined co-continuous macropores were obtained from the systems containing anionic surfactants.We adopted three kinds of anionic surfactants which differ from each other in the length of alkyl chain (CH3(CH2)i7SO3Na, CH 3(CH2)i5SO3Na, CH3(CH 2)i3SO3Na).Mesopores were also found in the silica skeletons presumably by the supramolecular templating.Characterization of the dried or heat-treated samples was carried out by a scanning electron microscope (SEM) and nitrogen adsorption measurements.Experimental results showed that due to the moderate interaction between silica oligomers and surfactants, most of the surfactants are distributed to the solvent phase which determines the macropore volume.The median size and volume of the macropores could be controlled independently by the starting composition.In the absence of any additive to enhance templating by the surfactant, the samples exhibited only amorphous mesopores. © 2008 Materials Research Society.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Novel aerogels and xerogels with methylsilsesquioxane (MSQ, CH 3SiO1.5) networks have been prepared by a modified sol-gel process using surfactant and urea as a phase-separation inhibitor and as an accelerator for the condensation reaction, respectively. Optimized aerogels dried under a supercritical condition not only showed the similar properties as conventional pure silica aerogels such as high transparency and porosity etc, but also demonstrated outstanding mechanical strength against compression; the aerogel drastically shrank upon loading and then recovered when unloaded, which is called a "spring-back" behavior. On ambient pressure drying, the wet gel also exhibited the similar response against compression stress originated from the capillary pressure, and thus xerogels with the comparative structure and properties to those of corresponding aerogels have also been obtained. This unusual mechanical behavior is attributed to the trifunctional flexible networks of MSQ, low silanol concentration which prevents the irreversible shrinkage, and high concentration of a hydrophobic methyl group directly attached to every silicon atom which helps re-expansion after the temporal shrinkage. © 2008 Springer Science+Business Media, LLC.

DOI： 10.1007/s10971-008-1756-6

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecules  

Macroporous cross-linked organic polymer monoliths with well-defined bicontinuous structure have been synthesized from 1,3-glycerol dimethacrylate (GDMA) in a solvent utilizing atom transfer radical polymerization (ATRP). With the addition of an adequate polymeric agent, poly(ethylene oxide) (PEO), spinodal decomposition was induced in the course of polymerization of GDMA. A homogeneous gelation by ATRP solidified the temporal biphasic morphology of spinodal decomposition, resulting in well-defined macroporous gels after drying. Macroporous dried gels obtained in this way comprise interconnected skeletons and macropores, which is characteristic for spinodal decomposition. Macropore size and volume were controlled simply by altering the starting composition. The mechanism of spinodal decomposition is deduced that the separation takes place between polymerizing GDMA and PEO, but FTIR and thermal analyses suggested the amount of PEO that is distributed in GDMA-rich phase cannot be neglected. Free radical polymerization, which is generally utilized for synthesis of porous polymeric gels, usually leads to heterogeneous cross-linking forming local microgels and hinders the occurrence of spinodal decomposition in a cross-linking system over extended length scales. On the other hand, living polymerization allowed homogeneous cross-linking; hence, isotropic spinodal decomposition was induced in the copresence of PEO. The facile synthesis method presented here will lead to more precise control of pore properties of cross-linked organic polymer gels. © 2008 American Chemical Society.

DOI： 10.1021/ma800563p

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.2955830

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.tsf.2007.08.012

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.chroma.2008.02.029

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Titania (TiO2) monoliths with well-defined bicontinuous macropores and gel skeletons were prepared through the alkoxy-derived sol-gel process accompanied by spinodal decomposition, and the structural evolution during evaporation drying and heat treatment was probed by a combination of ultra-small-angle X-ray scattering and small-angle X-ray scattering. X-ray scattering profiles of wet and dried gels revealed that microporous structures related to the existence of primary particles are present in the gel skeletons at the wet stage and are preserved during drying. Additionally, it is found that the primary particles swollen in the wet condition are dried to compact aggregates to produce the smooth surface of gel skeletons. Upon heating at 400 °C, the particle-particle correlation associated with regularity of mesostructures is enhanced. From nitrogen adsorption-desorption measurements, the average pore size is less than 1 nm in the dried gel and increases to 3.1 nm by the heat treatment. Homogeneous growth of primary particles due to interparticle-polycondensation reaction is responsible for the increased size and uniform distribution of mesopores in the heat-treated gel. © 2008 Springer Science+Business Media, LLC.

DOI： 10.1007/s10971-008-1694-3

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Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

We have successfully prepared multiscale porous crystalline zirconia (ZrO2) monoliths by combining the alkoxy-derived sol-gel process accompanied by phase-separation and the solvothermal process. The gelation can be controlled by the addition of N-methylformamide to the starting solution, while the phase separation is induced by the incorporation of poly(ethylene oxide). Amorphous ZrO2 monolithic gels with well-defined bicontinuous macropores and microstractured skeletons are obtained when the transient structure of polymerization-induced phase separation is fixed by the gelation. The size of the macropores is controlled in the range of 300 nm to 2 μm by adjusting the amount of poly(ethylene oxide). The solvent exchange of the mother liquor in the as-gelled wet specimens with absolute ethanol, followed by the solvothermal treatment at temperatures above 210 °C, brings about the formation of mesopores and stabilizes tetragonal ZrO2 nanocrystals without disturbing the macroporous morphology. The resultant macro-mesoporous crystalline ZrO2 gels possess the surface area over 200 m2 g-1. © 2008 American Chemical Society.

DOI： 10.1021/cm703351d

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J-GLOBAL

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

By combining the micellar templating in nanometer-scale with the polymerization-induced phase separation in micrometer-scale, we can synthesize monolithic silica or silsesquioxane gel materials with hierarchical well-defined macropores and shape-controlled mesopores. Depending on the mechanism of enhancing micellar-templating of siloxane oligomers, macroframeworks containing long-range-ordered cylindrical mesopores with different degrees of order have been produced. Alkylene-bridged silicon alkoxides can also be prepared into similarly hierarchical porous structures with broadened variations in framework morphology. These examples demonstrate the versatility of using phase-separation in micellartemplated gelling systems to obtain well-defined macroporous structures. © 2008 American Chemical Society.

DOI： 10.1021/cm702486b

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J-GLOBAL

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Non-Crystalline Solids  

Cr3+-doped alumina (Al2O3) monoliths with well-defined macropores have been synthesized from the aqueous and ethanolic solution of aluminum and chromium salts in the presence of propylene oxide (PO) and poly(ethylene oxide) (PEO) using the sol-gel method accompanied by phase separation. The addition of PEO to the starting solution induces the phase separation, whereas the introduction of PO controls the gelation. The bicontinuous macroporous structures are obtained by inducing the phase separation parallel to the gelation, and the pore size can be controlled by adjusting the composition of starting solutions. The dried gel and that heat-treated at 700 °C are amorphous. As the heat-treatment temperature is increased over 700 °C, nanocrystalline γ-Al2O3 is precipitated at 800 °C, a mixture of θ- and α-Al2O3 phases appears at 1100 °C, and a single of α-Al2O3 is obtained at 1200 °C, while keeping the bicontinuous macroporous structure. Cr3+-doped α-Al2O3 monoliths with well-defined macropores exhibit photoluminescence as observed for ruby, indicating that Cr3+ ions are homogenously dispersed into the skeletons of bicontinuous network and substitute uniformly for the Al3+ sites. © 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jnoncrysol.2007.06.091

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Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Cr3+-doped alumina (Al2O3) monoliths with well-defined macropores have been synthesized from the aqueous and ethanolic solution of aluminum and chromium salts in the presence of propylene oxide (PO) and poly(ethylene oxide) (PEO) using the sol-gel method accompanied by phase separation. The addition of PEO to the starting solution induces the phase separation, whereas the introduction of PO controls the gelation. The bicontinuous macroporous structures are obtained by inducing the phase separation parallel to the gelation, and the pore size can be controlled by adjusting the composition of starting solutions. The dried gel and that heat-treated at 700 degrees C are amorphous. As the heat-treatment temperature is increased over 700 degrees C, nanocrystalline gamma-Al2O3 is precipitated at 800 degrees C, a mixture of theta- and (alpha-Al2O3 phases appears at 1100 degrees C, and a single of alpha-Al2O3 is obtained at 1200 degrees C, while keeping the bicontinuous macroporous structure. Cr3+-doped alpha-Al2O3 monoliths with well-defined macropores exhibit photoluminescence as observed for ruby, indicating that Cr3+ ions are homogenously dispersed into the skeletons of bicontinuous network and substitute uniformly for the Al3+ sites. (c) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jnonerysol.2007.06.091

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J-GLOBAL

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.11316/jpsgaiyo.63.2.4.0_709_3

掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：MATERIALS RESEARCH SOCIETY  

In various crosslinking systems containing metal oxides, organo-siloxane polymers and pure hydrocarbons, monolithic materials with hierarchical well-defined macropores and controlled mesopores have been synthesized. Synthetic progress in alkoxy-derived macroporous silica lead to the preparation of long-range ordered mesoporous skeletons in well-defined. macroporous framework. Alkylene-bridged silicon alkoxides can also be prepared into similarly hierarchical porous structures with broadened variations in framework morphology. Macro-mesoporous alkoxy-derived pure titania and zirconia have been prepared using hydrochloric acid - mediated processes. Compared with those prepared from colloidal dispersions, alkoxy-derived macroporous titania exhibited much higher mechanical strength. Titania monolith is a promising candidate as a separation medium to discriminate phosphorylated compounds in a liquid chromatography mode. Pure alumina macroporous monolith has been first synthesized from aluminum salt using propylene glycol as a proton scavenger to thrust the solution pH from acidic into neutral conditions. Alumina-based complex oxides such as garnets and spinels can also be prepared in pure phases. Polymerization and phase separation in organic crosslinker system was also controlled to obtain well-defined co-continuous macro-frameworks instead of those composed of aggregated particles. These examples demonstrate the versatility of using phase-separation in gelling systems to obtain well-defined macroporous structures.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：MATERIALS RESEARCH SOCIETY  

By inducing phase separation parallel to the sol-gel transition of alkoxy-derived silica systems, gels having both macroporous and mesoporous structures can be obtained. Using poly(acrylamide) (PAAm) as a phase-separation inducer, macro/mesoporous silica gels were synthesized. After solvent exchange by water, the size distribution of mesopores of wet gels was evaluated by thermoporometry using a differential scanning calorimetry (DSC). Alternatively, gels were evaporation-dried after solvent exchange by ethanol or water/ethanol, followed by heat-treatment to completely remove volatile and organic components. Characterization of the dried or heat-treated samples was carried out using a scanning electron microscope (SEM) and by nitrogen adsorption measurements. Experimental results showed that the interaction between PAAm and silica is not so strong as the case of polymers having poly(oxyethylene) chains. The contribution of the secondary phase separation within the crosslinking silica-rich phase was suggested to be responsible for the mesopore formation in the PAAm-silica system.

Web of Science

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：MATERIALS RESEARCH SOCIETY  

By inducing phase separation parallel to the sol-gel transition of alkoxy-derived silica systems, gels having both macroporous and mesoporous structures can be obtained. Using poly(acrylamide) (PAAm) as a phase-separation inducer, macro/mesoporous silica gels were synthesized. After solvent exchange by water, the size distribution of mesopores of wet gels was evaluated by thermoporometry using a differential scanning calorimetry (DSC). Alternatively, gels were evaporation-dried after solvent exchange by ethanol or water/ethanol, followed by heat-treatment to completely remove volatile and organic components. Characterization of the dried or heat-treated samples was carried out using a scanning electron microscope (SEM) and by nitrogen adsorption measurements. Experimental results showed that the interaction between PAAm and silica is not so strong as the case of polymers having poly(oxyethylene) chains. The contribution of the secondary phase separation within the crosslinking silica-rich phase was suggested to be responsible for the mesopore formation in the PAAm-silica system.

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Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：MATERIALS RESEARCH SOCIETY  

Pure alumina monoliths with well-defined macropores and mesostructured skeleton have been synthesized via a spontaneous route from the aqueous and ethanolic solution of aluminum salts in the presence of propylene oxide and high molecular weight poly(ethylene oxide)(PEO). The addition of propylene oxide to the starting solution controls the gelation, while the addition of PEO induces the phase separation. Appropriate choice of the starting composition, with which the phase separation and gelation concur, produces large-dimension (10mmx10mmx10mm), bicontinuous macroporous Al2O3 monoliths. The mean size of the continuously connected pores is controlled in the micrometer range, depending on the PEO concentration and polarity of the solution. On the other hand, micropores and mesopores, originated from the interstices among primary particles, exhibit median pore size of about 2.6 mn and the BET surface area as high as 396 m(2)/g after dried temperature at 40 degrees C.

Web of Science

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：MATERIALS RESEARCH SOCIETY  

Pure alumina monoliths with well-defined macropores and mesostructured skeleton have been synthesized via a spontaneous route from the aqueous and ethanolic solution of aluminum salts in the presence of propylene oxide and high molecular weight poly(ethylene oxide)(PEO). The addition of propylene oxide to the starting solution controls the gelation, while the addition of PEO induces the phase separation. Appropriate choice of the starting composition, with which the phase separation and gelation concur, produces large-dimension (10mmx10mmx10mm), bicontinuous macroporous Al2O3 monoliths. The mean size of the continuously connected pores is controlled in the micrometer range, depending on the PEO concentration and polarity of the solution. On the other hand, micropores and mesopores, originated from the interstices among primary particles, exhibit median pore size of about 2.6 mn and the BET surface area as high as 396 m(2)/g after dried temperature at 40 degrees C.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Yttrium aluminum garnet, Y3Al5O12, (YAG) monoliths with well-defined macropores have been prepared from ionic precursors using the sol-gel method accompanied by phase separation. The addition of propylene oxide to the starting solution controls the gelation, while the addition of poly(ethylene oxide) induces the phase separation. Polymerization-induced phase separation and gelation concur by an appropriate selection of the starting composition, which allows the production of bicontinuous macroporous nanocomposite gels in large dimensions (similar to 10 x 10 x 10 mm(3)). During heat treatment at 800 degrees C, the monolithic nanocomposite gels crystallize into YAG without the formation of any intermediate phases or the precipitation of impurity phases, indicating higher homogeneity of cation distribution in the dried gels. The macroporous YAG network was maintained even after heat treatment at 1000 degrees C for 10 h.

DOI： 10.2109/jcersj2.115.925

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/pola.22224

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jssc.200700360

PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ar600034p

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PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/cm063051p

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Advanced Materials  

Transparent hydrophobic MSQ aerogels and aerogel-like xerogels have been obtained from a single trifunctional precursor. Two kinds of surfactants were used to suppress phase separation between the hydrophobic MTMS-derived species and polar solvents. Urea acts as a polymerization accelerator to freeze the structure prior to macroscopic phase separation. Some of the obtained gels showed reversible deformation during uniaxial compression tests and thus were successfully dried by evaporation drying under ambient pressures. The obtained xerogels exhibited similar pore properties to corresponding aerogels such as high porosity and transparency. The new method may lead to lower-cost and larger-scale industrial processes, suggesting that aerogels will find increased usage in general applications such as insulators for windows and solar heat panels.

DOI： 10.1002/adma.200602457

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J-GLOBAL

掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.optmat.2005.11.032

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the Ceramic Society of Japan  

Variety of functional porous materials in metal oxide, metalloxane polymer and even pure organic polymer compositions obtained by a sol-gel process are reviewed. Specifically, processes including polymerization-induced phase separation have been extensively introduced from theories to practices. The basic concept of hierarchical pore architecture in monolithic materials is explained, together with several examples of successful applications. Depending on the hierarchy, single, double and triple, unique family of materials can be fabricated. Existing and prospective applications and future challenges of the materials are also shown.

DOI： 10.2109/jcersj.115.169

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Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Biochemical and Biophysical Methods  

Based on the monolithic silica gel materials with hierarchical pore structure and on the SPE devices (MonoTip®) developed thereof, a trypsin-immobilized monolithic silica in a pipette tip (MonoTip® Trypsin) suitable for digesting proteins has been newly developed. The surface of monolithic silica fixed into the tip was chemically modified with trypsin via an aminopropyl group. Trypsin-immobilized monolith successfully performed a rapid digestion of reduced and alkylated proteins with only a few times pipetting operation for the pre-treatment procedure of chromatographic analysis. The novel solid-phase digestion tool using monolithic silica allows a high-throughput trypsin proteolysis of bio-substances in proteomics. © 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jbbm.2006.10.005

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/masy.200750220

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

This article describes the fabrication of multiscale porous nanocrystalline TiO2 monoliths through a one-step method that combines a sol-gel process and phase separation in template-free conditions. A large-dimension monolith with well-defined macropores and a mesostructured anatase-type TiO 2 gel skeleton is spontaneously obtained by controlling the solution pH during the hydrolysis and polycon-densation reactions of titanium alkoxides. The size of the macropores is adjusted by the starting composition, and a crystallized anatase TiO2 skeleton is formed without heat treatment. The use of titanium alkoxide strengthens the gel network by the formation of chemical bonding in the condensation reaction, which yields porous monoliths with higher mechanical strength than for the case of porous monoliths derived from colloidal TiO2 using freeze drying to maintain the porous morphology. The average crystallite size of anatase TiO2 nanocrystals was found to be about 3.6 nm for the dried gel and about 5.0 nm for the gel calcined at 300°C. As a result of the growth of the anatase TiO2 nanoparticles, the mesopores with a median size of 5.0 nm are obtained. The high surface area (∼150 m2/g) is maintained even after the heat treatment at 300°C. © 2006 American Chemical Society.

DOI： 10.1021/cm0617485

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Macroporous crosslinked polymer gels have been prepared via TEMPO-mediated living radical polymerization of divinylbenzene (DVB) in a solvent with a counter polymer. Incorporating a counter polymer, poly(dimethylsiloxane) (PDMS), induced macroscopic spinodal-type phase separation during the course of polymerization of DVB while suppressing the segregation of DVB-derived particles from the solution by living polymerization. Well-defined macroporous morphologies comprising continuous DVB-derived skeletons have thus obtained. Macropore volume and diameter were independently controlled by altering the concentrations of PDMS and the solvent. Since the present polymer gels are prepared using only the multifunctional &quot;crosslinker&quot;, mechanical durability against bending and compression was found to be as high as inorganic ceramics with similar morphologies and porosities. © 2007 Materials Research Society.

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ac060770e

PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jssc.200600335

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PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jssc.200600163

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）  

This work was aimed to development of continuous-flow living radical polymerization in a silica-gel column, &quot;Chromolith&quot;, focusing its separation function by combination of surface chemical absorption and size-exclusion via uniquely shaped mesopores, Thus, living radical copolymerization of two monomers with different polarities, methyl methacrylate (MMA) and 2(dimethylamino)ethyl methacrylate (DMAEMA) was performed with a catalyst [2; Ru(Ind)Cl(PPh3)2] coupled with an initiator (1). Copolymers were continuously produced, and molecular weight distributions were narrower than that in the corresponding batch process.

Scopus

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/adma.200601026

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Science and Technology of Advanced Materials  

Macroporous titania (TiO2) monoliths have been prepared via the sol-gel route started from aqueous anatase-type titania colloid in the presence of poly(ethylene oxide) (PEO), and the light-scattering properties have been investigated by means of coherent backscattering. Well-defined macroporous bicontinuous structures are formed when the transient structure of phase separation is fixed as the permanent morphology by the sol-gel transition. The macroporous morphology, i.e., the size and volume fraction of continuous macropores, can be tailored by adjusting the amount and/or molecular weight of PEO and the TiO2 concentration in the starting solution. During the heat treatment at temperatures above 1000 °C, the skeleton is sintered into fully dense body, and the crystalline structure is transformed from anatase to rutile phases, while keeping the macroporous morphology. We show that the rutile-type TiO2-based macroporous monoliths are strongly scattering media for visible light and that the scattering strength can be controlled by the macroporous morphology. © 2006 NIMS and Elsevier Ltd.

DOI： 10.1016/j.stam.2006.04.014

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J-GLOBAL

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Forensic Toxicology  

A monolithic silica capillary column was first developed in Japan in 2001 as a new tool for better liquid chromatographic separation. The column is made of C18-bonded monolithic silica packed into a capillary glass tube (0.20 mm i.d.). In this study, we used this column for solid-phase extraction of methamphetamine (MA) and amphetamine (AP) in urine. Chromatographic separation was achieved by thin-layer chromatography (TLC) with double-spray detection of each spot. For extraction of amphetamines in urine, samples were mixed with phosphate buffer (pH 3.0, containing 20mM sodium octanesulfate), and the analytes were adsorbed to the column by passing the mixture through it. They were then eluted with a 10-μl volume of ethyl acetate and directly spotted onto a TLC plate. After development, the detection of MA was performed with Simon's reagent. The plate was air-dried, and then over-sprayed with fluorescamine reagent for detection of AP. A fluorescent spot of AP was observed at 365 nm using an ultraviolet viewing system. The detection limits of MA and AP in urine were about 1.0 and 2.0μg/ml, respectively. To confirm the usefulness of this method, the eluent from the column was also analyzed by gas chromatography-mass spectrometry (GC-MS) after derivatization with heptafluorobutyric anhydride. In analysis of 30 actual urine samples, the results obtained by the monolith-TLC system were generally well in accordance with those obtained by GC-MS. © 2006 Japanese Association of Forensic Toxicology and Springer-Verlag Tokyo.

DOI： 10.1007/s11419-006-0009-z

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その他リンク： http://orcid.org/0000-0002-8069-4780

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Separation Science  

Monolithic capillary columns containing native silica gel were covalently modified with 3,5-disubstituted phenylcarbamate derivatives of cellulose and amylose and applied for enantioseparations in capillary LC. The method previously used for covalent immobilization of polysaccharide phenylcarbamate derivatives onto the surface of microparticulate silica gel was successfully adapted for in situ modification of monolithic fused-silica capillary columns. The effects of the nature of polysaccharide and the substituents, as well as of multiple covalent immobilization of polysaccharide derivative on chromatographic performance of capillary columns were studied. The capillary columns obtained using this technique are stable in all solvents commonly used in LC and exhibit promising enantiomer resolving ability. © 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/jssc.200500388

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Non-Crystalline Solids  

Macroporous Al2O3-SiO2 glasses doped with Sm2+ have been prepared from a sol-gel system containing aluminum sec-butoxide, tetramethoxysilane, samarium chloride hexahydrate, poly(ethylene oxide), nitric acid, and water. Monolithic gels having interconnected macropores and skeletons are formed by inducing the phase separation parallel to the gelation. The use of aluminum sec-butoxide preheated at 80 °C as the starting material enables the incorporation of Al3+ into the gel skeleton up to 20 mol% in cation ratio. The maximum amount of Al3+, i.e., 20 mol%, is twice as large as that reported in our previous study, where aluminum sec-butoxide was diluted with sec-butanol prior to the hydrolysis. Heat-treatment of Sm3+-doped 20AlO3/2 · 80SiO2 macroporous glass under the reducing atmosphere converts Sm3+ to Sm2+, which is confirmed by the appearance of intense emission peaks attributed to 4f-4f transitions of Sm2+. © 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jnoncrysol.2006.02.101

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Non-Crystalline Solids  

Sm2+-doped Al2O3-SiO2 glasses with three-dimensionally interconnected macroporous morphology have been prepared via the alkoxide-derived sol-gel process containing poly(ethylene oxide) and SmCl3 · 6H2O. The macroporous morphology is obtained by concurrently inducing the phase separation and sol-gel transition. When the macroporous aluminosilicate glasses doped with Sm2+ are irradiated with a visible light laser at the wavelength of 488 nm, a hole or a dip appears in the plot of fluorescence intensity versus the incident angle of laser beam, indicating that the valence state of Sm2+ is spatially modulated through the interference of multiply scattered light. The hole profile can be controlled by adjusting the macroporous morphology. © 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jnoncrysol.2006.03.024

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J-GLOBAL

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography A  

When bicontinuous gels are prepared via sol-gel method in a 2-dimensionally (2D) confined space, the gel skeletons in the vicinity of interface of a mold are elongated perpendicular to the interface. This phenomenon was attributed to the dynamic wetting of polymerizing siloxane phase onto the interface of the mold under gravity. In this paper, we report the successful preparation of monolithic columns with an oriented pillar structure in a variety of 2D confined spaces. Starting from a solution, which consists of methyltrimethoxysilane (MTMS), the macroporous structure is prepared in situ by a completely spontaneous process. In the oriented pillar structure, bicontinuous siloxane skeletons deformed or disappeared and most pillars are oriented along the direction of gravity. Gel morphologies with the pillar structure were examined by scanning electron microscopy (SEM) and laser scanning confocal microscopy (LSCM). Geometrical information on gel morphologies was numerically derived from the obtained 3D LSCM images. © 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2006.02.059

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography A  

The geometrical properties of co-continuous macroporous silica monoliths have been studied by laser scanning confocal microscopy (LSCM) and a comparison has been made with those obtained by conventional mercury intrusion method. Tetrahedral skeleton model (TMS), which mimics the gel skeleton shape of monoliths, was compared with real monoliths in terms of macropore and porosity using the geometrical parameters extracted from the LSCM observations. Liquid flow behavior through the macroporous silica monoliths was examined in comparison with those simulated using TSM, based on the geometrical properties obtained from LSCM observations. Heterogeneity in macropore topology and connectivity in pores and skeletons are suggested to contribute to the improvement of the model structure for macroporous monoliths. © 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2006.03.087

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J-GLOBAL

掲載種別：研究論文（学術雑誌）  

DOI： 10.1246/bcsj.79.673

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chromatography A  

Monolithic capillary columns containing native silica were modified by in situ coating with amylose tris(3,5-dimethylphenylcarbamate) and applied for enantioseparations in capillary liquid chromatography. Capillary columns were examined for 10 standard racemic compounds in order to compare the performance of monolithic silica columns with the common, 4.6 mm I.D. high-performance liquid chromatographic columns packed with particulate silica. The effects of polysaccharide coating and of the linear velocity of the mobile phase on peak performance were studied. Enantioseparations with an analysis time below 1 min were achieved for some chiral analytes. © 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2006.01.076

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/cm052155h

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Alloys and Compounds  

We have investigated the spatial distribution of Sm2+ inside macroporous alumina-silica (Al2O3-SiO2) glasses having three-dimensionally interconnected skeletons. The Sm 2+-doped Al2O3-SiO2 glasses are prepared via an alkoxy-derived sol-gel route in the presence of poly (ethylene oxide) and SmCl3·6H2O. The well-defined macroporous morphology is obtained by the concurrence of the phase separation and the sol-gel transition. The reduction of Sm3+ to Sm2+ is accomplished by heat treatment under a reducing atmosphere. Two-dimensional images of the fluorescence due to the 4f-4f transition of Sm2+ with the aid of a laser scanning confocal microscope reveal the spatially uniform dispersion of Sm2+ inside the Al2O3-SiO 2 skeleton. © 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2005.01.085

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Polymer Science, Part A: Polymer Chemistry  

An investigation was made of the gelation of dimethacrylate-type crosslinking agents in view of an application for separation media. The study mainly centered on a crosslinking agent, glycerol dimethacrylate (GDMA), which is relatively hydrophilic because of a hydroxyl group in the middle of its structure. The gelation of GDMA was compared with that of other hydrophobic crosslinking agents such as ethylene glycol dimethacrylate and 1,6-hexanediol dimethacrylate. The diluents used in the study were toluene, toluene with methanol, and cyclohexanol. The gelation was observed in real time with a charge coupled device camera and dynamic light scattering (DLS). Also, the separated dry gels were extensively characterized with scanning electron microscopy, BET (N2 absorption and desorption isotherm), and Fourier transform infrared. DLS analysis showed a stronger molecular interaction of GDMA gelation in toluene, whereas this interaction was much weaker in an alcoholic solvent such as toluene with methanol or cyclohexanol. This indicated that GDMA gelation might proceed through hydrogen bonding as well as a crosslinking reaction of vinyl groups. © 2005 Wiley Periodicals, Inc.

DOI： 10.1002/pola.21205

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1295/polymj.PJ2006079

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Funtai Oyobi Fummatsu Yakin/Journal of the Japan Society of Powder and Powder Metallurgy  

The tuning of light scattering strength has been demonstrated for organic-inorganic hybrid monoliths with well-defined through-pores in micrometer range. Macroporous gels having interconnected pores and skeletons are obtained in a system containing methyltrimethoxysilane, water, nitric acid, and methanol using an alkoxy-derived sol-gel method combined with the phase separation. The sizes of pores and skeletons can be controlled by varying molar ratios of water and methanol in the starting compositions which mostly affect the onset of polymerization-induced phase separation in the system. The mercury porosimetry shows that the resultant gels have a sharp pore size distribution, and the average pore diameter increases with increasing the amount of water and methanol. The coherent backscattering measured for the gels formed in between two slide glasses reveals that the transport mean free path of light decreases with decreasing the sizes of pores and skeletons. Pore size dependence of the scattering strength can be qualitatively explained by a Mie scattering calculation using a model in which spherical pores are randomly distributed in methylsiloxane matrix. The results indicate that the scattering strength can be tuned by controlling the sizes of the pores.

DOI： 10.2497/jjspm.52.781

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecular Materials and Engineering  

Uniformly sized polymer particles were prepared by an emulsification and polymerization technique utilizing a silica monolithic membrane, namely the "silica monolithic membrane emulsification technique". In this paper, we utilized silica monolithic membrane as a device for the preparation of uniformly sized polymer particles. A mixture of monomers, diluents and oil-soluble initiator was emulsified into a continuous medium through the silica monolithic membrane and polymerized. The particles obtained had a higher size uniformity than that of particles prepared by previously reported membrane emulsification techniques, such as the Shirasu Porous Glass (SPG) emulsification technique. Through the silica monolithic membrane emulsification technique, we could prepare particles having availability as a possible packing material for solid-phase extraction (SPE) and high performance liquid chromatography (HPLC). © 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/mame.200500006

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Analytical Chemistry  

This paper describes the use of computational fluid dynamics for the calculation of the flow resistance through computer-generated models resembling silica monoliths. This study was undertaken to determine the effect of skeleton heterogeneity on the flow resistance and, more precisely, to test the hypothesis that increased skeleton heterogeneity decreases the flow resistance. To evaluate the proposed model, 24 real silica monoliths have been prepared using the same method, covering a wide range of skeleton sizes (2.2 μm < d s < 8 μm) and porosities (0.47 < ε < 0.66). The permeability of these monoliths was determined by pressure drop measurements, and structural information was obtained by image analysis of laser scanning confocal microscopy-generated 3D images of the skeleton structure. The results indicate that the presence of preferential flow paths due to an increased heterogeneity of the flow through pore space reduces the flow resistance of monolithic media. It is also shown that the pore size is hence a much better suited scaling dimension than the skeleton size to reduce the permeability of monolithic columns. © 2005 American Chemical Society.

DOI： 10.1021/ac0502798

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.chroma.2004.09.042

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry of Materials  

Monolithic pure silica gels with hierarchical macro-mesoporous structure have been synthesized via a spontaneous sol-gel process from silicon alkoxide using a structure-directing agent and a micelle-swelling agent. A monolithic body with well-defined co-continuous macropores is a result of concurrent phase separation and sol-gel transition induced by the polymerization reaction, whereas the mesopores are templated by the cooperative self-assembly of inorganic species, a structure-directing agent, and a micelle-swelling agent. These bimodal pore systems are formed spontaneously in a closed condition at a constant temperature. The following removal of surfactants by heat-treatment gives silica gels with hierarchical and fully accessible pores in discrete size ranges of micrometers and nanometers. The highly ordered 2D-hexagonal arrays of mesopores have been confirmed by X-ray diffraction measurements and FE-SEM observations. Furthermore, by further additions of the micelle-swelling agent, the mesostructural transition from well-ordered 2D-hexagonal arrays to mesostructured cellular foams (MCF) has been induced accompanied by minor modifications of the micrometer-range structure. © 2005 American Chemical Society.

DOI： 10.1021/cm048091c

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s11095-005-2485-y

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掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Sol-Gel Science and Technology  

Structural rearrangement of sol-gel-derived silica gel by aging under basic conditions was investigated using small angle X-ray scattering (SAXS) and 29Si nuclear magnetic resonance (NMR). A wet silica gel prepared under acidic conditions had a fractal nature and many unreacted silanols remained on the surface. During aging of the gel in ammonia solution additional Si-O-Si bonds rapidly formed whereas the change in mesoscale structure gradually proceeded. This result was compared with that of simulation modeling the Ostwald ripening i.e. dissolution from positive curvature and reprecipitation on negative curvature. In the simulation structural change in a cluster from fractal nature to particle aggregates was well visualized in 2-dimmensional square lattice. Both scattering profiles calculated from the model clusters and the change in average coordination number of monomers in the cluster well agreed with the experimental SAXS and NMR results respectively. This agreement strongly ensures us that structural change by aging under basic conditions proceeds through the Ostwald ripening. The mesopore size as well as mesopore volume in calcined silica gel is determined by the shrinkage degree during drying and calcination. The sample aged in basic solution restrains the shrinkage because of the growth of particulate structure and retains large size and volume of pores. © 2005 Springer Science + Business Media, Inc.

DOI： 10.1007/s10971-005-5610-9

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jssc.200401932

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Progress in Biomedical Optics and Imaging - Proceedings of SPIE  

Sm2+-doped Al2O3-SiO2 glasses with three-dimensionally interconnected macroporous morphology have been prepared via the alkoxy-derived sol-gel process containing poly (ethylene oxide) and SmCl3·6H2O. The macroporous morphology is obtained by concurrently inducing the phase separation and sol-gel transition. Using a visible laser with the wavelength of 488 nm, the valence state of Sm2+ has been manipulated spatially. When the photoionization of Sm2+ is combined with multiple light scattering in the porous glasses, holes are burned in wave-vector domain. The hole profile can be controlled by adjusting the macroporous morphology.

DOI： 10.1117/12.590712

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1159/000081684

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Progress in Biomedical Optics and Imaging - Proceedings of SPIE  

Macroporous titania (TiO2) monoliths have been prepared by the sol-gel method including phase separation, and the light-scattering properties have been investigated by means of coherent backscattering. Macroporous TiO 2 gels are obtained in the systems containing aqueous titania colloid and poly(ethylene oxide) (PEO). Three-dimensionally interconnected macroporous structure is formed when the transient structure of phase separation is fixed as the permanent morphology by the sol-gel transition. The domain size of macroporous TiO2 gels can be controlled reproducibly by adjusting the concentration of PEO. During the heat treatment above 1000°C, the TiO 2 skeleton is sintered into fully dense body and the crystalline structure is transformed from anatase to rutile, while maintaining macroporous morphology. We show that the rutile-type TiO2 -based macroporous monoliths are strongly scattering media for visible light.

DOI： 10.1117/12.591059

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Materials Chemistry  

Siloxane-based organic-inorganic hybrid monoliths with well-defined macropores and/or mesopores have been synthesized by a sol-gel process, accompanied by polymerization-induced phase separation. Using aklyltrialkoxysilanes and alkylene-bridged alkoxysilanes, two different categories of organosiloxane networks have been characterized in view of macroporosity (based on phase separation) and mesoporosity (supramolecularly templated by surfactants). While the alkyl-terminated poly(siloxane) networks exhibit substantial surface hydrophobicity accompanied by mechanical flexibility, the alkylene-bridged networks behave much more similarly to those prepared from tetraalkoxysilanes with regard to surface hydrophilicity, mechanical rigidness and mesopore-forming ability. The supramolecular templating of mesopores embedded in the gel skeletons (which comprise well-defined macroporous networks) has proven to give a wide variety of hierarchically- designed macro-mesoporous hybrid materials. © The Royal Society of Chemistry 2005.

DOI： 10.1039/b508415f

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.1823596

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/jp0481658

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jnoncrysol.2004.08.059

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/cm049320y

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1246/cl.2004.1120

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1143/JJAP.43.5359

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.chroma.2004.03.025

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jssc.200401819

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jssc.200401842