受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞国：日本国

受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞国：日本国

受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：日本国

担当区分：最終著者,　責任著者   記述言語：日本語   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）   出版者・発行元：RSC Advances  

ZnO nano-bullets were synthesized using solution plasma from only Zn electrode in water without any chemical agents. In this sustainable synthesis system, the rapid quenching reaction at the interface between the plasma/liquid phases facilitates the fast formation of nano-sized materials. The coil-to-pin type electrode geometry, which overcomes the discharge interruption owing to the electrode gap broadening of the typical pin-to-pin type enables the synthesis of numerous nanomaterials through a stable discharge for 1 h. The as-prepared samples exhibited a high crystalline ZnO structure without post calcination, and the length and width were 71.8 and 29.1 nm, respectively. The main exposed facet of ZnO nano-bullets was the (100) crystal facet, but interestingly, the (101) facet was confirmed at the inclined surfaces in the edges. The (101) crystal facet has an asymmetric Zn and O atom arrangement, and it could result in a focused electron density area with relatively high reactivity. Therefore, ZnO nano-bullets are promising materials for applications in advanced technologies.

DOI： 10.1039/d1ra05008g

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：ACS Applied Materials and Interfaces  

The emergent solar-driven water evaporation technology provides a reassuring scheme for red mud (RM) utilization in environment and materials science. With fewer restrictions on raw materials, wide availability of sheer quantity, and high complexity in chemical composition, the RM may be a promising candidate for solar absorbers. Here, we developed a novel solar absorber with reduced RM. It features favorable light absorption and photothermal conversion ability using biomass pyrolysis. When added to the polyvinyl alcohol and chitosan gel substrate, the light absorptance can reach 94.65%, while the corresponding evaporation rate is as high as 2.185 kg m-2 h-1 under an illumination density of 1 kW m-2. We further demonstrated its potential as an efficient solar absorber in the solar-driven water evaporation and the thermoelectric device to realize the stable and efficient coproduction of vapor and electricity.

DOI： 10.1021/acsami.1c05228

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：Japanese Journal of Applied Physics  

This research paper reports the enhanced hole-transporting ability of widely utilized poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) achieved by applying cationic nitrogen-doped graphene (CNG) as a p-type modifier for efficient organic solar cells (OSCs). The power conversion efficiency (PCE) of the CNG-coated PEDOT:PSS-applied OSC reaches 2.76%, which is an increase of 40% compared to that of the pristine PEDOT:PSS-applied OSC (1.96%). The significantly enhanced performance is contributed by the increased hole-transporting ability, and the improved interfacial morphology of PEDOT:PSS, which affords high-quality active layers.

DOI： 10.35848/1347-4065/ac00fc

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：ACS Applied Energy Materials  

Carbon materials are widely utilized to support platinum (Pt) catalysts for proton exchange membrane fuel cells (PEMFCs). However, carbon surfaces generally promote hydrophobicity, which limits the transport of active species and lowers the efficiency of PEMFCs. Consequently, functional groups should be introduced on the carbon surface to create transport channels. One promising strategy is to modify the amphiphilic functional group on a carbon surface. In this study, the liquid-phase plasma process was applied to realizing a facile one-step synthesis of amphiphilic functional group-modified carbon-supported platinum (Am@C/Pt) to serve as a catalyst. This novel synthesis strategy provides several advantages over conventional processes, such as reducing the number of steps and minimizing the chemical and energy consumptions. Experimental results revealed that the PEMFCs' efficiency with Am@C/Pt is mainly controlled by the number of hydrophilic and hydrophobic characters on the carbon surface. A single PEMFC demonstrated a maximum current and power density of 2.41 A cm-2 and 1.68 W cm-2, respectively, at 0.7 V, which was significantly higher than those of commercially available carbon-supported Pt catalysts. Furthermore, Am@C/Pt demonstrated superior durability after 5000 test cycles.

DOI： 10.1021/acsaem.1c00406

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：International Journal of Molecular Sciences  

Sustainability and environmental concerns have persuaded researchers to explore renewable materials, such as nature-derived polysaccharides, and add value by changing chemical structures with the aim to possess specific properties, like biological properties. Meanwhile, finding methods and strategies that can lower hazardous chemicals, simplify production steps, reduce time consumption, and acquire high-purified products is an important task that requires attention. To break through these issues, electrical discharging in aqueous solutions at atmospheric pressure and room temperature, referred to as the “solution plasma process”, has been introduced as a novel process for modification of nature-derived polysaccharides like chitin and chitosan. This review reveals insight into the electrical discharge in aqueous solutions and scientific progress on their application in a modification of chitin and chitosan, including degradation and deacetylation. The influencing parameters in the plasma process are intensively explained in order to provide a guideline for the modification of not only chitin and chitosan but also other nature-derived polysaccharides, aiming to address economic aspects and environmental concerns.

DOI： 10.3390/ijms22094308

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：Materials Advances  

Nanocarbons were successfully synthesized from benzene (BZ), nitro-benzene (BZ-NO2) and aniline (BZ-NH2) by solution plasma process (SPP). The SPP was generated by a bipolar pulsed power supply between two tungsten electrodes at room temperature. The synthesized nanocarbons were investigated. The highest synthesis rate, 40 mg min-1, was for the BZ nanocarbon. The transmission electron microscopy (TEM) morphology showed that the nanocarbon sizes were 15-25 nm. The Brunauer-Emmett-Teller (BET) analysis shows a highest surface area of 220 m2 g-1, pore size of 0.45 cm3 g-1, and average pore diameter of 20.0 nm for the BZ nanocarbon. Cyclic voltammetry (CV) in an acidic medium exhibited the oxygen reduction reaction (ORR) of the nanocarbons. The nanocarbon from BZ-NH2 obtained a high special capacity of 15 500 mA h per g of carbon at the discharge rate of 0.1 mA cm-2 with 1.0 mg carbon loading for the lithium (Li)-air battery. The ORR is an important reaction in Li-air batteries and fuel cells for the application of next-generation batteries and energy conversion devices.

DOI： 10.1039/d0ma00926a

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：Polymers  

Multicomponent nanoparticles containing carbon, tungsten carbide and silver (carbon-WC-Ag nanoparticles) were simply synthesized via in-liquid electrical discharge plasma, the so-called solution plasma process, by using tungsten electrodes immersed in palm oil containing droplets of AgNO3 solution as carbon and silver precursors, respectively. The atomic ratio of carbon:W:Ag in carbon-WC-Ag nanoparticles was 20:1:3. FE-SEM images revealed that the synthesized carbon-WC-Ag nanoparticles with particle sizes in the range of 20–400 nm had a spherical shape with a bumpy surface. TEM images of carbon-WC-Ag nanoparticles showed that tungsten carbide nanoparticles (WCNPs) and silver nanoparticles (AgNPs) with average particle sizes of 3.46 nm and 72.74 nm, respectively, were dispersed in amorphous carbon. The carbon-WC-Ag nanoparticles were used as multifunctional fillers for the preparation of polylactic acid (PLA) composite films, i.e., PLA/carbon-WC-Ag, by solution casting. Interestingly, the coexistence of WCNPs and AgNPs in carbon-WC-Ag nanoparticles provided a benefit for the co-nucleation ability of WCNPs and AgNPs, resulting in enhanced crystallization of PLA, as evidenced by the reduction in the cold crystallization temperature of PLA. At the low content of 1.23 wt% carbon-WC-Ag nanoparticles, the Young’s modulus and tensile strength of PLA/carbon-WC-Ag composite films were increased to 25.12% and 46.08%, respectively. Moreover, the PLA/carbon-WC-Ag composite films possessed antibacterial activities.

DOI： 10.3390/polym13070991

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：IEEE Robotics and Automation Letters  

Selection of appropriate tools and use of them when performing daily tasks is a critical function for introducing robots for domestic applications. In previous studies, however, adaptability to target objects was limited, making it difficult to accordingly change tools and adjust actions. To manipulate various objects with tools, robots must both understand tool functions and recognize object characteristics to discern a tool-object-action relation. We focus on active perception using multimodal sensorimotor data while a robot interacts with objects, and allow the robot to recognize their extrinsic and intrinsic characteristics. We construct a deep neural networks (DNN) model that learns to recognize object characteristics, acquires tool-object-action relations, and generates motions for tool selection and handling. As an example tool-use situation, the robot performs an ingredients transfer task, using a turner or ladle to transfer an ingredient from a pot to a bowl. The results confirm that the robot recognizes object characteristics and servings even when the target ingredients are unknown. We also examine the contributions of images, force, and tactile data and show that learning a variety of multimodal information results in rich perception for tool use.

DOI： 10.1109/LRA.2021.3062004

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：Materials Advances  

N-Doped few-layer graphene encapsulated Pt-based bimetallic nanoparticles were successfully synthesized via the solution plasma (SP) method. This synthesis strategy can be achieved in one pot by using only pure dimethylformamide (DMF) as the reaction solution at room temperature and atmospheric pressure. The structural analyses exhibited a fine core-shell structured nanoparticle (2-4 nm), which had Pt and Pt-based bimetallic nanoparticles as a core and N-doped few-layer graphene (NFG), having 2-4 layers, as a shell. Pt-based bimetallic cores (i.e., PtAu, PtAg, and PtPd) were varied depending on the metal electrodes used in the SP process. The electrocatalytic activity toward the oxygen reduction reaction (ORR) of the obtained samples in an acidic solution was found to be acceptable, while possessing excellent durability, compared to those of the commercial carbon-supported Pt catalyst. The effective ORR activity was possibly attributed to the synergistic effect of the Pt-based bimetallic core and N-doped graphene shell which contained high amounts of pyridinic-N and quaternary-N. The results in a single fuel cell test expressed the superiority of our SP-derived sample in the fuel cell performances to commercial Pt/C. This study not only proposed potential alternative ORR catalysts with acceptable electrocatalytic activity and high durability but also provided guidelines for the facile synthesis of carbon-based core-shell nanostructured materials with low chemical use via the SP process. This journal is

DOI： 10.1039/d0ma00718h

Web of Science

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：ACS Applied Materials and Interfaces  

Volume expansion hinders conversion-type transition-metal oxides (TMOs) as potential anode candidates for high-capacity lithium-ion batteries. While nanostructuring and nanosizing have been employed to improve the cycling stability of TMOs, we show here that both high initial Coulombic efficiency (ICE) and stable cycling reversibility are achieved in the layered compound Li0.9Nb0.9Mo1.1O6 (L0.9NMO) by inherent properties of the bulk crystal structure. In this model, MoO6 octahedra as active centers react with lithium ions and endow capacity, while a grid composed of NbO6 octahedra effectively suppresses the volume expansion, enhances the conductivity, and supports the structural skeleton from collapse. As a result, bulk L0.9NMO not only delivers a high discharge capacity of 1128 mA h g-1 at 100 mA g-1 with a considerable ICE of 87% but also exhibits long cycling stability and good rate performance (339 mA h g-1 after 500 cycles at 1 A g-1 with an average Coulombic efficiency approaching 100%). The self-confined structure provides a competitive strategy for stable conversion-type lithium storage.

DOI： 10.1021/acsami.1c02269

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：Nano Research  

Solid lithium-sulfur batteries (SLSBs) show potential for practical application due to their possibility for high energy density. However, SLSBs still face tough challenges such as the large interface impedance and lithium dendrite formation. Herein, a high-performance SLSB is demonstrated by using a fiber network reinforced Li6.75La3Zr1.75Ta0.25O12 (LLZTO) based composite solid electrolyte (CSE) in combination with sulfurized polyacrylonitrile (SPAN) cathode. The CSE consisting of an electrospun polyimide (PI) film, LLZTO ionically conducting filler and polyacrylonitrile (PAN) matrix, which is named as PI-PAN/LLZTO CSE, possesses high room-temperature ionic conductivity (2.75 × 10−4 S/cm), high Li+ migration number (tLi+) of 0.67 and good interfacial wettability. SPAN is utilized due to its unique electrochemical properties: reasonable electronic conductivity and no polysulfides shuttle effect. The CSE enables a highly stable Li plating/stripping cycle for over 600 h and good rate performance. Moreover, the assembled SLSB exhibits good cycle performance of accomplishing 120 cycles at 0.2 C with the capacity retention of 474 mAh/g, good rate properties and excellent long-term cycling stability with a high capacity retention of 86.49% from 15th to 1,000th cycles at 1.0 C. This work rationalizes our design concept and may guide the future development of SLSBs. [Figure not available: see fulltext.].

DOI： 10.1007/s12274-021-3981-z

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：Progress of Theoretical and Experimental Physics  

The emission of muonium (μ+e-) atoms into vacuum from silica aerogel with laser ablation on its surface was studied with various ablation structures at room temperature using the subsurface muon beams at TRIUMF and Japan Proton Accelerator Research Complex (J-PARC). Laser ablation was applied to produce holes or grooves with typical dimensions of a few hundred μm to a few mm, except for some extreme conditions. The measured emission rate tends to be higher for larger fractions of ablation opening and for shallower depths. More than a few ablation structures reach the emission rates similar to the highest achieved in past measurements. The emission rate is found to be stable at least for a couple of days. Measurements of spin precession amplitudes for the produced muonium atoms and remaining muons in a magnetic field determine a muonium formation fraction of (65.5 pm 1.8)%. The precession of the polarized muonium atoms is also observed clearly in vacuum. A projection of the emission rates measured at TRIUMF to the corresponding rates at J-PARC is demonstrated taking the different beam condition into account reasonably.

DOI： 10.1093/ptep/ptaa145

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：Energy Storage Materials  

Solid polymer electrolytes (SPEs) garner tremendous attention for both enabling higher energy density battery chemistry and alleviating the safety concerns of liquid electrolytes, but the practical utilizations of SPEs are severely hindered by the limited room temperature ionic conductivity, low transference number and huge interface impedance. Unlike the polymer chain movement in traditional SPEs, in the present work, we develop novel “polymer-in-plastic salts” electrolytes (PIPSEs) via a high weight ratio of plastic salts to polymer in which polymer just function as framework so that non-flammable, superionic conductive and flexible SPEs can be obtained. Also, the high content of plastic salts in PIPSEs can wet electrodes and form compatible solid electrolyte interface (SEI) with lithium metal. As a consequence, solid-state dendrite-free symmetric Li cells with PIPSEs show ultralong cycle life over 1000 h under up to 2.0 mA cm−2 and Li/LiFePO4 and high-voltage Li/LiNi0.6Co0.2Mn0.2O2 cells utilizing above PIPSEs exhibit excellent cycle performance and appealing rate performance. It is anticipated that our work provides a new strategy for the next-generation solid-state batteries.

DOI： 10.1016/j.ensm.2020.09.003

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：IEEE International Conference on Intelligent Robots and Systems  

We propose a deep learning model for a robot to wipe 3D-objects. Wiping of 3D-objects requires recognizing the shapes of objects and planning the motor angle adjustments for tracing the objects. Unlike previous research, our learning model does not require pre-designed computational models of target objects. The robot is able to wipe the objects to be placed by using image, force, and arm joint information. We evaluate the generalization ability of the model by confirming that the robot handles untrained cube and bowl shaped-objects. We also find that it is necessary to use both image and force information to recognize the shape of and wipe 3D objects consistently by comparing changes in the input sensor data to the model. To our knowledge, this is the first work enabling a robot to use learning sensorimotor information alone to trace various unknown 3D-shape.

DOI： 10.1109/IROS45743.2020.9341275

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：ACS Applied Nano Materials  

The exploration of novel carbon material systems has emerged as a promising strategy for yielding unique and unconventional functional properties. In this study, a cationic nitrogen-doped carbonwrapped single-walled carbon nanotube (CN-C@SWCNT) was synthesized for the first time via solution plasma (SP) by using an aniline aqueous solution with the SWCNT dispersion under ambient conditions. The reactive species produced from SP led to the formation of cationic nitrogendoped carbon (CN-C) completely wrapped around SWCNT. Raman spectroscopy, electron diffraction, and X-ray photoelectron spectroscopy confirmed the presence of cationic nitrogen. CN-C@SWCNT exhibited an excellent electrical conductivity of 120.30 S cm-1. Room-temperature halleffect measurements revealed p-type semiconducting behavior for CN-C@ SWCNT, with a carrier concentration of 4.6 × 1020 cm-3. The electrical conductivity and carrier concentration of p-type CN-C@SWCNT were greater than those reported previously for carbon-based materials. The high electrical properties of CN-C@SWCNT were synergistically related to a conducting bridge between CN-C and SWCNT conducting domains and the presence of doped cationic nitrogen. The SP-synthesized CN-C@SWCNT demonstrates immense potential as an emerging class of p-type carbon materials in advanced electrocatalytic applications.

DOI： 10.1021/acsanm.0c02164

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：RSC Advances  

Metal-carbon core-shell nanostructures have gained research interest due to their better performances in not only stability but also other properties, such as catalytic, optical, and electrical properties. However, they are limited by complicated synthesis approaches. Therefore, the development of a simple method for the synthesis of metal-carbon core-shell nanostructures is of great significance. In this work, a novel Cu-core encapsulated by a N-doped few-layer graphene shell was successfully synthesized in a one-pot in-liquid plasma discharge, so-called solution plasma (SP), to our knowledge for the first time. The synthesis was conducted at room temperature and atmospheric pressure by using a pair of copper electrodes submerged in a DMF solution as the precursor. The core-shell structure of the obtained products was confirmed by HR-TEM, while further insight information was explained from the results of XRD, Raman, and XPS measurements. The obtained Cu-core encapsulated by the N-doped few-layer graphene shell demonstrated relatively high stability in acid media, compared to the commercial bare Cu particles. Moreover, the stability was found to depend on the thickness of the N-doped few-layer graphene shell which can be tuned by adjusting the SP operating conditions. This journal is

DOI： 10.1039/d0ra07162e

Scopus

担当区分：最終著者   掲載種別：研究論文（学術雑誌）   出版者・発行元：Carbohydrate Polymers  

DOI： 10.1016/j.carbpol.2020.116162

Scopus

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）   出版者・発行元：Organic Chemistry Frontiers  

An addition reaction of pyridine-tetrafluoro-λ6-sulfanylchlorides (Py-SF4Cl) to alkynes and alkenes providing pyridine-tetrafluoro-λ6-sulfanyl-alkenes and pyridine-tetrafluoro-λ6-sulfanyl-alkanes is represented. The addition of Py-SF4Cl occurs spontaneously in the presence of reactants, even in total darkness, but is affected in the presence of light. A series of SF4-bridged pyridines were efficiently synthesized under a couple of environmentally benign conditions in good to high yields. The spontaneous reaction of Py-SF4Cl is discussed based on the time-dependent analyses of the reaction in the presence or absence of photo-irradiation, and could proceed via a radical process.

DOI： 10.1039/d0qo00339e

Scopus

担当区分：最終著者   掲載種別：研究論文（学術雑誌）   出版者・発行元：Cellulose  

DOI： 10.1007/s10570-019-02866-3

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：ACS Applied Nano Materials  

Amino-modified nanocarbon (NH2-C) has been widely used as an adsorbent for transition metal ion adsorption due to its high specific surface area, high electrical charge, and the ability to form a coordinate linkage to a transition metal ion. In this work, NH2-C was successfully synthesized from a mixture of phenol and (3-aminopropyl)triethoxysilane (APTES) through solution plasma processing, which performs both carbonization and amination simultaneously. This synthesis method eliminates the need to functionalize carbon with amino groups, as is required in the conventional process. Our NH2-C shows a better dispersion and a higher number of amino groups on both the external surface and inner pores, which enhances the adsorption capacity. The maximum capacities for Cu2+, Zn2+, and Cd2+ adsorption were 144.9, 115.4, and 102.0 mg g-1, respectively. These values were higher than those of five typical NH2-Cs synthesized by a conventional process. Based on the adsorption mechanism derived from adsorption kinetic, isotherm, and thermodynamic studies, the transition metal ions were chemisorbed to the surface in a monolayer endothermically and spontaneously. Moreover, it was found that NH2-C was suitable for use in ten consecutive adsorption-desorption cycles without significant loss of adsorption capacity.

DOI： 10.1021/acsanm.9b01915

Scopus

担当区分：最終著者   掲載種別：研究論文（学術雑誌）   出版者・発行元：Carbohydrate Polymers  

DOI： 10.1016/j.carbpol.2019.115377

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：Proceedings of the 29th Linear Accelerator Conference, LINAC 2018  

The muon linac is planned at the Japan Proton Accelerator Research Complex (J-PARC) for the precision measurement of the muon dipole moments. However, the muon acceleration with an radio-frequency (RF) accelerator was not carried out yet. Then, the first muon RF acceleration experiment using an radio-frequency quadrupole (RFQ) linac was carried out in the J-PARC. The incident positive muon was cooled using the production of the negative muonium ion (Mu-) before the accelaration. Subsequently, the Mu- was accelerated to 89 keV with the RFQ. Thanks to the pulsed muon beam in the J-PARC, the accelerated Mu- was clearly identified with the Time-Of-Flight measurement after the momentum selection with the bending magnet. The measured event rate of the accelerated Mu- was consistent with the expectation using the simulation and the result of the Mu- production experiment as the preparatory experiment of the acceleration experiment. The first muon RF acceleration was successful.

DOI： 10.18429/JACoW-LINAC2018-TUPO010

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：Proceedings of the 29th Linear Accelerator Conference, LINAC 2018  

An inter-digital H-mode (IH) drift-tube linac (DTL) is developed for a low velocity part in a muon linac at the J-PARC E34 experiment. It will accelerate muons from ß = 0.08 to 0.28 at an operational frequency of 324 MHz. In order to achieve higher acceleration efficiency and make cost lower, an alternative phase focusing (APF) scheme is adopted. A prototype with 6 cells of 0.45 m length was manufactured. The prototype accelerates muons from ß = 0.08 to 0.15 stage. We conducted frequency measurement and bead-pull measurement as a low-power measurement, in order to evaluate the prototype product. In this paper, the results of the low-power measurement for prototype cavity will be presented.

DOI： 10.18429/JACoW-LINAC2018-MOPO085

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：ACS Applied Nano Materials  

Wrapping of gold nanoparticles (AuNPs) with a biocompatible matrix, to gain AuNP colloids, is a general strategy to synthesize the AuNPs for biomedical purposes. This work reports the synthesis of AuNP colloids in the aqueous solution of several natural matrices using a liquid-phase plasma process. Two classes of natural substances used are sugars (including: glucose, fructose, and sucrose) and biopolymers (including: carboxymethyl cellulose, sodium alginate, and gelatin). All are negatively charged water-soluble substances that are claimed to be sources of energy for cells to grow and have a high potential to be compatible with them. The study has emerged since one question arises: "Do these matrices also promote the growth of cancer cells?" The synthesis is performed by generating plasma across a pair of electrodes immersed in an aqueous solution of a natural matrix containing a gold precursor (HAuCl4·3H2O). Two concentrations of the matrices (0.5 and 1.0% w/v) are used, and the plasma treatment times are varied (0, 10, and 30 min). The effect of the type and concentration of natural matrices as well as the plasma treatment time on the formation of AuNPs, along with their physical and chemical properties, including morphology, size, hydrodynamic diameter (dh), colloidal stability, and charge on the AuNP surface, is evaluated. We find that the charge of the AuNP surfaces could be altered by the plasma treatment. Eventually, cytotoxicity test results against normal (MRC-5) and cancer (H460 and HeLa) cell lines could not only answer our opening question but also suggest a rather complex response. Our findings indicate the great potential of the obtained AuNP colloids as a part of cancer therapy.

DOI： 10.1021/acsanm.9b02106

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：Journal of Physics: Conference Series  

Negative muonium atom (μ + e - e -, Mu-) has unique features stimulating potential interesting for several scientific fields. Since its discovery in late 1980's in vacuum, it has been discussed that the production efficiency would be improved using a low-work function material. C12A7 was a well-known insulator as a constituent of alumina cement, but was recently confirmed to exhibit electric conductivity by electron doping. The C12A7 electride has relatively low-work function (2.9 eV). In this paper, the negative muonium production measurement with several materials including a C12A7 electride film will be presented.

DOI： 10.1088/1742-6596/1350/1/012067

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：Nanomaterials  

The synthesis of carbon nanoparticles (Cn) and oxygen-doped nanocarbon (OCn) was successfully done through a one-step synthesis by the solution plasma process (SPP). The Cn and OCn were nitrogen-doped by nitridation under an ammonia atmosphere at 800◦C for 2 h to yield NCn and NOCn, respectively, for carbon dioxide (CO2) adsorption. The NOCn exhibited the highest specific surface area (~570 m2 g−1) and highest CO2 adsorption capacity (1.63 mmol g−1 at 25◦C) among the synthesized samples. The primary nitrogen species on the surface of NOCn were pyridinic-N and pyrrolic-N. The synergistic effect of microporosity and nitrogen functionality on the NOCn surface played an essential role in CO2 adsorption enhancement. From the thermodynamic viewpoint, the CO2 adsorption on NOCn was physisorption, exothermic, and spontaneous. The NOCn showed a more negative enthalpy of adsorption, indicating its stronger interaction for CO2 on the surface, and hence, the higher adsorption capacity. The CO2 adsorption on NOCn over the whole pressure range at 25–55◦C best fitted the Toth model, suggesting monolayer adsorption on the heterogeneous surface. In addition, NOCn expressed a higher selective CO2 adsorption than Cn and so was a good candidate for multicycle adsorption.

DOI： 10.3390/nano9121776

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：IEEE International Conference on Robotics and Biomimetics, ROBIO 2019  

We propose a sensorimotor dynamical system model for pouring unknown liquids. With our system, a robot holds and shakes a bottle to estimate the characteristics of the contained liquid, such as viscosity and fill level, without calculating to determine their parameters. Next, the robot pours a specified amount of the liquid into another container. The system needs to integrate information on the robot's actions, the liquids, the container, and the surrounding environment to perform the estimation and execute a continuous pouring motion using the same model. We use deep neural networks (DNN) to construct the system. The DNN model repeats prediction and execution of the actions to be taken in the next time step based on the input sensorimotor data, including camera images, force sensor data, and joint angles. At the same time, the DNN model acquires liquid characteristics in the internal state. We confirmed that the DNN model can control the robot to pour a desired amount of liquid with unknown viscosity and fill level.

DOI： 10.1109/ROBIO49542.2019.8961718

Scopus

担当区分：最終著者,　責任著者   掲載種別：研究論文（学術雑誌）   出版者・発行元：Plasma Processes and Polymers  

DOI： 10.1002/ppap.201900012

Web of Science

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：Organic Chemistry Frontiers  

We present a catalyst-free method for the synthesis of aryl and heteroaryl tetrafluoro-λ6-sulfanyl chlorides (Ar-SF4Cl) by using trichloroisocyanuric acid and potassium fluoride in acetonitrile. The method has wide substrate generality and proceeded well with high yields even in the absence of acid catalysts. The preparation of meta- and para-SF4Cl-substituted pyridines using TCCA was achieved for the first time.

DOI： 10.1039/c9qo00191c

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：ACS Applied Nano Materials  

Tailoring electrical properties of graphene by nitrogen doping is currently of great significance in a broad area of advanced applications. Bonding configuration of nitrogen atoms in graphene plays a vital role in controlling its electrical, chemical, and optical properties. Here, we report for the first time a simple bottom-up synthesis of a novel cationic nitrogen-doped graphene (CNG) by a solution plasma (SP). A mixture of ionic liquid and organic solvent was used as starting precursor. CNG exhibited an orthorhombic structure possibly due to the presence cationic nitrogen in hexagonal graphene lattice. Nitrogen doping content was found to be as high as 13.4 atom %. Electrical characterization demonstrated that the CNG exhibited a p-type semiconducting behavior with superior electrical conductivity and carrier concentration. Such unique electrical characteristics of CNG are mainly attributed to the presence of cationic nitrogen with preserved planar structure.

DOI： 10.1021/acsanm.8b02237

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Molecular Technology: Materials Innovation  

DOI： 10.1002/9783527823987.vol3_c7

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：Carbohydrate Polymers  

The cassava starch processing plays an important role in food industries. During starch processing stage, a large amount of cassava starch waste (CSW) which mainly contains lost starch product and solid residue such as cassava bagasse are produced. Starch and cassava bagasse can be hydrolyzed into fermentable sugar such as glucose. In the present study, the solution plasma process (SPP) is used to treat CSW to prepare reducing sugar. The investigated parameters are treatment time, solvent concentration, applied pulsed frequency, and CSW concentration. The %yield of total reducing sugar (TRS) and glucose were calculated by DNS method and glucose assay kit, respectively. The chemical structure, morphology, and crystal structure of plasma-treated CSW were investigated. The results showed that the %yield of TRS was greatly enhanced by SPP treatment compared to that of acid hydrolysis. The CSW powder completely broke down into pieces after SPP treatment was applied. The amorphous and crystalline regions of CSW were destroyed during SPP treatment. SPP treatment of CSW with light sulfuric acid concentration of 0.08 M, applied pulsed frequency of 30 kHz, and CSW concentration of 0.5%w/v provided 99.0% TRS and 47.9% glucose.

DOI： 10.1016/j.carbpol.2018.10.090

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：IEEE-RAS International Conference on Humanoid Robots  

We propose a tool-use model that can select tools that require neither labeling nor modeling of the environment and actions. With this model, a robot can choose a tool by itself and perform the operation that matches a human command and the environmental situation. To realize this, we use deep learning to train sensory motor data recorded during tool selection and tool use as experienced by a robot. The experience includes two types of selection, namely according to function and according to size, thereby allowing the robot to handle both situations. For evaluation, the robot is required to generate motion either in an untrained situation or using an untrained tool. We confirm that the robot can choose and use a tool that is suitable for achieving the target task.

DOI： 10.1109/HUMANOIDS.2018.8625048

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：Journal of Occupational Health  

Objectives: Human support can boost weight reduction in Internet-based weight-loss intervention. However, the most effective way to combine human support and the Internet for weight loss is unclear. This study aimed to examine the effects of two weight-loss programs for male workers aged 18-39 that combined different intensities of human support with website support compared to a delayed-intervention group (control group; CG), in a randomized controlled trial. Methods: Seventy-one participants with overweight or obesity were allocated to one of three 12-week treatment programs. The Standard Support Group (SSG) was provided support via website and two face-to-face group guidance sessions, at the beginning and at the end of the program along with monthly general emails throughout the program. The Enhanced Support Group (ESG) received four remote support sessions based on Supportive Accountability (SA) in addition to the SSG. The CG was provided the same program as SSG after the other two groups had completed the program. The primary outcome was body weight reduction. Results: ESG participants reduced their weight significantly more than SSG and CG participants (P = 0.038, P < 0.001, respectively), and SSG participants reduced their weight significantly more than CG participants (P = 0.033). Conclusions: The additional remote human support provided to the participants in the ESG was beneficial for weight loss in male workers. The low-intensity program provided to the SSG was also effective. Further studies with more participants in diverse settings and with participants who are less interested in their health and weight management are needed.

DOI： 10.1002/1348-9585.12037

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Water Science and Technology  

DOI： 10.2166/wst.2019.035

Scopus

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

DOI： 10.1039/c9ta01751h

Scopus

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

DOI： 10.1155/2019/7494292

Web of Science

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Water Science and Technology  

DOI： 10.2166/wst.2019.035

Scopus

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

DOI： 10.1039/c9ta01751h

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：Carbohydrate Polymers  

Chitosan oligosaccharides, which obtain from degradation of chitosan, possess some interesting molecular weight-dependent biological properties, especially anticancer activity. Therefore, the conversion of chitosan to chitosan oligosaccharides with specific molecular weight has been continuously investigated in order to find effective strategies that can achieve both economic feasibility and environmental concerns. In this study, a novel process was developed to heterogeneously degrade chitosan powder by highly active species generated by electrical discharge plasma in a dilute salt solution (0.02 M) without the addition of other chemicals. The degradation rate obtained from the proposed process was comparable to that obtained from some other methods with the addition of acids and oxidizing agents. Separation of the water-soluble degraded products containing chitosan oligosaccharides from the reaction solution was simply done by filtration. The obtained chitosan oligosaccharides were further evaluated for an influence of their molecular weights on cytotoxicity against cancer cells and the selectivity toward cancer and normal cells.

DOI： 10.1016/j.carbpol.2018.08.037

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Photochemistry and Photobiology A: Chemistry  

DOI： 10.1016/j.jphotochem.2018.08.030

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Photochemistry and Photobiology A: Chemistry  

DOI： 10.1016/j.jphotochem.2018.08.030

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：MHS 2018 - 2018 29th International Symposium on Micro-NanoMechatronics and Human Science  

We developed 'Bionic Brain' which was equipped with cranial base module to train for transsphenoidal surgery. In the transsphenoidal surgery training by using this Bionic Brain, the user can insert an endoscope and a curette into the nose and sphenoid sinus, and remove tumors from the pituitary gland. From pseud surgery by brain surgeon, we confirmed that the fabricated cranial base module was similar to the anatomical structure.

DOI： 10.1109/MHS.2018.8886922

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 Alloys and Compounds  

Defective black titania (TiO2) was synthesized by the solution plasma technique at ambient temperature and pressure. The effects of the electrolyte solution medium type (KCl and HNO3) and concentration (0.3 and 3.0 mM) as well as the plasma discharge time (1–4 h) with a Ti electrode were investigated. The 3.0 mM HNO3 solution provided the highest energy per second discharging into the plasma, resulting in both a high synthesis rate of black TiO2 and a high degree of defective structures, as monitored in terms of the Ti3+/Ti4+ ratio, which can shorten the band gap energy (Eg) of the obtained black TiO2. A long plasma discharge time (4 h) induced the formation of large particles of black TiO2, which appeared as a highly defective structure. Overall, the black TiO2 prepared by discharged plasma for 4 h in 3.0 mM HNO3 solution (BTN-304) provided the highest photocatalytic activity for glycerol conversion (58.49% at 24 h) and 4.85, 3.32, 2.11, 2.15, 39.15 and 26.61% yield of glyceraldehyde, dihydroxyacetone, hydroxypyruvic acid, glycolic acid, glycolaldehyde and formaldehyde, respectively. Pathway of glycerol conversion and product distribution over black TiO2 was attempted to propose. Finally, the reusability of the best black TiO2 was explored.

DOI： 10.1016/j.jallcom.2018.05.046

Web of Science

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：Crystal Research and Technology  

DOI： 10.1002/crat.201700211

Web of Science

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：Physical Review C  

We present measurements of two-particle angular correlations between high-transverse-momentum (2<pT<11 GeV/c) π0 observed at midrapidity (|η|<0.35) and particles produced either at forward (3.1<η<3.9) or backward (-3.7<η<-3.1) rapidity in d+Au and p+p collisions at sNN=200 GeV. The azimuthal angle correlations for particle pairs with this large rapidity gap in the Au-going direction exhibit a characteristic structure that persists up to pT≈6 GeV/c and which strongly depends on collision centrality, which is a similar characteristic to the hydrodynamical particle flow in A+A collisions. The structure is absent in the d-going direction as well as in p+p collisions, in the transverse-momentum range studied. The results indicate that the structure is shifted in the Au-going direction toward more central collisions, similar to the charged-particle pseudorapidity distributions.

DOI： 10.1103/PhysRevC.98.014912

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：ChemistrySelect  

DOI： 10.1002/slct.201800851

Web of Science

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1166/nnl.2018.2719

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1166/nnl.2018.2716

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1166/nnl.2018.2655

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：Nanomaterials  

In this study, sol-immobilization was used to prepare gold nanoparticle (Au NP)-decorated titanium dioxide (TiO2) photocatalysts at different Au weight % (wt. %) loading (Aux/TiO2, where x is the Au wt. %) and Au–M NP-decorated TiO2 photocatalysts (Au3M3/TiO2), where M is bismuth (Bi), platinum (Pt) or palladium (Pd) at 3 wt. %. The Aux/TiO2 photocatalysts exhibited a stronger visible light absorption than the parent TiO2 due to the localized surface plasmon resonance effect. Increasing the Au content from 1 wt. % to 7 wt. % led to increased visible light absorption due to the increasing presence of defective structures that were capable of enhancing the photocatalytic activity of the as-prepared catalyst. The addition of Pt and Pd coupled with the Au3/TiO2 to form Au3M3/TiO2 improved the photocatalytic activity of the Au3/TiO2 photocatalyst by maximizing their light-absorption property. The Au3/TiO2, Au3Pt3/TiO2 and Au3Pd3/TiO2 photocatalysts promoted the formation of glyceraldehyde from glycerol as the principle product, while Au3Bi3/TiO2 facilitated glycolaldehyde formation as the major product. Among all the prepared photocatalysts, Au3Pd3/TiO2 exhibited the highest photocatalytic activity with a 98.75% glycerol conversion at 24 h of reaction time.

DOI： 10.3390/nano8040269

Web of Science

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：Beilstein Journal of Organic Chemistry  

Conscious of the potential bioactivity of fluorine, an investigation was conducted using various fluorine-containing diaryliodonium salts in order to study and compare their biological activity against human lymphoma U937 cells. Most of the compounds tested are well-known reagents for fluoro-functionalized arylation reactions in synthetic organic chemistry, but their biological properties are not fully understood. Herein, after initially investigating 18 fluoro-functionalized reagents, we discovered that the ortho-fluorofunctionalized diaryliodonium salt reagents showed remarkable cytotoxicity in vitro. These results led us to synthesize more compounds, previously unknown sterically demanding diaryliodonium salts having a pentafluorosulfanyl (SF5) functional group at the ortho-position, that is, unsymmetrical ortho-SF5 phenylaryl-λ3-iodonium salts. Newly synthesized mesityl(2-(pentafluoro-λ6-sulfanyl)phenyl)iodonium exhibited the greatest potency in vitro against U937 cells. Evaluation of the cytotoxicity of selected phenylaryl-λ3-iodonium salts against AGLCL (a normal human B cell line) was also examined.

DOI： 10.3762/bjoc.14.24

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：Japanese Journal of Applied Physics  

Chitosan is a polysaccharide that has been extensively studied in the field of biomedicine, especially its water-soluble degraded products called chitooligosaccharides (COS). In this study, COS were produced by the degradation of chitosan hydrogel dispersed in a dilute solution (i.e., 1.55 mM) of various kinds of carboxylic acids using a non-thermal plasma technology called solution plasma (SP). The degradation rates of chitosan were influenced by the type of carboxylic acids, depending on the interaction between chitosan and each carboxylic acid. After SP treatment, the water-soluble degraded products containing COS could be easily separated from the water-insoluble residue of chitosan hydrogel by centrifugation. The production yields of the COS were mostly higher than 55%. Furthermore, the obtained COS products were evaluated for their inhibitory effect as well as their selectivity against human lung cancer cells (H460) and human lung normal cells (MRC-5).

DOI： 10.7567/JJAP.57.0102B5

Web of Science

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：Japanese Journal of Applied Physics  

Silicon has been attracting attention as an anode material that can be used for the design of high-capacity lithium ion batteries (LIB). However, the long-term cycling performance of silicon is limited owing to exfoliation from the current collector, resulting from volumetric expansion upon alloying with lithium in the charging process. However, carbon black is an agglomerate of primary particles that form a network and can incorporate a sufficient void space between network structures to accommodate the volumetric expansion of silicon. In this study, we propose the possibility of preventing the volume expansion and exfoliation of silicon by capturing silicon nanoparticles in the void space of the carbon black network. A silicon-carbon black composite material with this structure was successfully synthesized by solution plasma processing.

DOI： 10.7567/JJAP.57.0102B2

Web of Science

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：Japanese Journal of Applied Physics  

DOI： 10.7567/JJAP.57.0102A4

Web of Science

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：Japanese Journal of Applied Physics  

DOI： 10.7567/JJAP.57.0102A3

Web of Science

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：Japanese Journal of Applied Physics  

DOI： 10.7567/JJAP.57.010201

Web of Science

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：Japanese Journal of Applied Physics  

Carbon black nanoparticles (CB-NPs) have been synthesized from liquid benzene by a solution plasma method at room temperature and atmospheric pressure. The morphological observation by scanning electron microscopy revealed the agglomeration of aggregated fine particles. The synthesized CB-NPs were predominantly amorphous as confirmed by X-ray diffraction. The in vitro cytotoxicity of CB-NPs on the human lung fibroblast (MRC-5) cell line was assessed by the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and systematically compared with those of two types of commercial carbon blacks (i.e., Vulcan XC-72 and Ketjenblack EC-600JD). Cell viabilities were studied at different concentrations of 32.5, 65, 125, and 250 μg/mL. It was found that the CB-NPs derived from solution plasma exhibited a lower cytotoxicity on the MRC-5 cells than the other two comparative carbon blacks. The viability of MRC-5 cells exposed to CB-NPs remained higher than 90% even at a high concentration of 250 μg/mL. This result preliminarily confirmed the biosafety and potential use of CB-NPs in the field of biological applications.

DOI： 10.7567/JJAP.57.0102BG

Web of Science

Scopus

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

DOI： 10.1039/c8ra06614k

Web of Science

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：一般社団法人 日本物理学会  

DOI： 10.11316/jpsgaiyo.73.1.0_1800

CiNii Research

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

DOI： 10.1039/c8ra06614k

Web of Science

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：Chemical Science  

The trans-tetrafluoro-λ6-sulfane (SF4) group has been utilized as a unique three-dimensional building block for the linear connection of two independent N-heterocycles, pyridines and triazoles. The linearly connected heterocyclic compounds were synthesized by thermal Huisgen 1,3-dipolar cycloaddition between previously unknown pyridine SF4-alkynes and readily available azides, providing a series of rod-like SF4-connected N-heterocycles in good to excellent yields. X-ray crystallographic analysis of the target products revealed the trans-geometry of the SF4 group, which linearly connects two independent N-heterocycles. This research will open the field of chemistry of SF4-connected heterocyclic compounds.

DOI： 10.1039/c8sc01216d

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 Alloys and Compounds  

DOI： 10.1016/j.jallcom.2017.08.028

Web of Science

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：ACS Omega  

We report a simple room-temperature synthesis route for increasing the reactivity of a TiO2 photocatalyst using a solution plasma process (SPP). Hydrogen radicals generated from the SPP chamber interact with the TiO2 photocatalyst feedstock, transforming its crystalline phase and introducing oxygen vacancy defects. In this work, we examined a pure anatase TiO2 as a model feedstock because of its photocatalytic attributes and well-characterized properties. After the SPP treatment, the pure anatase crystalline phase was transformed to an anatase/brookite heterocrystalline phase with oxygen vacancies. Furthermore, the SPP treatment promoted the absorption of both UV and visible light by TiO2. As a result, TiO2 treated by the SPP for 3 h showed a high gaseous photocatalytic performance (91.1%) for acetaldehyde degradation to CO2 compared with the activity of untreated TiO2 (51%). The SPP-treated TiO2 was also more active than nitrogen-doped TiO2 driven by visible light (66%). The overall photocatalytic performance was related to the SPP treatment time. The SPP technique could be used to enhance the activity of readily available feedstocks with a short processing time. These results demonstrate the potential of this method for modifying narrow-band gap metal oxides, metal sulfides, and polymer composite-based catalyst materials. The modifications of these materials are not limited to photocatalysts and could be used in a wide range of energy and environment-based applications.

DOI： 10.1021/acsomega.7b01698

Web of Science

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：Nuclear Physics A  

DOI： 10.1016/S0375-9474(17)30382-2

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 Physical Chemistry C  

DOI： 10.1021/acs.jpcc.7b08516

Web of Science

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：Japanese Journal of Applied Physics  

DOI： 10.7567/JJAP.56.096202

Web of Science

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：Physical Review C  

We report a measurement of e+e- pairs from semileptonic heavy-flavor decays in p+p collisions at sNN=200 GeV. The e+e- pair yield from bb and cc is separated by exploiting a double differential fit done simultaneously in dielectron invariant mass and pT. We used three different event generators, pythia, mc@nlo, and powheg, to simulate the e+e- spectra from cc and bb production. The data can be well described by all three generators within the detector acceptance. However, when using the generators to extrapolate to 4π, significant differences are observed for the total cross section. These difference are less pronounced for bb than for cc. The same model dependence was observed in already published d+A data. The p+p data are also directly compared with d+A data in mass and pT, and within the statistical accuracy no nuclear modification is seen.

DOI： 10.1103/PhysRevC.96.024907

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：Plasma Processes and Polymers  

Solution plasma process has been researched as one of the synthetic methods of nano- and functional materials using plasma discharge in liquids. In this study, a low-pass filter circuit was introduced to increase the density and temperature of electrons involved in a non-equilibrium condition. The discharge properties of the solution plasma generated by conventional and low-pass filter circuits were characterized and comparatively analyzed. Filtration of the MHz range current oscillations, an increase in the maximum discharge current, and a higher stability of solution plasma were obtained by simply inserting a resistor-capacitor (RC) component in the circuit, which leads to the increases in the density and temperature of electrons.

DOI： 10.1002/ppap.201600163

Web of Science

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：ACS Sustainable Chemistry and Engineering  

DOI： 10.1021/acssuschemeng.7b00560

Web of Science

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：Scientific Reports  

DOI： 10.1038/s41598-017-04190-x

Web of Science

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：Optics Express  

An Nd:YAG laser-based sodium temperature/wind lidar was developed for the measurement of the northern polar mesosphere and lower thermosphere at Tromsø (69.6N, 19.2E), Norway. Coherent light at 589 nm is produced by sum frequency generation of 1064 nm and 1319 nm from two diode laser end-pumped pulsed Nd:YAG lasers. The output power is as high as 4W, with 4 mJ/pulse at 1000 Hz repetition rate. Five tilting Cassegrain telescopes enable us to make five-direction (zenith, north, south, east, west) observation for temperature and wind simultaneously. This highly stable laser system is first of its kind to operate virtually maintenance-free during the observation season (from late September to March) since 2010.

DOI： 10.1364/OE.25.00A491

Web of Science

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：Physical Chemistry Chemical Physics  

Synthesis of boron-carbon-nitrogen (BCN) nanocarbon with a controllable bond structure for enhanced oxygen reduction reaction (ORR) activity and durability was performed using a new method of discharge in organic solution mixtures named the 'Solution Plasma Process'. Using selected precursors a new strategy for the simultaneous synthesis of nanocarbon co-doped with heteroatoms was found. The synergistic effect of N and B in an uncoupling bond state improved the formation of new active sites for the ORR performance by changing the electronic structure of the base carbon. Meanwhile, when B and N are bonded together, the BCN catalyst contributes to a reduced ORR activity by forming a balanced electronic structure in carbon. The BCN nanocarbon with an uncoupling bond state exhibits an enhanced ORR activity under alkaline conditions, with an onset potential of -0.25 V versus -0.31 V for B/N coupling and 3.43 transferred electrons during the ORR. Although the ORR activity of the B/N uncoupling nanocarbon was not as good as the typical Pt/C, the durability of this synthesized material (15.1% current decrease after 20000 s of operation) was significantly better than that of the Pt/C catalyst (61.5% current drop under the same conditions). After the durability test, the increase of the chemical states containing oxygen was higher for Pt/C than B/N uncoupling.

DOI： 10.1039/c6cp06063c

Web of Science

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：Molecular Catalysis  

DOI： 10.1016/j.mcat.2017.02.022

Web of Science

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：Biochemistry and Biophysics Reports  

We previously reported that ubiquitin-specific protease (USP) 2 in macrophages down-regulates genes associated with metabolic diseases, suggesting a putative anti-diabetic role for USP2 in macrophages. In this study, we evaluate this role at both cellular and individual levels. Isolated macrophages forcibly expressing Usp2a, a longer splicing variant of USP2, failed to modulate the insulin sensitivity of 3T3-L1 adipocytes. Similarly, macrophage-selective overexpression of Usp2a in mice (Usp2a transgenic mice) had a negligible effect on insulin sensitivity relative to wild type littermates following a three-month high-fat diet. However, Usp2a transgenic mice exhibited fewer M1 macrophages in their mesenteric adipose tissue. Following a six-month high-fat diet, Usp2a transgenic mice exhibited a retarded progression of insulin resistance in their skeletal muscle and liver, and an improvement in insulin sensitivity at an individual level. Although conditioned media from Usp2a-overexpressing macrophages did not directly affect the insulin sensitivity of C2C12 myotubes compared to media from control macrophages, they did increase the insulin sensitivity of C2C12 cells after subsequent conditioning with 3T3-L1 cells. These results indicate that macrophage USP2A hampers obesity-elicited insulin resistance via an adipocyte-dependent mechanism.

DOI： 10.1016/j.bbrep.2017.01.009

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：Genes to Cells  

In the mammalian global genome nucleotide excision repair pathway, two damage recognition factors, XPC and UV-DDB, play pivotal roles in the initiation of the repair reaction. However, the molecular mechanisms underlying regulation of the lesion recognition process in the context of chromatin structures remain to be understood. Here, we show evidence that damage recognition factors tend to associate with chromatin regions devoid of certain types of acetylated histones. Treatment of cells with histone deacetylase inhibitors retarded recruitment of XPC to sites of UV-induced DNA damage and the subsequent repair process. Biochemical studies showed novel multifaceted interactions of XPC with histone H3, which were profoundly impaired by deletion of the N-terminal tail of histone H3. In addition, histone H1 also interacted with XPC. Importantly, acetylation of histone H3 markedly attenuated the interaction with XPC in vitro, and local UV irradiation of cells decreased the level of H3K27ac in the damaged areas. Our results suggest that histone deacetylation plays a significant role in the process of DNA damage recognition for nucleotide excision repair and that the localization and functions of XPC can be regulated by acetylated states of histones.

DOI： 10.1111/gtc.12479

Scopus

掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.carbpol.2017.05.025

掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.electacta.2017.03.049

掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jallcom.2016.09.032

掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jallcom.2017.03.202

掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jallcom.2016.10.200

掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/app.44903

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：Energy Procedia  

Green liquid fuels are alternatively produced by pyrolysis of vegetable oil. Still, this process requires high processing temperature and high energy consumption per unit cost. Recently, solution/liquid-phase plasma (cold plasma) is the novel method to provide the direct energy at highly excited energy state. In this study, the investigation of the green fuel synthesis from vegetables oils using cold plasma was examined. The cold plasma reactor was connected to a bipolar pulsed power supply under 200 ml of palm oil, the pulse frequency adjusted from 15-45 kHz and the voltage adjusted in ranges of 1.2-1.5 kV with 40 minutes of discharge times, pulse width 2 μs, electrode distance 0.5 mm. Properties of generated plasma were investigated by optical emission spectroscopy (OES) methods. The liquid products were analysed by GC-MS. In order to identify components of the liquid product, a GC-MS chromatogram was carried out; the main peaks were oleic acid and palmitic acid. Therefore, the other peak showed which products were cracked to short-chain hydrocarbon and hexadecane was one of the compounds which were cracked in palm oil. In conclusion, the results showed that plasma has potential and enough energy to convert vegetable oils in liquid fuels at room temperature which can also provide the direct energy better than pyrolysis.

DOI： 10.1016/j.egypro.2017.10.224

Web of Science

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Key Engineering Materials  

DOI： 10.4028/www.scientific.net/KEM.751.773

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本表面科学会  

ソリューションプラズマを用いた金属ナノ粒子や燃料電池用カーボン触媒の合成について紹介する

DOI： 10.14886/sssj2008.37.0_27

掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 表面技術協会  

<p>Nanocarbons were synthesized from benzene - water - sodium dodecyl sulfate（SDS）and benzene-（water-ethanol）-SDS systems using solution plasma. The stabilized emulsion formed in the benzene-water-SDS and benzene-（water-ethanol）-SDS. The specific surface areas of nanocarbons synthesized from benzene-water-SDS increased with the increase of the SDS concentration, although their variation was not great. By contrast, the surface areas of nanocarbons synthesized from benzene-（water-ethanol）-SDS were altered considerably compared to the variation in benzene-（water-ethanol）-SDS system. The maximum specific surface area was 387 m²/g. The minimum averaged pore size was 13.5 nm when the ratio of ethanol to water was 0.5. That fact suggests that the emulsion size of 50-100 nm influences the meso-structures of the obtained carbon in solution plasma processes.</p>

DOI： 10.4139/sfj.68.153

掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 表面技術協会  

<p>The optical and electronic performance of zinc oxide nanoparticles, which are widely used as optical and electronic materials, depends on the nanoparticle properties. The particle size is a particularly important factor affecting material properties. This study was conducted to elucidate the relation between the size of nanoparticles synthesized by solution plasma and each of several plasma formation parameters such as applied voltage, pulse width, and repetition frequency. The zinc electrodes were used to generate solution plasma. The zinc oxide nanoparticles were synthesized in solution plasma using a sputtering process. The synthesized nanoparticle shape was non-spherical. The nanoparticles were smaller than 100 nm along the long axis. Electrode sputtering occurred mainly on the cathode electrode. Therefore, positive ions in the solution plasma, e.g. H₂O⁺ and H₃O⁺, affect the zinc oxide nanoparticle formation. However, the particle size was correlated with the applied voltage between electrodes, not with the pulse width or pulse repetition frequency.</p>

DOI： 10.4139/sfj.68.147

掲載種別：研究論文（学術雑誌）   出版者・発行元：Key Engineering Materials  

DOI： 10.4028/www.scientific.net/KEM.751.773

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 表面技術協会  

<p>Nanocarbons were synthesized from benzene - water - sodium dodecyl sulfate（SDS）and benzene-（water-ethanol）-SDS systems using solution plasma. The stabilized emulsion formed in the benzene-water-SDS and benzene-（water-ethanol）-SDS. The specific surface areas of nanocarbons synthesized from benzene-water-SDS increased with the increase of the SDS concentration, although their variation was not great. By contrast, the surface areas of nanocarbons synthesized from benzene-（water-ethanol）-SDS were altered considerably compared to the variation in benzene-（water-ethanol）-SDS system. The maximum specific surface area was 387 m²/g. The minimum averaged pore size was 13.5 nm when the ratio of ethanol to water was 0.5. That fact suggests that the emulsion size of 50-100 nm influences the meso-structures of the obtained carbon in solution plasma processes.</p>

DOI： 10.4139/sfj.68.153

掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 表面技術協会  

<p>The optical and electronic performance of zinc oxide nanoparticles, which are widely used as optical and electronic materials, depends on the nanoparticle properties. The particle size is a particularly important factor affecting material properties. This study was conducted to elucidate the relation between the size of nanoparticles synthesized by solution plasma and each of several plasma formation parameters such as applied voltage, pulse width, and repetition frequency. The zinc electrodes were used to generate solution plasma. The zinc oxide nanoparticles were synthesized in solution plasma using a sputtering process. The synthesized nanoparticle shape was non-spherical. The nanoparticles were smaller than 100 nm along the long axis. Electrode sputtering occurred mainly on the cathode electrode. Therefore, positive ions in the solution plasma, e.g. H₂O⁺ and H₃O⁺, affect the zinc oxide nanoparticle formation. However, the particle size was correlated with the applied voltage between electrodes, not with the pulse width or pulse repetition frequency.</p>

DOI： 10.4139/sfj.68.147

掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本表面科学会  

ソリューションプラズマを用いた金属ナノ粒子や燃料電池用カーボン触媒の合成について紹介する

DOI： 10.14886/sssj2008.37.0_27

掲載種別：研究論文（学術雑誌）   出版者・発行元：Scientific Reports  

DOI： 10.1038/srep38652

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Scientific Reports  

DOI： 10.1038/srep38652

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：Nuclear Physics A  

DOI： 10.1016/S0375-9474(16)30234-2

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：Scientific Reports  

Although solution-plasma processing enables room-temperature synthesis of nanocarbons, the underlying mechanisms are not well understood. We investigated the routes of solution-plasma-induced nanocarbon formation from hexane, hexadecane, cyclohexane, and benzene. The synthesis rate from benzene was the highest. However, the nanocarbons from linear molecules were more crystalline than those from ring molecules. Linear molecules decomposed into shorter olefins, whereas ring molecules were reconstructed in the plasma. In the saturated ring molecules, C-H dissociation proceeded, followed by conversion into unsaturated ring molecules. However, unsaturated ring molecules were directly polymerized through cation radicals, such as benzene radical cation, and were converted into two- and three-ring molecules at the plasma-solution interface. The nanocarbons from linear molecules were synthesized in plasma from small molecules such as C2 under heat; the obtained products were the same as those obtained via pyrolysis synthesis. Conversely, the nanocarbons obtained from ring molecules were directly synthesized through an intermediate, such as benzene radical cation, at the interface between plasma and solution, resulting in the same products as those obtained via polymerization. These two different reaction fields provide a reasonable explanation for the fastest synthesis rate observed in the case of benzene.

DOI： 10.1038/srep36880

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：Cuihua Xuebao/Chinese Journal of Catalysis  

The effect of the electron acceptors H2O2 and O2 on the type of generated reactive oxygen species (ROS), and glycerol conversion and product distribution in the TiO2-catalyzed photocatalytic oxidation of glycerol was studied at ambient conditions. In the absence of an electron acceptor, only HO· radicals were generated by irradiated UV light and TiO2. However, in the presence of the two electron acceptors, both HO· radical and 1O2 were produced by irradiated UV light and TiO2 in different concentrations that depended on the concentration of the electron acceptor. The use of H2O2 as an electron acceptor enhanced glycerol conversion more than O2. The type of generated value-added compounds depended on the concentration of the generated ROS.

DOI： 10.1016/S1872-2067(16)62519-6

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：Journal of Chemical Neuroanatomy  

The bed nucleus of the stria terminalis pars medialis (BSTM), medial preoptic nucleus (POM), and lateral septal region (LS) exhibit more vasotocin-immunoreactive (VT-ir) neural structures in male than in female adult quail. VT-ir cells and fibers in these regions are sensitive to gonadal steroids only in males. The insensitivity of adult female VT-ir neural structures to sex steroids is attributed to estradiol exposure during a critical period in embryonic life.Although the VT-ir system has been intensively examined in adult quail, information is limited in embryos and juveniles. Therefore, we herein investigated the development of VT-immunoreactive neural structures from embryonic day (E) 9 to adulthood with a particular focus on the BSTM, POM and LS of both sexes.VT-ir neural structures were more evident in female than in male embryos from E9 (BSTM and POM) and E11 (LS). This sex difference disappeared between E15 and post-hatch day 1 in the BSTM and POM, and during the first week of life in the LS. Male-biased sex differences in VT-ir structures appeared at puberty. Female-biased sexual dimorphism in the density of the VT-ir structures of BSTM was reflected by the stronger expression of VT mRNA in females than in males. However, the density of VT mRNA somata was comparable in the two sexes.The exposure of male embryos to estradiol resulted in the feminization of VT-ir neural structures in the BSTM, but not in the POM or LS at E11.Collectively, these results suggest that sex differences in VT-ir neural structures changes drastically throughout quail life. In embryos, endogenous estradiol may stimulate the expression of VT in females, resulting in a robust sex difference in VT-ir cells and fibers in favor of this sex.

DOI： 10.1016/j.jchemneu.2016.05.002

Web of Science

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：Scientific Reports  

Although empathy is important for social interactions, individuals with alexithymia have low empathic ability, particularly where advanced empathy is concerned (empathic concern, perspective taking). It has been argued that awareness of the self-other distinction enhances advanced empathy, and alexithymics are thought to inadequately distinguish the self from others. We therefore tested whether the self-other distinction increases advanced empathy in alexithymics. To this end, we presented painful hand images over participants' own hands, and required participants to estimate felt pain intensity and their affective states. Half of the participants got specific instructions to distinct themselves from the other in the images. Felt pain intensity (perspective taking) and other-oriented affective responses (empathic concern) were increased by the instructions only when participants had high alexithymia scores as measured by questionnaire, although self-oriented affective responses (personal distress) were not affected by the instructions. These findings indicate that enhancing the self-other distinction enhances alexithymics' ability to use advanced empathy, but not the primitive empathy.

DOI： 10.1038/srep35059

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：Journal of Physics D: Applied Physics  

We used ab initio molecular orbital (MO) calculations to study the differences in the intermediate structures and the electronic states involved in the adsorption of O2 onto 13-atom metal clusters of Pt, Cu, and Au. Additionally, the conditions required for the electrocatalytic oxygen reduction reaction (ORR) on the Pt, Cu, and Au clusters were investigated and discussed. The intermediates involved in O2 adsorption onto Pt, Cu, and Au were found to be (Pt-O)-(Pt-O), Cu-O, and Au-O2, respectively. The differences in the O2 adsorption intermediates is explained on the basis of our analysis of the projected density of state (PDOS) area of the new MOs produced from a mixture of the 2pπ ∗ orbitals of O2 and the d orbitals of the metal clusters. The formation of the (Pt-O)-(Pt-O) intermediate after the adsorption of O2 onto the Pt cluster is attributed to the emergence of an antibonding orbital above the Fermi level. Thus, this electronic state can lead to the decomposition and desorption of O2 molecules, thereby promoting the high-activity level of ORR. For the Cu cluster, a new antibonding orbital was observed below the Fermi level. Moreover, the Cu cluster surface can only promote O2 decomposition and not O2 desorption due to the formation of copper oxides. For the Au cluster, no new MOs related to 2pπ ∗ orbitals of O2 appeared because O2 was molecularly adsorbed, implying that the Au cluster is an inefficient ORR catalyst.

DOI： 10.1088/0022-3727/49/41/415305

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Structural Health Monitoring Technologies and Next-Generation Smart Composite Structures  

DOI： 10.4324/9781315373492

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：Carbohydrate Polymers  

Zinc oxide (ZnO) was successfully synthesized by applying a solution plasma, a plasma discharge in a liquid phase, without the addition of a reducing agent and simultaneously deposited into a bacterial cellulose pellicle that functioned as a template. By the reasons of its nano-sized structure as well as favorable porous configuration, the BC pellicle has been proved to be a splendid upholding template for the coordination of ZnO. In addition, the ZnO-deposited BC composites demonstrated strong antibacterial activity without a photocatalytic reaction against both Staphylococcus aureus and Escherichia coli. Hence, the ZnO-deposited BC composites can be used as an antibacterial material in wound dressing and water disinfection applications.

DOI： 10.1016/j.carbpol.2016.04.066

Web of Science

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：Science Advances  

Atypical neurodevelopment in autism spectrum disorder is a mystery, defying explanation despite increasing attention. We report on a Japanese macaque that spontaneously exhibited autistic traits, namely, impaired social ability as well as restricted and repetitive behaviors, along with our single-neuron and genomic analyses. Its social ability was measured in a turn-taking task, where two monkeys monitor each other’s actions for adaptive behavioral planning. In its brain, the medial frontal neurons responding to others’ actions, abundant in the controls, were almost nonexistent. In its genes, whole-exome sequencing and copy number variation analyses identified rare coding variants linked to human neuropsychiatric disorders in 5-hydroxytryptamine (serotonin) receptor 2C (HTR2C) and adenosine triphosphate (ATP)–binding cassette subfamily A13 (ABCA13). This combination of systems neuroscience and cognitive genomics in macaques suggests a new, phenotype-to-genotype approach to studying mental disorders.

DOI： 10.1126/sciadv.1600558

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：Physical Review C  

Measurements of the anisotropic flow coefficients v2{Ψ2},v3{Ψ3},v4{Ψ4}, and v4{Ψ2} for identified particles (π±,K±, and p+p) at midrapidity, obtained relative to the event planes Ψm at forward rapidities in Au + Au collisions at sNN=200GeV, are presented as a function of collision centrality and particle transverse momenta pT. The vn coefficients show characteristic patterns consistent with hydrodynamical expansion of the matter produced in the collisions. For each harmonic n, a modified valence quark-number Nq scaling [plotting vn{Ψm}/(Nq)n/2 versus transverse kinetic energies (KET)/Nq] is observed to yield a single curve for all the measured particle species for a broad range of KET. A simultaneous blast-wave model fit to the observed vn{Ψm}(pT) coefficients and published particle spectra identifies radial flow anisotropies ρn{Ψm} and spatial eccentricities sn{Ψm} at freeze-out. These are generally smaller than the initial-state participant-plane geometric eccentricities n{ΨmPP} as also observed in the final eccentricity from quantum interferometry measurements with respect to the event plane.

DOI： 10.1103/PhysRevC.93.051902

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：JOM  

DOI： 10.1007/s11837-016-1826-0

Web of Science

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：Physical Chemistry Chemical Physics  

Heterocarbon nanosheets incorporating iron phthalocyanine (FP-NCNs-SP) have been successfully synthesized by a facile one-pot solution plasma process at high repetition frequency. It was found that the Fe-N4 catalytic active sites could be preserved on the FP-NCNs-SP without degradation. The FP-NCNs-SP also possessed large surface area, good conductivity and high degree of graphitization. Electrochemical evaluations demonstrated that NCNs-SP had excellent electrocatalytic activity and selectivity toward oxygen reduction reaction (ORR) in alkaline medium through a direct four-electron pathway. Although the significant improvement in ORR activity was clearly observed in acidic medium, it was much poorer than in alkaline medium. We believe that the results presented in this work will shed light on the advanced synthesis and design of ORR electrocatalysts at room temperature with an abundance of catalytically active sites and high ORR performance.

DOI： 10.1039/c5cp07739g

Web of Science

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：International Journal of Plasma Environmental Science and Technology  

This research reported an innovative method to synthesize inexpensive and bi-functional catalyst electrode material for the application in Li-air battery. Non-novel metal, Cu and Fe were served, respectively, as alternative Oxygen Reduction Reaction (ORR) and Oxygen Evolution Reaction (OER). Solution Plasma Process was applied to synthesized Cu-Fe metal nanoparticles and carbon nanoparticles simultaneously. SPP was generated in benzene 100 mL using a bipolar pulse power supply. Iron and copper of diameter 1.0 mm were used for the discharge electrode and precursor of the bimetallic nanoparticles. Solution was reacted and stirred continuously for 20 minutes. Based on the amount of electrode consumption and ICP-AES analysis, the percentage of Cu and Fe supported on carbon were respectively, 2.8 and 1.0 wt%. The diameter of metal nanoparticles was approximately 10 nm, where the carbon nanoparticles ranged between 20-30 nm. From XRD analyses, the presences of Cu, Fe and CuFe2O4 were confirmed. In the performance of cyclic voltammetry, Fe and Cu nanoparticles showed the catalytic activity, respectively, for ORR and OER, at -0.38 and above 0.5 V. In the case of Fe-Cu bimetallic nanoparticles, it showed the combined catalytic activities of the single particles.

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：Carbon  

Metal-free nitrogen-doped carbon nanoparticles (NCNPs) have been synthesized via a solution plasma process with the potential to achieve uniformly distributed nitrogen atoms. A set of cyano-aromatic molecules, including benzonitrile, 2-cyanopyridine, and cyanopyrazine, were used as a single-source precursor in the synthesis without the addition of a metal catalyst source. The resultant NCNPs reveal uniformly nanosized particles (20-40 nm) and an interconnected hierarchical pore structure with a high specific surface area (210-250 m2 g-1). The difference in carbon/nitrogen mole ratios of organic precursors gives rise to the variation of nitrogen-doping level in NCNPs from 0.63 to 1.94 atom %. Detailed electrochemical evaluation toward the oxygen reduction reaction (ORR) demonstrates that NCNPs exhibit a significant improvement in terms of both onset potential and current density under alkaline and acidic conditions. The predominant distribution of graphitic-N and pyridinic-N sites on NCNPs plays an essential role in enhancing the ORR activity and the selectivity toward a four-electron reduction pathway. More importantly, NCNPs possess excellent robust long-term durability and strong methanol tolerance compared with those of a commercial Pt/carbon catalyst.

DOI： 10.1016/j.carbon.2015.11.013

Web of Science

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：ACS Applied Materials and Interfaces  

Metal-free nitrogen-doped carbon materials are currently considered at the forefront of potential alternative cathode catalysts for the oxygen reduction reaction (ORR) in fuel cell technology. Despite numerous efforts in this area over the past decade, rational design and development of a new catalyst system based on nitrogen-doped carbon materials via an innovative approach still present intriguing challenges in ORR catalysis research. Herein, a new kind of nitrogen-doped carbon nanoparticle-carbon nanofiber (NCNP-CNF) composite with highly efficient and stable ORR catalytic activity has been developed via a new approach assisted by a solution plasma process. The integration of NCNPs and CNFs by the solution plasma process can lead to a unique morphological feature and modify physicochemical properties. The NCNP-CNF composite exhibits a significantly enhanced ORR activity through a dominant four-electron pathway in an alkaline solution. The enhancement in ORR activity of NCNP-CNF composite can be attributed to the synergistic effects of good electron transport from highly graphitized CNFs as well as abundance of exposed catalytic sites and meso/macroporosity from NCNPs. More importantly, NCNP-CNF composite reveals excellent long-term durability and high tolerance to methanol crossover compared with those of a commercial 20 wt % supported on Vulcan XC-72. We expect that NCNP-CNF composite prepared by this synthetic approach can be a promising metal-free cathode catalyst candidate for ORR in fuel cells and metal-air batteries.

DOI： 10.1021/acsami.5b10493

Web of Science

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：Physical Review C  

Measurements of the fractional momentum loss (Sloss≡δpT/pT) of high-transverse-momentum-identified hadrons in heavy-ion collisions are presented. Using π0 in Au+Au and Cu+Cu collisions at sNN=62.4 and 200 GeV measured by the PHENIX experiment at the Relativistic Heavy Ion Collider and and charged hadrons in Pb+Pb collisions measured by the ALICE experiment at the Large Hadron Collider, we studied the scaling properties of Sloss as a function of a number of variables: the number of participants, Npart, the number of quark participants, Nqp, the charged-particle density, dNch/dη, and the Bjorken energy density times the equilibration time, Bjτ0. We find that the pT, where Sloss has its maximum, varies both with centrality and collision energy. Above the maximum, Sloss tends to follow a power-law function with all four scaling variables. The data at sNN=200 GeV and 2.76 TeV, for sufficiently high particle densities, have a common scaling of Sloss with dNch/dη and Bjτ0, lending insight into the physics of parton energy loss.

DOI： 10.1103/PhysRevC.93.024911

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：Physical Review C  

Measurements of midrapidity charged-particle multiplicity distributions, dNch/dη, and midrapidity transverse-energy distributions, dET/dη, are presented for a variety of collision systems and energies. Included are distributions for Au+Au collisions at sNN=200, 130, 62.4, 39, 27, 19.6, 14.5, and 7.7 GeV, Cu+Cu collisions at sNN=200 and 62.4 GeV, Cu+Au collisions at sNN=200 GeV, U+U collisions at sNN=193 GeV, d+Au collisions at sNN=200 GeV, He3+Au collisions at sNN=200 GeV, and p+p collisions at sNN=200 GeV. Centrality-dependent distributions at midrapidity are presented in terms of the number of nucleon participants, Npart, and the number of constituent quark participants, Nqp. For all A+A collisions down to sNN=7.7 GeV, it is observed that the midrapidity data are better described by scaling with Nqp than scaling with Npart. Also presented are estimates of the Bjorken energy density, BJ, and the ratio of dET/dη to dNch/dη, the latter of which is seen to be constant as a function of centrality for all systems.

DOI： 10.1103/PhysRevC.93.024901

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.surfcoat.2015.11.051

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：Physical Review C  

We report the measurement of cumulants (Cn,n=1,⋯,4) of the net-charge distributions measured within pseudorapidity (|η|<0.35) in Au+Au collisions at sNN=7.7-200GeV with the PHENIX experiment at the Relativistic Heavy Ion Collider. The ratios of cumulants (e.g., C1/C2, C3/C1) of the net-charge distributions, which can be related to volume independent susceptibility ratios, are studied as a function of centrality and energy. These quantities are important to understand the quantum-chromodynamics phase diagram and possible existence of a critical end point. The measured values are very well described by expectation from negative binomial distributions. We do not observe any nonmonotonic behavior in the ratios of the cumulants as a function of collision energy. The measured values of C1/C2 and C3/C1 can be directly compared to lattice quantum-chromodynamics calculations and thus allow extraction of both the chemical freeze-out temperature and the baryon chemical potential at each center-of-mass energy. The extracted baryon chemical potentials are in excellent agreement with a thermal-statistical analysis model.

DOI： 10.1103/PhysRevC.93.011901

Scopus

記述言語：日本語   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）   出版者・発行元：Journal of Instrumentation  

The decomposition of p-benzoquinone (p-BQ) in Solution Plasma Processing (SPP) was analyzed by Coherent Anti-Stokes Raman Spectroscopy (CARS) by monitoring the change of the anti-Stokes signal intensity of the vibrational transitions of the molecule, during and after SPP. Just in the beginning of the SPP treatment, the CARS signal intensities of the ring vibrational molecular transitions increased under the influence of the electric field of plasma. The results show that plasma influences the p-BQ molecules in two ways: (i) plasma produces a polarization and an orientation of the molecules in the local electric field of plasma and (ii) the gas phase plasma supplies, in the liquid phase, hydrogen and hydroxyl radicals, which reduce or oxidize the molecules, respectively, generating different carboxylic acids. The decomposition of p-BQ after SPP was confirmed by UV-visible absorption spectroscopy and liquid chromatography.

DOI： 10.1088/1748-0221/11/01/C01009

Web of Science

Scopus

その他リンク： http://orcid.org/0000-0001-8757-3933

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.7567/JJAP.55.01AE10

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.7567/JJAP.55.01AE10

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

DOI： 10.7567/JJAP.55.01AE17

Web of Science

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：Japanese Journal of Applied Physics  

Nitrogen-containing carbon nanoparticles were synthesized in aniline by solution plasma with high-repetition frequency discharges. We developed a bipolar pulsed power supply that can apply high-repetition frequencies ranging from 25 to 200 kHz. By utilizing high-repetition frequencies, conductive carbons were directly synthesized. The crystallinity was increased and H/C ratio of carbon was decreased. Furthermore, nitrogen atoms were simultaneously embedded in the carbon matrix. Due to the presence of nitrogen atoms, the conductivity and electrocatalytic activity of the samples were remarkably improved compared to that of a pure carbon matrix synthesized from a benzene precursor.

DOI： 10.7567/JJAP.55.01AE18

Web of Science

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：Japanese Journal of Applied Physics  

DOI： 10.7567/JJAP.55.01AE23

Web of Science

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：一般社団法人 資源・素材学会  

Solution plasma is a non-equilibrium plasma in liquid phase. The reaction field of solution plasma is novel and useful for a wide variety of material science and engineering applications.　Active species such as radicals, electrons and ions are generated in the plasma. These active species react with chemicals in liquid at the interface between plasma (gas) and liquid and cause unique chemical reactions owing to variation of liquids, electrodes, as well as operational conditions.　Until now, solution plasma process has been applied into the following applications; (1) nanoparticle synthesis, (2) surface modification of nanocarbon, (3) rapid synthesis of nanochannel carbon materials, (4) nanoparticle supported on nanocarbon, and (5) heteroatom-containing carbon substances synthesized from monomers.

DOI： 10.2473/journalofmmij.132.47

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  

The conductivity of carbon nanoballs (CNBs) was enhanced by two orders of magnitude with the addition of carbon tetrachloride through a room temperature solution plasma process without post-heat treatment. The synthesized CNBs demonstrated the lowest resistivity of 8 Ω cm when the ratio of benzene to carbon tetrachloride was adjusted to 3:2. The morphologies from Transmission Electron Microscopy (TEM) showed the benzene-synthesized CNBs appeared as amorphous carbon while CNBs generated from the mixture of carbon tetrachloride and benzene were presented as short range graphite with turbostratic structure. From Raman spectroscopy and X-ray diffraction patterns, the results indicated the transition from amorphous carbon to nanocrystalline-graphite (NCG). From chemical elemental analysis, the hydrogen mole percentage decreased 20-50% when 20-60 vol% of carbon tetrachloride was added into benzene. We expect that this approach can be extended to enhance the conductivity of all kinds of amorphous carbonaceous materials in other synthesis technologies under room temperature.

DOI： 10.1039/c6ra02453j

Web of Science

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：RSC Advances  

Nitrogen-carbon nanosheets (NCNS), composed of multi-layer graphene with turbostratic stacking, were successfully synthesized through a solution plasma processing (SPP) at room temperature and an atmospheric pressure. The plasma was generated in 200 mL of N-methyl-2-pyrrolidone (NMP), which was applied as the carbon and nitrogen precursors. The NCNS presented an electrical resistivity of 0.065 Ω cm, which is comparable with that of N-doped carbon nanofibers (CNFs) and N-doped carbon nanotubes (CNTs). The synthesis rate of NCNS was 20 mg min-1. From the characteristics analyses, NCNS showed the surface area of 277 m2 g-1, a pore volume of 0.95 cm3 g-1 and a moderate nitrogen content of 1.3 at%. The synthesized NCNS also exhibited catalytic activity towards oxygen reduction reaction (ORR). This unique synthesis method can be applicable to synthesize multiple types of heteroatom-carbon nanosheets.

DOI： 10.1039/c5ra23659b

Web of Science

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：RSC Advances  

DOI： 10.1039/c5ra20416j

Web of Science

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：Science and Technology of Advanced Materials  

DOI： 10.1080/14686996.2016.1140305

Scopus

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

DOI： 10.1039/c6ra19311k

Scopus

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

DOI： 10.1039/C6RA24214F

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 表面技術協会  

For this study, we applied a specific type of plasma in liquid phase named "solution plasma process（SPP）" for high-speed synthesis of gold nanoparticles（AuNPs）using an ethanol-water mixture as a liquid medium. Sputtering was conducted for the AuNP production. By applying high voltage across a pair of gold electrodes（∅＝1.0 mm）immersed in the liquid medium, ions formed in the plasma collided with the gold electrode surface and caused sputtering of the gold atoms. Subsequently, these atoms formed AuNPs immediately before dispersal into the medium. We inferred that the medium properties greatly influenced the SPP system sputtering mechanism. Accordingly, the influence of the ethanol-water mixture composition on the formation mechanism was studied in addition to the yield of the synthesized AuNPs. Results indicate that composition of the ethanol-water mixtures strongly influenced the breakdown conditions for the plasma formation and that the largest current observed at the ethanol mole fraction was 0.089-0.14. It is particularly interesting that this composition of the ethanol-water mixture led to the highest AuNPs formation yield. Our findings suggest that high-speed synthesis of metal nanoparticles in the SPP system is achievable by altering the type and/or composition of the liquid medium.

DOI： 10.4139/sfj.67.46

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

DOI： 10.1039/c6ra19311k

Scopus

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

DOI： 10.1039/C6RA24214F

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 表面技術協会  

For this study, we applied a specific type of plasma in liquid phase named "solution plasma process（SPP）" for high-speed synthesis of gold nanoparticles（AuNPs）using an ethanol-water mixture as a liquid medium. Sputtering was conducted for the AuNP production. By applying high voltage across a pair of gold electrodes（∅＝1.0 mm）immersed in the liquid medium, ions formed in the plasma collided with the gold electrode surface and caused sputtering of the gold atoms. Subsequently, these atoms formed AuNPs immediately before dispersal into the medium. We inferred that the medium properties greatly influenced the SPP system sputtering mechanism. Accordingly, the influence of the ethanol-water mixture composition on the formation mechanism was studied in addition to the yield of the synthesized AuNPs. Results indicate that composition of the ethanol-water mixtures strongly influenced the breakdown conditions for the plasma formation and that the largest current observed at the ethanol mole fraction was 0.089-0.14. It is particularly interesting that this composition of the ethanol-water mixture led to the highest AuNPs formation yield. Our findings suggest that high-speed synthesis of metal nanoparticles in the SPP system is achievable by altering the type and/or composition of the liquid medium.

DOI： 10.4139/sfj.67.46

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Institute of Electrostatics Japan  

A special type of liquid plasma, named solution plasma (SP), has been applied to produce nanosized carbon black for the electrode material in Li-air battery. However, heat-treatment around 800 degree is essential to reduce the hydrogen atom remained within the carbon and to increase carbon's conductivity. In order to eliminate the energy-intensive heating process, in this study, we proposed to remove hydrogen atom by introducing chemical with halogen atom under room temperature plasma operation. Carbon nanoparticles were prepared by solution plasma with pure benzene (C6H6), chlorobenzene (C6H5Cl), various types of dichlorobenzene (C6H5Cl2) including 1,2-chlorobenzene, 1,3-chlorobenzene and 1,4 chlorobenzene served as the carbon precursors. The applied pulse frequency, applied voltage and pulse width were strictly controlled to be 25 kHz, 1 kV and 2 μs. The energy per pulse E and average energy per second Eavg by this specific plasma condition were calculated to be approximately 200 μJ and 5 J. The morphology of the synthesized carbon nanoball from benzene and 1,4-chlorobenzene were indicated in Fig. 1. The layer structure has been developed clearly on the outer layer of the carbon synthesized by chlorobenzene, as shown in Fig. 1(b). The resistivity of synthesized carbon by benzene was found to be 820 Ωcm, and decreased to 1.8 Ωcm when chlorobenzene was applied as precursor. From elemental analysis, the mole percentage of hydrogen remained in the synthesized carbon matrix decreased from 20% to 8.8% when the precursor changed from benzene to 1,4-chlorobenzene. We proposed that the chlorine atom in chlorobenzene reacted with hydrogen atoms and formed HCl (g), and successfully subtracted the hydrogen atom from the carbon matrix. Thus, sp2 bonding within carbon atoms was preferred and the conductivity of the synthesized carbon was easily enhanced.

DOI： 10.34343/ijpest.2016.10.02.146

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Institute of Electrostatics Japan  

This research reported an innovative method to synthesize inexpensive and bi-functional catalyst electrode material for the application in Li-air battery. Non-novel metal, Cu and Fe were served, respectively, as alternative Oxygen Reduction Reaction (ORR) and Oxygen Evolution Reaction (OER). Solution Plasma Process was applied to synthesized Cu-Fe metal nanoparticles and carbon nanoparticles simultaneously. SPP was generated in benzene 100 mL using a bipolar pulse power supply. Iron and copper of diameter 1.0 mm were used for the discharge electrode and precursor of the bimetallic nanoparticles. Solution was reacted and stirred continuously for 20 minutes. Based on the amount of electrode consumption and ICP-AES analysis, the percentage of Cu and Fe supported on carbon were respectively, 2.8 and 1.0 wt%. The diameter of metal nanoparticles was approximately 10 nm, where the carbon nanoparticles ranged between 20-30 nm. From XRD analyses, the presences of Cu, Fe and CuFe2O4 were confirmed. In the performance of cyclic voltammetry, Fe and Cu nanoparticles showed the catalytic activity, respectively, for ORR and OER, at -0.38 and above 0.5 V. In the case of Fe-Cu bimetallic nanoparticles, it showed the combined catalytic activities of the single particles.

DOI： 10.34343/ijpest.2016.10.01.051

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Colloids and Surfaces B: Biointerfaces  

DOI： 10.1016/j.colsurfb.2015.07.080

Web of Science

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 Physical Chemistry A  

Our previous research demonstrated that using ethanol-water mixture as a liquid medium for the synthesis of gold nanoparticles by the solution plasma process (SPP) could lead to an increment of the reaction rate of ∼35.2 times faster than that in pure water. This drastic change was observed when a small amount of ethanol, that is, at an ethanol mole fraction (χethanol) of 0.089, was added in the system. After this composition, the reaction rate decreased continuously. To better understand what happens in the ethanol-water mixture-based SPP, in this study, effect of the ethanol content on the radical formation in the system was verified. We focused on detecting the magnetic resonance of electronic spins using electron spin resonance spectroscopy to determine the type and quantity of the generated radicals at each χethanol. Results indicated that ethanol radicals were generated in the ethanol-water mixtures and exhibited maximum quantity at the xethanol of 0.089. Relationship between the ethanol radical yield and the rate of reaction, along with possible mechanism responsible for the observed phenomenon, is discussed in this paper.

DOI： 10.1021/acs.jpca.5b07224

Web of Science

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：Chemical Engineering Journal  

DOI： 10.1016/j.cej.2015.06.078

Web of Science

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：JOM  

DOI： 10.1007/s11837-015-1610-6

Web of Science

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：JOM  

Carbon nanomaterials were synthesized by using the solution plasma process and the carbon structure was precisely controlled through adjusting electrode gap distances. Transmission electron microscope and diffraction images showed ordered graphitic layers and clear ring patterns when the electrode distance was wider. The measurement of conductive properties has been improved approximately 400 times from 19 k Ω cm to 47 Ω cm, and the C/H ratio from the result of elemental analysis decreased from 0.31 to 0.18 with decreasing resistivity of carbon. These results showed that the electrode distance was an important factor to control the energy input during the synthesis of carbon materials in the plasma/gas zone generated by solution plasma processing and strongly affect the properties of synthesized carbon materials.

DOI： 10.1007/s11837-015-1660-9

Web of Science

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：Physical Review C - Nuclear Physics  

The PHENIX Collaboration has measured φ meson production in d+Au collisions at sNN=200 GeV using the dimuon and dielectron decay channels. The φ meson is measured in the forward (backward) d-going (Au-going) direction, 1.2y2.2 (-2.2y-1.2) in the transverse-momentum (pT) range from 1-7 GeV/c and at midrapidity y0.35 in the pT range below 7 GeV/c. The φ meson invariant yields and nuclear-modification factors as a function of pT, rapidity, and centrality are reported. An enhancement of φ meson production is observed in the Au-going direction, while suppression is seen in the d-going direction, and no modification is observed at midrapidity relative to the yield in p+p collisions scaled by the number of binary collisions. Similar behavior was previously observed for inclusive charged hadrons and open heavy flavor, indicating similar cold-nuclear-matter effects.

DOI： 10.1103/PhysRevC.92.044909

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：Electrochemistry Communications  

The synthesis of boron-doped carbon nanoparticles (BCNP) has been achieved through a solution plasma process without the addition of a metal catalyst source using a mixture of benzene and triphenyl borate as precursor. The electrocatalytic activity toward the oxygen reduction reaction (ORR) of BCNP can be improved in terms of onset potential and current density compared to that of undoped carbon nanoparticles in alkaline solution. Moreover, BCNP possesses superior long-term durability and tolerance to methanol oxidation in the ORR.

DOI： 10.1016/j.elecom.2015.07.005

Web of Science

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：Physical Review Letters  

We present the first measurement of elliptic (v2) and triangular (v3) flow in high-multiplicity He3+Au collisions at sNN=200GeV. Two-particle correlations, where the particles have a large separation in pseudorapidity, are compared in He3+Au and in p+p collisions and indicate that collective effects dominate the second and third Fourier components for the correlations observed in the He3+Au system. The collective behavior is quantified in terms of elliptic v2 and triangular v3 anisotropy coefficients measured with respect to their corresponding event planes. The v2 values are comparable to those previously measured in d+Au collisions at the same nucleon-nucleon center-of-mass energy. Comparisons with various theoretical predictions are made, including to models where the hot spots created by the impact of the three He3 nucleons on the Au nucleus expand hydrodynamically to generate the triangular flow. The agreement of these models with data may indicate the formation of low-viscosity quark-gluon plasma even in these small collision systems.

DOI： 10.1103/PhysRevLett.115.142301

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：Physical Review C - Nuclear Physics  

We have studied the dependence of azimuthal anisotropy v2 for inclusive and identified charged hadrons in Au+Au and Cu+Cu collisions on collision energy, species, and centrality. The values of v2 as a function of transverse momentum pT and centrality in Au+Au collisions at sNN=200 and 62.4 GeV are the same within uncertainties. However, in Cu+Cu collisions we observe a decrease in v2 values as the collision energy is reduced from 200 to 62.4 GeV. The decrease is larger in the more peripheral collisions. By examining both Au+Au and Cu+Cu collisions we find that v2 depends both on eccentricity and the number of participants, Npart. We observe that v2 divided by eccentricity () monotonically increases with Npart and scales as Npart1/3. The Cu+Cu data at 62.4 GeV falls below the other scaled v2 data. For identified hadrons, v2 divided by the number of constituent quarks nq is independent of hadron species as a function of transverse kinetic energy KET=mT-m between 0.1<KET/nq<1 GeV. Combining all of the above scaling and normalizations, we observe a near-universal scaling, with the exception of the Cu+Cu data at 62.4 GeV, of v2/(nq··Npart1/3) vs KET/nq for all measured particles.

DOI： 10.1103/PhysRevC.92.034913

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：Physical Review C - Nuclear Physics  

We present a systematic study of charged-pion and kaon interferometry in Au+Au collisions at sNN=200 GeV. The kaon mean source radii are found to be larger than pion radii in the outward and longitudinal directions for the same transverse mass; this difference increases for more central collisions. The azimuthal-angle dependence of the radii was measured with respect to the second-order event plane and similar oscillations of the source radii were found for pions and kaons. Hydrodynamic models qualitatively describe the similar oscillations of the mean source radii for pions and kaons, but they do not fully describe the transverse-mass dependence of the oscillations.

DOI： 10.1103/PhysRevC.92.034914

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Environmental Technology (United Kingdom)  

DOI： 10.1080/09593330.2014.1003981

Web of Science

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Environmental Technology (United Kingdom)  

DOI： 10.1080/09593330.2014.1003981

Web of Science

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：Physical Review Letters  

We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and minimum bias p+p collisions at sNN=200GeV. The charged hadron is measured at midrapidity |η|<0.35, and the energy is measured at large rapidity (-3.7<η<-3.1, Au-going direction). An enhanced near-side angular correlation across |Δη|>2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v2 for inclusive charged hadrons at midrapidity up to pT=4.5GeV/c. We also present the measurement of v2 for identified π± and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy-ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at sNN=5.02TeV. The magnitude of the mass ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.

DOI： 10.1103/PhysRevLett.114.192301

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Environmental Science and Technology  

DOI： 10.1007/s13762-014-0570-7

Web of Science

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Environmental Science and Technology  

DOI： 10.1007/s13762-014-0570-7

Web of Science

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：Physical Review C - Nuclear Physics  

The standard model (SM) of particle physics is spectacularly successful, yet the measured value of the muon anomalous magnetic moment (g-2)μ deviates from SM calculations by 3.6σ. Several theoretical models attribute this to the existence of a "dark photon," an additional U(1) gauge boson, which is weakly coupled to ordinary photons. The PHENIX experiment at the Relativistic Heavy Ion Collider has searched for a dark photon, U, in π0,η→γe+e- decays and obtained upper limits of O(2×10-6) on U-γ mixing at 90% C.L. for the mass range 30<mU<90 MeV/c2. Combined with other experimental limits, the remaining region in the U-γ mixing parameter space that can explain the (g-2)μ deviation from its SM value is nearly completely excluded at the 90% confidence level, with only a small region of 29<mU<32 MeV/c2 remaining.

DOI： 10.1103/PhysRevC.91.031901

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：Physical Review C - Nuclear Physics  

Measurements of bottomonium production in heavy-ion and p+p collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The inclusive yield of the three Υ states, Υ(1S+2S+3S), was measured in the PHENIX experiment via electron-positron decay pairs at midrapidity for Au+Au and p+p collisions at sNN=200 GeV. The Υ(1S+2S+3S)→e+e- differential cross section at midrapidity was found to be Beedσ/dy=108±38(stat)±15(syst)±11(luminosity) pb in p+p collisions. The nuclear modification factor in the 30% most central Au+Au collisions indicates a suppression of the total Υ state yield relative to the extrapolation from p+p collision data. The suppression is consistent with measurements made by STAR at RHIC and at higher energies by the CMS experiment at the Large Hadron Collider.

DOI： 10.1103/PhysRevC.91.024913

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 Alloys and Compounds  

Well-crystallized PdAu nanoparticles supported on Ketjen Black (KB) were successfully fabricated when both Pd and Au wires were served as the electrode pair by a solution plasma technique at atmospheric pressure. The synthesis of PdAu nanoparticles was almost simultaneous with their dispersion on KB. As-obtained PdAu nanoparticles were confirmed to be alloy by ultraviolet-visible spectrophotometer, transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDX) of each particle. PdAu nanoparticles with the average diameter of 2-5 nm were equably distributed on KB. PdAu nanoparticles showed good electrocatalytic activity both in acidic and alkaline solution corresponding to their obvious oxidation and reduction features. PdAu nanoparticles have improved electrochemical stability compared with the electrochemical properties of Pd and Au nanoparticles mixture after long time multi-scan cyclic voltammetry. Multi-scan cyclic voltammetry also presented the PdAu nanoparticles in alkaline solution have better stability than that in acidic solution. Thus as-obtained PdAu alloy nanoparticles would become a promising electrocatalysts for fuel cells or Li-air batteries. This novel process showed its potential applications in designing optimization of catalysts for fuel cells or Li-air batteries in future.

DOI： 10.1016/j.jallcom.2014.09.051

Web of Science

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：一般社団法人 表面技術協会  

DOI： 10.4139/sfj.66.70

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：一般社団法人 表面技術協会  

Many studies of recent decades have specifically examined high-performance carbon materials for application in next-generation batteries. Recently, an innovative technology named solution plasma (SP) has been drawing attention to carbon material synthesis. The most attractive aspect of SP is that, through this technology, the physical and chemical properties of synthesized carbon can be altered easily by varying the organic solvent. However, the conductivity of the SP synthesized carbon requires further improvement for application as an electrode material. In this study, molecules having π orbitals such as naphthalene or anthracene were introduced into benzene solvent to improve the conductivity of the synthesized carbon. Results of resistance measurements show that the resistance values of naphthalene (26.4 Ωcm) and anthracene (16.6 Ωcm) introduced carbons were improved by about 4 and 6 times, respectively, compared to carbon obtained from pure benzene (104 Ωcm). Details of the effects of solutes on the crystallinity and conductivity of the synthesized carbon are discussed.

DOI： 10.4139/sfj.66.416

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c4cp05995f

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：Physical Chemistry Chemical Physics  

An extraordinary high-speed synthesis of gold nanoparticles (AuNPs) was discovered by synthesizing the AuNPs in ethanol-water mixtures using a solution plasma process (SPP). The influence of the ethanol mole fraction (χethanol) in the ethanol-water mixtures on the reduction rate of gold chloride ions to AuNPs under the SPP system was studied. The results indicated that the reaction rate of the AuNPs synthesis exhibited a maximum value (i.e. 35.2 times faster than in a pure water system) at the significant point where the partial molar volumes of ethanol and water changed drastically.

DOI： 10.1039/c5cp05168a

Web of Science

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：Physical Chemistry Chemical Physics  

Black titania spheres (H-TiO<inf>2-x</inf>) were synthesized via a simple green method assisted by water plasma at a low temperature and atmospheric pressure. The in situ production of highly energetic hydroxyl and hydrogen species from water plasma are the prominent factors in the oxidation and hydrogenation reactions during the formation of H-TiO<inf>2-x</inf>, respectively. The visible-light photocatalytic activity toward the dye degradation of H-TiO<inf>2-x</inf> can be attributed to the synergistic effect of large-surface area, visible-light absorption and the existence of oxygen vacancies and Ti³⁺ sites.

DOI： 10.1039/c5cp00171d

Web of Science

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 Materials Chemistry A  

Fluorine-doped carbon nanoparticles (FCNPs) were synthesized via a simple one-step solution plasma process for the first time. This synthesis strategy can be achieved at relatively low temperature and atmospheric pressure without the involvement of a metal catalyst. A mixture of toluene (C<inf>6</inf>H<inf>5</inf>CH<inf>3</inf>) and trifluorotoluene (C<inf>6</inf>H<inf>5</inf>CF<inf>3</inf>) was used as a precursor for the synthesis. The fluorine doping content can be varied from 0.95 to 4.52 at%, depending on the precursor mixing ratio. The structural analyses reveal that FCNPs mainly exhibit a disordered amorphous structure. The incorporation of fluorine atoms results in the creation of more defect sites and disordered structure in the carbon particles. The electrocatalytic activity toward the oxygen reduction reaction (ORR) of FCNPs in an alkaline solution shows a significant improvement with increasing fluorine doping content, as reflected in an increased limiting current density and a positively shifted onset potential. In association with X-ray photoelectron spectroscopy (XPS) analysis, an improved ORR activity is possibly attributed to the intercalation of ionic C-F and semi-ionic C-F bonds in the carbon structure. In addition, FCNPs possess excellent long-term operation durability and strong tolerance to methanol oxidation compared to those of a commercial Pt-based catalyst. Our results from this study not only confirm the applicability of the solution plasma process to the synthesis of FCNPs with a controllable fluorine doping level but also provide detailed information of FCNPs as potential alternative ORR catalysts for the electrocatalysis research.

DOI： 10.1039/c5ta00244c

Web of Science

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c4cp05995f

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  

Herein, is reported a novel in situ one-step synthesis method of bimetallic nanoparticles (NPs) supported on carbon black, which can markedly prevent the aggregation and growth of NPs, resulting in a small particle size (average 5 nm), good dispersion, and high-electrocatalytic-activity. This journal is

DOI： 10.1039/c5ra04220h

Web of Science

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：RSC Advances  

DOI： 10.1039/c5ra03343h

Web of Science

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：Physical Chemistry Chemical Physics  

DOI： 10.1039/c4cp03868a

Web of Science

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 the Electrochemical Society  

DOI： 10.1149/2.0351514jes

Web of Science

Scopus

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

DOI： 10.1557/opl.2015.787

Scopus

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

DOI： 10.1557/opl.2015.13

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials Today: Proceedings  

DOI： 10.1016/j.matpr.2015.09.017

Scopus

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

DOI： 10.1557/opl.2015.787

Scopus

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

DOI： 10.1557/opl.2015.13

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials Today: Proceedings  

DOI： 10.1016/j.matpr.2015.09.017

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Nuclear Physics A  

DOI： 10.1016/S0375-9474(14)00604-6

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：Nuclear Physics A  

DOI： 10.1016/S0375-9474(14)00604-6

Scopus

記述言語：日本語   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）   出版者・発行元：Journal of Nanoscience and Nanotechnology  

We discussed the electron impact dissociation behavior of the organosilicon molecules with methyl groups, based on the fragment pattern and molecular-orbital calculation of the bond dissociation energies for the molecules. From the calculation of bond dissociation energy of the organosilicon molecules, methyl groups, which bonded directly to the silicon atom, were found to have the weakest. Regarding the fragment patterns of the reactants investigated by a quadrupole mass spectrometer, the hexamethyldisiloxane was harder to dissociate than the trimethylmethoxysilane due to the strong Si-O bonding force, which also affected the dissociation in the plasma. From the above considerations, dissociation reactions by electron impact could be partly identified.

DOI： 10.1166/jnn.2014.10175

Web of Science

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：Progress in Natural Science: Materials International  

DOI： 10.1016/j.pnsc.2014.10.011

Web of Science

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：Physical Review C - Nuclear Physics  

The PHENIX experiment at the Relativistic Heavy Ion Collider has performed a systematic study of KS0 and K∗0 meson production at midrapidity in p+p,d+Au, and Cu+Cu collisions at sNN=200 GeV. The KS0 and K∗0 mesons are reconstructed via their KS0→π0(→γγ)π0(→γγ) and K∗0→K±π decay modes, respectively. The measured transverse-momentum spectra are used to determine the nuclear modification factor of KS0 and K∗0 mesons in d+Au and Cu+Cu collisions at different centralities. In the d+Au collisions, the nuclear modification factor of KS0 and K∗0 mesons is almost constant as a function of transverse momentum and is consistent with unity, showing that cold-nuclear-matter effects do not play a significant role in the measured kinematic range. In Cu+Cu collisions, within the uncertainties no nuclear modification is registered in peripheral collisions. In central collisions, both mesons show suppression relative to the expectations from the p+p yield scaled by the number of binary nucleon-nucleon collisions in the Cu+Cu system. In the pT range 2-5 GeV/c, the strange mesons (KS0,K∗0) similarly to the φ meson with hidden strangeness, show an intermediate suppression between the more suppressed light quark mesons (π0) and the nonsuppressed baryons (p,p¯). At higher transverse momentum, pT>5 GeV/c, production of all particles is similarly suppressed by a factor of ≈2.

DOI： 10.1103/PhysRevC.90.054905

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：Vacuum  

DOI： 10.1016/j.vacuum.2014.07.007

Web of Science

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 the Taiwan Institute of Chemical Engineers  

DOI： 10.1016/j.jtice.2014.09.001

Web of Science

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 Power Sources  

DOI： 10.1016/j.jpowsour.2014.03.072

Web of Science

Scopus

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： 10.1007/s11090-014-9546-0

Web of Science

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）  

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：Applied Surface Science  

DOI： 10.1016/j.apsusc.2014.04.186

Web of Science

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：Applied Physics Letters  

DOI： 10.1063/1.4892827

Web of Science

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.4887806

Web of Science

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）  

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）  

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）  

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）  

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：WILEY-BLACKWELL  

The SrTiO3 (STO) thin films were directly grown on Si(111) substrates without buffer layer by an electron-cyclotron-resonance ion beam sputter deposition. The growth temperature was varied from 700 degrees C to 850 degrees C, while other parameters were kept unchanged. X-ray structural analysis demonstrates that the growth temperature has a strong influence in tuning degree of (100) orientation. The STO film grown at 800 degrees C is found to be the highest degree of (100) orientation (98%) and a strong (100) fiber texture. For the surface morphology, the development of plate-shaped grains reveals a good correlation with the change in the degree of (100) orientation. Moreover, the leakage current-voltage characteristics of the Au/STO/Si(111) metal-insulator-semiconductor capacitors are investigated and discussed in considerable detail.

DOI： 10.1111/jace.12912

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：一般社団法人電子情報通信学会  

太陽光パネル生産量が年間40GWを超えるようになり、太陽光発電技術は主要な電力源となっている。天気の揺らぎが不可避であるため、近い将来再生可能エネルギーの大規模な利用は過剰な電力を生産する問題に直面すると思われる。人工光合成の分野で研究される太陽光の化学エネルギーへの直接変換よりもむしろ、余剰電力を利用し二酸化炭素を安全でエネルギー密度が高く、貯蔵が容易な化学エネルギーに還元できれば理想である。

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：Applied Physics Letters  

DOI： 10.1063/1.4870525

Web of Science

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（学術雑誌）  

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：Applied Physics Letters  

DOI： 10.1063/1.4868872

Web of Science

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（学術雑誌）  

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）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.carbpol.2013.11.025

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）  

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）  

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  

記述言語：日本語   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）  

掲載種別：研究論文（学術雑誌）   出版者・発行元：Biomimetic Architectures by Plasma Processing: Fabrication and Applications  

Scopus

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.4887806

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：ROYAL SOC CHEMISTRY  

We report a novel strategy to produce stable colloidal gold nanoparticles (AuNPs) in alginate aqueous solution which can be done in one step and without any chemicals. The AuNPs were produced by applying a voltage across a pair of gold electrodes which were immersed in alginate aqueous solution. Since the generation of AuNPs was caused by the sputtering of gold electrodes, the process was named the solution plasma sputtering (SPS) process. We utilize the alginate polymer in order to meet three important requirements: (1) to promote the generation of plasma in a liquid environment, (2) to endow biocompatibility to the AuNPs, and (3) to provide colloidal stability to the AuNPs-alginate aqueous suspensions. The alginate concentrations were varied as 0.2, 0.5, and 0.9 %w/v. The concentration-dependent effect on the particle size of AuNPs, the physical absorption property and the stability of the AuNPs-alginate suspensions were studied. Results indicate that preparation of chemical-free colloidal AuNPs-alginate aqueous suspension is successful by the SPS process. The obtained colloidal suspensions were stable and able to retain their strong plasmon absorption bands within a reasonable time period. As a consequence, this is a high-potential technique to produce AuNPs suspended in alginate aqueous solution appropriate for biomedical applications.

DOI： 10.1039/c3ra45029e

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：Physical Chemistry Chemical Physics  

DOI： 10.1039/c4cp01406e

Web of Science

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：RSC Advances  

DOI： 10.1039/c4ra02380c

Web of Science

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：ROYAL SOC CHEMISTRY  

Graphene flakes were successfully produced by a simple method named a solution plasma process. The plasma was generated between two carbon electrode tips which were immersed in distilled water. The production approach is a continuous energy accumulation induced by focusing of plasma streamers on the surface of electrodes. This focused energy produces thermal gradient zones where a proper energy level is produced. Concisely, the energy is enough to extract graphene layers from the graphite structure but not enough to break covalent C-C bonds within the graphene sheets. Optical emission spectroscopy results showed the decomposition of carbon from the graphite electrodes with different intensities for the carbon species. Transmission electron microscopy images confirmed the hexagonal honeycomb structure of the graphene flakes. Furthermore, broadening of the 2D band in the Raman spectra revealed that the graphene flakes were disordered multilayers.

DOI： 10.1039/c4ra03253e

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  

We report the in situ synthesis of nitrogen-doped carbon nanoparticles (NCNPs) by a solution plasma process without the addition of metal catalysts. Organic liquid mixtures of benzene and pyrazine were used as the precursors for the synthesis. The nitrogen-doping content can be easily controlled by changing the amount of pyrazine in the precursor. The NCNPs synthesized from the solution plasma process exhibit a turbostratic structure with highly uniform nanoscale particles. The nitrogen atoms can be homogeneously incorporated into the entire carbon structure due to the in situ doping during the growth and formation of the carbon particles. The electrochemical activity toward the oxygen reduction reaction (ORR) of the NCNPs in an alkaline medium reveals the improvement in terms of both the onset potential and current density as the nitrogen-doping content increases. The enhanced ORR activity of the NCNPS is mainly attributed to the presence of pyridinic-N and graphitic-N bonding configurations. They also possess long-term durability and excellent tolerance to methanol crossover effects. The results obtained in this study have demonstrated that the solution plasma process has great potential for the synthesis of metal-free nitrogen-doped carbon electrocatalysts for the ORR. We expect that this approach can be extended to the synthesis of other heteroatom-doped carbonaceous materials for a broad range of research applications in energy conversion and storage.

DOI： 10.1039/c4ta03010a

Scopus

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

DOI： 10.1557/opl.2014.319

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 応用物理学会  

DOI： 10.11470/oubutsu.83.6_486

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

DOI： 10.1557/opl.2014.319

Scopus

掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 応用物理学会  

DOI： 10.11470/oubutsu.83.6_486

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/jp409368c

Web of Science

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（学術雑誌）  

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）  

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）  

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）  

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）  

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）  

掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.polymdegradstab.2013.07.001

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/ppap.201200148

Web of Science

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）  

掲載種別：研究論文（学術雑誌）  

DOI： 10.1111/jne.12076

Web of Science

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）  

DOI： 10.1111/jne.12076

Web of Science

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）  

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）  

DOI： 10.1016/j.carbon.2013.04.040

Web of Science

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）  

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）  

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）  

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）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jallcom.2013.02.033

Web of Science

掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.polymdegradstab.2013.01.011

Web of Science

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）  

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）  

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）  

DOI： 10.1007/s00418-013-1083-z

Web of Science

掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00418-013-1083-z

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.jallcom.2012.08.033

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：一般社団法人 表面技術協会  

Solution plasma processing, a reaction field available for chemical engineering, has high chemical activity because of its high electron temperature in the liquid, but low gas temperature. Consequently, it supplies activated species from plasma to liquid phases. Therefore, solution plasma has been anticipated for application to chemical processes such as synthesis of metal nanoparticles, and as a water treatment for sterilization and waste. We sought to synthesize silica by solution plasma, and to examine the effects of pH in the solution on the morphology and the chemical bonding state. Aqueous solutions containing tetraethoxysilane (TEOS) and ethanol were used as starting solutions. Then HCl or DEA (2.2'-iminodiethanol) was added to the solution to adjust the pH. The obtained materials were evaluated using scanning electron spectroscopy (SEM) and nuclear magnetic resonance (NMR). The morphology changes were observed as a two-dimensional tabular structure in an acid state, three-dimensional spherical structure in a base state, and two-dimensional and three-dimensional mixed structures in a neutral state. These structures originate mainly from the chemical bonding state of Si(OR)₃(OSi), Si(OR)₂(OSi)₂ in an acid state, Si(OR)₁(OSi)₃, Si(OSi)₄ in a base state, and Si(OR)₂(OSi)₂ and Si(OR)(OSi)₃ in a neutral state.

DOI： 10.4139/sfj.64.180

掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.vacuum.2012.08.011

Web of Science

掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s11665-012-0320-2

Web of Science

掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ssc.2012.12.026

Web of Science

Scopus

その他リンク： http://orcid.org/0000-0001-8757-3933

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）  

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）  

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）  

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）  

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）  

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）  

DOI： 10.1088/0957-4484/24/5/055604

Web of Science

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）  

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）   出版者・発行元：静電気学会  

掲載種別：研究論文（学術雑誌）   出版者・発行元：静電気学会  

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）  

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）  

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）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.7567/JJAP.52.01AN05

Web of Science

掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c3nr01229h

Web of Science

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）  

DOI： 10.2166/wst.2013.321

Web of Science

掲載種別：研究論文（学術雑誌）  

DOI： 10.7567/jjap.52.126202

掲載種別：研究論文（学術雑誌）  

掲載種別：研究論文（学術雑誌）  

DOI： 10.7567/jjap.52.125101

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）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.4820780

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.4820780

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.7567/JJAP.52.126202

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.7567/JJAP.52.125101

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）   出版者・発行元：フォトポリマー学会  

Three-dimensionally integrated micro solution plasmas were generated in gas bubbles in porous dielectric materials filled with gas/liquid mixed medium. The methylene blue molecules in aqueous solution were decomposed by the treatment with the three-dimensionally integrated micro solution plasmas. Decomposition efficiency was 16 times higher than conventional solution plasma in the case of applied voltage of 5 kV. With decreasing applied voltage from 5 to 2 kV, the decomposition efficiency was improved up to 360% in comparison to that of 5 kV, while reduction in the decomposition rate was 40%.

DOI： 10.2494/photopolymer.26.507

記述言語：英語   掲載種別：研究論文（学術雑誌）  

その他リンク： http://orcid.org/0000-0001-8757-3933

記述言語：英語   掲載種別：研究論文（学術雑誌）