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

The effective utilization of plastic waste, including its use as an energy or chemical resource, has attracted much attention. Nevertheless, energy recovery from plastics via incineration generates air pollutants and toxic compounds, while chemical conversion requires significant energy inputs, especially in the case of gasification. Herein, we report the electrochemical conversion of plastics into electricity or hydrogen without the use of special procedures. When a mixture of plastic solid combined with an acidic solution was fed into an electrochemical cell, the solid was found to dissolve in the solution at 100 °C or higher, followed by the release of protons from the anode to the cathode according to a multi-electron oxidation reaction. This oxidation reaction required an anode that was sufficiently porous so as to allow transport of the reactants. Taking the sponge sample as an example, the dissolved polyurethane had a molecular weight of 2000 or higher, the transport of which was facilitated using a carbon support with a pore diameter of approximately 10 nm. In addition, carbon black having an ordered porous structure exhibited better reagent transport compared to a disordered porous carbon black with similar pore diameters. As a consequence, this cell continuously provided power densities on the order of mW cm−2 in the fuel cell mode and generated hydrogen at a low cell voltage of 0.55 V in the electrolyzer mode, using plastics as fuels at an operational temperature of 200 °C.

DOI： 10.1016/j.wasman.2019.10.019

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

Biomass raw materials, including agricultural residues, collected weeds, and wood chips, are important feedstocks for hydrogen production. Numerous attempts have been made to electrolyze biomass directly or indirectly to hydrogen because these processes allow for the production of hydrogen with less power consumption than water electrolysis. However, expensive metal-based electrocatalysts are needed, especially for the cathode reaction, in the electrolysis cells. Results from the present study demonstrate the production of hydrogen directly from cellulose, using an optimal mesoporous carbon as the cathode in addition to a partially oxygenated carbon anode at a temperature of 150 °C, with an electrolysis onset voltage of ca. 0.2 V, a current density of 0.29 A cm–2 at an electrolysis voltage of 1 V, and a current efficiency of approximately 100% for hydrogen production. These characteristics were comparable to those recorded when using a Pt/C anode and cathode under the same conditions. The sp2 planes of the carbon allowed π electrons to be donated to protons at the cathode. In addition, the mesoporous structure provided a sufficient amount of sp2 planes on the surface of the cathode.

DOI： 10.3390/catal10010106

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

This work aims to assess ionic conduction in anhydrous cement particles and hydrated cement pastes with aging periods of 5-25 days. When a cement sample was humidified (relative humidity = 100%) over the range of 50-100 0C, it exhibited bulk conductivities of 10-3-10-2 S cm-1, regardless of the hydration level, whereas the interfacial conductivities varied in the range of 10-7-10-3 S cm-1, depending on the structural defects or conduction pathways of the sample. Both the bulk and interfacial conductivities were increased to 0.01 S cm-1 or higher at 100 0C, although the sample required previous moistening with water mist. The major charge carrier in the sample was determined to be hydroxide ions, and the total ion transport number was approximately 1. Exposing the sample to a mixture of carbon dioxide and water vapor caused a decrease in the bulk and interfacial conductivities; however, the bulk conductivity was returned to the initial value by treatment with an acid.

DOI： 10.3390/ma12223701

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

<jats:sec><jats:title>PURPOSE</jats:title><jats:p> S-1 is a standard postoperative adjuvant chemotherapy for patients with stage II or III gastric cancer in Asia. Neoadjuvant or perioperative strategies dominate in Western countries, and docetaxel has recently shown significant survival benefits when combined with other standard regimens in advanced cancer and perioperative settings. </jats:p></jats:sec><jats:sec><jats:title>PATIENTS AND METHODS</jats:title><jats:p> This randomized phase III study was designed to prove the superiority of postoperative S-1 plus docetaxel over S-1 alone for R0 resection of pathologic stage III gastric cancer. The sample size of 1,100 patients was necessary to detect a 7% increase in 3-year relapse-free survival as the primary end point (hazard ratio, 0.78; 2-sided α = .05; β = .2). </jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p> The second interim analysis was conducted when the number of events reached 216 among 915 enrolled patients (median follow-up, 12.5 months). Analysis demonstrated the superiority of S-1 plus docetaxel (66%) to S-1 (50%) for 3-year relapse-free survival (hazard ratio, 0.632; 99.99% CI, 0.400 to 0.998; stratified log-rank test, P < .001), and enrollment was terminated as recommended by the independent data and safety monitoring committee. Incidences of grade 3 or greater adverse events, particularly neutropenia and leukopenia, were higher in the S-1 plus docetaxel group, but all events were manageable. </jats:p></jats:sec><jats:sec><jats:title>CONCLUSION</jats:title><jats:p> Addition of docetaxel to S-1 is effective with few safety concerns in patients with stage III gastric cancer. The present findings may also be applicable in countries in which perioperative adjuvant chemotherapy or chemoradiation is not standard. </jats:p></jats:sec>

DOI： 10.1200/jco.18.01138

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

Considerable amounts of hydrogen are produced from fossil fuels. In recent years, natural gas and biogas have received attention as important feedstocks for hydrogen production, because methane, their main component, is hydrogen rich and readily available. Methane steam reforming is the major industrial route for hydrogen production, but requires high temperature due to endothermic nature of the reaction. This report presents a new green technology for the efficient and ecological production of hydrogen from methane. A humidified methane was electrolyzed to hydrogen and carbon dioxide at low onset cell voltages (ca. 0.3–0.4 V), depending on the temperature (150–250 °C). Almost all currents were used for the production of hydrogen and carbon dioxide. Hydroxyl radicals generated from water vapor during the electrolysis played an important role as an active oxygen for the methane oxidation reaction at the anode. This is the first report on the production of hydrogen from methane at both low temperatures and voltages.

DOI： 10.1016/j.ijhydene.2018.12.044

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

Biohydrogen produced from the electrolysis of biomass is promising because the onset voltages are less than 1.0 V and comparable to those of water and alcohol-water electrolysis. The present study focuses on Miscanthus sinensis as a model grass because of its abundance and ease of cultivation in Japan. The electrochemical performance and hydrogen formation properties of electrolysis cells using grass as a biohydrogen source were evaluated at intermediate temperature to achieve electrolysis. The components, such as holocellulose, cellulose, lignin, and extractives, were separated from Miscanthus sinensis to understand the reactions of Miscanthus sinensis in the electrolysis cell. The relatively high resistivity and low current-voltage performance of an electrolysis cell using lignin were responsible for degradation of the electrolysis properties compared to those with pure cellulose or holocellulose as biohydrogen resources. Biohydrogen was formed according to Faraday’s law and evolved continuously at 0.1 A cm−2 for 3,000 seconds.

DOI： 10.1038/s41598-018-34544-y

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

Biomass electrolysis enables hydrogen (H2) production at onset voltages of less than 1 V, depending on the fuel species. However, biofuel derived from biomass not categorized as food and produced from environmentally friendly processes is needed for the development of sustainable strategies. In addition, the biofuel should not require special and expensive procedures for processing. The present report describes the direct electrolysis of waste newspaper for H2 production. Cellulose and lignin included in the newspaper were subject to dissolution and hydrolysis in a phosphoric acid solvent at the anode in a temperature range of 100–175 °C. The resulting decomposition products were electrolyzed to H2 and carbon dioxide (CO2), at low onset voltages (ca. 0.2 V) and high current efficiencies (H2: 1.0, CO2: 0.9). Carbon black functionalized with carbonyl groups showed greater catalytic activity than a Pt/C catalyst for the anode reaction. H2 yield reached ca. 0.2 g per 1 g of newspaper in a batch cell. H2 was produced continuously in a current-density range of 0.15–0.25 A cm−2 while maintaining plateau-like voltage behavior in a flow cell. The energy consumed for electrolysis at a current density of 0.15 A cm−2 was as low as 1.27 kWh (Nm3)−1.

DOI： 10.1016/j.apcatb.2018.03.021

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

Biomass has been considered as an alternative feedstock for energy and material supply. However, the lack of high-efficiency and low-cost processes for biomass utilization and conversion hinders its large-scale application. This report describes electrochemical hydrogen production from waste biomass that does not require large amounts of energy or high production costs. Hydrogen was produced by the electrolysis of bread residue, cypress sawdust, and rice chaff at an onset cell voltage of ca. 0.3 V, with high current efficiencies of approximately 100% for hydrogen production at the cathode and approximately 90% for carbon dioxide production at the anode. The hydrogen yields per 1 mg of the raw material were 0.1-0.2 mg for all tested fuels. Electrolysis proceeded continuously at plateau voltages that were proportional to the current. These characteristics were attributable to the high catalytic activity of the carbonyl-group functionalized mesoporous carbon for the anode reaction, and that the major components of biomass such as cellulose, starch, lignin, protein, and lipid were effectively utilized as fuels for hydrogen production.

DOI： 10.1021/acssuschemeng.8b01701

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

Hydrogen is produced conventionally by electrolyzing water or water vapor at onset voltages greater than 1 V, providing motivation for the development of more efficient electrolysis processes for a hydrogen economy. Numerous attempts have been made to use ethanol as a fuel for hydrogen production because this process reduces the electrolysis onset voltage significantly. However, ethanol feedstock from lignocellulose requires greater amounts of energy and results in higher production costs compared to those using starch as the feedstock. The current study describes direct lignin electrolysis at an onset voltage of ca. 0.25 V, with high current efficiencies of approximately 100 % for hydrogen production at the cathode and approximately 85 % for carbon dioxide production at the anode. Addition of H3PO4-impregnated lignin to the anode of a PtFe/C|Sn0.9In0.1P2O7 (150 μm)|Pt/C cell enabled hydrogen production at a temperature of 150 °C.

DOI： 10.1002/celc.201700917

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

The catalytic activity of the Pt/C anode in a fuel cell was improved by alloying Pt with other metals, followed by optimization of the alloy in terms of its atomic raio and content. The resulting PtFe/C anode yielded higher power densities and energy densities at 250°C for fuels composed of cypress, tissue paper, and cotton compared to those obtained using the Pt/C anode, despite its smaller Pt loading. The resulting fuel cell successfully produced energy using different fuel materials. The addition effect of Fe on the anode reaction was discussed based on the characterization kinetics.

DOI： 10.1246/bcsj.20170163

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1504/IJCISTUDIES.2016.10004364

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1504/IJDSS.2016.10000521

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  

Biomass is of significant interest in the field of advanced energy engineering, including the use of woody biomass as an energy source. However, because cellulose—the major component of wood—is insoluble in most solvents, an excessive amount of energy and special procedures are required to convert woody materials into liquid and gaseous fuel. This report describes a biomass fuel cell that provides power densities on the order of 10 mW cm−2 by direct utilization of wood sawdust and pulp as fuel. The fuel cell is simple, with H3PO4-impregnated raw materials located at the anode, and is operated at temperatures between 75 and 250°C. Cellulose or its decomposition products reacted with H2O to form CO2, where the coulombic yield was approximately 95% at 150°C or higher. Notably, the cell performance was superior to that of fuel cells with fuels (partially oxidized or dehydrated mono-to tetrasaccharides) obtained by an external treatment of cellulose with H3PO4.

DOI： 10.1149/2.0511706jes

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

The formation of highly oxidative and reductive states within and around WO3 and In2O3 during detection of NOx (NO and NO2) was investigated by attaching the metal oxide electrode to a proton-conducting Sn0.9In0.1P2O7 electrolyte, followed by electrode polarization at 200°C. Proton insertion and release occurred at the WO3 electrode, while metal-ion redox reactions proceeded at the In2O3 electrode. Although the hydrogen tungsten bronze formed under cathodic polarization was insensitive to NO and NO2, the WO3 operating under anodic polarization possessed sensitivity toward NO and NO2. Addition of these gases increased the ohmic, charge-transfer, and gas-diffusion resistances in a similar manner. The In2O3 underwent significant changes in NOx sensing ability upon changes in polarity and magnitude of the applied voltage. In particular, under cathodic polarization, the sensor resistance decreased upon addition of NO and NO2 in the range of -0.5 to -1.5 V, but increased upon addition at -2.0 V, due to reduction of In3+ to lower valence states, which selectively absorbed NO2 beginning at -1.7 V. The WO3 and In2O3 sensing abilities were not significantly affected by interference from O2, H2, CO, or n-C4H10, and the sensors became more sensitive toward NO2 as the WO3 and In2O3 particle size decreased.

DOI： 10.1149/2.0361709jes

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)  

Grammatical evolution (GE) is one of the evolutionary computations, which evolves genotype to map phenotype by using the Backus-Naur Form (BNF) syntax. GE has been widely employed to represent syntactic structure of a function or a program in order to satisfy the design objective. As the GE decoding process parses the genotype chromosome into array or list structures with left-order traversal, encoding process could change gene codons or orders after genetic operations. For improving this issue, this paper proposes a novel GE algorithm using tree representation learning (GETRL) and presents three contributions to the original GE, genetic algorithm (GA) and genetic programming (GP). Firstly, GETRL uses a tree-based structure to represent the functions and programs for practical problems. To be different from the traditional GA, GETRL adopts a genotype-to-phenotype encoding process, which transforms the genes structures for tree traversal. Secondly, a pointer allocation mechanism is introduced in this method, which allows the GETRL to pursue the genetic operations like typical GAs. To compare with the typical GP, however GETRL still generates a tree structure, our method adopts a phenotype-to-genotype decoding process, which allows the genetic operations be able to be apply into tree-based structure. Thirdly, due to each codon in GE has different expression meaning, genetic operations are quite different from GAs, in which all codons have the same meaning. In this study, we also suggest a multi-chromosome system and apply it into GETRL, which can prevent from overriding the codons for different objectives.

DOI： 10.1007/978-3-319-70093-9_36

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

Symbolic regression problems can be solved using grammatical evolution (GE), an evolutionary computation (EC) method, to find a function that coincides satisfactorily with the given datasets. The evolutional approach of GE is based on the grammar learning paradigm, which can translate the genotype (binary digit) into the phenotype (terminals and non-terminals). Unlike traditional codons in a genotype, the fittest codons in phenotype represented by the Backus-Naur form (BNF) are difficult for next generation genes to inherit the traits of parents, accounting for crossover and mutation. For this issue, this article presents a proposal of an advanced improvement to GE using a two-dimensional gene (GE2DG). In contrast to multi-chromosomal GE (GEMC), our proposal not only encloses the two-dimensional gene-expression for symbolic regression, but also introduces one independent gene defined as a conditional statement to express a new BNF grammar of an if-then (-else) branch. In the experiments described herein, continuous/discontinuous non-branch functions and continuous/discontinuous branch functions, four testing patterns, are considered as numerical examples. Results show that GE2DG has better performance than the original GE or GEMC. Especially for the case of branch functions, GE with hybrid chromosome (GEHC), where GE2DG is incorporated with GEMC, has faster convergence in symbolic regression than other methods.

DOI： 10.1504/IJCIS.2017.083634

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

In recent years, exhaust sensors have become increasingly attractive for use in energy and environmental technologies. Important issues regarding practical applications of these sensors, especially for soot measurements, include the further development of ion-conductive electrolytes and active electrode catalysts for meeting performance and durability requirements. Herein, we design a proton conductor with a high breakdown voltage and a sensing electrode with high sensitivity to electrochemical carbon oxidation, enabling continuous soot monitoring with self-regeneration of the sensor. A Si0.97 Al0.03 Hx P2 O7 layer with an excellent balance between proton conductivity and voltage endurance was grown on the surface of a Si0.97 Al0.03 O2 substrate by reacting it with liquid H3 PO4 at 600 °C. Specific reactivity of the electrochemically formed active oxygen toward soot was accomplished by adding a Pt-impregnated Sn0.9 In0.1Hx P2 O7 catalyst into a Pt sensing electrode. To make the best use of these optimized materials, a unipolar electrochemical device was fabricated by configuring the sensing and counter electrodes on the same surface of the electrolyte layer. The resulting amperometric mode sensor successfully produced a current signal that corresponded to the quantity of soot.

DOI： 10.1038/srep37463

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

Numerous studies have examined the switching properties of semi-or ion-conductors and isolators; however, most of these have focused on the ohmic resistance characteristics. Here, we report a new type of polarity-dependent switching phenomenon obtained for electrical devices with the configuration: metal working electrode |Si0.97Al0.03H0.03P2O7-polytetrafluoroethylene composite electrolyte |Pt/C counter electrode. The counter electrode is reversibly active for the water vapor oxidation and evolution reactions. The composite electrolyte exhibits high withstanding voltage capability in the bias voltage range of ± 7 V. When titanium was employed as the working electrode, the anodic polarization resistance was approximately two orders of magnitude greater than the cathodic polarization resistance. The ohmic resistance of the device was almost unchanged, regardless of the bias voltage polarity. Moreover, kinetically induced high-resistance/low-resistance states could be cyclically switched through positive/negative bias voltage pulses, and these states were also confirmed to be memorized at open circuit.

DOI： 10.1038/srep31691

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

SnSO4 was employed as an anode-active material for rechargeable batteries, where Sn4+ and Sn2+ ions are reduced to Sn2+ and Sn, respectively during charge while the inverse reactions occur during discharge. Undesired hydrogen production was substantially avoided by adjusting the charge voltage to 1.5V. The resulting cell functioned as a battery with an electrical capacity of 258mA hg-1 at 10mA cm-2 and as a fuel cell with power densities of 55-125 mW cm-2 at 0.8V.

DOI： 10.1246/cl.151015

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

Rechargeable proton-exchange membrane batteries that employ organic chemical hydrides as hydrogen-storage media have the potential to serve as next-generation power sources; however, significant challenges remain regarding the improvement of the reversible hydrogen-storage capacity. Here, we address this challenge through the use of metal-ion redox couples as energy carriers for battery operation. Carbon, with a suitable degree of crystallinity and surface oxygenation, was used as an effective anode material for the metal redox reactions. A Sn0.9In0.1P2O7-based electrolyte membrane allowed no crossover of vanadium ions through the membrane. The V4+/V3+, V3+/V2+, and Sn4+/Sn2+ redox reactions took place at a more positive potential than that for hydrogen reduction, so that undesired hydrogen production could be avoided. The resulting electrical capacity reached 306 and 258mAhg-1 for VOSO4 and SnSO4, respectively, and remained at 76 and 91% of their respective initial values after 50 cycles.

DOI： 10.1002/celc.201500473

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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：Journal of the Electrochemical Society  

There have been many attempts to develop solid-state sensor devices for detecting particulate matter (PM) in diesel exhaust; however, in most of these, the accumulated PM must be burned intermittently to allow subsequent sensing cycles. Here, we report a self-regenerable PM sensor using a proton conductive solid electrolyte and an active working electrode for PM oxidation. The withstanding voltage capability of BaZr0.8Y0.2O3-δ was greatly improved by the growth of a dense Zr1-xYxP2O7 film on the electrolyte surface. The reaction of PM with active oxygen under anodic polarization was further enhanced by the addition of IrO2 to the working electrode. As a result of these combined modifications, when the working electrode was anodically polarized, PM was oxidized to CO2 according to a four-electron reaction (C + 2H2O → CO2 + 4H+ + 4e-) while remaining below the self-ignition temperature. This amperometric sensor successfully produced a current signal corresponding to the quantity of PM in a gas stream at an operating temperature of 300°C. These results demonstrate that the sensor can carry out continuous monitoring of PM concentrations while self-regenerating.

DOI： 10.1149/2.1281614jes

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

Electrochemical devices integrating a fuel cell with a hydrogen storage medium are able to function as secondary batteries. Batteries incorporating a partially oxygenated carbon anode with a RuO2/C cathode exhibit excellent reversibility, but their performance is not yet sufficient for secondary battery applications. This is due to excessive oxygenation of the anode, degradation of the cathode and the excess weight of the electrolyte membrane. In the present work, we addressed these challenges through various improvements in the design of a rechargeable proton-exchange membrane battery. These included coating the surface of a significantly oxygenated carbon anode (O/C atomic ratio 0.131) with carbon black nanoparticles, nanocrystallization of a carbon-free RuO2 cathode (avg. crystallite size 1.1 nm) and the synthesis of an inorganic-organic composite electrolyte membrane. As a result of these optimizations, coulombic efficiencies of over 95% were achieved during charge/discharge over the voltage range of 0.0–1.5 V at 75°C. The resulting device exhibited an initial capacity of 330 mAh g−1 and was stable over 300 cycles, with maximum energy and power densities of 47 Wh kg−1 and 1114 W kg−1, respectively.

DOI： 10.1149/2.1341607jes

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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担当区分：筆頭著者   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：Chemistry Letters  

Direct utilization of urine in fuel cells is a promising technology for conversion into electricity. Here, we report the design of anode materials for high-temperature direct urine fuel cells and the performance of a fuel cell with an optimized anode at 300 °C. The resultant peak power densities reached 16.7mW cm-2 for urine and 26.5mW cm-2 for urea.

DOI： 10.1246/cl.141067

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

Expanding the range of supercapacitor operation to temperatures above 100°C is important because this would enable capacitors to operate under the severe conditions required for next-generation energy storage devices. In this study, we address this challenge by the fabrication of a solid-state supercapacitor with a proton-conducting Sn 0.95 Al0.05H0.05P2O7 (SAPO)-polytetrafluoroethylene (PTFE) composite electrolyte and a highly condensed H3 PO4 electrode ionomer. At a temperature of 200°C, the SAPO-PTFE electrolyte exhibits a high proton conductivity of 0.02 S cm-1 and a wide withstanding voltage range of ±2 V. The H3PO4 ionomer also has good wettability with micropore-rich activated carbon, which realizes a capacitance of 210 F g-1 at 200°C. The resulting supercapacitor exhibits an energy density of 32 Wh kg-1 at 3 A g-1 and stable cyclability after 7000 cycles from room temperature to 150°C.

DOI： 10.1038/srep07903

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：人間環境学研究会  

製品生産現場における生産スケジュールの定式化として、フレキシブルジョブスケジューリング問題が研究の対象とされている。各ジョブショップにリソースとして製品（群）・機械・オペレータが割り当てられる研究例は多いが、段取り作業および段取り従事者に注目した研究は見られない。多品種少量生産の現場では、段取り作業者資源の効率的な配分が生産性の向上につながる。一方、人的な資源であるために、従事者の満足度は軽視できない。本研究では、段取り作業者を取り入れたフレキシブルジョブショップ問題を取り上げ、多様性指向型多目的遺伝的アルゴリズムによる解法を提案する。納期遅れ指数と段取り作業者の負荷指数を評価関数とすることで、顧客と作業従事者の視点に立った最適化が可能になった。提案手法により短時間で生産スケジュールを作成することができ、実生産データを用いた場合においても、適用可能なスケジュールを導出することができた。

DOI： 10.4189/shes.13.1

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：Journal of the Electrochemical Society  

Rechargeable fuel-cell batteries (RFCBs) operate by hydrogen storage and release at the anode, while oxygen evolution and reduction reactions occur at the cathode. High-surface-area porous carbon was treated with HNO3 to produce an anode material with carbonyl and phenol groups on the surface, thereby providing redox sites for hydrogen storage and release. The HNO3-activated carbon anodes were characterized with respect to use in a RFCB operated from room temperature to 75°C with a voltage range of 0-2.0 V. The quantity of carbonyl groups and the corresponding reduced phenol groups increased with the O/C atomic ratio of the oxygenated carbon, by which the electrical capacity was increased to reach a maximum of 125 mAh g-1 at an O/C atomic ratio of 0.114. The optimal temperature and charge voltage for performance and cyclability were determined to be 50°C and 1.25 V, respectively. The charge and discharge times remained at ca. 93% of the respective initial values after 300 cycles. The RFCB with the modified porous carbon anode provided energy densities of 2.5-13.8 Wh kg-1 and power densities of 46.4-296.3 W kg-1 (normalized according to the mass of the entire cell).

DOI： 10.1149/2.0581508jes

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

Rechargeable fuel-cell batteries (RFCBs) that employ organic chemical hydrides as hydrogen storage media have potential as nextgeneration power sources; however, the reversible storage and release of hydrogen remains a significant challenge. In particular, the hydrogenation of organic compounds during cell charge is difficult to achieve with 100% conversion. However, this report demonstrates that quinones, especially anthraquinone (AQ), can function as a hydrogen carrier for RFCBs, where AQ is hydrogenated to anthrahydroquinone (AH2Q) during charge and AH2Q is dehydrogenated to AQ during discharge. This redox reaction occurred at a more positive potential than that for hydrogen reduction, so that undesired hydrogen production can be avoided by adjusting the charge voltage to 1 V. The resulting RFCB maintained 100% electrical capacity at room temperature, 91% at 50°C, and 63% at 75°C of the respective initial performance with coulombic efficiencies greater than 90% after 300 cycles. Moreover, the RFCB functioned as a secondary battery with energy densities of 0.8.3.4 Wh kg-1, power densities of 9.5-258.9 W kg-1, and as a fuel cell with power densities of 0.001-0.26 W cm-3. Based on the performance and degradation data, the limitations of this RFCB and directions for future research are discussed.

DOI： 10.1149/2.0611504jes

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

The effect of the addition of copper-doped bismuth-vanadium oxide to yttria-stabilized zirconia (YSZ) on the sinterability and electrical conductivity, especially in reducing atmospheres, has been investigated. When Bi2Cu0.1V0.9O5.35 was used as a sintering aid, the sintering temperature could be reduced to 800°C, whereas the conventional sintering process requires temperatures above 1300°C. Although the conductivity of YSZ with 1.5 mol% Bi2Cu0.1V0.9O5.35 was slightly lower than that of pure YSZ si ntered at 1300°C, no PO2 dependence was observed under reducing conditions (e.g., PO2 = 10-5-10-24 atm), which indicates that the electrolyte is applicable to solid-oxide fuel cells.

DOI： 10.1246/cl.140712

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CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.4172/2169-0022.s1.013

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：一般社団法人情報処理学会  

本論では,多品種の製品の受注生産している中小企業におけるフレキシブルジョブショップスケジューリング問題 (FJSP) の最適化について述べる.問題の目的関数には重み付けした納期遅れと段取り者の負荷の平準化を組み入れ,最適化手法としては島モデルを組み入れた Genetic Algorithm(GA) を開発し,実在する受注生産型の中小企業の生産データを用いて研究を行った.開発した GA の解と納期のみを優先させる EDD(Earliest due date) などのスケジュールによって得た値とを比較し,本手法の有効性を確認した.また,この手法を用いて実在する企業に発生すると考えられるリスク (段取り者の離脱や顧客からの過度な納期短縮要求) とその対策のための投資に関する数値実験を行い,リスクの影響と対策の効果を定量的に評価できることを確認した.本手法は他の目的関数も織り込むことが可能であるので様々な形態の製品やサービスの受注型中小企業の客観的経営判断に寄与できると考えられる.

CiNii Research

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：一般社団法人情報処理学会  

本論では,多品種の製品の受注生産している中小企業におけるフレキシブルジョブショップスケジューリング問題 (FJSP) の最適化について述べる.問題の目的関数には重み付けした納期遅れと段取り者の負荷の平準化を組み入れ,最適化手法としては島モデルを組み入れた Genetic Algorithm(GA) を開発し,実在する受注生産型の中小企業の生産データを用いて研究を行った.開発した GA の解と納期のみを優先させる EDD(Earliest due date) などのスケジュールによって得た値とを比較し,本手法の有効性を確認した.また,この手法を用いて実在する企業に発生すると考えられるリスク (段取り者の離脱や顧客からの過度な納期短縮要求) とその対策のための投資に関する数値実験を行い,リスクの影響と対策の効果を定量的に評価できることを確認した.本手法は他の目的関数も織り込むことが可能であるので様々な形態の製品やサービスの受注型中小企業の客観的経営判断に寄与できると考えられる.

CiNii Research

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：2014 Joint 7th International Conference on Soft Computing and Intelligent Systems, SCIS 2014 and 15th International Symposium on Advanced Intelligent Systems, ISIS 2014  

This paper describes the optimization of a flexible job-shop scheduling problem (FJSP) in small and medium-sized enterprises (SMEs) with make-to-order (MTO) manufacturing of products of many kinds. Incorporating weighted tardiness and setup-worker load balance into the objective function of the problem, we have developed a genetic algorithm (GA) using the island model as an optimization method and conducted a study based on production data of actual MTO manufacturing SMEs. We compared the solutions of the GA developed with the values obtained from schedules for the earliest due dates (EDD) that prioritized only the due dates and confirmed the effectiveness of the proposed method Additionally, we conducted numerical experiments using this technique on the risks likely to arise in actual companies (resignation of setup-workers and excessive demands of a customer for moving the due date forward) and investment of countermeasures. We confirmed that it was possible to evaluate the effects of risks and countermeasures quantitatively. This method can contribute to the objective business judgment of SMEs providing MTO products and services by incorporating other objective functions.

DOI： 10.1109/SCIS-ISIS.2014.7044681

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：人間環境学研究会  

DOI： 10.4189/shes.12.181

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：Molecular Genetics and Metabolism  

Citrin-deficient children and adolescents between adult-onset type II citrullinemia and neonatal intrahepatic cholestasis by citrin deficiency do not have clear clinical features except for unusual diet of high-fat, high-protein, and low-carbohydrate food. The aims of the present study are to characterize fatigue and quality of life (QOL) in citrin-deficient patients during adaptation and compensation stage, and to define the relationship between fatigue and QOL. The study subjects were 55 citrin-deficient patients aged 1-22. years (29 males) and 54 guardians. Fatigue was evaluated by self-reports and proxy-reports of the PedsQL Multidimensional Fatigue Scale. QOL was evaluated by the PedsQL Generic Core Scales. Both scale scores were significantly lower in child self-reports (p< 0.01 and p< 0.05, respectively) and parent proxy-reports (p< 0.01 and p< 0.01, respectively) than those of healthy children. Citrin-deficient patients with scores of 50 percentile or less of healthy children constituted 67.5% of the sample for the Fatigue Scale and 68.4% for the Generic Core Scales. The PedsQL Fatigue Scale correlated with the Generic Core Scales for both the patients (r = 0.56) and parents reports (r = 0.71). Assessments by the patients and their parents showed moderate agreement. Parents assessed the condition of children more favorably than their children. The study identified severe fatigue and impaired QOL in citrin-deficient patients during the silent period, and that such children perceive worse fatigue and poorer QOL than those estimated by their parents. The results stress the need for active involvement of parents and medical staff in the management of citrin-deficient patients during the silent period. © 2013 Elsevier Inc.

DOI： 10.1016/j.ymgme.2013.01.020

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

An anhydrous hydroxide ion conductor, Sn0.92Sb 0.08P2O7, can function as an electrolyte for aluminum-air batteries, where aluminum is oxidized to an aluminate species during discharge, and the aluminate species is reduced to aluminum by charging the cell. This battery generated an open-circuit voltage of ca. 1.6 V with a discharge capacity of ca. 800 mA h g-1electrode. © 2013 The Royal Society of Chemistry.

DOI： 10.1039/c3ta12707a

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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

Works both ways: Phenol was produced by both anodic and cathodic benzene oxidations over the V xO y-Sn 0.9In 0.1P 2O 7 electrode in an electrochemical cell, thus allowing the use of AC electrolysis for phenol production. AC electrolysis was found to be more efficient and selective toward phenol production than DC electrolysis. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/anie.201202159

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PubMed

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

Ion conductor: A series of Sn 1-xA xP 2O 7 (A V=V, Nb, Ta, and Sb) compounds was synthesized, among which Sn 0.92Sb 0.08P 2O 7 (see picture) showed the highest hydroxide ion conductivity in the temperature range of 50-200 °C (0.08 S cm -1 at 100 °C and 0.05 S cm -1 at 200 °C). This high conductivity was also confirmed under fuel-cell-operating conditions. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/anie.201205022

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PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

都市のコンパクト化を進める上で，都市的利用を中止する地区および集結する地区の選定を，QOL（Quality Of Life）指標および市街地維持費を評価値として選定し，遺伝的アルゴリズムを用いて最適化を行った．新潟県旧上越市に適用した結果，QOL最大化の場合，郊外から郊外へ移転し，特に大型病院のある地区や緑地の豊富な地区への集結が最適であることが示された．一方，市街地維持費最小化の場合，地価が低く築年数が経過している住宅の多い地区から撤退し，鉄道駅周辺や商業施設の充実した幹線道路沿線へ集結することが最適であることが示された．さらに，QOLと市街地維持費を共に考慮する両立モデルでは，市街地維持費削減効果の大きい地区から先に撤退し，その後QOLの向上につながる移転を行うことが最適であることが分かった．

DOI： 10.2208/jscejipm.68.i_339

CiNii Research

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

CiNii Research

記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

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

Fuel cells with a PtAu/C anode and a Pr-doped Mn2O3/C cathode were stacked without using a bipolar plate, and their discharge properties were investigated in a methanol aqueous solution bubbled with air. A three-cell stack exhibited a stack voltage of 2330 mV and a power output of 21 mW. © The Royal Society of Chemistry 2011.

DOI： 10.1039/c1cc10493d

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PubMed

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 エネルギー・資源学会  

The present study evaluated the optimized operation management of a cold air power system at a large-scale medical facilityduring the summer, when the air-conditioning cold load reaches the annual maximum. The evaluation was conducted withrespect to energy costs, CO₂ emissions and robustness of the energy-supply system. Since there are a large number ofpossible solutions as to which machines and which refrigeration levels should be operated, a genetic algorithm (GA) wasused to obtain approximate, applicable solutions stochastically, to determine a daily plan of operation for the refrigerationsystem in a timely manner. According to the operation management plan obtained from the GA, over 10% of the energy costsand the CO₂ emissions can be reduced by improved operation. The stability of the cold air power system when a large-sizedphotovoltaic system is installed or when one of the refrigeration units breaks down can also be evaluated by using the GA. Ina medical faculty we taken up, the estimated reduction in CO₂ by adopting the photovoltaic system was calculated to be about16% compared to the current operation management plan. And also the stability of present energy-supply system wasvalidated except for when the vapor-absorption-type refrigerator was down.

DOI： 10.24778/jjser.32.5_24

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：Energy and Environmental Science  

Fuel cells for vehicular and residential applications have encountered a key technical challenge in cost reduction. This challenge can be avoided by operating a fuel cell stack without the use of gas separators, which are expensive and voluminous and therefore comprise a significant portion of the cost of a fuel cell stack. Single-chamber fuel cells (SCFCs) have the potential of realizing such operation, because there is no need for separation between fuel and air. In this paper, we present a selective anode (PtAu/C) and cathode (Pr-doped Mn2O3/C) for respective electrochemical hydrogen oxidation and oxygen reduction reactions in a SCFC. A single cell with these electrodes operated at 50 °C generated an open-circuit voltage of 1204 mV and a peak power density of 50 mW cm-2 in a feed mixture of 80% hydrogen and 20% air at a flow rate of 30 mL min-1. The high selectivity of these electrodes also enabled the design of two different separator-free fuel cell stacks, parallel and perpendicular to the gas stream. Both cell stacks exhibited increasing stack voltage and power output almost proportionally to the increase in the number of single cells. These results demonstrate that the separator-free fuel cell stack shows high potential for a significant reduction of the cost of fuel cell systems. © The Royal Society of Chemistry.

DOI： 10.1039/c0ee00288g

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記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

今後世界的な問題となることが危惧されている水環境問題の解決策として、下水の適正処理が行われる条件をシステムダイナミクスの手法を用いて導出した。本モデルで越流の予測とその程度の評価を行うことができた。

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

The feasibility of applying single-chamber solid oxide fuel cells (SC-SOFCs) to power generators for exhaust energy recovery was investigated using both model and actual exhaust gases. In the experiments with model exhaust gases, a single cell, Ni-Ce0.8Sm0.2O1.9/YSZ/ La0.8Sr0.2MnO3, was operated in a mixture of gases containing ppm levels of CH4, C2H6, C3H3, C4H10and O2. The cell performance was considerably affected by the molar ratio of total hydrocarbons to O2, the operating temperature and the gas flow rate. The optimal operating conditions of the SC-SOFC were found to be similar to those found in actual exhaust from gasoline engines. Thermal and mechanical loading performance tests demonstrated high tolerance towards thermal cycling and breakage of the electrolyte. Performance tests with and without a gas separator suggested that there is no requirement for a gas separator in an actual exhaust. In the experiments with actual exhaust gases, a 12-cell stack was installed to a 250-cm3 engine. The open circuit voltages (OCVs) were between 5 and 8 V and independent of the number of revolutions, but were lower than the values expected from the model exhaust results. This was considered to be due to the deviation of the actual exhaust gases from the model gases. Nevertheless, the stack performance was reproducible and stable in the range from 1,500 to 5,500 rpm. The resultant peak power reached above 1 W at 4,500 rpm. © 2008 WILEY-VCH Verlag GmbH & Co. KGaA.

DOI： 10.1002/fuce.200800017

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

An electrochemical cell using an In3+-doped SnP2O7 proton conductor as the electrolyte exhibited comparable NO reduction and sensing properties at around 250 °C. NO was reduced to N2 most effectively when using a PtRhBa/C cathode by applying current to the cell. High electrocatalytic activity was maintained even in the presence of CO2 and H2O. PtRhBa/C was also found to be the most effective electrode material for NOx sensing. The sensor exhibited electromotive force (EMF) response towards the positive direction with increasing NO and NO2 concentrations. The polarization curves of NO/NO2 and water vapor indicated that the sensing mechanism is based on the mixed potential. The effects of added Rh and Ba to the Pt/C electrode were explained in terms of selective reduction and adsorption of NO/NO2 over the electrode surface, respectively. © 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ssi.2008.03.033

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

Pt-free fuel cells were investigated using a proton-conducting Sn0.9In0.1P2O7 electrolyte at intermediate temperatures between 150 and 300 °C. Transition metal oxides were applied as non Pt cathode catalysts. A ZrO2/C catalyst showed the highest catalytic activity for the oxygen reduction reaction among the metal oxides tested. The catalytic activity of ZrO2/C was further improved by optimizing the heat-treatment temperature for ZrO2/C. XRD measurements revealed that the high catalytic activity was attributed to the crystal structure of tetragonal ZrO2. Finally, we evaluated performance of a Pt-free fuel cell using the ZrO2/C cathode with a Mo2C-ZrO2/C anode that shows Pt-like behavior in reducing atmospheres. Reasonable performance was achieved by operating the Pt-free fuel cell at intermediate temperatures above 200 °C. © 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ssi.2007.12.090

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

Direct dimethyl ether fuel cells (DDMEFCs) were investigated using proton-conducting Sn0.9 In0.1 P2 O7 as an electrolyte at intermediate temperatures between 150 and 300°C. Fuel cell operation at intermediate temperatures allowed a PtC anode to achieve excellent CO tolerance and high catalytic activity for the anode reaction of DME. The catalytic activity of the PtC anode was further improved by the addition of Ru to Pt, especially at elevated temperatures. The anodic overpotential and anode product measurements revealed that the H2 produced by the reforming reaction of DME was electrochemically oxidized at the PtRuC anode, which proceeded in parallel with the direct oxidation reaction of DME. As a result, DDMEFCs with the PtRuC anode achieved a peak power density of 31, 52, and 78 mW cm-2 at 200, 250, and 300°C, respectively. © 2007 The Electrochemical Society.

DOI： 10.1149/1.2803509

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Electrochemical and Solid-State Letters  

Proton-conducting composite membranes were fabricated by blending Sn0.95 Al0.05 P2 O7 having an excess of phosphates with polybenzimidazole (PBI) and polytetrafluoroethylene (PTFE). The addition of PBI to Sn0.95 Al0.05 P2 O7 - Px Oy powder stabilized the conductivity of the composite, providing higher conductivities than those of stoichiometric Sn0.95 Al0.05 P2 O7. The addition of PTFE to Sn0.95 Al0.05 P2 O7 - Px Oy -PBI powder reduced the conductivity but increased the tensile strength. The resulting composite membrane exhibited a conductivity of 0.04 S cm-1 at 200°C and a tensile strength of 2.30 MPa. Moreover, a fuel cell made with this composite membrane yielded high power densities exceeding 200 mW cm-2 above 100°C and good durability under unhumidified conditions. © 2008 The Electrochemical Society.

DOI： 10.1149/1.2897758

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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：Electrochemical and Solid-State Letters  

Heat engines emit huge amounts of exhaust which contain considerable quantities of heat and chemical energies. An increasing public awareness of global warming and oil depletion has required the development of innovative methods of recovering energy from such exhaust. A promising approach is to produce electricity from unburned fuel by using a fuel cell system. The exhaust includes cracked-light hydrocarbons, offering the possibility of applying this system to a power generator. Solid oxide fuel cells (SOFCs) can work at elevated temperatures but have poor thermal and mechanical shock resistance. In this study, we address this problem by operating the fuel cell system in a single-chamber mode, wherein no separation between fuel and oxidant gases is required. This operation provides high tolerance toward thermal cycling and breakage of the electrolyte. As a result, a twelve-cell stack exhibits stable and high performance in the exhaust from a motorcycle. © 2007 The Electrochemical Society.

DOI： 10.1149/1.2824502

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

単室形燃料電池は燃料と酸素の混合ガス中で発電が可能である。そのため、エンジン排ガス中に含有する未燃焼燃料を用いての発電が可能である。さらに構造的にスタック化も有利であり、実際にエンジン直下に取り付けたところ、スタック枚数に応じて出力を得ることができた。

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 Catalysis  

The selective catalytic reduction (SCR) of NOx by H2 was studied using proton-conducting Sn0.9In0.1P2O7 as a catalyst support at 50-350 °C. When a mixture of 800 ppm NO, 1400-8400 ppm H2, and 5% O2 in Ar was introduced to the Pt/C working electrode, NOx was reduced to N2 with N2 selectivity values > 80 %. The reaction mechanism was shown to be based on a mixed potential at the Pt/C working electrode. This mechanism was also applicable to a Sn0.9In0.1P2O7-supported Pt catalyst. H2 SCR over the Pt/Sn0.9In0.1P2O7 catalyst was characterized by a wide operating temperature window (50-350 °C) and remarkable N2 selectivity values (> 80 %). Catalyst performance could be further improved by the addition of Rh to Pt, in which NOx conversion was a maximum 1.4 times higher than that over the Pt/Sn0.9In0.1P2O7 catalyst and N2 selectivity was increased to > 89 % at all temperatures tested. © 2007 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcat.2007.02.001

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Scopus

記述言語：英語  

A proton conducting, 10 mol% In3+-doped SnP2O7 was characterized by TGA, TEM measurement, and electrochemical techniques. We prepared Sn0.9In0.1P2{plus minus}xO7{plus minus}x samples with various P/(Sn+In) molar ratios from 1.7 to 2.6. Sn0.9In0.1P2O7 with a stoichiometric P/(Sn+In) molar ratio of 2.0 showed a proton conductivity of about 0.19 S cm-1 at 250oC under unhumidified conditions. When the P/(Sn+In) molar ratios were over 2.0, amorphous layer composed of phosphorus compounds were observed over the surface of Sn0.9In0.1P2O7 particles. The proton conductivity slightly increased with increasing the P/(Sn+In) molar ratios from 2.0 to 2.6. It is considered that the amorphous layer enhanced the proton conductivity by surface conduction. On the other hand, the thermal stability of this amorphous layer during heating-cooling cycle was not enough high to apply to electrochemical devises. It is important to prepare Sn0.9In0.1P2O7 with the P/(Sn+In) molar ratio of 2.0 to achieve both sufficient proton conductivity and high thermal stability.

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  

Anode performance of non-Pt catalysts for hydrogen oxidation was investigated in intermediate-temperature proton exchange membrane fuel cells. Molybdenum carbide (Mo2 C) showed the highest catalytic activity among the transition metal carbides tested. Furthermore, the catalytic activity of Mo2 C was significantly improved by the addition of ZrO2 to the anode. Transmission electron microscopy and X-ray diffraction measurements revealed that Mo2 C was more highly dispersed in the Mo2 C- ZrO2 C than in the Mo2 CC, suggesting that the particle growth of Mo2 C was suppressed by the addition of ZrO2. We also tested the performance of a fuel cell using Mo2 C- ZrO2 C and Sn0.9 In0.1 P2 O7 as the anode and electrolyte materials, respectively, between 150 and 300°C. At 250°C or higher, the Mo2 C- ZrO2 C anode showed a cell performance comparable to that of the PtC anode. However, cell performance was strongly dependent on the operating temperature, reflecting that the catalytic activity of Mo2 C- ZrO2 was greatly lowered by the decrease in operating temperature. Thus it was concluded that the Mo2 C- ZrO2 catalyst is a promising alternative anode material to Pt, especially at intermediate temperatures. © 2006 The Electrochemical Society.

DOI： 10.1149/1.2382268

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Scopus

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

Al3+ -doped Sn P2 O7 proton conductors were prepared by controlling the initial composition of the reactants [Sn O2, Al (OH)3, and H3 P O4]. Sn1-x Alx Py Oz with y<2 displayed conductivities approximately two orders of magnitude lower than Sn1-x Alx P2 O7, while those of Sn1-x Alx Py Oz with y>2 exhibited conductivities at a maximum of 1.99 times higher. However, because the conductivity values of Sn1-x Alx Py Oz with y>2 were not stable, the optimal value of y in Sn1-x Alx Py Oz was determined to be 2. Partial substitution of Al3+ for Sn4+ in Sn1-x Alx P2 O7 led to an increase in the conductivity up until x=0.05. As a result, the conductivity reached 0.045 S cm-1 at 100°C, 0.15 S cm-1 at 200°C, and 0.19 S cm-1 at 300°C when the x and y values were 0.05 and 2, respectively. A hydrogen concentration cell with this material demonstrated that the ionic transport number was ∼1, and a fuel cell using this material demonstrated that the dc conductivity was comparable to the ac conductivity. © 2007 The Electrochemical Society.

DOI： 10.1149/1.2789296

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Scopus

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

An anhydrous proton conductor, 10 mol % In3+ -doped SnP2 O7 (Sn0.9 In0.1 P2 O7), was composed by 1,8-bis(triethoxysilyl)octane (TES-Oct) and 3-(trihydroxysilyl)-1-propanesulfonic acid ((THS)Pro- SO3 H) and was characterized by structural and electrochemical analysis. The composite membrane with 90 wt % Sn0.9 In0.1 P2 O7 showed high proton conductivities of 0.04 S cm-1 or more between 150 and 200°C in unhumidified air. The packing of the Sn0.9 In0.1 P2 O7 particles in the matrix was relatively uniform, with no formation of pinholes observed. Fuel cell tests verified that the open-circuit voltage was maintained at a constant value of ∼970 mV regardless of the electrolyte thickness (60-200 μm), while the Ohmic resistance was decreased to 0.24 cm2 by reducing the electrolyte thickness to 60 μm. The peak power densities achieved with unhumidified H2 and air were 109 mW cm-2 at 100°C, 149 mW cm-2 at 150°C, and 187 mW cm-2 at 200°C. Furthermore, fuel cell performance was improved by hot-pressing an intermediate layer consisting of Sn0.9 In0.1 P2 O7, PtC, TES-Oct, and (THS)Pro- SO3 H between the electrolyte and cathode. © 2006 The Electrochemical Society.

DOI： 10.1149/1.2388737

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Scopus

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

An anode-supported single-chamber solid oxide fuel cell (SC-SOFC), consisting of a Ce0.9 Gd0.1 O1.9 electrolyte, a Ni- Ce0.8 Sm0.2 O1.8 (SDC) cermet anode, and a Sm0.5 Sr0.5 Co O3 cathode, was operated in a mixture feed of dimethyl ether (DME), ethanol or butane, and air at a furnace temperature of 300°C. This SC-SOFC showed comparatively poor performance for DME and ethanol fuels when compared to the performance for butane fuel, resulting from the relatively small difference in catalytic activity for DME and ethanol oxidation between the anode and the cathode. An effective improvement was achieved by attaching Ru/SDC/Ni and CuZnAl catalyst layers for DME and ethanol, respectively, on the anode surface. As a result, peak power densities of 64 and 117 mW cm-2 were obtained for DME and ethanol, respectively. © 2007 The Electrochemical Society.

DOI： 10.1149/1.2747326

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Scopus

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

A potentiometric solid-state gas sensor was fabricated using a proton-conducting Sn0.9 In0.1 P2 O7 electrolyte with an active PtC working electrode in order to study its sensing properties for small quantities (100 ppm 3%) of H2 in air at room temperature. The sensor showed electromotive force (emf) response in the negative direction to changes in the H2 concentration. Furthermore, the emf value varied linearly with the logarithm of the H2 concentration, while it was minimally affected by the water-vapor concentration. The sensing mechanism was shown to be based on the mixed potential at the working electrode through measurements of the polarization curves of H2 and air. The Sn0.9 In0.1 P2 O7 electrolyte was also applied in two single-chamber H2 sensors, wherein PtC and carbon were used as active and inactive electrodes, respectively; these electrodes were attached on the opposite surfaces or on the same surface of the electrolyte. Both single-chamber sensors could exhibit comparable H2 sensitivities, compared to the dual-chamber sensor. © 2007 The Electrochemical Society.

DOI： 10.1149/1.2713702

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Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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：Electrochemical and Solid-State Letters  

We report proton conduction in In3+ -doped Sn P2 O7 in the temperature range from 100 to 300°C, and the performance of a H2 -air fuel cell using this material as the electrolyte. The proton conductivity of In3+ -doped Sn P2 O7 was more than 10-1 S cm-1 between 125 and 300°C, and a conductivity value of 1.95× 10-1 S cm-1 was achieved at 250°C. The resulting fuel cell exhibited a reasonable power density of 264 mW cm-2 at 250°C (electrolyte thickness=0.35 mm), together with perfect tolerance toward 10% CO and good thermal stability in unhumidified conditions. © 2006 The Electrochemical Society. All rights reserved.

DOI： 10.1149/1.2159298

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Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Electrochemical and Solid-State Letters  

In 3+-doped SnP 2O 7 was used as the electrolyte in an electrochemical cell for the reduction of NO between 150 and 300°C in the presence of excess O 2. NO was reduced to N 2 at a Pt/C cathode when current was applied to the cell. The electrocatalytic activity of the cathode for the reduction of NO was shown to be highest at 250°C. The addition of Ba species (an oxide/carbonate mixture) to the cathode further promoted the reduction of NO by adsorbing NO more selectively than O 2 on the surface. A resulting current efficiency of 5.81% was achieved in a 2% O 2 atmosphere. © 2005 The Electrochemical Society. All rights reserved.

DOI： 10.1149/1.2149213

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Scopus

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

Multilayered Ce0.9 Gd0.1 O1.95 Ba Ce0.8 Y0.2 O3-α Ce0.9 Gd0.1 O1.95 (GDCBCYGDC) electrolytes were prepared by tape casting on a Ni- Ce0.8 Sm0.2 O1.9 anode support. The overall electrolyte thickness ranged from 30 to 35 μm, including a 3 μm thick BCY layer. When the multilayered electrolyte cell was tested with hydrogen at the anode and air at the cathode in the temperature range of 500-700°C, it yielded open-circuit voltages (OCVs) of 846-1024 mV, which were higher than the OCVs of 753-933 mV obtained for a single-layered GDC electrolyte cell under the same conditions. The corresponding peak power densities reached 273, 731, and 1025 mW cm-2 at 500, 600, and 700°C, respectively. The multilayered electrolyte cell could also be applied to direct methane solid oxide fuel cell (SOFC) and single-chamber SOFC operating in a mixture of methane and air. These SOFCs yielded OCVs of 880-950 mV and reasonable power densities without coking. © 2006 The Electrochemical Society.

DOI： 10.1149/1.2186184

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：Electrochemical and Solid-State Letters  

A potentiometric NOx sensor using a proton-conducting Sn0.9 In0.1 P2 O7 electrolyte with a PtRhC working electrode was fabricated to study sensing properties for NO and N O2 at intermediate temperatures. The sensor showed electromotive force (emf) responses to changes in NO and N O2 concentrations. Interestingly, the emf values for both NO and N O2 increased in the positive direction with increasing gas concentration. The sensing mechanism was shown to be based on a mixed potential at the working electrode through measurements of the polarization curves of NO or N O2 and water vapor. © 2006 The Electrochemical Society.

DOI： 10.1149/1.2193073

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：ECS Transactions  

A proton conducting, 10 mol% In3+-doped SnP2O 7 (Sn0.9In0.1 P2O7) was characterized by thermogravimetric analysis (TGA), transmission electron microscope (TEM) measurement, and electrochemical techniques. We prepared Sn0.9In0.1P2=x07±x samples with various P/(Sn+In) molar ratios from 1.7 to 2.6 through the control of the amount of phosphoric acid at the preparation process in order to examine electrochemical properties and thermal stabilities. Sn0.9In 0.1P2O7 with a stoichiometric P/(Sn+In) molar ratio of 2.0 showed a proton conductivity of about 0.19 S cm-1 at 250°C under unhumidified conditions. When the P/(Sn+In) molar ratios were over 2.0, the formation of amorphous layer composed of phosphorus compounds were observed over the surface of Sn0.9In0.1P 2O7 particles. The proton conductivity slightly increased with increasing the P/(Sn+In) molar ratios from 2.0 to 2.6. It is considered that the amorphous layer enhanced the proton conductivity by surface conduction. On the other hand, the thermal stability of this amorphous layer during heating-cooling cycle was not enough high to apply to electrochemical devises. As a result, it is important to prepare Sn0.9In0.1P 2O7 with the P/(Sn+In) molar ratio of 2.0 to achieve both sufficient proton conductivity and high thermal stability. Copyright The Electrochemical Society.

DOI： 10.1149/1.2408942

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  

SnP2 O7 -based proton conductors were characterized by Fourier transform infrared spectroscopy (FTIR), temperature-programmed desorption (TPD), X-ray diffraction (XRD), and electrochemical techniques. Undoped SnP2 O7 showed overall conductivities greater than 10-2 S cm-1 in the temperature range of 75-300°C. The proton transport numbers of this material at 250°C under various conditions were estimated, based on the ratio of the electromotive force of the galvanic cells to the theoretical values, to be 0.97-0.99 in humidified H2 and 0.89-0.92 under fuel cell conditions. Partial substitution of In3+ for Sn4+ led to an increase in the proton conductivity (from 5.56× 10-2 to 1.95× 10-1 S cm-1 at 250°C, for example). FTIR and TPD measurements revealed that the effects of doping on the proton conductivity could be attributed to an increase in the proton concentration in the bulk Sn1-x Inx P2 O7. The deficiency of P2 O7 ions in the Sn1-x Inx P2 O7 bulk decreased the proton conductivity by several orders of magnitude, which was explained as due to a decrease in the proton mobility rather than the proton concentration. The mechanism of proton incorporation and conduction is examined and discussed in detail. © 2006 The Electrochemical Society. All rights reserved.

DOI： 10.1149/1.2210669

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Scopus

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

Performance of a fuel cell using Sn0.9 In0.1 P2 O7 as the electrolyte was evaluated in the temperature range of 150-300°C under unhumidified conditions. The IR drop and electrode overpotential of the cell were measured separately by the current interruption method. The dc conductivity values of the electrolyte between 150 and 300°C, estimated from the IR drop, were comparable to the ac conductivity values (1.48× 10-1 -1.95× 10-1 S cm-1) of the electrolyte. The cell performance was improved by forming an intermediate layer consisting of Sn0.9 In0.1 P2 O7 and PtC catalyst powders at the interface between the electrolyte and cathode, which significantly reduced the cathode polarization. As a result, the peak power density reached 264 mW cm-2 at 250°C using the 0.35-mm -thick electrolyte. The present fuel cell also showed high stability at low relative humidities (p H2 O ≈0.0075 atm) and 10% CO concentration. © 2006 The Electrochemical Society. All rights reserved.

DOI： 10.1149/1.2183927

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：ECS Transactions  

Proton exchange membrane fuel cells (PEMFCs) are among the most promising power sources for vehicular and residential applications because of their clean and efficient energy conversion. However, these fuel cells require expensive Pt-based electrodes, which raise the cost of fuel-cell systems considerably. Here, we propose an approach to solving this problem by combining a molybdenum carbide (Mo2C) catalyst with an In3+-doped SnP 2O7 electrolyte. The resulting fuel cell can operate in the temperature range of 150 to 300°C, providing the high catalytic activity of Mo2C for electrochemical hydrogen oxidation, which is comparable to that of a Pt anode catalyst. Another important advantage of this fuel cell is that the Mo2C anode catalyst showed perfect tolerance to 10%CO. copyright The Electrochemical Society.

DOI： 10.1149/1.2356166

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

CiNii Research

担当区分：筆頭著者   記述言語：日本語   掲載種別：論文集(書籍)内論文  

200度程度で作動するプロトン導電体に関する報告を中心に、世界の開発動向をまとめた総説である。

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Single-chamber solid oxide fuel cells (SOFCs) with an anode-supported Ce0.9Gd0.1O1.95 electrolyte were operated in a mixture of butane and air at furnace temperatures of 200-300°C. The electromotive force (emf) of the cell and the voltage drop were strongly influenced by the catalytic activity of the anode for the partial oxidation of butane. The promotion of hydrogen formation by the addition of Ru to the anode caused an increase in the emf and a reduction in the voltage drop. As a result, stable power densities of 44 and 176 mW cm–2 were obtained at 200 and 300°C, respectively.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

A method that can block off electronic current through a samaria-doped ceria (SDC, Ce0.8Sm0.2O1.9) electrolyte is proposed. A thin BaCeO3-based layer 12 &micro;m thick was grown by a solid-state reaction of the electrolyte substrate and a BaO film deposited previously over the substrate surface at 1500°C. A homogeneous junction between the layer and the electrolyte was formed, thus allowing no delamination and cracking of the layer. Tolerance of this layer to CO2 was high enough to suppress decomposition into BaCO3 and CeO2. Open-circuit voltages of a hydrogen-air fuel cell with the coated SDC electrolyte were near 1 V or more in the range of 600-950°C. The resulting peak power density was higher than that of a fuel cell with an uncoated SDC electrolyte.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

We proposed a new type of solid oxide fuel cell (SOFC) operating without using an anode material, where the anode was spontaneously formed by reduction of the electrolyte surface under reducing gas conditions. A BaCe0.76Y0.20Pr0.04O3−α electrolyte most successfully met this criterion. This material showed high mixed protonic–electronic conduction, whereas the open circuit voltage (OCV) of the cell was slightly lower than the theoretical value. The resulting SOFC exhibited reasonable fuel cell performances together with a good stability to thermal and redox cyclings and high resistance to carbon deposition up to 800 °C for dry methane, ethane, and propane.

Author Keywords: Solid oxide fuel cells; BaCe0.76Y0.20Pr0.04O3−α; Anode material

記述言語：英語   掲載種別：研究論文（学術雑誌）  

開催年月日： 2020年7月

記述言語：英語   会議種別：口頭発表（招待・特別）  

開催地：Webinar   国名：日本国  

開催年月日： 2017年8月 - 2017年9月

記述言語：英語   会議種別：口頭発表（招待・特別）  

開催地：Kyoto, Japan   国名：日本国  

開催年月日： 2015年11月

記述言語：英語   会議種別：口頭発表（招待・特別）  

開催地：Thailand   国名：タイ王国  

開催年月日： 2013年10月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：大阪   国名：日本国  

開催年月日： 2013年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：南山大学   国名：日本国  

開催年月日： 2009年5月

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2008年3月

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

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