研究者データベース
大橋 秀伯OHASHI Hidenoriオオハシ ヒデノリ
| ■所属部署名 | 工学部 化学物理工学科 | |||
| ■職名 | 准教授 | |||
Last Updated :2025/01/22
業績情報
氏名・連絡先
氏名
オオハシ ヒデノリ, 大橋 秀伯, OHASHI Hidenori
主たる所属・職名
工学部 化学物理工学科, 准教授
その他の所属
教育・研究活動状況
- 省エネルギー技術として有望な、機能膜を用いた分離技術の研究を行っています。新しい膜分離技術の開拓や機能膜そのものの開発にとどまらず、膜性能に大きな影響を与える膜中のミクロな分子運動（移動物性・モビリティ）にも着目しています。
科学研究費助成事業
- 国際共同研究加速基金（国際共同研究強化(B)）（令和３(2021)以降採択分）
固体高分子電解質/電極界面設計技術を基盤とするフレキシブルLi金属二次電池の創出
自 2023年, 至 2023年 - 基盤研究(C)
ビニルポリマーが潜在的に持つ分離機能を引き出すための研究
自 2023年, 至 2025年 - 国際共同研究加速基金（国際共同研究強化(B)）
固体高分子電解質/電極界面設計技術を基盤とするフレキシブルLi金属二次電池の創出
自 2022年, 至 2022年 - 基盤研究(C)
酵素の高度リサイクルに向けたグラフトリフォールディング手法の開発
自 2018年, 至 2020年 - 基盤研究(A)
ペプチドアプタマーを用いた分子認識診断膜およびシステムの設計・開発
自 2018年, 至 2018年 - 基盤研究(A)
ペプチドアプタマーを用いた分子認識診断膜およびシステムの設計・開発
自 2017年, 至 2017年 - 基盤研究（A）
ペプチドアプタマーを用いた分子認識診断膜およびシステムの設計・開発
自 2016年, 至 2016年
論文
- A review on TMDCs nanomaterials and their surface engineered polymeric membrane nanocomposites for water remediation and wastewater treatment
Kayanja, Oscar; Abdel-Aty, Ahmed. A. R.; Hassan, Mohsen A.; Hassanin, Ahmed; Ohashi, Hidenori; Khalil, Ahmed S. G.
SURFACES AND INTERFACES
ELSEVIER
Transitional metal dichalcogenides (TMDCs) have lately attracted attention as viable two-dimensional (2D) materials capable of enhancing the performance of membrane-based technologies for wastewater treatment. The dispersion of TMDCs in nanocomposite membranes seems to have established diverse alternatives to control membrane surface properties as well as the antifouling behaviour. This is possible due to the ability to manip-ulate the 2D structure of TMDCs along the processing stage, which creates the necessary building blocks to design and fabricate membranes with improved separation performance. Recent research has revealed that 2D TMDCs possess better performance indicators than graphene and its functional derivatives due to their outstanding mechanical, biological, and physicochemical properties which could be inherent when blended with polymeric materials to formulate membrane composites. Very few reviews have tackled a detailed discussion about the separation performance of TMDCs based membranes for wastewater treatment and in here, a detailed discussion is made. In this review, TMDC nanomaterials and their polymeric membrane nanocomposites are discussed in detail for water remediation and wastewater treatment. Several TMDCs are described with regard to their low-cost synthesis procedures in addition to vital characterization techniques utilized to analyse these materials. This is followed by a thorough discussion about synthesis and characterization employed to analyse the effect and dispersion of TMDCs in polymeric membranes to form nanocomposite membranes. Finally, an analysis for the role of using TMDC-based nanocomposite membranes for wastewater treatment is made and the rejection mechanisms that have been concluded from recent studies are also discussed. This review has focused on novel areas that are overlooked by a few reviews published in this area, with regard to using TMDCs in modifying polymeric membranes for water remediation and wastewater treatment.
2023年12月, 研究論文（学術雑誌）, 共同, 43, 2468-0230, DOI(公開)(r-map) - Preparation of a poly(2-acrylamido-2-methyl-1-propanesulfonic acid)-grafted polyurethane sponge using atmospheric pressure plasma-induced graft polymerization and its catalytic properties for the acetalization of glycerol to solketal
Tokuyama, Hideaki; Suzuki, Hikaru; Terada, Akihiko; Ohashi, Hidenori
REACTIVE & FUNCTIONAL POLYMERS
ELSEVIER
Poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (poly(AMPS)) bearing a sulfo group was grafted onto a polyurethane sponge by an argon atmospheric-pressure plasma treatment and subsequent graft polymerization. Thus, a novel poly(AMPS)-grafted polyurethane sponge was developed as a heterogeneous acid catalyst for organic synthesis. The average grafting amount was 0.0277 kg-polymer/kg-substrate. The surface properties of the polyurethane sponge changed considerably, from hydrophobic to hydrophilic. The poly(AMPS)-grafted sponge successfully catalyzed the acetalization of glycerol with acetone to produce the desired solketal. The reaction rate was analyzed using a pseudo-first-order kinetic model, and the apparent reaction rate constant, k, and apparent activation energy were determined. The k value for the poly(AMPS)-grafted sponge was one order of magnitude larger than that for the EDGA-co-AMPS gel (EDGA: ethoxy diethyleneglycol acrylate). The poly (AMPS)-grafted sponge with interconnected submillimeter-sized macropores and high porosity (98%) exhibits excellent diffusional permeability. In addition, the structural features of the sponge provide advantages such as a negligible pressure drop and easy handling during the reaction process. This study provides a strategy for the use of polymers grafted onto sponges as catalysts.
2023年10月, 研究論文（学術雑誌）, 共同, 191, 1381-5148, DOI(公開)(r-map) - Effect of phase disparity of MoS2 nanosheets on the performance of PES membranes for dual industrial oil-in-water emulsion separation and dyes adsorption
Oscar Kayanja, Mohsen A. Hassan, Ahmed Hassanin, Hidenori Ohashi, Ahmed S. G. Khalil
Process Safety and Environmental Protection
ELSEVIER
Water shortage is a global challenge due to increased demand and hence, reliable wastewater treatment avenues must be created to solve this problem. In this work, we report about the fabrication of dual performance pol-yethersulfone (PES) membranes modified with molybdenum disulfide (MoS2) nanosheets of different phases for wastewater remediation. We optimised process parameters to obtain large area, defect free membrane sheets. Comprehensive characterization revealed the phase disparity of MoS2, and changes introduced in the modified PES membranes. Blending MoS2 with PES membranes enhanced the mechanical properties as well as water uptake differently. The optimum PES membrane was modified with 0.2 wt% of 70% 1 T/2 H MoS2 and possessed superior pure water permeance of 778 kg/m2.h.bar. It also showed superior performance towards oil removal with rejection efficiency of 99% for 1 g/L oil concentration and it revealed excellent antifouling properties. The optimum membrane showed appreciable performance in organic dye rejection, even though it was outpaced by the 0.5 wt% of 70% 1 T/2 H MoS2 modified PES with a dye rejection of 98% towards methylene blue and 92% towards Rhodamine B. This work revealed that the phase of MoS2 strongly influences the structure and per-formance of the resultant PES-based nanocomposite membranes in ultrafiltration applications.
2023年03月, 研究論文（学術雑誌）, 共同, 171, 0957-5820, DOI(公開)(r-map), 55, 70 - Low humidity dependence of proton conductivity in modified zirconium(iv)-hydroxy ethylidene diphosphonates
Ogawa, Takaya; Anilkumar, Gopinathan M.; Tamaki, Takanori; Ohashi, Hidenori; Yamaguchi, Takeo
MATERIALS CHEMISTRY FRONTIERS
ROYAL SOC CHEMISTRY
Materials with proton-conducting properties have attracted much interest and play a key role in various processes and devices such as polymer electrolyte fuel cells. In these materials, the major issue is the strong dependence of the proton conductivity on the relative humidity (RH); conductivity severely decreases under low RH conditions. Here we report the synthesis of zirconium-hydroxy ethylidene diphosphonates (ZrHEDP), in which the phosphonic acid groups are placed at a closer distance. As the acid groups are more concentrated in ZrHEDP, the proton conductivity exhibits lower dependence on the RH. In particular, the ZrHEDP with the largest number of phosphonic acid groups among the examined samples showed the lowest RH dependence; the proton conductivity at 40% RH remained 2/3 of the conductivity at 95% RH, whereas a well-known proton-conducting material, Nafion, at 40% RH showed 1/5-1/20 of its conductivity at 95% RH.
2022年10月24日, 研究論文（学術雑誌）, 共同, 6, 21, DOI(公開)(r-map), 3271, 3278 - Low-Fouling Polyvinylidene Fluoride Microfiltration Membranes Produced by Grafting Carboxybetaine Polymers by Atom Transfer Radical Polymerization and Activator Generated by Electron Transfer-Atom Transfer Radical Polymerization
Akamatsu, Kazuki; Shida, Taisei; Ochiai, Ayaka; Fukase, Ryo; Ohashi, Hidenori; Nakao, Shin-ichi; Wang, Xiao-lin
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
AMER CHEMICAL SOC
membranes were first developed by grafting a carboxybetaine polymer (PCMB) onto the surface and pore walls. Two grafting procedures were investigated. One was atom transfer radical polymerization (ATRP), and the other was activator generated by electron transfer ATRP (AGET-ATRP). In both methods, the Fenton reaction followed by the initiator immobilization was carried out prior to ATRP or AGET-ATRP. Although there was a difference in the grafting rate, it was possible to control the grafting amount by governing the grafting time in both methods. The grafting of PCMB had two opposite effects on the performance of the membrane: it increased its low-fouling property and decreased its pure water permeability. Pure water permeability measurements and filtration tests using aqueous solution containing BSA revealed that the optimum grafting amount that achieved excellent lowfouling while retaining high pure water permeability was 0.17-0.2 mg cm-2. We also investigated cleaning the fouled membrane with a sodium hydroxide solution at pH 11. The treated membrane indicated the recovery of pure water permeability and the preservation of the low-fouling property.
2022年10月05日, 研究論文（学術雑誌）, 共同, 61, 39, 0888-5885, DOI(公開)(r-map), 14649, 14655 - Effect of Structural Features of Polymer Gels Containing Au Nanoparticles on Their Catalytic Properties
Kato, Gakuto; Doi, Hayato; Ohashi, Hidenori; Tokuyama, Hideaki
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
SOC CHEMICAL ENG JAPAN
Au(0) nanoparticles catalyze many reactions and various Au-polymer composites have been developed to date. Herein, we developed different types of Au(0)-nanoparticle-loaded gels and investigated the effects of their structural features such as the polymer type, gel diameter, and gel composition on their catalytic properties. N-isopropylacrylamide (NIPA) gel, N,N-dimethylacrylamide (DMAA) gel, poly(ethylene glycol) diacrylate (PEGDA) gel, and poly(ethylene glycol) methyl ether acrylate (PEGMEA) gel were used, and millimeter-, micrometer-, and nanometer-sized gels were fabricated. Au(0)-nanoparticle-loaded gels were obtained by adsorbing Au(III) ions onto the gels, followed by the reduction of the adsorbed ions. All the Au(0)-nanoparticle-loaded gels successfully functioned as catalysts for the reduction of p-nitrophenol to p-aminophenol with NaBH4. The catalytic performance of the gels was evaluated using the pseudo-first-order reaction rate constant and apparent activation energy. The polymer type and the DMAA gel composition had little effect on the apparent reaction rate constant. The kinetic rate-determining steps in the Au(0)-nanoparticle-loaded gels with various diameters were identified using the Weisz-Prater modulus and the effectiveness factor, and the concentration profile of the reactant in the gels were estimated.
2021年12月, 研究論文（学術雑誌）, 共同, 54, 12, 0021-9592, DOI(公開)(r-map), 648, 656 - Plasma Graft Polymerization and Surface-Initiated Atom Transfer Radical Polymerization: Characteristics of Low-Fouling Membranes Obtained by Surface Modification with Poly(2-methoxyethyl Acrylate)
Akamatsu, Kazuki; Saito, Tatsuru; Ohashi, Hidenori; Wang, Xiao-lin; Nakao, Shin-ichi
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
AMER CHEMICAL SOC
This study investigated the characteristics of membranes modified by grafting poly(2-methoxyethyl acrylate) (PMEA) onto their surfaces and pore walls via plasma graft polymerization (PGP) and surface-initiated atom transfer radical polymerization (SI-ATRP) to render the membrane surfaces fouling-free. The grafting of PMEA was successfully achieved using both methods. Although no remarkable differences were observed in the modified membranes through structural analyses such as FT-IR and FE-SEM, pure water permeability was higher in the membranes modified by SI-ATRP than in those modified by PGP, particularly at the same grafting amount. This was probably because the length of the grafted PMEA was shorter with a higher PMEA density per surface area when SI-ATRP was employed for the modification with PMEA, compared to those obtained when PGP was used. The modified membranes exhibited excellent low-fouling properties against bovine serum albumin (BSA), regardless of the modification method used. In addition, it was demonstrated that the low-fouling properties resulted from the suppression of BSA adsorption by the grafted PMEA. Finally, no flux decline was demonstrated through a 10 h filtration test of raw water for water supply with the modified membranes, which clearly indicated the effective fouling suppression performance of the modified membranes.
2021年10月27日, 研究論文（学術雑誌）, 共同, 60, 42, 0888-5885, DOI(公開)(r-map), 15248, 15255 - Suitable acid groups and density in electrolytes to facilitate proton conduction
Ogawa, Takaya; Ohashi, Hidenori; Anilkumar, Gopinathan M.; Tamaki, Takanori; Yamaguchi, Takeo
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
ROYAL SOC CHEMISTRY
Proton conducting materials suffer from low proton conductivity under low-relative humidity (RH) conditions. Previously, it was reported that acid-acid interactions, where acids interact with each other at close distances, can facilitate proton conduction without water movement and are promising for overcoming this drawback [T. Ogawa, H. Ohashi, T. Tamaki and T. Yamaguchi, Chem. Phys. Lett., 2019, 731, 136627]. However, acid groups have not been compared to find a suitable acid group and density for the interaction, which is important to experimentally synthesize the material. Here, we performed ab initio calculations to identify acid groups and acid densities as a polymer design that effectively causes acid-acid interactions. The evaluation method employed parameters based on several different optimized coordination interactions of acids and water molecules. The results show that the order of the abilities of polymer electrolytes to readily induce acid-acid interactions is hydrocarbon-based phosphonated polymers > phosphonated aromatic hydrocarbon polymers > perfluorosulfonic acid polymers approximate to perfluorophosphonic acid polymers > sulfonated aromatic hydrocarbon polymers. The acid-acid interaction becomes stronger as the distance between acids decreases. The preferable distance between phosphonate moieties is within 13 angstrom.
2021年10月27日, 研究論文（学術雑誌）, 共同, 23, 41, 1463-9076, DOI(公開)(r-map), 23778, 23786 - Quick Refolding of High-Concentration Proteins via Microchannel Dialysis
Kato, Aoi; Ohashi, Hidenori
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
AMER CHEMICAL SOC
The industrial production of active proteins from Escherichia coli necessitates the refolding of high concentrations of protein over a short period of time. However, it is difficult to simultaneously achieve high concentration and short operation time. In the present study, by designing microchannels with dialysis membranes by a chemical engineering way, the surface area was enlarged for quickly removing the protein denaturant and high-concentration protein refolding was achieved in a short time; high concentrations of active carbonic anhydrase-8 times more concentrated than achieved using dilution method-were refolded in 20 min, which is orders of magnitude faster than the conventional dialysis method.
2021年07月21日, 研究論文（学術雑誌）, 共同, 60, 28, 0888-5885, DOI(公開)(r-map), 10076, 10082 - Inhibition of Agrobacterium tumefaciens biofilm formation by acylase I-immobilized polymer surface grafting of a zwitterionic group-containing polymer brush
Bao, Qian; Xie, Li; Ohashi, Hidenori; Hosomi, Masaaki; Terada, Akihiko
BIOCHEMICAL ENGINEERING JOURNAL
ELSEVIER
Membrane processes for water purification and wastewater treatment are impacted by biofilm formation, a hotspot for bacterial cell-cell communication, mainly mediated by N-acyl homoserine lactones (AHLs) as signal compounds. Polymer materials for membrane filtration require high water permeability and biofilm deterrents. Therefore, in this study, a hydrophilic and enzyme-immobilizing polymer membrane was designed, for the first time, to prevent biofilm formation by degrading AHLs. A polyethylene membrane (PE) sheet was grafted as a substratum with glycidyl methacrylate (GMA) by radiation-induced graft polymerization (RIGP). The epoxy group in GMA was further converted into dimethylamino-gamma-butyric acid (DMGABA) to increase hydrophilicity. To prevent biofilm formation by cell-cell communication, the quorum-quenching enzyme, acylase I, with or without activity was immobilized onto a DMGABA membrane sheet, providing enzymatically active DMGABA (EI-DMGABA) and inactive DMGABA (Ina-EI-DMGABA) sheets, respectively. The introduction of DMGABA improved hydrophilicity with a static contact angle of 30.2 degrees, as compared to GMA (84.3 degrees). In a flow cell biofilm formation experiment, biofilm formation of Agrobacterium tumefaciens, using AHLs for quorum sensing, was dramatically inhibited on an EI-DMGABA sheet, but not on an Ina-EI-DMGABA sheet. The successful result to prove the concept of active AHL-degrading enzyme immobilized onto a hydrophilic polymer surface likely paves the way for the application to inhibition of unfavorable biofilm formation onto an interface.
2019年12月15日, 研究論文（学術雑誌）, 共同, 152, 1369-703X, DOI(公開)(r-map), 107372 - Autonomous Shrinking/Swelling Phenomenon Driven By Macromolecular Interchain Cross-Linking via beta-Cyclodextrin-Triazole Complexation
Sugawara, Yuuki; Takei, Toshiki; Ohashi, Hidenori; Kuroki, Hidenori; Miyanishi, Shoji; Yamaguchi, Takeo
MACROMOLECULES
AMER CHEMICAL SOC
Molecular recognition-induced autonomous dynamic motions, which feature in living systems, have been attracting much interest because such biological functions can promote the consequent development of sophisticated functional materials. To realize molecular recognition-induced autonomous dynamic motions using synthetic materials and manipulate them, herein, we designed poly(NIPAM-co-triaz-CD), which bears a cyclodextrin (CD) host and a triazole guest in the side chains of the polymer itself; subsequently, we investigated its phase transition behavior. 2D NOESY NMR analysis evidenced that triazole in the polymer side chains was included into the CD cavity, and DLS measurements indicated that the CD triazole complexation resulted in the formation of interchain cross-linking. Poly(NIPAM-co-triaz CD) exhibited autonomous shrinking/swelling of the polymer chains that occurred by itself in water due to the interchain cross-linking via the CD triazole complexation. Thus, this study enabled the poly(NIPAM) itself to generate the artificial molecular recognition-induced autonomous phenomenon. These findings not only present a unique methodology for polymer phase transition phenomena but also provide a new platform for designing molecular recognition polymeric materials.
2019年11月26日, 研究論文（学術雑誌）, 共同, 52, 22, 0024-9297, DOI(公開)(r-map), 8551, 8562 - Proton diffusion facilitated by indirect interactions between proton donors through several hydrogen bonds
Ogawa, Takaya; Ohashi, Hidenori; Tamaki, Takanori; Yamaguchi, Takeo
CHEMICAL PHYSICS LETTERS
ELSEVIER
The packed-acid mechanism has been recently proposed as a proton conduction mechanism in environments with a high concentration of proton donors, whereby protons are conducted via acid-acid interaction. The acid-acid interaction was originally stated to occur only when a hydrogen bond (H-bond) is formed directly between proton donors. This study clarifies that proton donors can indirectly interact with each other through several H-bonds, even when the donors are separated distantly (indirect acid-acid interactions). Ab initio calculations confirmed that indirect interaction make a non-negligible contribution to proton diffusivity.
2019年09月16日, 研究論文（学術雑誌）, 共同, 731, 0009-2614, DOI(公開)(r-map), 136627 - Performance analysis of a water-gas shift membrane reactor for integrated coal gasification combined cycle plant
Yonamine, Wataru; Thangavel, Sivasakthivel; Ohashi, Hidenori; Fushimi, Chihiro
ENERGY CONVERSION AND MANAGEMENT
PERGAMON-ELSEVIER SCIENCE LTD
In integrated gasification combined cycle (IGCC) systems, the water-gas shift reaction, which promotes the conversion of CO present in syngas mixtures into hydrogen, is an important step for hydrogen production. Application of the water-gas shift membrane reactor (WGSMR) in IGCC systems is an attractive option for CO2 capture compared with conventional methods because of smaller heat loss in gas purification and high CO conversion by selectively removing hydrogen from the reaction zone through the membrane. In this study, we proposed and evaluated commercial-scale WGSMR models combined with IGCC using reported laboratory-scale experimental data to optimize their operational parameters. Various models were developed using the Aspen Plus (R) Ver. 8.6 process simulator to investigate the impacts of hydrogen separation, pressure loss, and the flow direction between the sweep gas on the permeate side and syngas on the retentate side on the WGSMR performance with respect to CO conversion, H-2 yield, and reactor temperature. The membrane reactor model gave approximately 20% higher CO conversion than a reactor model without H-2 separation and approximately 4% lower CO conversion than a membrane reactor model with a pressure drop. A counter-current membrane reactor model gave approximately 2% higher CO conversion than a co-current model; the H-2 yield on the permeate side was 9.3% higher in the counter-current model by separation of H-2 through the membrane. A sensitivity analysis indicated that a high flow rate and low pressure of sweep gas are advantageous for H-2 recovery, and high catalyst loading and high syngas inlet temperature are preferable for higher CO conversion.
2018年10月15日, 研究論文（学術雑誌）, 共同, 174, 0196-8904, DOI(公開)(r-map), 552, 564 - Immobilization of Azospira sp strain I13 by gel entrapment for mitigation of N2O from biological wastewater treatment plants: Biokinetic characterization and modeling
Suenaga, Toshikazu; Aoyagi, Ryo; Sakamoto, Nozomi; Riya, Shohei; Ohashi, Hidenori; Hosomi, Masaaki; Tokuyama, Hideaki; Terada, Akihiko
JOURNAL OF BIOSCIENCE AND BIOENGINEERING
SOC BIOSCIENCE BIOENGINEERING JAPAN
Development of a strategy to mitigate nitrous oxide (N2O) emitted from biological sources is important in the nexus of wastewater treatment and greenhouse gas emission. To this end, immobilization of N2O-reducing bacteria as a biofilm has the potential to ameliorate oxygen (O-2) inhibition of the metabolic activity of the bacteria. We demonstrated the effectiveness of calcium alginate gel entrapment of the nosZ Glade II type N2O-reducing bacterium, Azospira sp. strain I13, in reducing levels of N2O, irrespective of the presence of O-2 . Azospira sp. strain I13 cells in the gel exhibited N2O reduction up to a maximum dissolved oxygen concentration of 100 mu M in the bulk liquid. The maximum apparent N2O uptake rate,& nbsp; V'(m,N2O), by gel immobilization did not appreciably decrease, retaining 72% of the N2O reduction rate of the cell suspension of Azospira sp. strain I13. Whereas gel immobilization increased the apparent half-saturation constant for N2O, K'(m,N2O ), and the apparent O-2 inhibition constant, K'(1,O2) , representing the degree of O-2 resistance, correspondingly increased. A mechanistic model introducing diffusion and the reactions of N2O consumption was used to describe the experimental observations. Incorporating Thieles modulus into the model determined an appropriate gel size to achieve N2O reduction even under aerobic conditions. (C) 2018, The Society for Biotechnology, Japan. All rights reserved.
2018年08月, 研究論文（学術雑誌）, 共同, 126, 2, 1389-1723, DOI(公開)(r-map), 213, 219 - Alkali-resistant Anion Exchange Membranes with Grafted Polyelectrolyte for Fuel Cells
Ohashi, Hidenori; Jung, Hyangmi; Chi, Xueqin; Miyanishi, Shoji; Yamaguchi, Takeo
CHEMISTRY LETTERS
CHEMICAL SOC JAPAN
Pore-filling anion exchange membranes for use in fuel cell applications are fabricated by grafting anion exchange polymers onto pore surfaces of a porous substrate. Because grafted polymers are tethered, the membranes realize high stabilities against hydroxide ions and sufficient hydroxide ion conductivities as well. The grafting strategy is consistent with the existing strategy of molecular structure design to improve the membrane alkali stability.
2018年07月, 研究論文（学術雑誌）, 共同, 47, 7, 0366-7022, DOI(公開)(r-map), 857, 859 - Control of Target Molecular Recognition in a Small Pore Space with Biomolecule-Recognition Gating Membrane
Okuyama, Hiroto; Oshiba, Yuhei; Ohashi, Hidenori; Yamaguchi, Takeo
SMALL
WILEY-V C H VERLAG GMBH
A biomolecule-recognition gating membrane, which introduces thermosensitive graft polymer including molecular recognition receptor into porous membrane substrate, can close its pores by recognizing target biomolecule. The present study reports strategies for improving both versatility and sensitivity of the gating membrane. First, the membrane is fabricated by introducing the receptor via a selectively reactive click reaction improving the versatility. Second, the sensitivity of the membrane is enhanced via an active delivering method of the target molecules into the pores. In the method, the tiny signal of the target biomolecule is amplified as obvious pressure change. Furthermore, this offers 15 times higher sensitivity compared to the previously reported passive delivering method (membrane immersion to sample solution) with significantly shorter recognition time. The improvement will aid in applying the gating membrane to membrane sensors in medical fields.
2018年05月03日, 研究論文（学術雑誌）, 共同, 14, 18, 1613-6810, DOI(公開)(r-map) - Control of Target Molecular Recognition in a Small Pore Space with Biomolecule-Recognition Gating Membrane
Hiroto Okuyama, Yuhei Oshiba, Hidenori Ohashi, and Takeo Yamaguchi
Small
2017年12月, 研究論文（学術雑誌）, 共同, 1702267, DOI(公開)(r-map), 1, 5 - In-plane and through-plane non-uniform carbon corrosion of polymer electrolyte fuel cell cathode catalyst layer during extended potential cycles
Ghosh, Sourov; Ohashi, Hidenori; Tabata, Hiroshi; Hashimasa, Yoshiyuki; Yamaguchi, Takeo
JOURNAL OF POWER SOURCES
ELSEVIER SCIENCE BV
The impact of electrochemical carbon corrosion via potential cycling durability tests mimicking start stop operation events on the microstructure of the cathode catalyst layer in polymer electrolyte fuel cells (PEFCs) is investigated using focused ion beam (FIB) fabrication without/with the pore-filling technique and subsequent scanning electron microscope (SEM) observations. FIB/SEM investigations without pore-filling reveals that the durability test induces non-uniform cathode shrinking across the in plane direction; the thickness of the catalyst layer decreases more under the gas flow channel compared to the area under the rim of the flow field. Furthermore, FIB/SEM investigations with the pore-filling technique reveal that the durability test also induces non-uniform cathode shrinking in the through plane direction; the pores in the area close to the membrane are more shrunken compared with those close to the microporous layer. In particular, a thin area (1-1.5 mu m) close to the membrane is found to be severely damaged; it includes closed pores that hinder mass transport through the catalyst layer. It is suggested that uneven carbon corrosion and catalyst layer compaction are responsible for the performance loss during potential cycling operation of PEFCs. (C) 2017 Elsevier B.V. All rights reserved.
2017年09月, 研究論文（学術雑誌）, 共同, 362, 0378-7753, DOI(公開)(r-map), 291, 298 - Non-equilibrium Thermodynamic Model of a Highly Permeable Forward Osmosis Membrane
Amamiya, Seiichi; Ohashi, Hidenori; Yamaguchi, Takeo
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
SOC CHEMICAL ENG JAPAN
Forward osmosis (FO) membranes with high water permeation flux are required for FO processes to overcome reverse osmosis energy efficiency and translate the FO process into practical applications. However, in the case of such membranes, convective solute transport has a profound effect on solute permeation flux. The existing solution-diffusion model ignores the convection term and the solute permeation flux cannot be accurately analyzed. To solve this problem, the FO membrane permeation was theoretically modeled via non-equilibrium thermodynamics to introduce the convection effect and by coupling with both the internal and external concentration polarizations. First, the FO desalination process (feed solution was sea water (3.3 wt% NaCl aq.)) was investigated by the model. By slightly decreasing the reflection coefficient, which had minimal influence on water permeation flux, both the convective salt transport and NaCl permeation flux increased significantly. Second, a simplified model system (the feed solution was pure water and the draw solution was NaCl aq.) for the wastewater treatment FO process was analyzed. In this system, water permeated in a direction opposite to that of NaCl, and relevant complex behavior of salt permeation was observed.
2017年08月, 研究論文（学術雑誌）, 共同, 50, 8, 0021-9592, DOI(公開)(r-map), 618, 631 - Correlation between the Activity and Molecular Structure around the Active Center of Cytochrome P450cam Conjugates
Yuhei Oshiba, Takanori Tamaki, Hidenori Ohashi, Hidehiko Hirakawa, Satoshi Yamaguchi, Teruyuki Nagamune, and Takeo Yamaguchi
Journal of Chemical Engineering of Japan
2016年05月, 研究論文（学術雑誌）, 共同, 49, 5, DOI(公開)(r-map), 475, 480 - Quantum Chemical Approach for Highly Durable Anion Exchange Groups in Solid-state Alkaline Fuel Cells
Keitaro Matsuyama, Hidenori Ohashi, Shoji Miyanishi, Hiroshi Ushiyama, and Takeo Yamaguchi
RSC Advances
2016年04月, 研究論文（学術雑誌）, 共同, 6, 43, DOI(公開)(r-map), 36269, 36272
研究発表、招待講演等
- 表面開始グラフト重合の機能膜への応用
2022年度膜工学春季講演会・膜工学サロン
2023年03月29日, 口頭発表（招待・特別） - 磁場駆動型正浸透濃縮プロセスの提案
化学工学会第88年会
2023年03月17日, ポスター発表 - 水酸化物イオンを含む深共晶溶媒を用いた空気アルミニウム二次電池の開発
第25回化学工学会学生発表会
2023年03月09日, 口頭発表（一般） - 無機素材への大気圧プラズマグラフト重合法の開発
第25回化学工学会学生発表会
2023年03月09日, 口頭発表（一般） - 多孔質ポリイミド膜を用いた有機溶媒逆浸透膜の開発
日本膜学会第44年会
2022年06月09日, ポスター発表 - VRFBにおける容量損失の機構解明および低減のための価数選択型電解質膜の開発
化学工学会第87年会
2022年03月18日, ポスター発表 - 高分子溶液の系統的粘弾性測定による自由体積の研究
化学工学会第87年会
2022年03月18日, ポスター発表 - 大気圧プラズマグラフト重合法の基礎的検討とその応用
化学工学会第86年会
2021年03月20日, ポスター発表 - グラファイトの表面微量酸官能基の定量
化学工学会第86年会
2021年03月20日, ポスター発表 - 高分子溶液の粘弾性測定を用いた分子拡散性予測
膜シンポジウム2020
2020年11月12日, ポスター発表 - バナジウムレドックスフロー電池用の価数選択型電解質膜の開発
膜学会第42年会
2020年06月01日, ポスター発表 - 高分子中の分子拡散性予測における自由体積の加成性に関する議論
膜学会第42年会
2020年06月01日, ポスター発表 - マイクロ流路型高比表面積圧透析によるタンパク質高速濃縮
化学工学会第85年会
2020年03月15日, ポスター発表 - グラファイトの気相修飾によるLIBの高温保存性能向上
化学工学会第85年会
2020年03月15日, ポスター発表 - 高濃度活性タンパク質の高速製造法の開発
膜シンポジウム2019
2019年11月11日, ポスター発表 - Quick Refolding of High Concentration Protein via Microchannel Flow Dialysis
18th Asian Pacific Confederation of Chemical Engineering Congress (APCChE 2019)
2019年09月23日, 口頭発表（一般） - 移動物性を基盤としたデバイス・システム設計
化学工学会 第50回秋季大会
2018年09月18日, シンポジウム・ワークショップ パネル（指名） - A Prediction Model for Molecular Diffusivity in Polymeric Systems and Application for Coating Processes
9th Asia Coating Workshop
2017年05月27日, 口頭発表（招待・特別）