研究者詳細 - 山口　毅

論文 - 山口　毅

分割表示 135 件中 21 - 40 件目／全件表示 >>

Development of a solvent-polarizable three-dimensional reference interaction-site model theory 査読有り

Norio Yoshida, Tsuyoshi Yamaguchi

Journal of Chemical Physics 152 巻 ( 11 ) 頁： 114108 2020年3月

Carbon Dioxide Absorption Heat in Liquid-Liquid and Solid-Liquid Phase-Change Solvents Using Continuous Calorimetry 査読有り

Tran Khuyen V. B., Ando Ryuya, Yamaguchi Tsuyoshi, Machida Hiroshi, Norinaga Koyo

INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH 59 巻 ( 8 ) 頁： 3475 - 3484 2020年2月

Dynamic Chelate Effect on the Li+-Ion Conduction in Solvate Ionic Liquids 査読有り

Arai Nana, Watanabe Hikari, Yamaguchi Tsuyoshi, Seki Shiro, Ueno Kazuhide, Dokko Kaoru, Watanabe Masayoshi, Kameda Yasuo, Buchner Richard, Umebayashi Yasuhiro

JOURNAL OF PHYSICAL CHEMISTRY C 123 巻 ( 50 ) 頁： 30228 - 30233 2019年12月

Modelling of CO2 solubility in phase separation solvent composed of amine/ether/water system for CO2 capture 査読有り

Machida Hiroshi, Ando Ryuya, Esaki Takehiro, Yamaguchi Tsuyoshi, Norinaga Koyo

JOURNAL OF MOLECULAR LIQUIDS 292 巻 2019年10月

Composition Dependence of Translation-Orientation Coupling Constant in the Mixture of n-pentane and 2,2-dimethylpropane Studied by Molecular Dynamics Simulation 査読有り

Matsuoka Tatsuro, Yatsuya Masaki, Yamaguchi Tsuyoshi

JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 88 巻 ( 9 ) 2019年9月

Effect of Molecular Orientational Correlations on Solvation Free Energy Computed by Reference Interaction Site Model Theory 査読有り

Tanimoto Shoichi, Yoshida Norio, Yamaguchi Tsuyoshi, Ten-no Seiichiro L., Nakano Haruyuki

JOURNAL OF CHEMICAL INFORMATION AND MODELING 59 巻 ( 9 ) 頁： 3770 - 3781 2019年9月

Relation between Anharmonicity of Free-Energy Profile and Spectroscopy in Solvation Dynamics: Differences in Spectral Broadening and Peak Shift in Transient Hole-Burning Spectroscopy Studied by Equilibrium Molecular Dynamics Simulation 査読有り

Yamaguchi Tsuyoshi, Yoshida Norio, Nishiyama Katsura

JOURNAL OF PHYSICAL CHEMISTRY B 123 巻 ( 32 ) 頁： 7036 - 7042 2019年8月

Shear Thinning and Nonlinear Structural Deformation of Ionic Liquids with Long Alkyl Chains Studied by Molecular Dynamics Simulation 査読有り

Yamaguchi Tsuyoshi

JOURNAL OF PHYSICAL CHEMISTRY B 123 巻 ( 29 ) 頁： 6260 - 6265 2019年7月

High-frequency shear viscosity and ionic mobility of solutions of polyethylene glycol in ionic liquids

Yamaguchi Tsuyoshi, Kikuzawa Takujiro

JOURNAL OF MOLECULAR LIQUIDS 284 巻頁： 252 - 257 2019年6月

Collective Mesoscale Dynamics of Liquid 1-Dodecanol Studied by Neutron Spin-Echo Spectroscopy with Isotopic Substitution and Molecular Dynamics Simulation 査読有り国際共著

Yamaguchi Tsuyoshi, Faraone Antonio, Nagao Michihiro

JOURNAL OF PHYSICAL CHEMISTRY B 123 巻 ( 1 ) 頁： 239 - 246 2019年1月

Degradation Test for Energy-Saving CO<inf>2</inf> Absorbent based on Phase Separation Type Solvent by Aqueous (Amine + Ether) Solution

Maeda N., Kishimoto A., Machida H., Yamaguchi T.

GHGT 2018 - 14th International Conference on Greenhouse Gas Control Technologies 2018年

出版者・発行元：GHGT 2018 - 14th International Conference on Greenhouse Gas Control Technologies

The unique phase separation type amine/ether absorbent is expected to realize the CO2 separation process with low-energy consumption (1.5GJ/ton-CO2). In this study, a degradation test of the absorbent under thermal load of liquid regeneration was conducted in order to clarify 1) the behavior of its performance declination for CO2 capture and 2) the behavior of amine loss mainly caused by generation of by-product. The regeneration condition was chosen based on two assumptions that a) most likely to damage to the solution, which means high-oxidation atmosphere containing oxygen and sulfur oxide, and b) adopting actual operating temperature when absorbing or desorbing. As a result, only a small amount of the CO2 capture capability was lost through 48 hours cyclic thermal load of 50-90 °C. Consequently, it was found that the phase separation type solvent could be durable enough for the practical use. Besides, the running cost associated with make-up amine might be drastically reduced.

Scopus

Energy-saving CO<inf>2</inf> Capture Process Using Phase Separation Type Solvent by Aqueous (amine + ether) Solution

Machida H., Takehiro E., Yamaguchi T., Norinaga K., Kishimoto A., Akiyama K., Nishimura M.

GHGT 2018 - 14th International Conference on Greenhouse Gas Control Technologies 2018年

出版者・発行元：GHGT 2018 - 14th International Conference on Greenhouse Gas Control Technologies

We have developed the phase separation solvent for CO2 capture. Our developed solvent consists amine, organic solvent and water and shows single liquid phase before CO2 absorption though it shows two liquid phases after CO2 absorption. Feature of phase separation solvent is reducing temperature difference between absorber and stripper. We apply the heat pump system for CO2 separation and evaluate the energy consumption. Low temperature swing process saves energy requirement for CO2 capture process with highly-effective reaction-heat recovering. To evaluate the CO2 capture system with our solvent, screening test for amine and organic solvent combination and CO2 solubility measurement were examined. In the phase separation test, three types of solvents were obtained by combining amine and ether, that is, no phase separation with CO2 scrubbing, phase separation with CO2 scrubbing, and thoroughly immiscible. The phase behaviour depends on the hydrophobicity of amines or organic solvents, and the types of solvents were classified using the hydrophobic parameter.

Scopus

Development of phase separation solvent for CO2 capture by aqueous (amine plus ether) solution

Machida Hiroshi, Oba Kazuki, Tomikawa Takashi, Esaki Takehiro, Yamaguchi Tsuyoshi, Horizoe Hirotoshi

JOURNAL OF CHEMICAL THERMODYNAMICS 113 巻頁： 64 - 70 2017年10月

A method for protein structure sampling under three-dimensional reference interaction site model solvation based on hybrid Monte Carlo framework 査読有り

Yoshida Norio, Yamaguchi Tsuyoshi

JOURNAL OF MOLECULAR LIQUIDS 385 巻 2023年9月

担当区分：最終著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Molecular Liquids

An efficient sampling method for protein structure using molecular dynamics (MD) simulation and a three-dimensional reference interaction-site model (3D-RISM) theory has been developed based on the hybrid Monte Carlo framework. In this method, new structures are generated by MD simulation with the generalized Born implicit solvent model and the Metropolis-like criterion to accept or reject the structure candidate is applied based on the free energy corresponding to the 3D-RISM Hamiltonian at each specified time propagation interval. The resulting ensemble of structures satisfies the 3D-RISM Hamiltonian-based equilibrium distribution. The method was applied to alanine dipeptide and methionine-enkephalin polypeptides in aqueous solution as test cases. The results demonstrated the efficiency of the method.

DOI： 10.1016/j.molliq.2023.122418

Web of Science

Scopus

Effects of angular momentum and thermostat on molecular dynamics simulation of single-chain conformation in an implicit solvent 査読有り

Yamaguchi Tsuyoshi, Chong Song-Ho, Yoshida Norio

JOURNAL OF MOLECULAR LIQUIDS 385 巻 2023年9月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Molecular Liquids

The effect of angular momentum on single-chain conformation in an implicit solvent model was investigated by molecular dynamics simulation. The distribution of the end-to-end distance depends on whether the angular momentum of the entire molecule is fixed or thermalized, and these two distributions can be transformed from the one to the other through the reweighting method. In addition, depending on the thermostat, the thermalization of the angular momentum becomes insufficient even if no constraint is imposed on the angular momentum, resulting in the distortion of the distribution of chain conformation. These results suggest the importance of the choice of thermostat that enables the thermalization of the angular momentum.

DOI： 10.1016/j.molliq.2023.122311

Web of Science

Scopus

Durability and fire-hazardous-risk evaluation of unique phase separation solvent using high-boiling-point amine and ether 査読有り

Maeda N., Kishimoto A., Machida H., Yamaguchi T., Yanase K., Norinaga K.

International Journal of Greenhouse Gas Control 114 巻 2022年2月

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 Greenhouse Gas Control

Durability and fire hazard risk evaluations were conducted to determine the process feasibility of a unique phase separation solvent with a low regeneration temperature (90 °C) consisting of an amine, ether, and a small amount of water. The results are as follows. I) The amine degradation rate of the phase separation solvent was determined to be less than 1/10 of that of monoethanolamine, which was attributed to the high oxidative resistance and low regeneration temperature of the former. II) The composition of the gas that formed in the absorber was completely out of the combustible range during the treatment of 6% oxygen-containing gas on a dry basis. Therefore, we believe that this phase separation solvent is applicable to the treatment of exhaust gas from coal-fired thermal power plants and can realize stable operation with a small amount of amine required for replenishment.

DOI： 10.1016/j.ijggc.2021.103532

Scopus

Fluctuation in diethylene glycol diethyl ether/water mixtures near the lower critical solution temperature studied by small- and wide-angle x-ray scattering and thermodynamic calculation 査読有り

Yanase K., Tran K.V.B., Yamaguchi T., Machida H., Norinaga K.

Journal of Molecular Liquids 346 巻 2022年1月

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 Molecular Liquids

We studied local structure of diethylene glycol diethyl ether (DEGDEE)-water mixtures near the lower critical solution temperature (LCST) by means of simultaneous small- and wide-angle x-ray scattering measurement and thermodynamic calculation based on the activity coefficient model. Long-wavelength limits of structure factors SNN(0), SCC(0), and SNC(0), which respectively represent mean square fluctuations in the particle number, the concentration, and their cross correlation, are determined from scattering intensity extrapolated to the zero scattering vector and thermodynamic quantities according to the Bhatia and Thornton formula. SNN(0) and SCC(0) exhibit maxima near critical concentration. We found that difference between partial molar volumes of water and DEGDEE essentially results in SNN(0) values being one order of magnitude larger than SCC(0) values. Further, we determined Kirkwood-Buff (KB) integrals to clarify a mixing state of the solution from a mesoscopic point of view. The KB integrals also exhibit extrema near critical concentration. These results demonstrate self-segregations of both DEGDEE and water in a nanometer length scale even at homogeneous solution states, which can be regarded as a precursor of the macroscopic phase separation. Concentration dependence of the wide-angle scattering curve suggests that the short-range structure, whose length scale is sub-nanometer, moderately changes between the intrinsic bulk structures of DEGDEE and water. Comparison of the KB integrals with those determined by the activity coefficient model using non-random two-liquid equation is presented and effects of the fluctuation on the phase behavior are discussed.

DOI： 10.1016/j.molliq.2021.117830

Scopus

Momentum removal to obtain the position-dependent diffusion constant in constrained molecular dynamics simulation 査読有り

Fujimoto Kazushi, Nagai Tetsuro, Yamaguchi Tsuyoshi

JOURNAL OF COMPUTATIONAL CHEMISTRY 42 巻 ( 30 ) 頁： 2136 - 2144 2021年8月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Computational Chemistry

The position-dependent diffusion coefficient along with free energy profile are important parameters needed to study mass transport in heterogeneous systems such as biological and polymer membranes, and molecular dynamics (MD) calculation is a popular tool to obtain them. Among many methodologies, the Marrink–Berendsen (MB) method is often employed to calculate the position-dependent diffusion coefficient, in which the autocorrelation function of the force on a fixed molecule is related to the friction on the molecule. However, the diffusion coefficient is shown to be affected by the period of the removal of the center-of-mass velocity, (Formula presented.), which is necessary when performing MD calculations using the Ewald method for Coulombic interaction. We have clarified theoretically in this study how this operation affects the diffusion coefficient calculated by the MB method, and the theoretical predictions are proven by MD calculations. Therefore, we succeeded in providing guidance on how to select an appropriate (Formula presented.) value in estimating the position-dependent diffusion coefficient by the MB method. This guideline is applicable also to the Woolf–Roux method.

DOI： 10.1002/jcc.26742

Web of Science

Scopus

PubMed

Density and Viscosity Calculation of a Quaternary System of Amine Absorbents before and after Carbon Dioxide Absorption 査読有り

Khuyen Viet Bao Tran, Sato Miho, Yanase Keiichi, Yamaguchi Tsuyoshi, Machida Hiroshi, Norinaga Koyo

JOURNAL OF CHEMICAL AND ENGINEERING DATA 66 巻 ( 8 ) 頁： 3057 - 3071 2021年8月

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 Chemical and Engineering Data

Viscosity and density of amine absorbents affect directly their flow, which is involved in the process design and simulation of carbon dioxide capture. A mixture of 2-(ethyl amino) ethanol (EAE), diethylene glycol diethyl ether (DEGDEE), and water changes its phase from homogeneous to two-liquid ones on CO2 absorption. It is difficult to calculate the viscosity and density of this phase separation solution, especially those of quaternary-component phases. In this research, models to calculate the density and viscosity of the quaternary-component system of EAE/DEGDEE/water/carbamate were suggested based on nonrandom two-liquid (NRTL)-DVOL and NRTL-DVIS models. Given the component concentrations, these models can replicate well the viscosity and density of the solutions. A good calculation result with a few numbers of parameters makes the models simple and easy to use.

DOI： 10.1021/acs.jced.1c00195

Web of Science

Scopus

Online composition analysis of phase separation solvent for carbon dioxide capture using ATR‐FT‐IR 査読有り

Miho Sato, Khuyen Viet Bao Tran, Tsuyoshi Yamaguchi, Hiroshi Machida, Koyo Norinaga

Journal of Advanced Manufacturing and Processing 2020年10月

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