last update: April 5, 2024


Publication list
 A. Articles - Structure and Thermodynamic Stabilities of Gas Hydrates - (A-1〜A-85)
 B. Article - Crystallization of Phase Change Materials and Thermal Storage- (B-1〜B-21)
 C. Article - Structures of Clathrate Compounds - (C-1〜C-4)
 D. Article - Others - (D-2)
 X. Review Articles in Japanese (X-1〜X-19)
 Y. International Conferences (Y-1〜Y-86)



Articles (peer-reviewed) - Structure and Thermodynamic Stability of Gas Hydrates -

-1999-
A-1) Hysteresis in Dissociation and Reformation of Methane Hydrate Crystal
Kazunari Ohgaki, Takeshi Sugahara and Shinya Nakano
Journal of Chemical Engineering of Japan, 32(2), 235-236 (1999) [DOI]

-2000-
A-2) Border Gas Hydrate System Having Quadruple Point of Hydrate + Two Liquids + Gas Phases
Takeshi Sugahara and Kazunari Ohgaki
Journal of Chemical Engineering of Japan, 33(1), 174-176 (2000) [DOI]

A-3) Phase Behavior of Xenon Hydrate System
Kazunari Ohgaki, Takeshi Sugahara, Masaru Suzuki and Hitoshi Jindai
Fluid Phase Equilibria, 175(1-2), 1-6 (2000) [DOI]

A-4) Stability Boundary and Small Hydrate-Cage Occupancy of Ethylene Hydrate System
Takeshi Sugahara, Kentaro Morita and Kazunari Ohgaki
Chemical Engineering Science, 55(24), 6015-6020 (2000) [DOI]

-2001-
A-5) Pressure Dependence of Small-Cage Occupancy in the Cyclopropane Hydrate System
Masaru Suzuki, Yuuki Tanaka, Takeshi Sugahara and Kazunari Ohgaki
Chemical Engineering Science, 56(6), 2063-2067 (2001) [DOI]

-2002-
A-6) Thermodynamic Stability and Structure of Nitrogen Hydrate Crystal
Keisuke Sugahara, Yuuki Tanaka, Takeshi Sugahara and Kazunari Ohgaki
Journal of Supramolecular Chemistry, 2(4-5), 365-368 (2002)published in 2003 [DOI]

-2003-
A-7) Phase Transition from Structure-H to Structure-I in the Methylcyclohexane + Xenon Hydrate System
Noriyuki Shimada, Keisuke Sugahara, Takeshi Sugahara and Kazunari Ohgaki
Fluid Phase Equilibria, 205(1), 17-23 (2003) [DOI]

A-8) Stability Boundaries of Gas Hydrates Helped by Methane
    -- structure-H Hydrates of Methylcyclohexane and cis-1,2-Dimethylcyclohexane --
Toshiyuki Nakamura, Takashi Makino, Takeshi Sugahara and Kazunari Ohgaki
Chemical Engineering Science, 58, 269-273 (2003) [DOI]

A-9) Isothermal Phase Equilibria for the Methane + Ethylene Mixed Gas Hydrate System
Takeshi Sugahara, Takashi Makino and Kazunari Ohgaki
Fluid Phase Equilibria, 206(1-2), 117-126 (2003) [DOI]

-2004-
A-10) Stability Boundaries of Structure-H Hydrate of cis-1,4-Dimethylcyclohexane Helped by Methane
Toshiyuki Nakamura, Takeshi Sugahara and Kazunari Ohgaki
Journal of Chemical & Engineering Data, 49(1), 99-100 (2004) (web release: October 23, 2003) [DOI]

A-11) Gas Hydration of trans-1,2-Dimethylcyclohexane with Cooperative Assistance of Methane and cis-1,2-Dimethylcyclohexane
Toshiyuki Nakamura, Takashi Makino, Takeshi Sugahara and Kazunari Ohgaki
Chemical Engineering Science, 59(1), 163-165 (2004) [DOI]

A-12) High-Pressure Phase Behavior and Cage Occupancy for the CF4 Hydrate System
Keisuke Sugahara, Masayoshi Yoshida, Takeshi Sugahara and Kazunari Ohgaki
Journal of Chemical & Engineering Data, 49(2), 326-329 (2004) (web release: January 16, 2004) [DOI]

A-13) Thermodynamic Stability of Structure-H Hydrates of Methylcyclopentane and Cyclooctane Helped by Methane
Takashi Makino, Toshiyuki Nakamura,Takeshi Sugahara and Kazunari Ohgaki
Fluid Phase Equilibria, 218(2), 235-238 (2004) [DOI]

-2005-
A-14) Thermodynamic and Raman Spectroscopic Studies of Xe and Kr Hydrates
Keisuke Sugahara,Takeshi Sugahara and Kazunari Ohgaki
Journal of Chemical & Engineering Data, 50(1), 274-277 (2005). (web release: November 26, 2004) [DOI]

A-15) Icosahedron Cage Occupancy of Structure-H Hydrate Helped by Xe - 1,1-, cis-1,2-, trans-1,2-, and cis-1,4- Dimethylcyclohexanes -
Takeshi Sugahara, Tsutomu Hara, Shunsuke Hashimoto and Kazunari Ohgaki
Chemical Engineering Science, 60(6). 1783-1786 (2005) (web release: January 14, 2005) [DOI]

A-16) Large Pressure Depression of Methane Hydrate by Adding 1,1-Dimethylcyclohexane
Tsutomu Hara, Shunsuke Hashimoto, Takeshi Sugahara and Kazunari Ohgaki
Chemical Engineering Science, 60(11), 3117-3119 (2005) (web release: March 3, 2005) [DOI]

A-17) Hydrate Structural Transition Depending on the Composition of Methane + Cyclopropane Mixed Gas Hydrate
Takashi Makino, Makoto Tongu, Takeshi Sugahara and Kazunari Ohgaki
Fluid Phase Equilibria, 233(2), 129-133 (2005) (web release: June 3, 2005) [DOI]

A-18) Phase Equilibria for H2 + CO2 + H2O System Containing Gas Hydrates
Takeshi Sugahara, Shu Murayama, Shunsuke Hashimoto and Kazunari Ohgaki
Fluid Phase Equilibria, 233(2), 190-193 (2005) (web release: June 13, 2005) [DOI]

A-19) Stability Boundaries of Tetrahydrofuran + Water System
Takashi Makino, Takeshi Sugahara and Kazunari Ohgaki
Journal of Chemical & Engineering Data, 50(6), 2058-2060 (2005) (web release: October 11, 2005) [DOI]

A-20) Activation Energy of Methyl Radical Decay in Methane Hydrate
Kei Takeya, Kouhei Nango, Takeshi Sugahara, Kazunari Ohgaki and Atsushi Tani
The Journal of Physical Chemistry B, 109(44), 21086-21088 (2005) (web release: October 18, 2005) [DOI]

-2006-
A-21) Thermodynamic and Raman Spectroscopic Studies on Pressure-Induced Structural Transition of SF6 Hydrate
Keisuke Sugahara, Masayoshi Yoshida, Takeshi Sugahara and Kazunari Ohgaki
Journal of Chemical & Engineering Data, 51(1), 301-304 (2006) (web release: December 15, 2005) [DOI]

A-22) Phase Equilibria for H2 + CO2 + Tetrahydrofuran + Water Mixtures Containing Gas Hydrates
Shunsuke Hashimoto, Shu Murayama, Takeshi Sugahara and Kazunari Ohgaki
Journal of Chemical & Engineering Data, 51(5), 1884-1886 (2006) (web release: July 26, 2006) [DOI]

A-23) Thermodynamic and Raman Spectroscopic Studies on H2 + Tetrahydrofuran + Water and H2 + Tetra-n-Butyl Ammonium Bromide + Water Mixtures Containing Gas Hydrates
Shunsuke Hashimoto, Shu Murayama, Takeshi Sugahara, Hiroshi Sato and Kazunari Ohgaki
Chemical Engineering Science, 61(24), 7884-7888 (2006) (web release: September 23, 2006) [DOI]

-2007-
A-24) Thermodynamic Stability of H2 + Tetrahydrofuran Mixed Gas Hydrate in Non-Stoichiometric Aqueous Solutions
Shunsuke Hashimoto, Takeshi Sugahara, Hiroshi Sato and Kazunari Ohgaki
Journal of Chemical & Engineering Data, 52(2), 517-520 (2007) (web release: January 11, 2007) [DOI]

A-25) Raman Spectroscopic Studies on Methane + Tetrafluoromethane Mixed-Gas Hydrate System
Yuuki Kunita, Takashi Makino, Takeshi Sugahara and Kazunari Ohgaki
Fluid Phase Equilibria, 251(2), 145-148 (2007) (web release: December 12, 2006) [DOI]

A-26) Electron Spin Resonance Study on gamma-Ray-Induced Ethyl Radical in Ethane Hydrate
Kei Takeya, Kouhei Nango, Takeshi Sugahara, Kazunari Ohgaki, Atsushi Tani, Hironori Ito, Michio Okada, Toshio Kasai
Japanese Journal of Applied Physics, 46(5A), 3066-3070 (2007). [Publisher]

A-27) Fundamental Studies for a New H2 Separation Method Using Gas Hydrates
Shunsuke Hashimoto, Shu Murayama, Takeshi Sugahara, Kazunari Ohgaki
Physics and Chemistry of Ice, 209-216 (2007)

A-28) Effects of Large Guest Species on Thermodynamic Properties of Structure-H Hydrates
Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
Physics and Chemistry of Ice, 363-370 (2007)

A-29) ESR Observation of Self-Preservation Effect of Methane Hydrate
Kei Takeya, Kouhei Nango, Takeshi Sugahara, Atsushi Tani, Kazunari Ohgaki
Physics and Chemistry of Ice, 585-591 (2007)

A-30) Electron Spin Resonance Study on γ-Ray-Induced Radical Species in Ethylene Hydrate
Kei Takeya, Takeshi Sugahara, Kazunari Ohgaki, Atsushi Tani
Radiation Measurements, 42(8), 1301-1306 (2007) [DOI]

-2008-
A-31) Thermodynamic Stability of Hydrogen + Tetra-n-Butyl Ammonium Bromide Mixed Gas Hydrate in Nonstoichiometric Aqueous Solutions
Shunsuke Hashimoto, Takeshi Sugahara, Masato Moritoki, Hiroshi Sato, Kazunari Ohgaki
Chemical Engineering Science, 63(4), 1092-1097 (2008) [DOI]

A-32) Hydrogen Transfer from Guest Molecule to Radical in Adjacent Hydrate-Cages
Kazunari Ohgaki, Kentaro Nakatsuji, Kei Takeya, Atsushi Tani and Takeshi Sugahara
Physical Chemistry Chemical Physics, 10(1), 80-82 (2008) {DOI]

A-33) Cage Occupancy of Hydrogen in Carbon Dioxide, Ethane, Cyclopropane, and Propane Hydrates
Takeshi Sugahara, Hiroki Mori, Jun Sakamoto, Shunsuke Hashimoto, Kyohei Ogata and Kazunari Ohgaki
The Open Thermodynamics Journal, 2, 1-6 (2008) [DOI]

A-34) Isothermal Phase Equilibria and Cage Occupancies for CH4 + CHF3 Mixed-Gas Hydrate System
Takashi Makino, Yuuki Kunita, Takeshi Sugahara and Kazunari Ohgaki
The Open Thermodynamics Journal, 2, 17-21 (2008). [DOI]

A-35) Thermodynamic Stability on Mixed Gas Hydrates Containing Hydrogen
Shunsuke Hashimoto, Takeshi Sugahara, Masato Moritoki, Hiroshi Sato and Kazunari Ohgaki
Journal of Physics: Conference Series, 121, 22012-1-5 (2008). [DOI]

A-36) Storage Capacity of Hydrogen in Tetrahydrofuran Hydrate
Kyohei Ogata, Shunsuke Hashimoto, Takeshi Sugahara, Masato Moritoki, Hiroshi Sato and Kazunari Ohgaki
Chemical Engineering Science, 63(23), 5714-5718 (2008). [DOI]

A-37) Thermodynamic and Raman Spectroscopic Studies on Hydrogen + Tetra-n-Butyl Ammonium Fluoride Semi-Clathrate Hydrates
Jun Sakamoto, Shunsuke Hashimoto, Takaaki Tsuda, Takeshi Sugahara,Yoshiro Inoue and Kazunari Ohgaki
Chemical Engineering Science, 63(24), 5789-5794 (2008). [DOI]

A-38) Thermodynamic and Raman Spectroscopic Studies of Ar Hydrate System
Keisuke Sugahara, Ryuji Kaneko, Arata Sasatani, Takeshi Sugahara and Kazunari Ohgaki
The Open Thermodynamics Journal, 2, 95-99 (2008). [DOI]

A-39) Isothermal Phase Equilibria for Methane + Ethane + Water Ternary System Containing Gas Hydrates
Shunsuke Hashimoto, Arata Sasatani, Yuuki Matsui, Takeshi Sugahara and Kazunari Ohgaki
The Open Thermodynamics Journal, 2, 100-105 (2008). [DOI]

-2009-
A-40) Four-Phase Equilibrium Relations of Methane + Methylcyclohexanol Stereoisomer + Water Systems Containing Gas Hydrate
Takashi Makino, Michiko Mori, Yasutaka Mutou, Takeshi Sugahara and Kazunari Ohgaki
Journal of Chemical & Engineering Data, 54(3), 996-999 (2009). [DOI]

A-41) High-Pressure Phase Equilibrium and Raman Spectroscopic Studies on Nitrous Oxide Hydrate System
Takeshi Sugahara, Akira Kawazoe, Keisuke Sugahara and Kazunari Ohgaki
Journal of Chemical & Engineering Data, 54(8), 2301-2303 (2009) [DOI]

A-42) Tetra-n-butylammonium Borohydride Semi-clathrate: A Hybrid Material for Hydrogen Storage
Kyuchul Shin, Yongkwan Kim, Timothy A. Strobel, Pinnelli S.R. Prasad, Takeshi Sugahara, Huen Lee, E. Dendy Sloan, Amadeu K. Sum, Carolyn A. Koh
The Journal of Physical Chemistry A, 113(23), 6415-6418 (2009). [DOI]

A-43) Hydrogen Storage in Double Clathrates with tert-Butylamine
Pinnelli S.R. Prasad, Takeshi Sugahara, Amadeu K. Sum, E. Dendy Sloan, Carolyn A. Koh
The Journal of Physical Chemistry A, 113(24), 6450-6453 (2009). [DOI]

A-44) Isothermal Phase Equilibria and Structural Phase Transition in the Carbon Dioxide + Cyclopropane Mixed-Gas Hydrate System
Takashi Makino, Yoshihiro Ogura, Yuuki Matsui, Takeshi Sugahara, Kazunari Ohgaki
Fluid Phase Equilibria, 284(1), 19-25 (2009). [DOI]

A-45) Storage Capacity of Hydrogen in Tetrahydrothiophene and Furan Clathrate Hydrates
Takaaki Tsuda, Kyohei Ogata, Shunsuke Hashimoto, Takeshi Sugahara, Masato Moritoki, Kazunari Ohgaki
Chemical Engineering Science, 64(19), 4150-4154 (2009). [DOI]

A-46) Structural Transformations of sVI tert-Butylamine Hydrates to sII Binary Hydrates with Methane
Pinnelli S.R. Prasad, Takeshi Sugahara, E. Dendy Sloan, Amadeu K. Sum, Carolyn A. Koh
The Journal of Physical Chemistry A, 113(42), 11311-11315 (2009). [DOI]

A-47) Increasing Hydrogen Storage Capacity Using Tetrahydrofuran
Takeshi Sugahara, Joanna C. Haag, Pinnelli S.R. Prasad, Ashleigh A. Warntjes, E. Dendy Sloan, Amadeu K. Sum, Carolyn A. Koh
Journal of American Chemical Society, 131(41), 14616-14617 (2009). [DOI]

-2010-
A-48) Thermodynamic Stabilities of Tetra-n-Butyl Ammonium Chloride +H2, N2, CH4, CO2, or C2H6 Semi-Clathrate Hydrate Systems
Takashi Makino, Tomoyo Yamamoto, Kento Nagata, Hiromi Sakamoto, Shunsuke Hashimoto, Takeshi Sugahara, Kazunari Ohgaki
Journal of Chemical & Engineering Data, 55(2), 839-841 (2010). [DOI]

A-49) Thermodynamic Properties of Hydrogen + Tetra-n-Butyl Ammonium Bromide Semi-Clathrate Hydrate
Shunsuke Hashimoto, Takaaki Tsuda, Kyohei Ogata, Takeshi Sugahara, Yoshiro Inoue, Kazunari Ohgaki
Journal of Thermodynamics, 2010, Article ID 170819, 5 page (2010). [DOI]

A-50) Storage Capacity of Hydrogen in Gas Hydrates
Takaaki Tsuda, Kyohei Ogata, Shunsuke Hashimoto, Takeshi Sugahara, Hiroshi Sato, Kazunari Ohgaki
Journal of Physics: Conference Series, 215, 012061 1-5 (2010). [DOI]

A-51) Hydrogen Storage in Trimethylamine Hydrate: Thermodynamic Stability and Hydrogen Storage Capacity of Hydrogen + Trimethylamine Mixed Semi-clathrate Hydrate
Kyohei Ogata, Takaaki Tsuda, Shingo Amano, Shunsuke Hashimoto, Takeshi Sugahara, Kazunari Ohgaki
Chemical Engineering Science, 65(5), 1616-1620 (2010). [DOI]

A-52) Isothermal Phase Equilibria for Binary Hydrate Systems of Carbon Dioxide + Ethane and Carbon Dioxide + Tetrafluoromethane
Yuuki Matsui, Yoshihiro Ogura, Hiroshi Miyauchi, Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
Journal of Chemical & Engineering Data, 55(9), 3297-3301 (2010). [DOI]

A-53) Competitive Cage-occupancy of Hydrogen and Argon in Structure-II Hydrates
Shingo Amano, Takaaki Tsuda, Shunsuke Hashimoto, Takeshi Sugahara, Kazunari Ohgaki
Fluid Phase Equilibria, 298(1), 113-116 (2010). [DOI]

A-54) Large-Cage Occupancies of Hydrogen in Binary Clathrate Hydrates Dependent on Pressures and Guest Concentrations
Takeshi Sugahara, Joanna C. Haag, Ashleigh A. Warntjes, Pinnelli S.R. Prasad, E. Dendy Sloan, Amadeu K. Sum, Carolyn A. Koh
Journal of Physical Chemistry C, 114(35), 15218-15222 (2010). [DOI]

-2011-
A-55) Large-Cage Occupancies of Molecular Hydrogen in Binary Clathrate Hydrates Dependent on Pressures
Takeshi Sugahara, Pinnelli S.R. Prasad, E. Dendy Sloan, Amadeu K. Sum, Carolyn A. Koh, Kazunari Ohgaki
Physics and Chemistry of Ice, 2010, 117-125 (2011).

A-56) In-situ Raman Observation on Aqueous solution around Tetra-n-Butyl Ammonium Bromide Semi-Clathrate Hydrate
Motoi Oshima, Shunsuke Hashimoto, Wataru Shimada, Atsushi Tani, Takeshi Sugahara, and Kazunari Ohgaki
Physics and Chemistry of Ice, 2010, 141-146 (2011).

A-57) Raman Spectroscopic Analysis of Mixed Gas Hydrate Crystals
Hiroko Mimachi, Masahiro Takahashi, Toru Iwasaki, Takahiro Kinoshita, Takeshi Sugahara, Hiroshi Sato, and Kazunari Ohgaki
Physics and Chemistry of Ice, 2010, 243-247 (2011).

A-58) Decay Mechanisms of Radiation-Induced Radicals in Sulfur Hexafluoride Clathrate Hydrate
Kenji Takato, Atsushi Tani, Takeshi Sugahara, Kei Takeya, and Kazunari Ohgaki
Physics and Chemistry of Ice, 2010, 261-266 (2011)

A-59) Thermal Stability of Radicals Induced in Xenon Hydrate
Kei Takeya, Atsushi Tani, Takeshi Sugahara, and Kazunari Ohgaki
Physics and Chemistry of Ice, 2010, 267-271 (2011)

A-60) In-situ ESR Observation of Free Radicals in Gas Hydrates under High Pressure
Atsushi Tani, Kenji Takato, Takeshi Sugahara, Kazunari Ohgaki, Kei Takeya
Physics and Chemistry of Ice, 2010, 273-276 (2011)

A-61) Effect of Cyclopentane on Small-Cage Occupancy of Hydrogen in Clathrate Hydrates
Takaaki Tsuda, Shunsuke Hashimoto, Takeshi Sugahara, Kazunari Ohgaki
Physics and Chemistry of Ice, 2010, 277-281 (2011).

A-62) Structural Phase Transitions of Methane+Ethane Mixed-Gas Hydrate Induced by 1,1-Dimethylcyclohexane
Yuuki Matsumoto, Hiroshi Miyauchi, Takashi Makino, Takeshi Sugahara, and Kazunari Ohgaki
Chemical Engineering Science, 66(12), 2672-2676 (2011). [DOI]

A-63) High-Pressure Phase Equilibrium and Raman Spectroscopic Studies on the 1,1-Difluoroethane (HFC-152a) Hydrate System
Takeshi Sugahara, Aki Endo, Hiroshi Miyauchi, Seung An Choi, Yuuki Matsumoto, Kenjiro Yasuda, Shunsuke Hashimoto, Kazunari Ohgaki
Journal of Chemical & Engineering Data, 56(12), 4592-4596 (2011). [DOI]

-2012-
A-64) Thermodynamic Stability of Hydrogen + Tetra-n-butyl Phosphonium Bromide Mixed Semi-clathrate Hydrate
Yuuya Fujisawa, Takaaki Tsuda, Shunsuke Hashimoto, Takeshi Sugahara, Kazunari Ohgaki
Chemical Engineering Science, 68(1), 660-662 (2012). [DOI]

A-65) Isothermal Phase Equilibria for the Xenon+Cyclopropane Mixed-Gas Hydrate System
Takeshi Sugahara, Hiroshi Miyauchi, Sumihiro Suzuki, Yuuki Matsumoto, Kenjiro Yasuda, Takashi Makino, Kazunari Ohgaki
The Journal of Chemical Thermodynamics, 47C, 13-16 (2012). [DOI]

A-66) Isothermal Phase Equilibria for the HFC-32+HFC-134a Mixed-Gas Hydrate System
Hiroshi Miyauchi, Kenjiro Yasuda, Yuuki Matsumoto, Shunsuke Hashimoto, Takeshi Sugahara, Kazunari Ohgaki
The Journal of Chemical Thermodynamics, 47C, 1-5 (2012). [DOI]

A-67) Intermolecular Hydrogen Transfer between Guest Species in Small and Large Cages of Methane+Propane Mixed-Gas Hydrates
Takeshi Sugahara, Yusuke Kobayashi, Atsushi Tani, Tatsuya Inoue, Kazunari Ohgaki
The Journal of Physical Chemistry A, 116(10), 2405-2408 (2012). [DOI]

A-68) Intermolecular Hydrogen Transfer in Isobutane Hydrate
Naohiro Kobayashi, Takashi Minami, Atsushi Tani, Mikio Nakagoshi, Takeshi Sugahara, Kei Takeya, Kazunari Ohgaki
Energies, 5(6), 1705-1712 (2012). [DOI]

-2013-
A-69) Isothermal Phase Equilibria for the CO2+1,1,1,2-Tetrafluoroethane and CO2+1,1-Difluoroethane Mixed-Gas Hydrate Systems
Sumihiro Suzuki, Kenjiro Yasuda, Yoshito Katsuta, Yuuki Matsumoto, Shunsuke Hashimoto, Takeshi Sugahara, Kazunari Ohgaki
Journal of Chemical & Engineering Data, 58(3), 780-784 (2013). [DOI]

A-70) Phase Equilibrium Relations and Structural Transition in the 1,1,1,2-Tetrafluoroethane Hydrate System
Yoshito Katsuta, Sumihiro Suzuki, Yuuki Matsumoto, Shunsuke Hashimoto, Takeshi Sugahara, Kazunari Ohgaki
Journal of Chemical & Engineering Data, 58(5), 1378-1381 (2013). [DOI]

A-71) Structure-H Methane+1,1,2,2,3,3,4-Heptafluorocyclopentane Mixed Hydrate at Pressures up to 373 MPa
Sumihiro Suzuki, Yuuki Matsumoto, Yoshito Katsuta, Shunsuke Hashimoto, Takeshi Sugahara, Kazunari Ohgaki
The Journal of Physical Chemistry A, 117(20), 4338-4341 (2013). [DOI]

A-72) In situ Raman Spectra of Hydrogen in Large Cages of Hydrogen+Tetrahydrofuran Mixed Hydrates
Akio Nishikawa, Tomohiro Tanabe, Kazuma Kitamura, Kazunari Ohgaki, Takeshi Sugahara
Chemical Engineering Science, 101, 1-4 (2013). [DOI]

A-73) Enclathration of 2,3,3,3-Tetrafluoropropene into Structure-II Hydrate with Methane
Yoshito Katsuta, Shunsuke Hashimoto, Teruo Kido, Takeshi Sugahara, Kazunari Ohgaki
Journal of Chemical & Engineering Data, 58(9), 2596-2599 (2013). [DOI]

-2014-
A-74) Phase Equilibrium Relations for Binary Mixed Hydrate Systems Composed of Carbon Dioxide and Cyclopentane Derivatives
Yuuki Matsumoto, Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
Fluid Phase Equilibria, 362, 379-382 (2014) [DOI]

A-75) Reactions of HOCO Radicals through Hydrogen-Atom Hopping Utilizing Clathrate Hydrates as an Observational Matrix
Motoi Oshima, Atsushi Tani, Takeshi Sugahara, Katsuhisa Kitano, Kazunari Ohgaki
Physical Chemistry Chemical Physics, 16, 3792-3797 (2014). [DOI]

A-76) Investigating the Thermodynamic Stabilities of Hydrogen and Methane Binary Gas Hydrates
Yuuki Matsumoto, R. Gary Grim, Naveed Muhammad Khan, Takeshi Sugahara, Kazunari Ohgaki, E. Dendy Sloan, Carolyn A. Koh, Amadeu K. Sum
The Journal of Physical Chemistry C, 118(7), 3783-3788 (2014). [DOI]

A-77) Thermodynamic Stability Boundaries and Structures of Methane+Monohalogenated Cyclopentane Mixed Hydrates
Yuuki Matsumoto, Hiroaki Matsukawa, Fumitaka Kamo, Young Bae Jeon, Yoshito Katsuta, Tatsuya Bando, Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
Journal of Chemical & Engineering Data, 59(7), 2294-2297 (2014). [DOI]

A-78) Nucleophilic Reactions of Bromocyclopentane in the Structure-H Methane+Bromocyclopentane Mixed Hydrate System at High Pressures
Yuuki Matsumoto, Yoshito Katsuta, Fumitaka Kamo, Tatsuya Bando, Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
The Journal of Physical Chemistry B, 118(47), 13404-13408 (2014). [DOI]
Special Issue: Physics and Chemistry of Ice 2014

A-79) Synergistic Formation of Carboxyl and Methyl Radicals in CO2+Methane Mixed Gas Hydrates
Motoi Oshima, Kazuma Kitamura, Atsushi Tani, Takeshi Sugahara, Kazunari Ohgaki
The Journal of Physical Chemistry B, 118(47), 13435-13439 (2014). [DOI]
Special Issue: Physics and Chemistry of Ice 2014

A-80) Blue-Colored tert-Butylamine Clathrate Hydrate
Atsushi Tani, Satoshi Koyama, Yusuke Urabe, Kenji Takato, Takeshi Sugahara, Kazunari Ohgaki
The Journal of Physical Chemistry B, 118(47), 13409-13413 (2014). [DOI]
Special Issue: Physics and Chemistry of Ice 2014

-2015-
A-81) High-Pressure Phase Equilibria of Tertiary-Butylamine Hydrates with and without Hydrogen
Tomohiro Tanabe, Takeshi Sugahara, Kazuma Kitamura, Takahiro Yamazaki, Takashi Fujimoto, Kazunari Ohgaki
Journal of Chemical & Engineering Data, 60(2), 222-227 (2015). [DOI]
Special Issue: In Honor of E. Dendy Sloan on the Occasion of His 70th Birthday

A-82) In Situ Raman Spectroscopic Studies on Small-Cage Occupancy of Methane in the Simple Methane and Methane + Deuterated Tetrahydrofuran Mixed Hydrates
Caroline Tiemi Moryama, Takeshi Sugahara, Danilo Yoshio Yatabe Franco, Hiroko Mimachi
Journal of Chemical & Engineering Data, 60(12), 3581-3587 (2015). [DOI]
Memorial Issue in Honor of Anthony R. H. Goodwin

-2016-
A-83) Phase Behavior of Ethane Hydrate System in the Presence of Ammonium Bromide
Tatsuya Bando, Takeshi Sugahara
Fluid Phase Equilibria, 413, 36-40 (2016). [DOI]
Special Issue : Gas Hydrates and Semicclathrate Hydrates

A-84) Four-Phase Equilibrium Relations Including Clathrate Hydrate Phase in a Ternary System of Xenon, Benzene, and Water
Takeshi Sugahara
Journal of Chemical & Engineering Data, 61(12), 4057-4060(2016). [DOI]

-2017-
A-85) Scanning Electron Microscopic Studies on the Methane Hydrate Decomposition Using the Freeze-Fracture Replica Method
Ayumi Fujimoto, Takeshi Sugahara
Bulletin of Glaciological Research, 35, 39-45 (2017). [DOI]
-2019-
A-86) Phase Equilibrium Relations for Tetra-n-butylphosphonium Acetate Semiclathrate Hydrate Systems in the Presence of Methane, Carbon Dioxide, Nitrogen, or Ethane
Masami Shimada, Jin Shimada, Takeshi Sugahara, Katsuhiko Tsunashima
Fluid Phase Equilibria, 488, 48-53 (2019). [DOI]

Article (peer-reviewed) - Crystallization of Phase Change Materials and Thermal Storage-

-2017-
B-1) Dissociation and Nucleation of Tetra-n-Butyl Ammonium Bromide Semi-Clathrate Hydrates at High Pressures
Takeshi Sugahara, Hironobu Machida
Journal of Chemical & Engineering Data, 62(9), 2721-2725 (2017). [DOI]
Memorial Issue in Honor of Ken Marsh.

B-2) Relationship between Supercooling Stability and Solution Structure in Sodium Acetate Aqueous Solution
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
Journal of Crystal Growth, 475, 295-299 (2017). [DOI]

-2018-
B-3) Memory Effect in Tetra-n-butyl Ammonium Bromide Semiclathrate Hydrate Reformation: the Existence of Solution Structures after Hydrate Decomposition
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
CrystEngComm, 20, 3328-3334 (2018). [DOI]

B-4) Phase Equilibrium Relations of Semiclathrate Hydrates Based on Tetra-n-butylphosphonium Formate, Acetate, and Lactate
Jin Shimada, Masami Shimada, Takeshi Sugahara, Katsuhiko Tsunashima, Atsushi Tani, Yusuke Tsuchida, Masahiko Matsumiya
Journal of Chemical & Engineering Data, 63(9), 3615-3620 (2018). [DOI]

-2019-
B-5) Phase Equilibrium Relations of Tetra-n-butylphosphonium Propionate and Butyrate Semiclathrate Hydrates
Jin Shimada, Masami Shimada, Takeshi Sugahara, Katsuhiko Tsunashima
Fluid Phase Equilibria, 485, 61-66 (2019). [DOI]

B-6) Preparation of Dispersed Metal Nanoparticles in the Aqueous Solution of Metal Carboxylate and the Tetra-n-butylammonium Carboxylate
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
Journal of Crystal Growth, 514, 14-20 (2019). [DOI]

B-7) Colossal Barocaloric Effects in Plastic Crystals
Bing Li, Yukinobu Kawakita, Seiko Ohira-Kawamura, Takeshi Sugahara, Hui Wang, Jingfan Wang, Yanna Chen, Saori I. Kawaguchi, Shogo Kawaguchi, Koji Ohara, Kuo Li, Dehong Yu, Richard Mole, Takanori Hattori, Tatsuya Kikuchi, Shin-ichiro Yano, Zhao Zhang, Zhe Zhang, Weijun Ren, Shangchao Lin, Osami Sakata, Kenji Nakajima, Zhidong Zhang
Nature, 567(7749), 506-510 (2019). [DOI]

B-8) Thermodynamic Properties of Tetra-n-butylammonium 2-Ethylbutyrate Semiclathrate Hydrate for Latent Heat Storage
Takeshi Sugahara, Hironobu Machida, Sanehiro Muromachi, Norio Tenma
International Journal of Refrigeration, 106, 113-119 (2019). [DOI]

-2020-
B-9) Calorimetric and Small-Angle X-ray Scattering Studies on the Memory Effect in the Tetra-n-butylammonium Bromide Semiclathrate Hydrate System
Hironobu Machida, Takeshi Sugahara, Hiroyasu Masunaga, Izumi Hirasawa
Journal of Crystal Growth, 533, 125476-1-6 (2020). [DOI]

-2021-
B-10) Phase Equilibrium Temperature and Dissociation Enthalpy in the tri-n-Butylalkylphosphonium Bromide Semiclathrate Hydrate Systems
Jin Shimada, Masami Shimada, Takeshi Sugahara, Katsuhiko Tsunashima, Yuta Takaoka, Atsushi Tani
Chemical Engineering Science, 236, 116514-1-8 (2021). [DOI]

B-11) The moment of initial crystallization captured on functionalized nanoparticles
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
Communications Materials, 2, 66-1-7 (2021). [DOI]

-2022-
B-12) Thermodynamic Properties of Tetra-n-butylphosphonium Dicarboxylate Semiclathrate Hydrates
Jin Shimada, Moe Yamada, Atsushi Tani, Takeshi Sugahara, Katsuhiko Tsunashima, Yusuke Tsuchida, Takayuki Hirai
Journal of Chemical & Engineering Data, 67(1), 67-73 (2022). [DOI]

B-13) Equilibrium Phase Relations and Dissociation Enthalpies of Tri-n-butylalkenylphosphonium Bromide Semiclathrate Hydrates
Sakura Azuma, Jin Shimada, Katsuhiko Tsunashima, Takeshi Sugahara, Atsushi Tani, Takayuki Hirai
Journal of Chemical & Engineering Data, 67(6), 1415-1420 (2022). [DOI]

B-14) Supercooling Suppression in the Tetrahydrofuran Clathrate Hydrate Formation
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
CrystEngComm, 24, 6730-6738 (2022). [DOI]

-2023-
B-15) Effect of Introducing a Cyclobutylmethyl Group to an Onium Cation on the Thermodynamic Properties of Ionic Clathrate Hydrate
Sakura Azuma, Jin Shimada, Katsuhiko Tsunashima, Takeshi Sugahara, Takayuki Hirai
New Journal of Chemistry, 47(1), 231-237 (2023). [DOI]

B-16) Peritectic Phase Behavior of Tetra-n-butylphosphonium Trifluoroacetate Semiclathrate Hydrate
Jin Shimada, Masami Shimada, Sakura Azuma, Takeshi Sugahara, Katsuhiko Tsunashima, Takayuki Hirai
Fluid Phase Equilibria, 567, 113727-1-5 (2023). [DOI]

B-17) Proton Conduction in Tetra-n-butylammonium Bromide Semiclathrate Hydrate
Jin Shimada, Yuta Takaoka, Takahiro Ueda, Atsushi Tani, Takeshi Sugahara, Katsuhiko Tsunashima, Hirohisa Yamada, Takayuki Hirai
Solid State Ionics, 393, 116188-1-8 (2023). [DOI]

B-18) Quasi-Elastic Neutron Scattering Studies on Fast Dynamics of Water Molecules in Tetra-n-butylammonium Bromide Semiclathrate Hydrate
Jin Shimada, Atsushi Tani, Takeshi Yamada, Takeshi Sugahara, Takayuki Hirai, Takuo Okuchi
Applied Physics Letters, 123(4), 044104-1-6 (2023). [DOI]

B-19) Thermodynamic Properties of Tetra-n-butylammonium and Tetra-n-butylphosphonium Hydroxycarboxylate Semiclathrate Hydrates
Kazuhiro Minamikawa, Jin Shimada, Takeshi Sugahara, Takayuki Hirai
Journal of Chemical & Engineering Data, 68, 3492-3987 (2023). [DOI]

B-20) Giant Adiabatic Temperature Change and Its Direct Measurement of a Barocaloric Effect in a Charge-Transfer Solid
Shin-ichi Ohkoshi, Kosuke Nakagawa, Marie Yoshikiyo, Asuka Namai, Kenta Imoto, Yugo Nagane, Fangda Jia, Olaf Stefanczyk, Hiroko Tokoro, Junhao Wang, Takeshi Sugahara, Kouji Chiba, Kazuhiko Motodohi, Kazuo Isogai, Koki Nishioka, Takashi Momiki, Ryu Hatano
Nature Communications, 14, 8466-1-12 (2023). [DOI]

-2024-
B-21) Effects of Halide Anions on the Electrical Conductivity in Single-Crystalline Tetra-n-butylammonium Salt Semiclathrate Hydrates
Jin Shimada, Takeshi Sugahara, Atsushi Tani, Takahiro Ueda, Riko Tsugaya, Katsuhiko Tsunashima, Takayuki Hirai
Energy & Fuels, 38, 6471-6477 (2024). [DOI]

  

Article (peer-reviewed) - Structures of Clathrate Compounds (not clathrate hydrates) -

C-1) Selective CO2 Trapping in Guest-Free Hydroquinone Clathrate Prepared by Gas-Phase Synthesis
Yun-Je Lee, Kyu Won Han, Jin Seok Jang, Tae-In Jeon, Jeasung Park, Taro Kawamura, Yoshitaka Yamamoto, Takeshi Sugahara, Thomas Vogt, Jong-Won Lee, Yongjae Lee, Ji-Ho Yoon
ChemPhysChem, 12, 1056-1059 (2011). [DOI]

C-2) Fast and Reversible Hydrogen Storage in Channel Cages of Hydroquinone Clathrate
Kyu Won Han, Yun-Je Lee, Jin Seok Jang, Tae-In Jeon, Jeasung Park, Taro Kawamura, Yoshitaka Yamamoto, Takeshi Sugahara, Thomas Vogt, Jong-Won Lee, Yongjae Lee, Ji-Ho Yoon
Chemical Physics Letters, 546, 120-124 (2012). [DOI]

C-3) Enclathration of Ethane, Propane, and Propylene into Urea Clathrates and Roles of Methanol on Urea Clathrate Formation
Takahiro Yamazaki, Tomohiro Tanabe, Takeshi Sugahara
ACS Omega, 3(10), 13154-13159 (2018). [DOI]

C-4) Separation of Propane and Propylene by Urea Clathrate Formation
Ryosuke Kobatake, Takeshi Sugahara, Takayuki Hirai
Industrial & Engineering Chemistry Research, 62, 21380-21384 (2023). [DOI]

  

Article (peer-reviewed) - Others -

D-1) Non-Equilibrium MD Studies on Gas Permeation through Carbon Membranes with Belt-like Heterogeneous Surfaces
Shin-ichi Furukawa, Takeshi Sugahara, Tomoshige Nitta
Journal of Chemical Engineering of Japan, 32(2), 223-228 (1999) [DOI]

D-2) Pressure-Induced Evolution in Durability of Nickel-Metal Hydride Battery under High-Current Charge
Kouji Maeda, Masato Moritoki, Shinji Yae, Keisuke Fukui, Naoki Fukumoto, Takeshi Sugahara
Physical Chemistry Chemical Physics, 24, 14085-14091 (2022) [DOI]

  

Review Articles in Japanese

X-1) Phase Behavior for Pure and MIxed Gas Hydrate Systems
Takeshi Sugahara, Keisuke Sugahara, Kazunari Ohgaki
The Review of High Pressure Science and Technology, 12(1), 34-39 (2002) [JOI]

X-2) Phase Behavior and Structural Phase Transition of Methane Hydrates
Kazunari Ohgaki, Takeshi Sugahara
Bulletin of the Society of Sea Water Science, Japan, 56(4), 292-296 (2002)

X-3) Interesting and Significant Behavior for the Mixed Gas Hydrates
Takeshi Sugahara, Takashi Makino
Seminor Series of The Japan Society of High Pressure Science and Technology , 26, 1-8 (2003)

X-4) Affairs and Problems for the Applicable Research Using Gas Hydrates
Takeshi Sugahara
Seminor Series of the Heat Transfer Society of Japan, Chugoku-Shikoku Branch, 16, 38-47 (2004)

X-5) Thermodynamic Stability of Gas Hydrates and Cage Occupancy of Guest Species
Takeshi Sugahara
The Review of High Pressure Science and Technology, 16(2), 155-166 (2006)(Review in remembrance of Prize for encouragement) [JOI]

X-6) Capability of Gas Hydrates as Hydrogen Storage Medium
Kazunari Ohgaki, Takeshi Sugahara
Journal of The Hydrogen Energy Systems Society of Japan, 32(4), 20-26 (2007)

X-7) Storage Capacity of Hydrogen on Gas Hydrates: - Current State and Assignment -
Shunsuke Hashimoto, Takeshi Sugahara, Hiroshi Sato, Kazunari Ohgaki
Catalysts and Catalysis, 51(4), 298-303 (2009).

X-8) Science and Engineering on Gas Hydrates
Takeshi Sugahara, Kazunari Ohgaki
Chemical Education, 60(1), 8-13 (2012).

X-9) Molecular Hydrogen Storage at Milder Temperatures and Pressures
Takeshi Sugahara
Departmental Bulletin Paper of Low-Temperature Center in Osaka Univ., 157, 1-5 (2012). [link]

X-10) Characteristics of Gas Hydrates through Observation of Radical Species
Atsushi Tani, Takeshi Sugahara, Motoi Oshima, Kei Takeya, Kazunari Ohgaki
Low Temperature Science, 71, 187-192 (2013). [Link]

X-11) Prospects for the Development of Phase Equilibrium Estimation of Clathrate Hydrates Based on van der Waals & Platteeuw Model - Report from the Symposium at the 53rd High Pressure Conference of Japan -
Tsutomu Uchida, Takeshi Sugahara, Kazunari Ohgaki, Hideki Tanaka, Satoshi Takeya, Atsushi Tani
The Review of High Pressure Science and Technology, 23(2), 141-147 (2013). [DOI]

X-12) Gas Separation Using Gas Hydrates
Takeshi Sugahara
Bunri Gijyutu, 47(3), 29-34 (2017).

X-13) Cage Occupancy of Guest Molecules and Thermodynamic Stability of Gas Hydrates (written in Japanese)
Takeshi Sugahara
Refrigeration, 93, 13-17 (2018).

X-14) Equilibrium Phase Relations of Gas Hydrates and Cage Occupancy of Guest Species (written in Japanese)
Takeshi Sugahara
Journal of the Japan Institute of Energy "Enermix", 98(1), 47-51 (2019).

X-15) Hysteresis of Crystallization Derived from Residual Solution Structures after Semiclathrate Hydrate Decomposition (written in Japanese)
Takeshi Sugahara, Hironobu Machida
Japanese J. Multiphase Flow, 35(4), 516-524 (2021).

X-16) Structural Evaluation of Tetra-n-butylammonium Bromide Supercooled Aqueous Solution (written in Japanese)
Hiroyasu Masunaga, Hironobu Machida, Tetsuo Katayama, Yoshinori Nishino, Akihiro Suzuki,Takeshi Sugahara
Spring-8/SACLA Research Report, 11(5), 382-386 (2021).

X-17) Dynamics of Water Molecules around Ions in the Crystalline Solids (written in Japanese)
Jin Shimada, Takeshi Sugahara, Takayuki Hirai
Chemistry, 79(1), 33-36 (2024).

X-18) Phase Behavior of Clathrate Hydrates Including Carbon Dioxide (written in Japanese)
Takeshi Sugahara
Journal of the Japan Institute of Energy "Enermix"103(2), 152-158 (2024).

X-19) Potential of Clathrate Hydrate as a Cold Storage Material (written in Japanese)
Hironobu Machida, Takeshi Sugahara
Journal of the Japan Institute of Energy "Enermix"103(2), 173-178 (2024).

  

International Conferences

Y-1) NEMD Studies of Surface Heterogeneity Effects on Gas Permeation through Carbon Membranes
Takeshi Sugahara, Shin-ichi Furukawa, Tomoshige Nitta
Fifth International Conference on Inorganic Membranes, P-131, Nagoya, Japan (1998.7)

Y-2) Small Cage-Occupancy of Guest Species in the Ethane, Ethylene and Cyclopropane Hydrate Systems
Takeshi Sugahara, Keisuke Sugahara, Kazunari Ohgaki
Proceedings of the Fourth International Conference on Gas Hydrates, Vol. 2, pp.608-613(2002.5), Yokohama, Japan

Y-3) Cage-Occupancy of Guest Species for Mixed Gas Hydrates
Takeshi Sugahara
The 1st International 21 Century COE Symposium on Integrated EcoChemistry, pp.29, Suita, Japan (2003. 2)

Y-4) Feasibility Studies on Gas Separation Using Gas Hydrates - CO2 + H2 Mixed System -
Takeshi Sugahara
The 2nd International 21 Century COE Symposium on Integrated EcoChemistry, Awaji Island, Japan (2003.7.18-19)

Y-5) Fundamental Studies on H2 Separation Process from H2 + CO2 Mixed Gas Using Gas Hydrates
Takeshi Sugahara, Shu Murayama
The 3rd International 21 Century COE Symposium on Integrated EcoChemistry, Suita, Japan (2004.1.23-24)

Y-6) Hydrate Structural Transition Depending on the Composition of Methane + Cyclopropane Mixed Hydrate
Takashi Makino, Makoto Tongu, Takeshi Sugahara, Kazunari Ohgaki
The 3rd International 21 Century COE Symposium on Integrated EcoChemistry, Suita, Japan (2004.1.23-24)

Y-7) Crystal Structures and Gas Content of NGH
Takeshi Sugahara,Takashi Makino, Kazunari Ohgaki
International Forum of Natural Gas Hydrate Carrier, Tokyo, Japan (2004.3.26)

Y-8) Behavior of γ-ray Induced Methyl Radical in Methane Hydrate
Kei Takeya, Atsushi Tani, Takeshi Sugahara, Kazunari Ohgaki
The 4th International 21 Century COE Symposium on Integrated EcoChemistry, Osaka, Japan (2004.8.30-31)

Y-9) Phase Equilibria for the Tetrahydrofuran+Water Hydrate System below the Atmospheric Pressure Condition
Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
The 4th International 21 Century COE Symposium on Integrated EcoChemistry,Osaka, Japan (2004.8.30-31)

Y-10) Thermodynamic Stability of Structure-H Hydrates of Dimethylcyclohexane Stereo-Isomers Helped by Methane
Takashi Makino, Tsutomu Hara, Takeshi Sugahara, Kazunari Ohgaki
The 5th International 21 Century COE Symposium on Integrated EcoChemistry,Osaka, Japan (2005.1.27-28)

Y-11) Gamma-Ray Irradiation Effects of Ethane and Ethylene Hydrates
Kei Takeya, Kouhei Nango, Atsushi Tani, Takeshi Sugahara, Kazunari Ohgaki
The 5th International 21 Century COE Symposium on Integrated EcoChemistry,Osaka, Japan (2005.1.27-28)

Y-12) Isothermal Phase Equilibria for the Mixed Gas Hydrate Systems
Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
5th International Conference on Gas Hydrates, Trondheim (2005.6.13-16)

Y-13) Radicals induced by gamma-ray irradiation in gas hydrates
Kei Takeya, Kouhei Nango, Atsushi Tani, Takeshi Sugahara, Kazunari Ohgaki
5th International Conference on Gas Hydrates, Trondheim(2005.6.13-16)

Y-14) Thermodynamic Stability and Content of Guest Species for Structure-H Hydrate System
Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
The 7th International 21 Century COE Symposium on Integrated EcoChemistry, Honolulu, USA(2005.12.18-23)

Y-15) Phase Equilibria for H2+CO2+Tetrahydrofuran+Water Mixed System Containing Gas Hydrates
Shunsuke Hashimoto, Shu Murayama, Takeshi Sugahara, Kazunari Ohgaki
The 7th International 21 Century COE Symposium on Integrated EcoChemistry, Honolulu, USA(2005.12.18-23)

Y-16) Fundamental Studies for A New H2 Separation Method Using Gas Hydrates
Shunsuke Hashimoto, Shu Murayama, Takeshi Sugahara, Kazunari Ohgaki
Physics and Chemistry of Ice (PCI 2006), Bremerhaven, Germany(2006.7.23-28)

Y-17) Effects of Large Guest Species on Thermodynamic Properties of Structure-H Hydrates
Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
Physics and Chemistry of Ice (PCI 2006), Bremerhaven, Germany(2006.7.23-28)

Y-18) Investigation of Methane Hydrate Dissociation through Decay of Radiation-Induced Methyl Radical in Methane Hydrate
Kei Takeya, Kouhei Nango, Takeshi Sugahara, Atsushi Tani, Kazunari Ohgaki
Physics and Chemistry of Ice (PCI 2006), Bremerhaven, Germany(2006.7.23-28)

Y-19) Structure of Mixed Gas Hydrates and Cage Occupancy of CH4
Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
The 8th International 21 Century COE Symposium on Integrated EcoChemistry, Keihanna, Kyoto, Japan(2006.8.28-29)

Y-20) Thermodynamic and Raman Spectroscopic Studies on Mixed Gas Hydrates Containing Hydrogen
Shunsuke Hashimoto, Shu MUrayama, Takeshi Sugahara, Kazunari Ohgaki
The 8th International 21 Century COE Symposium on Integrated EcoChemistry, Keihanna, Kyoto, Japan(2006.8.28-29)

Y-21) Thermodynamic Stability of H2 + Tetrahydrofuran Mixed Gas Hydrate in Non-Stoichiometric Aqueous Solutions
Shunsuke Hashimoto, Takeshi Sugahara, Masato Moritoki, Hiroshi Sato, Kazunari Ohgaki
The 9th International 21 Century COE Symposium on Integrated EcoChemistry, Awaji, Japan(2007.1.16-18)

Y-22) Thermodynamic Stability of Mixed Gas Hydrates Containing Hydrogen
Shunsuke Hashimoto, Takeshi Sugahara, Masato Moritoki, Hiroshi Sato, Kazunari Ohgaki
The Joint 21st AIRAPT & 45th EHPRG International Conference on "High Pressure Science and Technology", Catania, Italy(2007.9.17-21)

Y-23) Search of Effective Additives for Hydrogen Storage Using Gas Hydrates
Shunsuke Hashimoto, Jun Sakamoto, Kyohei Ogata, Takeshi Sugahara, Kazunari Ohgaki
The 1st International Global COE Symposium on Bio-Environmental Chemistry, Osaka, Japan(2008.1.27-29)

Y-24) Cage Occupancies of Hydrogen Molecule and Thermodynamic Stabilities of Hydrogen-Containing Hydrates
Takeshi Sugahara, Shunsuke Hashimoto, Hiroki Mori, Jun Sakamoto, Kyohei Ogata, Kazunari Ohgaki
6th International Conference on Gas Hydrates, Vancouver, Canada(2008.7.6-10)

Y-25) Phase Equilibrium Relations of Methylcyclohexanol Stereoisomer Hydrates Helped by Methane - Effect of Substitution Site -
Takashi Makino, Michiko Mori, Takeshi Sugahara, Kazunari Ohgaki
6th International Conference on Gas Hydrates, Vancouver, Canada(2008.7.6-10)

Y-26) ESR spectral analysis of free radicals in irradiated gas hydrates below 77 K
Atsushi Tani, Kei Takeya, Takeshi Sugahara, Kazunari Ohgaki
6th International Conference on Gas Hydrates, Vancouver, Canada(2008.7.6-10)

Y-27) Storage Capacity of Hydrogen in Gas Hydrates
Takaaki Tsuda, Kyohei Ogata, Shunsuke Hashimoto, Takeshi Sugahara, Hiroshi Sato, Kazunari Ohgaki
Joint AIRAPT-22 & HPCJ-50 International Conference on "High Pressure Science and Technology", Tokyo, Japan(2009.7.26-31)

Y-28) Hydrogen Storage in Clathrate Hydrates
Joanna C. Haag, Takeshi Sugahara, Pinnelli S. R. Prasad, Ashleigh A. Warntjes, E. Dendy Sloan, Amadeu K. Sum, Carolyn A. Koh
Fall 2009 Meeting of the Four Corners Section of the APS, Colorado, USA(2009.10.23-24)

Y-29) Hydrogen Storage in Clathrate Hydrates: the Tuning Effect
Takeshi Sugahara, Joanna C. Haag, Pinnelli S. R. Prasad, Ashleigh A. Warntjes, E. Dendy Sloan, Amadeu K. Sum, Carolyn A. Koh
5th Eastern Clathrate Conference - Hydrate Day 2009, Kingston, Canada(2009.10.30)

Y-30) Application Possibilities of Clathrate Hydrates - Current & Challenge(invited keynote speech)
Takeshi Sugahara
The 6th International Chemical Engineering Congress & Exhibition, Kish island, Iran(2009.11.16-20)

Y-31) Experimental Approaches to Natural-gas Recovery from Natural-Gas Hydrate Field(invited speech)
Takeshi Sugahara
Symposium on Methane Hydrate Recovery & CO2 Sequestration, Taipei, Taiwan(2010.3.3)

Y-32) Molecular Storage of H2 in Clathrate Hydrates
Takeshi Sugahara, P.S.R. Prasad, Carolyn A. Koh, E. Dendy Sloan, Amadeu K. Sum
The 12th International Conference on Properties and Phase Equilibria for Product and Process Design (PPEPPD 2010), Suzhou, China(2010.5.19)

Y-33) Hydrogen Storage in tri‐Methylamine Clathrates
Pinnelli S. R. Prasad, Takeshi Sugahara, E. Dendy Sloan, Amadeu K. Sum, Carolyn A. Koh
XXII INTERNATIONAL CONFERENCE ON RAMAN SPECTROSCOPY, Boston, UK(2010.8.8-10)

Y-34) Large-Cage Occupancy of Molecular Hydrogen in Binary Clathrate Hydrates Dependent on Pressures(invited speech)
Takeshi Sugahara, P.S.R. Prasad, E. Dendy Sloan, Amadeu K. Sum, Carolyn A. Koh, Kazunari Ohgaki
12th International Conference on Physics and Chemistry of Ice (PCI2010), Sapporo, Japan(2010.9.9)

Y-35) Raman Spectroscopic Analysis of Mixed Gas Hydrate Crystals
Hiroko Mimachi, Masahiro Takahashi, Toru Iwasaki, Takahiro Kinoshita, Takeshi Sugahara, Hiroshi Sato, Kazunari Ohgaki
12th International Conference on Physics and Chemistry of Ice (PCI2010), Sapporo, Japan(2010.9.7)

Y-36) In-situ Raman Observation on Aqueous solution around Tetra-n-Butyl Ammonium Bromide Semi-Clathrate Hydrate
Motoi Oshima, Shunsuke Hashimoto, Wataru Shimada, Atsushi Tani, Takeshi Sugahara, Kazunari Ohgaki
12th International Conference on Physics and Chemistry of Ice (PCI2010), Sapporo, Japan(2010.9.9)

Y-37) Decay Mechanisms of Radiation-Induced Radicals in Sulfur Hexafluoride Clathrate Hydrate
Kenji Takato, Atsushi Tani, Takeshi Sugahara, Kei Takeya, Kazunari Ohgaki
12th International Conference on Physics and Chemistry of Ice (PCI2010), Sapporo, Japan(2010.9.9)

Y-38) Thermal Stability of Radicals Induced Xenon Hydrate
Kei Takeya, Atsushi Tani, Takeshi Sugahara, and Kazunari Ohgaki
12th International Conference on Physics and Chemistry of Ice (PCI2010), Sapporo, Japan(2010.9.9)

Y-39) In-situ ESR Observation of Free Radicals in Gas Hydrates under High Pressure
Atsushi Tani, Kenji Takato, Takeshi Sugahara, Kazunari Ohgaki, Kei Takeya
12th International Conference on Physics and Chemistry of Ice (PCI2010), Sapporo, Japan(2010.9.9)

Y-40) Effect of Cyclopentane on Cage Occupancy of Hydrogen in Clathrate Hydrates
Takaaki Tsuda, Shunsuke Hashimoto, Takeshi Sugahara, Kazunari Ohgaki
12th International Conference on Physics and Chemistry of Ice (PCI2010), Sapporo, Japan(2010.9.9)

Y-41) Thermal Stabilities of Radiation-Induced Radicals in CO2 Hydrate
Motoi Oshima, Atsushi Tani, Katsuhisa Kitano, Takeshi Sugahara, Kazunari Ohgaki
13th International Conference on Luminescence and Electron Spin Resonance Dating, Toruń, Poland(2011.7.10-14)

Y-42) Molecular Storage of Hydrogen in Simple and Binary Clathrate Hydrates
Takeshi Sugahara, P.S.R. Prasad, Vahid Taghikhani, Takaaki Tsuda, Kazunari Ohgaki, E. Dendy Sloan, Amadeu K. Sum, Carolyn A. Koh
7th International Conference on Gas Hydrates (ICGH7), Edinburgh, UK(2011.7.20-21)

Y-43) Structural Phase Transitions of Methane+Ethane Mixed-gas Hydrate Induced by 1,1-Dimethylcyclohexane
Yuuki Matsumoto, Hiroshi Miyauchi, Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
7th International Conference on Gas Hydrates (ICGH7), Edinburgh, UK(2011.7.19)

Y-44) Enhancement of Hydrogen Storage Rate in Pre-treated Semi-clathrate Hydrates
Takaaki Tsuda, Shingo Amano, Yuuya Fujisawa, Shunsuke Hashimoto, Takeshi Sugahara, Kazunari Ohgaki
7th International Conference on Gas Hydrates (ICGH7), Edinburgh, UK(2011.7.20-21)

Y-45) Effect of Ionic Liquid on Hydrate Formation Rate in Carbon Dioxide Hydrates
Takashi Makino, Yuuki Matsumoto, Hiroki Masuda, Takeshi Sugahara, Kazunari Ohgaki
7th International Conference on Gas Hydrates (ICGH7), Edinburgh, UK(2011.7.18-19)

Y-46) Identification of Products Induced by gamma-ray Irradiation in CO2 Hydrate
Motoi Oshima, Shinsuke Kitani, Atsushi Tani, Katsuhisa Kitano, Takeshi Sugahara, Kazunari Ohgaki
7th International Conference on Gas Hydrates (ICGH7), Edinburgh, UK(2011.7.21)

Y-47) Structural Stability of (t-BuNH2-H2/CH4) Binary Hydrates
Pinnelli S.R. Prasad, Takeshi Sugahara, E. Dendy Sloan, Amadeu K. Sum, Carolyn A. Koh
7th International Conference on Gas Hydrates (ICGH7), Edinburgh, UK(2011.7.18-19)

Y-48) Possibility of Carboxylic Acid Formation by Radiolysis of CO2 Hydrate on Mars
Motoi Oshima, Shinsuke Kitani, Atsushi Tani, Katsuhisa Kitano,Takeshi Sugahara, Kazunari Ohgaki
43rd Lunar and Planetary Science Conference, The Woodlands (Texas), US(2012.3.19-23)

Y-49) Phase Behavior for Carbon Dioxide + Cyclopentane Derivative Mixed Hydrate Systems
Yuki Matsumoto, Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
13th International Conference on Properties and Phase Equilibria for Products and Process Design (PPEPPD2013), Iguazu falls, Brazil-Argentina (2013.5.26-30)

Y-50) Increasing the Energy Storage Capacity of Clathrate Hydrates with Hydrogen and Methane
Yuki Matsumoto, R. Gary Grim, Takeshi Sugahara, Kazunari Ohgaki, E. Dendy Sloan, Carolyn A. Koh, Amadeu K. Sum
13th International Conference on Properties and Phase Equilibria for Products and Process Design (PPEPPD2013), Iguazu falls, Brazil-Argentina (2013.5.26-30)

Y-51) Experimental Observation of Competitive Occupancy into the Cages of Structure-II Hydrates During H2 Enclathration
Takeshi Sugahara, Yuuya Fujisawa, Akio Nishikawa, Kazuma Kitamura, Takahiro Yamazaki, Yuuki Matsumoto, Kazunari Ohgaki
13th International Conference on the Physics and Chemistry of Ice (PCI-2014), Hanover, NH, USA (2014.3.17-20)

Y-52) High-Pressure Phase Equilibria of Structure-H Hydrate Sysems Enclathrating Methane and Large Guest Species
Yuuki Matsumoto, Yoshito Katsuta, Tatsuya Bando, Fumitaka Kamo, Sumihiro Suzuki, Takashi Makino, Takeshi Sugahara, Kazunari Ohgaki
13th International Conference on the Physics and Chemistry of Ice (PCI-2014), Hanover, NH, USA (2014.3.17-20)

Y-53) Hydrogen-Atom Hopping between Guest Species in CO2 Hydrates
Motoi Oshima, Atsushi Tani, Takeshi Sugahara, Katsuhisa Kitano, and Kazunari Ohgaki
13th International Conference on the Physics and Chemistry of Ice (PCI-2014), Hanover, NH, USA (2014.3.17-20)

Y-54) Blue-Colored Clathrate Hydrate
Atsushi Tani, Yusuke Urabe, Kenji Takato, Satoshi Koyama, Takeshi Sugahara, Kazunari Ohgaki
13th International Conference on the Physics and Chemistry of Ice (PCI-2014), Hanover, NH, USA (2014.3.17-20)

Y-55) Formation and Stabilization of Radicals in Methane and CO2 Mixed Hydrates
Motoi Oshima, Kazuma Kitamura, Atsushi Tani, Takeshi Sugahara, Kazunari Ohgaki
13th International Conference on the Physics and Chemistry of Ice (PCI-2014), Hanover, NH, USA (2014.3.17-20)

Y-56) Trapped Electron in Electron Pulse Irradiated Clathrate Hydrates
Satoshi Koyama, Atsushi Tani, Kimihiro Norizawa, Takafumi Kondo, Takeshi Sugahara, Kazunari Ohgaki, Koichi Kan, Jinfeng Yang, Yoichi Yoshida
13th International Conference on the Physics and Chemistry of Ice (PCI-2014), Hanover, NH, USA (2014.3.17-20)

Y-57) Thermodynamic Stabilities of Simple and Mixed Hydrates Containing Tertiary-Butyl Amine
Takeshi Sugahara, Tomohiro Tanabe, Kazuma Kitamura, Takahiro Yamazaki, Kazunari Ohgaki
8th International Conference on Gas Hydrates (ICGH8), Beijing, China (2014.7.28-8.1)

Y-58) Investigating the Thermodynamic Properties of Gas Hydrates Including Hydrogen and Methane
Yuki Matsumoto, R. Gary Grim, Naveed M. Khan, Takeshi Sugahara, Kazunari Ohgaki, E. Dendy Sloan, Carolyn A. Koh, Amadeu K. Sum
8th International Conference on Gas Hydrates (ICGH8), Beijing, China (2014.7.28-8.1)

Y-59) Cage occupancy of hydrogen molecules in the structure I, II, H, and VI hydrates
Takeshi Sugahara, Yuuya Fujisawa, Takashi. Fujimoto, Kazuma Kitamura
19th Symposium on Thermophysical Properties, Boulder, US (2015.6.21-6.26)

Y-60) Mechanism of Synergistic Methyl Radical Formation in CH4+CO2 Mixed Gas Hydrates Systems
Danilo Yoshio Yatabe Franco, Kazuma Kitamura, Motoi Oshima, Takeshi Sugahara, Atsushi Tani
19th Symposium on Thermophysical Properties, Boulder, US (2015.6.21-6.26)

Y-61) Thermodynamic Stability of Xenon+Benzene Mixed Hydrates
Takeshi Sugahara
14th International Conference on Properties and Phase Equilibria for Product and Process Design, Porto, Portugal (2016.5.22-5.26)

Y-62) Observation of Crystal Structure of TBAB Semiclathrate Hydrate by SEM
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
9th International Conference on Gas Hydrates (ICGH9), Denver, US (2017.6.25-6.30)

Y-63) Structure Observation of Sodium Acetate Supercooled Aqueous Solution
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
The 5th international symposium & Exhibition on “Aqua Science and Water Resources (ISASWR’17)”, Fukuoka, Japan (2017.8.8-11)
Excellent Poster Presentation Award (Researcher)!

Y-64) SEM Observation on Hydrate Formation from TBAB Aqueous Solution and Memory Effect
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
14th International Conference on the Physics and Chemistry of Ice (PCI-2018), ETH Zürich, Switzerland (2018.1.8-12)

Y-65) SEM Observation of Semiclathrate Hydrate and Supercooled Aqueous Solution
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
4th Asian Crystallization Technology Symposium (ACTS-2018), Biopolis, Singapore (2018.6.20-6.22)

Y-66) Supercooling Suppression and Memory Effect in Semiclathrate Hydrate Crystallization
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
4th Asian Crystallization Technology Symposium (ACTS-2018), Biopolis, Singapore (2018.6.20-6.22)

Y-67) Structure Observation of Sodium Acetate Supercooled Aqueous Solution
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
4th Asian Crystallization Technology Symposium (ACTS-2018), Biopolis, Singapore (2018.6.20-6.22)

Y-68) Phase Equilibrium Measurement of Semiclathrate Hydrates by Differential Scanning Calorimetry
Takeshi Sugahara, Hironobu Machida
8th International Symposium on Molecular Thermodynamics and Molecular Simulation (MTMS'18), Narashino, Japan (2018.9.4-9.7)

Y-69) Memory Effect and Hydrate Reformation from TBAB Aqueous Solution - SEM Observation
Hironobu Machida, Hiroyasu Masunaga, Takeshi Sugahara, Izumi Hirasawa
8th International Symposium on Molecular Thermodynamics and Molecular Simulation (MTMS'18), Narashino, Japan (2018.9.4-9.7)

Y-70) Phase Equilibrium Relations of Semiclathrate Hydrates Based on Tetra-n-butylphosphonium Formate, Acetate, Propionate and Lactate
Jin Shimada, Masami Shimada, Takeshi Sugahara, Katsuhiko Tsunashima
8th International Symposium on Molecular Thermodynamics and Molecular Simulation (MTMS'18), Narashino, Japan (2018.9.4-9.7)
Mr. Jin Shimada won Student Poster Presentation Award!

Y-71) Thermodynamic Stabilities of Tetra-n-butylphosphonium + Gas Semiclathrate Hydrate Systems
Masami Shimada, Takeshi Sugahara, Katsuhiko Tsunashima
8th International Symposium on Molecular Thermodynamics and Molecular Simulation (MTMS'18), Narashino, Japan (2018.9.4-9.7)

Y-72) Ionic Conductivities in Ionic Clathrate Hydrates Based on Quaternary Ammonium and Phosphonium Salts
Jin Shimada, Takeshi Sugahara, Hirohisa Yamada, Katsuhiko Tsunashima
6th Asian-Pacific Conference on Ionic Liquids & Green Processes (APCIL-6), Yonago, Japan (2018.10.31-11.3)

Y-73) Memory Effect and Hydrate Reformation from TBAB Aqueous Solution
Takeshi Sugahara, Hironobu Machida, Hiyoyasu Masunaga, Izumi Hirasawa
15th International Conference on Properties and Phase Equilibria for Product and Process Design (PPEPPD2019), Vancouver, Canada (2019.5.12-5.16)

Y-74) Observation of Solution Structures and Supercooling Suppression in Semiclathrate hydrate Recrystallization
Takeshi Sugahara, Hironobu Machida, Izumi Hirasawa
19th International Conference on Crystal Growth and Epitaxy (ICCGE-19), Keystone, CO, USA (2019.7.28-8.2)

Y-75) Observation of memory effect in TBAB supercooled aqueous solution
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
18th Asian Pacific Confederation of Chemical Engineering Congress (APCChE 2019), Sapporo, Japan (2019.9.23-9.27)

Y-76) Various Behavior Derived from Solution Structures in TBAB Aqueous Solution
Takeshi Sugahara, Hironobu Machida, Hiroyasu Masunaga, Izumi Hirasawa
JST-Mirai-Project International Workshop on Latent Heat Engineering, Mito, Japan (2019.12.2-12.3)

Y-77) Thermodynamic Stabilities of Clathrate Hydrates Including Tetrahydrofuran and Quaternary Onium Salts
Takeshi Sugahara, Hironobu Machida
The 9th International Symposium on “Molecular Thermodynamics and Molecular Simulation” (MTMS ’21), Online (2021.9.7-9)

Y-78) Thermodynamic Properties of Tetra-n-butylphosphonium Dicarboxylate Semiclathrate Hydrates
Jin Shimada, Moe Yamada, Takeshi Sugahara, Atsushi Tani, Katsuhiko Tsunashima, Takayuki Hirai
The 9th International Symposium on “Molecular Thermodynamics and Molecular Simulation” (MTMS ’21), online (2021.9.7-9)

Y-79) Phosphonium salts as Potential Guest Substances for Ionic Semiclathrate Hydrates
Sakura Azuma, Katsuhiko Tsunashima, Jin Shimada, Takeshi Sugahara, Atsushi Tani,
242nd Electrochemical Society Meeting, Atlanta, GA, US (2022.10.9-13)

Y-80) Design of Semiclathrate Hydrates for Thermal Storage
Takeshi Sugahara, Hironobu Machida, Jin Shimada, Kazuhiro Minamikawa, Takayuki Hirai
16th International Conference on Properties and Phase Equilibria for Products and Process Design (PPEPPD2023), Tarragona, Spain (2023.5.21-25)

Y-81) Clathrate Hydrates for Thermal Storage – Design of Ionic Guest Species and Supercooling Suppression –
Takeshi Sugahara, Hironobu Machida, Jin Shimada, Kazuhiro Minamikawa, Takayuki Hirai
10th International Conference on Gas Hydrates (ICGH10), Singapore (2023.7.9-14)

Y-82) Supercooling Suppression of Semiclathrate Hydrates by Promoting Cluster Formation
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
10th International Conference on Gas Hydrates (ICGH10), Singapore (2023.7.9-14)

Y-83) Proton Conduction in Tetra-n-butylammonium Bromide Semiclathrate Hydrate
Jin Shimada, Takeshi Sugahara, Atsushi Tani, Takahiro Ueda, Katsuhiko Tsunashima, Takayuki Hirai
10th International Conference on Gas Hydrates (ICGH10), Singapore (2023.7.9-14)

Y-84) Proton Conduction Mechanism in TBAB Semiclathrate Hydrate Obtained by NMR and QENS Measurements
Jin Shimada, Takeshi Sugahara, Atsushi Tani, Takahiro Ueda, Takeshi Yamada, Takuo Okuchi, Katsuhiko Tsunashima, Takayuki Hirai
15th International Conference on the Physics and Chemistry of Ice (PCI2023), Sapporo, Japan (2023.9.4-8)

Y-85) Effect of Functional Group in Dicarboxylate Anions on the Latent Heat Storage Properties of Semiclathrate Hydrates
Kazuhiro Minamikawa, Jin Shimada, Takeshi Sugahara, Katsuhiko Tsunashima, Takayuki Hirai
15th International Conference on the Physics and Chemistry of Ice (PCI2023), Sapporo, Japan (2023.9.4-8)

Y-86) Supercooling Suppression in the Tetrahydrofuran Clathrate Hydrate Formation
Hironobu Machida, Takeshi Sugahara, Izumi Hirasawa
15th International Conference on the Physics and Chemistry of Ice (PCI2023), Sapporo, Japan (2023.9.4-8)