Yukihiro Higashi | Last modified date：2022.09.11 |

Professor /
Reseach Center for Next Generation Refrigerant Properties /
International Institute for Carbon-Neutral Energy Research

**Presentations**

1. | Yukihiro Higashi, Masahiko Uematsu, Koichi Watanabe, CRITICAL LOCUS FOR SEVERAL BINARY MIXTURES OF HALOGENATED HYDROCARBONS., 1984.12, Measurements of the vapor-liquid coexistence curve in the critical region have been continued by visual observation of the disappearance of the meniscus at the vapor-liquid interface within an optical cell. The experimental results for dichlorodifluoromethane plus chlorodifluoromethane and chlorodifluoromethane plus 1,2-dichlorotetrafluoroethane systems are presented. The critical locus of these systems is illustrated and the composition dependence of the critical parameters is discussed.. |

2. | M. Ashizawa, Y. Higashi, M. Uematsu, K. Watanabe, GENERALIZED REPRESENTATION OF VAPOR-PRESSURE CURVE FOR HALOGENATED HYDROCARBONS., 1987.01, The approach to the generalized representation of vapor-pressure curve is discussed on the basis of the experimental data of vapor pressure for eight halogenated hydrocarbons. With respect to the functional form of the generalized representation of vapor-pressure curve, the Pitzer expansion based on the principle of corresponding states with acentric factor was adopted. The coefficients in the representation have been determined by the least squares fitting to the experimental vapor pressure data for eight halogenated hydrocarbons mentioned above. The proposed generalized representation reproduces most of these data within a pressure deviation of plus or minus 1. 0%.. |

3. | Yukihiro Higashi, M. Uematsu, K. Watanabe, ASSESSMENT OF THE PREDICTIVE METHODS OF THE CRITICAL PARAMETERS FOR BINARY REFRIGERANT MIXTURES., 1987.01, The assessment of the predictive methods of the critical parameters is discussed on the basis of the comparison with the experimental results of our own critical parameters for the binary refrigerant mixtures, i. e. , the R 12(dichlorodifluoromethane; CCl//2F//2) plus R 22 (chlorodifluoromethane; CHClF//2) system, the R 22 plus R 114 (1,2-dichloro-1,1,2,2-tetrafluoroethane; CClF//2CClF//2) system, and the R 13B1 (bromotrifluoromethane; CBrF//3) plus R 114 system. The predictive method by Li for the critical temperature, that by Chueh-Prausnitz for the critical temperature and critical molar volume, that by Kreglewski-Kay for the critical pressure, that by Soave-Redlich-Kwong equation (SRK equation) as well as that by Peng-Robinson equation (PR equation) are discussed. Due to these comparisons, it becomes clear that it is difficult to predict the critical parameters for the binary refrigerant mixtures consistency by the predictive methods ever reported.. |

4. | M. Okada, T. Shibata, Y. Sato, Y. Higashi, Surface tension of HFC refrigerant mixtures, Proceedings of 1997 13th Symposium on Thermophysical Properties, 1999.01, The surface tension of several refrigerant mixtures was measured and correlated. The measurements were conducted using the differential capillary rise method (DCRM) under conditions of coexistence of the sample liquid and its saturated vapor in equilibrium. The temperature range covered was from 273 to 323 K. The resulting data were represented by a mixing rule using mass friction based on the van der Waals correlation.. |

5. | Katsuyuki Tanaka, Yukihiro Higashi, Measurements of the surface tension for the R290 + R600a mixtures, 3rd Asian Conference on Refrigeration and Air-Conditioning, ACRA 2006, 2006.01, The surface tension of the R290 + R600a mixture has been measured by the differential capillary-rise method. For measuring the binary system, the apparatus was modified to determine the composition of the sample. Seventeen data with a change of composition were obtained at 278.28 K. The experimental uncertainties of temperature and surface tension measurements are estimated to be within 20 mK and 0.2 mN·m^{-1}, respectively. The present data are compared with REFPROP ver.7.0 calculations [1]. As for composition dependence, the present data show different behavior against to REFPROP ver.7.0 calculations. Three kinds of mixing rules were tested for representing the composition dependence of the present data. It is found the simple mixing rule by mole fraction is effective for the R290 + R600a mixture.. |

6. | Katsuyuki Tanaka, Kohei Takahashi, Keizo Kobayashi, Yukihiro Higashi, Surface tension of low GWP refrigerant mixtures, 5th Asian Conference on Refrigeration and Air Conditioning - Green Breeze from Asia: Frontiers of Refrigerants, Heat Transfer and System, ACRA 2010, 2010.01, The surface tension of mixtures including low GWP refrigerants, 50 mass % HFO-1234yf/50 mass % HFC-32 and 50 mass % HFO-1234ze(E)/50 mass % HFC-32, was measured by the differential capillary-rise method in the temperature range from 273 K to 323 K. On a basis of the present data, correlations were formulated as a function of temperature by the expression of van der Waals type. A mixing rule for the coefficients in correlations of pure components was discussed for representing the data of mixtures. It is found to be difficult for representing the data of mixtures by a simple mixing rule.. |

7. | Yukihiro Higashi, Ryo Akasaka, Measurements of vapor pressures and critical parameters for 1,1,1,3,3-pentafluoropropane (R 245fa), 7th Asian Conference on Refrigeration and Air Conditioning, ACRA 2014, 2014.01, The determination of the critical parameters as well as the measurements of vapor pressures was made for 1,1,1,3,3-pentafluoropropane (R 245fa: C_{3}H_{3}F_{5}). The critical temperature and critical density of R 245fa were determined by the direct observation of meniscus disappearance in consideration of the intensity of critical opalescence and meniscus disappearing level. The measurements of vapor pressures were carried out by the isochoric method. As for both of apparatus, temperature was measured with 25 Ω standard platinum resistance thermometer and thermometer bridge with an aid of ITS-90. The digital quartz pressure transducer and pressure indicator were used for the pressure measurements. And density was calculated from the sample mass and inner volume of pressure vessel. The experimental uncertainties of temperature, pressure, and density measurements are estimated within 20 mK, 1 kPa, and 0.1%, respectively. Twenty-nine vapor pressure data for R 245fa were obtained in the temperature range from 310 K to the critical temperature and pressure up to 3.59 MPa with individual two runs. On the basis of these vapor-pressure measurements, the correlation of vapor pressures was proposed. The comparison with the vapor-pressure data reported by other investigators was also made. The authors are greatly indebted to Kobe Steel Ltd., Japan, for financial support, and to Asahi Glass Co., Japan, for furnishing and analyzing the high purity sample. The authors greatly thank to Messrs S. Hayasaka, C. Shirai, and Y. Oohira who are the student of Iwaki Meisei University, for their valuable assistance in the experiment. This work was supported by Grant-in-Aid for Scientific Research (C) 24560240 and 24560243 from Japan Societry for the Promotion of Science.. |

8. | Yukihiro Higashi, Thermophysical property measurements for R1234yf + R1234ze(E) mixture, 24th IIR International Congress of Refrigeration, ICR 2015, 2015.01, Measurements of PρTx properties, saturated densities and critical parameters for low GWP refrigerant mixtures of 50.00 mass% R1234yf (2, 3, 3, 3-tetrafluoroprop-1-ene; CF_{3}CF=CH_{2}) + 50.00 mass% R1234ze(E) (trans-1, 3, 3, 3-tetrafluoroprop-1-ene; CF_{3}CH=CHF) system were measured with two types of isochoric methods. As for PρTx properties, 5 isochores were obtained in the range of temperatures from 310 K to 430 K, of pressures from 837 kPa to 6774 kPa, and of densities from 100 kg·m^{-3} to 900 kg·m^{-3}. As for the saturated densities, 9 saturated vapor densities and 6 saturated liquid densities were measured for temperatures from 354.622 K to 374.280 K and for densities between 219 kg·m^{-3} and 870 kg·m^{-3}. On the basis of the present data, the critical temperature T_{c} = 374.28 K, critical density ρ_{c} = 480 kg·m^{-3}, and critical pressure P_{c} = 3524 kPa for 50% R 1234yf + 50% R 1234ze(E) mixture were determined by the direct observation of meniscus disappearance.. |

9. | Chieko Kondou, Ryuichi Nagata, Noriko Nii, Shigeru Koyama, Yukihiro Higashi, Surface tension of low GWP refrigerants R1234ze(Z) and R1233zd(E), 24th IIR International Congress of Refrigeration, ICR 2015, 2015.01, R1234ze(Z) and R1233zd(E) are very recently under consideration as a potential candidate to replace R245fa that is widely used in organic Rankine cycles and high-temperature industrial heat pumps. The capillary constant and surface tension of saturated R1234ze(Z) and R1233zd(E) were measured across the temperature range from 274 K to 350 K using a measuring apparatus based on the differential capillary rise method. The measurement uncertainty in the surface tension was typically 0.3 mN m^{-1}. The experimental surface tension was well represented by a van der Waals type equation expressing the temperature dependence as, ω= 59.90 (1 - T_{r})^{1.237} for R245fa, ω= 56.57 (1 - T_{r}) ^{1.220} for R1234ze(Z), and ω= 61.95 (1 - T_{r}) ^{1.277} for R1233zd(E), where, ω and T_{r} are the surface tension in mNm^{-1} and the reduced temperature, T_{r} = T/T_{crit}. The critical temperatures T_{crit} are given as 427.01 K for R245fa, 423.27 K for R1234ze(Z) by Higashi et al. (2015), and 438.75 K for R1233zd(E) by Hulse et al. (2012). The constants and exponents are empirically determined by the least square mean method. The above correlations represent the experimental surface tension within ±0.13, ±0.21 mN m^{1}, and ±0.05 mN m^{-1} for R245fa, R1234ze(Z), and R1233zd(E), respectively.. |

10. | Chieko Kondou, Yukihiro Higashi, Surface tension measurement for low GWP refrigerants HFO-1123 and HCFO-1224yd(z), 1st IIR International Conference on the Application of HFO Refrigerants, HFO 2018, 2018.01, By a differential capillary rise method, liquid-vapor interface surface tension was measured for new candidates of next generation refrigerant HFO-1123 and HCFO-1224yd(Z) at temperatures from 266 K to 304 K and from 266 K to 340 K, respectively. The repeatability and reproducibility of the measurement method were checked with HFC-134a and HFC-32. The propagated uncertainty in surface tension was estimated to be within ±0.2 mNm^{-1}. Based on the measured data, the Van der Waals type empirical correlations were proposed for HFO-1123 and HCFO-1224yd(Z), those are associated with the critical temperatures reported by Higashi and Akasaka. These empirical correlations agree with the measured surface tension data within the measurement uncertainty in the tested temperature range.. |

11. | Chieko Kondou, Taisuke Matsuzono, Taro Tsuyashima, Yukihiro Higashi, Surface tension measurement of low GWP refrigernat mixture HFO-1123/HFC-32, 9th Asian Conference on Refrigeration and Air-Conditioning, ACRA 2018, 2018.01, The global warming is now one of the serious international concern should be tackled worldwide. HFC refrigerants, such as R410A, are categorized as the long lived green-house gasses. This paper presents the surface tension measurement data of HFO-1123 with GWP less than 1, and a binary mixture HFO-1123/HFC-32. The capillary constant and surface tension of those are measured across temperature range from 267 K to 307 K by a differential capillary rise with a propagated uncertainty ±0.3 mN m^{-1}. Among the selected predicting methods, the correlations of Di Nicola et al. (2011) and Gharagheizi et al. (2012) show the best agreement to the measured surface tension of HFO-1123 alone. For HFO-1123/HFC-32, the correlation of Di Nicola et al. (2017) shows good agreement. To predict the surface tension HFO-1123/HFC-32, empirical correlation is proposed based on the measured data.. |

12. | Ryo Akasaka, Yukihiro Higashi, Shigeru Koyama, Development of the equation of state for HCFO-1224yd(Z) Detailed and extensive evaluation of the current equation and outlook for a new equation, 1st IIR International Conference on the Application of HFO Refrigerants, HFO 2018, 2018.01, The first fundamental equation of state for HCFO-1224yd(Z) was published in 2017. This equation shows reasonable accuracies in the density and vapor pressure at moderate temperatures and pressures. In addition, this equation is designed to exhibit physically correct behavior in extrapolated regions. At high temperatures and pressures, however, uncertainties in calculated properties would be higher, because at this time available experimental data are limited to restricted ranges. This paper demonstrates comparisons of the current equation to some available experimental data and evaluates behavior of the equation in the extrapolated regions.. |

13. | Naoya Sakoda, Jiang Shiheng, Masaya Nakazaki, Yasuyuki Takata, Yukihiro Higashi, Thermodynamic properties of binary mixtures of Trifluoroethene (HFO1123) + 2,3,3,3-Tetrafluoroprop-1-ene (HFO1234yf), 25th IIR International Congress of Refrigeration, ICR 2019, 2019.01, PvTx properties of a binary mixture of 50 mass% HFO1123 (trifluoroethene) + 50 mass% HFO1234yf (2,3,3,3-tetrafluoroprop-1-ene) were measured in the temperature range from 294 to 410 K, in the density range between 83 kg.m^{-3} and 905 kg.m^{-3}, and at pressures up to 8.1 MPa by an isochoric method, and the obtained data are compared with an equation of state (EOS) compiled in REFPROP 10.0. In addition, the critical parameters and saturated densities of the mixture were measured. Vapor-liquid equilibrium of HFO1123 + HFO1234yf was also measured at temperatures from 273 to 313 K by a recirculation method, and the binary interaction parameter of a cubic EOS was determined.. |

14. | Chieko Kondou, Jamal El Abbadi, Céline Houriez, Michel Masella, Yukihiro Higashi, Christophe Coquelet, Surface tension measurement and modeling work for new low GWP working fluids, 25th IIR International Congress of Refrigeration, ICR 2019, 2019.01, In this work, the surface tensions of some selected new low GWP (global warming potential) refrigerant mixtures containing HFOs (hydrofluoroolefins) were determined. The surface tension of the HFO-1123/HFC-32 was experimentally determined at temperatures from 265 K to near the critical points and with various compositions. Further, a model associating a cubic equation of state with the linear gradient theory was developed. Good agreement was observed between the experimentally obtained results and those obtained using the developed model.. |

15. | Kosuke Higashi, Chieko Kondou, Yukihiro Higashi, Shigeru Koyama, Performance analysis method for intermediated fluid type LNG vaporizers considering fluid properties, 25th IIR International Congress of Refrigeration, ICR 2019, 2019.01, LNG (Liquefied Natural Gas) vaporizer is widely used all over the world to vaporize LNG by using seawater, etc. as a heating source. Intermediated Fluid type LNG Vaporizer (IFV) is using intermediated fluid between LNG and heating source. Propane has been used as an intermediated fluid conventionally, but new refrigerants except for propane are required because usage environment was diversified recently. In this study, refrigerants substitute for propane applicable to IFV were selected as R32 and R410A. On the basis of some experimental formula, prediction of boiling and condensation heat exchange quantity in tube bundles was also carried out and it enabled to predict actual IFV vaporization quantity with plus or minus 2 percent accuracy. The prediction demonstrated that those selected refrigerants can increase the vaporization rate with IFV from the base line of propane.. |

16. | Céline Houriez, Michel Masella, Chieko Kondou, Yukihiro Higashi, Jamal El Abbadi, Christophe Coquelet, Molecular simulation for surface tension of new low GWP working fluids, 25th IIR International Congress of Refrigeration, ICR 2019, 2019.01, In this work, the calculated surface tension of selected new low GWP (global warming potential) pure compound refrigerants HFO (hydro-fluoro-olefin) is presented. Molecular simulation methods are used to calculate the surface tension of R-1123 (trifluoroethylene) and of R-1234ze(E) (trans-1,3,3,3-tetrafluoroprop-1-ene), as well as densities at saturation. The results obtained by molecular simulation are compared with recent experimental data.. |

17. | Y. Higashi, M. Uematsu, K. Watanabe, Direct determination of the critical parameters for several refrigerants, 16th International Congress of Refrigeration, 1983.07. |

18. | Y. Higashi, M. Uematsu, K. Watanabe, Direct determination of the critical parameters of fluids, Japan-U.S. Joint Seminar on Thermophysical Properties, 1983.09. |

19. | Y. Higashi, H. Hasebe, M. Uematsu, K. Watanabe, Study of the critical locus for non-azeotropic refrigerant mixtures, 第６回日本熱物性シンポジウム, 1985.11. |

20. | Y. Higashi, K. Watanabe, Thermophysical properties of nonazeotropic refrigerant blends, ASME paper, 86-WA/HT-72, 1986.05. |

21. | Y. Kabata, Y. Higashi, M.Uematsu, K. Watanabe, Measurements of the vapor-liquid coexistence curve for the R-152a + R-114 system in the critical region, 第７回日本熱物性シンポジウム, 1986.10. |

22. | Y. Higashi, M. Uematsu, K. Watanabe, Assessment of the predictive methods of the critical parameters for binary refrigerant mixtures, 1987 ASME-JSME Thermal Engineering Joint & Conference, 1987.04. |

23. | M. Ashizawa, Y. Higashi, M. Uematsu, K. Watanabe, Generalized representaion of vapor-pressure curve for halogenated hydrocarbons, 1987 ASME-JSME Thermal Engineering Joint Conference, 1987.04. |

24. | Y. Higashi, M. Uematsu, K. Watanabe, Thermodynamic behavior of the vapor-liquid coexistence curve for binary refrigerant mixtures, 17th International Congress of Refrigeration, 1987.05. |

25. | Y. Kabata, Y. Higashi, K. Watanabe, Correlation of the vapor-liquid coexistence curve for binary refrigerant mixtures, 17th International Congress of Refrigeration, 1987.05. |

26. | Y. Higashi, Correlation of the saturated densities for halogenated hydrocarbons and their mixtures, 2nd Asian Thermodynamic Properties Conference, 1989.10. |

27. | Y. Higashi, Procedure for the assessment of the critical parameters of fluids, 第１１回日本熱物性シンポジウム, 1990.10. |

28. | Y. Higashi, M. Okada, Measurements of the surface tension for CFC alternatives, 18th International Congress of Refrigeration, 1991.02. |

29. | M. Okada, Y. Higashi, T. Ikeda, T. Kuwana, Measurements of the surface tension for HCFC-142b and HFC-152a, 第１２回日本熱物性シンポジウム, 1991.11. |

30. | Y. Higashi, H. Imaizumi, S. Usuba, Measurements of the critical parameters for HFC-32, 第１３回 日本熱物性シンポジウム, 1992.09. |

31. | M. Okada, Y. Higashi, Measurements of the surface tension for HCFC-124 and HCFC-141b, 第１３回日本熱物性シンポジウム, 1992.09. |

32. | Y. Higashi, Vapor-liquid equilibrium for HFC-32/HFC-125 mixture, 第１４回日本熱物性シンポジウム, 1993.11. |

33. | M. Okada, Y. Higashi, Measurements of the surface tension for HFC-32 and HFC-125, 第１４回日本熱物性シンポジウム, 1993.11. |

34. | Y. Higashi, Vapor-liquid equilibrium, coexistence curve and critical locus for binary HFC-32/HFC-134a mixture, the 12th Symposium on Thermophysical Properties, 1994.09. |

35. | M. Okada, Y. Higashi, Experimental surface tension for HFC-32, HCFC-124, HFC-125, HCFC-141b, HCFC-142b and HFC-152a, the 12th Symposium on Thermophysical Properties, 1994.09. |

36. | T. Ikeda, K. Kanai, Y. Higashi, Determination of the critical locus for binary R-32/125 mixture, 第１５回 日本熱物性シンポジウム, 1994.10. |

37. | Y. Higashi, M.Funakura, Y. Yoshida, Vapor-liquid equilibrium for propane/iso-butane mixture, the International Conference, "CFCs, The Day After", 1994.11. |

38. | M. Okada, Y. Higashi, Surface tension correlation for HCFCs and HFCs, the International Conference, "CFCs, The Day After", 1994.11. |

39. | H. Sato, Y. Higashi, N. Kagawa, M. Okada, Y. Takaishi, K. Fujii, JAR Refrigerant database and thermodynamic tables project, Asia-Pacific Conference on the Built Environment, Singapore, ASHRAE(1995), 1995.02. |

40. | Y. Higashi, Vapor-liquid equilibrium, coexistence curve and critical locus for binary R-32/125 mixture, 19th International Congress of Refrigeration, 1995.04. |

41. | Y. Higashi, T. Ikeda, Critical parameters for 1,1,1-trifluoroethane(R-143a), 4th Asian Thermophysical Properties Conference, 1995.09. |

42. | Y. Higashi, Vapor-liquid equilibrium and critical point for the R32/R125/R134a mixture, AIChE 1996 Spring National Meeting, 1996.04. |

43. | M. Okada, T. Shibata, Y. Sato, Y. Higashi, Surface tension of HFC Refrigerant mixtures, 13th Symposium on Thermophysical Properties, 1997.06. |

44. | Y. Higashi, Critical locus for binary and ternary HFC refrigerant mixtures, 13th Symposium on Thermophysical Properties, 1997.06. |

45. | Y. Higashi, Critical locus measurement for the binary difluoromethane (R32) + propane (R290), 14th Symposium on Thermophysical Properties, 2000.06. |

46. | C. D. Holcomb, Y. Higashi, S. L. Outcult, Design of a small-volume, quad-cell, dual-method, dew/bubble point apparatus, 14th Symposium on Thermophysical Properties, 2000.06. |

47. | Y. Higashi, K. Suzaka, K. Fujii, Vapor-liquid equilibrium measurements for the R410A and R407C mixtures in the temperature range between 263.15 K and 293.15 K, Thermophysical Properties and Transfer Processes of New Refrigerants, IIR Conference, 2001.09. |

48. | H. Sato, N. Kagawa, Y. Takaishi, Y. Higashi, C. Yokoyama, K. Fujii, K. Murakami, M.J.Assael, M. Noguchi, H. Tanabe, M. Fukushima, K. Takigawa, Currently reliable property values and simple equationfor pure hydrofluorocarbons, 9th International Refrigeration and Air Conditioning Conference, 2002.07. |

49. | Y. Higashi, Experimental determination of the critical locus for the difluoromethane (R32) and propane (R290), International Symposium on Molecular Thermodynamics and Molecular Simulation, 2003.05. |

50. | Y. Higashi, Determination of the critical parameters for propane (R290) and isobutane (R600a), 15th Symposium on Thermophysical Properties, 2003.09. |

51. | Y. Higashi, Measurements of saturated densities and critical parameters for the propane + isobutane system, Natural Working Fluids 2004: 6th IIR-Gustav Lorentzen Conference, 2004.10. |

52. | E. Iwasaki, Y. Higashi, M. Okada, Measurements of the surface tension and density for ethanol and 1-butanol, Natural Working Fluids 2004: 6th IIR-Gustav Lorentzen Conference, 2004.10. |

53. | Y. Higashi, Composition dependence of the critical parameters for the binary mixtures of R32+R290, R32+R600a, and R290+R600a system, Thermophysical Properties and Transport Processes of Refrigerants, 2005.09. |

54. | K. Tanaka, Y. Higashi , Measurements of the surface tension for the R290 + R600a mixture, 3rd Asian Conference on Refrigeration and Air-Conditioning, 2006.03. |

55. | K. Tanaka, Y. Higashi, Y. Kayukawa, K. Fujii, Vapor-liquid equilibrium measurements for the binary and ternary mixtures of R290, R600a, and R32 at temperatures between 260 K and 330 K, 16th Symposium on Thermophysical Properties, 2006.06. |

56. | K. Tanaka, Y. Higashi, Measurements of the surface tension for some alcohols, 16th Symposium on Thermophysical Properties, 2006.06. |

57. | Y. Higashi, K. Tanaka, R. Akasaka , Y. Kayukawa, K. Fujii , Vapor-liquid equilibrium measurements for the CO2 + R290 mixture, 22nd International Congress of Refrigeration, 2007.11. |

58. | K. Tanaka, G. Takahashi, A. Kitayama, Y. Higashi, Calorimeter for measuring the isobaric specific heat capacity of natural refrigerants, 8th IIR-Gustav Lorentzen Conference on Natural Working Fluids, 2008.05. |

59. | K. Tanaka, Y. Higashi, Thermodynamic properties of HFO-1234yf(2,3,3,3-tetrafluoropropene), 3rd IIR Conference on Thermophysical Properties and Transport Processes of Refrigerants, 2009.06. |

60. | R. Akasaka, K. Tanaka, Y. Higashi, A practical equation of state for 2,3,3,3-tetrafluoropropene (HFO-1234yf) to calculate saturation properties, 17th Symposium on Thermophysical Properties, 2009.06. |

61. | G. Takahashi, K. Tanaka, Y. Higashi, Measurements of vapor pressure and isobaric specific heat capacity of 2,3,3,3-tetrafluoropropene (HFO-1234yf), 17th Symposium on Thermophysical Properties, 2009.06. |

62. | T. Ichikawa, K. Tanaka, Y. Higashi, Measurements of the critical parameters and vapor-liquid coexistence curve for 2,3,3,3-tetrafluoropropene, 17th Symposium on Thermophysical Properties, 2009.06. |

63. | K. Takahashi, K. Tanaka, Y. Higashi, Measurements of the surface tension for 2,3,3,3-tetrafluoropropene (HFO-1234yf), 17th Symposium on Thermophysical Properties, 2009.06. |

64. | K. Tanaka, K. Kobayashi, Y. Higashi, Pressure-Volume-Temperature relationship for HFO-1234ze(E) + HFC-32 mixture, 2010 International Symposium on Next-generation Air Conditioning and Refrigeration Technology, 2010.02. |

65. | Y. Higashi, Thermophysical properties of HFO-1234yf and HFO-1234ze(E), 2010 International Symposium on Next-generation Air Conditioning and Refrigeration Technology, 2010.02. |

66. | K. Tanaka, K. Takahashi, K. Kobayashi, Y. Higashi, Surface Tension of Low GWP Refrigerant Mixtures, 5th Asian Conference on Refrigeration and Air-Conditioning, 2010.10. |

67. | M. Akatsu, K. Tanaka, Y. Higashi, Measurements of Saturated Densities and Critical Parameters for the Binary HFC-1234yf + HFC-32 Mixtures, 23rd International Congress of Refrigeration, 2011.10. |

68. | K. Kobayashi, K. Tanaka, Y. Higashi, Measurements of PρTx properties for the Binary HFC-1234yf + HFC-32 Mixtures, 23rd International Congress of Refrigeration, 2011.10. |

69. | K. Tanaka, Y. Higashi, R. Akasaka , Thermodynamic-Property Modeling of HFO-1234ze(E) + HFC-32 Mixtures for Evaluating Cycle Performance, 23rd International Congress of Refrigeration, 2011.10. |

70. | R. Akasaka, Y. Higashi, A Predictive Model for the Thermodynamic Properties of Mixtures, 18th Symposium on Thermophysical Properties, 2012.06. |

71. | Y. Higashi, Measurements of Thermodynamic Properties and Critical Parameters for the Propylene (R 1270) + R 32 Mixture, 18th Symposium on Thermophysical Properties, 2012.06. |

72. | Y. Higashi, S. Hayasaka, S. Ogiya, Measurements of PVT Properties, Vapor Pressures and Critical Parameters for Low GWP Refrigerant R-1234ze(Z), 4th IIR Conference of Thermophysical Properties and Transfer Processes of Refrigeration, 2013.06. |

73. | R. Akasaka, Y. Higashi, S. Koyama, A Fundamental Equation of State for Low GWP Refrigerant HFO-1234ze(Z), 4th IIR Conference of Thermophysical Properties and Transfer Processes of Refrigeration, 2013.06. |

74. | Y. Higashi, R. Akasaka, Measurements of Vapor Pressures and Critical Parameters for 1,1,1,3,3-Pentafluoropropane (R 245fa), 7th Asian Conference on Refrigeration and Air Conditioning (ACRA 2014), 2014.05. |

75. | R. Akasaka, Y. Higashi, A Thermodynamic Property Model for the R 134a/245fa Mixtures, 15th International Refrigeration and Air Conditioning Conference, 2014.07. |

76. | Y. Higashi, Thermophysical property measurements of PrT properties, vapor pressures, saturated densities, surface tension, and critical parameters, Workshop of Low GWP Refrigerants: Joint International Research Opportunities, 2014.12. |

77. | Y. Higashi, C. Shirai, R. Akasaka, Measurements of PρT Properties, Vapor Pressures, Saturated Densities, and Critical Parameters for R1243zf, 19th Symposium on Thermophysical Properties, 2015.06. |

78. | R. Akasaka, Y. Higashi, A. Miyara, J. Steve Brown, S. Koyama, A Preliminary Equation of State for 3,3,3-Trifluoroprop-1-ene (R1243zf), 19th Symposium on Thermophysical Properties, 2015.06. |

79. | R. Nagata, C. Kondou, N. Nii, S. Koyama, Y. Higashi, Measurements of Surface Tension for Refrigerants R245fa, R1243zf, R1234ze(Z), and R1233zd(E), 19th Symposium on Thermophysical Properties, 2015.06. |

80. | C. Shirai, Y. Higashi, R. Akasaka, Thermophysical Property Measurements gor the Binary and Ternary Mixtures Composed of HFOs, 19th Symposium on Thermophysical Properties, 2015.06. |

81. | C. Kondou, R. Nagata, N. Nii, S. Koyama, Y. Higashi, Surface Tension of Low GWP Refrigerants R 1234ze(Z) and R 1233zd(E), 24th International Congress of Refrigeration, 2015.08. |

82. | Y. Higashi, Thermophysical Property Measurements for R 1234yf + R 1234ze(E) Mixture, 24th International Congress of Refrigeration, 2015.08. |

83. | Y. Higashi, Thermophysical property measurements for new refrigerants and their mixtures, 2nd Workshop of Low GWP Refrigerants: Joint International Research Opportunities, 2015.09. |

84. | Y. Higashi, Determination of the critical point for low GWP refrigerants and their mixtures, Workshop on Thermal Issues for Hydrogen and Related Energy Systems, 10th International Hydrogen Energy Development Forum 2016, 2015.09. |

85. | Y. Higashi, R. Akasaka, Measurements of Thermodynamic Properties for R1123 and R1123+R32 Mixture, 16th International Refrigenration and Air Conditioning Conference, 2016.07. |

86. | Y. Higashi, Measurements of Vapor Pressures, Saturated Densities, and Criticala Parameters for R1224yd(Z), 11th Asian Thermophysical Properties Conference (ATPC), 2016.10. |

87. | Y. Higashi, S. Koyama, A. Miyara, R. Akasaka, C. Kondou, Fundamental research on next generation refrigerants for air conditioning system: assessment of thermophysical properties, heat transfer characteristics, and cycle performence, JRAIA International Symposium, 2016.12. |

88. | Y. Higashi, S. Koyama, A. Miyara, R. Akasaka, C. Kondou, Fundamental research on next generation refriegerants for air conditioning systems, Internaional Symposium on New Regrigerants and Environmental Technology 2016, Kobe, Japan, 2016.12. |

89. | T. Matsuzono, C. Kondou, Y. Higashi, S. Koyama, Surface Tension Measurements of Low GWP Refrigerants, 5th IIR Conference of Thermophysical Properties and Transfer Processes of Refrigeration, 2017.05. |

90. | N. Sakoda, Amitul MD Islam, S. Koyama, Y. Takata, Y. Higashi, Vapor Pressure and Critical Pressure Measurements of R1233zd(E) and R336mzz, 21nd European Conference of Thermophysical Properties, 2017.09. |

91. | Y. Higashi, Thermodynamic Properties of Next Generation Refrigerants, The 9th Asian Conference on Refrigeration and Air-conditioning(ACRA2018), 2018.06, [URL]. |

92. | C. Kondou, T. Matsuzono, T. Tsuyashima, Y. Higashi, Surface Tension Measurement of Low GWP Refrigerant Mixture HFO-1123/HFC-32, The 9th Asian Conference on Refrigeration and Air-conditioning(ACRA2018), 2018.06, [URL]. |

93. | C. Kondou, T. Matsuzono, Y. Higashi, Surface Tension Measurement of Low GWP Refrigerant Mixture HFO-1123/HFC-32 and HFO-1234ze(E)/HFC-32, the 17th International Refrigeration and Air Conditioning Conference, 2018.07, [URL]. |

94. | S. Koyama, T. Miyazaki, J. Hirayama, N. Takata, Y. Higashi, Performance Evaluation of Heat Pump Cycle using Low GWP Refrigerant Mixtures of HFC-32 and HFO-1123, the 17th International Refrigeration and Air Conditioning Conference, 2018.07, [URL]. |

95. | C. Kondou, T. Tsuyashima, Y. Higashi, Surface Tension Measurement for Low GWP refrigerants HFO-1123 and HCFO-1224yd(Z), 1st IIR International Conference on the Application of HFO Refrigerants, 2018.09, [URL]. |

96. | R. Akasaka, Y. Higashi, S. Koyama, Development of the Equation of State for HCFO-1224yd(Z): Detailed and Extensive Evaluation of the Current Equation and Outlook for a New Equation, 1st IIR International Conference on the Application of HFO Refrigerants, 2018.09. |

97. | Y. Higashi, Thermodynamic Property Measurements of New Refrigerants and Their Mixtures, International Workshop on Environmental Engineering 2019 (IWEE2019), 2019.06, [URL]. |

98. | Thu Kyaw, K. Takezato, S. Senba, U. C. A. Perera, N. Takata, Y. Higashi, T. Miyazaki, Heat pump cycle performance using low GWP ternary mixture of R32, R1234yf and R744, International Workshop on Environmental Engineering 2019 (IWEE2019), 2019.06, [URL]. |

99. | N. Sakoda, Jiang SHIHENG, M. Nakazaki, Y. Takata, Y. Higashi, Thermodynamic properties of binary mixtures of Trifluoroethene (HFO1123)+2,3,3,3-Tetrafluoroprop-1-ene(HFO1234yf), The 25TH IIR International Congress Of Refrigeration (ICR2019), 2019.08, [URL]. |

100. | Celine HOURIEZ, Michel MASELLA, C. Kondou, Y. Higashi, Jamal EL ABBADI, Cristophe COQUELET, Molecular Simulation for Surface Tension of New Low GWP Working Fluids, The 25TH IIR International Congress Of Refrigeration (ICR2019), 2019.08, [URL]. |

101. | C. Kondou, Jamal EL ABBADI, Celine HOURIEZ, Michel MASELLA, Y. Higashi, Christophe COQUELET, Surface Tension Measurement and Modeling Work for New Low GWP Working Fluids, The 25TH IIR International Congress Of Refrigeration (ICR2019), 2019.08, [URL]. |

102. | M. Nagaoka, K. Yosiura, N. Sakoda, Y. Higashi, Y. Takata, Thermodynamic Properties Measurements of HFE356mmz for High-temperature Heat Pump Systems, The Asian Thermophysical Properties Conference in 2019 (ATPC 2019), 2019.10, [URL]. |

103. | N. Sakoda, Y. Higashi, PVT Properties, Saturated Densities and Critical Parameters for a Low-GWP Refrigerant Mixture R448a, The Asian Thermophysical Properties Conference in 2019 (ATPC 2019), 2019.10, [URL]. |

Unauthorized reprint of the contents of this database is prohibited.