Among several low-GWP refrigerants, R1234yf, R1234ze(E) ，R1234ze(Z) ，HFO-1243zf，R1224yd(Z) ，R1233zd(E) ，R1336mzz(E) ，R1336mzz(Z) and HFO-1123 were intensively reviewed in the present work. These refrigerants are candidates to be used in more efficient refrigerators, air conditioners, high temperature heatpumps and ORC systems to conserve energy resources. Since large numbers of studies on their thermophysical properties have been conducted for more than ten years, thermodynamic equations of state for them were developed and installed in the latest version of REFPROP（ver. 10.0). In the present work,literature data available at present were discussed by tabulating and compared with those equations of state.

The effects of pH on the protein solubility, film-forming ability of lizardfish viscera (stomach and intestines) and physico-chemical properties of the biodegradable films were investigated. The new approach could successfully yield protein-based films from lizardfish viscera at a narrow pH range (2 - 4, and 13) without the need for a protein extraction process. All films were observed to completely block UV light transmission. Films at pH 13 were hydrophilic, exhibited the lowest mechanical strength, highest deformability, and greatest yellowish color, while films at pH 4 were mechanically stronger, slightly deformable and showed superior light transmission barrier properties compared to other film samples. The substantial contribution of disulfide bonds to the formation of the three-dimensional network of films at pH 4 was confirmed by SDS-PAGE. Thus, films from lizardfish viscera can be utilized as a renewable packaging material in food systems.

When moisture in food freezes, the growth of ice crystals caused damage to food structure. It was reported that the fine and homogeneous ice crystals could be formed when accidental supercooling during freezing. In this study, a sample of mung bean sprout was intentionally supercooled and frozen by slow freezing after blanching. The effects of the freezing conditions on mung bean sprout after thawing and the size of ice crystals were investigated. As a result, the freezing in still air at －10 ℃ after blanching was easy to occur supercooling of mung bean sprout, and the textural property of thawed mung bean sprout was similar to unfrozen sample.

In order to reduce the global warming potential of refrigerants used in air-conditioning systems and refrigerators, several new low GWP refrigerants in which HFO refrigerant is mixed with conventional HFC refrigerant have been proposed. Ensuring the reliability of the compressor sliding part is one of the issues in applying low GWP refrigerant to the systems. Around the sliding part there are refrigerant, refrigeration oil, and extreme pressure agent contained in the oil. By clarifying the effect of these element on the tribological characteristics, it can be reflected in the design of the sliding element. Therefore, we selected R 32, R 1234yf and several HFC / HFO mixed refrigerants, and carried out seizure resistance test in the liquid refrigerant and refrigeration oil, analysis of sliding surface reaction film, and measurement of viscosity of refrigeration oil with dissolved liquid refrigerant.

The critical parameters for cis−1,3,3,3−tetrafluoro−propene (HFO-1234ze(Z)) were measured by the meniscus observation. Firstly, menisci were observed roughly along three isochoric lines in the density range from 449 kg×m^-3 to 478 kg×m^-3, i.e. near the critical density reported in the literature. Secondly, menisci were observed precisely near the critical temperature along six isochoric lines in the density range from 454 kg×m^-3 to 470 kg×m^-3. The critical density, critical temperature and critical pressure of HFO-1234ze(Z) were determined to be 459 ± 3 kg×m^-3, 423.34 ± 0.03 K and 3521 ± 6 kPa, respectively.

The surface tension was measured for several low-GWP refrigerants, which are grouped in HCFO and HFO, by a differential capillary rise method. The comparison between measured data and calculated value by REFPROP 10.0 were reviewed. The review results suggest that the uncertainty in surface tension calculated by REFROP 10.0 are not negligibly small for R1224yd(Z) and R1336mzz(Z). Based on the measured data and calculated orthobaric densities, “Parachor” was identified for each refrigerant. Among the measured refrigerants, the parachor of only R1336mzz(E) showed obvious temperature dependence, which means there could be an inconsistency between orthobaric densities and surface tension.

HFO refrigerants are attracting worldwide attentions as alternatives with low global warming potential (GWP) to reduce environmental impacts. Physical property data of candidate refrigerants are important to evaluate performance of heat pump systems. To predict one of physical property surface tension, molecular orbital (MO) simulation and molecular dynamics (MD) simulation were performed for ethylene, which is a base of HFO refrigerants, and HFO refrigerant HFO1123. The difference between saturated liquid and vapor densities and surface tension of ethylene were underestimated at higher reduced temperatures. This can be improved with the validation of intra-molecular force field at higher temperatures. On the other hand, the saturated density of HFO1123 well agreed with the measured. However, the simulated surface tension was obviously overestimated at lower temperatures. To improve the simulation for HFOs, finding a potential needed to be modified would be important.

This study experimentally investigated the void fraction characteristics of R32 in square minichannels, which simulated a multiport tube, via image analysis. The test square minichannels consist of multiport minichannels with dimensions of 1.0×1.0 mm. The experiments were conducted using R32 as a test fluid with a mass velocity range of 30–400 kgm^-2s^-1, vapor quality range of 0.1–0.9, and at a saturation temperature of 40 °C. The void fraction measurement was conducted via image analysis based on the flow patterns observed using a high-speed camera and defined by the ratio of the pixels of the vapor and liquid phases. The time-averaged void fraction decreased with decreasing mass velocity at the same vapor quality for G ≤ 50 kgm^-2s^-1. The homogeneous flow model was suitable for higher mass velocities, whereas the separated flow model was suitable for lower mass velocities except at the lowest vapor quality. The void fraction was predicted within mean absolute deviation of 0.04 by separated flow model.

This study investigated condensation heat transfer characteristics outside a horizontal microscopic-grooved tube with 3 dimention structure and developed the predicted correlation. The test tube was an outer diameter of about 19 mm, R 134a, R 245fa, R 1234ze (E), and R 1234yf were used as the test refrigerants, were clarified the fundamental characteristics of condenstion heat transfer and were developed the predicted correlation by the experiment with a single tube and a simulating inundation using the liquid supply. In the single tube experiment, it was clarified that large effects of condensation heat transfer on the area magnification ratio, the ratio of surface tension and liquid density σ /ρliq and the liquid thermal conductivity. In the simulating inundation experiment, it was revealed that the condensation heat transfer of microscopic-grooved tube with 3 dimention structure was dominated by the convection heat transfer in the laminar region, and the effect of the film Reynolds number on the condensation heat transfer characteristics was small. The predicted correlation for condensation heat transfer coefficient outside a horizontal microscopic-groovedenhanced tube with 3 dimention structure can be correlated from -17 to + 23% was proposed based on the experimental results.

In this study, the boiling heat transfer characteristics inside a horizontal smooth tube of low-GWP refrigerants R1224yd (Z), R1233zd (E), R1336mzz (E) and R1336mzz(Z) are expected to be used as alternative refrigerants to R245fa used in high-temperature heat pump and binary power generators systems using organic Rankine cycle were experimentally clarified. The smooth tube used has an outer diameter of 9.52 mm and an inner diameter of 8.40 mm, and a heat flux range of 2–15 kWm^-2, a mass velocity range of 50–300 kgm^-2s^-1, and a saturation temperature of 40 °C was conducted in this experiment. The boiling heat transfer coefficient was measured, and the applicability of the correlation proposed in the previous research was verified. It was found that the heat transfer coefficients were generally lower in the high mass velocity range than the previous correlations. Therefore, the new correlation for boiling heat transfer coefficient was proposed based on the experimental values of R245fa, R1224yd (Z), R1233zd (E), R1336mzz (E) and R1336mzz (Z) in the experiment. The new present correlation showed high prediction accuracy not only for our experimental values but also for the experimental values of low-pressure refrigerants such as R114 and R123 reported by other researchers.