This article begins to describe some general thermodynamic behaviors of mixtures as well as the overview of the previously reported feasibility studies related to the performance test and the cycle analysis of the reversed Rankine cycle system with refrigerant mixtures. The current state of the art for the equilibrium and non-equiliburium properties of nonazeotropic refrigerant mixtures is then reviewed.
The present review shows that the absolute quantity and quality of information about the thermophysical properties are still limited. Concerning the equilibrium properties, vapor-liquid equilibrium data are available for quite a few refrigerant mixtures, but most of them are in the limited range of temperature and pressure. PVTx data for several refrigerant mixtures are also available but scarce with respect to the calorimetric and other properties. Experimental studies concerning the non-equilibrium properties, on the other hand, have recently begun to reveal the temperature, pressure and composition dependence of the viscosity and thermal conductivity in gaseous phase for several refrigerant mixtures. It is, therefore, concluded that further experimental studies of both equilibrium and non-equilibrium properties should be made so as to develop estimation methods to correlate mixture properties more precisely as well as to promote practical applications of the nonazeotropic refrigerant mixtures in the advanced vaporcompression refrigeration and heat pump cycles.

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In the blood of winter polar fish an antifreeze glycoprotein (AFGP) occurs which acts to protect the fish from freezing to death. The AFGP has a unique hydrophilic hydrophobic conformation, involved in non-colligative depression of the freezing temperature of water without altering the melting point of ice. This phenomenon is reportedly a reflection of the ice crystal growth inhibition by the adsorption of the AFGP onto a-axial surfaces of the ice crystal. The authors, on the other hand, have developed an enzymatically modified protein (EMG-12) by covalent attachment of leucine dodecyl ester to the C-terminal position of gelation with the aid of a reverse reaction catalyzed by a protease. EMG-12, having a hydrophilic-hydrophobic structure, is highly surface-active and acts to stabilize a supercooling state of water by antinucleation. Discussions are made on similarities and dissimilarities of structure-function relationships of these natural and artificial antifreeze proteins. The significance of using them as antifreeze agents is also discussed.

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Squid ( Todarodes pacificus) , which is one of the main Japanzse coastal fish , was frozen under commercial condition after catch immediately and stored at -18 , -23 , -30 °C and 40 °C for 12 months. During storage the quality was measured by determining amount of free drip , water-holding capacity of muscle , weight ratio of cooking loss , histoligical feature of frozen and thawed muscle , and organoleptic test at regular intervals , each 2 months. Storage life of frozen squid was 12 months at below -18 °C.

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An equation of state for Refrigerant 502 has been proposed in a wide range of temperatures 170 to 500 K and of pressures 0 to 15 MPa, which corresponds to a density variation from 0 to 1686 kg/m³ including both the gaseous and liquid state. The equation was formulated based on the experimental data of PVT properties, saturated liquid density and vapor-liquid coxistence curve near the critical point which we evaluated to be reliable. The equation is expressed by reduced specific Helmholtz function. The thermodynamic consistency of the proposed equation of state is confirmed by examining behavior of calculated values concerning isochoric specific heat capacity, isobaric specific heat capacity and speed of sound with respect to temperature and pressure dependences of those properties.

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The aqua-solvent emplyed in this experiment is Calcium chloride, Sodium chloride, Magnesium chloride. Snow particle diameter are 0.34, 0.51, 1.12 mm. The melting of the snow is carried out in the condition of the thermodynamic non-equilibrium state. The temperature in the melting field including both the aqua-solvent and the snow particle suddenly decreases in a few seconds, and then, the melting field attains a uniform temperature indicating the equilibrium state at the prescribed concentration. The melting coefficient has been obtained experimentally which is corresponds to the melting amount per unit concentration, unit area, and unit time.

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In the cryoelectronics field where the helium gas is utilized as a working field, rotary-type and reciprocating-type compressors are popular for the discharge capacity of less than 200Nm³/h and screw-type compressor for a larger capacity.
In this study, scroll-type fluid machinery, featuring both high efficiency and high reliability, is applied to a helium compressor with the discharge capacity of 50 Nm³/h. Experimental investigations are performed about oil injection cooling methods and improvement of the compression efficiency.
As a result, a volumetric efficiency of 92 % and an overall adiabatic efficiency of 79 % are obtained under the condition of a theoretical compression ratio of 5.2 by a developed scroll compressor with a nominal motor output 2.2 kW.
At the same time an effective cooling method with a single oil injection port is obtained.

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Heat generating devices and heat recovery systems are desired to control the heat flow and the temperature, contrary to the prior thermo-siphon uncontrolable heat flow. Then, authors have developed a heat flow controlable heat exchanger having a bubble pump mechanism without movable par t. The heat exchanger is consisted of evaporator, condenser, vapor passage pipe, liquid return pipe with a reverse-U type pipe, and heater located on the reverse pipe. Further the system encloses evaporating liquid and is possible to control heat flow between the evaporator to the condenser by adjusting the heater power. This paper presents experimental results on the system. The following results are obtained. (1) The heat exchanger can control heat flow between the evaporator to the condenser by adjusting the heater input which is smaller about 1/20 the above heat flow. (2) The complex heat flow controlable heat exchanger system is possible to control the output temperature by changing its operating heat exchanger number. (3) This heat exchanger is useful to the heat recovery at the room, the temperature control at the space, and the system joining heat storage system.

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Heat transfer coefficient in an open thermosyphon is very small, because the flow in the thermosyphon is confined to a narrow space by the wall of tube with a closed bottom end. Therefore, augmentation of heat transfer due to air injection from the bottom has been suggested. The heat transfer is enhanced by the stirring action of rising bubbles. In response to this, the authors performed an experimental investigation of this subject. Seven test tubes with different diameter and length were employed, and water, ethyl alcohol and ethylene glycol were used as test liquids. The heat transfer coefficients were measured and the effects of air injection rate, tube diameter, tube length and liquid properties were examined. And experimental correlations were presented by using dimensional analysis.

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The peculiar features of the melting of ice around a horizontal circular cylinder, the shape of icewater interface and the flow of the melt, were observed and discussed. And, it was shown that the temperature of the cylindrical heater surface was maintained constant at respective values before and after inversion of the flow direction of melt.

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