Vitrification is an alternative to customary approaches to cryopreserve cell, tissue and organ. In this method, ice formation can be prevented by a combination of high solute concentration and rapid cooling, a solution become glassy without ice crystalline formation at temperatures below-115°C. The cell and tissue damage associated with ice formation is avoided, but thawing should be rapid enough to prevent ice growth during warming and they should be equilibrated with the vitrification medium without injury.
This approach has been extensively studied in the past few years, and has the potential to be an alternative approach to the cryopreservation of a wide range of biological systems.

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Computer simulation analysis was made for theoretical thermal characteristics of two stage compression two stage condensation cycle, which is one of the basic cycles of multistage heat pump systems, and steady state solution of convergence was obtained, component characteristics being replaced by simplified experimental models. Also experiments were performed by cycle simulation system using R22 as a working fluid and the steady results of measurements were obtained. Useful information for the design and estimation of multistage heat pump systems were obtained, by the consideration of the effect of the change for the performance parameters of condensation temperature, working fluids, condensation pressure ratio on the cycle characteristics.

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Numerical analysis was performed for the absorption of carbon-dioxide gas into a condensate film. A condensate film flowing on a vertical surface under the influence of the combined effects of the vapor shear and gravity was chosen as a model problem. Convective flux towards the wall surface played a significant role in the absorption characteristics. Concentrations of the carbon-dioxide and bicarbonate ion in the film increased as the condensation proceeded. The difference between the two concentrations at a same longitudinal position decreased as the condensation proceeded. Ionic dissociation equilibrium state, however, was not observed in the range analyzed. Resistivity of the condensate film was much larger for higher vapor velocity with smaller vapor-to-wall temperature difference, taking larger value for lower concentration of carbon-dioxide in the vapor phase. In addition, the resistivity became more sensitive to the condensing condition as the carbon-dioxide concentration in the vapor phase increased.

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The expander-compressor is one of the most important parts of a Rankine cycle-vapor compression heat pump system. Since simplicity and ease of sealing are desired, a novel design incorporating an "inertial-type free piston expander-compressor" is presented in this paper. It is composed of one cylinder and one free piston, and the inertia of the piston is used to transmit energy. One numerical model, called the multinode model, is used to calculate the heat transfer coefficient between the gas and the cylinder wall, which is in turn input to another model, called the three-node model, by which the coefficient of performance is calculated. The estimated performance is sufficient for practical applications.

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Heat transfer performance of forced convective boiling in high temperature generator was experimentally studied using an actual absorption chiller/heater. Measurements were made at six locations, three different levels on a couple of laterally separated lines, for the fluid rising along the rear wall of the high temperature generator furnace. Fluids tested were water and lithium bromide aqueous solution. System pressures were maintained at 96 and 24 kPa, and firing rates were changed from 100 to 40 % of the full load of the machine.
Through the experiments, thermodynamic states of both of the fluids were in subcooled region at the lower and middle locations and in saturated region at the upper location. It can be suggested that saturated boiling occurs at comparatively narrow area, located at the upper zone of heat transfer surface of the generator, while forced convective heat transfer and subcooled boiling appear at the remaining broad area. Enhancement of heat transfer due to saturated boiling was not pronounced for lithium bromide aqueous solution than for water.

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For the purpose of development of high performance absorption chiller/heater utilizing lithium bromide aqueous solution as working fluid, it is the most effective to improve the performance of absorber with the largest heat transfer area of the four heat exchangers.
This paper introduces two kinds of double fluted tubes for the absorber of absorption chiller/heater. Arm tube and floral tube have about 40% higter heat transfer performance than the plain tube conventionally used in absorber. The former is manufactured by double drawbench process, while the latter by single drawbench process. Therefore, floral tube is expected to realize both high heat transfer perfoemance and low cost.

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Scroll compressors have excellent fundamental features such as high efficiency, high reliability, low vibration and low noise, so scroll compressors have been recently used to heat pump and automotive air conditioners. Furthermore, the development to low temperature applications such as a refrigeration unit has been taken.
In the low temperature applications, as the suction gas pressure is very low the compression ratio is very high, and as a result the discharge gas goes to very high temperature. In order to lower discharge gas temperature, refrigerant liquid has been injected into compression pockets. Further, in case of both low temperature usage and heat pump, in order to cool down the motor refrigerant liquid bypass operating system has been adopted.
We have theoretically and experimentally studied the scroll compressor behavior in case of liquid refrigerant is existed in the compession pockets. In this paper, we describe these analytical and experimental results.

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The practical design method on the chain-like connected closed-type thermal storage tanks, which has capacity of 120 m³, has been clarified as follows;
1) The combination of two perforated plates are installed at the top and the bottom of every storage tank as a rectifier to obtain uniform velocity distribution. Pressure drop at each perforated plate set the same value as dynamic pressur of the upper stream. The rectifier indicates very high performance of uniformity, such as 0.03 to 0.14 level of standard deviations.
2) The estimation method for evaluating amount of the mixing volume in the storage tank are found out using the behabior of temperature response of the tank with stepwise change of inlet.
3) The Archimedean number define as inlet condition of the tank, namely Arin, will be kept larger than 0.5 to get the mixing volume less than 10% of the tank volume.
4) Around 0.1 of Arin gives the minimum tank wall volume, that is most economical design point.

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The purpose of this study is to develop the top heat mode thermosyphon that is very attractive means, for example, to accumulate directly the summer solar energy into the underground soil for the winter season. In this case, it can exclude the complex piping and mechanical pump to circulate the hot water absorbed the solar energy through the piping system buried in the soil layer.
The several ideas concerning the top heat thermosyphon had been proposed, however, there were few reports on the definite experiments. The authors have carried out the experimental study of the top heat mode thermosyphon, with a simple lifting pipe, which could draw the working liquid from the under condenser to the upper evaporator section.
The improvement of the main construction parts such as evaporator, lifting pipe, liquid reservoir trap and vapour nozzle have been performed in the present experiment in order to obtain the optimum operation range.

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The effect of alcoholic additives on surface tension of aqueous solutions of lithium bromide is investigated. As an additive, 1-hexanol, 1-heptanol, 1-octanol and 1-nonanol are selected. The surface tension of lithium bromide solution with alcoholic additives is predicted from hydration numbers of lithium bromide in aqueous solutions and surface tension of aqueous alcoholic solutions. The hydration number are determined from ultrasonic velocity measurements. The surface tension of aqueous alcoholic solutions is measured by the Wilhelmy method. The derivative of predicted surface tension of lithium bromide solution with respect to the additive concentration is almost the same as that of literature data.

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Freezing point depression of selected food solutions were measured at various concentrations in order to reveal the characteristics of solid-liquid phase equilibrium. The measurement were carried out on a hand made apparatus that was calibrated before the measurement by some of selected reagents (acid and sugar) with known thermal properties.
The results revealed that the freezing point depression of selected food solutions deviated from the behavior of the ideal solution with increasing solute concentration, so the water activity for non-ideal solution were introduced to the freezing point depression equation. Further, assuming that the heat of fusion was a equation of temperature, thus the following new equation was led,
ln {(1-X_s)/(l-X_s+α·X_s + β·X_s²)} = A(1/T_o - 1/T_f) - Bln(T_o/T_f)
The goodness of fit of the equation showed the best results.
Futhermore, by using the parameters a formula of freezing ratio and the relative water activities, which showed deviation from the ideal solution, were derived.

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The melting characteristics of liquid ice in a rectangular cavity were studied experimentally. The liquid ice, a mixture of ice particles and ethylene-glycol aqueous solution, was heated by the bottom wall of the cavity. The melting behavior and melting rate of the liquid ice as well as mean heat-transfer coefficient at the heated bottom wall were observed and measured under a variety of conditions of heat flux and initial concentration of the agueous binary solution. It was found that the formation and growth of double-diffusive layers owing to the thermal and solutal buoyancy forces have a great influence on the melting process of the liquid ice.

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Prevention of post-transfusion hepatitis is still a problem in cardiovascular surgery.
We initiated the cryopreservation of autologous blood for the transfusion in elective cardiovascular surgery since 1981.
This study includes 152 surgical cases in which autologous frozen, allogeneic frozen, and/or allogeneic non-frozen blood were used.
In the 152 surgical cases, there were 69 cases in which autologous blood only (Group I) was used; 12 cases with autologous and allogeneic frozen blood (Group II); 46 cases with autologous and allgeneic frozen plus allogeneic non-frozen blood (Group III); and 25 cases with allogeneic frozen plus allogeneic non-frozen blood (Group IV).
No hepatitis developed in Groups I (0%) and II (0%), but there was positive hepatitis in Groups III (4.3%) and IV (8.0%) .
In 357 cases of those who underwent surgery with allogeneic non-frozen whole blood during the same period, the incidence rate of hepatitis was 13.7% (49/357).
Patients awaiting elective surgery can store their own blood in the frozen state.
Patients who undergo surgery with the cryoautotransfusion will not produce any infections or immunologic reactions as opposed to those who undergo surgery with the allogeneic non-frozen blood.

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An experimental study of the performance of a vapour compression heat pump system using a HCFC22 and CFC114 mixture of 20, 40, 60 and 100 mass% of HCFC22 as a working fluid was carried out. Heat Transfer characteristics of the condenser and the evaporator were also investigated. The condenser and the evaporator were counter flow heat exchangers with a smooth copper tube of 12 mmID and 8 m length. The experiments were performed under the conditions that the flow rates of the heat source and sink water and their inlet temperatures of the heat exchangers were kept constant, maintaining the constant evaporating temperature at the inlet of the evaporater. The results indicate that the coefficients of performance (COP) in case of the mixtures are about 45% higher than that of pure HCFC22 in the range of CFC1l4 mass fraction from 0.6 to 0.8 and the effect of the composition of mixtures on COP is well agreement with that obtained from the thermodynamic cycle analysis. Overall heat transfer coefficient of mixtures decreases with increasing CFC114 mass fraction of the mixture and the empirical correlation for the effect of the composion of the mixture on condensation heat transfer is obtained.

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In order to minimize the tolerance between theoretical analysis and actual data, we conducted the test with many kinds of prototypes to obtain actual performance data. We made 19 different kinds, varying H and D, of rolling piston type rotary compressors with identical piston displacement and obtained actual EER. Cylinder height H and bore D are thought to be dominant factors for determining the rotary compressor performance. We, therefore, conducted the test varying H and D, and adjusted the test data, using multiple regulation analysis to investigate what really determines the performance. The result showed that the smaller the product of H and D the higher the efficiency. If the product of H and D is constant, large D results in a small increase of eccentricity and the reliability increases. And we defined some efficiencies and the tendencies of performance clealy.

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Two-cylinder rotary compressor is dynamically balanced well because two rollers in each cylinder chamber are located in opposite sides. Thus, it helps to reduce the circumferential vibration based on the tracking torque ripple for gas compression. This concept has been recently applied to room airconditioners (RACs) for the purpose of reducing vibration and noise of the unit. However, it consequently requires the compressor, which is one of the main noise factors, extremely low noise to reduce RAC noise.
This paper describes generating mechanisms of the compressor noise established by analysis using signal processing and computer aided engineering. In addition, concrete countermeasures are presented for the noise reduction of the two-cylinder rotary compressor. In conclusion, Countermeasures for resonance in cavities were achieved by reducing 630Hz∼1KHz levels and the effect of muffler in the chamber contributed to the reduction of 3KHz∼6KHz levels.

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This paper presents a practical method of calculating hermetic scroll compressor performance, considering mechanical fiction losses leakage loss and heat exchange in the compressor shell. Mechanical friction losses due to fluid resistance of moving parts in the compressor, such as the balancing weight and the orbiting scroll, are considered and estimated. Heat exchange of the refrigerant gas between compressor components is calculated using a simplified thermal analysis model.
The results of these calculations are compared with some measured data. The calculated adiabatic efficiencies agree with the measured values within 3% error, and the calculated discharge gas temperatures agree with the measured va1ues within 3K error, in the revolutionary range from 20 Hz to 150 Hz.

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In replacing CFC-12 with HFC-134a for refrigerator compressors, the compatibility with lubricating oil, and lubrication in general, are of major concern. HFC-134a dose not have adequate solubility with current lubricating oils because of its molecular structure. Current oils also do not provide enough lubricating action when using HFC-134a. A new oil and new materials have to be utilized in order to use HFC-134a.
Developing a new lubricating oil involved numerous tests of different combinations of many polyolester synthetic oils and additives. One of the pre-evaluated methods was pursued via sealed tube tests. Lubricated parts were selected by studies involving a plane-on-roller type of wear test machine and by analyzing the traces of acid material commonly created during the lubricating action.
The matrices of new lubricating oils and new lubricated materials were estimated based on durability tests conducted on compressors and refrigerators. Results showed that polyolester synthetic oils having a low total acid value and including certain quantities of additives did not break down into a tar-like substance and they did not produce composite particles in the operating compressors and refrigerators. The study also found that ceramics and anti-corrosion alloy steel possessed good adrasion-reducing qualities.
Based on our evaluation, we will implement compressor reliability tests and apply HFC-134a to rotary compressors for refrigerators.

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We conducted numerical and experimental analysis to improve the efficiency of dual-cylinder rolling piston type rotary compressors by varying cylinder height H, diameter D and eccentricity E by developing a simulator for obtaining the optimum combination of the cylinder dimensions. As a result, the lower ratio of cylinder height to diameter tends toward higher efficiency. The experimental results correspond to the numerical analysis.
This investigation includes the reduction of superheat loss during the suction process of a compressor with a thermally isolated cylinder and the acquirement of optimum design conditions for an eccentric bearing. The numerical and experimental results show that a thermally isolated cylinder and an eccentric bearing with optimum design are effective for high efficiency.
The results show that the total efficiency of a 3/4 ton prototype dual-cylinder rotary compressor with these effective improvements is higher than that of a conventional single-cylinder type with equivalent capacity.

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Recently, low noise for a compressor is as important as its mechanical efficiency. But it is difficult to accomplish low noise with other demands such as low cost, high speed, light weight, small size and high power. Therefore, it is necessary to take noise into account from the beginning of the design stage.
We have been developing the prediction procedure for a scroll compressor. It consists of the following three stages;
(1) Calculation of the excitation forces by the dynamic behaviro analysis of the rotating elements
(2) Determination of the frequency response of the structures
(3) Prediction of the radiated noise
There are many papers which describe the kinematic model of a scroll compressor but they do not refer to the noise radiation.
This paper describes the features of the procedure from the calculation of excitation forces with the dynamic behavior model of a scroll compressor to the prediction of the radiated noise. The application of the procedure to a middle cooling capacity scroll compressor is also discussed.

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