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Abstract: This paper presents thermal conductivity data for 40 foods, enthalpy data for 58 foods and density data for nine foods, along with the compositions of the foods. Measurements cover a range of solid food types (including meats, fats, offal, fish, dairy products and horticultural products). Some measurements reported are for foods that have never before been studied, others have been published elsewhere, but are included here for convenience. Thermal conductivity was measured using a guarded hot-plate apparatus, enthalpy using an adiabatic calorimeter and density using a water displacement meter. Thermal conductivity and enthalpy values were measured within the temperature range of −40°C to +40°C. [Copyright &y& Elsevier]

Abstract: Due to the concern for the effects of the release of HFC refrigerants on the global environment caused by the high global warming potential of these substances, there is a large interest in Europe and elsewhere for the use of hydrocarbons as refrigerants. This article presents a comparison of the properties and performance of hydrocarbons as refrigerants in small-size heat pump and refrigeration systems (<20kW cooling). A listing of several commercially available systems is also presented. The designs, safety precautions and performances of some of these systems are described. As a general conclusion, it is shown that using hydrocarbons will result in COPs equal to, or higher than, those of similar HFC systems. It is also shown that components suitable for hydrocarbon systems are available on the market, even though the number of large-size hermetic compressors is limited. A major concern, which should not be taken lightly, is the safety issue. Reduced charge through indirect systems and compact heat exchangers, outdoor placing of the unit, hydrocarbon sensors and alarms and forced ventilation are all steps which may be applied to reduce the risks under normal operation. [Copyright &y& Elsevier]

Abstract: A W/O type emulsion was developed as a new thermal material for ice storage. The water contents of the emulsions were 70, 80 and 90vol%, and silicone oil was used. An amino group modified silicone oil with 0.9vol% was used as a surface-active agent. The freezing points of those emulsions were 0°C. However, due to the emulsion structure, the propagation rate of supercooling dissolution for each emulsion was very slow. Therefore, the propagation rate and maximum supercooling degree were estimated using probability, varying the water content of the emulsion, the method of the ice nucleus charging, and the size and number of ice nuclei. In addition, the influence of various parameters on the propagation rate and maximum supercooling degree was clarified. [Copyright &y& Elsevier]