Wetting and spreading in high temperature reactive metal-metal systems is of significant importance in many joining processes. An overview of reactive wetting is presented outlining the principal differences between inert and reactive wetting. New experimental evidence is presented that identifies an early time regime in reactive wetting in which spreading occurs without macroscopic morphological change of the solid-liquid interface. This regime precedes the heavily studied reactive wetting regime. Additional new experimental evidence is presented of kinetic roughening in a high temperature reactive system. Quantitative characterization of this roughening reveals similarities with room temperature systems. These new data provide evidence that supports the existence of several sequential time regimes in the reactive wetting process in which different physicochemical phenomena are dominant.

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Heat conduction in anisotropic materials is quite different from that in isotropic materials. Heat flux vector is commonly not perpendicular to the isothermal surface in anisotropic materials. The advantage and disadvantage of anisotropic materials were analyzed in this paper. The thermal conductivities at one point are not equal in all directions for anisotropic materials. The technique of double skin facade has been successfully applied in many building designs. The application of combining building envelope of anisotropic materials and double skin facade was proposed to avoid its disadvantage. Basing on the combination of anisotropic materials and double skin facade in building envelope, the indoor cooling and heating load decrease in summer and winter respectively. Especially in summer, the effect of energy saving is obvious since the partial magnitude of conductive heat in the envelope made of anisotropic materials could be brought out from the cavity of double skin facade by natural or forced ventilation through it.

Calculation of refrigerant quantities in the heat-exchangers of an air-conditioner on refrigeration and heating operating conditions shows that refrigerant charge quantity in heating operating condition is less than that in refrigeration operating condition. The refrigerant control strategies are most important for refrigeration and heat-pump system. Based on the difference of charged refrigerant quantities of the air-conditioning system between refrigeration and heating operating conditions, the exhaust bypass method was presented in order to improve its operation efficiency. This heat-pump system for controlling refrigerant mass flux was analyzed in detail. The results show that the exhaust bypass method has its advantages in controlling refrigerant mass flux for heat-pump system.