Test methods of thermal diffusivity , specific heat capacity , and thermal conductivity for fine ceramics by laser flash method 激光闪烁法测定精细陶瓷的热扩散率比热容量热传导率试验方法
To measure the thin film ' s diffusivity a testing system based on the ac * calorimetric method is set up , in which a laser source is used to heat up the samples 根据交流量热法原理，构建了一个测量薄膜热扩散率的测试系统。在该系统中，用超短脉宽的激光作为热源。
The heat transfer and thermophysical properties of thin films , including thermal conductivity and thermal diffusivity , differ from the corresponding bulk material when it comes into microscale regime 进入微尺度以后，薄膜材料的导热规律以及热物性(包括热扩散率、热导率)与体材料相比发生了很大的变化，出现了超常现象。
Taking into consideration of the factor include heat diffuse coefficient of soil and time , which affect soil temperature of differential deep , the model can calculates temperature of any time in different depth 模型中充分考虑了土壤热扩散率、时间对温室土壤不同深度的温度影响，可计算出任一时间、土壤不同深度的温度。
The results show that the thermal diffusivity of thin film is smaller than its corresponding bulk material , and with the decreasing of the thickness , the thermal diffusivity also decreasing )的二氧化硅薄膜、氮化硅薄膜、多晶硅薄膜的热扩散率，实验结果表明，薄膜的热扩散率比其体材料的要小，并且随着薄膜厚度的减小，热扩散率也减小。
It presents a mathematical heat transfer model of air and soil temperature in greenhouse basing on the theory of transmission of heat . the model calculates the heat diffuse coefficient of soil by difference method and establishes regression equation on experimental data by sas 基于传热学的热传导方程，利用测试的地温数据，选用差分法计算了土壤热扩散率，应用sas软件拟合了非线性方程，建立了日光温室土壤温度场的数学模型。
