Thermal Conductivity热导率
*Most from Young, Hugh D., University Physics, 7th Ed. Table 15-5. Values for diamond and silica aerogel from CRC Handbook of Chemistry and Physics. *大多数内容来自Young, Hugh D.，《大学物理》第七版，表15-5。钻石和硅气凝胶的值来自《化学与物理手册》。
Note that 1 (cal/sec)/(cm2 C/cm) = 419 W/m K. With this in mind, the two columns above are not always consistent. All values are from published tables, but can't be taken as authoritative. 注意，1 (cal/sec)/(cm² C/cm) = 419 W/m K。有了这个认识，上面的两列数据并不总是保持一致。所有数值均来自已发表的表格，但不能视为权威。
The value of 0.02 W/mK for polyurethane can be taken as a nominal figure which establishes polyurethane foam as one of the best insulators. NIST published a numerical approximation routine for calculating the thermal conductivity of polyurethane at http://cryogenics.nist.gov/NewFiles/Polyurethane.html . Their calculation for freon filled polyurethane of density 1.99 lb/ft3 at 20°C gives a thermal conductivity of 0.022 W/mK. The calculation for CO2 filled polyurethane of density 2.00 lb/ft3 gives 0.035 W/mK . 聚氨酯的0.02 W/mK可视为一个名义值，这使得聚氨酯泡沫成为一种优秀的绝热材料。NIST在http://cryogenics.nist.gov/NewFiles/Polyurethane.html发布了计算聚氨酯热导率的数值近似程序。他们计算出在20°C时，填充Freon的聚氨酯（密度1.99 lb/ft³）的热导率为0.022 W/mK，而填充CO₂的聚氨酯（密度2.00 lb/ft³）的热导率为0.035 W/mK。
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Index Tables Reference Young Ch 15. 索引表 参考 Young 第15章。 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Wiedemann-Franz Ratio魏德曼-弗兰茨比值
The ratio between thermal and electrical conductivities of metals can be expressed in terms of the ratio: 金属的热导率与电导率的比值可以表示为：
 which may be called the Wiedemann-Franz Ratio or the Lorenz constant. 这可能被称为魏德曼-弗兰兹比值或洛伦兹常数。
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Index Tables Reference Blatt Section 13.2 索引表 参考 Blatt 第13章第2节 | |||||||||||||||||||||||
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