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The specific heat of the human body calculated from the measured values of individual tissues is 2.98 kJ · kg−1 · °C−1. This is 17% lower than the earlier wider used one based on non measured values of 3.47 kJ · kg−1· °C−1.
Effusivity describes the corresponding transient process of heat flow through some local area of interest. In special cases of steady state, the thermal conductivity (k) may be sufficient to describe heat transfers inside solid or rigid bodies by applying Fourier's law. [6] [7] Thermal diffusivity is often measured with the flash method.
Heat flux can be directly measured using a single heat flux sensor located on either surface or embedded within the material. Using this method, knowing the values of k and x of the material are not required. The multi-dimensional case is similar, the heat flux goes "down" and hence the temperature gradient has the negative sign:
The heating value (or energy value or calorific value) of a substance, usually a fuel or food (see food energy), is the amount of heat released during the combustion of a specified amount of it. The calorific value is the total energy released as heat when a substance undergoes complete combustion with oxygen under standard conditions.
Values in parentheses are extrapolated, interpolated, or estimated. *It happens that the online record has the thermal conductivity at 30 Kelvins and ∥ {\displaystyle \parallel } to the c axis posted at 1.36 W⋅cm −1 K −1 and 78.0 Btu hr −1 ft −1 F −1 which is incorrect.
This value for the specific heat capacity of nitrogen is practically constant from below −150 °C to about 300 °C. In that temperature range, the two additional degrees of freedom that correspond to vibrations of the atoms, stretching and compressing the bond, are still "frozen out".
All values refer to 25 °C and to the thermodynamically stable standard state at that temperature unless noted. Values from CRC refer to "100 kPa (1 bar or 0.987 standard atmospheres)". Lange indirectly defines the values to be standard atmosphere of "1 atm (101325 Pa)", although citing the same NBS and JANAF sources among others.
For example, values of the Gibbs energy obtained from high-temperature equilibrium emf methods must be identical to those calculated from calorimetric measurements of the enthalpy and entropy values. The database provider must use recognized data analysis procedures to resolve differences between data obtained by different types of experiments.