Single body, balance laws

In Chap. 1 we postulate the First Law as (1.3) which gives the existence of internal energy fulfilling (1.5). Similarly as in Sect. 2.1 we can write (1.5) as a balance the time derivative of internal energy is equal to the sum of heating and power (cf. (2.1)) [11, 18, 22, 35]. This is applicable to the material volume of a (nonuniform) body or its arbitrary part consisting of a single substance. We postulate the existence of a... 

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