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تسجيل مستخدم جديدSpecific heat of apple at different moisture contents and temperatures
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This work discusses results of experimental investigations of the specific heat, $C$, of apple in a wide interval of moisture contents ($W=0-0.9$) and temperatures ($T = 283-363$ K). The obtained data reveal the important role of the bound water in determination of $C(W,T)$ behaviour. The additive model for description of $C(W)$ dependence in the moisture range of $0.1<W<1.0$ was applied, where the apple was considered as a mixture of water and hydrated apple material (water plasticised apple) with specific heat $C_h$. The difference between $C_h$ and specific heat of dry apple, $Delta Cb=C_h-C_d$, was proposed as a measure of the excess contribution of bound water to the specific heat. The estimated amounts of bound water $W_b$ were comparable with the monolayer moisture content in apple. The analytical equation was proposed for approximation of $C(W,T)$ dependencies in the studied intervals of moisture content and temperature.
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