Specific heat of glass

The specific heat of glasses is of great value in heat engineering calculations. With solids and liquids, use is generally made of specific heat under constant pressure (cp) which corresponds to the change of heat content related to 1 g of substance ... 

D. E. Sharp, L.B. Ginther, "Effect of composition and temperatrue on the specific heat of glass". Journal of the American Cerarrtic Society, 34, 260-271, (1951). 

As the measurements have shown, thermal properties of filled polymers depend considerably on filler orientation. Thermal conductivity and specific heat of glass plastics with formaldehyde and epoxy binder increase with increasing temperature, whereas thermal diffusivity falls in inverse proportion with temperature. The direction of the heat flux and orientation of the filler are responsible for the conductance and thermal diffusion in a given direction. Specific heat does not practically depend on the heat flux direction, since it characterizes the scalar value, i.e., energy accumulation. 

TABLE 5.5 Factor for Calculation of Mean Specific Heat of Glass from the Composition... 

Mercury has a specific heat of 0.140 J/g °C. Assume that a thermometer has 20 (2 significant figures) grams of mercury. How much heat is absorbed by the mercury when the temperature in the thermometer increases from 98.6°F to 103.2°F (Assume no heat loss to the glass of the thermometer.)... 

G. E. Gibson and W. F. Giauque. "The Third Law of Thermodynamics. Evidence from the Specific Heats of Glycerol that the Entropy of a Glass Exceeds that of a Crystal at the Absolute Zero". J. Am. Chem. Soc.. 45. 93-104 (1923). 

By using Lipatov s theory, interrelating the abrupt jumps in the specific heat of composites at their respective glass transition temperatures with the values of the extents of these boundary layers, the thickness of the mesophase was accurately calculated. 

The specific heat of E glass fiber is 0.192 cal/gm K (i.e., 0.804 J/gm K) [73]. The specific heat of caprolactam as a function of temperature was fitted to the following equation from experimental data available in Monsanto ... 

Wnnderlich, B. Study of the change in specific heat of monomeric and polymeric glasses during the transition. J. Phys. Chem. 64, 1052 (1960)... 

Perhaps the best comparison is that of Alford and Dole (1955) who measured the specific heat of a sample of polyvinyl chloride from the same source as the polyvinyl chloride used by Fuoss (1941) in his extensive dielectric loss studies. The comparison between c and e", the dielectric loss factor measured at 60 cps, is shown in Fig. 15, and covers the glass transition range. Note that the peak of the dielectric loss curve is at 100° C, about 20 degrees higher than the inflection point of the c — T curve. 

Alford, S., and M. Dole Specific heat of synthetic high polymers. VI. A study of the glass transition in polyvinyl chloride. T. Am. Chem. Soc. 77, 4774-4777 (1955). 

In DSC the measured energy differential corresponds to the heat content (enthalpy) or the specific heat of the sample. DSC is often used in conjunction with TA to determine if a reaction is endothermic, such as melting, vaporization and sublimation, or exothermic, such as oxidative degradation. It is also used to determine the glass transition temperature of polymers. Liquids and solids can be analyzed by both methods of thermal analysis. The sample size is usually limited to 10-20 mg. 

All parts of the tamarind tree are useful in one way or another. Tamarind is valued mostly for its fruit and pulp, which is used for a wide variety of domestic and industrial purposes (Kulkarni et al., 1993), in particular to prepare juice, jam, syrup and sweets. Tamarind juice concentrate (TJC) is a convenient product due to the ease with which it can be dissolved and reconstituted in warm water. The specific heat of TJC increases with temperature and the glass transition temperature of the product is -70.74°C (Ahmed etah, 2007). Tamarind intake appears to... 

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