Particle heating/cooling models

The reaction heat probably involves both the gas and particle phases since the reactions were assumed to take place at the inter-faces between the gas and particles thus both the gas and particle molecules reacting are being heated/cooled. However, in some previous studies [18, 97], both the SMR and CO2 reaction heat sources were placed in the particle phase equations. In the study by Chao [21], on the other hand, it was assumed that the SMR reactions occur in the gas phase, whereas the adsorption reaction occurs in the sorbent phase. With these considerations, the reaction heat source term due to the SMR process within the gas thermal temperature transport equation (4.409) was modeled as ... 

This applies, however, only within limits. Many solids are somewhat mobile and can flow very slowly. In that case methods and models of capillarity can be applied. One case where capillarity plays an important role is sintering. In sintering a powder is heated. At a temperature of roughly 2/3 of the melting point of the material the surface molecules become mobile and can diffuse laterally. Thereby the contact areas of neighbouring particles melt and menisci are formed. When cooling, the material solidifies in this new shape and forms a continuous solid. 

Preparation of DMS0-Soluble Starch-g-PAN Samples and Water-Soluble Starch-g-Polyacrylamide. Five grams of starch- -PAN (prepared by either ceric- or cobalt-60 initiation) was dispersed in 333 g of DMSO, and the dispersion was heated for 2 hr at 115°C. The cooled dispersion was then treated with ultrasound for 10 min to mechanically rupture gel particles and to render the polymer soluble (Branson Sonifier, Model S 125 ... 

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