Gas-solid interaction

Decomposition following thermal treatment of the separated material yielding solid oxides and gaseous components (solid-gas interaction). 

This equipment could be used for chemical reactions based on a strong solid-gas interaction with gas adsorbed on powder such as limited air oxidation or with gas release (water, ammonia) such as esterification. The oversized applicator structure permits the design of dielectric pipe to manage such matter transfers. This equipment can be also used for many reactions on solid supports. A typical unit is powered with microwave generators units of 2 or 6 kW for a total microwave power close to 20 or 60 kW. 

To illustrate exactly how these mles work, a number of examples follow. In the first, the formation of antisite defects, a simple example that does not involve changes in atom numbers or charges on defects, is described. Secondly, two reactions involving oxides, nickel oxide and cadmium oxide, both of which are nonstoichio-metric, but for opposite reasons, indicate how to deal with a solid-gas interaction... 

The thickness of the layer of the adsorbed molecules is the characteristic distance scale for fractal surface. (3) Van der Waals attraction forces between solid/gas interactions and the liquid/gas surface tension forces are contributed to the grand potential of the system. 

For higher coverage, the interface is controlled by the liquid-gas surface tension forces (capillary condensation) and van der Waals forces between solid/gas interactions are negligible. Then, the relationship between C and dv sl, changes to the following... 

Gas-liquid relationships, in the geochemical sense, should be considered liquid-solid-gas interactions in the subsurface. The subsurface gas phase is composed of a mixture of gases with various properties, usually found in the free pore spaces of the solid phase. Processes involved in the gas-liquid and gas-solid interface interactions are controlled by factors such as vapor pressure-volatilization, adsorption, solubility, pressure, and temperature. The solubility of a pure gas in a closed system containing water reaches an equilibrium concentration at a constant pressure and temperature. A gas-liquid equilibrium may be described by a partition coefficient, relative volatilization and Henry s law. 

Waals forces between solid/gas interactions are negligibly small. Then, the relationship between CSP and tislirrsP changes to the following expression. 

Van der Waals forces between solid/gas interactions and the liquid/gas surface tension forces represent the limiting cases, but in general both the forces competitively affect the adsorption process. Therefore, in determining the surface fractal dimension by using the SP method, it is very important to use appropriate relation between CSP and <4n-r,sp- According to Ismail and Pfeifer,60 the threshold for the dominant forces between van der Waals forces and the liquid/gas surface tension forces is given as... 

Calcium-Bromine-Iron Cycle The calcium-bromine-iron (Ca-Br, or UT-3) cycle involves solid-gas interactions that may facilitate the reagent-product separations, as opposed to the all-fluid interactions in the SI cycle, but it will introduce the problems of solids handling, support, and attrition. This process is formed of the following reactions (Doctor et al., 2002) ... 

Solid-Gas Interactions Between Small Gaseous Molecules and Transition Metals in the Solid State. Toward Sensor Applications... 

In order to try to clarify the different types of mechanism involving either redox cycles and/or acid-base properties, a study of the surface chemistry of single, doped and mixed oxides is of much interest. The calorimetric technique, by allowing heat transfer measurements, can provide very informative data on the thermodynamics of solid-gas interactions and for the study of the surface and reactivity of these metal oxides. 

Hadjoudis, E., Kariv, E. and Schmidt, G. M. J. (1972). Solid-gas interactions. II. Solid-state cis-trans isomerization of alkoxycinnamic acids in iodine vapor. J. Chem. Soc., Perkin Trans. II, 1056-60. [238]... 

Electrical conductivity measurements They were carried out in a static-type cell, designed for powder samples, which allows in situ measurements from the beginning of the pretreatment up to subsequent solid-gas interactions. The results refer only to the support in the case of supported metal catalysts,... 

Garrone E and Otero Arean C (2005), Variahle temperature infrared spectroscopy a convenient tool for studying the thermodynamics of weak solid-gas interactions , Chem Soc Rev, 34, 846. 

In this paper, a mathematical model for coupled coal/rock mass deformations and gas leak flow in parallel coal seams is presented from a new viewpoint of solid-gas interaction. It consists of equations for the gas leak flow, equations for coal/rock mass deformation and the... 

At the early stage of multilayer build-up, the interface is dominandy controlled by van der Waals forces between solid/gas interactions and the liquid/ surface tension forces are neglected. Then, the relationship between Cgp and r4urf,sp is written as... 

Another problem to be discussed is the nonequilibrium state of the powdered polysulfides prepared by solid-gas interactions. In these cases the rate-controlling process is most often the sulfur diffusion in solids. A thick product layer formed on the unreacted starting solid inhibits the sulfur diffusion, resulting in a nonequilibrium state. To describe this state, one can use some indicators which are shared by many sulfide materials (Vaughan and Craig 1978). First, there is a greater number of phases on the surface of the solids than would follow from Gibbs rule the duration of the experiment has a dramatic effect on the number of phases and the compositional identity of the final products. 

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