I nterfaces are what separate one material from another. We sense the world through interfaces, whether touching the surface of a table or seeing the light reflecting off the edge of a glass. Many other interfaces are less visible but still have a place in our lives. Modern solar cells consist of thin layers where interfaces play an important role for charge separation. Catalytic reactions for ...

An essential step in many chemical reactions occurring at gas-solid interfaces is the associative desorption reaction, A(ad) + B(ad) AB(g), where two atoms adsorbed on the surface combine to form a molecule that desorbs to the gas phase. This reaction has been studied in several laboratories1 by a variety of techniques because of its importance to heterogeneous catalysis, high-temperature oxida...

Molecules and atoms can be isolated in low temperature solids, and this offers an opportunity to study their properties in monomeric and complexed forms, and in photochemical reactions. Hydrogen peroxide is an important molecule in various oxidation reactions in industrial chemistry and in the atmosphere. In this thesis, the vibrational properties, structure, and photochemistry of hydrogen pero...

Metallurgical processes are characterized by a complex interplay of heat and mass transfer, momentum reaction kinetics, these interactions play crucial role in reactor performance. Integrating chemistry transport results stiff non-linear equations longer time length scales, which ultimately leads to high computational expense. The current study employs the OpenFOAM solver based on fictitious do...

This dissertation presents the effects of atmosphere, time, and energy input (thermal and mechanical) on the kinetics of gas-solid and solid-solid reactions in systems of dysprosium, uranium, oxygen, and nitrogen. Accordingly, Chapter Two presents a novel synthesis technique used to form DyN via a gas-solid reaction between dysprosium and nitrogen. DyN was rapidly formed through a mechanochemic...

The heats of adsorption on weakly activated ^-aluminium oxide for a number of linear alkanes (from n-butane to n-nonane) and for 2.2.4-trimethylpentane have been determined by GSC and extrapolated to zero surface coverage. The dependance of the adsorption energy on the number of carbon atoms is discussed on the basis of the bidimensional gas model: it is shown that the interactions of the adsor...

A study of the possibilities of pyrolysis for recovering wastes of the rope’s industry has been carried out. The pyrolysis of this lignocellulosic residue started at 250 oC, with the main region of decomposition occurring at temperatures between 300 and 350 oC. As the reaction temperature increased, the yields of pyrolyzed gas and oil increased, yielding 22 wt.% of a carbonaceous residue, 50 wt...

A mathematical model was developed of the drying, volatilization, and combustion phenomena on the packed bed of solid wastes on a moving grate. Gasesolid flow and the heterogeneous chemical reactions were considered. Since experimental work in this area of study is very difficult and costly, the development of such a model is very important. The gas phase turbulence was modeled using keε turbul...