Two different possible mechanisms of water gas shift reaction including formate and redox mechanisms on the Ag5 cluster were investigated using DFT computations. All the elementary steps involved in both mechanisms were considered. It was observed that dissociation of H2Oads and OHads, as well as formation of CO2(ads), required activation e...

The effect of mechanical activation on structural changes and kinetics of carbothermic reduction of hematite with graphite was studied in this research. Hematite powder mixture with graphite (with stoichiometry ratio C/O=1) was milled for the time periods of zero to 50 hours, and the structural changes were studied using X ray diffraction (XRD). The effect of mechanical activation on the kineti...

Isothermal redox kinetics of as-received Co3O4 (AC), 1 h ball milled Co3O4 (BC), and 1 h ball milled Co3O4-15wt.% Fe2O3 (BCF) was investigated at various temperatures (1130, 1100, 1070, and 1040 °C for reduction and 830, 860, and 890°C for re-oxidation) by thermogravimetric method. It was found that mechanic...

A series of 8 new complexes of titanium and zirconium with diamido ligands bearing an ethylene and propylene bridge between the two amido groups were synthesized and tested for ethylene polymerization. Titanium complexes bearing an ethylene bridge between the two amido groups showed higher activities than the derivatives with a propylene bridge. In the case of the zirconium complexes, the p...

Spherical pellets of antimony sulphide were dissolved in 1 molar sodium hydroxide solutions at different temperatures. It was found that the shrinking core with ash layer model could satisfactorily explain the dissolution process. Using this model it was found that initially the rate controlling step is a chemical reaction with activation energy of 10.2 kJ/mol. As the ash layer builds up, diffu...

In this research, a mineral barite powder was reduced by carbon monoxide gas and the effects of reduction time and temperature was investigated as well as barite particle size. Results showed that the best result would be feasible when the barite particle sizes are between (-70 +100) in mesh scale. The barite reduction could reach the maximum level (98%) after reduction by carbon monoxide at 85...

The strain rate sensitivity (SRS) of Mg–1.5 wt% Gd processed by conventional extrusion and 2 passes of simple shear extrusion (SSE) was investigated by shear punch testing. Shear punch tests were conducted at initial shear strain rates in the range of 0.003–0.3 s-1 and at temperatures in the range of 573–773 K. A fine-grained microstructure with an average grain size of about 2.5 µm, obtained a...

the thermal degradation of polyethylene (pe) was carried out in the absence and presence ofcatalystes x-zeolite and silica-alumina at different temperatures. the optimum pe/catalysisratio was 0.25:0.05 g/g, which produced highest degradation value. pe and pe/catalysis werecharacterized by thermogravimetric analysis. the thermal degradation properties of polymerhave been studied by infrared spec...

in this research chloroaiminium and copper phthalocyanine(clalpc and cupc)were purified twice, using entrained sublimitation techniques. ohmic contacts were made on the samples using the electrical properties of both (clalpc and cupc) were studied over a range of temperatures. the activation energies of these materials were measured using both forward and reverse current-voltage characteristic ...