an extensive study of fischer-tropsch synthesis (fts) on alumina-supported cobalt catalysts with different amounts of cobalt is reported. up to 40 wt % of cobalt, is added to the catalysts by impregnation method. the effect of the cobalt loading on the reducibility of the cobalt oxide species, dispersion of the cobalt, average clusters size, water-gas shift (wgs) activity and activity and selec...

We present the activities and selectivities of Pt/Al2O3-based catalysts in the production of hydrogen from methanol through catalytic decomposition. For the decomposition reaction, the Pt and Pd catalysts promoted by ceria exhibit similar activity reaching 100% conversion at 315 C. Promoting with ceria had a positive effect on activity and selectivity. Among all catalysts, the 9% Pt– 10% CeO2/A...

The synthesis of chlorins was performed by hydrogenation porphyrins using diimide generated and consumed under mechanical activation. reaction conditions achievable ball milling, absence solvent use hydrazine hydrate as source, allowed the with high conversion, selectivity, nearly ideal sustainability scores (atom economy 97% E-factor 0.96).

Co-precipitated Cu-MgO catalysts were prepared and evaluated for the gas-phase hydrogenation of furfural. The effect of heating rate at the calcination step was studied by comparing the performance of three catalysts prepared via the same procedure but calcined at different heating rates. The results established that altering the heating rate could influence the structural properties of the cat...

a series of hydroxysemicarbazone derivatives of substituted diaryl ketones and acetophenones were synthesized and their structures were confirmed by analytical and spectroscopic methods including elemental analysis, infrared and nuclear magnetic resonance spectroscopy. the derivatives were prepared by a condensation reaction between n-hydroxysemicarbazide and substituted diaryl ketones or aceto...

As a result of decades of research and industrial development, modern query optimizers are complex software artifacts. However, the quality of the query plan chosen by an optimizer is largely determined by the quality of the underlying statistical summaries. Small selectivity estimation errors, propagated exponentially, can lead to severely sub-optimal plans. Modern optimizers typically maintai...