the no removal over oxide sorbents (k2o/al2o3 , cao/al2o3 and bao/al2o3) at a loading of up to 25 wt.% was investigated using a synthetic diesel exhaust gas containing  1,000 ppm no, 1000 ppm iso-butane (i-c4h10), 8% o2 and n2 balance. the reactor was operated  at 250 oc to 450 oc for the activity study. no was effectively stored (removal efficiencies between 30-60 %) as nitrate under experimen...

welders may suffer from welding fumes generated during the process if the ventilation systems are improperly applied. the objective of the present work was to study the mitigation of air pollutants at welding stations, using different ventilation scenarios. four air pollutants including iron oxide, respirable dust, ozone, and carbon monoxide were measured during four different ventilation scena...

We found that two lithium niobate-type oxides, CdPbO3 and PbNiO3 were synthesized by high-pressure as metastable low-pressure perovskite-type phases. We then discussed the stability of lithium niobate-type and perovskite-type oxides relative to oxides with other structure for ABO3 compounds. Consequently, the tolerance factor of perovskite is not the only predominant one to determine the stabil...

Here, for the first time, it is reported that some Mn oxides after a few hours convert to a nanolayered Mn oxide when the compounds are used as water-oxidizing catalysts in a water electrolysis device at near neutral pH and in the presence of LiClO4. The new nanolayered Mn oxide is more active than other Mn oxides toward water oxidation. This result is very important for artificial photosynthet...

Manganese (Mn) oxides are among the most reactive sorbents and oxidants within the environment, where they play a central role in the cycling of nutrients, metals, and carbon. Recent discoveries have identified superoxide ([Formula: see text]) both of biogenic and abiogenic origin as an effective oxidant of Mn(II) leading to the formation of Mn oxides. Here we examined the conditions under whic...

Sulfur oxides are produced from the burning of fossil fuels, mainly coal and oil, and the smelting of metal ores that contain sulfur. Emissions of sulfur oxides cause serious impacts on human health and the environment, both directly and as a result of the way they react with other substances in the air. Sulfur oxides are main precursors of atmospheric acidification, aerosol generation, and aci...

Transition metal oxides are considered as prototype models of reactions involving oxidative processes [1]. In this way, the detailed understanding of their electronic and molecular structure is of great interest in the prediction of their catalytic behavior and chemical reactivity toward inert organic molecules which are of industrial interest. In particular, it is possible to highlight the sel...

It is well-documented that certain oxides (such as Re2O7, B2O3, MoO3, V2O5, etc.) can provide friction coefficients of 0.1-0.3 to sliding surfaces at elevated temperatures and thus they are often referred to as lubricious oxides in the tribology literature. In a recently proposed crystal chemical model, Erdemir was able to establish a close correlation between the reported friction coefficients...

BACKGROUND Organic dye pollution in water has become a major source of environmental pollution. Mn(III/IV) oxides have attracted a great deal of attention to remove organic dye pollutants due to their unique structures and physicochemical properties. Numerous studies have reported the removal of dye by various Mn(III/IV) oxides through catalytic degradation and adsorption. The crystalline struc...

Lead sorption efficiencies (sorption per surface area) were measured for a number of natural and synthetic Mn and Fe-oxides using a flow through reactor. The Mn-oxide phases examined included synthetic birnessite, natural and synthetic cryptomelane, and natural and synthetic pyrolusite; the Fe-oxides studied were synthetic akaganeite, synthetic ferrihydrite, natural and synthetic goethite, and ...