[1] Aqueous-phase oxidation (in clouds and aerosols) is a potentially important source of organic aerosol and could explain the atmospheric presence of oxalic acid. Methylglyoxal, a water-soluble product of isoprene, oxidizes further in the aqueous phase to pyruvic acid. Discrepancies in the literature regarding the aqueous-phase oxidation of pyruvic acid create large uncertainties in the inclo...

Clouds play an important role in the oxidation of sulfur dioxide to sulfate, since aqueous phase sulfur dioxide oxidation is typically much faster than oxidation in the gas phase. Important aqueous phase oxidants include hydrogen peroxide, ozone and oxygen (catalyzed by trace metals). Because quantities of emitted sulfur dioxide in China are so large, however, it is possible that they exceed th...

titanium aluminide and its alloys have been utilized in automotive, aerospace and power industries because of their specific properties such as low density (~ 4 g/cm3), high melting temperature (~ 1460 °c) and excellent high-temperature strength. ti-48al intermetallic compound and its alloys with 1.5, 3 and 5 at.%mn were produced with mechanical alloying of elemental powders for 50 hours. the p...

During thermal oxidation of binary amorphous AlxZr1-x solid solutions over wide alloycomposition (0.26 ≤ x ≤ 0.68) and oxidation-temperature (350 °C – 560 °C) ranges, a single amorphous ternary oxide phase of well-defined stoichiometry, (Al0.33Zr0.67)O1.83, emerges. The composition of this unexpectedly stoichiometric ternary amorphous oxide phase, that develops instead of the crystalline oxide ...

Molybdenum containing catalysts are widely used for the selective oxidation of propene in the presence of gas phase oxygen at temperatures above ~600 K. Crystalline (Mo,V,W)5O14 constitutes a three-dimensional model system for the more complex molybdenum based mixed oxide catalysts that are employed industrially for various partial oxidation reactions [1]. However, little is known about the coo...

This review outlines several approaches for designing new and environmentally friendly heterogeneously catalyzed oxidation processes for the synthesis of fine and intermediate chemicals. Environmentally benign oxidants such as molecular oxygen, hydrogen peroxide or nitrous oxide can be activated on suitable heterogeneous catalysts showing high activity and selectivity toward the desired oxygena...

Under technologically relevant oxygen-rich conditions, the reaction mechanism of CO oxidation over transition metals can be complicated by the formation of oxides. Questions of whether the active surface for CO oxidation is a pristine metal, a surface oxide, or a bulk oxide is still under active debate. In this study, density functional theory calculations are used to model CO oxidation on the ...

The oxidation of biogenic dimethyl sulfide (DMS) emissions is a global source of cloud condensation nuclei. The amounts of the nucleating H2SO4(g) species produced in such process, however, remain uncertain. Hydrophobic DMS is mostly oxidized in the gas phase into H2SO4(g) + DMSO(g) (dimethyl sulfoxide), whereas water-soluble DMSO is oxidized into H2SO4(g) in the gas phase and into SO4(2-) + Me...

[1] The ozonolyses of six monoterpenes (a-pinene, b-pinene, 3-carene, terpinolene, a-terpinene, and myrcene), two sesquiterpenes (a-humulene and b-caryophyllene), and two oxygenated terpenes (methyl chavicol and linalool) were conducted individually in Teflon chambers to examine the gas-phase oxidation product and secondary organic aerosol (SOA) yields from these reactions. Particle size distri...