The paper contrasts the main drawbacks of silica based packings such as their relative thermal and chemical instability with excellent stability of metal oxides. The paper concerns mainly ZrO2, TiO2 and Al2O3. Surface chemistry of the oxides is however very different from that of silica. Ability of the oxides to ionand ligand-exchange is discussed from a chromatographic point of view.

group viii b metal oxides supported on gamma-alumina were investigated as catalysts and promoters of moo3 hydrodesulfurization catalysis. superior promotion was observed in pbo promoted catalyst compared to that of coo, the typically accepted promoter. other metal oxides, sno and ho2o3 exhibited reasonable hydrodesulfurization catalysis promotion but lower than for coo promoted catalyst.

A direct C-H/P-H functionalization of heteroaryl N-oxides with H-phosphonates is described. A wide variety of heteroaryl phosphonates were obtained in up to 92% yield in a chemo- and regioselective manner, under oxidant and metal free conditions. This procedure features practicality, high efficiency, environmental friendliness and atom economy.

An efficient synthesis of a range of 1,2-benzisoxazoles using an improved 1,3-dipolar cycloaddition of nitrile oxides and benzyne is described. Key to the procedure is the in situ generation of the reactive nitrile oxide and benzyne reaction partners mediated by TBAF. Reactions are complete within 30 s, giving the target products in good to excellent yield.

An efficient protocol for the synthesis of a range of 1,2-benzisoxazoles using an improved 1,3-dipolar cycloaddition of nitrile oxides and benzyne is described. Key to the procedure is the in situ generation of the reactive nitrile oxide and benzyne reactants simultaneously.

Breakdown of thin gate oxides from heavy ions is investigated using capacitor test structures. Soft breakdown was observed for 45 Å oxides, but not for 75 Å oxides. Lower critical fields were observed when experiments were done with high fluences during each successive step. This implies that oxide defects play an important role in breakdown from heavy ions and that breakdown occurs more readil...

Metal oxides play a very important role in many areas of chemistry, physical and materials science. Metal oxides are formed as a consequence of co-ordination tendency of metal ions so that oxide ions form co-ordination sphere around metal ions and give rise to close packed structure. The different physical, magnetic, optical and chemical properties of metal oxides are of great interest to chemi...

Nitrogen Dioxide: Nitrogen dioxide (NO2) is one of a group of highly reactive gasses known as "oxides of nitrogen," or "nitrogen oxides (NOx)." Other nitrogen oxides include nitrous acid and nitric acid. While EPA’s National Ambient Air Quality Standard covers this entire group of NOx, NO2 is the component of greatest interest and the indicator for the larger group of nitrogen oxides. NO2 forms...

background: nitrogen oxides occur in the atmosphere in six forms of namely: n2o , no , no2 , n2o3, n2o4 and n2o5 .among these oxides no2 is the most important air pollutant because of its relatively high toxicity and its ubiquity in ambient air. in this research griess-saltzman method was utilized for determination of nitric oxide and nitrogen dioxide in the atmosphere of different laboratories...

Gold-catalyzed α-furanylations of 8-alkylquinoline N-oxides have been achieved using alkenyldiazo carbonyl species as nucleophiles. The reactions are applicable to a reasonable range of alkenyldiazo species and 8-alkylquinoline N-oxides. The reaction mechanism is postulated to involve an initial nucleophilic addition of diazocarbonyl species at 8-alkylquinoline N-oxides, followed by diazo decom...