Magnesium hydride and its compounds have a high hydrogen storage capacity and are inexpensive, and thus have been considered as one of the most promising hydrogen storage materials for on-board applications.

Methamidophos is one of the most widely used organophosphorus insecticides usually detectable in the environment. A facultative methylotroph, Hyphomicrobium sp. MAP-1, capable of high efficiently degrading methamidophos, was isolated from methamidophos-contaminated soil in China. It was found that the addition of methanol significantly promoted the growth of strain MAP-1 and enhanced its degradation of methamidophos. Further, this strain could utilize methamidophos as its sole carbon, nitrogen and phosphorus source for growth and could completely degrade 3,000 mg l(-1) methamidophos in 84 h under optimal conditions (pH 7.0, 30 degrees C). The enzyme responsible for methamidophos degradation was mainly located on the cell inner membrane (90.4%). During methamidophos degradation, three metabolites were detected and identified based on tandem mass spectrometry (MS/MS) and gas chromatography-mass spectrometry (GC-MS) analysis. Using this information, a biochemical degradation pathway of methamidophos by Hyphomicrobium sp. MAP-1 was proposed for the first time. Methamidophos is first cleaved at the P-N bond to form O,S-dimethyl hydrogen thiophosphate and NH(3). Subsequently, O,S-dimethyl hydrogen thiophosphate is hydrolyzed at the P-O bond to release -OCH(3) and form S-methyl dihydrogen thiophosphate. O,S-dimethyl hydrogen thiophosphate can also be hydrolyzed at the P-S bond to release -SCH(3) and form methyl dihydrogen phosphate. Finally, S-methyl dihydrogen thiophosphate and methyl dihydrogen phosphate are likely transformed into phosphoric acid.

a b s t r a c t a r t i c l e i n f o Available online xxxxAnodic coatings with and without superfine Al 2 O 3 particles were prepared on AZ31 magnesium alloy by anodizing in an environmentally friendly alkaline solution. The microstructure and morphology of the coatings were analyzed using X-ray diffraction and scanning electron microscopy equipped with energy dispersive spectroscopy. The corrosion resistance of the uncoated AZ31 substrate and the anodic coatings was evaluated in 3.5% NaCl solution through potentiodynamic polarization tests. Friction and wear tests were performed to evaluate the wear resistance of the samples. The results show that the composite oxide coating has better corrosion resistance than the coating without Al 2 O 3 nanoparticles. The microhardness of the composite coating with reinforced Al 2 O 3 nanoparticles is up to 358 HV. When rubbed at 10 N load for 3 min during sliding against GCr15 at ambient temperature, the wear loss of the film was about 0.04 mm 3 , which is about one-tenth of that of the anodizing coating without nanoparticles. Therefore, the composite anodizing coating with Al 2 O 3 nanoparticles shows better anti-corrosion and anti-wear properties than the coating without Al 2 O 3 nanoparticles.

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