The fretting wear behavior of plasma spraying CoCrW and Cr3C2-NiCr coatings were investigated. The results showed both plasma spraying coatings were inferior to K417 nickel superalloy in the fretting wear resistance. ...The fretting wear behavior of plasma spraying CoCrW and Cr3C2-NiCr coatings were investigated. The results showed both plasma spraying coatings were inferior to K417 nickel superalloy in the fretting wear resistance. The characterized fatigue delamination of the plasma sprayed coatings was evidently different from that of the homogeneous materials. The lamellar cohesion, oxide inclusions and porosity were critical factors that controlled the fretting wear resistance. In the view of contact mechanics, the fretting wear behavior of plasma spraying coatings was characterized.展开更多
In this study, 7 stains of Rhodopseudomonas sp. were selected from 36 photosynthetic bacteria stains storied in our laboratory. Rhodopseudomonas sp. strain 99 28 has the highest 5 aminolevulinic acid(ALA) production a...In this study, 7 stains of Rhodopseudomonas sp. were selected from 36 photosynthetic bacteria stains storied in our laboratory. Rhodopseudomonas sp. strain 99 28 has the highest 5 aminolevulinic acid(ALA) production ability in these 7 strains. Rhodopseudomonas sp. 99 28 strain was mutated using ultraviolet radiation and a mutant strain L 1, which ALA production is higher than wild strain 99 28 about one times, was obtained. The elements affecting ALA formation of strain 99 28 and L 1 were studied. Under the optimal condition(pH 7 5, supplement of ALA dehydratase(ALAD) inhibitor, levulinic acid(LA) and precursors of ALA synthesis, glycine and succinat, 3000 lx of light density), ALA formation of mutant L 1 was up to 22 15 mg/L. Strain L 1 was used to treat wastewater to remove COD Cr and produce ALA. ALA production was 2 819 mg/L, 1 531 mg/L, 2 166 mg/L, and 2 424 mg/L in monosodium glutamate wastewater(MGW), succotash wastewater(SW), brewage wastewater(BW), and citric acid wastewater(CAW) respectively. More than 90% of COD Cr was removed in four kinds of wastewater. When LA, glycin and succinate were supplied, ALA production was dramatically increased, however, COD Cr could hardly be removed.展开更多
Heat treatment on the laser powder synthesized Ni20A130Fe intermetallic alloy was conducted. The microstructure and composition were analyzed by scanning electron microscopy. The results showed that heat treatment cou...Heat treatment on the laser powder synthesized Ni20A130Fe intermetallic alloy was conducted. The microstructure and composition were analyzed by scanning electron microscopy. The results showed that heat treatment could promote the precipitation of the ductile phase and the coalescence and growth of the sub-crystal grains. These were desirable to improve the ambient ductility and the elevated-temperature strength of the Ni20A130Feintermetallic alloy.展开更多
文摘The fretting wear behavior of plasma spraying CoCrW and Cr3C2-NiCr coatings were investigated. The results showed both plasma spraying coatings were inferior to K417 nickel superalloy in the fretting wear resistance. The characterized fatigue delamination of the plasma sprayed coatings was evidently different from that of the homogeneous materials. The lamellar cohesion, oxide inclusions and porosity were critical factors that controlled the fretting wear resistance. In the view of contact mechanics, the fretting wear behavior of plasma spraying coatings was characterized.
文摘In this study, 7 stains of Rhodopseudomonas sp. were selected from 36 photosynthetic bacteria stains storied in our laboratory. Rhodopseudomonas sp. strain 99 28 has the highest 5 aminolevulinic acid(ALA) production ability in these 7 strains. Rhodopseudomonas sp. 99 28 strain was mutated using ultraviolet radiation and a mutant strain L 1, which ALA production is higher than wild strain 99 28 about one times, was obtained. The elements affecting ALA formation of strain 99 28 and L 1 were studied. Under the optimal condition(pH 7 5, supplement of ALA dehydratase(ALAD) inhibitor, levulinic acid(LA) and precursors of ALA synthesis, glycine and succinat, 3000 lx of light density), ALA formation of mutant L 1 was up to 22 15 mg/L. Strain L 1 was used to treat wastewater to remove COD Cr and produce ALA. ALA production was 2 819 mg/L, 1 531 mg/L, 2 166 mg/L, and 2 424 mg/L in monosodium glutamate wastewater(MGW), succotash wastewater(SW), brewage wastewater(BW), and citric acid wastewater(CAW) respectively. More than 90% of COD Cr was removed in four kinds of wastewater. When LA, glycin and succinate were supplied, ALA production was dramatically increased, however, COD Cr could hardly be removed.
基金granted by the National Postdoctoral Science Foundation of ChinaResearch Foundation of Key Laboratory of High Energy Density Beam Processing Technology of China
文摘Heat treatment on the laser powder synthesized Ni20A130Fe intermetallic alloy was conducted. The microstructure and composition were analyzed by scanning electron microscopy. The results showed that heat treatment could promote the precipitation of the ductile phase and the coalescence and growth of the sub-crystal grains. These were desirable to improve the ambient ductility and the elevated-temperature strength of the Ni20A130Feintermetallic alloy.
