The oxidation behaviour of 10%, 30%, and 50% cold rolled and unprocessed 9Cr 1Mo ferritic steels in air have been studied under isothermal conditions at a temperature of 900°C in a cyclic manner. Oxidation kineti...The oxidation behaviour of 10%, 30%, and 50% cold rolled and unprocessed 9Cr 1Mo ferritic steels in air have been studied under isothermal conditions at a temperature of 900°C in a cyclic manner. Oxidation kinetics was established for all samples on which experiment was conducted in air at 900°C under cyclic conditions for 50 cycles by thermogravimetric technique. Each cycle consisted of 1 hour heating at 900°C followed by 20 min of cooling in air. 10% cold rolled sample followed parabolic rate of oxidation while 30% cold rolled sample showed accelerated rate of weight gain. X-ray diffraction (XRD) and scanning electron microscopy/energy dispersive X-ray (SEM/EDAX) techniques were used to characterise the oxidized sample and their scales. 10% cold rolled steel was found to be more corrosion resistance than other in air oxidation for 50 cycles.展开更多
Yttria-Stabilised Zirconia (YSZ) coatings were deposited on a T-22 boiler steel. NiCrAlY was used as bond coat and YSZ as top coat. Hot corrosion studies were conducted on uncoated as well as plasma spray coated speci...Yttria-Stabilised Zirconia (YSZ) coatings were deposited on a T-22 boiler steel. NiCrAlY was used as bond coat and YSZ as top coat. Hot corrosion studies were conducted on uncoated as well as plasma spray coated specimens in air as well as salt (75 wt.% Na2SO4 + 25 wt.% NaCl) at 900°C under cyclic conditions. The thermogravimetric technique was used to establish kinetics of corrosion. X-ray diffraction (XRD) and scanning electron microscopy/energy-dispersive x-ray analysis (SEM/EDAX) techniques were used to analyse the corrosion products. This YSZ overlay coatings enhance resistance to corrosion significantly which can be attributed to formation of zirconium oxides (ZrO2) and yttrium oxide (Y2O3). This coating was more effective in salt environment and there is an extra phase of ZrS.展开更多
Yttria-Stabilised Zirconia (YSZ) coatings were deposited on a T-91 boiler steel. NiCrAlY was used as bond coat and YSZ as top coat. Hot corrosion studies were conducted on uncoated as well as plasma spray coated speci...Yttria-Stabilised Zirconia (YSZ) coatings were deposited on a T-91 boiler steel. NiCrAlY was used as bond coat and YSZ as top coat. Hot corrosion studies were conducted on uncoated as well as plasma spray coated specimens in air as well as salt (75wt. % Na2SO4 + 25wt. % NaCl) at 900°C under cyclic conditions. The thermogravimetric technique was used to establish kinetics of corrosion. X-ray diffraction (XRD) and scanning electron microscopy/energy-dispersive x-ray analysis (SEM/EDAX) techniques were used to analyse the corrosion products. This YSZ overlay coatings enhance resistance to corrosion significantly which can be attributed to formation of zirconium oxides (ZrO2) and yttrium oxide (Y2O3). This coating was more effective in salt environment and there is an extra phase of ZrS.展开更多
"Candidatus Liberibacter solanacearum"(Lso)are phloem-restricted and unculturable Gram-negative bacteria.Presently five haplotypes have been identified worldwide;but only haplotypes A and B are associated wi..."Candidatus Liberibacter solanacearum"(Lso)are phloem-restricted and unculturable Gram-negative bacteria.Presently five haplotypes have been identified worldwide;but only haplotypes A and B are associated with the vector Bactericera cockerelli(Sulc.)in the Americas.Previous studies showed that Lso-infection reduces B.cockerelli reproductive output and that Lso haplotype B is more pathogenic than Lso haplotype A.To understand the interaction of Lso haplotype B and B.cockerelli,the fitness of Lso-free and Lso B-infected insects,and the expression of vitellogenin(5cKg7-like),a gene involved directly in the insect reproduction were analyzed.Statistical differences in the number of eggs oviposited,and the total number of progeny nymphs and adults were found among crosses of insects with or without Lso.Significant differences in sex proportions were found between Lso B-infected and Lso-free crosses:a higher proportion of Fi adult females were obtained from Lso B-infected mothers.A significant reduction of BcVgl-like was observed in crosses performed with Lso B-infected females compared to the Lso-free insects.In female cohorts of different age,a significant reduction of BcVgl-like expression was measured in 7-d-old Lso B-infected females(virgin and mated)compared with 7-d-old Lso-free females(virgin and mated),respectively.The reduction of BcVgl-like transcript was associated with a lower number of developing oocytes observed in female5s reproductive systems.Overall,this study represents the first step to understand the interaction of Lso B with B.cockerelli,highlighting the effect of Lso B infection on egg production,BcVgl-like expression,and oocyte development.展开更多
文摘The oxidation behaviour of 10%, 30%, and 50% cold rolled and unprocessed 9Cr 1Mo ferritic steels in air have been studied under isothermal conditions at a temperature of 900°C in a cyclic manner. Oxidation kinetics was established for all samples on which experiment was conducted in air at 900°C under cyclic conditions for 50 cycles by thermogravimetric technique. Each cycle consisted of 1 hour heating at 900°C followed by 20 min of cooling in air. 10% cold rolled sample followed parabolic rate of oxidation while 30% cold rolled sample showed accelerated rate of weight gain. X-ray diffraction (XRD) and scanning electron microscopy/energy dispersive X-ray (SEM/EDAX) techniques were used to characterise the oxidized sample and their scales. 10% cold rolled steel was found to be more corrosion resistance than other in air oxidation for 50 cycles.
文摘Yttria-Stabilised Zirconia (YSZ) coatings were deposited on a T-22 boiler steel. NiCrAlY was used as bond coat and YSZ as top coat. Hot corrosion studies were conducted on uncoated as well as plasma spray coated specimens in air as well as salt (75 wt.% Na2SO4 + 25 wt.% NaCl) at 900°C under cyclic conditions. The thermogravimetric technique was used to establish kinetics of corrosion. X-ray diffraction (XRD) and scanning electron microscopy/energy-dispersive x-ray analysis (SEM/EDAX) techniques were used to analyse the corrosion products. This YSZ overlay coatings enhance resistance to corrosion significantly which can be attributed to formation of zirconium oxides (ZrO2) and yttrium oxide (Y2O3). This coating was more effective in salt environment and there is an extra phase of ZrS.
文摘Yttria-Stabilised Zirconia (YSZ) coatings were deposited on a T-91 boiler steel. NiCrAlY was used as bond coat and YSZ as top coat. Hot corrosion studies were conducted on uncoated as well as plasma spray coated specimens in air as well as salt (75wt. % Na2SO4 + 25wt. % NaCl) at 900°C under cyclic conditions. The thermogravimetric technique was used to establish kinetics of corrosion. X-ray diffraction (XRD) and scanning electron microscopy/energy-dispersive x-ray analysis (SEM/EDAX) techniques were used to analyse the corrosion products. This YSZ overlay coatings enhance resistance to corrosion significantly which can be attributed to formation of zirconium oxides (ZrO2) and yttrium oxide (Y2O3). This coating was more effective in salt environment and there is an extra phase of ZrS.
基金supported by U.S.Department of Agriculture-National Institute of Food and Agriculture(USDA-NIFA)2012-67013-19431Texas A&M University and Texas A&M AgriLife Research(Controlling Exotic and Invasive Insect-Transmitted Pathogens).Angelica Albuquerque Tomilhero Frias was supported by a scholarship from the PDSE/CAPES-Brazilian Federal Agency for Support and Evaluation of Graduate Education within the Ministry of Education of Brazil(Process:PDSE 88881.131726/2016-01).
文摘"Candidatus Liberibacter solanacearum"(Lso)are phloem-restricted and unculturable Gram-negative bacteria.Presently five haplotypes have been identified worldwide;but only haplotypes A and B are associated with the vector Bactericera cockerelli(Sulc.)in the Americas.Previous studies showed that Lso-infection reduces B.cockerelli reproductive output and that Lso haplotype B is more pathogenic than Lso haplotype A.To understand the interaction of Lso haplotype B and B.cockerelli,the fitness of Lso-free and Lso B-infected insects,and the expression of vitellogenin(5cKg7-like),a gene involved directly in the insect reproduction were analyzed.Statistical differences in the number of eggs oviposited,and the total number of progeny nymphs and adults were found among crosses of insects with or without Lso.Significant differences in sex proportions were found between Lso B-infected and Lso-free crosses:a higher proportion of Fi adult females were obtained from Lso B-infected mothers.A significant reduction of BcVgl-like was observed in crosses performed with Lso B-infected females compared to the Lso-free insects.In female cohorts of different age,a significant reduction of BcVgl-like expression was measured in 7-d-old Lso B-infected females(virgin and mated)compared with 7-d-old Lso-free females(virgin and mated),respectively.The reduction of BcVgl-like transcript was associated with a lower number of developing oocytes observed in female5s reproductive systems.Overall,this study represents the first step to understand the interaction of Lso B with B.cockerelli,highlighting the effect of Lso B infection on egg production,BcVgl-like expression,and oocyte development.