C-SiC coatings were prepared on stainless steel substrate by the middle frequency magnetron sputtering （MFMS） and ion beam mixing technique. After deposition, these samples were implanted by 5 keV hydrogen ion beam ...C-SiC coatings were prepared on stainless steel substrate by the middle frequency magnetron sputtering （MFMS） and ion beam mixing technique. After deposition, these samples were implanted by 5 keV hydrogen ion beam at a dose of 1×1018 ion/cm2. Some samples were heat treated at different temperatures from 273 K to 1173 K separately. The surface morphology, surface concentration of the elements of the C-SiC coatings and element iron from substrate as well as their depth profiles were checked with SEM, XPS and SIMS analyses. The results show that the composition of the coatings is changed due to heat treatment at different temperatures. The C-50%SiC coating with an excellent hydrogen resistant property can act as hydrogen barrier at the temperature below 723 K. But the hydrogen resistant property of the coating becomes bad when it is used at the temperature of 1023 K.展开更多
为比较γ射线和电子束对牛血清辐照灭菌后蛋白损伤的差异,将牛血清辐照0~50 k Gy后,测定蛋白浓度、浊度、疏水性以及纯化后白蛋白的二级结构、热稳定性和分子量大小的变化。结果表明,牛血清辐照后蛋白浓度下降,浊度和疏水性上升,电子束...为比较γ射线和电子束对牛血清辐照灭菌后蛋白损伤的差异,将牛血清辐照0~50 k Gy后,测定蛋白浓度、浊度、疏水性以及纯化后白蛋白的二级结构、热稳定性和分子量大小的变化。结果表明,牛血清辐照后蛋白浓度下降,浊度和疏水性上升,电子束辐照的变化幅度低于γ射线。以10 k Gy剂量为转折点,白蛋白的α螺旋含量先升后降,β折叠含量先降后升,变化范围分别为0%~15.2%和40.6%~52.4%。自由卷曲含量始终呈上升趋势。牛血清辐照后白蛋白组分的DSC图出现放热杂峰,出峰时间延长,γ射线辐照的峰温随剂量增加（77.4℃升至79.1℃）而升高,电子束辐照的趋势相反。照后白蛋白在GPC图中出现分布加宽的杂峰。这说明射线和电子束作用使牛血清同时发生交联和降解反应,破坏白蛋白二级结构,牛血清蛋白分子出现疏水基团外露,浊度增加,以及浓度下降的现象。常温辐照时电子束与γ射线效果差异不明显。展开更多
基金Financial support was provided by the NSFC (No.21202136)the Young Teachers Program and the Start-up Foundation of Hubei University of Technology and Science (No.KY13040 and KB1008,respectively)
基金Project(Q20122808)supported by the Department of Education of Hubei Province,ChinaProject(59781002)supported by the National Natural Science Foundation of China
文摘C-SiC coatings were prepared on stainless steel substrate by the middle frequency magnetron sputtering （MFMS） and ion beam mixing technique. After deposition, these samples were implanted by 5 keV hydrogen ion beam at a dose of 1×1018 ion/cm2. Some samples were heat treated at different temperatures from 273 K to 1173 K separately. The surface morphology, surface concentration of the elements of the C-SiC coatings and element iron from substrate as well as their depth profiles were checked with SEM, XPS and SIMS analyses. The results show that the composition of the coatings is changed due to heat treatment at different temperatures. The C-50%SiC coating with an excellent hydrogen resistant property can act as hydrogen barrier at the temperature below 723 K. But the hydrogen resistant property of the coating becomes bad when it is used at the temperature of 1023 K.
文摘为比较γ射线和电子束对牛血清辐照灭菌后蛋白损伤的差异,将牛血清辐照0~50 k Gy后,测定蛋白浓度、浊度、疏水性以及纯化后白蛋白的二级结构、热稳定性和分子量大小的变化。结果表明,牛血清辐照后蛋白浓度下降,浊度和疏水性上升,电子束辐照的变化幅度低于γ射线。以10 k Gy剂量为转折点,白蛋白的α螺旋含量先升后降,β折叠含量先降后升,变化范围分别为0%~15.2%和40.6%~52.4%。自由卷曲含量始终呈上升趋势。牛血清辐照后白蛋白组分的DSC图出现放热杂峰,出峰时间延长,γ射线辐照的峰温随剂量增加（77.4℃升至79.1℃）而升高,电子束辐照的趋势相反。照后白蛋白在GPC图中出现分布加宽的杂峰。这说明射线和电子束作用使牛血清同时发生交联和降解反应,破坏白蛋白二级结构,牛血清蛋白分子出现疏水基团外露,浊度增加,以及浓度下降的现象。常温辐照时电子束与γ射线效果差异不明显。
