硅橡胶复合材料被广泛应用于高压输电外绝缘领域,特别是室温硫化硅橡胶(room temperature vulcanized,RTV),被广泛用作防污闪涂料。目前其检测分析方式以取样后实验室分析为主,尚无可现场检测RTV材料成分及老化状态的技术。该文利用激...硅橡胶复合材料被广泛应用于高压输电外绝缘领域,特别是室温硫化硅橡胶(room temperature vulcanized,RTV),被广泛用作防污闪涂料。目前其检测分析方式以取样后实验室分析为主,尚无可现场检测RTV材料成分及老化状态的技术。该文利用激光诱导击穿光谱技术,开展了RTV材料的激光诱导等离子体特性研究,为后续利用LIBS技术进行现场检测提供参考。文中主要研究了单脉冲纳秒激光作用下,RTV复合材料的烧蚀特性、等离子体温度、电子数密度、光谱强度与激光诱导击穿光谱(laser-induced breakdown spectroscopy,LIBS)参数的关系,给出了表征老化特性的方法。研究表明,LIBS技术可以有效表征RTV材料的成分,测试其老化厚度、元素变化等状态信息,其现场应用有利于维护输电线路运行安全。展开更多
Objective To evaluate the predictive value of SYNTAX Score II （SS-II） for percutaneous coronary intervention （PCI） in octogenarian （≥ 80 years old） undergoing PCI. Methods ＆ Results Data from three consecutive...Objective To evaluate the predictive value of SYNTAX Score II （SS-II） for percutaneous coronary intervention （PCI） in octogenarian （≥ 80 years old） undergoing PCI. Methods ＆ Results Data from three consecutive years of octogenarian undergoing PCI from Ruijin Hospital （Shanghai, China） was retrospectively collected （n = 308）. Follow up clinical data at one year including all cause mortality, cardiac mortality and main adverse cardiovascular and cerebrovascular events （MACCE） were collected. Patients were stratified according to tertiles of SS-II for PCI： SS-II 〈 26 （n = 104）, SS-II： 27-31 （n = 102）, SS-II 〉 31 （n = 102）. After adjustment for confounding factors, SS-II for PCI was an independent risk factors for all cause mortality （odds ratio： 2.77, 95% CI： 1.13-8.06; P = 0.04）. Kaplan-Meier curves showed higher event rates for all cause mortality and cardiac mortality in higher tertile of SS-II for PCI （Log-Rank test P = 0.002 and P = 0.001, respectively）. SSdl for PCI predicted one year mortality in octogenarian population undergoing PCI. Conclusions In octogenarian, SS-II which incorporated clinical variables with angiographic anatomy variable was suitable in risk stratifying and predicting clinical outcomes at one year.展开更多
Silks are among the most precious ancient and historic artefacts worldwide. While washing removes the natural gum from the fibres during the fabrication of most silk textiles, for a small proportion of historic silks ...Silks are among the most precious ancient and historic artefacts worldwide. While washing removes the natural gum from the fibres during the fabrication of most silk textiles, for a small proportion of historic silks some or perhaps all of the sericin still remains. This paper investigated the effect of sericin coating on the aging of silk fibroin by means of ATR and tensile testing. The results show that sericin can provide some extent of protection from light and heat aging. However, in high humidity environments degummed and ungummed silk aged at the same rate because of leaching of sericin. Silk degraded at faster rate and more extensively in a moist environment. ATR could give very useful information about the aging of silk. The ATR-derived crystallinity index is good at tracing the aging factor and extent of silk deterioration. Alanine and tyrosine within fibroin, as estimated by ATR spectroscopy, are very sensitive to light, but not to heat and water. The ATR absorbance intensity ratio Iamide Ⅲ/ Iamide I is very useful for deterioration evaluation of archaeological silk objects. As a high humidity resulted in the leaching of silk, it is suggested for sericin-coated silk in collections, that not only wet cleaning is harmful, but also that storage or display in a high RH environment would be detrimental.展开更多
文摘硅橡胶复合材料被广泛应用于高压输电外绝缘领域,特别是室温硫化硅橡胶(room temperature vulcanized,RTV),被广泛用作防污闪涂料。目前其检测分析方式以取样后实验室分析为主,尚无可现场检测RTV材料成分及老化状态的技术。该文利用激光诱导击穿光谱技术,开展了RTV材料的激光诱导等离子体特性研究,为后续利用LIBS技术进行现场检测提供参考。文中主要研究了单脉冲纳秒激光作用下,RTV复合材料的烧蚀特性、等离子体温度、电子数密度、光谱强度与激光诱导击穿光谱(laser-induced breakdown spectroscopy,LIBS)参数的关系,给出了表征老化特性的方法。研究表明,LIBS技术可以有效表征RTV材料的成分,测试其老化厚度、元素变化等状态信息,其现场应用有利于维护输电线路运行安全。
文摘Objective To evaluate the predictive value of SYNTAX Score II （SS-II） for percutaneous coronary intervention （PCI） in octogenarian （≥ 80 years old） undergoing PCI. Methods ＆ Results Data from three consecutive years of octogenarian undergoing PCI from Ruijin Hospital （Shanghai, China） was retrospectively collected （n = 308）. Follow up clinical data at one year including all cause mortality, cardiac mortality and main adverse cardiovascular and cerebrovascular events （MACCE） were collected. Patients were stratified according to tertiles of SS-II for PCI： SS-II 〈 26 （n = 104）, SS-II： 27-31 （n = 102）, SS-II 〉 31 （n = 102）. After adjustment for confounding factors, SS-II for PCI was an independent risk factors for all cause mortality （odds ratio： 2.77, 95% CI： 1.13-8.06; P = 0.04）. Kaplan-Meier curves showed higher event rates for all cause mortality and cardiac mortality in higher tertile of SS-II for PCI （Log-Rank test P = 0.002 and P = 0.001, respectively）. SSdl for PCI predicted one year mortality in octogenarian population undergoing PCI. Conclusions In octogenarian, SS-II which incorporated clinical variables with angiographic anatomy variable was suitable in risk stratifying and predicting clinical outcomes at one year.
文摘Silks are among the most precious ancient and historic artefacts worldwide. While washing removes the natural gum from the fibres during the fabrication of most silk textiles, for a small proportion of historic silks some or perhaps all of the sericin still remains. This paper investigated the effect of sericin coating on the aging of silk fibroin by means of ATR and tensile testing. The results show that sericin can provide some extent of protection from light and heat aging. However, in high humidity environments degummed and ungummed silk aged at the same rate because of leaching of sericin. Silk degraded at faster rate and more extensively in a moist environment. ATR could give very useful information about the aging of silk. The ATR-derived crystallinity index is good at tracing the aging factor and extent of silk deterioration. Alanine and tyrosine within fibroin, as estimated by ATR spectroscopy, are very sensitive to light, but not to heat and water. The ATR absorbance intensity ratio Iamide Ⅲ/ Iamide I is very useful for deterioration evaluation of archaeological silk objects. As a high humidity resulted in the leaching of silk, it is suggested for sericin-coated silk in collections, that not only wet cleaning is harmful, but also that storage or display in a high RH environment would be detrimental.
