The combustion behavior of Ti-Al-Mo-Zr-Sn-W alloy(TC25G)was studied in a high-temperature and high-speed air flow environment using the laser ignition method combined with ultra-high temperature infrared thermometer,s...The combustion behavior of Ti-Al-Mo-Zr-Sn-W alloy(TC25G)was studied in a high-temperature and high-speed air flow environment using the laser ignition method combined with ultra-high temperature infrared thermometer,scanning electron microscope,X-ray diffractometer,and transmission electron microscope.The burn-resistant performance of TC25G and TC11 alloys was compared.Meanwhile,the microstructural characteristics,crystal structure,and formation mechanism of the combustion products of TC25G alloy were analyzed in detail.The results show that the high-temperature and high-speed air flow promotes combustion within the air flow temperature range of 200–400℃and the air flow velocity range of 0–100 m/s.The combustion path advances along the direction of the air flow.The combustion of TC25G alloy mainly relies on the diffusion of the oxygen and the expansion of the combustion area caused by the movement of the melt.Based on the microstructure and composition of combustion product,it can be divided into the combustion zone,the melting zone,and the heat affected zone.During combustion,the formation of microstructures is closely correlated with the behavior of alloying elements and their selective combination with O.The major oxidation products of Ti are TiO and TiO_(2).The oxides formed by Mo and W hinder the movement of the melt during the combustion.Al and Zr tend to undergo internal oxidation.Al_(2)O_(3)precipitates on the surface of ZrO_(2),forming a protective oxide layer that inhibits the inward diffusion of O.Moreover,the element enrichment at the interface between the melting zone and the heat affected zone increases the melting point on the solid side,hindering the migration of the solid-liquid interface.展开更多
为探讨病毒如何利用宿主细胞自噬机制进行复制和传播提供研究模型,本研究利用CRISPR/Cas9系统构建ATG5基因敲除细胞系。首先针对非洲绿猴肾细胞(Vero)的ATG5基因设计靶向sgRNA序列,并将其连接到慢病毒载体中,包装得到重组慢病毒,用其感...为探讨病毒如何利用宿主细胞自噬机制进行复制和传播提供研究模型,本研究利用CRISPR/Cas9系统构建ATG5基因敲除细胞系。首先针对非洲绿猴肾细胞(Vero)的ATG5基因设计靶向sgRNA序列,并将其连接到慢病毒载体中,包装得到重组慢病毒,用其感染Vero-SN细胞,经过筛选得到ATG5基因敲除的亚克隆细胞系。利用TCID_(50)和Western-blot技术检测小反刍兽疫病毒(peste des petits ruminants virus,PPRV)分别在Vero-SN细胞和ATG5基因敲除细胞系中的复制能力。结果表明,本研究成功建立了VeroSN-ATG5KO细胞系,且抑制细胞自噬不利于病毒复制。该基因敲除细胞系的建立为后续探究病毒与自噬蛋白的相互作用及分子机制提供了试验材料。展开更多
基金China“Ye Qisun”Science Foundation Project of National Natural Science Foundation(U2141222)Innovation Fund(8F231527Z)。
文摘The combustion behavior of Ti-Al-Mo-Zr-Sn-W alloy(TC25G)was studied in a high-temperature and high-speed air flow environment using the laser ignition method combined with ultra-high temperature infrared thermometer,scanning electron microscope,X-ray diffractometer,and transmission electron microscope.The burn-resistant performance of TC25G and TC11 alloys was compared.Meanwhile,the microstructural characteristics,crystal structure,and formation mechanism of the combustion products of TC25G alloy were analyzed in detail.The results show that the high-temperature and high-speed air flow promotes combustion within the air flow temperature range of 200–400℃and the air flow velocity range of 0–100 m/s.The combustion path advances along the direction of the air flow.The combustion of TC25G alloy mainly relies on the diffusion of the oxygen and the expansion of the combustion area caused by the movement of the melt.Based on the microstructure and composition of combustion product,it can be divided into the combustion zone,the melting zone,and the heat affected zone.During combustion,the formation of microstructures is closely correlated with the behavior of alloying elements and their selective combination with O.The major oxidation products of Ti are TiO and TiO_(2).The oxides formed by Mo and W hinder the movement of the melt during the combustion.Al and Zr tend to undergo internal oxidation.Al_(2)O_(3)precipitates on the surface of ZrO_(2),forming a protective oxide layer that inhibits the inward diffusion of O.Moreover,the element enrichment at the interface between the melting zone and the heat affected zone increases the melting point on the solid side,hindering the migration of the solid-liquid interface.
文摘为探讨病毒如何利用宿主细胞自噬机制进行复制和传播提供研究模型,本研究利用CRISPR/Cas9系统构建ATG5基因敲除细胞系。首先针对非洲绿猴肾细胞(Vero)的ATG5基因设计靶向sgRNA序列,并将其连接到慢病毒载体中,包装得到重组慢病毒,用其感染Vero-SN细胞,经过筛选得到ATG5基因敲除的亚克隆细胞系。利用TCID_(50)和Western-blot技术检测小反刍兽疫病毒(peste des petits ruminants virus,PPRV)分别在Vero-SN细胞和ATG5基因敲除细胞系中的复制能力。结果表明,本研究成功建立了VeroSN-ATG5KO细胞系,且抑制细胞自噬不利于病毒复制。该基因敲除细胞系的建立为后续探究病毒与自噬蛋白的相互作用及分子机制提供了试验材料。
