用传统的固相反应烧结法制备了（1-xmol％）BaTi03-xm01％（Bi0．5Na0.5）TiO3（BBNTx）高温无铅正温度系数电阻（positive temperature coefficient of resistivity，PTCR）陶瓷。x射线衍射表明所有的BBNTx陶瓷形成了单一的四方钙钛矿...用传统的固相反应烧结法制备了（1-xmol％）BaTi03-xm01％（Bi0．5Na0.5）TiO3（BBNTx）高温无铅正温度系数电阻（positive temperature coefficient of resistivity，PTCR）陶瓷。x射线衍射表明所有的BBNTx陶瓷形成了单一的四方钙钛矿结构。SEM分析结果显示随着BNT含量的增加，陶瓷晶粒尺寸减小。空气中烧结的0．2mol％Nb掺杂的BBNT1陶瓷，室温电阻率为～102^Ω·cm，电阻突跳为～4．5个数量级，居里温度为～150℃。氮气中烧结的0．3m01％Nb掺杂的BBNh（10≤x≤60）陶瓷，同样具有明显的PTCR效应，居里温度在180～235℃之间。随着BNT含量的增加，材料的室温电阻率增大，同时陶瓷的电阻突跳比下降。展开更多
AIM: To investigate the pharmacological effects of rice flavone (5,4'-dihydroxy-3',5'-dimethoxy-7-0-β-D-glucopyranosyloxy-flavone, RF) separated from panicle-differentiating to flowing rice on rat experim...AIM: To investigate the pharmacological effects of rice flavone (5,4'-dihydroxy-3',5'-dimethoxy-7-0-β-D-glucopyranosyloxy-flavone, RF) separated from panicle-differentiating to flowing rice on rat experimental hepatic injury. METHODS: Models of rat acute hepatic injury induced by carbon tetrachloride (CCl4) administration, rat hepatic fibrosis induced by thioacetamide, injury of primary cultured rat hepatocytes induced by CCl4, respectively, were established. After treated with RF, content of serum alanine transaminase (ALT), aspartate aminotransferase (AST) and albumin (Alb), hyaluronic acid (HA), the activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and hydroxyproline (Hyp) were measured and liver tissue was observed pathologically by hematoxylin-eosin (HE) staining. Effects of RF on pathological changes, function index, enzyme of scavenging free radicals and blood rheology were evaluated. RESULTS: In model of rat acute hepatic injury induced by CCI4, RF can significantly decrease the contents of serum ALT, AST, increase the content of Alb, improve the dropsy and fat denaturalization of hepatocytes. In model of rat hepatic fibrosis induced by thioacetamide, RF can inhibit the increase of HA, Hyp and whole blood viscosity, and improve the activities of GSH-Px and SOD, and inauricular microcirculation. CONCLUSION: RF has apparent protective effects on hepatic injury by increasing activity of GSH-Px and SOD, scavenging free radicals produced by CCI4, reducing blood viscosity, and improving microcirculation and blood supply.展开更多
文摘用传统的固相反应烧结法制备了（1-xmol％）BaTi03-xm01％（Bi0．5Na0.5）TiO3（BBNTx）高温无铅正温度系数电阻（positive temperature coefficient of resistivity，PTCR）陶瓷。x射线衍射表明所有的BBNTx陶瓷形成了单一的四方钙钛矿结构。SEM分析结果显示随着BNT含量的增加，陶瓷晶粒尺寸减小。空气中烧结的0．2mol％Nb掺杂的BBNT1陶瓷，室温电阻率为～102^Ω·cm，电阻突跳为～4．5个数量级，居里温度为～150℃。氮气中烧结的0．3m01％Nb掺杂的BBNh（10≤x≤60）陶瓷，同样具有明显的PTCR效应，居里温度在180～235℃之间。随着BNT含量的增加，材料的室温电阻率增大，同时陶瓷的电阻突跳比下降。
基金Supported by the National Natural Science Foundation of China, No. 30170105
文摘AIM: To investigate the pharmacological effects of rice flavone (5,4'-dihydroxy-3',5'-dimethoxy-7-0-β-D-glucopyranosyloxy-flavone, RF) separated from panicle-differentiating to flowing rice on rat experimental hepatic injury. METHODS: Models of rat acute hepatic injury induced by carbon tetrachloride (CCl4) administration, rat hepatic fibrosis induced by thioacetamide, injury of primary cultured rat hepatocytes induced by CCl4, respectively, were established. After treated with RF, content of serum alanine transaminase (ALT), aspartate aminotransferase (AST) and albumin (Alb), hyaluronic acid (HA), the activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and hydroxyproline (Hyp) were measured and liver tissue was observed pathologically by hematoxylin-eosin (HE) staining. Effects of RF on pathological changes, function index, enzyme of scavenging free radicals and blood rheology were evaluated. RESULTS: In model of rat acute hepatic injury induced by CCI4, RF can significantly decrease the contents of serum ALT, AST, increase the content of Alb, improve the dropsy and fat denaturalization of hepatocytes. In model of rat hepatic fibrosis induced by thioacetamide, RF can inhibit the increase of HA, Hyp and whole blood viscosity, and improve the activities of GSH-Px and SOD, and inauricular microcirculation. CONCLUSION: RF has apparent protective effects on hepatic injury by increasing activity of GSH-Px and SOD, scavenging free radicals produced by CCI4, reducing blood viscosity, and improving microcirculation and blood supply.
