用光学 光学双共振激光光谱研究了 7Li2 A1Σ+ u 态的Autler Townes (A T)分裂 .一个强的耦合场 (泵浦激光 )激发 7Li2 A1Σ+ u v′ ,J′←X1Σ+ g v″,J″跃迁 ,诱发A1Σ+ u v′ ,J′能级和X1Σ+ g v″ ,J″能级的A T分裂 .另一个探测...用光学 光学双共振激光光谱研究了 7Li2 A1Σ+ u 态的Autler Townes (A T)分裂 .一个强的耦合场 (泵浦激光 )激发 7Li2 A1Σ+ u v′ ,J′←X1Σ+ g v″,J″跃迁 ,诱发A1Σ+ u v′ ,J′能级和X1Σ+ g v″ ,J″能级的A T分裂 .另一个探测激光从A1Σ+ u v′ ,J′能级进一步激发到 4 1Σ+ g 态 .扫描探测激光 ,监测 4 1Σ+ g 态碰撞诱导紫色荧光 ,从而探测A1Σ+ u v′,J′能级的A T分裂 .当耦合场频率偏离共振时 ,激发光谱线出现双重分裂 .在该实验条件下 ,分裂大小和泵浦激光频率偏离共振频率的失谐量成正比 .研究了A T分裂的两条线的相对强度与泵浦、探测光的强度及缓冲气体压力的关系 .展开更多
The security of use for Al-Li alloy will be greatly influenced by the damage degree of plastic deformation within i t at high temperature . Based on continuum damage mechanics theory, the damage e volution of Al-5.4...The security of use for Al-Li alloy will be greatly influenced by the damage degree of plastic deformation within i t at high temperature . Based on continuum damage mechanics theory, the damage e volution of Al-5.44Mg-2.15Li-0.12Zr alloy during plastic deforming at high te mperature is simulated by using the damage evolution model of high temperature p lastic deformation. The changing rule of its inner damage with deformation tempe rature, strain rate and strain is gained in this paper. The equation of damage e volution for high temperature plastic deformation is developed, providing an aca demic basis for the technology of plastic process of Al-Li alloys.展开更多
文摘The security of use for Al-Li alloy will be greatly influenced by the damage degree of plastic deformation within i t at high temperature . Based on continuum damage mechanics theory, the damage e volution of Al-5.44Mg-2.15Li-0.12Zr alloy during plastic deforming at high te mperature is simulated by using the damage evolution model of high temperature p lastic deformation. The changing rule of its inner damage with deformation tempe rature, strain rate and strain is gained in this paper. The equation of damage e volution for high temperature plastic deformation is developed, providing an aca demic basis for the technology of plastic process of Al-Li alloys.
文摘目的研究海南黎族人群心脑血管疾病载脂蛋白E(apo E)基因多态性,探讨其与心脑血管疾病之间的关系。方法应用连接酶检测反应(LDR)技术检测150例心脑血管疾病患者(包括高血压50例、脑梗死50例、冠心病50例)和50名健康对照者的apo E基因多态性分布特征,并进行分析。结果高血压组、脑梗死组、冠心病组及正常对照组均以ε3/3基因型频率最高。脑梗死组ε2等位基因频率最低,与高血压组、冠心病组和正常对照组比较差异有统计学意义(P<0.05),高血压组和冠心病组与对照组比较各等位基因差异均无统计学意义(P>0.05)。结论 apo Eε2等位基因降低可能是黎族人群脑梗死发病的重要因素。