利用级数展开的Z扫描理论分析

利用级数展开的方法 ,对薄介质的Z扫描理论进行了分析 ,并对于通常所采用的级数展开和菲涅耳衍射分析方法进行了讨论 ,证明了在分析利用高斯光束对薄介质进行Z扫描测量时 ,即使对于大的非线性相移 ,高斯分解方法和菲涅耳衍射积分方法仍具有等效性 ,澄清了人们认识上的一些误解。同时分析了远场小孔的归一化透射率与积分限的关系 ,并对采用高斯分解方法时级数求和的振荡原因进行了分析和讨论 ,给出了消除振荡所需的最小求和数的判据。针对高斯分解方法和菲涅耳衍射积分方法的使用场合 ,也进行了讨论。根据所得结论 ,可以在具体的实验和理论分析中 。

Extraction of rare earth elements from their oxides using organophosphorus reagent complexes with HNO_3 and H_2O in supercritical CO_2

Direct extraction of metals from solids with complexing agents in supercritical CO2(SC-CO2) has recently attracted interests in separation,purification,recovery,and analysis of metals.In the present study,the static/dynamic extraction of rare earth elements(Nd,Ce) from their oxides(Nd2O3,CeO2) with organophosphorus complexes with HNO3 and H2O in SC-CO2 was investigated.The static extraction efficiency of Nd from Nd2O3 with the tri-n-butylphosphate(TBP)-HNO3 complex could reach 95% under optimized experiment...