Ce3+和Tb3+掺杂的稀土硼酸盐玻璃的发光性质

报道Ｃｅ＾３＋和Ｔｂ＾３＋掺杂的硼酸盐玻璃的合成及该系列玻璃的激发和发射光谱性质。在紫外光激发下,玻璃中的Ｃｅ＾３＋发射蓝紫光,Ｔｂ＾３＋发射有特征的绿光,在Ｃｅ＾３＋和Ｔｂ＾３＋共掺杂的体系中,可观察到Ｃｅ＾３＋强烈敏化Ｔｂ＾３＋发光的现象。分析表明,Ｃｅ＾３＋和Ｔｂ＾３＋之间存在辐射能量传递稿铲无辐射能量传递。     

稀土噻吩甲酰三氯丙酮络合物的傅里叶红外光谱

在100—4000 cm^-1范围内,研究了十四个稀土三螯合噻吩甲酰三氟丙酮二水络合物RE(TTA)₃·2H₂O的傅里叶红外光谱。对照前人工作对络合物的谱带作了指认。观察到六个RE—O振动,两个在中红外区(456—475)和489—508cm^-1),四个在远红外区(173—190、213—228、362—374和396—408cm^-1)。中红外区456和489cm^-1附近的谱带随稀土原子序数的变化呈“四分组”效应。羰基及不饱和碳碳键吸收峰都比噻吩甲酰三氟丙酮低60多个波数。     

兴国红鲤的胚胎发育

本文叙述了兴国红鲤(Cyprinus carpio var.singuonensis)胚胎不同发育时期的形态特征,从受精卵到鱼苗孵化出膜被划分为31个发育时期;报导了胚胎各期发育所需时间。兴国红鲤在水体水温为22.39±2.44℃条件下,胚胎发育历时共62小时又58分钟,胚胎发育所需积温为1519.2度时。本文比     

几种新型聚合物配体的合成及其固载化铑催化剂的醛化性能研究

本文使用交联聚苯乙烯为载体合成了几种新型的聚合物配体和固载化铑催化剂,考察了它们对二异丁烯和戊烯-1氢甲酰化反应的催化性能,探讨了催化剂的铑脱落现象。     

Space variable transform method for free vibration analysis of thick cylindrical shell with arbitrary boundary conditions

In this paper, a general analytical method-space variable transform method is presented for solving free vibration problems of thick cylindrical shell with arbitrary boundary conditions. Free vibration characteristics of cantilever thick cylindrical shell are evaluated by the presented method, and the numerical results are compared with the corresponding results of thin shell theory and experimental values. Theoretical analysis and calculating results show that the method presented in this paper has good convergence and accuracy and can be extended to analyze free vibration of beams. plates and shells.     

交流示波极谱滴定的研究(Ⅴ)——丁二酮肟滴定镍

现有的测定镍的容量分析方法很多^[1~3],但准确、简便、快速者不多。目前最常用的是将Ni²⁺先用丁二酮肟沉淀,过滤,洗涤后,重新溶解,再用EDTA滴定,以红紫酸铵或茜素S为指示剂^[4,5],滴定时pH控制要求严格。用丁二肟为滴定剂测镍的安培滴定法也有报导^[6-8],但由于操作麻烦,很少在实际中应用。另外,在氨性溶液中用丁二肟碱性溶液直接滴定镍的办法也有报导^[9],但因使用外指示剂误差较大。     

(NH4)2ZrGe3O9: a new microporous zirconogermanate

A new microporous zirconogermanate, di­ammonium zirconium trigermanate, (NH₄)₂ZrGe₃O₉ (FDZG‐2), analogous to wadeite (K₂ZrSi₃O₉), was hydro­thermally synthesized using ZrO(NO₃)₂·2H₂O as the source of zirconium and 1,4‐di­amino­butane as a structure‐directing agent. Single‐crystal X‐ray diffraction analysis reveals that the framework structure is built up of cyclic trigermanate units crosslinked by ZrO₆ octahedra. The Zr atom lies at a site with symmetry and the unique N atom of the ammonium ion lies at a site with threefold symmetry. Large cages are observed, with two NH₄⁺ cations in each. The structure contains intersecting six‐ and three‐membered ring (6MR and 3MR) channels, but only the 6MR channels can accommodate the NH₄⁺ ions.     

An analysis of the post-buckling of laminated plates of symmetric cross-ply

ＡＮＡＮＡＬＹＳＩＳＯＦＴＨＥＰＯＳＴ－ＢＵＣＫＬＩＮＧＯＦＬＡＭＩＮＡＴＥＤＰＬＡＴＥＳＯＦＳＹＭＭＥＴＲＩＣＣＲＯＳＳ－ＰＬＹＷｅｎｇＺｏｎｇｙｉ（翁宗诒）（ＲｅｃｅｉｖｅｄＭａｒｃｈ６,１９９５,ＣｏｍｍｕｎｉｃａｔｅｄｂｙＺｈｏｕＣｈｅｎｇｔ...     

基于定量结构-性质关系方法预测氨基酸的比旋光度

运用定量结构-性质关系(quantitative structure-property relationsh ip,QSPR)方法对人体必需的氨基酸比旋光度进行了预测,同时运用交互检验(LOO)方法对所建立的模型进行了检验。应用启发式算法对描述符进行筛选并建立线性回归模型,所建立的模型的相关系数(R2)为0.918,但分别用 1、-1代表左旋和右旋的分子手性后,重新建立多元线性回归模型,其相关系数(R2)变为0.970。本研究所建立的QSPR模型为预测手性化合物比旋光度提供了一种有效的新方法。     

THE PROXIMAL RELATION,REGIONALLY PROXIMAL RELATION AND BANACH PROXIMAL RELATION FOR AMENABLE GROUP ACTIONS

In this paper,we study the proximal relation,regionally proximal relation and Banach proximal relation of a topological dynamical system for amenable group acti...