STUDY OF XPS AND EHMO CALCULATION ON SILATRANE COMPOUNDS

Twenty silatrane compounds with different substituents(R) on the silicon atom are studied by means of X-ray photoelectron spectroscopy(XPS) and EHMO(extended Hückel molecular orbitals) theoretical calculation of the nine compounds in which substituents(R), F, Cl, Br, I, CH_3, H, CH=CH_2, CH_2Cl and CHCl_2, are carried out. By the X-ray photoelectron spectra of the component elements in these compounds, the existence of N→Si dative bond in these molecules is not only confirmed, but the affection of the different substituents on the strength of N→Si dative bond is also obtained. A linear correlation exists between atomic netcharge(Q) obtained by EHMO calculation and the binding energy shifts of N_1_g and Si_(2p) due to different substituents. The calculated bond orders can well predict the effect ou the strength of N→Si dative bond due to the change of substituents in the experiment. Meanwhile, the calculations indicate that the strength of N→Si dative bond in molecules of all substituents is about h     

聚酯—酰胺型MRI造影剂的合成及基弛豫性能研究

通过二乙三胺五乙酸双酸酐分别与乙醇胺、L－丝氨酸及其乙酯、L－酪氨酸及其甲酯、苄酯、正辛酯共聚，合成了七种大分子配体，制备了它们的Gd(Ⅲ）配合物，并进行了表征。测试其中五种水溶性配合物的驰豫性能。结果表明它们具有与Gd(DTPA)相当或更强的弛豫性能。     

等离子体聚合膜的电学性质研究——Ⅱ.腈类单体结构的影响

等离子体聚合膜多为具有高电阻的绝缘体。但是,近年来的研究结果表明,选择合适的单体及采取一些措施,可使等离子体聚合膜从绝缘体至半导体乃至导体的宽范围变化。本文将一些具有不同化学结构的腈类单体进行了等离子体聚合,研究了单体化学结构对所得聚合膜结构及电学性质的影响。聚合方法等同前报。     

Ce^3＋和Eu^2＋共激活氯硅酸锌钙的光谱和敏化特性

合成了Ｃｅ＾３＋和Ｅｕ＾２＋共激活的氯硅酸锌钙「Ｃａ８Ｚｎ（ＳｉＯ４）４Ｃｌ２：Ｃｅ＾３＋，Ｅｕ＾２＋」绿色荧光粉，并报道了它们的漫反射光谱，激光发光谱及发射光谱，观测到氯硅酸锌钙中Ｃｅ＾３＋对Ｅｕ＾２＋离子发光的显著敏化现象。阐述了氯硅酸锌钙中Ｃｅ＾３＋和Ｅｕ＾２＋发光作用缘于Ｃｅ＾３＋和Ｅｕ＾２＋之间的高效无辐一传递。     

侧链为长链烷基醚的聚硅氧烷的合成及其药物控制释放性能的研究

通过硅氢加成法合成了侧链为长链烷基醚的聚硅氧烷及共聚物，研究了其相转变性质以及由其组成的共混硅橡胶薄膜对避孕药物（左旋十八甲基炔诺酮）的释放性能．结果表明：聚硅氧烷的熔融温度随侧链烷基的增长而提高；共聚硅氧烷的熔融温度随较长烷基的比例增加而提高；聚硅氧烷的侧链烷基呈侧向有序性排列．药物分子透过薄膜的速率及其温度依赖性与共混膜中侧链烷基的有序状态有关，即由晶态转变为非晶态时，药物的透过速率加快     

Cd3Al2Ge3O12锗酸盐石榴石中Cr3+的宽发射带和R线

本文首次报道了掺杂不同浓度Cr3+的Cd3Al2Ge3O12锗酸盐石榴石在295K和77K温度下的荧光光谱、Cr3+的鲜红色宽带发射强度与激励功率的关系及荧光衰减.发现在Cr3+的荧光光谱中存在从15400cm-1延伸到11400cm-1附近的宽带、两组R线及R线的Stokes和反Stokes振动光谱.295K时以宽带发射为主,77K时宽带明显减弱,R线发射显着增强.在Cd3Al2Ge3O12石榴石中,Cr3+离子的光谱是由两个性质上稍有差异的Cr3+中心发射组成的.     

IMMUNOFLUORESCENT STUDIES ON MICROTUBULES OF NORMAL AND MALIGNANT HUMAN ESOPHAGEAL CELLS

Anti-tubulin antibody indirect immunofluorescenee microscopy is used in this report. Difference of intracellular microtubule fluorescent staining patterns between normal and malignant human esophageal cells has been observed.Primarily cultured human esophageal epithelial cells display an elaborate array of fluorescent cytoplasmic microtubule filaments, the cytoplasmic microtubule complex(CMTC), in interphase cells and mitotic spindle microtubules in mitotic cells. Malignant esophageal cells from human esophageal carcinoma, ECa109 cells, contain very few cytoplasmic microtubules in interphase cells, but there is no difference of mitotic spindle microtubule fluorescence between normal and malignant cells.The results presented in this report suggest that the diminution of interphase cytoplasmic mierotubules in tumor cells is probably due to the deficiency of microtubule organizing mechanism in interphase tumor cells.     

白光LED固态照明光转换荧光体

报道了当前热点固态照明白光LED对所用光转换荧光体的特殊要求,从发光学和晶场理论出发,提出研发白光LED用荧光体的几种方案和原则.依据多年成果,特别阐述在稀土铝镓石榴石体系,氯硅酸钙及某些钨钼酸盐中,Ce³⁺、Pr³⁺、Tb³⁺、Eu³⁺、Eu²⁺及Mn²⁺离子的发光特性,能量传递,Eu²⁺的特征“阶梯状”光谱以及激活剂在晶体中所占据不同晶体学格位与发光性质的关联性.这些材料都可用于白光LED之中.实践证明,这些基础性研究和原理是研制白光LED用荧光体的基础.光转换荧光体与InGaN蓝光芯片结合可以获得符合严格标准的全色温(2700~8000K)的高显色性白光LED光源.白光LED及InGaN蓝光LED的光电性能与正向电流I_F密切相关,器件散热极为重要.提出的在不同I_F下,LED的相关色温差(ρT_c)可用来表征LED色温变化幅度及稳定性.