5-(对羧基苯偶氮)-8-羟基喹啉与钍的显色反应及应用

研究了钍与5-(对羧基苯偶氮)-8-羟基喹啉(5-CPAHQ)的显色反应条件:在阳离子表面活性剂十六烷基三甲基溴化铵(CTMAB)存在下,pH4.4-5.4缓冲介质中,形成稳定的橙红色络合物,最大吸收波长为490nm,ε=1.10×105L·mol-1·cm-1,钍在0-9μg/25mL范围内符合比尔定律。用TBP萃淋树脂分离,该方法可用于测定矿石中的微量钍。     

偶氮羧Ⅰ催化动力学光度法测定痕量铬的研究

研究了痕量铬(Ⅵ)对高碘酸钾氧化偶氮羧Ⅰ反应的催化作用,发现其在硝酸介质中具有高灵敏的反应,检出限为8.2×10-10g·ml-1,线性范围为0～0.08μg·ml-1。可用于测定水样中的铬。     

氮杂冠醚研究Ⅶ、双仲胺型氮杂冠醚对过渡金属离子的选择性萃取作用

合成了五种新型双仲胺型氦杂冠醚，研究了它们对过渡金属离子进行液—液萃取，并用原子吸收法测定其浓度。实验结果表明：这类冠醚对Ａｇ￣＋、Ｐｄ￣（２＋）、和Ｐｔ￣（４＋）等贵金属离子有较强的选择配位性能，对选择性分离这些金属离子有重要的意义。     

WATER-BLOWN POLYURETHANE RIGID FOAMS MODIFIED BY CHEMICAL PLASTICATION

1. INTRODUCTIONThese years, HCFC-141b may be the most used blowing agent for its useful properties. But, because of its high global warming effect leading to the destruction of the ozone layer, production of HCFC141b has been forbidden. However, there are…     

有机分子与聚电解质静电吸附成膜特性研究

选取多种有机分子及聚电解质，采用静电吸附自组装法制备了聚电解质，聚电解质、聚电解质，有机分子、有机分子，有机分子的复合薄膜，讨论了这些体系的静电吸附成膜特性及其成膜机理．     

脱色阴离子交换剂的再生研究

提出一种新的离子交换剂再生理论，即吸附物的脱附依靠离子交换和络合的协同效应完成．以二价钙离子为再生剂，对糖液脱色用的阴离子交换树脂和阴离子交换纤维进行再生，并与传统的碱性钠盐相比较，研究证明钙离子为再生剂的工艺，具有低成本、无污染的特点．     

共軛高分子的研究——Ⅲ.苯乙炔的热聚合

研究了苯乙炔在1.5,6和10小时的热聚合过程中温度对聚合物分子量的影响。所得结果表明,在150—500°的温度范围内,随着聚合温度的增高,聚合物的分子量都是逐渐降低,表明在高温时聚合物有裂解现象发生。红外光谱显示,400°所得聚合物的光谱吸收峯较之200°聚合物的为小,500°聚合物则出现无明显吸收峯的连续吸收,并且背景升高(“背景效应”)。聚合物的碳氢含量此同样随着聚合温度的升高而增大。这些结果,以及300°以上聚合物在溶液中显示明显的萤光等,被认为是表明聚苯乙炔在高温时发生结构改变,除裂解成小分子外,可能还有环化、脱氢、芳构化等发生,从而由链状结构变为稠环结构乃至三维共轭结构。 聚合物的电子自旋共振测试表明,聚苯乙炔的自由基浓度随下列顺序递增: 300°聚合物<400°聚合物<500°聚合物。     

2型糖尿病患者血清钙镁与甲状腺激素含量变化及临床意义

为了监测 2型糖尿病人血清钙、镁和甲状腺激素含量 ,分析其临床意义及相关性 ,应用放射免疫分析法测定了 1 1 5例 2型糖尿病及 1 5 0例健康人血清甲状腺激素含量。同时用美国杜邦RXL自动生化仪测定了其血清钙、镁含量。结果表明 ,在 2型糖尿病伴有明显并发症者血镁、FT3水平明显降低 (P <0 0 5 ) ,钙镁两种元素与甲状腺激素水平无明显相关性。 2型糖尿病患者适当补镁对预防其并发症是有益的 ,测定FT3 等可作为判断 2型糖尿病严重程度和估计预后的参考指标。     

维生素B12缺乏致神经损害临床分析

维生素B12缺乏多继发于胃肠道外科手术后、贫血及其它内科疾病，其引起的神经系统损害临床表现多样，主要为周围神经损害及亚急性联合变性。测定维生素B1：值、查肌电图等可明确诊断。补充维生素B12治疗有效。     

Oligodeoxyribonucleotide analogues with bridging dimethylene sulfide,sulfoxide, and sulfone groups. Toward a second-generation model of nucleic acid structure

Short DNA analogues with bridging dimethylene sulfide, sulfoxide, and sulfone groups replacing the phosphate diesters (S-DNAs) were synthesized from building blocks prepared via two routes, both starting from D-glucose. Building blocks for RNA analogues were prepared by stereoselective introduction of nucleobase into a 2'-acylated ribose analogue. The ribose analogues were converted to deoxyribose analogues by replacement of a 3'-OH group by a thioacetyl unit, followed by photolytic deoxygenation or radical-based 2'-deoxygenation. DNA analogues joined via CH(2)(-)S-CH(2) units were prepared by S(N)2 displacement of a 6'-mesyl group on one building block using a thiolate nucleophile of another. 4,4'-Dimethoxytrityl protection and deprotection schemes were established for both the thiol and hydroxyl groups. The corresponding sulfoxide DNA analogues were obtained by oxidation with hydrogen peroxide. Sulfone DNA analogues were obtained by oxidation of the sulfide DNA with persulfate or hydrogen peroxide in the presence of a titanium silicate catalyst. The physical properties of several representative oligonucleotide analogues were examined, and interpreted in light of a "second-generation" model for DNA strand-strand recognition, a model that emphasizes the role of the polyanionic backbone in diminishing unwanted tendencies of highly functionalized molecules to form "structure" in solution. Even short sulfide-linked DNA analogues displayed association properties different from those displayed by standard DNA molecules. Complex formation observed with sulfide-linked tetramers by HPLC study in different solvents suggested that the complex is formed using hydrogen bonding. Sulfone-linked dinucleotides display Watson-Crick behavior; the tetramer, however, displayed self-structure. Self-structure and self-aggregation become more prominent as the length of the oligonucleotide analogues increases. The tendency to self-aggregate can be decreased by adding a charged sulfonate group to the 3'-end of the DNA analogue. Features of the second-generation model are important for many areas of nucleic acid chemistry, from the design of nucleic acid therapeutic agents to the search for life on other planets.