核酸靶分子与苦参中生物碱成分的非共价作用研究

本文选择合成了与SARS病毒相关的DNA片段作为抗病毒药物筛选的靶分子.利用生物质谱技术,通过对该核酸分子与常见中药苦参中的两种主要生物碱成分的非共价复合作用的研究,探讨该方法作为药物筛选方法的可行性.

有机氨钙催化聚合脂肪族环酯

分别用经环氧丙烷和环氧丙烷/乙腈处理的氨钙催化剂催化聚合了ε-己内酯和L-丙交酯.研究了催化剂浓度、聚合时间、真空度、聚合温度和陈化温度等对聚合收率和聚合物粘均分子量的影响.结果表明,有机氨钙催化剂对ε-己内酯和 L-丙交酯的开环聚合有较高的催化活性 ,在较低的温度下和较短的时间内,即可获得较高的转化率和较高的分子量 ,而且具有一些“准活性聚合”的特点,分子量在一定范围内可控.陈化处理和乙腈的加入可以大大提高聚ε-己内酯的分子量 ,最大分子量达到27×104.

PEMFC催化剂的研究:自制Pt/C电催化剂的性质

研究了一种用于质子交换膜燃料电池(PEMFC)的自制Pt/C电催化剂(标记为THYT-1)的物理化学和电化学性质.将THYT-1电催化剂与E-TEK公司的同类电催化剂的组成、形态及电催化性能进行了比较.单电池测试结果显示,THYT-1的电催化性能优于E-TEK电催化剂.CV测试结果表明CO在这两种电催化剂上的电氧化性能相近;TEM分析表明两种催化剂上Pt晶粒在炭载体上呈均匀分布,平均粒径均为2～3nm;XPS和XRD测试结果表明两种催化剂中Pt主要以金属态存在.这些数据表明THYT-1催化剂的物理化学性质与E-TEK公司的相类似.

Kinetics of reactions of blocked isocyanates

Blocked isocyanates are widely used in many kinds of one-package coatings, powder coatings and adhesives. They have also been used in water-borne polyurethane. The kinetics and mechanism of the reactions of blocked isocyanates are reviewed and two urethane forming reaction mechanisms by which a blocked isocyanate can react with a nucleophile are provided. Furthermore, effects of isocyanate structure, reaction medium, catalyst and functionality on kinetics of blocked isocyanate are discussed in detail.

封闭异氰酸酯几种反应的动力学

封闭异氰酸酯广泛地应用于各种单组分涂料、粉末涂料和胶粘剂中。近年来 ,随着人们对水性聚氨酯的重视和开发 ,封闭异氰酸酯的重视和使用程度进一步加大。本文对封闭异氰酸酯的相关反应的动力学进行了综述 ,对两种不同的反应机理及其动力学的影响因素作了介绍

Modern spectral estimation of ICP-AES

The inductively coupled plasma atomic emission, spectrometry (ICP-AES) and its signal characteristics were discussed using modem spectral estimation technique. The power spectra density (PSD) was calculated using the auto-regression (AR) model of modem spectra estimation. The Levinson-Durbin recursion method was used to estimate the model parameters which were used for the PSD computation. The results obtained with actual ICP-AES spectra and measurements showed that the spectral estimation technique was helpful for the better understanding about spectral composition and signal characteristics.

Simultaneous voltammetric determination of acetophenetidin, aminopyrine, acetaminophenol and aminophenol on a glassy carbon electrode

The voltammetric behaviour of acetophenetidin(A(1)) aminopyrine(A(2)) acetaminophenol(A(3)) and aminophenol(A(4)) was investigated by linear-sweep, differential-pulse, cyclic voltammetry at a glassy carbon electrode. In a medium of 0.1 mol/L NaOH solution, 4 high sensitivity and resolution anodic peaks were obtained. Their peak potentials are about at 0.68 V, 0.51, 0.22 and - 0.06 V( vs. Ag/AgCl). They can be used for direct determination of A(1), A(2),A(3),A(4) in samples respectively. The method is simple and rapid. The mechanism of the electrode reaction was discussed.

多组分有机物在玻碳电极上的伏安法测定

对乙酰氨基苯乙醚、氨基比林、乙酰氨基苯酚、氨基苯酚等4种有机物在玻碳电极上的伏安行为进行了研究.在0.1mol/L氢氧化钠溶液中得4个灵敏度和分辨率良好的阳极氧化峰,E_p分别为0.68,0.51,0.22,-0.06 V(vs.AgCl/Ag)左右,样品不需分离直接测定.20多种有机生化物质不干扰,方法简便快速.并对电极反应进行了探讨.

新型抗爱滋病药物吡喃酮类化合物的三维定量构效关系研究

吡喃酮类化合物是抗爱滋病的一类新药， 本文用CoMFA(Comparative Molecular Field Analysis)方法对19个吡喃酮类化合物的三维构效关系进行了研究， 较详细地探讨了分子的重叠方式， 并选用了其他有关的一些最优条件， 得到满意的结果。

辐射对PP/BR共混体系界面粘接的影响

研究了在多官能团单体异氰尿酸三烯丙酯（ＴＡＩＣ）存在下，辐射对ＰＰ／ＢＲ共混体系的影响，并用ＳＥＭ，ＤＳＣ和动态力学性能等技术对其进行了表征。结果显示，辐射引发ＴＡＩＣ参与的界面反应改变了ＰＰ／ＢＲ的形态结构，增强了两相的界面粘接，改善了相容性，提高了力学性能。

Electrochemical reactions of cyanocobalamin in acidic media

Electrochemical reactions of cyanocobalamin, CN-Cbl[Co(III)], were studied at glassy carbon electrodes in acidic media by means of cyclic voltammetry and differential pulse polarography. It was found that in pH 0 solution, CN-Cbl[Co(III)] exists mainly in the base-off form, {CN-Cbl[Co(III)]}(base-off). It can undergo a one-electron reduction and a follow-up chemical reaction to form {H2O-Cbl[Co(II)]}(base-off). The rate-constant k of the follow-up decyanation reaction is 0.022 s(-1). {H2O-Cbl[Co(II)]}(base-off) is further reduced to obtain H2O-Cbl[Co(I)]. (C) 1997 Elsevier Science S.A.

单叶蔓荆子挥发油成分的GC/MS分析

采用气相色谱／质谱（ＧＣ／ＭＳ）联用技术对山东泰山产单叶蔓荆子挥发油的化学成分进行了分析，分离出３０多个峰，确认了其中２８种成分，占总离子流的９５％以上，并对挥发油的主要化学成分Δ３－蒈烯，用气相色谱／傅里叶红外光谱（ＧＣ／ＦＴＩＲ）法进行了验证。

活体心肌缺血再灌自由基产生和清除的ESR研究

ＥＳＲ和自旅捕捉技术用于研究活体动物犬心肌缺血再灌产生的自由基，ＰＢＮ从冠状静脉血液中捕捉到了ＯＨ自由基，直接地证实了缺血再灌细胞膜损伤的活性氧自由基作用机制；实验还看到一种甾体皂甙药物具有保护心肌细胞．防止自由基损伤的功能．

新型导电高分子材料的导电性与其结构的关系

新型导电高分子材料的导电性与其结构的关系梁洪泽，宋永贤，丁黎明，綦玉臣，李丽霞，景遐斌，王佛松（中国科学院长春应用化学研究所，长春，１３００２２）自Ｗｒｉｇｈｔ首次报道了聚环氧乙烷（ＰＥＯ）－碱金属盐（ＭＸ）配合物的离子导电性以来，有关各种聚合物固体...

聚合物载体－稀土金属络合物的研究 ⅩⅢ．聚［苯乙烯－甲基丙烯酸β（甲基亚硫酰基）乙酯］的结构与其稀土金属络合物催化丁二烯聚合的活性

从测得的竞聚率计算了单体链节在聚［苯乙烯－甲基丙烯酸β（甲基亚硫酰基）乙酯］（ＰＳＭ）中的序列分布。苯乙烯（Ｓ）或甲基丙烯酸β（甲基亚硫酰基）乙酯（Ｍ）的长序列的概率随着ＰＳＭ中相应单体含量的增加而增加。对于Ｓ和Ｍ摩尔分数大致相等的ＰＳＭ，单体链节的长序列分布函数值相接近。用与此结构相近的ＰＳＭ合成的稀土金属络合物，其催化活性不佳。在Ｍ短序列分布和Ｓ长序列分布较高的情况下，络合物的催化活性最好。所得聚丁二烯的微观结构与ＰＳＭ中单体单元的分布无关。