四烷基胺硅酸盐水溶液的研究

三甲基硅烷化气相色谱(TMS-GC)法研究了四甲基胺、四乙基胺、四丙基胺和四丁基胺硅酸盐水溶液中硅酸根离子聚合状态的分布,并对四甲基胺硅酸盐与硅酸钠溶液中硅酸根离子结构的差异进行了比较,从中得到合成沸石分子筛模板剂的作用原理。     

血清锌,体液及细胞免疫与复发性口腔溃疡的实验观察

为了解缺锌是否导致体液及细胞免疫功能失调，诱发口腔溃疡的发生，采用吡啶偶氮萘酚比色法测定了血清中的锌，用免疫荧光法外周血Ｔ淋巴细胞亚群，用免疫比浊法测定血清免疫球蛋白。通过各５０例实验观察表明，口腔溃疡组血清锌偏低，且Ｔ淋巴细胞亚群比值失调，与健康对照组比较，有显著性差异。     

RATE OF REGULATED COPOLYMERIZATION INVOLVING CO_2

在二氧化碳与环氧丙烷的共聚反应中，加入某些调节剂可以得到所需要分子量和官能度的共聚物。这是因为在活泼氢和催化剂活性中心之间有链转移反应发生。我们提出了共聚反应的机理并导出了相应的共聚反应速度方程式，这一机理和速度方程式与实验相符。     

Determination of Trace Manganese by Square‐Wave Stripping Voltammetry

A novel method of determining trace manganese by square‐wave stripping voltammetry with simultaneous plating mercury electrode is described in this paper. Well‐defined stripping peaks of manganese are obtained in H₃BO₄‐NaOH buffer (pH 8.0) and peak currents are in good linear relationship with manganese concentrations in two ranges: from 0.36 nM to 36 nM and from 73 nM to 909 nM. The obtained detection limit is 0.18 nM and relative standard deviation is 2.3% (n=7) under a predeposition time of 90 s. This proposed method has been used for the determination of trace manganese in real plasma samples with satisfiable results and good matching with the results of graphite furnace atomic absorption spectrometry.     

Multiple solutions for a semilinear equation involving singular potential and critical exponent

Variational methods are used to prove the existence of positive and sign-changing solutions for a semilinear equation involving singular potential and critical exponent in any bounded domain.*supported in part by Tian Yuan Foundation of NNSF (A0324612)**Supported by 973 Chinese NSF and Foundation of Chinese Academy of Sciences.***Supported in part by NNSF of China.Received: September 23, 2002; revised: November 30, 2003     

聚碳酸亚丙酯-聚醚聚氨酯的合成与性能

本文报道用CO2与环氧丙烷共聚产物聚碳酸亚丙酯和环氧丙烷均聚物来制备聚氨酯（PPCPOPU）弹性体。探讨了这类弹性体的最佳合成方法，考察了异氰酸酯基与羟基的比值；扩链交联剂用量等因素对弹性体的力学性能的影响。研究了弹性体的形态结构及其性能对配比的依赖关系。发现聚碳酸亚丙酯的耐热性因聚氨酯的形成而得到较大的改善，并发现该类弹性体具有优异的耐水性能。     

天平与化学的发展

本文较系统地介绍了天平的简史及其在化学发展中的作用。     

Multiple solutions for semilinear elliptic equations with Neumann boundary condition and jumping nonlinearities

We obtain nonconstant solutions of semilinear elliptic Neumann boundary value problems with jumping nonlinearities when the asymptotic limits of the nonlinearity fall in the type (Il), l>2 and (IIl), l?1 regions formed by the curves of the Fucik spectrum. Furthermore, we have at least two nonconstant solutions in every order interval under resonance case. In this paper, we apply the sub-sup solution method, Fucik spectrum, mountain pass theorem in order intervals, degree theory and Morse theory to get the conclusions.