超高相对分子质量聚丙烯腈溶解的研究

通过自制力矩测量仪测量溶胀和溶解过程中超高相对分子质量聚丙烯腈－溶剂混合体系力矩随温度变化情况，采取阶段升温的方法，选择力－温度曲线中力矩开始上升处所对应温度为恒温温度，制得均匀的超高相对分子质量聚丙烯腈（含固量5％）浆液。还初步讨论了力矩峰出现的原因。     

高分子溶液气液平衡的测定与关联

采用静态蒸气吸收法测定了在308.15K时苯，甲苯与聚乙烯（PS），聚甲基丙烯酸甲酯（PMMA），聚醋酸乙烯酯（PVAc)构成的6个单溶剂-高分子系统的气液平衡数据，用UNIQUAC活度系数模型和链状流体状态方程对实验数据进行了关联。     

超高分子量聚丙烯酰胺的水解方法研究

超高分子量聚丙烯酰胺易发生机械降解，化学解降，热降解反应，造成分子量下降，由于分子量高达两千万，只要大分子链上有几个交联点，就会形成水凝胶造成溶解性急剧下降，选择的条件就是尽量避免以上两个副反应的发生，形成超高分子量部分水解的聚丙烯酰胺。     

大麦黄花叶病毒抗性突破株系的分子变异

通过大麦黄花叶病毒 (Ba YMV)抗性突破株系的核酸 RNA1全序列分析并与野生株系比较表明 ,抗性突破株系在病毒复制酶或转运蛋白区域 (6K2 )和核酸 RNA复制酶区域 (NIb)存在二个变异位点 .在这二个位点上抗性突破株系核酸分子编码的氨基酸分别为脯氨酸 (Pro)和苏氨酸 (Thr) ,而野生株系分别为缬氨酸(Val)和丙氨酸 (Ala) .对该两种酶蛋白质二级结构分析显示 ,氨基酸的变异可能导致了蛋白质的结构、功能与性质的改变 ,并且此种变异与抗 Ba YMV冬大麦中抗性基因 ym4的功能丧失有关 ,同时也说明了大麦品种田间致病性的差异与病毒核酸分子中的点突变关系密切 .     

DNA microarray synthesis by using PDMS molecular stamps (Ⅲ)-- Optimization for the reaction conditions

Optimization for the technological processes of fabricating oligonucleotide microarray by the molecular stamping method is studied in this note. Three factors that affect the pressing coupling reactions of the nucleosides are focused on: the stability of the chemical activities of the reaction solutions, the contamination of the remain of the reactive nucleotides among the different spots on the chip, and the influence of the capping reaction on the hybridization result. The experiments show that the acetonitrile solution of tetrazole and nucleoside monomer could maintain sufficient reactive activity for more than 10 h. An effective method has been used and proved to eliminate the residual reactive nucleosides on chip with small molecules containing hydroxyl group. Finally, the capping step-- a regular step in the conventional DNA chemical synthesis can be neglected in our on-chip DNA synthetic process, which would not affect its hybridization results.     

Carcinogenesis of asbestos switched on by inducing cross-linkage between DNA complementary pair bases

Since the beginning of the 1980s, Dai Qianhuan predicted based upon his di-region theory that the carcinogenesis switched on by the so-called physical carcinogenic factors including radiation, asbestos and foreign matter implantation, is just initiated through the cross-linking between DNA complementary pair bases induced by them. In this note, it was evidenced with the DNA filter elution method that the oxygenase activated by asbestos induces the cross-linking between DNA inter-strands and DNA-protein with dosage correlation, in which over 80% of DNA inter-strand cross-link ratio account for the total cross-link ratio. Obviously, both of the cross-linkages are just induced by hydroxyl free radical, HO ·, because the ferrous ion increased the cross-link ratios up to several times through Fenton reaction and vitamin C inhibited the cross-link ratios with factors of 8–9 by destroying the hydroxyl radical. Non-carcinogen but with lower free radical formation energy, pyrene, by culturing with asbestos gave 3–4 times cross-link ratios than the original ratios induced by asbestos only. Estradiol, an endogenous carcinogen, as a bio-electrophilic species but with higher free radical formation energy by culturing with asbestos, gave only 1.2 time cross-link ratios than expected ones. Ferrous ion which can increase HO · concentration through Fenton reaction, increased the ratios to 2–2.5 times in the former case but only 1.2 time in the latter case. Vitamin C, a free radical scavenger, gave a powerful inhibition to the cross-linking with a factor of 8–11 in the former case but a weak inhibition with a factor of 1.2 only in the latter case. So, it is evidenced further that the cross-linkages induced by asbestos are originated from hydroxyl radical. Reasonable structures of the cross-linking products induced by asbestos or hydroxyl radical have been depicted based upon AMI MO theory. These structures have been verified further by a reasonable explanation of the mutational spectrum induced by hydroxyl radical.     

壬基酚聚氧乙烯醚硫酸钠的合成及其二元体系协同效应

研究了由壬基酚聚氧乙烯醚(TX—10)与氨基磺酸反应制备壬基酚聚氧乙烯醚硫酸钠(NPES)的方法，通过对氨基磺酸的用量、反应时间和反应温度等条件的考察，确定了最佳反应条件为酸醚比1．1：1(mol：mol)，反应温度为l10℃，反应时间为lh。在该条件下NPES的收率为94．2％，经提纯后NPES的纯度可达99．6％。NPES与TX—10复配体系的相互作用参数|β^m|＝3～10，属于中等强度协同增效作用，当NPES：TX—10为4：6(mol：mol)时，形成胶团的能力达到最大，NPES：TX—10为7：3(mol：mol)时，降低表面张力的能力达到最大。     

Carbon Molecular Sieve Membrane (CMSM) for Industrial Gas Separation

Membrane separation is an environmental benign technology for 21st century, and is developing quickly to replace the conventional distillation process. Carbon molecular sieve membrane (CMSM) was synthesized through the controlled pyrolysis of polyimide films. The CMSM is symmetric in structure and presents strong sieving effect towards gas molecules of slightly different diameters. The microstructure of CMSM was manipulated through the thermal treatment program and further modified through activation vapor/chemical depositions. It is demonstrated that CMSM can be synthesized/modified for specific gas mixtures, such as O2/N2, CO2/CH4, C3H6/C3H8, and ect. The pore size distribution, relationship between the permeance & selectivity on CMSM for the separation of some gas pairs was also investigated.     

应用DNA分子遗传标记研究药用植物道地性的进展

从药用植物道地性研究中的DNA分子标记、DNA分子标记在道地药材鉴定以及道地性的形成机制研究中的应用等3个方面综述了近年来DNA分子遗传标记技术应用与药用植物道地性研究取得的主要进展,并提出了今后研究中值得注意的问题.     

水溶性杯芳烃在分析化学中的应用

综述了水溶性杯芳烃在分析化学中的研究进展，主要阐述了水溶性杯芳烃在光度法、电化学、色谱分离、毛细管电泳及分子识别等方面的应用。