Ru（bipy）2（dppz）^2＋ 与DNA相互作用的光谱研究

利用荧光和紫外可见吸收光谱研究了Ru(bipy)2(dppz)^2 与DNA之间的插入键合作用。结果表明,Ru(bipy)2(dppz)^2 是通过dppz要与体插入到DNA的双螺旋结构中。而且,一定浓度的Fe( CN)^4-6和NaCl对Ru(bipy)2(dppz)^2 －DNA复合物的 荧光无猝灭作用,这一结果也 证实了Ru(bipy)2(dppz)^2 与DNA之间的插入键合作用。     

A highly active neodymium chloride isopropanol complex/modified methylaluminoxane catalyst for preparing polyisoprene with high cis-1,4 stereospecificity and narrow molecular weight distribution

<正>Neodymium chloride isopropanol complex(NdCl_3·3~iPrOH) activated by modified methylaluminoxane(MMAO) was examined in isoprene polymerization in hexane,with regards to Nd compounds,aluminum(Al) compounds,[Al]/[Nd] ratio,polymerization temperature and time.NdCl_3-3~iPrOH exhibited high activity producing polymers featuring high cis-1,4 stereospecificity(96%),very high molecular weight(M_n1.0×10~6) and fairly narrow molecular weight distribution (MWD,M_w/M_n2.0) simultaneously.In comparison,neodymium isopropoxide also showed high activity providing polymers with narrow MWD(M_w/M_n = 2.07),but somewhat low cis-1,4 content(ca.92%),while neodymium chloride had no activity under present polymerization conditions.The Al compounds affected the polymer yield in the order of Al(i-Bu)_3MMAOAl(i-Bu)_2H.MMAO as cocatalyst afforded polyisoprene with high M_n over 1.0×10~6,whereas as stronger chain transfer agent than MMAO,Al(i-Bu)_3 and Al(i-Bu)_2H yielded polymers with low M_n(1.0×10~5-8.0×10~5). NdCl_3·3~iPrOH/MMAO catalyst showed a fairly good catalytic activity even at relatively low[Al]/[Nd]ratio of 30,and the produced polymer remained high cis-1,4 content of 95.8%along with high M_n over 1.0×10~6 even at elevated temperatures up to 70℃.The polymerization rate is of the first order with respect to the concentration of isoprene.The mechanism of active species formation was discussed preliminarily.     

有机污染物水解速度常数与腐殖质浓度定量关系的建立及验证

水解是有机污染物转化降解的重要途径.天然水体中的腐殖质影响有机化合物的水解速度常数,使之与蒸馏水缓冲系统中的测定值有较大差别.本文推导并验证了腐殖质浓度与水解速度常数的定量关系,测定了腐殖质与有机化合物的缔合系数.     

Trihydroxybenzoic Acid Dimer-induced Apoptosis Effects in vitro

IntroductionTrapabispinosd roxbis a kind of traditional Chineseherbal medicine which is the fruit of water chestnutplant in the water chestnut family.It has functions ofclearing away summer-heat,allaying fever,dispersingdampness,dispelling pathogenic wind,nourishing qi,invigorating the spleen,relieving alcoholism,etc.[1].It contains various mineral elements and amino acidsand has a high edibility and importance as medicine.The research results in recent years show that it alsohas an anti-tumo…     

Construction and Evaluation of Merged Pharmacophore Based on Peroxisome Proliferator Receptor-Alpha Agonists

Pharmacophore is a commonly used method for molecular simulation, including ligand-based pharmacophore (LBP) and structure-based pharmacophore (SBP). LBP can be utilized to identify active compounds usual with lower accuracy, and SBP is able to use for distinguishing active compounds from inactive compounds with frequently higher missing rates. Merged pharmacophore (MP) is presented to integrate advantages and avoid shortcomings of LBP and SBP. In this work, LBP and SBP models were constructed for the study of peroxisome proliferator receptor-alpha (PPARα) agonists. According to the comparison of the two types of pharmacophore models, mainly and secondarily pharmacological features were identified. The weight and tolerance values of these pharmacological features were adjusted to construct MP models by single-factor explorations and orthogonal experimental design based on SBP model. Then, the reliability and screening efficiency of the best MP model were validated by three databases. The best MP model was utilized to compute PPARα activity of compounds from traditional Chinese medicine. The screening efficiency of MP model outperformed individual LBP or SBP model for PPARα agonists, and was similar to combinatorial screening of LBP and SBP. However, MP model might have an advantage over the combination of LBP and SBP in evaluating the activity of compounds and avoiding the inconsistent prediction of LBP and SBP, which would be beneficial to guide drug design and optimization.     

NEWTON METHOD FOR SOLVING A CLASS OF SMOOTH CONVEX PROGRAMMING

1ConvexProgrammingandExactPenaltyFunction Weconsiderthefollowingconvexprogramming:(P)minf(x)s.t.x∈S={x∈Rn:gi(x)≤0,i=1,…,m}.SupposethatSisacompactset.ThusthereexistsalargeboundedboxX,suchthatS={x∈Rn:gi(x)≤0,i=1,…,m}intX.Assumethatf(x),gi(x),i=1,…,m     

新型生物芯片扫描仪光学系统设计

传统生物芯片检测扫描仪光学系统的特点是分辨率高、孔径大,但工作距离较短,一般只有1mm左右,有的甚至更短。由于组织芯片、细胞芯片等需要进行实时添加药物与试剂,工作距离越大操作越方便,因此扫描仪光学系统需要具有很长的工作距离。介绍了一种用于组织芯片、细胞芯片扫描仪的新型光学系统。该光学系统的工作距离为15mm,数值孔径为0 67,物方分辨率<350nm。这种新型光学系统首先是要确定物镜的光学结构,然后再通过计算机辅助设计方法设计出成像质量优良的物镜。     

高阶变系数线性微分方程的一些新的可积类型

借助双变换—未知函数的变换和自变量的变换,将几类高阶变系数线性微分方程化为相应的常系数线性微分方程,从而顺利求得它们的通解,得到了变系数线性微分方程新的可积类型,所得结果极大地推广了著名的Euler方程及前人的一些的工作,并给出了相应的实例加以佐证.     

聚能装药的多点环形起爆器性能测试及其应用

对聚能装药用多点环形起爆器的同步性能和环形起爆的聚能装药侵彻钢筋混凝土的侵彻威力进 行了研究。应用高速摄影技术和光纤探针技术测量了多点环形起爆器各点输出的同步性,结果表明环形起爆 器各点输出同步性好,时间差最大不超过0.1s;聚能装药对钢筋混凝土的侵彻威力实验结果表明,采用多点 环形起爆器的聚能装药对钢筋混凝土的侵彻威力比点起爆的有较大提高。