Synthesis,Structure and Luminescence of a Novel 2D Cadmium Coordination Polymer with a Ligand Generated in situ

The hydrothermal reaction of 1,2-dicyanobenzene with NaN3 in the presence of Cd(NO3)2 affords a novel 2D cadmium tetrazolyl-benzoate,{Cd(tzbz)(H2O)}n (H2tzbz is 2-(5-tetrazolyl)-benzoate). The tzbz ligand is generated in situ through the 2+3 Sharpless cycloaddition reaction and hydrolyzation. Its crystal structure was determined by single-crystal X-ray diffraction method. The crystal crystallizes in the orthorhombic system,space group Pbca with a=9.6659(19),b=7.6366(15),c=25.964(5) ,V=1916.5(7) 3,Z=8,Mr=318.57,Dc= 2.208 g/cm3,F(000)=1232 and μ=2.276 mm-1. The Cd(Ⅱ) atom is coordinated by four tzbz ligands and one water molecule to form a severely distorted pentangle bipyramid. While each tzbz ligand connects to four Cd(Ⅱ) atoms in a μ4-η1,η2,η1,η1,η1 coordination mode to construct a 2D architecture of the title complex. Additionally,the title complex exhibits strong fluorescence at room temperature in the solid state.     

加压下中国典型煤二氧化碳气化反应的热重研究

用TG-151加压热天平，测定了三种典型中国煤在二氧化碳气氛下的气化反应活性。结果表明，反应速率与温度的关系符合Arrhenius定律，同时反应速率随着压力的增加而增加，但是随着压力的增加，压力对反应速率的影响越来越小。用下式dx/dt=k0 Pco2/1 αPco2 exp(-Eα/(RT)(1-X)^n模拟实验曲线的结果表明，n值随着温度的升高而降低，随压力的增加而增大。     

Molecular Recognition of Bases and Nucleosides by Mono－substituted Mononuclear Complexes of 1,4,7,10－Tetraaza－cyclododecane

The mononuclear macrocyclic polyamine metal complexes 5a-5e have been shown to form stable 1 : 1 complexes with bases and nucleosides. Their binding constants (K) were determined by UV-visible spectrometric titration. The results show that recognition ability of the complexes 5a--5e for uracil, U (Uridine), dT (Thymidine) is higher than that for the other bases or nucleosides (such as Cytidine, Guanosine, Adenosine). The metal ion also plays an important role for the recognition ability of complexes.     

THE STRUCTURAL BASIS OF THE POOR FIBRIN SPECIFICITY OF UROKINASE(Ⅰ)——KNOWLEDGE-BASED PREDICTION OF KRINGLE STRUCTURES OF UROKINASE AND ITS RELATED PROTEINS

The Kringle-1 structure of plasminogen (PGK-1), the Kringle-2 structure of tissue plasminogen activator (PAK-2) and the Kringle structure of prourokinase (UKK) has been modeled on the basis of the three-dimensional structure of Kringle-1 of prothrombin (PTK-1) at 2.8 resolution. The predicted three-dimensional structure of these Kringles shows that the binding site of PGK-1 is characterized by an apparent dipolar site, the polar parts of which are separated by a hydrophobic region. PAK-2 possesses the anionic center but has not a cationic binding center which might be provided by a guanidinium group from Arg-69 located adjacent to the Arg-71 position. UKK possesses neither the anionic binding center nor the cationic center which are probably the main reason for the poor fibrin specificity of urokinase.     

氧氟沙星的核磁共振波谱性质研究

结合1H, 13C NMR, DEPT, COSY, HSQC, HMBC谱和碳氟偶合裂分行为, 对酸性及碱性溶液中氧氟沙星(Ofloxacin, OFL)的1H和13C谱分别进行归属, 研究了哌嗪环亚甲基构成的AA'BB'复杂自旋体系中各H的化学位移. 发现噁嗪环上的甲基处于直立键; 5H在酸性溶液中化学位移移向低场, 这可能与形成C—H…O弱氢键有关; 在碱性溶液中, OFL的羧基变为羧酸根, 造成羧基和羰基周围碳原子上π电子重新分布, 导致相应C的化学位移和碳氟偶合常数发生明显变化.     

废旧聚酯（PET）的化学循环利用

废旧PET 聚酯可通过化学解聚来实现其循环利用。本文总结了废旧PET 聚酯化学循环利用领域的研究现状, 介绍了目前国内外开发的主要化学解聚工艺方法, 包括水解法、甲醇解聚法、乙二醇解聚法等, 同时对各种工艺过程的优缺点进行了综合比较。     

Nafion修饰玻碳电极伏安法测定痕量铟

报道了一种用Nafion修饰玻碳电极测定痕量铟的新方法。研究了Na-fion膜的有关特性和测定的条件,当富集时间为5 min时,峰电流与In(Ⅲ)浓度在1×10-9~1×10-7mol/L的范围呈良好的线性关系,检出限为1.46×10-10mol/L。该法用于实际水样中痕量铟的测定,平均回收率为98.4%。     

氢氧化镁的结晶习性研究

本文用负离子配位多面体模型探讨了NaOH水热介质中Mg(OH)2晶体的结晶习性。提出了Mg(OH)2的水热改性属溶解-结晶机制、生长基元为Mg(OH)6^4-八面体的观点。Mg(OH)2-NaOH-H2O体系高温热力学计算和电阻在线检测结果间接验证了生长基元论点。理论推导表明：Mg(OH)6^4-八面体的共棱连接方式决定了Mg(OH)2的结晶习性。     

手性聚甲基丙烯酸酯液晶聚合物的合成及相行为的研究

手性聚甲基丙烯酸酯液晶聚合物的合成及相行为的研究向前，张纪宇，张树范（中国科学院化学研究所北京１０００８０）关键词手性液晶聚合物，相行为手性侧链液晶聚合物在侧链中含有不对称碳原子的末端基，使聚合物显示Ｓｔ相．Ｓ？相层中的分子呈倾斜排列而产生自发极化．...     

液/液界面生长法制备一维纳米硒

采用均相反应界面生长法制备了一维结构的纳米硒。在制备过程中,初始硒纳米粒子首先在均相反应液中生成,然后加入与该反应液不互溶的溶剂,使其形成液液界面,硒纳米粒子聚集在界面上生长为一维结构。用扫描电镜、透射电镜、X射线粉末衍射等测试技术对样品进行了表征,并讨论了界面生长的机理及其影响因素。