番红花红T与表面活性剂的作用及其在标记DNA中的应用

对阳离子染料番红花红Ｔ（ＳＴ）在阴离子表面活性剂存在时的溶液状态的吸收光谱和荧光光谱进行了研究。结果表明，低浓度阴离子表面活性剂与ＳＴ形成缔合物，导致ＳＴ的吸收与荧光强度降低；增大表面活性剂的浓度，其分子胶束前预聚集促使染料形成非荧光二聚体，导致荧光急剧猝灭，吸收光谱出现新的特征吸收峰；当表面活性剂浓度大于临界胶束浓度（ＣＭＣ）时，染料二聚体离解，ＳＴ单体增溶于胶团中形成新的高量子产率荧光体。本文     

Physico-chemical Characterization of Mo-Hβ Zeolite Catalysts

A series of Mo-impregnated Hβ samples, with MoO3 loading in Hβ zeolite in the mass fraction range of 0. 5%-6.0%, were studied by means of XRD and IR in order to characterize their structures. Mo/Hβ sampies‘ crystallinity almost linearly decreases with increasing the amount of MoO3 loaded, The IR spectra and XRD patterns suggest that the progressive destabilization of the Hβ zeolite structure is caused by increasing Mo loading in (MoO3 Hβ zeolite). During the calcination, Al2(MoO4)3 formed from the dealumination of Hβ zeolite, causes the substantially partial breakdown of the zeolite framework when the Mo loading in MoO3 Hβ is relatively high.     

Synthesis and electrochemical properties of 2,6-bis（6-aryl-[1,2,4]- triazolo[3,4-b][1,3,4]-thiadiazole-3-yl）pyridines

By the condensation of 2,6-bis（4-amino-5-mercapto-[1,2,4]-triazoles-2）pyridine with aromatic acid in the presence of phosphorus oxychloride. Compounds of 2,6-bis（6-aryl-[1,2,4]-triazolo[3,4-b][1,3,4]-thiadiazole-3-yl）pyridines were synthesized. Their structures were confirmed by IR, ^1H NMR spectroscopies and elemental analysis. Their electrochemical behavior and cyclic voltammogram also were be studied. The results showed that they have high ionization potentials and good affinity.     

Studies of cluster anions C n X− (X=N,P, As,Sb, Bi) produced by laser ablation

A series of cluster anions C _n X^? are produced from laser ablation of appropriate samples, where X is selected as a group-VB element. The recorded mass spectra of these cluster anions display a drastic even/odd alternation on ion intensities: For C _n N^?, only anions with oddn can be observed; For C _n P^? and C _n As^?, cluster anions with evenn are produced but with lower signal intensities; For C _n Sb^?, the signal intensity of clusters does not show even/odd alternation; Finally, for C _n Bi^?, the intensities of cluster anions with evenn are higher than those with oddn. This parity effect can be attributed to the linear structure of the cluster anions, and the parity reversal of C _n X^? from C _n N^? to C _n Bi^? can be explained from the electronegativity decreasing of the heteroatom X as it descends in the group. The Hückel model was applied to account the structural feature of these clusters.     

DNA电化学生物传感器测定水中痕量铅

采用物理涂附法将单链DNA固定到金表面得到ssDNA/Au修饰电极。研究表明,该电极在pH 5,0.2 mol/L NaAc-HAc缓冲底液中,可用于测定水中痕量Pb2 。Pb2 以Pb-DNA络合物的形式吸附在电极上,以示差脉冲伏安法测定Pb2 ,在0.15 V(vsSCE)处有灵敏的氧化峰,其峰电流与Pb2 浓度在5.0×10-8~1.0×10-6mol/L范围内呈良好的线性关系,此法的检测限为2.0×10-8mol/L,该修饰电极的稳定性和抗干扰性都较好。用该电极对饮用水中的Pb进行检测,得到了满意的结果。     

含一价铜配合物的新型双金属钼氧簇合物[5-(4-Br-Ph)-2,4'-Hbpy]2·[CuⅠ(5-(4-Br-Ph)-2,4'-bpy)2]2[Mo8O26]的水热合成及晶体结构

采用水热法合成出一种含一价铜配合物的新型双金属钼氧簇合物[5-(4-Br-Ph)-2,4'-Hbpy]2[Cu(5-(4-Br-Ph)-2,4'-bpy)2]2[Mo8O26],并通过X射线单晶结构分析、红外光谱分析、元素分析以及X射线粉末衍射分析对该化合物的结构进行了表征.结果表明,该化合物属单斜晶系,P21/c空间群,晶胞参数a=1.4411(3)nm,b=1.3924(3)nm,c=2.5183(5)nm,β=99.06(3)°,V=4.990(17)nm3,Z=2;该化合物是由一价铜配合物{Cu(5-(4-Br-Ph)-2,4'-bpy)2}+与{β-Mo8O26}4-簇通过共价配位键连接形成的新型多金属钼酸盐,其中游离的质子化配体作为抗衡阳离子.     

A STUDY OF POLYBUTADIENE SYNTHESIS WITH MoCl_n(OR)_(4-n)-(i-Bu)_2AlOPh AS A CATALYST

The catalytic effect of Mo Cl_n (OR)_(4_n)-(i-Bu)_2AlOPh on the polymerization of butadiene inhydrogenated gasoline is studied (R is alkyl, cycloheptyl, phenyl of C_(4_16)). In this system, the solu-bility and the catalytic activity of the catalyst do not depend on whether the number of carbon atomsin R group is odd or even. The R group with the primary and secondary carbon atom has a fairlygreat influence on the catalytic activity. When R is an alkyl, the catalytic activity increases and therange of Al/Mo values that keeps higher conversion of butadiene is broadened as the size of the Rgroup increases. The content of 1,2-units in the polymer hardly varies with the size of the R group.     

Generic fast gradient liquid chromatography/tandem mass spectrometry techniques for the assessment of the in vitro permeability across the blood-brain barrier in drug discovery

Rapid, generic gradient liquid chromatography/tandem mass spectrometry (LC/MS/MS) assays, designed to accelerate sample analyses, have been developed to keep pace with the productivity of advanced synthetic procedures. In this study, LC/MS/MS was combined with an in vitro, cell-based, blood-brain barrier (BBB) model to evaluate the potential of new chemical entities (NCEs) to cross the BBB. This in vitro assay provides the permeability of discovery compounds across a monolayer of a primary culture of bovine brain microvessel endothelial cells in a fraction of the time that is required for in vivo studies (brain/plasma concentrations), using only 2 mg of the compound. The results are consistent with in vivo brain/plasma concentration ratio data.     

溶剂热法制备Ag/TiO2纳米材料及其光催化性能

以乙醇为溶剂, 钛酸四丁酯为前驱体, 用溶剂热法制备了Ag表面修饰的负载型纳米二氧化钛光催化剂. 利用X射线衍射(XRD)、N₂吸附-脱附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见(UV-Vis)光谱等技术对其进行了系统的表征, 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了不同Ag含量样品的光催化性能. 结果表明: 用溶剂热法制备的样品中TiO₂皆为锐钛矿相, 金属Ag颗粒沉积在TiO₂表面, 粒径为2 nm左右, 比表面积较溶胶凝胶法制备的样品大大增加, 最高可达151.44 m²·g^-1; UV-Vis光谱和光催化实验表明: Ag修饰使TiO₂对光的吸收能力大大增强, 吸收带边红移至可见光区, 亚甲基蓝在该复合材料上的光催化降解反应遵循一级反应动力学模型; 溶剂热法制备样品的光催化性能明显好于溶胶凝胶法制备的样品, 在紫外光和可见光下, Ag摩尔分数为5%的样品表现出最佳的光催化活性.     

结晶／结晶共混体系聚苯硫酸／聚醚醚酮中聚醚醚酮组分的结晶熔融行为──熔融温度的影响

结晶／结晶共混体系聚苯硫酸／聚醚醚酮中聚醚醚酮组分的结晶熔融行为──熔融温度的影响麦堪成，许家瑞，梅震，曾汉民（中山大学材料科学研究所，广州，５１０２７５）关键词聚醚醚酮，聚苯硫醚，结晶／结晶共混物，结晶熔融行为近年来，高性能聚合物共混物如聚砜（ＰＳ...