稀土超强酸SO42-/TiO2-Nd2O3催化合成环己烯

环己烯是重要的一种有机合成中间体,具有活泼的双键,作为有机化工原料,可广泛应用于医药、农药、农用化学品、饲料添加剂、聚酯和其他精细化学品的生产。人们曾对环己醇脱水制环己烯反应使用过多种酸性催化剂及固体催化剂,固体超强酸就是其中之一,虽然已有许多关于固体超强酸应     

Novel CuS nanofibers using organogel as a template: controlled by binding sites

A new cholesterol organogelator 1 was synthesized, which was confirmed as an effective gelator for various organic solvents and could self-assemble into network fibers in some organic solvents. Moreover, gelator 1 could act as templates for the synthesis of various CuS nanofibers with different helical pitches. For example, when H(2)S was used as the sulfur source, straight and bending helical CuS nanofibers with a pitch of 100-200 nm could be fabricated in butyl acetate and benzene-butanol gel systems, respectively, while bending CuS nanofibers with a similar helical pitch (ca. 50 nm) could be obtained when thioacetamide was used as the sulfur source in both gel systems. It was first found that the morphologies of inorganic nanofibers could be controlled by the binding sites between the inorganic precursor and the organogel.     

New cholesteric liquid crystals induced by intermolecular hydrogen bonding

New cholesteric liquid crystals induced by intermolecular hydrogen bonding between 3-cholesteryloxycarbonylpropanoic acid (MCB) and 4-(4-alkoxybenzoyloxy)-4-stilbazoles ( n SZ); between MCB and N -(4-pyridylmethylidiene)anilines ( n -PMA) were prepared. Their liquid crystalline properties were investigated by DSC, polarized optical microscopy and X-ray diffraction. Cholesteric and smectic phases were observed. In order to study the influence of covalent and non-covalent bonding upon the liquid crystal behaviour several new covalently bonded N -\[4-(3-cholesteryloxycarbonylpropionyloxy)benzylidiene]-4-alkoxy anilines were investigated.     

KMnO4-甲醛-茚三酮化学发光体系的研究

在甲醛存在下,KMnO4与茚三酮能够发生化学发光反应,产生很强的化学发光.据此采用流动注射技术,建立了一种利用KMnO4-甲醛-茚三酮化学发光体系测定茚三酮的方法.方法的检出限为3×10-8 g/mL;相对标准偏差为1.1%(4.0×10-6g/mL茚三酮,n=11);线性范围为1.0×10-7～2.0×10-4 g/mL.本法已用于样品中茚三酮的测定.     

Synthesis, Crystal Structure and Electrochemical Properties of One-dimensional Chain Coordination Polymer [Co（Ⅱ）（C6H5CH=CHCOOH）2（4,4＇-bipy）（H2O）5]n

A one-dimensional chain coordination polymer [Co（Ⅱ）（C6H5CH--CHCOOH）2（4,4＇- bipy）（H20）5]n has been synthesized with cinnamylic acid, 4,4＇-bipy and cobaltous chloride as raw materials. Crystal data for this complex： monoclinic, space group P21/c, a = 1.1481（3）, b = 1.1230（2）, c = 1.1759（3） nm, β = 97.054（4）^o, V= 1.5046（6） nm^3, Mr= 617.50, Dc = 1.363 g/cm^3, Z = 2, ,u（MoKa） = 0.627 mm^-1, F（000） = 646, S = 1.062, R 0.0443 and wR = 0.1178. The crystal structure shows that two neighboring cobalt（ID ions are linked together by one 4,4＇-bipy, and the whole complex molecule adopts a one-dimensional chain structure. Each cobalt（H） ion is coordinated with two nitrogen atoms from two 4,4＇-bipy molecules and four oxygen atoms from four water molecules, giving a distorted octahedral coordination geometry. The electrochemical properties were analyzed by combining with the crystal structure.     

电感耦合等离子体质谱法测定镀锌钢板中痕量铬和铅

研究了电感耦合等离子体质谱法测定镀锌钢板中痕量杂质元素铬和铅,可测定低至10-5%数量级的痕量铅和铬.用国家标准物质验证了方法的准确度,测定值与标准值吻合,回收率为95%～106%,相对标准偏差小于5%(n=7).     

Facile preparation and characterization of novel oleanane-type triterpene functionalized β-cyclodextrin conjugates

Four water-soluble β-CD-pentacyclic triterpene conjugates were synthesized via ester and amide linkages. All the conjugates showed lower hydrophobicity (AlogP) than their parent.     

Fabrication of Active Horseradish Peroxidase Micropatterns with a High Resolution by Scanning Electrochemical Microscopy

We used a new reactive species OH^? to fabricate active horseradish peroxidase (HRP) micropatterns with a high resolution by scanning electrochemical microscopy (SECM) coupled with a carbon fiber disk electrode as the SECM tip. In this method, except for active HRP micropatterns predesigned other regions on a HRP‐immobilized substrate were deactivated by OH^? generated at the tip held at ?1.7 V in 1.0 mol/L KCl containing 2.0×10^?3 mol/L benzoquinone (BQ) (pH 8.0). The feedback mode of SECM with a tip potential of ?0.2 V was used to characterize the active HRP micropatterns in 1.0 mol/L KCl containing 2.0×10^?3 mol/L BQ and 2.0×10^?3 mol/L H₂O₂.     

Gold Nanoparticle-based Layer-by-Layer Enhancement of DNA Hybridization Electrochemical Signal at Carbon Nanotube Modified Carbon Paste Electrode

Nanoporous materials have been widely applied to biosensor investigation. Recently, Guo et al. have investigated the mesoporous materials modified carbon paste electrode for rapid cTnI (cardiac troponin I) detection with enhanced sensitivity1-3. However, …     

基于原位体积加成制备导电线路的研究

本文提出一种制备导电电路的方法。以纳米铜为导电填料，以光固化树脂为连接剂，制备含铜光固化油墨，利用丝网印刷方法获得含有纳米铜的图案，利用铜与银盐间的置换反应，将铜纳米粒子图案通过原位体积加成转化为导电银图案。研究结果表明，铜图案不具有导电性，而置换反应生成的银图案具有导电性，且导电能力受铜含量、银盐浓度、光照时间、浸泡反应时间等因素影响，本实验中获得的最高电导率为1.25×10⁵ S/m，导电线路具有良好的耐弯曲、耐疲劳性能，同时兼具优异的可修复性能，为导电线路的制备提供了常温下简单有效、成本低廉的实现方法，具有重要的参考价值。