对西方数学直观的评析

本文从数学方法论的角度,具体论述和评析了西方数学直观随数学发展的不同阶段所表现出的特点和演变方式。     

Chemical synthesis and electric properties of the conducting copolymer of aniline and o‐aminophenol

A copolymer, poly(aniline‐co‐o‐aminophenol), was prepared chemically by using ammonium peroxydisulfate as an oxidant. The monomer concentration ratio of o‐aminophenol to aniline strongly influences the copolymerization rate and properties of the copolymer. The optimum composition of a mixture for the chemical copolymerization consisted of 0.3 M aniline, 0.021 M o‐aminophenol, 0.42 M ammonium peroxydisulfate, and 2 M H₂SO₄. The result of cyclic voltammograms in a potential region of ?0.20 to 0.80 V (vs.SCE) indicates that the electrochemical activity of the copolymer prepared under the optimum condition is similar to that of polyaniline in more acid solutions. However, the copolymer still holds the good electrochemical activity until pH 11.0. Therefore, the pH dependence of the electrochemical property of the copolymer is improved, compared with poly(aniline‐co‐o‐aminophenol) prepared electrochemically, and is much better than that of polyaniline. The spectra of IR and ¹H NMR confirm that o‐aminophenol units are included in the copolymer chain, which play a key role in extending the usable pH region of the copolymer. The visible spectra of the copolymers show that a high concentration ratio of o‐aminophenol to aniline in a mixture inhibits the chain growth. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5573–5582, 2007     

中国现当代寓言创作的缺失

中国现当代寓言创作虽然取得了很大的成就,但相当一部分作品从立意到表现却存在着脱离讽喻性、失去故事性、忽视原创性的倾向。中国现当代寓言的创作应在这些方面有所改进。     

Chemical reactivity of hypervalent silicon compounds: The local hard and soft acids and bases principle viewpoint

The silicon atom may increase its coordination number to values greater than four, to form pentacoordinated compounds. It has been observed experimentally that, in general, pentacoordinated compounds show greater reactivity than tetracoordinated compounds. In this work, density functional theory is used to calculate the global softness and the condensed softness of the silicon atom for SiH _n F_4−n and SiH _n F _5−n ¹⁻ . The values obtained show that the global and condensed softness are greater in the pentacoordinated compounds than in the tetracoordinated compounds, a result that explains the enhanced reactivity. If the results are analysed through a local version of the hard and soft acids and bases principle, it is possible to suggest that in nucleophilic substitution reactions, soft nucleophiles preferably react with SiH _n F _5−n ¹⁻ , and hard nucleophiles with SiH _n F_4−n .     

论"规矩"与"方圆"语境下干部践行荣辱观的文化自觉

在全社会树立社会主义荣辱观，重点和关键在于干部。广大干部要从传统与现代、整体与个人、大是与小非、内质与外化等关系层面的理解上，形成自觉践行荣辱观的文化自觉；要以“规矩”与“方圆”的逻辑理念构建干部新形象，即努力铸造一种内在的恪守原则性、纪律性的“内方”形象，外在的体现和谐性、团结性的“外圆”形象，以及整体优化的原则性、和谐性兼备的“方圆统一”的道德人格喻义形象。     

Structure of norbornene-fused 3,1-oxazine double cycloadducts

Pentacyclic isoxazolines were obtained by the cycloaddition of benzonitrile oxide to norbornene-azetidinone-fused 3,1-oxazines. The constitutions of two of the isomers obtained, and the configurations and conformations of all products, were determined by means of ¹H and ¹³C NMR spectroscopy and DNOE experiments.     

加强高校预算管理

目前,高校预算管理存在着认识不全面、编制不完整、预算执行监督和管理不到位及与政府推行的财政体制改革不适应等问题.只有不断加强预算管理,积极探索,才能摸索出符合预算管理政策和财政体制改革,适应学校发展的预算管理模式.     

Electrochemical studies of glutathione monolayer assembled on a polycrystalline gold electrode

The glutathione (GSH) monolayer and complex monolayer of GSH-metallic ion on polycrystalline gold electrode were studied by using K₃Fe(CN)₆ as the redox probe. As for the GSH monolayer, it was found that the metallic ions could open the ion-gate in the monolayer dramatically in the order La³⁺> Pb²⁺>>Ba²⁺>Ca²⁺ whereas Zn²⁺ ion closed the ion-gate. The complexes of GSH-metallic ions were capable of self-assembling the different kind of monolayer. All the differences were related to the structural configuration of the anchored GSH molecule, which changed with different metallic ions or pH. Biography:Fang Cheng (1971-) male, Ph. D, research direction: electroanlysis.     

浅谈高校公用计算机机房的建设与管理

本文探讨了高校计算机机房如何进行软硬件配置才能适应教学的管理，发挥出计算机这一现代化武器的优势。     

小型建筑施工企业机械设备维修保养制度探析

小型建筑施工企业建立科学合理的机械设备维修保养制度，是保证工程质量和提高企业经济效益的重要环节。