信用担保风险的模糊综合评审研究

信用担保机构是连接银行和企业的桥梁，对于改善企业融资环境和拓展银行业务具有重要意义，信用担保风险的评审是担保机构能否生存及有效运行的关键。信用风险的评审机制主观性强，对担保项目进行客观，公正的评审比较困难。本采用模糊数学中的综合判别方法，全面考虑风险评审所涵盖的各种风险指标及其重要度，建立了定性分析与定量分析方法相结合的信用担保风险综合评审模型，为担保机构提供了一种相对科学、客观的评审方法。     

复注及多孔注浆理论研究

针对柱面注浆方式，研究了有关渗透注浆的单孔复注及不同方式布孔时多孔注浆的相互影响等问题，推导出一些有价值的岩体注浆理论公式，可用于指导现场注浆工程的设计与施工．     

The Isoelectric Point and the Points of Zero Charge of Fe-Al-Mg Hydrotalcite-like Compounds

The relation of the isoelectric point (IEP) and the point of zero net charge (PZNC) of the hydrotalcite-like compounds was discussed. It was found that the IEP does not equal to the PZNC and the IEP is higher than the PZNC. The structural positive charges existing in the HTlc,which cause the difference between the IEP and the PZNC. The effects of the structural positive charges of the HTlc on its IEP and PZNC are the same as the specific adsorption of metal cations.     

颗粒增强复合材料热应力分析的双层嵌套模型

建立了一个把增强颗粒球和基体空心球嵌入等效复合介质空腔中的“双层嵌套模型”,研究了颗粒增强材料自高温冷却下来时,不同相中热应力的分布特点。推出了热应力在弹性和弹塑性状态的各种表达式。研究表明,随着温度降低,增强体受到压应力,基体材料中存在的静水应力为拉应力。温度继续下降,将出现自增强颗粒与基体界面向外扩展的屈服区。随增强相体积分数增大,增强颗粒受到的压应力和基体中的静水拉应力减小,增强颗粒与基体界面屈服的起始温差增大,而基体材料全面屈服的温差却减小。     

河南省城市居民消费结构比较研究

本文主要应用聚类分析方法 ,对河南省 17个地市级城市居民的消费结构进行了比较统计分析 ,从而得到了各城市居民消费结构的一些特点和规律 ,并进一步探讨了其消费结构、可支配收入与总消费支出之间的关系     

影响海洋微藻生产麻痹性贝类毒素的重要生态因素

麻痹性贝类毒素是有害赤潮海洋微藻生产的重要毒素种类，本文综述了影响该类毒素的主要生态因素有光，温度，盐度和营养盐4类；弱光对毒素合成有抑制作用。低温下PSP毒素产量高，通过对营养盐吸收机制的离子效应，盐度可影响毒素的生命合成，不同种类和株系对N、P限制的反应有极大差异。     

Heterolytic and Homolytic N-NO Bond Dissociation Energies of N-Nitroso-benzenesulfonylmethylamines in Acetonitrile

Great interests have been accumulated in recent years in the chemistry and biochemistry of nitric oxide (NO) since the remarkable discoveries of its key roles in a wide range of human physiological processes. To elucidate the mechanistic details of NO migration from its donor to its acceptor, it is necessary to determine the Y-NO bind energy that registers the thermodynamic driving force for NO release and capture. In this paper the heterolytic and homolytic N-NO bond dissociation energies [ i. e., △Hhet(N-NO) and △Hhomo(N-NO)] for ten N-nitroso-p-substituted-benzensulfonyl methylamines in acetonitrile are offered, which were obtained from titration calorimetry and thermodynamic cycles, respectively (Scheme 1).     

Optimization of a Cryogenic System at Temperature 2 K for the PKU-FEL Facility

The conceptual design of a cryogenic system at temperature 2 K for the Peking University Free Electron Laser （PKU-FEL） facility is carried out. In order to minimize the scale of the cryogenic system and the running cost, the superconducting accelerator and the superconducting injector will mainly run at a long-pulsed mode. Optimization of the 2-K cryogenic system is carried out based on the heat load estimation and running parameters. Total cooling power of 52.5 W for the long-pulsed mode is necessary for the PKU cryogenic system. The PKU cryogenic system will be the first 2-K system for accelerators in China and will provide experience for similar facilities.     

不同沉淀剂制备的Ag／TS－1催化丙烯直接气相氧化合成环氧丙烷

 在423K、常压固定床石英反应器中，以丙烯直接气相氧化为探针反应，考察了催化剂制备方法、沉淀剂的种类和浓度对制备的Ag／TS－1催化剂催化性能的影响，采用TEM，XRD和UV－Vis等表征手段对Ag／TS－1催化剂进行了分析．结果表明，沉积－沉淀法是最佳的催化剂制备方法，但浸渍法也可制得具有环氧丙烷选择性的催化剂．K2CO3是一种良好的沉淀剂．以K2CO3为沉淀剂，硅钛比为64的TS－1为载体制备的Ag／TS－1催化剂上的丙烯转化率为1．72％，环氧丙烷选择性为98．2％．少量单质银的存在有利于环氧丙烷的生成，除银粒子的分散状态外，银粒子与载体TS－1间的相互作用对提高催化剂的选择性具有决定性作用．     

离子色谱法同时测定水中六种阳离子

研究了用抑制电导离子色谱法一次进样同时测定水中Li^ ,Na^ , NH4^ ,Mg^2 ,Ca^2 的色谱法条件，相对标准偏差小于0．5％，加标回收率在97．5％－104．0％。在水质分析中运用t检验法，比较了用钙、镁离子浓度计算和传统方法测定的总硬度之间是否存在显著性差异。