家兔动脉粥样硬化模型微量元素谱的计算机多元分析

为了查明微量元素谱与动脉粥样硬化症的关连，用多元分析研究了白兔动脉粥样硬化模型中的生物样品微量元素谱。ＩＣＰ－ＡＥＳ测定动脉粥样硬化模型和对照组的兔器官和 组织中１９种元素。因子分析法处理数据，得到一系列因子得分分布图，各图象表明动脉粥样硬化组与对照组的样品点分布在图上不同区域，且两组样品点可分辨。     

Gamma irradiation of high density poly(ethylene)/ethylene‐vinyl acetate/clay nanocomposites: possible mechanism of the influence of clay on irradiated nanocomposites

A further study on mechanical properties and morphology evolution of high density poly (ethylene)/ethylene‐vinyl acetate/and organically‐modified montmorillonite (HDPE/EVA/OMT) nanocomposites exposed to gamma‐rays (0–200 kGy) has been achieved. The results showed that nanocomposites have superior irradiation‐resistant properties to HDPE/EVA blend in mechanical properties. A transmission electron microscope study verified that a face‐face ordered nanostructure had been induced by gamma‐rays. The aim of this paper is to provide a possible mechanism on how the OMT influences the general properties of irradiated nanocomposites, based on the results of thermal, flammability and mechanical behavior. Three facts are postulated to be responsible for the mechanism. The first is the segregation of nano‐dispersed clay layers not only reduces polymer oxidation but prevents crosslinking reactions. The second is the nanostructure evolution induced by gamma‐rays, which may impart nanocomposites improved elasticity. The last is due to the Hofmann degradation, whose degraded products have opposite roles, accelerating polymer oxidation or promoting crosslinking reactions. These facts interact as well as compete with others. The properties of the nanocomposites strongly depended on the prevalent effects developing with increasing irradiation doses. Copyright © 2005 John Wiley & Sons, Ltd.     

高效液相色谱法分析测定甘草、甘草酸制品及中成药中β－型甘草次酸的含量

报道了应用高效液相色谱法，ＳＰＣ＿（１８）色谱柱，甲醇－水－冰醋酸（７９：２０：１，Ｖ／Ｖ）流动相，ＵＶ２５４ｎｍ，以标准甘草次酸为外标，测定了甘草、甘草酸制品及中成药中甘草次酸的含量。本法适用于测定不同中成药及甘草酸制品中的甘草次酸的含量，方法简便，快速准确。     

染料在纳米TiO2薄膜表面吸附性能的研究

采用溶胶－凝胶法制备纳米TiO2薄膜，并通过吸附染料形成染料／TiO2复合薄膜。分析了染料与TiO2薄膜的相互关系，利用紫外可见、比表面等技术研究染料在纳米TiO2薄膜表面的吸附性能，并计算出TiO2薄膜对染料的最大吸附率。研究表明，染料溶液浓度、温度以及TiO2薄膜浸泡时间对染料吸附量有着显著的影响，染料的吸附性能直接影响着太阳能电池的光电转换效率。     

Heating behavior and crystal growth mechanism in microwave field

A simple microwave solid-state reactor was designed on the basis of a domestic microwave oven by using graphite powder as heating medium. The heating behavior of the reactor was studied by using an on-line computer to monitor the real-time temperature during irradiation. It was found that the temperature (T) was related to the time (t) and that microwave power depended on the duty cycle (x) of microwave irradiation. Two empirical equations were proposed and could be applied to the similar microwave solid-state reactors. Four inorganic layered materials, LiV(3)O(8), KNb(3)O(8), KTiNbO(5), and KSr(2)Nb(3)O(10), were successfully synthesized in the designed reactor at a suitable heating rate and temperature that were fully controlled by the empirical equations. Characterization results of X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman spectroscopy, and scanning (SEM) and transmission (TEM) electron microscopy indicated that the phases of samples prepared by traditional and microwave methods were in good agreement; nevertheless, the heating nature and the morphologies of products were quite different. The samples synthesized in the microwave field had crystallographic defects and showed an incompactly stacking structure of nanosheets. Due to the rapid formation of crystallites and different extended growth rate along the crystal axis of the products in microwave field, the crystal growth mechanism of layered metal oxides was not according to that of the traditional method and is briefly discussed.     

溴酸钾氧化吡口罗红G催化动力学光度法测定痕量NO-2

研究了在磷酸介质中亚硝酸根催化溴酸钾氧化吡口罗红Ｇ而使其褪色，建立了催化动力学光度法测定痕量亚硝酸根的新方法，测定范围为０．２～２０μｇ／ｍＬ，检出限为０．２ｎｇ／ｍＬ，用于食品和水样中的亚硝酸根测定获得满意结果     

Molecular activation analysis for iridium

Molecular activation analysis (MAA) of iridium in geological samples, based on a combination of a newly-developed chemical sequential dissolution method and radiochemical and instrumental NAA, was described to study the distribution pattern and chemical species of iridium in various fractions (soluble carbonate, metal, sulfide, oxide, silicate and acid-insoluble residue) of geological boundary samples, meteorites, ultrabasic rock and volcanic lava. The correlations of Ir with Au, Os, siderophile, chalcophile and lithophile elements were discussed. In addition, the role of kerogen and noble-nugget in the Ir enrichment was scrutinized. The MAA results of Ir favors a mixed effect of asteroid impact, volcanic eruption and post-depositional redistribution to interpret the extant Ir anomaly at Cretaceous-Tertiary boundary layer.     

液相色谱法测定DNA碱基比例及相关条件的优化

应用反相高效液相色谱法测定了鲑鱼精子ＤＮＡ的碱基组成比例，并就有关分析条件进行了优化选择。结果表明：在相关条件中，ＤＮＡ样品的水解条件、标准碱基溶液和ＤＮＡ水解液的ＰＨ值、液相色谱流动相的组成和ＰＨ值是影响各碱基色分离和峰形以及排除杂质干扰的主要因素，在优化选择的条件下测定，各碱基色谱峰分离完全、峰形好且不受杂质干扰，ＤＮＡ样品中各碱基加收量高。高检测信号衰减８倍时，各碱基的最小检测量低于５ｎｇ，     

Co—Mo／Al2O3催化剂的微结构

B_(302Q)型Co-Mo/Al_2O_3催化剂在制备过程中要经过一高温区,活性组分Co、Mo会与载体Al_2O_3发生反应,生成无活性的CoAl_2O_4,CoMoO_4和低活性的CO_9S_8。而活性相MoS_2晶化程度加快,使催化剂活性降低。不过B_(302Q)比C_(25-2-02)(美国),SKK(丹麦)及     

表面附聚薄壳型单分散高效阳离子柱填料的研制及其性能

 报道了一种新的表面附聚薄壳型阳离子柱填料的简易制备方法。首次合成了单分散高效阳离子柱填料。以10μm的单分散聚苯乙烯 二乙烯基苯(PSTDVB)微球为基球,对其表面季铵化,然后均匀附聚一层磺化的阳离子乳胶(0 2μm),即得到阳离子固定相。分别用碱金属及碱土金属离子对用该填料制成的柱的性能进行了测试,结果表明该柱填料对常见阳离子具有很好的分离效果、良好的重现性和低的检测限。