水解聚合铝溶液中Al30形态的研究

水解聚合铝形态一直是分析、催化、土壤、地球化学、新材料、环境科学和生物毒理学等众多领域研究的前沿和热点。Keggin 结构的Al₃₀ 形态是迄今为止发现的电荷最高的水解铝聚合阳离子,具有独特的分子结构和纳米分子尺寸,它对催化化学、新型功能材料、高效絮凝剂的开发以及铝的水解聚合转化规律研究具有重要意义。本文主要论述了Al₃₀形态的形成、形态分析方法、结构模型以及形成机理等方面的最新研究进展,并对水解聚合铝溶液的研究发展趋势进行了展望。     

32Cr2MoVA合金结构钢标准物质的研制

本标准物质系合金钢。主要成份有碳、硅、锰、磷、硫、铬、镍、钼、钒,同时还含有锡、铅、砷、锑、铋等微量元素,每种元素成份都具有良好的线性关系。它可作为量值传递和仲裁分析的依据,同时也可用于校验分析仪器与分析方法的正确性和可靠性。     

Analysis of Hydrolysis Reaction of N-Phosphoryl Phenylalanine by HPLC-ESI-MS／MS

Hydrolysis procedure of N-phosphoryl phenylalanine (DIPP-Phe) was studied by HPLC-ESI-MS/MS. The results showed that (HO)(i-PrO)P(O)Phe was the main intermediate and the hydrolysis of DIPP-Phe also occurred through a penta-coordinate transition state.     

荧光钙探针试剂及其在生物分析中的应用

本文评论了荧光钙探针试剂合成、性质、结构和生物分析应用方面的进展。各种典型的荧光钙探针试剂均已分别加以讨论。     

痕量铜的合并带法流动注射分析——Fe~(3+)-S_2 O_3~(2-)-Cu~(2+)催化体系

本文基于 Cu~(2+)对三价铁离子与硫代硫酸盐反应生成深紫蓝色物质的褪色反应的催化作用采用流动注射合并带技术,建立了痕量铜(Ⅱ)的快速分析方法。方法的线性范围在0～350μg/L 检出限为10μg/L,相对标准偏差为1.68％,进样频率可达100样次/小时,具有很高的选择性。     

Photo-and Electro-luminescence of the New Ternary Europium(III) Complex

In recent years, the interest in developing luminescent lanthanide complexes has been greatly stimulated by their potential use in electroluminescent displays1. Europium complexes appear most attractive in view of the high photoluminescent efficiency and the high monochromatic red light that are widely exploited in full-color displays2. It has been approved that the second ligand plays an important role in europium complexes, the synergistic complexation of the second ligand can not only lead …     

胶束增溶(增敏)配合体系的高效液相色谱研究 Ⅴ.Fe、Co、Pd-3,5-diBr-PADAT-SLS 体系

本文用反相高效液相色谱法研究了铁、钴,钯-3,5-diBr-PADAT-SLS体系。在pH5.5的HAc-NaAc介质中,七种金属离子可与试剂生成配合物。用Spherisorb 5 ODS柱,含有4.02×10~(-2)mol/L KCl和0.06mol/L pH3.0HAc-NaAc甲醇/乙腈/水(83/0.5/16.5)溶液作为流动相,分离出了Fe~(2+)、Co~(2+)和Pd~(2+)配合物。对分离机理进行了初步研究。建立了铁、钴、钯的同时测定的HPLC-光度法。用于对虾饵料中铁、钴的测定,结果令人满意。     

新鄂西香茶菜素的X射线结构分析

新鄂西香茶菜素为首次从抗癌中草药鄂西香茶菜[Rabdosia henryi (Hemsl) Hara]的叶子中分离得到的二萜化合物。前人曾从毛叶香茶菜[R. japonica (Burm. f)Hara]中分离出该化合物并依据光谱数据推测其结构(右图)。但其结晶学研究尚未见报道。为研究其立体结构及分子在晶体中的排布方式,我们对该化合物的晶体进行了X射线结构分析。     

Superpositioned dielectrophoresis for enhanced trapping efficiency

One of the major applications for dielectrophoresis is selective trapping and fractionation of particles. If the surrounding medium is of low conductivity, the trapping force is high, but if the conductivity increases, the attraction decreases and may even become negative. However, high-conductivity media are essential when working with biological material such as living cells. In this paper, some basic calculations have been performed, and a model has been developed which employs both positive and negative dielectrophoresis in a channel with interdigitated electrodes. The finite element method was utilized to predict the trajectories of Escherichia coli bacteria in the superpositioned electrical fields. It is shown that a drastic improvement of trapping efficiency can be obtained in this way, when a high conductivity medium is employed.     

酶分子在试管内的定向进化及其在手性有机物合成中的应用

本文扼要介绍了当今改进酶分子性能的有效手段———分子定向进化技术的基本方法如易错PCR和DNA洗牌,以及派生的一些新技术的原理与进展,并列举了在手性有机物合成中一些成功的实例,为该领域的研究与应用提供了一些新的信息。