螯合物离子色谱

螯合物离子色谱是一种利用螯合物进行不同方式分离和检测的离子色谱模式，目前已经被痕量金属分析广泛采用，本文对一些螯合物阳离子交换色谱、螯合物色谱、阴离子交换色谱和离子对色谱最新进展进行了综述，并采用基本螯合物化学理论（金属螯合物稳定性、金属原子有效电荷、螯合剂能力等）对保留和分离机理进行了讨论。     

光色谱及其进展

本文评述了光色谱的产生，特点和分离原理，对影响光色谱分离的主要因素进行了讨论，并提出了光色谱今后的发展方向和应用前景。     

毛细管电色谱研究进展

毛细管电色谱是一种新兴的具有高效，高选择性的微分离技术。本文评述了毛细管电色说的发展状况和相关的技术，并对其发展前景进行了展望，引用文献２４篇 。     

亲和膜色谱

亲和膜色谱又称亲和膜分离，其在蛋白质的分离纯化中作为一种综合性的技术出现在80年代末。亲和膜色谱主要优点是克服了颗粒状多孔载体扩散传质阻力大的缺点，代之以对流传质，这样就可以在较低的操作压和较高的流速下对目标蛋白进行快速的分离和纯化，从而缩短操作时间、提高纯化效率。本文将就近年来亲和膜色谱及其在蛋白质分离和纯化中的应用作一综述性介绍。     

氨基酸手性色谱分离

光学活性和立体构象不同的氨基酸，具有不同的生理活性和作用，因此，实现氨基酸的有效手性分离具有重要意义。色谱法是常用的氨基酸手性分离方法，具有分离效率高、速度快、灵敏、成本低和绿色环保等特点，在氨基酸手性分离和检测领域应用广泛。本文综述了色谱法在氨基酸手性分离方面的最新进展，并对其发展趋势进行了展望。     

填充毛细管液相色谱-毛细管气相色谱在线联用技术

建立了一套填充毛细管液相色谱－毛细管气相色谱在线联用的二维色谱分离体系。联用接口由十通阀和多位阀构成，将经填充毛细管液相色谱分离后的样品各馏分在线准确切割和储存，并在线无损失输送至ＧＣ分析，从而实现了复杂样品的一次进样全组分的分离分析。     

烟碱的色谱测定

总结了近十多年来色谱法(GC、GC-MS、HPLC和SFC等)测定烟碱的情况，归纳整理了国内外主要杂志报道的有关色谱分析烟草、卷烟及其烟气、空气、农药、鼠脑、唾液、头发、血液、尿等中烟碱的方法，并对色谱分析烟碱的主要方法及其发展前景进行了评述。     

多柱色谱技术进展

在色谱分析过程中，利用串联、并联或串并联结合的方式将多根色谱柱组合起来，可以实现高通量和高分辨的分离效果。相比于传统单柱色谱技术，多柱技术很好地满足了批量样品分析和复杂生物样品分离分析的需求，因此引起了广泛关注。该文对多柱技术在多维分离、芯片色谱、毛细管电泳、固定相筛选以及串联色谱等领域的应用进行了综述，并对其发展前景进行了展望。     

由液相色谱保留值变化规律式推荐液相色谱分离模式的研究

 提出了液相色谱柱系统选择的二个基本条件，在此基础上应用统计热力学导出保留值当变化规律式，建立了符合色谱柱系统选择条件的液相色谱分离模式的推荐规则，并利用色谱专家系统中液相色谱谱图库的110张谱图，对该分离模式的推荐规则进行了初步验证，结果表明二者能较好地相符。     

气相色谱固定相研究进展

介绍了气相色谱固定相的研究进展，重点对各种冠醚固定相的特征，应用和分离机理进行了评述。     

线状铜电极在磷酸溶液中电流混沌振荡的同步行为

研究了恒电位下两个铜线电极在磷酸溶液中的电流混沌振荡行为,通过恒定不同的电位数值,改变单个电极的电流振荡混沌行为,研究了不同混沌间的相互作用.调整线电极间的距离,研究了电极间距对电流振荡行为的影响.实验中两电极的振荡间呈现了复杂的耦合作用,耦合后的频率与耦合前电极原有的频率不同.两电极的混沌电流振荡中呈现出同步、准周期同步和反相同步等现象.电极距离一定时,振荡波形差别很大的两电极的电流容易呈现反相同步和准周期同步,波形差别不大时容易产生同步.强的耦合导致电极间电流振荡的同步,电极距离的加大,电极间电流振荡难以产生同步.对耦合作用机制也进行了探讨.     

超声波-微波法制备NiW/Al2O3加氢脱硫催化剂

 采用一次浸渍技术制备了NiW/Al2O3加氢脱硫(HDS)催化剂,在制备过程中采用超声波处理浸渍液,采用微波进行样品干燥. 以噻吩为模型化合物,在微反装置上评价了该催化剂的加氢脱硫活性. 使用X射线光电子能谱和透射电镜等表征手段研究了催化剂的表面状态和物化性. 结果表明,使用超声波及微波技术制备的NiW/Al2O3催化剂具有较高的加氢脱硫活性,催化剂的活性组分较易硫化,可生成更多的硫化物种参与反应. 催化剂中硫化态钨的表面原子浓度较高,从而使硫化态钨物种保持较高的表面分散度,有利于增加活性中心的数目. 该催化剂的活性中心结构具有较多配位不饱和的边缘位和棱边位,因而具有较高的加氢脱硫活性.     

锌试剂与壳聚糖的结合反应机理的研究

为从分子水平认识多糖分子与小分子之间相互作用的机理,应用光谱法研究了壳聚糖(CTS)与锌试剂(ZCN)的相互作用机理;测得ZCN-CTS复合物吸收光谱出现新的吸收峰所需的临界ZCN/CTS摩尔比为2.67×103, CTS对ZCN的最大结合数为6.93×103,实验值与理论值相吻合,证明了多糖与生物探针相互作用理论模型的可靠性;探讨了ZCN与CTS相互作用产生变色反应的机理,认为其是在ZCN与CTS大分子间发生静电相互作用的基础上,主要由ZCN与CTS大分子间的疏水相互作用所引起.     

煤中矿物质及其燃烧后的变化分析

以淮北煤田6煤层煤为样品，采用中子活化法、化学方法、X射线衍射及扫描电镜等方法对煤及其灰样品中的矿物质、微量元素进行了分析，在此基础上，研究了样品中主要矿物的种类及其形成时的影响因素，分析了它们在燃烧前后的主要变化。通过分析可知，样品中主要含有高岭石、石英、方解石和黄铁矿以及多种微量元素；在燃烧过程中，微量元素的含量以及矿物的种类发生了变化，并形成高温稳定的矿物种类。     

Synthesis,analytical characterization and bioactivity of Ag and Cu nanoparticles embedded in poly-vinyl-methyl-ketone films

The electrosynthesis of copper and silver core-shell nanoparticles (NPs) by the sacrificial anode technique, employing tetraoctylammonium (TOA) salts as base electrolyte for the first time, is described. These surfactants were selected because they combine high NP stabilizing power with useful disinfecting properties. The resulting colloids were mixed with a solution of an inert dispersing polymer and used to prepare nanostructured composite thin films. The morphologies and chemical compositions of the nanomaterials were characterized by Transmission Electron Microscopy (TEM) and X-ray Photoelectron Spectroscopy (XPS). The TEM reveals that the average core diameter of the metal NPs ranges between 1.7 and 6.3 nm, as a function of the nature of the metal and of the electrosynthesis conditions, and does not change significantly upon inclusion in the polymer matrix. An appreciable concentration of the metal is detected on the nanoparticle surface by XPS. High-resolution XP spectra indicate that both copper and silver are present at zero oxidation state in all of the materials (colloids and composite films). This demonstrates the high efficiency of the surfactant at controlling the morphology and the chemical composition of the nanodispersed metal in both the as-synthesized colloid and in the polymeric dispersion. The nanocoatings are shown to exert a marked inhibitory effect on the growth of eukaryote and prokaryote target microrganisms, and experimental evidence of a synergic disinfecting effect due to the surfactant and the nanodispersed metal is provided. On the basis of these stability and bioactivity results, it is clear that Cu-NPs and Ag-NPs are suitable for application in disinfecting or antifouling paint and coating formulations.Electronic Supplementary Material Supplementary material is available for this article at Dedicated to the memory of Wilhelm Fresenius     

Contributions to the Chemistry of the Binary Compounds of the Transition Elements

Phase and structural relationships of the sulfur, selenium, and tellurium compounds of the 4d and 5d transition elements of groups IV to VII of the periodic system are discussed. Homologous elements behave very similarly with respect to the chalcogens, and this is particularly the case for niobium and tantalum, and for molybdenum and tungsten. However, zirconium, niobium, and molybdenum have a greater tendency towards formation of chalcogen-poor phases than their homologues hafnium, tantalum, and tungsten. Subchalcogenides are known only for zirconium and niobium. The number of phases and the tendency towards formation of solid solutions are considerably smaller among the tellurides than among the sulfides and selenides. The crystal structures of the telluride phases also differ from those of the sulfide and selenide phases of analogous composition. In addition, a review of the phase and structural relationships of the arsenic and antimony compounds of the 4d and 5d transition elements of groups V to VII is given.     

Determination of neutral and cationic herbicides in water by micellar electrokinetic capillary chromatography

The separation and determination of two s-triazines and two quats in water samples by MEKC was described. The influence of pH, type and concentration of buffer, concentration and type of surfactant, organic modifier and the added salt on the separation of the two neutral and the two cationic herbicides was studied. Simazine and atrazine (neutral compounds at the working pH) were little influenced by the chemical variables, while the cationic paraquat and diquat were more influenced. In the optimisation on the separation voltage, the total concentration of salt in the run buffer and the repeatability of the separation were taken into consideration. The composition of dissolution, in which the analytes were dissolved, was also studied.A solid-phase extraction method to retain and to elute the four analytes in a single step was also developed. Recoveries between 80 and 95% and R.S.D. between 6 and 10% was obtained in the analysis of a well-water sample spiked with 2 and 5 ppb of triazines and quats, respectively. Detection limits were between 0.6 and 1.9 ppb.     

LOW DENSITY POLYETHYLENE/CLAY NANOCOMPOSITES MODIFIED BY ETHYLENE COPOLYMERS： EFFECTS OF FUNCTIONALIZED SEGMENTS ON MORPHOLOGY

Melt extrusion was used to prepare binary nanocomposites of ethylene copolymers and organoclay and trinary nanocomposites of low-density polyethylene （LDPE）, ethylene copolymer and organoclay. X-ray diffraction （XRD） and transmission electron microscopy （TEM） were used to analyze the structure of the clay phase and the morphology of the nanocomposites. Influences of the comonomer in the copolymer and the content of the copolymer on the morphology of the resulting nanocomposites were discussed. The binary and the trinary composites may form intercalated or exfoliated structures depending on the interaction between the copolymer and the clay layers and the content of the copolymer.     

载体对包埋酶微环境的影响分析

包埋法固定化酶过程中,酶固定化载体的选择和设计是酶固定化过程的关键因素,适宜的载体微环境对酶活性和稳定性的影响尤为重要。论文首先分析并提出了影响固定化酶所处载体微环境的主要因素,包括载体的亲疏水性、结构形态和反应活性。载体的亲疏水性决定固定化酶微环境中的水分含量。载体的结构形态对酶形成的笼效应,以及载体的反应活性,包括共价键合、静电和氢键等的结合能力,影响酶构象的稳定性和运动性。另外,底物／产物的扩散速率和酶的可及性也同样受到载体的孔结构、孔分布以及载体反应活性的影响。本文介绍了常用的酶包埋载体,包括sol-gel二氧化硅、高分子水凝胶以及高分子－二氧化硅杂化凝胶固定化酶过程,结合上述影响酶微环境的因素,分析比较了三类载体固定化酶的包埋率、活性和稳定性,综述了为改善固定化酶微环境所进行改进研究的进展。     

Ga、Zn改性方法对HZSM-5催化剂丙烯芳构化性能的影响

以浸渍法和水热合成法对ZSM-5分子筛进行Ga、Zn改性,制得不同酸性的分子筛催化剂。采用XRD、SEM、NH3-TPD和XPS等表征手段,研究考察了Ga、Zn和不同引入方法对催化剂的孔结构、骨架结构特性和表面酸性的影响,并以丙烯芳构化为模型反应,考察了Ga、Zn改性对ZSM-5催化剂烯烃芳构化催化性能的影响。研究结果表明,Ga、Zn改性对催化剂形貌影响较小,但能明显改变催化剂的表面酸性和烯烃芳构化性能。Zn改性能降低催化剂的酸性,而Ga改性与其引入的方式有关,浸渍法引入催化剂的中强酸位略有下降,而水热合成法引入则显著增加了催化剂的总酸量。Ga、Zn改性均提高了芳构化反应的活性和芳烃选择性,并抑制催化剂表面积炭。