壳聚糖修饰玻碳电极卷积伏安法测定环境水中的EDTA

制备了壳聚糖修饰玻碳电极 ,研究了Fe(EDTA) -在修饰电极上的吸附还原行为 ,用卷积伏安法通过Fe(EDTA) -的检测测定了环境水中的EDTA。在优化的实验条件下 ,峰电流值与 8.0× 1 0 -7～ 5 .0× 1 0 -6mol L的EDTA呈线性关系 ,回归方程为epp′ =0 .75 2 5c - 0 .661 3,r =0 .991 ,最低检出限为 5 .0× 1 0 -7mol L ,5次测定的相对标准偏差小于 5 .8%。对实际样品测定的回收率为98 1 %～ 1 0 5 % ,对比HPLC的结果 ,相对偏差小于 5 %。     

Agonist–PPARγ interactions: Molecular modeling study with docking approach

Docking simulation of 18 agonists with the ligand binding pocket (LBP) of PPARγ has been performed. The binding conformations and binding affinities of these agonists were obtained by use of the flexible docking protocol FlexX. Test compound calculations indicated that FlexX can reproduce the binding conformation of the crystal structure (root mean square deviation = 1.43 Å); moreover, the predicted binding affinities correlate well with the activities of these agonists. The interaction model and pharmacophore of PPARγ agonists were derived and the difference in biologic activities of these agonists can be well explained. The PPARγ agonists must have both polar head and the hydrophobic tail, which form hydrogen bonds and hydrophobic contacts with hydrophilic and hydrophobic regions of the LBP of PPARγ, respectively. In addition, a suitable linker is also necessary. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 93: 405–410, 2003     

用SbCl_3使聚丙烯腈纤维稳定化的研究

<正> 众所皆知,梯型高分子是相当耐热的,其中一大部分是耐燃的梯型高分子。制造梯型高分子的方法很多,它可以通过小分子的有机化合物,经缩合或用大分子中的功能基反应得到梯型高分子。聚丙烯腈(PAN)中有大量的腈基,通过聚合而得到含聚氢化吡啶并经得起950℃的耐热梯型高分子。     

Synthesis, structural characterization and ferrimagnetic property of MnPS3 intercalated with nickel(II) cyclopolyamine complex cations

Two new intercalation compounds were prepared by the reactions of Ni(II) cyclopolyamine complex cations with a preintercalate Mn_1−xPS₃K_2x(H₂O)_y, respectively, through “ion exchange” process. Their structures were characterized by elemental analysis, X-ray powder diffraction and infrared spectroscopy. The lattice spacing increased 0.567 and 1.093 nm with respect to the pristine MnPS₃. Ferrimagnetism of the intercalates was confirmed by SQUID experiment with T_c at 40 and 33 K, respectively.     

金橙G螯合形成树脂分离富集地质样品中的微量贵金属

主要研究了金橙Ｇ螯合形成树脂分离富集地质样品中金、铂、钯的最佳实验条件。在柱高大于１６ｃｍ，０．１ｍｏｌ／Ｌ ＨＣｌ介质的样品溶液以小于或等于０．５ｍＬ／ｍｉｎ流速过柱，用０．１ｍｏｌ／Ｌ ＨＣｌ的３％硫脲溶液以小于或等于０．５ｍＬ／ｍｉｎ流速洗脱金、铂、钯（和铑），都能同时定量富集。用火焰原子吸收光谱法测定，回收率均在９５％￣１１０％之间。经地质样品加标准回收实验，结果令人满意。证明这种以磺酸基     

A New Kind of Void Soap-free P（MMA-EA-MAA） Latex Particles

Soap-flee P(MMA-EA-MAA) particles with narrow size distribution were synthesized by seeded emulsion polymerization of methyl methacrylate (MMA), ethyl acrylate (EA) and methacrylic acid (MAA), and large voids inside the particles were generated by alkali posttreatment in the presence of 2-butanone. Results indicated that the size of void and theparticle volume were related with the amount of 2-butanone. The generation mechanism of voids was proposed.     

丙烯酸酯和甲基丙烯酸酯基团转移共聚研究

研究了三种丙烯酸酯分别和四种甲基丙烯酸酯的基团转移共聚，用１Ｈ ＮＭＲ法测定共聚物组成，扩展的Ｋｅｌｅｎ Ｔｕｄｏｓ法测定竞聚率，结果为γＭＡ＝９２３、γＭＭＡ＝００６；γＥＡ＝１４１５、γＭＭＡ＝００１；γＢＡ＝７５１、γＭＭＡ＝００２；γＭＡ＝１４４１、γＥＭＡ＝００１；γＭＡ＝１３９６、γＢＭＡ＝０２３；γＭＡ＝８６６、γｉ ＢＭＡ＝００８，表明基团转移聚合同阴离子聚合有明显的相似之处．     

3，9－二羟乙基－3＇，9＇－二苯甲基－1，5，7，11－四氧杂螺环［5，5］十一烷的合成和聚合反应

从两二酸二乙酯、氯乙酸乙酯和氯苄出发，经ＬｉＡｌＨ４还原，合成新的二元醇，进而合成新的螺环化合物：３，９－二羟乙基－３＇，９＇－二苯甲基－１，５，７，１１－四氧杂螺［５，５］十一烷．该化合物的结构由它的氢和碳－１３核磁共振谱、红外光谱和元素分析得到证明．该单体在三氟化硼乙醚络合物的作用下进行开环聚合反应．由于环上四个取代基的稳定作用，聚合物的收率比较低（产率１０％左右）．通过对聚合物的结构分析，提出了这一单体的阳离子开环聚合反应机理．对随聚合温度升高，聚合物中酯基／苯基的克分子比降低，以及本体聚合时得到交联聚合物等一系列现象作了探讨．     

反应原料组成对单分散苯乙烯微球粒径及其分布的影响

采用分散聚合工艺制备微米级单分散聚苯乙烯微球，并对分散聚合反应的内部影响因素(分散稳定剂、助稳定剂、单体、引发剂)进行了研究．结果表明，随着分散稳定剂和助稳定剂用量的增加，聚苯乙烯微球的粒径减小；随着单体和引发剂用量的增加，聚苯乙烯微球的粒径增大．分散稳定剂和单体用量是影响聚苯乙烯微球粒径分布的两个主要内部因素．     

CVD Reactions of TiCl4 with Ammonia： a Quantum Chemical Study

Based on density functional calculations, the mechanism and the energetic course of the chemical vapor deposition （CVD） reaction of TiCl4 with NH3 were studied at the level of B3LYP with 6-311g（d） basis set. Furthermore, the polymerization processes of dimerization, trimerization and tetramerization were investigated. The calculation results indicate that the formation of polymers is favored at the elimination reaction. On the basis of the calculated energetics, a possible mechanism of the reduction reaction has been proposed.