(CH3)2N(C6H4)nCN系列分子二阶非线性光学系数的理论研究

在AM1和INDO/CI方法的基础上, 用自编程序计算了(CH3)2N(C6H4)nCN(n=1→6)系列分子的二阶非线性光学系数β~i~j~k和β~μ并系统地研究了共轭链长对分子二阶非线性光学系统的影响及β~μ对激光场频率的依赖关系(色散效应)     

PVC DISULFIDE AS CATHODE MATERIALS FOR SECONDARY LITHIUM BATTERIES

PVC disulfide (2SPVC) was synthesized by solution crosslink and its molecular structure was confirmed by infrared spectrum. 2SPVC's specific area is 36.1 m2·g-1 tested by stand BET method, and granularity experiment gives out the particle size of d0.5= 11.3μm. With SEM (Scanning Electron Microscope) experiment the surface morphology and particle shape of 2SPVC were observed. Cyclic voltammetry (scan rate: 0.5 mV·s-1) shows that 2SPVC experience an obvious S-S redox reaction in charge-discharge process. When 2SPVC was used as cathode material for secondary lithium battery in a 1 mol·L-1 solution of lithium bis(trifluoromethylsulfonyl) imide (Li(CF3SO2)2N) in a 5:45:50 volume ratio mixture of o-xylene (oxy), diglyme (DG) and dimethoxymethane (DME) at 30℃, the first discharge capacity of 2SPVC is about 400.3 mAh·g-1 which is very close to its theoretical value (410.5 mAh·g-1) at a constant discharge current of 15 mA·g-1. It can retain at about 346.1 mAh·g-1 of discharge capacity after 30 charge-discharge cycles. So 2SPVC is a very promising cathode candidate for rechargeable lithium batteries.     

△,Λ-[Co(phen)2tpphz]^3+与B - DNA相互作用的分子 模拟

针对国际上对金属配合物同DNA间作用机量的争议,采用分子模拟手段在MM2力场下,搭建并优化了手性金属配合物△,Λ-[Co(phen)2tpphz]^3+与B-DNA[d(GTCGATCGAC)2]的模型,继而对其相互作用进行了模拟,得出的结论是：对所采用的B-DNA片断,该金属配合物有明显的立体选择性△型配合物从小沟插入占明显优势,而且,总体来看,从AT区插入更易进行。     

多氟芳烃的亲核反应I.仲胺作为亲核试剂

本文报道全氟苯、一氯五氟苯和二氯四氟苯与仲胺在DMF或HMPA中的亲核反应结果,C6F5Cl与仲胺反应生成对位产物,C6F4Cl2(m:o:p)=73:18:9)与仲胺的反应,只有m-和o-异构体能生成预期产物,而p-C6F4Cl2只与活性高的四氢吡咯反应,延长反应时间和提高反应温度,C6F6可给出对双取代产物,六个仲胺的反应活性顺序是:四氢吡咯>哌啶>吗啡啉>二乙胺>二正丙胺>二异丙胺。     

Schiff碱型和仲胺型双冠醚II: 用双冠醚作载体的PVC膜钾离子选择性电极

用六个含二个苯并-15-冠-5单元的席夫碱型和仲胺型新型双冠醚作载体制备了钾离子选择性PVC膜电极,并研究了它们的电极行为,这些电极对所有的其它碱金属和碱土金属离子展现出显著的钾离子选择性,可期望有一定的应用价值.     

用α－苯乙胺拆分制备高光学活性线性二级醇

用手性α-苯乙胺作为拆分剂以较好的收率拆分了具有线性结构的二级醇，1－ 对烷基苯基取代的乙醇和α－苯丙醇，光学纯度达92％－98％。并初步研究了二级 醇结构对拆分的影响。     

INFLUENCE OF MOLECULAR STRUCTURES OF SECONDARY AMINE TERMINATED POLY（ESTER-AMINE）S ON THE CURING PERFORMANCE WITH EPOXY RESIN

Five secondary amine terminated poly(ester-amine)s(defined as PEA)with controlled molecular structures were synthesized through reacting excessive piperazine with phthalicdiglycol diacrylate(PDDA)and 1,1,1-trimethylolpropane triacrylate(TMPTA)at a constant secondary amine/acrylate group ratio of 1.5/1 and at different PDDA/TMPTA molar ratios. Both IR and ~(?)H-NMR spectra indicated that all acrylate groups were consumed in the reaction,based on which the structural parameters were calculated from the ~(?)H-NMR spectra.With decreasing PDDA/TMPTA ratio,the content of secondary amine,degree of branching,molecular weight,T_g and T_d increased accordingly.These polymers were further used as both crosslinkers and flexibilizers for a linear epoxy resin E51 to form cured films under ambient condition.The gel content, relative hardness and T_g of the resulting films increased as PEA molecules changed from linear to highly branching structures.Due to the flexibility of PEA molecules,all the films possessed excellent mechanical performance.     

Photochemical studies with a zeolite Y membrane formed via secondary growth

Zeolite membranes offer an attractive feature in design of artificial photosynthetic assemblies because they can keep the charge separated species apart, yet allow for communication between the two sides via the intervening zeolite channels and cages. However, such a strategy would require that the zeolite membrane be pinhole-free. In an earlier paper (J. Phys. Chem. B 106, 11898 (2002)), we have shown that nanocrystalline zeolite Y can be spin-coated on porous substrates to form membranes, and the pinholes can be plugged by a photoresist. Such membranes do not allow manipulation at higher temperatures or even in solution chemistry because of the thermal instability and solubility characteristics of the photoresist. In this paper, we report on a zeolite Y membrane made by the secondary growth method. The growth process leads to minimal pinholes as determined by leak tests. The sturdiness of the membranes allows for manipulation and we have shown that organic reactions can be carried out in the zeolite pores. Charge transport through the membrane by an electron hopping process mediated via self-exchange of ion-exchanged bipyridinium ions are demonstrated. The electron transfer was initiated using a photochemical Ru(bpy)²⁺₃-EDTA system.     

次级化学平衡反相高效液相色谱法分离银杏酚酸

采用LC/(-)ESI-MS法对银杏叶中的致敏性成分银杏酚酸进行了鉴定。利用次级化学平衡理论,建立了银杏酚酸的反相银化高效液相色谱分离方法。从色谱热力学角度对银离子分离银杏酚酸的影响进行了考察。在流动相中添加银离子,降低了具不饱和侧链银杏酚酸的保留时间,且银离子浓度与容量因子的对数之间存在良好线性关系。在确定的色谱条件下,四种银杏酚酸均获得较高的分离度,表明反相银化液相色谱是分离碳数与饱和度不相同的银杏酚酸同系物的有效方法。