Application of diaza-18-crown-6-capped beta-cyclodextrin bonded silica particles as chiral stationary phases for ultrahigh pressure capillary liquid chromatography

Two bonded chiral stationary phases (CSPs), 8-aminoquinoline-2-ylmethyl- and 8-aminoquinoline-7-ylmethyl-diaza-18-crown-6-capped [3-(2-O-beta-cyclodextrin)-2-hydroxypropoxy]propylsilyl silica particles (non-porous, 1.5 microm), have been prepared and evaluated using capillary liquid chromatography at high pressures (> or = 8000 p.s.i.). High column efficiency (up to 400 000 plates m(-1)) was achieved for chiral separations. These CSPs with two recognition sites, i.e. substituted-diaza-18-crown-6 and beta-cyclodextrin combined with high chromatographic efficiency provide good resolution of a variety of enantiomers and positional isomers in relatively short times under reversed-phase conditions. After inclusion of a Ni (II) ion from the mobile phase, the positively charged crown ether-capped beta-cyclodextrin facilitates specific static, dipolar, and host-guest complexation interactions with solutes.     

轻希土硫氰酸盐与2, 3, 11, 12, -四苯基-1, 4, 7, 10, 13, 16-六氧-2, 11-十八环二烯配合物的合成及XPS研究

合成了六种轻希土硫氰酸盐与标题不饱和冠醚的新固体配合物,进行了元素分析,摩尔电导率、DTA、UV、IR和XPS等表征.对Ln(NCS)₃·L和Ln(NCS)₃的XPS研究中,得到它们组成原子芯能级电子(Ln3d_5/2,Ols,Nls,S2p)的结合能信息;观察到除Y3d_5/2外Ln3d_5/2(Ln=La、Ce、Pr、Nd、和Sm)的伴峰结构,Ln3d_5/2结合能与原子序数呈线性关系,并推断类似化合物Pm³d_5/2结合能在1035eV附近.     

圆二色谱中的激子手性法在有机化学中的应用

激子手性法是圆二色谱领域内,近一、二十年内发展的一种测定有机化合物绝对构型的可靠方法。本文对其基本原理及规律作一简要介绍。并以邻二醇、共轭烯酮,共轭二烯及丙烯醇为例,介绍本法在测定绝对构型中的应用。此外,本法也可用于糖类的结构研究。     

Single crystal tin nano-rod arrays electrodeposited by a soft template

Single crystal tin nano-rod arrays were fabricated by the electrodeposition method when amphiphilic triblock copolymer P123 was used as a soft template at a concentration much lower than that for forming a liquid crystalline phase.     

锂电池Li／KIBr2—非水体系的研究

本非水电池体系由Ｌｉ负极、多孔石墨电极和电解质溶液组成；电解质溶液由无机溶剂ＰＯＣｌ＿３（或有机溶剂硝基苯）和溶解在该溶剂中的活性物质（ＫＩＢｒ＿２）及支持电解质构成。该电池体系的开路电压为８．５０伏左右，放电性能良好，可望在实际中得到应用。此外，对电池体系的反应机理也作了初步的探讨。     

用共振电离飞行时间质谱仪分析土壤中超痕量气态金

采用激光共振电离飞行时间质谱技术（简称ＲＩＳ－ＴＯＦ技术）对土壤中超痕量气态金的含量进行了分析研究。ＲＩＳ－ＴＯＦ谱仪具有极高的灵敏度和很强的选择性，避免了对样品的预富集过程。本文给出了该谱仪对金元素的检测限和６５个土壤中气态金样品的分析结果，以及用中子活化法随机抽样检查的结果。     

铽(Ⅲ)-1,4-双(1′-苯基-3′-甲基-5′-氧代吡唑-4′-基)丁二酮-[1,4]体系荧光性质的研究及应用

本文研究了Tb(Ⅲ)-1,4-双(′-苯基-3′-甲基-5′-氧代吡唑-4′-基)丁二酮-[1,4](BPMPBD)-溴化十六烷基三甲胺(CTMAB)体系的荧光性质,探讨了响影体系荧光性质的诸因素,确定了最佳实验条件。该体系中Tb(Ⅲ)浓度以2.0×10~(-5)～1.0×10~(-10)mol/L范围内与其荧光强度呈线性关系,检测限可达到5.0×10~(-11)mol/L。应用于合成样品中微量Tb(Ⅲ)的分析,结果令人满意。     

连翘苷荧光传感器的构建和应用

以柠檬酸为碳源,三聚氰胺和甲醛为双掺杂剂合成碳量子点,并对合成的量子点进行透射电镜(TEM)、傅里叶变换红外光谱(FTIR)、X射线粉末衍射(XRD)、紫外吸收光谱(UV)和荧光光谱(RF)表征,结果表明该量子点粒径均一,发光稳定,适合用作荧光探针。优化了碳量子点含量、pH、反应时间以及温度等影响因素,结果显示检测波长λmax=425 nm时,连翘苷在0.008~0.030 mg/mL范围内有良好的线性关系,1/△f=0.00005(1/c)+0.0003(R2=0.9948),加标回收率在92.5%~106.3%之间,RSD<5%,且干扰物质、反应时间、温度等因素在一定范围内对实验结果的测定无影响。该方法可用于药剂中连翘苷含量的测定。     

Aerobic oxidation assisted by ligand-free palladium catalysts

Aerobic oxidation of electron-rich benzylic and phenyl allylic alcohols was achieved with high yields with only 0.1 mol.% of Pd(OAc)2 catalyst in the absence of any ligand. This procedure was expected to be valuable for realistic industrial-scale applications from both economic as well as environmental points of view.     

The Study of Anti-tumor Activity of Trichosanthin by Cyclic Voltammogram

IthasbeenreportedthatTrichosanthi11(TCS),isolatedfromrkiI-ilolt)ii,hasanti-tumorI-4andanti-vira1activities5-'.Someanti-tun1orremedies,whicharedesignedfromTCS,arebeingtestedanddeveloped'-.'.StudyingthebioIogicalphenomenonbyelectrochemicalmethodsisanewhotresearchspotemerginginrecentyears".Manyresultsshowedthatnotonlytheenzymesystemsuchassuccinatedehydrogenasedisplayedthediode-likebehaviorduringtheelectrontransferprocess",butalsothehigh1yorganizedorganeIle,forexample,mitochondria,andevenintac…