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31.
温和条件常温常压下 ,苯胺与CS2 在AlCl3 催化作用下反应 ,对反应混合物用乙醇进行重结晶获得白色片状晶体 ,GC/MS分析表明该晶体为异硫氰酸苯酯。然而 ,用熔点测定、HPLC/MS/MS ,FTIR ,UV和1HNMR等手段对此晶体进行分析 ,确定其为二苯硫脲。结合GC/FTIR谱图 ,研究了二苯硫脲的质谱裂解机理。实验结果表明二苯硫脲质谱裂解中可能发生了中性丢失 ,丢失了中性分子苯胺 ,生成的异硫氰酸苯酯分子离子由于π电子共轭而致稳。此机理同样能合理解释二苯脲和二萘硫脲的GC/MS谱图中只出现异氰酸苯酯和异硫氰酸萘酯分子离子峰的现象。 相似文献
32.
ICP-AES法测定盱眙野马追的微量元素 总被引:3,自引:0,他引:3
研究了用电感耦合等离子体原子发射光谱(ICP—AES)同时测定野马追全草和花蕾中微量元素的方法。采用干法和湿法消解:干法是先将样品600%高温灰化,再用浓硝酸溶解;湿法是用HNO3-HCIO4直接消解。结果表明,盱眙野马追中含有Fe、Al、Si等多种微量元素,其中Fe、Cu、Mn、Zn、Sr、Ni、Cr等是人体必需微量元素。对干法和湿法的测定结果进行了比较,得出用ICP-AES法测定野马追中的微量元素具有简单、快速、准确度高的优点。 相似文献
33.
LI Ming YAO Yi-Ming ZOU Jian-Zhong XU Zheng YOU Xiao-ZengCoordination Chemistry Institute Coordination Chemistry State Key Laboratory Nanjing University Nanjing Jiangsu China 《中国化学》1994,12(3):237-242
The synthesis spectroscopic properties and tautomerism of four novel mono-meso substituted(R)-octamethylporphyrins (R=o-hydroxybenzyl, p-aminobenzyl, 4-pyridinyl, and ferro-cenyl) were investigated. It was found that the porphyrins 2, 3 could be directly prepared in good yields via the coupling reaction of salicylaldehyde and p-aminobenzyl aldehyde with octamethyl-l',8'-dideoxy-ac-biladiene dihydrobromide, respectively. The free energy of activation (G) of the tautomerism of the porphyrins was calculated and interpreted in terms of electronic and steric nature. In contrast with 2-substituted-5,10,15,20-tetraphenylporphyrins, the substituents in meso position do not change the relative amount of two tautomers a and 6. 相似文献
34.
IntroductionTetrathiometallateanions [MS4 ]2 - (M =Mo ,W )andtheirclusterswithvarioustransitionmetalsarewell knownfortheirrichcoordinationchemistry ,1 7andtheirrelationtoindustrialcatalysisprocess ,8biologicalsystems ,9andNLOmaterials .10 12 However,thechemistryoftheorganometallictrisulfidecomplexes [PPh4 ][(η5 C5Me5) MS3](M =Mo ,13W14 )andtheirrelatedmixed metalclus tershavebeenlessinvestigated .15,16 Inordertoextendourknowledgeaboutthechemistryof [PPh4 ][(η5 C5Me5) MS3]andconti… 相似文献
35.
Binding studies of DNA with Co(Ⅲ) coordination compound 总被引:1,自引:0,他引:1
JIN Lan YANG PinStote Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu China Institute of Molecular Science Shanxi University Taiyuan Shanxi China 《中国化学》1997,(2)
The binding of Co(bpy)2dppz3+ to calf thymus DNA was investigated by using absorption and emission spectroscopy,DNA melting techniques,cyclic voltammetry,viscosity and electro-phoresis measurements,where bpy is 2,2'-bipyridyl,dppz is dipyrido[3,2-o:2',3'-c] phenazine.The binding compound shows absorption hypochromicity,fluorescence enhancement,and increasing of DNA melting temperature and the specific viscosity.CV measurement shows the shifts in oxidation-reduction potential and change in peak current with addition of DNA.The compound is also shown to be more efficient photosensitisers for strand breaks in plasmid DNA. 相似文献
36.
We give a necessary and sufficient condition for an almost Hermitian manifold to be a Kahler manifold. By making use of this condition, we give a new proof of Goldberg's theorem. 相似文献
37.
LU XiaoMei FAN QuLi ZHANG GuangWei PU KanYi & HUANG Wei Jiangsu Key Laboratory for Organic Electronics & Information Displays the Institute of Advanced Materials Nanjing University of Posts & Telecommunications Nanjing China 《中国科学:化学》2010,(5)
Water-soluble light-emitting nanoparticles were prepared from hydroxyl group functionalized oligos(p-phenyleneethynylene) (OHOPEL) and water-soluble polymers(PEG,PAA,and PG) by non-covalent bond self-assembly.Their structure and optoelectronic properties were investigated through dynamic light scattering(DLS) ,UV and PL spectroscopy.The optical properties of OHOPEL-based water-soluble nanoparticles exhibited the same properties as that found in OHOPEL films,indicating the existence of interchain-aggregation... 相似文献
38.
SANG GuangMing LUO ShiNeng LIN JianGuo QIU Ling CHEN ChuanQing YANG HaiLin & XIA YongMei Key Laboratory of Nuclear Medicine Ministry of Health Jiangsu Institute of Nuclear Medicine Wuxi China School of Chemical Material Engineering Jiangnan University Wuxi China The Key Laboratory of Industrial Biotechnology China 《中国科学:化学》2010,(5)
A facile procedure was described for the hapten design of the N-methylcarbamate insecticide propoxur.Two new haptens of propoxur(hapten 1a and hapten 1b) were synthesized by introducing appropriate spacers in the pesticide aromatic moiety of the analyte molecular structure.First,the propoxur reacted with nitric acid to yield the intermediate product.Then hapten 1a was prepared via the reduction of the intermediate product,and hapten 1b was formed by the acylation of hapten 1a with succinic anhydride.In addi... 相似文献
39.
Xiao Ming Zha Fei Ran Zhang Jia Qi Shan Yi Hua Zhang Jun O. Liu Hong Bin Sun 《中国化学快报》2010,21(9):1087-1090
<正>Solasodine 11 is a steroidal alkaloid with various biological activities.Herein,8 novel solasodine derivatives were synthesized and their effect on prostate cancer cell proliferation was assessed in vitro.Significant improvement in antiproliferative activity was achieved among some of the synthetic analogs.In particular,19 exhibited the most potent inhibitory effect against the proliferation of PC-3 cell line(IC_(50) = 3.91μmol/L). 相似文献
40.
SONG Le-Xin MENG Qing-Jin YOU Xiao-ZengCoordination Chemistry State Key Laboratory Coordination Chemistry Institute Nanjing University Nanjing Jiangsu China 《中国化学》1995,13(4):311-317
The supramolecular inclusion compound of β-cyclodextrin (β-CD, host) with (η5-cyclopentadienyl)tricarbonylmanganese [MnCp(CO)3, guest] was obtained in a crystalline state. The host-guest compound is thermally stable and do not liberate the guest on heating at 100$ in vacuum. It was characteried by elemental analysis,1H NMR, differential scanning thermal (DSC) analysis and TLC. Continueous variation plot by NMR method shows that β-CD formed 1:1 inclusion compound with MnCp(CO)3. On the basis of 1H NMR spectra and the model building with Corey Pauling Koltum (CPK) models, the most probable inclusion mode is proposed. 相似文献