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171.
Li Jiang Fushen Lu Qing Chang Yang Liu Huibiao Liu Yuliang Li Wei Xu Guanglei Cui Junpeng Zhuang Xiaofang Li Shu Wang Yinglin Song Daoben Zhu 《Chemphyschem》2005,6(3):481-486
An ultrathin composite film containing anionic Ag-His complexes (His: L-Histidine) and oppositely charged BH-PPV was fabricated by means of the electrostatic layer-by-layer self-assembly technique. UV/Vis spectra showed a continuous deposition process of Ag-His complexes and BH-PPV. The film structure was characterized by using small-angle X-ray diffraction, AFM, and SEM. The nonlinear optical properties of the ultrathin film were studied by using the Z-scan technique with a laser duration of 8 ns at a wavelength of 532 nm. The film sample exhibited a strong nonlinear saturated absorption, with an alpha2 value of -3.9 x 10(-5) mW(-1) and a self-defocusing effect with an n2 value of -4.78 x 10 (-12) m2W(-1). 相似文献
172.
173.
174.
Ying Wang Pu Xiao Gang Qiang Wu Su Qing Shi Jun Nie 《中国化学快报》2007,18(8):977-980
A benzophenone derivative photoinitiator, HBP-TDI-HQ-TDI-HBP (HTCTH), was synthesized based on 4-hydroxy benzophenone (HBP), toluene-2,4-diisocyanate (TDI) and hydroquinone (HQ). HTCTH was a more effective photoinitiator which had longer wavelength absorption in the UV-vis absorption spectra than the low molecular counterpart benzophenone (BP). It showed that both rate of polymerization (Rp) and final conversion (P) increased with increase of amine and HTCTH concentration in photopolymerization. 相似文献
175.
A series of pyrazolo[3,4‐b]pyridines was synthesized by the reaction of 5‐aminopyrazole with benzylidenemalononitrile in aqueous media. The structures were characterized by IR, 1H NMR, and elemental analysis and were further confirmed by X‐ray diffraction analysis. 相似文献
176.
177.
A novel bridged β-CD dimer in which two β-cyclodextrins were linked by a naphthalene at positions 2 and 7 has been synthesized. 1H and 13CNMR measurements showed that a large change in the conformation of the dimer occurred in aqueous solution. The dimer interacted with methyl and ethyl orange to form stable inclusion complexes via "induced fit" mechanism. 相似文献
178.
1,1,3,3-Tetraorganodistannoxanes [XR2SnOSnR2X]2 (R = alkyl, Ph; X = halogen, NCS, OAc, OR) are a kind of organotin oxo clusters. They have received considerable attention because they are useful catalysts for many reactions1-5. And recently S. W. Ng reported that [XR2SnOSnR2X]2 (R = Bu, X = OOCCH2SC(O)N(CH2CH2)2O) had more active antitumor activity than cis-platin in vitro6. A characteristic feature of symmetric tetraorganodistannoxanes in the solid state is their dimeriz… 相似文献
179.
180.
Simultaneous analysis of oxidized and reduced glutathione in cell extracts by capillary zone electrophoresis 总被引:1,自引:0,他引:1
Yang Q Krautmacher C Schilling D Pittelkow MR Naylor S 《Biomedical chromatography : BMC》2002,16(3):224-228
Glutathione (GSH) and glutathione disulfide (GSSG) levels in cells constitute a thiol redox system. They can be used as an indicator of oxidative stress of the cell. In this study, a capillary zone electrophoresis (CZE) method is described that enables quantitation of GSH and GSSG from cellular extracts. The CZE buffer used was 20 mM ammonium acetate containing 5% (v/v) acetic acid at pH 3.1 in conjunction with a polybrene coated capillary operated in reverse polarity mode. Effects of different acids used to prepare cell samples were investigated on CZE performance. The acids include meta phosphoric acid (MPA), trichloroacetic acid (TCA), phosphoric acid (PA) and sulfosalicylic acid (SSA) and are used to stabilize GSH and GSSG before performing CZE analysis. The method features a limit of detection of 4 microM and a limit of quantitation of 12 microM for both GSSG and GSH and recoveries of 94% for GSH and 100% for GSSG. Quantitative analysis of GSSG and GSH in HaCaT cell extracts (5% SSA, w/v) was performed with this method and changes in the ratio of GSH to GSSG in N-ethylmaleimide treated cell sample was observed by comparing with control cell samples. 相似文献