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751.
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Wen‐Sheng Zhang Wen‐Jing Xu Fei Zhang Yu‐Zhe Wang Jun Li Bao‐An Wang Yan Li 《中国化学会会志》2012,59(6):753-757
3‐Ferrocenyl acrylic acid, synthesized from ferrocenecarboxaldehyde and propandioic acid in water‐insoluble ionic liquid (1‐butyl‐3‐methylimidazolium hexafluorophosphate, [BMIM]PF6) at 85 °C in high yield, was transformed to a series of 3‐ferrocenyl acrylate of alcohols and phenols in water‐soluble ionic liquid (1,3‐dimethylimidazolium dimethylphosphate, [DMIM]Me2PO4) at room temperature in the presence of dicyclohexylcarbodiimide (DCC) and 4‐dimethylaminopyridine (DMAP). 相似文献
754.
Novel lanthanide coordination compounds with ciprofloxacin (CPFX), including eleven complexes Ln(CPFX)2Cl(H2O), (Ln=Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb; n = 7, 8, 9) and crystalline [Ce(CPFX)2 (H2O)4] Cl (H2O)3.25 (C2H5‐OH)0.25, were synthesized. The crystal is of triclinic space group Pi with a= 1.3865(2) nm, b = 1.3899(3) nm, c = 1.6505(2) nm, a = 92.73(1)°, β= 114.39(1)°, γ=115.55 (1)°, Z = 2 and R = 0.0449. FT‐IR, electronic spectroscopy and X‐ray diffraction were employed to show that the lanthanide ion, which displays an eight‐coordinate structure, is chelated by 3‐carboxyl and 4‐keto oxygen donors of CPFX and two six‐membered chelate rings are formed. Test of in vitro antibacterial activity against E. coli, P. aeruginosa and S. aureus indicated that the in vitro antibacterial activity of the ligand can be improved by complexation with Ce(III). 相似文献
755.
Direct electrochemistry of redox proteins can provide a good model for the studies of redox process in biological system Electron transfer between redox metalloproteins and underlying electrodes was greatly enhanced in lamillar liquid crystal surfactant films compared to that on bare electrodes with the puoteins in solution1,because these filmsprovide a favorable biomebrane-like micuoencironment for the puwtins2 Orderedsurfactant-clay composite films in which anionic clay platelet layers sandw… 相似文献
756.
Introducing various pendant functional groups and building blocks of interest to polypeptides in a highly efficient, controlled manner is crucial to access polypeptide materials with desired structures and functions. In this study, we synthesized γ-(4-vinylbenzyl)-(L)-glutamate N-carboxyanhydride (VB-Glu-NCA), which was readily obtained and purified in large quantity. VB-Glu-NCA monomer was subsequently used for the synthesis of polypeptides containing conjugation-amenable, pendant vinyl functional groups. Controlled, living polymerizations of VB-Glu-NCA were achieved by using hexamethyldisilazane (HMDS) as the initiator, catalytic amounts of 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as the co-catalyst, and nitrobenzene as the inhibitor of radical-induced side reactions on the vinyl group of VB-Glu-NCA. The resulting poly(γ-(4-vinylbenzyl)-(L)-glutamate) (PVBLG) gave rise to polypeptides containing pendant functional groups or moieties through various vinyl chemistries. 相似文献
757.
Ye Liu Fei Qin Fei Zhou Qing-bo Meng Dao-zhong Zhang Zhi-yuan Li 《Frontiers of Physics in China》2010,5(3):220-244
Nonlinear photonic crystals made from polystyrene materials that have Kerr nonlinearity can exhibit ultrafast optical switching
when the samples are pumped by ultrashort optical pulses with high intensity due to the change of the refractive index of
polystyrene and subsequent shift of the band gap edge or defect state resonant frequency. Polystyrene has a large Kerr nonlinear
susceptibility and almost instantaneous response to pump light, making it suitable for the realization of ultrafast optical
switching with a response time as short as a few femtoseconds. In this paper, we review our experimental progress on the continual
improvement of all-optical switching speed in two-dimensional and three-dimensional polystyrene nonlinear photonic crystals
in the past years. Several relevant issues are discussed and analyzed, including different mechanisms for all-optical switching,
preparation of nonlinear photonic crystal samples by means of microfabrication and self-assembly techniques, characterization
of optical switching performance by means of femtosecond pump-probe technique, and different ways to lower the pump power
of optical switching to facilitate practical applications in optical information processing. Finally, a brief summary and
a perspective of future work are provided. 相似文献
758.
Fei Gao Bian‐Hong Meng Yi‐Bin Wei 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):m360-m362
The crystal structure of the title compound, [Mg(H2O)6]0.5[Mg2(C16H14ClN2O9)(H2O)4]·10H2O, shows that this binuclear complex consists of two Mg centres in distorted octahedral geometry, joined by an oxo bridge which is a derivative of the deprotoned hydroxy group of the phenolate in the ligand molecule. In the anion, the coordination sphere of each MgII ion is completed by two carboxylates, a tertiary N atom and two water molecules. The inner coordination spheres for the MgII ions are very similar, both in ligand sets and in geometry. Each unit of the binuclear complex has one negative charge neutralized by a neighbouring hydrated cation, [Mg(H2O)6]2+, in which the Mg atom lies on an inversion centre. In each cell, there are 34 water molecules and most of them participate in the formation of hydrogen bonds, which contribute greatly to the stability of the whole structure. 相似文献
759.
760.
Hong‐Lin Zhang Zhe Kong Yong‐Mei Yan Li Yu Fei Geng 《Journal of Dispersion Science and Technology》2013,34(6):958-964
The critical micelle concentration (CMC) of two kinds of anionic surfactant (including sodium laurate (SLA) and sodium dodecyl sulfate (SDS)) in mixed alcohol and N, N‐dimethyl formamide solvent (DMF) were investigated through measuring power‐time curves by titration microcalorimetry. From data of the lowest point and the area of the power‐time curves, their CMC and ΔH m 0 can be obtained. According to standard thermodynamic equations, ΔG m 0 and ΔS m 0 also can be calculated. For different surfactant, the influences of the carbon number and the concentration of alcohol on the CMC and standard thermodynamic functions are different in DMF polar medium. These thermodynamic functions for micelle formation can be further interpreted. 相似文献