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191.
192.
醋酸铅(Pb(Ac)2·3H2O)和咪唑乙酸(Hima)通过溶胶凝胶扩散合成二维配位聚合物[Pb(ima)2]n(1)的单晶。X-射线单晶衍射分析表明,晶体属于单斜晶系,P21/n空间群,晶胞参数为:a=0.8750(2)nm,b=5.1226(12)nm,c=13.292(3)nm,β=93.570(4)°,V=594.6(2)nm3,Z=2。配合物[Pb(ima)2]n是一个具有二维kgd拓扑结构的配位聚合物,二维层间又通过C-H…O氢键连接形成三维超分子结构。对配合物的红外、元素、热重及荧光等性质进行了研究。 相似文献
193.
The title compound,[Ag(L)]·H2O,1,where HL=4-(isonicotinamido)benzoic acid,was synthesized in methanol solution and its crystal structure was determined by X-ray diffraction analysis.The crystal is of monoclinic.space group P21/c with a=0.571 8(8)nm,b=1.357 2(18)nm,c=1.5580(2)nm,β=91.090(2)°,V=1.2090(3)nm3,Z=4,Dc=2.009 g·cm-3,F(000)=722,Rint=0.042 9,R=0.027 1,wR=0.055 6.In complex 1,the Ag atoms are linearly coordinated by one O atom and one N atom of two ligand molecules.Each I- ligand in turn uses its one carboxylate group and one pyridinyl groups to connect two metal centers,then the one-dimensional (1D) chains is formed.On the other hand,the 1D chains are further connected by O1W-H1WB…O2 hydrogen bonds and Ag-O weak interactions to give a two-dimensional (2D) layer,finally,the 2D net extents to three-dimensional (3D) supramolecular framework by O1W-H1WB…O1 as well as N2-H2…O2 interactions.CCDC:762259. 相似文献
194.
195.
The Eu(III) ion, as a luminescent probe, is incorporated into a novel nanotube-contained polyorganosiloxane (POS), which is
obtained by coupling of ladderlike polyvinylsilsesquioxane (Vi-T) with tetramethyldisiloxane (H-MM) via hydrosilylation, to
form POS-Eu(III) composite. The results from fluorescent study demonstrate that the composite is actually a host-guest clathrate
which includes the Eu(III) ions in the tubelike cavity of POS and moreover, the supramolecular clathrate exhibits an obvious
energy transfer process which converts the UV light absorbed by POS into the visible light generated from the Eu(III) luminescence.
Molecular simulation also gives support to the formation of such a clathrate and thus results in energy transfer process.
Project supponed by the Research Foundation of Molecular Science Center and Director of Institute of Chemistry, the Chinese
Academy of Sciences, and Foundation of Organic Solid Laboratory, the Chinese Academy of Sciences. 相似文献
196.
In analytical Raman spectroscopy it becomes increasingly important to employ a procedure for the correction of the relative intensity of Raman spectra. The determination of the intensity response function of a Raman instrument traditionally has been carried out through a white light source that has been calibrated for its relative spectral irradiance. While this method will furnish a correction curve to yield spectra corrected to relative Raman intensity, it is often cumbersome and fraught with experimental difficulties that can profoundly affect the reliability of the correction procedure. An alternate methodology that permits a simplified calibration of the Raman instrument response function is based on the use of luminescent glass standards that transfer a white light calibration onto the Raman measurement system. In this procedure, a measurement of the luminescence of an intensity standard, whose relative irradiance has been determined, provides a means to establish the instrument response function. Correction of measured spectra by this function furnishes spectra that are free of instrumental intensity artifacts. Based on this approach, NIST is developing a series of Standard Reference Materials (SRMs) for the calibration of Raman intensity. This process, and the results obtained thereby, is described for Raman spectroscopy measurements employing 785nm excitation. The procedure is valid for both macro-sampling and micro-sampling Raman work. 相似文献
197.
1 INTRODUCTION As is well known, some transition metal ions play an important role in controlling the behavior of many biological macromolecules and produce pro- found effects on their biological actions, medicine and people’s health[1~3]. Zinc is an essential com- ponent of many proteins. In the active sites of zinc enzymes, zinc is bound to the nitrogen of imidazole groups and oxygen of carboxylate groups of amino acids[4~6]. Additional interest in these proteins lies in the fact th… 相似文献
198.
In the context, SrxY10−x(SiO4)y(PO4)6−yO2 doped with 1 mol%Eu3+ (x = 2, y = 6; x = 4, y = 4; x = 5, y = 3; x = 8, y = 0) were synthesized by using 3-aminopropyl-triethoxysilane (APES) as the sources of the silicate network. X-ray diagrams confirm that SrxY10−x(SiO4)
y(PO4)6−yO2: Eu3+ solid solutions are formed as a pure apatitic phase. The SEM picture shows that there exist some novel unexpected coral like morphological structures. The luminescent intensity is the strongest for the host composition of Sr4Y6(SiO4)4(PO4)2O2 although the effect of the composition on the luminescent intensity is little. 相似文献
199.
Vitaliy Smokal Oksana Kharchenko Yuriy Karabets Andrii Kysil Oksana Krupka 《Molecular Crystals and Liquid Crystals》2018,672(1):11-17
ABSTRACTIn this work we report preliminary results obtained for methacrylic polymers incorporating aurone side-group as photochemical active molecule. The aurone polymers were obtained by a three-step synthetic approach: (2Z)-6-hydroxy-2-(4-R-benzyliden)-1-benzofuran-3(2H)-ones were synthesized by using condensation reation of 6-hydroxybenzofuran-3-one with benzaldehydes; then methacrylate monomers were synthesized by reaction the alcohols with methacryloyl chloride; and the polymers were synthesized by free radical polymerization. Polymers were characterized by 1HNMR spectroscopy and DSC techniques. Their physicochemical properties are determined by absorption, fluorescence excitation and emission spectroscopies. 相似文献
200.
本文通过对Tm(Ⅲ)-苯甲酰异羟肟酸(BHA)体系的发射光谱和激发光谱分析,研究了铥、镱和钇离子对Tb-BHA体系的发光性质的增强作用。测得了增敏离子的最佳浓度分别为1.8×10-4mol/L(Tm3+),1.5×10-4mol/L(Yb3+)和2.0×10-4mol/L(Y3+).并对RE-BHA(RE=Tm,Yb,Y和Tb)的固态配合 相似文献