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11.
采用高温灼烧、硅胶柱层析为分离方法,用傅里叶变换红外光谱法、X射线荧光光谱法作为分析手段,结合溶解与燃烧特性,对一种醋酸纤维素胶板表面处理用滚光油进行了剖析。得到的配方组成是正三十烷(19.06%)、油酸(3.64%)、硬脂酸钠(25.30%)、三氧化二铁与α型三氧化二铝(约50%)。  相似文献   
12.
Two compounds,3-oxo-N-o-tolylbenzo[d]isothiazole-2(3H)-carboxamide (1) and N-(2-methoxyphenyl)-3-oxobenzo[d]isothiazole-2(3H)-carboxamide (2),were synthesized from the initial compound benzo[d]isothiazol-3(2H)-one (BIT) and characterized by 1 H NMR,IR and elemental analysis,respectively.The single crystals of compounds 1 and 2 were obtained and determined by X-ray diffraction analysis.The preliminary results of biological activity experiment show that some of the title compounds exhibited a favorable antimicrobial activity.  相似文献   
13.
Four novel Cu(Ⅰ) complexes,[Cu(o-PYO)(PPh3)2]BF4(1),[Cu(o-PYO)(DPEphos)]BF4(2),[Cu2 (o-PYO)(PPh3)3(CH3CN)](BF4)2(3) and [Cu2(o-PYO)(DPEphos)2 ](BF4)2(4) (o-PYO=2,5bis(pyridyl)-1,3,4-oxadiazole,PPh 3=triphenylphosphine,DPEphos=bis(2-(diphenylphosphanyl)phenyl)ether),have been synthesized and characterized by 1 H NMR,elemental analysis and single-crystal X-ray diffraction.The central cuprous ions in all complexes are surrounded by N and P atoms to form a distorted tetrahedral geometry,although one of the cuprous ions in complex 3 is coordinated by a PPh3 and an acetonitrile molecule due to the steric hindrance and weak coordination ability from monodentate PPh3 ligand.The UV-vis absorption spectra in CH2Cl2 show the characteristic metal-to-ligand charge transfer (MLCT) absorption bands in the region of 360-480nm.Four Cu(I) complexes exhibit yellow to orange-red phosphorescence with the emission maximum at 572,577,562 and 597nm,respectively in the solid state.  相似文献   
14.
In the title coordination compound,[Cu(HDPPZC)(SO4)(H2O)]2 (1,HDPPZC=dipyrido[3,2-a:2,3-c]-phenazine-2-carboxylic acid),has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction,elemental analysis and magnetic susceptibility measurement.It crystallizes in triclinic,space group P1 with a=0.69485(6),b=0.76878(4),c=1.76638(13)nm,α=99.437(6),β=94.690(6),γ=95.735(6)o,V=0.92151(12) nm 3,Z=1,Cu2C38 H24 N 8S2O14,Mr=1007.85,Dc= 1.816 g·cm-3,F(000)=510,GOOF=0.988,the final R=0.0580 and wR=0.0689.The structural analyses reveal that complex 1 shows discrete dinuclear clusters,which are further linked by hydrogen bonding and π·π stacking interactions to form a three-dimensional supramolecular compound.Magnetic measurement shows ferromagnetic and antiferromagnetic exchange interactions in the sample.  相似文献   
15.
A new cadmium(Ⅱ) nitrite complex Cd2(H2C3PIm)2(BDC)(NO2)2(1,H2C3PIm = 2,2'-(1,3-propanediyl)bis(1H-benzimidazole),H2BDC = 1,4-benzenedicarboxylic acid) has been synthesized by solvothermal reaction in formamide,and its structure(C42H36Cd2N10O8,Mr = 1033.61) was determined by single-crystal X-ray diffraction analysis.The crystal belongs to the monoclinic system,space group P21/n with a = 0.9859(5),b = 0.8936(5),c = 2.3188(5) nm,β = 97.576(5)°,V = 2.025(16) nm3,Z = 2,Dc = 1.695 g/cm3,μ(MoKα) = 1.118 mm-1,F(000) = 1036,S = 1.017,the final R = 0.0304 and wR = 0.0752 for 3761 reflections with I > 2σ(I).The centrosymmetric complex 1 contains a dimer in which two distorted octahedral Cd(II) centers are bridged by BDC ligand and chelated by H2C3PIm.The units of the complex are linked via weak N-H···O hydrogen bonds between the nitrito and the BDC ligands,leading to the formation of a 1D zigzag chain along the b axis.The π-π packing interactions contribute to the formation of a three-dimensional supramolecular architecture.The complex exhibits strong photoluminescence at room temperature.  相似文献   
16.
山豆根总黄酮不同提取方法的比较   总被引:2,自引:0,他引:2  
分别采用常规回流提取法、超声提取法、微波辅助萃取法及索氏提取法对中药山豆根进行提取;以芦丁为对照品,采用分光光度法测定提取物中总黄酮的含量;以总黄酮的含量为考察指标,优选出最佳提取方法.结果表明,4种提取方法中,常规回流提取法总黄酮含量最高,微波辅助萃取法和超声提取法总黄酮含量较高,索氏提取法总黄酮含量最低;综合考虑,...  相似文献   
17.
DFT-B3LYP/6-311G** method has been used to optimize molecular geometric structures of 527 polychlorinated fluoranthene(PCFRT) congeners and calculate their thermo-dynamic properties in the ideal gas state,such as heat capacity at constant volume(Cv),entropy(S),standard enthalpy of formation(ΔfH) and standard Gibbs free energy of formation(ΔfG).The relations of Cv,S,ΔfH and ΔfG with the number and position of chlorine atoms have also been explored,from which the relative stability of PCFRT congeners was theoretically proposed according to the magnitude of the relative standard Gibbs free energy of formation(Δr,fG).It was found that some of the PCFRT isomers are in a nonplanar configuration and there are intramolecular Cl…Cl weak interactions in some of the isomers.With increasing the number of chlorine atoms,the values of ΔfH and ΔfG of the most stable PCFRT isomers decrease initially and then increase.The values of ΔfH and ΔfG of PCFRT congeners with the same number of chlorine atoms show a strong dependence on the positions of chlorine atoms.The relative thermodynamic stability of PCFRT isomers is determined mainly by intramolecular adjacent Cl…Cl nuclear repulsive interaction between Cl atoms at two different six-membered rings.Most PCFRT congeners are easier to form thermodynamically than their parent compound.  相似文献   
18.
A novel zinc(Ⅱ) complex of empirical formula,ZnL2(L=anionic forms of S-benzyl-β-N-(2,4-dichlorobenzylidene) hydrazine carbodithioate),has been synthesized and characterized by elemental analysis,IR spectra and single-crystal X-ray diffraction.The crystal belongs to the triclinic system,space group P with a = 9.3168(9),b = 13.0353(13),c = 14.7702(15) ,α = 71.2860(10),= 87.5140(10),γ = 79.4480(10)o,V = 1670.0(3) 3,Z = 2,Mr = 773.93,Dc = 1.539 g/cm3,μ = 1.334 mm-1,F(000) = 784,the final R = 0.0403 and wR = 0.0800 for 4060 observed reflections with I>2(I).In the crystal structure,the zinc(Ⅱ) complex has a distorted tetrahedral geometry in which the zinc ion is coordinated by the nitrogen and sulfur atoms from two Schiff base ligands,respectively.The preliminary bioassay indicates that the Schiff base and its zinc complex exhibit inhibitory activity against the human gastric cancer cell lines(MKN45) and hepatoma cell lines(HepG2).  相似文献   
19.
A new metal-organic coordination polymer [Zn(hfipbb)(e-urea)]n(1,H2hfipbb = 4,4'-(hexafluoroisopropylidene)bis(benzoic acid),e-urea = ethylene urea) has been urothermally synthesized and characterized by elemental analysis and single-crystal X-ray diffraction.The title complex crystallizes in monoclinic,space group P21/c with a = 13.302(4),b = 10.981(3),c = 13.804(4) ,β = 93.587(5)°,V = 2012.3(10) 3,C20H14N2O5F6Zn,Mr = 541.72,Z = 4,Dc = 0.447 g/cm3, = 0.328 mm-1,F(000) = 272,R = 0.0340 and wR = 0.1107 for 4528 observed reflections(I >2σ(I)).In the structure of compound 1,two Zn(Ⅱ) ions are bridged by two carboxylate groups from two hfipbb ligands to form a dinuclear unit,and each dinuclear Zn(Ⅱ) unit is linked with its two adjacent dinuclear units through four hfipbb ligands into an infinite one-dimensional double-chain.The interesting structural feature of compound 1 is that the one-D double-chains are self-interconnected into a three-D supramolecular structure through hydrogen bonds between the coordinated e-urea molecules and carboxylate oxygen atoms(N1 and O2,N2 and O4).  相似文献   
20.
Two new quaternary sulfides,La3Sn0.25GeS71 and Sm3 Sn0.25GeS72,have been synthesized by a facile solid-state reaction,and their crystal structures were determined by singlecrystal X-ray diffraction analysis.The two compounds crystallize in the P6 3 space group,and the crystal data are as follows-La3Sn0.25GeS7:a=10.3335(7),c=5.8455(7),Z=2;Sm3Sn0.25GeS7:a=9.999(3),c=5.787(2),Z=2.Single-crystal analysis indicated that the two compounds consist of three types of building blocks:LnS 8 anti-tetragonal prism,SnS 6 octahedron,and GeS 4 tetrahedron.  相似文献   
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