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1.
本文研究了1,2-双(正-丙基硫代)乙烷(BPrTE)、1,2-双(正-戊基硫代)乙烷(BATE)、1,2-双(正-辛基硫代)乙烷(BOTE)和1,2-双(苯基硫代)乙烷(BPTE)对银的萃取.讨论了硝酸浓度、稀释剂RS(CH_2)_2SR(L)中R基因对萃取银的影响.L可从大量贱金属和氯化物中定量地萃取银,银和配体可形成组成为Ag:L=2.5:1,2:1,3:2,1:1,2:3,1:2系列配合物.  相似文献   

2.
1 INTRODUCTION Polythiotungstate complexes can be prepared from the protonation of one sulfur atom of [WS4]2- and subsequent intramolecular redox reactions[1,2]. For example, [(S)2W(m-S)2W(m-S)2W(S)2]2 was formed by the acidification of a diluted aqueous solution of (NH4)2[WS4] with dilute H2SO4[3]. When a diluted aqueous solution containing [WS4]2 was acidified with 0.1mol/L HCl, [(S)2W(m-S)2(O)- W(H2O)(m-S)2W(S)2]2 was formed[4]. [(S)2W- (m-S)2(S)W(m-S)2W(S)2]2 was form…  相似文献   

3.
The reaction of 5-sulfosalicylic acid(H3-SSA) with o-phenanthroline(Phen),NaOH,and Mcl2(M=Zn,Cu) affords Zn(H-SSA)(Phen)(H2O)2(1) and Cu(H-SSA)(Phen)(H2O)2 (2),respectively ,compounds 1 and 2 are characterized by elemental analysis,IR,fluorescence spectra and single crystal Xray diffraction analysis.The X-ray diffraction analyses reveal that compounds 1 and 2 are isostructure.The 5-sulfosalicylic acid ligand loses two protons at the sulfo-group and carboxylic group during the reaction.The Zn(II) and Cu(II)ions are sixcoordinated and adopt distorted octahedral geometry,which are surrounded by two N atoms from Phen,two O atoms from two water molecules,one O atom from-SO3 group and one oxygen from carboxylic group of the other H-SSA.Compounds 1 and 2 have unprecedented one-dimensional linear chain formed by a repeating mononuclear structureal unit.which is bridged by H-SSA.The fluorescence intensity of 1 and 2 is stronger than that of Phen and H3-SSA at 400nm.The lowest excited single states of these complexes are assigned as mainly Phen localized 1(π π),The antibacterial activity test shows that compounds 1 and 2 strongly inhibit the growth of Streptococcus haemolyticus,Straphylococcus aureus and Escherichia coli.  相似文献   

4.
利用Se(Ⅳ ) ,Te(Ⅳ )对盐酸肼与KBrO3的氧化还原反应的催化效应 ,反应产物与甲基橙褪色变化来度量反应速率。分别在 2 0和 2 5℃的条件下 ,在波长 5 2 5nm处测定反应速率。其速率与Se(Ⅳ )和Te(Ⅳ )浓度呈线性关系。用PLS方法拟合试验数据 ,获得了反应速率与Se(Ⅳ )、Te(Ⅳ )浓度间的关系式 ,从而求出结果。硒和碲的检出限分别为 1.5和 3 .0ng·ml- 1;线性范围分别为 0 40和 0 75ng·ml- 1;相对标准偏差分别为 3 .0 %和 3 .2 %。用此法检测国家标准样品结果基本一致。方法简便快速 ,准确可靠。  相似文献   

5.
马春林  李凤 《中国化学》2003,21(2):146-152
Three distannoxane dimers[(PhCH2)2(Cl)SnOSn(X)(CH2Ph)2]2(X=Cl,OMe,OEt)were prepared by the hydrolytic reaction of (PhCH2)2SnCl2 with sodium alkoxides.The compounds are assigned tetranuclear distannoxane structures in solid state.which contain the so-called ladder arrangement with a central planar Sn2O2 four-membered ring.The endo-and exo-cyclic Sn atoms are both five-coordinate,and have distorted trigonal bipyramidal geometries.A variety of hydrolyses of(PhCH2)2SnCl2 were performed and these dimers were characterized by IR,^1H NMR spectroscopy and X-ray diffraction analysis.  相似文献   

6.
合成了三元混配配合物[Cu(L-Ile)(Phen)(H_2O)(ClO_4)](L-Ile=L=异亮氨酸,phen=1,10-邻菲咯啉),通过红外光谱、紫外-可见光谱、摩尔电导率、X射线单晶结构分析,对配合物进行了表征。该晶体属单斜晶系,P2_1空间群,晶胞参数:a=1.1704(5)nm,b=0.8090(5)nm,c=2.1822(5)nm,β=98.061(5)°,Z=2,D_x=1.60Mg·m~(-3),R_1=0.0462,wR_2=0.1225。每个配合物分子中Cu(Ⅱ)离子与一个L-Ile(N,O)配体、一个Phen(N,N)配体、一个H_2O(O)配体及一个Cl_O~-(O)形成六配位的畸变八面体构型。本文还用电位滴定法测定了配合物的稳定常数,结果表明,配合物具有高的稳定性。  相似文献   

7.
在(CH_3)_3NO存在下,PPh_3取代M(CO)_5(M=Fe,Ru,Os)中CO的反应速度遵循二级速度定律,分别与[M(CO)_5]和[(CH_3)_3NO]的一次方成正比,与[PPh_3]无关。反应速度按FeRu>Os的次序约减小4倍。 1 实验方法 典型的动力学实验中,将(CH_3)_3NO的C_2H_5OH溶液和PPh_3的己烷溶液分别用注射器加到体积合适的烧瓶中,再注入Fe(CO)_5并迅速震荡烧瓶,再取出一部分反应液立即注入充N_2  相似文献   

8.
1INTRODUCTIONTheSchiffbasesderivedfromb-diketonesandaliphaticamineshavebeenshowntoexistastheketo-amines.However,ifsubstituentseitherattheketooraminogrouparearomatic,itmaybeexpectedtheenoliminewillbethefavoredtautomericform[1].Recently,someSchiffbasesderivedfromTTA(4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione)andPMBPhavebeenstudiedbyWang[2]andYu[3]etal.Inordertostudytherelationshipbetweenthestructuresandperformancesofthesecompounds,thetitlecom-poundwillbereportedherein.2EXPERIMENT…  相似文献   

9.
曾正志 《中国化学》2002,20(5):474-478
Two new Complexes(Cp)2Ti(Cin)2and (CP2)Ti(Tzea)2(CP=Cyclopentadienyl η^5-C5H5)have been synthesized in THF by the reaction of HCin(Cincofen,2-phenylquinoline-4-carboxylic acid)or HTzea(5-phenyltetrazolyl-2-ethanoic acid)with(Cp)2TiCl2,and characterized by elemental analyses,IR,1H NMR and 13C NMR,UV spectra,molar conductivity,TGDTA.In the complexes the carboxyl groups are coordinated to Ti(IV)in a monodentate manner,The inhibitory actions of the complexes on mice ear tumefaction caused by croton oil and the rat foot granulation growth produced by cotton wool are higher than those of the corresponding ligands HCin,HTzea and [(Cp)2TiCl2],while their toxicities are lower than those of the free ligands.ηη  相似文献   

10.
Asymmetric hydrogenation of (6-methoxyl-2-naphthyl)-2-acrylic acid catalyzed by cinchona modified Pd(0)-α-FeOOH was reported and ee‘s of (S)-( )-2-(6‘-methoxyl-2-naphthyl)propionic acid ((S)-( )-naproxen) up to 98% was achieved firstly.  相似文献   

11.
This work deals with the type and incidence of nonclassical Si--H and H--H interactions in a family of silylhydride complexes [Fe(Cp)(OC)(SiMe(n)Cl(3-n))H(X)] (X=SiMe(n)Cl(3-n), H, Me, n=0-3) and [Fe(Cp)(Me(3)P)(SiMe(n)Cl(3-n))(2)H] (n=0-3). DFT calculations complemented by atom-in-molecule analysis and calculations of NMR hydrogen-silicon coupling constants revealed a surprising diversity of nonclassical Si--H and H--H interligand interactions. The compounds [Fe(Cp)(L)(SiMe(n)Cl(3-n))(2)H] (L=CO, PMe(3); n=0-3) exhibit an unusual distortion from the ideal piano-stool geometry in that the silyl ligands are strongly shifted toward the hydride and there is a strong trend towards flattening of the {FeSi(2)H} fragment. Such a distortion leads to short Si--H contacts (range 2.030-2.075 A) and large Mayer bond orders. A novel feature of these extended Si--H interactions is that they are rather insensitive towards the substitution at the silicon atom and the orientation of the silyl ligand relatively the Fe--H bond. NMR spectroscopy and bonding features of the related complexes [Fe(Cp)(OC)(SiMe(n)Cl(3-n))H(Me)] (n=0-3) allow for their rationalization as usual eta(2)-Si--H silane sigma-complexes. The series of "dihydride" complexes [Fe(Cp)(OC)(SiMe(n)Cl(3-n))H(2)] (n=0-3) is different from the previous two families in that the type of interligand interactions strongly depends on the substitution on silicon. They can be classified either as usual dihydrogen complexes, for example, [Fe(Cp)(OC)(SiMe(2)Cl)(eta(2)-H(2))], or as compounds with nonclassical H--Si interactions, for example, [Fe(Cp)(OC)(H)(2)(SiMe(3))] (16). These nonclassical interligand interactions are characterized by increased negative J(H,Si) (e.g. -27.5 Hz) and increased J(H,H) (e.g. 67.7 Hz).  相似文献   

12.
Huang FQ  Ibers JA 《Inorganic chemistry》2001,40(10):2346-2351
The alkali metal/group 4 metal/polychalcogenides Cs(4)Ti(3)Se(13), Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14) have been synthesized by means of the reactive flux method at 823 or 873 K. Cs(4)Ti(3)Se(13) crystallizes in a new structure type in space group C(2)(2)-P2(1) with eight formula units in a monoclinic cell at T = 153 K of dimensions a = 10.2524(6) A, b = 32.468(2) A, c = 14.6747(8) A, beta = 100.008(1) degrees. Cs(4)Ti(3)Se(13) is composed of four independent one-dimensional [Ti(3)Se(13)(4-)] chains separated by Cs(+) cations. These chains adopt hexagonal closest packing along the [100] direction. The [Ti(3)Se(13)(4-)] chains are built from the face- and edge-sharing of pentagonal pyramids and pentagonal bipyramids. Formal oxidation states cannot be assigned in Cs(4)Ti(3)Se(13). The compounds Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14) crystallize in the K(4)Ti(3)S(14) structure type with four formula units in space group C(2)(h)()(6)-C2/c of the monoclinic system at T = 153 K in cells of dimensions a = 21.085(1) A, b = 8.1169(5) A, c = 13.1992(8) A, beta = 112.835(1) degrees for Rb(4)Ti(3)S(14);a = 21.329(3) A, b = 8.415(1) A, c = 13.678(2) A, beta = 113.801(2) degrees for Cs(4)Ti(3)S(14); a = 21.643(2) A, b = 8.1848(8) A, c = 13.331(1) A, beta = 111.762(2) degrees for Rb(4)Hf(3)S(14); a = 22.605(7) A, b = 8.552(3) A, c = 13.880(4) A, beta = 110.919(9) degrees for Rb(4)Zr(3)Se(14); a = 22.826(5) A, b = 8.841(2) A, c = 14.278(3) A, beta = 111.456(4) degrees for Cs(4)Zr(3)Se(14); and a = 22.758(5) A, b = 8.844(2) A, c = 14.276(3) A, beta = 111.88(3) degrees for Cs(4)Hf(3)Se(14). These A(4)M(3)Q(14) compounds (A = alkali metal; M = group 4 metal; Q = chalcogen) contain hexagonally closest-packed [M(3)Q(14)(4-)] chains that run in the [101] direction and are separated by A(+) cations. Each [M(3)Q(14)(4-)] chain is built from a [M(3)Q(14)] unit that consists of two MQ(7) pentagonal bipyramids or one distorted MQ(8) bicapped octahedron bonded together by edge- or face-sharing. Each [M(3)Q(14)] unit contains six Q(2)(2-) dimers, with Q-Q distances in the normal single-bond range 2.0616(9)-2.095(2) A for S-S and 2.367(1)-2.391(2) A for Se-Se. The A(4)M(3)Q(14) compounds can be formulated as (A(+))(4)(M(4+))(3)(Q(2)(2-))(6)(Q(2-))(2).  相似文献   

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17.
采用传统电子陶瓷工艺制备新型钙钛矿体系(1-x)(K_(0.485)Na_(0.485)Li_(0.03))NbO_3-Pb(Zr_(0.53)Ti_(0.47))O_3陶瓷,研究了该体系陶瓷的介电铁电性能.X射线衍射分析表明:所有陶瓷样品都具有单一的钙钛矿结构,在0.65≤x≤0.75时,出现明显的正交相和四方相的准同型相界区.测试结果表明:陶瓷具有高介电常数.低介质损耗,良好的温度稳定性;获得了饱和的电滞回线,显示了优良的铁电性能.尤其在x=0.75时各项性能达到最佳,其中介电常数ε_r=1590,介电损耗tan δ=0.017,居里温度T_c=295℃,剩余极化强度P,=28.6 μC·cm~(-1),矫顽场强E_c=0.89 kV·mm~(-1).  相似文献   

18.
Crossed molecular beams experiments have been utilized to investigate the reaction dynamics between two closed shell species, i.e. the reactions of tricarbon molecules, C(3)(X(1)Sigma(g)(+)), with allene (H(2)CCCH(2); X(1)A(1)), and with methylacetylene (CH(3)CCH; X(1)A(1)). Our investigations indicated that both these reactions featured characteristic threshold energies of 40-50 kJ mol(-1). The reaction dynamics are indirect and suggested the reactions proceeded via an initial addition of the tricarbon molecule to the unsaturated hydrocarbon molecules forming initially cyclic reaction intermediates of the generic formula C(6)H(4). The cyclic intermediates isomerize to yield eventually the acyclic isomers CH(3)CCCCCH (methylacetylene reaction) and H(2)CCCCCCH(2) (allene reaction). Both structures decompose via atomic hydrogen elimination to form the 1-hexene-3,4-diynyl-2 radical (C(6)H(3); H(2)CCCCCCH). Future flame studies utilizing the Advanced Light Source should therefore investigate the existence of 1-hexene-3,4-diynyl-2 radicals in high temperature methylacetylene and allene flames. Since the corresponding C(3)H(3), C(4)H(3), and C(5)H(3) radicals have been identified via their ionization potentials in combustion flames, the existence of the C(6)H(3) isomer 1-hexene-3,4-diynyl-2 can be predicted as well.  相似文献   

19.
Summary The cation-exchange behaviour of Mn(II), Cd(II), Co(II), Ni(II), Zn(II), Cu(II), Fe(III), Sc(III), Y(III), Eu(III), Dy(III), Ho(III), Yb(III), Ti(IV) and Nb(V) in malate media at various concentrations and pH, was studied with Dowex 50 WX8 resin (200–400 mesh) in the ammonium form. Separation of Fe(III)/Cu(II), Fe(III)/Cu(II)/Zn(II), Fe(III)/Co(II)/Mn(II), Cu(II)/Ni(II)/Mn(II), Fe(III)/Cu(II)/Co(II)/Mn(II), Fe(III)/Cu(II)/Ni(II)/Cd(II), Yb(III)/Eu(III), Sc(III)/Y(III),Sc(III)/Yb(III)/Dy(III) and Nb(V)/Yb(III)/Ho(III) has been achieved, among others.This work was supported by C.N.R. of Italy.  相似文献   

20.
A low barrier in the reaction pathway between the double Rydberg isomer of OH(3) (-) and a hydride-water complex indicates that the former species is more difficult to isolate and characterize through anion photoelectron spectroscopy than the well known double Rydberg anion (DRA), tetrahedral NH(4) (-). Electron propagator calculations of vertical electron detachment energies (VEDEs) and isosurface plots of the electron localization function disclose that the transition state's electronic structure more closely resembles that of the DRA than that of the hydride-water complex. Possible stabilization of the OH(3) (-) DRA through hydrogen bonding or ion-dipole interactions is examined through calculations on O(2)H(5) (-) species. Three O(2)H(5) (-) minima with H(-)(H(2)O)(2), hydrogen-bridged, and DRA-molecule structures resemble previously discovered N(2)H(7) (-) species and have well separated VEDEs that may be observable in anion photoelectron spectra.  相似文献   

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