在L-缬氨酸介质中应用聚二苯并-18-冠醚-6-分离铈（III)

 A column chromatographic method has been developed for the separation and determination of cerium(Ⅲ) using poly［dibenzo-18-crown-6］. The separation was carried out in L-valine medium. The adsorption of cerium(Ⅲ) was quantitative from 1×10-1 to 1×10-4 mol/L L-valine. Amongst the various eluents, 1.0-8.0 mol/L hydrochloric acid, 1.0-8.0 mol/L hydrobromic acid, 1.0-8.0 mol/L perchloric acid, 1.0-2.0 mol/L sulfuric acid and 4.0-5.0 mol/L acetic acid, were found to be the efficient eluents for cerium(Ⅲ). The capacity of poly［dibenzo-18-crown-6］ for cerium(Ⅲ) was （0.428±0.01） mmol/g. The method was applied to the separation of cerium(Ⅲ) from associated elements link uranium(Ⅵ) and thorium(Ⅳ). It was also applied for the determination of cerium(Ⅲ) in geological samples. The method is simple, rapid and selective with good reproducibility (approximately±2%).     

Kinetics and Mechanism of Iridium(Ⅲ)-Catalyzed Oxidation of Ethanol Amine by Cerium(Ⅳ) in Sulfuric Acid Media

In this study, the kinetics and mechanism of the iridium(Ⅲ)-catalyzed oxidation of ethanol amine(EAN) by cerium(Ⅳ) in a sulfuric acid medium was investigated using titrimetric technique of redox in a temperature range of 298-313 K. It was found that the reaction is of first order with respect to Ce(Ⅳ) and Ir(Ⅲ), and a positive fractional order with respect to EAN. It was also found that the pseudo-first-order([EAN](》)[Ce(Ⅳ)]) rate constant kobs decreases with the increase of [H ] and [HSO-4]. Under the protection of nitrogen gas, the reaction system can initiate the polymerization of acrylonitrile, indicating the generation of free radicals. On the basis of the experimental results, a suitable mechanism was proposed. From the dependence of kobs on the concentration of hydrogen sulfate, Ce(SO4)2 was found to be the kinetically active species. The rate constants of the rate-determining step together with the activation parameters were evaluated.     

Cr(Ⅲ)-羧基配位状态稳定性的理论研究

本文采用模型实验结合密度泛函理论B3LYP方法,研究了单核单齿配位、单核螯合配位、多核单齿配位以及多核双点配位Cr(Ⅲ)的氧化还原稳定性。结果显示,单核单齿配位体系的氧化还原稳定性低于单核螯合配位体系。模型实验与理论预测活性得出的结论一致。在此基础上,计算分析了多核Cr(Ⅲ)离子与羧基形成单齿配位结合和双点单齿配位结合后理论参数的差异。前线轨道能差表明这些配合物中Cr(Ⅲ)的氧化还原稳定性顺序为:单核螯合配位>单核单齿配位>四核双点单齿配位>三核单齿配位>二核单齿配位。研究结果将有益于控制皮革中Cr(Ⅵ)的产生。     

Synthesis and Crystal Structure of Novel Dimer of Bismuth( Ⅲ ) Complex with Dithiotetrahydropyrrolocarbamate:[Bi (S2CNC4H8) 2 (NO3) ]2

A novel dimer of the bismuth ( Ⅲ ) complex with dithiotetrahydropyrroloearbamate, [Bi (S2CNC4H8)2 ·(NO3)]2, was synthesized and the crystal structure was determined by X-ray single crystal diffraction. The crystal belongs to a monoclinic system with space group P21/n, a=0. 64718(13) nm, b=2. 6738(6) nm, c=1. 0423(2) nm, β=106. 384(3)°, Z=4, V=1. 730(3) nm3, Dc=2.163 g/cm3, μ=10. 682 mm-1, F(000)=1072, R= 0. 0329, wR=0. 0659. The structure shows a distorted pentagonal bipyramidal configuration with the seven-coordinated central Bi atom. In the crystal, the molecular packing in the unit cell reveals that the two adjacent molecules are symmetrically linked each other in the dimer by virtue of a couple of Bi-S interaction.     

离子色谱法和原子吸收光谱法测定电镀液中Cr(Ⅵ)和Cr(Ⅲ)

提出一种前处理简单、操作方便、灵敏度高的测定电镀液中Cr(Ⅵ)和Cr(Ⅲ)的分析方法。先用原子吸收光谱法检测电镀液的总铬含量,然后用离子色谱法检测Cr(Ⅵ)的总量,由两者的差值得出Cr(Ⅲ)的含量。原子吸收光谱法检测铬的加标回收率为97.3%～99.5%,检出限(3S/D)为0.01 mg/L。离子色谱法检测Cr(Ⅵ)的加标回收率为92.2%～102.2%,检出限(3S/D)为0.05 mg/L。     

An ion-imprinted polymer supported by attapulgite with a chitosan incorporated sol-gel process for selective separation of Ce(Ⅲ)

The surface ion-imprinting concept and chitosan incorporated sol-gel process were applied to the synthesis of a new attapulgitesupported polymer for selective separation of Ce(Ⅲ) from aqueous solution.The imprinting mechanism of prepared ion-imprinted polymer were discussed with the Characteristics of FT-IR and SEM.Results from the experiments of adsorption capacity and selectivity suggested that ion-imprinted polymer offered a fast kinetics for the adsorption of Ce(Ⅲ) under the optimum conditions. Its m...     

SYNTHESIS, SPECTRAL AND MAGNETIC CHARACTERISATION OF SOME BIMETALLIC ALKOXIDES OF NICKEL(Ⅱ)WITH GALLIUM(Ⅲ)AND ZIRCONIUM(IV)

Some interesting bimetallic isopropoxides of nickel(Ⅱ) with gallium(Ⅲ) and zirconium(Ⅳ), Ni[Ga(OPr~1)_4]_2 and Ni[Zr_2(OPr_1)_9]_2 have been synthesized by the interaction of NiCl_2·2Pr~1OH with K[Ga(OPr~1)_4],and K[Zr_2(OPr~1)_9] respectively, in 1:2 molar ratio. These bimetallic isopropoxides undergo facile alcohol interchange reactions with primary alcohols. However, reactions with tertiary alcohols result in the isolation of partially substituted derivatives with the compositions, Ni[Ga(OPr~1)(OBu~t)_3]_2 and Ni[Zr_2(OPr~1)_3(OBu~t)_6]_2. Characterisation of these derivatives has been made on the basis of elemental analyses, infrared, electronic spectral and magnetic susceptibility measurements. These studies suggest an octahedral geometry for nickel(Ⅱ) in the primary bimetallic alkoxides, while in the case of secondary and tertiary derivatives, an equilibrium is suggested between octahedral and tetrahedral forms.##属性不符     

Coordination-driven self-assembly of dibenzo-18-crown-6 functionalized Pt(Ⅱ) metallacycles

Coordination-driven self-assembly was used to construct two metallacycles of a dicarboxylatefunctionalized dibenzo-18-crown-6 in combination with either a 0° anthracene-based clip-type acceptor or a 60° phenanthrene-based acceptor. The angularities of these moieties make them suitable for the formation of a [2 + 2] rectangle and a [3 + 3] triangle, respectively. The synthesis, characterization and host-guest chemistry of two metallacycles were described and supported by³¹P{¹     

Synthesis and Crystal Structure of a New Praseodymium(Ⅲ)-Copper(Ⅱ) Polymeric Complex: [Pr2Cu3(L1)6]n (H2L1=NH{CH2COOH}2)

A novel polymeric Pr2Cu3 complex of iminodiacetic acid (H2L1=NH{CH2COOH}2) [Pr2Cu3(L1)6]n , 1, has been synthesized and structurally characterized. The title complex Pr2Cu3O24N6C24H30 (Mr=1258.97) crystallized in trigonal space group Pc1 (No. 165) with a = 13.424(4), c=14.752(6)(); V=2303(1)()3; F(000)=1226; λ(MoKα)=35.2 cm-1; Dc=1.820 g.cm-3; Z=2. The final R and Rw are 0.072 and 0.081 respectively for 1412 reflections with I>3σ(I). In crystal 1, the Pr3+ ion is nine-coordinated by 6 O atoms from three bidentate chelating carboxylate groups and 3 O atoms from three anti-anti bridging carboxylic groups of six L1 ligands; the Cu2+ ion is six-coordinated by 4 O and 2 N atoms from two pentadentate L1 ligands. Each pair of Pr(Ⅲ) atoms is bridged by three L1 ligands, each of which also chelates with one copper(Ⅱ) ion, thus forming a Pr2Cu3 cluster unit. Such cluster units are cross-linked by flexible L1 ligands into a three-dimensional coordination framework.     

HEH[EHP]萃取Fe(Ⅲ)的动力学研究

用两相充分混合法,在298±1K下研究了HEH[EHP]-正庚烷-1.0mpL·L^-1(Na,H)NO₃体系中萃取Fe(Ⅲ)的动力学过程。认为界面慢反应为速率控制步骤。     

Crystal Structure Analysis of Tetras[L-tris(ethylenediamine) cobalt(Ⅲ)] tris[hexacyanoruthenate(Ⅱ)]

1 INTRODUCTION The tris(ethylenediamine) cobalt (Ⅲ) complex in which there are L and D configurations is one of the very interest cations due to the chirality among research complexes and the characterization of reaction on the ion-pair charge-transfer transitions. It has been mentioned in a lot of examples on the chirality and the structure, such as [L-Co(en)3]- [?Co(edta)]2Cl?0H2O[1], [(+)DCo(en)3]Cl3稨2O[2], [(+)-Co(en)3?-)-Cr(en)3]Cl?.1H2O[3], [()-Co(en)3] (SCN)3[4], [(+)D…     

Cr(Ⅵ)及Cr(Ⅲ)混合物中Cr(Ⅵ)的原子吸收测定——Cr(TTA)_3在石墨炉中挥发条件的研究

在pH5.7的乙酸-乙酸钠缓冲介质中,噻吩甲酰三氟丙酮(TTA)与Cr(Ⅲ)络合,生成的络合物具有挥发性.Cr(Ⅵ)在同样条件下不发生反应.利用此特点可实现Cr(Ⅵ)和Cr(Ⅲ)在石墨炉内分离并测定Cr(Ⅵ).研究了影响Cr(Ⅲ)与TTA络合的反应酸度、试剂加入量、静置时间等条件,并对石墨炉内定量挥发Cr(Ⅲ),保留Cr(Ⅵ)的原子化条件进行了探讨,所拟定的方法用于合成水样分析,获得满意结果.     

萃取-火焰原子吸收法测定河水中的Cr(Ⅵ)和Cr(Ⅲ)

铬被广泛应用于电镀、印染、制革及纺织等行业,是造成河水和土壤铬污染的主要原因。铬在河水中主要以Cr(Ⅵ)和Cr(Ⅲ)形式存在,其价态不同,毒性也不同。适量Cr(Ⅲ)为人体所必需,以维持正常的新陈代谢;而Cr(Ⅵ)则被证明由于其强氧化性和对皮肤的高渗透性可以通过皮肤接触引起皮肤的溃烂、发炎,甚至导致生物的癌变,所以必须对样品中的Cr(Ⅵ)和Cr(Ⅲ)进行分别测定。     

Extraction chromatographic study of aluminium(III) and mutual separation of aluminium(III), gallium(III), indium(III) and thallium(III) with N-n-octylaniline

A selective method has been developed for extraction chromatographic studies of aluminium(III) and its separation from several metal ions with a chromatographic column containing N-n-octylaniline (liquid anion exchanger) coated on silanized silica gel as a stationary phase. The aluminium(III) was quantitatively extracted with the 0.065 mol/L N-n-octylaninine from 0.013 to 0.05 mol/L sodium succinate at a flow rate of 1.0 mL/min. The extracted metal ion has been recovered by eluting with 25.0 mL of 0.05 mol/L hydrochloric acid and estimated spectrophotometrically with aurintricarboxylic acid. The effects of the acid concentration, the reagent concentration, the flow rate and the eluting agents have been investigated. The log-log plots of distribution coefficient (KdAl(III)) versus N-n-octylaniline concentrationin 0.005 and 0.007 mol/L sodium succinate gave theslopes 0.5 and 0.7 respectively and showed theprobable composition of theextracted species was 1:1 (metal to amine ratio) and the nature of extracted species is [RR''NH2+ Al succinate2-] org. .The extraction of aluminium(III) was carried out in the presence of various ions to ascertain the tolerance limit of individual ions. Aluminium(III) has been separated from multicomponent mixtures, pharmaceutical samples and synthetic mixtures corresponding to alloys. A scheme for mutual separation of aluminium(III), indium(III), gallium(III) and thallium(III) has been developed by using suitable masking agents. The method is fast, accurate and precise.     

薄层光谱电化学方法研究[Ag(lO_6)_2]~(7-)和[Cu(lO_6)_2]~(7-)的阴极还原

在碱性介质中只有少数氧化剂如Ag(Ⅲ)及Cu(Ⅲ)仍有较强的氧化性,因此研究Ag(Ⅲ)、Cu(Ⅲ)络合物阴极还原的电极电势、电子转移数及还原机理,对于深入了解它们作为氧化剂时的氧化还原特性是有帮助的.本文用薄层光谱电化学方法测定了二过碘酸合银(Ⅲ)、络离子在不同pH条件下还原反应的E~0′和电子转移数(n),并由此推断阴极还原反应机理,还用同样方法研究了二过碘酸含铜(Ⅲ)络离子的阴极还原.     

Preparation and crystal structure of bis(dibenzo-18-crown-6)-(tetrachlorocuprato(II)-Cl,Cl′, Cl″, Cl‴)dipotassium diaqua(dibenzo-18-crown-6)potassium dichlorocuprate(I)-dibenzo-18-crown-6

New mixed complex compound bis(dibenzo-18-crown-6)(tetrachlorocuprato(II)-Cl, Cl′, Cl″, Cl?) dipotassium diaqua(dibenzo-18-crown-6)potassium dichlorocuprate(I)dibenzo-18-crown-6 [(CuCl₄)[K(Db18C6)]₂]·[K(Db18C6)(H₂O)₂]⁺·[CuCl₂]^?·Db18C6 was prepared and its structure was studied by the X-ray structural analysis. The structure was found to be disordered. The asymmetric part of its unit cell contains 1/4 of each of its four components. For a given [CuCl₄]^2? anion its Cu²⁺ cation is disordered over two equally probable positions and its independent Cl atom is disordered over three positions differing by occupancy. In this structure two [K(Db18C6)]⁺ fragment of the complex molecule and the complex cation [K(Db18C6)(H₂O)₂]⁺ are of guest-host type with K⁺ cation as the guest. In this structure the statistically disordered alternating cations and Db18C6 molecules form infinite chains. The statistically disordered [CuCl₂]^? anions also form infinite chains.     

3D异金属Bi(Ⅲ)-Pr(Ⅲ)配位聚合物的合成、晶体结构和热稳定性

在水溶液中合成了双金属配位聚合物({[(NO3)(H2O)3Pr(μ4-Hedta)Bi-(NO3)2]·2H2O}2)n, 并通过元素分析、红外光谱和X射线单晶衍射等手段进行了表征. 该配合物为单斜晶系, P2(1)/n空间群, a=1.26831(18) nm, b=0.82189(12) nm, c=2.3755(3) nm, β=105.055(2)°, R=0.0429, V=2.3913(6) nm3, Z=4. Bi(Ⅲ)-Pr(Ⅲ)间通过配阴离子Hedta3-中4个羧基的桥联作用构建配合物的3D结构. TG-DSC结果表明, 该配合物热分解经历脱水、配体分解以及盐分解过程, 残余物为Bi-Pr-O的三元复合氧化物.     

以氯醌酸二价阴离子为桥联配体的Fe(Ⅲ)-Fe(Ⅲ)和Mn(Ⅱ)-Mn(Ⅱ)双核配合物的合成与磁性

基于铁和锰的双核配合物在生物氧化还原过程中的重要作用及在化学的氧化还原过程中可能做为催化剂的应用前景,本文合成了两个新的以氯醌酸二价阴离子为桥联配体的Fe(Ⅲ)双核和Mn(Ⅱ)双核配合物:[Fe_2(phen)_4(μ-CA)](ClO_4)_4·2H_2O(1)和[Mn_2(phen)_4(μ-CA)](ClO_4)_2·3H_2O(2)(phen=1,10菲咯啉;CA=氯醌酸二价阴离子)。经元素分析、IR、电子光谱及磁性等测定,对两配合物进行了表征。     

Synthesis and Crystal Structure of (CH2)3(3, 5-Me2Pz)2·[PhBr2Sn(CH2)SnBr2Ph]·2HBr·2H2O (Pz = pyrazole)

The reaction of bis(dibromophenylstannyl)methane with 1, 3-bis(3, 5-dimethyl- pyrazol-1-yl)propane in a 1:1 or 1:2 ratio yields only 1:1 adduct which partly hydrolyzes to the title complex (C26H38Br6N4O2Sn2, Mr = 1155.42) during crystal growing. The title complex is of triclinic, space group P ī with a = 10.886(1), b = 12.508(1), c = 13.879(1) ?, α = 85.762(2), β = 85.159(2), γ = 84.020(2)°, V = 1868.8(4) ?3, Z = 2, Dc = 2.046 g/cm3, λ(MoKα) = 0.71073 ?, μ = 7.778 mm-1, F(000) = 1088, R = 0.0488 and wR = 0.1157 for 7560 observed reflections with I ≥ 2σ(I). The crystal structure analysis indicates that there is no direct interaction between the ligand and bis(dibromophenylstannyl)methane, and two tin atoms are bridged by two bromide atoms from the partial hydrolysis of this adduct.     

离子交换分离富集HG-AFS法测定土壤水溶态Se(Ⅳ)和Se(Ⅵ)

选用D296阴离子交换树脂分离富集土壤水溶态无机硒,研究了分离富集Se(Ⅳ)和Se(Ⅵ)的实验条件。分别用体积分数为0.1%和10%HCl洗脱土壤水溶态Se(Ⅳ)和Se(Ⅵ),然后用HG AFS对其进行测定,Se(Ⅳ)和Se(Ⅵ)的RSD(n=7)分别为4 3%和1.4%,检出限分别为0.22μg L和0.13μg L。