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Zusammenfassung Es wird über eine Methode zur Bestimmung von Halogenidionen in Halogenidgemischen berichtet. Die Endpunktindikation erfolgt nach dem Prinzip der Polarisationsspannungstitration und liefert scharf ausgeprägte Titrationsendpunkte in der Reihenfolge der Schwerlöslichkeit der Ag-Halogenide. Insbesondere wird auch der für Serienanalysen erforderlichen Einfachheit und geringen Störanfälligkeit Rechnung getragen. Das Verfahren eignet sich für die Analyse anorganischer Halogenidgemische, für die Bestimmung von CN- und SCN -Ionen und für die Analyse organischer Halogenverbindungen im Makro- und Halbmikromaßstab nach deren Aufschluß. Die Meßanordnung kann außerdem für die Bestimmung von Kalium und für die Endpunktindikation einiger chelatometrischer Titrationen eingesetzt werden.
Summary A method is described for the determination of halogenide in mixtures of halogenides. End points are sharply indicated by the polarisation titration technique in the order of solubility of the silver halogenides. The method is suitable for the analysis of mixtures of inorganic halogenides, for the determination of CN and SCNions, and for the analysis of organic halogen compounds in macro and semimicro scale after decomposition. For routine analyses it offers the advantage of being simple and only slightly liable to interferences. Moreover, the assembly can be used for the determination of potassium and for the end point indication in some chelatometric titrations.
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Zusammenfassung Es wurde die ionophoretische Trennung von ReCl6 2–, ReBr6 2– und ReO4 unter Verwendung verschiedener Papiersorten untersucht. Am geeignetsten erwies sich das Papier 2045 b Gl von Schl. & Sch.
Summary The ionophoretic separation of ReCl6 2–, ReBr6 2–, and ReO4 has been examined using different kinds of paper. Best results have been obtained with the paper 2045 b Gl from Schleicher & Schüll.


Herrn Prof. G. Brauer danke ich für Förderung. Für die Überlassung von Rheniumverbindungen bin ich der Fa. W. C. Heraeus, Hanau, verpflichtet. Die Neutronenaktivierung wurde freundlicherweise von den Herren Dr. Marth und Dr. Köhler von der Reaktorstation in Garching bei München vorgenommen. Das Bundesministerium für Atomkernenergie und Wasserwirtschaft unterstützte die Untersuchung durch eine Sachbeihilfe.  相似文献   

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0引言手性环氧化物是合成许多天然产物、光学活性材料、光学活性药物等的重要中间体[1]。上世纪60年代以来,手性过渡金属配合物作为烯烃不对称环氧化的催化剂越来越受到人们的重视[2]。研究表明,某些席夫碱金属配合物具有仿酶催化活性,在仿酶催化剂的合成及应用方面占有重要地位[3]。目前,人们将水杨醛衍生物与光学活性胺的席夫碱金属配合物用于不对称环氧化、不对称环丙烷化等反应,具有很高的对映体选择性[4]。同时发现配体的电子效应直接影响配合物的催化活性和对映体选择性。为进一步研究配体的电子性能对配合物催化性能的影响,我们设计…  相似文献   

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The interaction between the radical anions C60 ·− and divalent d- and f-metal (Co, Fe, Ni, Mn, Eu, Cd) cations in DMF and acetonitrile-benzonitrile (AN-BN) mixture was studied. Black solid polycrystalline salts (C60 ·−)2{(M2+)(DMF) x } (x = 2.4–4, 1–6) containing the radical anions C60 ·− and metal(ii) cations solvated by DMF were prepared for the first time and their optical and magnetic properties were studied. The salts containing Co2+, Fe2+, and Ni2+ are characterized by antiferromagnetic interactions between the radical anions C60 ·−, which result in unusually large broadening of the EPR signal of C60 ·− upon lowering the temperature (from 5.55–12.6 mT at room temperature to 35–40 mT at 6 K for Co2+ and Ni2+). The salts containing Mn2+ and Eu2+ form diamagnetic dimers (C60 )2, which causes a jumpwise decrease in the magnetic moment of the complexes and disappearance of the EPR signal of C60 ·− in the temperature range 210–130 K. A feature of salt 6 is magnetic isolation of the radical anions C60 ·− due to the presence of diamagnetic cation Cd2+. The salts prepared are unstable in air and decompose in o-dichlorobenzene or AN. Reactions of C60 ·− with metal(ii) cations in AN-BN mixture result in decomposition products of the salts that contain neutral fullerene dimers and metals solvated by BN. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1909–1919, September, 2008.  相似文献   

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以商用活性炭(AC)为原料,分别采用磷酸和氢氧化钠改性的方法制备了两种不同的改性活性炭电极材料.采用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、 Brunauer-Emmett-Teller(BET)测试、傅里叶变换红外光谱(FTIR)和X射线光电子能谱(XPS)等手段以及电化学分析方法,对改性前后活性炭材料的表面性质和电化学性能进行了探究.结果表明, H3PO4改性使活性炭的孔隙分布更加密集, NaOH改性使活性炭表面的孔隙结构更加清晰均匀; H3PO4和NaOH改性均使活性炭的比表面积增加.循环伏安测试结果表明,改性前后活性炭电极在低扫描速率下均具备良好的双电层特性,并且两种改性处理均能提高活性炭电极的比电容;当扫描速率为5 mV/s时,未改性、 H3PO4以及NaOH改性活性炭电极的比电容分别为36.51, 77.25和85.19 F/g.电吸附实验结果证明,两种改性活性炭电极对Co2+, Mn2+和Ni2+均有较好的去...  相似文献   

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A novel chiral Salen ligand with a glucose moiety was synthesized from the condensation of 1,2:5,6-di-O-isopropylidene-3-O-methylene-[5-(3-tert-butyl-2-hydroxy benzaldehyde)]-α-D-glucofuranose with (1R,2R)-1,2-diaminocyclohexane. Several chiral complexes of Mn3+, Fe3+, Co2+ and Cu2+ were prepared from this ligand. Both the ligand and the complexes were characterized by elemental analysis, NMR, IR, MS, and UV-Vis.  相似文献   

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Summary For the convenient and sufficiently accurate determination of AsO4 3– ions in technical products containing different filling, suspending and colouring materials, as well as impurities—e.g. for the assay of arsenate containing plant protecting materials—the following procedure is recommended.About 5 g of the sample is dissolved, resp. extracted with 4 N hydrochloric acid, and aliquots of the clear filtrate are titrated after elimination of the interfering metal ions by combining them with complexing agents (potassium cyanide and disodium ethylenediamin tetraacetic acid) in a properly buffered medium. The titration with 0.1 M MgSO4 solution is conducted in the presence of eriochrome black T solution as indicator, first time for eliminating the excess of EDTA added, and afterwards to determine the AsO4 3– ions, after adding about 40% of ethanol.The procedure may be useful chiefly for serial routine analyses.The authors are indebted to engineer L. Fokássy, department leader at the State Institute for Agricultural Quality Control, as well as to engineeress P. Fodor and Mr. Gy. Josepovits, scientific collaborators of the Research Institute for Plant Protection, for kindly supplying some of the samples for the experiments.  相似文献   

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Three new heteronuclear complexes [Ru(NO)(NO2)4(OH)M(Py)3] (M = Co2+, Ni2+, Zn2+) were synthesized and structurally characterized. In all compounds, the [Ru(NO)(NO2)4(OH)] fragment is coordinated to the M atom by a bridging OH and two bridging NO2 groups. The coordination environment of the metal also includes three pyridine nitrogen atoms. Thermal decomposition of cobalt and nickel complexes in an inert atmosphere yields bimetallic solid solutions. Original Russian Text ? G.A. Kostin, A.O. Borodin, Yu.V. Shubin, N.V. Kurat’eva, V.A. Emelyanov, P.E. Plyusnin, M.R. Gallyamov, 2009, published in Koordinatsionnaya Khimiya, 2009, Vol. 35, No. 1, pp. 57–64.  相似文献   

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将过渡金属配合物阳离子([M(DETA)2]n+(M=Cu2+,Ni2+,Co3+;DETA=Diethylenetriamine,二乙烯三胺)作为客体插入层状MnPS3层间得到了相应的3个夹层化合物。通过X-射线粉末衍射、元素分析和红外光谱对夹层化合物的结构进行了表征。结果表明,与主体MnPS3 0.65 nm的层间距相比较,夹层化合物(Mn0.88PS3[Cu(DETA)2]0.12)的层间距扩大了0.32 nm,由此推测客体[Cu(DETA)2]2+在层间以平面四方的配位形式存在,而另2个夹层化合物(Mn0.79PS3[Ni(DETA)2]0.21和Mn0.74PS3[Co(DETA)2]0.17)的层间距扩大了0.48 nm,说明客体[(M(DETA)2]n+,M=Co3+,Ni2+) 在主体层间以八面体配位形式存在。磁性测试结果表明过渡金属离子[(M(DETA)2]n+(M=Cu2+,Co3+)的插入能引起主体MnPS3的磁性在35~40 K发生由顺磁向亚铁磁性的转变并表现自发磁化,而客体[Ni(DETA)2]2+却使夹层化合物的反铁磁相互作用增强,抑制了自发磁化的发生。  相似文献   

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水热条件下,合成了三个新的配合物[Ni(en)3] (ndt) ·H2O 1, [Co(en)3] (ndt) ·H2O 2 和[Mn(en)3] (ndt) ·H2O 3。晶体结构通过X-射线单晶衍射进行了表征。三个配合物均属于单斜晶系,Cc空间群。[M(en)3]2+阳离子、ndt阴离子和结晶水分子通过氢键自组装出相同结构的三维网。通过紫外-可见-近红外漫反射光谱对这三个配合物的光吸收性能和能带进行了测定。  相似文献   

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