双席夫碱双-(2,4-二羟基苯乙酮)缩肼的合成及其与铜的荧光猝灭反应

报道了一种新的双席夫碱荧光试剂——双—(2，4—二羟基苯乙酮)缩肼的合成；试剂在492.8nm处有一强荧光峰，当有铜离子存在时，可与试剂形成稳定的配合物而使试剂的荧光猝灭；利用此反应建立了一个荧光测定痕量铜的新方法，测定铜的线性范围为0．0～180．0μg／L，检出限0．02μg／L，方法可应用于矿泉水和水中痕量铜的测定。     

Sorption of Copper(II) Ions by Apple Pectin Modified with Organic Pharmacophores

Russian Journal of Physical Chemistry A - The sorption properties of apple pectin, native and modified by pharmacophores (nicotinic, salycilic, 5-aminosalycilic, and anthroic acids), are...     

Sulfite Oxidation Catalyzed by Manganese(II) Ions: Reaction Kinetics in Excess of Metal Ions

Kinetics and Catalysis - The paper gives a summary of data on the kinetics of oxygen oxidation of sulfite in the presence of manganese(II) salts at ambient temperature in a medium with pH...     

Complex Formation of Copper(II) Ions with Phthalate Ions in Non-Aqueous Solvents

Russian Journal of General Chemistry - Electronic spectra of copper(II) phthalate complexes in non-aqueous solvents were obtained. Stability constants of the complexes were determined. It was shown...     

Evaluation Behavior for the Adsorptive of Ca(II) and Mg(II) Ions (Hardness of Water) from Water by Modified Copper Based on Metal Organic Frameworks and Potentiometric Sensors

Russian Journal of Electrochemistry - This study presents adsorption of Ca(II) and Mg(II) ions from water at different concentration. This causes problems such as corrosion and scaling....     

Reaction of arylthallium (III) compounds with Copper (II) and (I) cyanides. Synthesis of aryl cyanide

Various kinds of arylthallium(III) salts react with copper (II) or (I) cyanide in acetonitrile or pyridine to give the corresponding aryl cyanides in good yield. In acrylonitrile the reaction using copper(I) cyanide was revealed to be of an ionic concerted intermolecular and not radical type.     

Sorption of Copper(II) Ions with Nanosized Magnesium Phosphate

A new approach to the preparation of a nanosized sorbent based on magnesium phosphate has been developed. The patterns of copper(II) ions sorption with nanosized magnesium phosphate from aqueous solutions have been investigated. The sorption parameters have been determined, and the kinetics and mechanism of the processes have been elucidated. The high sorption ability of the nanoscale sorbent has been shown in comparison with existing sorbents based on magnesium phosphate.     

Complex Formation of Copper(II) Ions with Galactaric Acid

Complex formation of copper(II) ions with the galactarate ion [Gala]^{2 -} in aqueous solution was studied by means of potentiometric titration. Stability constants of the [CuGala] and [Cu(Gala)₂]^{2 -} complexes were determined. A complex compound was synthesized electrochemically and isolated from a DMSO solution containing a copper(II) salt and galactaric acid, and its composition was determined. The structure of the complex was determined by ESR.     

Complexation of Arabinogalactan with Copper(II) Ions in Aqueous Solutions

Complexation of Cu(II) with arabinogalactan as influenced by solution pH was studied by spectrophotometry and the method of dialysis equilibrium. Copper ions form complexes with arabinogalactan in a wide pH range, pH 5.0-12.5. Arabinogalactan forms two complex species with the metal. The composition and formation constant of the complex formed at pH <10.8 were determined.     

Metal complexes of carbazic acids,part 2. Copper(II) complexes ofN-substituted carbazic acids

Summary Copper(II) complexes of N-substituted carhazic acids have been prepared and characterised by analytical, magnetic. electronic and i.r. spectral measurements. The complexes, which are of two types, CuL₂(H₂O), (where L = carhazic acid. methy1carbazic acid and phenylcarbazic acid) and CuL, (where L = 2,3-dimethylcarbazic acid, 3.3-dimethvlcarbazic acid and 3.3-methylphenylcarbazic acid), have distorted octahedral structures, bonded through one of the nitrogen atoms and carboxylate group.     

On the Reaction of Triphenyltrithiophosphites with Copper (I) and Copper(II) Halides

Abstract

Reactions of triphenyltrithiophosphite (PhS)₃P with copper (I) and copper (II) halides (CuHal, CuHal₂, where Hal=Cl, Br) have been investigated.     

Synthesis and Crystal Structure of a Copper(II) Complex with 2,4-Dihydroxybenzylidene Benzoylhydrazone Ligand

1 INTRODUCTION The chemical properties of acylhydrazones Schiff bases and their complexes with some transition metal ions have been intensively investigated in several re- search areas because of their chelating capability and pharmacological applications[1～10]. Intriguingly, the copper(II) complexes are shown to be signifycantly more potent than the metal free chelate, suggesting that the metal complex is the biologically active species. Owing to the biological interest in these types …     

Solvation of Copper(II) Ions in Liquid Ammonia

X-ray absorption fine structure (XAFS) measurements have been performed at -50 degrees C on a 0.4 mol dm(-)(3) copper(II) nitrate solution in liquid ammonia. Extended X-ray absorption fine structure (EXAFS) spectroscopy was used to determine the coordination number and bond distances for the solvated copper(II) ion in solution. The equatorial ammonia nitrogens are located 2.00 ? from the copper and the axial nitrogen 2.19 ? from the copper. However, it was not possible from the EXAFS analysis alone to conclude whether there was one or two axial nitrogens. Therefore, X-ray absorption near-edge structure (XANES) spectroscopy was combined with discrete variational Xalpha (DV-Xalpha) molecular orbital calculations for a series of five- and six-coordinated models to determine the coordination number and the geometry. The experimental XANES spectrum was best reproduced by a model where the copper(II) ion is pentacoordinated in liquid ammonia in a square pyramidal geometry with the copper(II) ion lifted above the average nitrogen plane.     

Metal Exchange Reaction of Cd(II) 5,10,15,20-Tetra(4-chlorophenyl)porphyrinate with Copper and Zinc Chlorides in DMSO

Russian Journal of General Chemistry - The metal exchange reactions of Cd(II) 5,10,15,20-tetra(4-chlorophenyl)porphyrinate with CuCl2 and ZnCl2 in DMSO were studied by the spectrophotometric...     

Complex Formation by Galacturonic Acid with Copper(II) and Neodymium(III) Ions in Water Solution

Complex formation by galacturonic acid with copper(II) ion in water solution is studied by themethods of EPR spectroscopy. At the pH > 3 the EPR signal (g 2.174) confirms the complex formation at theligand carboxylic group. The following complex formation parameters are measured: equilibrium constant'g factor, hyperfine coupling constant, average complex lifetime. From the data of electron spectra invisible region the complex composition and stability constant is defined for copper(II) and neodymium(III).     

无溶剂条件下Yb(OTf)3催化的亚甲基化合物和醛的Knoevenagel反应

在Yb(OTf)₃催化下, 不用任何溶剂, 将活泼亚甲基化合物和各类醛进行Knoevenagel反应, 得到相应的取代烯烃衍生物. 此法操作简便, 对环境友好, 具有很高的反应产率, 且副产物少; 此外, 催化剂能够在进行反复回收利用之后仍然保持很高的催化活性.     

铜（II）离子对脱镁叶绿素-a荧光猝灭的研究

本文介绍了一种利用荧光熄灭定量的测定铜（II）的新方法。从新鲜菠菜中提取叶绿素-a,用高氯酸溶液处理,制得脱镁叶绿素-a。测量脱镁叶绿素-a的紫外-可见吸收光谱,观测到505和535nm处有特征吸收峰。在60 ℃水浴中,脱镁叶绿素-a的丙酮溶液与铜（II）离子水溶液混合,5分钟后发现混合液颜色变绿,505和535 nm处吸收峰消失。铜（II）离子水溶液与脱镁叶绿素-a的丙酮溶液混合后发生荧光猝灭现象,而类似浓度的其它生理离子在相同反应条件下对脱镁叶绿素-a的荧光猝灭现象不明显。 研究了铜（II）离子与脱镁叶绿素-a的反应时间,反应温度对荧光强度衰减的影响。并通过阿累尼乌斯经验关系估算铜（II）离子与脱镁叶绿素-a反应的活化能约为10 ±1kJ·mol-1。研究了铜（II）离子的浓度对脱镁叶绿素-a的丙酮溶液荧光强度的影响,在8.0×10-5 ～8.0×10-7 mol·dm-3范围内,铜（II）离子的浓度与混合液的荧光强度成线性衰减关系,检测限可达8.0×10-7 mol·dm-3。利用脱镁叶绿素-a的丙酮溶液的荧光强度变化测量,有望发展成为一种检测铜（II）离子的新方法。     

Reaction of Bioflavonoids with Copper(II) Acetate in Aqueous Solution

The reaction of dihydroquercetin, quercetin, and rutin with Cu(II) acetate in aqueous solution is studied. Quercetin and dihydroquercetin form complexes with Cu. The water-insoluble complexes are characterized as chelates of the 3,4-positions of the main -pyrone ring. Electronic spectroscopy showed the presence of stable polynuclear rutin complexes of composition rutin :Cu = 1:x, where x > 2.     

Organic Ion Exchangers. Synthesis and Their Behaviour in the Retention of Some Metal Ions

Summary: Three pyridine strong base anion exchangers as beads were obtained by quaternization reactions of a 4-vinylpyridine : 8% divinylbenzene copolymer of gel type. These resins possess methyl / ethyl / butyl radicals as substituents on N⁺ atoms and have exchange capacities of 4.80 mEq/g and 2.10 mEq/mL. For pyridine strong base anion exchangers, the behaviours in the retention processes of Cr(VI) as oxyanions and Ga(III) as [GaCl₄]⁻ complex anion were evaluated with the bath method. All the resins exhibited retention properties, but the retained amounts of the metal cations are different as a function of the alkyl length as substituent on N⁺ atoms and the complex anion nature. Thus, Cr(VI) oxyanions are best retained by the resin with  CH₃ as substituent on N⁺ atoms while [GaCl₄]⁻ complex anion by the resin with  C₄H₉ as substituent on N⁺ atoms. By aminolysis reaction of an ethylacrylate : acrylonitrile : divinylbenzene copolymer as beads of macroporous type with NH₂OH · HCl in the presence of C₂H₅OH a new chelating ion exchanger was performed which contains both amidoxime and hydroxamic acid functional groups. This ion exchanger has the retention property for different metal cations but its retention capacities values are strongly dependent of the nature of metal cation and the counterion as well as pH of the solution. Thus, in the static conditions Zn(II) cation with NOequation/tex2gif-stack-1.gif anion as counterion is retained with the best result at pH = 5. As an example, for the aqueous metal cation solution of 10⁻² M concentration for Zn(NO₃)₂ the resin possess at equilibrium a retention capacity of 6.70 mmol Zn/g dry resin and for Cu(II) from Cu(NO₃)₂ solution of same concentration, the retention capacity is 0.22 mmol Cu/g dry resin and Fe(III) from Fe(NO₃)₃ solution is not retained.