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Chwastowska J  Kosiarska E 《Talanta》1988,35(6):439-442
A chelating sorbent loaded with dithizone was obtained by chemical reaction with styrene-DVB (5%) copolymer as matrix. The analytical characteristics of the sorbent were established and optimum sorption conditions for Ag, Cu, Cd, Pb, Ni, Co and Zn under static and dynamic conditions determined. The sorbent was applied to determination of copper and lead in river water and of silver in electrolytic copper. After separation of traces of metals on the sorbent and desorption with hydrochloric acid, the metals were determined in the effluent by atomic-absorption spectrophotometry.  相似文献   

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(1S,3S)-1,3-二苯基-1,3-丙二胺的合成   总被引:1,自引:1,他引:0  
以二氯甲烷作溶剂,N-Boc保护的二氢吡唑在六甲基磷酰胺存在下与苯基格氏试剂反应,比较大量地制备了对应的四氢吡唑(4);再由4合成消旋的1,3-二苯基-1,3-丙二胺(1,总收率35%);1经L-二苯甲酰酒石酸盐拆分制得光学纯的(1S,3S)-1,3-二苯基-1,3-丙二胺,其结构经1HNMR确证。  相似文献   

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Pathak R  Rao GN 《Talanta》1997,44(8):1447-1453
A poly[styrene-co-(divinylbenzene)] resin (XAD-4) functionalized with 1-hydrazinophthalazine ligand has been prepared and its analytical properties investigated. The pH dependence of sorption of metal ion on the resin has been determined for Cu(II), Ni(II), Co(II), Zn(II), Cd(II), Pb(II), Fe(III) and Cr(III). Trace amounts of these metal ions were quantitatively retained on the resin and recovered by eluting with 1 mol l(-1) hydrochloric acid. The resin was found to be selective for Fe(III) and its separation from other metal ions was carried out effectively. Metal ions concentrations were determined using AAS.  相似文献   

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A macroporous, cross-linked polyacrylonitrile copolymer was synthesized, the nitrile groups were converted to carboxylic acid by hydrolysis, and these carboxylic acid groups were treated with L-cysteine and 1,6-hexanediol (binding agent). Studies of the basic characteristics of this resin showed that it was highly selective for silver(I), mercury(II), gold(III) and platinum(IV) in aqueous acidic solution, the maximum capacities being 0.97, 0.65, 1.22 and 0.39 mmol g-1 of dry resin, respectively. These four metal ions can be separated from each other, or concentrated from very dilute solutions, on a short column of the resin. The effects of different acids and of various common metal ions are reported.  相似文献   

9.
Sugii A  Ogawa N  Katayama I  Hida T 《Talanta》1982,29(4):263-266
A polystyrene-based macroreticular resin containing phenylalanine groups has been prepared and its analytical properties have been investigated and compared with Dowex A-1. The phenylalanine resin shows high selectivity for mercury(II) and copper(II) in the pH region 2-3. The sorption behaviour of copper has been examined in detail, with the intention of using the resin analytically. The important characteristics of the resin are fast equilibration, high selectivity and small volume change between its hydrogen form and metal forms. These enable it to be applied for the rapid concentration of trace amounts of copper in the presence of large amounts of diverse metals. It may be used for the determination of copper in sea-water and the separation of copper/cobalt and copper/nickel.  相似文献   

10.
Dev K  Rao GN 《Talanta》1995,42(4):591-596
A polystyrene divinyl benzene based resin containing bicine groups has been prepared and its analytical properties investigated. The pH dependence of sorption of metal on the resin has been determined for Cu(II), Fe(II), Ni(II), Co(II), Zn(II), Hg(II) and Pb(II). The important characteristics of the resin are fast equilibrium, high selectivity and small volume change between its hydrogen and metal forms. These enable it to be applied to the rapid concentration of trace amounts of these metal ions. It shows promise for the separation of lead from other metal ions.  相似文献   

11.
Reactions of 1,3-dihydroxyadamantane with 1,3-dicarbonyl compounds in the presence of 5 mol % of In(OTf)3 afforded a series of (1,3-adamantylene)bis-1,3-dicarbonyl compounds in yields of 25–83%.  相似文献   

12.
合成了标题Schiff碱并获得了其单晶,化学式为射线单晶衍射分析,该晶体属于单斜晶系,空间群P21/c,晶胞参数:可观测衍射点数1014个。晶体中分子以氢键结合形成二聚体。  相似文献   

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A novel chelating resin containing S, N and O atoms (PSME-EDA) was synthesized by using poly(2-hydroxyethylmercaptomethylstyrene) (PSME) and diethanolamine (EDA) as materials. Its structure was characterized by elemental analysis, Fourier transform-infrared spectra (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The adsorption of the resin for Hg2+ was investigated. The saturated adsorption capacity of PSME-EDA for Hg2+ could reach to about 1.1 mmol/g at 25 °C when the initial Hg2+ concentration was 0.02 mol/l. Some factors affecting the adsorption such as temperature, reaction time and ion concentration were also studied. The results showed that adsorption was controlled by liquid film diffusion. The increasing of temperature was beneficial to adsorption. The Langmuir model was better than the Freundlich model to describe the isothermal process. The values of ΔG, ΔH, and ΔS calculated at 25 °C were −7.99 kJ mol−1, 22.5 kJ mol−1 and 34.4 J mol−1 K−1, respectively. The adsorption mechanism of PSME-EDA resin for Hg(II) was confirmed by X-ray photoelectron spectroscopy (XPS).  相似文献   

14.
Chelating neutral (N,O) and cationic (N,N) first- and second-generation ruthenium(II) arene metallodendrimers based on poly(propyleneimine) dendrimer scaffolds were obtained from dinuclear arene ruthenium precursors by reactions with salicylaldimine and iminopyridyl dendritic ligands, respectively. The N,N cationic complexes were isolated as hexafluorophosphate salts and were characterised by NMR and IR spectroscopy, and MALDI-TOF mass spectrometry. Related mononuclear complexes were obtained in a similar manner and their molecular structures have been determined by X-ray diffraction analysis. The cytotoxicities of the mono- and multinuclear complexes were established using A2780 and A2780cisR human ovarian carcinoma cancer cell lines.  相似文献   

15.
Sugii A  Ogawa N  Hagiwara Y 《Talanta》1984,31(12):1079-1082
A macroreticular poly(acrylic acid)-based resin with triazolethiol as the functional group has been synthesized. The stability of the resin in acidic media and the behaviour in sorption and desorption of various metal ions have been investigated and compared with those of the acylthiosemicarbazide resin which is an intermediate in synthesis of the triazolethiol resin. Both resins show high affinity for copper(II) silver, cadmium and mercury(II), and high selectivity for silver and mercury(II) at low pH (1–2), and even at pH 7 if EDTA is present. The triazolethiol resin sorbs metal ions faster than the acylthiosemicarbazide resin does and sorbs mercury(II) from high concentrations of acids and neutral salt solutions. This resin has been applied to the concentration of silver and mercury(II) from sea-water samples by column operation.  相似文献   

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In this contribution, we report the synthesis, the chemical and photophysical characterization, and the study of the reactivity toward electrophiles of two mononuclear complexes of the type [Ru(bpy)2L]+ (bpy is 2,2'-bipyridyl), in which L is represented by the deprotonated form of 2-(1,H-tetrazol-5-yl)pyridine (L1) or 2-(1,H-tetrazol-5-yl)pyrazine (L2). The 1H and 13C NMR experiments that were performed on complexes RuL1 and RuL2 allowed us to establish that the tetrazolate moiety is bonded to the metal center via the N-1 nitrogen, while the coplanar arrangement adopted by the coordinated ligand upon coordination and the consequent interannular conjugation effect accounts for the unexpectedly low field resonance of the tetrazole carbon. The 13C NMR spectroscopy is also of fundamental importance to determine the chemo- and regioselectivity of the addition of a methyl group to RuL1 and RuL2, which takes place at the N-3 nitrogen of the five-membered ring. All these features were confirmed by the X-ray diffraction structures of RuL1 and of the methylated compounds RuL1Me and RuL2Me. Relative to these latter complexes, the presence of a methyl moiety does not cause any distortion from coplanarity of the coordinated tetrazolates. The redox properties of the complexes were investigated by cyclic voltammetry and indicated a quite different behavior between the pyrazinyl-tetrazolate and the pyridyl-tetrazolate complexes as the consequence of the higher electron-withdrawing character of the pyrazine ring. The study of the photophysical properties of the complexes also shows a significant diversity between the luminescent RuL1 and the rather poorly emissive RuL2. Interestingly, the methylated compounds RuL1Me and RuL2Me display radiative excited-state decays with longer lifetimes than their precursors; this feature indicates that methylation is a useful reaction for the tuning of the light emission performances of similar tetrazolate complexes. The synthesis and the characterization of a novel dinuclear complex of type [(bpy)2Ru-L3-Ru(bpy)2]2+, Ru(L3)Ru, where L3 is the bis-anion derived from bis-2,3-(1,H-tetrazol-5-yl)pyrazine, is also reported.  相似文献   

19.
《Polyhedron》2000,19(28):2689-2695
The reaction of an ethanolic solution of copper(II) pyridinecarboxylates CuX2·nH2O (where X is nicotinate (nic) (n=0) or isonicotinate (isonic) (n=4)) with ethylenediamine (en) in a molar ratio of 1:2 lead to the isolation of solid tetragonally distorted octahedral complexes of the type [Cu(en)2(H2O)2]X2·nH2O (n=1 for nic; n=0 for isonic). The analogous reaction of CuX2·nH2O with diethylenetriamine (dien) in a molar ratio of 1:1 leads to the formation of square-pyramidal pentacoordinated complexes of the type [CuX(dien)(H2O)]X. On the other hand, the reaction of equimolar quantities of copper(II) nitrate and dien with nicotinate anions (equimolar quantities of pyridinecarboxylic acid and NaOH) in ethanolic solutions gives a solid monomeric complex [Cu(nic)(NO3)dien)(H2O)]·H2O in which the coordination polyhedron around the Cu(II) atom is a (4+1+1) distorted tetragonal bipyramid. Based on the molecular structure the electronic and IR spectra are discussed. Moreover, the results of the quantitative determination of antimicrobial activity of the isonic complexes [Cu(isonic)2(H2O)4], [Cu(en)2(H2O)2](isonic)2, [Cu(isonic)(dien)(H2O)](isonic), as well as isonicotinic acid, ethylenediamine and diethylenetriamine alone are discussed.  相似文献   

20.
《Polyhedron》2001,20(15-16):1867-1874
The synthesis and characterization of [Cu2(2-MeSnic)4(H2O)2], [Cu(2-MeSnic)2(en)], [Cu(en)2(H2O)2](2-MeSnic)2 and [Cu(dien)(H2O)2](2-MeSnic)2 (where 2-MeSnic=2-methylthionicotinate, en=ethylenediamine, dien=diethylenetriamine) is reported. The characterizations were based on elemental analysis, infrared, electronic and EPR spectra, and magnetic susceptibility measurements over a temperature range of 1.9–300 K. The available evidence supports a dimeric structure for [Cu2(2-MeSnic)4(H2O)2] and for [Cu(en)2(H2O)2](2-MeSnic)2 a tetragonal-bipyramidal environment about the copper(II) atom. The other two complexes were studied also by X-ray analysis. The [Cu(dien)(H2O)2](2-MeSnic)2 crystallizes in the monoclinic system. The copper(II) atom has a square-pyramidal arrangement, with three nitrogen atoms of the tridentate diethylenetriamine and one water molecule in the base of the pyramid, and the remaining water molecule occupies the apical position. The copper(II) atom deviates from the basal plane by 0.1164(5) Å toward the water molecule in the apical position. The copper(II) atom in [Cu(2-MeSnic)2(en)] is coordinated by two symmetry-dependent nitrogen atoms of ethylenediamine and by two pairs of non-equivalently coordinated carboxyl oxygen atoms of two symmetry-dependent 2-methylthionicotinates with CuO bond distances of 1.975(2) and 2.564(2) Å, respectively, resulting in a highly distorted tetragonal-bipyramidal coordination.  相似文献   

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