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1.
In a search for environmental-friendly metal chelating ligands for industrial applications, the protonation and complex formation equilibria of 3-hydroxy-2,2′-iminodisuccinic acid with Mg2+, Ca2+, Mn2+, Fe3+, Fe2+, Co2+, Ni2+, Cu2+, and Zn2+ ions in aqueous 0.1 mol L?1 NaCl solution were studied at 25°C by potentiometric titration. The model for complexation and the stability constants of the different complexes were determined for each metal ion using the computer program SUPERQUAD. In all cases, complex formation was dominated by stable ML n ?4 complexes.  相似文献   

2.
Russian Chemical Bulletin - Heterometallic malonate complexes [Ag2Ni(H2O)2(R2mal)2]n (R2mal2– is the dimethylmalonate dianion (Me2mal2–) (1) or the cyclobutane-1,1-dicarboxylate dianion...  相似文献   

3.
By a matrix method of successive approximations, using perturbation theory, the complete set of force constants has been calculated for the free anions WO,2– and MoO4 2– and for systems MEO4 2–(M = Na2 +, Li2 +, Pb2+,Sr2+, Ca2+; E = W, Mo) on the basis of known frequencies of IR and Raman spectra of the corresponding individual melts. Analysis of the results indicates an increase in the force constants of E-O bond stretching and the bending force constants for AD- and MoO4 2– with increasing specific charge of the cation in a field of singly or doubly charged cations.Deceased.Poltava Engineering Construction Institute. Institute of General and Inorganic Chemistry, Academy of Sciences of the Ukrainian SSSR, Kiev. Translated from Teoreticheskuya i ÉksperimentaI'naya Khimiya, No. 1, pp. 120–123, January–February, 1991. Original article submitted January 12, 1989.  相似文献   

4.
The state of d-elements uranogermanates MII(HGeUO6)2·6H2O in aqueous salt solutions in a wide range of ionic strength, ionic composition, and acidity has been investigated. The pH ranges of the uranogermanates stability have been determined, and products of their transformation have been identified. Solubility, solubility equilibrium constant, and Gibbs energy of formation have been determined for the studied uranogermanates. Diagrams of uranium(VI), germanium(IV), and M(II) state in aqueous solutions and in equilibrium solid phases have been plotted.  相似文献   

5.
Complex rhodium(III) salts with the composition trans-M[Rh(NH3)2(NO2)4], where M = K+, Cs+, Ag+, and N(CH3) 4 + , are prepared and characterized. The molecular and crystal structures are determined by X-ray crystallography.  相似文献   

6.
The infrared and Raman spectra of Na2Cu(C2O4)(2)·2H2O, K2Cu(C2O4)(2)·2H2O and (NH4)2Cu(C2O4)(2)·2H2O were recorded and briefly discussed on the basis of their structural peculiarities and by comparison with the vibrational spectra of other metallic oxalates.  相似文献   

7.
介绍了描述25℃Li+,Na+,K+,Mg2+/Cl-,SO42--H2O体系的热力学Pitzer模型.给出了为获得Pitzer混合参数而测定的Li+/Cl-,SO42--H2O,Li+,K+/Cl--H2O,Li+,Na+/Cl--H2O等三元体系和Li+,Mg2+/Cl-,SO42--H2O四离子体系溶液的渗透系数.详细叙述如何利用热力学数据和溶解度数据,获得Li+,Mg2+/Cl-,SO42--H2O,Li+,K+/Cl-,SO42--H2O,Li+,Na+/Cl-,SO42--H2O体系全部混合参数及7种锂盐Gibbs标准生成自由能.进而通过数据对比,介绍了本模型在含Li+多组分溶液25℃热力学性质计算、含Li+多组分体系25℃溶解相平衡预测等方面的应用.  相似文献   

8.
The evaporation of a Tunisian brine sample involving the system Na+, Mg2+, K+, Cl, S 4 2– –H2O was studied under atmospheric pressure and at ambient temperature. The selective densities of precipitation of halite (NaCl) and of co-precipitation of halite and astrakanite (Na2Mg(SO4)2·4H2O), halite and kaïnite (MgSO4·KCl·H2O) and epsomite MgSO4·7H2O were determined.During the evaporation of the studied brine, calculations related to the hypothetical composition of the solution in terms of the simple salts NaCl, MgSO4, KCl and MgCl2.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

9.
10.
Uranyl silicates with formula MII(HSiUO6)2·6H2O (MII=Mn, Co, Ni, Cu, Zn) were investigated in aqueous solutions in the pH range of 0÷14. The pH interval was established where compounds preserve their composition and structure. It varies in the pH range of (3.5–4.0)÷(10.8–11.4) and depends on MII type. Out of this pH interval investigated uranyl silicates convert to the compounds of other composition and structure, such as amorphous silica, polyuranates and hydroxides of 3d-transition elements. The solubility of MII(HSiUO6)2·6H2O was determined, it’s value changes on the several orders of magnitude from 10?6 M in subalkali solutions to 10?3 M in acid and strongly alkaline media. Using obtained experimental data the solubility products and solubility curves of uranyl silicates were calculated by mathematical modeling. Also the speciation diagrams of uranium (VI), silicon (IV) and M (II) in solutions and solids were plotted.  相似文献   

11.
综述了近年来我们在多孔磁体甲酸盐系列[M3(HCOO)6](M=Mn2 ,Fe2 ,Co2 ,Ni2 ,Fe2 /Zn2 )获得的研究结果.这些多孔磁体可以在常温下用温和的溶液化学方法制备获得,它们的结构是以MM4四面体为节点的金刚石多孔骨架,呈现了很好的热稳定性、多孔性、广谱的客体包合性能和稳定性.由于客体的包合对多孔磁性骨架的结构参数产生影响以及客体和骨架之间的弱氢键相互作用,这些多孔磁体表现了丰富的和客体调控的磁性质.混合金属的多孔磁体[FexZn3-x(HCOO)6]表现了随着Zn2 的含量增加而发生的由三维磁有序到自旋玻璃、再到超顺磁体、最后到顺磁体的渐次转变.  相似文献   

12.
MMoO4 (M = Fe2+, Co2+, Ni2+) nanocrystaline particles with similar nanoscale particle size were synthesized by a salt aqueous solution reaction. UV–Vis absorbance spectra show that the nanoparticles are of good light absorbance in UV–Vis light region and narrow band gap. The variation in oxidation–reduction potential (ORP) of selected methyl orange aqueous solution due to the presence of the nanoparticles is measured in various conditions. The light absorption and the ORP determine the photodegradation rate of the aqueous methyl orange solution on the nanoparticles. The ORP is clearly also a necessary and useful parameter in research on and applications of the photocatalysis.  相似文献   

13.
The low frequency vibrational spectra (Raman and IR) of crystalline metaborates Ba2MII(B3O6)2 (MII  Mg, Ca, Ni, Co, Cd) are interpreted on the basis of a factor group analysis and with the help of 24Mg26Mg and 40Ca44Ca isotopic shifts. The far-IR spectra of the glasses appear as the envelope of the spectra of the corresponding crystalline compounds for MII  Mg, Ca and Cd, but they exhibit an additional broad absorption centred near 400 cm−1 for MII  Co, Ni and Zn. This absorption is assigned to a fourfold coordination of part of the MII cations, the remaining being in sixfold coordination (as in the crystal) and responsible for a broad absorption in the 300-200 cm−1 region. The possible existence of correlations between coordination and vibrational frequencies is discussed for either alkali and alkaline-earth cations, or transition elements.  相似文献   

14.
Russian Chemical Bulletin - A series of heterometallic 1D coordination polymers {[MII(VIVO)(Etmal)2(H2O)5] ? 2 H2O}n (MII = Mn (1), Co (2), Ni (3), Cd (4)) were synthesized. These compounds...  相似文献   

15.
The intramolecular proton transfer in cationized glycine and chlorine substituted derivatives with M = Na+, Mg2+, Ni+, Cu+, and Cu2+ has been studied with the three parameter B3LYP density functional method. The coordination of metal cations to the oxygens of the carboxylic group of glycine stabilizes the zwitterionic structure. For all monocations the intramolecular proton transfer occurs readily with small energy barriers (1-2 kcalmol(-1)). For the dication Mg2+ and Cu2+ systems, the zwitterionic structure becomes very stable. However, whereas for Mg2+, the proton transfer process takes place spontaneously, for Cu2+ the reaction occurs with an important energy barrier. The substitution of the hydrogens of the amino group by chlorine atoms decreases the basicity of nitrogen, which destabilizes the zwitterionic structure. For monosubstituted glycine complexed with Na+, the zwitterionic structure still exists as a minimum, but for disubstituted glycine no minimum appears for this structure. In contrast, for Mg2+ complexed to mono- and disubstituted glycine, the zwitterionic structure remains the only minimum, since the enhanced electrostatic interaction with the dication overcomes the destabilizing effect of the chlorine atoms.  相似文献   

16.
The title complexes were prepared and characterized employing spectral (FAB-Mass, IR, electronic, (1)H and (13)C NMR), thermal and electrochemical techniques. Analytical and FAB-Mass data suggested a homo-dinuclear stoichiometry. IR and electronic ligand field spectral studies coupled with molecular model computations have indicated a distorted octahedral geometry where the ligand coordinates as a hexadentate dianionic [H(3)DTPA](2-)(H(5)DTPA=diethylenetriaminepentaacetic acid) moiety. The electrochemical redox properties and the antibacterial activities of the compounds were also investigated.  相似文献   

17.
In a search for environmentally friendly metal-chelating ligands for industrial applications, the protonation and complex formation equilibria of iminodisuccinic acid (IDS) and 3-hydroxy-2,2′-iminodisuccinic acid (HIDS) with Cd2+, Hg2+, and Pb2+ in aqueous 0.1?mol?L?1 NaNO3 solution were studied at 25°C by potentiometric titration. Models for complexation and stability constants of the different complexes were determined for each metal ion using the computer program SUPERQUAD. In all cases, complex formation was dominated by stable ML2? complexes.  相似文献   

18.
Dicalcium phosphate dihydrate, DCPD (CaHPO4·2H2O), brushite, is an important calcium phosphate compound encountered in mineralized tissues and used in medicine, especially in bone cement formulations. However, the use of DCPD as direct implantable biomaterial has not received dedicated attention. In addition, the possibility to dope DCPD with biologically active ions to modulate its performances was not systematically explored. We have investigated in depth the doping of DCPD with Mg2+, Sr2+, Zn2+, Cu2+, and Ag+ ions. Clear modifications in terms of chemical composition, particle size, pore distribution, crystal morphology, and affinity for water were pointed out. Then, the samples were cultured with human adipose-derived stem cells to explore cytotoxicity and proliferation. Various behaviors were noticed dependent on the incorporated metal ions. Such DCPD compounds associated with bioactive metal ions, and particularly Ag+ and Zn2+, appear promising as a new family of reactive materials for use, as such or in combination, in bone-related applications.  相似文献   

19.
Journal of Sol-Gel Science and Technology - Manganese substituted cobalt ferrites (CoMn x Fe2?x O4, x?=?0.2, 0.4, 0.6, 0.8 and 1.0) synthesized using sol gel autocombustion method...  相似文献   

20.
The pK 2 * for the dissociation of sulfurous acid from I=0.5 to 6.0 molal at 25°C has been determined from emf measurements in NaCl solutions with added concentrations of NiCl2, CoCl2, McCl2 and CdCl2 (m=0.1). These experimental results have been treated using both the ion pairing and Pitzer's specific ion-interaction models. The Pitzer parameters for the interaction of M2+ with SO 3 2? yielded $$\begin{gathered} \beta _{NiSO_3 }^{(0)} = - 5.5, \beta _{NiSO_3 }^{(1)} = 5.8, and \beta _{NiSO_3 }^{(2)} = - 138 \hfill \\ \beta _{CoSO_3 }^{(0)} = - 12.3, \beta _{CoSO_3 }^{(1)} = 31.6, and \beta _{CoSO_3 }^{(2)} = - 562 \hfill \\ \beta _{MnSO_3 }^{(0)} = - 8.9, \beta _{MnSO_3 }^{(1)} = 18.7, and \beta _{MnSO_3 }^{(2)} = - 353 \hfill \\ \beta _{CdSO_3 }^{(0)} = - 7.2, \beta _{CdSO_3 }^{(1)} = 13.8, and \beta _{CdSO_3 }^{(2)} = - 489 \hfill \\ \end{gathered} $$ The calculated values of pK 2 * using Pitzer's equations reproduce the measured values to within ±0.01 pK units. The ion pairing model yielded $$\begin{gathered} logK_{NiSO_3 } = 2.88 and log\gamma _{NiSO_3 } = 0.111 \hfill \\ logK_{CoSO_3 } = 3.08 and log\gamma _{CoSO_3 } = 0.051 \hfill \\ logK_{MnSO_3 } = 3.00 and log\gamma _{MnSO_3 } = 0.041 \hfill \\ logK_{CdSO_3 } = 3.29 and log\gamma _{CdSO_3 } = 0.171 \hfill \\ \end{gathered} $$ for the formation of the complex MSO3. The stability constants for the formation of MSO3 complexes were found to correlate with the literature values for the formation of MSO4 complexes.  相似文献   

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