Effect of Na+, Li+, Pb2+, Ba2+, Si2+, and Ca2+ cations on force constants of W-O and Mo-O bonds of WO4 2− and MoO4 2− anions in melts

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.     

Complexation of 3-hydroxy-2,2′-iminodisuccinic acid (HIDS) with Mg2+, Ca2+, Mn2+, Fe3+, Fe2+, Co2+, Ni2+, Cu2+, and Zn2+ ions in aqueous solution

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.     

Study of the state of uranoarsenates MII(AsUO6)2·nH2O(MII = Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Pb2+) in aqueous solutions

State of uranoarsenates M^II(AsUO₆)₂·nH₂O (M^II = Mn, Co, Ni, Cu, Zn, Cd, Pb) in aqueous solutions in a wide range of acidity (pH 0?C14) was studied. Acid-base boundaries of existence of the compounds were estimated, products of conversion were identified, and solubility of M^II(AsUO₆)₂·nH₂O was determined. On the basis of the obtained data the solubility products and Gibbs functions of formation of uranoarsenates, and the solubility curves were calculated, phase diagrams of uranium(VI) and arsenic(V) in solutions and in equilibrium solid phases were constructed with the use of the equilibrium thermodynamics technique.     

Gas phase intramolecular proton transfer in cationized glycine and chlorine substituted derivatives (M-Gly, M = Na+, Mg2+, Cu+, Ni+, and Cu2+): existence of Zwitterionic structures?

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.     

The pK 2 * for the dissociation of H2SO3 in NaCl solutions with added Ni2+, Co2+, Mn2+, and Cd2+ at 25°C

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.     

A novel magnetic biosorbent prepared using an oak shell waste material as an efficient adsorbent for consecutive removal of Pb2+, Ag+, Ba2+, Sr2+, and CrO42− from aqueous solutions

In this research, the performance of a new biosorbent prepared using low-cost oak shell waste materials for consecutive removal of particular cations and chromate anions from aqueous solutions was studied. The adsorbent impregnated with Pb²⁺, Ag⁺, Ba²⁺, and Sr²⁺ was used to remove chromate anions by the formation of an appropriate insoluble precipitate. The biosorbent was characterized by FTIR, XRD, SEM, TG-DTG, and VSM techniques. The adsorption capacities of 133.84, 53.12, 50.12, and 40.39 mg g^?1 were obtained for chromate for the samples containing Pb²⁺, Ag⁺, Ba²⁺, and Sr²⁺ cations, respectively. The chromate uptake was inversely proportional to the k_sp of the chromate precipitate and increased with the cation content of the adsorbent. The adsorption process was kinetically fast and the equilibrium was established within 10 min. The experimental data were analyzed by the Langmuir, Freundlich, Sips, and Redlich-Peterson isotherm models. The data were fitted to the Langmuir isotherm, indicating that chromate was adsorbed homogeneously on the adsorbent surface.     

Brushite (Ca,M)HPO4, 2H2O doping with bioactive ions (M = Mg2+, Sr2+, Zn2+, Cu2+, and Ag+): a new path to functional biomaterials?

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.     

高锰酸钾-鲁米诺反应体系中碱土金属离子Mg2+,Ca2+,Sr2+,Ba2+化学发光行为研究

将被认为没有化学发光活性的第二主族(碱土金属)离子Mg^2 ,Ca^2 ,Sr^2 ,Ba^2 溶液注入到已充分反应的高锰酸钾与鲁米诺混合液中时,又发生了新的化学发光反应,并检测到强的化学发光信号．在对有关反应的动力学性质、化学发光光谱、紫外可见光谱及其它一系列实验研究的基础上,提出了可能的化学发光反应机理．同时,优化了反应条件,评价了这一反应用于Mg^2 ,Ca^2 ,Sr^2 ,Ba^2 分析的可行性．     

多孔磁体甲酸盐[M3(HCOO)6](M=Mn2+,Fe2+,Co2+,Ni2+,Fe2+/Zn2+)的研究

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.     

Surface alkaline-acidic and photocatalytic properties of MMoO4 (M = Fe2+, Co2+, Ni2+) nanoparticles in different media conditions

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.     

Front Cover: Method development for the investigation of Mn2+/3+, Cu2+, Co2+, and Ni2+ with capillary electrophoresis hyphenated to inductively coupled plasma–mass spectrometry

The lifetime of lithium ion batteries (LIBs) decreases under continuous cycling due to various degradation processes, such as dissolution of transition metals (TMs) from the electrodes. Therefore, suitable methods to analyze the oxidation states of TMs are mandatory to better understand the dissolution mechanisms of TMs from positive and negative electrodes (LIBs). To investigate the dissolution of Mn²⁺ and Mn³⁺ in electrolytes of LIBs, a previously implemented capillary electrophoresis (CE) method with UV/Vis spectroscopy detection was further developed with the aim of higher sensitivities and additional detection of other dissolved divalent TMs such as Co²⁺, Ni²⁺, and Cu²⁺. Therefore, inductively coupled plasma–mass spectrometry was applied instead of UV/Vis for detection. This also allows the use of Ga³⁺ instead of the previously used Cu²⁺ as an internal standard, which solves the limitation of this method for cycled LIBs due to copper dissolution from the copper-based current collector. The CE buffer based on sodium diphosphate as complexing agent for the stabilization of Mn³⁺ and cetyltrimethylammonium bromide as dynamic capillary wall modifier was optimized in terms of concentrations and pH. Finally, both manganese species and Co²⁺, Ni²⁺, and Cu²⁺ could be analyzed within 15 min. With this improved method, the dissolution of TMs in LIBs for positive electrode materials such as LiNi_0.5Mn_1.5O₄ (LNMO) or LiNi_xCo_yMn_zO₂ (NCM, x + y + z = 1) can be studied in future in more detail.     

Impact of metal ions (Cr3+, Co2+, Ni2+, Cu2+ and Zn2+) substitution on the structural,magnetic and catalytic properties of substituted Co–Mn ferrites synthesized by sol–gel route

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...     

Complexation of iminodisuccinic acid (IDS) and 3-hydroxy-2,2′-iminodisuccinic acid (HIDS) with Cd2+, Hg2+, and Pb2+ in aqueous solution

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 ML^2? complexes.     

Li~+,Na~+,K~+,Mg~(2+)/Cl~-,SO_4~(2-)-H_2O体系Pitzer热力学模型

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.     

Ferrocene containing N-tosyl hydrazones as optical and electrochemical sensors for Hg2+, Cu2+ and F− ions

Ferrocene containing N-tosyl hydrazones as selective and sensitive optical and electrochemical chemosensors were synthesized and characterized by ¹H NMR, ¹³C NMR, ESI-MS and X-ray analysis. The cation and anion binding studies were carried out using various techniques including electrochemistry, UV–vis and ¹H NMR spectroscopy. Chemosensors 2a and 2b have shown excellent selective recognition toward Hg²⁺, Cu²⁺ and F^? through optical and electrochemical signals. The color of 2a and 2b in solution changed visibly from pale yellow to red upon addition of Hg²⁺ion, while the color of solution changed from pale yellow to yellow green upon addition of Cu²⁺, which can be easily detected by the naked eye.     

Spectral, thermal and electrochemical characterization of novel homo-dinuclear complexes [M2(H3DTPA)(H2O)6]Cl2·xH2O (M=Cr2+, Mn2+, Co2+, Ni2+ or Cu2+)

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.     

碱土金属离子(Mg2+,Ca2+,Ba2+)掺杂对长余辉荧光粉SrAl2O4:Eu2+,Dy3+发光性能的影响

采用高温固相法制备了碱土金属离子(Mg2 ,Ca2 ,Ba2 )掺杂的SrAl2O4:Eu2 ,Dy3 长余辉荧光粉.XRD谱分析表明,随着基质中掺人的碱土金属离子(Mg2 ,Ca2 ,Ba2 )浓度增加,基质晶格常数也随之发生变化.Mg2 ,Ca2 和Ba2 3种碱土离子在SrAl2O4中的固溶范围分别为40%,15%和30%.光谱分析则表明在固溶范围内随着掺杂Mg3 ,Ca2 和Ba2 浓度的增大,样品的发射峰值会在480～530 nm范围出现规律性移动.适当浓度的Mg2 ,Ba2 掺杂会不同程度地提高样品的发光强度,而Ca2 的掺杂则会降低发光强度.但是碱土金属离子(Mg2 ,Ca2 ,Ba2 )的掺杂并不能延长SrAl2O4:Eu2 ,Dy3 荧光粉的余辉时间.