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[en] Complete text of publication follows. Quantitative indication of the process of forming a complex comes from the evaluation of the stability constants of formation constant, which characterize the equilibria corresponding to the successive addition of ligands. Paper Electrophoretic Technique is described for the study of beryllium(II) and cobalt(II) biologically significant binary complexes with sarcosine. The stability constants of ML and ML2 complex species of Be(II) / Co(II) - sarcosine have been found to be (6.17 ± 0.09, 7.06 ± 0.04) and (4.27 ± 0.07, 2.98 ± 0.11) (logarithm stability constant values), respectively at ionic strength 0.1 Mol L-1 and a temperature of 35 deg C.
[en] Results are given for experimental determination of cobalt oxides solubility and of cobalt ions hydrolysis constants in diluted water solutions of KOH with pH value in interval of 8 - 14 and at the temperature up to 3000C. Method of the experiment and results obtained are stated. Data are given of CaO solubility depending on temperature and pH of solution and also data of different forms of cobalt correlation depending on temperature of solution. Equilibrium constants are given for reaction in the system CaO-K2O-H2O in the temperature interval of 25 - 3000C.(I.T.)
[en] A recently reported NMR method for the measurement of deuterium equilibrium isotope effects is applied to the hydration of the paramagnetic cobalt(II) ion. An isotope effect of about 1.3% is measured. A substantial difference between the intrinsic shift of H2O and D2O when coordinated to cobalt is also measured
[en] A methoxyphenylcycl[3,2,2]azine derivative (MPC) was synthesized and its function as a fluorescent probe for metal ions was investigated. Studies revealed that the fluorescence intensity of cycl[3.2.2]azine derivative varies with the concentration of Co2+ ion. The sensor was highly selective towards Co2+ ion over other metal ions and was found to be sensitive towards Co2+ ion with a detection limit of 2.85×10−3 M. A linear concentration range from 2.30×10−2 M to 4.76×10−3 M was obtained. Furthermore the sensor could be utilized for the determination of Co2+ in pharmaceutical samples.
[en] The oxygen parameters in the unit cells of Znsub(0.8) Cosub(0.2) Fe2O4 and Znsub(0.95) Cosub(0.05) Fe2O4 were refined on a computer using neutron diffraction data taken at 2930K. It was found that Zn enters the tetrahedral sites only. A careful examination for the distribution of Co2+ ion in the studied samples suggests that Co2+ ions have no preference for either site
[en] The adsorption of Co(II) by well characterized China clay in pH range (3.0-6.5) at various temperatures followed the Langmuir isotherms. Co(II) removal is favoured by low concentration, low temperature and low pH. The high adsorption at low pH is attributed to the content of silica in China clay. (author)
[en] In order to predict the dynamic behaviors of uranium and cobalt in a fixed bed at various influent pH values of liquid waste, the adsorption system is regarded as a multi-component adsorption between each ionic species in the solution. Langmuir isotherm parameters of each species were extracted by incorporating equilibrium data with the solution chemistry of the uranium and cobalt using IAST. Prediction results were in good agreement with the experimental data, except for a high concentration and pH. Although there was some limitations in predicting the cobalt adsorption, this method may be useful in analyzing a complex adsorption system where various kinds of ionic species exist in a solution.
[en] The employment of linear di-, tri-, and tetra-ammoniums has generated a hierarchy in the binodal (412⋅63)(49⋅66)n topologies with n = 1, 2, and 3, respectively, for the cobalt formate frameworks with increasing length of the cavities to match the ammoniums. This indicates the length-directing effect of the polyammoniums. The dynamic movements of polyammoniums between favored sites or orientations within the cavities lead to slow dielectric relaxations. All materials are spin-canted antiferromagnets in low temperatures and show reduced spontaneous magnetizations from di- and tri-, to tetra-ammoniums, because of the increased number of unique Co ions or the antiferromagnetically coupled sublattices