scholarly journals Theoretical description of the ligand function for ionoselective electrodes reversible to metal anion complexes. 2. Selectivity to foreign ions

2020 ◽  
pp. 29-42
Author(s):  
Vladimir V. Egorov ◽  
Andrei V. Semenov ◽  
Andrei D. Novakovskii ◽  
Yauhen B. Akayeu
Keyword(s):  
Ammonium Thiocyanate ◽  
Thermodynamic Characteristics ◽  
Zinc Ion ◽  
Ion Exchanger ◽  
Sample Solution ◽  
Background Concentration ◽  
Zinc Ions ◽  
Selective Electrode ◽  
Foreign Ions ◽  
Diffusion Parameters

Within the framework of the steady-state diffusion model, the equations have been obtained explicitly describing the selective electrode selectivity coefficient to the ligand ion in relation to foreign ions not forming complexes with zinc ions, as a function of fundamental thermodynamic characteristics (exchange constants of tetrathiocyanatozincate for thiocyanate and foreign ion, concentrations of ion exchanger in the membrane and zinc ion in the sample solution), as well as controllable diffusion parameters (thicknesses of solution and membrane phase diffusion layers, governed by stirring mode and measuring time, respectively). Separate attention is given to cases of measurements in presence and in absence of constant background concentration of zinc ions in the sample solution. It has been shown that selectivity of tetrathiocyanatozincate selective electrode to thiocyanate ion in relation to anions not forming complexes with zinc, is several orders of magnitude higher than selectivity of an ordinary thiocyanate-selective electrode containing higher quaternary ammonium thiocyanate as an ion exchanger, and increases regularly with the background concentration of zinc ions. The results obtained are in general agreement with the experimental data given in the literature. It has been shown that variability of selectivity coefficients caused by variations of diffusion parameters within the limits corresponding to real measuring conditions, can be up to 0.3–0.4 orders of magnitude.

Microbial-Induced Mineralization of Zinc Ions Based on the Degradation of Toluene and Its Characterization

2021 ◽  
Vol 13 (4) ◽  
pp. 656-661
Author(s):  
Yiyan Lv ◽  
Qiwei Zhan ◽  
Xiaoniu Yu
Keyword(s):  
Particle Size ◽  
Phase Composition ◽  
Surface Morphology ◽  
Organic Compounds ◽  
Low Cost ◽  
Zinc Ion ◽  
Zinc Ions ◽  
Quick Response ◽  
Zinc Carbonate ◽  
Carbonate Ions

Microbial-induced degradation of aromatic organic compounds and mineralization of zinc ions have attracted much attention because of its low cost, simple operation and quick response. This research, toluene was decomposed and made the concentration of carbonate ions increased accordingly by the enzymatic pressing of microorganisms, meanwhile carbonate ions mineralized zinc ions into carbonate precipitations. The composition and microstructure were analyzed systematically. The analysis results indicated that carbonate precipitations, basic zinc carbonate, could be successfully prepared by microbial method. The particle size of basic zinc carbonate was nanometer, and its shape was near-spherical. Furthermore, the phase composition, functional groups and surface morphology of the precipitations prepared by different methods were basically the same. This work provided a new method for remediation of zinc ion pollution based on the degradation of toluene.

scholarly journals Removal of Zinc ions from industrial wastewater with wool fibers

2010 ◽  
Vol 7 (3) ◽  
pp. 1193-1201
Author(s):  
Baghdad Science Journal
Keyword(s):  
Acid Concentration ◽  
Contact Time ◽  
Industrial Wastewater ◽  
Metal Ion ◽  
Low Cost ◽  
Zinc Ion ◽  
Ion Concentration ◽  
Natural Material ◽  
Zinc Ions ◽  
Wool Fibers

In this research, the efficiency of low-cost unmodified wool fibers were used to remove zinc ion from industrial wastewater. Removal of zinc ion was achieved at 99.52% by using simple wool column. The experiment was carried out under varying conditions of (2h) contact time, metal ion concentration (50mg/l), wool fibers quantity to treated water (70g/l), pH(7) & acid concentration (0.05M). The aim of this method is to use a high sensitive, available & cheep natural material which applied successfully for industrial wastewater& synthetic water, where zinc ion concentration was reduced from (14.6mg/l) to (0.07mg/l) & consequently the hazardous effect of contamination was minimized.

Low-Temperature Electrothermal Vaporization of 8-Hydroxyquinolinate Complex for Determination of Trace Vanadium by ICP-AES

1996 ◽  
Vol 50 (6) ◽  
pp. 785-789 ◽  
Author(s):  
Shiquan Tao ◽  
Takahiro Kumamaru
Keyword(s):  
Low Temperature ◽  
Operating Conditions ◽  
Sample Introduction ◽  
Sample Solution ◽  
Heating Process ◽  
Electrothermal Vaporization ◽  
Foreign Ions ◽  
Relative Standard ◽  
Certified Values

A trace amount of vanadium was vaporized as 8-hydroxyquinolinate complex by using a low-temperature tungsten boat furnace for sample introduction in ICP-AES. Experimental results suggest that vanadium was vaporized as vanadium(III) 8-hydroxyquinolinate complex. Vanadium(V) and vanadium(IV) were reduced in the heating process before vaporization. The operating conditions were optimized, and the effects of foreign ions were investigated. The existence of tin(II) ion in sample solution was found to enhance the emission intensity of vanadium, improve the precision of the proposed method, and also suppress the interferences from other foreign ions. The detection limit in the presence of 5 μg tin(II) was determined to be 4 pg, and in the absence of tin(II), 7 pg, of vanadium. Sub-μg L−1 levels of vanadium in sample solution could be determined by the proposed method. The precisions in relative standard deviation (% RSD) for 100 pg of vanadium under the same conditions described above were 1.9% and 4.1%, respectively. The contents of vanadium in some standard steel and rock samples determined by the proposed method were in good agreement with their certified values.

Development of flow injection analysis-solid phase extraction based on ion imprinted polymeric nanoparticles as an efficient and selective technique for preconcentration of zinc ions from aqueous solution

2017 ◽  
Vol 41 (17) ◽  
pp. 8828-8836 ◽  
Author(s):  
Fereshteh Fereidoonipour ◽  
Hamid Reza Rajabi
Keyword(s):  
Solid Phase Extraction ◽  
Flow Injection ◽  
Flow Injection Analysis ◽  
Solid Phase ◽  
Polymeric Nanoparticles ◽  
Zinc Ion ◽  
Phase Extraction ◽  
Zinc Ions ◽  
Ion Imprinted ◽  
Separation And Preconcentration

Here, a new flow injection analysis-solid phase extraction (FIA-SPE) technique was developed by using zinc ion imprinted polymeric nanoparticles (Zn-IIP NPs) for the separation and preconcentration of Zn2+ions from aqueous solutions.

scholarly journals Zinc ion adsorption on carbon nanotubes in an aqueous solution

2012 ◽  
Vol 14 (3) ◽  
pp. 29-37 ◽  
Author(s):  
A. Ansari ◽  
M.A. Mehrabian ◽  
H. Hashemipour
Keyword(s):  
Carbon Nanotubes ◽  
Molecular Dynamics ◽  
Adsorption Process ◽  
Electrostatic Force ◽  
Zinc Ion ◽  
Dynamics Simulation ◽  
Ion Adsorption ◽  
Zinc Ions ◽  
Interaction Energies ◽  
Water Layers

The literature devoted to numerical investigation of adsorption of heavy metal ions on carbon nanotubes is scarce. In this paper molecular dynamics is used to simulate the adsorption process and to investigate the effect of the infl uencing parameters on the rate of adsorption. The predictions of the molecular dynamics simulation show that the adsorption process is improved with increasing the temperature, pH of solution, the mass of nanotubes, and surface modifi cation of CNT using hydroxyl and carboxyl functional groups. The results predicted by the model are compared with the experimental results available in the literature; the close agreement validates the accuracy of the predictions. This study reveals that the water layers around the carbon nanotubes and the interaction energies play important roles in the adsorption process. The study also shows that electrostatic force controls the attraction of zinc ions on the nanotube sidewall.

scholarly journals CHANGE IN THERMODYNAMIC CHARACTERISTICS OF HYDRATION OF CARBOXYL FIBER SORBENT IN EXCHANGE OF MAGNESIUM AND CALCIUM CATION

2020 ◽  
Vol 63 (4) ◽  
pp. 42-48
Author(s):  
Yuriy S. Peregudov ◽  
Sabukhi I. Niftaliev ◽  
Anna V. Timkova ◽  
Larisa P. Bondareva ◽  
Aleksey V. Astapov
Keyword(s):  
Ion Exchange ◽  
Gibbs Energy ◽  
Phase Transfer ◽  
Thermodynamic Characteristics ◽  
Ion Exchanger ◽  
Isopiestic Method ◽  
Ionic Form ◽  
Magnesium Ions ◽  
Calcium And Magnesium ◽  
Sodium Form

The relationship between the characteristics of hydration and the selectivity of the fibrous carboxyl sorbent is established. Using the isopiestic method and thermal analysis, the hydration of the carboxyl fiber ion exchanger VION KN-1 in sodium, calcium and magnesium forms was studied. The quantity of absorbed water was determined, including the ratio of kinetically unequal water in the sorbent phase. The amount of water absorbed form of magnesium ion exchanger is greater than calcium, the molar proportion of water distribution varying in the degree of hydration of the magnesium and calcium forms fibers substantially equally. The changes in Gibbs energy of hydration and enthalpy of dehydration of ion-exchange fiber are calculated. The increase in Gibbs energy is due to the absorption of near- hydration water, and water farthest hydration is adsorbed at a constant value of the energy. Its highest values are determined for the magnesium form of the sorbent, and the least-for calcium, which corresponds to the ratio of the absorbed solvent of both forms in the first step of hydration. The exchange isotherms of calcium and magnesium ions on the sodium form of VION KN-1 fiber were obtained. The Gibbs energy of solvent interface transfer was calculated, which represents the difference between the Gibbs energies of ion exchange sorption and the direct exchange of cations, and describes the contribution of the change in sorbent hydration during the transition from one ionic form to another. It is found that the selectivity of extractable fiber ion exchanger to metal cations depending on the change in the sorbent during the hydration of ion exchange, which is energetically favorable process and promotes ion-exchange sorption. Carboxyl cation exchanger is more selective for magnesium ions than calcium ions, as confirmed by phase transfer energy high values solvent and less water released during the transition from the sodium form to the magnesium than during the transition to the calcium.

scholarly journals Dinâmica Molecular Ab Initio da Complexarão de Íons zinco com a vitamina C em Fase Gasosa

2020 ◽  
Author(s):  
Wilson Roberto Lopes Filho ◽  
Yago F. Lopes ◽  
Lilian T. F. de M. Camargo ◽  
Ademir J. Camargo
Keyword(s):  
Molecular Dynamics ◽  
Vitamin C ◽  
Ab Initio ◽  
High Stability ◽  
Average Distance ◽  
Zinc Ion ◽  
Food Supplement ◽  
The Body ◽  
New Drugs ◽  
Zinc Ions

Zinc and vitamin C are essential micronutrients for the conservation of the human body, being essential for the maintenance of the immune system, reducing the risk, severity and duration of infectious diseases. They are taken together as a food supplement, resulting in the improvement of pneumonia and malaria infections. Vitamin C and zinc are also associated with measures of obesity and adiposity. Studies report that vitamin C complexed in zinc promotes adipogenesis and stimulates the generation of insulin-responsive adipocytes. Therefore, since vitamin C together with zinc are fundamental for the body, and that vitamin C complexed with zinc can promote adipogenesis and stimulate the generation of adipocytes responsive to insulin, the study of the interaction between these micronutrients will broaden the understanding of its bioactivity, which may be important in the study of a new use of vitamin C and zinc combined. Thus, it is intended to study the complexation of Vitamin C with the zinc ion using simulations of Molecular Dynamics ab initio. Through the results of the dynamics, it is found that zinc interacted significantly with 3 atoms of vitamin C, thus identifying the formation of a tridentate complex, since the average distances between the metal and these atoms were between 2.176 and 2.261 Å. A decrease in the free Helmholtz energy is perceived as the zinc approaches these atoms, up to a distance of high stability, which corresponds to the average distance of these interactions. It is also evident that the complexation energy is -220,64 Kcal/mol indicating that the complexation is energetically favorable and that the complex formed is stable. Therefore, the results obtained broadened the knowledge about the complexation of zinc ions with vitamin C, which will be of great importance for the understanding of its bioactivity and in the planning of new drugs.

scholarly journals The effects of zinc and magnesium ingestion on essential trace-element accumulation in the organs of white rats upon cadmium exposure

2020 ◽  
Vol 27 ◽  
pp. 00110
Author(s):  
Svetlana Nikolaevna Timofeeva ◽  
Ilnur Ravilevich Kadikov ◽  
Andrey Aleksandrovich Korchemkin ◽  
Iskander Foatovich Vafin
Keyword(s):  
Health And Safety ◽  
Toxic Metal ◽  
Wistar Rat ◽  
Zinc Ion ◽  
Essential Elements ◽  
Zinc Ions ◽  
Magnesium Ions ◽  
White Rats ◽  
Irreparable Harm ◽  
Iron And Zinc

Due to high athropogenic loads on the environment, issues surrounding public health and safety in consumable products are being raised with ever-increasing frequency. One toxic metal, whose consumption results in irreparable harm to the health of animals and human is cadmium. To antagonize such toxic effects to human health, magnesium and zinc are considered being essential elements and their combination effects warrant further studies. To this end, we developed a Wistar rat model to look at the combinatorial effects of cadmium with magnesium and zinc consumption on the accumulation of iron and zinc ions in kidney and liver tissues. Our findings suggested that exposure to cadmium ions reduced zinc ion levels in the liver and kidneys, reduced iron ions in the liver (but were increased in the kidneys), decreased magnesium ions in the kidneys but increased their levels within the liver. Moreover, while the consumption of magnesium and zinc ions individually, partially reduced the effects caused by cadmium consumption alone, the simultaneous consumption of zinc and magnesium ions proved to be significantly more effective.

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