Aqueous Solutions Of Zinc Sulfate Research Articles

Preparation of nano zinc borate and investigation of flame-retardancy of ternary combination nano zinc borate/red phosphorus/expandable graphite on HDPE

Nano zinc borates were successfully synthesised from aqueous solutions of zinc sulfate, boric acid, and sodium hydroxide via the precipitation method. The effects of pH, temperature, and surfactants on the structure and morphologies of nano zinc borates were investigated. The nano zinc borates obtained at the pH of 7 to 8 were well-crystallised monophase Zn[B3O4(OH)3]. The morphologies of nano zinc borates were highly impacted by the reaction temperature and the surfactants. At the range of temperatures from 70 to 80oC, the nano zinc borates were nanoplates of 40-50 nm in thickness. The nano zinc borates grew out of the surface to form nanorods at 90oC and nanowhiskers at 100oC. The nano zinc borates modified with surfactants tended to form larger and thinner plate-like nanoparticles. In the presence of Tween 80, petal-like nano zinc borates were achieved. The petal-like nano zinc borates showed good flame retardant synergistic effects with red phosphorus and expandable graphite on high-density polyethylene matrix. Additionally, the nano zinc borates nanopetals significantly improved the mechanical properties of red phosphorus/expandable graphite/high-density polyethylene composites.

Ion hydration and association in aqueous solutions of zinc sulfate by dielectric spectroscopy

Aqueous solutions of zinc sulfate, ZnSO4(aq), have been studied at 25°C by dielectric relaxation spectroscopy (DRS) over the frequency range 0.2≤ν/GHz≤89 at concentrations 0.04≲c/mol L−1≲2.4. The spectra obtained could be accounted for mostly by the presence of four Debye processes (a 4D model). These processes consisted of two solvent-related modes at higher frequencies plus two solute-related modes at lower frequencies. At low solute concentrations (c≤0.34molL−1) it was necessary to include an additional small amplitude mode which was thought to be due to ion-cloud relaxation (a (D) + 4D model). While the DR spectra for ZnSO4(aq) were broadly similar to those of other divalent metal sulfate solutions there were also differences. In particular, no evidence was found for the significant formation of double-solvent-separated ion pairs (2SIP). Further, the mode centered around 8 GHz, which for similar systems is usually assigned to the presence of contact ion pairs (CIPs), appears to be an unresolved mixture of contributions from CIPs and dynamically-retarded (‘slow’) water molecules. Analysis of the solvent-related modes indicated that the free ions (Zn2+(aq) and SO42−(aq)) and the ion pairs (SIPs and CIPs) were strongly hydrated. The decline in their effective hydration numbers (Z values) with increasing c is common and is thought to result from ion/IP interactions. The overall association constant for the ion pairs was found to be consistent with literature data.

Synthesis of KZnF\(_{3}\) Phosphors by Co-Precipitation Method

Synthesis of KZnF\({}_{3}\) is rather tedious. Typical problems of fluoride synthesis are faced with more acuteness. Even in wet chemical preparations, use of hygroscopic starting materials like zinc chloride or nitrate presents considerable difficulties. A simple precipitation synthesis of KZnF\({}_{3}\) with aqueous solutions of zinc sulfate and potassium fluoride is described. Precipitation at the room temperature produces the compound profoundly contaminated with hydroxide phase. Phase pure compound is obtained when boiling solutions are mixed. Activators Cerium and europium could be incorporated by adding the corresponding sulfates to zinc sulfate solution during the precipitation. As prepared phosphor exhibited typical Ce\({}^{3+}\) luminescence. For obtaining Eu\({}^{2+}\) luminescence, the phosphor had to be given reducing treatment.

Development and Validation of Method for the Quantitative Determination of Zinc in its Chelate Complexes Using Energy Dispersive X-ray Fluorescence Spectroscopy

Introduction. The production, standardization and quality control process of various dietary supplements containing chelated zinc requires validated quantitative assessment methods. In this work, we propose an X-ray fluorescence spectroscopy (XRF) technique for determining the zinc content in the composition of coordination compounds using the example of a synthesized chelate complex with methionine.Aim. To synthesize Zn(Met)2 chelate complex, to develop and validate a method for its quantitative analysis using the XRF method.Materials and methods. The synthesized zinc chelate complex was investigated by IR spectroscopy. The XRF method was used to develop a method for quantifying the zinc content in the synthesized complex. We used dry mixtures of zinc sulfate monohydrate and L-methionine (Met) in a molar ratio of Zn to Met – 1 : 1, 1 : 2, 1 : 4, 1 : 8 and 1 : 16 and also aqueous solutions of zinc sulfate and L-methionine in a molar ratio of Zn to Met 1 : 2 with Zn concentrations from 0.5 to 100 mmol/l as calibration standards. Complexometric titration was used as an arbitration method for the quantitative determination of zinc content in the samples under study.Results and discussion. The IR spectrum of chelate complex confirmed the presence of a donor-acceptor bond between Zn2+ and the nitrogen atom of amino group in methionine. The titration results showed chelate compounds have a composition corresponding to the stoichiometric formula Zn(Met)2. XRF analysis of dry standard mixed samples demonstrated the presence of matrix effect, that makes impossible an accurate assessment of zinc content in the chelate compound. According to the XRF spectra of aqueous solutions containing zinc sulfate and methionine in a ratio of 1 : 2 at a zinc concentration of 0.5; 1; 2; 3; 4; 5; 10; 25; 50 and 100 mmol/L, a calibration graph was constructed – the dependence of the fluorescence signal intensity for the Kα line of zinc on the concentration of zinc in the solution (r = 0.9996). The method was evaluated by the following validation parameters: specificity, linearity, correctness, precision, and analytical range. The specificity of the validated method was proven in the presence of copper, iron, and silver.Conclusion. The developed method make it possible to determine with sufficient precision and correctness the content of Zn2+ in its aqueous solutions of inorganic and organic nature by the XRF method in the concentration range from 3 to 100 mmol/l without the influence of the matrix.

Properties of Langmuir and immobilized layers of betulin diphosphate on aqueous solutions of zinc sulfate and on the surface of zinc oxide nanoparticles

This work examines the specific features of interaction of betulin diphosphate (BDP), exhibiting antitumor and wound-healing properties, with zinc cations during its immobilization on ZnO nanoparticles. The properties of Langmuir and transferred BDP monolayers from an aqueous subphase of zinc sulfate onto the surface of a solid substrate (CaF2, quartz) by the Langmuir—Schaefer method are investigated using IR and UV spectroscopy. It is shown that there is a twofold increase of the molecular area in the immobilized layers, while the compressibility modulus decreases by a factor of 1.5. Zinc oxide nanoparticles with immobilized BDP 10–20 nm in size (surface concentration of BDP is 100 mg g−1) retain the original hexagonal wurtzite structure. The efficiency of betulin diphosphate immobilized on the surface of zinc oxide nanoparticles is demonstrated in in vivo experiments for burn wounds in rats.

Densities and Apparent Molar Volumes of Aqueous Solutions of Zinc Sulfate at Temperatures from 293 to 373 K and 0.1 MPa Pressure

Densities of up to 16 aqueous solutions of zinc sulfate have been measured at 5 K intervals over the temperature range of 293.15 ≤ T/K ≤ 353.15 at concentrations 0.004 ≤ m/mol·kg–1 ≤ 2.5 and 0.1 MP...

Volumetric Properties of Aqueous Solutions of Zinc Sulfate at Temperatures from 298.15 to 393.15 K and Pressures up to 10 MPa

Densities of aqueous solutions of zinc sulfate at molalities ranging from 0.1 to 3.0 mol·kg–1 were measured with a commercial vibrating tube densimeter at temperatures from 298.15 to 393.15 K and a...

A Volumetric Pitzer Model for Aqueous Solutions of Zinc Sulfate up to Near-Saturation Concentrations at Temperatures from 293.15 to 393.15 K and Pressures up to 10 MPa

Literature data for the volumetric properties of aqueous solutions of zinc sulfate have been compiled and compared with extensive recently available measurements. A semi-empirical Pitzer model has ...

Effect of pH on the structural and optical properties of polycrystalline ZnSe thin films produced by CBD method

In this study, zinc selenide (ZnSe) thin films were produced on glass substrate by using chemical bath deposition (CBD) method at 80[Formula: see text]C, from aqueous solutions of zinc sulphate and sodium selenosulphide, which were produced using solid selenium as the selenium source. The optical and structural properties of ZnSe thin films were investigated at room-temperature. The pH of the chemical bath, in which ZnSe thin films were immersed, were changed between pH:8–11. Optical properties of the films, including extinction coefficient, refractive index, reflectance, absorbance, transmittance, dielectric constants and optical density values were calculated using absorbance and transmittance measurements determined using a Hach Lange 500 spectrophotometer, in 300–1100 nm wavelength range. Optical bandgap values were obtained from transmittance and absorbance spectra ranged between 2.12 and 2.49 eV. According to XRD results, it was found that the films have polycrystalline structure and they exhibited different film thicknesses depending on phase and pH changes.

One-step growth of structured ZnO thin films by chemical bath deposition in aqueous ammonia solution

Structured ZnO films have been fabricated on soda-lime glass slides at a low temperature (80–85 °C) by a chemical bath deposition method in one step without seed layers. Mixed aqueous solutions of zinc sulfate, ammonia and thiourea were used at alkaline conditions. The influence of the ammonia concentration in the initial solution on the property of the deposited film was investigated systematically. The morphology, structural and optical properties of the deposited films were examined and characterized by x-ray diffraction (XRD), energy-dispersive spectroscopy x-ray diffraction (EDX), scanning electron microscopy (SEM), Raman spectroscopy and photoluminescence (PL) spectroscopy. Structural analyses with XRD, EDX and SEM revealed that the formed films exhibit a wurtzite hexagonal phase. The deposited film was more preferentially oriented in the (0 0 2) direction with an increase in the ammonia concentration from 0.75 to 2 mol l−1. The optical-phonon E2 mode at 437 cm−1 in the Raman spectrum, together with the XRD and EDX analyses, showed that flower-like and columnar crystalline ZnO films were formed in two ammonia concentration ranges, 0.75–1.4 mol l−1 and 1.6–2.0 mol l−1, respectively. Furthermore, PL spectra showed strong and high intensity peaks of UV emission with suppressed green emission for these deposited ZnO films. ZnS films were formed with a high ammonia concentration of 3.0 M. The formation mechanisms of ZnO, Zn(OH)2 and ZnS phases were discussed.

Preparation and characterization of ZnTe thin films by SILAR method

Nanocrystalline zinc telluride (ZnTe) thin films were prepared by using successive ionic layer adsorption and reaction (SILAR) method from aqueous solutions of zinc sulfate and sodium telluride. The films were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis and optical absorption measurement techniques. The synthesized ZnTe thin films were nanocrystalline with densely aggregated particles in nanometer scale and were free from the voids or cracks. The optical band gap energy of the film was found to be thickness dependent. The elemental chemical compositional stoichiometric analysis revealed good Zn:Te elemental ratio of 53:47.

Zinc deposited polymer coatings for copper protection

Polypyrrole (PPy) and polyaniline (PAni) coatings were electrosynthesized on copper, by using cyclic voltammetry technique. Then, these coatings were modified with the deposition of zinc particles from aqueous zinc sulphate solution. The electrodeposition of zinc was achieved at a constant potential value of −1.20 V, in the amount of ∼0.75 mg/cm 2. The corrosion performance of zinc modified polymer coatings were investigated in 3.5% NaCl solution; by using the electrochemical impedance spectroscopy (EIS), and anodic polarization curves. The zinc particles improved the barrier property of polymer films, thanks to formation of voluminous zinc corrosion products within the pores of polymer coating. Also, the zinc particles provided cathodic protection to the substrate, where the polymer film played the role of conductance between zinc particles and copper.

Partial liquid phase hydrogenation of benzene to cyclohexene over ruthenium catalysts in the presence of an aqueous salt solution: I. Preparation, characterization of the catalyst and study of a number of process variables

A study has been made of the batch-wise partial hydrogenation of benzene to cyclohexene over ruthenium catalysts in the presence of an aqueous zinc sulphate solution. The reaction was performed at 423 K and at a pressure of 5.0 MPa in a stirred autoclave. The influence of a number of process variables on the performance of the catalyst, like the presence of water, the presence of salt-additives, the stirring speed, the temperature, the hydrogen pressure, the amount of catalyst, the catalyst particle size and the benzene/water ratio have been studied. It was found that it is extremely important that the catalyst is hydrophilic and therefore surrounded by a stagnant water layer; the presence of a stagnant water layer results in the suppression of the reaction rate and in a strong increase of the cyclohexene selectivity and yield. The high yield of the intermediate product, cyclohexene, which is of the order of 40 to 50 mol-%, is attributed to a physical effect, in casu severe mass transport limitation. Mass transfer calculations strongly support this conclusion.

Treatment of ovine virulent footrot with zinc sulphate/sodium lauryl sulphate footbathing.

Trials were conducted on 2 commercial sheep flocks in the Gippsland region of Victoria to determine the efficacy of treating ovine virulent footrot by footbathing in aqueous zinc sulphate solution (20% w/v). The effects of foot paring, parenteral penicillin, vaccination and addition of sodium lauryl sulphate (SLS) to the footbaths were assessed. Trial 1 comprised 297 sheep with an initial prevalence of footrot of 33% and most lesions were severe and chronic. Treatment of sheep with unpared feet by zinc sulphate footbathing for 1h did not result in a significant reduction in footrot prevalence (n = 120, cure rate 33%) whereas a significant (P less than 0.01) response was obtained by footbathing for 1h with zinc sulphate/SLS (n = 120, cure rate 55%). Trial 2 comprised 1,042 sheep with a pretreatment footrot prevalence of 71% and predominantly severe lesions. In this flock all treated sheep were footbathed in zinc sulphate/SLS for 1h on 2 occasions, 5 days apart and the effects of additional surgical and parenteral treatments were assessed. Foot paring had a significant detrimental effect on cure rate (P less than 0.01). The administration of procaine penicillin at the time of the first footbathing with zinc sulphate/SLS made no significant improvement to the rate of cure. Footrot vaccine given 8 and 2 weeks prior to footbathing did not cure significantly more sheep than footbathing alone, but the results were significantly better than from foot paring plus footbathing, and from combined foot paring, footbathing and parenteral penincillin treatment (P less than 0.01). The cure rate was 84% for sheep that were only footbathed, 72% for those foot pared and footbathed, 72% for those foot pared, footbathed and given penicillin, and 88% for those vaccinated and footbathed.

The protective effect of zinc sulphate in experimental sporidesmin poisoning of sheep

Summary Aqueous solutions of zinc sulphate were administered orally to sheep over 5 days (0.125, 0.5 and 2.0 g Zn++/sheep/day) to bracket a 3-day period during which sporidesmin also was dosed. The zinc sulphate treatment gave protection from the effects of sporidesmin when compared with control groups dosed sporidesmin alone. Body weight changes were improved and liverdamage scores, numbers of animals showing photosensitisation, serum levels of glutamic oxaloacetic acid transaminase and total bilirubin were lower. The protective effects of zinc sulphate were obtained at levels well abovethose required for growth and maintenance. Protection increased but at a diminishing rate with increasing dose rate of zinc. Because of the small safety margin which exists between the dose rate of zinc sulphate which will provide adequate protection and that which will cause toxicity the use of zinc for the control of facial eczema is not recommended.

Convection in horizontal layers with internal heat generation. Experiments

A largely qualitative experimental investigation has been made of cellular convection patterns produced by the instability of a horizontal layer of fluid heated uniformly throughout its body and cooled from above. The fluid was aqueous zinc sulphate solution, and the heating was produced by an electrolytic current. The flow was visualized and photographed using polystyrene beads which, because of a differential expansion, came out of suspension in regions where the fluid was hotter or colder than average.The development of the cellular patterns as the Rayleigh number (a modified form) was varied was in many respects similar to that for Bénard convection. There were, however, two striking differences. First, the fluid descended in the centres of the cells and ascended at the peripheries; this was probably associated with the asymmetry between the heating and cooling. Secondly, and more surprisingly, the horizontal scale of the convection patterns was unusually large (except at the lowest Rayleigh numbers); the distance between rising and falling currents was observed to reach typically five times the depth of the layer.This last observation may be relevant to theories of convection within the Earth's mantle, to mesoscale convection in the atmosphere, and to patterns formed in ice.

Ultrasonic Studies in Aqueous Solutions of Zinc Acetate

Aqueous solutions of zinc acetate of different concentrations have been studied in respect of their ultrasonic and other physical properties at various temperatures. It is noticed that in case of zinc acetate the ultrasonic absorption coefficient which was earlier found to be increasing with increase in temperature at a frequency of 20 Mc/s, is found to have a peak in the absorption Vs temperature curve at a lower frequency of 8 Mc/s. With decreasing concentrations the peak loses sharpness and ultimately at very low concentrations there is a reversal in the temperature coefficient of absorption which now decreases with the rise in temperature. The results have been discussed along with observations in aqueous solutions of zinc sulphate and acetic acid.

Electrical conductance of concentrated aqueous solutions of zinc sulphate.

Electrical conductance of concentrated aqueous solutions of zinc sulphate.

Transference Numbers in Aqueous Solutions of Zinc Sulfate

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTransference Numbers in Aqueous Solutions of Zinc SulfateE. P. Purser and R. H. StokesCite this: J. Am. Chem. Soc. 1951, 73, 12, 5650–5652Publication Date (Print):December 1, 1951Publication History Published online1 May 2002Published inissue 1 December 1951https://doi.org/10.1021/ja01156a045RIGHTS & PERMISSIONSArticle Views127Altmetric-Citations9LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (391 KB) Get e-Alerts Get e-Alerts

The nature of spongy zinc deposits, obtained by the electrolysis of aqueous solutions of zinc sulphate

The nature of spongy zinc deposits, obtained by the electrolysis of aqueous solutions of zinc sulphate