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Manganese oxide thin films were developed on soda-lime glass substrates at different deposition time, 4,6, 8, 12 and 24h, by Chemical Bath Deposition (CBD) technique, using aqueous manganese sulfate solution and ammonia, at a low temperature of 333 K. The structural, morphological and optical properties of the nano-structures of the as-prepared films were investigated by means of X-ray diffraction (XRD), Field Effect Scanning Electron Microscopy (FESEM) and Ultraviolet-Visible (UV-Vis) spectroscopy. X-ray diffraction and Raman analysis revealed that the as-prepared samples consisted of polycrystalline crystallites of tetragonal Hausmannite. FESEM image studies exposed the uniform film coverage on the substrate surfaces. Optical studies showed that the films exhibited a maximum transparency, 60% to 70%, at about 600 nm in the Vis-IR spectrum. Optical band gap varies slightly as deposition time increases from 4 to 24 h. In order to study the electrochemical behavior, we have also synthesized Manganese Oxide films on silver substrates at 333 K by Chemical Bath Deposition. The electrochemical characteristics of the film were examined by Cyclic Voltammetry (CV). The CV curves showed the capacitive behavior of the film. [ABSTRACT FROM AUTHOR]

The results of studies of the scientifically substantiated use of microelements in sweet pepper crops as an important factor in increasing the yield of vegetable crops and improving product quality are presented. The purpose of our research was to substantiate the impact of the use of microelements in the technology of cultivation of sweet pepper on the growth and development of plants, the productivity and quality of this crop. The experimental part of the work was carried out in 2014-2019 in the subzone of light chestnut soils of the Volgograd region. Experiments on the study of microelements were carried out by pre-sowing seed treatment and foliar feeding of plants. Chemically pure compounds of manganese sulphate, zinc sulphate, copper sulphate, ammonium molybdate, and boric acid were used as trace elements. The use of microelements in the conditions of the dry steppe zone of the Lower Volga region is an important agricultural technique that accelerates the growth, development, increase in yield and improves the quality of pepper fruits. It is recommended to carry out pre-sowing treatment of seeds with solutions of boric acid (0.29 g a.i. / 1 l of water), copper sulfate (0.20 g a.i. / 1 l of water) and manganese sulfate (0.16 g a.i../1 liter of water) (the ratio of seed weight to solution is 1:2), as a way to increase the viability of seeds, accelerate the yield and improve the quality of seedlings. In order to increase the yield and improve the quality during the budding period of peppers, it is necessary to carry out foliar top dressing, first of all, with solutions of boric acid (0.29 g a.i. / 1 l of water), ammonium molybdate (0.10 g a.i. / 1 l water), water consumption 1 l/10 m2. Due to high efficiency, simplicity and availability, pre-sowing seed treatment and foliar feeding of plants with microelements will be widely used in vegetable growing. [ABSTRACT FROM AUTHOR]

It is a great challenge to produce a battery with electrochemical properties. Efforts have been conducted by researchers to produce batteries with good capacity and long-life cycle. In this work, a series of batteries consisted of LiFe0.5Mn0.5PO4/V/C composite cathode have been successfully synthesized via hydrothermal method with and without ultrasonic pretreatment. Lithium hydroxide, ammonium phosphate, manganese sulfate monohydrate, and iron phosphate heptahydrate were used as starting materials. Citric acid was added as both carbon source and reducing agent, and vanadium salts was added as dopant to improve the retention time for longer life cycle. Characterization was performed by scanning electron microscope equipped with energy dispersive X-ray spectroscopy for morphology and elemental composition, X-ray diffraction for crystal structure, and cyclic voltammetry for electrochemical properties. The results showed agglomerated structure for sample without ultrasonic pretreatment and fine octahedral structure for sample with ultrasonic pretreatment, a distinctive x-ray diffraction pattern and high voltage up to 4.4 V for the potential difference. More works are yet to be further done for the improvement of the capacity. [ABSTRACT FROM AUTHOR]

NMC is a lithium-ion battery that combines three primary metals, namely Nickel, Manganese, and Cobalt. Manganese metal is used in the form of manganese sulfate (MnSO4). This research has studied the effect of adding alkali in the precipitation of impurities from the solution of manganese ore leaching on the crystals of MnSO4 as raw material for the manufacture of NMC. Some manganese ores are leached using oxalic acid as a reducing agent in a sulfuric acid atmosphere. Then, the impurities (mainly iron) precipitation from pregnant leached solution was carried out with pH adjustment using various alkalis. The alkalis used in this study were NaOH, NH4OH, and Ca(OH)2. The MnSO4 products were characterized using XRF and XRD. The results showed that the use of Ca(OH)2 in the precipitation of iron and other impurities from the pregnant leached solution could provide better MnSO4 crystals than the use of NaOH and NH4OH. [ABSTRACT FROM AUTHOR]

The Li-NMC cathode battery production usually applies carbonate precipitation processes. Manganese compound used is in the form of manganese sulfate (MnSO4) and precipitate using carbonate to produce manganese carbonate. This research has studied the synthesis of manganese carbonate from Indonesian manganese ore as raw material for the manufacture of NMC cathode precursor. Some manganese ores are leached using oxalic acid as a reducing agent in a sulfuric acid atmosphere. This leaching process was conducted using sulfuric acid with a concentration of 6%, leaching temperature 80oC, for 6 hours, oxalic acid used 30 g/liter, with a ratio of ore to the sulfuric acid solution was 52.63 gr/l. Then, the impurities (mainly iron) precipitation from pregnant leached solution was carried out with pH adjustment using various alkalis. The alkalis used in this study were NaOH, Na2CO3, and NH4OH. Manganese carbonate products were characterized using XRF and XRD. The results showed that manganese carbonate with high purity (>95%) can be synthesized from Indonesian manganese ore using leaching and precipitation method. [ABSTRACT FROM AUTHOR]

The paper is directed at studying foliar dressing of grain crops with microelements, which, in turn, is an effective way to increase productivity. The paper presents the equation and the corresponding three-dimensional surface graph, obtained with the use of correlation and regression analyses, which make it possible to calculate the yield of bread flour of the 1st grade depending on the method of using manganese sulfate and zinc sulfate in the technology of winter wheat cultivation. [ABSTRACT FROM AUTHOR]

The prenatal effect of manganese sulfate on the behavioral parameters of the body and the concentration of acetylcholinesterase in the blood serum was studied. For this purpose, female Wistar rats received manganese sulfate at a daily dose of 2/3LD50 in addition to the main diet for 28 days before and during pregnancy (20-26 days). Young offspring were tested for the detection of behavioral disorders using standardized behavioral tests. According to the results of the tests, males with the greatest deviations were selected. The animals of this group were hyperactive. On reaching 18 weeks of age, blood was collected from the selected male rats to determine the level of acetylcholinesterase. The effect of oral exposure to manganese on the body of female mothers was also evaluated. The study showed that the serum of female rats exposed to direct exposure to manganese sulfate tended to have higher levels of acetylcholinesterase. Statistically significant changes in the level of this enzyme were observed in animals of the first generation: the Q25 value of the first experimental group was more than the Q75 of the group that was not exposed to prenatal exposure by 22% (p = 0.012). The study therefore demonstrated that prenatal exposure to manganese sulfate can affect the behavior and concentration of acetylcholinesterase in offspring. [ABSTRACT FROM AUTHOR]

Lithium-ion battery (LIB) as one of the important energy storage devices and attracts attention due to its high specific capacity and long cycling life. Among several cathode materials studied, spinel LiMn2O4 is promising due to its great advantages such as abundant precursor, low cost, environmental friendliness, high working voltage and intrinsic thermal stability under severe environmental conditions. In this study, LiMn2O4 was prepared from manganese-based fertilizer with the addition of oxalic acid, sodium hydroxide, and soda ash as precipitant. All of the samples were characterized using XRD, FTIR and SEM. The LiMn2O4 structure was successfully formed based on the XRD test results. SEM results LiMn2O4 showed that the material has micron sized polyhedral shape, specifically octahedral shape. EDX study shows there is no impurities. Charge and discharge analysis of as obtained LiMn2O4 using artificial graphite as the anode shows a charge capacity of 116 mAh/g and a discharge capacity of 115 mAh/g which is an outstanding result since an economical and abundant fertilizer was used as the main raw materials. [ABSTRACT FROM AUTHOR]

The paper deals with the modifying effect of iron sulfate and manganese sulfate which are introduced to aluminum hydroxide on the textural characteristics and phase composition of the alumina matrix used as a carrier for sulfated zirconia catalysts for hexane isomerization. The addition of iron sulfate and manganese sulfate improves the catalytic performance of the supported sulfated zirconia catalysts which is characterized by an increase in the isomerization depth to 27–31 %. The yield of the sum of isomers on the catalyst with the addition of FeSO4 reaches 81 % wt., and with the addition of MnSO4 – 84 % wt. [ABSTRACT FROM AUTHOR]

Molecular influence between the solute and solvent of aqueous polyvinyl pyrrolidone (PVP) with aqueous Zinc sulphate, Manganese sulphate, Zinc chloride and Manganese Chloride, 303, 308 and 313 K have been observed through thermo physical parameters. The physical parameters such as Molar volume, classical absorption coefficient, and cohesive energy have been calculated from the measured data of ultrasonic velocity, density and viscosity of the liquid mixtures at various concentrations at different temperatures. FTIR spectroscopic studies were made in the liquid mixtures of sulphates and chlorides with aqueous PVP. The observed data and plots of the liquid mixtures confirm the presence of strong molecular interactions between the molecules. [ABSTRACT FROM AUTHOR]

The manganese bath activation technique has been developed and actively used for neutron emission rate measurements at the laboratory of the Institute of Nuclear and Physical Engineering FEI STU since 2015. For this technique a spherical Plexiglas vessel with manganese sulfate solution and Pu-Be isotope neutron source is used, which is before and after the emission rate measurement transported using a special source loading mechanism. Since all activities involved in the work with sources of radiation must be in line with the ALARA (As Low As Reasonably Achievable) principle, it is necessary to estimate the radiation situation during the source loading procedure and to optimize the measurement process. This paper focuses on the simulation of the radiation situation in case of these transportation process, based on Monte Carlo simulation using the detailed model of the experimental workspace developed in the SCALE6 system. The model consists of geometry configurations that can influence the attenuation of gamma and neutron radiation. To estimate the radiation situation 3D neutron and gamma mesh tallies and 5 point detectors, placed at specific positions, are used. The paper includes the achieved results of the dose rates as well as discussion on the optimization of the measurement process. [ABSTRACT FROM AUTHOR]

The aims of this research were to study the leaching process of manganese ore which originated from Sumbawa, Indonesia and its characterization. A high grade Indonesian manganese ore from Sumbawa, West of Nusa Tenggara was characterized by X-Ray Fluorescence (XRF). The result showed composition of 78.8 % Mn, 17.77% Fe and the rest were trace elements such as Si, Co, Ti, Zn, V and Zr contents. X-Ray Diffraction analysis showed that the manganese ore was consisted of pyrolusite (MnO2), rhodonite (MnSiO3), rhodochrosite (MnCO3) and hematite (Fe2O3). Manganese ore was also analyzed by thermal analysis to observe their thermal decomposition character. In this study, sulphuric acid (H2SO4, 6 M) was deployed as leaching agent. The leaching process was performed at 90 °C for two hours with the addition of NH4OH to control pH. Recovery percentage of leaching process yielded of 87 % Mn extracted. The crystallization process result at heating temperature of 200 °C was confirmed by XRD as manganese sulfate. [ABSTRACT FROM AUTHOR]