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Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The field of functional nanohybrid material is an emerging research area in material science due to its vast range of applications. The use of novel technology and innovative therapeutics has led to potent applications, including controlling the size of nanoparticles (NPs). This has resulted in a novel report on the synthesis of manganese oxide NPs using aerial parts of queen of roses Prunus dulcis (almond) leaves, seed, and seed oil (using Clevenger apparatus), which functions as a reducing agent. Manganese sulfate was used as a precursor in the synthesis process. The synthesized nanohybrid Mn3O4 NPs were studied using different characteristics techniques such as X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy‐dispersive X‐ray spectroscopy (EDX). The photoluminescence spectra display the blue emission ranging from 483.2 to 486.5 nm. The biosynthesized Mn3O4 NPs were tested for bactericidal activity and showed tremendous inhibition against gram‐positive and gram‐negative bacteria. The antioxidant activity of Mn3O4 NPs was enhanced using 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) assay, which revealed the higher activity of Mn3O4 NPs from P. dulcis leaf extract. In vitro cytotoxicity of hybrid Mn3O4 NPs was examined using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay against cervical cancer (HeLa cell line) with different concentrations. The results showed an IC50 value of 61.97 μg mL−1 for Mn3O4 NPs from P. dulcis leaf extract. In general, the phytosynthetic route with synergistic effect of nanohybrid demonstrated an interaction with cancer cells, highlighting a pioneering optimum approach in synthesis of Mn3O4 NPs from aerial parts of P. dulcis. [ABSTRACT FROM AUTHOR]

Manganese oxide has been studied as a promising supercapacitor electrode due to its high theoretical capacitance, low cost, and environmental friendliness. Supercapacitor performance such as specific capacitance, resistance, and cycle life greatly depends on the morphology and crystal structure of manganese oxide. In this study, a Mn3O4 hybrid structure was successfully synthesized using electrodeposition and successive ionic layer adsorption and reaction (SILAR) techniques which are simple, cost-effective, and low-temperature wet chemical processes. It was found that Mn3O4 morphology is different depending on manganese precursors and synthesis techniques. Sea-grape-like and bird nest-like morphologies were obtained via the electrodeposition technique, while flower-like and nanoparticle morphologies were formed via the SILAR technique using manganese acetate and manganese sulfate as precursors, respectively. The hybrid structure of the nanoparticle-decorated bird nest-like heterostructure was prepared using manganese sulfate electrodeposition and subsequent SILAR deposition of manganese acetate. X-ray photoelectron spectroscopy confirmed the Mn3O4 formation. Electrochemical properties of manganese oxide hybrid structure were systematically studied with cyclic voltammetry and galvanostatic charge–discharge, showing the highest areal capacitance of 390 mF cm−2 at 0.1 mA cm−2 with series and charge transfer resistances down to 4.55 and 4.91 Ω in 1 M sodium sulfate electrolyte. [ABSTRACT FROM AUTHOR]

Copyright of Hydrometallurgy of China is the property of Hydrometallurgy of China Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to evaluate the relative bioavailability value (RBV) of different manganese mono oxide (MnO) sources and manganese sulfate (MnSO4) in broiler diets as well as their effect on tibial characteristics, and serum inorganic phosphorous (P), calcium (Ca) and Mn concentrations. The experiment was carried out based on a completely randomized design (CRD) with 660 broiler chicks (Ross 308) assigned to 12 dietary treatments with 6 replicates of 10 birds each. The experimental diets consisted of one basal diet (as control), and 10 treatment groups which were supplemented with 400 or 800 mg/kg of feed of 1-5 MnO sources with 35%, 25%, 45-55%, 30%, and 40% purities, respectively; MnSO4 was also used (800 mg/kg of feed) in a treatment group as a reference standard with 100% bioavailability. The mean RBV of MnO sources (27.27 to 181.82%) showed a significant difference (P<0.05). The results also showed sera Ca and Mn concentrations, and retention of Mn in diet and tibia bone were significantly affected by different Mn sources used (P<0.05). Although no differences were observed for sera P, Ca, and Mn concentrations, regardless of the level of supplementation (P<0.05). The results of this study demonstrated that the purity of Mn supplement sources has a relationship with RBV of Mn, Mn absorption, and its retention in broiler bone and ileum. [ABSTRACT FROM AUTHOR]

A series of MnM/palygorskite (PG) (M = La, W, Mo, Sb, Mg) catalysts was prepared by the wetness co-impregnation method for low-temperature selective catalytic reduction (SCR) of NO with NH 3. Conversion efficiency followed the order Sb > Mo > La > W > Mg. A combination of various physico-chemical techniques was used to investigate the influence of Sb-modified Mn/PG catalysts. MnSb 0.156 /PG catalyst showed highest NO conversion at low temperatures in the presence of SO 2 which reveals that addition of Sb oxides effectively enhances the SCR activity of catalysts. A SO 2 step-wise study showed that MnSb 0.156 /PG catalyst displays higher durable resistance to SO 2 than Mn/PG catalyst, where the sulfating of active phase is greatly inhibited after Sb doping. Scanning electron microscopy and X-ray diffraction results showed that Sb loading enhances the dispersion of Mn oxides on the carrier surface. According to the results of characterization analyses, it is suggested that the main reason for the deactivation of Mn/PG is the formation of manganese sulfates which cause the permanent deactivation of Mn-based catalysts. For Sb-doped Mn/PG catalyst, SO x ad-species formed were mainly combined with SbO x rather than MnO x. This preferential interaction between SbO x and SO 2 effectively shields the MnO x as active species from being sulfated by SO 2 resulting in the improvement of SO 2 tolerance on Sb-added catalyst. Multiple information support that, owing to the addition of Sb, original formed MnO x crystallite has been completely transformed into highly dispersed amorphous phase accounting for higher SCR activity. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Manganese is an element of interest in metallurgy, especially in ironmaking and steel making, but also in copper and aluminum industries. The depletion of manganese high grade sources and the environmental awareness have led to search for new manganese sources, such as wastes/by-products of other metallurgies. In this way, we propose the recovery of manganese from anodic lodes and scrapings of the zinc electrolysis process because of their high Mn content (>30%). The proposed process is based on a mixed leaching: a lixiviation-neutralization at low temperature (50 °C, reached due to the exothermic reactions involved in the process) and a lixiviation with sulfuric acid at high temperature (150-200 °C, in heated reactor). The obtained solution after the combined process is mainly composed by manganese sulphate. This solution is then neutralized with CaO (or manganese carbonate) as a first purification stage, removing H2SO4 and those impurities that are easily removable by controlling pH. Then, the purification of nobler elements than manganese is performed by their precipitation as sulphides. The purified solution is sent to electrolysis where electrolytic manganese is obtained (99.9% Mn). The versatility of the proposed process allows for obtaining electrolytic manganese, oxide of manganese (IV), oxide of manganese (II), or manganese sulphate. [ABSTRACT FROM AUTHOR]

Nanorod Mn 3 O 4 anchored on graphene nanosheet (Mn 3 O 4 @GNS) using GNSs and MnSO 4 ·H 2 O as precursor materials have been prepared by a simple, effective and scalable method. The nanorod Mn 3 O 4 @GNS as anode materials in lithium-ion batteries exhibits the better electrochemical properties in the composite than the bare nanorod Mn 3 O 4 owing to its special structure, including a maximum reversible specific capacity of 1155.2 mA h g −1 at 100 mA g −1 , and the extraordinary cycling stability, with no decay in capacity for up to 100 cycles. The nanorod Mn 3 O 4 @GNS could be a promising candidate material for high reversible specific capacity, stable columbic efficiency, long cycle life and outstanding rate capacity. This study would offer a new method to improve the properties of insulating materials, holding a promising potential for high-performance lithium-ion batteries in energy storage fields. [ABSTRACT FROM AUTHOR]

Beta-manganese dioxide (β-MnO) microrods were hydrothermally synthesized from ammonium persulfate [(NH)SO] solution using manganese sulfate (MnSO) as reductant at 180 °C for 3 h. The characterizations, including X-ray diffraction, scanning electron microscopy, and transmission electron microscopy, showed that the crystallinity and morphology of the as-synthesized samples were well-defined β-MnO microrods with the diameters of about 100 nm and lengths of about 2-4 μm. To explore the optimal degradation conditions, the as-synthesized β-MnO microrods were employed into the degradation of methyl orange dye solution with the concentration of 20 mg/L in the presence of H with pH values equalling 1.0, 1.5, 2.0, 3.0, 5.0, and 7.0, respectively. The results indicate that the degradation efficiency could reach 98% after 9 min at the pH value of 1.0 or 2.0. Also, the lower the pH value, the higher the degradation efficiency. Based on these experimental results, a proper mechanism of the degradation process of methyl orange is proposed and the rationality of the mechanism is further investigated through the scientific control tests. [ABSTRACT FROM AUTHOR]

We prepared MnO by electrolysis of manganese sulfate solution recovered from used batteries and commercial manganese sulfate solution. The comparative study of the two samples using electrochemical techniques in alkaline solution shows that the two samples exhibit the same behavior. From XRD, we identified and indexed both samples by γMnO orthorhombic structure. We estimated the proton diffusion coefficient using galvanostatic intermittent titration technique (GITT). Our calculated data are in good agreement with theoretical values for both samples. In addition TG analysis shows the same thermal profile for both samples. [ABSTRACT FROM AUTHOR]

A series of Mn-based activated carbon catalysts were prepared by excessive impregnation with or without ultrasonic assistance, and manganese (Mn) species and surface chemical properties of catalysts before and after SO2 removal were studied. The results showed that different preparation conditions significantly influence the desulfurization activity of Mn-based activated carbon catalysts. The breakthrough sulfur capacity of 5FMn/ACA36 prepared by ultrasonic assisted excessive impregnation is 73.0 mg g−1, while that of 5FMn/ACN36 increases to 126.1 mg g−1. The catalysts exhibit different desulfurization activities when carbon carriers are pretreated with nitric acid at different concentrations, and with the increase of concentrations, the breakthrough sulfur capacity of catalysts increases from 118.1 to 141.6 mg g−1. Catalysts calcined at different temperatures show different desulfurization activities. Both 5FMn/ACW and 5Mn/ACW calcined at 800 °C have the best desulfurization activity, but 5FMn/ACN36 and 5Mn/ACN36 calcined at 650 and 800 °C are similar. The optimal loading of catalysts prepared by excessive impregnation is 7%, but that of catalysts prepared by ultrasonic assisted excessive impregnation is 0.5%. Nitric acid pretreatment can change surface chemical properties and reduce the formation temperature as well as the crystalline size of Mn oxide species such as MnO and Mn3O4. The introduction of ultrasonic oscillation cannot change active species and oxygen-containing functional groups (such as C–O, C=O and O=C–OH) but reduce the active component content to enhance the activity. Mn loading influences the content of active components and oxygen-containing functional groups on carbon supports, leading to a different desulfurization activity. After SO2 removal, MnO, Mn2O3 and Mn3O4 are still observed, but some of them transform into MnO2 with low crystallinity, and some react with generated H2SO4 to form MnSO4, resulting in catalyst deactivation. Types of oxygen-containing functional groups after SO2 removal remain the same but the relative contents decrease, showing that they participate in the reaction of SO2 removal. [ABSTRACT FROM AUTHOR]

A process to prepare Mn3O4 in the mixed solvent of water and ethanol under hydrothermal condition was studied, in which manganese sulphate was used as raw material, manganese hydroxide from precipitation with sodium hydroxide as a precursor, potassium permanganate as oxidant. The influences of the factors on Mn mass percentage (Mn wt-%) in manganese oxide product, including potassium permanganate dosage, solvent composition, temperature and time of the hydrothermal reaction as well as drying temperature, were analysed. Potassium permanganate dosage could be a third of the theoretical amount because of the auxiliary oxidation of existent O2 in the process. The results show that the optimal conditions are hydrothermal temperature 433 K and time 2-4 hours, solvent composition (ethanol/(ethanol + water), in volume) 0·33 and drying temperature 393 K, Mn wt-% in the optimal product exceeds 71% and Na content meets the standard of magnetic material. [ABSTRACT FROM AUTHOR]

Herein we report a one-step approach to the highly efficient synthesis of graphene oxide/Mn 3 O 4 (GO/Mn 3 O 4 ) hybrids with superior catalytic activities for decomposition of methylene blue (MB) in water. This method exploits the pristine graphene oxide/manganese sulfate (GO/MnSO 4 ) suspension produced by the modified Hummers method as the raw materials, in which GO/MnSO 4 has been in situ converted into GO/Mn 3 O 4 hybrid in combination with KOH and air. This atom-economic reaction produces only K 2 SO 4 crystal as the by-product which meets the standard of green chemistry. For catalystic degradation of MB dye at room temperature, the as-prepared GO/Mn 3 O 4 catalysts result in a significant enhancement in the reaction rate compared to that of the bare Mn 3 O 4 particles with the assistance of H 2 O 2 . Typically, 50 mL of MB (50 mg L −1 ) can be 100% decolorized and 77% mineralized with 10 mg of the GO/Mn 3 O 4 hybrid. Such excellent catalytic performance of the GO/Mn 3 O 4 hybrid is mainly attributed to the synergistic effects of GO, Mn 3 O 4 , H 2 O 2 and MB molecules. Based on the hydroxyl radical experiments, the catalytic activity of GO/Mn 3 O 4 hybrids for degradation of MB is closely related with the amount of the reactive •OH species generated from H 2 O 2 . [ABSTRACT FROM AUTHOR]

Micro-spherical manganic manganous oxide was prepared by a controlled crystallization process. The synthesized product was characterized by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The element was analyzed by inductive coupled plasma (ICP). The effects of different operation conditions including the type of oxidant, amount of ammonium (ammonium-to-manganese ratio), manganous sulfate concentration, temperature and time of reaction on the purity, surface area and morphology were investigated. The results show that the purity and surface area of the obtained micro-spherical manganic manganous oxide at optional conditions are 99.63% and about 0.91±0.02m2·g−1, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Due to their physicochemical characteristics, metal oxide nanoparticles (NPs) interact differently with cells compared to larger particles or soluble metals. Oxidative stress and cellular metal uptake were quantified in rat type II alveolar epithelial cells in culture exposed to three different NPs: manganese(II,III) oxide nanoparticles (Mn3O4-NPs), the soluble manganese sulfate (Mn-salt) at corresponding equivalent doses, titanium dioxide (TiO2-NPs) and cerium dioxide nanoparticles (CeO2-NPs). In the presence of reactive oxygen species an increased apoptosis rate was hypothesized. Oxidative stress was assessed by detection of fluorescently labeled reactive oxygen species and by measuring intracellular oxidized glutathione. Catalytic activity was determined by measuring catalyst-dependent oxidation of thiols (DTT-assay) in a cell free environment. Inductively coupled plasma mass spectrometry was used to quantify cellular metal uptake. Apoptosis rate was determined assessing the activity of caspase-3 and by fluorescence microscopic quantification of apoptotic nuclei. Reactive oxygen species were mainly generated in cells treated with Mn3O4-NPs. Only Mn3O4-NPs oxidized intracellular glutathione. Catalytic activity could be exclusively shown for Mn3O4-NPs. Cellular metal uptake was similar for all particles, whereas Mn-salt could hardly be detected within the cell. Apoptosis was induced by both, Mn3O4-NPs and Mn-salt. The combination of catalytic activity and capability of passing the cell membrane contributes to the toxicity of Mn3O4-NPs. Apoptosis of samples treated with Mn-salt is triggered by different, potentially extracellular mechanisms. [Copyright &y& Elsevier]

Abstract: The main objective of this work is to develop a hybrid water-splitting cycle that employs the photon component of sunlight for production of H2 and its thermal (i.e. IR) component for generating oxygen. In this paper, (NH4)2SO4 thermal decomposition in the presence of Mn3O4, as an oxygen evolving step, was systematically investigated using thermogravimetric/differential thermal analyses (TG/DTA), temperature programmed desorption (TPD) coupled with a mass spectrometer (MS), X-ray Diffraction (XRD), and X-ray Photoelectron Spectroscopy (XPS) techniques. Furthermore, thermolysis of ammonium sulfate, (NH4)2SO4, in the presence of Mn3O4 was also investigated by conducting flow reactor experiments. The experimental results obtained indicate that at 200–450 °C, (NH4)2SO4 decomposes forming NH3 and H2O and sulfur trioxide that in the presence of manganese oxide react to form manganese sulfate, MnSO4. At still higher temperatures (800∼900 °C), MnSO4 further decomposed forming SO2 and O2. [Copyright &y& Elsevier]

Nanoscale manganese oxide with different morphologies were developed at room temperature using different precursor salts (potassium permanganate and manganese sulfate). The obtained nanoscale morphologies, i.e., rod and sphere-shaped were characterized using BET surface area analyzer, SEM, TEM, and XRD. The manganese oxide possessed the rod and sphere-like morphologies with different pore structures. The adsorption of methylene blue on mesoporous manganese oxide followed the pseudo-second-order kinetics and best fitted with the Freundlich adsorption isotherm model with a removal capacity of 2914 mg g−1. The effect of irradiation time on degradation efficiency was also examined, which followed the first-order kinetics with a degradation efficiency of 93.12%. Furthermore, the recycling studies revealed that the spherical manganese oxide retained over 90% of the photodegradation efficiency after three cycles of methylene blue degradation, which proves its stability for practical applications. Therefore, mesoporous manganese oxide with significant adsorption and remarkable photodegradation capability can provide a way forward to fine-tune the material's properties for effective environmental remediation. [Display omitted] • Development of nanoscale manganese oxide rods and sphere using simple precipitation route. • Manganese oxide properties (morphology and pore structure) can be tuned by precursor salt. • The manganese oxide possesses an adsorption capacity of 2914 mg g−1 at a high concentration of dye. • The manganese oxide can degrade 92.12% of methylene blue at low concentrations. [ABSTRACT FROM AUTHOR]