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manganeseoxides, etc ; lepidocrocite; oxidation; pollutants; sorption; toxicity; China; Show all 7 Subjects
Abstract:
... Antimony (Sb) is a recognized priority pollutant with toxicity that is influenced by its migration and transformation processes. Oxidation of Fe(II) to Fe(III) oxides, which is a common phenomenon in the environment, is often accompanied by the formation of Mn(III/IV) and might affect the fate of Sb. In this study, incorporated Mn(III) and sorbed/precipitated Mn(III/IV) associated with lepidocroci ...
manganeseoxides, etc ; Bacillus (bacteria); arsenates; arsenic; arsenites; bacteria; groundwater; synergism; Show all 8 Subjects
Abstract:
... Iron-manganese binary oxides (Fe-Mn oxides) have the potential to immobilize arsenite/arsenate [As(III/V)] in situ in natural environments. However, the As(III/V) immobilization performances of Fe-Mn oxides in the presence of indigenous metal-reducing bacteria in reducing groundwater systems have received limited attention. Here, As(III/V) immobilization by Fe-Mn oxides and the interactions of Fe ...
manganeseoxides, etc ; Alicyclobacillus; bacterial communities; community structure; iron; irradiation; soil pH; soil remediation; Show all 8 Subjects
Abstract:
... Nano zero-valent iron (nZVI) is used for soil remediation; however, the impact of nZVI on soil solid iron phases and its interactions with soil microorganisms in relation to the fate of Cd in soil remains unclear. In the current study, we investigated the mechanisms underlying the change in mobility of Cd in exogenous Cd-contaminated soil with nZVI and γ radiation treatments. The results showed th ...
Margarita Gutierrez-Ruiz; Alejandra Muro-Puente; Agueda E. Ceniceros-Gómez; Daniel Amaro-Ramírez; Leticia Pérez-Manzanera; L Gerardo Martínez-Jardines; Francisco Romero
manganeseoxides, etc ; electrical conductivity; environmental management; geochemistry; mineralization; pH; people; pollutants; rivers; sediments; toxicity; watersheds; Show all 12 Subjects
Abstract:
... The Sonora River and its tributary streams (Tinajas, Bacanuchi) were impacted in 2014 by an acid solution spill (approximately 40,000 m³). This study aims to presents a clear and supported overview to determining the spill's consequences on the environment and the people inhabiting the area. The elements quantified were those found in the spilled solution: Al, As, Cu, Fe, Mn, Pb, and Zn. Potential ...
... The present study evaluates the sustainability of tobacco-rice rotation by reducing the phytoavailability of cadmium (Cd) to rice by combining large-scale field sampling and regional investigations in southern China. The rotation involves frequent tillage and liberal application of nitrogen and phosphorus fertilizers, which increases yields but lowers soil pH. As a result, manganese is lost from s ...
manganeseoxides, etc ; adsorption; arsenic; oxidation; China; Show all 5 Subjects
Abstract:
... Hausmannite is a common low valence Mn oxide mineral, with a distorted spinel structure, in surficial sediments. Although natural Mn oxides often contain various impurities of transitional metals (TMs), few studies have addressed the effect and related mechanism of TM doping on the reactivity of hausmannite with metal pollutants. Here, the reactivity of cobalt (Co) doped hausmannite with aqueous A ...
manganeseoxides, etc ; adsorbents; adsorption; groundwater; oxidation; research; Show all 6 Subjects
Abstract:
... Fe-Mn binary oxide has received increasing interest in treating As(III)-containing polluted groundwater due to its low cost and environmental friendliness. Although the stability of Fe-Mn binary oxide is as important as its adsorption ability, little is known about whether and why Fe-Mn binary oxide is stable during As(III) removal. In this study, five successive cycles were conducted to evaluate ...
manganeseoxides, etc ; carbonates; fractionation; land; multivariate analysis; organic matter; pH; saline soils; salinity; sodicity; soil salinity; water solubility; zinc; Pakistan; Show all 14 Subjects
Abstract:
... The present study aimed to assess the relationship of soil properties in salt-affected soils. The soil samples were collected from 14 districts of Pakistan. Soil salinity and sodicity are the common features of the arid and semiarid regions. The effects of the salt’s interactions with soil micronutrients have not been well studied. Therefore, saline and non-saline soil samples were collected from ...
manganeseoxides, etc ; ammonium; ammonium nitrogen; autumn; biogeochemistry; dissolved oxygen; eutrophication; heavy metals; iron; karsts; nitrate reduction; nitrogen; particulates; phosphorus; pollution; research; risk; summer; temperature; Show all 19 Subjects
Abstract:
... The eutrophication of reservoirs can change the physicochemical parameters of water, thus affecting the migration and transformation of heavy metals. At present, there is insufficient research on the coupling mechanisms between nutrients and heavy metals, especially between heavy metals in suspended particles. In this paper, spatial and temporal distribution characteristics of nutrients dissolved ...
manganeseoxides, etc ; anodes; electrical conductivity; electrochemistry; energy; graphene; manganese; nanocomposites; temperature; Show all 9 Subjects
Abstract:
... We report a facile method to prepare graphene coated core-shell Mn₃O₄ nanoparticles encapsulated in hollow carbon sphere (HCS) (G–HCS–Mn₃O₄). HCSs were firstly prepared at high temperature based on a core-shell template, leading to good electrical conductivity of 21.6 S m⁻¹. The porous shells of HCSs provide passage for the manganese precursors and big cavities to store the inorganic particles. Fu ...
manganeseoxides, etc ; cathodes; electrochemistry; energy density; lithium; nanotubes; pyrroles; reaction kinetics; sulfur; Show all 9 Subjects
Abstract:
... Lithium-sulfur batteries have attracted numerous attentions owing to their high theory discharge specific capacity and energy density. However, sulfur cathode usually suffers from poor cycle stability and slow reaction kinetics, caused by its poor conductivity, excessive volume changes during charge/discharge processes, complex sulfur species conversion reaction and the dissolution of polysulfide ...
manganeseoxides, etc ; adsorption; ammonium; arsenites; birnessite; groundwater; oxidation; oxygen; pH; pollution; surface area; Show all 11 Subjects
Abstract:
... Triclinic birnessite (TB), a typical layered Mn oxide which is abundant naturally occurring minerals with a vital impact on the transformation of arsenite (As(III)) by adsorption and oxidation. As one of the most common critical metalloids, ammonium ion (NH₄⁺) universally coexists with birnessite in marine, sediments or groundwater where are contaminated with As(III). In this study, we investigate ...
manganeseoxides, etc ; absorption; adsorbents; adsorption; aqueous solutions; arsenic; catalytic activity; colorimetry; detection limit; Show all 9 Subjects
Abstract:
... Several researches have reported that Mn₃O₄ nanoparticles (NPs) could be used as adsorbent to remove arsenic from aqueous solution. However, we found that Mn₃O₄ NPs can not only adsorb arsenic, but also enhance the catalytic activity of Mn₃O₄ NPS, which enable us to establish a new method for the determination of arsenic. Herein, the adsorption of arsenic changes surface morphology of octahedral M ...
manganeseoxides, etc ; bentonite; concentrates; kaolinite; materials; montmorillonite; pH; powders; pressure; recycling; technology; water; Show all 12 Subjects
Abstract:
... Cold, binder-free tableting experiments under controlled pressure (0-450 MPa), water addition (0-10 wt.%) and pH (4, 11) were performed on powder of pyrolusite ore concentrates, refined hausmannite, bentonite, kaolinite, as well as blends of those materials. It has been shown that increased pressure was beneficial for agglomeration of oxide materials, but pressure > 250 MPa triggered an elastic re ...
manganeseoxides, etc ; Ascomycota; adsorption; chromium; environmental science; fungi; manganese; metabolites; oxidants; oxidation; technology; Show all 11 Subjects
Abstract:
... Manganese (Mn) oxides are considered as the primary oxidant of trivalent chromium [Cr(III)] in the environment. Microbial activities are responsible for the majority of Mn oxide formation in nature, thus likely influencing Cr(III) oxidation. Previous studies have been limited to Cr(III) oxidation by bacterial Mn oxides. Herein, we report coupled Mn(II) and Cr(III) oxidation in the presence of thre ...
manganeseoxides, etc ; alcohols; electron transfer; half life; hydroxyl radicals; oxidation; quantitative analysis; technology; Show all 8 Subjects
Abstract:
... The hydroxyl radical, •OH, is one of the most reactive free radicals and plays significant roles in the oxidative degradation of organic pollutants and the electron transfer of inorganic ions in natural and engineered environmental processes. To quantitatively determine the contribution of •OH to oxidative reactions, a specific scavenger, such as tert-butyl alcohol (TBA), is usually added to elimi ...
manganeseoxides, etc ; environmental management; food availability; paddies; redox potential; rice; water management; wetlands; Show all 8 Subjects
Abstract:
... Rice is a crucial part of the world's food supply but is also susceptible to uptake of contaminants including arsenic (As) and cadmium (Cd) depending on the soil redox potential. Careful control of soil redox state by implementing alternate wetting and drying (AWD) water management can decrease mobility of soil As and Cd, but can be difficult to manage. Indicators of reduction in soil (IRIS) tubes ...
manganeseoxides, etc ; electric potential difference; energy density; enthalpy; hysteresis; oxygen; reaction mechanisms; sodium; Show all 8 Subjects
Abstract:
... Oxygen redox (OR) reactions in sodium layered oxide cathodes have been studied intensively to harness their full potential in achieving high energy density for sodium-ion batteries (SIBs). However, OR triggers a large hysteretic voltage during discharge after the first charge process for OR-based oxides, and its intrinsic origin is unclear. Therefore, in this study, an in-depth reinvestigation on ...
manganeseoxides, etc ; air; catalysts; catalytic activity; energy; isopropyl alcohol; oxidation; oxygen; surface area; temperature; Show all 10 Subjects
Abstract:
... Thermal catalytic oxidation is an important method for organic gaseous compounds degradation, which has been researched intensively. Here, Cr-doped Mn₃O₄ thermal catalyst with high-performance was synthesized by using a facile calcination method. Cr-doped Mn₃O₄ exhibited a large specific surface area, narrow band gap, and abundant oxygen vacancies. Cr-doped Mn₃O₄ presented an enhanced thermal cata ...
manganeseoxides, etc ; adsorption; capacitance; carbon nanotubes; electrical resistance; electrochemical capacitors; electrochemistry; isopropyl alcohol; microstructure; nanocomposites; Show all 10 Subjects
Abstract:
... In this study, results from a conceptually new method for the preparation of Mn₃O₄-multiwalled carbon nanotube (MCNT) composites are presented. High active mass (HAM) Mn₃O₄-MCNT cathodes are prepared and tested for supercapacitors. The method is based on a salting-out aided dispersive extraction of Mn₃O₄ particles precipitated in an aqueous phase to isopropanol and their co-dispersion with MCNT. T ...