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Emerging contaminants are considered as some substances of actual or potential threat to human health or environment, which include pharmaceutical, personal care products, endocrine disruptors, nanoparticles, antibiotic resistance genes and chemicals used in packaging products, etc. How to treat these emerging pollutants in water bodies with green, high efficiency and low-cost has become the focus of attention. The purpose of this review is to summarize published researches on emerging pollutants treatment in 2017. [ABSTRACT FROM AUTHOR]

Emerging contaminants are considered as some substances of actual or potential threat to human health or environment, which include endocrine disruptors, pharmaceutical, personal care products, nanoparticles, antibiotic resistance genes and chemicals used in packaging products, etc. The disposal and treatment of emerging contaminants has become a key problem in the field of water pollution control. The purpose of this review is to summarize published researches on emerging pollutants treatment in 2015. [ABSTRACT FROM AUTHOR]

Emerging contaminants are considered as some substances of actual or potential threat to human health or environment, which include endocrine disruptors, pharmaceutical, personal care products, nanoparticles, antibiotic resistance genes and chemicals used in packaging products, etc. The disposal and treatment of emerging contaminants has become a key problem in the field of water pollution control. The purpose of this review is to summarize published researches on emerging pollutants treatment in 2014. [ABSTRACT FROM AUTHOR]

Abstract: Fe3O4 nanoparticles were prepared by carbothermal reduction method using glucose as carbon source. Heating temperature and holding time effects on crystalline phase composition and magnetic properties of Fe3O4 nanoparticles were investigated by X-ray diffraction, field-emission scanning electron microscopy and vibrating sample magnetometer. Pure Fe3O4 nanoparticles with an average crystallite size of 48nm was obtained at higher heating temperature of 650°C and shorter holding time of 0.5h, or at lower heating temperature of 450°C and longer holding time of more than 6h. The crystallite size of Fe3O4 nanoparticles increases with heating temperature and holding time. Fe3O4 nanoparticles heated at 650°C for 2h have the highest saturation magnetization (M s =97.99emug−1), higher than Fe3O4 prepared by other techniques due to better microstructure, crystallinity and expanded crystalline cell. [ABSTRACT FROM AUTHOR]

Abstract: Ferromagnetic SmCo nanoparticles with narrow size distribution (5–8nm) were successfully prepared by polyol co-reduction using non-toxic inorganic precursors (nitrates) instead of deadly poisonous organometallic precursors (acetylacetonate or carbonyl compounds). In the synthesis, Sm3+ and Co2+ can get electrons from acetaldehyde (CH3CHO) and then are reduced to Sm and Co. However, the standard electrode potential of Sm3+ is far lower than that of Co2+ so that Co2+ is reduced early and then grow up quickly. The additive of CH3COOH increases the concentration of H+ and decreases the stability of Sm3+, which results in the co-reduction of the Co2+ and Sm3+. So the SmCo nanoparticles are synthesized in-situ. The coercivity and magnetization of the nanoparticles were 1041Oe and 55emu/g, respectively. [Copyright &y& Elsevier]

This paper proposes a new method for producing nano-SrFe12O19 powder by the citrate precursor route using solid waste as a source of iron. This solid iron-containing waste, which exists in the form of an oily sludge, is produced by a cold rolling mill. This sludge was first subjected to a process, including sulfuric acid leaching, oxidation, precipitation, and nitric acid leaching, to obtain an iron nitrate (Fe(NO3)3) solution. Next, the Fe(NO3)3 solution was mixed with a strontium nitrate (Sr(NO3)2) solution obtained by subjecting strontium carbonate to nitric acid leaching. Subsequently, citric acid, as chelating agent, and ammonia water, as precipitating agent, were added to the mixed solution to form a gel. The gel was dried and spontaneously combusted, then annealed at different temperatures for 2 h in flowing air. The effects of the Fe3+/Sr2+ molar ratio and annealing temperature on the formation, morphology, and magnetic properties of SrFe12O19 were investigated. The results showed that single-phase SrFe12O19 powder was obtained by decreasing the Fe3+/Sr2+ molar ratio from the stoichiometric value of 12 to 11.6 and increasing the annealing temperature to 1000 °C for 2 h. Adjustment of the Fe/Sr molar ratio to 12 and the annealing temperature to 900 °C enabled the magnetic properties to be optimized, including saturation magnetization (Ms) 80.2 emu/g, remanence magnetization (Mr) 39.8 emu/g, and coercive force (Hc) 6318 Oe. [ABSTRACT FROM AUTHOR]

Abstract: Using spent alkaline Zn–Mn batteries as raw material, Mn–Zn soft magnetic ferrite nanoparticles are prepared by multi-step processes including acid leaching, chemical treatment of battery iron shells and citrate-nitrate precursor auto-combustion. Acid leaching and chemical treatment mechanisms are investigated. Dried gels thermal decomposition process, auto-combustion, phase composition, morphological and magnetic properties of as-prepared Mn–Zn ferrite nanoparticles are characterized by thermogravimetric and differential thermal analysis, X-ray powder diffraction, transmission electron microscopy and vibrating sample magnetometer. Synthesized Mn–Zn ferrite nanoparticles (Mn0.5Zn0.5Fe2O4) have pure ferrite phase, larger saturation magnetization (M s =60.62emug−1) and lower coercivity (H c =30Oe) compared with the same composition ferrites prepared by other techniques due to better crystallinity. Mn–Zn ferrite nanoparticles synthesis method presents a viable alternative for alkaline Zn–Mn batteries recycling. [Copyright &y& Elsevier]