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LiNiO2 cathode material for lithium-ion batteries has the advantages of high specific capacity, abundant resources, and low cost, but it suffers from difficulties in preparation, structural instability, and serious capacity decay. In this work, highly pure and layered structural LiNi0.95 Ala Ti0.05-a O2 (a=0, 0.025, 0.05) cathode materials were synthesized by a simply sol-gel method. The cation mixing of Ni2+ and Li+ , structural deterioration, irreversible conversion between H2 and H3 phases and unstable surface and CEI (Cathode-electrolyte interface) film can be effectively suppressed by co-doping with Al3+ and Ti4+ . A preferred LiNi0.95 Al0.025 Ti0.025 O2 sample provides a discharge specific capacity of 223â mAh g-1 at 0.1â C and 148.32â mAh g-1 at 5â C, a capacity retention of 72.7 % after 300â cycles at 1â C and a Li+ diffusion coefficient of about 2.0×10-9 cm2 s-1 .
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Lithium-sulfur (Li-S) batteries show great potential in future electric transportation and large-scale grid storage applications because of their attractive theoretical energy density (2600 W h kg-1) and relatively abundant sulfur reserves. However, the rapid capacity decay and unsatisfactory sulfur loading caused by the lithium polysulphide (LiPS) dissolution and low electrical conductivity of sulfur are the most urgent issues plaguing its practical applications. Herein, we report a multifunctional nanoporous (NP) VN/V2O5 binary host that can efficiently resolve the above conflicts by the synergy between the functions of two materials. The inner V2O5 facilitates rapid trapping of numerous LiPSs while the outer porous VN with abundant NP channels offers high conductivity and mild chemisorption, thereby improving the localization and catalytic conversion ability of LiPSs. Accordingly, the designed cathodes with 1.87 mg cm-2 sulfur content achieve an acceptable areal specific capacity (2.72 mA h cm-2), excellent rate capability (963 mA h g-1 at 5.0C), and cycling stability. Remarkably, the cathodes with ultrahigh sulfur loading of 9.02 mg cm-2 deliver a satisfactory areal specific capacity (12.12 mA h cm-2) and still maintain excellent durability.
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The electrochemical performances and process mechanisms of Zn/LiFePO4 cells in a slightly acidic 1.9â m Li2 SO4 -0.5â m ZnSO4 aqueous solution were investigated. The results showed that the hydrogen depletion side reaction on the surface of the zinc sheet led to an increase in pH of the electrolyte and fluctuations in specific capacity of the cells, and that the dissolution of Fe2+ ions and the lamination of LiFePO4 particles resulted in a decrease in the specific capacity of the cells. At pHâ 5.0, the initial discharge specific capacity of the Zn/LiFePO4 cell was about 120.0â mAh g-1 at 0.25â C, about 64.4â mAh g-1 at 3â C, with about 60.9 % capacity retention rate after 200 cycles at 1â C, and the Li+ ions diffusion coefficient was about 7.75×10-12 â cm2 s-1 .
Assuntos
Fontes de Energia Elétrica , Eletrólitos , Íons , Lítio , Água , ZincoRESUMO
Recycling Zn and Fe from jarosite residue to produce high value-added products is of great importance to the healthy and sustainable development of zinc industry. In this work, we reported the preparation of ZnFe2O4/α-Fe2O3 nanocomposites from the leaching liquor of jarosite residue by a facile chemical coprecipitation method followed by heat treatment at 800°C in air. The microstructure of the as-prepared ZnFe2O4/α-Fe2O3 nanocomposites were characterized by X-ray diffraction (XRD), Mössbauer spectroscopy, scanning transmission electron microscope (STEM), and X-ray photoelectron spectrum (XPS). The results demonstrated that the ZnFe2O4/α-Fe2O3 composites are composed of interconnected ZnFe2O4 and α-Fe2O3 nanocrystals with sizes in the range of 20-40 nm. When evaluated as anode material for Li-ion batteries, the ZnFe2O4/α-Fe2O3 nanocomposites exhibits high lithium storage activity, superior cyclic stability, and good high rate capability. Cyclic voltammetry analysis reveals that surface pseudocapacitive lithium storage has a significant contribution to the total stored charge of the ZnFe2O4/α-Fe2O3, which accounts for the enhanced lithium storage performance during cycling. The synthesis of ZnFe2O4/α-Fe2O3 nanocomposites from the leaching liquor of jarosite residue and its successful application in lithium-ion batteries open up new avenues in the fields of healthy and sustainable development of industries.
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PURPOSE: This study aimed to predict the outcome of urinary cadmium (Cd) excretion and renal tubular function by analyzing their evolution through 10 years after Cd exposure ceased. METHODS: Forty-one female, non-smoking workers were recruited from the year 2004 to 2009 when being removed from a nickel-cadmium battery factory, and they were asked to provide morning urine samples on three consecutive days at enrollment and in every follow-up year until 2014. Urinary Cd and renal tubular function biomarkers including urinary ß2-microglobulin (ß2-m) and retinol-binding protein (RBP) concentrations were determined with the graphite furnace atomic absorption spectrometry and the enzyme-linked immunosorbent assays, respectively. RESULTS: The medians of baseline Cd, ß2-m and RBP concentrations at enrollment were 6.19, 105.38 and 71.84 µg/g creatinine, respectively. Urinary ß2-m and RBP concentrations were both related to Cd concentrations over the years (ß absolute-ß2-m = 9.16, P = 0.008 and ß absolute-RBP = 6.42, P < 0.001, respectively). Cd, ß2-m and RBP concentrations in the follow-up years were all associated with their baseline concentrations (ß absolute-Cd = 0.61, P < 0.001; ß absolute-ß2-m = 0.64, P < 0.001; and ß absolute-RBP = 0.60, P < 0.001, respectively), and showed a decreasing tendency with the number of elapsed years relative to their baseline concentrations (ß relative-Cd = -0.20, P = 0.010; ß relative-ß2-m = -17.19, P = 0.002; and ß relative-RBP = -10.66, P < 0.001, respectively). CONCLUSIONS: Urinary Cd might eventually decrease to the general population level, and Cd-related tubular function would improve under the baseline conditions of this cohort.
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Cádmio/toxicidade , Cádmio/urina , Túbulos Renais/metabolismo , Indústria Manufatureira , Exposição Ocupacional/efeitos adversos , Adulto , Biomarcadores/urina , Creatinina/urina , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Túbulos Renais/efeitos dos fármacos , Estudos Longitudinais , Níquel/toxicidade , Proteínas de Ligação ao Retinol/urina , Espectrofotometria Atômica/métodos , Microglobulina beta-2/urinaRESUMO
Cannabis sativa has long been used as a traditional medicine in China. Among its effective compounds are cannabinoids. This study determined the effect of WIN55,212-2 (WIN), a synthetic cannabinoid, on the BEL-7402 human hepatocellular carcinoma (HCC) cell line. The results showed that WIN could decrease the proliferation of BEL-7402 cells. Moreover, WIN could cause apoptosis of the cells via up-regulation of Bax expression, down-regulation of Bcl-2 expression, induction of the mitochondrial membrane potential, increase of caspase-3, -8 and -9 activities, and induction of the cleavage of caspase-3 and poly-ADP-ribose polymerase (PARP). The WIN-induced apoptosis was accompanied by the up-regulation of PPARγ expression, the activation of PPARγ DNA binding activity, and a down-regulation of PPARγ target oncogene c-myc. Conversely, the effects of WIN could be attenuated by PPARγ antagonist GW9662, and the WIN induced PPARγ expression was partially attenuated by AM630, a cannabinoid receptor-2 antagonist, whereas the WIN-induced reduction of c-myc expression was partially restored by GW9662. Collectively, our results suggest that WIN can decrease the proliferation and cause apoptosis of the BEL-7402 cells via a mitochondrial-caspase pathway and mediated by PPARγ. These results may provide a basis for the application of WIN in HCC treatment.