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AbstractA lamellar zinc dimolybdate hydroxide Zn3Mo2O8(OH)2 was prepared for the first time by a facile hydrothermal synthesis. The electrochemical properties of the lamellar Zn3Mo2O8(OH)2 as an anode material were investigated by cyclic voltammetry (CV), reversible capacity, cycling stability and rate capability for lithium ion batteries (LIB). The lamellar zinc dimolybdate hydroxide exhibits a reversible capacity of 404.6 mAh g?1 at a current density of 100?mA g?1 after 200 cycles. The reversible capacity of the lamellar Zn3Mo2O8(OH)2 remained at 60 mAh g?1 even at a current density of 3000?mA g?1. When the current density was returned to 100?mA g?1, a discharge capacity of 380 mAh g?1 was maintained after 200 discharge/charge cycles. The excellent electrochemical performance may be due to its unique lamellar structure, which buffers the volume change during the Li+ intercalation/de-intercalation and provides the electrode with convenient lithium ions and electron transport pathways. These results suggest the promising potential application of the lamellar zinc dimolybdate hydroxide in lithium-ion batteries. 相似文献
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《稀有金属材料与工程》2018,35(5):20-23
为研究具有原始粗片层组织的Ti5321合金热压缩变形过程中流变应力、显微组织等随变形条件的变化,在Gleeble-2800型热模拟试验机上进行高温热压缩试验,试验温度790~850 ℃,应变速率为0.01~1 s-1,变形量为30%~70%。结果表明:Ti5321合金的软化机制与片层组织球化和动态再结晶有关,变形量和变形温度是影响合金片层组织球化及β再结晶的主要因素。同一变形温度和应变速率下,随着变形量的增大.会出现片层α相球化及β相再结晶现象。当应变速率和变形量相同时,低温变形主要发生的是片层α相球化行为,高温变形发生的是β相的再结晶。 相似文献
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Cast films, based on polypropylene (PP), were prepared via melt extrusion and, then, annealed below the melting temperature. The effect of annealing conditions on the properties of the films and the microporous membranes formed by stretching was investigated. It is shown that annealing is an effective method to improve the physical properties of semi-crystalline polymers by promoting chain rearrangement and creating secondary lamellae in the amorphous region. DSC results for annealed samples revealed the appearance of a shoulder endothermic peak and a new peak in the correlation function from the SAXS patterns was observed. The annealed films exhibited double yield points in the tensile deformation curves. A direct linear relationship was found between the strength of the second yield point and the fraction of the lamellae. From mercury porosimetry and SEM images of the membranes larger pore sizes and porosity were observed as the annealing time and temperature increased. 相似文献
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Flexible polyurethane foams are widely used in cushioning and packaging applications. A model for the dynamics of formation of polyurethane foams is presented, which includes thinning of foam lamellae. Experimental measurements for water blown flexible foam formulations at different water concentrations are presented to validate the model. Adiabatic temperature rise measurements during foaming are used to obtain the kinetic parameters of the reactions of isocyanate with polyol and water. The variation of foam density during foaming is studied by weight loss and video shooting methods and both are compared to estimate the amount of blowing gas lost during foaming. The average thickness of the foam lamellae of the solid foam is obtained by SEM measurements. The predictions of the model show good agreement with the experimental measurements of temperature and density with time and the final lamellar thickness. The results are important for understanding the cell opening process. © 2009 American Institute of Chemical Engineers AIChE J, 2010 相似文献
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Chen Hui Su Yanqing Luo Liangshun Li Xinzhong Wang Zhantao GuoJingjie Fu Hengzhi 《中国铸造》2012,9(2):108-113
The fracture behavior of fully lamellar binary γ-TiAl alloys is extremely anisotropic with respect to the lamellar orientation.For the fully lamellar Ti-46Al-0.5W-0.5Si alloy,the existence of silicide ... 相似文献
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利用等径角挤压法ECAP(EqualChannelAngularPressing)对具有超细共析片层结构的Zn-22%Al(质量分数,下同)合金进行8道次变形,大部分片层转变为双相等轴晶,晶粒尺寸约为1.6μm。该转变发生是由于ECAP过程中材料承受剪切应变,应变能累积诱发再结晶,从而形成等轴晶双相结构。这与片层结构经以施加正应变为主的传统压力加工方法处理所获得的微观组织有显著区别。 相似文献
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