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221.
Jiangang Li Xiangming He Maosong Fan Rusong Zhao Changyin Jiang Chunrong Wan 《Ionics》2006,12(1):77-80
Spherical LiNi1/3Co1/3Mn1/3O2 was successfully prepared by controlled crystallization. The preparation started with the spherical coprecipitate of Ni1/3Co1/3Mn1/3CO3 from NiSO4, CoSO4, MnSO4, NH4HCO3, and NH3·H2O, followed by pyrolysis of Ni1/3Co1/3Mn1/3CO3 at 600°C for 3 h. The X-ray diffraction analysis showed that the homogeneous cubic (Ni1/3Co1/3Mn1/3)3O4 was obtained after the pyrolysis. Spherical LiNi1/3Co1/3Mn1/3O2 was obtained by sintering of the mixture of as-obtained (Ni1/3Co1/3Mn1/3)3O4 and LiOH·H2O at 900°C for 6 h in air. As-prepared spherical LiNi1/3Co1/3Mn1/3O2 presented initial discharge capacity of 162.9 mA h g−1 and capacity retention of 98% at 50th cycle. 相似文献
222.
从计算得出的浮动上模作往复周期摆动时工件表面上任一点的相对线速度表达式看出,线速度幅值是一个多变量函数,在这些参数中,只有主轴转速与摆架摆速是机床本身的固有参数,从均匀抛光角度出发,提出主轴转速与摆架摆速匹配的观点,为抛光机换代设计提供了依据。 相似文献
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225.
利用电子束蒸发方法,在不同沉积温度(50~350℃)下制备了Sc2O3薄膜。分别用分光光度计,小角掠入射X射线衍射仪和轮廓仪测试了薄膜样品的光谱、微结构和表面粗糙度信息,并用薄膜分析软件Essential Macleod计算了Sc2O3薄膜的折射率和消光系数。结果表明:随着沉积温度升高,Sc2O3薄膜结晶程度增强,晶粒尺寸增大,且较高的沉积温度有利于获得较高的折射率。最后用355 nm,8 ns的三倍频Nd:YAG激光器测试了其激光损伤阈值(LIDT),最大值为2.6 J/cm2,且阈值与薄膜的消光系数、表面粗糙度、光学损耗均呈现相反的变化趋势。用光学显微镜和扫描电子显微镜表征了该薄膜的破坏形貌,详细分析了薄膜在不同激光能量作用下破坏的发展过程,以及Sc2O3薄膜在355 nm紫外激光作用下LIDT与制备工艺的关系,重点分析了355 nm激光作用下薄膜的破坏机理。 相似文献
226.
Nanocrystalline cobalt ferrites were synthesized by a simple, general, one-step sol–gel auto-combustion method. An interpretation based on the measurement of the adiabatic flame temperature and the amounts of gas evolved during reaction had been proposed for the nature of combustion. The influence of annealing temperatures on the magnetic properties was investigated. The microstructure was characterized by means of X-ray diffractometer (XRD) and transmission electron microscopy (TEM). It was found that the particle size and magnetic properties of the as-prepared ferrite samples showed strong dependence on the annealing temperature. The coercivity initially increased and then decreased with increasing annealing temperature whereas the particle size and saturation magnetization continuously increased. 相似文献
227.
Hepatitis C virus (HCV) is a pathogen that is of great medical significance in chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma worldwide. Although the HCV proteins have been intensively investigated over the past decade, the biochemical functions of the NS4B protein are still largely unknown. To investigate NS4B as a potential causative agent of liver disease, transgenic mice expressing the NS4B protein in liver tissue were produced. The transgenic animals were phenotypically similar to their normal littermates for up to 18 months of age. Our results suggest that the HCV NS4B protein is not directly cytopathic or oncogenic in our transgenic mice model. 相似文献
228.
Spring-like superstructures consisting of layered tin(IV) hydrogen phosphate nanodisks can be obtained via a one-pot solvothermal reaction of tin tetrachloride and phosphoric acid in ethanol. These superstructures are active anode materials for the lithium-ion battery. 相似文献
229.
Xiangshun Kong Mingyao Ai Kwok Leung Tsui 《Annals of the Institute of Statistical Mathematics》2018,70(3):631-646
Sliced Latin hypercube designs are popularly adopted for computer experiments with qualitative factors. Previous constructions require the sizes of different slices to be identical. Here we construct sliced designs with flexible sizes of slices. Besides achieving desirable one-dimensional uniformity, flexible sliced designs (FSDs) constructed in this paper accommodate arbitrary sizes for different slices and cover ordinary sliced Latin hypercube designs as special cases. The sampling properties of FSDs are derived and a central limit theorem is established. It shows that any linear combination of the sample means from different models on slices follows an asymptotic normal distribution. Some simulations compare FSDs with other sliced designs in collective evaluations of multiple computer models. 相似文献
230.
In this paper, we study the existence, uniqueness and the probabilistic representation of the weak solutions of quasi-linear parabolic and elliptic partial differential equations (PDEs) in the Sobolev space . For this, we study first the solutions of forward–backward stochastic differential equations (FBSDEs) with smooth coefficients, regularity of solutions and their connection with classical solutions of quasi-linear parabolic PDEs. Then using the approximation procedure, we establish their convergence in the Sobolev space to the solutions of the FBSDES in the space . This gives a connection with the weak solutions of quasi-linear parabolic PDEs. Finally, we study the unique weak solutions of quasi-linear elliptic PDEs using the solutions of the FBSDEs on infinite horizon. 相似文献