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191.
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We study the inhomogeneous deformation of a wedge of an incompressible generalized power-law Neo-Hookean material. We find solutions which have a boundary layer structure, in the sense that adjacent to the boundary the solution is inhomogeneous, while in the core region the solution is homogeneous. It is found that such solutions have an associated pressure field that is bounded. Inhomogeneous solutions are also possible when the pressure varies logarithmically with the radial coordinate. We also establish explicit exact solutions for specific values of the parameter. The results reduce to the Neo-Hookean solution when the power law exponent is set to unity. 相似文献
195.
钽离子掺杂对LiFePO4 / C物理和电化学性能的影响 总被引:2,自引:0,他引:2
采用PAM(聚丙烯酰胺)模板-溶胶凝胶法在惰性气氛下合成钽掺杂的LiFePO4/C复合正极材料,考察了钽对目标化合物的物理和电化学性能的影响。研究结果表明,0.33C的电流下充放电时,掺杂前后第2个循环的放电容量分别为138.6 mAh·g-1和155.5 mAh·g-1,循环20次后容量为141 mAh·g-1和156 mAh·g-1。电化学交流阻抗表明,掺杂后的材料阻抗Rct从180 Ω减小到120 Ω。振实密度比掺杂前提高0.312 g·cm-3。 相似文献
196.
197.
Surfactant molecules containing hydrophobic long alkyl chains and hydrophilic groups can organize into various micellar structures both in bulk solution and at interface. However, because of the dynamical nature of surfactant micelles, efforts directed at fixing their structures in bulk solution by polymerization have met with limited success. Herein, we report a unique and simple method of stabilizing surface micelles of a low molecular weight surfactant 11-acryloyloxyundecyltriethylammonium bromide (AUTEAB) through in situ intramicellar polymerization on the mica surface. Atomic force microscopy (AFM) observations show that the cylindrical micellar structure formed by AUTEAB monomers at the mica/water interface is preserved after the in situ polymerization, and the stability of the polymerized surface micelles is greatly enhanced compared with that of the unpolymerized ones. 相似文献
198.
Synthesis, Structure and Conductivity of the New Charge-transfer Salt (ET)_2(CH_2=CH-CH_2-SO_3)·H_2O
Zhi LIU Qi FANG* Wen Tao YU Min Hua JIANG De Qing ZHANG Dao Ben ZHU State Key Laboratory of Crystal Materials Shandong University Jinan Institute of Chemistry The Chinese Academy of Sciences Beijing 《中国化学快报》2003,14(4)
ET is one of the most famous electron-donor molecules, which forms charge-transfer complexes (abbr. CT-complexes) with various types of counterions. These complexes have received intense attention because a wide range of physical properties such as conductivity and superconductivity1, ferromagnetism2-4 and nonlinear optical properties5 was found in these materials. Although the majority of the ET-based CT-complexes were prepared by combining with inorganic counterions, CT-complexes with o… 相似文献
199.
A novel molecular entity vacancy model was proposed to describe thermodynamic properties in a multicomponent solution system using its binary interaction parameters only. A derivation of the model for its general expression has been shown in detail. Under some special conditions, this model may be reduced to Flory–Huggins equation, Wilson equation and non-random two liquids (NRTL) equation as well as molecular interaction volume model (MIVM), respectively, and can be verified by Gibbs–Duhem equation, and can express thermodynamic properties of partially miscible systems. The predicted activities are in good agreement with experimental data of some liquid alloys. The results show that the model is of better predictability and reliability because it has a certain physical basis. 相似文献
200.
A series of spiropyrans with a polyaromatic or heteroaromatic pendant was synthesized conveniently.Their photochromic behaviors were investigated with the aid of absorption spectral measurements.The results indicated that the compounds with the same parent spiropyran but different aromatic pendant show significantly different photochromic properties.This may be due to the π-π orbital interaction between the polyaromatic pendant and the open photomerocyanine form of spiropyran.The results obtained are very useful in the molecule design area. 相似文献