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排序方式: 共有149条查询结果,搜索用时 15 毫秒
111.
Using a computerized symbolic computation technique, a new method named the Repeated General Algebraic Method (RGAM) is established in this study in order to find exact solutions of Nonlinear Partial Differential Equations (NLPDEs). The new method is validated based on the (2+1)-dimensional Broer-Kaup-Kupershmidt (BKK) equations. By using the RGAM in various conditions, a number of exact solutions of NLPDEs have been obtained showing potential importance in future physical applications. Also, it is anticipated that the RGAM can be applied to other nonlinear evolution equations in mathematical physics to produce some interesting outcomes.  相似文献   
112.
By means of a special variable separation approach, a common formula with two arbitrary functions has been obtained for suitable physical quantity of (1+1)-dimensional model such as Boiti-Leon-Pempinelli-Spire system. Based on the derived formula, some significant types of solitons such as compacton, peakon, and loop solutions localized in space and periodical in time are simultaneously constructed from the (1+1)-dimensional soliton system by entrancing appropriate piecewise smooth functions and multivalued functions.  相似文献   
113.
担载Ag对TiO2界面光生电子转移效率的影响   总被引:8,自引:0,他引:8  
通过采用原位电子顺磁共振(EPR)、紫外-可见漫反射(DRS)、低温液氮吸附技术对光化学还原法合成Ag/TiO2进行表征,比较不同反应气氛,Fe3+为电子受体及微量H2O2存在情况下TiO2和Ag/TiO2光催化活性变化,阐述了Ag担载对TiO2界面光生电子的传输与捕获效率的影响. Ag捕获的光生电子具有较强流动性,可迅速向Ag/TiO2表面吸附的O2分子或表面Ti4+传递,在Ag表面产生活性物种或在TiO2表面生成活性反应中心表相Ti3+,减少光生电子在TiO2的体内俘获生成复合中心即体相内部Ti3+的几率.适宜尺寸纳米Ag团簇的担载可有效加速光生电子的传输与捕获效率,提高活性物种数量.  相似文献   
114.
张义权  罗成林  余智 《无机化学学报》2002,18(11):1147-1150
Magnetic coupling constants J between Cu ions and spin density map for a binuclear complex Cu2(2,2′-bpy)2(4,4′-bpy)2L2 have been calculated by the combination of the broken symmetry approach with the spin project method under the DFT framework and the effect of nonorthogonality between magnetic α and β orbitals in the broken symmetry solution. The result indicates that using SV/SVP basis sets in the calculation of Gaussian 98 is much better than using LanL2DZ pseudo-potential function in above system. It is interesting that calculated J value is quite near to the experimental value in the studies of magnetic susceptibility.  相似文献   
115.
Solid-state electrolytes (SSEs) with high ionic conductivity and superior stability are considered to be a key technology for the safe operation of solid-state lithium batteries. However, current SSEs are incapable of meeting the requirements for practical solid-state lithium batteries. Here we report a general strategy for achieving high-performance SSEs by engineering polymers of intrinsic microporosity (PIMs). Taking advantage of the interconnected ion pathways generated from the ionizable groups, high ionic conductivity (1.06×10−3 S cm−1 at 25 °C) is achieved for the PIMs-based SSEs. The mechanically strong (50.0 MPa) and non-flammable SSEs combine the two superiorities of outstanding Li+ conductivity and electrochemical stability, which can restrain the dendrite growth and prevent Li symmetric batteries from short-circuiting even after more than 2200 h cycling. Benefiting from the rational design of SSEs, PIMs-based SSEs Li-metal batteries can achieve good cycling performance and superior feasibility in a series of withstand abuse tests including bending, cutting, and penetration. Moreover, the PIMs-based SSEs endow high specific capacity (11307 mAh g−1) and long-term discharge/charge stability (247 cycles) for solid-state Li−O2 batteries. The PIMs-based SSEs present a powerful strategy for enabling safe operation of high-energy solid-state batteries.  相似文献   
116.
微型能源存储器件在可穿戴电子产品、微型自驱动探测器等领域有重要的应用前景,同时为研究储能器件电极结构、电子/离子传导率以及电化学动力学之间的内在联系提供了理想的平台。自卷曲技术是利用材料内部存在的残余应力而实现二维薄膜材料自行弯曲的一种方法。相比于传统微纳制备工艺,这种方法可以在微米尺度下将二维薄膜电极材料有序卷曲排列,为微型储能器件的制备提供了有效、便捷的途径。本文介绍了近些年自卷曲技术在微型能源存储器件上的重要进展,其中包括材料自卷曲的原理、自卷曲电极及其储能性质,并以此为基础,着重阐述了自卷曲技术制备单根管微型锂离子电池和电容阵列的应用实例。总结并展望了自卷曲技术在微型储能器件应用上的未来挑战和重要机遇。  相似文献   
117.
This paper presents a new and efficient approach for constructing exact solutions to nonlinear differential--difference equations (NLDDEs) and lattice equation. By using this method via symbolic computation system MAPLE, we obtained abundant soliton-like and/or period-form solutions to the (2+1)-dimensional Toda equation. It seems that solitary wave solutions are merely special cases in one family. Furthermore, the method can also be applied to other nonlinear differential--difference equations.  相似文献   
118.
In this paper, the direct symmetry method is extended to the Lax pair of the ANNV equation. As a result, symmetries of the Lax pair and the ANNV equation are obtained at the same time. Applying the obtained symmetry, the (2+1)-dimensional Lax pair is reduced to (1+1)-dimensional Lax pair, whose compatibility yields the reduction of the ANNV equation. Based on the obtained reductions of the ANNV equation, a lot of new exact solutions for the ANNV equation are found. This shows that for an integrable system, both the symmetry and the reductions can be obtained through its corresponding Lax pair.  相似文献   
119.
陈元正  周密  孙美娇  里佐威  孙成林 《中国物理 B》2014,23(2):23302-023302
The pressure-induced molecular dissociation as one of the fundamental problems in physical sciences has aroused many theoretical and experimental studies. Here, using a newly developed particle swarm optimization algorithm, we investigate the high-pressure-induced molecular dissociation. The results show that the carbon tetrachloride (CC14) is unstable and dissociates into C2C16 and C12 under approximately 120 GPa and more. The dissociation is confirmed by the lattice dynamic calculations and electronic structure of the Pa3 structure with pressure evolution. The dissociation pressure is far larger than that in the case of high temperature, indicating that the temperature effectively reduces the activation barrier of the dissociation reaction of CC14. This research improves the understanding of the dissociation reactions of CC14 and other halogen compounds under high pressures.  相似文献   
120.
A generalized variable-coefficient algebraic method is applied to construct several new families of exact solutions of physical interestfor (3 1)-dimensional Kadomtsev-Petviashvilli (KP) equation. Among them, the Jacobi elliptic periodic solutions exactly degenerate to the soliton solutions at a certain limit condition. Compared with the existing tanh method, the extended tanh method, the Jacobi elliptic function method, and the algebraic method, the proposed method gives new and more general solutions.  相似文献   
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