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121.
《Nuclear Physics B》1999,556(3):485-504
We derive the exchange relations of the vertex operators of Uq(A2(2)) and show that these vertex operators give the bosonization of the Izergin-Korepin model. We give an integral expression of the correlation functions of the Izergin-Korepin model and derive the difference equations which they satisfy. 相似文献
122.
Carbon dioxide (CO2) is regarded as a main contributor to the greenhouse effect. As a potential strategy to mitigate its negative impacts, the reduction of CO2 is environmentally critical, economically meaningful and scientifically challenging. Being both thermodynamically and kinetically unfavored, CO2 reduction requires catalysts as a crucial component irrespective of the reaction modes, be it electrocatalytic, photoelectrocatalytic or photocatalytic. In an effort to systematically review the types of catalysts that have been studied for CO2 reduction, we categorize them into two major groups: those being activated by external sources and those being photoexcited and activated themselves. Attention is focused on the detailed mechanisms for each group by which the reduction of CO2 proceeds, yielding a summary of the guiding principles for catalyst designs. This review highlights the importance of mechanistic studies, which permits us to discuss our perspectives on potential directions of catalyst investigation for future catalytic CO2 reduction research. 相似文献
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Wenzhen GanZhigui Lin 《Applied Mathematical Modelling》2012,36(3):989-996
This paper deals with a two species model with Schoener’s competitive interaction. The existence and the asymptotic behavior of T-periodic solutions for the periodic system of quasilinear parabolic equations under nonlinear boundary conditions are given by using upper and lower solutions and corresponding iteration. The numerical simulations are also presented to illustrate our result. It is shown that periodic solutions may exist if the inter-specific competition rates are weak. 相似文献
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127.
刘建忠 《数学物理学报(A辑)》2012,32(1):171-185
利用H\"{o}lder不等式和β-函数, 得到了Hardy-Littlewood不等式的一些推广和改进形式. 作为应用, 通过所得结果及矩阵方法, 给出了Hilbert型不等式的一些推广和改进. 相似文献
128.
Xue-fen?XuEmail author Ye-jun?Xu Hong-yi?Fan 《International Journal of Theoretical Physics》2012,51(6):1753-1761
Dirac is the founder of quantum mechanical representation theory. By virtue of the technique of integration within an ordered
product (IWOP) of operators we introduce s-parameterized form of quantum mechanical coordinate and momentum representations, which are complete. We then point out that
s-parameterized representation’s completeness relation is accompanied with operators’ s-ordering, the special cases s=1,0,−1 correspond to normal-ordering, Weyl ordering and antinormal-ordering, respectively. The s-parameterized form of the coherent state representation and the entangled state representation are also derived. In our view,
the operators’ s-ordering should be traced back to s-parameterized form of the completeness relation of quantum mechanical coordinate and momentum representations, which is more
fundamental. Many operator identities can be derived by virtue of the above mentioned s-parameterized representation’s completeness relations. 相似文献
129.
Wei-Der Chang 《Chaos, solitons, and fractals》2009,39(2):910-917
In this paper, we attempt to use the proportional-integral-derivative (PID) controller to achieve the chaos synchronization for delayed discrete chaotic systems. Three PID control gains can be optimally determined by means of using a novel optimization algorithm, called the particle swarm optimization (PSO). The algorithm is motivated from the organism behavior of fish schooling and bird flocking, and involves the social psychology principles in socio-cognition human agents and evolutionary computations. It has a good numerical convergence for solving optimization problem. To show the validity of the PSO-based PID control for chaos synchronization, several cases with different initial populations are considered and some simulation results are shown. 相似文献
130.
利用Fourier级数理论,伯努利数理论和重合度理论研究了一类具偏差变元的高阶泛函微分方程$x^{(m)}(t)+\beta (t)g(x(t-\tau(t)))=p(t)$的周期解问题,得到了周期解存在性的新结论,有意义的是非线性项前的系数$\beta(t)$可变号,但是,周期解先验界估计方法与已有工作不同. 相似文献