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41.
The structure and phase transition of a two-dimensional (2D) dusty plasma have been investigated in detail by molecular dynamics simulation. Pair correlation function, static structure factor, mean square displacement, and bond angle correlation function have been calculated to characterize the structural properties. The variation of internal energy, shear modulus, particle trajectories and structural properties with temperature has been monitored to study the phase transition of the 2D dusty plasma system. The simulation results are in favour of a two-step continuous transition for this kind of plasma. 相似文献
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Structure of Multi-Species Charged-Particles with Competing Interactions in a Quadratic Trap 下载免费PDF全文
Multi-species charged-particles interacting with each other by a competing short-range attraction and long-range repulsion potential confined in a quadratic trap are studied with molecular dynamics simulations. It is found that particles with similar mass-to-charge ratio tend to populate a common shell, whose location depends on the particle mass-to-charge ratio, and that the greater the latter is, the closer the particles to the centre of the trap are. This rule for the ground-state configuration is independent of the total particle and species numbers in the system. 相似文献
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DECAY RATES AND CONVERGENCE OF SOLUTIONS TO SYSTEM OF ONE-DIMENSIONAL VISCOELASTIC MODEL WITH DAMPING 总被引:1,自引:0,他引:1
This paper considers the asymptotic behavior of solutions to the system of onedimensional viscoelastic model with damping and prove that the corresponding solutions time-asymptotically behave like nonlinear diffusion wave as in [4,11]. In addition, It is also shown that the system of one-dimensional viscoelastic model with damping is a viscosity approximation of a hyperbolic conservation laws with damping. 相似文献
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利用隧穿机制研究了含磁光金属Co6Ag94的三明治结构(磁光金属嵌入两个磁光光子晶体中)的透射性质和磁光法拉第旋转效应。在含磁光金属的三明治结构中,分别研究了双透射峰和单透射峰两种情况。研究结果表明,无论是双透射峰还是单透射峰情况,局域在磁光金属和磁光光子晶体界面上的电磁场,都能够同时增强磁光金属的透射和磁光法拉第旋转效应。另外,分析了磁光金属Co6Ag94存在增益时该三明治结构法拉第旋转角达到-45°的情况,此性质为设计小型化的磁光隔离器件提供了理论依据。 相似文献
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Influence of Defect Particles on Configuration of a Two-Dimensionally Confined Dusty Plasma 下载免费PDF全文
The behaviour of defect particles in a two-dimensional (2D) confined dusty plasma system is investigated by molecular dynamics (MD) simulations. The mean square displacement (MSD) and the pair correlation function g(r) are used to characterize the structural and dynamical properties of the system. The influences of the number and the charge (mass) of the defect particles on the system configurations are simulated. All the defect particles with charges (masses) larger than the normal particles have the trend to move towards the system centre. The moving speed of the defect particles towards the centre increases with the increasing number and charge (mass) of defect particles and with the system temperature. 相似文献
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环丙沙星荷移反应及荧光光谱性质研究 总被引:6,自引:0,他引:6
研究了环丙沙星(CPFX)与电子受体2,3-二氰-5,6-二氯-1,4对苯酯(DDQ)之间的荷移反应。实验结果表明:DDQ与CPFX的荷移反应需在丙酮-甲醇(1:4)介质中进行。两者于40℃水浴中恒温30min即可形成1:1络合物,其荧光发射较CPFX有显著的增强。在0.107.2mg/L浓度范围内,荧光强度与质量浓度呈良好线性关系;其检出限为0.1mg/L。本方法用于片剂中环丙沙星的含量测定,其回收率为96.6%-100.2%;标准偏差为1.3%-2.6%。 相似文献
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以含氰基及环丙烷的酰胺类杀菌剂为先导,设计合成了结构全新的双氰基环丙烷甲酰胺类化合物.通过Strecker反应获得中间体2-氨基-2-(取代)苯基乙(丙)腈(1a~1n),以氰乙酸乙酯和1,2-二溴乙烷环经环化、水解得到1-氰基环丙烷-1-甲酸(3),由化合物3和1经缩合反应得到目标化合物4a~4n,其结构均经NMR和HRMS表征.生物活性测试结果表明,在离体条件下,50μg/m L的化合物4f对瓜果腐霉和稻瘟菌的抑制活性分别为55.3%和67.1%;盆栽实验中,400μg/m L的化合物4f对黄瓜霜霉病和小麦白粉病的抑制活性分别为50%和85%,化合物4m对玉米锈病的抑制活性达100%;5μg/m L的化合物4c,4d,4g,4j和4m对蚊幼虫的致死率均60%,600μg/m L的化合物4h和4j对粘虫的致死率分别为66.7%和50%. 相似文献
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弹性力学Hamilton正则方程和Hamilton混合元的等效刚度系数矩阵,均具有直观的辛特性.基于H R变分原理和弹性力学保辛理论建立的对偶变量块体混合元,其等效刚度系数矩阵同样具有直观的辛特性.根据对偶变量块体混合元列式,可直接建立问题的控制方程,进行混合法求解.同时,通过对偶变量块体混合元列式可以导出对偶变量块体位移元列式,建立问题的控制方程后,可先求位移的解.数值实例表明:线性8结点对偶变量块体位移减缩积分元的各力学量的收敛速度均衡、收敛过程稳定、结果精度高,其应力变量的收敛速度与传统的20结点位移协调减缩积分元接近.对偶变量块体位移元具有普适性. 相似文献
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