广义不确定关系与整体单极黑洞Dirac场的熵

将广义不确定关系引入新的态密度方程，采用WKB近似方法，对含整体单极黑洞Dirac场的熵进行了直接计算，所得黑洞熵与它的视界面积成正比，以此揭示了黑洞熵是其视界面处量子态的熵.与brick-wall模型方法不同，该结果不需要取任何截断.同时表明，用此方法不仅可以计算黑洞标量场的熵，而且可以计算Dirac场的熵.     

氟锆酸盐玻璃光纤的研制

本文介绍聚全氟乙丙烯包皮的氟锆酸盐(ZrF_4-BaF_2-LaF_3-AlF_3-NaF)玻璃光纤的制备方法.研究了各种工艺因素对氟锆酸盐玻璃和光纤散射损耗的影响.结果表明,选择适当的熔化温度和均化时间,玻璃熔化和光纤拉制时环境中低的水含量是制得的损耗氟锆酸盐玻璃光纤的关键;配合料中引入适量NH_4HF_2,选用温度结构合理的拉丝炉及拉丝工艺也有助于降低光纤的损耗.在此工作基础上,获得了波长2.32μm处损耗为0.24dB/m的氟锆酸盐玻璃光纤.     

连续调节反衬度观察位相物体的新方法

在4F系统中,利用光栅可以完成位相振幅转换,能够实现连续调节反衬度,因而观察位相物体的各部分就更清楚。一、引言观察透明的位相物体,必需把位相的信息转换     

In, Al共掺杂ZnO纳米串光电探测器的组装与研究

用化学气相沉积法合成了高密度的In, Al共掺杂ZnO纳米串, 用合成出的纳米串组装成了光电探测器. 纳米串为六角纤锌矿结构, 平均长度大约为5 μ m. 研究了光电导的机制以及光电探测器的光电特性, 包括在暗环境及紫外照射下的伏安特性、光电响应率和光电响应时间. 结果表明, 器件存在内部增益机制, 光响应时间小于0.5 s, 衰减时间约为23 s, 可用于光电探测.     

The multi-dimensional limiters for solving hyperbolic conservation laws on unstructured grids

Novel limiters based on the weighted average procedure are developed for finite volume methods solving multi-dimensional hyperbolic conservation laws on unstructured grids. The development of these limiters is inspired by the biased averaging procedure of Choi and Liu [10]. The remarkable features of the present limiters are the new biased functions and the weighted average procedure, which enable the present limiter to capture strong shock waves and achieve excellent convergence for steady state computations. The mechanism of the developed limiters for eliminating spurious oscillations in the vicinity of discontinuities is revealed by studying the asymptotic behavior of the limiters. Numerical experiments for a variety of test cases are presented to demonstrate the superior performance of the proposed limiters.     

Phase-only hologram generation based on integral imaging and its enhancement in depth resolution

We introduce a phase-only hologram generation method based on an integral imaging,and propose an enhancement method in representable depth interval.The computational integral imaging reconstruction method is modified based on optical flow to obtain depth-slice images for the focused objects only.A phaseonly hologram for multiple plane images is generated using the iterative Fresnel transform algorithm.In addition,a division method in hologram plane is proposed for enhancement in the representable minimum depth interval.     

Determining Nuclear Form factor for Detection of Dark Matter in Relativistic Mean Field Theory

In this work, we derive the nuclear form factor for the spin-independent collision between the WIMPs and nucleus in terms of the relativistic mean field (RMF) theory. Comparison with the traditional form factors which are commonly used in literature is given and it is found that our results are slightly above that of the 2PF model by 4% to 8%, but deviate from the Helm form factor by 15% to 25% for the whole recoil energy spectrum of 0 ∽ 100keV. Moreover, taking Xe and Ge as examples, we show the dependenceof the form factor on the recoil energy.     

Kuramoto model of coupled oscillators with positive and negative coupling parameters: an example of conformist and contrarian oscillators

We consider a generalization of the Kuramoto model in which the oscillators are coupled to the mean field with random signs. Oscillators with positive coupling are "conformists"; they are attracted to the mean field and tend to synchronize with it. Oscillators with negative coupling are "contrarians"; they are repelled by the mean field and prefer a phase diametrically opposed to it. The model is simple and exactly solvable, yet some of its behavior is surprising. Along with the stationary states one might have expected (a desynchronized state, and a partially-synchronized state, with conformists and contrarians locked in antiphase), it also displays a traveling wave, in which the mean field oscillates at a frequency different from the population's mean natural frequency.