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991.
992.
无透镜傅里叶变换数字全息波前重建主要采用全息图的一次快速傅里叶变换方法,重建图像不能充分占有重建平面.本文基于像平面滤波技术,提出对物体局部区域光波场进行放大重建并让重建图像布满重建平面的方法,给出具有精细结构物体的数字全息波前重建实例.此外,将数字全息光波场重建视为具有方形出射光瞳的光学系统的相干光成像过程,导出了物体放大图像的分辨率与光学系统相关参量的关系,并通过实验给予证明. 相似文献
993.
Long Huang Feng He Hai Huang Min Yao 《International Journal of Theoretical Physics》2014,53(6):1947-1952
Gravitation deflects light, which has been confirmed by a large number of observation data. f(R)-gravity is modification of Einstein’s gravity. According to the field equations obtained by the action of the f(R) form, a similar Schwarzschild metric is obtained. According to the condition that four-dimension momenta of the photon return to zero and conservation of covariant momenta, we obtain an equation of photon motion in a specific form of f(R)-gravity. We solve the equation to get gravitational deflection angle of light that grazes surface of sun and the calculation result is consistent with the experimental observation data. 相似文献
994.
In laboratory environment, the channel apparatus will generate particular dominant quantum noise. The noise then will give rise to some errors during synchronization. In this work, the accuracies of one qubit transport protocol and entangled states transport protocol in the presence of noise have been studied. With the help of three important and familiar noise models, the quantum noise will degrade the accuracy has been proved. Due to the influence of quantum noise, the accuracy of entangled qubits decrease faster than that of one qubit. The entangled states will improve the accuracy in noise-free channel, and will degrade the accuracy in noise channel. 相似文献
995.
分析了Γ分布密度函数的性质,指出了该密度函数与相应参数之间的关系.主要研究第二个参数对密度的影响,证明了β增大时Γ(α,β)分布密度极大值也增大,还指出了β变化时Γ(α,β)分布密度与另一特定密度曲线交点的变化规律. 相似文献
996.
997.
In this paper, we study polynomials orthogonal with respect to a Pollaczek–Jacobi type weight The uniform asymptotic expansions for the monic orthogonal polynomials on the interval (0,1) and outside this interval are obtained. Moreover, near , the uniform asymptotic expansion involves Airy function as , and Bessel function of order α as in the neighborhood of , the uniform asymptotic expansion is associated with Bessel function of order β as . The recurrence coefficients and leading coefficient of the orthogonal polynomials are expressed in terms of a particular Painlevé III transcendent. We also obtain the limit of the kernel in the bulk of the spectrum. The double scaled logarithmic derivative of the Hankel determinant satisfies a σ‐form Painlevé III equation. The asymptotic analysis is based on the Deift and Zhou's steepest descent method. 相似文献
998.
原子吸收光谱法测定中成药中微量元素 总被引:16,自引:2,他引:16
利用原子吸收光谱法测定了老年咳喘片、复方半夏片、胃痛宁片、拳参片、参芪降糖胶囊、夏桑菊颗粒和美国洋参含片7种中成药中Ca,Mg,Fe,Zn,K,Na,Mn,Cu,Cr,Co,Sr,Ni,Cd和Pb元素的含量。详细研究了消化液(混酸)种类、混酸中HNO3和HClO4比例、消化液体积及消化时间对测定结果的影响。结果表明:所选7种药物中Ca,Mg,Fe,K和Na的含量普遍比较丰富;治疗糖尿病的药物参芪降糖胶囊中Mn的含量较为丰富,而胃痛宁片中有较丰富的Sr,Mn和Cu元素。 相似文献
999.
PENG Yan-Ze 《理论物理通讯》2005,43(2):205-207
New exact solutions in terms of the Jacobi
elliptic functions are obtained to the (2+1)-dimensional breaking
soliton equation by means of the modified mapping method. Limit
cases are studied, and new solitary wave solutions and triangular
periodic wave solutions are obtained. 相似文献
1000.
The multidimensional piston problem is a special initial-boundary value problem. The boundary conditions are given in two conical surfaces: one is the boundary of the piston, and the other is the shock whose location is to be determined later. In this paper, we are concerned with spherically symmetric piston problem for the relativistic Euler equations. A local shock front solution with the state equation p = a 2 ρ, a is a constant and has been established by the Newton iteration. To overcome the difficulty caused by the free boundary, we introduce a coordinate transformation to fix it and employ the linear iteration scheme to establish a sequence of approximate solutions to the auxiliary problems by iteration. In each step, the value of the solution of the previous problem is taken as the data to determine the solution of the next problem. We obtain the existence of the original problem by establishing the convergence of these sequences. Meanwhile, we establish the convergence of the local solution as c → ∞ to the corresponding solution of the classical non-relativistic Euler equations. 相似文献