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排序方式: 共有120条查询结果,搜索用时 31 毫秒
81.
Abdulla Albastaki Mohammed Naji Reem Lootah Reem Almheiri Hanan Almulla Afra Alreyami Iman Almarri Zailiang Yu Yueke Zhang Chang Shu Rashed Alghafri 《Electrophoresis》2022,43(18-19):1911-1919
This article details the development of a single multiplex system amplifying 26 rapidly mutating Y-STR markers. A sequenced allelic ladder, constructed for calling alleles of all loci, is introduced. The multiplex system shows the ability to address the limitations of Y-STRs commercial kits in differentiating closely related males. The multiplex performed well in the prevalidation tests and showed great potential to be used in forensic casework. 相似文献
82.
In the present paper, we investigate the asymptotic behavior of the solution of a variational inequality with one-sided constraints on ?-periodically located subsets G ε belonging to the boundary ?Ω of the domain Ω ? ?3. We construct a limit (homogenized) problem and prove the strong (in H 1(Ω)) convergence of the solutions of the original inequality to the solution the limit nonlinear boundary-value problem as ? → 0 in the so-called critical case. 相似文献
83.
A. S. Lyapin 《Mathematical Notes》2007,82(3-4):347-351
We consider a nonlinear nonautonomous hyperbolic equation with dissipation and with a small parameter multiplying the highest derivative with respect to time. This equation also involves a rapidly oscillating external force. Using a standard technique for constructing the trajectory attractor, we can prove the convergence of the attractor of a nonlinear nonautonomous hyperbolic equation with dissipation to the attractor of the corresponding parabolic equation. 相似文献
84.
本文对有向和无向de Bruijn图上的随机游动进行了研究,得出了有向de Bruijn图上简单随机游动任意两点之间平均击中时间的显式表达式,并证明了有向和无向de Bruijn图上随机游动的快速收敛性。 相似文献
85.
86.
This paper proposes a numerical technique that in essence is based upon the classical staggered grids and implicit numerical integration schemes, but that can be applied to problems that include rapidly varied flows as well. Rapidly varied flows occur, for instance, in hydraulic jumps and bores. Inundation of dry land implies sudden flow transitions due to obstacles such as road banks. Near such transitions the grid resolution is often low compared to the gradients of the bathymetry. In combination with the local invalidity of the hydrostatic pressure assumption, conservation properties become crucial. The scheme described here, combines the efficiency of staggered grids with conservation properties so as to ensure accurate results for rapidly varied flows, as well as in expansions as in contractions. In flow expansions, a numerical approximation is applied that is consistent with the momentum principle. In flow contractions, a numerical approximation is applied that is consistent with the Bernoulli equation. Both approximations are consistent with the shallow water equations, so under sufficiently smooth conditions they converge to the same solution. The resulting method is very efficient for the simulation of large‐scale inundations. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
87.
采用快淬法制备稀土镁基贮氢合金。研究了覆盖剂,以及镁含量、热处理工艺对合金电性能的影响。当镁含量为1.09wt%时,0.2C放电容量〉380mAh/g,以2C充放,循环寿命〉500次。经XRD分析,贮氢合金具有纳米晶结构,平均晶粒尺寸〈50nm。PCTN试结果表明,随着温度升高,合金的平台压力增加,平台区域变宽,且平坦。 相似文献
88.
Shifeng Du Dongxiang Zhang Yuxian Shi Qinan Li Baohua Feng Jing-yuan Zhang 《Optics Communications》2008,281(19):5014-5018
We report the characteristics of the amplified stimulated Raman scattering (SRS) pulses generated in liquid benzene by a picosecond (ps) β-barium borate (BBO) optical parametric amplifier (OPA). When the OPA system was used as an energy amplifier for SRS pulses, with a pump energy of 2.4 mJ at 355 nm for the OPA, the maximum output energy of the amplified SRS was about 0.73 mJ for the signal and 0.18 mJ for the idler, the energy conversion efficiency was 30.4% from the pump beam to the amplified third order Stokes component at 635.1 nm. The total efficiency would be as high as 37.9% if the output of the idler is also included. The corresponding spectral line width of the amplified Raman pulse was 11.8 cm−1 with a pulse width of 10.9 ps and a peak power of 67 MW. The OPA system was also used as an amplifier for very weak Raman signal, the slope gain factor of this amplifier was found to be as high as 4.1 × 107 and the energy detection limit was as low as 14.8 aJ per pulse, or 48 photons at 635.1 nm, in particular. Such a detection limit corresponds to approximately 0.5 photons per pulse if the time-gate of the OPA is reduced to 150 fs and it is about the same as or even better than a recently report on the 0.75 photons detection limit for a 150-fs OPA of coherent signal at 800 nm. 相似文献
89.
Andreas Weiermann 《Proceedings of the American Mathematical Society》2004,132(2):553-561
Let be a number-theoretic function. A finite set of natural numbers is called -large if . Let be the Paris Harrington statement where we replace the largeness condition by a corresponding -largeness condition. We classify those functions for which the statement is independent of first order (Peano) arithmetic . If is a fixed iteration of the binary length function, then is independent. On the other hand is provable in . More precisely let where denotes the -times iterated binary length of and denotes the inverse function of the -th member of the Hardy hierarchy. Then is independent of (for ) iff .
90.