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31.
Considering a single-mode laser system with cross-correlated additive colored noise and multiplicative colored noise, we study the effects of correlation among noises on the normalized intensity correlation function C(s).C(s) is derived by means of the projection operator method. 相似文献
32.
The paper discusses the basic design of the critical facility, whose main purpose is the physics validation of AHWR. Apart
from moderator level control, the facility will have shutdown systems based on shutoff rods and multiple ranges of neutron
detection systems. In addition, it will have a flux mapping system based on 25 fission chambers, distributed in the core.
We are planning to use this reactor for experiments with a suitable source to simulate an ADS system. Any desired sub-criticality
can be achieved by adjusting the moderator level. Apart from perfecting our experimental techniques, in simple configurations,
we intend to study the one-way coupled core in this facility. Preliminary calculations, employing a Monte Carlo code TRIPOLI,
are presented.
相似文献
33.
J. Adam K. Katovsky A. Balabekyan V. G. Kalinnikov M. I. Krivopustov H. Kumawat A. A. Solnyshkin V. I. Stegailov S. G. Stetsenko V. M. Tsoupko-Sitnikov W. Westmeier 《Pramana》2007,68(2):201-212
Target-blanket facility ‘Energy + Transmutation’ was irradiated by proton beam extracted from the Nuclotron Accelerator in
Laboratory of High Energies of Joint Institute for Nuclear Research in Dubna, Russia. Neutrons generated by the spallation
reactions of 0.7, 1.0, 1.5 and 2 GeV protons and lead target interact with subcritical uranium blanket. In the neutron field
outside the blanket, radioactive iodine, neptunium, plutonium and americium samples were irradiated and transmutation reaction
yields (residual nuclei production yields) have been determined using γ-spectroscopy. Neutron field's energy distribution
has also been studied using a set of threshold detectors. Results of transmutation studies of 129I, 237Np, 238Pu, 239Pu and 241Am are presented.
相似文献
34.
V. Wagner A. Krása M. Majerle F. Křížek O. Svoboda A. Kugler J. Adam V. M. Tsoupko-Sitnikov M. I. Krivopustov I. V. Zhuk W. Westmeier 《Pramana》2007,68(2):297-306
The set-up ‘energy plus transmutation’, consisting of a thick lead target and a natural uranium blanket, was irradiated by
relativistic proton beams with the energy from 0.7 GeV up to 2 GeV. Neutron field was measured in different places of this
set-up using different activation detectors. The possibilities of using the obtained data for benchmark studies are analyzed
in this paper. Uncertainties of experimental data are shown and discussed. The experimental data are compared with results
of simulation with MCNPX code.
相似文献
35.
The mechanical design of the target module of an accelerator driven subcritical nuclear reactor system (ADSS) calls for an
analysis of the related thermal-hydraulic issues because of large amount of heat deposition in the spallation region during
the course of nuclear interactions with the molten lead bismuth eutectic (LBE) target. The LBE also should carry the entire
heat generated as a consequence of the spallation reaction. The problem of heat removal by the LBE is a challenging thermal-hydraulic
issue. For this, one has to examine the flows of low Prandtl number fluids (LBE) in a complex ADSS geometry. In this study,
the equations governing the laminar flow and thermal energy are solved numerically using the streamline upwind Petrov-Galerkin
(SUPG) finite element (FE) method. The target systems with a straight and a nozzle guide have been considered. The principal
purpose of the analysis is to trace the flow and temperature distribution and thereby to check the suitability of the flow
guide in avoiding the recirculation or stagnation zones in the flow space that may lead to hot spots.
相似文献
36.
Zhihao Geng 《Physics letters. A》2010,375(2):214-219
The doping and temperature dependence of the electronic Raman response in cuprate superconductors is studied within the kinetic energy driven superconducting mechanism. It is shown that the temperature dependent depletion at low-energy shifts is faster in the B1g symmetry than in the B2g symmetry. In analogy to the domelike shape of the doping dependent superconducting transition temperature, the maximal peak energy in the B2g channel occurs around the optimal doping, and then decreases in both underdoped and overdoped regimes. Moreover, the overall density of Cooper pairs increases with increasing doping in the underdoped regime. 相似文献
37.
近年来,多铁异质结中电控磁性研究引起了广泛关注,已成为多铁领域的热点.现代自旋电子学器件(如磁内存)通常利用电流产生的磁场或自旋转移扭矩效应驱动磁反转来实现数据擦写,但这带来高额能耗和热量,成为亟待解决的关键难题.而利用多铁异质结实施电场驱动磁反转则有望大幅降低能耗,从而实现高速、低能耗、高稳定性新型高密度磁存储、逻辑及其他自旋电子学器件.在当前器件发展的微型化趋势下,探索可集成化的微纳尺度电场驱动磁反转方案显得越发重要.本文针对发展新型磁电器件所面临的微型化关键问题,回顾了微纳尺度电场驱动磁反转研究的新进展,主要关注小尺度多铁异质结中电控磁的新特点、新方法及相关物理机理的实验和理论成果,讨论了进入纳米尺度将面临的挑战,并对未来研究工作提出一些展望. 相似文献
38.
39.
通过将2个4,4''-联吡啶基团用偶氮基团连接,我们合成了新的配体顺式-和反式-1,2-二((4,4''-联吡啶)-3-氮烯)(cis-L和trans-L),并利用trans-L与银离子和钴离子构筑了配位聚合物{[Ag2(trans-L)(ClO4)2]·4CH3CN}n(1)和{[Co(trans-L)2(H2O)2](ClO4)2}n(2)。其中1为一维梯形链,链与链之间通过π-π以及Ag…Ag相互作用堆积;2为三维无限dendrimer结构,其Co中心具有合适的氧化还原电位,在以荧光素为光敏剂的条件下,可作为光催化剂实现光解水放氢。 相似文献
40.
It is crucial to deal with the grid non‐orthogonality effectively in solving the flow in complex geometries, especially at high Reynolds numbers. In this study, the newly proposed Coupled and Linked Equations Algorithm Revised‐ER (CLEARER) algorithm is adopted to solve this problem successfully. In CLEARER algorithm the second relaxation factor is introduced in constructing the contravariant interface velocities, by setting it to a low value. CLEARER algorithm can overcome the severe grid non‐orthogonality and non‐linearity of equations effectively. After the numerical results with CLEARER are validated with the benchmark solutions, this algorithm is used to solve the lid‐driven flow in inclined cavity with inclination angles varying from 10 to 170°, and Reynolds numbers varying from 5000 to 15 000. The streamlines and the centerline velocity distributions are provided in detail for all cases, which may offer some guidance for the study in this area. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献