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991.
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995.
First-principles study on the effect of Hf content onmartensitic transformation temperatureof TiNiHf alloy 总被引:1,自引:0,他引:1
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In this paper a first-principles study of the electronic structure and stability of B2
TiDFT TiNiHf 电子结构 马氏体转化温度 平面波 DFT, TiNiHf, electronic structure, martensitic
transformation temperature Project supported by the National Natural Science Foundation of China
(Grant No 50471018). 3/3/2006 12:00:00 AM 6/7/2006 12:00:00 AM In this paper a first-principles study of the electronic structure and stability of B2 Ti1-xNiHfx (x = 0.2, 0.4, 0.6) and B19′ Ti1-xNiHfx(x = 0, 0.5) alloys is presented. The calculations are performed by the plane-wave pseudopotential method in the framework of the density functional theory with the generalized gradient approximation. This paper calculates the lattice parameters, density of states, charge density, and heats of formation. The results show that the electronic structure and stability of B2 Ti1-xNiHfx change gradually with Hf content. However, Hf content has little effect on the electronic structure and stability of B19′ Ti1-xNiHfx. The mechanism of the effect of Hf content on martensitic transformation temperature of TiNiHf alloys is studied from the electronic structure. 相似文献
996.
The resolution and classical noise in ghost
imaging with a classical thermal light are investigated
theoretically. For ghost imaging with a Gaussian Schell model
source, the dependences of the resolution and noise on the spatial
coherence of the source and the aperture in the imaging system are
discussed and demonstrated by using numerical simulations.
The results show that an incoherent source and a large aperture
will lead to a good image quality and small noise. 相似文献
997.
介绍了微分散射截面测量过程中的气压效应 ,通过深入分析得出了二次散射系数E(θ)与零度角的强度A0 成正比 ,随散射角θ的增加而增加以及它的值可正可负 .通过与实验的对比 ,证实了前两条结论 ,并指出可把该结论用于指导实验. The pressure effect for the measurement of differential cross section is introduced and analysed in detail. Three conclusions are obtained: the double scattered coefficient E(θ) is proportional to the strength A 0 of the excitations measured at 0°; E(θ) increases with the increasing of scattered angle; the values of E(θ) can be positive or negative. The front two conclusions are tested by experiment, and it is pointed that they are helpful to the measurement of differential cross section. 相似文献
998.
概述了为核反应模型计算用的“中国评价核参数库”的发展和结构 ,指出了该数据库在国际核反应数据模型计算的“推荐输入参数库”中的作用和地位 .目前正研制更新的CENPL ,一方面将检验、更新和扩充数据 ,特别注重研究适用于更高能区和非稳定核区的模型参数 ;另一方面发展其检索软件和网络软件 ,实现网络在线服务. The Chinese Evaluated Nuclear Parameter Library (CENPL) for the model calculations of nuclear reactions was developed in the past ten years. The International Atomic Energy Agency has constructed a Reference Input Parameter Library (RIPL) for the calculations of nuclear reaction data in the meantime. All data files of CENPL are adopted as the RIPL Starter Files. The model parameters estimated and recommended by our group are specially selected as recommended files. The updated CENPL is being developed... 相似文献
999.
We propose a scheme for realizing a controlled teleportation of random
$M$-qudit quantum information under the control of $N$ agents. The resource
consumption includes a prearranged $(2M + N + 1)$-qudit entangled quantum
channel and $(2M + N + 1)\log _2 d$-bit classical communication. And the
quantum operations used in the teleportation process are a series of
generalized Bell-state measurements, single-qudit measurements, qudit
$H$-gates, qudit-Pauli gates and qudit phase gates. It is shown that the
original state can be restored by the receiver only on condition that
all the agents work in collaboration with each others.
If one agent does not cooperate with the other, the original
state cannot be fully recovered. 相似文献
1000.
Experimental study on imploding characteristics of wire-array Z pinches on Qiangguang-1 facility 总被引:1,自引:0,他引:1
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To investigate the imploding characteristics of cylindrical wire
array, experiments with load current varying from 1.5\,MA to 1.7\,MA
were carried out on the Qiangguang-1 facility. The complicated
temporal-spatial distribution of x-ray radiation was measured by the
one-dimensional (1D) x-ray imaging system. Other diagnostic
equipments including the x-ray power meter (XRPM) and the
time-integrated pinhole camera were used to record time-resolved
x-ray power pulse and pinhole x-ray images. Analysis shows that the
fast leading edge of the local x-ray radiation pulse is of primary
importance in sharpening x-ray power pulse rather than the temporal
synchrony and the spatial uniformity of implosion. Experimental
results indicated that the better axial imploding synchrony, the
faster the increase of x-ray power for an array consisting of 32
tungsten wires of 5\mum diameter than for the others, and the
higher the x-ray radiation power with maximal convergence ratio
(r_0/r_1) of 10.5. A `zipper-like' effect of x-ray radiation
extending from the anode to the cathode was also observed. 相似文献