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971.
使用Monte-Carlo模拟计算了垒下16O+232Th系统转移裂变和复合核裂变碎片角分布及角关联.转移过程、熔合过程和裂变过程分别用半经典模型、耦合道模型及鞍点过渡态统计模型进行模拟.考虑了各物理量分布产生的运动学效应及裂前中子发射和裂后碎片粒子蒸发对碎片角分布及角关联的影响.模拟结果和实验测量的分布相一致.使用折叠角技术借助Monte-Carlo模拟区分转移裂变和复合核裂变是可能的.考虑了转移裂变和裂前中子发射的影响,复合核裂变碎片角分布各向异性异常仍然存在. 相似文献
972.
973.
HUANG Hongbina) b) XING Linglingc) SONG Jiliangd) 《Chinese Journal of Lasers》1997,6(3):213-222
MultipleEfectiveTwo┐photonCorelated┐emisionOpticalBistabilitywithInjectedSquezedVacuumHUANGHongbina),b)XINGLinglingc)SONGJil... 相似文献
974.
A. S. Hamid 《Central European Journal of Physics》2003,1(4):655-668
The three dimensional electron density in momentum space ρ(p) and in wave vector space n(k) was reconstructed for cadmium (Cd). The measurements were performed using the two dimensional angular correlation of annihilation
radiation (2D-ACAR) technique. Enhanced contributions in the spectra were observed around 5.5 mrad, discussed in terms of
a Kahana-like enhancement effect. From another viewpoint, Fermi radii were analyzed in the (λM K), (ALM) and (AHK) planes, and they showed a maximum deviation of about 4% from the free electron Fermi radius. Moreover, comparisons to a
radio-frequency size effect (RFSE) experiment and theoretical band structure calculations (using augmented plane wave (APW),
linear combination of atomic orbital (LCAO) and linear muffin tin orbital (LMTO) methods) were examined. The results showed
a qualitative agreement with both APW and LCAO calculations. However, a favorable agreement with the APW method was determined
via Fermi surface dimensions. The differences of bands' occupation of n(k) between the current work and the APW method were
argued in view of positron wave function in Cd. 相似文献
975.
In many nonlinear optical problems, for example in down-conversion and four-wave mixing, the photons are generated in pairs.
The strong correlation between the photons in a pair, characterized by either the correlations between operators corresponding
to observables associated with individual photons, or the correlated state describing the two photons, may lead to various
nonclassicalities. We discuss some of these nonclassical effects and their experimental demonstrations in nonlinear optical
processes 相似文献
976.
The paper is concerned with the continuous squeezing flow of Oldroyd-type fluids in a two-dimensional wedge. The flow mimics the lubrication action in a squeezing flow and is important in that there exists a similarity solution for any simple fluid. We are only concerned with Oldroyd-type fluids, however. It is shown by using a parameter continuation method that the Oldroyd-B model has a limiting Weissenberg number. The Phan Thien/Tanner model does not have this limiting Weissenberg number. 相似文献
977.
S S Kapoor 《Pramana》1989,33(1):13-20
This article gives an overview of the physics of the fission phenomenon. It provides a brief introduction to the various aspects
of the fission process such as liquid drop model fission barriers, different stages of the fission process, fragment kinetic
energy and mass distributions, nuclear shell effects on fission barriers, fragment angular distributions and rare fission
modes. 相似文献
978.
V. Ch. Venkaiah 《Proceedings Mathematical Sciences》1996,106(1):69-77
Understanding Karmarkar’s algorithm is both desirable and necessary for its efficient implementation, for further improvement
and for carrying out complexity analysis. In this report an algorithm based on the concept of angular projection matrix, to
solve linear programming problems is derived. Surprisingly, this algorithm coincides with the affine version of Karmarkar’s
algorithm. 相似文献
979.
57MeV/u 64Zn+27Al反应中集体流的研究 总被引:1,自引:0,他引:1
贺智勇 J.Peter J.C.Angelique G.Bizard R.Brou D.Cussol A.Kerambrun J.P.Patry R.Regimbart J.C.Steckmeyerr B.Tamain E.Vient G.Auger C.Cabot 《中国物理 C》1994,18(9):800-806
报道了利用4π带电粒子阵列测量的57MeV/u的64Zn轰击27Al反应中的集体物质流.各事件的碰撞参数分类采用平均平行速度方法,反应平面的确定采用横向动量分析方法.实验观察到在反应平面内的集体横向动量(边流参数)随着碰撞参数和粒子产物而变化. 相似文献
980.
The turbulent momentum transport phenomena in a two-dimensional mixing layer are investigated numerically by a discrete vortex method. The numerical model and calculations are verified through a comparison with existing numerical simulations and experimental measurements. The main emphasis is placed on the exploration of the detailed time-dependent instantaneous local momentum fluctuations and on the comparison of numerical results with available experimental measurements. The current simulations confirm qualitatively the various trends in the turbulent momentum flux and fluctuating components of the velocity in the mixing layer found with several experimental results. The study shows that similarity exists in turbulent momentum quantities along the axial direction of the mixing layer. The calculations also show a definite correlation between the passage of a large-scale structure and a burst in the turbulent momentum flux. The probability density functions of the fluctuating quantities are shown to be mostly Gaussian-like, with only a few exceptions. 相似文献