Proton Elastic Scattering from ^14Be and Halo Effects

The elastic scattering of p-^14Be system at Elab = 200 MeV is evaluated within the relativistic impulse approximation. We discuss the effects of the halo neutrons on the three observables of the elastic scattering system, such as differential cross section dσ/ dΩ, analyzing power Ay and spin rotation Q. The results of the three observables of the elastic scattering of p-^14Be system are compared with those of p-^12C and p-^16O systems at the same energy as E1ab = 200 MeV. We have found that in the small angular region the Ay and Q, as well as dσ/dΩ, are quite sensitive to the nucleon density distributions on the surface of the target nucleus and offer some unique behaviors of halo nuclei.     

公交车调度的模型

建模思想注重理论联系实际 .从求各时间段的最大断面客容量出发 ,考虑到满载率不应超过1 2 0 %及其它实际需求 ,求出了最小车辆数和一个可行的最优发车时刻表 .     

Variation of Ionization Mechanisms with q in the Collision of He^2＋ with C^q＋

The ionization process in the collisions of He^2＋ with C^q＋ （q = 0-5） is investigated by using the continuum-distorted-wave eikonal-initial-state approximation. Double-differential cross sections for 1s and 2s sub-shells are obtained at the electron-ejected angle θ = 0° with the projectile energy ranging from 30keV/u to 10MeV/u. Variation of ionization mechanisms with q in C^q＋ is studied, and the dependences on the projectile energies and target sub-shells are also discussed. It is found that in the whole energy range, the absolute values of soft collision （SC） and binary encounter （BE） peaks decrease with increasing q. For the lower incident energies, the electron capture to the projectile continuum （ECC） peak decrease with increasing q as well as SC and BE peaks. For the higher incident energies （〉 1 MeV/u）, the absolute value of ECC peak increases with increasing q, so that the crossings of cross sections appear for C^q＋ with different q. This can be explained by the matching of velocities between the projectile and the electron initially bound to the target.     

具有Clifford断面的纯正半群

本文研究有Clifford断面的纯正半群.为了获得主要的结构定理，证明了纯正半群有群断面当且仅当它是矩形群;利用半格和矩形带，建立了有Clifford断面的纯正半群的结构.     

同余自由的具有Q-逆断面的正则半群

本文讨论具有逆断面的正则半群的同余格对于它本身结构的影响．　我们给出了这类半群有最简单的同余格，即只有平凡同余的充分必要条件．     

GGC-401A型河床断面测绘仪通过验收

由航天部二五所与船舶总公司第七研究院第七二六所共同开发研制的“GGC-401A型河床断面测绘仪”,于5月16日—20日,在七二六所的浙江莫干山对河口水库试验站水域,进行了水上动态验收试验。来自航天部、船舶总公司等有关单位的领导和工程技术人员30多人参加验收试验,一致通过验收。 GGC-401A型河床断面测绘仪由水声回波测深、雷达测距、计算机实时信号处理绘图打字输出等部分组成。它随着水陆两用车的航迹,能实时精确地测量     

利用侧扫声呐观察和测量河床推移质的运动

利用侧扫声呐技术，观测推移质输沙的形式之一即沙波的输沙现象，可以同时确定推移质的输移量和观察其运动过程，是一种研究推移质运动的经济而有效的新方法．     

超声测断面形状误差分析及测试方法探讨

本文对超声波斜入射情况下存在的测距误差进行了分析，给出了数学修正的公式，并通过实验进行了验证，对测量不同形状空间的测试方法了探讨。本文的讨论对提高测试精度和选择工程测试方案有参考意义。     

金属材料的超声迟延合成断面成像

本文叙述了笔者利用“迟延合成信号处理方法”制做金属材料断面声学图像的方法、实验装置和初步实验结果。实验结果表明,对于检测人工加工的圆孔形缺陷的分布和定位是准确可靠的,经过进一步的研究,有可能为超声断面成像探伤技术提供一种新方法。