气体放电击穿过程的物理和数值研究

本文对低气压（１０＾－２Ｐａ）热阴极气体放电的击穿过程给出了物理描述和相应的双流体数学型，并发展了一种选择和调整未知初始条件的有效算法，可以通过伴随试射法得到对初始条件十分敏感的非线性两点边值常微分方程组的数值解，从而给出这类气体放电中击穿过程的定量描述。     

一个基于运输规模经济的库存选址模型

介绍了一种新的配送中心(DC)选址模型,在该模型中考虑了一般库存和安全库存成本,同时把从供应商到DC的运输成本也结合进去综合考虑,运输成本是由固定成本加可变成本两部分组成,反映了运输规模经济.     

A comparative study of the silent discharge treatment of saturated and unsaturated hydrocarbon polymers

Dielectric barrier air discharge treatment of polyethylene, polypropylene, polyisobutylene, polystyrene, and polyisoprene substrates has been characterized by x-ray photoelectron spectroscopy (XPS). The relative reactivities of these polymers towards silent discharge oxidation are rationalized in terms of ozone molecules interacting with an excited surface. © 1994 John Wiley & Sons, Inc.     

FexNi100−x nanometric films deposited by laser ablation on SiO2/Si substrates

Fe_xNi_100−x nanometric films were deposited on SiO₂/Si substrates at room temperature using the pulsed laser deposition technique. The targets were Fe-Ni amorphous magnetic foils with composition Fe₅₀Ni₅₀, Fe₃₅Ni₆₅ and Fe₂₂Ni₇₈. Morphological and structural properties of the deposited films were investigated using scanning electron microscopy, Rutherford backscattering spectrometry, grazing incidence X-ray diffraction, and X-ray reflectivity. Electrical and magnetic characteristics of the films were investigated by using the four-point probe and the magneto-optic Kerr effect techniques, respectively. The film properties are strictly dependent on the Fe-Ni compositional ratio.     

Motion Control by ZV Shaper Synthesis Extended for Fractional Systems and Its Application to CRONE Control

Shaping command input or preshaping is used for reducing system oscillation in motion control. Desired systems inputs are altered so that the system finishes the requested move without residual oscillation. This technique, developed by N.C. Singer and W.P. Seering, is used for example in the aerospace field, in particular in flexible structure control. This paper presents the study of ZV shaper for explicit fractional derivative systems (generalized derivative systems). A robustness study of ZV shaper is then presented and applied to improve second generation CRONE control response time. Results from simulation and from a DC motor bench are also given.     

Luminescence properties of α-Al2O3 dosimetric crystals exposed to a high-current electron beam

The spectra of pulsed cathodoluminescence (PCL) and thermoluminescence (TL) in TLD-500 detectors, which were exposed to a strong beam from a pulsed electron accelerator, have been studied. Additional bands in the PCL spectrum and new peaks in the TL curves, which are due to impurity ions, have been revealed. Luminescence bands of F- and F⁺-centers cannot be used in the dosimetry of strong electron beams using TLD-500 detectors because of the saturation of dose dependence and the decrease in the TL yield. It is shown that high doses from these beams can be measured by recording TL in the luminescence band of impurity titanium ions.     

A DC excited waveguide multibeam CO2 laser using high frequency pre-ionization technique

High power industrial multibeam CO₂ lasers consist of a large number of closely packed parallel glass discharge tubes sharing a common plane parallel resonator. Every discharge tube forms an independent resonator. When discharge tubes of smaller diameter are used and the Fresnel numberN ≪ 1 for all resonators, they operate in waveguide mode. Waveguide modes have excellent discrimination of higher order modes. A DC excited waveguide multibeam CO₂ laser is reported having six glass discharge tubes. Simultaneous excitation of DC discharge in all sections is achieved by producing pre-ionization using an auxiliary high frequency pulsed discharge along with its other advantages. Maximum 170 W output power is obtained with all beams operating in EH₁₁ waveguide mode. The specific power of 28 W/m is much higher as compared to similar AC excited waveguide multibeam CO₂ lasers. Theoretical analysis shows that all resonators of this laser will support only EH₁₁ mode. This laser is successfully used for woodcutting     

毛细管放电X光激光中的预脉冲研究

 为研究毛细管放电X光激光中预脉冲放电对增益的影响，用简化的XDCH程序，模拟计算了聚乙烯毛细管充Ar气、2μs脉宽的预脉冲放电过程，把预放电之后的等离子体温度、密度和电离度作为初始条件，输入XDCH程序，进行40kA典型主脉冲放电的计算模拟，给出了一些典型预放电幅度下的增益和电子密度分布情况。比较分析的结果发现，对2μs脉宽的预脉冲，100A的电流将得到较好的增益，并且预言激光线时间谱可能出现双峰结构，空间谱会出现环状结构。     

轴线起爆式螺线管型爆磁压缩发生器理论模型

 对轴线起爆式螺线管型爆磁压缩发生器进行了理论模型研究，建立了爆炸管的一维爆轰驱动模型、螺线管内空间磁场强度分布模型、爆炸管外表面磁压力模型和发生器系统的等效电路模型等，对此类发生器的物理过程进行系统描述。在此基础上，编制了相应的零维数值模拟程序CEMG 1.0，利用该程序分别对四种不同模型参数的发生器进行了理论计算和参数优化，并对其中一模型发生器爆炸管外表面的磁压力及其引起的剩余电感进行了计算，给出了剩余电感与初始输入条件及负载电感的关系，从而得到该模型的输出性能极限。对理论模型的正确性进行了实例验算证明。     

离焦散斑技术研究Kirchhoff板在动载作用期的弯曲

本文使用动态离焦散斑技术,测试板的动态弯曲获得成功。并推导了Kirchhoff板动态变形的有关分析,提出了由最大斜率确定材料常数的思想。显然,这是同离焦散斑方法所测数据直接相关的处理手法。