微束等离子焊接

简要介绍了微束等离子焊接的工艺设备。通过对乌克兰巴顿焊接研究所几个实例的介绍，较全面地阐述了微束等离子焊接工艺方案、焊接设备的各项技术要求和特性。与氩弧焊、激光焊进行了比较，认为微束等离子焊接具有电弧收缩、能量集中、适用于薄壁件焊接的特点，在我国具有广阔的应用前景。     

脉冲等离子体推力器研究综述

简要介绍了脉冲等离子体推力器(PPT)的基本工作原理;回顾了国内外脉冲等离子推力器的发展历史;阐述了它的优势与面临的挑战;分析了需要研究的关键技术与发展方向。     

The local bubble

Recently, observations with the rosat PSPC instrument and the spectrometers onboard the euve satellite have given new detailed information on the structure and physical conditions of the Local Bubble. From the early rocket experiments, and in particular from the WISCONSIN Survey, the existence of a diffuse hot gas in the vicinity of the solar system, extending out to about 100 pc, has been inferred in order to explain the emission below 0.3 keV. The higher angular resolution and sensitivity of rosat made it possible to use diffuse neutral clouds as targets for shadowing the soft X-ray background. Thus, in some directions, more than half of the flux in the 0.25 keV band appears to come from outside the Local Bubble. Further, measurements of the diffuse EUV in the LISM, show surprisingly few emission lines. These findings are in conflict with the standard LHB model, which assumes a local hot (T 10⁶ K) plasma in CIE. Model calculations, based on the non-equilibrium cooling of an expanding plasma, show a promising way of reconciling all available observations. Thus the present temperature within the LB may be as low as 4 × 10⁴ K and its number density as large as 2 × 10^–2 cm ^–3, giving a total pressure that is roughly in agreement with the Local Cloud.Abbreviations CIE collisional ionization equilibrium - ISM Interstellar Medium - LHB Local Hot Bubble - LB Local Bubble - LISM Local ISM - SB superbubble - SXR soft X-ray - SXRB SXR Background - VLISM Very Local ISM Heisenberg Fellow     

瞬态空气等离子体场的全息术研究

采用双波长双脉冲激光全息术,对有激波存在下的空气放电现象进行了研究。建立了双波长电弧折射率场方程,推导出冲击波区的压强同折射率之间的关系式,得出电弧场的压强分布.曲线及等离子体区的温度分布和电子、离子、原子、分子等粒子的数密度分布。     

ISEE卫星等离子体能谱图片处理与初步分析

本文利用图象分析的方法，将ＩＳＥＥ卫星的等离子体能谱图数值化，以便定量地分析ＩＳＥＥ卫星观测到的磁尾等离子体和磁场资料。以及研究磁尾中性片的纤维结构，对今后研究近地磁尾（２２个地球半径以内）各种空间动力学机制，电流结构体系等问题都有很重要的利用价值。     

地面实验室模拟空间等离子体环境的初步测试

空间等离子体和航天器的相互作用对航天器的安全有重要影响，利用空间实验来研究这些作用的代价很大，可以通过在地面实验室中模拟空间等离子体环境来低成本地研究这些相互作用。本研究通过使用ECR等离子体源期望在地面实验室来近似模拟空间等离子体环境。通过初步测量，我们得到了一个比较均匀的等离子体环境。     

空间尘埃的充电过程及与等离子体参数的关系

考虑了地球附近的彗星、行星环、行星际介质等空间尘埃等离子体环境中尘埃颗粒的充电问题．应用典型的空间尘埃等离子体参数，计算了不同种类的尘埃颗粒，以及不同等离子体成分下等离子体中尘粒的平衡电势，得到了尘埃颗粒的平衡电势与尘埃等离子体成分、温度，及其他等离子体参数之间的相互关系．     

Numerical study of magnetic reconnection possibly occurring near heliospheric current sheet

The third-order accurate upwind compact difference scheme has been applied for the numerical study of the magnetic reconnection driven by a plasma blob impacting the heliospheric current sheet, under the framework of the two-dimensional compressible magnetohydrodynamics. The results show that the driven reconnection near the current sheet could occur in about 10–30 min for the interplanetary high magnetic Reynolds number, R_M = 2000–10,000, a stable magnetic reconnection structure can be formed in hour order of magnitude, and there appear some basic properties such as the multiple X-line reconnections, vortex structures, filament current systems, splitting and collapse of the high-density plasma blob. These results are helpful in understanding and identifying the magnetic reconnection phenomena possibly occurring near the heliospheric current sheets.     

壁稳电弧等离子体温度和辐射标准设备的研制

研制了氩壁稳电弧等离子体装置,其最大功率25kW,电流0～140A,4小时内电流的稳定性0.005%,纹波系数0.1%。在可靠的状态诊断实验基础上测试了主要性能。当压力为0.1～0.5MPa、电流不小于20A 时,电弧轴心区等离子体是LTE(局部热力学平衡)的。60A 电流下4小时内 ArI430.0nm 谱线辐射的稳定性±1.0%,1个月内的再现性±1.8%,温度可调范围10000～16000K,不确定度0.4%。同时测定了某些特定谱线斯塔克宽度与电子密度的实验关系。结果表明,性能完全达到了建立10000～15000K温度和近紫外高强度及真空紫外辐射标准的要求。     

“Oblique” Bernstein modes in solar preflare plasma: Generation of second harmonics

Process of second harmonics generation due to development of corresponding instability has been investigated for pure electron weakly oblique Bernstein mode. This mode was supposed to be modified by taking into account the influence of pair Coulomb collisions and weak large-scale electric field in flare loop. Investigated area was located near the loop foot-point in the “lower–middle” chromosphere of active region. It has been shown, that for the Fontenla–Avrett–Loeser model of solar atmosphere the investigated process of second harmonics generation starts at the extremely low threshold values of subdreicer electric field, well before the beginning of “preheating” phase of flare process.