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151.
作为在轨管理的关键部分,良好的充电控制是保证蓄电池长寿命的重要因素.对于氢镍蓄电池,压力-容量充电控制是最理想的充电控制方式,但存在压力检测难度大、控制策略复杂等困难.天宫一号目标飞行器氢镍蓄电池通过大量的压力测量地面可靠性试验,解决了压力传感器的测量稳定性及一致性问题;同时提出柔性充电控制策略,给出了压力-容量标准曲线、不同荷电态下的充电电流及压力控制点修正系数.在轨数据表明,天宫一号目标飞行器氢镍蓄电池压力-容量充电控制稳定,满足设计要求.  相似文献   
152.
The review is aimed at the discussion of recent results on spectral profiles produced in collisions of few-electron atoms/ions. Calculations of spectral profiles produced by atom/ion collisions need some preliminary quantum-chemical information such as potential energy surfaces, dipole transition moments, etc. The main advantage of few-electron systems is that all input data can be obtained ab initio or analytically, thus the profiles calculated do not include any fit parameters. Two specific examples have been discussed. The first one deals with radiative transitions accompanying charge-exchange in collisions of one-electron ions with bare nuclei. The second example concerns radiative transitions produced by H + H collisions.  相似文献   
153.
基于串联型顺序开关分流调节器(S4R)功率调节技术,针对卫星一次电源可能出现的所有故障,建立了仿真平台.该平台的建立克服了现有仿真平台无法仿真故障的不足,是辅助电源设计、故障复现及可靠性测试的有力手段.首先,参考大量文献数据,对故障类别进行分析汇总;然后,在Matlab/Simulink下搭建卫星电源故障仿真平台,并利用MatlabGUI作为操作界面;最后进行仿真验证,结果表明该平台可根据故障发生部位及注入量的大小正确反映出故障输出结果.  相似文献   
154.
采用电子、质子、氦核和另外一种微量离子代替氧离子的4组元模型分别计算了Fe^11 ,Mg^9 ,Mg^7 ,Ne^7 和Si^7 等微量离子的漂移速度和温度,并和SUMER的观测结果进行了比较。  相似文献   
155.
航空电瓶内阻测量与剩余容量探讨   总被引:2,自引:0,他引:2  
论述了电瓶内阻的基本测量方法。利用3550电瓶内阻测试仪对典型的航空电瓶进行实际测量,结果表明,对于酸性电瓶判断比较正确,而对碱性电瓶判断不正确。  相似文献   
156.
The combination of recent observational and theoretical work has completed the catalog of the sources of heliospheric Pickup Ions (PUIs). These PUIs are the seed population for Anomalous Cosmic Rays (ACRs), which are accelerated to high energies at or beyond the Termination Shock (TS). For elements with high First Ionization Potentials (high-FIP atoms: e.g., H, He, Ne, etc.), the dominant source of PUIs and ACRs is from neutral atoms that drift into the heliosphere from the Local Interstellar Medium (LISM) and, prior to ionization, are influenced primarily by solar gravitation and radiation pressure (for H). After ionization, these interstellar ions are pickup up by the solar wind, swept out, and are either accelerated near the TS or beyond it. Elements with low first ionization potentials (low-FIP atoms: e.g., C, Si, Mg, Fe, etc.) are also observed as PUIs by Ulysses and as ACRs by Wind and Voyager. But the low-FIP composition of this additional component reveals a very different origin. Low-FIP interstellar atoms are predominantly ionized in the LISM and therefore excluded from the heliosphere by the solar wind. Remarkably, a low-FIP component of PUIs was hypothesized by Banks (J. Geophys. Res. 76, 4341, 1971) over twenty years prior to its direct detection by Ulysses/SWICS (Geiss et al., J. Geophys. Res. 100(23), 373, 1995) The leading concept for the generation of Inner Source PUIs involves an effective recycling of solar wind on grains near the Sun, as originally suggested by Banks. Voyager and Wind also observe low-FIP ACRs, and a grain-related source appears likely and necessary. Two concepts have been proposed to explain these low-FIP ACRs: the first concept involves the acceleration of the Inner Source of PUIs, and the second involves a so-called Outer Source of PUIs generated from solar wind interaction with the large population of grains in the Kuiper Belt. We review here the observational and theoretical work over the last decade that shows how solar wind and heliospheric grains interact to produce pickup ions, and, in turn, anomalous cosmic rays. The inner and outer sources of pickup ions and anomalous cosmic rays exemplify dusty plasma interactions that are fundamental throughout the cosmos for the production of energetic particles and the formation of stellar systems.  相似文献   
157.
电动飞机正在国内外通用航空领域蓬勃发展,并影响着未来航空的发展方向。利用电推进技术对无人机进行电动化改造,能大大提高无人机的安全性、可靠性和维修性,降低使用成本。以天翼1无人机为电动化改造对象,提出了电动化改造方案,详细计算分析了电推进系统中电动机和锂电池组的主要参数,并从无人机的重量重心、性能以及电推进系统的安装方式等方面分析了改造的可行性。分析结果表明,天翼1无人机电动化改造基本可行;并提出了后续改造实施中需注意的问题。  相似文献   
158.
Radiation hazard for space missions is mainly due to cosmic ray protons, helium nuclei and light ions, whose energy spectrum is maximum around 1 GeV per nucleon but remains non-negligible for energies up to 15 GeV per nucleon. Nuclear reactions induced by high energy protons are often described by intranuclear cascade plus evaporation models. The attention is focused here on the Liège Intranuclear Cascade model (INCL), which has been shown to reproduce fairly well a great deal of experimental data for nucleon-induced reactions in the 200 MeV to 2 GeV range, when coupled with the ABLA evaporation-fission code. In order to extend the model to other conditions relevant for space radiation, three improvements of INCL are under development. They are reported on here. First, the reaction model has been extended to nucleon–nucleus reactions at incident energies up to 15 GeV, mainly by the inclusion of additional pion production channels in nucleon–nucleon collisions during the cascade. Second, a coalescence mechanism for the emission of light charged particles has been implemented recently. Finally, the model has been modified in order to accommodate light ions as projectiles. First results are shown and compared with illustrative experimental data. Implications for issues concerning radiation protection in space are discussed.  相似文献   
159.
MEO卫星氢镍蓄电池组自主充电管理方法   总被引:1,自引:1,他引:0  
MEO卫星运行轨道存在不可测控弧段,每年有长光照期和两个地影季,为此对星上充电管理的自主能力提出了较高要求。文章介绍了我国首颗在轨飞行的MEO卫星的氢镍蓄电池组的在轨自主管理方法,包括地影季的电压-温度(V-T)控制与电量计结合的充电管理方法和长光照期控制电池压力的涓流管理方法,并给出了在轨飞行的实际效果,可作为后续卫...  相似文献   
160.
Measurements of the anomalous cosmic ray (ACR) isotopic composition have been made in three regions of the magnetosphere accessible from the polar Earth orbit of SAMPEX, including the interplanetary medium at high latitudes and geomagnetically trapped ACRs. At those latitudes where ACRs can penetrate the Earth's magnetic field while fully stripped galactic cosmic rays (GCRs) of similar energies are excluded, a pure ACR sample is observed to have the following composition: 15N/N < 0.023, 18O/16O < 0.0034, and 22Ne/20Ne = 0.077(+0.085, –0.023). We compare our values with those found by previous investigators and with those measured in other samples of solar and galactic material. In particular, a comparison of 22Ne/20Ne measurements from various sources implies that GCRs are not simply an accelerated sample of the local interstellar medium.  相似文献   
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