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介绍一种新研制的无溶剂螺压双基推进剂,其比冲为2256N·s/kg,燃速突破了40mm/s,压力指数小于0.5,采用Pb-Cu-Ni-C.B四元催化剂。 相似文献
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I.N. Myagkova M.I. PanasyukL.L. Lazutin E.A. MuravievaL.I. Starostin T.A. IvanovaN.N. Pavlov I.A. RubinshteinN.N. Vedenkin N.A. Vlasova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The Russian microsatellite “Universitetskiy-Tatiana” was launched on Jan. 20, 2005 and was both a scientific and educational mission. Its two main aims were declared as: (1) monitoring of the energetic particles dynamics in the near-Earth space environment after solar events and during quiet times, (2) educational activities based on experimental data obtained from the spacecraft. In this paper observations acquired during Dec. 5–16, 2006, known as “Solar Extreme Events 2006”, were analyzed. The “Universitetskiy-Tatiana” microsatellite orbit permits one to measure both solar energetic particle dynamics, variations of the boundary of solar particle penetration, as well as relativistic and sub-relativistic electrons of the Earth’s outer radiation belt during and after magnetic storms. Both relativistic electrons of the Earth’s outer radiation and solar energetic particles are an important source of radiation damage in near-Earth space. Therefore, the presented experimental results demonstrate the successful application of a small educational spacecraft both for scientific and educational programs. 相似文献
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选取第23太阳活动周(1997—2006年)期间542例由太阳爆发活动驱动的行星际激波事件,分析确定了太阳源头和行星际空间中影响行星际激波能否到达地球轨道的关键物理参数;在此基础上,建立了预测行星际激波能否到达地球的新预报模型(EdEaSPM). 回溯预报结果表明,EdEaSPM模型的预报成功率约为66%,略高于国际一流预报模型的预报成功率;EdEaSPM模型的虚报率未超过50%,改善了当前国际主流模型虚报率较大的情况;对于偏度指标,虽然当前所有模型的偏度值均大于1,但EdEaSPM模型的偏度值最接近于1且明显小于其他模型的偏度值;EdEaSPM模型的其他评价指标也都高于国际主流模型的相应指标. 此外,选取2012年期间的激波事件对EdEaSPM模型进行了预报检验,预测结果与实际情况吻合. EdEaSPM模型不仅能够提前约1~3天进行预报,而且预报效果与国际一流模型具有可比性,尤其是在提高预报成功率及降低虚报率方面具有一定优势. 相似文献
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P. Pappa Kalaivani O. Prakash Li Feng A. Shanmugaraju Liu-Guan Ding Lei Lu Weiqun Gan 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2019,63(10):3390-3403
We have established a data set of 58 major hybrid SEP events associated with meter-to-decahectometer wavelength (m-to-DH) type II bursts, solar flares, and radio-load CMEs during the period of 1997–2014. The main focus of our study is to address the following two questions: Does the interaction of CMEs play a role in the enhancement of SEP intensity? Is there any difference in the seed population, and parent eruptions in the SEP events with and without CME interactions? Hence, the sample of 58 events is classified into two sets: (i) 35 non-interacting-CME-associated SEP events; (ii) 23 interacting-CME-associated SEP events. All the characteristics of SEPs, their associated CMEs/flares and the relationships between them are statistically analyzed and compared. Some of the basic attributes and relative elemental abundances (Fe/O ratios) of the both the sets are also compared. The results indicate that the seed particles in non-interacting-CME-associated SEP events are mostly from solar wind/coronal materials. But in the case of interacting-CME-associated SEP events, it may be associated with both flare material from preceding flares and coronal materials from solar wind/preceding CMEs. The correlation studies reveal that there are clear correlations between logarithmic peak intensity of SEP events and properties of CMEs (space speed: cc?=?0.56) and solar flares (peak intensity: cc?=?0.40; integrated flux: cc?=?0.52) for non-interacting-CME-associated SEP events. But these correlations are absent for the interacting-CME-associated events. In addition, the results suggest that interaction of primary CMEs with their preceding CMEs plays an important role in the enhancement of peak intensity of SEPs at least for a set of m-to-DH type II bursts associated SEP events. 相似文献
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