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排序方式: 共有152条查询结果,搜索用时 15 毫秒
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硅液相外延生长的晶向自动偏离现象 总被引:2,自引:0,他引:2
通过对液相外延的薄膜X衍射测试,结果显示不论衬底是否偏离[111]晶向,外延层在同一衍射位置都出现了双峰。经比较分析,确认了硅(111)面在液相外延生长时存在晶向自动偏转现象。 相似文献
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在国际参考电离层模型和多层准抛物模型的基础上,提出了一种混合应用两种模型进行电离层建模的新方法.利用射线追踪技术,分别对混合模型和传统国际参考电离层模型下短波射线在电离层中的轨迹进行了仿真,得到了电波群路径.通过与实测电波群路径的对比,结果表明:对中国中纬度地区在电离层混合模型下的射线追踪精度优于传统国际参考电离层模型下的射线追踪精度,同时混合建模方法降低了多层准抛物模型对输入条件的要求,扩展了多层准抛物模型在射线追踪技术中的应用范围. 相似文献
54.
The Dark Matter Particle Explorer (DAMPE) mission is one of the five scientific space science missions within the framework of the Strategic Pioneer Program on Space Science of the Chinese Academy of Science (CAS) approved in 2011. The main scientific objective of DAMPE is to detect electrons and photons in the range of 5GeV-10TeV with unprecedented energy resolution (1.5% at 100GeV) in order to identify possible Dark Matter (DM) signatures. It will also measure the flux of nuclei up to above 500TeV with excellent energy resolution (40% at 800GeV), which will bring new insights to the origin and propagation high energy cosmic rays. With its excellent photon detection capability, the DAMPE mission is well placed for new discoveries in high energy-ray astronomy as well. 相似文献
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Jongdae Sohn Suyeon Oh Yu Yi 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The RV-2N-series instruments onboard Luna missions and the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument onboard Lunar Reconnaissance Orbiter (LRO) were designed to characterize the global lunar radiation environment and its biological impacts by measuring cosmic ray (CR) intensity. In this study, we have shown that the RV-2N-series instruments onboard of Russian Luna missions and the CRaTER reliably detect both background CRs and solar proton events (SPEs) in the lunar radiation environment using the proton intensity measured by the RV-2N-series onboard Luna missions out of the Russian Luna program for the exploration of the Moon (November 1970–August 1975) and the CR intensity on the Moon observed by the CRaTER (June 2009–March 2011). Those were compared with the CR intensities observed by neutron monitors (McMurdo, Thule, Oulu) on the Earth. The sunspot number is used as the index of solar activity (NOAA National Geophysical Data Center). As a result, the background CR intensities on the Moon turned out to have a good anti-correlation with the solar activity. We have also identified the proton intensity increasing events on the Moon which have the similar profiles to those observed by neutron monitors on the Earth. Most of these events show the significant increase of proton intensities in the lunar radiation environment when the SPEs associated with solar eruptions are verified. Therefore, most of the proton intensity increasing events are associated with the energetic solar particles in the lunar environment. 相似文献
57.
脉冲星导航试验卫星科学观测数据分析 《空间控制技术与应用》2017,43(2):1-6
脉冲星导航试验卫星是我国发射的一颗专用试验卫星.经过4个多月的在轨观测,该卫星已成功获取了大量观测数据.介绍利用该卫星搭载的掠入射聚焦型X射线探测器在近4个月中对PSR B0531+21获得的观测数据第一批处理结果.本文详细阐述掠入射聚焦型X射线探测器的观测模式,给出脉冲星观测数据的处理方法以及脉冲星参数的拟合过程,利用基于第一手观测数据的脉冲星精化参数验证掠入射聚焦型探测器在轨工作性能,得以回答使用国产X射线探测器是否能够“看得见”脉冲星问题. 相似文献
58.
Solar proton events recorded in the stratosphere during cosmic ray balloon observations in 1957–2008
G.A. Bazilevskaya V.S. MakhmutovY.I. Stozhkov A.K. SvirzhevskayaN.S. Svirzhevsky 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
Long-term balloon observations have been performed by the Lebedev Physical Institute since 1957 up to the present time. The observations are taken several times a week at the polar and mid latitudes and allow us to study dynamics of galactic and solar cosmic ray as well as secondary particle fluxes in the atmosphere and in the near-Earth space. Solar energetic particles (120) – mostly protons – (SEP) events with >100 MeV proton intensity above 1 cm−2 s−1 s−1 were recorded during 1958–2006. Before the advent of the SEP monitoring on spacecraft these results constituted the only homogeneous series of >100 MeV SEP events. The SEP intensities and energy spectra inferred from the Lebedev Physical Institute observations are consistent with the results taken in the adjacent energy intervals by the spacecraft and neutron monitors. Joint consideration of the SEP events series recorded by balloons and by neutron monitors during solar cycles 20–23 makes it possible to restore the probable number of events in solar cycle 19, which was not properly covered by observations. Some correlation was found between duration of SEP event production in a solar cycle and sunspot cycle characteristics. 相似文献
59.
X射线脉冲星脉冲到达航天器时间测量 总被引:3,自引:0,他引:3
X射线脉冲星脉冲到达时间(TOA)的空间测量是航天器自主导航和用脉冲星钟作航天器时间标准的基础.在简要介绍地面射电观测TOA测量方法基础上,重点研究了X射线脉冲星脉冲到达时间的空间测量方法和算法.讨论了利用X射线脉冲星辐射光子到达时间观测,建立X射线脉冲轮廓的方法;给出了通过观测得到的X射线脉冲轮廓与标准脉冲轮廓比较,精确确定TOA的测量方法和实用算法.讨论了削弱多普勒效应对TOA测量影响的方法. 相似文献
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