共查询到20条相似文献,搜索用时 62 毫秒
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无论从国民经济实力、还是从经济发展的需求,中国都应该能够成为世界公务机市场非常重要的一极,然而事实远非如此。在过去两年中,中国公务机市场虽有转暧的迹象,但距繁荣仍有相当距离。 相似文献
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薛莲%扈艳红%沈学宁%黄发荣%杜磊 《宇航材料工艺》2006,36(2):38-40
初步研究了N,N,N’,N’-四炔丙基-4,4’-二氨基-二苯甲烷(TPDDM)的热固化反应。通过DSC分析其固化行为特征。FT-IR观察了它固化过程中特征官能团变化,对比了其在空气中和氮气中固化行为的差异,发现在空气中固化产物出现1733cm^-1的峰,推断是被氧化所致,并通过DSC和FT-IR确定了固化条件。利用TGA技术考察了该固化产物在空气中和氮气中的热稳定性。结果表明:在空气中固化产物起始失重率为5%的分解温度为414.4℃,高于在氮气中的392.8℃。TPDDM的固化产物在氮气中700℃残碳率为53.9%,在空气中全部分解。 相似文献
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《Aerospace and Electronic Systems Magazine, IEEE》2008,23(7):46-46
The editors have collected a comprehensive set of monographs that provide insight into the more recent history of bistatic radar design and implementation. This volume combines improved details of the environment along with novel system applications. Each chapter is authored by radar experts who had the vision and motivation to tackle a daunting development problem, and share their view of the successes and remaining implementation challenges. The book is divided into two parts: Bistatic/Multistatic Systems and Bistatic Clutter and Signal Processing. The book is an essential addition to the modern radar engineer's library. 相似文献
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Space Science Reviews - 相似文献
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Space Science Reviews - 相似文献
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J. Kleczek 《Space Science Reviews》1999,87(3-4):545-546
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J. Kleczek 《Space Science Reviews》1999,89(3-4):689-689
The reviewed Volumes of the AAA series record, summarize and index nearly 12 000 papers covering all aspects of astronomy
and space sciences, published throughout the world during the first half of the year 1998.
The AAA series is the most important source of information on progress in the scientific disciplines. They have become an
indispensable source of information for scientists and students involved in the Universe research.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Space Science Reviews - 相似文献
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Space Science Reviews - 相似文献
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Space Science Reviews - 相似文献
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金属切削过程中,造成刀具磨损的主要原因是刀具和工件之间的接触和摩擦以及刀刃附近高温高压的极端恶劣的条件.切削区域任何一个单元接触条件的改变都会影响刀具的磨损,这些条件主要包括刀具材料、刀具涂层以及刀具几何规格,其他条件还有工件材料及其物理性能,刀具参数和合适的切削条件,冷却润滑条件,切削过程中机床振动较大或刀跳较严重时导致刀具出现波动的过载等. 相似文献
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主要引进了Nκ-投射半模的概念,并结合环中投射模与半环中投射半模的性质,得到了关于Nκ-投射半模的一些性质,这些性质是投射模与投射半模性质的推广。 相似文献
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Space Science Reviews - 相似文献
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