排序方式: 共有17条查询结果,搜索用时 31 毫秒
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Zheng Tianliang Wang Yuehong Zheng Kuangyu Li Qian Tao Ye 《中国航空学报》2007,20(6):559-563
Micro-coiled chiral carbon fibers are modified by nano-Ni. X-ray diffraction (XRD) and scanning electron microscopy (SEM) are used to compare the composition and morphology of the unmodified and the modified fibers. The results show that electromagnetism parameters of the modified are different from those of the unmodified. After modification by nano-Ni, the micro-coiled chiral carbon fibers have decreased permittivity and electrical loss. The permeability and magnetic loss of the modified carbon fibers become larger than those of the unmodified ones. Moreover, the modification of unmodified chiral carbon fibers into the modified is much like changing hollow electric windings into those with magnetic cores inside. The modifier intensifies the cross polarization of the chiral carbon fibers and makes the permittivity and the permeability get closer to each other which improves the matching performance and enhances absorbability of coatings. In the range of 6-18 GHz, the reflectivity of the coating is 6-8dB and the bandwidth is 12 GHz. The area density of the coating is below 3 kg/m^2. 相似文献
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高培仁 《民用飞机设计与研究》2012,(2):35-39
波音737-200是美国波音公司为满足当时短程航线的需要而研制的双发涡扇短程运输机。该机能在未经铺筑的跑道或砂石跑道上起落。主要措施为:在前轮处装上碎石偏转挡板;主起落架两轮之间装上挡板保护导管与减震支柱;在进气口前下方安装一根喷气管,向下喷出从压气机引出的高压空气以破坏地面涡流,防止小石子被吸进发动机。 相似文献
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纤维复合材料在先进防空导弹贮运发射箱上的应用 总被引:1,自引:0,他引:1
介绍了可用于先进防空导弹贮运发射箱的纤维复合材料、先进防空导弹贮运发射箱的性能发展和对结构材料的要求,论述了纤维复合材料贮运发射箱的结构方案和关键技术问题的解决途径。 相似文献
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