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71.
China Satellite Navigation Conference,CSNC 2015 was held in Xi’an on May 13-15.During the conference the attendants mentioned frequently the strategic significance of integrating the Bei Dou system into the Silk Road Economic Belt and the 21 Century Maritime Silk Road("Belt and Road")Initiative.  相似文献   
72.
柔性接头用低模量硅橡胶配方及界面粘接技术研究   总被引:1,自引:0,他引:1  
研究了硫化剂、增粘剂和补强填料等组分对一种低模量、低硬度和高强度的硅橡胶配方力学性能的影响规律,同时研究了一种胶粘剂配方来满足硅橡胶与金属钢界面粘接的工艺要求。该硅橡胶配方的剪切模量小于0.3MPa,与钢界面粘接的剪切强度大于2.5MPa,满足柔性接头部件的性能要求。  相似文献   
73.
硬质泡沫喷管堵盖试验及研究   总被引:1,自引:0,他引:1  
介绍了固体火箭发动机喷管硬质泡沫塑料堵盖的设计方法与试验过程。某型号发动机硬质泡沫喷管堵盖打开压强模拟点火试验结果表明,这种硬质泡沫喷管堵盖设计方案可行。并已在实际中得到应用。  相似文献   
74.
固体火箭羽焰的辐射特性及其温度测量技术述评   总被引:9,自引:1,他引:8  
叙述了固体火箭羽焰的辐射特性,简要地介绍了热电偶法、等离子体法、光纤测温法、谱线反转法、发射吸收法、喇曼光谱法、微波衰减法、红外测温法和多光谱测温法的原理和应用。评述了这些火焰测温方法在羽焰测温上的适应性,并指出多光谱测温技术是羽焰测温的发展趋势之一。  相似文献   
75.
Like the other great space powers of the 21st century, Europe has its own means of accessing space: Ariane, which has guaranteed its independence in the launching of civil and military satellites for almost 30 years and has won a significant part of the highly competitive commercial market. This market provides the Ariane system with the production volume indispensable for its reliability, which also benefits institutional launches. Europe's commercial market share will be even larger if the launch system is flexible and adaptable to the diversity of demand. Probable future technological changes make flexibility more necessary still. Two technical characteristics will be key: a large enough payload capacity and the injection of satellites into energetic orbits, including final geostationary orbit. But carrying out such missions will only be possible if a new generation upper stage is used. The November 2008 ESA ministerial meeting opted to wait until 2011 to decide whether this is necessary, making it doubtful whether Arianespace will be able to maintain leadership in the commercial market. The authors urge a rethink of this position.  相似文献   
76.
PAMELA is a multi-purpose apparatus composed of a series of scintillator counters arranged at the extremities of a permanent magnet spectrometer to provide charge, time-of-flight and rigidity information. Lepton/hadron identification is performed by a silicon–tungsten calorimeter and a Neutron detector placed at the bottom of the device. An Anticounter system is used offline to reject false triggers coming from the satellite. The device was put into orbit on June 15th 2006 in a pressurized container on board the Russian Resurs-DK1 satellite. The satellite is flying along a high inclination (70°), low Earth orbit (350–600 km), allowing to perform measurements in different points and conditions of the geomagnetosphere. PAMELA main goal is a precise measurement of the antimatter ( 80 MeV–190 GeV, e+ 50 MeV–270 GeV) and matter (p 80–700 GeV, e 50 MeV–400 GeV) component of the galactic cosmic rays. In this paper we focus on the capabilites of observations of heliospheric cosmic rays: trapped and semi-trapped particles in the proton and electron belts, solar particle events, Jovian electrons will be studied in the three years of expected mission.  相似文献   
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