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121.
介绍了A350XWB项目的近期发展状况,包括机身的重量验证试验、新的机组人员休息区的验证,尽早在项目前期进行验证以及从A380飞机吸取的教训。 相似文献
122.
崔健 《中国民航飞行学院学报》2013,(1):53-54
在我院使用的活塞发动机飞机中,点火系统故障率居高不下,其中又以电嘴积铅带来的发动机抖动故障居多。本文通过对比分析,以及实际监控使用的具体情况,证明了REM37BY电嘴能使这一故障大大减少,并且能节约成本,缩短工时,具有较大的推广价值。 相似文献
123.
空客A320飞机驾驶舱异响故障的排除 总被引:1,自引:0,他引:1
针对航线维护中一起不寻常的驾驶舱啸叫故障,参考空客公司的建议,结合实际航线维护经验,总结出系列驾驶舱异常噪声故障的可能来源,对类似故障的排除和隔离具有一定的参考意义。 相似文献
124.
传统的水族箱在进行加氧时具有机械性,需要多次的人工开停操作,已不适应现代的生活方式。本文介绍了一种由TH-2型水氧传感器,51单片机,模数转换器及其外围电路组成的水族箱自动加氧系统,实验证明该系统具有优良的性能和简捷的操作,节省了人工和电耗。 相似文献
125.
This article studies the effects of the CeCl3 concentrations in conversion solutions with and without addition of NaCl, pH-values of conversion solution, drying temperature, time and temperature of immersion on the Ce-conversion coatings for corrosion protection of the SiCp/5A06 Al-MMC and 5A06 Al-alloy in the 3.5% NaCl aqueous solution at room temperature. Potentiodynamic polarization tests reveal that the Ce-conversion treatment could markedly improve the pitting corrosion resistance of the composite and the matrix alloy in chloride containing environment. The best corrosion resistance effects are obtained for the samples treatment in 1‰ CeCl3·7H2O/ 3.5% NaCl solution at 45 °C for 60 min, followed by drying at 100 °C for 30 min. Examinations by means of scanning electron microscopy (SEM), energy dispersion spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) indicate that this behavior is due to the precipitation of Ce-oxides/hydroxides on the cathodic intermetallics and the Al-oxide film on the rest of the metal matrix. 相似文献
126.
L. Foschini L. Maraschi F. Tavecchio G. Ghisellini M. Gliozzi R.M. Sambruna 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
It has been suggested that some radio-loud narrow-line Seyfert 1 contain relativistic jets, on the basis of their flat-spectrum radio nuclei and studies on variability. We present preliminary results of an ongoing investigation of the X-ray and multiwavelength properties of 5 radio-loud NLS1 based on archival data from Swift and XMM-Newton. Some sources present interesting characteristics, very uncharacteristic for a radio-quiet narrow-line Seyfert 1, such as very hard X-ray spectra, and correlated optical and ultraviolet variability. However, none of the studied sources show conclusive evidence for relativistic jets. γ-Ray observations with Fermi are strongly recommended to definitely decide on the presence or not of relativistic jets. 相似文献
127.
J.-C. Liou N.L. Johnson 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The intentional breakup of Fengyun-1C on 11 January 2007 created the most severe orbital debris cloud in history. The altitude where the event occurred was probably the worst location for a major breakup in the low Earth orbit (LEO) region, since it was already highly populated with operational satellites and debris generated from previous breakups. The addition of so many fragments not only poses a realistic threat to operational satellites in the region, but also increases the instability (i.e., collision cascade effect) of the debris population there. 相似文献
128.
A.A. de Almeida R. Boczko G.C. Sanzovo D. Trevisan Sanzovo 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
We developed a general method for determination of water production rates from groundbased visual observations and applied it to Comet Hale–Bopp. Our main objective is to extend the method to include total visual magnitude observations obtained with CCD detector and V filter in the analysis of total visual magnitudes. We compare the CCD V-broadband careful observations of Liller [Liller, W. Pre-perihelion CCD photometry of Comet 1995 O1 (Hale-Bopp). Planet. Space Sci. 45, 1505–1513, 1997; Liller, W. CCD photometry of Comet C/1995 O1 (Hale-Bopp): 1995–2000. Int. Comet Quart. 23(3), 93–97, 2001] with the total visual magnitude observations from experienced international observers found in the International Comet Quarterly (ICQ) archive. A data set of ∼400 CCD observations covering about the same 6 years time span of the ∼12,000 ICQ selected total visual magnitude observations were used in the analysis. A least-square method applied to the water production rates, yields power laws as a function of the heliocentric distances for the pre- and post-perihelion phases. The average dimension of the nucleus as well as its effective active area is determined and compared with values published in the literature. 相似文献
129.
用柠檬酸法、固相法制备了替代的复合氧化物La1-xCaxFeO3及La1-xCaxMnO3。对样品进行了XRD及导电能力测试。结果表明:X≤0.5,复合氧化物为单相的钙钛矿结构;Ca的掺入,改善了LaFeO3导电性能,使其室温电阻率从6×10^4Ω·cm降低到10Ω·cm左右;而对LaMnO3的影响不大,其室温电阻率在10^-1Ω·cm左右。 相似文献
130.
基于CS8900A的工业级嵌入式网络接口实现 总被引:2,自引:0,他引:2
介绍了工业级以太网络控制芯片CS8900A—IQ3在嵌入式Internet中的应用,以实例详细对比说明了其在8位和16位两种运行模式下的硬件和软件实现。 相似文献