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31.
An altitude profile of the ozone concentration from 55 to 95 km was measured at sunset in January by simultaneous measurements of the 1.27 μm radiation and the solar UV radiation using rocket-borne radiometers at Uchinoura, Japan (31°N). The ozone profiles deduced by two different methods agree with each other at approximately 70 km. The profile was consistent with our previous results obtained at the same station in September, and with the sunset profile obtained at Wallops Island (38°N) during the WMO/FAA/NASA international ozone rocketsonde intercomparison. Our data show no seasonal variation of ozone in the 55 – 95 km region at Uchinoura.  相似文献   
32.
利用导流装置降低大后壁车辆气动阻力的实验研究(Ⅰ)   总被引:3,自引:0,他引:3  
利用1/16缩比的公共汽车模型及两种类型的导流装置,在一带有可移动地面和边界层吸收装置的Eiffel型风洞中进行了在车辆后端面的上下边和侧边分别安装导流装置时车辆后部尾流区的压强恢复及气动阻力降低的实验。应用边界层分离理论比较详细地分析了安装导流装置的车辆后部尾流区的流动机理,综合分析评价了车辆表面与导流装置间的缝隙在空气引流及车辆气动阻力的降低中的作用,为新型车辆的设计和改造提供有利依据。  相似文献   
33.
Simulated planetary atmospheres (mixtures of simple gases) were irradiated with high energy particles to simulate an action of cosmic rays. When a mixture of carbon monoxide, nitrogen and water was irradiated with 2.8-40 MeV protons, a wide variety of bioorganic compounds including amino acids, imidazole, and uracil were identified in the products. The amount of amino acids was proportional to the energy deposit to the system. Various kinds of simulated planetary atmospheres, such as "Titan type" and "Jovian type", were also irradiated with high energy protons, and gave amino acids in the hydrolyzed products. Since cosmic rays are a universal energy source in space, it was suggested that formation of bioorganic compounds in planetary atmospheres is inevitable in the course of cosmic evolution.  相似文献   
34.
MAP-PACE (MAgnetic field and Plasma experiment—Plasma energy Angle and Composition Experiment) on SELENE (Kaguya) has completed its ~1.5-year observation of low-energy charged particles around the Moon. MAP-PACE consists of 4 sensors: ESA (Electron Spectrum Analyzer)-S1, ESA-S2, IMA (Ion Mass Analyzer), and IEA (Ion Energy Analyzer). ESA-S1 and S2 measured the distribution function of low-energy electrons in the energy range 6 eV–9 keV and 9 eV–16 keV, respectively. IMA and IEA measured the distribution function of low-energy ions in the energy ranges 7 eV/q–28 keV/q and 7 eV/q–29 keV/q. All the sensors performed quite well as expected from the laboratory experiment carried out before launch. Since each sensor has a hemispherical field of view, two electron sensors and two ion sensors installed on the spacecraft panels opposite each other could cover the full 3-dimensional phase space of low-energy electrons and ions. One of the ion sensors IMA is an energy mass spectrometer. IMA measured mass-specific ion energy spectra that have never before been obtained at a 100 km altitude polar orbit around the Moon. The newly observed data show characteristic ion populations around the Moon. Besides the solar wind, MAP-PACE-IMA found four clearly distinguishable ion populations on the dayside of the Moon: (1) Solar wind protons backscattered at the lunar surface, (2) Solar wind protons reflected by magnetic anomalies on the lunar surface, (3) Reflected/backscattered protons picked-up by the solar wind, and (4) Ions originating from the lunar surface/lunar exosphere.  相似文献   
35.
The high precision gamma-ray spectrometer (GRS) is scheduled to be launched on the lunar polar orbiter of the SELENE mission in 2007. The GRS consists of a large Ge crystal as a main detector and massive bismuth germanate crystals as an anticoincidence detector. A Stirling cryocooler was adopted in cooling the Ge detector. The flight model of SELENE GRS has been completed and an energy resolution of 3.0 keV (FWHM) at 1.332 MeV has been achieved. The spectrometer aims to observe nuclear line gamma rays emitted from the lunar surface in a wide energy range from 100 keV to 12 MeV for one year and more to obtain chemical composition on the entire lunar surface. The gamma-ray data enable us to study lunar geoscience problems including crust and mantle composition, and volatile reservoirs at polar regions.  相似文献   
36.
An increasing number of lunar base construction programs are in the process of developing lunar resources such as helium 3. The objective of the present work is to evaluate the temperature and humidity control system, which will allow man to live and work on the moon while developing lunar resources. The results of thermal load calculation show that the load of electric lighting is a 80 to 90% of the cooling load in the habitat module and that only the cooling function is required for temperature control. Due to this, a fluorocarbon refrigerant heat pump system was selected to satisfy reliability, energy consumption, size and weight requirements for the lunar base equipment. According to the load calculation, occupants will feel discomfort due to radiant heat from lighting fixtures. To resolve this problem, an air conditioning system, used in combination with forced convective cooling and panel cooling on the ceiling, was adopted in the living space. Moreover, the experiment on the ground was carried out to evaluate the effects of panel cooling.  相似文献   
37.
A new pseudonoise (PN) ranging system is proposed for trackingof deep space probes, named the dual speed PN ranging system,that transmits two different PN sequences simultaneously through a PSK/PSK (phase-shift keying) dual speed communication channel.The dual speed PN ranging system improves the maximummeasurable range significantly, with no degradation of theacquisition time, when compared with usual PN ranging systems.According to the analysis, the tracking error of this system becomesas small as those of usual PN ranging systems when the inputsignal-to-noise ratio (SNR) is large enough.  相似文献   
38.
The term “ultraviolet (UV) burst” is introduced to describe small, intense, transient brightenings in ultraviolet images of solar active regions. We inventorize their properties and provide a definition based on image sequences in transition-region lines. Coronal signatures are rare, and most bursts are associated with small-scale, canceling opposite-polarity fields in the photosphere that occur in emerging flux regions, moving magnetic features in sunspot moats, and sunspot light bridges. We also compare UV bursts with similar transition-region phenomena found previously in solar ultraviolet spectrometry and with similar phenomena at optical wavelengths, in particular Ellerman bombs. Akin to the latter, UV bursts are probably small-scale magnetic reconnection events occurring in the low atmosphere, at photospheric and/or chromospheric heights. Their intense emission in lines with optically thin formation gives unique diagnostic opportunities for studying the physics of magnetic reconnection in the low solar atmosphere. This paper is a review report from an International Space Science Institute team that met in 2016–2017.  相似文献   
39.
弯叶片对大转角平面涡轮叶栅气动性能影响的实验研究   总被引:2,自引:0,他引:2  
本文选择叶型折转角为113°的平面涡轮叶栅,开展了直叶栅、正,反弯曲叶栅的流场测量和流动显示研究,讨论了叶片弯曲对壁面流谱、静压分布以及流动损失的影响.结果表明:对于大折转角(113°)平面涡轮叶栅,叶片反弯(DHN)使得叶栅流场明显恶化,叶栅损失增加;叶片正弯(DHP)则在一定程度上减少流动损失,但效果没有普通小折转角的涡轮叶栅明显.  相似文献   
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