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61.
《Space Policy》2014,30(3):156-162
The development of the Global Exploration Roadmap (GER) by 12 space agencies participating in the International Space Exploration Coordination Group broadly outlines a pathway to send humans beyond low Earth orbit for the first time since Apollo. Three themes have emerged: Exploration of a Near-Earth Asteroid, Extended Duration Crew Missions, and Humans to the Lunar Surface. The lack of detail within each of these themes could mean that realizing the goals of the GER would be significantly delayed. The purpose of this paper is to demonstrate that many of the details needed to fully define and evaluate these themes in terms of scientific rationale, economic viability, and technical feasibility already exist and need to be mapped to the GER. Here, we use the Humans to the Lunar Surface theme as an example to illustrate how this process could work. By mapping documents from a variety of international stakeholders, this process can be used to cement buy-in from the current partners and attract new ones to this effort.  相似文献   
62.
The soil carbon content and its relation to site characteristics are important in evaluating current local, regional, and global soil C storage and projecting future variations in response to climate change. In this study we analyzed the concentration of organic and inorganic carbon and their relationship with in situ climatic and geological characteristics in 485 samples of surface soil and 17 pits from the hyper-arid area and 51 samples with 2 pits from the arid–semiarid region from the Atacama Desert located in Peru and Chile. The soil organic carbon (SOC) in hyperarid soils ranged from 1.8 to 50.9 μg C per g of soil for the 0–0.1 m profile and from 1.8 to 125.2 μg C per g of soil for the 0–1 m profile. The analysis of climatic (temperature and precipitation), elevation, and some geologic characteristics (landforms) associated with hyper-arid soils explained partially the SOC variability. On the other hand, soil inorganic carbon (SIC) contents, in the form of carbonates, ranged from 200 to 1500 μg C per g of soil for the 0–0.1 m profile and from 200 to 3000 μg C per g of soil for the 0–1.0 m profile in the driest area. The largest accumulations of organic and inorganic carbon were found near to arid–semiarid areas. In addition, the elemental carbon concentrations show that the presence of other forms of inorganic carbon (e.g. graphite, etc.) was negligible in these hyperarid soils. Overall, the top 1 m soil layer of hyperarid lands contains ∼11.6 Tg of organic carbon and 344.6 Tg of carbonate carbon. The total stored carbon was 30.8-fold the organic carbon alone. To our knowledge, this is the first study evaluating the total budget carbon on the surface and shallow subsurface on ∼160,000 km2 of hyperarid soils.  相似文献   
63.
Melting sulfur and mixing it with an aggregate to form “concrete” is commercially well established and constitutes a material that is particularly well-suited for use in corrosive environments. Discovery of the mineral troilite (FeS) on the moon poses the question of extracting the sulfur for use as a lunar construction material. This would be an attractive alternative to conventional concrete as it does not require water. However, the viability of sulfur concrete in a lunar environment, which is characterized by lack of an atmosphere and extreme temperatures, is not well understood. Here it is assumed that the lunar ore can be mined, refined, and the raw sulfur melded with appropriate lunar regolith to form, for example, bricks. This study evaluates pure sulfur and two sets of small sulfur concrete samples that have been prepared using JSC-1 lunar stimulant and SiO2 powder as aggregate additions. Each set was subjected to extended periods in a vacuum environment to evaluate sublimation issues. Results from these experiments are presented and discussed within the context of the lunar environment.  相似文献   
64.
The ancient Greek astronomical calculator known as the Antikythera Mechanism has been analyzed using geometrical, calculus, trigonometric and complex variable methods. This analysis demonstrates that the Mechanism modeled the variations in the Moon’s angular velocity as seen from the Earth, to better than 1 part in 200. A major implication of this analysis is that the Antikythera Mechanism of the 2nd century BCE modeled the anomalistic motion of the Moon more accurately than Ptolemy’s account of Hipparchus’s theory of the 2nd century CE. In the present work, mathematics, astronomy, history and methodology of the sciences combine in the study of a unique artifact, preserved for posterity in an ancient ship that sank in the Mediterranean 2100 years ago and recovered by Greek sponge divers at the dawn of the 20th century.  相似文献   
65.
基于3层B/S结构的月球资源数据库系统的设计与实现   总被引:1,自引:0,他引:1  
基于3层B/S结构,采用Web技术,在Intranet环境下设计并开发了月球资源数据库系统,该系统实现了月球资源信息的管理,具有高效、使用方便,运行稳定可靠等特点,并具有良好的可扩充性和可维护性。  相似文献   
66.
对国外极月轨道月球卫星的热设计进行了概述,并以一个极月轨道月球卫星为例,介绍了采用单自由度太阳帆板技术的某极月轨道月球卫星.针对该卫星,对其奔月飞行和在极月轨道上环月运行时的外热流与空间散热问题进行分析,根据分析结果,初步提出了该卫星的热设计方案,重点对有效载荷热控问题, ±y侧仪器设备的热控问题,以及热控百叶窗的应用技术等进行了描述.  相似文献   
67.
月球卫星轨道设计优化   总被引:1,自引:0,他引:1  
利用带谐项J2和J3对月球卫星轨道进行了优化设计.首先分析了月球卫星轨道摄动因素对轨道的影响,其次推导了对应于J2和J3项的冻结轨道计算公式,并通过对仅包含月球引力场模型的运动微分方程,直接积分计算轨道的变化进行了验证.最后,通过合理选择初始轨道的偏心率e0和近月点幅角ω0,对月球卫星极轨道进行了优化设计,给出了设计公式并进行了仿真.结果表明,这种优化设计方法是很有效的.  相似文献   
68.
In this presentation, technological progress for China's microwave remote sensing is introduced. New developments of the microwave remote sensing instruments for China's lunar exploration satellite (Chang'E-1), meteorological satellite FY-3 and ocean dynamic measurement satellite (HY-2) are reported.  相似文献   
69.
The paper presents a conceptual configuration of the lunar base bioregenerative life support system (LBLSS), including soil-like substrate (SLS) for growing plants. SLS makes it possible to combine the processes of plant growth and the utilization of plant waste. Plants are to be grown on SLS on the basis of 20 kg of dry SLS mass or 100 kg of wet SLS mass per square meter. The substrate is to be delivered to the base ready-made as part of the plant growth subsystem. Food for the crew was provided by prestored stock 24% and by plant growing system 76%. Total dry weight of the food is 631 g per day (2800 kcal/day) for one crew member (CM). The list of candidate plants to be grown under lunar BLSS conditions included 14 species: wheat, rice, soybean, peanuts, sweet pepper, carrots, tomatoes, coriander, cole, lettuce, radish, squash, onion and garlic. From the prestored stock the crew consumed canned fish, iodinated salt, sugar, beef sauce and seafood sauce. Our calculations show that to provide one CM with plant food requires the area of 47.5 m2. The balance of substance is achieved by the removal dehydrated urine 59 g, feces 31 g, food waste 50 g, SLS 134 g, and also waters 86 g from system and introduction food 236 g, liquid potassium soap 4 g and mineral salts 120 g into system daily. To reduce system setup time the first plants could be sowed and germinated to a certain age on the Earth.  相似文献   
70.
Gamma-ray spectrometer (GRS) is included in the payload of Chinese first lunar mission Chang’E-1 that will be launched in 2007. Specific objectives of the GRS are to map abundance of O, Si, Fe, Ti, U, Th, K, and perhaps, Mg, Al, and Ca to depths of about 20 cm. There are remarkable advantages for GRS application to remote sensing elemental materials over the entire lunar surface: large effective area and good ability for background rejection. We will describe the design of GRS and present its performance in this paper. Moreover, the GRS calibration will also be introduced.  相似文献   
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