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991.
Y. Saito D. Akita H. Fuke I. Iijima N. Izutsu Y. Kato J. Kawada Y. Matsuzaka E. Mizuta M. Namiki N. Nonaka S. Ohta T. Sato M. Seo A. Takada K. Tamura M. Toriumi T. Yamagami K. Yamada T. Yoshida K. Matsushima S. Tanaka 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2012
Development of a balloon to fly at higher altitudes is one of the most attractive challenges for scientific balloon technologies. After reaching the highest balloon altitude of 53.0 km using the 3.4 μm film in 2002, a thinner balloon film with a thickness of 2.8 μm was developed. A 5000 m3 balloon made with this film was launched successfully in 2004. However, three 60,000 m3 balloons with the same film launched in 2005, 2006, and 2007, failed during ascent. The mechanical properties of the 2.8 μm film were investigated intensively to look for degradation of the ultimate strength and its elongation as compared to the other thicker balloon films. The requirement of the balloon film was also studied using an empirical and a physical model assuming an axis-symmetrical balloon shape and the static pressure. It was found that the film was strong enough. A stress due to the dynamic pressure by the wind shear is considered as the possible reason for the unsuccessful flights. A 80,000 m3 balloon with cap films covering 9 m from the balloon top will be launch in 2011 to test the appropriateness of this reinforcement. 相似文献
992.
T. Joseph W. Lazio R.J. MacDowall Jack O. Burns D.L. Jones K.W. Weiler L. Demaio A. Cohen N. Paravastu Dalal E. Polisensky K. Stewart S. Bale N. Gopalswamy M. Kaiser J. Kasper 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
The Radio Observatory on the Lunar Surface for Solar studies (ROLSS) is a concept for a near-side low radio frequency imaging interferometric array designed to study particle acceleration at the Sun and in the inner heliosphere. The prime science mission is to image the radio emission generated by Type II and III solar radio burst processes with the aim of determining the sites at and mechanisms by which the radiating particles are accelerated. Specific questions to be addressed include the following: (1) Isolating the sites of electron acceleration responsible for Type II and III solar radio bursts during coronal mass ejections (CMEs); and (2) Determining if and the mechanism(s) by which multiple, successive CMEs produce unusually efficient particle acceleration and intense radio emission. Secondary science goals include constraining the density of the lunar ionosphere by searching for a low radio frequency cutoff to solar radio emission and constraining the low energy electron population in astrophysical sources. Key design requirements on ROLSS include the operational frequency and angular resolution. The electron densities in the solar corona and inner heliosphere are such that the relevant emission occurs at frequencies below 10 MHz. Second, resolving the potential sites of particle acceleration requires an instrument with an angular resolution of at least 2°, equivalent to a linear array size of approximately 1000 m. Operations would consist of data acquisition during the lunar day, with regular data downlinks. No operations would occur during lunar night. 相似文献
993.
T Volk J D Rummel 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1987,7(4):141-148
Design decisions to aid the development of future space-based biological life support systems (BLSS) can be made with simulation models. Here we develop the biochemical stoichiometry for 1) protein, carbohydrate, fat, fiber, and lignin production in the edible and inedible parts of plants; 2) food consumption and production of organic solids in urine, feces, and wash water by the humans; and 3) operation of the waste processor. Flux values for all components are derived for a steady-state system with wheat as the sole food source. The large-scale dynamics of a materially-closed (BLSS) computer model is described in a companion paper. An extension of this methodology can explore multi-food systems and more complex biochemical dynamics while maintaining whole-system closure as a focus. 相似文献
994.
Sterken Veerle J. Baalmann Lennart R. Draine Bruce T. Godenko Egor Herbst Konstantin Hsu Hsiang-Wen Hunziker Silvan Izmodenov Vladislav Lallement Rosine Slavin Jonathan D. 《Space Science Reviews》2022,218(8):1-15
Space Science Reviews - The ESA Swarm mission, launched on 22 November 2013, consists of three spacecraft each equipped with a Micro Advanced Stellar Compass ( $\mu $ ASC) from the Technical... 相似文献
995.
The finite element algorithm developed by the authors has been used for solving the strength and stability problems of shells. The effect of deformation nonlinearity, stiffness of stringer set, shell thickness on critical loads has been determined. 相似文献
996.
This paper examines the impact of the external field intensity of white noise on the nonlinear dynamics of square plates under the longitudinal load. It is shown that in some cases, the noise of high intensity is able to reduce the number of frequencies in the oscillation spectrum of the system. 相似文献
997.
Peslier Anne H. Schönbächler Maria Busemann Henner Karato Shun-Ichiro 《Space Science Reviews》2017,212(1-2):811-811
Space Science Reviews - Correction to: Space Sci Rev DOI This article has been corrected. Figure 3 was initially published with erroneous axis titles in Fig. 3B and 3D where the $x$ axis should be... 相似文献
998.
999.
1000.
K E Carr J S McCullough P Brennan T L Hayes E J Ainsworth A C Nelson 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1994,14(10):521-530
The effects on 17 different structural parameters of mouse small intestine three days after treatment with three types of heavy ion (neon, iron and niobium) are compared, the first two being of particular relevance to space flight. The data for niobium are given in full, showing that changes after niobium ion treatment are not standard and are concentrated in the epithelial compartment, with few of the parameters having a response which is dose dependent. When comparisons are made for the three types of heavy ion, the damage is greatest after neon ion irradiation, implying that the additional non-epithelial damage produced as LET rises from X rays through neutrons to neon ions is not necessarily maintained as LET continues to rise. Further understanding is therefore needed of the balance between changes affecting the vascular and absorptive components of the organ. Variation from group to group is also important, as is variation of strain or gastrointestinal status. All such factors are important in the understanding of changes in multicellular organs after exposure to heavy ion radiation. 相似文献