全文获取类型
收费全文 | 367篇 |
免费 | 34篇 |
国内免费 | 36篇 |
专业分类
航空 | 215篇 |
航天技术 | 87篇 |
综合类 | 27篇 |
航天 | 108篇 |
出版年
2022年 | 3篇 |
2021年 | 17篇 |
2020年 | 7篇 |
2019年 | 7篇 |
2018年 | 9篇 |
2017年 | 10篇 |
2016年 | 8篇 |
2015年 | 10篇 |
2014年 | 27篇 |
2013年 | 15篇 |
2012年 | 9篇 |
2011年 | 26篇 |
2010年 | 5篇 |
2009年 | 20篇 |
2008年 | 11篇 |
2007年 | 7篇 |
2006年 | 10篇 |
2005年 | 20篇 |
2004年 | 16篇 |
2003年 | 34篇 |
2002年 | 43篇 |
2001年 | 12篇 |
2000年 | 6篇 |
1999年 | 12篇 |
1997年 | 4篇 |
1996年 | 6篇 |
1995年 | 6篇 |
1994年 | 9篇 |
1993年 | 8篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1989年 | 7篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1978年 | 3篇 |
1975年 | 4篇 |
1973年 | 1篇 |
1972年 | 6篇 |
1971年 | 1篇 |
1970年 | 3篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1967年 | 4篇 |
1966年 | 2篇 |
1963年 | 2篇 |
1962年 | 1篇 |
排序方式: 共有437条查询结果,搜索用时 15 毫秒
101.
102.
103.
104.
105.
It is commonly believed that comets are made of primordial material. As a consequence, they can reveal more information about
the origin of our solar system. To interpret the coma composition measurements of comet Churyumov–Gerasimenko that will be
collected by the Rosetta mission, models of the coma chemistry have to be constructed. However, programming the chemistry
of a cometary coma is extremely complex due to the large number of species and reactions involved. Moreover, such a program
needs to be very flexible as one may want to extend, change, or update the set of species, reactions, and reaction rates.
Therefore, we developed software to manage a database of species and reactions and to generate code automatically to compute
source/loss balances. This database includes the data from the UMIST database and the ion–molecule reactions collected by
V.G. Anicich. To use all these databases together, a lot of practical problems need to be solved, but the result is an enormous
source of information about chemical reactions that can be used in chemical models, not only for comets but also for other
applications. 相似文献
106.
107.
L Narici V Bidoli M Casolino M P De Pascale G Furano A Morselli P Picozza E Reali R Sparvoli S Licoccia P Romagnoli E Traversa W G Sannita A Loizzo A Galper A Khodarovich M G Korotkov A Popov N Vavilov S Avdeev V P Salnitskii O I Shevchenko V P Petrov K A Trukhanov M Boezio W Bonvicini A Vacchi N Zampa R Battiston G Mazzenga M Ricci P Spillantini G Castellini P Carlson C Fuglesang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(1):141-146
The ALTEA project participates to the quest for increasing the safety of manned space flights. It addresses the problems related to possible functional damage to neural cells and circuits due to particle radiation in space environment. Specifically it aims at studying the functionality of the astronauts' Central Nervous Systems (CNS) during long space flights and relating it to the peculiar environments in space, with a particular focus on the particle flux impinging in the head. The project is a large international and multidisciplinary collaboration. Competences in particle physics, neurophysiology, psychophysiology, electronics, space environment, data analyses will work together to construct the fully integrated vision electrophysiology and particle analyser system which is the core device of the project: an helmet-shaped multi-sensor device that will measure concurrently the dynamics of the functional status of the visual system and passage of each particle through the brain within a pre-determined energy window. ALTEA is scheduled to fly in the International Space Station in late 2002. One part of the multi-sensor device, one of the advanced silicon telescopes, will be launched in the ISS in early 2002 and serve as test for the final device and as discriminating dosimeter for the particle fluences within the ISS. 相似文献
108.
109.
110.