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Chinese Academy of Sciences Institutional Repositories Grid
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浏览/检索结果: 共6条,第1-6条 帮助

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Response of soil aggregate stability and splash erosion to different breakdown mechanisms along natural vegetation restoration 期刊论文  OAI收割
CATENA, 2022, 卷号: 208, 页码: 8
作者:  
Ma, Rentian;  Hu, Feinan;  Xu, Chenyang;  Liu, Jingfang;  Zhao, Shiwei
  |  收藏  |  浏览/下载:32/0  |  提交时间:2022/09/21
Factors controlling spatial variation in soil aggregate stability in a semi-humid watershed 期刊论文  OAI收割
SOIL & TILLAGE RESEARCH, 2021, 卷号: 214, 页码: 10
作者:  
Zhang, Pingping;  Wang, Yunqiang;  Xu, Lan;  Li, Ruijie;  Sun, Hui
  |  收藏  |  浏览/下载:48/0  |  提交时间:2021/12/07
Physicochemical determinants in stabilizing soil aggregates along a hydrological stress gradient on reservoir riparian habitats: Implications to soil restoration 期刊论文  OAI收割
ECOLOGICAL ENGINEERING, 2020, 卷号: 143, 页码: 9
作者:  
Ran, Yiguo;  Ma, Maohua;  Liu, Yan;  Zhu, Kai;  Yi, Xuemei
  |  收藏  |  浏览/下载:18/0  |  提交时间:2020/08/24
Nitrogen addition increases the contents of glomalin-related soil protein and soil organic carbon but retains aggregate stability in a Pinus tabulaeformis forest 期刊论文  OAI收割
PEERJ, 2018, 卷号: 6
作者:  
Hang Jing;  Lipeng Sun;  Guoliang Wang;  Guobin Liu;  Liu, GB (reprint author), Northwest A&F Univ, Inst Soil & Water Conservat, Yangling, Shaanxi, Peoples R China.
  |  收藏  |  浏览/下载:48/0  |  提交时间:2018/09/25
Soil Aggregate Stability and Iron and Aluminium Oxide Contents Under Different Fertiliser Treatments in a Long-Term Solar Greenhouse Experiment 期刊论文  OAI收割
PEDOSPHERE, 2016, 期号: 5, 页码: 760-767
作者:  
Yin Yan;  Wang Li;  Liang Chenghua;  Xi Fengming;  Pei Zhongjian
收藏  |  浏览/下载:27/0  |  提交时间:2016/12/05
Research on the support structure of the primary mirror of large-aperture telescope (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China
Yang W.; Jingxu Z.
收藏  |  浏览/下载:21/0  |  提交时间:2013/03/25
Large-aperture telescope can be used in surveying battlefield  researching landform  searching object  real-time monitoring  imaging  detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important role in military conflicts. The orbit parameter of object  quantity  geometrical shape parameter and so on can be obtained by detect spatial target. With the development of optical technology  people require larger aperture in optics-electronic (OE) system. By increasing optical aperture  the ability of collecting light and resolution power in the system can be enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem. With the increase of primary mirror aperture  the weight of the primary mirror will become larger than before. The root mean square (rms) of the primary mirror is affected by many factors  such as deadweight  deformation of heat  environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By reducing the weight of primary mirror  precision of the system is ensured. During the designing phase  one can consider the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of optical system and the effect factors. The final structural design can be reasonable. In an astronomical telescope  the surface of reflector is an important part for collecting dark radiation of celestial bodies. Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very high. Optical system of large aperture  small wavelength and small focus can receive maximal light intensity. For ground-based optical astronomical telescope  the design proposed in the paper can satisfy the requirement of the possible minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the angle diameter range of the minimum atmosphere seeing  then 100% of light energy should be focused on the angle diameter range of minimum atmosphere seeing. Because the rms of mirror is very high  precise surface machining and accurate the support of mirror are very important tasks during designing and manufacturing the telescope. In the paper  various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter telescope system at the Starfire Optical Range (SOR) overviewed simply  which was operated by the Directed Energy Directorate of the Air Force Research Laboratory  Kirtland AFB  NM  USA from the ground-based O-E system for the observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter mirror is analyzed.