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941.
《海洋学报(英文版)》2014,(6):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,hydrology,meteorology,geology,engineering,remote sensing,etc.Progress reports on research projects are also included.  相似文献   
942.
《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,  相似文献   
943.
《海洋学报(英文版)》2014,(10):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,  相似文献   
944.
《海洋学报(英文版)》2014,(5):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,hydrology,meteorology,geology,engineering,remote sensing,etc.Progress reports on research projects are also included.  相似文献   
945.
<正>《极地研究》是集中反映南北极多学科考察研究成果的综合性学术刊物。它是极地科学工作者发表最新研究成果的园地,也是进行国际国内极地考察研究学术交流的窗口。本刊主要刊登以极地为研究对象或以极地为探测平台的堪础研究、应用研究和高技术研究成果,反映该领域的新发现、新创造、新理论和新方法。具体报道范围包括极地冰川学、极地海洋科学、极地大气科学、极  相似文献   
946.
<正>《极地研究》是集中反映南北极多学科考察研究成果的综合性学术刊物。它是极地科学工作者发表最新研究成果的园地,也是进行国际国内极地考察研究学术交流的窗口。本刊主要刊登以极地为研究对象或以极地为探测平台的基础研究、应用研究和高技术研究成果,反映该领域的新发现、新创造、新理论和新方法。具体报道范围包括极地冰川学、极地海洋科学、极地大气科学、极区空间物理学、极地地质学、极地地球物理学、极地地球化学、极地生物与生态学、极地医学、南极天文学,极  相似文献   
947.
Soil salinization research in China: Advances and prospects   总被引:14,自引:0,他引:14  
With the environmental deterioration caused by the advance of climate change, soil salinization is a serious and growing global problem. Currently about 7% of the world's land surface is threatened by salinization. China is a country whose soils are severely affected by this problem, which, due to its extensive area, and wide distribution poses a serious threat to regional agricultural development. In this review, we summarize the framework for soil salinization research in China over the past 70 years, assess the weaknesses of existing research in both a domestic and international context, highlight the trends and key findings of global research about saline soils over the past 30 years, and propose six major fields and directions for future research on saline soil.  相似文献   
948.
城市影响范围的界定是研究城市与周围城市、区域之间相互作用的一个重要内容,对城市和区域的规划有着重要意义。该文选取20项能反映城市影响范围的相关指标,通过主成分分析及数据变换,确定了京津冀三地14个地市的中心性强度。有效结合断裂点理论与加权Voronoi图方法,界定并生成了该地区各地市的影响范围。改进现有的确定区域中心城市和划分城市经济影响区的方法,在分析基于断裂点理论的加权Voronoi图网格包含与邻接关系的基础上,将京津冀地区划分为3个城市群,确定了3个1级中心城市、2个2级中心城市。  相似文献   
949.
<正>包头市国土资源局把维护群众权益更加有力有效作为工作的出发点,切实保障被征地农民的合法权益,对征地明确提出"四个不报批",即"凡不在土地利用总体规划确定的建设用地范围内的各类开发区、园区及城市建设用地一律不报批;凡没在土地利用年度计划指标的一律不报批;凡不符合国家产业  相似文献   
950.
Certain feasibilities and features were discussed in typhoon detection by radar with a negative elevation angle according to the relationship between the remote detecting range and the elevation angle of the new generation weather radar, in order to rectify the disadvantages of detecting capability for remote low-level echo with a lowest elevation angle of 0.5° in the common detecting mode. The data obtained from detecting the typhoon of Haitang and Changmi with radar for their negative elevation angles and the observed data for the common lowest elevation angle of 0.5° were compared to each other. The results showed that the detection of remote low level cloud system with radar could be improved by using the negative elevation angle, and the structure and the evolution trend of a typhoon could be better judged. The increasing degree of detection for negative elevation angles in the current volume scanning mode should be helpful for predicting the intensity and developing trend of windstorms, to further improve the capability of warning and nowcasting. The detection of negative elevation angle could also help reveal the development and change of typhoon's low level cloud system. As far as the typhoons of Haitang and Changmi were concerned, the detecting area of Changmi was increased by 1.09 times with the negative elevation angle of 0.31°, compared with the elevation angle of 0.48° if the threshold value for the sea echo within 100 km was eliminated. Several volume scans of Haitang were increased by 2.1%-7.9% for the negative elevation angle of 0.36° compared with the elevation angle of 0.49° . Therefore, the radar detecting capability of typhoons could be improved by the detection of negative elevation angles to some extent. This could make up for the disadvantages of a low detecting capability for remote low-level echo in the common detecting mode. At the same time, a negative elevation angle could be easily influenced by the ground clutter and the close sea wave clutter which interfered with the asses  相似文献   
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