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911.
912.
中带蛤科(Mesodesmatidae)是蛤蜊总科(Mactracea)中种数较少的一科。中国科学院海洋研究所历年来在我国沿海潮间带采到一定数量的标本,经鉴定共5种(其中1新种),分隶于4个属,种名如下:(*为我国首次记录)。
1.环纹坚石蛤Atactodea striata (Gmelin)
*2.扁平蛤Davila planum (Hanley)
*3.反凸息蛤(新种) Anapella retroconvexa sp. nov.
4.中国朽叶蛤Coecella chinensis Deshayes
5.锈色朽叶蛤Coecella turgida Deshayes
中国近海的中带蛤过去报道较少,Deshayes(1854)报道Coecella chinensis产于中国近海; Kuroda(1941)报道产于我国台湾省的C. chinensis, C. cf. turgida和Amphidesma(Atactodea) striatum等3种;张玺等(1960,1961)报道C. chinensis和Mesodesma striata等2种。 相似文献
913.
地理课堂新授课教学中如何提升讲解技能以有效地突出重点、化解难点,是摆在大多数职初地理教师面前的难题。化解此难题有很多策略,本文从教学设计优化的视角,阐述讲解技能提升的基础——目标设定和路径优选,帮助职初教师顺利进行地理教学实践。 相似文献
914.
弱天气尺度强迫背景下的长江中下游暖区暴雨突发性强,高度非线性,难以准确预报,这时考虑不确定因素的集合预报成为重要选项,而对流尺度集合预报核心问题是积分一段时间后离散度偏低,会导致预报失败。比较包含不同尺度扰动信息的对流尺度集合预报方案间的差异性并据此优化初始扰动方案,针对2018年5月4—5日一次典型长江中下游暖区暴雨过程,分别采用动力降尺度(DOWN)、增长模繁殖法(BGM)、局地增长模繁殖法(LBGM)和混合扰动法(BLEND)等四种方法进行集合预报试验,以期探讨对离散度和预报效果的影响。结果表明,在模式积分0~6 h,具有中小尺度扰动信息的BGM和LBGM的离散度优于DOWN,其中LBGM相比于BGM具有一定程度上的改进,说明具有更准确中尺度特征的扰动能够在积分初始阶段获得有效增长,即考虑了中小尺度天气系统局地性的LBGM能弥补BGM的不足;但是,在模式积分12 h以后,具有更多大尺度特征扰动的DOWN优于区域模式中的增长模繁殖法BGM和LBGM,说明经过初始误差快速增长一段时间后,大尺度扰动开始起主要作用。而具有不同尺度扰动信息的BLEND方案则兼具LBGM和DOWN的优势,几乎在整个预报时段离散度较高且概率预报评分较好,体现出混合扰动的优越性。以上结果进一步说明,初始扰动的尺度特征在暖区暴雨的集合预报效果中具有关键性的作用,因而通过调整初始扰动的尺度信息来优化集合预报性能的混合扰动思想,在业务上具有一定的指导意义和推广价值。 相似文献
915.
Strategy Analysis of the Marine Science Projects of National Science Foundation of the United States
The National Science Foundation (NSF) is an international research funding institution with significant influence. As one of the main bodies of marine science research grant, NSF plays nonsubstitutable role in the development of marine science, the establishment of international research programs and projects, and the construction of infrastructures in the marine field. By mainly analyzing the area focus of NSF support, grant distribution and change trend, project application and acceptance rate in recent years, we summarized its funding characteristics and trends in marine science, and finally put forward four suggestions for reference to the efficient management of China's funding institutions. 相似文献
916.
Dong Wenjie Yuan Wenping Teng Fei Hao Zhixin Zheng Jingyun Wei Zhigang Chou Jieming Liu Changxin Qi Tianyu Yang Shili Yan Dongdong Zhang Jing 《地球科学进展》2016,31(12):1215-1219
According to the guideline of National Key Research and Development Project, this project aims at developing a world-class Integrated Assessment Model (IAM) in China, which will be used to assess the impacts of climate change on economy system. The objects of this project are to ① Improve the spatial resolution of Earth System Model (ESM); ② Modify the Integrated Assessment Model; ③ Couple the ESM and IAM; ④ Evaluate the impacts of climate change on society and economy. This project will solve two key scientific questions: how to identify the impacts of climate change in the IAM; How much the impacts of climate change on economy in China. Meanwhile, two techniques will be developed to complete the mission of this project: Simulate of small-scale human activities in the EAM and spatial and temporal resolution match of ESM and IAM. 相似文献
917.
Canada is a typical maritime country, fisheries economic prosperity and marine sustainable development have been the main management and research work. From two perspectives of research literatures and latest strategic plans, this paper studied the ocean research priorities and hot trends of Canada. The study found that the marine science and technology in Canada focuses on marine populations and ecosystems, protection of the marine environment and species, marine monitoring and data information, marine technology and management tools, Climate change and arctic research, deep-sea material energy and driving mechanisms. In the future, Canada will continue further study on arctic research, global warming, ecosystem monitoring, deep-sea exploration, marine new energy and new technologies. In summary, Canada’s research situations and development trends may provide a useful reference to China’s development of the marine industry. 相似文献
918.
919.
A multivariate statistical downscaling method is developed to produce regional, high-resolution, coastal surface wind fields based on the IPCC global model predictions for the U.S. east coastal ocean, the Gulf of Mexico(GOM), and the Caribbean Sea. The statistical relationship is built upon linear regressions between the empirical orthogonal function(EOF) spaces of a cross- calibrated, multi-platform, multi-instrument ocean surface wind velocity dataset(predictand) and the global NCEP wind reanalysis(predictor) over a 10 year period from 2000 to 2009. The statistical relationship is validated before applications and its effectiveness is confirmed by the good agreement between downscaled wind fields based on the NCEP reanalysis and in-situ surface wind measured at 16 National Data Buoy Center(NDBC) buoys in the U.S. east coastal ocean and the GOM during 1992–1999. The predictand-predictor relationship is applied to IPCC GFDL model output(2.0?×2.5?) of downscaled coastal wind at 0.25?×0.25? resolution. The temporal and spatial variability of future predicted wind speeds and wind energy potential over the study region are further quantified. It is shown that wind speed and power would significantly be reduced in the high CO_2 climate scenario offshore of the mid-Atlantic and northeast U.S., with the speed falling to one quarter of its original value. 相似文献
920.