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931.
北黄海冷水团环流结构探讨──潮混合锋对环流结构的影响 总被引:10,自引:4,他引:10
简述北黄海冷水团环流结构研究现状,指出已有研究成果中的主要问题,然后用一个诊断模型给出了冷水团环流结构,得到冷水团环向主要存在于海洋上层接近冷水团边界处,径向运动也主要存在于断面两端,上层为离岸流,下层为向岸流;冷水团中心的上升流极为微弱,且仅存在于海洋上层,温跃层下的冷水团中心区域的流动极为微弱,几乎为“死水”一般,上述环流结构对冷水团中心部分的温、盐度长期保持不变及跃层底部溶解氧最大值的形成和 相似文献
932.
采用1987年5-6月中日合作黄东海海域综合调查溶解氧资料,参考有关文献,讨论调查海域溶解氧分布特征及与水团的对应关系。分析结果表明,各水团中溶解氧含量的差异与各水团温盐特性及生物地球化学过程不同有关。通过分析还发现溶解氧对鉴别次表层以深各水团,特别对东海次表层水及黑潮次表层以深各水团,是一个重要的指标。 相似文献
933.
夏季北黄海冷水团多年变化特征分析 总被引:7,自引:0,他引:7
本文根据横贯北黄海冷水团的大连—成山角断面的42年观测资料,采用“相似系数”方法分析了北黄海冷水团的分布范围、低温中心位置、厚度、相对体积、温、盐特征等的多年变化特征。根据诸特征的标准离差,将这42年北黄海冷水团划分为强、弱和平年三种情况 相似文献
934.
The paper presents a theoretical and an experimental investigation into the free vibration of a large ring-stiffened prolate dome in air and under external water pressure.The theoretical investigation was via the finite element method where a solid fluid mesh with an isoparametric cross-section was used to model the water surrounding the dome, and a truncated conical shell and ring stiffener were used to model the structure. Good agreement was found between theory and experiment. Both the theory and the experiment found that as the external water pressure was increased the resonant frequencies decreased. 相似文献
935.
变性水团软划分的一种FUZZY模式 总被引:1,自引:0,他引:1
在已知研究海区水团核心的前提下,考虑到各种指标对标识水团的不同贡献,提出了一种水团软划分的FUZZY模式。利用1987年5—6月黄东海的温、盐和溶解氧实测资料进行计算,与已有成果作了对比,结果令人满意。 相似文献
936.
Using our data from special observation in the source area of the Taiwan Warm Current from 19S2 to 1985) and historical data, the authors conducted studies to clarify the temperature and salinity characteristics, variability, and origin of the Taiwan Warm Current Water, and its influence on the expanding direction of the Changjiang Diluted Water.The main results of these studies are briefly given below. (1) The Taiwan Warm Current Water can be divided into two parts:the Surface Water of the Taiwan Warm Current and the Deep Water of the Taiwan Warm Current; the former is formed due to the mixing of the Kuroshio Surface Water flowing northward along the east coast of Taiwan with the Taiwan Strait Water; the latter completed originates from Kuroshio Subsurface Water to the east of Taiwan. It is characterized by lower temperature and higher salinity in summer and the characteristics of temperature and salinity are more stable. The maximum seasonal variational range and maximum secular variational range of t 相似文献
937.
Osamu Shida Tomonori Hamatsu Akira Nishimura Akifumi Suzaki Jun Yamamoto Kazushi Miyashita Yasunori Sakurai 《Deep Sea Research Part II: Topical Studies in Oceanography》2007,54(23-26):2822
The Japanese Pacific walleye pollock (Theragra chalcogramma) stock is the largest stock of this species in Japanese waters. It is a key component of the Oyashio ecosystem. In southern Hokkaido waters, these fish spawn mainly during January and February near the mouth of Funka Bay (FB), and most eggs and larvae are transported into FB. During midsummer juvenile pollock migrate along the southern coast of Hokkaido to a nursery ground on the continental shelf off eastern Hokkaido (Doto area). However, some eggs and larvae are transported southward to the Tohoku region (TR). Transport depends largely on the Oyashio, which generally flows southward along the eastern coasts of Hokkaido and Tohoku. Thus, this stock has two different recruitment routes: FB–Doto and FB–TR. In the 1980s, when the southward flow of the Oyashio was strong, the number of age-2 pollock estimated from a virtual population analysis (VPA) indicated that recruitment to the entire stock remained at a medium level. In the 1990s, when the Oyashio weakened, strong year-classes occurred in 1991, 1994, and 1995, but not in the latter half of the 1990s. Juvenile catches in the TR by commercial fisheries, which can be taken as indices of recruitment level via FB–TR, were high during the 1980s and decreased in the 1990s. Although there was no significant difference in the average number of recruits between the 1980s and the 1990s as estimated from a VPA, the recruitment patterns differed between the two decades. Here, we propose that recruitment routes of this stock shifted in response to environmental changes. 相似文献
938.
在安德拉水位计的实际应用中,除由压力测量引起的水位测量误差外,在水位数据的计算中,也存在着误差因素。本文分析了这些因素的误差分量,并粗略地估算了它们的大小;由此提出了参与水位值计算的几个主要订正参数的选值方法。 相似文献
939.
Tomoharu?SenjyuEmail author Yutaka?Isoda Takafumi?Aramaki Shigeyoshi?Otosaka Shinzo?Fujio Daigo?Yanagimoto Takashi?Suzuki Kenshi?Kuma Kosuke?Mori 《Journal of Oceanography》2005,61(6):1047-1058
Hydrographic observations have revealed detailed structure of the Bottom Water in the Japan Sea. The Yamato Basin Bottom Water
(YBBW) exhibits higher temperatures and lower dissolved oxygen concentrations than those found in the Japan Basin Bottom Water
(JBBW). Both Bottom Waters meet around the boundary region between the Yamato and the Japan Basins, forming a clear benthic
front. The structure of the benthic front suggests an estuary-like water exchange between both Basins, with the inflow from
the Japan Basin passing under the outflow from the Yamato Basin. It is inferred from the property distributions that the JBBW
flowing into the Yamato Basin is entrained by the cyclonic circulation in the basin, and modified to become the YBBW. Vertical
diffusion and thermal balance in the YBBW are examined using a box model. The results show that the effect of geothermal heating
has about 70% of the magnitude of the vertical thermal diffusion and both terms cancel the advection term of the cold JBBW
from the Japan Basin. The box model also estimates the turnover time and vertical diffusivity for the YBBW as 9.1 years and
3.4 × 10−3 m2s− 1, respectively. 相似文献
940.