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901.
902.
Guan Bingxian 《中国海洋湖沼学报》1986,4(3):239-255
Based on the current measurement data from the R/V Ryofu Maru of JMA in the equatorial area along 137°E (1972–83) and 155°E (1972–79) the structures of the zonal velocity of the Equatorial Undercurrent (EUC) and the North Equatorial Countercurrent (NECC) and their variations are systematically analyzed in detail. At 155°E, the current at the equator and 100–300 m depth was a typical eastward EUC, it intensified in 1973–75, i.e., in the non-El Niño period. While the corresponding current at 137°E was mostly westward, and the origin of the EUC shifted to north of the equator around 0.5–1.5°N owing to the influence of the New Guinea Coast. The EUC origin disappeared in early July, 1982. Comparing with the EUC disappearance at 159°W, the average speed of an eastward travelling wave would be~1.1m/s. The velocity core of the NECC at 137°E generally shifted northward in winter and southward in summer, and was stronger in summer and weaker in winter. The fluctuations of the NECC were closely related to those of the wind stress curl over the region 2–10°N, 160°E–150°W. 相似文献
903.
Guan Bingxian 《中国海洋湖沼学报》1990,8(2):167-176
The deep water (1000–3000 m) circulation in the area east of Taiwan and the Philippines has been little studied. Moriyasu
(1972) and Reid (1981) discussed the 3000 db surface (3000/1200 db) and 2000 db surface (2000/3500 db) circulations of the
Philippine Sea Basin, respectively. They both showed that there may be a northward current close to the western margin of
the Sea Basin. Recent analyses of two sets of deep sea hydrographic data yielded quite different results, i. e., at deep waters
in the area east of Taiwan and the Philippines southward countercurrents flow under the upper northward currents.
The possible causative mechanism of these southward deep countercurrents is the blocking effects of the submarine ridge east
of Suao and of the Ryukyu Islands Shelf on the northward flowing upper currents.
The above-mentioned preliminary deductions were wholely based on consideration of the relative geostrophic current and calculation,
though the reference surface (3500 db) was very deep. It is suggested that direct measurements of the deep currents in the
study area are needed to verify these results.
Contribution No. 1750 from the Institute of Oceanology, Academia Sinica. This paper was presented at the PRC/USA Symposium
on Western Pacific Air-Sea Interaction (Nov., 1988, Beijing). This project was supported by the National Natural Science Foundation
of China. 相似文献
904.
A note on circulation of the East China Sea 总被引:1,自引:0,他引:1
905.
To improve understanding of property measurements in heterogeneous media, an energy-based weighting function concept is developed. In (assumed) homogeneous media, the instrument spatial weighting function (ISWF) depends only on the energy dissipation distribution set up by the measurement procedure and it reduces to simply inverse sample volume (uniform weighting) for 1-D parallel flow case (ideal permeameter). For 1-D transient flow in homogeneous media, such as with slug tests, the ISWF varies with position and time, with 95% of the total weighting contained within 115 well radii, even late in the test. In the heterogeneous case, the determination of the ISWF is connected to the problem of determining an equivalent hydraulic conductivity (K), where the criterion for equivalence is based on equal energy dissipation rate rather than equal volume discharge. The discharge-based equivalent K (K(E)) and the energy-based equivalent K in heterogeneous media (K(eh)) are not equal in general, with K(eh) typically above the nodal arithmetic mean K. The possibly more fundamental problem is that as one makes K measurements in heterogeneous media at different locations or on different cores of heterogeneous materials, the ISWF will be heterogeneity dependent, implying that the averaging process resulting in the equivalent K value also varies with position. If the testing procedure is transient, then the averaging process varies with time. This suggests a fundamental ambiguity in the interpretation of hydraulic conductivity measurements in heterogeneous media that may impact how we approach modeling and prediction in a practical sense (Molz 2003). Further research is suggested. 相似文献
906.
Chee Kong Yap Ahmad Ismail Abdul Rahim Ismail Soon Guan Tan 《湿地科学》2006,4(4):247-252
The distribution and concentrations of Cd, Cu, Pb and Zn were determined in the gills and remaining soft tissues of Perna viridis collected from 12 geographical sites ( 10 from the west and 2 from the east coastal waters) of Peninsular Malaysia. All samples showed that the levels of Cd, Pb and Zn were generally higher in the gill than those in the remaining soft tissues. These results could be due to the fact that gills are the first organ of metal accumulation and larger surface area with mucus sheets in the organ. Since the mussel gill is a better accumulator of Cd, Pb and Zn of ambient seawater than remaining soft tissue, it is a potential indicator of ambient levels of dissolved metals in the ambient seawater. However, further validations based on laboratory conditions are needed. 相似文献
907.
液氮消冷雾微结构的演变分析 总被引:3,自引:0,他引:3
液氮已广泛用于外场的人工增雨和消雾,是“十五”人工影响天气攻关研究和推荐的催化剂之一;其优势在于价廉,对环境无污染,资源丰富,-8℃以上成冰率高于AgI。文章介绍用液氮在首都机场的消雾试验,讨论和分析了消雾前后雾微结构的演变。对地跨北京14个区县,持续48h,能见度最低时达20~30m的气团平流雾连续播撒液氮,35min后下风方4.8km的测立占出现冰雪晶,形状以柱状为主,平均浓度为0.35个/cm^3。冰雪晶的出现破坏了雾的胶性稳定性,能见度很快得以改善,水平能见度增加到300~600m。 相似文献
908.
909.
本文针对现行油田地面工程数字化与建库方案中存在的问题,提出对油田地面工程的设计和施工等阶段产生的数据与技术资料加以利用的新思路,以及一套全新、高效率、实用的油田地面工程数字化与建库的技术方案与作业流程,并制定了相应的数据收集与整理的技术要求.本文还结合新疆油田石西作业区地面建设工程数字化与建库工程的实践,利用GeoMedia Professional地理信息软件平台进行二次开发,实现了数据的自动化入库.从而解决了现行技术方案中的周期长、人力与物力资源浪费等问题. 相似文献
910.
日照是气象台站的基本观测项目之一。目前气象台站所使用的日照计多为暗筒式日照计,它是利用太阳光通过仪器上的小孔射入筒内,使涂有感光剂的日照纸上留有感光迹线来计算日照时数。因此,日照纸的涂药质量,直接关系到日照记录的准确性。 相似文献