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81.
为查明色达—松潘断块地热资源赋存状态及热源来源,以四川黑水县内3处温泉(热水塘、上达古、卡龙沟)为研究对象,采集温泉水样进行水化学分析和同位素测试,研究地热水的补给来源和热储温度。研究结果显示,热水塘温泉的地下水化学类型为HCO3-Na型,上达古温泉和卡龙沟温泉的地下水化学类型为HCO3-Ca型,补给水源主要为大气降水,补给高程分别为5 121 m、3 890 m、3 921 m。结合矿物饱和指数,采用SiO2地热温标计算3处温泉的热储温度,分别为119.036 ℃、49.034 ℃、30.215 ℃。综合分析认为研究区地下热水的成因主要为大气降水经高山补给区入渗至储集层,吸取地下深部向上传导的热量和放射性元素衰变释放的热量,并与围岩发生水-岩作用形成地下热水,在断裂发育部位热水沿断裂带向上运移,最后在地表出露形成温泉。 相似文献
82.
83.
Phyllosoma larvae collected to date in Japanese and Taiwanese waters have been classified into two genera (Linuparus, Panulirus) of the Palinuridae, four genera (Ibacus, Parribacus, Scyllarides, Scyllarus) of the Scyllaridae, and one genus (Palinurellus) of the Synaxidae. However, phyllosoma larvae of three Scyllarus species (S. bicuspidatus, S. cultrifer, S. kitanoviriosus) are absolutely dominant among the larvae collected in the waters. Scyllarus larvae are abundant in coastal waters while those of Panulirus are often collected in offshore/oceanic waters. Based on previous and ongoing studies dealing with spatial distributions
of phyllosoma larvae in Japanese and Taiwanese waters, it appears that phyllosoma and nisto larvae of the Scyllarus are retained within coastal waters north of the Kuroshio Current. On the other hand, the life history of the Panulirus (particularly P. japonicus) may be completed within the Kuroshio Subgyre: their phyllosoma larvae may be flushed out from coastal waters into the Kuroshio,
then transported through the Counter Current south of the Kuroshio into the water east of Ryukyu Archipelago and Taiwan where
they attain the subfinal/final phyllosoma or puerulus stages, once again entering the Kuroshio and dispersing into coastal
waters.
This revised version was published online in July 2006 with corrections to the Cover Date.
An erratum to this article is available at . 相似文献
84.
Decentralisation reforms and political conditions in the Philippines present an ideal environment for forest management by recognising the land entitlements of upland and indigenous communities and promoting the involvement of local government units. By assessing whether current conditions – policies, institutions, and programmes – are conducive to effective decentralisation, this study examines the present state of decentralisation in the forestry sector of the Philippines. By analysing case studies conducted in Nueva Vizcaya Province, it also attempts to answer a broader question: when is decentralisation a success and when is it a failure? A number of uncertainties are revealed, along with various issues that hamper decentralisation, and that are interrelated and reinforce one another in much the same way as they have done over the past decade. The study highlights the need for caution when increasing the involvement of government at different levels, as it affects the pace of decentralisation reforms. It also shows that a mix of site-specific interventions and community endeavours that focus on securing local livelihoods has led to some success. This is a strategy that helps decentralisation reforms. 相似文献
85.
86.
Shinya Kouketsu Hitoshi Kaneko Takeshi Okunishi Kosei Sasaoka Sachihiko Itoh Ryuichiro Inoue Hiromichi Ueno 《Journal of Oceanography》2016,72(3):439-451
We investigated the relationship between chlorophyll a (Chl-a) concentrations estimated from satellite observations and the activity of eddies in the Kuroshio Extension region. High (low) area-averaged Chl-a concentrations were frequently observed in the core of cyclonic (anticyclonic) eddies. Such relationships between Chl-a concentrations and eddy cores were not frequently observed in the southern part of the recirculation gyre, and advection of background meridional gradient of Chl-a by eddy-edge currents accounted for Chl-a spatial variability. Decadal-scale changes of Chl-a concentrations around the Kuroshio Extension were strongly affected by eddy activity and transport but not by large-scale near-surface isopycnal heaving. We also found that decadal changes of nutrient concentrations near the main stream could affect Chl-a concentrations in the southern part of the recirculation gyre via southward transport of eddies and mean flow. 相似文献
87.
It has been proved in the authors' latest paper that the effective location of active control devices for building vibration caused by periodic excitation acting on intermediate story is the adjacent three floors to the vibration source. However, in terms of the Discrete‐Optimizing control method, the control forces are on‐line calculated step‐by‐step and time‐delay must exist. The degradation of control effect caused by time‐delay can not be avoided. In this paper, QN control method is proposed in order to resolve this practical problem. Since the external excitations which the building structure would experience are supposed to be periodic to some degree, Quasi‐Newton method is applied into the close‐loop Linear–Quadratic optimal control method and the new control method is called the ‘QN control method’. In this new control method, instead of solving the Riccati equation, the feedback gain matrix is determined by optimizing the quadratic performance index of the structure with the Quasi‐Newton method, one of the most commonly used minimization of functions. The new control law can easily be implemented for time‐delay problems, the degradation can be greatly improved with compensated feedback gain matrix. As a result, the QN control method is proved to be an efficient method to determine the feedback gain matrix. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
88.
The fifth Japaniese X-ray astronomy satellite, Astro-E, following Hakucho, Tenma, Ginga, and ASCA is scheduled for launch in the year 2000 by the Institute of Space and Astronautical Science (ISAS) with an M-V rocket. The satellite will be put into an approximately circular orbit with an altitude of ∽550 km and an inclination of ∽31°. There will be three experiments on board Astro-E: an X-ray micro-calorimeter array, four X-ray CCDs and a hard X-ray detector. All three experiments combined, Astro-E will become a spectrometer facility covering a wide energy band from 0.5 keV to 600 keV. 相似文献
89.
D. W. Fox W. H. G. Lewin A. Fabian K. Iwasawa R. Terlevich H. U. Zimmermann B. Aschenbach K. Weiler S. Van Dyk R. Chevalier R. Rutledge H. Inoue S. Uno 《Monthly notices of the Royal Astronomical Society》2000,319(4):1154-1158
We report on multi-epoch X-ray observations of the Type IIn (narrow emission line) Supernova (SN) 1995N with the ROSAT and ASCA satellites. The 1998 January ASCA X-ray spectrum is well fitted by a thermal bremsstrahlung or power-law model. The X-ray light curve shows evidence for significant flux evolution between 1996 August and 1998 January: the count rate from the source decreased by 30 per cent between our 1996 August and 1997 August ROSAT observations, and the X-ray luminosity most likely increased by a factor of ∼2 between our 1997 August ROSAT and 1998 January ASCA observations, although evolution of the spectral shape over this interval is not ruled out. The high X-ray luminosity, places SN 1995N in a small group of Type IIn supernovae with strong circumstellar interaction, and the evolving X-ray luminosity suggests that the circumstellar medium is distributed inhomogeneously. 相似文献
90.
通过岩石学、同位素年代学、变形变质特征的研究及区域对比,认为凤太泥盆纪盆地东缘(黄柏原一带)原划泥盆纪地层应为新太古代-古元古代变质结晶基底,变质达角闪岩相,其可能是佛坪穹隆构造向西北延伸,进一步证明了泥盆纪时西部凤太盆地和东部山(阳)柞(水)镇(安)盆地是两个独立盆地,中间被佛坪穹隆隔挡。该项成果对研究南秦岭地壳演化和指导凤太地区的地质找矿意义重大。 相似文献