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71.
Outdoor domestic water use is often targeted by demand management strategies. However, despite a rich empirical evidence base coming from primary studies, it is still unclear how factors that influence this type of demand interact and which are the most suitable to be addressed by water conservation programs. Based on 423 scientific contributions, we develop a research synthesis combining a variety of techniques to create a theoretical model of the relationships among factors most consistently observed in the literature. The findings uncover a great degree of complexity in terms of interactions between spatial-structural, social-structural, and cultural and psychological factors at different scales. For researchers, the methodology and the outcomes can be useful to better frame existing and future research within the literature on the topic. In practice, the adaptation of the theoretical model to local specificities can facilitate the design of more efficient and integrated demand management strategies.  相似文献   
72.
Albert Defant 《Ocean Dynamics》1952,5(5-6):231-245
Zusammenfassung Es wird ein Überblick über unsere derzeitigen Kenntnisse der internen Wellen im Ozean gegeben, wobei besonders jene mit Gezeitencharakter berücksichtigt werden. Die theoretischen Erörterungen sind möglichst kurz gehalten. Die Koppelung mit den Trägheitsschwingungen ausgedehnter Meeresgebiete erfährt eine eingehende Würdigung. Zum Schluß werden auch die Stabilitätsbedingungen interner Gezeitenwellen erörtert.
On internal waves, especially on those of tidal periods
Summary This is an outline of our present knowledge of internal waves in the ocean with special reference to internal waves of tidal periods. The theoretical aspect is dealt with as briefly as possible. The coupling with the phenomenon of osciallations of inertia in large ocean areas is discussed in detail. Finally, the stability conditions of internal tide waves are treated.

Sur des vagues internes, surtout sur celles ayant des périodes de marée
Résumé Voilà un aperçu de notre connaissance d'aujourd'hui des vagues internes dans l'océan, surtout de celles qui ont des périodes de marée. L'aspect théorique est brièvement traité. Le rapport avec les oscillations d'inertie en larges régions océaniques est précisé. Enfin, les conditions de stabilité des vagues internes de marée sont exposées.


Vortrag, gehalten im geophysikalischen Kolloquium der Universität Hamburg am 10. Dezember 1952.  相似文献   
73.
Zusammenfassung Die Bearbeitung von dynamischen Schnitten quer zu ozeanischen Küsten mit Windstau und Auftriebsphänomenen, insbesondere jener Schnitte, die das große Beobachtungsmaterial des Marine Life Research Program der Scripps Institution of Oceanography in La Jolla (California) geliefert hat, hat den inneren Mechanismus des Vorganges bei Windstau oder Auftrieb an ozeanischen Küsten klargelegt, so daß es nun möglich ist, die Zusammenhänge in einfachen schematischen Modellen theoretisch zu erfassen. In der vorliegenden Untersuchung wird das Modell eines freien Ozeans mit anschließendem Schelfmeer unter vereinfachenden Annahmen vollständig durchgerechnet. Der Vergleich eines zahlenmäßigen Beispiels mit den Verhältnissen vor der kalifornischen Küste ergibt eine gute Übereinstimmung. Dies läßt annehmen, daß im theoretischen Modell alle das Phänomen mitbestimmenden Faktoren richtig erfaßt worden sind.
Theoretical considerations on the phenomenon of wind effect (Windstau) and upwelling on oceanic coasts
Summary The elaboration of dynamic sections located at right angles to oceanic coasts with banking effects as well as upwelling phenomena, above all the working up of those profiles based on the comprehensive observation material obtained under the Marine Life Research Program by the Scripps Institution of Oceanography of La Jolla (California) has recently enabled the internal mechanism of the processes of the piling up or upwelling of water on oceanic coasts to be revealed; thus it is now possible to theoretically conceive the correlations with the aid of simple schematic patterns. In the present paper the model of an open ocean with an adjacent shelf sea is completely computed under certain simplifying assumptions. A numerical example is compared with the conditions existing off the coast of California and the correspondence is found to be good. This allows of the assumption that in the theoretical model all factors exerting an essential influence on the phenomenon under discussion have been properly taken into account.

Considérations théoriques des phénomènes de montée et de baisse de niveau sur les littoraux
Résumé En se servant des coupes dynamiques orientéesperpendiculairement à la direction générale des littoraux soumis aux phénomènes de montée et de baisse de niveau sous la pression du vent de mer et celle du vent de terre, et surtout en élaborant les nombreuses observations faites sous le Marine Life Research Program de la Scripps Institution of Oceanography à La Jolla (Californie) on est récemment arrivé à éclaircir le mécanisme interne de la montée et de la baisse de niveau sur les littoraux. Il est donc possible de saisir d'une manière théorique les corrélations à l'aide de simples modèles schématiques. On a introduit des suppositions simplifiantes dans le travail suivant et on a complètement calculé le modèle d'un océan ouvert se reliant à une zone adjacente de la marge continentale. L'exemple numérique donné est en bon accord avec les conditions devant la côte de la Californie. On peut donc supposer que tous les éléments qui influencent essentiellement ce phénomène ont été proprement introduits dans le modèle théorique.
  相似文献   
74.
The aim of this article is to introduce the Beach Crowding Index (BCI), a procedure to assess the social carrying capacity of vulnerable beaches. The study uses the people at one time (PAOT) approach and data gathered weekly throughout the bathing season regarding the number of beachgoers in 100 m2 cells of the beach to assess how many beachgoers it can comfortably hold. The procedure is based on fieldwork, interviews with beachgoers, and geographic information system (GIS) analysis and has been tested on four beaches in protected areas on the Spanish Mediterranean coast. On a scale from 0 to 4, minimum scores throughout the bathing season are 0.7 and maximum 3.7, although results showed wide variation between the beaches, the section of the beach, and the time of day. This study suggests that determining the location of beachgoers and collecting a long-term series of data is fundamental to assessing social carrying capacity and that the BCI procedure can be used for a large number of applications.  相似文献   
75.
Increases in biodiversity losses are a growing concern globally. In farm animals, related concerns about losses in genetic diversity have potentially increased with the emergence of breeding technologies that allow for faster genetic change in herds. Farmer and public acceptance of specific breeding practices can be influenced by a number of factors, including concerns about biodiversity and knowledge of biodiversity. The link between these factors and acceptance of new genetic technologies, if it exists, may help explain concerns about genetic technologies. This article examines the effect of attitudes and knowledge about biodiversity on the acceptance of genomic selection in livestock production using farmer and public survey data from Canada. Our results suggest that the link between biodiversity concerns and the acceptance of genomic selection is more robust for the public than for farmers. We also find that biodiversity knowledge and attitudes have opposite effects on acceptance of genomic selection.  相似文献   
76.
Concentrations of selected heavy metals (Cr, Cu, Ni, Pb and Zn) from surface sediments, suspended particulate matter and settling particles in the southern Barcelona continental margin were studied in order to evaluate the environmental impact of the anthropogenic metals discharged by the Llobregat River in this Mediterranean area. The temporal variation of heavy metals discharged by this river onto the continental shelf is clearly related to the river water flow. Part of the fine sediment and associated heavy metals transported by the Llobregat River during periods of low river flow accumulate on the river bed, and they are totally removed and discharged onto the Barcelona continental shelf during sporadic river water flow increases. Metals produce significant anomalies of chromium (×2.5), copper (×3.4) and zinc (×3.7) in the surface sediments of the Llobregat prodelta and tend to be transported along the continental shelf following the mean flow. Metals associated with the finest suspended flocs transferred to the slope are controlled by the shelf-slope density front and are transported along slope by the general geostrophic current, instead of accumulating and becoming concentrated in the slope bottom sediments. Settling particulate matter collected in sediment traps on the Barcelona continental slope offshore of the shelf-slope front shows low heavy metal concentrations except in a few sediment trap samples that are significantly metal-enriched in chromium (×4.5) and zinc (×6.8). This enrichment is associated with very short and sporadic river flow increases and is only recorded inside the Foix submarine canyon, which acts as a preferential conduit for the shelf-slope sediment transfer.  相似文献   
77.
The correct characterization of aquifer parameters is essential for water‐supply and water‐quality investigations. Slug tests are widely used for these purposes. While free software is available to interpret slug tests, some codes are not user‐friendly, or do not include a wide range of methods to interpret the results, or do not include automatic, inverse solutions to the test data. The private sector has also generated several good programs to interpret slug test data, but they are not free of charge. The computer program SlugIn 1.0 is available online for free download, and is demonstrated to aid in the analysis of slug tests to estimate hydraulic parameters. The program provides an easy‐to‐use Graphical User Interface. SlugIn 1.0 incorporates automated parameter estimation and facilitates the visualization of several interpretations of the same test. It incorporates solutions for confined and unconfined aquifers, partially penetrating wells, skin effects, shape factor, anisotropy, high hydraulic conductivity formations and the Mace test for large‐diameter wells. It is available in English and Spanish and can be downloaded from the web site of the Geological Survey of Spain. Two field examples are presented to illustrate how the software operates.  相似文献   
78.
A reliable estimation of sediment transport in gravel‐bed streams is important for various practical engineering and biological studies (e.g., channel stability design, bed degradation/aggradation, restoration of spawning habitat). In the present work, we report original laboratory experiments investigating the transport of gravel particles at low bed shear stresses. The laboratory tests were conducted under unsteady flow conditions inducing low bed shear stresses, with detailed monitoring of the bed topography using a laser scanner. Effects of bed surface arrangements were documented by testing loose and packed bed configurations. Effects of fine sediments were examined by testing beds with sand, artificial fine sand or cohesive silt infiltrated in the gravel matrix. Analysis of the experimental data revealed that the transport of gravel particles depends upon the bed arrangement, the bed material properties (e.g., size and shape, consolidation index, permeability) and the concentration of fine sediments within the surface layer of moving grains. This concentration is directly related to the distribution of fine particles within the gravel matrix (i.e., bottom‐up infiltration or bridging) and their transport mode (i.e., bedload or suspended load). Compared to loose beds, the mobility of gravel is reduced for packed beds and for beds clogged from the bottom up with cohesive fine sediments; in both cases, the bed shear stress for gravel entrainment increases by about 12%. On the other hand, the mobility of gravel increases significantly (bed shear stress for particle motion decreasing up to 40%) for beds clogged at the surface by non‐cohesive sand particles. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
79.
Kilometric-scale shoreline sand waves (KSSW) have been observed in the north-east flank of the Dungeness Cuspate Foreland (southeastern coast of the UK). They consist of two bumps separated by embayments with a 350–450-m spacing. We have analysed 36 shoreline surveys of 2-km length using the Discrete Fourier Transformation (DFT), from 2005 to 2016, and seven topographic surveys encompassing the intertidal zone, from 2010 to 2016. The data set shows two clear formation events. In order to test the role of high-angle waves on the KSSW formation, the 10-year wave series is propagated from the wave buoy located at 43 m depth up to a location in front of the undulations at 4 m depth using the SWAN wave model. The dominating SW waves arrive with a very high incidence angle (~ 80°) while the NE waves arrive almost shore normal. The ratio R, which measures the degree of dominance of high-angle waves with respect to low-angle waves, correlates well with the shoreline DFT magnitude values of the observed wavelength undulations. In particular, the highest R values coincide with the formation events. Finally, a linear stability model based on the one-line approximation is applied to the Dungeness profile and the 10-year propagated wave series. It predicts accurately the formation moments, with positive growth rates in the correct order of magnitude for wavelengths similar to the observed ones. All these results confirm that the shoreline undulations in Dungeness are self-organized and that the underlying formation mechanism is the high-angle wave instability. The two detected formation events provide a unique opportunity to validate the existing morphodynamic models that include such instability.  相似文献   
80.
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