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81.
Understanding the factors that influence voluntary conservation is critical for developing effective residential water conservation policy. Previous work drawing on Schwartz’s Norm Activation Model (NAM) has been useful to understand some of these factors. However, one’s relationship with the broader community impacted by consumptive decisions has often been overlooked. Similarly, scholars have emphasized the importance of contextual factors not captured in the NAM. In this study we hypothesize and test an augmented NAM that incorporates community attachment, along with contextual variables (sociodemographic and household infrastructure), to understand the factors that lead to the development of moral obligations to conserve water and their relationship with residential outdoor water use. Results indicate personal norms, defined as a moral obligation to conserve water, are negatively related to outdoor water use, and that community attachment is a predictor of personal norms. Contextual factors are found to have an influence on outdoor water use. 相似文献
82.
Nwosu Ebuka C. Brauer Achim Kaiser Jérôme Horn Fabian Wagner Dirk Liebner Susanne 《Journal of Paleolimnology》2021,66(3):279-296
Journal of Paleolimnology - Since the beginning of the Anthropocene, lacustrine biodiversity has been influenced by climate change and human activities. These factors advance the spread of harmful... 相似文献
83.
Natural Resources Research - Quantifying the change in field expected ultimate recovery across time is an old and complex topic fraught with ambiguity and misinterpretation. In this paper, changes... 相似文献
84.
Geospatial susceptibility mapping of earthquake-induced landslides in Nuweiba area,Gulf of Aqaba,Egypt 总被引:1,自引:0,他引:1
Earthquake induced landslides are one of the most severe geo-environmental hazards that cause enormous damage to infrastructure, property, and loss of life in Nuweiba area. This study developed a model for mapping the earthquake-induced landslide susceptibility in Nuweiba area in Egypt with considerations of geological, geomorphological, topographical, and seismological factors. An integrated approach of remote sensing and GIS technologies were applied for that target. Several data sources including Terra SAR-X and SPOT 5 satellite imagery, topographic maps, field data, and other geospatial resources were used to model landslide susceptibility. These data were used specifically to produce important thematic layers contributing to landslide occurrences in the region. A rating scheme was developed to assign ranks for the thematic layers and weights for their classes based on their contribution in landslide susceptibility. The ranks and weights were defined based on the knowledge from field survey and authors experiences related to the study area. The landslide susceptibility map delineates the hazard zones to three relative classes of susceptibility: high, moderate, and low. Therefore, the current approach provides a way to assess landslide hazards and serves for geo-hazard planning and prediction in Nuweiba area. 相似文献
85.
The so-called Hundsheim rhinoceros, Stephanorhinus hundsheimensis, was a very common faunal element of the Early to early Middle Pleistocene period in the western Palaearctic. In this study, individuals from two different central European populations of the Hundsheim rhinoceros were analysed in order to determine whether their local dietary signals could reflect differing food availability between the two populations, and whether such information could provide a better understanding of the ecological role of S. hundsheimensis within corresponding faunal assemblages, and of its principal subsistence strategy in the western Palaearctic. The mesowear traits observed in the studied S. hundsheimensis populations have been interpreted as representing biome-specific signals, indicating grassland vegetation at the site of Süßenborn, and dense to open forests at Voigtstedt (both localities in Germany). The analyses performed on the fossil rhino material demonstrate the most pronounced dietary variability ever established for a single herbivorous ungulate species by mesowear studies. This variability ranges from an attrition dominated grazing regime, to a one of predominantly browsing, and characterises S. hundsheimensis as the most ecologically tolerant rhinoceros of the Palaearctic Plio-Pleistocene. Although such dietary flexibility proved an effective enough subsistence strategy over a period of 600–900 ka (1.4/1.2–0.6/0.5 Myr) in the western Palaearctic, the situation changed dramatically after 0.6 Myr BP, when the new species of rhinoceroses, Stephanorhinus hemitoechus and Stephanorhinus kirchbergensis, appeared and started to compete for both the grass and the browse. For the generalist S. hundsheimensis, this bilateral interference was detrimental to its success in all of its habitats. The successful competition of specialised forms of rhinoceroses, which might have originated as a result of the development of 100 ka periodicity in the global climatic record, is proposed as the main reason for the extinction of S. hundsheimensis during the early Middle Pleistocene. 相似文献
86.
Amino acids, neutral sugars and amino sugars were analyzed to investigate the chemical composition and diagenetic processing of suspended particulate organic matter (POM, > 100 nm), high-molecular-weight dissolved organic matter (HMW DOM, 1–100 nm) and low-molecular-weight dissolved organic matter (LMW DOM, < 1 nm) at the time-series stations near Bermuda (BATS) and Hawaii (HOT). Differences between BATS and HOT were principally related to location-specific biogeochemical processes and water mass ventilation ages. Concentrations of amino acids, neutral sugar and amino sugars in unfiltered seawater sharply declined with depth at both stations, indicating an upper ocean source and rapid turnover of these components. The size distribution of organic matter was heavily skewed to smaller molecular sizes. Depth comparisons showed that larger size classes of organic matter were more efficiently removed than smaller size classes. Carbon-normalized yields of amino acids, neutral sugars and amino sugars decreased rapidly with depth and molecular size. Together these biochemicals accounted for 55% of organic carbon in surface POM but only 2% of the organic carbon in LMW DOM in deep water. Chemical compositions showed distinct differences between organic matter size classes indicating the extent of diagenetic processing increased with decreasing molecular size. These findings are consistent with the size-reactivity continuum model for organic matter in which bioreactivity decreases with decreasing molecular size and diagenetic processes lead to the formation of smaller components that are resistant to biodegradation. The data also provided evidence for a size-composition continuum. Carbon-normalized yields of amino acids, neutral sugars and amino sugars were sensitive indicators of diagenetic alterations. Diagenetic indicators based on amino acid compositions revealed distinct patterns for the North Pacific and Sargasso Sea possibly indicating the influence of varying sources or diagenetic processing. 相似文献
87.
The brittle failure behavior of an over-consolidated clay shale (Opalinus Clay) in undrained rapid triaxial compression was
studied. The confining stress levels were chosen to simulate the range of confining stresses relevant for underground excavations
at the Mont Terri Underground Research Laboratory, and to investigate the transition from axial splitting failure to macroscopic
shear failure. Micro-crack initiation was observed throughout the confining stress range utilized in this study at a differential
stress of 2.1 MPa on average, which indicates that friction was not mobilized at this stage of brittle failure. The rupture
stress was dependent on confinement indicating friction mobilization during the brittle failure process. With increasing confinement
net volumetric strain decreased suggesting that dilation was suppressed, which is possibly related to a change in the failure
mode. At confining stress levels ≤0.5 MPa specimen rupture was associated with axial splitting. With increasing confinement,
transition to a macroscopic shearing mode was observed. Multi-stage triaxial tests consistently showed lower strengths than
single-stage tests, demonstrating cumulative damage in the specimens. Both the Mohr–Coulomb and Hoek–Brown failure criteria
could not satisfactorily fit the data over the entire confining stress range. A bi-linear or S-shaped failure criterion was
found to satisfactorily fit the test data over the entire confinement range studied. 相似文献
88.
The Arman field in western Kazakhstan is estimated to hold recoverable reserves of 3.65 million metric tons of oil and 74
million cubic meters of gas. The field began production in 1994 as a joint venture between Oryx Energy, MangistauMunaiGas,
and the State Holding Company Zharkyn, and currently is operated by Royal Dutch Shell in a 50:50 joint venture with Lukoil.
The geology, crude composition, and production history of Arman is outlined, followed by a review of the field development,
contract structure, and operating and capital expenditures. An assessment of field profitability concludes the discussion.
相似文献
Mark J. KaiserEmail: |
89.
A. A. Konovalenko A. A. Stanislavsky E. P. Abranin V. V. Dorovsky V. N. Mel’nik M. L. Kaiser A. Lecacheux H. O. Rucker 《Solar physics》2007,245(2):345-354
Here we report a radio burst in absorption at 9?–?30 MHz observed with the UTR-2 telescope. This event occurred on 19 August 2003 about 11:16?–?11:26 UT, against solar type IV/II emission background. It is the first event where absorption was observed below 30 MHz. The absorption region, comparable with the solar radius size, traveled a long distance into the upper corona from the Sun. We show that the burst minimum corresponds to the almost full absorption of the solar radio emission up to a background level of the quiescent Sun. This supports the interpretation of the phenomenon as an absorption. The result is examined independently with the Nançay Decameter Array measurements and the Wind WAVES instrument records. 相似文献
90.
Jack A. C. Kaiser 《地球物理与天体物理流体动力学》2013,107(1):159-186
AbstractIn the high-amplitude wave regime, at each point in the axial plane, the temperature has a maximum, a minimum, and a time (or longitudinally) averaged value due to the propagation of the regular waves. The axial-plane profile of each of these three temperature fields was measured for 53 different combinations of ω, Δr w T and n. A few sample profiles are displayed.Correlations of several internal thermal parameters (especially Ro g,t ) with the externally imposed parameters, are given along with the spatial variation of the thermal fields. Ro g,t is always less than the value which would occur if the symmetrical regime existed, while the variation of Sz g,t with the imposed parameters is about the same as for the symmetrical regime. The parametric variation of the wave amplitude is the only quantity dependent on n. Based on the parametric variation of the fields, the wave regime diagram can be subdivided into several different regions : a quasi-conductive, a conductive-convective zone, and a region at large rotation rates and temperature differences characterized by Ro g,t = Ro g,w 2, Sz o,l = Ro g,w , and ΔT′ = (z′)0.6.The Ro g, l fields are compared to existing theory and some of the experimental stability diagrams of Fultz et al. (1964) are reconstructed using the internal instead of the externally imposed Rossby number. The transition from three to four waves via a “minor wave” is illustrated. 相似文献