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31.
Jeffrey J. Cook 《社会与自然资源》2014,27(12):1257-1270
The preproposal stage of the rulemaking process is notoriously understudied, but enormously important in determining regulatory outputs. Recently, Rinfret (2011c) analyzed the U.S. Fish and Wildlife Service (USFWS) rulemaking process and developed a frame analysis model to interpret stakeholder influence during the preproposal stage. Rinfret argues that stakeholders use three frames to influence agency rulemaking, including an expertise, a fiscal feasibility, and an information frame. This article tests this model to determine whether it is applicable to other federal agencies such as the National Park Service (NPS). Through an analysis of stakeholder framing within the 2012 NPS Yellowstone Winter Use Rule, this research confirms that Rinfret's model is indeed applicable to the NPS process. Therefore, this research suggests that this theoretical model examining stakeholder influence is applicable to other public land agencies, and arguably can be applied across the bureaucracy. 相似文献
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Linearized water wave theory is used to show that a submerged long circular cylinder suitably constrained by springs and dampers to make small harmonic oscillations, can be extremely efficient in absorbing the energy in an incident regular wave whose crests are parallel to the axis of the cylinder. Experimental results are described which confirm the theory for small amplitude waves and which suggest that the device can still be fairly efficient in waves of moderate amplitude. 相似文献
34.
Patrizia Köpfli Lorenz M. Grämiger Jeffrey R. Moore Christof Vockenhuber Susan Ivy-Ochs 《Swiss Journal of Geoscience》2018,111(1-2):205-219
Landslide deposits dam Lake Oeschinen (Oeschinensee), located above Kandersteg, Switzerland. However, past confusion differentiating deposits of multiple landslide events has confounded efforts to quantify the volume, age, and failure dynamics of the Oeschinensee rock avalanche. Here we combine field and remote mapping, topographic reconstruction, cosmogenic surface exposure dating, and numerical runout modeling to quantify salient parameters of the event. Differences in boulder lithology and deposit morphology reveal that the landslide body damming Oeschinensee consists of debris from both an older rock avalanche, possibly Kandertal, as well as the Oeschinensee rock avalanche. We distinguish a source volume for the Oeschinensee event of 37 Mm3, resulting in an estimated deposit volume of 46 Mm3, smaller than previous estimates that included portions of the Kandertal mass. Runout modeling revealed peak and average rock avalanche velocities of 65 and 45 m/s, respectively, and support a single-event failure scenario. 36Cl surface exposure dating of deposited boulders indicates a mean age for the rock avalanche of 2.3 ± 0.2 kyr. This age coincides with the timing of a paleo-seismic event identified from lacustrine sediments in Swiss lakes, suggesting an earthquake trigger. Our results help clarify the hazard and geomorphic effects of rare, large rock avalanches in alpine settings. 相似文献
35.
Charles W. Finkl Jr. Syed M. Khalil Jeffrey L. Andrews 《Marine Georesources & Geotechnology》2013,31(2):155-173
Erosion of sandy beaches is a worldwide problem that elicits innovative geoengineer‐ing techniques to reduce adverse impacts of shoreline retreat. Beach replenishment has emerged as the “soft”; shore‐stabilization technique of choice for mitigating beach erosion. This method of shore protection involves the addition of sand to the littoral sediment budget for sacrificial purposes. Because inland sand sources are often uneconomical or impractical to use, and known nearshore sources are limited, finding adequate quantities of suitable sand on the inner continental shelf is often vital to beach replenishment projects. The technical studies of survey and materials analysis that identify and delineate usable sand sources are sometimes almost as expensive as small‐project dredging, pumping, and placing the sand on the beach as fill. Inadequate quantity or substandard quality of shelf sand, as well as often‐prohibitive overhead expenses, thus compel shoreline managers to seek suitable sand sources offshore. In the study area off the central‐west coast of Florida, offshore potential borrow areas (PBAs) were identified on the basis of studies conducted in reconnoitory and detailed phases. Sophisticated state‐of‐the‐art equipment used in this investigation provided more detailed subbottom mapping information than is normally obtained with conventional seismic equipment. An example of sand exploration studies was incorporated in a 215‐km2 survey of offshore areas by conducting bathymetric surveys and subbottom seismic profiling, collecting jet probes, grab samples, and vibrocores, and analyzing sediment grading in subsamples from vibrocores. These combined analyses indicated that at least 8.8 ×106 m3 of sand is available in potential borrow areas from 7.0 to 12 km offshore in water depths of 8.0 to 11.5 m. In the PBAs, mean grain size of sand falls into the range 0.13–0.53 mm, sorting averages 0.65–1.31ø, and the overall silt content varies from 3.9–8.5%. High silt contents (13–19%) mapped in some areas make these sedimentary deposits unsuitable as fill for artificial beach renourishment. 相似文献
36.
Akihiro Hachikubo Oleg Khlystov Masato Kida Hirotoshi Sakagami Hirotsugu Minami Satoshi Yamashita Nobuo Takahashi Hitoshi Shoji Gennadiy Kalmychkov Jeffrey Poort 《Geo-Marine Letters》2012,32(5-6):419-426
This study reports measurements of the Raman spectra of Lake Baikal gas hydrates and estimations of the hydration number of methane-rich samples. The hydration number of gas hydrates retrieved from the southern Baikal Basin (crystallographic structure I) was approx. 6.1. Consistent with previous results, the Raman spectra of gas hydrates retrieved from the Kukuy K-2 mud volcano in the central Baikal Basin indicated the existence of crystallographic structures I and II. Measurements of the dissociation heat of Lake Baikal gas hydrates by calorimetry (from the decomposition of gas hydrates to gas and water), employing the hydration number, revealed values of 53.7–55.5?kJ?mol–1 for the southern basin samples (structure I), and of 54.3–55.5?kJ?mol–1 for the structure I hydrates and 62.8–64.2?kJ?mol–1 for the structure II hydrates from the Kukuy K-2 mud volcano. 相似文献
37.
Jeffrey Poort Oleg M. Khlystov Lieven Naudts Albert D. Duchkov Hitoshi Shoji Shin’ya Nishio Marc De Batist Akihiro Hachikubo Masato Kida Hirotsugu Minami Andrey Y. Manakov Marina V. Kulikova Alexey A. Krylov 《Geo-Marine Letters》2012,32(5-6):407-417
Thermal measurements and hydrate mapping in the vicinity of the K-2 mud volcano in Lake Baikal have revealed a particular type of association of thermal anomalies (29–121?mW?m–2) near hydrate-forming layers. Detailed coring within K-2 showed that hydrates are restricted to two distinct zones at sub-bottom depths exceeding 70–300?cm. Temperature data from stations with hydrate recovery and degassing features all display low thermal gradients. Otherwise, the thermal gradients within the mud volcano are generally increased. These findings imply a more complicated thermal regime than often assumed for mud volcanoes, with important roles for both fluids and hydrates. The coexistence of neighbouring low and high thermal anomalies is interpreted to result from discharging and recharging fluid activity, rather than hydrate thermodynamics. It is suggested that hydrates play a key role in controlling the fluid circulation pattern at an early stage. At a later stage, the inflow of undersaturated lake water would favour the dissolution of structure I hydrates and the formation of structure II hydrates, the latter having been observed on top of structure I hydrates in the K-2 mud volcano. 相似文献
38.
Jeffrey E. Moore Bryan P. Wallace Rebecca L. Lewison Ramúnas Žydelis Tara M. Cox Larry B. Crowder 《Marine Policy》2009
This paper reviews the available information (observer programs, estimates, statutes, regulations) for bycatch of marine mammals, sea turtles, and seabirds in fisheries of the United States. Goals of the review were to evaluate the state of knowledge of bycatch and the role of existing protective legislation in shaping bycatch management for different taxa. Pressing issues are identified, as well as knowledge gaps and policy limitations that hinder multi-species bycatch reduction. The USA has made important progress toward reducing bycatch in its fisheries, but the efficacy of its management has been limited somewhat by a focus on taxon- and fishery-specific regulation and the lack of consistent mandate across taxa for taking a cumulative perspective on bycatch. Applying consistent criteria across taxa for setting bycatch limits (e.g., extending the approach used for marine mammals to sea turtles and seabirds) would be the first step in a multi-species approach to bycatch reduction. A population-based multi-species multi-gear approach to bycatch would help identify priority areas where resources are needed most and can be used most effectively. 相似文献
39.
Akihiro Hachikubo Oleg Khlystov Alexey Krylov Hirotoshi Sakagami Hirotsugu Minami Yutaka Nunokawa Satoshi Yamashita Nobuo Takahashi Hitoshi Shoji Shin’ya Nishio Masato Kida Takao Ebinuma Gennadiy Kalmychkov Jeffrey Poort 《Geo-Marine Letters》2010,30(3-4):321-329
We investigated the molecular composition (methane, ethane, and propane) and stable isotope composition (methane and ethane) of hydrate-bound gas in sediments of Lake Baikal. Hydrate-bearing sediment cores were retrieved from eight gas seep sites, located in the southern and central Baikal basins. Empirical classification of the methane stable isotopes (δ13C and δD) for all the seep sites indicated the dominant microbial origin of methane via methyl-type fermentation; however, a mixture of thermogenic and microbial gases resulted in relatively high methane δ13C signatures at two sites where ethane δ13C indicated a typical thermogenic origin. At one of the sites in the southern Baikal basin, we found gas hydrates of enclathrated microbial ethane in which 13C and deuterium were both highly depleted (mean δ13C and δD of –61.6‰ V-PDB and –285.4‰ V-SMOW, respectively). To the best of our knowledge, this is the first report of C2 δ13C–δD classification for hydrate-bound gas in either freshwater or marine environments. 相似文献
40.
Damage costs from hurricanes have increased dramatically as hurricane strikes, populations, and property values have increased along the U.S. southeastern and Gulf Coast states. Federal expenditures in hurricane affected areas and coastal property insurance costs have increased as well. We discuss current public and private sector actions that impact damage costs and consider ways to mitigate future damage costs and government financial exposure. Encouraging adaptive and avoidance measures through market signals and government policies, and protecting areas such as wetlands which mitigate storm damage will help limit damage from hurricanes. 相似文献