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981.
This paper assesses how far community led rural visions accord with the current thrust of rural planning policy delivery in
the UK. Adapting conventional visioning methods, qualitative techniques were used on eight different communities across urban,
exurban and rural Wales to elicit views relating to the kind of local countryside(s) that were desired. The results show that
the communities’ visions reflect an emerging consensus around local countryside priorities: multifunctionality, integration,
wider countryside protection, development based on need, and local distinctiveness according with the thrust of current planning
policy at national and local levels. However, there is a clear dichotomy between this and the reality of what communities
actually experienced in developments affecting their countryside. Here, universal criticism was encountered over the type,
pace and scale of development, the lack of rural specificity and the failure to take account of local community needs and
priorities. It is hypothesized that tensions between national and local politics and stakeholder power relations are playing
a crucial role in distorting the delivery of town and country planning. It is recommended that rural policy delivery must
become more “joined up” and rural proofed at national and local levels concomitant with a change in the operational culture
of agencies at the forefront of rural delivery. Essentially, effective engagement of top down approaches synergising with
bottom up community led ideas is long overdue. 相似文献
982.
First- and second-order adaptation to natural hazards and extreme events in the context of climate change 总被引:2,自引:1,他引:2
Jörn Birkmann 《Natural Hazards》2011,58(2):811-840
This paper deals with coping and adaptation processes to natural hazards and (potential) climate change impacts. Selected
response measures to natural hazards are critically reviewed with respect to the actual and potential consequences that these
measures might imply for additional adaptation needs and changes within social-ecological systems. In this context, the author
introduces the concept of first- and second-order adaptation processes in order to underline the cascade process that adaptation
implies, the potentials for failure, and the limits of adaptation. Important aspects of first- and second-order adaptation
processes as well as the issue of the limits of adaptation are illustrated based on observations and empirical work conducted
in Vietnam. In its final part, the paper discusses the findings in light of selected theoretical approaches that might help
to understand how stabilization and destabilization processes are influenced or even triggered by adaptation measures. 相似文献
983.
Monometamorphic metasediments of Paleozoic or Mesozoic age constituting Schneeberg and Radenthein Complex experienced coherent deformation and metamorphism during Late Cretaceous times. Both complexes are part of the Eoalpine high-pressure wedge that formed an intracontinental suture and occur between the polymetamorphosed Ötztal–Bundschuh nappe system on top and the Texel–Millstatt Complex below. During Eoalpine orogeny Schneeberg and Radenthein Complexes were south-dipping and they experienced a common tectonometamorphic history from ca. 115 Ma onwards until unroofing of the Tauern Window in Miocene times. This evolution is subdivided into four distinct tectonometamorphic phases. Deformation stage D1 is characterized by WNW-directed shearing at high temperature conditions (550–600°C) and related to the initial exhumation of the high-pressure wedge. D2 and D3 are largely coaxial and evolved during high- to medium-temperature conditions (ca. 450 to ≥550°C). These stages are related to advanced exhumation and associated with large-scale folding of the high-pressure wedge including the Ötztal-Bundschuh nappe system above and the Texel–Millstatt Complex below. For the area west of the Tauern Window, F2/F3 fold interference results in the formation of large-scale sheath-folds in the frontal part of the nappe stack (formerly called “Schlingentektonik” by previous authors). Earlier thrusts were reactivated during Late Cretaceous normal faulting at the base of the Ötztal–Bundschuh nappe system and its cover. Deformation stage D4 is of Oligo-Miocene age and accounted for tilting of individual basement blocks along large-scale strike-slip shear zones. This tilting phase resulted from indentation of the Southern Alps accompanied by the formation of the Tauern Window. 相似文献
984.
We have calculated the compressional, vibrational, and thermodynamic properties of Ni3S2 heazlewoodite and the high-pressure orthorhombic phase (with Cmcm symmetry) using the generalized gradient approximation
to the density functional theory in conjunction with the quasi-harmonic approximation. The predicted Raman frequencies of
heazlewoodite are in good agreement with room-temperature measurements. The calculated thermodynamic properties of heazlewoodite
at room conditions agree very well with experiments, but at high temperatures (especially above 500 K) the heat capacity data
from experiments are significantly larger than the quasi-harmonic results, indicating that heazlewoodite is anharmonic. On
the other hand, the obtained vibrational density of states of the orthorhombic phase at 20 GPa reveals a group of low-frequency
vibrational modes which are absent in heazlewoodite. These low-frequency modes contribute substantially to thermal expansivity,
heat capacity, entropy, and Grüneisen parameter of the orthorhombic phase. The calculated phase boundary between heazlewoodite
and the orthorhombic phase is consistent with high-pressure experiments; the predicted transition pressure is 17.9 GPa at
300 K with a negative Clapeyron slope of −8.5 MPa/K. 相似文献
985.
Sebastien Fleuret 《GeoJournal》2011,76(2):177-189
New organizations of care and social service delivery (especially the development of coordination and networks) are leading
to the definition new spaces. This article is based on examples of restructuring of health care systems in France and in Quebec.
Both are moving towards more integration of delivery of care. In Quebec, 95 territories were created with a leading structure:
the center for health and social services. This structure is responsible for bringing all the providers of services into a
network and for giving to the population the guarantee of continuity and quality of care. It results in a new geography of
health at the local scale. In France, continuity and quality of care are also used as arguments to justify changes in the
organization of the system. 相似文献
986.
Paolo Budetta 《Natural Hazards》2011,56(1):233-250
This paper deals with a finite element stability analysis performed on a sea-cliff affected by a deep notch. The cliff is
about 200 m long with height ranging between 8 and 19 m. The notch at the cliff base is about 1 m above sea level, nearly
stretching along the entire cliff toe. Detailed geo-structural and geo-mechanical surveys were performed in situ, and rock
samples were tested in laboratory. The relevant physical and mechanical properties were used for determining rock mass strength
parameters. A finite element approach was implemented using a two-dimensional elasto-plastic finite-element stress analysis
program. The stability analysis shows that the notch causes increasing shear strains spreading from the notch end towards
the top cliff. Decreasing strength reduction factors affect the cliff as the notch reaches increased depth into the rock mass,
and when its depth is about 2 m the analysis results do not converge. At this stage, an uninterrupted shear plane develops
along which a roughly prismatic rock block can slide and then topple. 相似文献
987.
Destructive near-fault strong ground motion from the 2016 Kumamoto prefecture,Japan, M7.3 earthquake
Takashi Furumura 《Landslides》2016,13(6):1519-1524
The sequence of the 2016 Kumamoto, Japan, earthquake, which included an initial M6.5 foreshock on April 14, followed by a larger M7.3 mainshock on April 16, and subsequently occurred high aftershock activity, caused significant damage in Kumamoto and neighboring regions. The near-field strong motion record by strong motion network (K-NET and KiK-net) and the intensity meter network demonstrated clearly the characteristics of the strong ground motion developed by the shallow (H = 12 km), inland earthquake comprising short-time duration (<15–20 s) but large (>1G) ground accelerations. The velocity response spectra of the near-fault motion at Mashiki and Nishihara showed large levels (>300–550 cm/s) in the short-period range (T = 1–2 s), several times larger than that of the near-field record of the destructive 1995 Kobe earthquake (M7.3) and that of the 2004 Mid-Niigata earthquake (M6.8). This period corresponds to the collapse vulnerability of Japanese wooden-frame houses, and is the major cause of severe damage during the Kumamoto earthquake. The response spectra also showed extremely large levels (>240–340 cm/s) in the long-period (T > 3 s) band, which is potentially disastrous for high-rise buildings, large oil storage tanks, etc. to have longer resonant period. Such long-period motion was, for the most parts, developed by the static displacement of the fault movement rather than by the seismic waves radiating from the source fault. Thus, the extreme near-fault long-period motion was hazardous only close to the fault but it attenuated very rapidly away from the fault. 相似文献
988.
Sigismond A. Wilson 《GeoJournal》2011,76(3):191-212
Although the Kimberley Process Certificate Scheme has considerably reduced the flow of conflict diamonds from 4% to less than
1%, other forms of illicit diamonds are estimated at 20% of global production. While scholars and policy makers have given
considerable attention to illicit mining and smuggling (with some success), illicit exploitation still hinders revenue generation
that is needed for economic growth and development in Sub-Saharan African (SSA) countries heavily reliant on alluvial minerals.
Based on surveys of 240 households in four diamondiferous chiefdoms in Kono District in Sierra Leone, key informant interviews,
focus groups and secondary data, and drawing from the actor-oriented approach and Le Billon (Fuelling war: natural resources
and armed conflict. London, International Institute for Strategic Studies, 2005) conceptualization of the political geography of the resource, this paper examines the problem of illicit diamond exploitation
in post-conflict Sierra Leone. It investigates: (1) the causes of illicit diamond mining and smuggling; (2) the spatial and
temporal aspects of illicit mining and smuggling, and (3) possible solutions to illicit diamond exploitation. The paper argues
that the ineffectiveness of national mining laws/policies has created conditions that are exploited by local and international
actors in the diamond industry. This is further exacerbated by the political geography of the resource. Study findings reveal
that while better mining regulation could reduce illicit exploitation, bringing buyers closers to miners and offering them
better prices for rough diamonds will minimize smuggling and thus increase government’s mineral revenue base. 相似文献
989.
Impact of Berm Breaching on Hyperbenthic Macroinvertebrate Communities in Intermittently Closed Estuaries 总被引:1,自引:0,他引:1
Adrian W. T. Lill Gerard P. Closs Marc Schallenberg Candida Savage 《Estuaries and Coasts》2012,35(1):155-168
Berm breaching of intermittently closed estuaries, either naturally or due to management practices, results in a physicochemical
disturbance due to the flushing of water, material and biota into the ocean and the subsequent tidal influx. In 2007 and 2008
comparative and controlled studies were employed in three New Zealand estuaries: Sawmill Creek (46°04′ S 170°12′ E), Otokia
Creek (45°57′ S 179°20′ E) and Kaikorai Lagoon (45°56′ S 170°23′ E), to investigate the impact of berm breaching on the hyperbenthic
macroinvertebrate community in intermittently closed estuaries. Significant changes in community structure occurred in both
the weekly comparative and the controlled studies (ANOSIM P < 0.01). Furthermore, the catch per unit effort of both total
and key invertebrate taxa significantly increased after breaching (ANOVA P < 0.01). However, substantial numbers of individuals were expelled into the ocean (5,800 individuals, 20-min sample) while
new taxa immigrated into the estuaries. Along with migration-related changes to community structure, berm breaches also resulted
in the loss of ∼80% of inundated habitat and the concentration of existing populations. Consequently, the management of intermittent
estuary connections to the ocean has implications for the ecology of individual, managed estuaries and also for regional coastal
populations of epibenthic invertebrates. 相似文献
990.
The morphosedimentary evolution of a sector of the southern Espinhaco range (northern Minas Gerais State, Brazil) and its
regional neotectonic setting are presented herein. The studied site is a stream at base level flowing along the western border
of the range. Its identification was accomplished by using remote sensing techniques including the analysis of 3D slope models
generated with shuttle radar topography mission images. The main geomorphological features of the identified site were surveyed
in a 1:500 scale. In addition, seven stratigraphic logs are described. A regional geologic compilation and facies diagrams
were used as a basis for the integration of the geomorphological and stratigraphic data, which produced some conclusions about
the recent tectonic reactivations at the eastern border of Sao Francisco Craton. The results point to a local eastward tilting
of the Espinhaco range. This fact is in accordance with previous findings in neighboring areas and results in the asymmetric
evolution of the fluvial valley, as well as the regional relief. 相似文献