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141.
We present the Northern HIPASS (H  i Parkes All-Sky Survey) Optical/Infrared Catalogue (NOIRCAT), an optical/near-infrared (NIR) counterpart to the Northern HIPASS Catalogue (NHICAT). Of the 1002 sources in NHICAT, 655 (66 per cent) have optical counterparts with matching optical velocities. A further 85 (8 per cent) sources have optical counterparts with matching velocities from previous radio emission-line surveys. We find a correlation between the gas and stellar content of the NOIRCAT sources. Our H  i -selected sample of isolated galaxies also presents a wider range in NIR colours than previous optically selected studies of regular, isolated galaxies. All H  i detections in optically unobscured fields could be matched with either a NASA/IPAC Extragalactic Database optical counterpart, or a galaxy visible in Second Palomar Observatory Sky Survey or Digitized Sky Survey images. However, as over 200 of these matched galaxies have no velocity information, further follow-up observations are needed to confirm the matches, and hence confirm or deny the existence of dark galaxies in this data set.  相似文献   
142.
Book reviews     
GRIFFITH TAYLOR: Antarctic scientist and pioneer geographer (Carleton Library Series No. 145) by M. Sanderson. 15 x 23 cm, xi and 218 pages. Carleton University Press: Ottawa 1988 (ISBN 0 88629 068 6) $C24.95 (hard); (ISBN 0 88629 068 X) $C14.95 (soft) plus postage.

LAND, WATER AND PEOPLE: Geographical essays in Australian resource management edited by R. L. Heathcote and J. A. Mabbutt. 14 x 21 cm, xiii and 266 pages. Allen & Unwin: Sydney 1988 (ISBN 0 04 303008 4) $A24.95 (soft).

ENVIRONMENTAL GEOGRAPHY: Book One by J. Paine, H. McLean and G. Mayhew. 19 x 25 cm, 389 pages. Macmillan: Melbourne 1988 (ISBN 0 333 43073 5) $A28.95 (soft).

Climate Impact Assessment Program (1975) Impacts of climate change on the biosphere, Monograph No. 5, US Department of Transportation, Washington DC.

SMALL‐SCALE AGRICULTURE edited by J. Hirst, J. Overton, B. Allen and Y. Byron. 18 x 25 cm, xii and 210 pages. Commonwealth Geographical Bureau and Department of Human Geography, Australian National University: Canberra 1988 (ISBN 0 7316 3609 0) $A 10.00 (soft).

THE BRITTLE RIM: Finance, Business and the Pacific Region by M. T. Daly and M. I. Logan. 15 × 23 cm, 263 pages, Penguin Books: Ring‐wood 1989 (ISBN 0 14 012095 5) $A24.99 (soft)

THE END OF ORGANISED CAPITALISM by S. Lash and J. Urry. 15 x 23cm, 383 pages. Polity Press: Cambridge 1987 (ISBN 07456 00697) $A34.95 (soft).

THE POLITICS OF DEVELOPMENT: An Introduction to Global Issues by J. L. Seitz. 15 x 23 cm, xiii and 194 pages. Basil Blackwell: New York 1988 (ISBN 0 631 15801 4) $A27.95 (soft).

DEVELOPING WITH FOREIGN INVESTMENT edited by V. Cable and B. Persaud. 16 x 24 cm, viii and 327 pages. Croom Helm: London 1987 (ISBN 0 7099 4825 5) $A87.95 (hard).

PLANNING SYDNEY'S FUTURE by P. Spearritt and C. DeMarco, 21 x 27 cm, and 150 pages. Allen & Unwin: Sydney 1988 (ISBN 0 04 324014 3) $A17.95 (soft).

THE RICHEST LODE: Broken Hill 1888–1988 by R. J. Solomon. 22 x 28 cm, 424 pages. Hale & Iremonger: Sydney 1988 (ISBN 0 86806 333 9).

CONTEMPORARY ISSUES IN DEVELOPMENT (North Australia: Progress and Prospects, Volume 1) edited by D. Wade‐Marshall and P. Loveday. xiii and 310 pages. North Australia Research Unit, Australian National University: Darwin 1988 (ISBN 07315 0335 X).

NEW CALEDONIA OR KANAKY? The Political History of a French Colony (Pacific Research Monograph No. 16) by J. Connell. National Centre for Development Studies, Australian National University: Canberra 1987 (ISBN 0 7315 05123).

DISEASE ECOLOGY by Andrew Learmonth. 15 x 23 cm, 456 pages. Basil Blackwell: Oxford 1988 (ISBN 0 631 15799 9) $A46.00 (soft).

QUALITATIVE METHODS IN HUMAN GEOGRAPHY edited by J. Eyles and D. M. Smith. 15 x 23 cm, xiii and 272 pages. Polity Press: Cambridge 1988 (ISBN 0 7456 0371 8) $A34.95 (soft).

GEOGRAPHICAL SYSTEMS AND SYSTEMS OF GEOGRAPHY: Essays in Honour of William Warntz edited by W. J. Coffey. 14 x 21 cm, 211 pages. Department of Geography, University of Western Ontario: London, Ontario 1988 (ISBN 0 7714 09747) $C30.00 (soft).  相似文献   

143.
The Nebo–Babel Ni–Cu–platinum-group element (PGE) sulphide deposit in the West Musgrave Block, Western Australia, is the largest nickel sulphide discovery in the last 10 years. The deposit is hosted within a concentrically zoned, olivine-free, tube-like (chonolithic), gabbronorite intrusion associated with the, approximately, 1,078-Ma Giles Complex-layered intrusions in the Warakurna large igneous province. Emplaced into sulphide-free amphibolite facies orthogneiss, the fault-offset Nebo–Babel chonolith extends for 5 km and has a cross-section of 1 × 0.5 km. Igneous mineralogy, fabrics, and textures are well preserved. The lithostratigraphy includes variably textured leucogabbronorites (VLGN) that form an outer shell around mineralised gabbronorite (MGN), with barren gabbronorite (BGN) and oxide–apatite gabbronorite (OAGN) in the middle and lower parts of the chonolith. Mineral and whole-rock geochemistry indicate that the units become progressively evolved in the order: VLGN, MGN, BGN, and OAGN, and that incompatible trace-element concentrations increase downwards within the MGN and BGN. The mineralisation, which is confined to the early, more primitive units (VLGN and MGN), occurs as massive sulphide breccias and stringers and as disseminated gabbronorite-hosted sulphides. The massive sulphides were emplaced late in the intrusive sequence, have different PGE chemistry and Cu tenor to the disseminated sulphides, and have undergone sulphide fractionation. The distribution of disseminated sulphides, which are primary magmatic in origin, is related to chonolith geometry and magma flow regimes, rather than to gravitational settling. Sulfur-bearing country rocks are absent in the Nebo–Babel deposit area, and thus, local crustal S addition was unlikely to have been the major mechanism in achieving sulphide immiscibility. The Nebo–Babel intrusion is part of an originally continuous magma chonolith with multiple and related magma pulses. The parental magma was medium- to low-K tholeiite with 8–9 wt% MgO. The initial magma pulse (VLGN), the most primitive and sulphide saturated, was probably emplaced along a linear weakness in the country rock. After crystallisation of VLGN, marginally more fractionated, sulphide-saturated magma was injected through the thermally insulated core of the conduit, forming the MGN. Successive pulse(s) of more fractionated magma (BGN) were emplaced in the core of the intrusion. After magma flow ceased, closed system crystal fractionation produced consistent mineral and chemical fractionation trends within BGN and OAGN. After crystallisation, the intrusion was overturned and then offset by the Jameson Fault resulting in the apparent ‘reverse’ chemical and mineral trends in Nebo–Babel.  相似文献   
144.
Sarah Neal  Sue Walters 《Geoforum》2007,38(2):252-263
Using qualitative data from a research project investigating contemporary rural identities in England this paper examines the apparently contradictory discursive claims that are made on rural spaces. It looks in particular at the ways in which these are narrated - through the notions of rural space as a site of safety, orderliness and community on the one hand and as a site of freedom, anti-order and non-regulation on the other. While the former is a familiar, entrenched and critiqued representation of rurality, the latter narrative has a more marginal and ambivalent place in the dominant rural imaginary. Drawing on Foucault’s concepts of panopticism and heterotopia the paper demonstrates the ways in which the rural is a highly labile concept and emphasises its continual ‘unfinishedness’. However, alongside this, the paper suggests that the tensions and contradictions of the orderly and anti-orderly discourses are underpinned by a particular coherency that is driven by senses of community, belonging and self-regulation. While these do not resolve the contradictions of the discursive claims the potency of such drivers are sufficient to produce a particular inclusive spatiality which is able to accommodate and incorporate the different discursive positions and the practices that are associated with each.  相似文献   
145.
The Western Alps’ active tectonics is characterized by ongoing widespread extension in the highest parts of the belt and transpressive/compressive tectonics along its borders. We examine these contrasting tectonic regimes using a multidisciplinary approach including seismotectonics, numerical modeling, GPS, morphotectonics, fieldwork, and brittle deformation analysis. Extension appears to be the dominant process in the present-day tectonic activity in the Western Alps, affecting its internal areas all along the arc. Shortening, in contrast, is limited to small areas located along at the outer borders of the chain. Strike-slip is observed throughout the Alpine realm and in the foreland. The stress-orientation pattern is radial for σ3 in the inner, extensional zones, and for σ1 in the outer, transcurrent/tranpressional ones. Extensional areas can be correlated with the parts of the belt with the thickest crust. Quantification of seismic strain in tectonically homogeneous areas shows that only 10–20% of the geodesy-documented deformation can be explained by the Alpine seismicity. We propose that, Alpine active tectonics are ruled by isostasy/buoyancy forces rather than the ongoing shortening along the Alpine Europe/Adria collision zone. This interpretation is corroborated by numerical modeling. The Neogene extensional structures in the Alps formed under increasingly brittle conditions. A synthesis of paleostress tensors for the internal parts of the West-Alpine Arc documents major orogen-parallel extension with a continuous change in σ3 directions from ENE–WSW in the Simplon area, to N–S in the Vanoise area and to NNW–SSE in the Briançon area. Minor orogen-perpendicular extension increases from N to S. This second signal correlates with the present-day geodynamics as revealed by focal-plane mechanisms analysis. The orogen-parallel extension could be related to the opening of the Ligurian Sea during the Early-Middle Miocene and to compression/rotation of the Adriatic indenter inducing lateral extrusion.  相似文献   
146.
147.
148.
The occurrence of red desert soil profiles developed on Nubian Sandstone in the Libyan Sahara is discussed. From an examination of profile morphology in the field and the position of the soils at 970 m on an old land surface, it would be possible to regard them as desert paleosols formed under a previous humid climatic phase during the Quaternary. However, an investigation of the mineralogy of the soils and the underlying parent rocks strongly suggests that the properties of the soils are largely dependent on the parent material. Both have identical patterns of kaolinite content, haematite as the main ferric oxide, and similar proportions of quartz silt and coarse quartz sand. Therefore, the use of kaolinite and ferric oxides in interpreting past soil-forming climates in arid regions needs to be carried out with caution, for in the present case such an interpretation would be unreliable.  相似文献   
149.
150.
Oyster Condition Index (CI) was partitioned, using a moving average filter, into seasonal cycles and long-term trends in the James, York, and Rappahannock rivers for the period 1970–1983. Seasonal cyclic fluctuations in CI could be explained partially by changes in salinity and number of days within various temperature regimes. Long-term trends in the James River show a steady increase in CI over the study period, while a concurrent decline was noted in the Rappahannock River. Superimposed on these trends is a 4 to 5 yr cycle that is in synchrony with river discharge (salinity). In the York River, CI peaked in 1975–1976 at all stations. Measured environmental parameters do not sufficiently explain the trends. We speculate that the differences in the Rappahannock and James rivers may be due to a decline in bottom oxygen as a result of gravitational circulation differences.  相似文献   
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