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61.
62.
Australian higher education has experienced substantial change since the early 1980s, with a transition to mass higher education, closer alignment to national political objectives, increasing Federal Government control, a growing emphasis on ‘quality’ and ‘value for money’, and organisational restructuring with manifestations ranging from the creation of the Unified National System to the merger or closure of individual departments. At the same time, evolving conceptions of learning and new patterns of demand, with growing emphasis on lifelong learning and flexible access to education, pose new challenges for educators. Now, the policies of the new Federal Coalition Government are likely to engender further change, with growing differentiation of universities a probable outcome. Information technology has so far played a relatively peripheral role in teaching and learning in higher education, but important changes there, including rapid shifts in the relationship between cost and computing power, and the explosive emergence of the World Wide Web, are now providing the basis on which information technology can become increasingly central to teaching and learning. Higher education is close to the limits of incremental adjustment to pressures for change and it seems likely that it will experience major restructuring, with its eventual reconstruction around the capabilities of information technology. Geography has already been much affected by restructuring pressures, including above‐average growth in teaching loads and threats to its disciplinary identity because of internal reorganisation of many universities. Despite a tradition of innovative, high‐quality teaching, geography has not generally been a leader in the development and application of information technology. Nevertheless, a case study of an experimental use of the World Wide Web provides an example of directions that teaching and learning in the discipline might take.  相似文献   
63.
Fort Morgan Peninsula is an attached portion of a dynamic barrier complex in the northern Gulf of Mexico and is a large tourist area that brings in a significant amount of revenue for Alabama. Many of the hotels and tourist attractions depend on the groundwater as their water supply. The over-withdrawal of groundwater and saltwater intrustion will have a negative impact on the ecology, tourism and economy if groundwater resources are not properly monitored and managed. In this study a calibrated groundwater flow model was used to analyze the sustainability of groundwater resources at Fort Morgan Peninsula. Detailed flow budgets were prepared to check the various components of inflow and outflow under different water use and climatic conditions. The results indicated the locations where groundwater was over-pumped and subjected to saltwater intrusion, or will be subjected to saltwater intrusion under a range of projected water use and climatic conditions.  相似文献   
64.
AUSTRALIA: A GEOGRAPHY. Volume 1: The Natural Environment edited by D. N. Jeans. 18 × 25 cm, viii and 347 pages. Sydney University Press: Sydney 1986 (ISBN 0 424 00114 4) $A55.00 (hard); (ISBN 0 424 00124 1) $A32.50 (soft).

Western Australia. Departments of Education and Lands and Survey (1979) Western Australia: an atlas of human endeavour, 1829–1979, Government Printer, Perth.

ATLAS OF SOUTH AUSTRALIA edited by T. Griffin and M. McCaskill. 28 × 40 cm, xiv and 134 pages. South Australian Government Printing Division and Wakefield Press on behalf of the South Australian Jubilee 150 Board: Adelaide 1986 (ISBN 0 7243 46880) $A55.00 (hard).

URBAN AUSTRALIA: Planning Issues and Policies edited by S. Hamnett and R. Bunker. 16 × 24 cm, 192 pages. Nelson Wadsworth: Melbourne 1987 (ISBN 0 17 007166 9) $A29.95 (hard).

AUSTRALIAN URBAN DEVELOPMENT AND INTERNATIONAL FINANCE CAPITAL (Working Paper No. 31) by M. T. Daly. 21 × 30 cm, viii and 39 pages. Transnational Corporations Research Project, University of Sydney 1985 (ISBN 0 908470 66 5) $A5.00 (soft).

TRANSNATIONAL CAPITAL AND URBANIZATION IN JAPAN (Research Monograph No. 25) by M. Douglass. 21 × 30 cm, viii and 42 pages. Transnational Corporations Research Project, University of Sydney 1987 (ISBN 0 908470 74 6) $A10.00 (soft).

MELBOURNE WESTERN REGION: Industrial Sites Atlas by Melbourne Western Region Joint Working Group. 45 × 32 cm, 40 pages. Melbourne Western Region Joint Working Group: Melbourne 1984 $A20.00 (soft).

MINE INFRASTRUCTURE AND ECONOMIC DEVELOPMENT IN NORTHERN AUSTRALIA by C. O'Faircheallaigh. 18 × 25 cm, vi and 87 pages. North Australia Research Unit, Australian National University: Darwin 1987 (ISBN 0 7315 0043 1) $A10.00 (soft).

AUSTRALIA'S CHANGING POPULATION: Trends and Implications by G. Hugo. 16 × 24 cm, x and 354 pages. Oxford University Press: Melbourne 1986 (ISBN 0 19 554680 6) $A40.00 (hard).

WOMEN OVER SIXTY: A Study of the Housing, Economic and Social Circumstances of Older Women (Publication No. 130) by L. Coleman and S. Watson. 17 × 24 cm, v and 89 pages. Australian Institute of Urban Studies: Canberra 1987 (ISBN 0 86419 112 X).

THE MANNING VALLEY: Landscape and Settlement 1824–1900 by W. K. Birrell. 21 × 29 cm, xvi and 280 pages. Jacaranda: Milton, Qld, 1987 (ISBN 0 7016 2170 2) $A29.95 (hard).

ISSUES IN THE MANAGEMENT OF AUSTRALIA'S WATER RESOURCES by J. J. Pigram. 15 × 23 cm, xvi and 331 pages. Longman Cheshire: Melbourne 1986 (ISBN 0 582 71139 8) $A24.95 (soft).

PROSPECTS FOR HARDWOOD FORESTS (Monograph No. 19) edited by J. Dargavel and G. Sheldon. 16 × 23 cm, xv and 334 pages. Centre for Resource and Environmental Studies, Australian National University, Canberra 1987 (ISBN 0 86740 226 1) $A19.95 plus $A5.00 post and packing (soft).

FOREST SOILS AND NUTRIENT CYCLES by P. M. Attiwill and G. W. Leeper. 15 × 22 cm, x and 202 pages. Melbourne University Press: Melbourne 1987 (ISBN 0 522 84315 8) $A29.90 (hard).

AUSTRALIAN SOILS: The Human Impact edited by J. S. Russell and R. F. Isbell. 26 × 18 cm, xi and 522 pages. University of Queensland Press: St Lucia 1986 (ISBN 0 7022 1968 1) $A50.00 (hard).

THE AUSTRALIAN SUMMER MONSOON, TELECONNECTIONS, AND FLOODING IN THE LAKE EYRE BASIN (South Australian Geographical Papers No. 2) by R. J. Allen. 18 × 25 cm, 47 pages. Royal Geographical Society of Australasia (South Australian Branch): Adelaide 1985 (ISBN 0 909112 09 6).  相似文献   

65.
Book reviews     
VANISHING RAIN FORESTS: the ecological transition of Malaysia (Oxford Monographs on Biogeography No.5) by S.R. Aiken and C.H. Leigh. 19 × 25 cm, xvii and 194 pages. Clarendon Press, Oxford 1992. (ISBN 0 19 854242 9) $130.00 (hard)

ECOGEOGRAPHY AND RURAL MANAGEMENT: a contribution to the International Geosphere‐Biosphere Programme by J. Tricart and C. Kiewiet de Jonge. 267 pages. Longman/Wiley, New York 1992. (ISBN 0 582 06273 X) $51.00.

THE NEW SOCIAL ECONOMY: reworking the division of labor by A. Sayer and R. Walker. 15 × 23 cm, viii and 306 pages. Blackwell, Cambridge MA, 1992. (ISBN 1 55786 280 X) $49.95 (soft)

TROPICAL AFRICAN DEVELOPMENT: geographical perspectives edited by M.B. Gleave. 366 pages. Longmans/Wiley, New York 1992. (ISBN 0 582 30147 5)

MINING AND INDIGENOUS PEOPLES IN AUSTRALASIA edited by J. Connell and R. Howitt. 13 × 21 cm, × and 205 pages. Sydney University Press, Sydney 1991. (ISBN 0 424 00177 2) $22.95 (soft)

GOVERNMENT SCHOOLS OF NEW SOUTH 1848 TO 1993 (Fourth edition) edited by M. McPherson. 21 × 30 cm, 242 pp. NSW Department of School Education, Sydney, 1993. (ISBN 0 7310 0288 1). $22.00 (soft)(inc. postage).  相似文献   

66.
The synchronous observations of strong electric fields and large-scale undulations observed on December 12, 2004, in the evening sector of the diffuse auroral zone 0900-1000 UT (~1700-1800 MLT) have been analyzed. The appearance of strong northward electric field at ~0900 UT was almost simultaneously registered at Tixie Bay ionospheric station (71.6° N, 128.9° E, L =, 5.6) and on the DMSP F15 satellite. At 0910-1000 UT, the all-sky TV camera at Tixie Bay and the DMSP satellites (F13, F14, and F15) registered eight undulations propagating westward at a velocity of 0.7—0.8 km/s. The undulation parameters registered during the TV observations agree with the satellite measurements. The distinctive feature of the analyzed event consists in that an intense electric field and undulations were localized within the diffuse zone in the region of increased precipitation of keV electrons. A comparison of the ground-based and satellite measurements made it possible to draw the conclusion on the necessary conditions for formation of diffuse undulations.  相似文献   
67.
Rangia cuneata is an upper estuarine clam common in the coastal regions of the Gulf of Mexico. Limited data exist regarding oxygen isotope fractionation and microstructural increment periodicity in this species. As these clams were recently identified as an invasive species in other regions, such data may be useful for environmental management purposes. Additionally, the shell of this clam is common in archeological middens, and thus may serve as a paleoenvironmental proxy. In order to assess these aspects of the species’ natural history, samples were collected from the upper Mobile Bay, Alabama, USA. A stable oxygen isotope profile was generated from one of these valves, and compared to growth increments seen in thin section. Time-series water temperature data from near the collection site were used to construct idealized models of oxygen isotope variation, assuming equilibrium fractionation, constant shell growth, and stable water δ18O values. Comparison of the modeled and measured data suggest the shell was precipitated in, or near oxygen isotope equilibrium with ambient water, and that the microstructural increments in the shell were precipitated in response to tidal cycles.  相似文献   
68.
Analysis of Urban Atmosphere Plume Concentration Fluctuations   总被引:1,自引:1,他引:0  
Concentration variability in the fast-response tracer dataset for continuous, near-surface, point source releases in the urban core from the Joint Urban 2003 field study is analyzed. Concentration variability for conditionally and unconditionally sampled time series is characterized by probability densities, concentration fluctuation intensity, skewness, and kurtosis. Significant day-night differences in plume dispersion are observed. Relative to daytime, nighttime plumes were more likely to have reduced concentration fluctuation intensities, higher normalized surface concentrations, suppressed vertical mixing, and a greater prevalence of Gaussian-like distributions rather than log-normal or mixed mode distributions. This was in spite of the similar stability and turbulence conditions in the urban core for day and night. The potential roles of flow meander and thermal stability in explaining these differences are examined. Probability densities of concentration are found to be a strong function of fluctuation intensity. There are few differences in probability densities between day and night when classified by fluctuation intensity. There are no appreciable differences between conditional and unconditional probability densities and only small differences between conditional and unconditional sampling statistics relative to the larger differences usually observed in more homogeneous settings. Fluctuation intensity, skewness, and kurtosis are higher for the daytime experiments, and closer to the source, but show little difference between conditional and unconditional results over most of their range of values. The log-normal distribution provides a better overall fit to a broader range of the dataset than the exponential or clipped-normal distributions.  相似文献   
69.
The subduction and export of subantarctic mode water (SAMW) as part of the overturning circulation play an important role in global heat, freshwater, carbon and nutrient budgets. Here, the spatial distribution and export of SAMW is investigated using Argo profiles and a climatology. SAMW is identified by a dynamical tracer: a minimum in potential vorticity. We have found that SAMW consists of several modes with distinct properties in each oceanic basin. This conflicts with the previous view of SAMW as a continuous water mass that gradually cools and freshens to the east. The circulation paths of SAMW were determined using (modified) Montgomery streamlines on the density surfaces corresponding with potential vorticity minima. The distribution of the potential vorticity minima revealed “hotspots” where the different SAMW modes subduct north of the Subantarctic Front. The subducted SAMWs follow narrow export pathways into the subtropical gyres influenced by topography. The export of warmer, saltier modes in these “hotspots” contributes to the circumpolar evolution of mode water properties toward cooler, fresher and denser modes in the east.  相似文献   
70.
Coincident multi-instrument magnetospheric and ionospheric observations have made it possible to determine the position of the ionospheric footprint of the magnetospheric cusp and to monitor its evolution over time. The data used include charged particle and magnetic field measurements from the Earth-orbiting Viking and DMSP-F7 satellites, electric field measurements from Viking, interplanetary magnetic field and plasma data from IMP-8, and Sondrestrom incoherent scatter radar observations of the ionospheric plasma density, temperature, and convection. Viking detected cusp precipitation poleward of 75.5○ invariant latitude. The ionospheric response to the observed electron precipitation was simulated using an auroral model. It predicts enhanced plasma density and elevated electron temperature in the upper E- and F-regions. Sondrestrom radar observations are in agreement with the predictions. The radar detected a cusp signature on each of five consecutive antenna elevation scans covering 1.2 h local time. The cusp appeared to be about 2○ invariant latitude wide, and its ionospheric footprint shifted equatorward by nearly 2○ during this time, possibly influenced by an overall decrease in the IMF Bz component. The radar plasma drift data and the Viking magnetic and electric field data suggest that the cusp was associated with a continuous, rather than a patchy, merging between the IMF and the geomagnetic field.  相似文献   
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