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11.
An interdisciplinary approach involving analysis of plant macrofossils, pollen and soil micro morphology in combination with large-scale stripping of top soil, was applied in order to get a comprehensive understanding of pre-historic settlement, farming economy and land-use in Østfold, SE Norway. Investigations of 25 sites lead to two distinctive results: 1) A time-space perspective on usages of plants, and 2) Identification of agrarian activities in a relict field. Studies of these topics have hitherto been limited for this region. The results add fresh and essential knowledge to pre-historic times in Østfold and make a significant contribution to the understanding to these topics in neighbouring regions.  相似文献   
12.
This study presents the application of multi-element soil analyses (X-ray fluorescence spectroscopy and inductively coupled plasma optical emission spectroscopy of 1 M HCl extracts) to grid samples from 3 archaeological house plans embedded in sandy clays, clays and sands to assess effects of site lithology on geochemical signatures of human occupation.  相似文献   
13.

In comparison with the teaching of most other geography topics, where fieldwork can be conducted relatively easily and seminars can be based on some pre-existing knowledge and first-hand experience of the issues, the range of resources and approaches available to tutors teaching the geography of development is necessarily more limited. Tutors often have to rely more heavily on 'top-down' teaching and more passive learning approaches, such as using videos, slides and lectures. While students may gain a theoretical understanding of development concepts, issues and problems, they may be left without a deeper 'experience' of such material. This paper describes a practical workshop designed to communicate to students the idea of 'appropriate technology'. The workshop enables students to actively 'experience' a development concept rather than simply understand it in theory. It tests comprehension and understanding, through the application of a concept to real examples, stimulates discussion and debate, and draws upon problem-solving and critical thinking skills.  相似文献   
14.
This study presents the results of multi-element analysis of weak-acid extractions of 953 soil samples collected by coring on and around pre-historic village sites on two islands, Sanak and Amaknak, in the eastern Aleutians. Concentrations of aluminum (Al), barium (Ba), calcium (Ca), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), phosphorus (P), strontium (Sr), titanium (Ti), and zinc (Zn) were determined using an inductively coupled plasma-mass spectrometer (ICP-MS). Resultant elemental signatures allow the identification of site features and organization in the absence of large-scale excavation. All the archeological sites showed similar and distinct chemical signatures regardless of the several thousand year date range of the sites or the length of time a site was occupied. However, intensity of occupation does appear to affect concentrations of elements. Site features such as houses, house berms, house floors and middens had distinct anthropogenic signatures and could be distinguished from one another. This approach may be used to identify sites that do not have distinct surface features and to target areas for excavation.  相似文献   
15.
The aim of this study was to apply Nakamura's technique to Valencia city center, after some preliminary tests in Barcelona. Previous studies of Barcelona had measured periods in restrictive conditions and in various types of material ranging from very soft soil (with a predominant period of approximately 2 s) to rock (0.3 s), and under different measurement conditions. The Valencia city center measurements were taken by using the distance from buildings and car and pedestrian traffic to construct a measurement grid that was as regular as possible. We also estimated possible soil-structure interaction to detect potential vulnerability.  相似文献   
16.
This work was aimed at developing a practical and simple settlement estimation of shallow foundation on liquefiable deposits. The study conducted a centrifuge test, a series of comprehensive numerical analysis, back analysis, equation calibration, and verification with data from not only centrifuge test but also the literature. It finally proposed a quick calculation method based on Meyerhof’s settlement equation (1965). A two-dimensional numerical analysis, named ALID, (Analysis for Liquefaction-induced Deformation), was employed for obtaining settlement of shallow foundations on liquefiable soils with different relative densities under various seismic conditions. Its performance was first verified through a centrifuge test conducted in this study. Then, the developed method based on Meyerhof’s settlement equation was employed, and a new parameter, NLR, was proposed to present the strength of liquefied soils by replacing N value in the original equation. The NLR was obtained through back analysis of the numerical results and modified accordingly after comparison with the data from the literature. This paper, finally, demonstrated the practical use of the proposed method involving NLR by predicting 199 sets of liquefaction-induced settlement of shallow foundation reported in the past, including a latest most liquefaction-induced settlement of a house in 0206 earthquake on February 6, 2016, in Taiwan.  相似文献   
17.
EUROPE

France; A Geographical Survey. By P. Pinchemel, translated by C. Trollope and A. J. Hunt. 454 pp. Illustrations, Tables, Bibliography. Bell, London, 1969. 100s.

Italy. By George Kish. 8 × 5 1/4. 125 pp. 12 figures and index. Van Nostrand, New York, 1969. $1.lb95.

AFRICA

A Historical Geography of Ghana. By Kwamima B. Dickson. 15#lb5 × 23.lb5 cms. xiv + 379 pp., 58 maps and diagrams, 7 tables, appendices, bibliography, index. Cambridge U.P., London, 1969. 150s.

The Soil Resources of Tropical Africa. Edited by R. P. Moss. 8 1/2 × 5 1/2. Cambridge University Press, 1968. £2.

ASIA

Afghanistan. By Ludolph Fischer. Geomedical Monograph Series No. 2, 12 × 8 1/2. Text (German and English), 16 plates and 10 maps. Springer‐Verlag, Berlin, Heidelberg and New York, 1968. DM48, $12.lb00.

GEOLOGY AND GEOMORPHOLOGY

Readings in the Earth Sciences, Vols. 1 and 2. 11 1/4 × 8 1/2 Published W. H. Freeman, San Francisco, 1969. 94s. each.

Fife and Angus Geology. By A. R. MacGregor. 266 pp. Blackwood, Edinburgh and London, 1968. 21s.

METEOROLOGY

Essentials of Meteorology. By D. H. McIntosh and A. S. Thorn. 8 1/2 × 5 1/2. xv + 239 pp., numerous illustrations, answers to problems. Taylor and Francis, London. 20s.

ECONOMIC GEOGRAPHY

Industrial Britain: The North West. By David M. Smith. 10 × 6 1/4, 271 pp., 36 figures, 31 plates, bibliography and statistical appendix. David and Charles, Newton Abbot, 1969. 95s.

Industrial Demand for Water: A study of South East England. By Judith Anne Rees. 8 1/2 × 5 1/2 L.S.E. Research Monographs 3, xiv + 194 pp., Weidenfeld and Nicolson, 1969, London. 65s.

CARTOGRAPHY AND MAPS

The Antonine Wall. Ordnance Survey 2 1/2 Inch Map. 1969. 11s.

Maps and Air Photographs. By G. C. Dickinson. 10 × 17 1/2. xiv + 286 pp. Edward Arnold, London, 1969. 45s.

Atlas Four. 10 1/2 × 8 1/2. 115pages, + index 60 pages. Collins/Longmans, 1969. 15s.

EDUCATIONAL

Learning Through the Environment. By Muriel F. S. Hopkins. 7 3/4 × 5 1/8. 151 pages, 26 figures. Longmans, London. 1969. 15s.

Investigating Geography. By J. Philip Dodd. 9 3/4 × 7 1/4. 214 pp., 192 figures. Heinemann, London, 1969. 15s.

The London Regional Geographies. Book 3: Asia. By Leonard Hadlow and Reginald Abbott. 8 1/2 × 5 1/2. 294 pp., 145 figs. U. of London Press, 1969. 18s.

A Geography of Manufacturing. By H. R. Jarrett. 8 3/4 × 5 3/4. xvii + 349 pp. 67 illustrations. Macdonald &; Evans, 1969, London. 35s.

The Mediterranean Lands. By J. Brannigan and H. R. Jarrett. The New Certificate Geography Series: Advanced Level. 9 × 5l. xiv + 620, 150 illustrations. Macdonald and Evans Ltd., 1969. 38s.  相似文献   
18.
Analysis of detailed geomorphological mapping enables a sequence of glacial events to be established. An ice sheet whose source was to the west of the area of study is shown, by the suites of fluvioglacial landforms produced, to have down‐wasted in situ; meltwaters escaped beneath or through the ice, moving uphill across certain areas. Finally, a sub‐aerial drainage system was established and outwash terraces were spread down valley.  相似文献   
19.
Abstract

Semi-arid landscapes are vulnerable to cultivation, overgrazing and climate variability, although it is difficult to identify the relative significance of these three factors. In the South African Karoo, the ‘desertification debate' seeks to explain a change to more shrubby vegetation in heavily grazed areas. We examine these issues in catchments where farm reservoirs provide sediment stores with 137Cs, 210Pb, geochemical and mineral magnetic signatures. Rainfall data and stocking numbers are reported and current erosion rates are estimated. Sediment accumulation in the reservoirs increases between 1935 and 1940, probably due to rises in the frequency of rainfall events of >25mm day. Significant increases in sedimentation rates (×8) occur during rain-fed wheat cultivation. In an uncultivated catchment, sediment yields remain relatively high and reflect increases in erosion from hillslopes, colluvial storage, and cultivated land sources. Gully systems have acted as transport routes rather than sediment sources over the last ~70 years. Badland erosion rates average ca. 50t ha?1 yr?1. At Ganora, their development in the 1920s strongly influences peak sedimentation between 1970 and 1980. Any delay between badland initiation and increased sediment yield appears to be a function of landscape connectivity. Recovery following disturbance is occurring slowly and is likely to take >100 years. De-stocking and better management systems are reducing erosion rates but may be offset by increases in rainfall intensity.  相似文献   
20.
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