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1.
The architects and builders in the past lacked our knowledge concerning fluid dynamics, but they exhibited a deep rooted ability to observe and reflect - thus, different cultures have developed by trial and error. The authors have produced a stimulating analysis which couples the science of fluid dynamics and a sensitive understanding of past cultures. The paper is recommended reading.  相似文献   
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Urbanization impacts ecosystems through loss and fragmentation of habitat, loss of diversity, increase in runoff, and contaminant discharges, and the invasion of exotic species. Potrero de los Funes Village (San Luis, Argentina) is experiencing not only a population increase during summer months due to tourism but also an accelerated growth of its permanent population. In order to evaluate the potential effects of urbanization, the environmental quality of Potrero de los Funes River and Las Chacras Stream was assessed, using physical–chemical and biological indicators. Macroinvertebrates, through the application of the Biotic Index for San Luis Sierras (BISLS), anuran amphibian richness and relative abundance, and riparian vegetation were used as bioindicators. While the Simplified Index of Water Quality (SIWQ) was used to characterize the physical–chemical quality of water at each site. SIWQ and BISLS scores were significantly different between sites (F7,28 = 9.88, p < .001 and F7,28 = 24.18, p < .001, respectively). SIWQ was significantly correlated with BISLS (Spearman correlation coefficient = 0.8, p < .001). Four anuran species were registered along Potrero River, with no significant differences in the intensity of vocalizations between sites. No species were detected in Las Chacras Stream. Average total plant species richness, exotic plants richness, and vegetation cover were higher at the most impaired system, Las Chacras Stream. The principal component analysis showed that the first two principal components (PCs) explained 76.3% of the total variance. PC1, with strong loadings of SIWQ, BISLS, and amphibian richness, was principally driven by chemical water quality and biological conditions. PC2 was mainly determined by plant richness. The chemical and biological water quality of Potrero and Las Chacras is somewhat impaired, being the upper Las Chacras Stream the most compromised area. This study provides information that will certainly be used to manage future impacts of urbanization on aquatic resources.  相似文献   
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What defines the urban? And can the non-urban necessarily always be classified as rural? Neil Brenner , Director of the Urban Theory Lab at Harvard University Graduate School of Design, reflects on the lack of an overarching theory to describe these realms, and argues that what we call the countryside or the hinterland has become key to the process of capitalist urbanisation.  相似文献   
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This study deals with the effects of climate fluctuations and anthropogenic impacts on fisheries of Paraná River over the last 100 years. It is the first attempt to appraise the influence of hydro‐climatic and anthropogenic variables on the population changes of the most important inland fisheries of Argentina. Datasets covering more than eight decades (1935–2016) of a number of frequent and abundant commercial species inhabiting the main channel as well as the large floodplain of Paraná River were used. Our results suggest that fish catches and structure changed over time. Long and short‐term changes and reductions were closely related to fluctuations of 18 hydro‐climatic variables. Positive effects on the ichthyofauna were recorded during humid periods (1930–1940 and 1970–2000), when the frequency of large spring–summer floods increased. An increase in anthropic impacts (accounted for with nine variables) were recorded during the last two decades. We highlight the usefulness of the approach to support the management of the resources, ensuring sustainability of commercial fish assemblages and the long‐term conservation of biodiversity in big rivers.  相似文献   
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This article explores the chromatic reconstruction of La Boca neighborhood of Buenos Aires, Argentina and seeks to protect its patrimonial heritage. This article is organized into three parts: an Introduction, a section entitled Searching for Colours, and a Conclusion. The Introduction explains the historical factors contributing to the large‐scale Italian immigration that settled in La Boca neighborhood as well as their influence in shaping the character and landscape of the area. This section also comments on the emergence of the zone's brightly coloured homes, which have become a trademark of the neighborhood. The second section, Searching for Colours, details the composition of the paints made and used by La Boca residents, in addition to the field research, the method of analysis and the results of the study. The Conclusion highlights the importance of preserving areas of significant historical and patrimonial heritage such as La Boca, an ever more timely challenge in an increasingly globalized world. © 2010 Wiley Periodicals, Inc. Col Res Appl, 36, 222–228, 2011;  相似文献   
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This article focuses on the relationship between theoretical orientation and clinical practice in Argentina. Five hundred twenty-five psychotherapists were surveyed in the city of Buenos Aires and the provinces of Buenos Aires, Santa Fe, La Pampa, Neuquén, Chubut, and Rio Negro. Psychoanalysis was chosen by 53.1% of the psychotherapists as the main theory used in their clinical practice. Integrationists made up 39.8% of the sample and represented the 2nd most important group. Within the integrationist group, psychoanalysis was mentioned by 63.2% as the main or base theory, followed by 12.9% mentioning cognitive theory. A longitudinal analysis shows how the trend toward integration of the different theories has grown over the years. These results reveal the importance of psychoanalysis and the trend toward integration within clinical practice in Argentina. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Argentine water resources are located in three hydrologically contrasting regions: the so-called Del Plata basin, the Arid Central Andean area, and Patagonia. About 150 dams and impounding reservoirs that exceed a capacity of 150 × 103 m3, have been built. Most limnological studies of regulated rivers have been conducted recently. In the Del Plata basin, Argentine dams are scarce, although many have been built or are projected upstream, mainly in Brazil. The ecological problems of the reservoirs are related to decomposition of inundated terrestrial vegetation; algae blooms, dissolved oxygen depletion phenomena, eutrophication, impaired fish migrations, overproduction of water hyacinth Eichhornia spp., and schistosomiasis. The importance of examining the influence of the projected middle Paraná dams on downstream sediment regimes, especially as it affects the delta, is emphasized. In the Arid or Central Andean region, the main development of the Grande-Tercero rivers includes dams, reservoirs, and the operation of a nuclear power plant. One of the most important effects will be a slight increase in the water temperature of the Rio Tercero reservoir as a consequence of water use in the cooling system of the nuclear power plant. In the Patagonian region, the main dams are those built and projected for the Colorado and Negro basins. In the Negro basin studies are being carried out mainly in the Ramos Mexia Reservoir, on different aspects of zooplankton and phytoplankton, benthos, and fishes. Commercial fishing is not permitted and fishing is based mainly on the introduced salmonids which show symptoms of undernourishment because of a lack of forage fishes. Indigenous fishes have been decimated by the introduced salmonids. Although studies have been conducted in several areas, much work remains to be done in relation to the environmental effects of dams on streams in Argentina. Results from ecological studies are still insufficient to solve the multiple problems associated with them, such as climatic influences, retention of suspended solids, deforestation, schistosomiasis and other aquatic diseases, pollution, eutrophication, fish-ways and fish migrations, accumulations of the water-hyacinth, salt and nutrient regimes, and siltation. Even partial solutions to these problems will require an ensemble of urgent measures to assure the maximum benefits with minor risks and ecological costs.  相似文献   
10.
An electrical resistivity survey was performed at the estuary of the Rio de la Plata, as part of more comprehensive geotechnical investigations of the subsurface conditions. The studies were required for the emplacement of a 3.5-m-diameter conduit proposed for the discharge of the treated wastewater of the city of Buenos Aires. The soil profile at the site consists mainly of clays and silts underlain by a layer of dense sand. The dense sand layer is a confined aquifer, and the project required that the depth to the sand layer be perfectly determined. Previous geophysical surveys at the site and the general geotechnical conditions showed the inadequacy of seismic methods, which are usually adopted in similar environments. The resistivity method was determined to be a reliable alternative, even though there has been little experience in surveying shallow depth water for geotechnical investigations. The four-electrode Schlumberger electrode array was adopted for the resistivity survey. Some of the test devices were developed especially for the purpose of this project. Calibration of the method was achieved with data obtained from boreholes. The results show that the resistivity technique performed satisfactorily to the 40?m depth required in this project. As a result of the survey, the next geotechnical investigation was focused on a more reduced area and the required number of boreholes was reduced substantially.  相似文献   
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