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151.
AbstractContemporary wisdom holds that landscape research requires cross-disciplinary collaborations, and consideration of character has been seen as one way to achieve this, yet character-based methods of landscape assessment incline towards unidisciplinarity. This is the case in the UK, with two parallel methods in use since the early 1990s. Both have become influential across Europe in the drafting and implementation of the European Landscape Convention. This paper, a contribution to a special issue of Landscape Research, focuses on one of the methods, Historic Landscape Characterisation (carried out mainly by archaeologists and heritage managers), and compares it with Landscape Character Assessment (used by the landscape architects and geographers) to examine the concepts of both landscape character and interdisciplinarity. It concludes that although a single integrated method for landscape assessment could be desirable, there remain benefits in having separate methods, and the process of combining parallel landscape assessments can bring research benefits. 相似文献
152.
Land use change and soil organic carbon dynamics 总被引:7,自引:0,他引:7
Pete Smith 《Nutrient Cycling in Agroecosystems》2008,81(2):169-178
Historically, soils have lost 40–90 Pg carbon (C) globally through cultivation and disturbance with current rates of C loss
due to land use change of about 1.6 ± 0.8 Pg C y−1, mainly in the tropics. Since soils contain more than twice the C found in the atmosphere, loss of C from soils can have
a significant effect of atmospheric CO2 concentration, and thereby on climate. Halting land-use conversion would be an effective mechanism to reduce soil C losses,
but with a growing population and changing dietary preferences in the developing world, more land is likely to be required
for agriculture. Maximizing the productivity of existing agricultural land and applying best management practices to that
land would slow the loss of, or is some cases restore, soil C. There are, however, many barriers to implementing best management
practices, the most significant of which in developing countries are driven by poverty. Management practices that also improve
food security and profitability are most likely to be adopted. Soil C management needs to considered within a broader framework
of sustainable development. Policies to encourage fair trade, reduced subsidies for agriculture in developed countries and
less onerous interest on loans and foreign debt would encourage sustainable development, which in turn would encourage the
adoption of successful soil C management in developing countries. If soil management is to be used to help address the problem
of global warming, priority needs to be given to implementing such policies. 相似文献
153.
This study uses several years of effluent quality data from 43 sites where online monitoring has been operational for many years resulting in the accumulation of high-resolution data sets. The data show a highly repeatable, seasonal dependence of effluent turbidity on temperature. This has been modelled with simple techniques producing a generic model that is neither data hungry nor requires site calibration. Viscosity-based mechanisms are proposed and discussed. These mechanisms differ from conventional assumptions of suspended solids peaks being solely flow related and or ascribed to ‘spring sloughing’. The proposal is that the organic loading of the filter and the physical temperature effects on settlement velocity are both as influential as hydraulic loading in determining effluent suspended solids concentration. Application of the models enables improved design for new/upgraded units and more accurate capacity assessment of trickling filters and humus tanks enabling improved operational risk management of compliance failure. 相似文献
154.
Doug H. Rose Falah S. Hasoon Ramesh G. Dhere Dave S. Albin Rosine M. Ribelin Xiaonan S. Li Yoxa Mahathongdy Tim A. Gessert Pete Sheldon 《Progress in Photovoltaics: Research and Applications》1999,7(5):331-340
This paper details the laboratory processes used to fabricate CdS/CdTe solar cells at the National Renewable Energy Laboratory. The basic fabrication technique includes low‐pressure chemical vapor deposited SnO2 , chemical‐bath deposited CdS, close‐spaced sublimated CdTe, solution‐CdCl2 treatment, and an acid‐contact etch, followed by application of a doped‐graphite paste. This paper also describes the results of a reproducibility study in which cells were produced by multiple operators with an average AM1·5 efficiency of 12·6%. And finally, this paper discusses process sensitivities and alternative cell fabrication procedures and reports the fabrication of a cell with an AM1·5 efficiency of 15·4%. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
155.
Benjamin Kowalski Jamesa Stokes Patrick E. Albert Pete E. Lauer Douglas E. Wolfe 《Journal of the American Ceramic Society》2023,106(6):3911-3921
Jet engine components need protective coatings to function against both high-temperature and environmental effects. Ingested calcium–magnesium–aluminosilicates (CMAS) dust particulates are extremely detrimental to the life of the coatings. However, many methods exist to investigate the infiltration of CMAS into these coatings with each method exploring a different aspect of the degradation process. To probe the overlap in these methods, this study focuses on the effect of grain size, areal density, and aspect ratio on the infiltration of CMAS into yttria stabilized zirconia. The infiltration depths ranged from 6 up to 85 µm depending on the test conditions. 相似文献