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151.
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153.
Roger L. Creighton J. Douglas Carroll Jr. Graham S. Finney 《Journal of the American Planning Association. American Planning Association》2013,79(2):96-103
In city planning, data-processing machines permit the rapid handling and summarization of data in housing, renewal, land use, transportation, and basic urban research. Electronic computers. specifically, are exciting because they offer a means of solving complex city planning problems, especially in forecasting land use and travel demand. For most planning operations punched card data processing is superior to other processes. The functions of these machines are described herein and three examples of data processing are elaborated on. In future years, planning techniques may have to be altered considerably to take advantage of the potentials of data processing. 相似文献
154.
D. J. Walmsley 《Urban Policy and Research》2013,31(4):509-523
Examination of the changing composition of shopping centres in suburban Sydney between 1969 and 1998 suggests that retail restructuring is linked to lifestyle changes. The growth in the number of shops appears to have matched population growth in the 1990s, suggesting that the suburbanisation of retailing has stabilised. At the same time there has been increasing diversification in terms of the retail functions which are available and in terms of the places where these are available. These changes appear linked to a blurring of the distinction between shopping and leisure and to the use of shopping as a way of signifying identity. 相似文献
155.
156.
Globalization today encompasses multinational dialogues on the appropriate role for planning in mediating relationships between individual and community, state and citizen, government and market, and people and property. Yet confusion persists as speakers from one country attempt to convey concepts different from what listeners from another country hear. This paper provides a cross-national contemplation on the sources of that confusion, comparing the USA to Western Continental Europe, primarily Germany. Americans and Europeans engage fundamentally different worldviews in promoting progress while reconciling harms, stemming from different philosophical traditions that can be broadly characterized as a Millian versus a Hegelian liberalism, respectively. 相似文献
157.
This study highlights the effect of membrane action in improving load carrying capacity of Profiled Steel Sheeting Dry Board (PSSDB) floor system. PSSDB system is a lightweight composite structural system composed of profiled steel sheeting and dry board, attached together by self-drilling and self-tapping screws. Many literatures have reported that restricting conventional slabs, such as reinforced concrete slab, at the supports against translation and/or rotation while it is subjected to vertical loading develops the compressive membrane action in the slab. The development of this phenomenon is considered in the PSSDB system with concrete infill for continuous and practical spans, with and without topping concrete. Previous authors’ experimentally verified non-linear finite element model for the PSSDB floor without topping was extended to parametrically predict the effect of different boundary conditions on the performance of the system for practical applications. It was revealed that preventing the in-plane movement of the slab ends improves the flexural rigidities of the slab up to more than three times when considering central deflection of serviceability limit state. This was observed when the deflection limit load of the fixed both end supports model was compared to the pin-roller support model. Moreover, the topping concrete enhances the applicability of the system in longer span and the developed compressive membrane action dramatically boosts the load carrying capacity of the slab with restricted translation and/or rotation of the slab ends. 相似文献
158.
Sérgio Trajano Franco Moreiras Antenor Braga Paraguassú Gian Franco Napa 《Bulletin of Engineering Geology and the Environment》2014,73(4):1325-1330
Polished finishing granites are greatly accepted for claddings because of the plates’ shape, design and color variety. The features depend on the geological conditions that occur during the formation process, which include the mineralogy of the stone, the fluids formed during the process, the grain size of the minerals and the way in which the minerals interact with each other. One of the noblest uses of stone plates is in non-adherent covering systems (without mortar), such as ventilated façades and pedestrian paving systems. Currently, the methodology for non-adherent systems uses the allowable stress design criteria. In recent years, the number of papers indicating reliability analysis as an important design tool for natural stones has increased. However, a lack of information concerning the design methodology still happens. Therefore, the structural properties assessed as complementing these studies were: compressive strength, three-point flexural tensile strength, Young’s modulus and Poisson’s ratio. A granite slab design example was also presented. First, the thickness of the plates was determined based on the formulation proposed by Timoshenko [Strength of materials (original language, Portuguese), Volume II. Editora Ao Livro Técnico S. A., Rio de Janeiro, 1977], using the allowable stress design criteria. Next, the reliability analysis was performed by Monte Carlo simulation. Results showed that the Desireé White granitic plate presented a higher reliability index than the Capão Bonito Red granitic plate. This result seems to be paradoxical, owing that the Capão Bonito Red presented a higher value of mean flexural strength than the Desireé White. The minimal safety factors to satisfy the target reliability value of 3.8 as recommended by the standard EN 1990:2002 (Eurocode) were found to be 2.61, 1.98 and 2.72, respectively, for the three stone types. 相似文献
159.
A. N. Clarke W. W. Eckenfelder E. D. McMullen J. A. Roth B. A. Young 《Water research》1978,12(10):799-804
A continuous oxygen uptake meter or continuous respirometer was developed which produced a rapid and reliable response to systemic shocks. The respirometer basically is a 101. Plexiglas laboratory activated sludge unit with a variable volume air tight side car. The feed enters the completely mixed aeration basin and is pumped into the side car. The side car is the site of the oxygen uptake measurements as indicated by a continuously monitoring dissolved oxygen probe. The system was most sensitive to changes in influent concentrations when run at an F/M = 0.1. Response time for a change in DO of 0.1 ppm was less than 4 min. The continuous respirometer was tested employing both synthetic and raw industrial wastes. 相似文献
160.
Herbert BM Halsall CJ Villa S Fitzpatrick L Jones KC Lee RG Kallenborn R 《The Science of the total environment》2005,342(1-3):145-160
PCNs were measured in air and snow during separate field campaigns at Ny-Alesund (April 2001) and Troms? (February/March 2003) in the Norwegian Arctic. Air concentrations ranged from 27 to 48 and 9 to 47 pg sigmaPCN m(-3) for Ny-Alesund (n=6) and Troms? (n=10), respectively. These concentrations (including the tri-chlorinated naphthalenes) greatly exceeded concentrations previously measured in the Canadian Arctic, but did fall within the upper range of concentrations observed over the eastern Arctic Ocean and regional seas. Local sources appear to be affecting concentrations observed at both sites, with the presence of several hexa-chlorinated naphthalenes at Troms? probably attributed to local/regional sources. Use of air mass back trajectories at Troms? revealed that background air concentrations in the Norwegian Arctic are likely to range between <9 and 20 pg sigmaPCN m(-3) and that contemporary concentrations derived close to potential sources (i.e. arctic towns) may equal or exceed those of PCBs. The mean concentration in surface snow was 350 and 240 pg sigmaPCN L(-1) (meltwater) (or 0.014 and 0.01 pg g(-1) (snow)) at Ny-Alesund and Troms?, respectively. The wide variation in concentrations observed between fresh snowfalls could be explained by different snow densities (as a surrogate of snow surface area), rather than attributed to varying air concentrations. A statistically significant inverse relationship was found between snow density and concentrations of tri- to penta-chlorinated homologues and compliments similar findings for the polychlorinated biphenyls (PCBs). This suggests that the vapour-sorbed quantity changes rapidly with snow ageing/compaction; with implications for the fate of these chemicals in the Arctic. 相似文献