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981.
The Sethi-Ullman algorithm for register allocation finds an optimal ordering of a computation tree. Two simple generalizations of the algorithm increase its applicability without significantly increasing its cost. 相似文献
982.
Schwartz Barry; Ward Andrew; Monterosso John; Lyubomirsky Sonja; White Katherine; Lehman Darrin R. 《Canadian Metallurgical Quarterly》2002,83(5):1178
Can people feel worse off as the options they face increase? The present studies suggest that some people--maximizers--can. Study 1 reported a Maximization Scale, which measures individual differences in desire to maximize. Seven samples revealed negative correlations between maximization and happiness, optimism, self-esteem, and life satisfaction, and positive correlations between maximization and depression, perfectionism, and regret. Study 2 found maximizers less satisfied than nonmaximizers (satisficers) with consumer decisions, and more likely to engage in social comparison. Study 3 found maximizers more adversely affected by upward social comparison. Study 4 found maximizers more sensitive to regret and less satisfied in an ultimatum bargaining game. The interaction between maximizing and choice is discussed in terms of regret, adaptation, and self-blame. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
983.
Thom J. Hodgson Russell E. King Kristin Thoney Natalie Stanislaw Alexander J. Weintraub Andrew Zozom 《IIE Transactions》2000,32(2):177-180
We consider the problem of minimizing maximum lateness in a job shop. A conceptually simple simulation based procedure described in a recent paper by Hodgson et al [1] is modified to provide improved schedules. Computational experimentation is provided to identify the conditions under which the approach is most viable, and to report the procedure's performance on known test problems. 相似文献
984.
A nucleic acid sensor capable of automated sample and reagent loading, real-time PCR, automated detection, and sample line cleaning was tested. Real-time PCR reactions were performed with Salmonella enterica in autoclaved and spent alfalfa sprout irrigation water. S. enterica boiled cells were detected over a range of approximately 104 to 108 CFU/reaction (rxn). It was possible to generate enough PCR product to visualize a band on a gel at the expected size over approximately five orders of magnitude from 3.2 × 103 to 108 CFU/rxn. Automated detection experiments yielded correct identification of 9/9 positive control reactions over a range of 104 to 108 CFU/rxn, correctly identified a negative control reaction, and a sample of 3.2 × 103 CFU/rxn was incorrectly identified as negative. Primer dimers were not seen in positive or negative control reactions with sprout irrigation water, suggesting that it may be possible to improve the detection limit simply by increasing the number of thermal cycles or by lowering the annealing temperature. The system required no interpretation of real-time PCR data by the operator. The entire process of loading, running the PCR, automated data interpretation, and sample line cleaning was completed in under 2 h and 20 min, significantly faster than it would take to ship a sample and have it tested by an independent laboratory. 相似文献
985.
Accuracy of timing in circuits and systems using nanoscale transistors is crucial and is dependent, to first order, on the
capacitances of the load transistors. It is accepted that variation in parameters will be intrinsic to such devices due to,
among other factors, the discrete nature of the doping. It is likely that one such parameter exhibiting variation will be
capacitance. Here we investigate, using 3-dimensional simulation, the fluctuation in gate and drain capacitance in a 30 nm
MOSFET due to random discrete doping. 相似文献
986.
987.
988.
A Couette-type torsion wire surface shear viscometer was used to measure the apparent interfacial shear viscosity of pH 7
(I=0.05 M) buffered solutions of sodium caseinate in contact with sunflower oil. The sunflower oil contained 1% fat crystals
in either the β or β′ polymorphic form, or was crystal free. In all cases, the fat crystals increased the interfacial shear
viscosity synergistically, with the β′ crystals causing the biggest increase. Substituting the protein for a small-molecule
surfactant (Tween-40) showed that this was not simply due to the protein lowering the interfacial tension. Sedimentation studies
of the different fat crystal slurries suggested that the extent of the interfacial shear viscosity increase was related to
the strength of crystal-crystal interactions in the oil phase. It seems likely that when protein is present at the interface,
it fixes the adsorbed layer of fat crystals to the cross-linked protein film at the interface. When this film was sheared,
the strength of the crystal-crystal interactions in the oil phase became important. However, when Tween-40 was in the aqueous
phase instead of the protein, the crystal-crystal interactions were not relevant, presumably because the Tween-40 interfacial
film simply flowed around the adsorbed crystals 相似文献
989.
The empirical focus is two small adjacent estates in West Newcastle; one with a mostly Bangladeshi population, the other white. The contrasts between them form the basis for a discussion of low housing demand and high turnover; forms of social exclusion; community and ethnicity. The Bangladeshi population experience exclusion from housing. Their estate has high demand and low turnover. Their housing options are highly constrained by a combination of low income and fear of crime and harassment. On the other hand they are comparatively well integrated into the local economy and a strong community structure. In contrast, the white population has more housing choice as a result of low demand, but exhibit greater exclusion from the labour market and from 'civil society'. Recent proposals to restructure the housing of the West End could increase housing opportunities for the Bangladeshis, but their impact on the white estate is more uncertain. 相似文献
990.
Case Study: Modeling Tidal Transport of Urban Runoff in Channels Using the Finite-Volume Method 总被引:1,自引:0,他引:1
Brett F. Sanders Carrie L. Green Allyson K. Chu Stanley B. Grant 《Canadian Metallurgical Quarterly》2001,127(10):795-804
A coupled flow and pollutant transport model based on the finite-volume method is developed and applied to predict the tidal transport of urban runoff in a southern California network of flood control channels that drain to near-shore bathing waters. Urban runoff in southern California contains elevated levels of indicator bacteria that signal the presence of fecal pollution and pose a risk to human health, and model predictions are used to understand the transport of these pollutants toward the coastline. The model is based on 1D conservation equations for fluid mass, momentum, and pollutant mass that are solved in integral form along channel reaches. A 2D formulation is solved at channel junctions. The model incorporates the monotone upwind scheme for conservation laws approach to give a high-resolution, nonoscillatory prediction of water level, velocity, and pollutant concentration. Model predictions and field measurements of water level, velocity, and a conservative urban runoff tracer are presented and compare favorably. This case study demonstrates that this finite-volume method–based scheme results in an accurate, stable, nonoscillatory and computationally manageable model. The nonoscillatory behavior is particularly beneficial in this study, since runoff enters the channels in pulses that create large gradients in pollutant concentration. 相似文献