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991.
992.
993.
Gregor Gary L.; Smith Richard F.; Simons Lynn S.; Parker Howard B. 《Canadian Metallurgical Quarterly》1972,79(3):488
Hypothesized that, when the degree of crowding is manipulated by varying group size in cages of equal size, it is probable that crowded animals will engage in more contact than uncrowded animals. Home-cage observation of 24 male and 24 female deer mice indicates that crowded Ss do, in fact, engage in more contact behavior. Both home-cage observation and testing in pairs for pain-elicited aggression reveal that (a) crowded Ss display more agonistic behavior than uncrowded Ss, and (b) agonistic behavior increases with prolonged crowding. Support is obtained for the theory that the effect of crowding derives from contact with conspecifics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Two comparison groups of 25 Ss each, Fit and Lack of Fit, were generated based on extent of similarity between their ideal and real perceptions of a rehabilitation center on the Community-Oriented Program Environment Scale (an index of person/environment fit). Although Lack of Fit Ss reported more problems in receiving center services, more dissatisfaction with services, and lower life satisfaction in the present, they were no more likely to drop out of their center program. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Distortions in received signals in solar occultation measurements made from space arise as a result of the systematic motion of the electro-optical sensor. In a wide range of cases, the motion-related signal distortions caused by the instrument's full modulation transfer function are as important as those from the optics. This paper demonstrates by simulation that existing techniques in the field of digital-image processing can be applied directly to solar occultation experiments to correct for these distortions. The resulting enhanced radiation profile is much closer to the true radiance profile than is the sampled output of the instrument. Use of this enhanced radiance profile in the inversion computation should improve the retrieved atmospheric profiles considerably. It also contains a study of the accuracy of such application from the point of view of instrument noise, uncertainties in the knowledge of the instrument function, and the nature of the power spectrum of the undistorted signal. 相似文献
996.
Richard L. Liboff 《Annals of Nuclear Energy》1981,8(2):87-90
A Bose-atom model is introduced for the molecule DH where H represents a heavy halogen atom. A potential is constructed for this system and corresponding wavefunctions and energies are obtained. In the ground state, the large mass of the deuteron causes large penetration into the ion core. An expression for the probability of deuteron-nuclear overlap is obtained of the form where rN is nuclear radius, a0 is Bohr radius, Z is atomic number and . Thus P is infinitesimally small. Relevance to the exothermic reaction 127I(d,n) 128Xe is discussed. 相似文献
997.
Investigations of biofilms in domestic environments are sparsely represented in the literature. In this study, samples of various household surfaces, including food, laundry and kitchen items, were analyzed for evidence of biofilm presence. Visualization of the surfaces was carried out using cryostage scanning electron microscopy (CSEM) and light microscopy. Qualitative evidence of the presence of biofilm formation was obtained from all of the sample groups analyzed, suggesting the widespread existence of microorganisms in biofilms on domestic surfaces. This suggests that biofilms may be important in household hygiene, and highlights the need for standardized, approved biofilm methods suitable for consumer products testing. 相似文献
998.
Ruckart PZ Borders J Villanacci J Harris R Samples-Ruiz M 《Journal of hazardous materials》2004,115(1-3):27-31
High winds, flooding, lightning, and other phenomena associated with adverse weather can cause power failures, equipment damage, and process upsets resulting in chemical releases. Of the 5000 events in Texas that were reported to the Hazardous Substances Emergency Events Surveillance (HSEES) system during 2000-2001, adverse weather conditions contributed to 110 (2%) events. Rain was the most frequent adverse weather condition. Most events to which adverse weather conditions contributed occurred during June or September; these months correspond with the high temperature and hurricane season in Texas. Most events occurred in coastal counties with large numbers of industrial facilities. Three industries reported the majority of events: industrial and miscellaneous chemicals manufacturing; petroleum refining; and plastics, synthetics, and resin manufacturing. Power failures were associated more often with adverse weather-related events than with nonweather-related events. Releases occurred most commonly from ancillary process equipment and process vessels. Events associated with adverse weather-related conditions involved nine victims. System and process design improvements, such as improved backup power generation and redesigned secondary containment systems, could be explored to reduce the potential negative effects of severe weather. 相似文献
999.
Paul?FerkulEmail author Julie?Kleinhenz Hsin-Yi?Shih Richard?Pettegrew Kurt?Sacksteder James?T’ien 《Microgravity science and technology》2004,15(2):3-12
The conventional way of determining the flammability characteristics of a material involves a number of tedious single-sample
tests to distinguish flammable from non-flammable conditions. A novel test device and fuel configuration has been developed
that permits multiple successive tests for indefinite lengths of thin solid materials. In this device, a spreading flame can
be established and held at a fixed location in front of optimized diagnostics while continuous variations of test parameters
are made. This device is especially well-suited to conducting experiments in space (e.g. aboard the International Space Station)
where the limited resources of stowage, volume, and crew time pose major constraints. A prototype version of this device was
tested successfully in both a normal gravity laboratory and during low-gravity aircraft trials. As part of this ongoing study
of material flammability behavior, a numerical model of concurrent-flow flame spread is used to simulate the flame. Two and
three-dimensional steady-state forms of the compressible Navier-Stokes equations with chemical reactions and gas and solid
radiation are solved. The model is used to assist in the design of the test apparatus and to interpret the results of microgravity
experiments. This paper describes details of the fuel testing device and planned experiment diagnostics. A special fuel, developed
to optimize use of the special testing device, is described. Some results of the numerical flame spread model are presented
to explain the three-dimensional nature of flames spreading in concurrent flow and to show how the model is used as an experiment
design tool. 相似文献
1000.
Preparation and characterization of two new dielectric ceramics Ba4NdTiNb3O15 and Ba3Nd2Ti2Nb2O15 总被引:1,自引:0,他引:1
Liang Fang C. L. Diao Hui Zhang R. Z. Yuan Richard Dronskowski H. X. Liu 《Journal of Materials Science: Materials in Electronics》2004,15(12):803-805
Two new cation-deficient hexagonal perovskites Ba4NdTiNb3O15 and Ba3Nd2Ti2Nb2O15 were prepared in the BaO–Nd2O3–TiO2–Nb2O5 system by high temperature solid-state reaction route. The phase and structure of the ceramics were characterized by X-ray diffraction and scanning electron microscope (SEM). The microwave dielectric properties of the ceramics were studied using a network analyzer. Ba4NdTiNb3O15 has a dielectric constant of 38.15, a high-quality factors (Q
u
×f >18 700 at 5.4422 GHz), and a small temperature coefficient of resonant frequency (
f
)+12 ppm °C–1 at room temperature; Ba3Nd2Ti2Nb2O15 has a higher dielectric constant of 46.83 with high-quality factors Q
u
×f >19 500 at 5.0980 GHz, and
f
+28 ppm °C–1. 相似文献