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31.
Guimond Serge; Dambrun Micha?l; Michinov Nicolas; Duarte Sandra 《Canadian Metallurgical Quarterly》2003,84(4):697
Social dominance orientation (SDO) has been proposed as an important variable in the explanation of prejudice. We distinguish between three conceptualizations of SDO: SDO as a personality trait (personality model), SDO as a moderator of the effects of situational variables (Person X Situation model), and SDO as a mediator of the effect of social position on prejudice (group socialization model [GSM]). Four studies (N = 1,657) looking at the relations between social positions, SDO, and prejudice in a natural setting and in a laboratory setting provide strong support for the GSM. In contrast to previous correlational findings, there is evidence of a cause (dominant social position), an effect (prejudice increases), and a mediator (SDO). These results suggest new perspectives on the integration of individual and contextual determinants of prejudice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
Thin layers of silver and titanium were deposited onto commercial Ti–48Al particles by magnetron sputtering prior to their consolidation by hot isostatic pressing and subsequent heat treatment.
Based on picnometry and electron probe microanalysis results, average values of 1.5 and 2.5 at.%, respectively, were obtained
for the silver and titanium contents in the coated particles. The surface modified Ti–48Al particles exhibited improved sintering ability than the unmodified ones. The consolidated samples have duplex microstructures
formed by γ-TiAl and γ-TiAl + α2-Ti3Al grains. Ag-rich nanoprecipitates were detected in the microstructure of the compacted Ti-48Al + Ag sample. The coatings are no longer visible at the grains boundaries after a subsequent homogenization heat treatment
at 1200°C. The highest values of hardness and Young’s modulus were obtained for the Ti–48Al + Ag sample, associated with a higher density and a lower percentage of pores. 相似文献
33.
This paper introduces a new single-phase high power factor rectifier, which features regulation by conventional PWM, soft commutation and instantaneous average line current control. Furthermore, thanks to the use of a single converter, instead of the conventional configuration composed of a four-diode front-end rectifier followed by a boost converter, a significant reduction in the conduction losses is achieved. A prototype rated at 1.6 kW, operating at 70 kHz, with an input AC voltage of 220 Vrms and an output voltage of 400 VDC has been implemented in the laboratory. An efficiency of 97.8 % at 1.6 kW has been measured. Analysis, design, and the control circuitry are also presented in the paper 相似文献
34.
J. R. Prez-Correa F. R. Sepúlveda M. A. Duarte 《International Journal of Adaptive Control and Signal Processing》1995,9(2):183-197
This paper presents experimental results obtained in temperature adaptive control of a heating vessel. A non-linear model of the process showed that the feed flow rate causes severe variations in time constant and process gain. An extended horizon self-tuning controller and two different model reference adaptive controllers were tested. The influence of design parameters on control performance for each algorithm was assessed. The control system was disturbed with load and setpoint changes. 相似文献
35.
RM Hendry CV Hanson V Bongertz M Morgado A Duarte J Casseb L Brigido E Sabino R Diaz B Galv?o-Castro 《Canadian Metallurgical Quarterly》1996,91(3):347-348
The influence of noncompetitive (MK-801), competitive (AP-7) and the antagonist of polyamines site of NMDA receptor (arcaine) on the central activity of angiotensin II (A II) was studied. The open field test, conditioning of active avoidance responses (CARs) and passive avoidance situation was used to investigate learning and memory in rats. All used antagonists decreased beneficial action of A II on these processes. 相似文献
36.
37.
Mardia K.V. Wei Qian Shah D. de Souza K.M.A. 《IEEE transactions on pattern analysis and machine intelligence》1997,19(9):1035-1042
Based on deformable templates, the paper formulates an integrated and flexible Bayesian recognition system of multiple occluded objects. Various local dependence properties of the model are obtained to reduce the computational cost with the increase in the number of objects. Numerical results for a synthetic image and for a real image of mushrooms are discussed 相似文献
38.
T Tokano F Pelosi M Flemming L Horwood JJ Souza A Zivin BP Knight R Goyal KC Man F Morady SA Strickberger 《Canadian Metallurgical Quarterly》1998,9(9):916-920
INTRODUCTION: Defibrillation energy requirements in patients with nonthoracotomy defibrillators may increase within several months after implantation. However, the stability of the defibrillation energy requirement beyond 1 year has not been reported. The purpose of this study was to characterize the defibrillation energy requirement during 2 years of clinical follow-up. METHODS AND RESULTS: Thirty-one consecutive patients with a biphasic nonthoracotomy defibrillation system underwent defibrillation energy requirement testing using a step-down technique (20, 15, 12, 10, 8, 6, 5, 4, 3, 2, and 1 J) during defibrillator implantation, and then 24 hours, 2 months, 1 year, and 2 years after implantation. The mean defibrillation energy requirement during these evaluations was 10.9+/-5.5 J, 12.3+/-7.3 J, 11.7+/-5.6 J, 10.2+/-4.0 J, and 11.7+/-7.4 J, respectively (P = 0.4). The defibrillation energy requirement was noted to have increased by 10 J or more after 2 years of follow-up in five patients. In one of these patients, the defibrillation energy requirement was no longer associated with an adequate safety margin, necessitating revision of the defibrillation system. There were no identifiable clinical characteristics that distinguished patients who did and did not develop a 10-J or more increase in the defibrillation energy requirement. CONCLUSION: The mean defibrillation energy requirement does not change significantly after 2 years of biphasic nonthoracotomy defibrillator system implantation. However, approximately 15% of patients develop a 10-J or greater elevation in the defibrillation energy requirement, and 3% may require a defibrillation system revision. Therefore, a yearly evaluation of the defibrillation energy requirement may be appropriate. 相似文献
39.
In the present work we investigated the mechanisms controlling the release of acetylcholine (ACh) and of gamma-aminobutyric acid (GABA) from cultures of amacrine-like neurons, containing a subpopulation of cells which are simultaneously GABAergic and cholinergic. We found that 81.2 +/- 2.8% of the cells present in the culture were stained immunocytochemically with an antibody against choline acetyltransferase, and 38.5 +/- 4.8% of the cells were stained with an antibody against GABA. Most of the cells containing GABA (87.0 +/- 2.9%) were cholinergic. The release of acetylcholine and GABA was mostly Ca2+-dependent, although a significant release of [3H]GABA occurred by reversal of its transporter. Potassium evoked the Ca2+-dependent release of [3H]GABA and [3H]acetylcholine, with EC50 of 31.0 +/- 1.0 mm and 21.6 +/- 1.1 mm, respectively. The Ca2+-dependent release of [3H]acetylcholine was significantly inhibited by 1 micrometer tetrodotoxin and by low (30 nm) omega-conotoxin GVIA (omega-CgTx GVIA) concentrations, or by high (300 nm) nitrendipine (Nit) concentrations. On the contrary, the release of [14C]GABA was reduced by 30 nm nitrendipine, or by 500 nm omega-CgTx GVIA, but not by this toxin at 30 nm. The release of either transmitters was unaffected by 200 nm omega-Agatoxin IVA (omega-Aga IVA), a toxin that blocks P/Q-type voltage-sensitive Ca2+ channels (VSCC). The results show that Ca2+-influx through omega-CgTx GVIA-sensitive N-type VSCC and through Nit-sensitive L-type VSCC induce the release of ACh and GABA. However, the significant differences observed regarding the Ca2+ channels involved in the release of each neurotransmitter suggest that in amacrine-like neurons containing simultaneously GABA and acetylcholine the two neurotransmitters may be released in distinct regions of the cells, endowed with different populations of VSCC. 相似文献
40.
The 1990s has already seen enormous change to the computer industry in Brazil. But the greatest change of all is expected in the area of software. By the end of 2000, Brazil is out to capture 1 percent of a US $ 200 billion international software market, according to the federal Govemment's National Program of Software for Export, or Softex 2000. For Brazil, this could mean $2 billion in revenues from sales of application programs, programming tools, and multimedia entertainment and educational systems on CD-ROMs. So far, the local industry has done well. Exports in 1995 reached $100 million, about half going to the United States, again according to Softex. This occurred even though most of the Softex-supported companies still have to make their mark overseas. In 1994, Brazilian companies sold a total of $1.1 billion worth of software, which puts the industry on a par with that of India's far better known software industry, though exports account for about half of India's revenues. Brazil's software industry grew by about 25 percent over the year before. Revenues from information technology hardware, software, and services in 1994 were around 2 percent of Brazil's gross domestic product of about $552 billion 相似文献