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991.
When people switch between languages, inhibition of currently irrelevant languages is assumed to occur. The authors examined inhibition of irrelevant languages with a cued language-switching paradigm. A cue indicated in which of 3 languages (German, English, or French) a visual stimulus was to be named. In 2 experiments, the authors found that naming latencies were increased in n-2 language repetitions (e.g., German/English/German) compared with in n-2 language nonrepetitions (e.g., French/English/German). This difference (n-2 repetition costs) indicates persisting inhibition of abandoned languages. It is important to note that n-2 language-repetition costs also occurred in conditions in which the language but not the cue (Experiment 1) or the stimulus/response set (Experiment 2) repeated from trial n-2 to trial n. These data demonstrate that inhibition is not restricted to a specific cue or stimulus/response set. Rather, the data suggest more global inhibitory processes that affect the mental representation of competing languages. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Hot tests of foaming behaviour of steelmaking slags were conducted on a laboratory scale up to 1760 °C using a Tammann furnace. The foaming behaviour of the slags was quantified on the basis of a new measuring method. The volume increase and the progress of the foaming process can be continuously observed and calculated by means of picture analysis. The gas content of foaming slags was compared with the results of the measurements performed in steel plants. The influence of the magnesia content on the foaming behaviour is investigated. The chemical composition of the slag is beside the CO evolution the decisive factor influencing slag foaming behaviour. The highest volume increase values observed lie in the region of 2500 % in relation to the initial volume. 相似文献
993.
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995.
We study Nash equilibria in the context of flows over time. Many results on static routing games have been obtained over the last ten years. In flows over time (also called dynamic flows), flow travels through a network over time and, as a consequence, flow values on edges are time-dependent. This more
realistic setting has not been tackled from the viewpoint of algorithmic game theory yet; but there is a rich literature on
game theoretic aspects of flows over time in the traffic community. 相似文献
996.
Keratoconus is a bilateral degenerative disease characterized by a non-inflammatory, progressive central corneal ectasia (typically asymmetric) and decreased vision. In its early stages it may be managed with spectacles and soft contact lenses but more commonly it is managed with rigid contact lenses. In advanced stages, when contact lenses can no longer be fit, have become intolerable, or corneal damage is severe, a penetrating keratoplasty is commonly performed. Alternative surgical techniques, such as the use of intra-stromal corneal ring segments (INTACS) have been developed to try and improve the fit of rigid contact lenses in keratoconic patients and avoid penetrating keratoplasties. This case report follows through the fitting of rigid contact lenses in an advanced keratoconic cornea after an INTACS procedure and discusses clinical findings, treatment options, and the use of mini-scleral and scleral lens designs as they relate to the challenges encountered in managing such a patient. Mini-scleral and scleral lenses are relatively easy to fit, and can be of benefit to many patients, including advanced keratoconic patients, post-INTAC patients and post-penetrating keratoplasty patients. 相似文献
997.
Eckhart Koch 《Stahlbau》2006,75(10):786-790
Railwaybridges of Deutsche Bahn AG. New technical and stratgical approaches. Railway bridges as composite structures are good technical and economical solutions in the field of bridge design. A research project to composite bridge structures has been carried out. The investigations have shown, that composite bridge structures with prefabricated elements are good solutions. In an other project in the field of hollow section structures the fatige life of such bridge structures will be investigated. The extension of the lifetime of bridge structures with an post weld treatment will also be investigated 相似文献
998.
Bennett CM McKendry IG Kelly S Denike K Koch T 《The Science of the total environment》2006,366(2-3):918-925
The adverse public health impacts of anthropogenically derived particulate matter have been well documented, with measurable increases in both morbidity and mortality rates associated with high particulate matter pollution events. Most current research has focussed on the health impacts of anthropogenically derived particulate matter, and there is a distinct scarcity of literature that examines the role of naturally derived particulate matter and adverse health impacts in the urban context. This study of a Gobi desert dust event in the Greater Vancouver region of British Columbia, Canada, in spring of 1998 provided a unique opportunity to identify the adverse health effects related to naturally derived particulate matter in a large urban setting. Respiratory and cardiac hospitalizations were examined for a three-year period (January 1997 to December 1999), with the Gobi dust event occurring in late April 1998. A meteorological analogue was identified for spring 1997 in order to identify the public health impacts associated with anthropogenically derived particulate matter and those impacts associated with the presence of the Gobi desert dust. Results indicate that this Gobi dust event was not associated with an excess of hospitalizations in the Greater Vancouver region. Peak particulate matter concentrations of Gobi desert dust in the airshed were only associated with an additional one or two hospitalizations per 100,000 population for respiratory and cardiac illnesses, and these increases were not distinguishable from the 'normal' variability in hospitalization rates. Despite high particulate matter concentrations, fine particle size, presence of heavy metals in the dust and extended exposure periods, it appears that the Gobi desert dust event was not associated with significant risk to public health in Greater Vancouver, British Columbia. Therefore it is concluded that naturally derived particulate matter is more benign than particulate matter of anthropogenic origin, and thus poses a low risk to health for the general public. 相似文献
999.
Morgenstern V Bischof W Koch A Heinrich J 《The Science of the total environment》2006,370(2-3):574-579
At present there exist unsolved questions, whether endotoxin measurements on PM filters show valid measurements after long-term storage of loaded PM filters. As part of the TRAPCA study we collected particles with a 50% aerodynamic cut-off diameter of 2.5 microm (PM(2.5)) at 40 outdoor sites and particles less than 10 microm in size (PM(10)) at a subset of these sites (N=12) in Munich. The PM filters were cut in halves and endotoxin was measured in the extract of one filter half 2-3 years after PM collection. Here we present the results of repeated endotoxin measurements, where the association between previously measured endotoxin concentrations, measurements from stored eluates, and measurements in extracts of the second filter halves were determined. No statistically significant changes were seen between our old measurements and those from the stored eluates. Additionally, no change was observed between previously measured endotoxin concentrations and those from the stored set of filter halves. We found an average increase of 5% between our old measurements and those from the stored eluates and of 19% between the old measurements and those from the stored set of filter halves. The correlations between the previously measured endotoxin concentrations and the repeated measurements from the stored eluates were high (r=0.789) for EU/m(3) PM(2.5). Since endotoxin was evaluated from the same set of filter halves, it is obvious that storage over three years did not substantially effect the correlation of the endotoxin content. Regarding the outliers from previous measurements unsymmetric endotoxin spots on one out of 48 filter halves could be determined. Apart from this we conclude that the endotoxin is homogenously distributed on the filter halves and that endotoxin levels, which were repeatedly measured from filters stored over three years, could be determined validly. 相似文献
1000.