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991.
BF Meyers RS Sundaresan T Guthrie JD Cooper GA Patterson 《Canadian Metallurgical Quarterly》1999,117(2):358-364
OBJECTIVE: The objective of this study was to assess the efficacy and safety of an alternative surgical incision for bilateral sequential lung transplantation. The vast majority of these operations worldwide have been performed through an anterolateral thoracosternotomy known as the "clamshell" incision. Recently, we have undertaken most of these operations through bilateral anterolateral thoracotomies without sternal division. METHODS: Our medical center performed 262 bilateral sequential single lung transplantations from 1989 to April 1998. Between July 1996 and April 1998 we performed 69 bilateral sequential single lung transplantations on 68 recipients with 52 transplantations being conducted without initial sternal division. We retrospectively reviewed the results of these operations to assess the safety of the altered exposure and the efficacy in avoiding sternal wound complications such as malunion, dehiscence, osteomyelitis, and migrating hardware. Comparison was made to a historical control group composed of the last 50 patients in whom the full clamshell incision was used. RESULTS: Of the 68 patients who underwent transplantations, 52 patients underwent the initial exploratory procedure without sternal division. Two patients required emergency sternal division for institution of cardiopulmonary bypass to control life-threatening bleeding. Eleven of 68 patients were placed on bypass electively to permit transplantation, and the lack of a sternotomy in 8 patients did not present an obstacle to ascending aortic and right atrial cannulation. There were no wound healing complications in the 50 patients for whom the sternum was left intact. In a historical control group of 50 patients who underwent transplantation with sternal division, 34% experienced morbidity or mild disability as a direct result of poor sternal healing. CONCLUSIONS: We conclude that bilateral anterolateral thoracotomy without sternal division is a safe approach that allows adequate exposure without the risk of commonly observed problems with sternal healing. 相似文献
992.
da Silva Silma Francielle Silva Felipe Anchieta e de Souza Ana Paula Martins Rodrigues Thenner Silva Teixeira Róbson Ricardo 《Journal of Materials Science》2022,57(3):1669-1688
Journal of Materials Science - The present investigation describes the preparation of a sodium niobate nanostructured material and the application of it as catalyst in condensation reactions.... 相似文献
993.
Teixeira Elizabeth C. da Silva Victor E. L. Fabré Nidia N. Batista Vandick S. 《Scientometrics》2020,122(1):591-606
Scientometrics - Marine shrimp fishing is an economic activity of global importance due to its high profitability, but it also presents several environmental and socioeconomic problems. In a... 相似文献
994.
995.
Glass samples were tested for use in high-dose dosimetry in radiation processing. The main dosimetric characteristics were determined: lower detection threshold, reproducibility, response to gamma radiation of 60Co and thermal decay at room temperature, with the use of a densitometer, spectrophotometer and thermoluminescence reader. The results show that this kind of material could be useful for dosimetry in several applications of ionising radiation, taking into account its thermal fading. 相似文献
996.
Helm PA Diamond ML Semkin R Strachan WM Teixeira C Gregor D 《Environmental science & technology》2002,36(5):996-1003
Data collected over a 3-year study of a high arctic watershed and lake are used to understand the fate of organochlorine compounds (OCs) and form the basis of a mass balance contaminant fate model. The model uses the fugacity/aquivalence approach to describe OC dynamics between air, stream inflows and outflow, the water column, and surficial sediments. The steady-state model results indicate that stream inflows contributed from 96 to >99% of total chemical loadings, but 57-98% of total loadings were lost from the lake via the outlet, the percentage of which is controlled by the hydrologic regime of the high arctic lake. Conversely, only 0.4-3.4% of loadings were retained within the sediments due to the high export rate, minimal scavenging from the water column and low organic carbon fraction of the sediments. Using the unsteady-state model, which includes year-round processes, degradation was estimated to account for losses of 7-32% for the more persistent OCs and 42-50% for the less persistent OCs (alpha-HCH, gamma-HCH, and endosulfan I). If loadings were eliminated, water column concentrations would decline with half-lives <1 year for less persistent OCs and 1-2 years for the more persistent OCs, whereas the half-lives for OCs in sediment are 8-25 years. 相似文献
997.
André P. S. Pinto J. L. Teixeira A. J. Nolasco Pinto A. Almeida T. Morgado F. Pousa M. 《Photonic Network Communications》2002,4(1):63-72
In this paper, we assess the design and performances of a strictly non-blocking all-optical cross-connect demonstrator node for WDM wavelength path networks. The all-optical cross-connect (AOXC) prototype was experimentally tested in a small 2 x 2 WDM network with a STM-16 bit stream per channel. The single and cascaded performance of the AOXC was also simulated and its results were validated with the experimental ones. 相似文献
998.
Scientometrics - In forestry, the Pterocarpus genus is important for the wood industry as this is a tree that is highly valued for its timber. Biotechnological research on this tree genus therefore... 相似文献
999.
VE Archer AD Renzetti RS Doggett JQ Jarvis TV Colby 《Canadian Metallurgical Quarterly》1998,40(5):460-474
Many uranium miners have been disabled by and died of pulmonary fibrosis that was not recognized as an occupational disease. A review of animal studies, complications from whole body irradiation, pulmonary function, and mortality studies of uranium miners led us to suspect radiation-induced chronic diffuse interstitial fibrosis in miners who had inhaled excessive radon progeny. A selected group of uranium miners (22) with severe respiratory disease (but no rounded nodules in chest films) were studied. Lung tissue from five disclosed severe diffuse interstitial fibrosis, with "honeycomb lung" in all. Some also had small anthrasilicotic nodules and birefringent crystals. Although quartz crystals probably contributed, we concluded that the predominant injurious agent in these cases was alpha particles from radon progeny. This disease, after a long latent period, usually results in pulmonary hypertension, shortness of breath, and death by cardiopulmonary failure. 相似文献
1000.
Many persons with disabilities lack the fine motor coordination necessary to operate traditional keyboards. For these individuals, ambiguous (or reduced) keyboards offer an alternative access method. By placing multiple characters on each key, the size and accessibility of the individual keys can be enhanced without requiring a larger keyboard. Using statistical disambiguation algorithms to automatically interpret each keystroke, these systems can approach the keystroke efficiency (keystrokes per character) of conventional keyboards. Since the placement of characters on each key determines the effectiveness of these algorithms, several methods of optimizing keyboard arrangements have previously been proposed. This paper presents a new method for optimizing an arbitrary set of N characters over a collection of M keys. While earlier efforts relied upon approximations of keystroke efficiency, the proposed approach optimizes the arrangement under this exact performance measure. Applied to the canonical 26 characters on a nine-key "telephone keypad" problem, this method provides an improvement in efficiency of 2.5 percentage points over previously established layouts. Using only a minimum of calculations, the proposed technique operates quickly and efficiently, deriving optimal arrangements in a matter of seconds using a personal computer. The flexible method is applicable to arbitrary disambiguation algorithms, character sets, and languages. 相似文献