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101.
Eggenberger-Solorzano L Niebuhr SE Acuff GR Dickson JS 《Journal of food protection》2002,65(8):1248-1252
Pork skin and muscle tissue were washed with water at temperatures from 25 to 80 degrees C. Water temperatures of 65 and 80 degrees C resulted in greater population reductions of Enterobacteriaceae on pork muscle tissue than lower water temperatures. There was no observable effect of water temperature on population reductions of Enterobacteriaceae on pork skin. Water temperatures of 55, 65, and 80 degrees C reduced the populations of Enterobacteriaceae on inoculated scalded carcasses processed in a university abattoir by 1 to 1.5 log/cm2. Following the water wash with an organic acid rinse resulted in further numerical reductions in populations, although these were not statistically different from the water wash alone. The jowls of both scalded and skinned carcasses processed in a commercial establishment were directly inoculated with a fecal material slurry and then processed with organic acid rinsing only, hot water washing only, or a combination of hot water washing followed by organic acid rinsing. The hot water and acid treatment reduced the populations of mesophilic aerobic bacteria and Escherichia coli by approximately 2 log cycles on both scalded and skinned hog carcasses. The combined treatment resulted in 60% of the scalded carcasses and 40% of the skinned carcasses with undetectable levels of E. coli after direct fecal inoculation of the carcasses. Hot water washing followed by organic acid rinsing can significantly improve the microbiological quality of pork carcasses. 相似文献
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104.
To speed up similarity based searches many indexing techniques have been proposed in order to address the problem of efficiency. However, most of the proposed techniques do not admit fast insertion of new elements once the index is built. The main effect is that changes in the environment are very costly to be taken into account.In this work, we propose a new technique to allow fast insertions of elements in a family of static tree-based indexes. Unlike other techniques, the resulting index is exactly equal to the index that would be obtained by building it from scratch. Therefore there is no performance degradation in search time.We show that the expected number of distance computations (and the average time complexity) is bounded by a function that grows with log2(n) where n is the size of the database.In order to check the correctness of our approach some experiments with artificial and real data are carried out. 相似文献
105.
Ricardo García Elena Verdú Luisa M. Regueras Juan P. de Castro María J. Verdú 《Expert systems with applications》2013,40(10):4096-4105
Web mapping has become a popular way of distributing interactive digital maps over the internet. Instead of dynamically generating map images on the fly, those can be pre-generated and served from a server-side cache for faster retrieval. However, these caches can grow unmanageably in size when the cartography covers mid to large areas for multiple rendering scales. This forces modest organizations to use partial caches containing just a subset of the total tiles, and makes their services less attractive than other mapping services like Google Maps or Microsoft Bing Maps. This work proposes a neural-network-based intelligent system that predicts which areas are likely to be requested in the future from a catalog of geographic features and a short history of past requests. These priority regions can be used by a tile prefetching policy to achieve an optimal population of the cache. Neural networks are trained and validated using supervised learning with real data-sets from a public nation-wide web map service. Trace-driven simulations demonstrate that accurate long-term predictions, up to 90% in terms of cache-hit ratio, can be obtained with the proposed model by prefetching a low fraction, only the 20% of the total tiles, and with a short training period. 相似文献
106.
Ieva Raudoniūtė Jordi Rovira Petras Rimantas Venskutonis Jonas Damašius María Dolores Rivero‐Pérez María Luisa González‐SanJosé 《International Journal of Food Science & Technology》2011,46(5):935-943
The present study characterises garden strawberry leaf extract and reports its effect on shelf life and quality characteristics of fish oil. Radical scavenging capacity of the extract in DPPH? and ABTS?+ assays was equivalent to 1207 and 1579 μmol g?1 of trolox equivalents, respectively, total phenolic content was 257 mg g?1 of gallic acid equivalents. Phenolic and volatile constituents were analysed by liquid chromatography/mass spectrometry (LC/MS) and gas chromatography/mass spectrometry (GC/MS). The extract was added to fish oil and its oxidation was followed during 42 days: peroxide, p‐anisidine values and hexanal concentration were lower in the samples with extract, particularly at the end of storage. The effect of extract on fatty acid composition was not significant, however the changes in the percentages of some individual acids were observed. Fish oil containing 5% of extract had lower levels of lipid oxidation in comparison to other samples. The results indicate that strawberry leaves could be a potential source of natural antioxidants. 相似文献
107.
Continuity as the mathematical tool in the creation of architectural forms is known as morphocontinuity. In the present work,
we explain how morphocontinuity appears on the work of Eero Saarinen and discuss its correspondence with its environmental
(physical, social and cultural) contexts. 相似文献
108.
The data from the project “Conviver,” launched in 2006 in Belo Horizonte (Brazil), provides a unique opportunity to study illegal electricity connections. Based on an original dataset of 15,279 low-income households, this paper studies the incidence and determinants of illegality in the context of low-income urban favelas. The probability of engaging in illegal behavior is explained not just by low income, but by a combination of concurring factors: sub-standard energy provision and equipment; inefficient/incorrect use of domestic electric appliances and running an informal in-house business. These recurrent issues in the urban favelas aggravate a sense of exclusion from growth, which is generally recognized as a trigger of illegality. The impact of energy demand on energy-related illegality is carefully analyzed, and different empirical strategies adopted to circumvent some simultaneity problem between both decision processes. The effectiveness of consumption-based energy subsidies is also explored. In spite of some contrary arguments in the literature, in the context of peri-urban slums, such measures may exert a positive impact in mitigating illegal access and use of energy. Effectiveness will be enhanced by accompanying measures such as: perceivable improvements of equipment, metering and maintenance, promotion of beneficiaries’ awareness of energy usage, and energy-saving behaviors. 相似文献
109.
Luisa María Gil-Martín Enrique Hernández-Montes Mark Aschheim 《Structural and Multidisciplinary Optimization》2010,41(6):979-987
The ultimate strength design of reinforced concrete members under flexure and axial loads is well known, with solutions dating back to the 1950s. There is little motivation for engineers to change solution approaches in the absence of a clear benefit, particularly given that current solution approaches are well-known and do not raise controversy. Recently, a different solution approach has been presented in the form of Reinforcement Sizing Diagrams and Optimal Domains, but applications to rectangular sections were limited and thus the approach has been mainly of academic or theoretical interest. This paper presents an application to circular sections, which allow the advantages to be realized in the commonly encountered situation of retaining walls supported by circular section piers. Using the approach presented herein, longitudinal reinforcement can be reduced up to 50% compared with traditional designs, allowing significant financial savings while also reducing the greenhouse gas emissions associated with the reinforcement component of reinforced concrete construction. 相似文献
110.
Simone Mancin Claudio Zilio Alberto Cavallini Luisa Rossetto 《International Journal of Heat and Mass Transfer》2010,53(15-16):3121-3130
This paper aims at investigating experimentally the pressure drop during air flow in six different aluminum open-cell foam samples with different number of pores per inch (PPI) and different porosity under a wide range of air mass flow rate. Three imposed heat fluxes are considered for each foam sample. The collected pressure drop data are analysed with reference to models available in the literature. A new simple pressure drop model, based on present data, has then been developed. The consistency of the proposed model is finally checked by comparison to data available in the literature from different laboratories. 相似文献