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61.
Alberto Abad Anna Pompili Angela Costa Isabel Trancoso José Fonseca Gabriela Leal Luisa Farrajota Isabel P. Martins 《Computer Speech and Language》2013,27(6):1235-1248
One of the most common effects among aphasia patients is the difficulty to recall names or words. Typically, word retrieval problems can be treated through word naming therapeutic exercises. In fact, the frequency and the intensity of speech therapy are key factors in the recovery of lost communication functionalities. In this sense, speech and language technology can have a relevant contribution in the development of automatic therapy methods. In this work, we present an on-line system designed to behave as a virtual therapist incorporating automatic speech recognition technology that permits aphasia patients to perform word naming training exercises. We focus on the study of the automatic word naming detector module and on its utility for both global evaluation and treatment. For that purpose, a database consisting of word naming therapy sessions of aphasic Portuguese native speakers has been collected. In spite of the different patient characteristics and speech quality conditions of the collected data, encouraging results have been obtained thanks to a calibration method that makes use of the patients’ word naming ability to automatically adapt to the patients’ speech particularities. 相似文献
62.
Aerodynamic shape optimization of wind turbine blades using a Reynolds‐averaged Navier–Stokes model and an adjoint method 下载免费PDF全文
Computational fluid dynamics (CFD) is increasingly used to analyze wind turbines, and the next logical step is to develop CFD‐based optimization to enable further gains in performance and reduce model uncertainties. We present an aerodynamic shape optimization framework consisting of a Reynolds‐averaged Navier Stokes solver coupled to a numerical optimization algorithm, a geometry modeler, and a mesh perturbation algorithm. To efficiently handle the large number of design variables, we use a gradient‐based optimization technique together with an adjoint method for computing the gradients of the torque coefficient with respect to the design variables. To demonstrate the effectiveness of the proposed approach, we maximize the torque of the NREL VI wind turbine blade with respect to pitch, twist, and airfoil shape design variables while constraining the blade thickness. We present a series of optimization cases with increasing number of variables, both for a single wind speed and for multiple wind speeds. For the optimization at a single wind speed performed with respect to all the design variables (1 pitch, 11 twist, and 240 airfoil shape variables), the torque coefficient increased by 22.4% relative to the NREL VI design. For the multiple‐speed optimization, the torque increased by an average of 22.1%. Depending on the CFD mesh size and number of design variables, the optimization time ranges from 2 to 24h when using 256 cores, which means that wind turbine designers can use this process routinely. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
63.
Front Cover: Photoactivatable Mussel‐Based Underwater Adhesive Proteins by an Expanded Genetic Code (ChemBioChem 18/2017) 下载免费PDF全文
Dr. Matthias Hauf Dr. Florian Richter Tobias Schneider Thomas Faidt Dr. Berta M. Martins Dr. Tobias Baumann Dr. Patrick Durkin Prof. Dr. Holger Dobbek Prof. Dr. Karin Jacobs Prof. Dr. Andreas Möglich Prof. Dr. Nediljko Budisa 《Chembiochem : a European journal of chemical biology》2017,18(18):1771-1771
64.
Characterization of a water-based paint for corrosion protection 总被引:1,自引:0,他引:1
Paula Dias Catarina Carneiro Luísa Andrade José Sousa João Machado Adélio Mendes 《Journal of Coatings Technology and Research》2012,9(3):365-374
Corrosion of steel rebars in reinforced concrete is one of the major problems in the construction industry. Carbonation reactions
of concrete with carbon dioxide and, mainly, the chloride salts action are the main causes responsible for concrete degradation.
Protective coatings help to improve the durability of concrete structures by acting as a physical barrier against the corrosion
agents. Waterborne paints are usually used for concrete protection rather than solvent-based paints since they are less pollutant.
The aim of this work is to investigate the influence of the pore size and porosity on the permeability of the paints films
toward sodium chloride. Three characterization methods from membrane science were implemented to characterize paint coatings.
The time-lag method was used to determine the permeability toward the sodium chloride and toward helium and argon, these for
approximately 100% relative humidity. From the seven waterborne paints formulated, only one was found to be suitable for surface
protection of reinforced concrete, since its permeability toward NaCl was smaller than 10−14 m2 s−1, the threshold value required by National Laboratory of Civil Engineering (LNEC) in Portugal. For the formulated paints,
it was observed that the average pore size correlates well with the permeability toward sodium chloride. This is an important
result since obtaining the permeability toward sodium chloride of corrosion protective paints is very time consuming, while
the average pore size can be obtained in a much shorter time. 相似文献
65.
The present study evaluates the role of the microstructure in the static and dynamic mechanical behavior of as-cast Al7075 alloy promoted by ultrasonic treatment (US) during solidification. The characterization of samples revealed that US treatment promoted grain and intermetallics refinement, changed the shape of the intermetallic phases (equilibrium phases of soluble M and/or T (Al, Cu, Mg, Zn) and their insoluble Al-Cu-Fe compounds) and lead to their uniform distribution along the grain boundaries. Consequently, the mechanical properties and damping capacity above critical strain values were enhanced by comparison with values obtained for castings produced without US vibration. This results suggest that the grain and secondary phases refinement by US can be a promising solution to process materials to obtain high damping and high strength characteristics. 相似文献
66.
Marcos Eduardo Valle Raul Ambrozio Valente 《Journal of Mathematical Imaging and Vision》2017,57(2):183-201
Mathematical morphology is a theory with applications in image processing and analysis. This paper presents a quantale-based approach to color morphology based on the CIELab color space in spherical coordinates. The novel morphological operations take into account the perceptual difference between color elements by using a distance-based ordering scheme. Furthermore, the novel approach allows for the use of non-flat structuring elements. An illustrative example reveals that non-flat dilations and erosions may preserve more features of a color image than their corresponding flat operations. Furthermore, the novel non-flat morphological operators yielded promising results on experiments concerning the detection of the boundaries of objects on color images. 相似文献
67.
Ângela Fernandes João C. M. Barreira Amilcar L. Antonio M. Beatriz P. P. Oliveira Anabela Martins Isabel C. F. R. Ferreira 《Food and Bioprocess Technology》2014,7(6):1606-1617
Mushrooms are very perishable foods due to their high susceptibility to moisture loss, changes in color and texture, or microbiological spoilage. Drying is considered as the most appropriate method to prevent these alterations, but it has some limitations, such as shrinkage, enzymatic and non-enzymatic browning reactions, and oxidation of lipids and vitamins. According to previous studies, irradiation might effectively attenuate the undesirable changes caused by drying process, ensuring also higher shelf-life of mushrooms and their decontamination. Electron-beam irradiation presents some technological advantages, since it allows higher dose rates and the possibility to be used in most foods/or thin products in a short period. Herein, the combined effects of electron-beam irradiation (0, 0.5, 1 and 6 kGy) and storage time (0, 6 and 12 months) were evaluated by measuring changes in nutritional parameters, namely, free sugars, tocopherols, fatty acids and antioxidant activity. As indicated by linear discriminant analysis, storage time had a higher effect on all the evaluated parameters, except fatty acids, which suffer significant changes with both factors. Overall, the obtained results indicate that electron-beam irradiation might be considered as a suitable technique, allowing long-lasting conservation periods while reducing changes induced by drying treatment. 相似文献
68.
Natalia Mattar Cantagalli Kelly Cristina Martins Faeda Rafael Witter Dias Pais Ana Maria Matildes dos Santos Wilmar Barbosa Ferraz 《能源与动力工程:英文版》2014,(8):1409-1414
Nuclear fuel based on uranium metal alloys is utilized in research and test reactors. For the purpose of the reduction of fuel enrichment, high densities of uranium-235 in this kind of fuel are needed. This can be achieved when uranium alloys are used containing elements such as Zr, Mo and Nb. The construction of fuel element with high-uranium density requires materials with low cross sections for neutron absorption, stability under irradiation and absence of the chemical interactions between the fuel and cladding elements. In case of U-Zr-Nb alloys, Zry (zircaloy) cladding is a better option due to the fact that they have a higher chemical compatibility when compared with the use of aluminum alloys. This study aims to develop plate type nuclear fuel using the U-2.5Zr-7.5Nb alloy dispersed in Zry. Powders of this uranium based alloy and Zry were obtained by hydriding-dehydriding process. These powders were homogenized, compacted in pellet that was sandwiched in plates and frame of Zry. This assembly was hot rolled forming the dispersion fuel miniplate. 相似文献
69.
Comprehensive design schemes and specifications have progressively shaped Master-Planned Communities (MPCs). The market largely predetermines these outcomes, with background input from communities. Therefore, this paper endeavours to define the fundamental structures that generate differences between market actors and residents within the North Lakes MPC. This study employs ‘habitus theory’, which is a sociological phenomenon describing the divergence of personal outlooks and expertise. The application of this theory is thus illustrative of the evolution of distinct observations within MPCs. Contemporary studies have under-researched these inherent gaps between communities, authorities, and critics, and these frictions could be exacerbated within restrictive developmental contexts. Epistemic and objectified content analyses collated over many years and sources will uncover the underlying differences between the relevant groups. These analyses will enable the progression of a framework for understanding power relation biases and how reflexivity can enhance current consultative methods. 相似文献
70.
Vicente Pacheco Raul Cardoso-Gil Lorenzo Tepech-Carrillo Yuri Grin 《Corrosion Science》2011,(7):2368-2373
The corrosion of thermoelectric clathrates α- and β-Eu8Ga16−xGe30+x is studied under static air (DSC/TG) up to 650 °C. Oxidation product layers with thicknesses of 10.5 μm (α-Eu8Ga16−xGe30+x) and 4.5 μm (β-Eu8Ga16−xGe30+x) are formed. The oxidation begins at 360 and 380 °C, respectively. XRD pattern of the β-Eu8Ga16−xGe30+x oxidized layer shows Ge and four Eu2O3 reflections; while α-Eu8Ga16−xGe30+x data (sample crushed and grinded) shows α-Eu8Ga16−xGe30+x reflections (majority phase), two EuGa2±xGe4?x strongest reflections and Ge (minority phases). These results indicate the amount of oxides is very small or they are amorphous. High temperature powder XRD measurements on α-Eu8Ga16−xGe30+x under air confirm the oxidation onset temperature determined in DSC studies. 相似文献