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Intrauterine programming of lipid metabolic alterations in the heart of the offspring of diabetic rats is prevented by maternal diets enriched in olive oil 下载免费PDF全文
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Teresa Díaz-Faes López Alfonso Fernández González ángel Del Reguero María Matos Marta E Díaz-García Rosana Badía-Laí?o 《Science and Technology of Advanced Materials》2015,16(5)
Silica nanoparticles (SiO2 NPs) synthesized by the sol–gel approach were engineered for size and surface properties by grafting hydrophobic chains to prevent their aggregation and facilitate their contact with the phase boundary, thus improving their dispersibility in lubricant base oils. The surface modification was performed by covalent binding of long chain alkyl functionalities using lauric acid and decanoyl chloride to the SiO2 NP surface. The hybrid SiO2 NPs were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, simultaneous differential thermal analysis, nuclear magnetic resonance and dynamic light scattering, while their dispersion in two base oils was studied by static multiple light scattering at low (0.01% w/v) and high (0.50%w/v) concentrations. The nature of the functional layer and the functionalization degree seemed to be directly involved in the stability of the suspensions. The potential use of the functional SiO2 NPs as lubricant additives in base oils, specially designed for being used in hydraulic circuits, has been outlined by analyzing the tribological properties of the dispersions. The dendritic structure of the external layer played a key role in the tribological characteristics of the material by reducing the friction coefficient and wear. These nanoparticles reduce drastically the waste of energy in friction processes and are more environmentally friendly than other additives. 相似文献
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Spanish cheese screening and selection of lactic acid bacteria with high gamma-aminobutyric acid production 总被引:1,自引:0,他引:1
Gamma-aminobutyric acid (GABA) is a non-protein four-carbon amino acid which is considered a bioactive component known for its physiological functions, including a regulator of blood pressure, neurotransmitter, diuretic and anti-stress effects. Its use in foods might confer health benefits. Microorganisms such as yeast, fungi or bacteria can produce GABA naturally. Among them, the lactic acid bacteria are being studied for the potential development of fermented foods because their physiological activities and their designation of generally recognized as safe (GRAS). The objective of this study was to evaluate the GABA-production capacity in a whole wheat flour medium of lactic acid bacteria strains that showed a high conversion of glutamic acid to GABA in a screening conducted in 58 Spanish artisanal cheeses. Synthesis of GABA by these strains in a non-optimized whole wheat flour in water solution (1:5) was quantified by High-Performance Liquid Chromatography. The 4 strains showing the highest GABA production were genotypically and phenotypically characterized. Results indicated an interesting fermentative variability between strains. The addition of these isolated lactic acid strains in fermented food products could allow a potentially functional food for regulating hypertension. 相似文献
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María Pérez‐Juan Carolina E. Realini Marta Barahona Maria Victoria Sarriés Maria del Mar Campo María José Beriain Mauro Vitale Marta Gil Pere Albertí 《Journal of food science》2014,79(11):S2377-S2382
The effect of different animal diets supplemented with linseed (source of omega‐3 fatty acids: n‐3) and/or conjugated linoleic acid (CON: control, LIN: 10% linseed, CLA: 2% conjugated linoleic acid, LINCLA: 10% linseed plus 2% CLA) on consumer liking of beef aged for 7 or 21 d was assessed in 3 Spanish cities. Overall, tenderness, juiciness, and flavor liking of beef were evaluated by consumers (n = 720) using 9‐point scales. Hedonic scores assigned by consumers did not differ (P > 0.05) for beef from animals fed the different diets and aged for 7 or 21 d. Consumer scores showed an increasing trend in beef liking with aging time. Consumers from Pamplona assigned lower (P < 0.05) hedonic scores for beef liking than consumers from Barcelona and Zaragoza. Linseed and/or CLA can be fed to improve the fatty acid profile in beef with minimal impact on consumer liking. Consumer ratings seem to depend on regional tastes and preferences. 相似文献
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Challenges to Manage the Risk of Water Scarcity and Climate Change in the Mediterranean 总被引:6,自引:3,他引:3
Ana Iglesias Luis Garrote Francisco Flores Marta Moneo 《Water Resources Management》2007,21(5):775-788
The Mediterranean region is undergoing rapid local and global social and environmental changes. All indicators point to an
increase in environmental and water scarcity problems with negative implications towards current and future sustainability.
Water management in Mediterranean countries is challenged these pressures and needs to evolve to reach the target of increasing
population with reliable access to freshwater established by the Millennium Development Goals. This paper first reviews and
evaluates current and future social and environmental pressures on water resources, including climate change. The results
show that pressures are not homogeneous across the region and sectors of water use. Second the paper evaluates the adaptation
strategies to cope with water scarcity, including technology, use of strategic groundwater, and management. Finally, the paper
proposes a framework for managing the risk of water scarcity based on preparedness rather than a crisis approach. The importance
of local management at the basin level is emphasized, but the potential benefits depend on the appropriate multi-institutional
and multi-stakeholder coordination. 相似文献