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91.
Asbj?rn Haaning Nielsen Thorkild Hvitved-Jacobsen Jes Vollertsen 《Canadian Metallurgical Quarterly》2007,133(6):655-658
Effects of iron on the kinetics and stoichiometry of aerobic chemical sulfide oxidation in wastewater from two different sites were studied at pH 8 and 20°C. Iron(III) chloride was added to the wastewater in concentrations of up to 20?g?Fe?m?3. The rate of aerobic chemical sulfide oxidation increased linearly with the iron(III) additions resulting in equal effects with wastewater from the two sites. Despite the significant effect of the iron(III) additions, the background concentrations of iron cannot explain the significant temporal and spatial variability of aerobic chemical sulfide oxidation kinetics reported in this study and in the literature. In this respect, other metals are probably also important. In addition to the impacts on the oxidation kinetics, the iron(III) additions resulted in a change of the oxidation stoichiometry. With increasing amounts of iron(III) added to the wastewater, less dissolved oxygen was required for the sulfide oxidation. 相似文献
92.
This paper estimates response surface coefficients for a large range of quantiles of the cross-sectionally augmented IPS (CIPS) test of Pesaran (2007), for different specifications of the deterministic components. An Excel programme is available to calculate the P value associated with a CIPS test statistic. 相似文献
93.
Damaris Fuentes-Lorenzo Norberto Fernández Jesús A. Fisteus Luis Sánchez 《Expert systems with applications》2013,40(6):2287-2296
Traditional search engines have become the most useful tools to search the World Wide Web. Even though they are good for certain search tasks, they may be less effective for others, such as satisfying ambiguous or synonym queries. In this paper, we propose an algorithm that, with the help of Wikipedia and collaborative semantic annotations, improves the quality of web search engines in the ranking of returned results. Our work is supported by (1) the logs generated after query searching, (2) semantic annotations of queries and (3) semantic annotations of web pages. The algorithm makes use of this information to elaborate an appropriate ranking. To validate our approach we have implemented a system that can apply the algorithm to a particular search engine. Evaluation results show that the number of relevant web resources obtained after executing a query with the algorithm is higher than the one obtained without it. 相似文献
94.
Stine Rønholt Patrizia Buldo Kell Mortensen Ulf Andersen Jes C. Knudsen Lars Wiking 《Journal of dairy science》2014
Milk fat exists as globules in its natural state in milk. The potential of using globular fat to modulate the rheological properties and crystallization behavior in butter-like emulsions was studied in the present work. We conducted a comparative study of butter-like emulsions, with a fat phase consisting of 0, 10, 25, 50, or 100% anhydrous milk fat (AMF), the remaining fat being butter grains, and all samples containing 20% water, to obtain systematic variation in the ratio of globular fat. All emulsions were studied over 4 wk of storage at 5°C. By combining small and large deformation rheology, we conducted a detailed characterization of the rheological behavior of butter-like emulsions. We applied differential scanning calorimetry to monitor thermal behavior, confocal laser scanning microscopy for microstructural analysis, and low-field pulsed nuclear magnetic resonance spectrometry to measure solid fat content. By combining these techniques, we determined that increasing the fraction of globular fat (by mixing with butter grains) decreases the hardness of butter-like emulsions up to an order of magnitude at d 1. However, no difference was observed in thermal behavior as a function of butter grain content, as all emulsions containing butter grains revealed 2 endothermal peaks corresponding to the high (32.7°C ± 0.6) and medium (14.6°C ± 0.1) melting fractions of fatty acids. In terms of microstructure, decreasing the amount of butter grains in the emulsions resulted in formation of a denser fat crystal network, corresponding to increased hardness. Moreover, microstructural analysis revealed that the presence of butter grains resulted in faster formation of a continuous fat crystal network compared with the 100% AMF sample, which was dominated by crystal clusters surrounded by liquid oil. During storage, hardness remained stable and no changes in thermal behavior were observed, despite an increase in solid fat content of up to 5%. After 28 d of storage, we observed no difference in either microstructural or rheological properties, indicating that formation of primary bonds occurs primarily within the first day of storage. The rheological behavior of butter-like emulsions is not determined solely by hardness, but also by stiffness related to secondary bonds within the fat crystal network. The complex rheological behavior of milk fat-based emulsions is better characterized using multiple parameters. 相似文献
95.
Escobar Juan José Ortega Julio Díaz Antonio F. González Jesús Damas Miguel 《The Journal of supercomputing》2019,75(7):3397-3425
The Journal of Supercomputing - Present heterogeneous architectures interconnect nodes including multiple multi-core microprocessors and accelerators that allow different strategies to accelerate... 相似文献
96.
Ana Isabel Rodríguez-Bernaldo De Quirós Julia López-Hernández María José González-Castro Carlos De la Cruz-García Jesús Simal-Lozano 《European Food Research and Technology》2000,210(3):226-230
The effects of four culinary treatments (steaming and boiling in a covered pot, a pressure cooker or a microwave oven) on
the volatile component profile of green beans were evaluated. Volatile compounds in raw and cooked beans were analysed by
means of dynamic headspace sampling onto an adsorbent, followed by microwave desorption into a gas chromatograph equipped
with a mass spectrometric detector. Twenty-seven compounds were identified, including alcohols, aldehydes, ketones, esters,
terpenes, sulphur compounds and alkenes. All of the thermal treatments caused important changes in the volatile compound profile
in particular an increase in carbonyl compounds and a decrease in alcohol compounds, most notably in the case of the covered
pot. It is concluded that the change in aroma during the cooking of green beans depends on compounds from lipid oxidation
as well as compounds from other types of reactions, for instance the Strecker degradation.
Received: 8 March 1999 / Revised version: 23 April 1999 相似文献
97.
Jesús?MarínEmail author 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(4):683-698
Ruggedness has a strong influence on the performance of algorithms, but it has been barely studied in real-coded optimization,
mainly because of the difficulty of isolating it from a number of involved topological properties. In this paper, we propose
a framework consisting of increasing ruggedness function sets built by a mechanism which generates multiple funnels. This
mechanism introduces different levels of sinusoidal distortion which can be controlled to isolate the singular influence of
some related features. Some commonly used measures of ruggedness have been applied to analyze these sets of functions, and
a numerical study to compare the performance of some representative algorithms has been carried out. The results confirm that
ruggedness has an influence on the performance of the algorithm, proving that it depends on the multi-funnel structure and
peak features, such as height and relative size of the global peak, and not on the number of peaks. 相似文献
98.
Vincent Léchappé Jesús De Léon Emmanuel Moulay Franck Plestan Alain Glumineau 《国际强度与非线性控制杂志
》2018,28(6):2356-2368
》2018,28(6):2356-2368
This paper deals with the problem of state and delay estimation for SISO nonlinear systems with an unknown time‐varying delay in the input. The main idea is to approximate the delayed input by using Taylor's theorem and to create an extended system with the delay as part of the extended state. Then, the construction of an observer is proposed to estimate both state and delay. The results are illustrated by simulations. 相似文献
99.
Nicolette Czarnievicz Dr. Maria Grazia Rubanu Maialen Iturralde Dr. Jesús Albarran-Velo Dr. Eleftheria Diamanti Prof. Vicente Gotor-Fernandez Dr. Maciej Skolimowski Prof. Fernando López-Gallego 《Chembiochem : a European journal of chemical biology》2023,24(2):e202200614
The development of methods to engineer and immobilize amine transaminases (ATAs) to improve their functionality and operational stability is gaining momentum. The quest for robust, fast, and easy-to-use methods to screen the activity of large collections of transaminases, is essential. This work presents a novel and multiplex fluorescence-based kinetic assay to assess ATA activity using 4-dimethylamino-1-naphthaldehyde as an amine acceptor. The developed assay allowed us to screen a battery of amine donors using free and immobilized ATAs from different microbial sources as biocatalysts. As a result, using chromatographic methods, 4-hydroxybenzylamine was identified as the best amine donor for the amination of 5-(hydroxymethyl)furfural. Finally, we adapted this method to determine the apparent Michaelis-Menten parameters of a model immobilized ATA at the microscopic (single-particle) level. Our studies promote the use of this multiplex, multidimensional assay to screen ATAs for further improvement. 相似文献
100.