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991.
992.
Denis Doucet Andreas Ulbrich Ernest du Toit 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(24):3653-3660
Underground coal gasification (UCG) is a process that converts deep, un-mineable coal resources into syngas, which can then be converted into valuable end products such as electric power. This paper provides a summary of the options to combine UCG with electric power production and focuses on commercial-scale applications using a combined-cycle power plant including integration options and syngas cleanup steps. Simulation results for a UCG power plant with carbon capture are compared against the results for an equivalent Integrated Gasification Combined Cycle (IGCC) plant using the same feedstock. Relative capital cost savings for a UCG power plant are estimated based on published IGCC process unit costs. The UCG power plant with carbon capture is shown to provide a higher thermal efficiency, lower CO2 intensity, and lower capital cost than an equivalent IGCC plant. Finally, the potential of UCG as a method for producing cost-effective, low-emissions electrical power from deep coal is discussed and some of the challenges and opportunities are summarized. 相似文献
993.
Several regularities of the accumulation of vacuum arc metal macroparticles (MP) on the sample on repetitively pulsed biasing (105 Hz, 7 µs, ?0.5 kV to ?3.5 kV) have been investigated. It has been shown that the substrate temperature plays a very important role in controlling the MP amounts on the sample. A possibility to change the metal particle number density on the substrate in the range from 105/cm2 to 107/cm2, depending on bias pulse parameters, sample temperature, and ion plasma saturation current density, has been demonstrated. The shape of MPs and their adhesion to the substrate surface depends strongly on the MP energy balance in a high-voltage space charge sheath. 相似文献
994.
Duarte Liliana Rico; Martin Sophie; Brouillet Denis 《Canadian Metallurgical Quarterly》2008,40(4):211
The purpose of this study is to examine whether the way in which adults process animate and inanimate objects is impacted by the distinctiveness of the object and whether processing ability varies with age and with the quality of aging (e.g. normal aging versus pathological aging). We examined the perceptual functioning of young adults, elderly subjects and patients suffering from Alzheimer's disease. Generally, the results do not support the distributed model of conceptual representation. However, they do demonstrate that the ability to recognize objects by their distinctiveness is affected by normal and pathological aging. A gradual deterioration in the ability to correctly perceive animate objects was also observed as pathological aging progressed. These results, as well as our methods of assessing semantic memory, are discussed in terms of their theoretical and practical implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
The DIONISIO code describes most of the main phenomena occurring in a fuel rod during normal operation of a nuclear power reactor. Starting from the irradiation history, the code predicts the temperature distribution, elastic and plastic stress and strain, creep, swelling and densification, release of fission gases, caesium and iodine to the internal rod volume, gas mixing, pressure increase, irradiation growth of the cladding, development of an oxide layer on its surface and hydrogen uptake, restructuring and grain growth in the pellet.This work presents the model of Zircaloy fracture included in the code DIONISIO 1.0. The model of pellet-cladding mechanical interaction (PCMI) provides the forces caused by the solid-solid contact which add to the changing internal pressure and to the constant external pressure. Besides, the program evaluates the effects of a corrosive atmosphere (stress corrosion cracking, SCC) internal or external. With these data, the code calculates the J integral around the tip of an initiated crack, and proceeds to analyze, according to the quantity of corrosive substance dissolved and the cladding stress field, if the crack remains unchanged, if it grows due to the I-SCC mechanism, or if propagation is ductile, following the R curve of the material.Results corresponding to different PHWR and PWR reactors are presented and compared with code results. In particular, good agreement is obtained in the simulation of MOX experiments, where the cladding failed due to propagation of cracks originated in SCC. 相似文献
996.
Alain Favre‐Réguillon Denis Murat Gérard Cote Micheline Draye 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(10):1497-1501
BACKGROUND: Cloud point extraction (CPE) is an attractive alternative to solvent extraction. However, comparisons between both techniques are lacking. In this paper, the extraction of uranium(VI) using 8‐hydroxyquinoline (HQ) as chelating agent was studied by CPE using Triton X‐114 as non‐ionic surfactant and by solvent extraction using CHCl3 as diluent. RESULTS: Using CPE, a quantitative extraction was observed for pH higher than 4.5 with a HQ/U ratio of 10. Using solvent extraction an increase in the HQ/U ratio up to 50 is necessary to obtain a near quantitative extraction. Both extraction systems were then compared with respect to the nature of extracted species, and the extraction constants determined using log‐log analysis of the extraction data. In the solvent extraction system, the extracted species were identified as UO2Q2 and the corresponding extraction constant was found to be log kex = ? 3.6 ± 0.2 on the molar scale. Considering that UO2Q2 is also the extracted species in CPE, a slightly higher extraction constant, i.e. log kex = ? 2.5 ± 0.3, was found. CONCLUSION: Such a small difference in favour of the CPE system may arise from the combination of various phenomena, including effects of temperature and effects of ‘extractant environment’. However, a change in the nature of the extracted species, namely from UO2Q2 in the solvent extraction system to the formation of adducts, i.e. UO2Q2(HQ) and UO2Q2(HQ)2 in the CPE system, due to higher HQ concentration in the surfactant‐rich phase compared with chloroform, cannot be precluded, but requires confirmation. Copyright © 2012 Society of Chemical Industry 相似文献
997.
Brouillet Thibaut; Ferrier Laurent P.; Grosselin Anne; Brouillet Denis 《Canadian Metallurgical Quarterly》2011,11(5):1202
Recent results from Cannon, Hayes, and Tipper (2010) have established that the Action Compatibility Effect (ACE) is hedonically marked and elicits a genuine positive reaction. In this work, we aim to show that the hedonic marking of the ACE has incidental consequences on affective judgment. For this, we used the affective priming paradigm principle (for a review, see Musch & Klauer, 2003): participants have to respond, as quickly as they can, regarding the pleasantness or unpleasantness character of a target word. In the priming phase, we do not present an affective stimulus; however, we present two different graspable objects, one after the other. The handles of the graspable objects are shown either both on the same side (i.e., perceptual action compatibility) or not (i.e., perceptual action incompatibility). In addition, the orientation of the handles of the objects are either compatible (i.e., action compatibility) or not (i.e., action compatibility) with the response hand used for the word evaluation. Consistent with our hypothesis, participants responded faster to positive words after perceptual action compatibility and action compatibility (thus demonstrating the ACE) than after incompatibility conditions. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
998.
Elif Tosun Denis Zorin 《Computer Aided Geometric Design》2011,28(1):1-22
We present a manifold-based surface construction extending the C∞ construction of Ying and Zorin (2004). Our surfaces allow for piecewise-smooth boundaries and have an improved derivative and visual behavior. Their degree of smoothness can be controlled by the user. Two-flexibility of our surface construction is confirmed numerically for a range of local mesh configurations. 相似文献
999.
The binary relation framework has been shown to be applicable to many real-life preference handling scenarios. Here we study preference contraction: the problem of discarding selected preferences. We argue that the property of minimality and the preservation of strict partial orders are crucial for contractions. Contractions can be further constrained by specifying which preferences should be protected. We consider preference relations that are finite or finitely representable using preference formulas. We present algorithms for computing minimal and preference-protecting minimal contractions for finite as well as finitely representable preference relations. We study relationships between preference change in the binary relation framework and belief change in the belief revision theory. We evaluate the proposed algorithms experimentally and present the results. 相似文献
1000.
Mathieu Renouf Philippe A. Guy Cynthia Marmet Anne‐Lise Fraering Karin Longet Julie Moulin Marc Enslen Denis Barron Fabiola Dionisi Christophe Cavin Gary Williamson Heike Steiling 《Molecular nutrition & food research》2010,54(6):760-766
Previous studies on coffee examined absorption of phenolic acids (PA) in the small intestine, but not the contribution of the colon to absorption. Nine healthy volunteers ingested instant soluble coffee (~335 mg total chlorogenic acids (CGAs)) in water. Blood samples were taken over 12 h, and at 24 h to assess return to baseline. Many previous studies, which used glucuronidase and sulfatase, measured only PA and did not rigorously assess CGAs. To improve this, plasma samples were analyzed after full hydrolysis by chlorogenate esterase, glucuronidase and sulfatase to release aglycone equivalents of PA followed by liquid–liquid extraction and ESI‐LC‐ESI‐MS/MS detection. Ferulic, caffeic and isoferulic acid equivalents appeared rapidly in plasma, peaking at 1–2 h. Dihydrocaffeic and dihydroferulic acids appeared in plasma 6–8 h after ingestion (Tmax=8–12 h). Substantial variability in maximum plasma concentration and Tmax was also observed between individuals. This study confirms that the small intestine is a significant site for absorption of PA, but shows for the first time that the colon/microflora play the major role in absorption and metabolism of CGAs and PA from coffee. 相似文献