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101.
Propolis presents several health benefits due to the presence of bioactive compounds, mainly phenolic compounds; however, its application in food is limited due to undesirable odor and low water solubility. The bioactive compounds are usually susceptible to degradation by exposure to light, heat, or oxygen or by interaction with other compounds, which may limit its biological activity. The study aimed the propolis extract microencapsulation using rice, pea, soybean, and ovoalbumin proteins as wall material by spray drying and to analyze their in vitro digestion. The propolis extract presented a high concentration of apigenin. Encapsulation efficiency was greater than 70%, and it was maintained the antioxidant activity of propolis (88% inhibition of DPPH for propolis extract and >?73% for the microparticles). The DSC, ATR-FTIR, and X-ray diffraction techniques confirmed the encapsulation. The microparticles showed different shapes, sizes, and physical characteristics. The microparticles encapsulated with pea protein could be used in formulations of Minas Frescal cheese due to the controlled released, whereas the other microparticles could be used in pudding formulations.  相似文献   
102.
We propose an exact mathematical mapping that can be useful for making an analog quantum simulator that uses ion-based systems to realize the many-body electron–electron Coulomb interaction of an electron gas. This exact mathematical mapping allows us to deal with a system that is difficult to solve and control using a potentially more experimentally feasible setup. We show that ions can efficiently simulate electronic Coulomb interactions by using a unitary dilatation transform. The transformation does not need to be physically implemented if only the energy spectrum is desired, eliminating the complexity overhead. This proposal works in any number of dimensions and could be used to simulate different topological phases of electrons in graphene-like structures, by using ions confined in honeycomb lattices.  相似文献   
103.
Computational results were obtained for turbulent flow and heat transfer in curved pipes, representative of helically coiled heat exchangers. Following a grid refinement study, grid independent predictions from alternative turbulence models (k?, SST kω and RSM–ω) were compared with DNS results and experimental pressure drop and heat transfer data. Using the SST kω and RSM–ω models, pressure drop results were in excellent agreement with literature data and the Ito correlation. For heat transfer, the literature is not comparably complete or accurate, but a satisfactory agreement was obtained in the range of available data. Unsatisfactory results, both for pressure drop and heat transfer, were given by the k? model with wall functions. Following the validation study, the RSM–ω model was used to compute friction coefficients and Nusselt numbers in the range Re = 1.4·104–8·104, Pr = 0.7–5.6 and δ (coil curvature) = 3·10?3–0.3. Power-law correlations were found unsuitable to fit the Re-, Pr- and δ-dependence of the Nusselt number, while the use of a properly formulated momentum-heat transfer analogy collapsed all results with high accuracy.  相似文献   
104.
A smart card is a tamper-resistant miniature computer that performs some basic computations on input a secret information. So far, smart cards have been widely used for securing many digital transactions (e.g., pay television, ATM machines).We focus on the implementation of operating system security services leveraging on smart cards. This very challenging feature allows one to personalize some functionalities of the operating system by simply changing a smart card. Current solutions for integrating smart card features in operating system services require at least a partial execution of some of the operating system functionalities at “user level”. Unfortunately, system functionalities built on top of components lying at both kernel and user levels may negatively affect the overall system security, due to the introduction of multiple points of failure.In this work, we present the design and implementation of SmartK: a framework that integrates features of smart cards uniquely in the Linux kernel. In order to validate our approach, we propose a host of enhancements to the Linux operating system built on top of SmartK: 1) in-kernel clients' authentication with Kerberos; 2) execution of trusted code; 3) key management in secure network filesystems.In particular, we present an experimental Linux OS distribution (SalSA), which addresses the security issues related to downloading packages and to updating an operating system through the Internet.  相似文献   
105.
In this report, we conducted a secondary analysis of the Treatment of SSRI-Resistant Depression in Adolescents (TORDIA) study to explore the impact of specific cognitive–behavioral therapy (CBT) treatment components on outcome. In TORDIA, 334 youths (ages 12 to 18 years) with major depressive disorder who had failed to respond to an adequate course of selective serotonin reuptake inhibitor (SSRI) medication were randomized to a medication switch (either to an alternative SSRI or venlafaxine) with or without 12 weeks of adjunctive CBT. Participants who had more than 9 CBT sessions were 2.5 times more likely to have adequate treatment response than those who had 9 or fewer sessions. CBT participants who received problem-solving and social skills treatment components, controlling for number of sessions and other confounding variables, were 2.3 and 2.6 times, respectively, more likely to have a positive response. These preliminary findings underscore the importance of receiving an adequate number of sessions to attain an adequate clinical response. Finally, social skills and problem solving may be active elements in CBT for adolescent depression and should be considered in treatment by those working with seriously depressed youths. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
106.
The Nuclear Hydrogen Initiative (NHI) of the U.S. Department of Energy′s Office of Nuclear Energy Science and Technology is supporting an effort to reevaluate thermochemical cycles reported in the literature as having both promising efficiencies and proof-of-concept results. Recognizing that the calculation of efficiencies was not always consistently done or well defined in the literature, we first developed a consistent methodology for reevaluating the candidate thermochemical cycles. This methodology was defined for three levels of maturity in process knowledge. Argonne National Laboratory and a group of universities recalculated the efficiency for each level and identified the most critical R&D necessary to further assess the cycles' potential. This methodology is illustrated with the Cu–Cl in Part I of this series of three papers. Current results of the analyses for all of the cycles are summarized in Part II. Part III contains a more detailed Level 3 analysis for the Cu–Cl cycle.  相似文献   
107.
108.
Multi-objective optimisation problems have seen a large impulse in the last decades. Many new techniques for solving distinct variants of multi-objective problems have been proposed. Production scheduling, as with other operations management fields, is no different. The flowshop problem is among the most widely studied scheduling settings. Recently, the Iterated Greedy methodology for solving the single-objective version of the flowshop problem has produced state-of-the-art results. This paper proposes a new algorithm based on Iterated Greedy technique for solving the multi-objective permutation flowshop problem. This algorithm is characterised by an effective initialisation of the population, management of the Pareto front, and a specially tailored local search, among other things. The proposed multi-objective Iterated Greedy method is shown to outperform other recent approaches in comprehensive computational and statistical tests that comprise a large number of instances with objectives involving makespan, tardiness and flowtime. Lastly, we use a novel graphical tool to compare the performances of stochastic Pareto fronts based on Empirical Attainment Functions.  相似文献   
109.
The aim of this paper is to present a picture of student experience of a collaborative e-learning module in an asynchronous e-learning environment. A distance learning module on music education worth five credit points for a bachelor online degree for primary school educating teachers was assessed using a self-evaluation questionnaire that gathered quantitative and qualitative data about student satisfaction of the collaborative e-learning activity. The quantitative part of the questionnaire consisted of 27 closed questions on a 10-point Likert scale and offered data about satisfaction with the module. The qualitative part of the questionnaire provided an insight into the participant perspective of the online collaborative experience. General open questions on satisfaction and dissatisfaction were analyzed with an inductive analysis which showed the evaluation criteria used by 92 students. Results of the analysis showed five themes of the participants’ perspectives, which were interpreted by the researcher as: teamwork, cognitive, operating, organizing, and emotive/ethic for the positive aspects and teamwork, operating, organizing, and emotive/ethic for the aspects to be improved. The aspects that were associated with satisfaction include: collaborating, comparing ideas, sharing knowledge and skills to support each other, peer learning, analyzing and integrating different points of view, the usability of the platform, group planning and workload management. Aspects of the student learning experience that should inform the improvements of e-learning include: more collaboration between students since some students engage differently; more coordination and organization, the workload management in the group activities, some technical problems such as updating modifications. The participants’ results in the module increased their didactic potential as primary school teachers. The findings are discussed in relation to their potential impact on developing collaborative activities addressed to teacher education in distance learning. Implications for future research are also considered.  相似文献   
110.
There are many abandoned underground mines beneath the city of Rome, created in the Pleistocene pyroclastic deposits over thousands of years. These pose a serious public safety risk hence the study was undertaken to better assess the stability of the underground workings. The Villa de Sanctis public park was selected as a suitable test site, as in this area the cavity network can be inspected and the different steps of the progressive migration of voids toward the surface can be identified. In addition to an underground geological survey, geophysical investigations were undertaken to elucidate some key characteristics of the involved lithological units, including elastic stiffness and layer thickness. Recommendations are made for further studies of the accessible and inaccessible areas.  相似文献   
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