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991.
992.
Alegria F.A.C. da Cruz Serra A.M. 《IEEE transactions on instrumentation and measurement》2005,54(6):2305-2309
This paper presents a study about the amount of overdrive to use when analog-to-digital converters (ADCs) are tested with the ramp histogram method. Overdrive is used to limit the error induced by input-equivalent noise in the estimation of the ADC transition voltages. This study has direct application in the new coarse ramp static test. 相似文献
993.
Elton Bauer Jose G.G. de Sousa Elvio A. Guimarães Francisco Gabriel S. Silva 《Building and Environment》2007
The Vane method (Vane test) is a simple but efficient method to measure the yield stress among other properties of non-Newtonian fluids. These fluids exhibit big flow effects in flat surfaces which are common in rheometers devices of different types (parallel disk or coaxial cylinder types). The yield stress values obtained with Vane method, in pastes, gels, soils and concentrated suspensions, have presented good agreement with results found elsewhere by most of the rheologic methods shown in the literature. The aim of this work is presenting a discussion on the capabilities of the Vane method, highlighting the theoretical basis, the functioning principle with some operational particularities, and some applications of the method in investigating the properties of fresh rendering mortars. 相似文献
994.
In this paper we propose a metaheuristic to solve a new version of the Maximum Capture Problem. In the original MCP, market
capture is obtained by lower traveling distances or lower traveling time, in this new version not only the traveling time
but also the waiting time will affect the market share. This problem is hard to solve using standard optimization techniques.
Metaheuristics are shown to offer accurate results within acceptable computing times. 相似文献
995.
da Cunha M.P. Adler E.L. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1995,42(2):168-173
In developing models to characterize the metallic-finger step discontinuity in SAW devices on piezoelectric substrates it is important to estimate the SAW reflection coefficients and the effect of other modes at step discontinuities. In the literature perturbation approximations, finite element methods and various phenomenological parameter-fitting using experimental data are among the techniques which have been exploited. In this paper, a nonperturbation approximation method, which attempts to parallel some well-established techniques used in solving electromagnetic waveguide-discontinuity problems, is explored as an alternate numerical procedure for calculating SAW reflections. Implementing such a method requires that the full solution to SAW propagation in the free and in the layered regions be obtained. Thus, for a free-to-metallized discontinuity, the two SAW phase velocities, the total SAW power now in the free region and in the layered region, and the electroacoustic fields, must be calculated. In this paper the reflection problem is formulated as an optimization problem subject to the necessary scattering parameter constraints. Numerical experiments are described, and the results of calculations for reflectivity are compared to perturbation approximations, nonperturbation approximations and the available experimental data for the effects of energy storage 相似文献
996.
997.
JM Lapierre V Cacheux F Da Silva N Collot N Hervy J Wiss G Tachdjian 《Canadian Metallurgical Quarterly》1998,41(1):56-62
PURPOSE: To define, in a phase I study in relapsed non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia (CLL), the maximum-tolerated dose (MTD), major toxicities, and possible antitumor activity of bryostatin 1, a macrocyclic lactone. PATIENTS AND METHODS: Bryostatin 1 was delivered by 72-hour continuous infusion every 2 weeks to patients with relapsed NHL or CLL, at doses that ranged from 12 microg/m2 to 180 microg/m2 per course. Correlative investigations included evaluations of total protein kinase C (PKC) in peripheral blood and lymphoid differentiation in patient tumor tissue. RESULTS: Twenty-nine patients were treated, including three patients with CLL and 26 with NHL. Generalized myalgia was the dose-limiting toxicity (DLT) and occurred in two of three patients treated with bryostatin 1 at 180 microg/m2 per course. Myalgias were dose-related and cumulative, and often started in the thighs and calves, improved with activity, were somewhat responsive to analgesics, and often took weeks to resolve once taken off study. Six patients were treated at the MTD of 120 microg/m2 per course. Myalgia, headache, and fatigue were common. Hematologic toxicity was uncommon. Total cumulative doses of bryostatin 1 up to 1,134 microg/m2 have been administered without untoward toxicity. Eleven patients achieved stable disease for 2 to 19 months. An in vitro assay for total PKC evaluation in patient peripheral-blood samples demonstrated activation within the first 2 hours with subsequent downregulation by 24 hours, which was maintained throughout the duration of the 72-hour infusion. CONCLUSION: This phase I study defined the MTD and recommended phase II dose of bryostatin 1, when administered over 72 hours every 2 weeks, to be 120 microg/m2 (40 microg/m2/d for 3 days). Generalized myalgia was the DLT. Future studies will define the precise activity of bryostatin 1 in subsets of patients with lymphoproliferative malignancies and its efficacy in combination with other agents. 相似文献
998.
Management of complexity, changes and disturbances is one of the key issues of production today. Distributed, agent-based structures represent viable alternatives to hierarchical systems provided with reactive/proactive capabilities. In the paper, approaches to distributed manufacturing architectures are surveyed, and their fundamental features are highlighted, together with the main questions to be answered while designing new structures. Moreover, an object-oriented simulation framework for development and evaluation of multi-agent manufacturing architectures is introduced. 相似文献
999.
M De Silva 《Canadian Metallurgical Quarterly》1998,69(5):970-971
OBJECTIVE: To review published data and to compare pregnancy rates (PRs) after culturing human embryos with and without glucose and phosphate. DESIGN: Comparison of results from various programs. SETTING: Assisted Reproductive Technology Program. PATIENT(S): Patients were enrolled in various studies. INTERVENTION(S): Human embryos were cultured with and without glucose and phosphate. MAIN OUTCOME MEASURE(S): Pregnancy rates after different techniques of embryo culture. RESULT(S): Some studies reported higher PRs in patients undergoing IVF after embryos were cultured in media without glucose and phosphate versus media with glucose and phosphate. One study showed that PRs were lower when embryos were cultured in media lacking glucose and phosphate compared with media containing glucose and phosphate. Some studies have also shown similar PRs with the two types of culture media. CONCLUSION(S): The PRs in IVF patients will not necessarily be enhanced if the embryos are cultured in media without glucose and phosphate. 相似文献
1000.
Can computer science learn from the social sciences? We focus our discussions on an undesired phenomenon that commonly affects software developers. Known as the Pygmalion effect, this phenomenon has been studied intensely by social scientists but almost entirely ignored by computer scientists. Pygmalion was a sculptor who fell in love with his statue, Galatea, brought to life for him by Aphrodite. In the 1960s, R. Rosenthal and L. Jacobson, two American psychologists, used this myth to name an observation of theirs: whenever someone evaluates something, the evaluator's expectations concerning the evaluated object influence the evaluation, in a way that tends to prove the evaluator's initial hypothesis. Intensive studies since then have confirmed this initial observation: virtually every evaluation process in which humans intervene is prone to the Pygmalion effect, and computer science is no exception: the expectations of computer systems evaluators can strongly bias the outcome of the evaluation 相似文献