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81.
Christelle Turchiuli Nicolas Lemarié Marie-Elisabeth CuvelierElisabeth Dumoulin 《Journal of food engineering》2013
Feasibility of producing, at pilot scale (5 kg), stable oil in water emulsions with size of 1–2 μm and 100–200 nm was investigated in relation with the oil content of the emulsion (4%, 8% and 12% w/w) and with the composition of the aqueous phase. 相似文献
82.
Marusczak N Larose C Dommergue A Paquet S Beaulne JS Maury-Brachet R Lucotte M Nedjai R Ferrari CP 《The Science of the total environment》2011,409(10):1909-1915
Total mercury (THg) and methylmercury (MeHg) concentrations were measured in the muscle of Arctic charr (Salvelinus alpinus) and in the water column of 4 lakes that are located in the French Alps. Watershed characteristics were determined (6 coverage classes) for each lake in order to evaluate the influence of watershed composition on mercury and methylmercury concentrations in fish muscle and in the water column. THg and MeHg concentrations in surface water were relatively low and similar among lakes and watershed characteristics play a major role in determining water column Hg and MeHg levels. THg muscle concentrations for fish with either a standardized length of 220 mm, a standardized age of 5 years or for individualuals did not exceed the 0.5 mg kg− 1 fish consumption advisory limit established for Hg by the World Health Organization (WHO, 1990). These relatively low THg concentrations can be explained by watershed characteristics, which lead to short Hg residence time in the water column, and also by the short trophic chain that is characteristic of mountain lakes. Growth rate did not seem to influence THg concentrations in fish muscles of these lakes and we observed no relationship between fish Hg concentrations and altitude. This study shows that in the French Alps, high altitude lakes have relatively low THg and MeHg concentrations in both the water column and in Arctic charr populations. Therefore, Hg does not appear to present a danger for local populations and the fishermen of these lakes. 相似文献
83.
Villanneau EJ Saby NP Marchant BP Jolivet CC Boulonne L Caria G Barriuso E Bispo A Briand O Arrouays D 《The Science of the total environment》2011,409(19):3719-3731
Persistent organic pollutants (POPs) impact upon human and animal health and the wider environment. It is important to determine where POPs are found and the spatial pattern of POP variation. The concentrations of 90 molecules which are members of four families of POPs and two families of herbicides were measured within a region of Northern France as part of the French National Soil Monitoring Network (RMQS: Réseau de Mesures de la Qualité des Sols). We also gather information on five covariates (elevation, soil organic carbon content, road density, land cover and population density) which might influence POP concentrations. The study region contains 105 RMQS observation sites arranged on a regular square grid with spacing of 16 km. The observations include hot-spots at sites of POP application, smaller concentrations where POPs have been dispersed and observations less than the limit of quantification (LOQ) where the soil has not been impacted by POPs. Fifty nine of the molecules were detected at less than 50 sites and hence the data were unsuitable for spatial analyses. We represent the variation of the remaining 31 molecules by various linear mixed models which can include fixed effects (i.e. linear relationships between the molecule concentrations and covariates) and spatially correlated random effects. The best model for each molecule is selected by the Akaike Information Criterion. For nine of the molecules, spatial correlation is evident and hence they can potentially be mapped. For four of these molecules, the spatial correlation cannot be wholly explained by fixed effects. It appears that these molecules have been transported away from their application sites and are now dispersed across the study region with the largest concentrations found in a heavily populated depression. More complicated statistical models and sampling designs are required to explain the distribution of the less dispersed molecules. 相似文献
84.
A personalized measure for thermal comfort has been applied for use in combination with smart controls for building automation. Using data from a field study, we first show the superiority of personalized measures for thermal comfort compared to standard non-adaptive methods. Based on this knowledge we describe a methodology, using logistic regression techniques, to convert user votes to a probability of comfort. We also describe the interface used to collect the votes. We show that, for a given subject, our thermal profile converges against the probabilities found in the field study. As a case study we implemented the measure in a control algorithm to control the shading devices. The results clarify the mode of action and also show the effectiveness of the method. 相似文献
85.
In this study, the mechanical properties of composite bituminous structures with geogrid products, used as an interlayer between different types of bituminous mixtures, at a constant temperature, were examined. A twofold experimental program based on new approaches was selected. A new configuration of the 3-Point Bending Test (3-PBT) was adopted to capture the J-integral and crack resistance property defined by crack resistance index (CRI) at the interface against bottom-up crack propagation. The bonding quality at the interface was also defined through a new index named coefficient of interface bonding (CIB), which was measured via a modified version of the slant shear device. The results derived from this research revealed that reinforcement of the interface, with varying degree of surface texture, by geogrid products significantly enhances the fracture toughness of the whole system in terms of the J-integral, which could be properly connected to the combined functions of bonding quality and crack resistance indices defined at the interface. 相似文献
86.
The state of stress and its implications for shear on fault planes during fluid injection are crucial issues for the HDR (Hot Dry Rock) or EGS (Enhanced or Engineered Geothermal System) concept. This is especially true for hydraulic stimulation experiments, aimed at enhancing the connectivity of a borehole to the natural fracture network, since they tend to induce the shearing of fractures, which is controlled by the local stress regime.During the 2000 and 2003 stimulation tests at Soultz-sous-Forêts, France, about 10,000 microearthquakes were located with a surface seismological network. Hundreds of double-couple (DC) focal mechanisms were automatically determined from first-motion polarities using the FPFIT program [Reasenberg, P.A., Oppenheimer, D., 1985. FPFIT, FPPLOT and FPPAGE: Fortran computer programs for calculating and displaying earthquake fault-plane solutions. US Geological Survey Open-File Report 85-739, 25 pp.]. The majority of these mechanisms indicate normal-faulting movement with a more or less pronounced strike-slip component. Some quasi-pure strike-slip events also occurred, especially in the deeper part of the stimulated rock volume, at more than 5 km depth.Although we found a double-couple solution for all events, we tried to observe and quantify the proportion of the non-double-couple (NDC) component in the seismic moment tensor for several microseisms from the 2003 data. The study shows that the NDC is higher for the events in the vicinity of the injection well than for the events far from the well.We used the method of Rivera and Cisternas [Rivera, L., Cisternas, A., 1990. Stress tensor and fault-plane solutions for a population of earthquakes. Bull. Seismol. Soc. Am. 80, 600–614.] to perform the inversion of the deviatoric part of the stress tensor from P-wave polarities. This method was applied to different datasets from the 2000 test, taken from the shallower and deeper parts of the stimulated region. The results show a stable, horizontal, NE-SW-oriented trend of the minor horizontal stress, but a rotation of the major stress from a sub-vertical direction (top of the stimulated region) to a sub-horizontal one (bottom of the stimulated region). This implies a change from a normal-faulting to a strike-slip regime, in agreement with our fault-plane solutions. Finally, we applied the stress components to the nodal planes of several events and were able to determine their fault plane and obtain a 3D image of the fracture network, based on real data. 相似文献
87.
Nicolas Szilas 《Applied Artificial Intelligence》2013,27(8):753-801
One goal of interactive narrative and drama is to create an experience while utilizing the computer where the user is one main character in the story. This goal raises a set of practical and theoretical challenges to artificial intelligence. In particular, an intelligent narrator has to dynamically maintain a satisfactory storyline and adapt to the user intervention. After reviewing the existing approaches to interactive drama, an original model is described, based on several theories on narrative. This model is based on a rule-based component for the generation of meaningful narrative actions and on a model of the user for the ranking of these actions and the action selection. A simple but authorable text generation system is also described, for the display of the actions on the computer. The system is implemented on a real-size scenario and experimental results are discussed. We conclude by discussing the possibility of a wider application of our approach within the field of AI. 相似文献
88.
Claudio Schepke Nicolas Maillard Joerg Schneider Hans-Ulrich Heiss 《International journal of parallel programming》2013,41(4):552-569
Forecast precisions of climatological models are limited by computing power and time available for the executions. As more and faster processors are used in the computation, the resolution of the mesh adopted to represent the Earth’s atmosphere can be increased, and consequently the numerical forecast is more accurate. However, a finer mesh resolution, able to include local phenomena in a global atmosphere integration, is still not possible due to the large number of data elements to compute in this case. To overcome this situation, different mesh refinement levels can be used at the same time for different areas of the domain. Thus, our paper evaluates how mesh refinement at run time (online) can improve performance for climatological models.The online mesh refinement (OMR) increases dynamically mesh resolution in parts of a domain,when special atmosphere conditions are registered during the execution. Experimental results show that the execution of a model improved by OMR provides better resolution for the meshes, without any significant increase of execution time. The parallel performance of the simulations is also increased through the creation of threads in order to explore different levels of parallelism. 相似文献
89.
Nicolas Vuillerme Nicolas Pinsault Olivier Chenu Anthony Fleury Yohan Payan Jacques Demongeot 《Pervasive and Mobile Computing》2009,5(3):268-275
We describe the architecture of an original biofeedback system for balance improvement for fall prevention and present results of a feasibility study. The underlying principle of this biofeedback consists of providing supplementary information related to foot sole pressure distribution through a wireless embedded tongue-placed tactile output device.Twelve young healthy adults voluntarily participated in this experiment. They were asked to stand as immobile as possible with their eyes closed in two conditions of no-biofeedback and biofeedback. Centre of foot pressure (CoP) displacements were recorded using a force platform. Results showed reduced CoP displacements in the biofeedback relative to the no-biofeedback condition.On the whole, the present findings evidence the effectiveness of this system in improving postural control on young healthy adults. Further investigations are needed to strengthen the potential clinical value of this device. 相似文献
90.
Ismail Yurtdas Nicolas Burlion Frédéric Skoczylas 《Cement and Concrete Research》2006,36(7):1286-1293
Concrete materials are submitted to drying when the relative humidity of their surrounding is decreasing. The main purpose of this study is to highlight the variation of multiaxial mechanical behaviour of mortars which depends on desiccation level and cement paste properties (quality). The behaviour under discussion includes uniaxial and triaxial strengths, elastic properties and volumetric strains due to hydrostatic loading. Multiaxial experiments, carried out on two mortars for which the only difference was the water by cement ratio (w / c = 0.5 and 0.8), show a competitive effect between the increase in material rigidity due to capillary suction and saturation gradients, and the microcracking which comes from material heterogeneity and differential shrinkages of the sample. This effect mainly depends on cement paste properties and its porosity; therefore the capillary suction effect is preponderant for a high paste quality (i.e. lower porosity) while a low paste quality would be more sensitive to microcracking. 相似文献