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321.
322.
A porous polylactic acid (PLA) film was investigated as a separator for supercapacitors (SCs) and compared with commercial separators, for example, NKK-MPF30AC and Celgard 2400. The porous PLA film was fabricated via a facile phase inversion method, and the cross-sectional scanning electron microscope images of the PLA separator film exhibited highly porous interconnected morphology for ion diffusion. The surface modification of separators was performed by radio frequency (RF) air plasma to improve wettability. The plasma modification enhanced the water uptake and swelling properties of the separators and decreased the water contact angles of PLA and Celgard 2400 films. The mechanical and dielectric properties of separators were also studied. The ionic conductivities of RF-PLA in 1 M H2SO4 and 1 M Na2SO4 were found to be 1.1 × 10−1 S/cm and 0.6 × 10−2 S/cm at room temperature, respectively. The electrochemical impedance spectroscopy of the RF-PLA SCs showed the lowest solution resistance and internal resistance.  相似文献   
323.
A homogeneous mixture of two polymers dissolved in a common solvent or a mixture of solvents was applied as a thin film. The first component was a bisphenol-A based epoxide derivative modified with tetraethoxysilane (TEOS) oligomer and the second component was a high-solids fluorinated acrylic copolymer. The thin films were coated on steel substrates and were thermally crosslinked using a methylated melamine formaldehyde and/or a polyamide-amine curing agent. The films were evaluated via x-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) with integrated energy dispersive spectroscopy (EDS). It was found that the molecular weight of the resins, fluorine content, epoxide inorganic modification, and curing agent affected the degree of stratification.  相似文献   
324.
Direct borohydride/peroxide fuel cells (DBPFCs) show progressively deteriorating performance during operation for various reasons such as decreasing reactant concentrations, gas evolution and uneven distribution of liquids. The present study aims to emphasize the importance of certain design parameters, such as bipolar plate materials, flow fields and manifold design, in determining the DBPFC performance. Bipolar materials and flow channel design have been investigated. A power density of 67 mW cm?2 has been obtained with composite graphite and parallel flow channel bipolar plates. It has increased to 87 mW cm?2 using sintered graphite and then to 93.3 mW cm?2 using sintered graphite with serpentine flow fields. The stacking of DBPFCs results in a loss of performance and unstable output. The performance has remained nearly unchanged as the cell number was increased by applying an independent cell liquid distribution network (ICLDN). Using an ICLDN, power densities of 98.3, 83.3 and 82 mW cm?2 have been obtained for single-cell, 3-cell and 6-cell stacks, respectively. Finally, a controlled oxidant feeding system (COFS) has been developed to provide stable output power, and it has demonstrated a stable output power of 6 W for 2.5 h.  相似文献   
325.
A nickel mine site located in western Turkey requires approximately 135?L/s of water for 15?years. To assess the potential impacts associated with meeting this water supply requirement, we determined alternative water resources, assessed the potential impacts associated with each resource, and selected the most feasible alternative, given the environmental and technical impacts. Three options were considered: surface water, groundwater, and treated wastewater. A low-flow analysis of Gediz River was conducted for the evaluation of using surface water. For the groundwater alternative, a three-dimensional numerical groundwater flow model of the Turgutlu-Salihli aquifer was established using MODFLOW so that the impacts of withdrawal on groundwater resources could be evaluated. The wastewater option was assessed based on the amount of wastewater generated nearby (in Turgutlu). It was determined that each option is capable of supplying the required water to the mine site. However, storage of the river water in a small dam in wet seasons for use in dry seasons and using treated wastewater would have less impact on existing water users and related ecosystems.  相似文献   
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We present herein silver nanoparticles about 4 nm in diameter coated with a binary mixture of 1-octanethiol and 2-(2-{2-[(6-mercaptohexyl)oxy]ethoxy}ethoxy)ethanol. These particles show an affinity towards optically active Eu3+ ions. The effect of the nanoparticle on the characteristic emission peaks of Eu3+ is investigated. We use the variation in emission spectra of the ion to establish its binding to the nanoparticles.  相似文献   
328.
In this study, the influence of milled crust and flour from oleaster (Elaeagnus angustifolia L.) separately added at different levels (1%, 2% and 3%) on the physical, chemical, sensory, colour properties and antioxidant properties of ice creams were investigated. The increment of crust and flour level caused an increase of dry matter, acidity, viscosity, first dripping, complete melting and vitamin C content. Flour increased overrun values in ice cream. Our results indicated that lyophilised oleaster extracts contain remarkable phenolic compounds. It was observed that lyophilised oleaster extracts exhibited a moderate in vitro antioxidant capacity. The addition of oleaster flour and crust positively affected sensory properties. The sensory results showed that ice cream containing 2% oleaster flour was the highest scored by the panellists. Oleaster flour and crust increased the sweetness of ice cream samples. These results showed that considerable nutritive and functional improvement could be attained by the addition of oleaster flour to ice cream formulation so that it could be used as natural antioxidants in ice cream as a source of flavour with complacency.  相似文献   
329.
Face recognition algorithms customarily utilize query faces captured from uncontrolled, in the wild, environments. The quality of these facial images is affected by various internal factors, including the quality of sensors used in outdoor cameras as well as external ones, such as the quality and direction of light. These factors adversely affect the overall quality of the captured images often causing blurring and/or low resolution, a phenomena commonly referred to as image degradation. Super-resolution algorithms are highly effective in improving the resolution of degraded images, more so if the captured face is small requiring scaling up. With this motivation, this research aims at demonstrating the effect of one of the state-of-the-art image super-resolution algorithms on the labeled faces in the wild (lfw) dataset. In this regard, several cases are analyzed to demonstrate the effectiveness of the super-resolution algorithm. Each case is then investigated independently comparing the order of execution before or after the 3D face alignment step. Following this, resulting images are tested on a closed set face recognition protocol using unsupervised algorithms with high-dimensional extracted features. The inclusion of super-resolution resulted in improvement in the recognition rate compared to unsupervised algorithm results reported in the literature.  相似文献   
330.
In temporal domains, agents need to actively gather information to make more informed decisions about both the present and the future. When such a domain is modeled as a temporal graphical model, what the agent observes can be incorporated into the model by setting the respective random variables as evidence. Motivated by a tissue engineering application where the experimenter needs to decide how early a laboratory experiment can be stopped so that its possible future outcomes can be predicted within an acceptable uncertainty, we first present a dynamic Bayesian network (DBN) model of vascularization in engineered tissues and compare it with both real-world experimental data and agent-based simulations. We then formulate the question of “how early an experiment can be stopped to guarantee an acceptable uncertainty about the final expected outcome” as an active inference problem for DBNs and empirically and analytically evaluate several search algorithms that aim to find the ideal time to stop a tissue engineering laboratory experiment.  相似文献   
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