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81.
Fatty liver samples from duck were treated with high pressures and packaged in multilayer films. Microbiological analysis, permeability of the films to oxygen and fat loss, caused by melting, were assessed after pressure or thermal treatment. Microbiological analysis showed a noteworthy reduction in the total aerobic mesophilic flora and eradication of the coliform flora, whichever film or treatment was used. Nevertheless, a significant bacterial flora was observed during storage at 4 °C from 42 days with a polyethylene/polyamide/polyethylene film and a sample which had been treated with pressure. But, treatment at 550 MPa for 55 °C and 20 min, in combination with two low oxygen permeability films (ethylene and vinyl alcohol copolymer) gave a product with long storage life (90 days) at 4 °C and a significant reduction in the melting of lipids.  相似文献   
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83.
Mediterranean Hydrogen Solar (MedHySol) is a federator project for development of a massive hydrogen production starting from solar energy and its exportation within a framework of a Euro–Maghrebian Cooperation project for industrial and energetic needs in the Mediterranean basin. The proposal of this project is included in the Algiers Declaration's on Hydrogen from Renewable Origin following the organization of the first international workshop on hydrogen which was held in 2005. Algeria is the privileged site to receive the MedHySol platform. The objective of the first step of the project is to realize a technological platform allowing the evaluation of emergent technologies of hydrogen production from solar energy with a significant size (10–100 kW) and to maintain the development of energetic rupture technologies. The second step of the project is to implement the most effective and less expensive technologies to pilot great projects (1–1000 MW). In this article we present the potentialities and the feasibility of MedHySol, as well as the fundamental elements for a scientific and technical supervision of this great project.  相似文献   
84.
Nanostructured palladium particles (nanorods, icosahedra, cubes) were synthesized in aqueous solution using a seeding-mediated approach with a structure-directing agent. These nanostructured Pd particles were then impregnated onto hydrogenotitanate nanotubes using two different impregnation procedures. The as-prepared catalysts were then tested in the selective hydrogenation of cinnamaldehyde at 323 K under 10 bars of H2. The selectivity is influenced by the morphology of the Pd nanostructured particles with a higher selectivity into saturated alcohols when the proportion of (111) Pd sites increases.  相似文献   
85.
    
The aim of this paper is to control an electromagnetic wave that penetrates in a medium with some missing information about its physical properties. The missing value of wave velocity of propagation leads us to use averaged control notion which is recently introduced by E. Zuazua, also the boundary Dirichlet condition is unknown which requires using the notion of no-regret control introduced by J. L. Lions. In this work, we combine these two techniques where we introduce the notion of averaged no-regret control to solve our optimal control problem with missing data. The averaged no-regret control will be characterised by an optimality system.  相似文献   
86.
Three different varieties of mesoporous silicas were synthesized by varying the postsynthesis treatment of an as-synthesized ordered mesoporous material type MCM-41. The resulting materials consisted of a purely siliceous MCM-41, a pore-expanded MCM-41 (PE-MCM-41C), and a surfactant-laden pore-expanded MCM-41 (PE-MCM-41E) and were evaluated as adsorbents for two types of volatile organic compounds, i.e., chlorinated and aromatic hydrocarbons. Values of heat of adsorption and Henry's law constant were determined by pulse chromatography. Additionally, adsorption capacities were calculated with a dynamic method using breakthrough curves for single components in dry and humid environments. The surfactant-containing material exhibited good compatibility with chlorinated compounds in terms of heat of adsorption and efficiency in gaseous streams containing moisture. Purely siliceous mesoporous materials, i.e., MCM-41 and PE-MCM-41C, were more selective toward aromatic hydrocarbons but also gave rise to exceptionally strong adsorption.  相似文献   
87.
This paper studies the performance of a solar tower power plant (STPP) with chimney effect based on renewable energy proposed for electricity production. That's way, a solar tower prototype was constructed and tested in the Research and Technology Centre of Energy (CRTEn), Borj Cédria, northern Tunisia.The design involves heating air using solar energy and the chimney effect to raise the hot air up the chimney stack. The hot air velocity increases by the use of a convergent nozzle to reach a suitable velocity which can run the wind turbine. The kinetic energy of the hot air is then converted to electricity by the wind turbine.During this study, the influence of the climatic conditions of Borj Cédria site (insulation, ambient temperature) as well as the chimney height and the collector diameter on the amount of electricity production were investigated.The distribution and the evolution of the temperature at different positions of the prototype as well as the electrical energy produced were determined.The results reveal that when the temperatures reach 45 °C, the electric power reaches an average value of about 0.3 W/m2 for a solar tower prototype with 8 m of diameter and 2 m of height chimney.  相似文献   
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89.
    
The climate in Algeria can be considered semiarid in most areas. The water demand is expected to increase because of population growth in the coming years. Water supply is always a great concern for the populations in the landlocked regions. Pumping water using the solar photovoltaic energy is a well‐suited solution where the traditional electricity grid is absent. Indeed, the majority of these regions are very sunny, and water is available in underground aquifers. Our system consists on a photovoltaic generator (PVG), a direct current (DC)‐DC converters, a multilevel inverter with five levels, and an asynchronous motor coupled to a centrifugal pump. The objective of this process is to ensure the operation at maximum power of the PVG system under various conditions by the maximum power point tracking (MPPT) method based on fuzzy logic control (FLC). The modeling and simulation of this system were carried out and based on our experimental work in the site meteorological database of city Adrar in Algeria. This system avoids the use of a motor pump (diesel) and eliminates costs and operating constraints in an environment friendly manner according to the COP21 recommendation.  相似文献   
90.
    
This paper deals with the attitude stabilization problem of a rigid body, where neither the angular velocity nor the attitude is used in the feedback; only body‐referenced vector measurements are needed. The proposed control scheme is based on an angular velocity observer‐like system relying solely on vector measurements. The proposed controller ensures almost global asymptotic stability and provides some interesting performance properties through an appropriate tuning of the control gains. The performance and effectiveness of the proposed control scheme are illustrated via simulation results where the control gains are adjusted using a nonlinear optimization. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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