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21.
The electrochemical oxidation of aqueous wastes polluted with hydroquinone, resorcinol, or catechol on boron-doped diamond electrodes has been studied. The complete mineralization of the organic waste has been obtained independently of the nature of each isomer. No aromatic intermediates were found during the treatment, and solely aliphatic intermediates (carboxylic acids C4 and C2, mainly) were detected in the three cases. Although as from the bulk electrolyses study no differences in the electrochemical oxidation of dihydroxybenzenes seem to exist, different voltammetric behavior between resorcinol and the other two isomers was obtained in the voltammetric study. Catechol and hydroquinone have a reversible quinonic form, and a cathodic reduction peak appears in their voltammograms. The characterization of the first steps in the electrochemical oxidation of the three dihydroxybenzenes showed the formation of a larger number of intermediates in the oxidation of catechol, although no carbon dioxide was detected in its oxidation. Conversely, the oxidation of resorcinol and hydroquinone lead to the formation of important concentrations of carbon dioxide. The nondetection of aromatic intermediates, even if small quantities of charge are passed, confirms that the oxidation must be carried out directly on the electrode surface or by hydroxyl radicals generated by decomposition of water.  相似文献   
22.
Currently commercialised stand-alone street lighting systems based on the classical configuration coupling photovoltaic cells (PV) and battery cannot work all the year round in regions that are far from the equator. To improve the classical system, a hybrid system coupling a PV, a battery and a fuel cell is proposed. However, the sizing method of hybrid systems is a key issue in obtaining the cheapest system. To optimise the system, an original time-saving method is applied. Two optimization methods are used: first the genetic algorithms, then the simplex algorithms. A simulation model is used to evaluate the validity of the different hybrid configurations. After presenting the problem of stand-alone street lighting, the optimization methodology and the simulation model are detailed. Finally, an optimal configuration is obtained and shows that a 60 W street light would cost 7150€ with a lifetime of 25 years. The optimised parameters are also given and analysed.  相似文献   
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Adsorption of vegetable oil components, either as pure molecules or as mixtures, on alumina membranes was investigated by diffuse reflectance Fourier transform infrared spectroscopy. All tested compounds displayed very similar spectra. Triolein and diolein physically adsorb onto alumina by hydrogen bonding with the carbonyl groups of the carboxylic ester and surface hydroxyls. Monolein most likely interacts with glycerol hydroxyls, while phospholipids appear to adsorb either by the ester carbonyl or charged phosphate group. Due to the catalytic properties of alumina some hydrolysis takes place during treatments. The resulting oleic acid, most likely chemisorbs by ionic interactions with the carboxylic C=O bond of the alumina. The fact that no change in the symmetric and asymmetric CH2 stretches is noticed in comparison with the free (unbound) form indicates that the molecules are not parallel, but at an angle to the surface. When alumina comes into contact with increasing amounts of crude vegetable oils a broadening of the band at 3280 cm‐1 indicates an increasing adsorption of molecules with free hydroxyls, such as mono‐ and di‐acylglycerols or phospholipids. Among all oil components, sodium oleate seems to adsorb preferentially to alumina. However, a subsequent adsorption of a lipidic monolayer at the membrane surface or even inside the pores, is not consistent with the drastic flux reduction observed in previous studies during microfiltration, and could only initiate formation or/and deposition of macromolecular structures inside membrane pores.  相似文献   
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The International Olive Council(IOC) is an international intergovernmental organization dedicated to olive oil and table olives, aiming at modernizing olive production, coordinating olive policies, improving the regulation of international trade, defending the quality of the olive sector and promoting olive oil and table olives to increase their consumption. The IOC grants recognition of laboratories and tasting panels in annual trials when they meet the conditions given in the decisions adopting the IOC certificate for laboratories for the physico–chemical testing of olive oil and laboratories for the sensory analysis of virgin olive oils. The IOC establishes analysis methods applying to olive oils and olive pomace oils for purity, quality and organoleptic assessment. The IOC elaborates guides of storage conditions for olive oils and olive pomace oils, of managing virgin olive oil tasting panels and of sensory testing laboratories. In future works, the IOC includes activities to identify analytical criteria for detecting fraud and guaranteeing the quality of olive oils and olive pomace oils.  相似文献   
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The Journal of Supercomputing - Molecular docking techniques are widely used in computational drug discovery. Most of these techniques simulate the way that a ligand interacts with a protein target...  相似文献   
28.
Recently, academic and industrial research communities are paying more explicit attention to the 5G multiple radio access technology ultra‐dense networks (5G multi‐RAT UDNs) for boosting network capacity, especially in UD urban zones. To this aim, in this paper, we intend to tackle the user association problem in 5G multi‐RAT UDNs. By considering the decoupled uplink/downlink access (DUDA), we divide our user association problem into two distinct subproblems representing, respectively, the uplink and the downlink channels. Next, we formulated each one as a nonlinear optimization problem with binary variables. Then, to solve them, we were restricted by the hard complexity, as well as the hard feasibility of centralized user association schemes. Thus, to resolve our user association problem in a reasonable time and distributed manner, we formulated each subproblem as a many‐to‐one matching game based on matching theory. Next, we provide two fully distributed association algorithms to compute the uplink and downlink stable matching among user equipments (UEs) and base stations (BSs). Simulation results corroborate our theoretical model and show the effectiveness and improvement of our achieved results in terms of the overall network performance, quality of service (QoS), and energy efficiency (EE) of UEs.  相似文献   
29.
Abstract

This paper deals with the problem of estimating the Minimum Initial Marking (MIM) of Labeled Petri Nets (L-PN). By the observation of a sequence of labels, we determine the set of possible MIMs related to a given L-PN through an approach based on GRASP (Greedy Randomized Adaptive Search Procedure) inspired method – GMIM. The objective is to get the maximum of feasible MIMs by exploring the search space and giving best solutions for real time cyber systems in short time. We consider four basic assumptions during the reasoning: (i) the L-PN structure is known; (ii) for each transition of L-PN, a label is associated, (iii) the label sequence is known, and (iv) all transitions of L-PN are observable. We show the validity and efficiency of our approach by applying the proposed GMIM metaheuristic to two validation examples: Initialization of two parallel machines (example widely cited in literature) and resources allocation in a monitoring problem via mobile robot network.  相似文献   
30.
This paper proposes a genetic algorithms (GA) optimization technique applied to power system stabilizer (PSS) for adapt a robust H2 control based on linear quadratic controller (LQ) and Kalman Filter applied on automatic excitation control of powerful synchronous generators, to improve stability and robustness of power system type single machine connected to an infinite bus system (SMIB). Adaptation technique proposed of the robust H2 control with the various electrical and mechanical parametric variations based on the optimization of the PSS parameters. The genetic algorithms is a search technique based on the mechanisms of natural selection of a genetic and evolution. This optimization technique is more used in the field of control for solve optimal choice problem of regulators parameters. The integration of GA to robust H2 control with robustness test (electrical and mechanical parameters variations of the synchronous machine) show considerable improvements in dynamics performances, robustness stability and good adaptation of the robust H2-PSS parameters under uncertain constraints. This present study was performed using our realized Graphical User Interface (GUI) developed under MATLAB.  相似文献   
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