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71.
Cox W. Miles; Fadardi Javad Salehi; Pothos Emmanuel M. 《Canadian Metallurgical Quarterly》2006,132(3):443
Decisions about using addictive substances are influenced by distractions by addiction-related stimuli, of which the user might be unaware. The addiction-Stroop task is a paradigm used to assess this distraction. The empirical evidence for the addiction-Stroop effect is critically reviewed, and meta-analyses of alcohol-related and smoking-related studies are presented. Studies finding the strongest effects were those in which participants had strong current concerns about an addictive substance or such concerns were highlighted through experimental manipulations, especially those depriving participants of the substance. Theories to account for addiction-related attentional bias are discussed, of which the motivational theory of current concerns appears to provide the most complete account of the phenomenon. Recommendations are made for maximizing the precision of the addiction-Stroop test in future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Fereidoon Moghadas Nejad Javad Tanzadeh Gholam Hossein Hamedi 《International Journal of Pavement Engineering》2016,17(4):353-362
Rutting is considered as one of the major damages in asphalt mixtures. In this study, different types of nanoparticles such as TiO2, Al2O3, Fe2O3 and ZnO in different percentages were added to the base asphalt binder in order to decrease the rutting potential of hot-mix asphalt (HMA). In the first step, asphalt binder tests for characteristics such as penetration grade, ductility, softening point and viscosity were performed on the asphalt binder modified by the nanoparticles. Then, after preparing HMA samples, the static creep test was done at two stress levels at a specific temperature. Results of this study showed that using the nanoparticles improved the behavioural properties of the asphalt binder and decreased rutting in asphalt mix samples. Furthermore, scanning electron microscope images taken from the asphalt binder samples modified by the nanoparticles demonstrated that these nanoparticles were properly distributed in the asphalt binder space and had a positive effect on the rutting performance of the asphalt mixes. 相似文献
73.
Javad Akbari Torkestani 《控制论与系统》2013,44(1):77-93
Job scheduling is one of the key issues in the design of grid environments. The performance of the grid system severely degrades if a method does not exist to efficiently schedule the user jobs. In this article, a fully distributed, learning automata–based job scheduling algorithm is proposed for grid environments. The proposed method is composed of two types of procedures: in the first, a procedure is run at the grid nodes and in the second, the procedure is run at the schedulers. The proposed algorithm synchronizes the performance of the schedulers by the learning automata that select their actions using the pseudo-random number generators with the same seed. In this method, the grid computational capacity that is allocated to each scheduler is proportional to its workload. To show the efficiency of the proposed method, several simulation experiments were conducted under different grid scenarios. The obtained results show that the proposed algorithm outperforms several well-known methods in terms of makespan, flow time, and load balancing. 相似文献
74.
Yasser Maghsoudi Mohammad Javad Valadan Zoej Michael Collins 《International journal of remote sensing》2013,34(15):4311-4326
The rapid advances in hyperspectral sensing technology have made it possible to collect remote-sensing data in hundreds of bands. However, the data-analysis methods that have been successfully applied to multispectral data are often limited in achieving satisfactory results for hyperspectral data. The major problem is the high dimensionality, which deteriorates the classification due to the Hughes Phenomenon. In order to avoid this problem, a large number of algorithms have been proposed, so far, for feature reduction. Based on the concept of multiple classifiers, we propose a new schema for the feature selection procedure. In this framework, instead of using feature selection for whole classes, we adopt feature selection for each class separately. Thus different subsets of features are selected at the first step. Once the feature subsets are selected, a Bayesian classifier is trained on each of these feature subsets. Finally, a combination mechanism is used to combine the outputs of these classifiers. Experiments are carried out on an Airborne Visible/Infrared Imaging Spectroradiometer (AVIRIS) data set. Encouraging results have been obtained in terms of classification accuracy, suggesting the effectiveness of the proposed algorithms. 相似文献
75.
Javad Ahmadi Ali Khaki-Sedigh Abdolreza Ohadi 《International journal of control》2013,86(9):1380-1400
In this article, a new methodology for robust actuator weighting in the control allocation (CA) problem of input redundant feedback systems is addressed. The methodology is based on the control structural properties of the plant which were previously used for control configuration selection. Robust performance (RP) measures including H ∞ norm and structured singular value of the closed-loop system are used in this article. The capability of the approach is proven with application to lateral dynamics control of the vehicle over-actuated with front and rear steering systems. Employing the RP measures, it is concluded that the vehicle feedback control with front steering angles gives superior RP properties in comparison with the feedback loop of the rear steering angles. Based on these results, the penalty weightings in the cost function of the CA unit are determined. Simulation results based on nonlinear seven degrees of freedom vehicle handling model show that the selection of penalty weightings in the CA unit based on the RP properties of the control inputs (front and rear steering angles) improves the RP of the closed-loop. 相似文献
76.
77.
Sodeif Azadmard-Damirchi Mahboob Nemati Javad Hesari Masoud Ansarin Bahram Fathi-Achachlouei 《Journal of the American Oil Chemists' Society》2010,87(10):1155-1159
Phytosterols are separated into three classes: 4-desmethylsterols, 4-monomethylsterols and 4,4′-dimethylsterols. 4,4′-Dimethylsterols
are used to detect vegetable oil adulteration and some compounds from this class can have anti-inflammatory and anticancer
properties. There are methods such as thin layer chromatography (TLC) and solid phase extraction (SPE) used to separate phytosterol
classes from each other. However, in some cases, separation of all three classes is not required. In addition, TLC has some
drawbacks such as low recovery and it is time consuming. An SPE method has previously been used, but it was necessary to use
high volume of solvents with this method to avoid coelution of phytosterol classes. In this study, an SPE (silica, 1 g) method
was developed to separate and enrich only 4,4′-dimethylsterols from unsaponifiables of vegetable oil samples using 25 mL n-hexane and diethyl ether (95:5, v:v). This method was applied to hazelnut and olive oils and results were compared with those
of TLC and the previously developed SPE method. Recovery of 4,4′-dimethylsterols was two times higher with the new SPE method
compared with the TLC method. The newly developed SPE method generally gave a similar recovery compared with the previously
developed SPE method. Moreover, the SPE method developed in this study has the advantage of using a 3.5 times lower volume
of solvent than previously developed SPE methods. Because the newly developed SPE method has a single step requiring a low
volume of solvents, it is rapid and simple, and can easily be used to detect olive oil adulteration with hazelnut oil and
to analyze and quantify effective nutritional compounds in the 4,4′-dimethylsterols class. 相似文献
78.
79.
Mehrorang Ghaedi Javad Tashkhourian Arezoo Amiri Pebdani Batol Sadeghian Fatemeh Nami Ana 《Korean Journal of Chemical Engineering》2011,28(12):2255-2261
The proposed research describes the synthesis and characterization of platinum nanoparticles loaded on activated carbon (Pt-NP-AC)
and its efficient application as novel adsorbent for efficient removal of reactive orange 12 (RO-12). The influences of effective
parameters following the optimization of variables on removal percentages, their value was set as 0.015 g Pt-NP-AC, pH 1,
contact time of 13 min. At optimum values of all variables at 25 and 50 mgL−1 of RO-12 enthalpy (ΔH0) and entropy (ΔS0) changes was found to be 59.89 and 225.076, respectively, which negative value of ΔG0 shows a spontaneous nature, and the positive values of ΔH0 and ΔS0 indicate the endothermic nature and adsorption organized of dye molecule on the adsorbent surface. Experimental data was
fitted to different kinetic models including first-order, pseudo-second-order, Elovich and intra-particle diffusion models,
and it was seen that the adsorption process follows pseudo-second-order model in consideration to intra-particle diffusion
mechanism. At optimum values of all variables, the adsorption process follows the second-order kinetic and Langmuir isotherm
model with adsorption capacity 285.143 mg g−1 at room temperature. 相似文献
80.
In this study, carbon monoxide removal by preferential oxidation in a hydrogen-rich stream is simulated between two parallel infinite plates of 150 μm distance. A three-step kinetic is considered that includes carbon monoxide oxidation, hydrogen oxidation and water–gas shift reaction. The walls temperature is in the range of 80–120 °C. The function of this microreactor is to reduce carbon monoxide content from about 2% to below 10 ppm, suitable for use in a PEM fuel cell. Based on the problem conditions, the flow is in the continuum regime and application of the Navier–Stokes equations is admissible. In order to simulate the reacting flow, continuity, conservations of x- & y-momentum, conservation of energy, conservation of species, state equation and reaction rates are simultaneously solved through SIMPLE algorithm by utilizing power-law scheme. Effects of important parameters including walls temperature, steam content, CO content and O2/CO are assessed. It is observed that increasing walls temperature or oxygen content will increase both CO selectivity and conversion. It is also found that by steam addition, CO conversion is improved without significant change of CO selectivity. These results are in good agreement with previous published data. 相似文献