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Controlling of added iron to fortified flours is very important, and the common method is spot test inaccurate method. In this study, we invented a new method based on a computer vision system. We also compared the accuracy of this method and the spot test with atomic absorption spectroscopy. In new method, ferrous sulfate particles in the samples were oxidized, and some red spots were formed on the surface of samples. The captured images from samples were changed to binary images and analyzed using the Clemex Vision 3.5 software. After processing of image, the number of colored spots and the area of spots were determined. The calibration curves were drawn, and in order to compare the sensitivity of the new method with spot test, 33 samples were selected randomly, and the amounts of added iron were detected using new method, spot test, and atomic absorption. We used t test and linear regression tests with a confidence interval of 95 % to compare the results. Results showed that there was a higher correlation (R 2?=?0.988, p?<?0.001) between new method and atomic absorption method in comparison with spot test (R 2?=?0.501, p?<?0.001). Therefore, spot test and atomic absorption can be replaced by an accurate but inexpensive method.  相似文献   
13.
Different contents of multiwalled carbon nanotube (MWCNTs) functionalized by He-dielectric barrier discharge (DBD) plasma followed by an exposure to NH3 were incorporated into PA6 matrix via a phase inversion based solution method. Optical and electron microscopic results were indicative of the excellent dispersion state of the MWCNTs. The differential scanning calorimetry and thermogravimetric analysis measurements revealed that even addition of a slight amount of the MWCNTs significantly increased the thermal stability and crystallization temperature. Moreover, the low electrical percolation threshold of the PA 6/functionalized MWCNTs nanocomposites was another confirmation for achieving a good dispersion state of MWCNTs using this approach.  相似文献   
14.
Visible light sensitive photocatalysts of Fe2O3/ZnO nanocomposites were prepared by a simple solid-state reaction method, using zinc acetate, α-Fe2O3 and sodium hydroxide at room temperature. The products were characterized by scanning electron microscopy, powder X-ray diffraction, N2 adsorption–desorption measurement, UV–vis absorption, and photoluminescence spectroscopy and used for photodecolorization of Congo red. The characterization results showed that the morphology, crystallite size, BET surface area and optical absorption of the samples varied significantly with the Fe3+ to Zn2+ ratios. The nanocomposites show two absorption edges at ultraviolet and visible region. The optical band gap values of these nanocomposites were calculated to be about 3.98–3.81 eV and 2.88–2.98 eV, which show a red shift from that of pure ZnO. These red shifts are related to the formation of Fe s-levels below the conductive band edge of ZnO and effectively extend the absorption edge into the visible region. The growth mechanisms of the samples are proposed. These nanocomposites showed high decolorization ability in visible light with wavelength up to about 400 nm. Among the samples, Fe2O3/ZnO nanoflower (molar ratio of Fe3+ to Zn2+ is 1:100) exhibited higher decolorization efficiency than the other nanocomposites. It could be considered as a promising photocatalyst for dyes treatment.  相似文献   
15.
Nanocrystalline molybdenum with a mean crystallite size of 50 nm was synthesized by mechanical activation of MoO3 powder and its subsequent hydrogen reduction. MoO3 powder was severely activated in a high energy planetary ball mill under a pure argon atmosphere. Temperature-programmed reduction (TPR) by hydrogen was used to investigate hydrogen reduction behavior of the powder samples activated for 5 and 20 h. It was found that by increasing the activation time, the peak temperature for the reduction was shifted slightly to lower temperatures and the peak for the reduction of MoO3 to MoO2 was completely separated from the one for the reduction of MoO2 to molybdenum. In order to evaluate the effect of mechanical activation on the reduction behavior of MoO3, the initial micron-sized powder and the sample activated for 20 h were reduced at similar conditions. It was found that the activated sample with finer particles was reduced faster than the un-milled sample. Hydrogen reduction of the non-activated MoO3 produced a very fine grained molybdenum powder but the crystallite size changes of the sample activated for 20 h was negligible during reduction.  相似文献   
16.
In this study, three non‐linear indices consist of compression, one‐dimensional (1D) and two‐dimensional (2D) fractal dimensions are used for the determination of the malignancy or benignity of cancer tumours in breast thermograms. On the other hand, by developing the high‐precision infrared cameras as well as new methods of image processing, biomedical thermography images have found a prominent position among the others. Furthermore, cancerous tissue can be affected by the laser. In this study, in order to treat the cancerous lesion identified by breast thermograms, the laser parameters are designed. The basis of controller designing is the obtained non‐linear indices. If the indices are moved from the chaotic behaviour to normal condition, the treating tissue is going from cancerous to a healthy condition and the treatment process is completed. Radiation frequency and the energy density of laser are designed as two key elements in the cancer treatment. In this study, the type I and type II fuzzy controllers are employed for the control strategies. Using the proposed closed‐loop control, the non‐linear indices of the cancerous lesion will be reduced during the treatment process. The simulation results on two datasets of breast thermograms indicate the superiority of type II fuzzy controller.Inspec keywords: closed loop systems, fractals, infrared imaging, tumours, fuzzy control, medical image processing, cancer, biological tissues, gynaecology, patient treatmentOther keywords: cancer tumours, breast thermograms, high‐precision infrared cameras, image processing, cancerous tissue, cancerous lesion, nonlinear indices, type II fuzzy controller, closed‐loop control, fuzzy controller design, breast cancer treatment, 2D fractal dimensions  相似文献   
17.
The synthesis of medium-long-medium type structured lipids (SL) by the interesterification of tricaprylin (TC) and trilinolenin (TLN), using selected commercial lipases from Rhizomucor miehei (Lipozyme RM IM) and Candida antarctica (Novozym 435) was investigated. Although the bioconversion yield (BY) for Lipozyme RM IM (24.7 %) was close to that for Novozym 435 (24.0 %), the initial enzyme activity was 6.3 μmol CLnC/g enzyme/min and 1.6 μmol CLnC/g enzyme/min, respectively. Lipozyme RM IM was subsequently selected for further investigation. The structural analyses of SL indicated that the major products were 1,3-dicapryl-2-linolenyl glycerol (CLnC) and 1(3)-capryl-2,3(1)-dilinolenyl glycerol (CLnLn). In order to optimize the BY, selected parameters were investigated. The experimental results showed that using hexane as the reaction medium, at an initial water activity (a w ) of 0.06, 10 mg solid enzyme/mL, substrate molar ratio of TC to TLN of 6:1 and a reaction time of 9 h, resulted in the highest BY (73.2 %). Using the optimized conditions, the effects of TLN concentration and other selective parameters, including the denaturation of the enzyme, controlling the a w and the addition of silica gel, on the mass productivity (P M), enzymatic productivity (P E) and volumetric productivity (P V ) of the interesterification reaction, were also investigated.  相似文献   
18.
In this paper, new polymer composites were synthesized by template copolymerization of aniline and metanilic acid in the presence of prepared melamine triacetic acid and poly(melamine-co-citric acid) as polyacids and dopants. The properties of the poly(aniline-co-metanilic acid) composites were studied by Fourier transform infrared, X-ray diffraction, scanning electron microscope, CV, and differential scanning calorimeter analysis. The four-point probe technique was used for evaluating the electrical conductivity of the composites. The scanning electron micrographs disclosed that the products had the morphology with agglomerated distorted spherical shapes with the average size of 40–50?nm. Also, the solubility of the composites had been improved notably in organic solvents.  相似文献   
19.
Designing dynamic pricing mechanisms that efficiently price resources in line with a provider's profit maximization goal is a key challenge in cloud computing environments. Despite the large volume of research published on this topic, there is no publicly available software system implementing dynamic pricing for Infrastructure as a Service cloud spot markets. This paper presents the implementation of a framework called Spot instance pricing as a Service (SipaaS) that supports an auction mechanism to price and allocate virtual machine instances. SipaaS is an open‐source project offering a set of web services to price and sell virtual machine instances in a spot market resembling the Amazon EC2 spot instances. Cloud providers, who aim at utilizing SipaaS, should install add‐ons in their existing platform to make use of the framework. As an instance, we provide an extension to the Horizon – the OpenStack dashboard project – to employ SipaaS web services and to add a spot market environment to OpenStack. To validate and evaluate the system, we conducted an experimental study with a group of 10 users utilizing the provided spot market in a real environment. Results show that the system performs reliably in a practical test environment. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
20.
The effect of hydrodynamic factors such as particle size, irrigation rate and aeration rate on the dissolution of uranium by Acidithibacillus ferrooxidans in column reactor was studied. Response surface methodology (RSM) was applied to predict the behavior of effective parameters and their interactions on the bioleaching process. Under the optimum conditions particle size of 5 mm, irrigation rate of 0.34 L/m2/min and aeration rate of 210 L/m2/min, the maximum value of uranium recovery was 63.85% for 19 days. The results from the statistical model and the experimental data showed good agreement and the most effective factor was the aeration rate. The interaction between particle size and irrigation rate has a negative effect and two other interactions have a positive effect on uranium recovery. Analysis of bioleaching residue confirmed the formation of K-jarosite on the surface of particles. The modified kinetic model at optimum conditions showed that cathodic ferric reduction is the rate controlling step on uranium bioleaching recovery.  相似文献   
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