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21.
Carbon control policies, competitiveness, and border tax adjustments   总被引:1,自引:0,他引:1  
Several propositions have recently been made to use border tax adjustments (BTAs) to address the loss of competitiveness induced by unilateral stringent domestic pollution control policies. This paper explores in a general equilibrium framework the sectoral and welfare implications of a unilateral domestic GHG control policy combined with a BTA scheme. Using the Canadian economy as an illustration, we assess the extent to which BTAs achieve their objectives and analyze the impacts of different methods of recycling the BTA proceeds to support domestic industries. Our simulation results suggest that imposing BTAs on the imports of non-fossil and energy-intensive products reduces or removes completely the negative competitiveness impacts that domestic industries suffer from. The use of the proceeds of the BTAs to support domestic energy-intensive industries improves their competitiveness and, more importantly, in some cases, overprotects them, as it allows them to even increase their output in comparison to the benchmark without emissions control. Our results also shed light on the existence of heterogeneity in the composition of energy-intensive industries as far as the recycling method of the BTA proceeds is concerned. Energy-intensive industries that are more oriented toward the domestic market are better off with the recycling of the BTA proceeds towards gross output than towards exports alone. Finally, abstracting from the environmental benefits of reduced emissions, we find that a BTA entails a higher welfare cost to households.  相似文献   
22.
For images with poor and non-uniform illumination, adaptive thresholding is required to separate the objects of interest from the background. In this paper a new approach to create an adaptive threshold surface is proposed to segment an image. The technique is inspired by the Yanowitz’s method and is improved upon by the introduction of a simpler and more accurate threshold surface. The method is tested on several images of different patterns with varying illumination and the results are compared to the ones produced by a number of adaptive thresholding algorithms. In order to demonstrate the effectiveness, the proposed method had been implemented in medical and document images. The proposed method compares favorably against those using watershed and morphology in medical image and favorably against variable threshold and adaptive Otsu’s N-thresholding for document image.  相似文献   
23.
The aim of this study was to investigate the performance of UHMWPE/HDPE-reinforced kenaf, basalt and hybrid kenaf/basalt composites. Mechanical testing of these samples was carried out such as tensile, flexural (three-point bending) and an impact test (Charpy). Pure resin (UHMWPE/HDPE) samples were tested and compare with reinforced 10% weight fraction of kenaf, basalt and hybrid kenaf/basalt samples to identifying their contribution and potential in this new composite material. UHMWPE/ HDPE sample was produced in constant ratio 60:40 respectively via extrusion process. Basalt reinforced UHMWPE/HDPE generates the highest elastic modulus result compared to kenaf and hybrid kenaf/basalt as a reinforcement material. The tensile results of kenaf reinforcement UHMWPE/HDPE samples are significantly higher (20%) than pure blend resin, which is an indication for good performance of kenaf, basalt and hybrid kenaf/basalt to be used in UHMWPE/HDPE-blend polymers. The flexural and Charpy strengths show the drawback results, where performance of polymer is reduced 5% with the absence of kenaf. It can be concluded that kenaf, basalt and hybrid kenaf/basalt fiber successfully increase the UHMWPE/HDPE blends performance especially under tensile loading.  相似文献   
24.
A method for surface quality evaluation and temperature monitoring of the billet in continuous casting is considered in this paper. This method uses the difference between the measured and the filtered temperature computed using an adaptive support vector machine method. The temperature field, measured by an infrared camera, is affected by an important noise called calamine (a metal oxide generated during the cooling process). The quality of the billet’s surface temperature is connected to the secondary cooling behavior, and therefore an evaluation of the calamine effect is needed. Methods such as soft sensing and adaptive support vector machine are used for a global evaluation of calamine intensity on the monitored area of the billet in continuous casting. This kind of approaches is applied in continuous casting process for constructing a complementary condition monitoring system, which allows an online calamine evaluation. Simulation results, based on the measured surface temperature and the adaptive support vector machine analysis, showed that this new combined approach is easily implementable and gives good results when applied online.  相似文献   
25.
Hydroxide sludge (HS) is the main by-product of drinking water production stations. In our work, we have promoted the valorization of these sludge, we convert it into activated carbon to serve as a support as a heterogeneous Fenton catalyst for reactive blue 19 (RB 19) degradation. The HS and Fe/HS-300 were characterized by means of SEM, EDX-ray, FTIR and XRD analysis. RB 19 and TOC removals were 92% and 41% respectively in optimal condition. More importantly, Fe/HS-300 exhibited an excellent stability and low Fe ion leaching (0.2–0.7mg/L), it was recycled 6 runs still maintaining the same efficiency.  相似文献   
26.
A number of correlation equations describing the performance characteristics of round tube and plate fin have been published in the open literature. However, many of these correlations are restricted to flat finned heat exchangers and a limited number of geometrical configurations. In this study, 28 heat exchanger samples were tested in an open circuit thermal wind tunnel over a velocity range of 1 to 20 m/s for a number of geometries. The geometrical variations include the number of tube rows, fin thickness and the spacing between fins, rows and tubes. Both flat and corrugated fins were tested and the results were correlated in terms of j and f factors as a function of Reynolds number and the geometrical parameters of the heat exchangers. An important feature of this correlation is the novel way in which the geometric parameters are expressed in the correlation. Ratios of these parameters are derived from consideration of the physics of the flow and heat transfer in the heat exchangers. This results in a more accurate and physically meaningful correlation which can be applied to a broader range of geometries. The correlation was validated against test data in the literature for round tube and plate fin with good agreement. It was found that the fin type affects the heat transfer and friction factor, and that the number of tube rows has a negligible effect on the friction factor. The number of tube rows effect was found to be influenced by the fin and tube geometries as well as the Reynolds number.Un certain nombre d'équations pour des caractéristiques du rendement des échangeurs de chaleur à tubes ronds plaques à ailettes ont été publiés dans le littérature. Cependant, dans bien des cas, ces corrélations se limitent aux échangeurs à ailette plate dans un nombre limité de configurations géométriques. Dans cette étude, 28 échangeurs de chaleur ont été testés utilisant une soufflerie à circuit ouvert avec une vitesse d'air de 1 à 20 m/s pour plusieurs formes géométriques. Les variations géométriques portaient sur le nombre de rangées de tubes, l'épaisseur des ailettes et la distance séparant des ailettes, des rangées et des tubes. Les ailettes plates et ondulées ont été testées et les corrélations en termes de facteurs j et f en fonction du nombre de Reynolds et les paramètres géométriques des échangeurs de chaleur. Un aspect important de cette corrélation est le façon originale d'exprimer des paramètres géométriques. Les rapports de ces paramètres sont obtenus à partir des flux et transferts de chaleur dans des échangeurs de chaleur. Ce procedé permet d'obtenir une corrélation plus précise et utilé qui s'applique à une gamme de formes géomátriques plus large. La corrélation a été validée en fonction des données concernant des échangeurs à tube et à plaque à ailettes dans la littérature: les données expérimentales et théoriques concordent bien. On a montré que le type d'ailette exerce une influence sur le transfert de chaleur et le facteur de frottement. Cependant, le nombre de rangées de tubes a un effet negligeable sur le coéfficient de frottement. On a démontré que l'effet nombre de rangées de tube est influencé par les géométries des ailettes et des tubes ainsi que par le nombre de Reynolds.  相似文献   
27.
We present here two methods of analysis of the complex moving waveguide. One approach is a numerical technique based on Davidenko's method, the other is a perturbation method. Numerical results by Davidenko's method are compared with these obtained from the perturbation method. It is found that the results of the perturbation method are in a good agreement with the numerical one. A comparative study of the propagation and attenuation characteristics of the stationary and moving waveguides has also been investigated and discussed. These results could be used in designing many optical moving sensors.  相似文献   
28.
Thermally sprayed ceramic coatings such as plasma-sprayed alumina exhibit a composite microstructure actually due to the presence of defects such as pores, inter-lamellar and intra-lamellar cracks. These second phase-typed features influence the mechanical behaviour of the coating dramatically. In this study, a microstructure simulation of plasma-sprayed alumina was developed for the optimizing of component properties such as electrical tool used in the oil industry. This approach consisted of a finite-element analysis of mechanical properties from simulated microstructures. Several composite microstructures were tested from air plasma spraying of alumina. Various degrees of porosity and cracks could be obtained from different spraying conditions. Every composite microstructure was studied using a quantitative image analysis of scanning electron microscope (SEM) cross-sections. A finite-element model based on the actual microstructure was developed. First, two-dimensional (2D) finite elements meshes were created from SEM images of microstructures. Then, in order to have a realistic representation of the three-dimensional (3D) microstructure, pictures were obtained using X-ray microtomography. Volume tetrahedral grids were generated to simulate the properties of alumina coatings. This work studies the contribution of every part of the alumina coating to the final properties and shows potentials and limitations of the 2D and 3D computational approach.  相似文献   
29.
This work aims to evaluate the potential risks of incidents in nuclear research reactors. For its development, two databases of the International Atomic Energy Agency (IAEA) were used: the Research Reactor Data Base (RRDB) and the Incident Report System for Research Reactor (IRSRR). For this study, the probabilistic safety analysis (PSA) was used. To obtain the result of the probability calculations for PSA, the theory and equations in the paper IAEA TECDOC-636 were used. A specific program to analyse the probabilities was developed within the main program, Scilab 5.1.1. for two distributions, Fischer and chi-square, both with the confidence level of 90 %. Using Sordi equations, the maximum admissible doses to compare with the risk limits established by the International Commission on Radiological Protection (ICRP) were obtained. All results achieved with this probability analysis led to the conclusion that the incidents which occurred had radiation doses within the stochastic effects reference interval established by the ICRP-64.  相似文献   
30.
The fallen yellowish bamboo leaves around bamboo crops are always overlooked even though they contain high silica in their ash. Bamboo leaf valorization consequently has the potential to be a green process for synthesizing amorphous silica. Unfortunately, the optimum process parameters have not been widely disclosed. Hence, this study intends to optimize the synthesis of amorphous bio-silica nanoparticles from bamboo leaves using Box–Behnken design (BBD). Bamboo leaves were initially washed with HCl, followed by combustion at 700°C, and then ash washing, extraction of silica with NaOH (sol–gel method), gelation, and drying. According to the results, optimum conditions occur under no acid washing of leaves, solvent-to-feed ratio = 5 mL/g, and extraction duration = 1.5 h. The optimum conditions give the highest purity (94.1 wt.%) and yield (42.33%) as well as the highest surface area (328.61 m2/g), smallest pore diameter (8.69 nm), and largest pore volume (0.71 cc/g) of bio-silica nanoparticles. Furthermore, bio-silica nanoparticles are amorphous, spherical-shaped aggregates, and have a white powdered colour.  相似文献   
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