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31.

Magnetohydrodynamics plays important role to manipulate the physiological fluids due to magnetic nature of physiological fluids. Magnetohydrodynamics pumps are a robust technology which provide more elegant and sustainable performance compared with conventional medical pumps. To study the effects of suspension of the nanoparticles (drugs) in physiological fluids (blood) flow are important in biomedical science and engineering. Motivated by such applications, an analytical approach is presented to study the nanoparticle shape effects on peristaltic transport of nanofluids in presence of magnetohydrodynamics in the present article. A two dimensional continuity, momentum and energy equations are considered to govern the present biophysical model. The governing equations are also linearized using lubrication theory where we consider the low Reynolds number and long wavelength approximations. Closed form solutions are obtained for axial velocity, axial pressure gradient, temperature, pressure rise, wall shear stress and stream function. The effects of three different type of shapes (bricks, cylinders, and platelets) of nanoparticles on peristaltic pumping characteristics and thermal characteristics are computed with the help of graphical illustrations. The interesting outcomes of this study are relevant to more realistic designs for ocular peristaltic pumps in drug delivery systems.

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32.
This study concentrates on the heat transfer characteristics and endoscope effects for peristaltic flow of a third order fluid. Two models of variable viscosity are chosen. Both perturbation and numerical solutions are obtained in each case. A comparative study is also made between the two solutions. The importance of pertinent flow parameters entering into the flow modeling is discussed.  相似文献   
33.
Vehicle type classification is considered a central part of an intelligent traffic system. In recent years, deep learning had a vital role in object detection in many computer vision tasks. To learn high-level deep features and semantics, deep learning offers powerful tools to address problems in traditional architectures of handcrafted feature-extraction techniques. Unlike other algorithms using handcrated visual features, convolutional neural network is able to automatically learn good features of vehicle type classification. This study develops an optimized automatic surveillance and auditing system to detect and classify vehicles of different categories. Transfer learning is used to quickly learn the features by recording a small number of training images from vehicle frontal view images. The proposed system employs extensive data-augmentation techniques for effective training while avoiding the problem of data shortage. In order to capture rich and discriminative information of vehicles, the convolutional neural network is fine-tuned for the classification of vehicle types using the augmented data. The network extracts the feature maps from the entire dataset and generates a label for each object (vehicle) in an image, which can help in vehicle-type detection and classification. Experimental results on a public dataset and our own dataset demonstrated that the proposed method is quite effective in detection and classification of different types of vehicles. The experimental results show that the proposed model achieves 96.04% accuracy on vehicle type classification.  相似文献   
34.
This paper presents an analytical study of magnetohydrodynamics and convective heat transfer of nanofluids synthesized by three different shaped (brick, platelet and cylinder) silver (Ag) nanoparticles in water. A two-phase nanoscale formulation is adopted which is more appropriate for biophysical systems. The flow is induced by metachronal beating of cilia and the flow geometry is considered as a cylindrical tube. The analysis is carried out under the low Reynolds number and long wavelength approximations and the fluid and cilia dynamics is of the creeping type. A Lorentzian magnetic body force model is employed and magnetic induction effects are neglected. Solutions to the transformed boundary value problem are obtained via numerical integration. The influence of cilia length parameter, Hartmann (magnetic) number, heat absorption parameter, Grashof number (free convection), solid nanoparticle volume fraction, and cilia eccentricity parameter on the flow and heat transfer characteristics (including effective thermal conductivity of the nanofluid) are examined in detail. Furthermore a comparative study for different nanoparticle geometries (i.e. bricks, platelets and cylinders) is conducted. The computations show that pressure increases with enhancing the heat absorption, buoyancy force (i.e. Grashof number) and nanoparticle fraction however it reduces with increasing the magnetic field. The computations also reveal that pressure enhancement is a maximum for the platelet nano-particle case compared with the brick and cylinder nanoparticle cases. Furthermore the quantity of trapped streamlines for cylinder type nanoparticles exceeds substantially that computed for brick and platelet nanoparticles, whereas the bolus magnitude (trapped zone) for brick nanoparticles is demonstrably greater than that obtained for cylinder and platelet nanoparticles. The present model is applicable in biological and biomimetic transport phenomena exploiting magnetic nanofluids and ciliated inner tube surfaces.  相似文献   
35.
Theoretical Foundations of Chemical Engineering - The developed industries are utilized natural waste fibers as a clean criteria device. This work utilized natural composite membranes in the...  相似文献   
36.
37.
The present article address the nanofluid flow with the interaction of shape factor and heat transfer in a vertical tube with temperature-dependent viscosity. Flow study has been done in a flexible tube with low Reynolds number (Re<<0 i.e and long wavelength (δ<<0 i.e assumption. Mathematica software is employed to evaluate the exact solutions of velocity profile, temperature profile, axial velocity profile, pressure gradient and stream function. The influence of heat source/sink parameter (β), Grashof number (Gr) and the viscosity parameter (α) and nanoparticle volume fraction (?) on velocity, temperature, pressure gradient, pressure rise and wall shear stress distributions is presented graphically. Three types of shape factor i.e cylinder platelets and bricks are discussed. Streamline plots are also computed to illustrate bolus dynamics and trapping phenomena which characterize peristaltic propulsion. It is seen that with an increment in Grash of number, Gr, nanofluid velocity is significantly increases i.e. flow acceleration is induced across the tube diameter. Once again the copper-methanol nanofluid in shape of platelets achieves the best acceleration.  相似文献   
38.
This paper presents a tangent hyperbolic fluid in a cylindrical coordinate system. The governing equations are simplified using long-wavelength and low Reynolds number approximations. The solutions of the problem in simplified form are calculated with three methods: (1)?perturbation method, (2)?homotopy analysis method, and (3)?shooting method. Comparison of the three solutions shows very good agreement among them. Pressure rise and frictional force are calculated with the help of numerical integration. Graphical results for pressure rise and frictional forces are presented to show the physical behavior of the Weissenberg number We, amplitude ratio ?, tangent hyperbolic power law index n, and radius ratio ?.  相似文献   
39.
PURPOSE: Food insecurity appears to be a growing problem for post-secondary students, but little study has been made of the 51 campus-based food banks that exist. In 2003-04, the University of Alberta Campus Food Bank (CFB) distributed hampers intended to supply four days of food to 630 unique clients, of whom 207 (32.8%) were children. The nutritional adequacy of food hampers and cost saving to students were evaluated in the current study. METHODS: Hampers prepared for one adult, and for one adult with one child, were nutritionally evaluated and scored for number of servings according to Canada's Food Guide to Healthy Eating. Two types of hampers were evaluated: those containing only non-perishable items, and those containing non-perishable and perishable items. Hamper contents were priced to establish the cost saving to students. RESULTS: The study revealed that a student with one child would receive up to 58.02 Canadian dollars worth of food in a hamper that contained perishable items. All hampers met the recommended minimum servings for each food group, but were very low in fat and protein from animal sources. CONCLUSIONS: Because students can obtain hampers only twice each month, the CFB is not the solution to food insecurity on campus. Awareness of the issue of post-secondary student food insecurity needs to be raised.  相似文献   
40.
Zinc biosorption characteristic of locally isolated Aspergillus flavus NA9 were examined as a function of pH, temperature, pulp density, contact time and initial metal ion concentration. The maximum zinc uptake was found to be 287.8 ± 11.1 mg g?1 with initial metal concentration 600 mg L?1 at initial pH 5.0 and temperature 30 °C. The equilibrium data gave good fits to Freundlich and Florry models with correlation coefficient value of 0.98. The contribution of the functional groups and lipids to zinc biosorption as identified by chemical pretreatment was in the order: carboxylic acids > hydroxyl > amines > lipids. The mechanism of biosorption was also studied using Fourier transform infrared (FTIR) spectrometry, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The biosorbent was regenerated using 0.01 M HCl with 83.3% elution efficiency and was reused for five sorption–desorption cycles with 23.5% loss in biosorption capacity. The order of co-cations showing increased inhibitions of zinc uptake by A. flavus NA9 was Pb > Cu > Mn > Ni. The biosorption assays conducted with actual paint industry effluents revealed efficiency of 88.7% for Zn (II) removal by candidate biomass.  相似文献   
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