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91.
Multimedia Tools and Applications - Corneal reflection extracted from an eye image identifies the relationship between the subject of the image and the scene in front of the subject. The...  相似文献   
92.
Metal embedded grid artificial dielectric resonator antennas (GDRAs) fed by different coplanar waveguide (CPW) feeding techniques at mm‐wave frequencies are investigated in detail. GDRAs involve embedding tall nickel metal inclusions in polymethyl‐methacrylate (PMMA) using deep X‐ray lithography and electroforming, which dramatically increases the effective permittivity of the polymer up to 5‐6 times and results in miniaturized antenna structures operating at millimeter‐wave frequencies. The options for different coplanar waveguide (CPW) feeding at 22.6‐26.6 GHz and 26.6‐29.3 GHz are studied by applying a thin 300 μm PMMA layer between the feed layer and metal inclusions of the GDRA to avoid short‐circuiting the underneath feed line structures. In addition, this results in a GDRA structure that improves the impedance bandwidth up to 16.26%, while providing a maximum realized gain of 7.2 dBi across the frequency band with excellent broadband patterns and ?18 dB cross‐polarization levels.  相似文献   
93.
Neural Computing and Applications - This work offers an approach to aerial image classification for use in remote sensing object recognition, image processing and computer vision. Sparse coding...  相似文献   
94.
Hydrogen generation from electrocatalytic water splitting is of supreme significance for resolving energy crisis and environmental concerns. However, developing earth-abundant, efficient, and durable electrocatalyst for high-performance hydrogen evolution and complete water splitting catalysis is a rare instance. We present here the first demonstration of unique copper tellurides nano-structures (CuTe-NS) based electrocatalyst executing HER with high activity and remarkable stability. CuTe-NS based electrocatalysts grown over conductive NiF via drop-casting approach and employed for HER, while achieving a current decade and a current density of 100 mA/cm2 just at 0.25 V vs. RHE and 0.27 V vs. RHE, which is comparable to the benchmark Pt/C based HER catalyst. The catalyst demonstrates well-balanced kinetic behavior, low Tafel slope of 36 mV/dec, low charge transfer resistance of 1.71 Ω, high roughness factor, and remarkable stability for more than 60 h of electrolysis. Furthermore, post-catalysis characterizations demonstrate no change in catalyst integrity, morphological, and structural attributes even after many hours of electrolysis which show sustainable behavior of catalyst for long term HER activity. Because of electrochemical and structural stabilities after long term electrolysis experiments, accessible method of preparations, and cost-effectiveness, the catalysis is highly encouraging for real-life applications.  相似文献   
95.
An imbalanced current distribution is often observed in cables of parallel batteries, which may limit the release of the energy and power in the battery pack. Hence, it is very important to analyze the homogeneous current distributions within parallel battery batteries and explore the effect on the state of charge and energy loss. Initially, it can be found that a battery near the load will experience a large local current under higher discharge rate. With the discharge, the current distribution will show a surge wave distribution, and the peak is gradually shifted backwards. As discharge continues, local current profile in segments will have different development trends, while current profile with lower initial current values increase, which leads to an entirely different form of current distribution with the initial stage of discharge. The current profile moves in a wavelike form transmission when the total discharge rate is low. The higher the current rate, the more divergent the current distribution. The state of charge distribution is also nonuniform, clearly indicating underutilization of active materials, which will further aggravate the nonuniformity of the local current distribution in the parallel battery pack.  相似文献   
96.
Melting heat transfer and non-Darcy porous medium effects in MHD stagnation point flow toward a stretching surface of variable thickness are addressed. Brownian motion and thermophoresis in nanofluid modeling are retained. Zero mass flux condition for concentration at surface is imposed. The problem of ordinary differential system are analyzed numerically through shooting technique. Graphically results of various physical variables on the velocity, temperature and concentration are studied. Skin friction coefficient local Nusselt number and Sherwood number are also addressed through tabulated values. The results described here illustrate that the velocity field is higher via larger melting parameter. However reverse situation is examined for Hartman number. Moreover the influence of thermophoresis parameter on temperature and concentration is noted similar.  相似文献   
97.
This work reports the enhancing effect of a highly cost effective and efficient metal, Fe, incorporation to Co or Ni based Mo/Al_2O_3 catalysts in the oxidative desulfurization(ODS) of dibenzothiophene(DBT) using H_2O_2 and formic acid as oxidants. The influence of operating parameters i.e. reaction time, catalyst dose, reaction temperature and oxidant amount on oxidation process was investigated. Results revealed that 99% DBT conversion was achieved at 60 °C and 150 min reaction time over Fe–Ni–Mo/Al_2O_3. Fe tremendously enhanced the ODS activity of Co or Ni based Mo/Al_2O_3 catalysts following the activity order: Fe–Ni–Mo/Al_2O_3 NFe–Co–Mo/Al_2O_3 NNi–Mo/Al_2O_3 NCo–Mo/Al_2O_3, while H_2O_2 exhibited higher oxidation activity than formic acid over all catalyst systems. Insight about the surface morphology and textural properties of fresh and spent catalysts were achieved using scanning electron microscopy(SEM), X-ray diffraction(XRD), energy dispersive X-ray(EDX)analysis, Atomic Absorption Spectroscopy(AAS) and BET surface area analysis, which helped in the interpretation of experimental data. The present study can be deemed as an effective approach on industrial level for ODS of fuel oils crediting to its high efficiency, low process/catalyst cost, safety and mild operating condition.  相似文献   
98.
Inulin as a heterogeneous blend of fructose polymers is diversely found in nature primarily as storage carbohydrates in plants. Besides, inulin is believed to induce certain techno-functional and associated properties in food systems. Inulin owing to its foam forming ability has been successfully used as fat replacer in quite a wide range of products as dairy and baked products. Furthermore, it is known to impart certain nutritional and therapeutic benefits that extend apart to improve health and reduce the risk of many lifestyle related diseases. Additionally, as a functional ingredient, Inulin has been adopted in various efficacy studies involving animal and human studies to function as a prebiotic, in promoting good digestive health, influencing lipid metabolism and has some beneficial roles in ensuring optimum levels of glucose and insulin. This review article is an attempt to present a comprehensive overview on both techno-functional and therapeutic potential of inulin.  相似文献   
99.
On the account of industrial and technological applications, the enhancement of energy by inserting nanoparticles is a hot topic in the present century. Therefore, the current analysis presents a theoretical analysis regarding the flow of electrically conducted Maxwell nanofluid over a stretching surface in the presence of the gyrotactic microorganism. In addition, the influence of thermal conductivity and Arrhenius activation energy are considered. By using the apposite transformation, the system of contemporary partial differential expressions is first converted into nonlinear ordinary differential system. The set of these transmuted equations is solved with the help of the shooting method. Reliable results are obtained for the velocity profile, temperature, motile microorganism density and concentration. It is evaluated that by increasing the value of bioconvection Peclet and Lewis numbers, the microorganism distribution exhibited diminishing behavior. These results may be useful in improving the efficiency of heat transfer devices and microbial fuel cells.  相似文献   
100.
Traditionally, in order to simplify the bubble growth process in a polymer melt, an isothermal model is typically used. In fact, the temperature of the polymer melt is changing during the foaming process. In order to accurately study the growth mechanism of bubbles in polymer melts, we build a physical and mathematical model of bubble growth in a polymer melt under nonisothermal conditions. The parameters of pressure, zero-shear viscosity, relaxation time, Henry's constant, diffusion coefficient, and surface tension were determined. The fourth-order Runge–Kutta method was used to solve the nonisothermal bubble model in the polymer melt. A computational program is developed to find the dimensional change during the bubble growth process, and the correctness of the model is verified. The nonisothermal growth mechanism of and factors influencing bubbles in the polymer melt are analyzed. Combined with the design of experiment (DOE) analysis method, the transfer function of the bubble radius and the maximum growth rate of bubbles with the process parameters were obtained, such as cooling rate, system pressure, and gas concentration. The results show that system pressure has the most significant effect on bubble growth. At the same time, a bubble growth prediction model is built, which can be used to predict the growth of bubbles. Through optimization analysis, it can be used to control the growth of bubbles. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47210.  相似文献   
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