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991.
In this paper we propose an algorithm to establish a DiffServ-Aware Multicast Tree (DAMT) in a mobile IPv6 network. We first use the modified Prim’s algorithm to construct the Maximum Available Bandwidth Map (MABM) in a mobile IPv6 network. Then, both the extended multicast routing table stored in each Edge Router (ER) and the Interface QoS Table (IQT) stored in each Core Router (CR) are created and used to construct a DAMT. Finally, the constructed MABM can be rearranged (R-MABM) in order to keep the same QoS as a Mobile Node (MN) had in the home network when the MN has moved to a new ER. The proposed algorithm solves the architectural conflicts for the integration of multicasting support in the Diffserv network as well as the problems of the Neglected Reservation Sub-tree (NRS) and receiver heterogeneity. It also solves a MN’s QoS requirement when the MN moves from one network to another. Simulation results indicate that the proposed algorithm offers better performance than existing approaches in average delay, average packet loss rate, average throughput, the number of control overhead, the usage of bandwidth, the amount of saved link bandwidth, and the accumulated time to find a feasible path, especially in the case where the number of new join MN is large and traffic loads are heavy.  相似文献   
992.
We propose a novel Sorted Switching Median Filter (i.e. SSMF) for effectively denoising extremely corrupted images while preserving the image details. The center pixel is considered as “uncorrupted” or “corrupted” noise in the detecting stage. The corrupted pixels that possess more noise-free surroundings will have higher processing priority in the SSMF sorting and filtering stages to rescue the heavily noisy neighbors. Five noise models are considered to assess the performance of the proposed SSMF algorithm. Several extensive simulation results conducted on both grayscale and color images with a wide range (from 10% to 90%) of noise corruption clearly show that the proposed SSMF substantially outperforms all other existing median-based filters.  相似文献   
993.
The vertical organic space-charge-limited transistor made of P3HT and small-molecule phosphorescent organic light-emitting diode (OLED) are made on two separate glass substrate by blade coating, then soldered vertically together by tin balls with 40 μm diameter. The soldering is done by hot wind of 150 °C for 5 min Contact resistance is only 10 Ω. The vertical transistor is annealed at 150 °C for 5 min before soldering to enhance the output current up to 25 mA/cm2 and give high thermal stability. Both OLED and the annealed vertical transistor are not affected by the soldering process. The vertical transistor has 1/4 of the OLED area and turns on the bottom-emission white OLED up to 300 cd/m2 and orange OLED up to 600 cd/m2. The entire operation is within 8 V. OLED and transistor array can therefore be made on separate glass substrates then soldered together to form the display.  相似文献   
994.
A validation study using the National Renewable Energy Laboratory (NREL) Phase VI wind turbine is presented. The aerodynamics simulations are performed using the finite element arbitrary Lagrangian–Eulerian–variational multiscale formulation augmented with weakly enforced essential boundary conditions. In all cases, the rotor is assumed to be rigid and its rotation is prescribed. The rotor‐only simulations are performed for a wide range of wind conditions, and the computational results compare favorably with the experimental findings in all cases. The sliding‐interface method is adopted for the simulation of the full wind turbine configuration. The full‐wind‐turbine simulations capture the blade–tower interaction effect, and the results of these simulations are also in good agreement with the experimental data. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
995.
The versatility of a fluoro‐containing low band‐gap polymer, poly[2,6‐(4,4‐bis(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b;3,4‐b’]dithiophene)‐alt‐4,7‐(5‐fluoro‐2,1,3‐benzothia‐diazole)] (PCPDTFBT) in organic photovoltaics (OPVs) applications is demonstrated. High boiling point 1,3,5‐trichlorobenzene (TCB) is used as a solvent to manipulate PCPDTFBT:[6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) active layer morphology to obtain high‐performance single‐junction devices. It promotes the crystallization of PCPDTFBT polymer, thus improving the charge‐transport properties of the active layer. By combining the morphological manipulation with interfacial optimization and device engineering, the single‐junction device exhibits both good air stability and high power‐conversion efficiency (PCE, of 6.6%). This represents one of the highest PCE values for cyclopenta[2,1‐b;3,4‐b’]dithiophene (CPDT)‐based OPVs. This polymer is also utilized for constructing semitransparent solar cells and double‐junction tandem solar cells to demonstrate high PCEs of 5.0% and 8.2%, respectively.  相似文献   
996.
The effects of dimerumic acid (DMA) on apoptosis prevention and insulin production in the glucose metabolite methylglyoxal (MG)-treated pancreatic RINm5F cells were evaluated. MG was found to induce apoptotic signal molecules mediated by oxidative stress in RINm5F cells, including caspase-3 and caspas-9, resulting in cell death and decreasing insulin production. In addition, DMA elevated insulin synthesis via up-regulating mammalian homologue of avian MafA/L-Maf (Maf-A) and pancreatic-duodenal homeobox-1 (PDX-1) and inhibited MG-mediated CCAAT/enhancer binding proteins-β (C/EBPβ) expression, which is a negative regulator for insulin production. Nuclear factor-erythroid2-related factor 2 (Nrf2) is essential for antioxidant responsive element (ARE)-mediated induction. Results indicated that nuclear translocation of Nrf2 was promoted by DMA in MG-treated RINm5F cells to increase heme oxygenase-1 (HO-1) and glutamate-cysteine ligase (GCL) expressions. We confirmed that DMA protected PDX-1, Maf-A, and insulin production against MG-induced oxidative stress mediating by Nrf2 in Nrf2-knockdown RINm5F cells. These results suggest that DMA exerts antioxidative ability to attenuate MG-induced pancreatic cell damage and elevates insulin level to improve diabetes.  相似文献   
997.
998.
Mycotoxins are secondary metabolites produced by fungi, such as Fusarium, Penicillium, and Aspergillus, which are toxic to humans with high risk factors and pose a significant threat to human health. This study was focused mostly on well-known mycotoxins, such as aflatoxins (AFB1, AFB2, AFG1 and AFG2), fumonisin (FB1, FB2), deoxynivalenol (DON), zearalenone (ZON), ochratoxin A, T-2 and HT-2, in grains. The multi-mycotoxin methods developed in this study utilise an analysis of mycotoxin through liquid chromatography tandem mass spectrometry (LC-MS/MS), which can significantly improve sample analysis efficiency. The Myco6in1? immunoaffinity column was used for purification to reduce interference from the substrate. Gradient separation to obtain the best peak shift was conducted using solvent with 0.1 % formic acid in deionised water and methanol, and gradient separation was performed on an ACQUITY BEH C18 column chromatograph. The recovery rate test for each toxin using substrates such as rice, peanut, wheat and maize mostly indicated good average recovery rates between 70 % and 120 % and the coefficient of variation mostly under 15 %. The limits of quantification (LOQ) identified by this method are less than 5 ng/g in most toxins, except for 20 ng/g in FB1and FB2. This method can rapidly and simultaneously analyse 11 mycotoxins in 9 min. It can be applied for the practical examination of mycotoxins in food to protect public health.  相似文献   
999.
This paper presents two low power UWB LNAs with common source topology. The power reduction is achieved by the current-reused technique. The gain and noise enhancement of the proposed circuit is based on an output buffer which is used by a common source amplifier with shunt–shunt feedback. Chip1 is an adopted T-match input network of 50 Ω matching in the required band. Measurements show that the S11 and S22 are less than −10 dB, and the maximum amplifier gain S21 gives 9.7 dB, and the noise figure is 4.2 dB, the IIP3 is −8.5 dBm, and the power consumption is 11 mW from 1.1 V supply voltage. The input matching of chip2 is adopted from a LC high pass filter and source degenerated inductor. The output buffer with the RC-feedback topology can improve the gain, increase the IIP3, restrain the noise, improve the noise figure and decrease the DC power dissipation. Measurements show 13.2 dB of power gain, 3.33 dB of noise figure, and the IIP3 is −3.3 dBm. It consumes 9.3 mW from 1.5 V supply voltage. These two chips are implemented in a 0.18 μm TSMC CMOS process.  相似文献   
1000.
This study explores how ultra high-speed processing parameters affect the melt flow length and tensile strength of thin-wall injection molded parts. A spiral shaped mold with a specimen thickness of 0.4 mm and a width of 6 mm was first constructed to test the melt flow length as an index of process capability for ultra high-speed injection molding. It was observed that the flow length increases with increasing injection speed. High-density polyethylene (HDPE) tensile test specimens with different thicknesses (0.6 mm and 2 mm) were also molded for tensile tests. Both single gate and double gates were used to form parts without and with weldlines. Injection molding trials were executed by systematically adjusting related parameters setting including mold temperature, melt temperature, and injection speed. The parts’ tensile strengths were measured experimentally. It was found that tensile strengths of 0.6 mm thick parts both with and without weldlines were higher than those of 2 mm thick parts. The tensile strength of 0.6 mm thick specimens increases with increasing mold temperature, melt temperature and injection speed, whereas tensile strength in 2 mm thick specimens was only weakly dependent on the corresponding processing parameters. Furthermore, 0.6 mm thick specimens with weldlines had tensile strengths lowered about 9.6% compared to parts without weldlines. For 2 mm thick part the corresponding reduction is 4.3%.  相似文献   
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