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101.
102.
    
A new 4T2C pixel circuit formed on a silicon substrate is proposed to realize a high‐resolution 7.8‐μm pixel pitch AMOLED microdisplay. In order to achieve high luminance uniformity, the pixel circuit compensates its Vth variation of the MOSFET for the driving transistor internally by using self‐discharging method. Also presented are 0.5‐in Quad‐VGA and 1.25‐in wide Quad‐XGA microdisplays with the proposed pixel circuit.  相似文献   
103.
    
An economic performance evaluation scheme of historic buildings that consider the effect of structural renovation is proposed to provide information facilitating to the selection of reasonable renovation methods for preserving historic buildings. Ground motion scenarios, herein referred to as “lifecycle earthquake scenarios” in accordance with the previous research, were simulated to represent the annual maximum earthquake intensity data from the year of decision‐making until the end year of the building's lifetime. Additionally, the structural characteristics of historic buildings with masonry infill walls as part of the structure were analyzed under the “lifecycle earthquake scenarios.” Through a parametric analysis accounting for the change in structural characteristics and the repair costs in the lifecycle earthquake scenarios, the economic performance of historic buildings was calculated. Based on the results, the demand spectrum that satisfied the economic performance was obtained. This demand spectrum can provide the optimal structural renovation method to facilitate the building owner in making decisions regarding preservation.  相似文献   
104.
    
This work reports the template‐free fabrication of mesoporous Al2O3 nanospheres with greatly enhanced textural characteristics through a newly developed post‐synthesis “water‐ethanol” treatment of aluminium glycerate nanospheres followed by high temperature calcination. The proposed “water‐ethanol” treatment is highly advantageous as the resulting mesoporous Al2O3 nanospheres exhibit 2–4 times higher surface area (up to 251 m2 g?1), narrower pore size distribution, and significantly lower crystallization temperature than those obtained without any post‐synthesis treatment. To demonstrate the generality of the proposed strategy, a nearly identical post‐synthesis “water treatment” method is successfully used to prepare mesoporous monometallic (e.g., manganese oxide (MnO2)) and bimetallic oxide (e.g., CuCo2O4 and MnCo2O4) nanospheres assembled of nanosheets or nanoplates with highly enhanced textural characteristics from the corresponding monometallic and bimetallic glycerate nanospheres, respectively. When evaluated as molybdenum (Mo) adsorbents for potential use in molybdenum‐99/technetium‐99m (99Mo/99mTc) generators, the treated mesoporous Al2O3 nanospheres display higher molybdenum adsorption performance than non‐treated Al2O3 nanospheres and commercial Al2O3, thereby suggesting the effectiveness of the proposed strategy for improving the functional performance of oxide materials. It is expected that the proposed method can be utilized to prepare other mesoporous metal oxides with enhanced textural characteristics and functional performance.  相似文献   
105.
    
The circuit breaker is required to interrupt the current in order to prevent the spreading fault current. The reignition caused by the remaining high‐temperature gas in the opening of circuit breaker occurs. As this countermeasure, the external magnetic field application and blast gas to arc are used in order to decrease the arc temperature. It has been reported that the nonthermal equilibrium of arc is remarkable near the electrode and post arc. However, few reports have the analysis of separating electron and heavy particle momentums under consideration of the nonthermal equilibrium because the physical phenomena are complicated in the nonthermal equilibrium. In this paper, the electron and heavy particle velocity distribution under consideration of nonthermal equilibrium arc were analyzed. As a result, it is possible to quantify the electron and heavy particle velocity. The electron velocity distribution is dominant to the electric potential distribution. On the other hand, the heavy particle velocity distribution is dominant to the pressure gradient. Therefore, the difference between the electron and heavy particle velocity distribution was elucidated.  相似文献   
106.
    
Vacuum circuit breakers (VCBs) have been widely used in the medium distribution voltage range of 12–38 kV for more than half a century. Recent interest for them is because of the loss of vacuum in a vacuum interrupter (VI). Generally, the leakage is an improbable event during the expected lifetime of typically 20–30 years, while there are some reports that VIs beyond their expected lifetime have a significantly higher leakage rate. To keep the high reliability of middle voltage VCB, even for the high voltage VCB, it is necessary to develop the earlier detection method of vacuum leakage from VI. In the present study, an experimental setup with a partial discharge (PD) detecting system for detecting vacuum leakage from a test VI was constructed. The internal pressure of VI was arbitrarily regulated in the range of 0.02–100 Pa through an insulating tube using several valves. A detecting resistor of 1 kΩ was connected to a plane electrode located outside 115 mm away from VI to measure the PD current due to discharges inside the VI. A current transformer (CT) was also placed below the plane electrode. Sensors with different specification for PD detection, such as a transient earth voltage sensor, a horn antenna, and an acoustic emission sensor, were investigated and characterized. As a result of pressure dependence of PD inception voltage, it follows the left side of Paschen's Law in the pressure range more than 2.0 Pa, while no discharges occurred below 2.0 Pa. To analyze the PD charge and rise time from measured waveforms, the PD mechanism in the medium voltage range inside the VI was discussed. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
107.
    
As a solution for the large‐scale wind power transmission in a power system model in East Japan, multiterminal VSC‐HVDC systems are proposed to be installed in the system model. To evaluate the effectiveness of the systems, small‐signal stability‐constrained optimal power flow (SSSC‐OPF) analysis in mixed AC/multiterminal VSC‐HVDC systems is developed. It is revealed by SSSC‐OPF analysis that the system reinforced only by an AC system is exposed to unstable operations. In contrast, mixed AC/multiterminal VSC‐HVDC systems do not suffer from such unstable system operations. On top of that, the differences in multiterminal VSC‐HVDC systems with different configurations are also discussed. Different annual fuel costs and wind power hosting capacity results are obtained due to AC transmission line capacities and interarea oscillation modes. The best multiterminal VSC‐HVDC system among all simulated multiterminal VSC‐HVDC systems is also concluded. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
108.
    
We report enzymatic phosphorylation and additive-free ligation of DNAs containing unnatural C-nucleotide residues through the action of T4 polynucleotide kinase and T4 DNA ligase. The artificial units are each made up of an alkynyl deoxyribose component and one of the unnatural nucleobases D * , T * , G * , and C * , corresponding—from a viewpoint of hydrogen-bonding patterns—to natural A, T, G, and C, respectively. Phosphorylation progressed quantitatively at the 5′-end in the cases of all of the artificial units in the chimeric DNAs. Ligation also smoothly progressed at the 5′-end in the cases of the D* and G* nucleotide residues, but only negligibly in those of their T* and C* counterparts. Chemical redesign of the last two units successfully improved the ligation efficiency, so that enzymatic ligation worked well for all of the artificial units in every 3′-natural ⋅ 5′-artificial, 3′-artificial ⋅ 5′-natural, and 3′-artificial ⋅ 5′-artificial terminal combination at the nicks.  相似文献   
109.
110.
    
Heterostructured materials are interesting because they may combine two or more material building blocks that together generate new types of heterointerfaces with unusual properties. Using them to construct large‐scale 3D frameworks further extends their utility in electrochemical applications because it exposes more interfaces and active sites. In this study, electrostatic interactions are used to wrap polyhedra particles of zeolitic imidazolate frameworks with graphene oxide (GO) nanosheets to prepare the composite structure. Pyrolyzing this structure generates a 3D porous carbon framework (PCF) composed of polyhedral‐shaped hollow carbon coated with reduced GO. The size of the polyhedral macropores can be adjusted from nanometer scale to micrometer scale. The PCFs generate a continuous network of heterostructured carbon with a large surface area and large pore volumes that are particularly useful as porous electrodes in lithium–sulfur batteries. The PCF/S composite electrode exhibits a high discharge capacity of 1151 mAh g−1 at 1 C and a low capacity decay of 0.035% per cycle after 650 cycles.  相似文献   
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