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961.
It was reported that the innovation of “An Intelligent Catalyst” which has the self-regenerative function of Pd, and the development for application to the Japanese ULEV standard. In this paper, the answer for a left-behind big question was replied to. It was whether the self-regenerative function is unique to Pd or it can happen to Rh and Pt. X-ray absorption fine structure measurement at SPring-8 was used effectively to solve this question. The attempt succeeded in the development of “A Super Intelligent Catalyst” which Rh and Pt can be also realized through the solid solution and segregation as well as Pd in a perovskite crystal.  相似文献   
962.
The effects of surface modification of lead lanthanum Zirconate titanate (PLZT) powder on sintering and transparency were investigated by sintering hydrophobic powders modified with various alcohols. When alcohols with longer chain lengths were used for surface treatment, aggregation forces among the particles were reduced, resulting in dense, highly transparent ceramics.  相似文献   
963.
964.
A multicolor photodetector based on the heterojunction of n‐Si(111)/TiO2 nanorod arrays responding to both ultraviolet (UV) and visible light is developed by utilizing interface engineering. The photodetector is fabricated via a consecutive process including chemical etching, magnetron sputtering, hydrothermal growth, and assembling. Under a small reverse bias (from 0 to ≈?2 V), only the photogenerated electrons in TiO2 are possible to tunnel through the low barrier of ΔEC, and the device only responses to UV light; as the reverse bias increases, the photogenerated holes in Si also begin to tunnel through the high barrier of ΔEV. As a result, the device is demonstrated to have the capacity to detect both UV and visible lights, which is useful in the fields of rapid detection and multicolor imaging. It has been also observed that the crystal orientation of Si affects the characteristics of bias‐controlled spectral response of the n‐Si/TiO2 heterojunctions.  相似文献   
965.
Japan Atomic Energy Research Institute carries out research and development on accelerator-driven system (ADS) to transmute minor actinides and long-lived fission products in high-level radioactive waste. The system is composed of high intensity proton accelerator, lead-bismuth spallation target and lead-bismuth cooled subcritical core with nitride fuel. About 2500 kg of minor actinide is loaded into the subcritical core. Annual transmutation amount using this system is 250 kg with 800 MW of thermal output. This transmutation amount corresponds to the amount of minor actinides produced from 10 units of 1GWe power reactors annually. A superconducting linear accelerator with the beam power of 20–30 MW is connected to drive the subcritical core. To maximize the transmutation efficiency, the nitride fuel without uranium, such as (Np, Am, Pu)N, is selected. The nitride fuel irradiated in the ADS is reprocessed by pyrochemical process followed by the re-fabrication of nitride fuel. Many research and development activities are under way and planned in the fields of subcritical core design, spallation target technology, lead-bismuth handling technology, accelerator development, and minor actinide fuel development. Especially, to study and evaluate the feasibility of the ADS from physics and engineering aspects, the transmutation experimental facility (TEF) is proposed under a framework of the High-Intensity Proton Accelerator Project.  相似文献   
966.
This paper attempts to discover the invariant features in a whole-body dynamic task under perturbations. Our hypothesis is that the features are useful both for execution and recognition of a task, and have their origin in human embodiment.

For the sake of concreteness, we focus on a particular task named “Roll-and-Rise” motion, and carried out a multi-approach investigation. First, an analysis of motion capture data of human performance is presented to show its invariant features. Next, we show that such invariants emerge from the underlying physics of the task, using simulation data. These invariants are actually useful for generating robot motion, which has been successfully realized with an adult-size real humanoid robot. The experimental data are analyzed to confirm the temporal localization of invariant features. Lastly, we present a psychological experiment which confirms that these timings are actually important points where human observers extract crucial information about the task.  相似文献   

967.
Abstract— We studied the influence of x‐ray irradiation on the doped europium ion in BaMgAl10O17 (BAM) by x‐ray absorption fine structure measurement and x‐ray diffraction. We found that x‐ray irradiation promoted oxidation of doped europium and fading emissions. However, no difference was found in x‐ray diffraction patterns before and after x‐ray irradiation. We concluded that the fading of BAM after x‐ray irradiation was mainly caused by oxidation of the doped europium in the BAM.  相似文献   
968.
Previously, the authors have published work describing a pure Ni fixed point within alumina crucibles. The success of this study stimulated working with the Ni–Ag monotectic point in alumina crucibles. Similar to eutectic points, the Ni–Ag monotectic temperature is an invariant point but it differs from a eutectic reaction in such a way that the monotectic phase change takes place from Ni–Ag liquid solution to Ni–Ag solid solution and Ag rich Ni–Ag liquid solution. In the phase diagram references, the Ni–Ag monotectic phase transition temperature is assigned to be about 20 \(^{\circ }\)C below the pure Ni melting/freezing point. As is the case for pure Ni, mechanical stability is one of the concerns. Therefore, proper cell design is necessary to avoid breakage of the alumina crucible. The techniques used for the fabrication and measurement of the pure Ni cell were applied to the Ni–Ag cell as well. The cells have been successfully fabricated and the temperature measurement at the fixed point was carried out for more than 20 thermal cycles in total. A Pt/Pd thermocouple was used to measure the temperature and was calibrated from the tin point to the gold point to measure the ITS-90. Freezing plateaus are realized with the technique of “recurrent offset freezing method with reserved solid”. The duration of each freezing plateau is a minimum of 30 min. The monotectic transformation temperature for the best performed cell is determined as 1428.27 \(^{\circ }\)C with a combined uncertainty of ±0.06 \(^{\circ }\)C (\({k}=1\)).  相似文献   
969.
微波等离子体法制备氮化钛/氧化钛催化剂   总被引:1,自引:0,他引:1  
用微波等离子体法以N_2:H_2=1:1气体比例制取了氮化钛/氧化钛催化剂。所得催化剂呈现出1,3-丁二烯加氢活性和甲醇水溶液中氢气生成的光催化活性。  相似文献   
970.
Large size of capacitors is the main hurdle in miniaturization of current electronic devices. Herein, a scalable solution‐based layer‐by‐layer engineering of metallic and high‐κ dielectric nanosheets into multilayer nanosheet capacitors (MNCs) with overall thickness of ≈20 nm is presented. The MNCs are built through neat tiling of 2D metallic Ru0.95O20.2? and high‐κ dielectric Ca2NaNb4O13? nanosheets via the Langmuir–Blodgett (LB) approach at room temperature which is verified by cross‐sectional high‐resolution transmission electron microscopy (HRTEM). The resultant MNCs demonstrate a high capacitance of 40–52 µF cm?2 and low leakage currents down to 10?5–10?6 A cm?2. Such MNCs also possess complimentary in situ robust dielectric properties under high‐temperature measurements up to 250 °C. Based on capacitance normalized by the thickness, the developed MNC outperforms state‐of‐the‐art multilayer ceramic capacitors (MLCC, ≈22 µF cm?2/5 × 104 nm) present in the market. The strategy is effective due to the advantages of facile, economical, and ambient temperature solution assembly.  相似文献   
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