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1.
This paper proposes a method for the coordinated control of power factor by means of a multiagent approach. The proposed multiagent system consists of two types of agent: single feeder agent (F_AG) and bus agent (B_AG). In the proposed system, an F_AG plays as an important role, which decides the power factors of all distributed generators by executing the load flow calculations repeatedly. The voltage control strategies are implemented as the class definition of Java into the system. In order to verify the performance of the proposed method, it has been applied to a typical distribution model system. The simulation results show that the system is able to control very violent fluctuation of the demands and the photovoltaic (PV) generations. 相似文献
2.
Photocatalysts have attracted great research interest owing to their excellent properties and potential for simultaneously addressing challenges related to energy needs and environmental pollution. Photocatalytic particles need to be in contact with their respective media to exhibit efficient photocatalytic performances. However, it is difficult to separate nanometer-sized photocatalytic materials from reaction media later, which may lead to secondary pollution and a poor recycling performance. Hydrogel photocatalysts with a three-dimensional (3D) network structures are promising support materials for photocatalysts based on features such as high specific surface areas and adsorption capacities and good environmental compatibility. In this review, hydrogel photocatalysts are classified into two different categories depending on their elemental composition and recent progresses in the methods for preparing hydrogel photocatalysts are summarized. Moreover, current applications of hydrogel photocatalysts in energy conversion and environmental remediation are reviewed. Furthermore, a comprehensive outlook and highlight future challenges in the development of hydrogel photocatalysts are presented. 相似文献
3.
HIRAMITSU SUZUKI SHUN WADA SEIICHI HAYAKAWA SINPATIRO TAMURA 《Journal of food science》1985,50(2):358-360
To prevent loss of w3 polyunsaturated fatty acids over long-term preservation, the effects of temperature and oxygen absorber on the fatty acids of sardine oil stored in air-tight film were studied. The fatty acids of sardine oil and lipids in the diet of experimental animals rapidly decreased over 1 month at 22°C. The amounts in the diet decreased slowly at 2°C; however, no alterations in the oil samples were observed for 6 months. Also, the amounts did not change at -30°C. Significant changes in samples treated with oxygen absorber were not observed under all temperatures during 6 months storage (P > 0.05). These results indicate that treatment with an oxygen absorber and/or freezing can prevent ω3 polyunsaturated fatty acids of fish oil from decreasing during storage. 相似文献
4.
氧浓度对近临界水中纤维素分解的影响 总被引:3,自引:0,他引:3
研究了不同初始氧浓度对纤维素在近临界水中分解的影响,实验结果表明,氧浓度显著地影响产物总碳收支平衡,液相不同组分的收率、气体的产量以及气相产物的组成,微量氧对产物总碳收支平衡影响不大,而对液相不同组分的收率有一定的影响。从实验结果可以看出,离子型反应机理在纤维素水解的第一步中起主导作用。而单糖的进一步分解是一个以自由基反应机理为主的过程。 相似文献
5.
TAKESHI KIKUCHT 《Journal of the American Ceramic Society》1977,60(3-4):148-150
The subsolidus phase equilibria in the system Bi2 O3 -TiO2 -Nb2 O5 at 1100°C were determined by solid-state reaction techniques and X-ray powder diffraction methods. The system was found to contain 4 ternary compounds, i.e. Bi3 TiNbO9 , Bi7 Ti4 NbO21 , a cubic pyrochlore solid solution having a compositional range of 3Bi2 O3 · x TiO2 (7– x )Nb2 O5 where x ranges from 2.3 to 6.75, and an unidentified phase, 4Bi2 O3 ·11TiO2 ·5Nb2 O5 . 相似文献
6.
综合介绍了脉冲电流通过细金属丝放电(pulsed wire discharge,PWD)制备纳米粉体的方法.讨论了影响纳米粉体,特别是晶粒尺寸的因素,以防止形成亚微米颗粒.因为达到电压峰值的丝的沉积能相当于丝的汽化能,因此,能夠计算出沉积能.随着所施加的能量增加,气体压力降低,介质气体的热扩散率增大,晶粒尺寸变小.在惰性气氛中,采用PWD工艺,由金属蒸气急冷可制备金属粉体.如果介质气体变为氧气或者氨气,就能制备氧化物、氮化物纳米粒子.要制备双金属合金、双氧化物或氮化物纳米粒子就必需采用双金属丝和不同的介质气体.采用PWD工艺,在有机气体或烟气中,能制备电磁屏蔽和导电浆料和其它用途的钝化纳米粒子.采用丝输送器而实现大量生产纳米粉体的PWD工艺一个实例证明了PWD工艺生产纳米粉体的可行性. 相似文献
7.
Basic Study on Islanding Detection Method for PV Systems by Harmonic Impedance Detection in Case of Including Induction Motor in Load System 下载免费PDF全文
YOSHIAKI YOSHIDA HIROKAZU SUZUKI KOJI FUJIWARA YOSHIYUKI ISHIHARA 《Electrical Engineering in Japan》2016,194(3):20-34
It is important that photovoltaic (PV) systems detect islanding caused by power system faults to ensure electrical safety. Thus we propose a novel islanding detection method which detects the harmonic impedance by injecting harmonic currents synchronized with the exciting current harmonics of the pole transformer. For the case in which an induction motor load is included in the load system, basic experiments on islanding detection and simulation analysis are conducted to verify the effectiveness of the proposed method. 相似文献
8.
YOSHIKI SUZUKI MINORU MIZUTANI TAKAMITSU SUGIURA NAOKI SAKAI TAKASHI OHIRA 《Electrical Engineering in Japan》2016,195(1):63-71
Electric vehicles (EVs) are expected to play a leading role in the changeover from fossil fuels to clean energy. However, EVs are currently not very popular, owing to their short cruising distance and long charging time. Wireless power transfer from the infrastructure to running EVs is expected to be the solution to these problems. Electric vehicle and electrified roadway (EVER) has been proposed as a wireless power transfer system for EVs while in motion. Via‐wheel power transfer (V‐WPT) is expected to be a wireless power transfer scheme for EVER. We designed and prototyped a 1:32 scale model of a V‐WPT system that consists of an RF inverter, an electrified roadway, a rectifier, and an EV with a dc motor. The output power of the prototype RF inverter was 5.9 W and the dc–RF conversion efficiency was 36.6%. The LC matching circuits for the V‐WPT were designed with two‐port conjugate matching because S11 of the V‐WPT was intrinsically –0.06 dB. After matching, the S11 value was reduced to –21.5 dB. The power transmission efficiency of the V‐WPT system was 75%. The RF–dc conversion efficiency of the rectifier was 62%. The total efficiency of the EVER system was 24.2%. 相似文献
9.
The preparation for an experimental soft x-ray tomography study on the Heliotron J (H-J) machine is carried out, with the objectives of evaluating the capability of the current soft x-ray tomographic system in terms of the identification of different mode structures and their poloidal rotation, and the axis shift with different plasma and machine parameters, and fixing the physics goals for the experimental study. These preparations were carried out via a simulated soft x-ray data set arising from different plasma conditions, such as magnetic islands, low beta and high beta. Soft x-ray tomography (SXT) is performed by the discrete pixel method including singular value decomposition and Phillips–Tikhonov regularization, to obtain clear and smooth images. The H-J soft x-ray tomography results from simulated soft x-rays for the equilibrium H-J plasma sensed the magnetic axis shift clearly and an estimate was also achieved. Successful reconstruction for mode structure m=1/n=1 was obtained along with the realization of the poloidal rotation of the structure. The reconstruction for the m=2/n=1 mode was not very clear for the current soft x-ray diagnostic design. Effective mode identification was not possible due to the lack of measurements. The SXT from the current soft x-ray diagnostic on H-J, the magnetic axis shift can be estimated and the m=1/n=1 mode can be studied. Study of higher poloidal modes is difficult with the current design. 相似文献
10.
TAKESHI TAKAMORI HIROKICHI SEO MINORU TASHIRO 《Journal of the American Ceramic Society》1969,52(11):582-585
Titanium-containing glasses were prepared by fusion of a base glass (BaO·B2 O3 SiO2 ) and TiO2 and/or Ti2 O3 in Ar. Their resistivities did not vary with melting time and temperature. Interaction of Ti4+ and Ti3+ in the glasses was deduced by spectroscopy, but the valence states in the batch compositions were preserved in the glasses, according to the chemical analysis. Glasses containing either Ti4+ or Ti3+ had very high resistivities, whereas the glass prepared by melting a mixture of a Ti4+ -containing and a Ti3+ -containing glass had much lower resistivity. All results confirmed the possibility of controlling the resistivity by batch composition for these glasses. 相似文献