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81.
High-temperature structural change of catalytic MnOx-LaOx-Al2O3 powder for lean-exhaust NOx removal treatment 总被引:2,自引:0,他引:2
Solid-state reaction between compositions and sintering behavior of powders at 600–1100°C were examined by x-ray diffraction, electron spin resonance and surface area measurement. Manganese-alumina catalyst, which was even subjected to heat treatment at 1000°C in air, had the NO removal conversion efficiency of 22% at 350–400°C Structural change and chemical state of alumina-supported manganese catalytic powders were studied for the purpose of the improvement of performance in automotive lean-burn NOx removal treatment for a model lean exhaust with high space velocity of 100,000 h–1. La-modification of support was effective to maintain high surface area of powder, however it did not lead to the improvement of NO removal activity for manganese-based catalyst. 相似文献
82.
High-rate deposition of hydrogenated amorphous silicon films using inductively coupled silane plasma
Nobuki Sakikawa Yoshinori Shishida Seiichi Miyazaki Masataka Hirose 《Solar Energy Materials & Solar Cells》2001,66(1-4)
Inductively coupled plasma (ICP) generated at 13.56 MHz has been employed for high-rate deposition of device-quality hydrogenated amorphous silicon (a-Si:H). It has been shown that an increase in the flow rate of a monosilane gas enhances the generation rate of deposition precursors, while the ion flux decreases and becomes saturated. The defect density reaches the minimum at a deposition rate of 2.3 nm/s. It has also been demonstrated that even at deposition rates around 4 nm/s, a-Si:H deposited at 150°C exhibits a subgap defect density lower than 6×1016 cm−3 after 12 h AM1 (100 mW/cm2) light soaking. 相似文献
83.
84.
Hitoshi Kanoh Miyuki Matsumoto Kazuyo Hasegawa Nobuko Kato Seiichi Nishihara 《Engineering Applications of Artificial Intelligence》1997,10(6):531-537
Several approximate algorithms have been reported to solve large constraint-satisfaction problems (CSPs) within a practical time. While those papers discuss techniques to escape from local optima, this paper describes a method that actively performs global searches. The present method improves the rate of search of genetic algorithms by using viral infection instead of mutation. Partial solutions of a CSP are considered to be viruses, and a population of viruses is created, as well as a population of candidate solutions. The search for a solution is conducted by crossover and infection. Infection substitutes the gene of a virus for the locus decided by the virus. Experimental results using randomly generated CSPs prove that the proposed method is faster that usual genetic algorithms at finding a solution when the constraint density of a CSP is low. 相似文献
85.
Toshihiko Noguchi Yosuke Takata Yukio Pyamashita Yoshimi Komatsu Seiichi Ibaraki 《Electrical Engineering in Japan》2007,161(3):31-40
This paper describes an ultrahigh‐speed permanent‐magnet synchronous motor drive, which is embedded in a turbocharger of an internal‐combustion engine. The electrical drive makes it possible to enhance output power of the turbocharger in a motoring mode and to retrieve combustion energy from exhaust gas in a regenerating mode. Computer simulations and experimental tests are conducted to examine various operation characteristics of a prototype. The experimental data demonstrate 220,000‐r/min operation at 2.2‐kW inverter output power, in good agreement with the simulation results and proving the feasibility of the proposed system. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(3): 31–40, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20408 相似文献
86.
87.
88.
Recovery of liquid fuel from hydrocarbon-rich microalgae by thermochemical liquefaction 总被引:11,自引:0,他引:11
Yutaka Dote Shigeki Sawayama Seiichi Inoue Tomoaki Minowa Shin-ya Yokoyama 《Fuel》1994,73(12):1855-1857
Liquefaction of Botryococcus braunii, a colony-forming microalga, with high moisture content was performed with or without sodium carbonate as a catalyst for conversion into liquid fuel and recovery of hydrocarbons. A greater amount of oil than the content of hydrocarbons in B. braunii (50 wt% db) was obtained, in a yield of 57–64 wt% at 300 °C. The oil was equivalent in quality to petroleum oil. The recovery of hydrocarbons was a maximum (>95%) at 300 °C. 相似文献
89.
Based on the present state of the art of the separation technology, recycling of fission-product rare elements (FRE) in the FBR spent fuel is discussed. The rad.-waste fractionation is in accordance with the present society's trend toward zero-emission, and the mean of salt-free method utilizing electrochemistry agrees with the principles of the newly established green chemistry. A catalytic electrolytic extraction method is proposed to separate the target, radioactive but potentially strategic elements, Pd, Ru, Rh, Re (Tc), Te and Se dissolved in the HLLW. It avoids secondary waste arising. This method is particularly feasible for the separation of Pd where cyclic reaction of metal cations such as Pd(II) or Fe(II), acting as promoters or mediators and already contained in HLLW, accelerates the electrochemical deposition of Ru, Rh and Re. Elemental separation not only offers alternative material resources to meet expanding demands for catalysts in Fuel Cell/Soft Energy system but is also the first step for transmutation or other selective strategies for waste management of long-lived fission products (LLFP). 相似文献
90.
Okuyama H. Miyajima T. Morinaga Y. Hiei F. Ozawa M. Akimoto K. 《Electronics letters》1992,28(19):1798-1799
The continuous wave operation of an ZnSe/ZnMgSSe laser diode was achieved for the first time at 77 K. Blue stimulated emission was observed at a wavelength of 447 nm and the threshold current density was 225 A/cm/sup 2/.<> 相似文献