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101.
In the present study, an electrochemical sensor has been designed for the direct measurement of silicon content in hot metal. The sensor represents a galvanic silicon concentration cell of the type Nisat—Si(1) II silicate electrolyte (1) II Fe—C—Si(1) The tubular silica-glass sensor can be immediately immersed into the metal bath at a response time of 30 to 60 s. A reproducible EMF vs. wt.% Si relationship was obtained for measurements in carbon-saturated Fe—C—Si melts at 1400°C and Si contents from 0.05 to 1.8 wt.%. This relationship is nearly identical with the cell function calculated from thermodynamic data. 相似文献
102.
Three-dimensionally ordered macroporous (3DOM) polyimide matrix with different pore size (1.3 μm–200 nm) was fabricated, and its structural effect on some properties of composite membrane was investigated. The composite membrane prepared by impregnation of 2-acrylamido-2-methylpropanesulfonic acid polymer (PAMPS) exhibited swelling ratios as low as 2–3% in water or methanol solutions, compared with about 400% of PAMPS itself. The swelling ratio of composite membrane was constant regardless of the 3DOM pore size. However, methanol permeability strongly depended on the pore size. In particular, it was drastically reduced when connecting windows among macropores became less than 100 nm. On the other hand, proton conductivity changed with 3DOM matrix porosity according to Archie's law. The porosity of 3DOM matrix is basically constant even if the pore size changes. Therefore, we suppressed the methanol crossover without lowering of proton conductivity due to reducing the matrix pore size, and the selectivity (proton conductivity/methanol permeability) of 1.2 × 105 S cm−3 s, which was one order of magnitude greater than that of Nafion®, was achieved. 相似文献
103.
Single line defect optical waveguides in a photonic crystal airbridge fabricated into a silicon-on-insulator wafer with a minimum propagation loss of 11 dB/mm are demonstrated. The observed propagation loss spectrum and near field patterns at fibre communication wavelengths agree well with those expected from the photonic band calculation 相似文献
104.
Suitable catalysts for the decomposition of methane into carbon and hydrogen and for the regeneration of methane by hydrogenation of the carbon have been looked for in a series of transition metals and precious metals supported on various carriers. The most active catalyst for both reactions was Ni/SiO2. The carbon formed on this catalyst was thermodynamically less stable than graphite. The different rate equations for the decomposition of methane obtained for the fresh and carbon deposited Ni/SiO2 suggest that the rate-determining steps are different for the two catalysts. The highest number of carbon atoms deposited per one Ni atom was 31 at 773 K. However, the number of methane molecules recovered easily at 773 K was limited to 1.5 per Ni atom.
A physical mixture of Ni/SiO2 and CaNi5, a hydrogen-absorbing alloy, enhanced the decomposition rate of methane, enabling the complete conversion of methane at 773 K beyond the thermodynamic limitation. The presence of CaNi5 at 273 K separated from the catalyst in a reaction system further enhanced the decomposition of methane due to an increased hydrogen-absorbing capacity of the CaNi5 at low temperatures. The carbon deposited on Ni/SiO2 in this case was reactive to be hydrogenated back to methane at 773 K, giving an average 7.5 CH4 molecules per one Ni atom. 相似文献
105.
Soichiro Nakamura Yasuhiro Suzuki Eri Ishikawa Toshiharu Yakushi Hao Jing Takahide Miyamoto Kiyoshi Hashizume 《Food chemistry》2008
A major allergenic protein of buckwheat, Fag e 1 prepared from common buckwheat (Fagopyrum esculentum), was covalently linked with food-grade polysaccharides, arabinogalactan or xyloglucan through the controlled dry-heating at 60 °C under 65% relative humidity. The introduction of polysaccharide chain onto the molecular surface of Fag e 1 reduced the allergenicity of Fag e 1. The results revealed that the Maillard-type glycosylation of Fag e 1 with polysaccharides brought about a drastic reduction of the reactivity against human sera of buckwheat-allergy subjects, using immuno dot-blotting, QCM analysis and ELISA. In addition, the glycosylation of Fag e 1 yielded a great improvement of its surface functionality. Solubility of Fag e 1 at the neutral pH was substantially increased up to 13.5 times and 9.6 times by the conjugation with arabinogalactan and xyloglucan, respectively. Emulsifying properties of Fag e 1 were also improved by the glycosylation, of which both emulsifying activity and emulsion stability were more than 6 times higher than those of the native protein. 相似文献
106.
Seongyop Lim Seong-hwa Hong D. Duayne Whitehurst Isao Mochida Kiyoshi Yokogawa 《Carbon》2007,45(1):173-179
An easy templateless method to synthesize porous carbon nanofibers (CNFs) having radially-oriented mesopores is reported, using selective gasification with nano-sized catalyst particles and hydrogen as the gasification reagent. The gasification generated pores whose size corresponds to that of the catalyst particle used for the drilling. The pores were formed along the graphitic layers, reflecting the structural alignment in the CNFs. The pore size and structure can be controlled by selection of catalyst and gasification conditions. 相似文献
107.
Hiroshi Kihira Takehide Senuma Kiyoshi Nishioka Yutaka Sakata 《Corrosion Science》2005,47(10):2377-2390
Japanese Specification for Highway Bridges [Japan Road Association: Specification for Highway Bridges—I & II, 2002.3] has been revised in 2002, which clearly states that degradation of bridge members, including those of weathering steels, to occur in prolonged period of time must be taken into account at the design stage to realize long term structural durability. To cope with the revised paradigm, SABI chemistry committee in Japan Society of Corrosion Engineers has proposed durable state concept [SABI Chemistry Committee of Japan Society of Corrosion Engineers, in: Proc. 132nd Symposium for Corrosion and Protection, 2001.6.25, p. 3], which is defined as a condition in which corrosion rate of steel is slow enough not to form thick rust [H. Kihira, K. Shiotani, H. Miyuki, T. Nakayama, M. Takemura, Y. Watanabe, Doboku Gakkai Ronbun-shu (J. Japan Soc. Civil Engineers) No. 745/I-65, 2003.10, pp.77-87]. Since corrosiveness of atmosphere differs by location, a corrosion prediction method for both conventional and advanced weathering steels [H. Kihira, A. Usami, K. Tanabe, M. Ito, G. Shigesato, Y. Tomita, T. Kusunoki, T. Tsuzuki, S. Ito, T. Murata, in: Electrochemical Society Proceedings, vol. 99-26, 2000, pp. 127-136] is needed to ensure structural durability for future. Thus, versatile computational scheme for it has been derived through mathematical modeling based upon the durable state concept. 相似文献
108.
Masuhiro Fukaya Toru Miyazaki Pi Zhi Zhao Takao Kozakai 《Journal of Materials Science》1990,25(1):522-528
The free energy of the Fe-base ternary ordering alloys whereB2 andD03 ordered structures are formed is evaluated. The statistical theory is employed using a pairwise interaction approximation taking into account not only the atomic interaction but also the magnetic interaction, based upon the Bragg-Williams-Gorsky model. The application of this model on Fe-Si-Co ordering alloys are demonstrated. The propriety of the calculation results are performed by comparing the experimental results. The influences of the magnetic energy to the stability of ordered structures are also demonstrated. 相似文献
109.
A fuel cell system using yttria-stabilized zirconia as a solid electrolyte was applied to the oxidative coupling of methane. The most active and selective catalyst was BaCO3 deposited on Au-electrode (anode). Optimum conditions for the reaction were examined. The pressure of methane at the anode and that of oxygen at the cathode should be high as much as possible. The optimum temperature was 1073 K. Several advantages of the method are described. 相似文献
110.
采用无偏振片反射式LCD及超低功耗驱动技术制造移动显示器件 总被引:1,自引:1,他引:0
Kiyoshi Minoura Yasushi Asaoka Eiji Satoh Takashi Satoh Ichiro Ihara Sayuri Fujiwara Akio Miyata Yasuhisa Itoh Seijiro Gyoten Noboru Matsuda Yasushi Kubota 代永平 《现代显示》2010,(7):5-9,35
我们通过对材料和制备条件的精细化处理,生产出一种在低刷新频率下无闪烁和图像迟滞现象的反射式显示器。该显示器的功耗非常低,且可在宽温度范围内工作,是未来移动显示器件的潜力平台。 相似文献