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81.
Fujita K Miyamura T Sano M Kato I Takegawa K 《Journal of Bioscience and Bioengineering》2002,93(6):614-617
Endo-beta-N-acetylglucosaminidase from Arthrobacter protophormiae (Endo-A) has transglycosylation activity, and high-mannose-type oligosaccharides are transferred to suitable glycosides as acceptor substrates. The acceptor specificity of Endo-A-catalyzed transglycosylation toward various disaccharides was investigated. To identify an effective acceptor for the transglycosylation by Endo-A, the reaction was carried out using various disaccharides. Endo-A transferred high-mannose-type oligosaccharides more efficiently to beta-linked disaccharides (cellobiose, gentiobiose, sophorose, and laminaribiose) than to alpha-linked disaccharides (isomaltose, maltose, nigerose, kojibiose, and trehalose) as acceptor substrates. The transglycosylation products, (Man)6GlcNAc-Glc-beta-Glc, were more rapidly hydrolyzed than (Man)6GlcNAc-Glc-alpha-Glc. These results indicate that Endo-A recognizes the anomeric configuration of the acceptor substrates, and beta-linked glycosides are suitable for the synthesis of transglycosylation products. 相似文献
82.
83.
Atsushi Sano Masato Kurihara Kazuya Ogawa Tsuyoshi Iijima Satoshi Maruyama 《Journal of power sources》2009,192(2):703-707
The effect of alkali function group contained in electrode binder was investigated. Carboxy methyl cellulose (CMC) improved the initial irreversible capacity loss in graphite negative electrode. Lithium acetate also improved the initial cycle efficiency. On the other hand, ethyl cellulose (EC) and hydroxyl propyl methyl cellulose (HPMC), which do not have a carboxylic group, did not decrease the reductive electrolyte decomposition. After charge and discharge cycle, the surface film composition on the electrode with CMC was less than on the electrode without CMC. This suggests that a carboxylic group in the binder acted as a catalyst and promoted the solid electrolyte interphase (SEI) formation which prevents the excess electrolyte decomposition on the graphite electrode. 相似文献
84.
Yuta Nabatame Tsuyoshi Matsumoto Yuki Ichige Takashi Komine Ryuji Sugita Masayuki Murata Yasuhiro Hasegawa 《Journal of Electronic Materials》2013,42(7):2172-2177
In this study, we have numerically analyzed the transport properties of Bi-Sb nanowires, taking into account wire boundary scattering. Wire boundary scattering slightly decreased the Seebeck coefficient of Bi-Sb nanowires. This effect is due to the observation that boundary scattering and the mobility ratio of L-point electrons to T-point holes in the nanowires are smaller than those in bulk Bi-Sb because the wire boundary scattering suppresses the mobilities of L-point electrons and heavy holes. The largest Seebeck coefficient for all wire diameters was obtained when the Sb concentration was 5 at.%. The effective mass approached zero near 5 at.% Sb, and the small effective mass led to a large subband shift in each band. Thus, a small effective mass enhances the quantum effect at a fixed wire diameter, even if wire boundary scattering is taken into account. 相似文献
85.
86.
In this study, hydrothermal upgrading and dewatering of raw tropical peat derived from Pontianak, West Kalimantan-Indonesia was evaluated at temperatures ranging from 150 to 380 °C, a maximum final pressure of 25.1 MPa and a residence time of 30 min. The moisture content of the raw peat was approximately 90 wt.%. Raw peat was hydrothermally upgraded without the addition of water in the laboratory scale. The yield of the solid products was between 53.0 and 99.7 wt.% and the effective calorific value of hydrothermally dewatered peat was between 17,290 and 29,209 kJ/kg following hydrothermal upgrading. In addition, the oxygen content in the solid product was varied from 38.4 to 15.6 wt.% after upgrading, while the carbon content from 55.2 to 77.8 wt.%. The hydrothermally upgraded peat fuel product also had an equilibrium moisture content of 2.3 wt.% and a maximum equilibrium moisture content of 17.6 wt.%. Upgraded peat is characteristically resistant to moisture adsorption at high humidity, which makes it promising for fuel based combustion. The change in the carbon-functional groups and their properties, as determined by FTIR and 13C NMR, are discussed in terms of the hydrothermal upgrading and dewatering process. 相似文献
87.
88.
Sausan Al-Riyami Shinya Ohmagari Tsuyoshi Yoshitake 《Diamond and Related Materials》2010,19(5-6):510-513
Nitrogen-doped ultrananocrystalline diamond (UNCD)/hydrogenated amorphous carbon (a-C:H) films were deposited by pulsed laser deposition (PLD). Nitrogen contents in the films were controlled by varying a ratio in the inflow amount between nitrogen and hydrogen gases. The film doped with a nitrogen content of 7.9 at.% possessed n-type conduction with an electrical conductivity of 18 Ω? 1 cm? 1 at 300 K. X-ray photoemission spectra, which were measured using synchrotron radiation, were decomposed into four component spectra due to sp2, sp3 hybridized carbons, C=N and C–N. A full-width at half-maximum of the sp3 peak was 0.91 eV. This small value is specific to UNCD/a-C:H films. The sp2/(sp3 + sp2) value was enhanced from 32 to 40% with an increase in the nitrogen content from 0 to 7.9 at.%. This increment probably originates from the nitrogen incorporation into an a-C:H matrix and grain boundaries of UNCD crystallites. Since an electrical conductivity of a-C:H does not dramatically enhance for this doping amount according to previous reports, we believe that the electrical conductivity enhancement is predominantly due to the nitrogen incorporation into grain boundaries. 相似文献
89.
90.
Tsuyoshi Nishiwaki Atsushi Yokoyama Zen-ichiro Maekawa Hiroyuki Hamada 《Composite Structures》1995,32(1-4):635-640
Localized impact problems for composite structures have recently become important. In this study, some elastic wave velocities in 7-ply GFRP laminate with [02/903/02] ply orientation after low speed impact was investigated by using both experimental methods and finite element methods. For the finite element simulation, the quasi-three-dimensional model was used. Comparing the results, the validity for the application of this model to the dynamic problem was estimated. Moreover the quasi-three-dimensional model is applied to the GFRP plates with interlaminar delamination. The relationship between the elastic wave velocities and delaminated states is discussed. 相似文献