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91.
Effect of treatment of activated carbon fiber cloth electrodes with cold plasma upon performance of electric double-layer capacitors 总被引:4,自引:0,他引:4
Masashi Ishikawa Atsushi Sakamoto Masayuki Monta Yoshiharu Matsuda Koichi Ishida 《Journal of power sources》1996,60(2):233-238
Charge/discharge behavior of electric double-layer capacitors composed of activated carbon fiber cloth (ACFC) electrodes and an organic electrolyte was investigated. The modification of the ACFC electrodes was performed using cold plasma generated in argon-oxygen atmosphere. The effect of the cold plasma treatment of the ACPC electrodes on the capacitor performance was discussed on the basis of the physical and chemical properties of the ACFC surface such as pore radius distribution and surface atom concentration. 相似文献
92.
Carbon Nanotubes: Simple Salt‐Coordinated n‐Type Nanocarbon Materials Stable in Air (Adv. Funct. Mater. 18/2016) 下载免费PDF全文
93.
Shoichi MATSUDA Naomichi SAJI Minoru YAGA Masaaki ISHIKAWA Kenyu OYAKAWA 《热科学学报(英文版)》2010,19(3):228-233
This paper will present the characteristics of flow behavior and thermal field of both free and
impingement jet issued from a circular orifice nozzle at Re=8900.The flow behavior of a single round
jet and impingement jet was observed by smoke flow visualization recorded by a high speed camera
using 5000 frame per second.Heat transfer coefficient on the impingement surface was measured by
means of infrared camera (TVS-8500,Avio) with a two-dimensional array of Indeum-Antimony (In Sb)
sensors varying in the separation distance between the nozzle and the target plate.The heat transfer
coefficient changes in time and spatial.Therefore,the root mean square distribution of the heat
transfer was obtained from the data.As a result,it was confirmed that the longitudinal vortex was
observed outside of the ring vortex,and then the longitudinal vortex was penetrated in the jet
flow.Moreover,the high value of root mean square of the heat transfer coefficient has spread radially
in stripy manner,which is caused as the results of the longitudinal vortexes flowing in the radial
direction on the impingement plate. 相似文献
impingement jet issued from a circular orifice nozzle at Re=8900.The flow behavior of a single round
jet and impingement jet was observed by smoke flow visualization recorded by a high speed camera
using 5000 frame per second.Heat transfer coefficient on the impingement surface was measured by
means of infrared camera (TVS-8500,Avio) with a two-dimensional array of Indeum-Antimony (In Sb)
sensors varying in the separation distance between the nozzle and the target plate.The heat transfer
coefficient changes in time and spatial.Therefore,the root mean square distribution of the heat
transfer was obtained from the data.As a result,it was confirmed that the longitudinal vortex was
observed outside of the ring vortex,and then the longitudinal vortex was penetrated in the jet
flow.Moreover,the high value of root mean square of the heat transfer coefficient has spread radially
in stripy manner,which is caused as the results of the longitudinal vortexes flowing in the radial
direction on the impingement plate. 相似文献
94.
Hiroki Ishikawa Ryoko Komaki Haruo Naitoh Akira Yamaba Hiroki Katoh 《Electrical Engineering in Japan》2010,173(1):51-59
This paper presents a current control design for switched reluctance motors (SRMs). The electric transfer characteristic of the motors is studied first. Their transfer function is shown to be expressible by a pure resistive component, which is not constant but varies depending on the motor current and speed. The current control design for SRMs follows the classical design technique used for DC machines, where the zeros of the PI controller cancel the poles of Ls+R. Because the transfer function of SRMs does not have any poles, an I controller is suitable for them. The integral gain should be adjusted in order to compensate the nonlinearity, that is, the variation in the equivalent resistor of the SRMs' transfer function. The values of the integral gain are tuned and tabulated for the motor speed and current. Simulation and experiment demonstrate that the current and speed of the SRMs present good responses without dependence on the motor speed and current. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 173(1): 51–59, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20987 相似文献
95.
Naoki Izawa Tomoko Hanamizu Toshiro Sone Katsuyoshi Chiba 《Journal of Bioscience and Bioengineering》2010,109(4):356-360
To increase the hyaluronic acid (HA) yield from Streptococcus thermophilus YIT 2084, fermentation conditions (pH, temperature, agitation, aeration) were optimized in milk-based medium, and the effects of supplemental soybean peptides, which have different molecular weight distributions, were determined. HA production was enhanced to approximately 100 mg/l at pH 6.8 and 33–40 °C. Agitation speed and aeration rate slightly affected HA production. Soybean peptides including those of high molecular weight (approximately 27 to 130 kDa) further increased HA production to 208 mg/l under the optimal condition (pH 6.8, 35 °C, 100 rpm), which was 20-fold greater than non-optimal condition. HA production was no longer related to the specific growth rate. The HA produced under the optimal condition included a large amount of high-molecular-weight fraction of 100 to 2000 kDa, compared with under the basal condition without optimization. 相似文献
96.
Masatoshi Hasegawa Mari Fujii Junichi Ishii Shinya Yamaguchi Eiichiro Takezawa Takashi Kagayama Atsushi Ishikawa 《Polymer》2014
A novel cycloaliphatic monomer for polyimides (PI), 1S,2S,4R,5R-cyclohexanetetracarboxylic dianhydride (H′-PMDA) is proposed in this work. H′-PMDA shows high polymerizability with various diamines in contrast to its isomer, i.e., conventional hydrogenated pyromellitic dianhydride (H-PMDA) and leads to highly flexible and colorless PI films with very high Tg's. In particular, the combinations with rigid structures of diamines give rise to PIs with significantly decreased coefficients of thermal expansion (CTE) owing to high extents of in-plane chain orientation induced by thermal imidization, whereas the H-PMDA-based counterparts do not. The decreased CTE reflects structural rigidity/linearity of the H′-PMDA-based diimide units as supported by liquid crystallinity observed in the corresponding model compound. Solution casting of a chemically imidized PI derived from H′-PMDA and 2,2′-bis(trifluoromethyl)benzidine (TFMB) results in a lower CTE than that of the thermally imidized counterpart, suggesting the presence of a self-orientation phenomenon during solvent evaporation. The mechanism is proposed in this work. H′-PMDA/TFMB and its copolymer systems can be useful as plastic substrates in image display devices and/or novel coating-type optical compensation films. 相似文献
97.
Hiromasa Ishikawa 《热应力杂志》2013,36(2):211-222
Abstract This paper presents a theoretical study of the stresses in an infinite circular solid cylinder subjected to rapid surface heating and cooling. A quasistatic, uncoupled, thermoelastoplastic analysis based on the incremental theory of plasticity is formulated, and a numerical procedure is developed for a method of successive elastic solutions. The material of the cylinder is assumed to have temperature-dependent properties and to be characterized by the Romberg-Osgood stress-strain relation. The transient and residual stress distributions are discussed in detail, along with variations of the equivalent stress and plastic strain with time. 相似文献
98.
99.
Role of zinc compounds on the formation, morphology, and adsorption characteristics of β-FeOOH rusts
To simulate the corrosion of galvanized steel in marine zone, β-FeOOH was prepared by aging the FeCl3 solutions containing ZnCl2 and zinc rusts such as ZnO and zinc hydroxychloride (Zn5(OH)8Cl2·H2O:ZHC). Adding ZnCl2, ZnO, and ZHC inhibited the crystallization and particle growth of β-FeOOH and the inhibitory effect was in order of ZHC ≈ ZnO > ZnCl2. The adsorption of H2O and CO2 was suppressed by adding ZnCl2, ZnO, and ZHC. These results imply that the rust formed on galvanized steel in marine environment is more compact, amorphous, and hydrophobic in nature which may lead to improve the corrosion resistance. 相似文献
100.
We applied a Mo/B4C multilayer coating to a laminar holographic grating with 2400 grooves/mm and a 1-m radius of curvature. By use of synchrotron soft x rays the multilayer-coated grating was evaluated to have diffraction efficiencies of 3.1% and 0.017% for s- and p-polarized radiation, respectively, at a 6.7-nm wavelength at a 45.35 degrees grazing angle of incidence in the +1 (inside) grating order. Thus the polarizance was estimated to be 98.9% at least. The zero-order peak was suppressed by the destructive interference caused by the groove profile. 相似文献