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141.
A three-dimensional (3D) digital holographic display system with image processing is presented. By use of phase-shifting digital holography, we obtain the complex amplitude of a 3D object at a recording plane. Image processing techniques are introduced to improve the quality of the reconstructed 3D object or manipulate 3D objects for elimination and addition of information by modifying the complex amplitude. The results show that the information processing is effective in such manipulations of 3D objects. We also show a fast recording system of 3D objects based on phase-shifting digital holography for display with image processing. The acquisition of 3D object information at 500 Hz is demonstrated experimentally. 相似文献
142.
Electrospray pyrolysis, i.e. combination of electrospray and in-flight thermal treatment, has attracted much attention as a preparation method of functional ceramic particles. In this paper, we report the processing detail of spherical TiO2 nano- and microparticles by the electrospray pyrolysis method as well as their photocatalytic activity for hydrogen evolution. Titanium(IV) bis(ammonium lactato)dihydroxide aqueous solutions (TALH aq., 0.2–20 wt%) were injected into a capillary nozzle by a syringe pump (0.15–0.59 mL/min), and were electrosprayed by using DC 4 kV voltage, followed by the pyrolysis at 300–500 °C. Spherical TiO2 nano- and microparticles were successfully obtained. Effects of precursor-liquid concentration, liquid flow-rate, and pyrolysis temperature on the particle size, microstructure and functions were discussed. 相似文献
143.
Connection of Vortices Between Spatially Different Phases in Two-Component Bose-Einstein Condensates
Kenichi Kasamatsu Hiromitsu Takeuchi Muneto Nitta Makoto Tsubota 《Journal of Low Temperature Physics》2010,158(1-2):99-104
We study interfacial topological defects called boojums, a vortex ending or a connecting point of two kinds of vortex cores, in rotating two-component Bose-Einstein condensates. First, we show that the boojum exists at a vortex ending that connects to the interface of the strongly phase-separated condensates. Next, we study various boojums appearing between two phases characterized by different vortex structures, where the intercomponent s-wave scattering lengths are spatially varied. Using three-dimensional simulations of the Gross-Pitaevskii equations, we reveal the detailed structure of the boojums by visualizing its density distribution and effective superflow vorticity. 相似文献
144.
Mitsuharu Tabuchi Yoko Nabeshima Kuniaki Tatsumi Yoshiaki Nitta 《Journal of power sources》2010,195(3):834-844
Fe-substituted Li2MnO3 including a monoclinic layered rock-salt structure (C2/m), (Li1+x(FeyMn1−y)1−xO2, 0 < x < 1/3, 0.1 ≤ y ≤ 0.5) was prepared by coprecipitation-hydrothermal-calcination method. The sample was assigned as two-phase composite structure consisting of the cubic rock-salt () and monoclinic ones at high Fe content above 30% (y ≥ 0.3), while the sample was assigned as a monoclinic phase (C2/m) at low Fe content less than 20%. In the monoclinic Li2MnO3-type structure, the Fe ion tends to substitute a Li (2b) site, which corresponds to a center position of Mn4+ hexagonal network in Mn-Li layer. The electrochemical properties including discharge characteristics under high current density (<3600 mA g−1 at 30 °C) and low temperature (<−20 °C at 40 mA g−1) were severely affected by chemical composition (Fe content and Li/(Fe + Mn) ratio), crystal structure (monoclinic phase content) and powder property (specific surface area). Under the optimized Fe content (0.2 < y < 0.4), the Li/sample cells showed high initial discharge capacity (240-300 mAh g−1) and energy density (700-950 mWh g−1) between 1.5 and 4.8 V under moderate current density, 40 mA g−1 at 30 °C. Results suggest that Fe-substituted Li2MnO3 would be a non-excludable 3 V positive electrode material. 相似文献
145.
Takahiro Kozawa Hideya Hattori Shuhei Ogo Yusuke Ide Yoshikazu Suzuki 《Journal of Materials Science》2013,48(22):7969-7973
A simple and mild synthetic route via a hydrothermal treatment of Mg2TiO4 has been developed to prepare brookite-type TiO2. The hydrothermal conversion of Mg2TiO4 to brookite proceeded in 1 M HCl solution even at 100 °C. The converted brookite grains were composed of the angular particles covered on the textured surface, leaving the original morphology of Mg2TiO4 grains. Compared with the commercially available TiO2 catalysts (rutile, anatase, and P25), the brookite obtained in this study showed a good photocatalytic activity toward the oxidation of benzyl alcohol to benzaldehyde under a simulated sunlight irradiation. 相似文献
146.
147.
Akira Kariyasaki Yoshikazu Yamasaki Masazumi Kagawa Tohru Nagashima Akiharu Ousaka Shigeharu Morooka 《传热工程》2013,34(1-2):28-36
A technique was developed and tested to measure the local thickness of a droplet or a liquid film on a surface of an opaque or thick single transparent plate by an interference fringe pattern that was easily formed by reflecting laser lights. Monochromatic epi-illumination through an objective lens of a conventional microscope was provided by a 5 mW or 300 mW laser and a filter to remove the noise caused by laser speckle. The incremental height difference of the liquid layer between neighboring maxima or minima of fringes was evaluated from the wavelength of the laser light and the refractive index of the liquid. Estimation error of a local inclination angle was discussed using ray tracing under parallel illumination approximation. Droplet profiles evaluated from the interferogram that were obtained by the present fringe method agreed well with those by Laser Focus Displacement Meter. Measurement was made to ensure the usefulness of the present technique. It was made clear that the contact angle of a liquid droplet could be obtained precisely and swiftly, even in small size or small contact angle, and that instantaneous three-dimensional profile of a liquid film on a bubble moving in a microchannel could be measured. The fringe method had sufficient potential to obtain more detailed information about three-dimensional characteristics of liquid film in flows such as the generation, breakdown, and growth of waves and the liquid film on a bubble at the beginning of movement. 相似文献
148.
149.
Yuki Nitta Keishi Okamoto Tatsuyuki Nakatani Hideo Hoshi Akihiko Homma Eisuke Tatsumi Yoshiyuki Taenaka 《Diamond and Related Materials》2008,17(11):1972-1976
With the purpose of applying diamond-like carbon (DLC) thin films as a biocompatible material, we experimented with introducing functional groups such as amino and carboxyl groups to the surface of DLC thin films by plasma surface treatment. From the results, it was found that the contact angle values of the DLC thin films surface were decreased with increasing in the OCO bonded network on the surface. Measurement of the zeta potential when the amounts of the functional groups were varied showed that this successfully varied the zeta potential over the wide range of − 48 mV to + 12 mV. It was found that when carboxyl groups are introduced by O2 plasma modification of the DLC thin films surface, the zeta potential was lower than that of untreated DLC thin films sample. It was also found that amino groups can be introduced to the DLC thin films surface by NH3 plasma treatment, the zeta potential was higher than that of untreated DLC thin films sample. This means that zeta potential of the DLC thin films can also be controlled by controlling these two functional groups. Therefore, we have succeeded in developing a multifunctional DLC thin films that does not use polymers and is suitable as a biocompatible material. 相似文献
150.
An optical system for authentication using a 3D (3D) random phase object with various wavelength readouts is proposed. The 3D phase object without surface modulation is secure when the scattering is strong enough because it prevents from the interferometric measurement. The identification is implemented by the correlation between a measured speckle pattern of the 3D phase object and stored speckle patterns. For accurate identification, two speckle patterns of the 3D object obtained by illuminating two wavelengths are used. Experimental demonstrations and numerical evaluations of wavelength selectivity are presented. 相似文献