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排序方式: 共有911条查询结果,搜索用时 31 毫秒
61.
Uesugi N. Horiguchi T. Nakazawa M. Murakami Y. 《Selected Areas in Communications, IEEE Journal on》1986,4(5):732-736
The optical fiber cable measurement instruments developed by NTF for field use in the 1.3 μm wavelength are discussed. The properties of a stabilized optical light source for single-mode fiber attenuation measurement, optical time-domain reflectometer using a Q-switched Nd:YAG laser as a light source, and chromatic dispersion measurement instrument are described. From the measurement results, these instruments are revealed to be suitable in constructing and maintaining singlemode fiber optical transmission lines. 相似文献
62.
63.
We report research on the development of a method of fabricating three-dimensional microstructures that uses synchrotron radiation light. Some research on three-dimensional processing methods using SR lithography has already been reported. They have involved techniques of applying exposure energy distributions to resist surfaces. Complicated energy distributions need to be applied to resist surfaces to fabricate arbitrary three-dimensional structures. However, we devised a new method that made it possible to fabricate arbitrary three-dimensional microstructures by using a mask with pattern created function. The advantages of this method are that it is suitable for rapid prototyping and it reduces the fabrication time and cost since it is not necessary to fabricate conventional photolithographic masks. Our research involved a basic experiment on this method of fabrication where we succeeded in fabricating a free-form surface by exposing it through an overlapping array of pixels that created a single aperture. Moreover, the pixel size could be made smaller than the aperture size by overlapping adjoining pixels. 相似文献
64.
Date M. Hisaki T. Takada H. Suyama S. Nakazawa K. 《Electron Devices, IEEE Transactions on》2005,52(2):190-193
A method to drastically reduce the power consumption of the backlight in a compact depth-fused three-dimensional display, which consists of a stack of two liquid crystal (LC) panels, is proposed and experimentally validated. To remove the color filters in the LC panels, we introduced the field-sequential technique for color display. The transmittance of the display could be improved by more than one order. Therefore, the luminance of the backlight could be reduced to less than that of a two-dimensional LC display. 相似文献
65.
Sachiro Kakinoki Makoto Kitamura Mitsuhiro Yuge Masakazu Furuta Masahito Oka Yoshiaki Hirano Kenji Kono Isao Kaetsu 《Polymer Bulletin》2007,58(2):393-400
Summary Poly(proline) and random copolypeptide composed of Pro and Ala residues were synthesized, and their solution properties and
molecular conformation were investigated. Aqueous solutions of the polypeptide were irradiated with γ-rays above the transition
temperature. It was shown that the transition temperature of the aqueous solution of the copolypeptide is influenced by Ala-residue
content and γ-ray irradiation. 相似文献
66.
Nakazawa M. Okamoto S. Omiya T. Kasai K. Yoshida M. 《Photonics Technology Letters, IEEE》2010,22(3):185-187
67.
A facile approach to the fabrication of ultrathin polymer films on a flat or curved substrate is presented. Polymers with unsaturated pendant groups were spin-coated on a photoinitiator tethered surface, which was then photoirradiated and washed with a solvent. The obtained films were uniform, smooth (Ra < 0.2 nm) and exhibited robustness toward solvents. The thickness of the films was determined by the molecular weight of the coated polymer and was not dependent on the initial spin-coated thickness. A mechanism for the formation of the ultrathin film and application to optical lenses is presented. 相似文献
68.
Field profiles, equivalent isotropic radiated power (EIRP), beamwidth, and sidelobe levels of a quasi-optical power-combining grid amplifier structure are obtained using a whole-field electromagnetic analysis of a finite structure. This is efficiently obtained using a mixed spectral- and spatial-domain method-of-moments technique. It is seen that edge effects can have a significant effect on system performance 相似文献
69.
Masatake Yamaguchi Ken-Ichi Ebihara Mitsuhiro Itakura Tomoko Kadoyoshi Tomoaki Suzudo Hideo Kaburaki 《Metallurgical and Materials Transactions A》2011,42(2):330-339
The microscopic mechanism of grain boundary (GB) embrittlement in metals by hydrogen segregation (trapping) has been not well
understood for many years. From first-principles calculations, we show here that the calculated cohesive energy of bcc Fe
Σ3(111) and fcc Al(Cu) Σ5(012) symmetrical tilt GBs can be significantly reduced if many hydrogen atoms segregate at the GBs.
This indicates that the reduction of the cohesive energy of the GB may cause the hydrogen-induced GB embrittlement in Fe,
Al, and Cu. Considering the “mobile” effect of hydrogen during fracture, especially for the Fe system, more hydrogen atoms
coming from solid solution state can segregate on the gradually formed two fracture surfaces and reduce further the cohesive
energy. We suggest a new idea about the upper and lower critical stresses observed in the constant-load test of hydrogen-induced
delayed fracture in high-strength steels; the upper critical stress is determined by the amount (density) of “immobile” hydrogen
atoms segregated at the GB before fracture, and the lower critical stress is determined by the total amount (density) of immobile
and mobile hydrogen atoms, the latter of which segregate on the two fracture surfaces during fracture. 相似文献
70.
Magnetic properties of metal layer deposited by reduction of metal ions contained in polymer with applying magnetic field 总被引:5,自引:0,他引:5
Mitsuhiro Shibata Hiroshi Beniya Ryutoku Yosomiya Takatoshi Yosomiya 《Journal of Polymer Research》2000,7(1):57-61
Metal layer was deposited by the reduction of NiCl2 and CoCl2 in polyacrylonitrile film after applying an external magnetic field in directions parallel and perpendicular to the surface
of the film; the magnetic properties of the metal-deposited film were investigated. When the parallel magnetic field was applied,
the values of coercivity (Hc), remanent flux density (Br) and maximum flux density (Bs) increased regardless of the composition of the metal ions, compared with the case without the application of the magnetic
field. From the scanning electron micrographs and X-ray diffraction analyses, it was shown that the growth of crystalline
orientation in the deposited metals was enhanced by applying a parallel magnetic field. 相似文献