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41.
Kusumoto M Suzuki R Nishiya Y Okitsu T Oka M 《Journal of Bioscience and Bioengineering》2004,97(6):406-411
IS1203v is an insertion sequence (IS) which is identical to the most abundant IS elements in the genome of Escherichia coli O157:H7. However, there is no sequence homologous to IS1203v in the genome of E. coli K-12. We constructed a system to analyze the excision frequency of IS1203v, and demonstrated that the frequency in E. coli O157:H7 was approximately 10(5) times higher than that in E. coli K-12. We also investigated the excision frequencies of IS1203v in various E. coli isolates, and showed that the excision frequencies of IS1203v-possessing strains were approximately 10(3) times higher than those of IS1203v-nonpossessing strains. The results suggest that the IS1203v-possessing strains use a common system to enhance IS1203v excision. 相似文献
42.
Hiding image data with a material such as a light-scattering medium is useful as an initial stage of data protection, because the hidden image can be detected only by observation with a specific technique. A light-scattering medium is used to hide the image data, and a low-temporal-coherence interferometer performs the readout processing. A new readout method for detecting pixel values of the image is proposed to overcome spatial variation of the light intensity and distortion of the interference fringes. The introduction of spatial coding further improves the performance by overcoming spatial variations of the light-scattering medium and variations in the reflectance of given pixels. 相似文献
43.
44.
All-optical wavelength conversion employing a GaInAsP/InP nonlinear distributed-feedback waveguide switch is investigated. The device has the advantages of simple structure, compactness, polarity-noninverted operation, and feasibility of integration with other photonic devices such as semiconductor optical amplifier and modulators. We show that the device exhibits constant conversion efficiency around -9.2 dB in a signal-wavelength range of 1530-1560 nm. Furthermore, this device can potentially be made polarization independent. 相似文献
45.
46.
Kazutomo Hoshino Yoshiaki IIjima Ken-Ichi Hirano 《Metallurgical and Materials Transactions A》1982,13(7):1135-1139
Interdiffusion coefficients in copper-rich copper-zinc solid solutions containing up to 8 at. pct of Zn at 1168 K have been
determined by Matano's analysis using semi-infinite diffusion couples consisting of pure copper and Cu-Zn alloys with Kirkendall
markers. From the marker shift and Darken's relation, intrinsic diffusion coefficients, DZn and DCu, in the alloys containing 3.2 and 4.7 at. pct of Zn have been determined. Further, using thin plate couples, DZn and DCu in Cu alloys containing 0.9, 2.3, 3.5, and 4.6 at. pct of Zn at 1168 K have been determined by Heumann's method. The ratio
of the intrinsic diffusion coefficients, DZn/DCu, has been found to be about two for all the compositions examined. Using the values of the intrinsic diffusion coefficient
of copper at infinite dilution of zinc obtained by extrapolating the concentration dependence of DCu, and the self- and impurity diffusion coefficients in pure copper, the vacancy flow factor has been estimated to be - 0.22-0.15
+0.06 at 1168 K. By combining this value of the vacancy flow factor with the solute enhancement factor of solvent diffusion determined
by Peterson and Rothman, the correlation factor for impurity diffusion of Zn in Cu at 1168 K has been evaluated to be 0.5,
which is in good agreement with the value of 0.47 determined by Peterson and Rothman based on the isotope effect measurement.
KAZUTOMO HOSHINO, formerly Graduate Student, Tohoku University is now with Materials Science Division, Argonne National Laboratory,
Argonne, IL 60439. YOSHIAKI IIJIMA, Instructor, and KENICHI HIRANO, Professor, are both with the Department of Materials Science,
Faculty of Engineering, Tohoku University, Sendai 980, Japan. 相似文献
47.
48.
Yuichiro Ezoe Ikuyuki Mitsuishi Utako Takagi Masaki Koshiishi Kazuhisa Mitsuda Noriko Y. Yamasaki Takaya Ohashi Fumiki Kato Susumu Sugiyama Raul E. Riveros Hitomi Yamaguchi Shinya Fujihira Yoshiaki Kanamori Kohei Morishita Kazuo Nakajima Ryutaro Maeda 《Microsystem Technologies》2010,16(8-9):1633-1641
We are developing novel ultra light-weight and high-resolution X-ray micro pore optics for space X-ray telescopes. In our method, curvilinear micro pore structures are firstly fabricated by silicon deep reactive ion etching (DRIE) or X-ray LIGA processes. Secondly, side walls of the micro structures are smoothed by magnetic field assisted finishing and/or hydrogen annealing techniques for high reflectivity mirrors. Thirdly, to focus parallel X-ray lights from astronomical objects, these structures are elastically or plastically bent into a spherical shape. Fourthly, the bent structures are stacked to form a multi-stage X-ray telescope. In this paper, we report on fabrication and X-ray reflection tests of silicon and nickel X-ray mirrors using the DRIE and LIGA processes, respectively. For the first time, X-ray reflections were confirmed on both of the mirrors. Estimated rms roughnesses were 5 nm and 3 nm for the silicon and nickel mirrors, respectively. 相似文献
49.
50.
Thermotropic liquid-crystalline compounds were applied as membrane materials (membrane solvent and neutral carrier) for neutral carrier-type ion sensors to investigate how the ordered arrangement of neutral carriers affects the property of the resulting ion sensors. Nematic, smectic, and cholesteric liquid-crystalline compounds were used as the membrane solvents and crown ether derivatives with a molecular structure similar to the liquid-crystalline solvent as the K+ neutral carriers. Polarized IR spectroscopy and X-ray diffraction experiments confirmed that the highly ordered arrangement of membrane components was retained in the liquid-crystal-based ion-sensing membranes containing a neutral carrier and a lipophilic salt. The ordered arrangement of neutral carriers in the liquid-crystalline membranes enhanced the ion selectivity significantly, probably due to the efficient cooperation of two adjacent crown ether moieties in the highly ordered and aggregated state. 相似文献