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171.
172.
Heishiciro Takahama Hitoshi Kawamura Seizo Kato Hajime Yokosawa 《International Journal of Engineering Science》1979,17(6):735-744
Energy separation performance of a steam-operated vortex tube is experimentally investigated, and some reasonable criteria and expressions to estimate the energy separation performance are also introduced. The performance characteristics defined by the above expressions are the same as those of ideal gas in the high superheated region, and are well expressed independently of the degree of superheat, total mass flow rate and discharge resistance. When steam is in the wet region at the nozzle outlet, the performance considerably decreases because of the energy waste from moisture vaporization. And no energy is separated when the dryness fraction is less than approximately 0.98. Some technical data including the optimum operating conditions are also offered. 相似文献
173.
Toshiaki Tanaka Hitoshi Kawaji Tooru Atake Koichi Kikuchi Kazuya Saito Shinzo Suzuki Yohji Achiba Isao Ikemoto 《Fullerenes, Nanotubes and Carbon Nanostructures》1994,2(2):121-127
The heat capacity of C70 has been measured by adiabatic calorimetry between 14 and 320 K. The orientational phase transition is observed as a broad hump in the heat capacity curve, which is strongly influenced by small amount of solvent remaining in the sample. 相似文献
174.
A new dislocation model is constructed on the basis of various characteristics of dislocations revealed by X-ray diffraction topography, for interpreting plastic deformation behaviour of ice single crystals in basal glide. The model of a pair of screw dislocation arrays of opposite sign exhibits resistance for the movement, which depends upon both the configuration and the stress. Orowan's relation between the macroscopic strain rate and characteristic of dislocations in the crystal (density and velocity) is rewritten in a dynamical style taking into account the resisting stress and the empirically established linear relationship between the dislocation velocity and the stress. In this formulation, a new concept of fractional dislocation density is introduced.Examples of fractional density as a function of maximum stress are obtained from our stress relaxation experiments. Assuming that the initial fractional density profile for a fresh ice single crystal is similar to those obtained above, stress-strain curves are calculated numerically for various crosshead speeds of the test machine. Computed results coincide well with the characteristic stress-strain curves previously obtained experimentally. 相似文献
175.
This paper reviews recent research in molecular dynamics studies of the traction properties of hydrocarbon fluids under elastohydrodynamic lubrication, focusing on the technical problems that arise on making predictions of the traction properties of an oil film with a submicron thickness at the actual sliding contacts of the machine elements by at a nanoscale molecular simulation. The effect of the oil film thickness and shear rate are examined including the result of a submicron thickness simulation of the oil film using a tera‐flops computer. The mechanism of the phase transition of the fluids under high pressure, the boundary slip, and the momentum transfer related to the molecular structure of the fluids are also presented. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
176.
Daisuke Yasokawa Satomi Murata Yumiko Iwahashi Emiko Kitagawa Katsuyuki Kishi Yukihiro Okumura Hitoshi Iwahashi 《Journal of Bioscience and Bioengineering》2010,109(5):479-486
Zinc pyrithione has been used in anti-dandruff shampoos and in anti-fouling paint on ships. However, little is known of its mode of action. We characterized the effects of sub-lethal concentrations of zinc pyrithione (Zpt) on Saccharomyces cerevisiae using DNA microarrays. The majority of the strongly upregulated genes are related to iron transport, and many of the strongly downregulated genes are related to the biosynthesis of cytochrome (heme). These data suggest that Zpt induces severe iron starvation. To confirm the DNA microarray data, we supplemented cultures containing Zpt with iron, and the growth of the yeast was restored significantly. From these results, we propose that the principal toxicity of zinc pyrithione arises from iron starvation. 相似文献
177.
Kiyofumi Katagiri Hitoshi Inami Tomohide Ishikawa Kunihito Koumoto 《Journal of the American Ceramic Society》2009,92(S1):S181-S184
A low-temperature procedure for the synthesis of TiO2 was developed using a water-soluble titanium complex and enzymes. Titanium–lactate and titanium–glycolate complexes were used as precursors of TiO2 . Digestive enzymes were chosen as biocatalysts for the synthesis of TiO2 in aqueous solutions. TiO2 powders were deposited from reaction solutions having optimal pH values for the enzymes to exhibit their catalytic activities for their original substrates. TiO2 has been synthesized by an enzymatic reaction in an aqueous solution under ambient conditions. The XRD measurements indicated that TiO2 powders thus obtained usually have an amorphous phase. However, after calcination at 550°C, the anatase phase was confirmed. Interestingly, the minor phase of TiO2 , brookite, was found in the sample obtained from the titanium–glycolate complex catalyzed by lipase at pH 10 after calcination at 550°C. 相似文献
178.
We prepared ultrafine Fe–Pt alloy nanoparticle colloids by UV laser solution photolysis (KrF excimer laser of 248 nm wavelength)
using precursors of methanol solutions into which iron and platinum complexes were dissolved together with PVP dispersant
to prevent aggregations. From TEM observations, the Fe–Pt nanoparticles were found to be composed of disordered FCC A1 phase
with average diameters of 0.5–3 nm regardless of the preparation conditions. Higher iron compositions of nanoparticles require
irradiations of higher laser pulse energies typically more than 350 mJ, which is considered to be due to the difficulty in
dissociation of Fe(III) acetylacetonate compared with Pt(II) acetylacetonate. Au colloid preparation by the same method was
also attempted, resulting in Au nanoparticle colloids with over 10 times larger diameters than the Fe–Pt nanoparticles and
UV–visible absorption peaks around 530 nm that originate from the surface plasmon resonance. Differences between the Fe–Pt
and Au nanoparticles prepared by the KrF excimer laser solution photolysis are also discussed. 相似文献
179.
Mamoru Ishida Takeo Uehara Toshio Arai Hideki Takeda Tadashi Yamaguchi Takeshi Taniguchi Tetsuya Katsumi Masayuki Kobayashi Hitoshi Ofune 《Intermetallics》2002,10(11-12)
The performance of MU/SC conversion sleeve produced by bulk metallic glass (Zr55Al10Ni5Cu30) was examined. A precision die-casting method was applied to improve size accuracy. The size accuracy of the conversion sleeve produced by the precision die-casting method was ±1 μm, and optical insertion loss (Li) was less than 0.3 dB for a standard value. The wear resistance of metallic glass is improved by surface oxidation treatment in air at 673 K. The MU/SC conversion sleeve produced from bulk metallic glass has superior characteristics for optical parts. 相似文献
180.
Murata H Futami J Kitazoe M Kosaka M Tada H Seno M Yamada H 《Journal of Bioscience and Bioengineering》2008,105(1):34-38
Polyethylenimine (PEI) cationization is a powerful strategy for protein transduction into cells. In this study, we attempted the artificial regulation of cell proliferation by protein transduction of the N-terminal domain (1-132 amino acids) of the simian virus 40 large T-antigen (SVLT-N), which inactivates retinoblastoma family proteins but not p53. To deliver SVLT-N into cells, we employed an indirect cationization method by forming a complex of biotynylated SVLT-N through disulfide bonds (biotin-SS-SVLT-N) and PEI-cationized avidin (PEI600-avidin). Using this complex, SVLT-N was transduced into the nucleus of confluent and quiescent Balb/c 3T3 cells and was found to be complexed with a cellular target protein, pRb. Furthermore, SVLT-N transduction induced cell proliferation in spite of confluent conditions. Because SVLT-N thus transduced into cells gradually degraded and was not detectable after a 4-d incubation, transiently transformed cells were obtained by this method. These results suggest that oncogene protein transduction technology has great potential for in vitro regulation of cell proliferation. 相似文献