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91.
The paper presents a method for obtaining an optimal reliability allocation of an n-stage series system. In each stage, redundant comnponents can be added (in parallel, stand-by, or k-out-of-n:G, etc.), or a more reliable component can be used in order to improve the system reliability. The solution is obtained by repeatedly using a more reliable candidate at each stage that has the greatest value of a `weighted sensitivity function'. The balance between the objective unction and the constraints is controlled by a `balancing coefficient'. The overall computational procedure is given and an example is presented. The computations are given for a set of randomly generated test problems in which the optimal parallel redundancy under linear onstraints is determined. The proposed method is then compared with other methods. 相似文献
92.
A neutronic analysis of the laser-driven inertial-confinement fusion reactor SENRI-I is presented. Three-dimensional Monte Carlo calculations were performed to examine the effects of laser beam ports on the flux distribution, tritium breeding ratio, thermal energy deposition in the blanket, and radiation streaming. A Monte Carlo code was also used for the time-dependent radiation-damage analysis accounting for the time of the flight spread of neutrons and the results are compared to the analysis for the HIBALL design. Induced radioactivity was estimated, based on the one-dimensional transport calculation and depletion analysis. The calculated results reveal the advantages of the SENRI-I design with a thick Li layer compared to other reactor systems employing a dry-wall scheme. 相似文献
93.
E Noguchi N Hayashi Y Azuma T Seki M Nakamura N Nakashima M Yanagida X He U Mueller S Sazer T Nishimoto 《Canadian Metallurgical Quarterly》1996,15(20):5595-5605
Using the two-hybrid method, we isolated a Saccharomyces cerevisiae cDNA encoding a protein homologous to Schizosaccharomyces pombe protein Dis3sp, using as bait, human GTPase Ran. The DIS3 gene is essential for viability and complements S.pombe mutant dis3-54 which is defective in mitosis. Although Dis3sc has no homology to RanBP1, it bound directly to Ran and the S.cerevisiae Ran homologue Cnr1, but not to the S.cerevisiae RCC1 homologue Srm1. Upon binding to Ran with a 1:1 molar ratio, Dis3sc enhanced a nucleotide-releasing activity of RCC1 on Ran. In the presence of Dis3sc, the K(m) of RCC1 on Ran decreased by half, while the kcat was unchanged. In vivo, Dis3sp was present as oligomers of M(r) 670-200 kDa as previously reported, and the 200 kDa oligomer of Dis3sp was found to include Spi1 and Pim1, the S.pombe homologues of Ran and RCC1, respectively. Although the biological function of the heterotrimeric oligomer consisting of Dis3, Spi1 and Pim1 is unknown, our results indicate that Dis3 is a component of the RCC1-Ran pathway. 相似文献
94.
Position-dependent optimization calculations have been carried out on a D-D fusion reactor blanket/shield to maximize the energy gain in the blanket and to minimize the atomic displacement rate of the copper stabilizer in the superconducting magnet. The results obtained by using the optimization code SWAN indicate (1) the advantage of D2O coolant over H2O coolant with respect to increasing the energy gain, and (2) the difference in the optimal shield distributions between D-T and D-D neutron sources. The possibility of improving both the energy gain and radiation shielding characteristics is also discussed. 相似文献
95.
The paper analyzes logic-trees containing mutually exclusive primary events. A logic-tree is similar to a fault-tree, but can contain successes as well as failures. s-Coherent structure function and other basic terms are defined. Some useful properties of s-coherent structure functions are presented which include, as special cases, the previous results for logic-trees containing no mutually exclusive primary events. A method is provided for obtaining an effective upper bound to probability of occurrence of the top event for logic-trees with s-noncoherent structure functions. 相似文献
96.
The temperature dependence of the stress in each layer of a film system comprising chemically vapour-deposited phosphosilicate glass (PSG) on an AlSi alloy film on a silicon substrate was investigated in the range 20–500°C. During a heating process in which the temperature exceeded 150°C, the deformation of the AlSi film was found to be caused by diffusional creep, and the stresses in both the AlSi film and the PSG film increased with increasing silicon concentration in the AlSi film. Deformation of AlSi film during a cooling process in which temperatures were higher than 150°C was found to be caused by the generation of dislocation loops or by grain boundary sliding. These phenomena are interpreted as representing relaxation of the total elastic energy of the system which results from the deformation of the AlSi film. 相似文献
97.
Nakamura H Miura T Numajiri M Nakao N Nakashima H Matsuda N Watanabe S 《Radiation protection dosimetry》2005,116(1-4 PT 2):252-255
The doses of radiation streaming through a labyrinth were measured using thermoluminescence dosemeters (TLDs) and neutron moderators for TLDs at the neutrino beam line of the 12 GeV proton accelerator facility of High Energy Accelerator Research Organization (KEK). The calculated doses using the Monte Carlo code, MCNPX basically agreed with the experimental results. However, unexpectedly, the calculated neutron doses were smaller than the measured ones along the upstream side of the labyrinth. 相似文献
98.
In situ high-temperature visible microspectroscopy has been developed in order to study color change kinetics of volcanic materials. Olivine thin sections put on a synthetic alumina plate are heated on a heating stage at 600-800 degrees C under a visible microspectroscope. Changes in visible absorption spectra are monitored every 60 s for 5 hours. The obtained high-temperature visible spectra showed a gradual increase with time in absorbance in the shorter wavelength region (400-600 nm). The 430 nm absorbance (ligand field transition of Fe3+ increased more with time at higher temperatures. Assuming diffusional transport in plane sheets, apparent diffusion coefficients were determined at temperatures of 600-800 degrees C. The activation energy for this diffusion in olivine is 208 +/- 17 kJ/mol. This activation energy value is similar to those for the metal vacancy diffusion in olivine. This newly developed in situ high-temperature visible microspectroscopy can provide kinetic measurements of visible spectral change of materials at high temperatures such as volcanic materials. 相似文献
99.
100.