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141.
分解方法是处理复杂问题常用的一种手段,而差分进化算法被广泛地应用于多目标优化问题(multiobjective optimization problems,MOP),为了克服经典差分进化算法和分解方法的缺陷,本文提出了一种自适应差分进化算法和变邻域分解方法相结合的新颖算法一ADEMO/D-ENS,该算法采用Tchebycheff方法将多目标优化问题分解成多维标量优化子问题,并利用邻域子问题的信息进行优化,基于邻域种群集依概率自适应选择邻域种群规模;同时采用概率匹配(]probability match,PM)自适应方法从差分策略池中选择差分进化策略;同时分析了算法的复杂度;最后,通过和经典的非支配排序遗传算法(non-dominated sorting genetic algorithmsⅡ,NSGA-Ⅱ)和多目标差分进化算法(multi-objective differential evolution algorithm,MODE)仿真对比,说明ADEMO/D-ENS方法可以更有效的处理多目标优化问题. 相似文献
142.
The solid solution of CaTi1−x
Zr
x
O3 (x = 0–0.15) was successfully synthesized by the polymerized complex (PC) method. This study has exhibited the advantage of
the PC method to prepare a highly active CaTiO3 compared with the conventional solid-state reaction (SSR) method. More importantly, further improvement in phase purity and
large surface area was achieved by the doping of Zr4+, leading to remarkable enhancement of photocatalytic activities compared to pure CaTiO3. The quantum yield for H2 evolution over the most active photocatalyst, Pt (1.0 wt%)/CaTi0.93Zr0.07O3, was 1.91% and 13.3% in photoreactions from pure water and aqueous ethanol solution, respectively for 0.1 g photocatalyst,
which was about 3.3 and 2.5 times compared to that of PC-derived CaTiO3. 相似文献
143.
L. Smith 《Chemical engineering science》2004,59(15):3223-3234
We demonstrate the enhanced capacities of our analysis toolset for three-dimensional data. In particular, we provide supporting evidence for some of the conclusions reached in our previous studies of two-dimensional avalanching heaps. Segregation by self-diffusion is shown to take place in three-dimensional assemblies and self-diffusion velocities are shown to be of a comparable order of magnitude to those found in plane-strain situations. The effect on assembly evolution by discrete avalanching of the availability of a third dimension for translation is investigated. The discrete wavelet transform is again shown to be a useful component of the toolset in coupling process variables in the context of the discrete defining events associated with assembly evolution. In particular, we move towards the determination of time constants by correlating wavelet coefficients with a time shift. 相似文献
144.
针对多目标分布估计算法全局收敛性较弱的缺陷,提出了一种自适应混合多目标分布估计进化算法。其基本思想是:在多目标分布估计算法中引入全局收敛性较强的差分进化算法,当函数变化率较大时,用分布估计算法产生新种群;当函数变化率较小即算法可能陷入局部收敛时,用差分进化算法产生新种群。理论分析和数值实验结果表明,这种混合算法不仅具有良好的全局收敛性,而且解的分布性和均匀性较没有考虑目标函数变化率的混合多目标分布估计算法也有了一定程度的提高。 相似文献
145.
O. G. Glotov 《Combustion, Explosion, and Shock Waves》2006,42(4):436-449
The condensed combustion products of two model propellants consisting of ammonium perchlorate, aluminum, nitramine, and an
energetic binder were studied by a sampling method. One of the propellants contained HMX with a particle size D
10 ≈ 490 μm, and the other RDX with a particle size D
10 ≈ 380 μm. The particle-size distribution and the content of metallic aluminum in particles of condensed combustion products
with a particle size of 1.2 μm to the maximum particle size in the pressure range of 0.1–6.5 MPa were determined with variation
in the particle quenching distance from the burning surface to 100 mm. For agglomerates, dependences of the incompleteness
of aluminum combustion on the residence time in the propellant flame were obtained. The RDX-based propellant is characterized
by more severe agglomeration than the HMX-based propellant — the agglomerate size and mass are larger and the aluminum burnout
proceeds more slowly. The ratio of the mass of the oxide accumulated on the agglomerates to the total mass of the oxide formed
is determined. The agglomerate size is shown to be the main physical factor that governs the accumulation of the oxide on
the burning agglomerate.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 4, pp. 78–92, July–August, 2006. 相似文献
146.
Keiji Kunimatsu Takahiro Senzaki Minoru Tsushima Masatoshi Osawa 《Electrochimica acta》2007,52(18):5715-5724
Hydrogen evolution reaction (HER) on a polycrystalline Pt electrode has been investigated in Ar-purged acids by surface-enhanced infrared absorption spectroscopy and electrochemical kinetic analysis (Tafel plot). A vibrational mode characteristic to H atom adsorbed at atop sites (terminal H) was observed at 2080-2095 cm−1. This band appears at 0.1 V (RHE) and grows at more negative potentials in parallel to the increase in hydrogen evolution current. Good signal-to-noise ratio of the spectra enabled us to establish the quantitative relation between the band intensity (equivalently, coverage) of terminal H and the kinetics of HER, from which we conclude that terminal H atom is the reaction intermediate in HER and the recombination of two terminal H atoms is the rate-determining step. The quantitative analysis of the infrared data also revealed that the adsorption of terminal H follows the Frumkin isotherm with repulsive interaction. 相似文献
147.
148.
The PbO2 and F−-doped PbO2 (F-PbO2) film electrodes have been prepared by an electrodeposition process onto platinum substrate. The changes of their electrochemical activity for oxygen evolution (OE) reaction with accelerated electrolysis time have been studied. The results show that the activity of the electrodes decreases with increasing electrolysis time. This can be attributed to the conductivity variations, which are caused by the decrease of the oxygen vacancy concentration in PbO2 films during OE. The mechanism of the decrease of the oxygen vacancies has been investigated. For F-PbO2 film electrodes, though its electrochemical activity is somewhat lower than that of undoped one, its activity stability is much higher in comparison with that of PbO2. The influence of F− doping on the activity of PbO2 film electrodes has been also discussed. 相似文献
149.
The H2 evolution reaction from an aqueous Na2SO3 solution proceeded with 3.7% quantum yield under visible light irradiation (λ > 420 nm) on a Zn0.957Cu0.043S solid solution photocatalyst without co‐catalysts such as Pt.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
150.
In aluminium plants, the anode baking process is associated with an important release of volatile combustible matter. It is the purpose of this study to investigate the kinetics of the evolution of these volatiles. A large thermogravimetry set-up has been designed in such a way that it could simulate real plant conditions. Samples of two distinct masses have been subjected to pyrolysis at different heating regimes. The loss of weight together with the concentrations of the released gases were recorded on a continuous basis during the temperature rise. Kinetic results were found for methane, hydrogen and tar. No variation of the order of reaction with the heating rate was observed, whereas the activation energy and the pre-exponential factor increased. Furthermore, for the range of sample dimensions studied, it was found that the mass of the solid had no significant influence on the kinetic parameters. 相似文献