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1.
《International Journal of Hydrogen Energy》2022,47(51):21753-21759
Surface reconstruction produces metal oxyhydroxide (1OOH) active sites, and promoting surface reconstruction is essential for the design of OER electrocatalysts. In this paper, we reported that a large amount of active NiFeOOH was generated in-situ on the surface of nickel-iron sulfide selenide, thus exposing more active sites and efficiently catalyzing OER. In 1 M KOH solution, NiFeOOH(S,Se) achieves an ultra-low overpotential of 195 mV at the current density of 10 mA cm?2, and the Tafel slope is only 31.99 mV dec?1, showing excellent catalytic performance. When the current density is 100 mA cm?2, the over-potential of NiFeOOH(S,Se) in KOH + seawater solution is 239 mV, which is almost equivalent to 231 mV in KOH solution. The excellent OER stability of the NiFeOOH(S,Se) catalyst in alkaline electrolytes was confirmed, and the overpotential did not change significantly after 4 days of testing in KOH + seawater solution. 相似文献
3.
Propylene molecule owns two active sites, the direct epoxidation of propylene by dioxygen is still a challenge due to the limitation of selectivity. In this work, the direct liquid-phase propylene aerobic epoxidation protocol by chloride manganese meso-tetraphenylporphyrin (MnTPPCl) was developed. The conversion of propylene was 12.7%, and the selectivity towards PO (propylene oxide) reached up to 80.5%. The formation of PO was attributed to the mechanism via high-valent Mn species, which was confirmed by means of in situ UV–vis spectrum. 相似文献
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Multimedia Tools and Applications - Subspace-based models have been widely applied for hyperspectral imagery applications, especially for classification. The main principle of these methods is... 相似文献
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OR Spectrum - This paper studies a multi-period investment–consumption optimization problem with a stochastic discount rate and a time-varying utility function, which are governed by a... 相似文献
7.
《中国稀土学报(英文版)》2020,38(5):571-576
The Eu(III) nitrate complex of the meso- N,N′-bis(2-pyridylmethylene)-1,2-(R,S)-cyclohexanediamine ligand was synthesized and characterized by single crystal and powder X-ray diffraction. The crystal lattice of the complex is capable of absorbing and desorbing selectively acetonitrile molecules, at 293 K upon an acetonitrile vapor pressure of ∼0.1 × 105 Pa. This process, which is partially reversible, can be easily followed by both powder X-ray diffraction (P-XRD) and Eu(III) luminescence spectroscopy. The acetonitrile molecule, located in the outer coordination sphere of the metal ion, does not affect the radiative transition probability of 5D0 level of Eu(III) and also it does not activate further non-radiative channels from this level. On the other hand, this molecule is capable of affecting the energy position and intensities of the crystal field components of the 5D0→7F2 transition. The complex in solid form can be considered a promising material for the optical sensing of acetonitrile vapors. 相似文献
8.
The development of traditional urbanisation has generated environmental problems, so the Chinese Government has proposed a new-type of urbanisation path with uniquely Chinese characteristics. How does this new-type of urbanisation affect CO2 emissions? Based on panel data from 29 provinces in China (2005 to 2016), we apply an exploratory spatial data analysis model, a spatial econometric model, and a threshold model to analyse the spatial autocorrelation of CO2 emissions, the direct and indirect effects of new-type urbanisation on CO2 emissions, and the threshold characteristics produced by technological progress, respectively. The key results are: (1) CO2 emissions show significant positive autocorrelation in China, and the spatial distribution of CO2 emissions is HH (High-High) or LL (Low-Low) clustered in most provinces; (2) new-type urbanisation has a paradoxical effect on CO2 emissions. Energy-saving technology has a rebound effect on CO2 emissions, but environmental technology inhibits CO2 emissions; (3) by eliminating the rebound effect of energy-saving technology on CO2 emissions and promoting environmental technology, new-type urbanisation indirectly inhibits CO2 emissions; (4) new-type urbanisation exhibits a threshold effect on CO2 emissions due to the different levels of energy-saving technology and environmental technology. Finally, policy recommendations for CO2 emissions reduction are proposed from the perspective of new-type urbanisation, energy-saving technology, and environmental technology. 相似文献
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Collection and transportation of solid waste are costly for municipal budgets. This study challenges the use of existing administrative boundaries in waste management applications. By reducing the spread (standard deviation) of parameters (landfills, populated places, and roads), efficient and practical waste management regions are created. A novel alteration to the Centroidal Voronoi Tessellation (CVT) algorithm is proposed where Thiessen polygons are created using the central feature of a subset of data instead of the geometric centroid. The results applying the central feature method are compared to traditional CVT methods. Two Canadian provinces (Saskatchewan and Nova Scotia), the City of Regina, and two New York City boroughs (Manhattan and the Bronx) are investigated. Results suggest that the newly proposed tool can reduce the standard deviation of selected parameters compared to CVT. The spatial distribution of data and the geometry of the input tessellations are important factors in optimization. In Saskatchewan, reductions in parameter standard deviations ranged between 7.0 and 23.8% when comparing the two methods. In Nova Scotia, reductions in standard deviation of 9.64–13.25% were observed. In the City of Regina, wards may be more effective in planning solid waste collection compared to current solid waste collection boundaries. The standard deviation of parameters was minimized by 32.2–55.0% in New York. The proposed method may be able to efficiently create waste management regions in both cities and provinces, helping to reduce waste collection and transportation costs by ensuring an even spread of parameters in each region. 相似文献