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红粘土型金矿是黔西南的一个重要的金矿类型,我们以往的研究实践表明:Aleks Kalinowski等[1]研制的红粘土型金矿ASTER波段比值4/5不适合黔西南红粘土的信息提取,因此,需要研究适合该地区的ASTER波段比值。ASTER波段比值组合2/1、4/3和(5+7)/6彩色合成后被成功地应用到研究区的红粘土提取中。比值的选择是建立在对矿区红粘土光谱曲线特征的分析和ASTER图像预处理的基础上,该比值组合能够有效提取出ASTER图像上的矿区红粘土信息,并可以扩展应用到周边地区,寻找到更多含金红粘土的分布区,这充分显示了ASTER波段比值彩色合成技术在红粘土提取中的作用。 相似文献
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运用业务流程重组的理论,以某集团企业为实例,论述了BPR在大型企业招标信息化建设中的重要作用,并从体制、制度、流程的重构几个层面,指导招标信息化建设。同时,也通过对招标信息化与业务流程重组实施相结合进行探讨,以期实现招标管理水平的有效提升。 相似文献
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Electron impact collision strengths and oscillator strengths for Ni-like Nd, Sm, Eu, Gd, Ta, and W ions 总被引:1,自引:0,他引:1
Jiaolong Zeng Jiayong Zhong Gang Zhao Jianmin Yuan 《Atomic Data and Nuclear Data Tables》2005,90(2):259-317
Energy levels, oscillator strengths, and electron impact collision strengths have been calculated for Ni-like ions of Nd (Z = 60), Sm (Z = 62), Eu (Z = 63), Gd (Z = 64), Ta (Z = 73), and W (Z = 74) among the 249 levels belonging to the ([Ne])3s23p63d10, 3s23p63d9nl, 3s23p53d10nl, 3s3p63d10nl (n = 4, 5; l = 0, 1, … , n − 1) configurations. Configuration interactions among these configurations have been included in the calculations. Collision strengths have been obtained at 20 scattered electron energies (5–20,000 eV) and they have been listed at six representative energies of 100, 400, 1000, 2500, 5000, and 10,000 eV in this work. Effective collision strengths have been obtained by assuming a Maxwellian electron velocity distribution at 24 temperatures ranging from 100 to 3000 eV. Our results are compared with those available in the literature. The relative difference is within 0.3% between our calculated energy levels and the corresponding experimental values wherever available. The energy levels are expected to be be accurate within 0.6%, while oscillator strengths and collision strengths for strong transitions are probably accurate to better than 20%. The complete dataset is available electronically from http://www.astronomy.csdb.cn/EIE/. 相似文献
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A new type of carbon-inorganic absorbent with good oil-removing performance is prepared by sintering and activating petrochemical sludge. Of the absorbents prepared by three different methods (non-activated, vapor /840 ℃/6 h, CO2/1 000 ℃/2 h), the one prepared by the second method is the best in oil-removing, which can remove 60% of oil from petrochemical wastewater with a concentration of 76.42 mg/L. X-ray Diffraction (XRD) analysis shows that the constituents of the adsorbents are basically similar to those of inorganic granulating materials, such as SiO2, Al2O3, orthoclase feldspar, iron ore, etc. Composition analysis reveals that the activated absorbent has a large specific surface area with a high carbon content in activated compositions and a good oil-removing capability. 相似文献
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An important requirement in the thermographic nondestructive evaluation is the identification of actual sound zone or the base line with which the defective areas are compared to determine the actual temperature contrast and the corresponding defect severity. In a part under inspection, the actual sound zone is not known a priori and various approximations have been used in the past to serve as this unknown base line. Determination of actual sound zone in a defective test object is still a challenge. A related issue before the identification of this base line pixel is in the elimination of non-uniformity in the temperature distribution across the specimen surface which is unrelated to the actual defects. This spurious contrast is often introduced by the limitations of the instrumentation or the test procedure and it has to be eliminated before pixels in the sound zone can be located. This paper presents an automated procedure for simultaneously eliminating spurious contrast and locating sound zone pixels, directly from experimental data in a thermographic nondestructive evaluation. Location of actual sound zone pixels facilitates accurate thermal contrast computations, extraction of thermal properties such as break time and thermal diffusivity. In addition, based on the actual sound zone temperature profile it is possible to normalize experimental thermographic results in such a way that they can be directly correlated with results from numerical simulations. 相似文献
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Peng Zhou Sijiang Xiong Yuxuan Zhang Hua Jiang Yongchao Chi Lei Li 《International Journal of Hydrogen Energy》2017,42(29):18181-18188
The nitrogen transformation with attention to the intermediates and NOx precursors has been investigated during the primary pyrolysis of sewage sludge by using Pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS) and Pyrolyzer-Fourier transform infrared spectrometry (Py-FTIR). A three-stage process of nitrogen transformation during the sewage sludge pyrolysis was suggested. The decomposition of labile protein and inorganic ammonium salt mainly occurred in the first stage (<300 °C), giving rise to a small amount of NH3. In the second stage (300–600 °C), the macromolecular protein firstly cracked into small molecular amine compounds, and then went through deamination process, contributed to a large release of NH3. In the third stage (600–900 °C), the amine compounds converted into nitriles, and generated a large amount of HCN, while the formation of NH3 slowed down accordingly. 相似文献