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1.
用HFR方法对CaⅨ-KrⅩⅩⅤ离子3s2,3s3p,3s3d,3p2组态能级结构进行了理论计算.在已有实验研究的基础上,通过分析离子能级沿等电子序列的变化规律,运用最小二乘拟合方法预言计算了GeⅩⅪ-SeⅩⅩⅢ离子3s2,3s3p,3s3d,3p2组态14条精细结构能级值.在此基础上,进一步计算了GeⅩⅪ-SeⅩⅩⅢ离子3s2-3s3p,3s3p-3s3d和3s3p-3p2跃迁的23条谱线波长和相应的振子强度.计算结果与已有的实验值十分吻合,波长的最大不确定度为0.008 nm. 相似文献
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驻极体声传感器及其储电材料的现状 总被引:1,自引:0,他引:1
综述了驻极体声传感器及其储电材料近年来的迅猛发展。传统的FEP(tetrafluoroethylene—hexa—fluoropropylene copolymer)极体电容式声传感器及以铁电聚合物PVDF(poly vinylidene fluoride)家族为芯片的声传感器和超声抉能器仍焕发着青春活力。Si基微型驻极体声传感器的理论和实验研究已经日趋成熟,而用空间电荷型多孔聚合物驻极体压电薄膜为芯片可望研制出新一代声电和电声传感器、压力传感器和驱动器。 相似文献
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Pinning effect of lead lanthanum titanate (PLT) ferroelectric thin films with excess PbO of 20 mol% has been studied for deposition on diffe rent substrates. Silicon, sapphire and quartz were used as substrates on which P t/Ti or LaNiO3 thin films were deposited as bottom electrodes. Electron probe analysis results showed that there was still a certain amount of excess Pb in PLT films after annealing at 550 ℃ for 1 h, and the amount of it was dependent on the substrate used. The distribution of excess Pb in the films was investig ated by Auger electron spectroscopy depth profile. It was shown that the substrates and the bottom electrodes had significant effects on the content and distrib ution of excess Pb in PLT films. The excess Pb and its accumulation at the inter face between the film and bottom electrode may act as pinning centers and have a pinning effect on domains, which can be observed by abnormal P-E hysteresis loops and abnormal C-V curves. The excess Pb content in the films and the accumulation of Pb at the interface were high in PLT films deposited on Pt/Ti/S i, and considerable pinning effect was observed. As LaNiO3 would absorb most part of the excess Pb in PLT films, the content of excess Pb in the films deposited on LaNiO3/Si was very low and the pinning effect was hardly observed. 相似文献
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采用纳米化学技术制备了新型的纳米复合固体超强酸催化剂SO42-/ZrO2-Fe2O3,并用XRD、TEM进行了表征.结果表明:所研制的SO42-/ZrO2-Fe2O3催化剂为晶态纳米粒子,平均粒径为30 nm,分散性较好;当活化温度为580℃,反应温度为75℃,n(硝酸)/n(苯)=2,m(苯)/m(催化剂)=20,催化反应时间5 h时,硝基苯收率可达89.6%. 相似文献
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XI Jingyu QIU Xinping ZHU Wentao & CHEN Liquan Department of Chemistry Tsinghua University Beijing China 《中国科学B辑(英文版)》2005,48(6)
All solid-state lithium polymer batteries may be one of the best choices for the future electrochemical power source, characterized by high energy densities, good cyclability, reliability and safety[1,2]. Owing to its potential capability to replace the t… 相似文献
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红外全息技术更适用于长距离的大视场成像,但其散斑噪声与高斯噪声对图像质量的影响也更加显著,限制了红外全息技术的应用与推广。本文通过引入全局傅立叶阈值与自适应维纳滤波的方法对三维块匹配滤波算法进行优化,提高了其对红外全息图像降噪的适应性与细节保留,得到改进的三维块匹配滤波算法,并与多种采用传统滤波方法的结果进行了对比。结果表明,改进后的算法可以在对红外全息图像中的高斯噪声等环境噪声与散斑噪声进行降噪的同时保留更多细节,是一种更加适用于红外全息图像的降噪方法。 相似文献
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CuO/γ-Al2O3 catalysts were prepared by plasma treatment and conventional impregnation methods. The catalytic combustion of two kinds of volatile organic compounds (VOCs), toluene and benzene, were carried out over these CuO/γ-Al2O3 catalysts. The surface properties of these catalysts were characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The experimental results showed that in catalytic combustion the activity of the CuO/γ-Al2O3 catalyst prepared via plasma was much higher than that of the CuO/γ-Al2O3 catalyst prepared by conventional impregnation method. XRD results showed that an enhanced dispersion had been achieved with the plasma treatment. SEM results indicated that the size became much smaller and the surface became more uniform with the plasma treatment. 相似文献