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A large specific surface area perovskite-type mixed oxide PbTiO3 supported cupric oxide was synthesized as a catalyst for NO decomposition and characterized by techniques such as XPS, XRD, H2-TPR before and after NO decomposition reactions. The catalytic properties were tested with a fix-bed micro-reactor. The results showed that the PbTiO3 was inactive for the reactions, but 1wt % Cu/PbTiO3 catalyst gave fairly good activities for NO decomposition at temperature as low as 473 K. Copper species were found well-dispersed but weakly interacted with the support before NO decomposition, and the NO decomposition caused significant change in the environment of the copper species, which became Cu(Ⅰ) and most probably incorporated into surface crystal lattice of the nano-sized PbTiO3. In NO reaction, a large amount of oxygen atoms from the decomposition of NO penetrated into the nano-sized PbTiO3 support and caused small expansion of crystal lattice. The transport of oxygen between the copper species and the catalyst support may be helpful to speed up the kinetic regeneration of active metal sites from oxygen occupancy and resulted in good catalytic performance. 相似文献
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用同步辐射X-荧光定量测定电泳分离后蛋白条带内的微量元素 总被引:2,自引:0,他引:2
建立了同步辐射X荧-光(SRXRF)定量测定生物样品等电聚焦(IEF)分离后蛋白条带内的微量元素Fe、Cu和Zn的方法。用薄层聚丙烯酰胺凝胶分离人血红蛋白后,用SRXRF测定了各亚型条带内的金属含量,用加一定量金属的含蛋白聚丙烯酰胺凝胶做SRXRF定量测定蛋白条带内微量元素Fe、Cu和Zn的定量标准,校准曲线线性回归系数r在0~8μg/g范围内均大于0.99;检出限分别为2.43、1.12和0.96μg/g;测定蛋白条带内Fe和Zn的回收率分别为90.4%和115.7%。该联用技术可用于生物样品中微量元素的化学形态分析,同时给出蛋白质的微量元素组成和等电点等信息。 相似文献
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构造了一类基于对数函数的凹凸组合(凹函数和凸函数乘积形式)的洛伦兹曲线模型,并针对19个国家的收入分配数据进行数值实验.实验结果表明,该类模型具有较好的拟合效果. 相似文献
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基于透射边界条件的高阶离散型角点条件 总被引:2,自引:0,他引:2
对波动方程的数值模拟中,在有限区域建立吸收边界条件,其中对区域角点的处理是一个很重要的问题.随着吸收边界条件阶数的提高,与之匹配的角点条件也越难建立.MTF是一种离散型吸收边界条件.在此,对于二维问题,基于MTF建立离散型高阶角点条件,对计算区域角点处理时,在区域对角线方向上建立N阶MTF公式.问题也可推广到三维.数值结果证实了我们的猜测. 相似文献
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对不同厚度聚四氟乙烯板(简称FIFE)和LC4铝合金板,用搅拌摩擦焊(简称FSW)的方法来实现复合材料的焊接,这是一个新的探索。本试验中研究了FSW的工艺参数:焊接行走速度,搅拌头材料与形状,搅拌头旋转速度和倾斜角度等,用X衍射仪、图像分析仪等对试样的焊接区进行分析。结果显示:搅拌摩擦焊的方法可使聚四氟乙烯板材、铝合金LC4板材焊接。 相似文献
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