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Anatase TiO2with exposed{001}facets has been deepgoingly studied for optimizing its photocatalytic activity.In this study,we synthesized N-doped TiO2 nanocrystals with exposed{001}facets by sol–gel method and solvothermal method,respectively.The physical and chemical properties of as-synthesized samples,such as morphology,crystal phase,surface elements composition,porous structure,specific surface area,and optical response,were characterized in detail.The photocatalytic performances of all samples were evaluated by photocatalytic decoloration of methylene blue under visible-light irradiation(k[420 nm).The results showed that the as-prepared samples present high visible-light photocatalytic performances,which can be ascribed to the excellent crystallization,the enhancement of absorbance in the visible-light region,and the strong adsorption performance,and calcination treatment is helpful to further improve the visible-light photocatalytic performance of N-doped TiO2 nanocrystals with exposed{001}facets. 相似文献
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电力输电线路高塔驱鸟系统设计 总被引:1,自引:0,他引:1
针对鸟害容易引起电力输电线路事故的问题,设计了一个红外驱鸟报警系统。系统采用被动式热释电红外传感器作为检测部件,进行非接触式远距离检测,并将检测到的微弱电信号转换输出,经被动式热释电红外传感信号处理器BISS0001,进行运算放大、滤波、功率放大,利用所得信号触发报警电路,使鸟受到惊吓飞离杆塔,从而保护输电线路免受鸟害威胁。分析表明,系统具有良好且环保的驱鸟效果。 相似文献
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核盘菌多糖是由核盘菌(Sclerotinia sclerotiorum)通过深层发酵产生的一种胞外多糖。本文通过单因子试验和正交试验对其摇瓶发酵条件进行了优选,使SSG的产率达到12.03g/L,碳源转化率达40.1%;纸层析和红外光谱分析表明,SSG是一种由β-键连接的葡聚糖,其水溶液具有良好的增粘性和假塑性。 相似文献
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This paper focuses on a typical automotive piston material to characterize its fractographic appearance after tensile rupture. The fracture of this heavily alloyed Al—Si alloy takes place in a brittle manner.The consecutive eutectic zone is found to break by debonding of Si platelets from the Al matrix or by fracturing of Si platelets.The various intermetallic particles break up complicatedly under the stress field of the propagating crack.The fracture tends to pass through or approach to the boundary be... 相似文献
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A new random hierarchical model to describe the neighborhood properties of Kaixin001 network is developed in this paper.The degree distribution of this network model follows P(k) ∝ k-γ with γ=1.It means the network model has a powerlaw distribution.Through calculating the clustering coefficients and average path length (APL),the result reflects that the model has the properties of high clustering coefficients and low APL. 相似文献
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席晓青 《海军工程大学学报(综合版)》2011,8(4):79-84
视角作为构建语篇的一种意义资源,涉及叙述者的定位、聚焦、心理、观念等,是理解语篇的重要因素之一,从更高层面制约语篇的衔接与连贯。文中在语篇分析评估循环模式下,讨论视角选择、视角表现、话题与视角;探寻语篇视角中的时间切面、空间切面、心理切面和观念切面如何在语气和情态上得到体现,实现对言语资源的更合理的理解和评价。视角切面研究有助于挖掘视角在语篇人际意义方面的贡献,从而为语篇整体意义研究提供新的视野。 相似文献
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以水热法成功制备了(110)面暴露的高活性多孔单晶CeO2空壳球催化剂样品,研究了其形成过程并提出了相应的形成机理.通过X射线衍射、透射电镜及低温氮气吸附/脱附等温线对催化剂结构进行了详细的表征,结果表明:该材料具有多孔结构以及较高的比表面积(259 m2/g).该多孔单晶CeO2催化剂在CO氧化转化中显示了较好的催化性能,其催化活性远高于商业化CeO2,这主要归结于其特殊的(110)高能面的暴露以及多孔单晶结构. 相似文献