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Enhanced visible-light photocatalytic oxidation capability of carbon-doped TiO_2 via coupling with fly ash

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Chinese Journal of Catalysis 2018年第12期39卷 1890-1900页

作者： Ning An Yuwei Ma Juming Liu Huiyan Ma Jucai Yang qiancheng zhang Key Lab of Industrial Catalysis of the Inner Mongolia Autonomous Region School of Chemical EngineeringInner Mongolia University of TechnologyHuhhot 010051Inner MongoliaChina School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China School of Energy and Power Engineering Inner Mongolia University of TechnologyHuhhot 010051Inner MongoliaChina

A carbon‐doped TiO2/fly ash support(C‐TiO2/FAS)composite photocatalyst was successfully synthesized through sol impregnation and subsequent *** carbon dopants were derived from the organic species generated during the synthesis of the C‐TiO2/FAS composite.A series of analytical techniques,such as scanning electron microscopy(SEM),attenuated total reflection‐Fourier transform infrared(ATR‐FTIR)spectroscopy,X‐ray photoelectron spectroscopy(XPS),and ultraviolet‐visible diffuse reflectance spectroscopy(UV‐Vis DRS),were used to characterize the properties of the prepared *** results indicated that C‐TiO2 was successfully coated on the FAS *** between C‐TiO2 and FAS resulted in the formation of Si–O–C and Al–O–Ti bonds at their *** formation of Si–O–C and Al–O–Ti bonds gave rise to a positive shift of the valence band edge of C‐TiO2 and enhanced its oxidation capability of photogenerated holes as well as photodegradation efficiency of methyl ***,the C‐TiO2/FAS photocatalyst exhibited favorable reusability and *** work may provide a new route for tuning the electronic band structure of TiO2.

关键词： Fly ash TiO2 Carbon doping Visible‐light photocatalysis Photocatalytic oxidation

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泡沫铝填充金属波纹夹芯梁弯曲破坏模式研究

稀有金属材料与工程 2021年第12期50卷 4365-4371页

作者：闫雷雷张钱城韩宾西北工业大学航空学院陕西西安710072 西安交通大学机械结构强度与振动国家重点实验室陕西西安710049

为了提高金属波纹结构的承载效率,充分发挥泡沫铝在能量吸收方面的优势,设计了泡沫铝填充金属波纹三明治夹芯梁。针对波纹结构各向异性的特点,对其横向和纵向2个方向在三点弯曲载荷作用下的力学响应及破坏模式进行了试验研究。研究表明... 详细信息

为了提高金属波纹结构的承载效率,充分发挥泡沫铝在能量吸收方面的优势,设计了泡沫铝填充金属波纹三明治夹芯梁。针对波纹结构各向异性的特点,对其横向和纵向2个方向在三点弯曲载荷作用下的力学响应及破坏模式进行了试验研究。研究表明,泡沫铝的填充可以有效改变金属波纹夹芯梁的弯曲破坏模式,其弯曲刚度和峰值载荷均得到了大幅提升。和横向弯曲相比,金属波纹夹芯梁在纵向弯曲时具有更强的承载能力,且泡沫铝填充的增强效果更加显著。纵向弯曲时载荷在达到峰值后并不会突然下降而是呈现出很长的平台区,表现出更强的后屈曲承载能力。

关键词：泡沫金属波纹夹芯梁三明治结构三点弯曲力学性能破坏模式

Performance enhancement of sandwich panels with honeycomb–corrugation hybrid core

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Theoretical & Applied Mechanics Letters 2016年第1期6卷 54-59页

作者： Bin Han Wenbin Wang Zhijia zhang qiancheng zhang Feng Jin Tianjian Lu School of Mechanical Engineering Xi'anJiaotong UniversityXi'an 710049China MOE Key Laboratory for Multifunctional Materials and Structures Xi'an Jiaotong UniversityXi'an 710049China State Key Laboratory for Mechanical Structure Strength and Vibration Xi'an Jiaotong UniversityXi'an 710049China

The concept of combining metallic honeycomb with folded thin metallic sheets （corrugation） to construct a novel core type for lightweight sandwich structures is proposed. The honeycomb-corrugation hybrid core is manufactured by filling the interstices of aluminum corrugations with precision-cut trapezoidal aluminum honeycomb blocks, bonded together using epoxy glue. The performance of such hybrid-cored sandwich panels subjected to out-of-plane compression, transverse shear, and three-point bending is investigated, both experimentally and numerically. The strength and energy absorption of the sandwich are dramatically enhanced, compared to those of a sandwich with either empty corrugation or honeycomb core. The enhancement is induced by the beneficial interaction effects of honeycomb blocks and folded panels on improved buckling resistance as well as altered crushing modes at large plastic deformation. The present approach provides an effective method to further improve the mechanical properties of conventional honeycomb-cored sandwich constructions with low relative densities.

关键词： Honeycomb-corrugation Compression Shear Bending Performance enhancement

Novel strengthening methods for ultralightweight sandwich structures with periodic lattice cores

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Science China(Technological Sciences) 2010年第3期53卷 875-877页

作者： LU TianJian 1 &zhang qiancheng 2 1 MOE Key Laboratory for Strength and Vibration,School of Aerospace,Xi’an Jiaotong University,Xi’an 710049,China 2 State Key Laboratory for Mechanical Behavior of Materials,School of Material Science and Engineering,Xi’an Jiaotong University,Xi’an 710049,China 1. MOE Key Laboratory for Strength and Vibration School of Aerospace Xi’an Jiaotong University Xi’an 710049 China2. State Key Laboratory for Mechanical Behavior of Materials School of Material Science and Engineering Xi’an Jiaotong University Xi’an 710049 China

Recent development of ultralightweight lattice-cored sandwiches is reviewed,with focus placed on various novel fabrication methods introduced to strengthen these structures,covering not only research results published... 详细信息

关键词： cellular metals strengthening method fabrication sandwich panels

Improving the visible-light photocatalytic activity of carbon-doped TiO2 with bidentate carboxylate ligands

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Improving the visible-light photocatalytic activity of carbo...

2017全国光催化材料及创新应用学术研讨会

作者： Juming Liu Lu Han Yuwei Ma Ning An Huiyan Ma qiancheng zhang Key Laboratory of Industrial Catalysis of the Inner Mongolia Autonomous Region Inner Mongolia University of Technology

TiO-based photocatalysis as a green chemistry technology has drawn considerable attention due to its extensively potential applications in the fields of organic pollutant degradation and solar energy ***,the wide bandgap of TiO is unfavorable for the high efficient use of solar *** doped TiO has received particular attention and shown significant enhancement in visible-light driven photocatalytic *** can be ascribed to the raised valence band(VB)edge and the narrowed optical bandgap by carbon ***,the major drawback of valence band rising is the loss of oxidizing and degradative capacity of the photogenerated *** we describe the recent progress on tuning the electronic structure of carbon doped TiO by using electron-withdrawing carboxylate *** to the strong covalent binding ability to Ti cations,the carboxylate ligand can act as the linkage between the interstitial carbon and TiO *** bidentate carboxylate ligands can not only strengthen the interaction between the interstitial carbon dopants and TiO lattice to narrow the bandgap and enhance the visible-light absorption,but also lead to the positive shift of the VB edge(pulling the VB edge down)and cause further bandgap narrowing by inducing the band tail states above the VB ***,the visible-light photocatalytic degradative capacity of modified TiO for phenolic contaminants is enhanced,and the recombination of photogenerated charge carriers is inhibited by the electron-withdrawing *** findings of our study may provide new insights for directing the design and synthesis of new TiO-based photocatalysts by controlled bandgap engineering.

关键词： Carbon-doped TiO2 Electron-withdrawing Carboxylate Photocatalysis Phenol degradation

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大视场全天时星敏感器光学系统设计

红外与激光工程 2023年第3期52卷 226-234页

作者：张前程钟胜吕劲松李显成华中科技大学人工智能与自动化学院湖北武汉430074 华中科技大学多谱信息处理技术国家级重点实验室湖北武汉430074 华中光电技术研究所-武汉光电国家研究中心湖北武汉430223

全天时星敏感器作为星敏感器的一个发展分支,在飞机、热气球等近空间载体定姿定位方面有较好的应用前景,是GPS拒止条件下的可用导航手段。大视场全天时星敏感器相较于小视场全天时星敏感器在高精度轻小型化定姿定位方面具有较大的优势,... 详细信息

全天时星敏感器作为星敏感器的一个发展分支,在飞机、热气球等近空间载体定姿定位方面有较好的应用前景,是GPS拒止条件下的可用导航手段。大视场全天时星敏感器相较于小视场全天时星敏感器在高精度轻小型化定姿定位方面具有较大的优势,针对近空间高度大视场全天时测星对光学系统的需求,对光学系统工作波长的选取进行了分析,利用消色差和消热差设计,实现了一种能够适应高低温环境的大视场、大相对孔径的透射式光学系统,并对像质进行了分析评价。系统工作波长为0.9~1.7μm,F/#为1.4,焦距为70 mm,视场为18°,结构总长为105 mm。试验结果表明,该光学系统具有良好的像质,能够满足大视场星敏感器白天测星要求。

关键词：光学设计星敏感器消热差短波红外

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Analytical design of effective thermal conductivity for fluid-saturated prismatic cellular metal honeycombs

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Theoretical & Applied Mechanics Letters 2016年第2期6卷 69-75页

作者： Wenbin Wang Xiaohu Yang Bin Han qiancheng zhang Xiangfei Wang Tianjian Lu MOE Key Laboratory for Multifunctional Materials and Structures Xi'an Jiaotong UniversityXi'an 710049China Department of Building Environment and Energy Engineering Xi'an Jiaotong University.Xi'an 710049China School of Mechanical Engineering Xi'an fiaotong UniversityXi'an 710049.China State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an jiaotong UniversityXi'an 710049China

A comparative optimal design of fluid-saturated prismatic cellular metal honeycombs （PCMHs） having different cell shapes is presented for thermal management applications. Based on the periodic topology of each PCMH, a unit cell （UC） for thermal transport analysis was selected to calculate its effective thermal conductivity. Without introducing any empirical coefficient, we modified and extended the analytical model of parallel-series thermal-electric network to a wider porosity range （0.7 ~ 0.98） by considering the effects of two-dimensional local heat conduction in solid ligaments inside each UC. Good agreement was achieved between analytical predictions and numerical simulations based on the method of finite volume. The concept of ligament heat conduction efficiency （LTCE） was proposed to physically explain the mechanisms underlying the effects of ligament configuration on effective thermal conductivity （ETC）. Based upon the proposed theory, a construct strategy was developed for designing the ETC by altering the equivalent interaction angle with the direction of heat flow： relatively small average interaction angle for thermal conduction and relatively large one for thermal insulation.

关键词： Effective thermal conductivityPrismatic cellular metal honeycombLigament heat conduction efficiencyAnalytical designEquivalent interaction angle

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信贷期限结构与实体经济资本回报率

国际金融研究 2021年第6期 23-33页

作者：张前程范从来安徽大学经济学院南京大学长江三角洲经济社会发展研究中心

本文从理论和实证层面考察金融体系信贷期限结构对实体经济资本回报率的影响,并探究其中的机制路径。结果表明,信贷期限结构对实体经济资本回报率的影响呈倒U形特征。样本期内信贷期限结构对不同所有制类型资本回报率的影响存在差异,"... 详细信息

本文从理论和实证层面考察金融体系信贷期限结构对实体经济资本回报率的影响,并探究其中的机制路径。结果表明,信贷期限结构对实体经济资本回报率的影响呈倒U形特征。样本期内信贷期限结构对不同所有制类型资本回报率的影响存在差异,"三期叠加"冲击恶化了信贷期限结构对实体经济资本回报率的影响。信贷期限结构通过包含技术进步推动效应和基础设施外溢效应的提升机制对资本回报率产生正向作用,通过包含利息成本侵蚀效应和房地产虹吸效应的阻碍机制对资本回报率产生负向作用。然而,"双机制四效应"对不同信贷期限结构有着异质性表现,叠加后的相互抵消效应使金融体系信贷期限结构与实体经济资本回报率之间呈倒U形关系。本文的研究结论为增强金融服务实体经济能力及深化金融体制改革提供有价值的参考。

关键词：信贷期限结构实体经济资本回报率

基于实验模态分析的点阵夹层结构动态性能预测

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固体力学学报 2008年第4期29卷 373-378页

作者：李斌潮张钱城卢天健西安交通大学强度与振动教育部重点实验室西安710049 西安交通大学材料科学与工程系西安710049

引入均一化等效理论,对金字塔型结构芯体夹层材料的芯体弹性常数进行均一化等效处理,并将其用于研究该夹层材料结构的动态性能.同时采用三维(3D)离散有限元模型计算了结构的动态性能.为验证了理论预测的正确性,设计并制备了金字塔点阵... 详细信息

引入均一化等效理论,对金字塔型结构芯体夹层材料的芯体弹性常数进行均一化等效处理,并将其用于研究该夹层材料结构的动态性能.同时采用三维(3D)离散有限元模型计算了结构的动态性能.为验证了理论预测的正确性,设计并制备了金字塔点阵悬臂梁,进行了实验模态分析,将实验结果与理论计算的各阶自振频率进行了比较.结果表明:该模型对低阶自振频率的计算结果与实验结果、3D离散有限元模型计算结果吻合得都比较好,一阶自振频率误差不到5%,其它误差在10%左右.

关键词：点阵材料均一化有限元夹层板模态分析