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Journal of Energy Chemistry 2022年第7期31卷 388-393,I0011页

作者： Xianwen Zhang Zheng Li Bin Zeng Can Li Hongxian Han State Key Laboratory of Catalysis and Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

Understanding the processes of charge generation, transfer and capture is important for the design and synthesis of efficient photocatalysts. In this work, light-induced charge separation and effect of O_(2) on electron transfer processes in SrTiO_(3) were investigated by electron paramagnetic resonance(EPR). It was found that photoinduced electron transfer from O_(2)- to Ti^(4+) produced Ti^(3+) and O- redox radical pairs under vacuum condition. Under oxygen atmosphere, however, surface bound superoxide radicals O_(2)-were formed by electron reduction of adsorbed oxygen at initial photoirradiation stage, and quenched by the reverse electron transfer to Ti^(4+) upon further photoirradiation. Formation of long-lived charge separation associated [Ti^(3+)---O-] species and the reversibility of surface bound superoxide radicals mediating the processes of photogenerated electrons may be accountable for the high activity of SrTiO_(3) in photocatalytic water splitting reaction.

关键词： Photocatalyst Electron paramagnetic resonance Charge separation Superoxide radicals

Photocatalysis in solar fuel production

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National Science Review 2015年第2期2卷 145-147页

作者： Hongxian Han Can Li State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences and Dalian National Laboratory for Clean Energy

With the increasing concerns on energy and environmental problems caused by the combustion of fossil fuels,solar energy becomes vitally important because it is the only viable renewable energy source that can replace ... 详细信息

关键词： PSP

A Novel Sr_2CuInO_3S p-type semiconductor photocatalyst for hydrogen production under visible light irradiation

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Journal of Energy Chemistry 2014年第4期23卷 420-426页

作者： Yushuai Jia Jingxiu Yang Dan Zhao Hongxian Han Can Li State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian National Laboratory for Clean Energy

A novel Sr2CulnO3S oxysulfide p-type semiconductor photocatalyst has been prepared by solid state reaction method and it exhibits intriguing visible light absorption properties with a bandgap of 2.3 eV. The p-type semiconductor character of the synthesized Sr2CuInO3 S was confirmed by Hall efficient measurement and Mott-Schottky plot analysis. First-principles density functional theory calculations （DFT） and electrochem ical measurements were performed to elucidate the electronic structure and the energy band locations. It was found that the as-synthesized Sr2CuInO3S photocatalyst has appreciate conduction and valence band positions for hydrogen and oxygen evolution, respectively. Photocat alytic hydrogen production experiments under a visible light irradiation （A〉420 nm） were carried out by loading different metal and metal-like cocatalysts on Sr2CuInO3S and Rh was found to be the best one among the tested ones.

关键词： hydrogen production photocatalyst p-type semiconductor Sr2CuIn03S oxysulfide visible light cocatalyst

p-Type CaFe_2O_4 semiconductor nanorods controllably synthesized by molten salt method

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Journal of Energy Chemistry 2016年第3期25卷 381-386页

作者： Xin Liu Junzhe Jiang Yushuai Jia Ailing Jin Xiangshu Chen Fei Zhang Hongxian Han Jiangxi Inorganic Membrane Materials Engineering Research Centre College of Chemistry and Chemical Engineering Jiangxi Normal University State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian National Laboratory for Clean Energy

Pure phase, regular shape and well crystallized nanorods of p-type semiconductor CaFeOhave been fabricated for the first time by a facile molten salt assisted method, as confirmed by XRD, TEM, SEM and HRTEM. UV-vis diffuse reflectance spectra and Mott–Schottky plots show that the band structure of the CaFeOnanorods is narrower than that of the CaFeOnanoparticles synthesized by conventional method. The enhancement of the visible-light absorption is due to narrowness of the band gap in CaFeOnanorods. The appropriate ratio between the molten salt and the CaFeOprecursors plays an important role in inhibiting the growth of the crystals along the(201) plane to give the desired nanorod morphology. This work not only demonstrates that highly pure p-type CaFeOsemiconductor with tunable band structure and morphology could be obtained using the molten salt strategy, but also affirms that the bandgap of a semiconductor may be tunable by monitoring the growth of a particular crystal plane.Furthermore, the facile eutectic molten salt method developed in this work may be further extended to fabricate some other semiconductor nanomaterials with a diversity of morphologies.

关键词： p-Type semiconductor CaFe_2O_4 nanorods Molten salt Crystal plane Visible-light absorption

Preface to the Special Issue of Photocatalysis for Solar Fuels

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Chinese Journal of Catalysis 2018年第3期39卷 367-368页

作者：韩洪宪刘岗 State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of Sciences School of Future Technology University of Chinese Academy of Sciences Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences College of Materials Science and Engineering University of Science and Technology of China

As natural photosynthesis does, direct conversion of solar energy into the storable form of chemical energy is an intriguing technology for solar energy utilization. Due to increasing concerns of energy and environmental problems caused by the consumption of fossil fuels, production of chemical solar fuels (such as hydrogen, methanol or methane,etc) by artificial photosynthesis, namely photocatalytic splitting of water or reduction of CO2, has been a hot research topic in recent years.

关键词： As natural photosynthesis does, direct conversion of solar energy

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中国写作理论元范畴“辞”论纲

长江学术 2024年第2期 55-66页

作者：戴红贤武汉大学文学院湖北武汉430072

“辞”是“司”的后起分化字。西周青铜铭文中“辞”与法律诉讼有关,本义为“讼辞”。东周“辞”引申出普通言辞的意义,孔子提出“修辞”概念,诸子共同建构了修辞伦理、修辞技艺和文体三位一体的修辞学说。修辞学术以语言为中心探索了... 详细信息

“辞”是“司”的后起分化字。西周青铜铭文中“辞”与法律诉讼有关,本义为“讼辞”。东周“辞”引申出普通言辞的意义,孔子提出“修辞”概念,诸子共同建构了修辞伦理、修辞技艺和文体三位一体的修辞学说。修辞学术以语言为中心探索了怎样思考、如何表达的问题,具有很强的工具性。“辞”成为一个跨界语言学、逻辑学、修辞学、文体学的重要范畴,被提升到理论层面予以反思和研究。这是中国写作理论元范畴“关键的一跳”。秦汉以来“言文分离”,随着诗文书写日益发展,表意单位为篇章且基于书面文辞的“辞章”概念产生。先秦修辞学演化为汉魏六朝辞章学,后者追求作品的辞藻、辞趣,偏向语言风格旨趣,窄化了写作学范围。如何赓续传统,继往开来,推进全球视域下21世纪中国写作学术的繁荣与发展,由“辞”进入,当能另辟蹊径。

关键词：辞讼辞修辞辞章文章写作学

基于增强熵权峭度图的滚动轴承最优频带解调的故障诊断

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振动与冲击 2019年第17期38卷 24-31,50页

作者：李红贤汤宝平韩延邓蕾重庆大学机械传动国家重点实验室重庆400030 中国航空工业集团公司中国飞机强度研究所西安710065

针对采用峭度指标选取滚动轴承最优共振解调频带时存在精确性差和易受随机冲击干扰的不足,提出了基于增强熵权峭度图的滚动轴承最优频带解调的故障诊断。首先,选取峭度指标、变异系数、裕度指标和平滑因子等评价指标分别从不同角度表征... 详细信息

针对采用峭度指标选取滚动轴承最优共振解调频带时存在精确性差和易受随机冲击干扰的不足,提出了基于增强熵权峭度图的滚动轴承最优频带解调的故障诊断。首先,选取峭度指标、变异系数、裕度指标和平滑因子等评价指标分别从不同角度表征故障轴承瞬态冲击特征,增强在实际监测的运行环境中单指标抗干扰鲁棒性差的缺陷;其次,采用熵权法对多个评价指标计算综合属性客观权重,为了增强轴承瞬态冲击表征和抑制其它信息干扰,对评价指标值进行增强处理并融合形成新评价指标,以精确选取共振解调中心和带宽;最后,采用1/3-二叉树策略生成的增强熵权峭度图自适应识别故障轴承最优解调频带。通过实测信号和仿真信号测试分析,并与快速峭度图在不同干扰下对比表明,该方法可以更为精准的识别轴承共振频带及具有更高的鲁棒性。

关键词：滚动轴承峭度图熵权法最优频带故障诊断

迭代广义解调齿轮信号分离的变转速滚动轴承故障诊断

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振动与冲击 2018年第23期37卷 38-44页

作者：李红贤汤宝平韩延邓蕾重庆大学机械传动国家重点实验室重庆400030

变转速工作模式下齿轮啮合会掩盖故障轴承冲击特征,使得轴承故障特征信息微弱,针对变转速工作模式下齿轮啮合对轴承信号干扰的问题,提出了迭代广义解调齿轮信号分离的变转速滚动轴承的故障诊断方法。首先采用峰值搜索算法从包络时频谱... 详细信息

变转速工作模式下齿轮啮合会掩盖故障轴承冲击特征,使得轴承故障特征信息微弱,针对变转速工作模式下齿轮啮合对轴承信号干扰的问题,提出了迭代广义解调齿轮信号分离的变转速滚动轴承的故障诊断方法。首先采用峰值搜索算法从包络时频谱中提取峰值啮合倍频(Instantaneous Dominant Meshing Multiply,IDMM),通过IDMM趋势线构造各广义解调函数的相位函数;其次利用迭代广义解调算法(Iterative Generalized Demodulation,IGD)分离出齿轮啮合频率及倍频信号,对剩余信号采用谱峭度算法确定由故障轴承引起的高频共振滤波参数并进行带通滤波;最后,以提取的IDMM趋势线作为轴承转频,对滤波结果进行角域重采样,根据阶次谱对滚动轴承运行状态予以判断。仿真信号和实测信号的处理结果证明该方法在无转速计设备的情况下能有效的实现变转速滚动轴承的故障诊断。

关键词：变转速滚动轴承齿轮干扰迭代广义解调故障诊断

基于ICA包络增强MEMD的滚动轴承故障诊断

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航空动力学报 2021年第2期36卷 405-412页

作者：李红贤韩延吴敬涛汤宝平中国航空工业集团有限公司中国飞机强度研究所西安710065 重庆大学机械传动国家重点实验室重庆400030

针对多元经验模态分解(MEMD)存在模态混叠、带内噪声干扰导致轴承故障特征信息微弱难提取问题,提出了基于独立分量分析(ICA)包络增强MEMD的滚动轴承故障诊断。采用MEMD对多通道信号进行自适应分解,依据峭度和相关系数选取包含故障信息... 详细信息

针对多元经验模态分解(MEMD)存在模态混叠、带内噪声干扰导致轴承故障特征信息微弱难提取问题,提出了基于独立分量分析(ICA)包络增强MEMD的滚动轴承故障诊断。采用MEMD对多通道信号进行自适应分解,依据峭度和相关系数选取包含故障信息的本征模态函数(IMF);对所选取IMF分量的包络信号进行ICA分析,抑制模态混叠和削弱带内噪声;选取峭度最大的独立分量包络进行频谱分析,判断滚动轴承的运行状况。实测信号结果表明:ICA包络增强MEMD后包络谱中可以清楚地看到前6阶故障频率,故障特征频率误差小于1 Hz,其他方法只能看到2~3阶,且干扰频率成分较多。

关键词：多元经验模态分解独立分量分析滚动轴承特征信息微弱故障诊断

Haze Control by Industrialization:A Win-win Mode of Ecological Civilization and Economic Development

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Asian Agricultural Research 2017年第2期9卷 66-71页

作者： Yan han Qingyu CHAI Lei WANG Yunlong YAO Yunna JIA Jiahui SHAO hongxian YU Fangying CHAI Shunde Entry-Exit Inspection and Quarantine Bureau Northeast Forestry University Heilongjiang University of Science and Technology Department of Water Resources of Heilongjiang Province

Haze control is a difficult and arduous battle,and it is a major decision concerning the people's livelihood and national ecological civilization construction.Taking Heilongjiang Province as an example,this paper introduced a new idea for haze control.Haze in Heilongjiang Province was mainly resulted from straw burning.Market-oriented,large-scale,and industrialized haze control relying on science and technology is new opportunity and challenge for realizing ecological civilization and revitalizing the economy of Heilongjiang Province.

关键词： Haze Control Industrialization