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Effects of SO2 on the low temperature selective catalytic reduction of NO by NH3 over CeO2-V2O5-WO3/TiO2 catalysts

Frontiers of Environmental Science & Engineering 2017年第4期11卷 153-159页

作者： Quanming liang Jian Li Hong He wenjun liang Tiejun Zhang Xing Fan Key Laboratory of Beijing on Regional Air Pollution Control Beijing University of Technology Beijing 100124 China Beijing Key Laboratory for Green Catalysis and Separation Beijing University of Technology Beijing 100124 China

The CeO2-V2O5-WO3/TiO2 （CeO2-VWT） catalysts were prepared by one-step and two-step impregnation methods. The effects of different loading of CeO2 and different preparation methods on De-NOx activity of catalysts had been investigated. CeO2 helped to improve the De-NOx activity and sulfur resistance. The optimal loading of CeO2 was 3% with the De-NOx efficiency reached 89.9% at 140℃. The results showed that the De-NOx activity of 3% CeO2-VWT catalysts by one-step method was the same as two-step method basically and reached the level of industrial applications, the N2 selectivity of catalysts was more than 99.2% between 110℃ and 320℃. In addition, CeO2 promoted the oxidation of NO to NO2, which adsorbed on the Lewis acid site （V5＋-O） to form V5＋-NO3 and inspired the fast SCR reaction. Not only the thermal stability but also the De-NOx activity of catalysts decreased with excess CeO2 competed with V2O5. Characterizations of catalysts were carried out by XRF, BET, XRD, TG and FT-IR. BET showed that the specific surface area of catalysts decreased with the loading of CeO2 increased, the active components content and specific surface area of catalysts decreased slightly after entering SO2. Ammonium sulfate species were formed in poisoned catalyst which had been investigated by XRF, BET, TG and FT-IR. The largest loss rate of weight fraction was 0.024%.℃-1 at 380℃ 390℃, which was in accordance with the decomposition temperature of NH4HSO4 and （NH4）2SO4,

关键词： Low temperature SCR De-NOx activity Sulfur resistance Ammonium sulfate

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Transformation of single drop breakup from binary to ternary and multiple in turbulent jet flows

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Chinese Journal of Chemical Engineering 2021年第6期34卷 32-39页

作者： wenjun liang Dengfei Wang Meijuan Qian Ziqi Cai Zhipeng Li Zhengming Gao Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Chemical Resource Engineering School of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Daqing Petrochemical Research Center Petrochemical Research InstituteChina National Petroleum CorporationDaqing 163714China

By releasing liquid drops in turbulent jet flows,we investigated the transformation of single drop breakup from binary to ternary and *** oil and deionized water were the dispersed phase and continuous phase,*** probability of binary,ternary,and multiple breakup of oil drops in jet flows is a function of the jet Reynolds *** address the underlying mechanisms of this transformation of drop breakup,we performed two-dimensional particle image velocimetry(PIV)experiments of single-phase jet *** the combination of drop breakup phenomenon and two-dimensional PIV results in a single-phase flow field,these transformation conditions can be estimated:the capillary number ranges from 0.17 to 0.27,and the Weber number ranges from 55 to 111.

关键词： Drop Multiple breakup Jet flows PIV Breakup mechanism

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The anisotropy of suprathermal electrons in the Martian ionosphere

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Earth and Planetary Physics 2024年第3期8卷 459-471页

作者： YuTian Cao Jun Cui XiaoShu Wu wenjun liang RuiQi Fu HaoYu Lu Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai 519082China Key Laboratory of Geospace Environment University of Science&Technology of ChinaChinese Academy of SciencesHefei 230026China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230026China School of Space and Environment Beihang UniversityBeijing 102206China

Suprathermal electrons are an important population of the Martian ionosphere, either produced by photoionization of atmospheric neutrals or supplied from the Solar Wind (SW). This study is dedicated to an in-depth investigation of the pitch angle distribution of suprathermal electrons at two representative energies, 19−55 eV and 124−356 eV, using the extensive measurements made by the Solar Wind Electron Analyzer on board the Mars Atmosphere and Volatile Evolution. Throughout the study, we focus on the overall degree of anisotropy, defined as the standard deviation of suprathermal electron intensity among different directions which is normalized by the mean omni-directional intensity. The available data reveal the following characteristics: (1) In general, low energy electrons are more isotropic than high energy electrons, and dayside electrons are more isotropic than nightside electrons;(2) On the dayside, the anisotropy increases with increasing altitude at low energies but remains roughly constant at high energies, whereas on the nightside, the anisotropy decreases with increasing altitude at all energies;(3) Electrons tend to be more isotropic in strongly magnetized regions than in weakly magnetized regions, especially on the nightside. These observations indicate that the anisotropy is a useful diagnostic of suprathermal electron transport, for which the conversion between the parallel and perpendicular momenta as required by the conservation of the first adiabatic invariant, along with the atmospheric absorption at low altitudes, are two crucial factors modulating the observed variation of the anisotropy. Our analysis also highlights the different roles on the observed anisotropy exerted by suprathermal electrons of different origins.

关键词： Mars ionosphere suprathermal electron pitch angle distribution

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Use of rare earth elements in single-atom site catalysis:A critical review——Commemorating the 100th anniversary of the birth of Academician Guangxian Xu

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Journal of Rare Earths 2021年第3期39卷 233-242,I0001页

作者： Ningqiang Zhang Han Yan Lingcong Li Rui Wu Liyun Song Guizhen Zhang wenjun liang Hong He Key Laboratory of Beijing on Regional Air Pollution Control and Beijing Key Laboratory for Green Catalysis and Separation Beijing University of TechnologyBeijing 100124China Department of Chemistry Tsinghua UniversityBeijing 100084China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing 100081China

Rare earth metals are strategic resources with potential applications in optics,metallurgy and *** recent years,single-atom site catalysts(SASCs) have attracted increasing attention owing to their 100%atom efficiency and unique catalytic *** the past decade,rare earth elements,including rare earth metals and their oxides,have shown great potential in ***,systematic analyses of data are still *** this mini-review,the use of rare earth metals and their oxides in SASCs was summarized and the results are discussed.A particular focus was paid to the synthetic strategies,characterization of rare earth-containing SASCs,and applications as catalysis supports,promoters and active *** issues faced by rare-earth metals and their oxides in SASCs,as well as future prospects were also provided.

关键词： Rare earth catalysis Single-atom site catalysis Synthetic strategies Characterization Applications

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Global trends of tropopause folds in recent decades

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Atmospheric and Oceanic Science Letters 2024年第3期17卷 14-19页

作者： Yufeng Lin Wenshou Tian Haiyang Xue Jiali Luo Jiankai Zhang Hongying Tian wenjun liang College of Atmospheric Sciences Lanzhou UniversityLanzhouChina School of Atmospheric Sciences Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Sun Yat-sen UniversityZhuhaiChina

对流层顶折卷是平流层-对流层物质交换的主要机制.本研究采用三维标记方法,利用1979-2020年间的ERA5再分析数据,分析了对流层顶折卷的时空变化特征及机理.研究结果表明,全球对流层顶折卷的多年变化趋势存在明显的季节性和区域性差异.总... 详细信息

对流层顶折卷是平流层-对流层物质交换的主要机制.本研究采用三维标记方法,利用1979-2020年间的ERA5再分析数据,分析了对流层顶折卷的时空变化特征及机理.研究结果表明,全球对流层顶折卷的多年变化趋势存在明显的季节性和区域性差异.总体上,对流层顶折卷呈增加趋势,其中北半球的春季,夏季和冬季,对流层顶折卷主要沿副热带急流区呈现明显增加的趋势.进一步分析表明,对流层顶折卷发生频率的增加与大气斜压性增大导致的锋生增强有关,而经向位温梯度的增大使得次级环流增强,也可能促进了对流层顶折卷活动的增多.

关键词：对流层顶折卷趋势锋生大气斜压性

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Degradation of chlorobenzene by non-thermal plasma coupled with catalyst:influence of catalyst,interaction between plasma and catalyst

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Plasma Science and Technology 2023年第5期25卷 170-183页

作者：石秀娟梁文俊尹国彬刘佳 Key Laboratory of Beijing on Regional Air Pollution Control Beijing University of TechnologyBeijing 100124People’s Republic of China State Environmental Protection Key Laboratory of Odor Pollution Control Tianjin Academy of Ecoenvironmental SciencesTianjin 300191People’s Republic of China

Non-thermal plasma(NTP)is considered to be a promising technology for the removal of volatile organic compounds;however,its application is limited by low CO_(2) selectivity and undesirable *** overcome these issues,this paper discusses the degradation of chlorobenzene(CB)in systems of NTP coupled with catalysts,and the influence of catalyst locations in the NTP was *** addition,the interaction between plasma and catalyst was also *** results indicated that the degradability of CB was remarkably improved through the combination of NTP with catalysts,and the formation of ozone was effectively *** degradation efficiency increased from 33.9%to 79.6%at 14 kV in the NTPcatalytic system,while the ozone concentration decreased from 437 to 237 mg m^(-3),and the degradation efficiency of in plasma catalysis(IPC)systems was superior to that of the post plasma catalysis system,while the inhibition ability of ozone exhibited an opposing *** the IPC system,the degradation efficiency was 87.7%at 14 k V,while the ozone concentration was151 mg m^(-3).Besides,the plasma did not destroy the pore structure and crystal structure of the catalyst,but affected the surface morphology and redox performance of the ***,NTP coupled catalytic system could improve the degradation performance of ***,the plasma discharge characteristics played a major role in the NTP synergistic catalytic degradation of ***,based on the experiment analysis results,the general reaction mechanism of CB degradation in an IPC reaction system was proposed.

关键词： non-thermal plasma chlorobenzene catalysts ozone decomposition mechanism

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Effect of V2O5 Supported on the Sulfated TiO2 for Low-temperature SCR of NO by NH3

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环境科学前沿（中英文版） 2014年第2期3卷 6-12页

作者： Ludi Zhang Jian Li Hong He wenjun liang Quanming liang Key Laboratory of Beijing on Regional Air Pollution Control Beijing university of Technology Beijing 100124 China

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Impacts of the atmospheric apparent heat source over the Tibetan Plateau on summertime ozone vertical distributions over Lhasa

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Atmospheric and Oceanic Science Letters 2021年第3期14卷 66-71页

作者： wenjun liang Zhen Yang Jiali Luo Hongying Tian Zhixuan Bai Dan Li Qian Li Jinqiang Zhang Haoyue Wang Bian Ba Yang Yang Key Laboratory of Semi-Arid Climate Change and College of Atmospheric Sciences Lanzhou UniversityLanzhouChina Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Department of Atmospheric Science Yunnan UniversityKunmingChina Atmospheric Observation Centre of Lhasa Meteorological Bureau LhasaChina Institute of Arid meteorology China Meteorological AdministrationLanzhouChina

The Tibetan Plateau(TP)is an area sensitive to climate change,where the ozone distribution affects the atmospheric environment of the TP and its surrounding *** relatively low total column ozone over the TP in boreal summer and its spatiotemporal variations have received extensive *** this study,five-year balloon-borne measurements of ozone over Lhasa in boreal summer are used to investigate the influences of the apparent heat source(Q1)on the ozone vertical structure over the *** mechanisms for the above processes are also *** results show that the tropospheric ozone mixing ratio over Lhasa decreases when the total atmospheric Q1 in the troposphere over the TP is relatively *** ascending motions are accompanied by enhanced Q1 over the main TP ***,the tropospheric ozone mixing ratio over Lhasa decreases when Q1 is higher in summer,which is attributed to the upward transport of the ozone-poor surface air.

关键词： Ozone Tibetan Plateau Atmospheric apparent heat source Ascending motion

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Cr负载V2O5-WO3/TiO2催化剂的低温NH3-SCR脱硝活性

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高等学校化学学报 2019年第7期40卷 1447-1455页

作者：李春晓李坚梁文俊梁全明北京工业大学区域大气复合污染防治北京市重点实验室

采用浸渍法制备了一系列不同Cr负载量的CrOx-V2O5-WO3/TiO2催化剂,研究了Cr改性对该催化剂脱硝活性及抗硫性能的影响.结果表明,Cr的引入使V2O5-WO3/TiO2催化剂的低温NOx去除效果和抗硫性能显著提升.Cr的负载量为3%(以Cr2O3计算质量分数)... 详细信息

采用浸渍法制备了一系列不同Cr负载量的CrOx-V2O5-WO3/TiO2催化剂,研究了Cr改性对该催化剂脱硝活性及抗硫性能的影响.结果表明,Cr的引入使V2O5-WO3/TiO2催化剂的低温NOx去除效果和抗硫性能显著提升.Cr的负载量为3%(以Cr2O3计算质量分数)时,催化剂具有最佳的低温脱硝活性和N2选择性.结构表征结果表明,改性催化剂中Cr元素主要以Cr^3+形式存在,Cr的引入使催化剂的氧化性能明显提升,并使表面弱酸位点、强酸位点和催化剂表面吸附氧数量增多.XPS分析结果表明,Cr能使催化剂中V^5+/V^4+比例降低,促进催化剂中自由电子的迁移.In situ DRIFTs表征结果显示,Cr的引入能促进NO与吸附在Bronsted酸位点上的NH3在低温条件下反应,从而使催化剂具有更好的低温脱硝活性.UV-Vis光谱分析结果表明,CrOx负载量提高会显著增加高价态Cr的烧结聚集.同时,提出了一种选择性催化还原(SCR)反应中Cr-V协同催化的机理.

关键词：选择性催化还原 Cr改性低温脱硝活性

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中国画的民族性在中国风首饰设计中的应用

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宝石和宝石学杂志（中英文） 2022年第4期24卷 68-75页

作者：梁文思梁文峻广州城市理工学院广东广州510800

通过中国画的民族性在中国风首饰设计上的应用与实践,探索中国风首饰设计的发展思路,在新时代的背景下建立民族自信,使民族文化传承更具生命力和生活性。中国画在传统美学思想的影响下对于造型、色彩、个性和审美情趣有独特的理解与表现... 详细信息

通过中国画的民族性在中国风首饰设计上的应用与实践,探索中国风首饰设计的发展思路,在新时代的背景下建立民族自信,使民族文化传承更具生命力和生活性。中国画在传统美学思想的影响下对于造型、色彩、个性和审美情趣有独特的理解与表现,对当代首饰设计加以应用,找到能让大众获得共情和共鸣的设计点,既是一种传统的“再发明”,也是一种创意设计。中国画源远流长,传世佳作数量众多,其丰富的资源和样本库为中国风首饰设计提供了案例与新的设计思路,可以让中国风首饰从外观到内涵都体现出独特的民族性,满足市场对于中国风首饰设计的需求。

关键词：中国画民族性首饰设计中国风首饰

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