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SO2 Poisoning, Regeneration, and Impact on Dimer-Cu Intermediates in the NH3-SCR Reaction over Cu-Zeolites

Environmental science & technology 2025年第22期59卷 2025 May 29页

作者： Wenqing Ding Yu Fu Huibin Liu Tongliang Zhang Yu Sun Zhongqi Liu Sen Xue Xuewang Han Jinpeng Du Peirong Chen Yulong Shan Yunbo Yu Hong He School of Chemistry and Chemical Engineering Nanchang University Nanchang 330031 China. Ganjiang Innovation Academy Chinese Academy of Sciences Ganzhou 341119 China. State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control National Engineering Laboratory for VOCs Pollution Control Technology and Equipment School of Environment and Energy South China University of Technology Guangzhou 510006 China. Weichai Power Co. Ltd. Weifang 261061 China. State Key Laboratory of Engine and Powertrain System Weifang 261061 China. Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China.

This study demonstrates that Al-rich, high-Cu-loaded Cu-SSZ-13 exhibits superior resistance to SO poisoning under actual SCR conditions. The high Cu content mitigates the risk of SO-induced structural degradation. A key finding is that lower regeneration temperatures can lead to more severe secondary poisoning, while high temperatures induce hydrothermal aging. Thus, controlling the regeneration temperature is critical for maintaining long-term catalyst stability. Additionally, experimental results and DFT calculations show that SO preferentially reacts with dimer-Cu species, especially hydrogenated dimer-Cu ([Cu(NH)(OH)O]), resulting in significant sulfate accumulation. This interaction inhibits the redox cycle of Cu/Cu, thereby suppressing low-temperature activity. Overall, this work elucidates the mechanisms of SO-induced deactivation in Cu-zeolite SCR catalysts and provides valuable insights into designing Cu-SSZ-13 catalysts with enhanced sulfur resistance through Cu-Al co-optimization.

关键词： Cu-SSZ-13 DRUVS NH3-SCR SO2 poisoning dimer-Cu

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An 8-Channel RF Coil based on Microstrip Yagi-antenna for 7T Magnetic Resonance Imaging

An 8-Channel RF Coil based on Microstrip Yagi-antenna for 7T...

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IEEE International Symposium on Antennas and Propagation

作者： Ke He Mengxia Yu E Zhao Guiping Li Maoyan Wang Jing Ma School of Physics University of Electronic Science and Technology of China (UESTC) Chengdu China Science and Technology on Special System Simulation Laboratory Beijing China

ISBN: (数字)9781728166704

ISBN: (纸本)9781728166704;9781728166711

A new RF coil based on microstrip Yagi-antenna for 7T magnetic resonance imaging (MRI) is presented in this paper. The RF coil element consists of a driver which is a pair of dipoles printed on the dielectric substrate and two reflectors distributed on either sides of the driver. simulation results show that the proposed 8-channel RF coil array with these elements has high magnetic field intensity and uniform magnetic field distribution in the transverse plane, and can also maintain relatively low specific absorption rate (SAR) in the human body electromagnetic model. In addition, by comparing the RF field distribution of healthy organs and diseased organs, the feasibility of 8-channel RF coil array for human body imaging in MRI system is confirmed.

关键词： Radio frequency Microstrip antenna arrays Magnetic resonance imaging Electromagnetic modeling Specific absorption rate Magnetic fields Microstrip

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Strengthening the three-dimensional comprehensive observation system of multi-layer interaction on the Tibetan Plateau to cope with the warming and wetting trend

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Atmospheric and Oceanic science Letters 2022年第4期15卷 67-71页

作者： Yaoming Ma Binbin Wang Xuelong Chen Lei Zhong Zeyong Hu Weiqiang Ma Cunbo Han Maoshan Li Land–Atmosphere Interaction and its Climatic Effects Group State Key Laboratory of Tibetan Plateau Earth SystemResources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina College of Atmospheric Science Lanzhou UniversityLanzhouChina National Observation and Research Station for Qomolongma Special Atmospheric Processes and Environmental Changes DingriChina Kathmandu Center of Research and Education Chinese Academy of SciencesBeijingChina China–Pakistan Joint Research Center on Earth Sciences Chinese Academy of SciencesIslamabadPakistan School of Earth and Space Sciences University of Science and Technology of ChinaHefeiChina CAS Center for Excellence in Comparative Planetology USTCHefeiChina Frontiers Science Center for Planetary Exploration and Emerging Technologies University of Science and Technology of ChinaHefeiChina Jiangsu Collaborative Innovation Center for Climate Change NanjingChina Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina School of Atmospheric Science Chengdu University of Information TechnologyChengduChina

Changes in the water cycle on the Tibetan Plateau(TP)have a significant impact on local agricultural production and livelihoods and its downstream *** the background of widely reported warming and wetting,the hydrological cycle has accelerated and the likelihood of extreme weather events and natural disasters occurring(i.e.,snowstorms,floods,landslides,mudslides,and ice avalanches)has also intensified,especially in the highelevation mountainous ***,an accurate estimation of the intensity and variation of each component of the water cycle is an urgent scientific question for the assessment of plateau environmental *** the transformation and movement of water between the atmosphere,biosphere and hydrosphere,the authors highlight the urgent need to strengthen the three-dimensional comprehensive observation system(including the eddy covariance system;planetary boundary layer tower;profile measurements of temperature,humidity,and wind by microwave radiometers,wind profiler,and radiosonde system;and cloud and precipitation radars)in the TP region and propose a practical implementation *** construction of such a three-dimensional observation system is expected to promote the study of environmental changes and natural hazards prevention.

关键词： Plateau warming and wetting Hydrological cycle Three-dimensional comprehensive observation system of multi-layer interaction Mountain-disaster response Tibetan Plateau

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Comparison of simulation and Measurements of Time-Domain Field-to-Line Coupling in Bounded wave Simulator

Comparison of Simulation and Measurements of Time-Domain Fie...

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Longquan Zhong Jiangchuan Lin Feng Qin Chun Yang Chang Liu Hua Huang Complicated Electromagnetic Environment Laboratory of CAEP (of Institute of Applied Electronics) Mianyang China Software Center for High Performance Numerical Simulation of CAEP (of Institute of Applied Physics and Computational Mathematics) Beijing China Science and Technology on High Power Microwave Laboratory (of Institute of Applied Electronics) Mianyang China

This paper presents an analysis of time-domain electromagnetic pulse coupling to single wire. A field-to-line coupling model was established. The simulation is performed using the uniform plane wave excitation defined by measured high-altitude nuclear electromagnetic pulse (HEMP) field signal, the induced currents of two load terminals are simulated. The validation measurement of single wire above the grounding plate is conducted in the bounded wave simulator. The frequency response of the actual coupled current signal monitoring system is considered in the data preprocessing. The comparison between simulation and measurement results show that the peak amplitude and waveform can coincide well.

关键词： Couplings Pulse measurements Current measurement Wires Predictive models EMP radiation effects Time-domain analysis

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Vertical Transport of Ultrafine Particles and Turbulence Evolution Impact on New Particle Formation at the Surface & Canton Tower

SSRN

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SSRN 2023年

作者： Wu, Hao Li, Zhanqing Hai, Shangfei Gao, Yang Jiang, Jingkun Zhao, Bin Cribb, Maureen Zhang, Dongmei Pu, Dongyang Liu, Mengqi Wang, Chunling Lan, Jing Wang, Yuying Key Laboratory of China Meteorological Administration Atmospheric Sounding School of Electrical Engineering Chengdu University of Information Technology Chengdu610225 China Department of Atmospheric and Oceanic Science University of Maryland College ParkMD20742 United States College of Oceanic and Atmospheric Sciences Ocean University of China Qingdao266100 China Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Laboratory of Marine Environmental Science and Ecology Ministry of Education Ocean University of China Qingdao266100 China School of Environment State Key Joint Laboratory of Environment Simulation and Pollution Control Tsinghua University Beijing100084 China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing100084 China College of Global Change and Earth System Science Beijing Normal University Beijing100875 China Guangzhou Climate and Agrometeorology Center Guangzhou511430 China Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science & Technology Nanjing210044 China

New particle formation (NPF) is a key process occurring in the planetary boundary layer (PBL). Newly formed particles are an important source of aerosols and cloud condensation nuclei (CCN) that influence clouds and climate, while the distribution of these new particles at different altitudes has rarely been studied. In-situ measurements of ultrafine particles (UFP) observed at the ground and at the top of the Canton Tower (454 m) located in downtown Guangzhou in southern China were analyzed using the measurements of multiple meteorological and physicochemical quantities, as both observed during a field campaign and simulated with the WRF-chem model. We found that turbulence and NPF characters vary considerably with heights, with UFP concentration diminishing by half from the surface to the tower top. This indicates the UFP transports upward from the ground in the lower boundary layer. A consistent relationship is established between the occurrences of NPF and the evolution of turbulence. The correlation between the exchange ratio at the tower top has correlated well with nucleation growth, suggesting that turbulence can play an important role in the episodes of NPF growth, whose growth rate is closely related to the turbulence exchange ratio, effectively dictating the ultrafine particle concentration before and during the lockdown period. A new mechanism is thus hypothesized: NPF happens eailer near the surface and grows faster at the upper PBL, attributed to condensable vapors being transported by turbulent vertical mixing in the boundary layer. Model simulations using the WRF-Chem model reveal that the exchange ratio changed the NPF parameters, supporting the proposed mechanism that the evolution of the PBL variation has a significant impact on NPF, which should not be omitted in the NPF research, since this physical factor could be a dominant one in the NPF mechanism. © 2023, The Authors. All rights reserved.

关键词： Turbulence

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Quantitatively determine the dominant driving factors of the spatial–temporal changes of vegetation NPP in the Hengduan Mountain area during 2000-2015

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Journal of Mountain science 2021年第2期18卷 427-445页

作者： CHEN Shu-ting GUO Bing ZHANG Rui ZANG Wen-qian WEI Cui-xia WU Hong-wei YANG Xiao ZHEN Xiao-yan LI Xing ZHANG Da-fu HAN Bao-min ZHANG Hai-ling School of Civil Architectural Engineering Shandong University of TechnologyZibo 255000China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Land use Ministry of Natural ResourcesChina Land Survey and Planning InstituteBeijing 100035China Key Laboratory for Digital Land and Resources of Jiangxi Province East China University of TechnologyNanchang 330013China Key Laboratory of National Geographic Census and Monitoring Ministry of Natural ResourcesWuhan 430079China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100101China Key Laboratory of UrbanLand Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhen 518000China Key Laboratory of Meteorology and Ecological Environment of Hebei Province Shijiazhuang 050021China Land Satellite Remote Sensing Application Center Ministry of Natural ResourcesBeijing 100048China College of Geological Engineering and Geomatics Chang'an UniversityXi'an 710054China

The Hengduan mountain area,located in the upper reaches of the Yangtze River of China,is an important ecological barrier that significantly impacts the climate and ecological environment of the surrounding region and western China as a *** paper introduces the gravity center model used to analyze the spatial-temporal variation patterns of vegetation Net Primary Productivity(NPP)from 2000 to 2015,which were determined by the use of MOD17 A3 NPP ***,the dominant driving factors of the spatial–temporal changes of vegetation NPP of the Hengduan Mountain area were quantitatively determined with a geographical detector over *** results revealed that:(1)From 2000 to 2015,there was an increasing trend of vegetation NPP in the Hengduan mountain *** the whole study region,the vegetation NPP with a mean value of 611.37 gC·m^(-2)·a^(-1) indicated a decreasing trend from southeast to northwest in terms of spatial distribution.(2)The gravity centers of vegetation NPP in 2000-2015 were mainly concentrated in Zhongdian *** the study period,the gravity center of vegetation NPP moved northward,which indicated that the increment and increasing rate of vegetation NPP in the northern parts were greater than that of the southern areas.(3)The vegetation NPP showed a moderately positive correlation with temperature,accumulated temperature(>10℃),and sunshine,while there was an overall negative relationship between NPP and precipitation.(4)The dominant factors and interactive dominant factors changed in different subregions over different segments of the study *** dominant factors of most sub-regions in Hengduan mountain were natural factors,and the climate change factors played an increasingly greater role over the 16 years of the study period.

关键词： Vegetation NPP Spatial-temporal distribution Driving factors Geographic detector Land use change

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Flow Visualization of Centrifugal Pump by the Combination of LIF and PIV 1

Flow Visualization of Centrifugal Pump by the Combination of...

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1st International Conference on Sensing, Measurement and Data Analytics in the Era of Artificial Intelligence, ICSMD 2020

作者： Zhang, Qi Gu, Hanyang Liu, Shuai Li, Junlong Tan, Sichao Su, Jianke Shanghai Jiao Tong University School of Nuclear Science and Engineering China Harbin Engineering University Fundamental Science on Nuclear Safety and Simulation Technology Laboratory Harbin China Caea Support Center of Nuclear Technology Beijing China

ISBN: (纸本)9781728192772

The visual experimental system for the centrifugal pump was established. The mock centrifugal pump with six curving semi-open impellers was manufactured by polymethyl methacrylate. The flow characteristics inside the mock centrifugal pump was studied by the combination of laser induced fluorescence (LIF) and particle image velocimetry (PIV). The polyamide resin particles were dissolved into the fluid of the circulation for PIV analysis, and fluorescent dye rhodamine B was head-on injected to the impellers for LIF analysis. The front plane of the impellers was covered by Nd: YAG laser sheet, one CCD camera collected the reflected laser light from the particles. Synchronously, another camera collected the fluorescence of rhodamine B. The velocity distribution characteristic was presented, and the time evolution of injected dye in the channel between impeller and septum was obtained. The inlet fluid moved circumferentially along the impeller under centrifugal force, the central region had smaller velocity. The injected dye gathered into blocks near the central area, and was evenly distributed near the edge of the pump impellers. The combination of LIF and PIV was proved to be credible method in the research of centrifugal pump. © 2020 IEEE.

关键词： Fluorescence

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Contaction of Atoms for Outstanding Dielectric Characteristics in Kx-Passivated Polymer Dielectrics

SSRN

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SSRN 2022年

作者： Li, Xiao-Fen Wang, Tian-Yu Liu, Bai-Xin Liu, Jian-Bo Zhang, Gui-Xin Wang, Zhong Lin School of Materials Science and Engineering Tsinghua University Beijing100084 China State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical Engineering Tsinghua University Beijing100084 China CAS Center for Excellence in Nanoscience Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Beijing100083 China School of Nanoscience and Technology University of Chinese Academy of Sciences Beijing100049 China School of Material Science and Engineering Georgia Institute of Technology AtlantaGA30332 United States

High dielectric characteristics polymer dielectrics are crucial for high-power, high-integration, and high-energy storage density electrical devices and film capacitors. However, polymer dielectrics accumulate much charge during operation, causing local electric field distortion and flashover or breakdown. The deep-level defect state (electron/hole accumulation center) is a fundamental factor affecting dielectric strength. Unfortunately, related research, especially on passivating deep-level defects in polymer dielectrics, is minimal. In this paper, based on experiments and first-principles calculations, it is found that KX (X=F, Cl, Br, I) effectively passivates deep-level defect states in polymer dielectrics. Further analysis of the physical passivation mechanism reveals that the deep-level defect cation passivation principle is the cation dipole effect on polymers. The principle of anion passivation of deep-level defects by suspending anions and cations is the key to producing more stable C covalent bonds. This stable covalent bond transfers the local charge from the C with the lone electron pair that originally contains the hanging bond. Therefore, some transfer occurs and the anion implements effective passivation. This paper addresses the design of high-performance polymer dielectrics, providing a reference for experimental and theoretical analyses. © 2022, The Authors. All rights reserved.

关键词： Passivation

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Effect of potential HONO sources on peroxyacetyl nitrate(PAN)formation in eastern China in winter

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Journal of Environmental sciences 2020年第8期32卷 81-87页

作者： Jingwei Zhang Yitian Guo Yu Qu Yong Chen Ruipeng Yu Chaoyang Xue Rui Yang Qiang Zhang Xingang Liu Yujing Mu Jing Wang Can Ye Haihan Zhao Qiangqiang Sun Ziwen Wang Junling An State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China College of Earth Science University of Chinese Academy of SciencesBeijing 100049China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Guangzhou Meteorological Observatory Guangzhou 511430China Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijingChina Collaborative Innovation Center for Regional Environmental Quality BeijingChina State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of Land Science and Technology China Agricultural UniversityBeijing 100193China Qinghai Climate Center Qinghai Meteorological BureauXiningQinghai 810001China

As an important secondary photochemical pollutant,peroxyacetyl nitrate(PAN)has been studied over decades,yet its simulations usually underestimate the corresponding observations,especially in polluted *** observations in north China found unusually high concentrations of PAN during wintertime heavy haze events,but the current model still cannot reproduce the observations,and researchers speculated that nitrous acid(HONO)played a key role in PAN *** the first time we systematically assessed the impact of potential HONO sources on PAN formation mechanisms in eastern China using the Weather Research and Forecasting/Chemistry(WRF-Chem)model in February of *** results showed that the potential HONO sources significantly improved the PAN simulations,remarkably accelerated the RO x(sum of hydroxyl,hydroperoxyl,and organic peroxy radicals)cycles,and resulted in 80%–150%enhancements of PAN near the ground in the coastal areas of eastern China and 10%–50%enhancements in the areas around 35–40°N within 3 km during a heavy haze *** direct precursors of PAN were aldehyde and methylglyoxal,and the primary precursors of PAN were alkenes with C>3,xylenes,propene and *** above results suggest that the potential HONO sources should be considered in regional and global chemical transport models when conducting PAN studies.

关键词： Nitrous acid(HONO) Peroxyacetyl nitrate(PAN) WRF-Chem model Winter haze RO x cycles

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Diffusion mechanism simulation of cloud manufacturing complex network based on cooperative game theory

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Journal of systems Engineering and Electronics 2018年第2期29卷 321-335页

作者： GENG Chao QU Shiyou XIAO Yingying WANG Mei SHI Guoqiang LIN Tingyu XUE Junjie JIA Zhengxuan Economics and Management School Harbin Institute of Technology at Weihai Beijing Complex Product Advanced Manufacturing Engineering Research Center Beijing Simulation Center State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System Engineering Science and Technology on Space System Simulation Laboratory Beijing Simulation Center

Cloud manufacturing is a specific implementation form of the "Internet + manufacturing" strategy. Why and how to develop cloud manufacturing platform(CMP), however, remains the key concern of both platform operators and users. A microscopic model is proposed to investigate advantages and diffusion forces of CMP through exploration of its diffusion process and mechanism. Specifically, a three-stage basic evolution process of CMP is innovatively proposed. Then, based on this basic process, a more complex CMP evolution model has been established in virtue of complex network theory, with five diffusion forces identified. Thereafter, simulations on CMP diffusion have been conducted. The results indicate that, CMP possesses better resource utilization,user satisfaction, and enterprise utility. Results of simulation on impacts of different diffusion forces show that both the time required for CMP to reach an equilibrium state and the final network size are affected simultaneously by the five diffusion forces. All these analyses indicate that CMP could create an open online cooperation environment and turns out to be an effective implementation of the "Internet + manufacturing" strategy.

关键词： complex network cloud manufacturing innovation diffusion network effect Gale-Shapley algorithm cooperative game theory

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