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SSRN 2024年

作者： Yin, Yong Li, Kezhi Jiang, Si Peng, Yue Zhu, Tianle Sun, Yifei Li, Junhua Li, Xiang School of Energy and Power Engineering Beihang University Beijing100191 China Institute of Engineering Technology Sinopec Catalyst Co. Ltd. Beijing101111 China State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing100084 China School of Materials Science and Engineering Beihang University Beijing100191 China School of Environmental Science and Engineering Hainan University Haikou570228 China Research Center for Advanced Energy and Carbon Neutrality Beihang University Beijing100191 China

Regeneration of highly toxic Arsenic (As) poisoned SCR catalysts is a huge challenge, because the strong interactions between As and the active component often leads to the loss or damage of active sites during the regeneration process. Herein, we develop a low-temperature plasma regeneration method that not only selectively removes As but also preserves the active components for commercial V2O5-WO3/TiO2 catalyst. More intriguingly, the catalyst after plasma regeneration achieves a significant catalytic performance enhancement, far surpassing the fresh V2O5-WO3/TiO2 catalyst. Under optimized regeneration conditions, the regenerated catalyst exhibits an As removal rate exceeding 99.5 ± 0.2% within 240 s, and a TOF value that was 11.1 and 2.4 times of the poisoned and fresh catalyst. Structural characterization reveals that the enhanced intrinsic activity of regenerated catalyst mainly stems from the As complete removal and subsequent transformation of monomeric VOx species into polymeric ones under H2 plasma environment. Multiple spectroscopic monitoring techniques unveil three stages in the plasma treatment process: (1) As reduction and removal, (2) surface polymerization of VOx species, and (3) vanadium embedded into TiO2 lattice. At low temperatures, the well regenerated catalysts with abundant polymeric VOx facilitate the nitrate-assisted dehydrogenation of adsorbed NH3 to key NH2 intermediates, thereby achieving superior NH3-SCR catalytic performance. This study not only provides a rapid regeneration strategy for poison selective separation from spent catalysts but also offers new insights into the precise control and design of active sites. © 2024, The Authors. All rights reserved.

关键词： Temperature

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Enhancing SiC/Nb brazed joints by negative thermal expansion (Sr0.2Ba0.8)TiO3 nanoparticle-coated Cu foam

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Ceramics International 2025年

作者： Han, Ao Wang, Gang Wang, Wei Zhao, Yu He, Rujie Tan, Caiwang Anhui Key Laboratory of High-performance Non-Ferrous Metal Materials Anhui Polytechnic University Wuhu241000 China of Anhui Province Wuhu241000 China School of Aviation and Materials Anhui Technical College of Mechanical and Electrical Engineering Wuhu241000 China Institute of Advanced Structure Technology Beijing Institute of Technology Beijing100081 China State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology Harbin150001 China

Negative coefficient of thermal expansion (Sr0.2Ba0.8)TiO3 (SBT) nanoparticles are produced by ball milling and twice sintering process and coated with Cu foam (Cuf) as an interlayer for brazing SiC and Nb. The influence of SBT content on the microstructural, shear strength, and fracture mechanism of SiC/Nb joints is investigated. In particular, SBT/Cuf foam is utilized to modify the coefficient of thermal expansion of the AgCuTi/SBT/Cuf/AgCuTi composite filler, resulting in a reduction of residual stresses in the joints. The residual stresses at the joints are calculated as well as analyzed the mechanism of residual stress relief by SBT. Following the introduction of the interlayer, the maximum shear strength of the joint is approximately 72 MPa, which is 164 % higher than the performance of the joint with uncoated SBT. © 2025 Elsevier Ltd and Techna Group S.r.l.

关键词： Negative thermal expansion

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MoO 3 -MoC/ [email protected] coupled heterostructures with strong connections and abundant interfaces for electromagnetic wave absorption

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Colloids and Surfaces A: Physicochemical and Engineering Aspects 2023年 668卷

作者： Yichao Yin Xiaojun Zeng Lei Xia Guangjie Xiong Hang Zhang Guoke Wei Aviation Key Laboratory of Science and Technology on Advanced Surface Engineering AVIC Manufacturing Technology Institute Beijing 100024 China School of Materials Science and Engineering Jingdezhen Ceramic University Jingdezhen 333403 China

Improving the electromagnetic wave (EMW) absorption capability at the thin thickness of heterostructures is critical but remains a great challenge. Here, we propose a MoO 3 @ZIF-67 core-shell heterostructure derived molybdenum trioxide- molybdenum carbide/ [email protected] carbon (MoO 3 -MoC/ [email protected] ) coupled heterostructure with a one-dimensional (1D) short rod-like structure for EMW absorption. A strong connection is constructed between [email protected] nanoparticles (NPs) and MoO 3 -MoC specie due to the pyrolysis strategy and in situ reaction between MoO 3 nanobelts and ZIF-67 rhombic dodecahedrons . The abundant heterointerfaces between N-doped carbon (NC) and metallic Co, [email protected] NPs and MoC species, [email protected] NPs and MoO 3 nanobelts, as well as MoC and MoO 3 nanobelts improve the interfacial polarization. Abundant defects, such as N heteroatoms and oxygen vacancies , are also established in the MoO 3 -MoC/ [email protected] coupled heterostructure. As a result, the MoO 3 -MoC/ [email protected] coupled heterostructure inherits excellent EMW absorption performance with a reflection loss ( R L ) value of − 64.3 dB at a thickness of 3.875 mm, outperforming many advanced EMW absorbers. This work shows the great potential of strong connections and abundant interfaces in heterostructure for improvements of EMW absorbers.

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Coupled Pacific Rim megadroughts contributed to the fall of the MingDynasty’s capital in 1644 CE

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Science Bulletin 2024年第19期69卷 3106-3114页

作者： Feng Chen Tao Wang Xiaoen Zhao Jan Esper Fredrik Charpentier Ljungqvist Ulf Büntgen Hans W.Linderholm David Meko Hongna Xu Weipeng Yue Shijie Wang Yujiang Yuan Jingyun Zheng Wei Pan Fidel Roig Martín Hadad Mao Hu Jiachang Wei Fahu Chen Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security Institute of International Rivers and Eco-SecurityYunnan UniversityKunming 650504China Southwest United Graduate School Kunming 650504China Climate Change Research Center and Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Department of Geography Johannes Gutenberg UniversityMainz 55099Germany Global Change Research Institute(CzechGlobe) Czech Academy of SciencesBrno 60300Czech Republic Department of History Stockholm UniversityStockholm 10691Sweden Bolin Centre for Climate Research Stockholm UniversityStockholm 10691Sweden Swedish Collegium for Advanced Study LinneanumUppsala 75238Sweden Department of Geography University of CambridgeCambridge CB23ENUK Department of Geography Faculty of ScienceMasaryk UniversityBrno 61137Czech Republic Swiss Federal Research Institute(WSL) Birmensdorf 8903Switzerland Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburg 40530Sweden Laboratory of Tree-Ring Research University of ArizonaTucson AZ 85721USA Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC FEMD) Nanjing University of Information Science and TechnologyNanjing 210044China Key Laboratory of Tree-ring Physical and Chemical Research Institute of Desert MeteorologyChina Meteorological AdministrationUrumqi 830002China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Digital Human Technology R&D and Application of Yunnan Provincial Department of Education Yunnan UniversityKunming 650504China Laboratorio de Dendrocronología e Historia Ambiental IANIGLA-CCT CONICET-Universidad Nacional de CuyoMendoza 5500Argentina Hémera Centro de Observación de La Tierra Escuela de Ingeniería ForestalFacultad de CienciasUniversidad MayorHuechuraba 85

Historical documents provide evidence for regional droughts preceding the political turmoil and fall of Beijing in 1644 CE,when more than 20 million people died in northern China during the late Ming famine ***,the role climate and environmental changes may have played in this pivotal event in Chinese history remains ***,we provide tree-ring evidence of persistent megadroughts from1576 to 1593 CE and from 1628 to 1644 CE in northern China,which coincided with exceptionally cold summers just before the fall of *** analysis reveals that these regional hydroclimatic extremes are part of a series of megadroughts along the Pacific Rim,which not only impacted the ecology and society of monsoonal northern China,but likely also exacerbated external geopolitical and economic *** finding is corroborated by last millennium reanalysis data and numerical climate model simulations revealing internally driven Pacific sea surface temperature variations and the predominance of decadal scale La Ni?a-like conditions to be responsible for precipitation decreases over northern China,as well as extensive monsoon regions in the *** teleconnection patterns provide a mechanistic explanation for reoccurring drought spells during the late Ming Dynasty and the environmental framework fostering the fall of Beijing in 1644 CE,and the subsequent demise of the Ming Dynasty.

关键词： Paleoclimate Beijing Precipitation reconstruction Climate-society interactions Tree rings Ming Dynasty

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Poling Above the Curie Temperature Driven Large Enhancement in Piezoelectric Performance of Mn Doped Pzt-Based Piezoceramics

SSRN

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SSRN 2023年

作者： Chen, Zhengran Hao, Yanshuang Huang, Jian Zhou, Zhiyong Li, Yaoguo Liang, Ruihong Key Laboratory of Inorganic Functional Materials and Devices Shanghai Institute of Ceramics Chinese Academy of Sciences 588 Heshuo Road Jiading District Shanghai201800 China School of Physical Science and Technology ShanghaiTech University Shanghai201210 China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences 588 Heshuo Road Jiading District Shanghai201800 China School of Chemistry and Materials Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Hangzhou310024 China Beijing Keeven Aviation Instrument Co. Ltd. China

The enhancement of piezoelectricity is usually in sacrifice of Curie temperature, which in turn limits its working temperature range. It is well known that there are some trade-off among the various performance parameters of most piezoelectric ceramics, and it is still difficult to achieve synergistic improvement in multiple parameters. Here, it is reported that the piezoelectric coefficient d33 of a 0.6 mol% Mn-doped Pb(Sb0.5Nb0.5)0.02Zr0.51Ti0.47O3 piezoelectric ceramics is increased to 436 pC N-1, and its electro-strain can reach 0.16% (d33* = 800 pm V-1) at 2 kV/mm by high-temperature poling, whose Curie temperature can still keep at 347 °C. The features of "hard" piezoelectric ceramics such as low dielectric loss (tgδ = 0.23%) and high mechanical quality factor (Qm = 546) are also preserved. Through structural characterization, combined with the theoretical results of phase field simulation, it is shown that its excellent piezoelectric performance originates from the highly oriented domain structure and small domain size after high temperature poling. On the other hand, the valence state transition of Mn3+ ions during high-temperature poling increases the defect vacancies and lattice distortion in ceramics, which keeps the acceptor-doped characteristic of the ceramics. © 2023, The Authors. All rights reserved.

关键词： Curie temperature

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The test of RF breakdowns of CPHS RFQ 29

The test of RF breakdowns of CPHS RFQ

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29th International Linear Accelerator Conference, LINAC 2018

作者： Ye, W.B. Zheng, S.X. Shi, J.R. Cheng, C. Xing, Q.Z. Guan, X.L. Wang, X.W. Wang, M.C. Ministry of Education Beijing100084 China Laboratory for Advanced Radiation Sources and Application Tsinghua University Beijing100084 China Department of Engineering Physics Tsinghua University Beijing100084 China State Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear Technology Xi'an710024 China

ISBN: (纸本)9783954501946

The high accelerating gradient is significant for a compact linear accelerator, and RF breakdowns is a limitation for the high gradient. This work aims to research RF breakdowns of a 325 MHz proton Radio Frequency Quadrupole (RFQ) accelerator of the Compact Pulsed Hadron Source (CPHS). The breakdown rate (BDR) of the RFQ has been measured. Breakdown waveforms have been recorded, which have been used for counting breakdown time distribution and analyzing the location of RF breakdowns. Content from this work may be used under the terms of the CC BY 3.0 licence (© 2018).

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High-throughput investigations of configurational-transformation-dominated serrations in CuZr/Cu nanolaminates

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Journal of Materials Science & technology 2020年第18期52卷 192-199页

作者： William Yi Wang Bin Gana Deye Lin Jun Wang Yiguang Wang Bin Tang Hongchao Kou Shunli Shang Yi Wang Xingyu Gao Haifeng Song Xidong Hui Laszlo J.Kecskes Zhenhai Xia Karin A.Dahmen Peter K.Liaw Jinshan Lia Zi-Kui Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an.710072China Beijing Key Laboratory of Advanced High Temperature Materials Central Iron and Steel Research InstituteBeijing100081China IMDEA Materials Institute Calle Eric Kandel 2GetafeMadrid28906Spain CAEP Software Center for High Performance Numerical Simulation Institute of Applied Physics and Computational MathematicsBeijing100088China Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPA16802USA State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing100083China Hopkins Extreme Materials Institute Johns Hopkins UniversityBaltimoreMD21218USA Department of Physics University of Illinois at Urbana ChampaignUrbanaIL61801USA Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN37996USA

Metallic amorphous/crystalline(A/C)nanolaminates exhibit excellent ductility while retaining their high ***,the underlying physical mechanisms and the resultant structural changes during plastic deformation still remain *** the present work,the structure-property relationship of CuZr/Cu A/C nanolaminates is established through integrated high-throughput micro-compression tests and molecular dynamics simulations together with high-resolution transmission electron *** serrated flow of nanolaminates results from the formation of hexagonal-close-packed(HCP)-type stacking faults and twins inside the face-centered-cubic(FCC)Cu nano-grains,the body-centered-cubic(BCC)-type ordering at their grain boundaries,and the crystallization of the amorphous CuZr *** serration behavior of CuZr/Cu A/C nanolaminates is determined by several factors,including the formation of dense dislocation networks from the multiplication of initial dislocations that formed after yielding,weak-spots-related configurational-transitions and shear-transition-zone activities,and deformation-induced *** present work provides an insight into the heterogeneous deformation mechanism of A/C nanolaminates at the atomic scale,and mechanistic base for the microstructural design of self-toughening metallic-glass(MG)-based composites and A/C nanolaminates.

关键词： Nanolaminates Serration Configurational transformation Molecular dynamics Metallic glass

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Research on a high-current CW proton hybrid accelerating cavity incorporating coupled four-vane RFQ and CH DTL structures

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Journal of Instrumentation 2025年第5期20卷 P05047-P05047页

作者： Tuo, Mingze Wang, Baichuan Liu, Wolong Zhuo, Xin Yang, Fuyu Wang, Minwen Yan, Yihua Zhang, Xiaodong Wang, Zhongming Xing, Qingzi Key Laboratory of Particle and Radiation Imaging Tsinghua University Ministry of Education Beijing100084 China National Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear Technology Xi'an710024 China Laboratory for Advanced Radiation Sources and Application Tsinghua University Beijing100084 China Department of Engineering Physics Tsinghua University Beijing100084 China

To enhance the accelerating efficiency of the high-current accelerator for a neutron source, a 100-mA, 162.5-MHz, CW compact hybrid accelerating cavity incorporating inductively coupled four-vane RFQ and CH DTL structures is designed in this paper. The dynamics design, the RF structure design, error analysis, and water-cooling design of the hybrid cavity have been accomplished. The proton beam is accelerated from 80 keV to 0.8 MeV via the RFQ and is further accelerated to 3 MeV by the DTL. The coupling modes of the two-resonant-cavity are analyzed. The designed length of the hybrid accelerating cavity is 3.94 m, and its total power consumption is 101.3 kW. © 2025 IOP Publishing Ltd and Sissa Medialab. All rights, including for text and data mining, AI training, and similar technologies, are reserved.

关键词： Accelerator Applications Accelerator modelling and simulations (multi-particle dynamics, single-particle dynamics) Beam dynamics

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A comprehensive assessment of anthropogenic impacts, contamination, and ecological risks of toxic elements in sediments of urban rivers: A case study in Qingdao, East China

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Environmental Advances 2022年 7卷

作者： Gu, Xiang Lin, Chunye Wang, Baodong Wang, Jing Ouyang, Wei State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China MNR Key Laboratory of Marine Eco-Environmental Science and Technology First Institute of Oceanography Ministry of Natural Resources Qingdao 266061 China College of Water Science Beijing Normal University Beijing 100875 China Advanced Interdisciplinary Institute of Environment and Ecology Beijing Normal University Zhuhai 519087 China

Urban river sediments usually serve as a sink for potentially toxic elements (PTEs) during the process of urbanization. A systematic evaluation of human influence, contamination, and risk assessment of PTEs in urban river sediments is essential for sustaining river health. In this study, 24 sediment samples were collected from 5 rivers in Qingdao, a coastal urbanized city in East China. Zinc had the highest concentration (141 ± 134 mg/kg), followed by Cr, Cu, Pb, Ni, Co, As, and Cd. Generally, the PTE concentrations were higher in eastern rivers than those in western rivers affected by intensive industrialization and urbanization. The principal component analysis identified three principal components: natural origins (As, Co, Cr, and Ni), urban activities (Cd, Cu, Pb, and Zn), and atmospheric deposition (Pb), respectively. The excessive concentrations of Cd and Pb were frequently appeared in the sampling sites, with the anthropogenic contribution rates of 8.4%–77% and 6.6%–87%, respectively. Additionally, the river sediments experienced moderate contamination of As, Cd, Cu, Pb, and Zn. Among the PTEs, Cd had moderate ecological risk and others had low risk. The results of Monte Carlo simulation were generally in accordance with the detected contamination and risk levels, except for several elements (Cu and Zn) with huge spatial heterogeneity. According to the Monte Carlo simulation, the river sediments could undergo extremely high contamination and high ecological risk of the PTEs in the worst situation. Thus, it becomes essential that PTEs in the urban rivers should not be overlooked before their discharge into the sea. © 2021 The Author(s)

关键词： Excessive concentration Monte Carlo simulation Risk assessment Toxic elements Urban river

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Continuous and comprehensive atmospheric observations in Beijing:a station to understand the complex urban atmospheric environment

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Big Earth Data 2020年第3期4卷 295-321页

作者： Yongchun Liu Chao Yan Zemin Feng Feixue Zheng Xiaolong Fan Yusheng Zhang Chang Li Ying Zhou Zhuohui Lin Yishou Guo Ying Zhang Li Ma Wenshuo Zhou Zhikun Liu Lubna Dada Kaspar Dallenbach Jenni Kontkanen Runlong Cai Tommy Chan Biwu Chu Wei Du Lei Yao Yonghong Wang Jing Cai Juha Kangasluoma Tom Kokkonen Joni Kujansuu Anton Rusanen Chenjuan Deng Yueyun Fu Rujing Yin Xiaoxiao Li Yiqun Lu Yiliang Liu Chaofan Lian Dongsen Yang Weigang Wang Maofa Ge Yuesi Wang Douglas R.Worsnop Heikki Junninen Hong He Veli-Matti Kerminen Jun Zheng Lin Wang Jingkun Jiang Tuukka Petaja Federico Bianchi Markku Kulmala Aerosol and Haze Laboratory Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijingChina Institute for Atmospheric and Earth System Research/Physics Faculty of ScienceUniversity of HelsinkiHelsinkiFinland State Key Joint Laboratory of Environment Simulation and Pollution Control State Environmental Protection Key Laboratory of Sources and Control of Air Pollution ComplexSchool of EnvironmentTsinghua UniversityBeijingChina State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijingChina Department of Environmental Science&Engineering Fudan UniversityShanghaiChina State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijingChina Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Nanjing University of Information Science&TechnologyNanjingChina State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Aerodyne Research Inc. BillericaMassachusettsUSA Institute of Physics University of TartuTartuEstonia Joint International Research Laboratory of Atmospheric and Earth System Sciences School of Atmospheric SciencesNanjing UniversityNanjingChina

Due to profound impact on climate and human health,air quality has attracted attention from all levels of the civil *** key step in the provision of required tools for the society to tackle the complex air quality problem is to characterize it in a comprehensive manner with a long-term ***,we describe a continuous and comprehensive observation station and its accompanying state-ofthe-art instrumentation that was established to investigate the complex urban atmospheric environment in a rapidly developing Chinese *** station,located in downtown Beijing,aims to study air quality by identifying the major atmospheric pollutants and key processes determining their formation and loss mechanisms.A few hundreds of parameters are continuously measured with the state-of-the-art instruments,including trace gas concentrations,aerosol particle size distributions,and mass concentrations,covering aerosol particle chemical composition from molecules to micrometer-sized aerosol *** produced long-term,comprehensive big data with around 1�10^(11)bytes per *** this paper,we provide an overview on the facilities of the station,the instrumentation used,the workflow of continuous observations and examples of results from 2018 to 2019 and a basis for establishing a modern long-term,comprehensive atmospheric urban observation station in other megacities.

关键词： Continuous and comprehensive atmospheric observation air pollution complex photochemical smog haze new particle formation

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