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Coarse particulate matter air quality in East Asia: implications for fine particulate nitrate

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arXiv 2022年

作者： Zhai, Shixian Jacob, Daniel J. Shah, Viral Yang, Laura Hyesung Zhang, Qiang Sun, Yele Wang, Shuxiao Luo, Gan Yu, Fangqun Woo, Jung-Hun Kim, Younha Kim, Hwajin Dibb, Jack E. Lee, Taehyoung Han, Jin-Seok Li, Ke Liao, Hong John A. Paulson School of Engineering and Applied Sciences Harvard University CambridgeMA02138 United States Department of Earth System Science Tsinghua University Beijing100084 China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing100029 China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Tsinghua University Beijing100084 China Atmospheric Sciences Research Center University at Albany AlbanyNY12226 United States Department of Civil and Environmental Engineering Konkuk University Seoul05029 Korea Republic of Laxenburg 2361 Austria Department of Environmental Health Sciences Graduate School of Public Health Seoul National University Seoul08826 Korea Republic of Institute for the Study of Earth Oceans and Space University of New Hampshire DurhamNH03824 United States Department of Environmental Science Hankuk University of Foreign Studies Yongin449791 Korea Republic of Department of Environmental and Energy Engineering Anyang University Anyang14028 Korea Republic of Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment Technology School of Environmental Science and Engineering Nanjing University of Information Science and Technology Nanjing210044 China

Air quality network data in China and South Korea show very high year-round mass concentrations of coarse particulate matter (PM) between 2.5 μm and 10 μm aerodynamic diameter, as inferred by the difference between PM10 and PM2.5 observations. This coarse PM averages 47 μg m-3 in the North China Plain (NCP) region in 2015-2019 and 21 μg m-3 in the Seoul Metropolitan Area (SMA). It is dominantly contributed by urban fugitive dust, rather than by natural dust as is often presumed. Concentrations decreased by 21% from 2015 to 2019 and further dropped abruptly in 2020 due to COVID-19 reductions in construction and vehicle traffic. This anthropogenic coarse PM is generally not included in air quality models but acts as a sink of nitric acid (HNO3), thus affecting fine particulate nitrate which is a major air quality concern in China and South Korea. GEOS-Chem model simulation of surface and aircraft observations from the KORUS-AQ campaign over the SMA in May-June 2016 shows that consideration of anthropogenic coarse PM largely resolves the previous model overestimate of PM1 nitrate. Anthropogenic coarse PM in the model increases the sensitivity of PM2.5 nitrate to ammonia (NH3) emission in winter. In summer, anthropogenic coarse PM directly affects PM2.5 nitrate by HNO3 uptake, and we find that the decrease of anthropogenic coarse PM over 2015-2019 offset the PM2.5 nitrate reductions expected from decreasing NOx and NH3 emissions. Copyright © 2022, The Authors. All rights reserved.

关键词： Nitrates

Nonlinear electronic stopping of negatively charged particles in liquid water

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Physical Review Research 2023年第3期5卷 033063-033063页

作者： Natalia E. Koval Fabiana Da Pieve Bin Gu Daniel Muñoz-Santiburcio Jorge Kohanoff Emilio Artacho CIC Nanogune BRTA 20018 Donostia-San Sebastián Spain Centro de Física de Materiales CFM-MPC 20018 Donostia-San Sebastián Spain Royal Belgian Institute for Space Aeronomy 1180 Brussels Belgium Atomistic Simulation Centre Queen's University Belfast Belfast BT7 1NN Northern Ireland United Kingdom Department of Physics Nanjing University of Information Science and Technology 210044 Nanjing China Instituto de Fusión Nuclear “Guillermo Velarde ” Universidad Politécnica de Madrid 28006 Madrid Spain Donostia International Physics Center DIPC 20018 Donostia-San Sebastián Spain Theory of Condensed Matter Cavendish Laboratory University of Cambridge J. J. Thomson Avenue Cambridge CB3 0HE United Kingdom Ikerbasque Basque Foundation for Science 48011 Bilbao Spain

We present real-time time-dependent density-functional-theory calculations of the electronic stopping power for negative and positive projectiles (electrons, protons, antiprotons, and muons) moving through liquid water. After correction for finite mass effects, the nonlinear stopping power obtained in this paper is significantly different from the previously known results from semiempirical calculations based on the dielectric response formalism. Linear-nonlinear discrepancies are found both in the maximum value of the stopping power and the Bragg peak's position. Our results indicate the importance of the nonlinear description of electronic processes, particularly, for electron projectiles, which are modeled here as classical point charges. Our findings also confirm the expectation that the quantum nature of the electron projectile should substantially influence the stopping power around the Bragg peak and below.

关键词： First-principles calculations Radiation damage Water Density functional calculations Time-dependent DFT

Heteroaggregation of functionalized nanoplastics with Al 2 O 3 particles in aquatic environments

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Chemical Engineering Journal 2025年 518卷

作者： Xia Liu Yating Zhao Tongtao Yue Bo Gao Xing Guo Meng Wang Wenli Su Chu Wang Lu Liu Yanhui Dai Zhenyu Wang Jian Zhao Baoshan Xing Frontiers Science Center for Deep Ocean Multispheres and Earth System Institute of Coastal Environmental Pollution Control Key Laboratory of Marine Environment and Ecology (Ministry of Education) Ocean University of China Qingdao 266100 China Laboratory for Marine Ecology and Environmental Science Qingdao Marine Science and Technology Center Qingdao 266237 China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Beijing 100038 China Institute of Environmental Processes and Pollution Control and School of Environment & Ecology Jiangnan University Wuxi 214122 China Stockbridge School of Agriculture University of Massachusetts Amherst MA 01003 United States

Heteroaggregation is critical for the distribution, transport, and bioavailability of nanoplastics in aquatic environments, but the heteroaggregation of functionalized nanoplastics with Al 2 O 3 particles is unknown. In this work, strong heteroaggregation occurred between negatively charged nanoplastics (PS-plain and PS-COOH) and positively charged Al 2 O 3 particles at pH 6.0, and electrostatic attraction was identified as the dominant force. Weak heteroaggregation was also found for positively charged PS-NH 2 , in which hydrogen bonding and van der Waals force were the main mechanism based on molecular dynamics simulations and Fourier transform infrared analysis. Maximum heteroaggregation rates and hydrodynamic diameters of PS-Al 2 O 3 heteroaggregates were observed at the ratio of 0.005 (PS-COOH/Al 2 O 3 ), which could be explained by the minimum net charge of the heteroaggregates in the binary system and the specific heteroaggregate configurations (bridging). Additionally, the effect of humic acid (HA) on PS-Al 2 O 3 heteroaggregation under different interaction sequences was studied for the first time. Notably, pre-treated with HA on PS-COOH nanoplastics or Al 2 O 3 mitigated the heteroaggregation more obviously relative to coating HA on PS-Al 2 O 3 heteroaggregates ((Al 2 O 3 -PS-COOH)-HA). Pre-adsorbed HA weakened electrostatic interaction and enhanced steric interactions between PS-COOH and Al 2 O 3 . For the three nanoplastics, homoaggregation of Al 2 O 3 facilitated PS-Al 2 O 3 heteroaggregation under low ionic strength (below 50 mM NaCl) while this effect was not evident under high ionic strength conditions. Slight disturbance (e.g., shaking) was found to enhance the heteroaggregation between PS nanoplastics and Al 2 O 3 , while strong disturbance (e.g., sonication) could break down PS-Al 2 O 3 heteroaggregates irreversibly. These results are useful for better understanding the transport and fate of nanoplastics in the natural aquatic environments.

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Fine structures of radio bursts from flare star AD Leo with FAST observations

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arXiv 2023年

作者： Zhang, Jiale Tian, Hui Zarka, Philippe Louis, Corentin K. Lu, Hongpeng Gao, Dongyang Sun, Xiaohui Yu, Sijie Chen, Bin Cheng, Xin Wang, Ke School of Earth and Space Sciences Peking University Beijing100871 China LESIA Observatoire de Paris Université PSL Sorbonne Université Université Paris Cité CNRS Meudon92190 France USN Observatoire de Paris Université PSL Univ Orléans CNRS Nançay18330 France School of Cosmic Physics DIAS Dunsink Observatory Dublin Institute for Advanced Studies Dublin 15 Ireland Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space Sciences Shandong University Shandong Weihai264209 China School of Physics and Astronomy Yunnan University Kunming650500 China Center for Solar-Terrestrial Research New Jersey Institute of Technology NewarkNJ07102 United States School of Astronomy and Space Science Nanjing University Nanjing210093 China Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry of Education Nanjing210093 China Max Planck Institute for Solar System Research Göttingen37077 Germany Kavli Institute for Astronomy and Astrophysics Peking University Beijing100871 China

Radio bursts from nearby active M-dwarfs have been frequently reported and extensively studied in solar or planetary paradigms. Whereas, their sub-structures or fine structures remain rarely explored despite their potential significance in diagnosing the plasma and magnetic field properties of the star. Such studies in the past have been limited by the sensitivity of radio telescopes. Here we report the inspiring results from the high time-resolution observations of a known flare star AD Leo with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). We detected many radio bursts in the two days of observations with fine structures in the form of numerous millisecond-scale sub-bursts. Sub-bursts on the first day display stripe-like shapes with nearly uniform frequency drift rates, which are possibly stellar analogs to Jovian S-bursts. Sub-bursts on the second day, however, reveal a different blob-like shape with random occurrence patterns and are akin to solar radio spikes. The new observational results suggest that the intense emission from AD Leo is driven by electron cyclotron maser instability which may be related to stellar flares or interactions with a planetary companion. © 2023, CC BY-NC-ND.

关键词： Stars

Imaging a large coronal loop using type U solar radio burst interferometry

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arXiv 2024年

作者： Zhang, Jinge Reid, Hamish A.S. Carley, Eoin Lamy, Laurent Zucca, Pietro Zhang, Peijin Cecconi, Baptiste Mullard Space Science Laboratory University College London RH5 6NT United Kingdom Astronomy & Astrophysics Section Dublin Institute for Advanced Studies DublinD02 XF86 Ireland LESIA Observatoire de Paris Université PSL CNRS Sorbonne Université Université de Paris Meudon France Observatoire de Radioastronomie de Nançay Observatoire de Paris Université PSL CNRS Univ. Orléans Nançay France Aix Marseille Univ CNRS CNES LAM Marseille France ASTRON The Netherlands Institute for Radio Astronomy Oude Hoogeveensedijk 4 Dwingeloo7991 PD Netherlands Center for Solar-Terrestrial Research New Jersey Institute of Technology NewarkNJ United States Cooperative Programs for the Advancement of Earth System Science University Corporation for Atmospheric Research BoulderCO United States

Solar radio U-bursts are generated by electron beams traveling along closed magnetic loops in the solar corona. Low-frequency (☉ in altitude. At this altitude, we found the plasma temperature to be around 1.1 MK, the plasma pressure around 0.20 mdyn,cm−2, and the minimum magnetic field strength around 0.07 G. The similarity in physical properties determined from the image suggests a symmetric loop. The average electron beam velocity on the ascending leg was found to be 0.21 c, while it was 0.14 c on the descending leg. This apparent deceleration is attributed to a decrease in the range of electron energies that resonate with Langmuir waves, likely due to the positive background plasma density gradient along the downward loop leg. Copyright © 2024, The Authors. All rights reserved.

关键词： Electron beams

High Nitrogen Fertilizer Input Enhanced the Microbial Network Complexity in the Paddy Soil

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SSRN

SSRN 2023年

作者： Chen, Yanan Li, Yan Qiu, Tianyi He, Haoran Liu, Ji Duan, Chengjiao Cui, Yongxing Fang, Linchuan The Research Center of Soil and Water Conservation and Ecological Environment Chinese Academy of Sciences Ministry of Education Shaanxi Yangling712100 China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation CAS and MWR Yangling712100 China University of Chinese Academy of Sciences Beijing100049 China Institute of Environment Resource and Soil Fertilizer Zhejiang Academy of Agricultural Sciences Hangzhou310021 China College of Natural Resources and Environment Northwest A&F University Yangling712100 China Hubei Province Key Laboratory for Geographical Process Analysis and Simulation Central China Normal University Wuhan430079 China Department of Ecohydrology Leibniz Institute of Freshwater Ecology and Inland Fisheries Berlin12587 Germany Sino-French Institute for Earth System Science College of Urban and Environmental Sciences Peking University Beijing100871 China Wuhan University of Technology China

Nitrogen (N) fertilization drives the composition and function of soil microbial communities, which are crucial for regulating soil biogeochemical cycling and maintaining ecosystem stability. The influences of N fertilizer on soil microbial composition and diversity have been widely explored, while it is commonly overlooked that ecosystem processes are carried out via complex webs of co-occurrence networks among microbiome members. Here, we examined the effects of five N fertilization levels (0, 135, 180, 225, and 360 kg N ha-1) on microbial co-occurrence networks and key functional taxa such as ammonia-oxidizers in paddy soils. The results showed that N addition altered microbial community composition, which were positively related to soil total N and available phosphorus (P) contents. The abundance of ammonia-oxidizing archaea (AOA) significantly decreased after N addition, whereas ammonia-oxidizing bacteria (AOB) increased in N360 treatment. Compared with low-N group (N0 and N135), the high-N group (N225 and N360) shaped more complex microbial webs and thus improved the stability of the microbial community. Partial least squares path modelling further revealed that N fertilizer had a higher effect on microbial network complexity in the high-N group (0.83) than the low-N group (0.49). Although there were more positive links across all microbial networks, the proportion of negative links significantly increased in the high-N networks, suggesting that excess N addition aggravated the competition among microbial species. Disentangling these interactions between microbial communities and N fertilization advances our understanding of biogeochemical processes in paddy soils and their effects on nutrient supply to rice production. Our findings highlighted that highly N-enriched paddy soils have more stable microbial networks and can better sustain soil ecological functions to cope with the ongoing environmental changes. © 2023, The Authors. All rights reserved.

关键词： Nitrogen fertilizers

Recursive Adaptive Control of Y-Shape space Robot

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Recursive Adaptive Control of Y-Shape Space Robot

第三十八届中国控制会议

作者： Yunpeng Wang Yongchun Xie Beijing Institute of Control Engineering Science and Technology on Space Intelligent Control Laboratory Tianjin Key Laboratory of Microgravity and Hypogravity Environment Simulation Technology

This paper studies the control of a Y-shape space robot, which is a spacecraft mounted with a Y-shape manipulator. The Y-shape manipulator is composed of one main manipulator and two sub-manipulators. By using spatial vector and directed path method, the recursive dynamics model is established. Moreover, the closed form dynamics of the space robot is also deduced. It is assumed that the exact knowledge of the inertia parameters is not available. The adaptive control method is used to deal with this difficulty. In order to improve the computational efficiency, the recursive form of the adaptive controller is also ***, a simulation example is provided to demonstrate the effectiveness of the proposed approach.

关键词： Y-Shape space Robot Recursive Adaptive Control

Observations of Titan’s Stratosphere During Northern Summer: Temperatures, CH3CN and CH3D Abundances

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arXiv 2024年

作者： Thelen, Alexander E. Nixon, Conor A. Cordiner, Martin A. Lellouch, Emmanuel Vinatier, Sandrine Teanby, Nicholas A. Butler, Bryan Charnley, Steven B. Cosentino, Richard G. Kleer, Katherine de Irwin, Patrick G.J. Gurwell, Mark A. Kisiel, Zbigniew Moreno, Raphael Division of Geological and Planetary Sciences California Institute of Technology PasadenaCA91125 United States Solar System Exploration Division NASA Goddard Space Flight Center GreenbeltMD20771 United States Department of Physics Catholic University of America WashingtonDC20064 United States LESIA Observatoire de Paris Université PSL Sorbonne Université Université Paris Cité CNRS Meudon92195 France School of Earth Sciences University of Bristol Bristol United Kingdom National Radio Astronomy Observatory SocorroNM87801 United States Space Telescope Science Institute BaltimoreMD21218 United States Atmospheric Oceanic and Planetary Physics Clarendon Laboratory OxfordOX1 3PU United Kingdom Center for Astrophysics Harvard & Smithsonian CambridgeMA02138 United States Institute of Physics Polish Academy of Sciences Al. Lotników 32/46 Warszawa02-668 Poland

Titan’s atmospheric composition and dynamical state have previously been studied over numerous epochs by both ground- and space-based facilities. However, stratospheric measurements remain sparse during Titan’s northern summer and fall. The lack of seasonal symmetry in observations of Titan’s temperature field and chemical abundances raises questions about the nature of the middle atmosphere’s meridional circulation and evolution over Titan’s 29-yr seasonal cycle that can only be answered through long-term monitoring campaigns. Here, we present maps of Titan’s stratospheric temperature, acetonitrile (or methyl cyanide;CH3CN), and monodeuterated methane (CH3D) abundances following Titan’s northern summer solstice obtained with Band 9 (∼ 0.43 mm) ALMA observations. We find that increasing temperatures towards high-southern latitudes, currently in winter, resemble those observed during Titan’s northern winter by the Cassini mission. Acetonitrile abundances have changed significantly since previous (sub)millimeter observations, and we find that the species is now highly concentrated at high-southern latitudes. The stratospheric CH3D content is found to range between 4–8 ppm in these observations, and we infer the CH4 abundance to vary between ∼ 0.9−1.6% through conversion with previously measured D/H values. A global value of CH4 = 1.15% was retrieved, lending further evidence to the temporal and spatial variability of Titan’s stratospheric methane when compared with previous measurements. Additional observations are required to determine the cause and magnitude of stratospheric enhancements in methane during these poorly understood seasons on Titan. Copyright © 2024, The Authors. All rights reserved.

关键词： Methane

An Ice Age JWST inventory of dense molecular cloud ices

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Nature Astronomy 2023年第4期7卷 431-443页

作者： McClure, M.K. Rocha, W.R.M. Pontoppidan, K.M. Crouzet, N. Chu, L.E.U. Dartois, E. Lamberts, T. Noble, J.A. Pendleton, Y.J. Perotti, G. Qasim, D. Rachid, M.G. Smith, Z.L. Sun, Fengwu Beck, Tracy L. Boogert, A.C.A. Brown, W.A. Caselli, P. Charnley, S.B. Cuppen, Herma M. Dickinson, H. Drozdovskaya, M.N. Egami, E. Erkal, J. Fraser, H. Garrod, R.T. Harsono, D. Ioppolo, S. Jiménez-Serra, I. Jin, M. Jørgensen, J.K. Kristensen, L.E. Lis, D.C. McCoustra, M.R.S. McGuire, Brett A. Melnick, G.J. Öberg, Karin I. Palumbo, M.E. Shimonishi, T. Sturm, J.A. van Dishoeck, E.F. Linnartz, H. Leiden Observatory Leiden University Leiden Netherlands Laboratory for Astrophysics Leiden Observatory Leiden University Leiden Netherlands Space Telescope Science Institute Baltimore MD United States NASA Postdoctoral Program Fellow NASA Ames Research Center Moffett Field CA United States Institut des Sciences Moléculaires d’Orsay CNRS Université Paris-Saclay Orsay France Leiden Institute of Chemistry Gorlaeus Laboratories Leiden University Leiden Netherlands Physique des Interactions Ioniques et Moléculaires CNRS Aix Marseille Université Marseille France Department of Physics University of Central Florida Orlando FL United States Max Planck Institute for Astronomy Heidelberg Germany Southwest Research Institute San Antonio TX United States School of Physical Sciences The Open University Milton Keynes United Kingdom Steward Observatory University of Arizona Tucson AZ United States Institute for Astronomy University of Hawai’i at Manoa Honolulu HI United States Department of Chemistry University of Sussex Brighton United Kingdom Max-Planck-Institut für extraterrestrische Physik Garching bei München Germany Solar System Exploration Division NASA Goddard Space Flight Center Greenbelt MD United States Radboud University Institute for Molecules and Materials Nijmegen Netherlands Center for Space and Habitability Universität Bern Bern Switzerland Departments of Astronomy and Chemistry University of Virginia Charlottesville VA United States Institute of Astronomy Department of Physics National Tsing Hua University Hsinchu Taiwan Center for Interstellar Catalysis Department of Physics and Astronomy Aarhus University Aarhus Denmark Centro de Astrobiología (CAB) CSIC-INTA Torrejón de Ardoz Spain Department of Physics Catholic University of America Washington DC United States Niels Bohr Institute University of Copenhagen Copenhagen Denmark Jet Propulsion Laboratory California Institute of Technology Pasadena CA United States Institute of

Icy grain mantles are the main reservoir of the volatile elements that link chemical processes in dark, interstellar clouds with the formation of planets and the composition of their atmospheres. The initial ice composition is set in the cold, dense parts of molecular clouds, before the onset of star formation. With the exquisite sensitivity of the James Webb space Telescope, this critical stage of ice evolution is now accessible for detailed study. Here we show initial results of the Early Release science programme Ice Age that reveal the rich composition of these dense cloud ices. Weak ice features, including ¹³CO₂, OCN⁻, ¹³CO, OCS and complex organic molecule functional groups, are now detected along two pre-stellar lines of sight. The ¹²CO₂ ice profile indicates modest growth of the icy grains. Column densities of the major and minor ice species indicate that ices contribute between 2% and 19% of the bulk budgets of the key C, O, N and S elements. Our results suggest that the formation of simple and complex molecules could begin early in a water-ice-rich environment. © 2023, The Author(s), under exclusive licence to Springer Nature Limited.

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