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Characteristics of ozone pollution and the sensitivity to precursors during early summer in central plain, China

Journal of Environmental Sciences 2021年第1期33卷 354-368页

作者： Yasong Li Shasha Yin Shijie YU Ling Bai Xudong Wang Xuan Lu shuangliang ma Research Institute of Environmental Science College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhou450001China Henan Enuironmental Monitoring Center Zhengzhou450004China

In this study,we conducted an observation experiment from may 1 to June 30,2018 in Zhengzhou,a major city in central China,where ground ozone(O3)pollution has become serious in recent years.The concentrations of O3 and its precursors,as well as H2O_(2) and meteorological data were obtained from the urban site(Yanchang,YC),suburban(Zhengzhou University,ZZU)and background sites(Ganglishuiku,GLSK).Result showed that the rates of O3 concentration exceeded Chinese National Air Quality Standard GradeⅡ(93.3 ppbv)were 59.0%,52.5%,and 55.7%at the above three sites with good consistency,respectively,indicating that O3 pollution is a regional problem in Zhengzhou.The daily peak O3 appeared at 15:00-16:00,which was opposite to VOCs,NOx,and CO and consistent with H2O_(2).The exhaustive statistical analysis of meteorological factors and chemical effects on O3 formation at YC was advanced.The high concentration of precursors,high temperature,low relative humidity,and moderately high wind speed together with the wind direction dominated by south and southeast wind contribute to urban O3 episodes in Zhengzhou.O3 formation analysis showed that reactive alkenes such as isoprene and cis-2-butene contributed most to O3 formation.The VOCs/NOx ratio and smog production model were used to determine O3-VOC-NOx sensitivity.The O3 formation in Zhengzhou during early summer was mainly under VOC-limited and transition regions alternately,which implies that the simultaneous emission reduction of alkenes and NOx is effective in reducing O3 pollution in Zhengzhou.

关键词： H2O_(2) Meteorological influences Ozone formation potential Smog production model O3-VOC-NOx

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Light absorption properties and potential sources of brown carbon in Fenwei Plain during winter 2018–2019

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Journal of Environmental Sciences 2021年第4期33卷 53-63页

作者： Wenyu Zhang Weigang Wang Jie Li shuangliang ma Chaofan Lian Kun Li Bo Shi Mingyuan Liu Yanyu Li QingQing Wang Yele Sun Shengrui Tong maofa Ge State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular Sciences(BNLMS)Chemistry Academy of Sciences Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Henan Environmental Monitoring Center Station Zhengzhou 450000China Laboratory of Atmospheric Chemistry Paul Scherrer Institute(PSI)Villigen 5232Switzerland Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Department of Clinical Research Central Hospital Affiliated to Shandong First Medical UniversityJinan 250013China

A distinctive kind of organic carbon aerosol that could absorb ultraviolet-visible radiation is called brown carbon(Br C),which has an important positive influence on radiative budget and climate change.In this work,we reported the absorption properties and potential source of Br C based on a seven-wavelength aethalometer in the winter of 2018–2019 at an urban site of Sanmenxia in Fenwei Plain in central China.Specifically,the mean value of Br C absorption coefficient was 59.6±36.0 Mm^(-1) at 370 nm and contributed 37.7%to total absorption,which made a significant impact on visibility and regional environment.Absorption coefficients of Br C showed double-peak pattern,and Br C had shown small fluctuations under haze days compared with clean days.As for the sources of Br C,Br C absorption coefficients expressed strong correlations with element carbon aerosols and primary organic carbon aerosols,indicating that most of Br C originated from primary emissions.The linear correlations between trace metal elements(K,As,Fe,Mn,Zn,and Pb)and Br C absorption coefficients further referred that the major sources of Br C were primary emissions,like coal burning,biomass burning,and vehicle emissions.The moderate relationship between Br C absorption coefficients and secondary organic aerosols suggested that secondary production of Br C also played an important role.The 120 hr backward air mass trajectories analysis and concentration-weighted trajectories analysis were also used to investigate potential sources of Br C in and around this area,which inferred most parts of Br C were derived from local emissions.

关键词： Brown carbon Light absorption Potential source analysis Fenwei Plain

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2022北京冬奥会管控下新乡市农村地区PM_(2.5)中重金属及生态风险变化特征

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环境科学学报 2024年第1期44卷 47-61页

作者：王光奇王玲玲马双良王一克赵文鹏马琳李红亮黄皓旻范丽雅叶代启华南理工大学环境与能源学院广州510006 河南省生态环境监测和安全中心郑州450000 河南省新乡生态环境监测中心新乡453000 挥发性有机物污染治理技术与装备国家工程实验室广州510006 广东省大气环境与污染控制重点实验室广州510006 广东省环境风险防控与应急处置工程技术研究中心广州510006

细颗粒物(PM_(2.5))中的重金属威胁着人体健康和生态环境.本文基于2022年北京冬奥会期间新乡市采取的不同污染管控措施,于2022年1月20日—2月20日在新乡市一个农村站点对PM_(2.5)进行逐小时采样,并检测了其中20种重金属元素的浓度,研究... 详细信息

细颗粒物(PM_(2.5))中的重金属威胁着人体健康和生态环境.本文基于2022年北京冬奥会期间新乡市采取的不同污染管控措施,于2022年1月20日—2月20日在新乡市一个农村站点对PM_(2.5)进行逐小时采样,并检测了其中20种重金属元素的浓度,研究了不同管控阶段(管控前阶段P1、严格管控阶段P2、宽松管控阶段P3)新乡市农村地区重金属污染特征及其与管控措施的关系.结果表明:严格管控期间Zn、Pb、Mn、As、Se、Hg、Cr和Ni的浓度明显下降,降幅分别为50.2%、29.3%、39.1%、67.9%、33.4%、27.7%、51.9%和32.2%,其中,As和Cr的污染程度(I_(geo))显著降低,降幅分别为34.3%和27.8%,其余元素的I_(geo)仅轻微降低或未降低.宽松管控期间Mn、Cr、Ni的浓度和I_(geo)均显著上升,浓度分别上升49.8%、26.3%和17.4%,I_(geo)分别上升27.9%、21.1%和22.5%.日变化分析表明,严格管控措施下K、Ca、Pb和As的日变化特征与其他时段有所不同,其余元素则无显著差异.此外,严格管控期间气象条件对所测元素的作用也与其他时段不同,表现得更为复杂.新乡市农村地区重金属的潜在生态风险等级为极高(生态风险综合指数>1200),其中,风险最高的元素为Cd、Se、Pb、As(生态风险指数:64~12714).污染程度和潜在生态风险均较高的4种元素为Cd、As、Pb、Se,其浓度权重轨迹(CWT)结果显示Cd的主要潜在源区在山东中南部,而其余3种元素的潜在源区则集中在河北东南部,且不同阶段的潜在源区有一定差异.

关键词：北京冬奥会新乡农村 PM_(2.5) 重金属生态风险潜在源

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VOC emitted by biopharmaceutical industries:Source profiles,health risks,and secondary pollution

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Journal of Environmental Sciences 2024年第1期135卷 570-584页

作者： Jiawei ma Lin Li State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China National Engineering Laboratory for VOCs Pollution Control material&Technology University of Chinese Academy of SciencesBeijing 101408China

The biopharmaceutical industry contributes substantially to volatile organic compounds(VOCs)emissions,causing growing concerns and social developmental conflicts.This study conducted an on-site investigation of the process-based emission of VOCs from three biopharmaceutical enterprises.In the workshops of the three enterprises,26 VOCs were detected,which could be sorted into 4 classes:hydrocarbons,aromatic hydrocarbons,oxygen-containing compounds,and nitrogen-containing compounds.Ketones were the main components of waste gases,accounting for 44.13%-77.85%of the overall VOCs.Process-based source profiles were compiled for each process unit,with the fermentation and extraction units of tiamulin fumarate being the main source of VOC emissions.Dimethyl heptanone,vinyl acetate,diethylamine,propylene glycol methyl ether(PGME),and benzene were screened as priority pollutants through a fuzzy comprehensive evaluation system.Ground level concentration simulation results of the Gauss plume diffusion model demonstrated that the diffusivity of VOCs in the atmosphere was relatively high,indicating potential non-carcinogenic and carcinogenic risks 1.5-2 km downwind.Furthermore,the process-based formation potentials of ozone and secondary organic aerosols(SOAs)were determined and indicated that N-methyl-2-pyrrolidone,dimethyl heptanone,and PGME should be preferentially controlled to reduce the ozone formation potential,whereas the control of benzene and chlorobenzene should be prioritized to reduce the generation of SOAs.Our results provide a basis for understanding the characteristics of VOC emission by biopharmaceutical industries and their diffusion,potentially allowing the development of measures to reduce health risks and secondary pollution.

关键词： Biopharmaceutical Volatile organic compound Priority pollutant Exposure risk Secondary pollution

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Nuclear phylogenomics of angiosperms and insights into their relationships and evolution

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Journal of Integrative Plant Biology 2024年第3期66卷 546-578页

作者： Guojin Zhang Hong ma College of Life Sciences Hunan Normal UniversityChangsha 410081China Department of Biology 510 Mueller LaboratoryHuck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPA 16802USA

Angiosperms(flowering plants) are by far the most diverse land plant group with over 300,000 species. The sudden appearance of diverse angiosperms in the fossil record was referred to by Darwin as the “abominable mystery,”hence contributing to the heightened interest in angiosperm evolution. Angiosperms display wide ranges of morphological, physiological,and ecological characters, some of which have probably influenced their species richness. The evolutionary analyses of these characteristics help to address questions of angiosperm diversification and require well resolved phylogeny. Following the great successes of phylogenetic analyses using plastid sequences,dozens to thousands of nuclear genes from next-generation sequencing have been used in angiosperm phylogenomic analyses, providing well resolved phylogenies and new insights into the evolution of angiosperms. In this review we focus on recent nuclear phylogenomic analyses of large angiosperm clades, orders, families,and subdivisions of some families and provide a summarized Nuclear Phylogenetic Tree of Angiosperm Families. The newly established nuclear phylogenetic relationships are highlighted and compared with previous phylogenetic results. The sequenced genomes of Amborella,Nymphaea, Chloranthus, Ceratophyllum, and species of monocots, magnoliids, and basal eudicots, have facilitated the phylogenomics of relationships among five major angiosperms clades. All but one of the 64 angiosperm orders were included in nuclear phylogenomics with well resolved relationships except the placements of several orders. Most families have been included with robust and highly supported placements, especially for relationships within several large and important orders and families.Additionally, we examine the divergence time estimation and biogeographic analyses of angiosperm on the basis of the nuclear phylogenomic frameworks and discuss the differences compared with previous analyses. Furthermore,we discuss the implications of nuclear phylogenomic analyses on ancestral

关键词： angiosperms evolution flowering plants nuclear gene phylogenomics phylogeny

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Uniform decomposition of velocity gradient tensor

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Journal of Hydrodynamics 2024年第1期36卷 24-34页

作者： Chenxi ma Chaoqun Liu Department of mathematics University of Texas at ArlingtonArlingtonTXUSA

In this paper,the principal decomposition of the velocity gradient tensor[∇v]is discussed in 3 cases based on the discriminant∆:∆0 with 3 distinct real eigen values,and∆=0 with 1 or 2 distinct real eigen values.The velocity gradient tensor can also be classified as rotation point,which can be decomposed into three parts,i.e.,rotation[R],shear[S]and stretching/compression[SC],and non-rotation point,we defined a new resistance term[L],and the tensor can be decomposed into three parts,i.e.,resistance[L],shear[S]and stretching/compression[SC].Example matric are also displayed to demonstrate the new decomposition.Connections of principal decomposition between 3 different cases,and between Resistance and Liutex will also be discussed.

关键词： Velocity gradient Liutex resistance fluid kinematics

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Copper slag assisted coke reduction of phosphogypsum for sulphur dioxide preparation

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Chinese Journal of Chemical Engineering 2024年第1期65卷 43-53页

作者： Dong ma Qinhui Wang State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China

The reduction of phosphogypsum(PG)to lime slag and SO_(2)using coke can effectively alleviate the environmental problems caused by PG.However,the PG decomposition temperature remains high and the product yield remains poor.By adding additives,the decomposition temperature can be further reduced and PG decomposition rate and product yield can be improved.However,the use of current additives such as Fe_(2)O_(3)and SiO_(2)brings the problem of increasing economic cost.Therefore,it is proposed to use solid waste copper slag(CS)as a new additive to reduce PG to prepare SO2,which can reduce the cost and meet the environmental benefits at the same time.The effects of proportion,temperature and thermostatic time on PG decomposition are investigated by experimental and kinetic analysis combined with FactSage thermodynamic calculations to optimize the roasting conditions.Finally,the reaction mechanism is proposed.It is found that adding CS to the coke and PG system can increase the rate of PG decomposition and SO_(2)yield while lowering the PG decomposition temperature.For example,when the CS/PG mass ratio increases from 0 to 1,PG decomposition rate increases from 83.38%to 99.35%,SO_(2)yield increases from 78.62%to 96.81%,and PG decomposition temperature decreases from 992.4℃to 949.6℃.The optimal reaction parameters are CS/PG mass ratio of 1,Coke/PG mass ratio of 0.06 at 1100℃for 20 min with 99.35%PG decomposition rate and 96.81%SO_(2) yield.The process proceeds according to the following reactions:2CaSO_(4)+ 0.7C + 0.8Fe_(2)SiO_(4)→0.8Ca_(2)SiO_(4)+ 0.2Ca_(2)Fe_(2)O_(5)+ 0.4Fe_(3)O_(4)+2SO_(2)+ 0.7CO_(2)Finally,a process for decomposing PG with coke and CS is proposed.

关键词： Phosphogypsum Sulfur dioxide Copper slag Fluidized-bed Reduction Waste treatment

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A review of recent advances in the effects of surface and interface properties on marine propellers

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Friction 2024年第2期12卷 185-214页

作者： manfu ZHU Liran ma State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

marine propellers are important propulsion devices for both surface ships and underwater vehicles.Increasingly severe environmental problems have required further performance enhancement for propellers.Nowadays,traditional methods to improve propeller performances through geometrical and structural optimizations have been extensively investigated,while the underlying mechanisms of the effects of surface and interface properties on marine propellers are still far from being fully understood.This paper presented a comprehensive review of recent advances in the effects of surface and interface properties,such as surface roughness and surface wettability,on marine propellers with an emphasis on the significant improvements in both hydrodynamic and cavitation performances,hoping to arouse more in-depth investigations in the field of surface/interface science and technologies on marine propellers,and also promote the state-of-the-art technologies,such as superlubricity technology,into practical applications.

关键词： marine propellers hydrodynamics cavitation surface roughness surface wettability

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Catalysis by subsurface metal atoms in Al(001) through electron transfer

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National Science Review 2024年第4期11卷 12-13页

作者： Bo Sun Ding ma Beijing National Laboratory for Molecular Science New Cornerstone Science Laboratory College of Chemistry and Molecular Engineering Peking University

Heterogeneous catalysis plays a crucial role in the chemical industry, which has evolved from the investigation of chemisorption to an electronic structure[1]. Diverse strategies, such as alloying,doping, and confining, have been applied to enhance the catalytic properties of active sites through electronic modulation. The electron transfer between active sites and substrates profoundly influences catalytic activity [2].

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Tuning Surface Molecular Design of Porous Carbon for Blue Energy Harvesting

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Research 2024年第1期2023卷 651-662页

作者： Jian Yu Zhong-Lin Wang Tianwei ma Department of Civil and Environmental Engineering University of Hawaii at MānoaHonoluluHI 96822USA Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Engineering Texas A&M University-Corpus ChristiCorpus ChristiTX 78412USA

Capacitive mixing is a promising blue energy technology due to its membrane-free electricity generation and long electrode life cycle.However,because of limited performance,existing systems do not lend themselves to practical implementation.Although it is a crucial factor directly influencing electrode behavior,surface chemistry has largely been overlooked in capacitive mixing.Here,we show that manipulating surface functionalization alone can tune the responses of electrodes to produce a high voltage rise without altering the pore structure of the electrodes.Our findings reveal that the spontaneous electrode potential of a surface-modified carbon electrode shifts negatively proportional to the surface charge due to the surface groups,which explains why and how manipulating the surface chemistry can improve the power generation capacity.

关键词： electrode Porous mixing

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