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Health effects of fine particles(PM_(2.5)) in ambient air

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Science China(Life Sciences) 2015年第6期58卷 624-626页

作者： HAN YiQun zhu tong State Key Joint Laboratory for Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Center for Environment and Health Peking University

Air pollutants have serious health effects on human beings. The 2010 Global Burden of Disease study reports that each year, ambient particulate matter （PM2.5, particles with aero- dynamic diameter 〈 2.5 micrometer） is causing 3.2 million premature deaths globally, and 1.2 million in China alone. Ambient PM pollution ranked fourth among all risk factors in China.

关键词：环境空气细颗粒物人类健康 PM2.5 空气污染物空气动力学风险因素中国

Reaction Mechanism and Product Branching Ratios of OH+C2H3F Reaction:A Theoretical Study

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Chinese Journal of Chemical Physics 2020年第2期33卷 203-209,I0003页

作者： Chih-Hao Chin tong zhu John Zeng-Hui Zhang School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200062China NYU-ECNU Center for Computational Chemistry at NYU Shanghai Shanghai 200062China Department of Chemistry New York UniversityNew York 10003United States of America

Ab initio CCSD(T)/CBS//B3LYP/6-311G(d,p)calculations of the potential energy surface for possible dissociation channels of HOC2H3F,as well as Rice-Ramsperger-Kassel-Marcus(RRKM)calculations of rate constants,were carried out,in order to predict statistical product branching ratios in dissociation of HOC2H3F at various internal *** most favorable reaction pathway leading to the major CH2CHO+HF products is as the following:OH+C2H3F→i2→TS14→i6→TS9→i3→TS3→CH2CHO+HF,where the rate-determining step is HF elimination from the CO bridging position via TS11,lying above the reactants by 3.8 kcal/*** CH2O+CH2F products can be formed by F atom migration from Cαto Cβposition via TS14,then H migration from O to Cαposition via TS16,and C-C breaking to form the products via TS5,which is 1.8 kcal/mol lower in energy than the reactants,and 4.0 kcal/mol lower than TS11.

关键词： Ab initio Potential energy surface Reaction mechanism Rice-Ramsperger-Kassel-Marcus Branching ratio

Mobius Homogeneous Hypersurfaces with One Simple Principal Curvature in S^n+1

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Acta Mathematica Sinica,English Series 2020年第9期36卷 1001-1013页

作者： Ya Yun CHEN Xiu JI tong zhu LI Department of Mathematics Beijing Institute of TechnologyBeijing 100081P.R.China

Let Mob(S^n+1)denote the Mobius transformation group of S^n+1.A hypersurface f:N^n→S^n+1 is called a Mobius homogeneous hypersurface,if there exists a subgroup G■Mob^(S^n+1)such that the orbit G(p)={Ф(p)Ф∈G}=f(M^n).In this paper,we classify the Mobius homogeneous hypersurfaces in S^n+1 with at most one simple principal curvature up to a M?bius transformation.

关键词： Mobius transformation group isometric transformation group Mobius homogeneous hy-persurfaces homogeneous hypersurfaces

Conditions and Phase Shift of Fluid Resonance in Narrow Gaps of Bottom Mounted Caissons

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China Ocean Engineering 2017年第6期31卷 724-735页

作者： zhu Da-tong WANG Xing-gang LIU Qing-jun Jiao zhuan Research Center Southeast University Nanjing 210018 China Nanjing Hydraulic Research Institute Nanjing 210029 China Key Laboratory of Port Waterway and Sedimentation Engineering of the Ministry of Transport Nanjing 210029 China College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China

This paper studies the viscid and inviscid fluid resonance in gaps of bottom mounted caissons onthe basis of the plane wave hypothesis and full wave model, The theoretical analysis and the numerical results demonstrate that the condition for the appearance of fluid resonance in narrow gaps is kh=（2n＋1）π （n=0, 1, 2, 3 ）, rather than kh=nn （n=0, 1, 2, 3, ...）; the transmission peaks in viscid fluid are related to the resonance peaks in the gaps. k and h stand for the wave number and the gap length. The combination of the plane wave hypothesis or the full wave model with the local viscosity model can accurately determine the heights and the locations of the resonance peaks. The upper bound for the appearance of fluid resonance in gaps is 2b/L〈l （2b, grating constant; L, wave length） and the lower bound is h/b〈~ l. The main reason for the phase shift of the resonance peaks is the inductive factors. The number of resonance peaks in the spectrum curve is dependent on the ratio of the gap length to the grating constant. The heights and the positions of the resonance peaks predicted by the present models agree well with the experimental data.

关键词： gap resonance phase shift of resonance peak fluid local viscosity model plane wave hypothesis full wavemodel bottom mounted caissons

Discovery of emerging organic pollutants in the atmosphere through an omics approach

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Frontiers of Environmental Science & Engineering 2023年第4期17卷 71-81页

作者： Zhen Cheng Xinghua Qiu Xiaodi Shi Xing Jiang tong zhu State Key Joint Laboratory for Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringCenter for Environment and HealthPeking UniversityBeijing 100871China

Ambient air pollution,containing numerous known and hitherto unknown compounds,is a major risk factor for public *** discovery of harmful components is the prerequisite for pollution control;however,this raises a great challenge on recognizing previously unknown *** we systematically review the analytical techniques on air pollution in the framework of an omics approach,with a brief introduction on sample preparation and analysis,and in more detail,compounds prioritization and *** high-resolution mass spectrometry(HRMS,typically coupled with chromatography),the complicated environmental matrix can be digitalized into“fullcomponent”data.A key step to discover emerging compounds is the prioritization of compounds from massive *** fingerprints,suspect lists and biological effects are the most vital untargeted strategies for comprehensively screening critical and hazardous ***,compressed data of compounds can be identified at various confidence levels according to exact mass and the derived molecular formula,MS libraries,and authentic *** an omics approach on full-component data provides a paradigm for discovering emerging air pollutants;nonetheless,new technological advancements of instruments and databases are warranted for further tracking the environmental behaviors,hence to evaluate the health risk of key pollutants.

关键词： Air pollution Emerging pollutants Full-component High-resolution mass spectrometry Omics approach

Effect of the Structure Parameters of a Low Swirler on Premixed Characteristics

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Journal of Thermal Science 2022年第1期31卷 207-213页

作者： SHEN Siyuan SONG Xiuyang ZONG Chao JI Chenzhen zhu tong School of Mechanical Engineering Tongji UniversityShanghai 201804China

Combustion with lean premixed and low swirl is an effective way of flame *** can improve the flame stability and reduce NOX *** this kind of combustion,one of the most important issues is fuel/air premixed *** the structure parameters influence that issue is figured out through numerical *** structure parameters concerned in the study are as *** are shape of blades,number of blades,location and shape of gas *** influences of them are analysed with comprehensive consideration of many *** the same light shading rate and stagger angle,the axial swirler with curved blades has worse premixed uniformity and lower pressure loss than the one with straight *** the same structure of each blade,the decrease of the quantity of blades does influence the pressure loss,while the quantity of gas jets changes *** it has little effect on premixed uniformity in a certain ***,more blades make contribution to better premixed *** the total flow area is the same,the axial and circumferential positions of the fuel jets also greatly influence the premixing *** the fuel jets are upstream the blades and locate at middle of the vanes,the premixing performance is the ***,the jet direction of the fuel jets is a very important influencing factor of the premixing *** the fuel jet direction is oblique downward at an angle of 30°to the horizontal,the premixing effect is better than the horizontal outflow,which is better than the oblique upward structure.

关键词： micro gas turbine low swirler premixed characteristics numerical simulation

Evaluation of genotoxicity of combined soil pollution by cadmium and imidacloprid

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Science China(Life Sciences) 2005年第Z1期48卷 7-13页

作者： LIN Aijun zhu Yongguan tong Yiping Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Cadmium (Cd) is one of the important pollutants of soil and the genotoxicity of Cd-contaminated soil was studied in combination with imidacloprid. The single cell gel electro-phoresis or comet assay was used to quantify DNA strand breaks as a measure of DNA damage induced by Cd and imidacloprid contamination in soil. The soil was artificially contaminated by Cd (0.0, 0.2, 0.5, 1.0, 2.0 mg·kg-1 dry soil) or Cd (0.0, 0.2, 0.5, 1.0, 2.0 mg·kg-1 dry soil) and imidacloprid (0.5 mg-kg^1 dry soil). Roots of Vicia faba were exposed to the contaminated soil for 2 h at 25℃ and were used in the comet assay. DNA damage was measured as the values of percentage of nuclei with tails, tail length, tail DNA, tail moment (TM), and Olive tail moment (OTM). DNA damages of root tips of Vicia faba increased after Cd treatment and there were dose-related increases in DNA damage measured as these parameters. However, the addition of imidacloprid further increased the DNA damage. These data confirmed the genotoxic effect of Cd to plants, and that the combined pollution with imidacloprid can enhance the genotoxicity of Cd.

关键词： atrazine, imidacloprid, mixture pollution, genotoxicity, comet assay.

Organochlorine pesticides in fresh-fallen snow on East Rongbuk Glacier of *** (Everest)

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Science China Earth Sciences 2007年第7期50卷 1097-1102页

作者： WANG Feng zhu tong XU BaiQing KANG ShiChang State Key Joint Laboratory for Environmental Simulation&Pollution Control College of Environmental SciencesPeking UniversityBeijing 100871China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100085China

During a field campaign in April 2005,fresh-fallen snow samples were collected on the East Rongbuk Glacier of the Mt. Qomolangma at four altitudes (6500 m,6300 m,6100 m and 5900 m),to study the role of Mt. Qomolangma as "cold-traps" for Persistent Organic Pollutants. From these snow samples col-lected at the highest-altitude,organochlorine pesticides (OCPs):HCB,p,p′-DDT and p,p′-DDD were detected,with the concentrations in the ranges of 44―72 pg/L,401―1560 pg/L,and 20―80 pg/L,re-spectively. The concentration of o,p′-DDT was around the method detection limit. Analysis of backward trajectories showed that the detected compounds came from the north of India,suggesting that DDTs detected in the snow were possibly originated from new emissions in this area. Relationships between the concentrations of OCPs in snow samples and the sampling altitudes were discussed. The altitudes had no obvious effect on HCB concentrations in the fresh-fallen snow,while increases in the concen-trations of p,p′-DDT and p,p′-DDD with increasing altitude were found,which was reversed compared to the trends observed in North America. Three factors likely resulted in this trend: (1) the properties of the target compounds; (2) the low temperatures at high altitudes; and (3) the location of the mountain sampling sites relative to their sources.

关键词： Mt. Qomolangma (Everest) Tibet organochlorine pesticides snow long-range transport

Health-oriented strategies are needed to optimize China’s 2025 clean air action plan

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Science Bulletin 2024年第13期69卷 2007-2008页

作者： Tao Xue Ning Kang Wei Wan tong zhu Institute of Reproductive and Child Health/National Health Commission Key Laboratory of Reproductive Health and Department of Epidemiology and Biostatistics/Ministry of Education Key Laboratory of Epidemiology of Major Diseases(PKU) School of Public HealthPeking University Health Science CentreBeijing 100191China State Environmental Protection Key Laboratory of Atmospheric Exposure and Health Risk Management Center for Environment and HealthPeking UniversityBeijing 100871China Advanced Institute of Information Technology Peking UniversityHangzhou 311215China Clean Air Asia Beijing 100600China College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China

Recently,China’s State Council issued the Continuous Improvement of Air Quality Action Plan(hereafter,the third action plan),which follows the Air Pollution Prevention and Control Action Plan(2013–2017)(hereafter,the first action plan)and the Three-Year Action Plan for Winning the Blue Sky Defense Battle(2018–2020)(hereafter the second action plan).The first two action plans yielded nationwide health benefits[1–3],from improving lung function[4]to saving medical expenditures[5].Based on our previous estimates[6],due to reductions in the fine particulate matter(PM2.5)level,implementation of the first and second action plans was expected to increase life expectancy by 2.11 and 3.68 months.

关键词： action hereafter nationwide