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Volatile organic compounds in wintertime North China Plain:Insights from measurements of proton transfer reaction time-of-flight mass spectrometer(PTR-ToF-MS)

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Journal of Environmental Sciences 2022年第4期34卷 98-114页

作者： Xianjun He Bin Yuan Caihong Wu Sihang Wang Chaomin Wang Yibo Huangfu Jipeng Qi Nan Ma Wanyun Xu Ming Wang wentai chen Hang Su Yafang cheng Min Shao Institute for Environmental and Climate Research Jinan UniversityGuangzhou 511443China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou 511443China State Key Laboratory of Severe Weather&Key Laboratory for Atmospheric Chemistry of China Meteorology Administration Chinese Academy of Meteorological SciencesBeijing 100081China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution ControlSchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjing 210044China Nanjing Intelligent Environmental Science and Technology Co. Ltd.Nanjing 211800China Max Planck Institute for Chemistry Mainz 55128Germany

The characteristics of wintertime volatile organic compounds(VOCs)in the North China Plain(NCP)region are complicated and remain obscure.VOC measurements were conducted by a proton transfer reaction time-of-flight mass spectrometer(PTR-ToF-MS)at a rural site in the NCP from November to December 2018.Uncalibrated ions measured by PTRToF-MS were quantified and the overall VOC compositions were investigated by combining the measurements of PTR-ToF-MS and gas chromatography-mass spectrometer/flame ionization detector(GC-MS/FID).The measurement showed that although atmospheric VOCs concentrations are often dominated by primary emissions,the secondary formation of oxygenated VOCs(OVOCs)is non-negligible in the wintertime,i.e.,OVOCs accounts for 42%±7%in the total VOCs(151.3±75.6 ppbV).We demonstrated that PTR-MS measurements for isoprene are substantially overestimated due to the interferences of cycloalkanes.The chemical changes of organic carbon in a pollution accumulation period were investigated,which suggests an essential role of fragmentation reactions for large,chemically reduced compounds during the heavy-polluted stage in wintertime pollution.The changes of emission ratios of VOCs between winter 2011 and winter 2018 in the NCP support the positive effect of“coal to gas”strategies in curbing air pollutants.The high abundances of some key species(e.***.oxygenated aromatics)indicate the strong emissions of coal combustion in wintertime of NCP.The ratio of naphthalene to C8 aromatics was proposed as a potential indicator of the influence of coal combustion on VOCs.

关键词： North China Plain Volatile organic compound Wintertime PTR-ToF-MS

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Investigation of carbonyl compound sources at a rural site in the Yangtze River Delta region of China

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Journal of Environmental Sciences 2015年第2期27卷 128-136页

作者： Ming Wang wentai chen Min Shao Sihua Lu Limin Zeng Min Hu State Joint Key Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University

Carbonyl compounds are important intermediates in atmospheric photochemistry, but their primary sources are still not understood well. In this work, carbonyls, hydrocarbons,and alkyl nitrates were continuously measured during November 2011 at a rural site in the Yangtze River Delta region of China. Mixing ratios of carbonyls and hydrocarbons showed large fluctuations during the entire measurement. The average level for total measured volatile organic compounds during the pollution episode from 25 th to 27 th November, 2011 was 91.6 ppb, about 7 times the value for the clean period of 7th–8th, November, 2011. To preliminarily identify toluene sources at this site, the emission ratio of toluene to benzene（T/B） during the pollution episode was determined based on photochemical ages derived from the relationship of alkyl nitrates to their parent alkanes. The calculated T/B was5.8 ppb/ppb, significantly higher than the values of 0.2–1.7 ppb/ppb for vehicular exhaust and other combustion sources, indicating the dominant influence of industrial emissions on ambient toluene. The contributions of industrial sources to ambient carbonyls were then calculated using a multiple linear regression fit model that used toluene and alkyl nitrates as respective tracers for industrial emission and secondary production. During the pollution episode, 18.5%, 69.0%, and 52.9% of measured formaldehyde, acetaldehyde, and acetone were considered to be attributable to industrial emissions. The emission ratios relative to toluene for formaldehyde, acetaldehyde, and acetone were determined to be 0.10, 0.20 and0.40 ppb/ppb, respectively. More research on industrial carbonyl emission characteristics is needed to understand carbonyl sources better.

关键词： Carbonyl compounds Source apportionment Industrial emission Yangtze River Delta

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Ozone pollution characteristics and sensitivity analysis using an observation-based model in Nanjing,Yangtze River Delta Region of China

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Journal of Environmental Sciences 2020年第7期32卷 13-22页

作者： Ming Wang wentai chen Lin Zhang Wei Qin Yong Zhang Xiangzhi Zhang Xin Xie Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution ControlSchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjingJiangsuChina Jiangsu Environmental Monitoring Center NanjingJiangsuChina Department of Ecology and Environment of Jiangsu Province NanjingJiangsuChina Nanjing Environmental Monitoring Center Jiangsu ProvinceNanjingJiangsuChina

Ground-level ozone(O3)has become a critical pollutant impeding air quality improvement in Yangtze River Delta region of China.In this study,we present O3 pollution characteristics based on one-year online measurements during 2016 at an urban site in Nanjing,Jiangsu Province.Then,the sensitivity of O3 to its precursors during 2 O3 pollution episodes in August was analyzed using a box model based on observation(OBM).The relative incremental reactivity(RIR)of hydrocarbons was larger than other precursors,suggesting that hydrocarbons played the dominant role in O3 formation.The RIR values for NOX ranged from–0.41%/%to 0.19%/%.The O3 sensitivity was also analyzed based on relationship of simulated O3 production rates with reductions of VOC and NOX derived from scenario analyses.Simulation results illustrate that O3 formation was between VOCs-limited and transition regime.Xylenes and light alkenes were found to be key species in O3 formation according to RIR values,and their sources were determined using the Positive Matrix Factorization(PMF)model.Paints and solvent use was the largest contributor to xylenes(54%),while petrochemical industry was the most important source to propene(82%).Discussions on VOCs and NOX reduction schemes suggest that the 5%O3 control goal can be achieved by reducing VOCs by 20%.To obtain 10%O3 control goal,VOCs need to be reduced by 30%with VOCs/NOX larger than 3:1.

关键词： Ozone sensitivity OBM VOCs Yangtze River Delta

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Emission factors of gaseous carbonaceous species from residential combustion of coal and crop residue briquettes

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Frontiers of Environmental Science & Engineering 2013年第1期7卷 66-76页

作者： Qin WANG Chunmei GENG Sihua LU wentai chen Min SHAO State Joint Key Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China Chinese Research Academy of Environmental Sciences Beijing 100012 China

Experiments were performed to measure the emission factors ( s) of gaseous carbonaceous species, such as CO , CO, CH , and non-methane volatile organic compounds (NMVOCs), from the combustion of five types of coal of varying organic maturity and two types of biomass briquettes under residential burning conditions. Samples were collected in stainless steel canisters and 2,4-dinitrophenylhydrazine (DNPH) cartridges and were analyzed by GC–FID/MS and HPLC, respectively. The s from crop residue briquette burning were generally higher than those from coals, with the exception of CO . The dominant NMVOC species identified in coal smoke were carbonyls (41.7%), followed by C2 unsaturated hydrocarbons (29.1%) and aromatics (12.1%), while C2 unsaturated hydrocarbons were the dominant species (68.9%) emitted from the combustion of crop residue briquettes, followed by aromatics (14.4%). A comparison of burning normal crop residues in stoves and the open field indicated that briquettes emitted a larger proportion of ethene and acetylene. Both combustion efficiency and coal organic maturity had a significant impact on NMVOC s from burning coal: NMVOC emissions increased with increasing coal organic maturity but decreased as the combustion efficiency improved. Emissions from the combustion of crop residue briquettes from stoves occurred mainly during the smoldering process, with low combustion efficiency. Therefore, an improved stove design to allow higher combustion efficiency would be beneficial for reducing emissions of carbonaceous air pollutants.

关键词： residential combustion coal crop residue briquette emission factors gaseous carbonaceous species

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紫外超短脉冲激光硅表面微槽刻蚀研究

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应用激光 2024年第4期44卷 15-20页

作者：陈海鹏王浩欧阳文泰上海市激光技术研究所有限公司上海200233 上海激光智能制造工程技术研究中心上海200233 中国科学院宁波材料技术与工程研究所浙江宁波315201

硅基微流控板已经被广泛应用于微流控领域,超短脉冲激光技术提供了一种灵活、精确的硅表面微槽制造方法。为降低激光作用过程中对硅材料的热影响,使用脉冲宽度为12 ps的紫外超短脉冲激光进行刻蚀,分析不同激光功率和激光扫描次数等激光... 详细信息

硅基微流控板已经被广泛应用于微流控领域,超短脉冲激光技术提供了一种灵活、精确的硅表面微槽制造方法。为降低激光作用过程中对硅材料的热影响,使用脉冲宽度为12 ps的紫外超短脉冲激光进行刻蚀,分析不同激光功率和激光扫描次数等激光刻蚀参数对微槽的影响。在激光共聚焦显微镜的帮助下,研究不同激光参数对微槽深度变化以及微槽底部粗糙度的影响,结果显示增加激光功率和激光扫描次数能有效提升微槽深度,并且也会增加微槽底部的粗糙度。

关键词：超短脉冲激光激光刻蚀微槽硅片

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“表里如一”还是“口是心非”:CEO学术经历与食品安全信息披露质量

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江苏大学学报（社会科学版） 2024年第1期26卷 94-108页

作者：毕文泰田瑞陈素云河南农业大学经济与管理学院

企业管理者是食品安全信息披露决策的主体,其特征如何影响食品安全信息质量值得关注。以中国A股食品类上市公司为样本,采用内容分析法构建食品安全信息披露指标体系,可探究出CEO学术经历与食品安全信息披露质量之间的关系。结果表明:CE... 详细信息

企业管理者是食品安全信息披露决策的主体,其特征如何影响食品安全信息质量值得关注。以中国A股食品类上市公司为样本,采用内容分析法构建食品安全信息披露指标体系,可探究出CEO学术经历与食品安全信息披露质量之间的关系。结果表明:CEO学术经历能显著提高食品安全信息披露质量,具有学术经历的CEO更倾向于披露战略理念而非实际行动。另外,制度环境和声誉压力在CEO学术经历和食品安全信息披露之间起到了调节作用,良好的制度环境更有利于CEO学术经历对食品安全信息披露质量的提升;媒体负面报道对企业造成的压力越大,学者型CEO披露食品安全信息越积极。从高管学术经历这一微观层面扩展食品安全信息披露领域的文献研究,对于优化食品类企业管理者结构和选聘机制,提升公司食品安全信息披露质量可提供理论指导和经验证据。

关键词：学术经历食品安全信息披露声誉压力高层梯队理论制度环境

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Carbon Nitride Quantum Dots:A Novel Fluorescent Probe for Non-Enzymatic Hydrogen Peroxide and Mercury Detection

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Journal of Ocean University of China 2023年第6期22卷 1572-1582页

作者： chen Lei LI Quan WANG Xing WANG wentai WANG Lisha Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationCollege of Chemistry and Chemical EngineeringOcean University of ChinaQingdao 266100China

The mercury species in the ocean(MeHg,Hg^(2+))will be enriched in marine organisms and threaten human health through the food chain.While the excessive H_(2)O_(2)in the metabolic process will produce hydroxyl radicals and accelerate the aging of human cells,causing a series of diseases.Hence,the cost-effective and rapid detection of mercury and H_(2)O_(2)is of urgent requirement and significance.Here,we synthesized emerging graphitic carbon nitride quantum dots(g-CNQDs)with high fluorescence quantum yield(FLQY)of 42.69%via a bottom-up strategy by a facile one-step hydrothermal method.The g-CNQDs can detect the H_(2)O_(2)and Hg^(2+)through the fluorescence quenching effect between g-CNQDs and detected substances.With the presence of KI,g-CNQDs show concentration-dependent fluorescence toward H_(2)O_(2),with a wide detection range of 1–1000μmolL^(-1)and a low detection limit of 0.23μmolL^(-1).The g-CNQDs also show sensitivity toward Hg^(2+)with a detection range of 0–0.1μmolL^(-1)and a detection limit of 0.038μmolL^(-1).This dual-function detection of g-CNQDs has better practical application capability compared to other quantum dot detection.This study may provide a new strategy for g-CNQDs preparation and construct a fluorescence probe that can be used in various systems involving H_(2)O_(2)and Hg^(2+),providing better support for future bifunctional or multifunction studies.

关键词： carbon nitride quantum dots hydrogen peroxide Hg2+ fluorescence probe

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A“built-up”composite film with synergistic functionalities on Mg-2Zn-1Mn bioresorbable stents improves corrosion control effects and biocompatibility

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Bioactive Materials 2023年第7期25卷 223-238页

作者： Zhenglong Dou Shuiling chen Jiacheng Wang Li Xia Manfred F.Maitz Qiufen Tu wentai Zhang Zhilu Yang Nan Huang Key Lab of Advanced Technology of Materials of Education Ministry School of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu610031China Affiliated Dongguan Hospital Southern Medical UniversityDongguanGuangdong523059China Guangdong Provincial Key Laboratory of Cardiac Function and Microcirculation GuangzhouGuangdong510080China Department of Cardiology Third People’s Hospital of Chengdu Affiliated to Southwest Jiaotong UniversityChengdu610031China Max Bergmann Center of Biomaterials Dresden Leibniz Institute of Polymer Research DresdenHohe Strasse 601069DresdenGermany

Control of premature corrosion of magnesium(Mg)alloy bioresorbable stents(BRS)is frequently achieved by the addition of rare earth elements.However,limited long-term experience with these elements causes concerns for clinical application and alternative methods of corrosion control are sought after.Herein,we report a“built-up”composite film consisting of a bottom layer of MgF2 conversion coating,a sandwich layer of a poly(1,3-trimethylene carbonate)(PTMC)and 3-aminopropyl triethoxysilane(APTES)co-spray coating(PA)and on top a layer of poly(lactic-co-glycolic acid)(PLGA)ultrasonic spray coating to decorate the rare earth element-free Mg-2Zn-1Mn(ZM21)BRS for tailoring both corrosion resistance and biological functions.The developed“built-up”composite film shows synergistic functionalities,allowing the compression and expansion of the coated ZM21 BRS on an angioplasty balloon without cracking or peeling.Of special importance is that the synergistic corrosion control effects of the“built-up”composite film allow for maintaining the mechanical integrity of stents for up to 3 months,where complete biodegradation and no foreign matter residue were observed about half a year after implantation in rabbit iliac arteries.Moreover,the functionalized ZM21 BRS accomplished re-endothelialization within one month.

关键词： Magnesium alloys Bioresorbable stents Composite coating Corrosion control Biocompatibility

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混合动力专用变速器效率优化研究

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机电工程技术 2024年第1期53卷 167-170页

作者：吴为理张安伟周文太迟涵文陈雷广州汽车集团股份有限公司汽车工程研究院广州511434

混合动力技术目前汽车实现立竿见影节能减排效果的有效对策,而混合动力专用变速器是混合动力汽车(含插电式)的关键核心部件,直接影响整车能耗,因此效率优化和提升是混合动力专用变速器开发的重要课题。针对这一课题,基于混合动力专用变... 详细信息

混合动力技术目前汽车实现立竿见影节能减排效果的有效对策,而混合动力专用变速器是混合动力汽车(含插电式)的关键核心部件,直接影响整车能耗,因此效率优化和提升是混合动力专用变速器开发的重要课题。针对这一课题,基于混合动力专用变速器高度集成机械传动、电机、电机控制器和多驱动多模式的特性,从传动损耗、润滑油黏度、电机系统零扭补偿控制3个方面,通过理论分析和试验相结合进行研究。首先分析混合动力专用变速器传动损耗占比分布,进而得出效率优化的方向并试验验证优化效果;分析不同黏度油品对混合动力专用变速器系统效率的影响,并设定实际使用典型工况进行测试验证;对混合动力专用变速器直驱工况下电机控制进行分析和测试,揭示电机零扭状态下不同控制策略对系统效率的影响;为混合动力专用变速器实际开发过程的效率提升提供参考和依据。

关键词：混合动力专用变速器传动损耗油品黏度零扭补偿

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Temporal dynamics of SARS-CoV-2 genome mutations that occurred in vivo on an aircraft

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Biosafety and Health 2023年第1期5卷 62-67页

作者： Yaqing He Shengyuan Dang wentai Ma Long chen Renli Zhang Shujiang Mei Xinyi Wei Qiuying Lv Bo Peng Ying Sun Dongfeng Kong Jiancheng chen Shimin Li Xiujuan Tang Qingju Lu Can Zhu Zhigao chen Jia Wan Xuan Zou Mingkun Li Tiejiang Feng Lili Ren Jianwei Wang Shenzhen Research Center for Communicable Disease Control and Prevention Chinese Academy of Medical SciencesShenzhen 518055China Center for Disease Control and Prevention Shenzhen 518055China National Health Commission of the People’s Republic of China Key Laboratory of Systems Biology of Pathogens and Christophe Mérieux Laboratory Institute of Pathogen BiologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China University of Chinese Academy of Sciences Beijing 100190China Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciencesand China National Center for BioinformationBeijing 100101China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunming 650223China Key Laboratory of Respiratory Disease Pathogenomics Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

We analyzed variations in the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)genome during a flight-related cluster outbreak of coronavirus disease 2019(COVID-19)in Shenzhen,China,to explore the characteristics of SARS-CoV-2 transmission and intra-host single nucleotide variations(iSNVs)in a confined space.Thirty-three patients with COVID-19 were sampled,and 14 were resampled 3-31 days later.All 47 nasopharyngeal swabs were deep-sequenced.iSNVs and similarities in the consensus genome sequence were analyzed.Three SARS-CoV-2 variants of concern,Delta(n=31),Beta(n=1),and C.1.2(n=1),were detected among the 33 patients.The viral genome sequences from 30 Delta-positive patients had similar SNVs;14 of these patients provided two successive samples.Overall,the 47 sequenced genomes contained 164 iSNVs.Of the 14 paired(successive)samples,the second samples(T2)contained more iSNVs(median:3;95%confidence interval[95%CI]:2.77-10.22)than did the first samples(T1;median:2;95%CI:1.63-3.74;Wilcoxon test,P=0.021).38 iSNVs were detected in T1 samples,and only seven were also detectable in T2 samples.Notably,T2 samples from two of the 14 paired samples had additional mutations than the T1 samples.The iSNVs of the SARS-CoV-2 genome exhibited rapid dynamic changes during a flight-related cluster outbreak event.Intra-host diversity increased gradually with time,and new site mutations occurred in vivo without a population transmission bottleneck.Therefore,we could not determine the generational relationship from the mutation site changes alone.

关键词： SARS-CoV-2 Cluster epidemic Intra-host single nucleotide variation

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