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Investigating missing sources of glyoxal over China using a regional air quality model (RAMS-CMAQ)

Journal of Environmental Sciences 2018年第9期30卷 108-118页

作者： Jialin Li Meigen Zhang guiqian Tang Fangkun Wu Leonardo M.A. Alvarado Mihalis Vrekoussis Andreas Richter John P. Burrows State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPQ) Institute of Atmospheric Physics (IAP)Chinese Academy of Sciences (CAS) Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Center for Excellence in Urban Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China Institute of Environmental Physics and Remote Sensing IUP University of Bremen D-28203 Bremen Germany Center of Marine Environmental Sciences MARUM University of Bremen D-28203 Bremen Germany Energy Environment and Water Research Center the Cyprus Institute CY2121 Nicosia Cyprus

Currently, modeling studies tend to significantly underestimate observed space-based glyoxal （CHOCHO） vertical column densities （VCDs）, implying the existence of missing sources of giyoxal. Several recent studies suggest that the emissions of aromatic compounds and molar yields of glyoxal in the chemical mechanisms may both be underestimated, which can affect the simulated glyoxal concentrations. In this study, the influences of these two factors on glyoxal amounts over China were investigated using the RAMS-CMAQ modeling system for January and July 2014. Four sensitivity simulations were performed, and the results were compared to satellite observations. These results demonstrated significant impacts on glyoxal concentrations from these two factors. In case 1, where the emissions of aromatic compounds were increased three-fold, improvements to glyoxal VCDs were seen in high anthropogenic emissions regions. In case 2, where molar yields of glyoxal from isoprene were increased five-fold, the resulted concentrations in July were B-B-fold higher, achieving closer agreement between the modeled and measured glyoxal VCDs. The combined changes from both cases 1 and 2 were applied in case B, and the model succeeded in further reducing the underestimations of glyoxal VCDs. However, the results over most of the regions with pronounced anthropogenic emissions were still underestimated. So the molar yields of giyoxal from anthropogenic precursors were considered in case 4. With these additional mole yield changes （a two-fold increase）, the improved concentrations agreed better with the measurements in regions of the lower reaches of the Yangtze River and Yellow River in January but not in July.

关键词： Glyoxal Volatile organic compounds Molar yields RAMS-CMAQ China

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Influence of circulation types on temporal and spatial variations of ozone in Beijing

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Journal of Environmental Sciences 2023年第8期130卷 37-51页

作者： Xiaowan Zhu JinWu guiqian Tang Lin Qiao Tingting Han Xiaomei Yin Xiangxue Liu Ziming Li Yajun Xiong Di He Zhiqiang Ma China Meteorological Administration Institute of Urban MeteorologyBeijing 100089China Beijing Shangdianzi Regional Atmosphere Watch Station Beijing 100089China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Chinese Academy of SciencesInstitute of Atmospheric PhysicsBeijing 100029China

This study analyzes the impact of circulation types(CTs)on ozone(O_(3))pollution in *** easterly high-pressure(SWW)circulation occurred most frequently(30%;276 day),followed by northwesterly high-pressure(AN)circulation(24.3%;224 day).The SWW type had the highest O_(3) anomaly of+17.28μg/m^(3),which was caused by excellent photochemical reactions,poor diffusion ability and regional *** to the higher humidity and precipitation in the low-pressure type(C),the O_(3) increase(+8.02μg/m^(3))was less than that in the SWW *** diffusion/wet deposition and weak formation ability contributed to O_(3) decrease in AN(-12.54μg/m^(3))and northerly high-pressure(ESN)CTs(-12.26μg/m^(3)).The intra-area transport of O_(3) was significant in polluted circulations(SWW-and C-CTs).In addition,higher temperature,radiation and less rainfall also contributed to higher O_(3) in northern Beijing under the SWW *** the clean CTs(AN and ESN CTs),precursor amount and intra-area transport played a dominant role in O_(3) *** the northeasterly low-pressure CT,better formation conditions and higher precursor amount combined with the intra-area southerly transport to cause higher O_(3) values in the south than in the *** higher O_(3) in the northwestern area under the northeasterly high-pressure type was influenced by weaker titration loss and high O_(3) concentration in previous *** variation in the CTs contributed up to 86.1%of the annual variation in O_(3).About 78%-83%of the diurnal variation in O_(3) resulted from local meteorological factors.

关键词： Ozone Objective synoptic classification Temporal variation and spatial distribution Intra-area transport

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Atmospheric oxidizing capacity in autumn Beijing:Analysis of the O_(3) and PM_(2.5) episodes based on observation-based model

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Journal of Environmental Sciences 2023年第2期124卷 557-569页

作者： Chenhui Jia Shengrui Tong Xinran Zhang Fangjie Li Wenqian Zhang Weiran Li Zhenwang Gen Zhang guiqian Tang Zirui Liu Maofa Ge State Key Laboratory for Structural Chemistry of Unstable and Stable Species CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of Chemistry Liaoning UniversityShenyang 110036China State Key Laboratory of Severe Weather&Key Laboratory for Atmospheric Chemistry of CMA Institute of Atmospheric CompositionChinese Academy of Meteorological SciencesBeijing 100081China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Atmospheric oxidizing capacity(AOC)is the fundamental driving factors of chemistry process(e.g.,the formation of ozone(O_(3))and secondary organic aerosols(SOA))in the ***,accurate quantification of AOC still remains *** this study,a comprehensive field campaign was conducted during autumn 2019 in downtown of Beijing,where O_(3) and PM_(2.5) episodes had been experienced *** observation-based model(OBM)is used to quantify the AOC at O_(3) and PM_(2.5) *** strong intensity of AOC is found at O_(3) and PM2.5 episodes,and hydroxyl radical(OH)is the dominating daytime oxidant for both *** photolysis of O_(3) is main source of OH at O_(3) episode;the photolysis of nitrous acid(HONO)and formaldehyde(HCHO)plays important role in OH formation at PM_(2.5) *** radicals loss routines vary according to precursor pollutants,resulting in different types of air pollution.O_(3) budgets and sensitivity analysis indicates that O_(3) production is transition regime(both VOC and NOx-limited)at O3 *** heterogeneous reaction of hydroperoxy radicals(HO_(2))on aerosol surfaces has significant influence on OH and O_(3) production *** HO_(2) uptake coefficient(γHO_(2))is the determining factor and required accurate measurement in real atmospheric *** findings could provide the important bases for coordinated control of PM_(2.5) and O_(3) pollution.

关键词： Pollution episode Observation-based model Atmospheric oxidizing capacity Heterogeneous reaction Hydroxyl radical Budgets

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Reductions of PM_(2.5) in Beijing-Tianjin-Hebei Urban Agglomerations during the 2008 Olympic Games

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Advances in Atmospheric Sciences 2012年第6期29卷 1330-1342页

作者：辛金元王跃思王莉莉唐贵谦孙扬潘月鹏吉东生 The State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences

The Atmospheric Environmental Monitoring Network successfully undertook the task of monitoring the atmospheric quality of Beijing and its surrounding area during the 2008 Olympics. The results of this monitoring show that high concentrations of PM2.5 pollution exhibited a regional pattern during the monitoring period （1 June-30 October 2008）. The PM2.5 mass concentrations were 53 μg m-3, 66 p.g m-3, and 82 μg m-3 at the background site, in Beijing, and in the Beijing-Tianjin-Hebei urban agglomerations, respectively. The PM2.5 levels were lowest during the 2008 Olympic Games （8-24 August）： 35μg m-3 at the background site, 42 μg m-3 in Beijing and 57 μg m-3 in the region. These levels represent decreases of 49%, 48% and 56%, respectively, compared to the prophase mean concentration before the Olympic Games. Emission control measures contributed 62% 82% of the declines observed in Beijing, and meteorological conditions represented 18%-38%. The concentration of fine particles met the goals set for a ＂Green Olympics.＂

关键词： PM2.5 the 2008 Olympic Games the urban agglomerations the network

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Observation and modeling of vertical carbon dioxide distribution in a heavily polluted suburban environment

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Atmospheric and Oceanic Science Letters 2020年第4期13卷 371-379页

作者： BAO Zhongxiu HAN Pengfei ZENG Ning LIU Di CAI Qixiang wang Yinghong TANG guiqian ZHENG Ke YAO Bo College of Atmospheric Sciences Chengdu University of Information TechnologyChengduChina State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Department of Atmospheric and Oceanic Science and Earth System Science Interdisciplinary CenterUniversity of MarylandCollege ParkMarylandUSA State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina School of Atmospheric Physics Nanjing University of Information Science and TechnologyNanjingChina Meteorological Observation Centre of China Meteorological Administration BeijingChina

The vertical distribution of carbon dioxide(CO2)is important for the calibration and validation of transport models and remote sensing *** to the large mass and volume of traditional instruments as well as supporting systems,in-situ measurements of the CO2 vertical profile within the boundary layer are *** study used a miniaturized CO2 monitoring instrument based on a low-cost non-dispersive infrared(NDIR)sensor to measure the CO2 vertical profile and meteorological parameters of the lower troposphere(0–1000 m)in southwestern Shijiazhuang,Hebei Province,*** sensors were onboard a tethered balloon with two processes:the ascending process and the descending *** results showed that the overall trend of CO2 concentration decreased with *** conditions and CO2 emission sources caused fluctuations in CO2 *** CO2 concentration varied from morning to afternoon due mainly to the faster spread of air mass during daytime,with strong convections and the accumulation of emissions at *** low-cost sensor produced results consistent with the traditional gas chromatography *** Weather Research and Forecasting model could not capture the CO2 profiles well due mainly to the bad performances in boundary layer height and the potential outdated fossil fuel emissions around the experimental *** experiment is the first successful attempt to observe the CO2 vertical distribution in the lower troposphere by using lowcost NDIR *** results help us to understand the vertical structure of CO2 in the boundary layer,and provide data for calibrating and validating transport models.

关键词： Low cost sensor co2 vertical profile tethered balloon meteorological conditions non-dispersive infrared(NDIR)

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Secondary organic aerosols in a typical urban site in North China: significant anthropogenic contributions to heavy pollution

Secondary organic aerosols in a typical urban site in North ...

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第十三届全国气溶胶会议

作者： LIU Yusi LI Xingru TANG guiqian wang Lili LV Bo GUO Xueqing wang Yuesi Department of Chemistry Analytical and Testing CenterCapital Normal University State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences Jinan Environmental Monitoring Center Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of Sciences

Secondary organic aerosols(SOAs) affect the chemical constitution of the atmosphere, earth’s radiative balance and water *** comprise biogenic SOAs(BSOAs) and anthropogenic SOAs(ASOAs), but whether BSOAs or ASOAs are the dominant contributors to haze pollution remains poorly *** this study, particulate samples were collected from September 2014 to August 2015 at an urban site in Jinan, which is the capital of Shandong Province and a typical city in the North China Plain(NCP).The PM samples were analyzed for BSOA(isoprene(SOA I) and monoterpenes(SOA)) and ASOA(aromatic(SOA)) *** concentrations of the SOA tracer(1.1 ± 1.0 ng m) were lowest, and those of SOA I tracers(41.8 ± 86.2 ng m) were highest, with the concentrations of SOA tracers(19.4 ± 9.9 ng m) being *** BSOA tracers were more abundant in the summer and less abundant in the *** SOA I and SOA increased with increasing ozone level but decreased with increasing NOx *** analysis revealed a good correlation between 2,3-dihydroxy-4-oxopentanoic acid(DHOPA) and levoglucosan levels in three *** results suggested that biomass burning(BB) activities occurring in the NCP can enhance the emissions of aromatics and should be controlled, especially in the autumn and *** aerosols exhibited higher SOA tracer levels on hazy *** secondary organic carbon(SOC) was the main contributor to organic carbon(OC).As PM levels increased, the contributions of SOA *** results indicate that reducing anthropogenic emissions is necessary to prevent SOA pollution, especially during heavy pollution episodes.

关键词： seasonal variations biogenic secondary organic aerosols biomass burning anthropogenic contributions

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电弧增材制造复杂截面等距填充路径生成算法

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华中科技大学学报（自然科学版） 2022年第12期50卷 70-74页

作者：张建生王航周杰肖贵乾重庆大学材料科学与工程学院重庆400044 重庆杰品科技股份有限公司重庆400050

为了解决增材制造、计算机数控(CNC)加工中的任意复杂截面的等距填充问题,提出了一种基于水平集函数的等距填充路径生成算法.首先,针对复杂截面等距填充问题的特点,提出了水平集函数演变偏微分方程及其演变规则,通过有限差分法构建了前... 详细信息

为了解决增材制造、计算机数控(CNC)加工中的任意复杂截面的等距填充问题,提出了一种基于水平集函数的等距填充路径生成算法.首先,针对复杂截面等距填充问题的特点,提出了水平集函数演变偏微分方程及其演变规则,通过有限差分法构建了前向欧拉迭代公式并设计了整个等距填充的算法流程;然后,使用一个复杂截面进行了有限差分数值实验验证,结果表明提出的新算法能够避免复杂的多边形交、差、并、裂解等运算,高效处理复杂截面的等距随形状填充;最后,以一个失效的曲轴热锻模为例,进行了分层切片、等距填充规划处理和电弧熔丝增材制造修复实验,验证了算法的有效性.

关键词：电弧熔丝增材制造复杂截面等距填充热锻模水平集有限差分

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硼酸类化学传感器的研究进展

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有机化学 2018年第5期38卷 1035-1051页

作者：王浩王凯孙捷方桂迁姚庆强吴忠玉济南大学山东省医学科学院医学与生命科学学院济南250200 山东省医学科学院药物研究所济南250062 国家卫生部生物技术药物重点实验室济南250062 山东省罕少见病重点实验室济南250062

检测和识别体内某些物质,例如唾液酸化LewisA/X,能够为疾病的诊断、治疗、预后、分子示踪及深入研究相关疾病机理等方面提供重要参考.因此,开发高选择性、高灵敏度的化学传感器具有重要价值.苯基硼酸化合物由于其特殊结构,能够与糖、儿... 详细信息

检测和识别体内某些物质,例如唾液酸化LewisA/X,能够为疾病的诊断、治疗、预后、分子示踪及深入研究相关疾病机理等方面提供重要参考.因此,开发高选择性、高灵敏度的化学传感器具有重要价值.苯基硼酸化合物由于其特殊结构,能够与糖、儿茶酚胺以及氟化物、氰化物等路易斯碱相互作用,使得其能够作为传感器用于相关物质的荧光识别和检测;且此类化合物具有高选择性、高效能、分析速度快等优点.近几年,将硼酸与纳米粒子、量子点等新材料相结合,设计出性能更加优越的硼酸传感器.综述了硼酸类化合物在传感器方面的研究进展.

关键词：硼酸化学传感器荧光糖电化学

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圆形钢筋混凝土桥墩等效塑性铰长度

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土木工程学报 2016年第2期49卷 87-97页

作者：李贵乾唐光武郑罡广西壮族自治区交通规划勘察设计研究院广西南宁530029 招商局重庆交通科研设计院有限公司桥梁结构动力学国家重点实验室重庆400067 重庆交通大学重庆400074

基于桥墩极限位移三分量模型,从弯曲、剪切和纵筋滑移变形等三方面分析了桥墩塑性铰长度的主要影响参数;通过40个圆形钢筋混凝土桥墩试验数据的分析,建议了桥墩塑性铰长度的理论公式及经验公式;并对建议及各规范的塑性铰长度公式进行了... 详细信息

基于桥墩极限位移三分量模型,从弯曲、剪切和纵筋滑移变形等三方面分析了桥墩塑性铰长度的主要影响参数;通过40个圆形钢筋混凝土桥墩试验数据的分析,建议了桥墩塑性铰长度的理论公式及经验公式;并对建议及各规范的塑性铰长度公式进行了模型桥墩、足尺桥墩和实桥桥墩的验证。结果表明:钢筋混凝土桥墩塑性铰长度主要随墩高、截面高度、材料特性参数(fydb/fc')及纵筋率的增大而增大,与轴压比、配箍率等关系不大;与试验结果相比,就平均意义而言,各国规范塑性铰长度计算结果偏于安全,但均有较大的离散性,日本JRA规范最为保守,中国《公路桥梁抗震设计细则》(JTG/T B02-01—2008)较美国Caltrans规范及欧洲Eurocode8规范保守;建议的塑性铰长度理论公式与日本JRA规范相当,建议的塑性铰长度经验公式在平均意义上与美国Caltrans规范及欧洲Eurocode8规范一致,但具有较小的变异系数和较高的保证率,优于其他公式。

关键词：钢筋混凝土桥墩塑性铰长度塑性曲率弯曲变形剪切变形纵筋滑移变形

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十三陵蓄能电厂3号发电机定子绕组防晕检修处理

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水力发电 2006年第7期32卷 83-84页

作者：赵贵前北京十三陵蓄能电厂北京102200

发电机定子绕组防晕不仅是对发电机制造工艺的一项重要要求,也是运行检修重点监测的项目。在绕组端部区域,由于电场强度相对较大且极不均匀,最容易发生电晕。对十三陵蓄能电厂3号机组定子绕组防晕层的故障作了分析,并采取了检修处理,其... 详细信息

发电机定子绕组防晕不仅是对发电机制造工艺的一项重要要求,也是运行检修重点监测的项目。在绕组端部区域,由于电场强度相对较大且极不均匀,最容易发生电晕。对十三陵蓄能电厂3号机组定子绕组防晕层的故障作了分析,并采取了检修处理,其方法为电力行业类似问题的解决提供了一定的参考。

关键词：维修电晕线棒防晕层发电机定子绕组十三陵蓄能电厂

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