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Long-term trends of fine particulate matter and chemical composition in the Pearl River Delta Economic Zone （PRDEZ）, China

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Frontiers of Environmental Science & Engineering 2016年第1期10卷 53-62页

作者： Xuemei WANG Weihua chen Duohong Chen Zhiyong WU Qi Fan School of Environmental Science and Engineering Sun Yat-Sen University Guangzhou 510275 China Guangdong Environmental Monitoring Center Guangzhou 510275 China

Understanding essential for formulating the trends in PM2.5 levels is clean air plans. This paper analyzes PM2.5 data from various published sources for the years 2000 to 2010 in the Pearl River Delta Economic Zone （PRDEZ）. The long-term variation in PM2.5 mass concentration is analyzed. Results show that PM2.5, organic carbon （OC）, elemental carbon （EC）, and SO24 show a similar trend, increasing before 2005 and then decreasing slightly. The annual average PM2.5 concentra- tion ranges from 49.1 μg·m-3 in 2000 to 64.3 μg·m-3 in 2010, with a peak of 84.1 μg· m3 in 2004. None of these 11 years meets the new National Ambient Air Quality standard （NAAQS） for PM2.5 （35 μg· m-3）. Overall average concentrations of OC, EC, and SO2/4 are 13.0, 6.5, and 11.8μg·m-3, respectively. NO3 and NH＋ respectively have concentrations of 1.5 μg·m-3 and 2.9 μg·m-3 in 2000 and 6.4 μg·m 3 and 5.3μg·m-3 in 2010, with a statistically significant average annual trend of＋ 0.2 μg·m-3 ·yr-1 and ＋ 0.1 μg· m-3. yr-1. In certain geographic regions, OC and EC contribute most of the PM2.5, while in other regions secondary water-soluble ions are more important. In general, OC and SO2/4- are the dominant components of PM2.5, contributing 20.6% and 18.6%, respectively. These results provide, for the first time, a better understanding of the long-term PM2.5 characteristics and trends, on a species-by-species basis, in the PRDEZ. The results indicate that PM2.5 abatement needs to prioritize secondary species.

关键词： long-term trends fine particulate matter,chemical components Pearl River Delta Economic Zone（PRDEZ）

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Space view of the decadal variation for typical air pollutants in the Pearl River Delta （PRD） region in China

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Frontiers of Environmental Science & Engineering 2016年第5期10卷 129-142页

作者： Zifeng WANG Min SHAO Liangfu chen Minghui TAO Liuju ZHONG Duohong Chen Meng FAN Yang WANG Xinhui WANG State Key Laboratory of Remote Sensing Science Jointly Sponsored by Institute of Remote Sensing and Digital Earth of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China College of Environmental Sciences and Engineering Peking University Beijing 100876 China Guangdong Environmental Monitoring Center Guangzhou 510308 China

The Pearl River Delta （PRD） is one of the most industrialized, urbanized and populated regions in China, and thus has been long suffering from severe air pollutions. Space data provide a unique perspective for investigating the atmospheric environment at a regional scale. By utilizing multiple satellite retrievals from 2005 to 2013, this study presented, for the first time, the spatial patterns and temporal trends of typical air pollutants over PRD and its vicinity. As viewed from space, aerosol optical depth （AOD）, NO2 and SO2 all had their higher values at the central part of PRD, and showed clear descending gradients as moving to the outskirt of this region. As to the inter-annual variation, all these pollutants had decreasing trends in PRD during the study period, which generally agreed with the relevant in situ measurements. However, the satellite retrievals differed from ground measurements when addressing NO2 and SO2 in the vicinity of PRD. This work also provides the inter-comparison among PRD and three other metropolitan clusters in China： PRD had relatively high AOD, moderate NO2 and low SO2 levels, and it was the only region achieving the effective reduction of NO2 and SO2 during last decade. Unlike the previous three pollutants, HCHO observed by satellite showed very special patterns： it had a relatively homogeneous spatial distribution over both of PRD and its vicinity, and presented an opposite increasing trend from 2005 to 2010. Moreover, PRD had the highest HCHO level among all the metropolitan clusters, hinting a considerable contribution of biogenic origins of HCHO in PRD.

关键词： The Pearl River Delta （PRD） Satellite monitoring Regional air quality Long-term trend HCHO

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A meteorologically adjusted ensemble Kalman filter approach for inversing daily emissions:A case study in the Pearl River Delta,China

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Journal of Environmental Sciences 2022年第4期34卷 233-248页

作者： Guanglin Jia Zhijiong Huang Xiao Tang Jiamin Ou Menghua Lu Yuanqian Xu Zhuangmin Zhong Qing’e Sha Huangjian Wu Chuanzeng Zheng Tao Deng Duohong Chen Min He Junyu Zheng School of Environment and Energy South China University of TechnologyUniversity Town CampusGuangzhou 510006China Institute for Environmental and Climate Research Jinan UniversityGuangzhou 511486China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Faculty of Social and Behavioural Sciences Utrecht UniversityUtrechtCH 3584the Netherlands Guangzhou Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510640China State Environmental Protection Key Laboratory of Regional Air Quality Monitoring Guangdong Environmental Monitoring CenterGuangzhou 510308China Department of Environmental Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China

The conventional Ensemble Kalman filter(EnKF),which is now widely used to calibrate emission inventories and to improve air quality simulations,is susceptible to simulation errors of meteorological inputs,making accurate updates of high temporal-resolution emission inventories challenging.In this study,we developed a novel meteorologically adjusted inversion method(MAEInv)based on the EnKF to improve daily emission estimations.The new method combines sensitivity analysis and bias correction to alleviate the inversion biases caused by errors of meteorological inputs.For demonstration,we used the MAEInv to inverse daily carbon monoxide(CO)emissions in the Pearl River Delta(PRD)region,China.In the case study,60%of the total CO simulation biases were associated with sensitive meteorological inputs,which would lead to the overestimation of daily variations of posterior emissions.Using the new inversion method,daily variations of emissions shrank dramatically,with the percentage change decreased by 30%.Also,the total amount of posterior CO emissions estimated by the MAEInv decreased by 14%,indicating that posterior CO emissions might be overestimated using the conventional EnKF.Model evaluations using independent observations revealed that daily CO emissions estimated by MAEInv better reproduce the magnitude and temporal patterns of ambient CO concentration,with a higher correlation coefficient(R,+37.0%)and lower normalized mean bias(NMB,-17.9%).Since errors of meteorological inputs are major sources of simulation biases for both low-reactive and reactive pollutants,the MAEInv is also applicable to improve the daily emission inversions of reactive pollutants.

关键词： Emission inversion Daily emissions Meteorological adjustment Ensemble Kalman filter

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Fast increasing of surface ozone concentrations in Pearl River Delta characterized by a regional air quality monitoring network during 2006–2011

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Journal of Environmental Sciences 2014年第1期26卷 23-36页

作者： Jinfeng Li Keding Lu Wei Lv Jun Li Liuju Zhong Yubo Ou Duohong Chen Xin Huang Yuanhang Zhang College of Environmental Sciences Engineering Peking University Guangdong Provincial Environmental Monitoring Center

Based on the observation by a Regional Air Quality Monitoring Network including 16 monitoring stations, temporal and spatial variations of ozone （O3）, NO2 and total oxidant （Ox） were analyzed by both linear regression and cluster analysis. A fast increase of regional O3 concentrations of 0.86 ppbWyr was found for the annual averaged values from 2006 to 2011 in Guangdong, China. Such fast O3 increase is accompanied by a correspondingly fast NOx reduction as indicated by a fast NO2 reduction rate of 0,61 ppbV/yr. Based on a cluster analysis, the monitoring stations were classified into two major categories - rural stations （non-urban） and suburban/urban stations. The 03 concentrations at rural stations were relatively conserved while those at suburban/urban stations showed a fast increase rate of 2.0 ppbV/yr accompanied by a NO2 reduction rate of 1.2 ppbV/yr. Moreover, a rapid increase of the averaged O3 concentrations in springtime （13%/yr referred to 2006 level） was observed, which may result from the increase of solar duration, reduction of precipitation in Guangdong and transport from Eastern Central China. Application of smog production algorithm showed that the photochemical O3 production is mainly volatile organic compounds （VOC）-controlled. However, the photochemical O3 production is sensitive to both NOx and VOC for O3 pollution episode. Accordingly, it is expected that a combined NOx and VOC reduction will be helpful for the reduction of the O3 pollution episodes in Pearl River Delta while stringent VOC emission control is in general required for the regional O3 pollution control.

关键词： O3 cluster analysis temporal variation smog production algorithm Pearl River Delta

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基于AHP-熵权-可拓云模型的城市轨道交通跨线运营效果评价

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铁道运输与经济 2023年第2期45卷 118-125页

作者：陈虹兵王多宏广州地铁设计研究院股份有限公司交通规划分院广东广州510000 西南交通大学交通运输与物流学院四川成都610031

为客观全面评价城市轨道交通跨线运营效果,从客流匹配度、服务水平、运力衔接、运营管理4个层面构建了城市轨道交通跨线运营效果评价指标体系;提出了基于AHP-熵权-可拓云模型的城市轨道交通跨线运营效果评价模型,该模型采用AHP-熵权法... 详细信息

为客观全面评价城市轨道交通跨线运营效果,从客流匹配度、服务水平、运力衔接、运营管理4个层面构建了城市轨道交通跨线运营效果评价指标体系;提出了基于AHP-熵权-可拓云模型的城市轨道交通跨线运营效果评价模型,该模型采用AHP-熵权法对评价指标进行组合赋权,可避免单一赋权方法带来的不足,同时将正态云模型引入可拓理论进行评价,能有效刻画评价过程中评价指标等级的模糊性;最后,以广州地铁3号线与3北线、14号线与知识城线2条运营线路实测数据对所提模型进行验证。结果表明:3号线与3北线跨线运营效果中等,14号线与知识城线跨线运营效果良好,并且14号线与知识城线的跨线工程整体效果及水平比3号线与3北线跨线工程高,说明所提方法具有较好的可行性和适用性。

关键词：城市轨道交通跨线运营 AHP 熵权法可拓云理论

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负载褐藻多酚的丝素蛋白GBR生物膜制备及其性能的体外实验研究

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安徽医科大学学报 2023年第6期58卷 885-890页

作者：陈文泽邹多宏安徽医科大学口腔医学院安徽医科大学附属口腔医院安徽省口腔疾病研究重点实验室合肥230032 上海交通大学口腔医学院上海交通大学医学院附属第九人民医院口腔外科上海市口腔医学重点实验室上海200001

目的通过制备负载褐藻多酚(PT)的双层丝素蛋白(SF)膜,测试其力学性能、生物相容性及其对成骨分化的影响,研究其作为引导骨再生屏障膜的可能性。方法将不同脱胶时间处理后的SF溶液通过溶液浇筑技术、定向冷冻技术以及冷冻干燥技术处理后... 详细信息

目的通过制备负载褐藻多酚(PT)的双层丝素蛋白(SF)膜,测试其力学性能、生物相容性及其对成骨分化的影响,研究其作为引导骨再生屏障膜的可能性。方法将不同脱胶时间处理后的SF溶液通过溶液浇筑技术、定向冷冻技术以及冷冻干燥技术处理后制备成SF双层膜,采用力学万能试验机测定湿态条件下各组膜样品(n=5)的抗拉强度。取抗拉强度最大的SF双层膜所对应的SF溶液重新制备膜样品,用扫描电镜观察其微观结构。通过在粗糙面负载PT制备PT-SF双层膜,使用傅里叶红外光谱仪分析PT与SF双层膜的相互作用。利用扫描电镜观察人牙槽骨来源的骨髓间充质干细胞(hABMSCs)在粗糙面的黏附情况,通过CCK-8及活死细胞染色探究PT-SF双层膜的生物相容性。用qRT-PCR法、ALP染色和茜素红染色检测各组hABMSCs的成骨向分化情况。结果由脱胶时间为30 min的SF溶液制备出的SF双层膜的抗拉强度最大,达(3.293±0.1228)MPa。SF双层膜的光滑面致密光滑,粗糙面呈纵向有序的疏松多孔结构。褐藻多酚通过氢键、疏水作用力等方式负载到SF双层膜的粗糙面上,空白组、SF组及PT-SF组之间的CCK-8及活死细胞染色结果均无明显差异,且与空白组和SF组相比PT-SF促进了hABMSCs的成骨向分化。结论PT-SF双层膜兼具良好的机械性能和生物学性能,可在一定程度上促进hABMSCs的成骨向分化。该研究成功制备了PT-SF双层膜。

关键词：褐藻多酚丝素蛋白复合膜定向冷冻成骨分化

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典型大气细颗粒物与臭氧复合污染过程中挥发性有机物的贡献及来源

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环境污染与防治 2022年第9期44卷 1222-1227页

作者：陈耿李瑞瑜陈春贻陈多宏广东省生态环境监测中心广东广州510308

针对2020年4月25-30日在广东鹤山发生的细颗粒物(PM_(2.5))与臭氧(O_(3))复合污染过程,分析了挥发性有机物(VOCs)的O_(3)生成潜势(OFP)和二次有机气溶胶(SOA)生成潜势,并对VOCs来源进行了解析。结果表明,PM_(2.5)和O_(3)小时质量浓度分... 详细信息

针对2020年4月25-30日在广东鹤山发生的细颗粒物(PM_(2.5))与臭氧(O_(3))复合污染过程,分析了挥发性有机物(VOCs)的O_(3)生成潜势(OFP)和二次有机气溶胶(SOA)生成潜势,并对VOCs来源进行了解析。结果表明,PM_(2.5)和O_(3)小时质量浓度分别为20~102、6~292μg/m^(3),O_(3)和PM_(2.5)污染交替发生。VOCs小时体积分数为4.64×10^(-9)~6.13×10^(-8),污染前期(25-26日)主要属于氮氧化物(NO_(x))控制;污染中期(27-28日)同时受到VOCs和NO_(x)控制;污染后期(29-30日)属于VOCs控制。OFP贡献最大的前10种VOCs物种包括芳香烃和链烃,而SOA生成潜势贡献最大的前10种VOCs物种均为芳香烃。VOCs主要来源依次为交通源、溶剂挥发源、大气中本身的老化VOCs、石化工业源和燃料使用源。

关键词：复合污染挥发性有机物来源解析生成潜势

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区域轨道交通互联互通协同发展理论

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综合运输 2021年第12期43卷 3-8页

作者：陈虹兵王多宏广州地铁设计研究院股份有限公司广东广州510000 西南交通大学交通运输与物流学院四川成都610031

本文结合轨道交通特征和协同运输目标,针对区域轨道交通互联互通协同运输问题,提出区域轨道交通互联互通协同运输理论。首先明确区域轨道交通互联互通协同运输内涵条件与维度界定方法;其次提出区域轨道交通互联互通协同运输理论框架,在... 详细信息

本文结合轨道交通特征和协同运输目标,针对区域轨道交通互联互通协同运输问题,提出区域轨道交通互联互通协同运输理论。首先明确区域轨道交通互联互通协同运输内涵条件与维度界定方法;其次提出区域轨道交通互联互通协同运输理论框架,在分析区域轨道交通互联互通协同过程的基础上,建立区域轨道交通互联互通协同机制模型,从系统运行和进化的角度分析协同形成的动因、实现协同目标的条件、协同实现过程的约束控制以及信息反馈过程,从理论上支撑区域轨道交通协同发展。

关键词：区域轨道交通协同运输协同机制模型互联互通协同运输维度

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The role of DNA methylation in the maintenance of phenotypic variation induced by grafting chimerism in Brassica

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Horticulture Research 2023年第3期10卷 164-175页

作者： Ke Liu Tingjin Wang duohong Xiao Bin Liu Yang Yang Kexin Xu Zhenyu Qi Yan Wang Junxing Li Xun Xiang Lu Yuan Liping chen Department of Horticulture College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310058China Agricultural Experiment Station Zhejiang UniversityHangzhou 310058China

Grafting facilitates the interaction between heterologous cells with different genomes,resulting in abundant phenotypic variation,which provides opportunities for crop improvement.However,how grafting-induced variation occurs and is transmitted to progeny remains elusive.A graft chimera,especially a periclinal chimera,which has genetically distinct cell layers throughout the plant,is an excellent model to probe the molecular mechanisms of grafting-induced variation maintenance.Here we regenerated a plant from the T-cell layer of a periclinal chimera,TCC(where the apical meristem was artificially divided into three cell layers–from outside to inside,L1,L2,and L3;T=Tuber mustard,C=red Cabbage),named rTTT0(r=regenerated).Compared with the control(rsTTT,s=self-grafted),rTTT0 had multiple phenotypic variations,especially leaf shape variation,which could be maintained in sexual progeny.Transcriptomes were analyzed and 58 phenotypic variation-associated genes were identified.Whole-genome bisulfite sequencing analyses revealed that the methylome of rTTT0 was changed,and the CG methylation level was significantly increased by 8.74%.In rTTT0,the coding gene bodies are hypermethylated in the CG context,while their promoter regions are hypomethylated in the non-CG context.DNA methylation changes in the leaf shape variation-associated coding genes,ARF10,IAA20,ROF1,and TPR2,were maintained for five generations of rTTT0.Interestingly,grafting chimerism also affected transcription of the microRNA gene(MIR),among which the DNA methylation levels of the promoters of three MIRs associated with leaf shape variation were changed in rTTT0,and the DNA methylation modification of MIR319 was maintained to the fifth generation of selfed progeny of rTTT0(rTTT5).These findings demonstrate that DNA methylation of coding and non-coding genes plays an important role in heterologous cell interaction-induced variation formation and its transgenerational inheritance.

关键词： phenotypic maintained grafting

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珠三角典型地区大气污染时段VOCs特征及化学反应活性

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环境科学学报 2023年第1期43卷 229-236页

作者：廖彤张涛周炎陈多宏王新明广东省生态环境监测中心国家环境保护区域空气质量监测重点实验室广东省环境保护大气二次污染研究重点实验室广州510308 广东省环珠江口气候环境与空气质量变化野外科学观测研究站广州510275 中国科学院广州地球化学研究所有机地球化学国家重点实验室广州510640

于2016年在广东大气超级监测站,开展4个季节的VOCs、O_(3)和PM_(2.5)长时间、高分辨率的连续观测,共获得2142组有效数据,并利用OH消耗速率(L_(OH))、臭氧生成潜势(OFP)和二次有机气溶胶生成潜势(SOAFP)3种评价方法以及HYSPLIT模型,分析... 详细信息

于2016年在广东大气超级监测站,开展4个季节的VOCs、O_(3)和PM_(2.5)长时间、高分辨率的连续观测,共获得2142组有效数据,并利用OH消耗速率(L_(OH))、臭氧生成潜势(OFP)和二次有机气溶胶生成潜势(SOAFP)3种评价方法以及HYSPLIT模型,分析珠三角典型地区大气污染时段VOCs特征及化学反应活性.结果表明,PM_(2.5)高值时段,除异戊二烯外,其余各种VOCs的平均浓度水平高于O_(3)高值时段.3种情境中,VOCs化学反应活性由强到弱依次为PM_(2.5)高值时段、观测期间、O_(3)高值时段.在O_(3)高值时段,来自珠三角东部地区气团中VOCs的浓度水平最高,而来自珠江西岸气团中VOCs的L_(OH)和OFP最高,其次为来自珠三角东部的气团,这说明在珠江西岸和珠三角东部地区有大量的强化学反应活性污染物排放.来自北方内陆地区气团中苯系物占比较高,其SOAFP最高.在PM_(2.5)高值时段,来自南部海洋气团中VOCs的混合比、L_(OH)、OFP和SOAFP均最高,其次为来自东北内陆地区气团中VOCs的OFP和SOAFP.来自粤西南地区的气团,由于苯系物和低碳烯烃占比达到50%,其L_(OH)仅次于来自于南部海洋的气团.

关键词：珠三角挥发性有机物二次有机气溶胶化学反应活性轨迹聚类

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