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Particle size distribution and characteristics of polycyclic aromatic hydrocarbons during a heavy haze episode in Nanjing,China

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Particuology 2015年第1期13卷 127-134页

作者： Qingzi Meng shuxian fan Jiabao He Jian Zhang Yu Sun Yue Zhang fan Zu Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science and Technology Department of Atmospheric Physics Nanjing University of Information Science and Technology Jiangsu Institute of Meteorological Sciences

A heavy haze episode caused by agricultural burning occurred in Nanjing from November 7 to November 8, 2009. PM10 samples were collected on normal and hazy days from November I to November 14, 2009 at both city and suburban sites of Nanjing. Sixteen PAHs were measured during the day and at night. The results show that the concentrations of the particles were as high as 579.55 and 573.43 μg/m^3 during the haze episode at the city and suburban sites, respectively, 3-4 times higher than those on a normal day. The proportions of fine particles during the haze episode were also higher than those on a normal day. The changes in the concentrations of PAHs were in accordance with the concentrations of the particles. High- molecular-weight PAHs composed approximately 80% of the total PAHs on normal days and during the haze episode. The concentration of PAHs in fine fractions significantly increased during the haze episode, and this increase was most obvious at night at the city site, The proportion of total carcinogenic PAHs in fine particles was relatively high during the haze episode at both sampling sites, particularly at night at the city site.

关键词： Polycyclic aromatic hydrocarbons Agricultural burning Haze episode Particle size distribution Meteorological conditions Nanjing

Particle size distribution and characteristics of Polycyclic Aromatic Hydrocarbons during an autumn haze episode in Nanjing,China

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Particle size distribution and characteristics of Polycyclic...

Characteristics,distribution and source apportionment of polycyclic aromatic hydrocarbons in fine particulate in Nanjing,China

十一届全国气溶胶会议暨第十届海峡两岸气溶胶技术研讨会

作者： Qingzi Meng shuxian fan fan Zu Jiabao He Jian Zhang Yu Sun Department of Atmospheric Physics Nanjing University of Information Science and Technology Key Laboratory for Meteorological Disaster Ministry of EducationNanjing University of Information Science and Technology

The purpose of this study is to understand the characteristics of pollution and distribution of polycyclic aromatic hydrocarbons（PAHs） in fine（PM2.1） and coarse（PM2.1-10） particles at suburban and city site during an autumn haze episode in Nanjing. PM10 samples were collected from Nov. 1, 2009 to Nov. 14, 2009. Filter samples were extracted by using Soxhlet and analyzed by using a gaseous chromatograph/mass spectrometer（GC-MS）. Sixteen PAHs were measured at day and night of suburban and city site in this study. The results show that the concentrations of particles could be as high as 579.55 and 573.43μg/m-3 at suburban and city site during the haze episode, it was 3-4 times higher than normal days and the proportion of fine particles in the haze episode was also higher than normal days;the varies of concentration of PAHs were in accord with the concentration of particles. The concentrations of particles and PAHs at night were higher than in the daytime both at city and suburban site during the haze episode;the main kinds of PAHs in particles were the high-molecular-weight PAHs which make up approximately 80% of the total PAHs no matter in normal days or haze episode. It also turns out that wet removal mechanism has strong scavenging ability for pollutants, especially for the fine fraction;the spectral distribution of PAHs was the transfer of coarse fraction to fine fraction and this phenomenon was most obvious at night at city site, which indicates that the emission sources and the condition of boundary layer play important roles in the distribution and concentration of PAHs;the concentration of CAN-PAHs is relatively higher at both sampling sites and periods, the highest proportion of CAN-PAHs appear at the night of city site, it was as high as 52% of total PAHs, it is higher risk exposures for the people in Nanjing.

关键词： Polycyclic aromatic hydrocarbons Haze episode Particle size distribution Meteorological conditions Nanjing

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Characteristics,distribution and source apportionment of pol...

MMC与混合式直流断路器开关操作的瞬态电场实测及其在状态监测中的应用

十一届全国气溶胶会议暨第十届海峡两岸气溶胶技术研讨会

作者： Jiabao He shuxian fan fan Zu Qingzi Meng Jian Zhang Yu Sun Department of Atmospheric Physics Nanjing University of Information Science and Technology Key Laboratory for Meteorological Disaster Ministry of EducationNanjing University of Information Science and Technology

A study of 16 EPA priority polycyclic aromatic hydrocarbons（PAHs） associated with particulate matter（PM2.1） in the ambient air in Nanjing was carried out from November 2009 to July *** PAH concentrations during the sampling period were in the range of 25.91-102.25 ng/m3（average value: 58.09ng/m3）, with relatively higher values in nighttime rather than daytime. Differing from other studies, PM2.1-bound PAHs were found to be more abundant at suburban site, which was due to the sharp increase in vehicle numbers for recent years in suburban along with the development of urbanization and the unique industrial circumstance around the suburban site. What’s more, similarities between the profiles for two sites were identified by using coefficient of divergence, predicting PAHs from the two districts have common sources. Correlation analysis proved the PM2.1-bound PAHs mainly derived from combustion activities and the species of Bb F, Chr, Fla, In P, Be P, Bghi P, all of which were vehicle markers, dominated the PAH profiles. The average concentrations in four reasons were in the order of winter＞spring＞autumn＞summer, owing to both pollution sources local or external and meteorological factors. Apportioned by Diagnostic ratios and Principal component analyses（PCA）, yearly potential sources of PM2.1- bound PAHs in Nanjing were traffic exhaust and coal consumption including coal combustion, coal gas production and coke oven. During autumn, local emission provided a higher level of contribution with the source of wood/biomass burning supplied. However, air masses in spring and winter were relatively aged and influenced more by long range transport. Particulates in summer were diluted by Asian monsoon with much degradation happened.

关键词： Concentration Polycyclic aromatic hydrocarbons Correlation sources

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中国电机工程学报 2023年第23期43卷 9010-9019页

作者：孔旭李跃波刘黎樊淑娴军事科学院国防工程研究院工程防护研究所河南省洛阳市471023 电力传输与功率变换控制教育部重点实验室(上海交通大学电气系) 上海市闵行区200240 山东科技大学电气与自动化工程学院山东省青岛市266590

文中对换流站中模块化多电平电压源型换流器(modularmultilevel converter,MMC)和混合式直流断路器中IGBT开关操作产生的瞬态电场进行实测,并分析其在设备状态在线监测中的应用。首先,证明换流站中开关瞬态电场属于准静态场,且与设备电... 详细信息

文中对换流站中模块化多电平电压源型换流器(modularmultilevel converter,MMC)和混合式直流断路器中IGBT开关操作产生的瞬态电场进行实测,并分析其在设备状态在线监测中的应用。首先,证明换流站中开关瞬态电场属于准静态场,且与设备电压之间存在线性关系,为基于开关瞬态电场状态监测方法提供理论基础。进一步,在舟定换流站人工短路试验中,对MMC高频电场波形和直流断路器开关瞬态电场脉冲进行实测。分析MMC不同工作状态下高频电场信号特征,特别发现高频电场信号中包含通过换流站自带录波系统不易测量的高次谐波信息。另一方面,发现基于开关电场脉冲的陡峭脉冲前沿,可测量MMC和直流断路器闭锁时刻,误差小于0.005ms。因此,基于瞬态电场测量方法可以在一定程度上弥补换流站自带录波系统测量带宽有限的缺点,补充系统高次谐波等运行信息,提高设备闭锁时刻测量精度,在MMC和高压直流断路器等设备在线状态监测中具有潜在应用价值。

关键词：在线状态监测瞬态电场环境混合式高压直流断路器高压直流输电模块化多电平换流器

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南京北郊冬季大气气溶胶及其湿清除特征研究

气候与环境研究 2009年第5期14卷 523-530页

作者：康汉青朱彬樊曙先南京信息工程大学南京210044

利用WPS(宽范围颗粒粒径谱仪)、雨滴谱仪和雾滴谱仪测量了2007～2008年冬季南京北郊大气气溶胶数浓度谱分布和降水强度,分析了气溶胶粒子的分布特征以及气溶胶粒径与湿清除系数的关系。结果表明:气溶胶粒子具有明显的双峰型日变化特征,... 详细信息

利用WPS(宽范围颗粒粒径谱仪)、雨滴谱仪和雾滴谱仪测量了2007～2008年冬季南京北郊大气气溶胶数浓度谱分布和降水强度,分析了气溶胶粒子的分布特征以及气溶胶粒径与湿清除系数的关系。结果表明:气溶胶粒子具有明显的双峰型日变化特征,数浓度主要集中在0.02～0.2μm粒径范围内,受汽车尾气排放、混合层高度变化以及颗粒物水平输送的影响较大。降雨、降雪和雾过程都对气溶胶粒子有不同程度的清除,降雨和浓雾对核模态和粗模态的气溶胶粒子的清除能力显著,降雪对粒径小于0.03μm的气溶胶粒子的清除能力较强。

关键词：气溶胶数浓度湿清除

利用WRF-Chem模式模拟分析人为气溶胶对台风Fitow(1323)强度及降水的影响

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大气科学 2017年第5期41卷 960-974页

作者：沈新勇姜晓岑柳笛祖繁樊曙先南京信息工程大学气象灾害教育部重点实验室/气候与环境变化国际合作联合实验室/气象灾害预报预警与评估协同创新中心南京210044 中国科学院大气物理研究所云降水物理与强风暴重点实验室北京100029 耶鲁大学-南京信息工程大学大气环境中心南京210044 江苏省气象科学研究所南京210009 南京信息工程大学中国气象局气溶胶与云降水重点开放实验室南京210044

利用气象与化学模块在线耦合的模式WRF-Chem V3.5(Weather Research and Forecasting Model coupled to Chemistry Version 3.5)对1323号台风Fitow进行了模拟,设计无人为排放源、含人为排放源和人为排放源增加的三组模拟试验,对比分析... 详细信息

利用气象与化学模块在线耦合的模式WRF-Chem V3.5(Weather Research and Forecasting Model coupled to Chemistry Version 3.5)对1323号台风Fitow进行了模拟,设计无人为排放源、含人为排放源和人为排放源增加的三组模拟试验,对比分析了人为气溶胶对台风的影响。结果表明:人为气溶胶对台风移动路径影响较小。人为气溶胶增加,台风强度减弱,台风主体总累积降水量减少,靠近陆地阶段台风主体降水率减少。气溶胶的增多可提供更多的凝结核,台风外围云水增加,更多的云水可上升至冻结层以上形成过冷水,促进冰相粒子的形成,释放的潜热增加,使外围对流增强,降水增加。台风外围对流的发展,使低层入流的暖湿空气更多的在外围上升,向台风中心的入流减弱,眼墙的发展减弱,降水减少,台风强度减弱。台风外围的对流发展弱于眼墙的对流,降水仍以眼墙区为主,使累积降水量和降水率整体上表现为减少。

关键词：台风强度降水人为气溶胶 WRF-Chem模式

南京冬季雾水金属元素及水溶性阴离子浓度特征

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环境科学学报 2009年第9期29卷 1878-1885页

作者：樊曙先杨雪贞樊韬韩锋黄红丽南京信息工程大学气象灾害省部共建教育部重点实验室南京210044 南京信息工程大学中国气象局大气物理与大气环境重点开放实验室南京210044 南京信息工程大学环境科学与工程学院南京210044 宁夏环境监测中心站银川750021

2007-11-15～2007-12-31期间在南京北郊南京信息工程大学设立采样点,对出现的6次浓雾过程进行了分时段雾水样品采集,并使用ICS-2000离子色谱仪和IRISIntrepidⅡ等离子体发射光谱仪测定了雾水中5种水溶性阴离子和14种金属元素浓度.结果表... 详细信息

2007-11-15～2007-12-31期间在南京北郊南京信息工程大学设立采样点,对出现的6次浓雾过程进行了分时段雾水样品采集,并使用ICS-2000离子色谱仪和IRISIntrepidⅡ等离子体发射光谱仪测定了雾水中5种水溶性阴离子和14种金属元素浓度.结果表明,南京6次浓雾过程雾水pH值在4.64～6.88之间;;水溶性阴离子平均浓度以SO24-最高(2864.9μmol·L-1),其次是Cl-(1584.4μmol·L-1)和NO3-(736·0μmol·L-1);;含量较高的金属元素有Ca、K、Na、Mg、Al和Zn;;雾水重金属元素Cu、Ni、Pb、Cd和Cr的平均浓度分别为2.30、1.46、0.42、0·41和0.37μmo·lL-1;;雾水金属元素浓度在雾的初始时段表现较高,随着雾的持续发展出现不同程度降低,但日出后的上班早高峰时段又出现很明显的升高;;雾水NO2-浓度值表现为夜间浓度较高而日出后浓度很低或消失,夜、昼变化非常大;;通过对比雾水和雨水pH平均值发现,雾水pH平均值是6.20,雨水pH平均值为4.91,小于酸雨指标值5.6,酸度较强;;雾水电导率是雨水的10.5倍,雾水的重金属元素Cd、Cr、Ni、Cu、Pb以及强致酸水溶性阴离子SO42-、NO3-、Cl-的浓度均远远高于雨水,说明雾区大气环境的污染程度比降雨天气更高.

关键词：雾水金属元素水溶性阴离子南京

气溶胶辐射效应在华东地区一次雾霾过程中的作用

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气象学报 2016年第3期74卷 465-478页

作者：张悦樊曙先李皓康博识南京信息工程大学大气环境与装备技术协同创新中心南京210044 南京信息工程大学大气物理学院南京210044 中国气象局气溶胶与云降水重点开放实验室南京信息工程大学南京210044

利用WRF/Chem(Weather Research and Forecasting Model coupled with Chemistry)模拟了2013年12月华东地区一次雾、霾事件气溶胶辐射反馈效应对气象场和大气质量的影响。通过3个不同气溶胶浓度设置的试验区分气溶胶浓度不同辐射效应的... 详细信息

利用WRF/Chem(Weather Research and Forecasting Model coupled with Chemistry)模拟了2013年12月华东地区一次雾、霾事件气溶胶辐射反馈效应对气象场和大气质量的影响。通过3个不同气溶胶浓度设置的试验区分气溶胶浓度不同辐射效应的影响。比较不同试验得出,本次雾、霾过程中,不论是气溶胶直接、半直接辐射效应还是间接效应均使污染地区短波辐射减少、2 m气温下降、大气边界层高度降低,不利于水汽与污染物的扩散,空气污染进一步加重,雾结构进一步稳定,并使雾的持续时间延长,发展高度更高;对于化学场来说,气溶胶直接、半直接辐射效应使污染地区PM_(2.5)浓度增大、消光系数增大、氮氧化物浓度增大,臭氧浓度降低;间接辐射效应使PM_(2.5)浓度和消光系数进一步增大,氮氧化物、臭氧浓度降低。综上所述,气溶胶辐射效应能使大气污染加重,并利于雾的发生、发展。

关键词：华东地区雾、霾气溶胶辐射效应

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复杂下垫面风电场风速数值模拟及误差特征

大气科学学报 2016年第5期39卷 672-682页

作者：祖繁樊曙先王咏薇吴息南京信息工程大学大气物理学院江苏南京210044 南京信息工程大学大气环境中心江苏南京210044

利用WRF模式分别对沿海及山地条件下风电场风速进行高分辨数值模拟,并对其误差特征进行分析,结果表明:1)WRF模式对复杂地形条件下的风速模拟性能良好,模拟值较好地体现天气尺度的周期变化;2)沿海及山地条件下模拟与观测的误差特征各不... 详细信息

利用WRF模式分别对沿海及山地条件下风电场风速进行高分辨数值模拟,并对其误差特征进行分析,结果表明:1)WRF模式对复杂地形条件下的风速模拟性能良好,模拟值较好地体现天气尺度的周期变化;2)沿海及山地条件下模拟与观测的误差特征各不相同。模式静态数据未能显现沿海的小岛,并且低估了山地测风塔所在的海拔,导致沿海平均模拟风速偏大,山地平均模拟风速偏小;3)分析不同风向的归一化均方根误差,沿海陆风情况下,下垫面相对复杂,误差明显增大;沿海海风情况下,下垫面均一,误差明显减小;4)仅作单个风电场周边数百平方千米的模拟,采用一台12核的服务器进行WRF模式的并行计算可满足48 h短期预测的时效性。仅仅提高模拟的网格分辨率,并不一定能提升模拟的准确性。

关键词：复杂下垫面 WRF模式风速数值模拟误差特征网格分辨率