检索结果-南通市图书馆

Development of an automatic measurement system using atmospheric pressure photoionization ultrahigh-resolution mass spectrometry and application for on-line analysis of particulate matter

引用

Journal of Environmental Sciences 2024年第4期138卷 516-530页

作者： Yayuan Dong Ranran Liu Ling Xie Xiaole Pan yele sun Lin Wu ZifaWang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Regional Atmospheric Environment Chinese Academy of SciencesInstitute of Urban EnvironmentXiamen 361021China

On-line chemical characterization of atmospheric particulate matter(PM)with soft ionization technique and ultrahigh-resolution Mass Spectrometry(UHRMS)provides molecular information of organic constituents in real *** we describe the development and application of an automatic measurement system that incorporates PM_(2.5)sampling,thermal desorption,atmospheric pressure photoionization,and UHRMS *** formulas of detected organic compounds were deducted from the accurate(±10 ppm)molecular weights obtained at a mass resolution of 100,000,allowing the identification of small organic compounds in PM_(2.5).Detection efficiencies of 28 standard compounds were determined and we found a high sensitivity and selectivity towards organic amines with limits of detection below 10 *** a proof of principle,PM_(2.5)samples collected off-line in winter in the urban area of Beijing were analyzed using the Ionization Module and HRMS of the *** automatic system was then applied to conduct on-line measurements during the summer time at a time resolution of 2 *** detected organic compounds comprised mainly CHON and CHN compounds below 350 m/*** seasonal variations in elemental composition were observed with shorter carbon backbones and higher O/C ratios in summer than that in *** result is consistent with stronger photochemical reactions and thus a higher oxidation state of organics in *** variation in signal intensity of each formula provides crucial information to reveal its source and formation *** summary,the automatic measurement system serves as an important tool for the on-line characterization and identification of organic species in PM_(2.5).

关键词： PM_(2.5) Chemical composition On-line measurement technique High resolution mass spectrometry

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Observation of Wind Shear during Evening Transition and an Estimation of Submicron Aerosol Concentrations in Beijing Using a Doppler Wind Lidar

引用

Journal of Meteorological Research 2017年第2期31卷 350-362页

作者： Yong CHEN Junling AN Xiquan WANG yele sun Zifa WANG Jing DUAN State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021 Chinese Academy of Meteorological Sciences Beijing 100081

The wind speed and direction measured over six months by a Doppler wind lidar（Windcube-8）were compared with wind cup anemometers mounted on the 325-m Beijing meteorological tower（BMT）.Five mountain–plain wind cases characterized by wind direction shear were selected based on the high-frequency（1.1 s）wind profile of the Windcube-8 and analyzed with 1-h mesoscale surface weather *** analyzed was the relationship between insitu PM_1（aerodynamic diameter≤1μm）concentrations measured at 260 m on BMT and the carrier-to-noise ratio（CNR）of the co-located *** results showed that the 10-min averaged wind speed and direction were highly correlated（R=0.96–0.99）at three matched levels（80,140,and 200 m）.The evening transition duration was1–3 h,with an average wind speed of 1 m s^（–1） at 80 m above the *** addition,there was a zero horizontalwind-speed zone along the wind direction shear line,and in one case,the wind speed was characterized by a Kelvin–Helmholtz gravity *** variability of the PM_1 concentrations was captured by the CNR of the Windcube-8 in a fair weather period without the long-range transport of dust.

关键词： mountain–plain wind wind shear wind lidar PM_1

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Growth Rates of Fine Aerosol Particles at a Site near Beijing in June 2013

引用

Advances in Atmospheric Sciences 2018年第2期35卷 209-217页

作者： Chuanfeng ZHAO Yanan LI Fang ZHANG yele sun Pucai WANG State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science Beijing Normal University Beijing 100875 China Joint Center for Global Change Studies Beijing 100875 China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100875 China

Growth of fine aerosol particles is investigated during the Aerosol-CCN-Cloud Closure Experiment campaign in June 2013 at an urban site near Beijing. Analyses show a high frequency （- 50%） of fine aerosol particle growth events, and show that the growth rates range from 2.1 to 6.5 nm h-1 with a mean value of - 5.1 nm h-1. A review of previous studies indicates that at least four mechanisms can affect the growth of fine aerosol particles： vapor condensation, intramodal coagulation, extramodal coagulation, and multi-phase chemical reaction. At the initial stage of fine aerosol particle growth, condensational growth usually plays a major role and coagulation efficiency generally increases with particle sizes. An overview of previous studies shows higher growth rates over megacity, urban and boreal forest regions than over rural and oceanic regions. This is most likely due to the higher condensational vapor, which can cause strong condensational growth of fine aerosol particles. Associated with these multiple factors of influence, there are large uncertainties for the aerosol particle growth rates, even at the same location.

关键词： growth rate fine aerosol particle Xianghe

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Aerosol characterization in a city in central China plain and implications for emission control

引用

Journal of Environmental Sciences 2021年第6期33卷 242-252页

作者： Zhijie Li Lu Lei Yanpei Li Chun Chen Qingqing Wang Wei Zhou Jiaxing sun Conghui Xie yele sun State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China

Extensive studies on aerosol chemistry have been carried out in megacities in China,however,aerosol characterization in Central China Plain(CCP)is *** we conducted real-time measurements of fine particle composition with a time-of-flight aerosol chemical speciation monitor in Kaifeng,Henan province in October *** results showed that nitrate and organics constituted the major fraction of non-refractory PM_(2.5)for the entire study,on average accounting for 34%and 33%,***,aerosol composition was substantially different among four periods due to different meteorological conditions and chemical *** instance,nitrate presented the lowest contribution during the first period due to evaporative loss associated with high temperature(T),and then rapidly increased during polluted periods as a function of relative humidity(RH).Positive matrix factorization analysis showed the dominance of secondary organic aerosol(SOA)in OA,and also the changes in OA composition under different T and RH *** addition,this study is unique with two periods of local emission *** trajectory and coefficient of divergence analysis showed that air pollution in CCP was overall homogeneously *** a result,the effectiveness of local emission controls in this region was strongly affected by meteorological conditions and regional *** found that one of the periods with emission control even showed the highest concentrations for the entire *** results point towards the limited effect of local emission controls in mitigating air pollution in CCP,and highlight the importance of joint emission controls under unfavorable meteorological conditions.

关键词： Central China plain Aerosol composition Sources Organic aerosol Emission control

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Long-term monitoring and source apportionment of PM_(2.5)/PM_(10) in Beijing,China

引用

Journal of Environmental Sciences 2008年第11期20卷 1323-1327页

作者： WANG Hailin ZHUANG Yahui WANG Ying sun yele YUAN Hui ZHUANG Guoshun HAO Zhengping Research Center for Eco-Environmental Sciences The Chinese Academy of Sciences Beijing 100085 China Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University Beijing 100875 China

During 2001-2006,PM2.5 (particle matter with aerodynamic diameter less than 2.5 microns) and PM10 (particle matter with aerodynamic diameter less than 10 microns) were collected at the Beijng Normal University (BNU) site,China,and in 2006,at a background site in Duolun (DL).The long-term monitoring data of elements,ions,and black carbon showed that the major constituents of PM2.5 were black carbon (BC) crustal elements,nitrates,ammonium salts,and *** five major components accounted for 20%-80% of...

关键词： PM2.5 PM10 monitoring source apportionment

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evolutionary processes and sources of high-nitrate haze episodes over Beijing,Spring

引用

Journal of Environmental Sciences 2017年第4期29卷 142-151页

作者： Ting Yang yele sun Wei Zhang Zifa Wang Xingang Liu Pingqing Fu Xiquan Wang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Aviation Meteorological Center of China Beijing 100021 China State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100089 China

Rare and consecutive high-nitrate haze pollution episodes were observed in Beijing in spring2012. We present detailed characterization of the sources and evolutionary mechanisms of this haze pollution, and focus on an episode that occurred between 15 and 26 April. Submicron aerosol species were found to be substantially elevated during haze episodes, and nitrates showed the largest increase and occupation（average： 32.2%） in non-refractory submicron particles（NR-PM1）, which did not occur in other seasons as previously reported. The haze episode（HE） was divided into three sub-episodes, HEa, HEb, and HEc. During HEa and HEc, a shallow boundary layer, stagnant meteorological conditions, and high humidity favored the formation of high-nitrate concentrations, which were mainly produced by three different processes —daytime photochemical production, gas-particle partitioning, and nighttime heterogeneous reactions — and the decline in visibility was mainly induced by ***, unlike HEa and HEc, during HEb, the contribution of high nitrates was partly from the transport of haze from the southeast of Beijing — the transport pathway was observed at ~800–1000 m by aerosol Lidar —and the decline in visibility during HEb was primarily caused by PM（2.5）. Our results provide useful information for air quality improvement strategies in Beijing during Spring.

关键词： Haze Nitrate Sources Lidar Aerosol Chemical Speciation Monitor Boundary layer

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nocturnal Low-levelWinds and Their Impacts on Particulate Matter over the Beijing Area

引用

Advances in Atmospheric Sciences 2018年第12期35卷 1455-1468页

作者： Yong CHEN Junling AN yele sun Xiquan WANG Yu QU Jingwei ZHANG Zifa WANG Jing DUAN State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth Science University of the Chinese Academy of SciencesBeijing 100049China Chinese Academy of Meteorological Sciences Beijing 100081China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

Three-month wind profiles, 260 m PM_1 concentrations [i.e., particulate matter(PM) with an aerodynamic diameter ≤1μm], and carrier-to-noise ratio data at two Beijing sites 55 km apart(urban and suburban) were collected to analyze the characteristics of low-level nocturnal wind and PM in autumn and winter. Three mountain-plain wind events with wind shear were selected for analysis. The measurements indicated that the maximum wind speeds of the northerly weak low-level jet(LLJ) below 320 m at the suburban site were weaker than those at the urban site, and the LLJ heights and depths at the suburban site were lower than those at the urban site. The nocturnal 140 m mean vertical velocities and the variations in vertical velocity at the urban site were larger than those at the suburban site. A nocturnal breeze with a weak LLJ of ～3 m s^(-1) noticeably offset nocturnal PM transport due to southerly flow and convergence within the northern urban area of Beijing. Characteristics of the nocturnal LLJ, such as start-up time, structure, intensity, and duration, were important factors in determining the decrease in the nocturnal horizontal range and site-based low-level variations in PM.

关键词： weak low-level jet wind direction shear wind lidar low-level PM1

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

城市边界层理化结构与大气污染形成机制研究进展

引用

科学通报 2018年第14期63卷 1374-1389页

作者：孙业乐中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室北京100029 中国科学院大学北京100049 中国科学院区域大气环境研究卓越创新中心厦门361021

自2013年《大气污染防治行动计划》实施以来,我国空气质量持续改善,但京津冀地区细颗粒物浓度仍远高于国家标准,秋冬季重污染天气仍时有发生.近些年,我国科学家在大气污染的立体探测、成因机制和来源解析、气溶胶和边界层相互作用等研... 详细信息

自2013年《大气污染防治行动计划》实施以来,我国空气质量持续改善,但京津冀地区细颗粒物浓度仍远高于国家标准,秋冬季重污染天气仍时有发生.近些年,我国科学家在大气污染的立体探测、成因机制和来源解析、气溶胶和边界层相互作用等研究领域取得重要进展,进一步支撑了我国大气污染的科学防治和重污染天气的有效应对,然而我国当前大气污染仍面临诸多科学难题.本文简要概述了我国近些年在大气污染垂直探测方面的一些研究进展,特别是依托于北京325 m气象塔建设的城市边界层理化结构探测平台,详细论述了北京地区不同季节大气气溶胶化学组分的垂直分布特征及其与边界层物理要素的相互作用,同时基于2014年亚太经合组织峰会(APEC)和2015年纪念抗日战争胜利70周年阅兵前后的垂直观测,阐明了大气污染化学组分对区域源排放控制的响应机制.本文还针对大气细颗粒物中的二次无机组分(硝酸盐和硫酸盐)和二次有机气溶胶的生成机制以及极端霾事件的生消机制的最新研究进展进行了评述,并在最后对大气污染监测、二次无机气溶胶生成机制和有机气溶胶的分子组成和物理化学属性(相态、挥发性和氧化态等)等未来研究给出了一些建议.

关键词：大气边界层理化结构大气污染二次气溶胶生成机制

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Development and evaluation of an online monitoring single-particle optical particle counter with polarization detection

引用

Journal of Environmental Sciences 2024年第4期138卷 585-596页

作者： Weijie Yao Xiaole Pan Yu Tian Hang Liu Yuting Zhang Shandong Lei Junbo Zhang Yinzhou Zhang LinWu yele sun Zifa Wang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

We developed a single-particle optical particle counter with polarization detection(SOPC)for the real-time measurement of the optical size and depolarization ratio(defined as the ratio of the vertical component to the parallel component of backward scattering)of atmospheric particles,the polarization ratio(DR)value can reflect the irregularity of the *** SOPC can detect aerosol particles with size larger than 500 nm and the maximum particle count rate reaches~1.8×10^(5)particles per *** SOPC uses a modulated polarization laser to measure the optical size of particles according to forward scattering signal and the DR value of the particles by backward S and P signal *** sampling rate of the SOPC was 106#/(sec·channel),and all the raw data were processed *** calibration curve was obtained by polystyrene latex spheres with sizes of 0.5-10μm,and the average relative deviation of measurement was 3.96% for sub 3μm particles.T-matrix method calculations showed that the DR value of backscatter light at 120°could describe the variations in the aspect ratio of particles in the above size *** performed insitu observations for the evaluation of the SOPC,the mass concentration constructed by the SOPC showed good agreement with the PM_(2.5)measurements in a nearby state-controlled monitoring *** instrument could provide useful data for source appointment and regulations against air pollution.

关键词： Instrument development Single particle detection Measurement uncertainty Optical simulation Mass concentration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Source apportionment for urban PM_(10) and PM_(2.5) in the Beijing area

引用

Chinese Science Bulletin 2007年第5期52卷 608-615页

作者： ZHANG Wei GUO JingHua sun yele YUAN Hui ZHUANG GuoShun ZHUANG YaHui HAO ZhengPing Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University Beijing 100875 China

Airborne particulate matter (PM2.5 and PM10) samples were collected at the Beijing Normal University sampling site in the urban area of Beijing, China in dry and wet seasons during 2001―2004. Concen-trations of 23 elements and 14 ions in particulate samples were determined by ICP-AES and IC, re-spectively. Source apportionment results derived from both Positive Matrix Factorization (PMF) and Chemical Mass Balance (CMB) models indicate that the major contributors of PM2.5 and PM10 in Beijing are: soil dust, fossil fuel combustion, vehicle exhausts, secondary particulate, biomass burning and some industrial sources. We have identified both regional common sources, such as vehicular emis-sions, particulate of secondary origin and biomass burning, as well as country-specific problems, such as sand storms and soil dust that should be addressed for effective air quality control.

关键词：北京地区城区空气颗粒物 PM10 PM2.5 污染源

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：