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Journal of Environmental Sciences 2018年第7期30卷 33-40页

作者： Huiying Li Xiaofeng Huang Liming Cao Yuhong Zhai liwu zeng Lingyan He Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School

Water-soluble organic matter（WSOM） represents a critical fraction of fine particles（PM2.5）in the air, but its changing behaviors and formation mechanisms are not well understood yet, partly due to the lack of fast techniques for the ambient measurements. In this study,a novel system for the on-line measurement of water-soluble components in PM2.5, the particle-into-liquid sampler（PILS）–Nebulizer–aerosol chemical speciation monitor（ACSM）, was developed by combining a PILS, a nebulizer, and an ACSM. High time resolution concentrations of WSOM, sulfate, nitrate, ammonium, and chloride, as well as mass spectra, can be obtained with satisfied quality control results. The system was firstly applied in China for field measurement of WSOM. The mass spectrum of WSOM was found to resemble that of oxygenated organic aerosol, and WSOM agreed well with secondary inorganic ions. All evidence collected in the field campaign demonstrated that WSOM could be a good surrogate of secondary organic aerosol（SOA）. The PILS–Nebulizer–ACSM system can thus be a useful tool for intensive study of WSOM and SOA in PM2.5.

关键词： PM2.5 Water-soluble organic matter Secondary organic matter On-line measurement Mass spectrum

Characterization of submicron aerosols in the urban outflow of the central Pearl River Delta region of China

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Frontiers of Environmental Science & Engineering 2012年第5期6卷 725-733页

作者： Zhaoheng GONG Zijuan LAN Lian XUE liwu zeng Lingyan HE Xiaofeng HUANG Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China Qingdao Environmental Monitoring Center Qingdao 266003China Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control School of Environmental Sciences and EngineeringNanjing University of Information Sciences and EngineeringNanjing 210044China

Submicron aerosol particles （with aerody- namic diameters less than 1 pm, PM1） were sampled and measured in Heshan, an urban outflow site of Guangzhou megacity in Pearl River Delta in South China, using an Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer （HR-ToF-AMS） in November 2010 during 2010 Guangzhou Asian Games. The mean PM~ mass concentration measured was 47.9 ± 17.0 μg.m3 during the campaign, with organic aerosol （OA） and sulfate being the two dominant species, accounting for 36.3% and 20.9% of the total mass, respectively, followed by black carbon （17.1%, measured by an aethalometer）, nitrate （12.9%）, ammonium （9.6%） and chloride （3.1%）. The average size distributions of the species （except black carbon） were dominated by an accumulation mode peaking at -550 nm. Calculations based on high-resolution organic mass spectrum showed that, C, H, O and N on average contributed 58.1%, 7.3%, 30.7%, and 3.9% to the total organic mass, respectively. The average ratio of organic mass over organic carbon mass （OM/OC） was 1.73 ± 0.08. Four components of OA were identified by the Positive Matrix Factorization （PMF） analysis, including a hydro- carbon-like （HOA）, a biomass burning （BBOA） and two oxygenated （SV-OOA and LV-OOA） organic aerosol components, which on average accounted for 18.0%, 14.3%, 28.8% and 38.9% of the total organic mass, respectively.

关键词： organic aerosol high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) positive matrix factorization

Source apportionment of PM_(2.5)light extinction in an urban atmosphere in China

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Journal of Environmental Sciences 2018年第1期30卷 277-284页

作者： Zijuan Lan Bin Zhang Xiaofeng Huang Qiao Zhu Jinfeng Yuan liwu zeng Min Hu Lingyan He Key Laboratory for Urban Habitat Enuironmental Science and Technology School of Enuironment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China Shenzhen Research Academy of Environmental Sciences Shenzhen 518001China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

Haze in China is primarily caused by high pollution of atmospheric fine particulates（PM2.5）.However, the detailed source structures of PM2.5 light extinction have not been well established, especially for the roles of various organic aerosols, which makes haze management lack specified targets. This study obtained the mass concentrations of the chemical compositions and the light extinction coefficients of fine particles in the winter in Dongguan, Guangdong Province, using high time resolution aerosol observation instruments. We combined the positive matrix factor（PMF） analysis model of organic aerosols and the multiple linear regression method to establish a quantitative relationship model between the main chemical components, in particular the different sources of organic aerosols and the extinction coefficients of fine particles with a high goodness of fit（R^2= 0.953）. The results show that the contribution rates of ammonium sulphate,ammonium nitrate, biomass burning organic aerosol（BBOA）, secondary organic aerosol（SOA） and black carbon（BC） were 48.1%, 20.7%, 15.0%, 10.6%, and 5.6%, respectively. It can be seen that the contribution of the secondary aerosols is much higher than that of the primary aerosols（79.4% versus 20.6%） and are a major factor in the visibility decline. BBOA is found to have a high visibility destroying potential, with a high mass extinction coefficient, and was the largest contributor during some high pollution periods. A more detailed analysis indicates that the contribution of the enhanced absorption caused by BC mixing state was approximately 37.7% of the total particle absorption and should not be neglected.

关键词： Fine particles Organic aerosol Positive matrix factorisation Light extinction Multiple linear regression

Secondary organic aerosol formation from straw burning using an oxidation flow reactor

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Journal of Environmental Sciences 2022年第4期34卷 249-258页

作者： Hui Wang Song Guo Zhijun Wu Kai Qiao Rongzhi Tang Ying Yu Weizhao Xu Wenfei Zhu liwu zeng Xiaofeng Huang Lingyan He Mattias Hallquist State Key Joint Laboratory of Environmental Simulation and Pollution Control International Joint Laboratory for Regional Pollution ControlMinistry of Education(IJRC)College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science&TechnologyNanjing 10044China Key Laboratory for Urban Habitat Environmental Science and Technology College of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China Department of Chemistry and Molecular Biology Atmospheric ScienceUniversity of GothenburgSE-41296 GothenburgSweden

Herein,we use an oxidation flow reactor,Gothenburg:Potential Aerosol Mass(Go:PAM)reactor,to investigate the secondary organic aerosol(SOA)formation from wheat straw *** burning emissions are exposed to high concentrations of hydroxyl radicals(OH)to simulate processes equivalent to atmospheric oxidation of 0-2.55 *** volatile organic compounds(VOCs)were investigated,and particles were measured before and after the Go:PAM *** influence of water content(i.e.5%and 11%)in wheat straw was also *** burning stages,the flaming stage,and non-flaming stages,were *** particle emission factors(EFs)at a water content of 11%(~3.89 g/kg-fuel)are significantly higher than those at a water content of 5%(~2.26 g/kg-fuel)during the flaming ***,the water content showed no significant influence at the non-flaming *** of aromatics at a non-flaming stage(321.8±46.2 mg/kg-fuel)are larger than that at a flaming stage(130.9±37.1 mg/kg-fuel).The OA enhancement ratios increased with the increase in OH exposure at first and decreased with the additional increment of OH *** maximum OA enhancement ratio is~12 during the non-flaming stages,which is much higher than~1.7 during the flaming *** mass spectrum of the primary wheat burning organic aerosols closely resembles that of resolved biomass burning organic aerosols(BBOA)based on measurements in ambient *** results show that large gap(0%-90%)still remains to estimate biomass burning SOA if only the oxidation of VOCs were included.

关键词： Gothenburg:Potential Aerosol Mass(Go:PAM)reactor Wheat straw burning Flaming Non-flaming Secondary organic aerosol formation

微生物燃料电池与传统厌氧消化处理人工废水的比较

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应用基础与工程科学学报 2008年第1期16卷 23-28页

作者：陶虎春倪晋仁易丹曾立武林立北京大学深圳研究生院城市人居环境科学与技术重点实验室广东深圳518055 北京大学环境工程系水沙科学教育部重点实验室北京100871

通过微生物燃料电池(microbial fuel cell,MFC)与传统厌氧消化(conventional anaerobic digestion,CAD)的比较试验,考察了对高浓度葡萄糖和硫酸盐人工废水的处理效果.MFC在获得一定能量的同时(I=0.16mA,P=4.76mW/m^2),有效去除水中有机物,去除率高于CAD.葡萄糖为碳源,初始TOC=2100mg/L,运行144h,MFC获得91.61%去除率,CAD获得58.85%去除率;初始NH_3-N为500mg/L,MFC中去除率最高达92.61%,CAD达72.38%;MFC中对硫酸盐的利用率和CH_4产生量都低于CAD;比较结果表明,MFC技术可提高处理高浓度有机废水的效果.

关键词：微生物燃料电池传统厌氧消化人工废水处理

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基于TL494的臭氧发生器的研制

现代电子技术 2018年第16期41卷 1-4页

作者：曾立武兰紫娟黄晓锋何凌燕北京大学深圳研究生院环境与能源学院城市人居环境科学与技术重点实验室广东深圳518055 深圳市环境科学研究院广东深圳518001

臭氧污染已成为我国大气污染治理的重点与难点,臭氧监测也是我国环境空气质量监测系统中一项重要内容。为了更加灵活、便捷地标定臭氧监测仪,研制一种基于TL494双端式开关电源控制芯片的便携式臭氧发生器,经过一级标准的臭氧分析仪校正... 详细信息

臭氧污染已成为我国大气污染治理的重点与难点,臭氧监测也是我国环境空气质量监测系统中一项重要内容。为了更加灵活、便捷地标定臭氧监测仪,研制一种基于TL494双端式开关电源控制芯片的便携式臭氧发生器,经过一级标准的臭氧分析仪校正后,可方便对二级在线臭氧监测仪进行常规有效的浓度梯度检验。该发生器的基本原理为,通入设定流量的干空气进入到一个恒温腔体,腔体内使用185 nm紫外灯照射,使空气中的氧激发生成臭氧。通过调节紫外灯强度即可产生不同浓度的臭氧,输出用于后端应用。经实测验证,该发生器性能稳定,控制电压与发生浓度相关性可达0.999。

关键词：臭氧发生器 TL494 臭氧污染空气质量臭氧监测仪紫外灯

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胃癌新辅助化疗后的疗效评估研究进展

腹部外科 2023年第2期36卷 88-93页

作者：杜雨强曾利武张鹏华中科技大学同济医学院附属协和医院胃肠外科湖北武汉430022

术前新辅助化疗作为局部进展期胃癌的标准治疗模式之一,能有效提高R0切除率和降低肿瘤复发率。目前影像学技术、临床生物学以及病理学指标已广泛用于胃癌新辅助化疗后的疗效评估,可为指导个体化新辅助化疗提供依据。该文就胃癌新辅助化... 详细信息

术前新辅助化疗作为局部进展期胃癌的标准治疗模式之一,能有效提高R0切除率和降低肿瘤复发率。目前影像学技术、临床生物学以及病理学指标已广泛用于胃癌新辅助化疗后的疗效评估,可为指导个体化新辅助化疗提供依据。该文就胃癌新辅助化疗后的疗效评估研究进展进行了综述,以期为临床实践提供参考。

关键词：胃癌新辅助化疗疗效评估

深圳城市大气PM_(2.5)中金属元素的在线测量与来源特征

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环境科学学报 2019年第1期39卷 80-85页

作者：雷建容云龙苏翠平曹礼明曾立武黄晓锋北京大学深圳研究生院环境与能源学院城市人居环境科学与技术重点实验室，深圳 518055 深圳市环境监测中心站，深圳 518049

大气PM_(2.5)中很多金属元素危害人体健康,且具有源示踪性,因此,开展PM_(2.5)中金属在线监测对污染来源分析和大气污染防治有着重要意义.本研究于2017年4—5月使用美国Cooper环境空气多金属在线监测仪对深圳城市大气PM_(2.5)中金属元素... 详细信息

大气PM_(2.5)中很多金属元素危害人体健康,且具有源示踪性,因此,开展PM_(2.5)中金属在线监测对污染来源分析和大气污染防治有着重要意义.本研究于2017年4—5月使用美国Cooper环境空气多金属在线监测仪对深圳城市大气PM_(2.5)中金属元素进行连续观测.与同步离线采样测量的金属数据进行比对表明,10种元素(K、Zn、Cu、Mn、Fe、V、Ni、Ti、Pb、Cr)呈现良好的相关性,因而用于后续分析.观测期间大气PM_(2.5)的平均浓度24.8μg·m^(-3),其中10种金属元素总浓度为0.72μg·m^(-3),占比2.9%.Mn、Fe、Cu、Zn和Ti的浓度日变化显示了日间高、夜间低的特征,表明受到本地人为源的显著影响;而K、Pb、Cr浓度日变化无明显波动,说明受区域传输影响较大;Ni与V日变化趋势一致,主要来源为船舶排放.主成分因子分析结果表明,观测期间PM_(2.5)中金属污染来源主要为交通和扬尘源、工业排放/废物燃烧和船舶污染,方差贡献依次为54.3%、19.8%和8.8%.

关键词： PM_(2.5) 金属在线监测日变化主成分分析

华北地区夏季大气亚微米颗粒物的半挥发性特征

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环境科学研究 2015年第9期28卷 1345-1352页

作者：黄聪妮黄晓锋王少霞邵世云王晓飞曾立武何凌燕北京大学深圳研究生院环境与能源学院城市人居环境科学与技术重点实验室广东深圳518055 中国环境科学学会北京100082

利用热扩散管TD（Thermal Denuder）与高分辨飞行时间气溶胶质谱仪（HR-To F-AMS）联用法,于2013年6—7月对华北地区国家环境空气质量评价区域点香河的大气PM1（亚微米颗粒物）及其组分〔OM（有机质）、SO42-、NO3-、NH4＋、Cl-〕进行... 详细信息

利用热扩散管TD（Thermal Denuder）与高分辨飞行时间气溶胶质谱仪（HR-To F-AMS）联用法,于2013年6—7月对华北地区国家环境空气质量评价区域点香河的大气PM1（亚微米颗粒物）及其组分〔OM（有机质）、SO42-、NO3-、NH4＋、Cl-〕进行连续在线观测,并实现了PM1不同化学组分半挥发性特征的模拟分析.结果表明：在观测期间,ρ（PM1）平均值为（47.9±47.3）μg/m3,其中OM贡献最大,达到38.2%〔ρ（OM）占ρ（PM1）的比例,下同〕,之后依次为SO42-（33.7%）、NH4＋（13.8%）、NO3-（12.3%）、Cl-（2.0%）.在PM1的各化学组分中,NO3-和Cl-的MFR（质量剩余分数）值最低（约0.40）,表明二者的半挥发性最高,当温度为50℃时,约60%的NO3-或Cl-进入气相中;SO42-的半挥发性最低,在50℃时仍有约90%的质量剩余;而OM和NH4＋的半挥发性居中.NO3-的半挥发性受大气PM1污染水平的影响,50℃时其半挥发性随着ρ（PM1）的增加而升高.当温度从50℃升至200℃时,残留有机气溶胶的O/C（原子数比）从0.47增至0.60,说明半挥发性组分多为氧化态较低的有机化合物.此外,真空动力学粒径在60～2 000 nm的颗粒物在不同粒径段表现出相近的半挥发性.大气PM1半挥发性的定量分析结果可为全面认识大气颗粒物的物化性质及污染机理提供数据,也有助于空气质量模型的完善.

关键词： PM1(大气亚微米颗粒物) 气溶胶质谱半挥发性有机气溶胶华北地区

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深圳市大气能见度与细粒子浓度统计模型

应用气象学报 2009年第2期20卷 252-256页

作者：林云孙向明张小丽黄晓锋何凌燕曾立武北京大学深圳研究生院城市人居环境科学与技术实验室深圳518055 深圳市气象局深圳518040

利用深圳市2007年全年逐时能见度、PM2.5质量浓度和相对湿度观测数据,在分析大气消光机理及其影响因素的基础上确立了能见度与PM2.5之间的基本模型关系,着重讨论分析了相对湿度对颗粒物消光影响的常见修正方式,并通过线性和非线性回归... 详细信息

利用深圳市2007年全年逐时能见度、PM2.5质量浓度和相对湿度观测数据,在分析大气消光机理及其影响因素的基础上确立了能见度与PM2.5之间的基本模型关系,着重讨论分析了相对湿度对颗粒物消光影响的常见修正方式,并通过线性和非线性回归分析筛选相对湿度影响修正因子fRH的表达形式和确定模型参数,最终建立起适合于深圳本地情况的能见度与PM2.5之间的最优统计模型(R2=0.43,n=8024)。进一步利用能见度与PM2.5的日平均值进行了多元回归分析,模型拟合值与实测值之间的相关系数(R2)高达0.73(n=350),而且预测偏差范围小,较好地反映了深圳市大气能见度与PM2.5之间的定量相关关系。

关键词：能见度消光系数相对湿度多元回归