大气环境中OH自由基测定

采用自旋捕集技术和电子自旋共振法结合测定大气环境中ＯＨ自由基，首先用自旋捕集剂将ＯＨ自由基捕集，生成比较稳定的自然旋加合物，，然后带回实验室处理测定，该法为开展大气光化学研究提供了一种采样方便，利于实测的方法，据３个采样点的实测结果表明，相对误差约为３５％，比文献所示结果略大。     

氨气敏电极法测定大气中氨

以Ｈ２ＳＯ４（０．０５ｍｏｌ／Ｌ）和ＮＨ３（１．００ｍｇ／Ｌ）的混合溶液作吸收液，采用气敏电极测定大气中氨，发挥了离子选择电极所具有的快速、灵敏及测定范围宽等优点，保证了大气中低浓度氨测定的准确性和可靠性。实验表明，该方法检测限为０．０１４～０．０１８ｍｇ／ｍ＾２，精密度约为１４．３％（相对标准偏差），回收率在９７％～１０２％之间，经６个月实验室验证的结果，无论是精密度的变异系数或回收率的置信系数     

“九五”至2010年上海大气环境监测系统规划设计

根据未来１５年上海的城市总体规划，结合环境保护的目标和主要任务，设计了包括监测项目、监测手段和监测网点在内的大气环境监测系统，以适应经济发展和环境管理的需要。     

大气环境中二硫化碳分析方法的选择研究

应用气相色谱Ｎｉ＾６３电子捕获检测器，在用６２０１红色担体为基体，涂１０％ＯＶ－１０１固定液的玻璃柱上，以甲苯作吸收液，对空气中ＣＳ２进行定量检测，其最低检出浓度可达０．００５ｍｇ／ｍ＾３，方法精密度好，ＳＯ２和Ｈ２Ｓ等不干扰测定，经现场实际测试，能适用于大气环境中微量ＣＳ２的分析。     

A review of atmospheric benzene homologues in China: Characterization, health risk assessment, source identification and countermeasures

Benzene homologues are important chemical precursors to the formation of ground-level ozone and secondary organic aerosol (SOA) in the atmosphere, in addition, some toxic species are harmful to human health. Strict countermeasures have been taken to fight air pollution since 2013, and total amount control of volatile organic compounds is being promoted in China at present. Therefore, it is important to understand the pollution situation and the control status of ambient benzene homologues in China. This paper reviews research progress from published papers on pollution characteristics, atmospheric photochemical reactivity, health risk assessment and source identification of ambient benzene homologues in recent years in China, and also summarizes policies and countermeasures for the control of ambient benzene homologues and the relevant achievements. The total ambient levels of benzene, toluene, ethylbenzene and xylenes (BTEX) shows a declining tendency from 2001 to 2016 in China. The mass concentrations of BTEX are generally higher in southern regions than in northern regions, and they present vertical decreasing variation characteristics with increasing altitude within the height range of about 5500 m. Toluene has the highest ozone formation potential and SOA formation potential both in urban areas and background areas, while benzene poses an obvious carcinogenic risk to the exposed adult populations in urban areas. Source identification of ambient benzene homologues suggested that local governments should adopt differentiated control strategies for ambient benzene homologues. Several recommendations are put forward for future research and policy-making on the control of ambient benzene homologues in China.     

Kinetic and mechanism studies of the ozonolysis of three unsaturated ketones

Reaction rate constants and products of 1-octen-3-one, 3-octen-2-one and 4-hexen-3-one with ozone were studied in a 100-L fluorinated ethylene propylene (FEP) Teflon film bag using absolute rate method at 298 ± 1 K and atmospheric pressure. The rate constants were (1.09 ± 0.12) × 10^?17, (3.48 ± 0.36) × 10^?17 and (5.70 ± 0.60) × 10^?17 cm³/(molecule?sec), respectively. According to the obtained rate constants, the effects of carbonyl were discussed. The carbonyl group in β position has a net withdrawing effect with respect to an olefinic bond, then causing the decline of rate constants. The quantum chemical calculation was used to explain the results of rate constants. The products of ozonolysis were mainly aldehydes, which have significant influence on the formation of SOA, and hence play an important role in the atmosphere. In this work, we detected the main products of reaction and proposed the reaction mechanism by combining the results of quantum chemical calculations. Atmospheric lifetime for three unsaturated ketones reacted with ozone was 36.4, 11.4 and 6.9 hr for 1-octen-3-one, 3-octen-2-one and 4-hexen-3-one, respectively.     

Watershed characteristics and climate factors effect on the temporal variability of mercury in the southern Baltic Sea rivers

Mercury(Hg) is a neurotoxic metal which can enter into the human organism mainly by fish consumption, skin and transpiration. In the coastal zone of the southern Baltic Sea, rivers are the main source of Hg. The Polish region represents the largest proportion of the Baltic Sea catchment and this research included four rivers of the Baltic watershed: the Reda,Zagórska Struga, Kacza and Gizdepka. The samples were collected in the years 2011–2013.Total and particulate Hg concentration in these rivers were measured. Due to intensive rain,deposited mercury on the catchment area was washed out into the riverines water and introduced into the Baltic Sea. Consequently, the load of Hg increased three times.Additionally, the intensive dry atmospheric deposition during heating season caused the increase of the concentration of particulate Hg in the river water even by 85%. The research confirmed the role of the river flow magnitude in the load of mercury introduced into the sea by rivers. Moreover, a high variability of mercury concentration was connected to the additional sources such as the chemicals containing Hg and no municipal sewage system.The analysis of stable isotopes indicated that the SPM contained terrestrial organic matter;however, there was no clear correlation between Hgtot, Corgand Ntotconcentrations and δ~(13)C, δ~(15)N, C/N in particulate matter.     

A preliminary analysis of the surface chemistry of atmospheric aerosol particles in a typical urban area of Beijing

Atmospheric aerosol particle samples were collected using an Ambient Eight Stage(Non-Viable) Cascade Impactor Sampler in a typical urban area of Beijing from 27 th Sep.to 5th Oct.,2009.The surface chemistry of these aerosol particles was analyzed using Static Time of Flight-Secondary Ion Mass Spectrometry(Static TOF-SIMS).The factors influencing surface compositions were evaluated in conjunction with the air pollution levels,meteorological factors,and air mass transport for the sampling period.The results show that a variety of organic ion groups and inorganic ions/ion groups were accumulated on the surfaces of aerosol particles in urban areas of Beijing;and hydrophobic organic compounds with short-or middle-chain alkyl as well as hydrophilic secondary inorganic compounds were observed.All these compounds have the potential to affect the atmospheric behavior of urban aerosol particles.PM1.1–2.1and PM3.3–4.7had similar elements on their surfaces,but some molecules and ionic groups demonstrated differences in Time of Flight-Secondary Ion Mass Spectrometry spectra.This suggests that the quantities of elements varied between PM1.1–2.1and PM3.3–4.7.In particular,more intense research efforts into fluoride pollution are required,because the fluorides on aerosol surfaces have the potential to harm human health.The levels of air pollution had the most significant influence on the surface compositions of aerosol particles in our study.Hence,heavier air pollution was associated with more complex surface compositions on aerosol particles.In addition,wind,rainfall,and air masses from the south also greatly influenced the surface compositions of these urban aerosol particles.     

Soil Zinc contamination from corrosion of galvanized structures

The present work relates to galvanized structures with several years of time life subjected to atmospheric corrosion, like galvanized high tension steel pylons. The mass and fate of zinc released is evaluated both via empirical and experimental procedures. The corrosion rate determination requested atmospheric condition characterization, especially for SO 2 concentration and experimental activities focused on soil sampling around pylons. The soil zinc content, total and exchangeable, is determinates by different analytical procedures. The zinc diffusion in environment and the zinc extension under the top soil is evaluated using 1-dimensional mathematical model for miscible species in porous soil.