【作者】 王野；

【导师】 刘淼；

【作者基本信息】 吉林大学 ， 环境科学， 2012， 硕士

【摘要】 城市环境空气质量日趋恶化，大雾和阴霾现象日趋严重，人们已经深深的意识到了环境空气质量对于人类健康的重要性，改善环境空气质量已经迫在眉睫。重金属在环境空气中主要是以大气颗粒物的形式存在。空气中的重金属污染与水污染、土壤污染同样更难以治理，同时治理方法往往需要根据不同的污染情况而设计，并没有单一的解决方案。铅在环境中难于降解的有害物质，关于铅污染的问题难于处理，国际上也很重视。其污染主要特点具有毒害性、隐蔽性、长期性及不可逆性。因此对于环境空气中的特定金属污染物的测定和监测是十分必要的。铅在地壳中含量不大，自然界中存在很少量的天然铅，但含铅矿物聚集，熔点又很低（328℃），使铅在很早就被人们所利用了。铅对人体是有害的，空气中的铅主要是以尘，灰，烟等形式存在。国家制定了严格的标准，铅元素的分析方法有很多种，目前应用比较多的有火焰原子吸收法，ICP-AES法，离子选择电极溶出法，这些方法的影响因素较多，检数限高，而且往往需要用有机萃取浓缩等，费时费力且对人体健康有影响。为了提高环境空气中铅分析的灵敏度，本文主要研究氢化物发生原子荧光光度法快速测定空气中的铅含量的方法；大气颗粒物的采集方法选用中流量TSP采样器进行连续采样，每次样品的采样时间定为一小时，每天采集6次。采样点位的布设根据气象参数，选择合适具有代表性的点位进行布置。经比较选用硝酸-过氧化氢体系进行预处理；并比较不同的消解方法，选用微波消解法进行加热消解；改用新型玻璃纤维滤膜进行采样（减小滤膜的干扰）；通过标样、空白平行样及加标回收实验测试该方法的准确度与精密度；最后讨论了实验条件的影响因素，优化仪器参数等。本文对载流液的酸度大小对荧光强度的影响进行了讨论，在2%-2.5%效果最佳。并讨论了仪器的断续流动的进样速度对结果的影响，进样速度过快，氢气的产生量增多，导致氢化物的产生不稳定，影响测定的重现性；进样量过小，氢化物产生量少，荧光强度低，测定的结果偏低。更多还原

【Abstract】 City ambient air quality is exasperate with each passing day, fog and haze phenomenonis serious with each passing day, it has been deeply aware of the environmental air qualityfor the importance of human health, so it is imminently to improve the air quality of theenvironment． Heavy metals are existence in the form of atmospheric particles in theambient air． The heavy metals pollution in the air is more difficult to control as the waterpollution and soil pollution, at the same time management methods often need to bedesigned according to different pollution conditions and there is no single solution． Lead isa hazardous substance that difficult degradation in the environment, the world is alsoattached great importance on the lead pollution problems difficult to deal with． The maincharacteristics of the pollution are toxic, concealment, long-term and irreversible． So it isnecessary to determine and monitor the specific metal pollutants in the air．The lead content in the earth’s crust does not exist in nature; the lead has very smallamounts in the natural． But the lead mineral easily gathered, the melting point has a verylow degree (328), so lead is early used by people． Lead is harmful to the human body; leadin the air is primarily to dust, ash, smoke and other forms of existence． The country hasformulated strict standard, the analysis method of the lead elements has many kinds． Thepresent application more used with the flame atomic absorption method, ICP-AES method,ion selective electrode method of dissolution． These methods has many influencing factors,high check number limit, and often need to use organics extracting concentration, it is timeconsuming and impact on human health．In order to improve the sensitivity analysis of the environment of lead in the air, thispaper mainly studies the hydride generation atomic fluorescence photometric method forrapid determination of lead in the air content method; Atmospheric particulate mattercollection method in the selection of flow TSP sampler for the continuous sampling time,sampling time set for an hour every time, and collection six times a day． The sampling sitesare sited according to the meteorological parameters, and select the appropriaterepresentative point layout． After the comparison and selection, we choose the nitric acid and hydrogen peroxide system to treat with the pretreatment． And the comparison ofdifferent digestion methods, selection of microwave digestion method for heating． Use thenew glass fiber filter sampling to reduce the membrane interferences． Through the samples,blank parallel samples and recovery experiments to test the accuracy and precision of thismethod． Finally, it discussed the effect of experimental conditions on the factors andoptimal instrument parameters and so on．This article discussed the effects on the carrier liquid acidity size on the fluorescenceintensity, and has the conclusion that the effect is the best between the2%and2．5%． Italso discussed the apparatus for the intermittent flow injection speed on the results． Theinjection speed is too fast and the generation of hydrogen increases, which leads to thegeneration of unstable hydrides and influencing the measurement reproducibility． Thesample size is too small and the hydride is produced in small amounts, the fluorescenceintensity is low, which leads the results of the determination to be low．更多还原