中国科学院重庆绿色智能技术研究院机构知识库

PM2.5 samples were collected at Tsinghua University by SASS sampler in winter 2011. Heavy metals and water-soluble heavy metals of As, Cd, Cr, Cu, Mn, Pb and Zn, as well as water inorganic soluble ions were analyzed. The results indicated that the concentrations of water-soluble heavy metals were at high levels during the sampling period. The average concentrations of water-soluble heavy metals of As, Cd, Cr, Cu, Mn, Pb and Zn were 8.42, 3.18, 1.99, 7.84, 30.82, 49.27 and 412.81 ng/m3, respectively. The average concentrations of Cd and water-soluble As exceeded the National Proposed Standard of Ambient Air Quality Standard, more attention should be paid to these two elements. Water-soluble heavy metals were enhanced during heavily polluted episodes. Compared with non-haze and non-heating period, water-soluble As, Cd, Cr, Cu, Mn, Pb and Zn increased during haze days and heating period. The variations of water-soluble heavy metals tracked well with those of total heavy metals and PM2.5. The fractions of water-soluble heavy metals in total heavy metals were ≥50% for Zn and As; <20% and ≤50% for V, Mn, Se, Sr, Cd, Sb; and ≤20% for the rest elements. The water-soluble Zn contributing up to 66.8% of the total Zn was of particular concern due to its high concentration level and toxicity. The water-solubility of Cd, Mn and Pb was stable during different pollution conditions, whereas it was less stable for As, Cr, Cu and Zn. During the study period, the water-solubility of Cd, Cr, Cu, Fe, Mn, Pb and Zn increased as a function of neutralization ratio (NR), whereas, As showed an opposite trend.

于2011年冬季使用SASS采样器在清华大学采集PM_(2.5)样品,并对其中重金属和水溶性重金属(As、Cd、Cr、Cu、Mn、Pb和Zn等)以及无机离子进行了分析.结果表明,采样期间水溶性重金属浓度较高,As、Cd、Cr、Cu、Mn、Pb和Zn平均浓度依次为8.42,3,18,1.99,7.84,30.82, 49.27,412.81ng/m~3.Cd和水溶性As平均浓度超过《环境空气质量标准》中建议浓度限值.水溶性重金属在重污染期间易出现富集,灰霾和采暧期间As、Cd、Cr、Cu、Mn、Pb和Zn平均浓度都有增加趋势.水溶性重金属的逐日变化趋势与重金属和PM_(2.5)有较好的一致性.水溶性重金属在重金属中比重:50%≤Zn和As;20%