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31.
Li X Li P Yan L Chen J Cheng T Xu S 《Journal of environmental monitoring : JEM》2011,13(11):2988-2993
Atmospheric polycyclic aromatic hydrocarbons (PAHs) mainly originate from incomplete combustion or pyrolysis of materials containing carbon and hydrogen. They exist in gas and particle phases, as well as dissolved or suspended in precipitation (fog or rain). Current studies in atmospheric PAHs are predominantly focused on fog and rainwater samples. Some sampling difficulties are associated with fog samples. This study presented the first observation of the characteristics of PAHs in fog samples using a solid phase microextraction (SPME) technique. Eighteen fog samples were collected during ten fog events from March to December 2009 in the Shanghai area. PAHs were extracted by SPME and analyzed by gas chromatography-mass spectrometry (GC-MS). As the compounds were partially soluble in water, with solubility decreasing with increasing molecular weight, low molecular weight (LMW) PAH compounds were universally found in the fog water samples. Naphthalene (NaP), phenanthrene (Phe), anthracene (Ant) and fluoranthene (Flo) were dominant compounds in fog water. The total PAH concentration in fog water ranged from 0.03 to 6.67 μg L(-1) (mean of 1.06 μg L(-1)), and was much higher in winter than in summer. The concentration of PAHs in fog or rain water decreased after undergoing a pre-rain or pre-fog wash. The average concentration of PAHs was higher in fog than in rain. Diagnostic ratio analysis suggested that petroleum and combustion were the dominant contributors to PAHs in urban Shanghai. Backward trajectories were calculated to determine the origin of the air masses, showing that air masses were mostly from the northeast territory. 相似文献
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紫外检测—离子色谱法测定油田水中碘离子 总被引:3,自引:0,他引:3
本文研究了用阴离子交换分离,KCI溶液作为淋洗液,紫外/可见检测器在215nm波长处测定水中碘离子浓度的最佳离子色谱条件.该方法具有无干扰、灵敏度高、方法简便等特点,而且,在碘离子浓度为0.05—8.0μg·ml~(-1)范围内,其浓度与峰高的响应值之间存在良好的线性相关关系(相关系数大于0.999).碘离子的检出限为0.012μg·ml~(-1)(按信噪比等于3计算).其保留时间和峰高的相对标准偏差分别为2.6%和1.0%(n=7).方法用于基体复杂的油田水样中碘离子的测定,得到满意的结果,标准加入回收为98.4%. 相似文献
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Perchlorate in sewage sludge, rice, bottled water and milk collected from different areas in China 总被引:6,自引:0,他引:6
As a new emerging environmental contaminant, perchlorate has prompted people to pay more attention. The presence of perchlorate in the human body can result in improper regulation of metabolism for adults. Furthermore, it also causes developmental and behavioral problems for infants and children because it can interfere with iodide uptake into the thyroid tissue. In this paper, perchlorate in sewage sludge, rice, bottled drinking water and milk was detected for investigating the perchlorate pollution status in China. The places, where the samples were collected, cover most regions of China. Therefore, the final data on perchlorate levels will give an indication of the perchlorate pollution status in China. The final determination of perchlorate was performed by ion chromatography-electrospray tandem mass spectrometry with negative mode. The concentration of perchlorate in sewage sludge, rice, bottled drinking water and milk was in the range of 0.56-379.9 microg/kg, 0.16-4.88 mug/kg, 0.037-2.013 microg/L and 0.30-9.1 microg/L, respectively. The results show that perchlorate has been widespread in China. 相似文献
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迫于减排压力,继城镇生活污水处理厂的大规模建设运营后,全国各地又开始了一轮工业园区污水处理厂(公共污水处理系统)的建设热潮。本文对公共污水处理系统进水与排水执行标准存在的问题进行了分析,并提出了相应的对策与建议。 相似文献