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191.
A low-cost, high throughput bioanalytical screening method was developed for monitoring cis/trans-permethrin in dust and soil samples. The method consisted of a simple sample preparation procedure [sonication with dichloromethane followed by a solvent exchange into methanol:water (1:1)] with bioanalytical detection using a magnetic particle enzyme-linked immunosorbent assay (ELISA). Quantitative recoveries (83–126 %) of cis/trans-permethrin were obtained for spiked soil and dust samples. The percent difference of duplicate ELISA analyses was within ± 20 % for standards and ± 35 % for samples. Similar sample preparation procedures were used for the conventional gas chromatography/mass spectrometry (GC/MS) analysis except that additional cleanup steps were required. Recoveries of cis/trans-permethrin ranged from 81 to 108 % for spiked soil and dust samples by GC/MS. The ELISA-derived permethrin concentrations were highly correlated with the GC/MS-derived sum of cis/trans-permethrin concentrations with a correlation coefficient (r) of 0.986. The ELISA method provided a rapid qualitative screen for cis/trans-permethrin in soil and dust while providing a higher sample throughput with a lower cost as compared to the GC/MS method. The ELISA can be applied as a complementary, low-cost screening tool to prioritize and rank samples prior to instrumental analysis for exposure studies.  相似文献   
192.
湿法净化黑烟中炭黑颗粒物的关键在于降低吸收液的表面张力并以高性能絮凝剂使其从溶液中絮凝、沉降以利于分离。选用十六烷基三甲基溴化胺(CTAB)为主要表面活性剂,使之与十二烷基苯磺酸钠(SDBS)和月桂醇聚氧乙烯(9)醚(AEO-9)进行复配实验,研究了复配液的表面张力,再向最低表面张力的复配表面活性剂溶液中投加絮凝剂聚合氯化铝(PAC)和聚丙烯酰胺(PAM),探讨絮凝剂的添加对黑烟颗粒沉降和絮凝的影响.实验结果表明:同时添加表面活性剂CTAB,SDBS和PAC,并使之浓度分别为0.5 mmol/L,0.4 mmol/L和200 mg/L时,炭黑颗粒的沉降效果最好,沉降率高达94%,且絮凝体较大,沉降时间仅为2 min。  相似文献   
193.
沙尘试验设备参数的测量,目前没有相关的标准和指导文件。本文给出沙尘试验设备参数测量的一般方法,主要介绍了一种沙尘浓度测量方法。  相似文献   
194.
介绍了侧吸导烟技术的技术背景,分析计算了焦炉装煤烟尘成分及含量,经对该技术的经济效益进行概算后显示,该技术可以有效改善焦炉区及周边环境,每年还可创造可观的经济效益,是一项值得研究推广的技术。  相似文献   
195.
针对经典除尘效率未考虑诸多随机因素影响的问题,提出了基于Monte-Carlo方法的效率分析模型,并通过实验数据验证其可靠性。通过该模型分析了粒径大小、电场气流速度、电晕电压、两极间距、粒子浓度等因素对收尘效率的影响规律,结果表明:基于Monte-Carlo方法的仿真结果精度更高,能有效预测静电除尘器的收尘效率,对于改进静电除尘器设计具有一定的理论意义和实用价值。  相似文献   
196.
新疆奎屯市17种落叶树种的滞尘能力研究   总被引:1,自引:0,他引:1  
对奎屯市17种落叶树种进行了滞尘能力测定。结果表明,不同类型植物滞尘能力差异显著,灌木滞尘能力大于乔木。在11种落叶乔木中,滞尘能力最强的是圆冠榆,平均滞尘能力达3.6894g/m^2;在5种落叶灌木中,滞尘能力最强的是玫瑰,平均滞尘量可达3.6581g/m^2。  相似文献   
197.
Human exposure to bioaccessible PCBs via indoor dust is limited around the world. In the present study, the workplace dust sample from commercial office, hospital, secondary school, shopping mall, electronic factory and manufacturing plant were collected from Hong Kong for PCBs analyses. Total PCBs concentrations ranged from 46.8 to 249 ng g−1, with a median of 107 ng g−1. Manufacturing plant showed the highest concentration among all of sampling sites. PCB 77 was found as the dominant congeners. The bioaccessibility of PCBs in small intestinal juice ranging from 8.3% to 26.0% was significantly higher than that in gastric condition, ranging from 4.8% to 12.4%. In addition, significant negative correlations (p < 0.05) were observed between KOW and bioaccessibility for all workplace dust samples. Risk assessment indicated that the averaged daily dose of dioxin-like PCBs via non-dietary intake of workplace dust, considering the bioaccessibility of PCBs, were much lower than the TDI of dioxins (2.3 pg WHO-TEQ kg bw−1 d−1) established by Joint FAO/WHO Expert Committee on Food Additives.  相似文献   
198.
本文对湿式脱硫除尘一体化设备的结构和性能进行了较为全面的分析,指出了该设备存在的诸多弊病,提出了解决方案--脱硫、除尘分体组合式的思路.  相似文献   
199.
河北省钢铁工业主要大气污染物减排潜力分析   总被引:1,自引:0,他引:1  
通过对河北省钢铁工业存在问题的分析,得出我省钢铁行业主要大气污染物为二氧化硫和粉尘.结合我省钢铁企业的实际情况,从工程技术、政策管理等方面提出相应治理措施,并对"十一五"期间我省钢铁行业二氧化硫和粉尘减排效益进行预测.预测结果显示:采用所建议的减排措施后,我省钢铁工业二氧化硫减排量对全省"十一五"减排计划的贡献率为81.4%;粉尘可减排60%.  相似文献   
200.
A new analytical method using accelerated solvent extraction was developed for the determination of 10 particle-associated polar and semipolar pesticides. In addition, six deuterated analogues of the target compounds were evaluated as internal standards. The method yielded acceptable accuracy (73–103% recovery) and precision (<25% relative standard deviation) for eight compounds. Using size exclusion chromatography (SEC) as cleanup step resulted in higher recoveries compared to solid phase extraction (SPE) cleanup.

Deuterated standards with 10 or more deuterium atoms performed well as internal standards concerning similar recovery and correlation with the target analytes.

The method was employed to extract particle-associated pesticides from 16 streams located in an area with intense agriculture in France. Acetochlor, pirimicarb, tebuconazole, fenpropidin, -endosulfan and chlorfenvinphos were detected at concentrations up to 1 mg kg−1 dry weight. A comparison with aquatic toxicity data indicated potential risk to the benthic fauna exposed to these concentrations of pirimicarb, -endosulfan and chlorfenvinphos.

We suggest that the method presented here be used for the extraction and quantitation of particle-associated polar pesticides.  相似文献   

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