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1.
水中多种酚类化合物同步提取方法研究   总被引:1,自引:1,他引:0  
对水中14种酚类化合物的液液萃取过程进行研究,选取不同萃取溶剂体系、水样pH和盐析条件等多个对萃取效率有决定性影响的参数进行优化。通过上述条件的优化选择,实现了同步对包括低沸点的苯酚、一氯代酚及较难提取的甲基酚和硝基酚等14种不同类型酚类化合物最优的萃取,提取效率达到75.2%~110.3%。  相似文献   

2.
建立了水中15种酞酸酯的液液萃取/固相萃取—气相色谱测定方法。就液液萃取探讨了萃取溶剂、萃取溶剂用量和水样pH值的影响,就固相萃取探讨了固相萃取柱、水样pH值和洗脱溶剂的影响。根据研究结果,确定液液萃取条件为调节pH至7,以二氯甲烷为萃取溶剂,萃取5 min;固相萃取条件为水样调节pH至7,经C18柱萃取后,以正己烷/丙酮混合溶剂(V∶V=5∶1)洗脱。测定15种酞酸酯类化合物的实际水样,液液萃取加标回收率为68%~128%,固相萃取加标回收率为65%~135%;液液萃取方法检出限为0.36~0.47μg/L,固相萃取方法检出限为0.20~0.39μg/L。  相似文献   

3.
建立了液液萃取-气相色谱法测定环境水样中邻苯二甲酸酯类化合物的方法。该方法能有效分离8种邻苯二甲酸酯类化合物。标准曲线线性回归相关系数均大于0.9999,最小检测量可达10^-11g,相对标准偏差为0.47%~1.83%。加标回收率为73.5%~114.6%。  相似文献   

4.
分散液液微萃取技术作为新型的样品前处理技术,由于其具有操作简便、费用低、富集倍数高等优点,已得到广泛认可和应用。文章综述了近5年来分散液液微萃取技术在环境金属离子分析中的进展,特别叙述了分析过程中的影响因素以及在环境分析中的应用,对此方法的原理作了简要介绍。  相似文献   

5.
建立了以环己烷为萃取剂、气相色谱法(氢火焰离子化检测器,FID)测定水质样品中可萃取性石油烃(C_(10)~C_(40))的分析方法。以正构烷烃混合标准溶液为定性和定量校准标准,以色谱峰面积总和与混合标准溶液总浓度建立校准曲线进行外标法定量。方法检出限为0.01 mg/L,经验证方法精密度和准确度良好。同时,分别以气相色谱法和红外光度法测定了地表水、污水处理厂出水、海水和化工废水等实际样品,对比实验结果表明,在可萃取性石油烃C_(10)~C_(40)的碳数范围内,气相色谱法的测试结果与红外光度法无明显差异,有较好的可比性。  相似文献   

6.
水中有机磷农药分析前处理方法探讨   总被引:5,自引:1,他引:4       下载免费PDF全文
分别采用液-液萃取、固相萃取前处理方法,提取水中10种常见的有机磷农药,对比了这两种提取方法的测定结果、经济成本、花费时间及对环境的影响,建议逐步用固相萃取法取代液?液萃取法提取水中有机磷农药。  相似文献   

7.
建立了液液萃取-气相色谱法测定水中15种硝基氯苯类化合物的方法。中性条件下,在水样中加入氯化钠,用环己烷进行萃取,得到方法检出限为0.019~0.044μg/L,在10.0μg/L~1.0 mg/L范围内线性良好,相关系数均0.999。加标水平为2.5μg/L时,空白水样加标回收率为74.8%~104%,相对标准偏差为4.79%~11.5%;实际水样加标回收率为69.1%~111%,相对标准偏差为5.83%~17.6%。方法适用于成分不复杂的实际水样中硝基氯苯类化合物的检测。  相似文献   

8.
高效液相色谱法测定水中7种三嗪类除草剂   总被引:1,自引:0,他引:1  
采用液液萃取和固相萃取两种方法预处理,高效液相色谱二极管阵列检测器测定水中7种三嗪类除草剂,选择了合适的检测波长和梯度淋洗条件。方法在0.100 mg/L~2.00 mg/L范围内线性良好,检出限为0.06μg/L~0.15μg/L,水样平行测定的RSD为1.6%~6.5%,加标回收率为95.0%~106%。  相似文献   

9.
气相色谱法同时测定水中28种多氯联苯单体   总被引:3,自引:0,他引:3  
采用液液萃取-浓硫酸磺化净化-气相色谱电子捕获检测器同时测定水中28种多氯联苯单体,必要时利用质谱选择离子监测模式定性,考察了萃取溶剂种类和体积及盐析效应对测定的影响,比较了硫酸磺化和弗罗里硅土柱对萃取液的净化效果。方法在1.00μg/L~47.6μg/L范围内线性良好,当取样体积为200 mL时,方法检出限为0.001μg/L~0.002μg/L,基体加标回收率为95.8%~103%,相对标准偏差≤18.7%。  相似文献   

10.
采用液液萃取-气质联用法同时测定水中20种农药类有机物。对前处理过程中萃取剂的选择、用量,萃取时间,盐析剂用量,有机改进剂的加入等条件进行了优化,使得各组分在0.500μg/L~50.0μg/L范围内线性良好。方法检出限为0.02μg/L~0.19μg/L;平行测定7次混合标准溶液,RSD为0.3%~9.1%;对20种农药类有机物混合标准溶液进行加标回收试验,回收率为90.5%~110%。该方法优化了《生活饮用水标准检验方法》( GB 5750-2006)中农药类有机污染物的检测方法,满足常规测定的要求。  相似文献   

11.
于桥水库浮游植物群落特征   总被引:4,自引:1,他引:3  
于桥水库是天津市惟一饮用水水源地,为了研究该水库浮游植物群落特征,于2012年春、夏、秋对于桥水库浮游植物进行了监测分析。结果表明:该水库共鉴定出绿藻(Chlorophyta)、蓝藻(Cyanophyta)、硅藻(Diatoms)、裸藻(Euglenophyta)、甲藻(Pyrrophyta)、隐藻(Cryptophyta)和黄藻(Xanthophyta)7门114种,群落组成以绿藻-硅藻门为主;浮游植物细胞密度具有明显的季节变化规律,表现为春季较低,夏季急剧增长,到了秋季又有所回落。优势种对于桥水库水质的评价结果表明,春季为中营养水体,夏季为富营养化水体,秋季为中富营养水体。春、夏、秋季于桥水库香农-韦弗多样性指数平均值分别为3.22、2.51和3.17,说明2012年于桥水库春季、秋季为贫营养水体,夏季为中营养水体,且有暴发水华的危险。  相似文献   

12.
The stem cuttings of the terrestrial, ornamental plant, Portulaca oleracea, grew well in distilled water by producing adventitious roots and leaves. However, when exposed to various concentrations of sulfate and nitrate salts of copper resulted in a suppression of root growth, increase in initiation time of roots and sprouts and decay of stem cuttings from the cut open end, decrease in number of leaves with an increase in concentration of copper in the growth medium. Accumulation of copper increased with increasing concentrations of both copper sulfate and copper nitrate. However, copper accumulation was greater in copper nitrate than in copper sulfate treatment. Hence, copper in the presence of nitrate is more toxic than in the presence of sulfate. The accumulation factors in all treatment concentrations were greater than 1, hence P. oleracea is a copper accumulator.  相似文献   

13.
分别在典型电子垃圾拆解区(E)和其参考区(S)采集了大气总悬浮颗粒物(TSP)样品,利用等离子体电感耦合质谱(ICP-MS)检测了13种元素。结果表明,E地区大气TSP中各元素含量均高于对照区,特别是污染元素Zn、Cu、Cd、Sn和Pb。E地区和S地区TSP中元素质量浓度的季节变化趋势相似,TSP中地壳元素质量浓度夏季高于冬季,而污染元素冬季高于夏季。E地区和S地区TSP中Cu、Zn、Sn和Pb的富集因子(EF)100,E地区EF值高于对照区,说明这些元素主要来源于电子垃圾处理过程;而Mg、K、Ca、Ti、V、Mn、Fe、Co和Cd的EF值为1~10,说明元素主要为自然来源。  相似文献   

14.
We evaluated exposure of aquatic biota to lead (Pb), zinc (Zn), and cadmium (Cd) in streams draining a Pb-mining district in southeast Missouri. Samples of plant biomass (detritus, periphyton, and filamentous algae), invertebrates (snails, crayfish, and riffle benthos), and two taxa of fish were collected from seven sites closest to mining areas (mining sites), four sites further downstream from mining (downstream sites), and eight reference sites in fall 2001. Samples of plant biomass from mining sites had highest metal concentrations, with means 10- to 60-times greater than those for reference sites. Mean metal concentrations in over 90% of samples of plant biomass from mining sites were significantly greater than those from reference sites. Mean concentrations of Pb, Zn, and Cd in most invertebrate samples from mining sites, and mean Pb concentrations in most fish samples from mining sites, were also significantly greater than those from reference sites. Concentrations of all three metals were lower in samples from downstream sites, but several samples of plant biomass from downstream sites had metal concentrations significantly greater than those from reference sites. Analysis of supplemental samples collected in the fall of 2002, a year of above-average stream discharge, had lower Pb concentrations and higher Cd concentrations than samples collected in 2001, near the end of a multi-year drought. Concentrations of Pb measured in fish and invertebrates collected from mining sites during 2001 and 2002 were similar to those measured at nearby sites in the 1970s, during the early years of mining in the Viburnum Trend. Results of this study demonstrate that long-term Pb mining activity in southeast Missouri has resulted in significantly elevated concentrations of Pb, Cd, and Zn in biota of receiving streams, compared to biota of similar streams without direct influence of mining. Our results also demonstrate that metal exposure in the study area differed significantly among sample types, habitats, and years, and that these factors should be carefully considered in the design of biomonitoring studies.  相似文献   

15.
中国1998年度环境质量状况   总被引:8,自引:0,他引:8  
对我国1998年度的环境空气质量,酸雨,主要流域水质,近岸域海水水质,地下水水位与水质,城市声环境、射环境质量,典型区域生态环境的状况进行了综述了与分析,指出了我国的环境污染问题主要是城市空气污染,地面水体污染和城市噪声污染。  相似文献   

16.
We examined the levels of cadmium, chromium, lead, manganese, mercury, and selenium in four species of birds near Sydney, New South Wales, Australia in January, 1996. Molted contour feathers were collected from silver gull, Larus novaehollandiae (Royal National Park and downtown Sydney), sulphur-crested cockatoo, Cacatua sulphurea (Blue Mountains, Royal National Park, and Sydney), Australian white ibis, Threskiornis molucca (Sydney), and rock dove Columba livia (Royal National Park and Sydney). We tested the null hypothesis that there were no species or locational differences in metal levels. There were significant species differences in all metals, with rock doves having the highest levels of cadmium, chromium, lead, and manganese, and silver gulls having the highest levels of mercury and selenium. Metal levels were generally low in cockatoos, and were lowest in those from the Royal National Park. For silver gulls, cadmium, lead, and chromium levels were highest at Sydney, and there were no locational differences in manganese, mercury, and selenium levels. For rock doves, cadmium, chromium and manganese were higher in Sydney, and there were no locational differences in lead, mercury, and selenium. Overall, cadmium and chromium levels were significantly higher in Sydney than in the Royal National Park for all species, and there were no locational differences in mercury levels. Although the levels of most metals in feathers from these Australian birds were within the ranges reported worldwide, lead levels in ibises and rock doves were among the highest reported worldwide, suggesting a cause for concern.  相似文献   

17.
钦州湾春季水质营养状况分析与评价   总被引:3,自引:1,他引:2  
根据2010年4月对钦州湾海域调查结果,分析并评价了该海域春季的营养状况。结果表明,表层海水中DIN和SiO3-Si都为茅尾海钦江入海口含量较高,PO4-P为茅尾海西南部沿岸增养殖区含量较高,DIN、PO4-P和SiO3-Si水平分布上均表现为湾内含量高于湾外。从营养结构看,与Justic等提出的营养盐化学计量限制标准比较,符合P限制条件,PO4-P可能成为浮游植物生长的潜在限制因子。根据营养状态指数评价模式和有机污染评价指数计算结果显示,2010年春季钦州湾海域营养水平属于中营养水平,有机污染程度属4级,表明钦州湾表层海水水质已达到中度污染。  相似文献   

18.
Portions of the Boulder River watershed contain elevated concentrations of arsenic, cadmium, copper, lead, and zinc in water, sediment, and biota. We measured concentrations of As, Cd, Cu, Pb, and Zn in biofilm and macroinvertebrates, and assessed macroinvertebrate assemblage and aquatic habitat with the objective of monitoring planned remediation efforts. Concentrations of metals were generally higher in downstream sites compared with upstream or reference sites, and two sites contained metal concentrations in macroinvertebrates greater than values reported to reduce health and survival of resident trout. Macroinvertebrate assemblage was correlated with metal concentrations in biofilm and macroinvertebrates. However, macroinvertebrate metrics were significantly correlated with a greater number of biofilm metals (8) than metals in invertebrates (4). Lead concentrations in biofilm appeared to have the most significant impact on macroinvertebrate assemblage. Metal concentrations in macroinvertebrates were directly proportional to concentrations in biofilm, indicating biofilm as a potential surrogate for monitoring metal impacts in aquatic systems.  相似文献   

19.
2008-2016年臭氧监测试点城市的臭氧污染特征   总被引:2,自引:0,他引:2  
选取臭氧试点城市北京、沈阳、上海和重庆,通过对2008-2016年臭氧监测数据进行分析研究,可以看出4个试点城市中北京的臭氧污染最严重。4个城市的臭氧污染特征均为高浓度臭氧所占比例较大,高值比较高,低浓度臭氧所占比例较小。北京、沈阳和上海的年平均臭氧浓度总体呈上升趋势。北京、上海、重庆、沈阳4个城市9年的超标天数比例分别为15.9%、7.7%、3.9%、6.5%。上海的臭氧浓度在秋季非常高。2012年的臭氧变化趋势比较异常,可能是由于2012年发生的不寻常气候条件导致。4个城市的臭氧浓度变化和气象条件的变化显著相关。  相似文献   

20.
合肥市环巢湖地区种植业面源污染监测与评价   总被引:1,自引:0,他引:1  
通过2016-2018年在合肥市环巢湖5个县区主要农田周边沟渠中采集水样,监测农田氮磷流失浓度,并评价该区域种植业面源污染状况。结果表明,这3年该区域种植业TN、TP流失的平均质量浓度分别为3.48 mg/L、0.602 mg/L,均高于地表水Ⅴ类水质标准。2016年与2017年TN、TP浓度差异不大,2018年较前两年TN浓度有所提高,TP浓度相比显著降低。巢湖市农田沟渠水中TP浓度高于其他县区,TN浓度相对较低;NO-3 N浓度庐江县高于其他县区;NH 3 N地区间几乎没有差异。TP和NH 3 N浓度均为秋季高于夏季,TN和NO-3 N浓度均为夏季高于秋季。  相似文献   

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