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1.
利用超声提取、固相萃取(SPE)净化和GC-MS技术对某市四个区的的果蔬基地7个土壤样品进行了土壤中持久性有机氯污染物分析.结果显示,土壤样品中主要有机污染物为γ-HCH、异狄氏剂和α-HCH,其中γ-HCH的检出率为100%,不同样品中γ-HCH和异狄氏剂差异明显,异狄氏剂和α-HCH检出率分别为86%和71.4%.  相似文献   

2.
用探头式超声波萃取仪、己烷/丙酮混合溶剂提取土壤中的15种Pops类有机氯农药(包括六氯苯、七氯、六六六、氯丹、艾氏剂、狄氏剂、异狄氏剂、灭蚁灵、滴滴涕),萃取溶液经氟罗里硅土柱净化、氮吹浓缩,用气相色谱/质谱仪(GC-MS)进行测定。方法检出限0.4~1.4μg/kg,空白样品有机氯农药加标回收率为52.8%~118%、有机氯标记替代物回收率为71.0%~122%,RSD为6.8%~16.5%。  相似文献   

3.
北京工业废水和城市污水中有机氯农药残留分析   总被引:2,自引:0,他引:2  
建立了基于HLB固相萃取柱和气相色谱-电子捕获(GC-ECD)测定水体中有机氯农药的方法,并对方法的回收率、灵敏度进行了评价,同时分析了北京市七类典型污染点源50个采样点位有机氯农药的浓度,检测到的有机氯农药包括γ-六六六、β-六六六、4,4’-滴滴涕、α-六六六、δ-六六六、硫丹Ⅰ、4,4’-滴滴伊、艾氏剂和异狄氏剂,它们的检出率分别为90%、60%、50%、46%、26%、8%、6%、2%和2%。主要有机氯农药污染残留为γ-六六六、β-六六六和4,4’-滴滴涕。检出有机氯农药浓度范围是0.20~76.40ng/L。方法对有机氯农药的回收率达到60.93%~141.50%,方法检测限为0.27~2.90ng/L。  相似文献   

4.
固相萃取-气相色谱法测定水中多种农药类内分泌干扰物   总被引:1,自引:0,他引:1  
建立了水样中用固相萃取小柱提取和净化、GC-ECD检测、GC-MSD定性证实的农药类内分泌干扰物检测方法,该方法样品提取、浓缩、净化步骤简便,能实现31种目标物同时检测。方法检测限0.05~0.50μg/L。添加回收率69%~101%,相对标准偏差低于10%。选择农药包括有机氯类(如滴滴涕、六六六、三氯杀螨醇、艾氏剂、异狄氏剂、狄氏剂、七氯、硫丹、氯丹等),氨基甲酸酯类(如甲草胺、乙草胺等),除虫菊酯类(如氯氰菊酯、速灭菊酯等)及其它农药(如氟乐灵、除草醚、毒死蜱)。该方法应用到测定某水库的水样,水库中31种农药类内分泌干扰物总浓度为48.8~890 ng/L,平均浓度295 ng/L。  相似文献   

5.
建立了高效液相色谱测定氯苯及其电催化降解中间产物对氯苯酚、对苯二酚、邻苯二酚、苯酚、反丁烯二酸的方法,优化了色谱条件.采用外标法定量,方法线性关系良好,RSD在0.3%~1.7%之间,加标回收率在90.5%~104%之间,适用于氯苯电催化降解过程的追踪测定.  相似文献   

6.
洞庭湖流域土壤中有机氯杀虫剂的残留规律研究   总被引:3,自引:1,他引:2  
2004年5月采集了洞庭湖流域45个土壤样品,用AES萃取技术,使用GC/MS方法测定了样品中的六氯笨、滴滴涕(DDTs)、氯丹、艾氏剂、狄氏剂、异狄氏剂、七氟和灭蚁灵.结果表明,六氯苯、滴滴涕的检出率为100%,氯丹和灭蚁灵的检出率很低,艾氏剂、狄氏剂、异狄氏剂和七氯未检出.总有机氯杀虫剂残留量平均值216.24μg/k,其中滴滴涕214.7μg/kg,占总OCPs的99.3%,且有些土壤样品中w(DDT)/w(DDE DDD)值较大,说明DDTs曾作为湘江流域的主要杀虫剂在洞庭湖流域土壤中广泛施用过,并且近期内仍然有输入.六氯苯的残留量虽然较低,但其施用范围广泛.总OCPs在棉田中的残留量很高,在茶场土壤中最低,表明棉田土壤曾因为各种原因施用过大量的有机氯杀虫剂,茶场土壤中有机氯农药的残存量处于安全范围.  相似文献   

7.
可替宁、可待因、1,7-二甲基黄嘌呤和咖啡因作为药物及其代谢产物广泛应用于日常生活中,其在环境中的残留物可能对人类健康和生态环境安全造成威胁。采用在线固相萃取法进行前处理,酸性条件(0. 1%甲酸水溶液)上样,水样加硫代硫酸钠(1 L水样加0. 1 g硫代硫酸钠)除去余氯后用高效液相色谱-串联质谱法测定饮用水中可替宁、可待因、1,7-二甲基黄嘌呤和咖啡因这4种兴奋剂。当进样体积为1. 0 m L时,方法检出限为0. 633~1. 75 ng/L,测定下限为2. 53~6. 98 ng/L,饮用水样品加标回收率为80. 0%~129%,多次测定均值的相对标准偏差(RSD)5%。方法检出限低,精密度和准确度好,能满足饮用水样品中4种兴奋剂的日常检测。  相似文献   

8.
基于污染指数与ArcGIS的聊城市耕地OCPs污染研究   总被引:1,自引:0,他引:1  
按8 km×8 km网格将聊城市耕地划分为136个采样点,调查六六六(BHCs)、滴滴涕(DDTs)、艾氏剂、狄氏剂、异狄氏剂、六氯苯和七氯等7种有机氯农药(OCPs)的残留状况。采用单因子污染指数和综合污染指数法进行污染评价,以此判断OCPs的污染程度。对7种OCPs在各样点中的含量进行差异分析,并应用ArcGIS8.3,以污染评价结果为数据支持,进行OCPs污染空间分布研究。结果表明,聊城市OCPs污染程度依次为DDTs>狄氏剂>七氯>艾氏剂>BHCs>异狄氏剂>六氯苯,总体变异程度依次为DDTs>狄氏剂>异狄氏剂>BHCs>七氯>六氯苯>艾氏剂。各OCPs空间分布没有固定的变化趋势;各采样点综合污染水平存在地域差异,以临清市污染最为严重,其他各县市污染较轻。  相似文献   

9.
采用动态固相微萃取技术富集水样中2-异丙基-3-甲氧基吡嗪、2-异丁基-3-甲氧基吡嗪、2-MIB、β-环柠檬醛、2,4,6-三氯苯甲醚、GSM、α-紫罗酮和β-紫罗酮等8种异味有机物,并用气相色谱质谱法测定。通过优化试验条件,使方法在2. 00 ng/L~100 ng/L范围内线性良好,方法检出限为1. 0 ng/L~4. 4 ng/L。空白水样3个质量浓度水平的加标回收率为81. 0%~121%,6次测定结果的RSD为1. 7%~8. 9%。将该方法用于一水库实际水样的测定,结果 2-MIB、β-环柠檬醛、α-紫罗酮和β-紫罗酮检出,其余均为未检出。  相似文献   

10.
利用超高效液相色谱-三重四极杆质谱建立了沉积物中6种溴代阻燃剂的分析方法,同时进行了采样分析。以正己烷-二氯甲烷(体积比1∶9)为萃取剂,在100℃下用加速溶剂萃取仪提取沉积物样品,循环3次。萃取液浓缩至2.0 m L,转移至净化柱,用150 m L正己烷-二氯甲烷(体积比1∶2)淋洗。将淋洗液浓缩至近干,加入内标物,定容至1 m L后,用液相色谱-三重四极杆准确定量。方法干重检出限为0.01~0.1 ng/g;替代标回收率为75.6%~98.9%,相对标准偏差为12.0%~13.0%;目标物回收率为70.5%~99.2%,相对标准偏差为2.1%~17.0%。研究区域水体沉积物中的三(2,3-二溴丙基)异氰脲酸酯浓度为未检出~0.14 ng/g,(2,4,6-三溴苯氧基)-1,3,5-三嗪浓度为未检出~0.14 ng/g,十溴二苯醚浓度为0.81~4.36 ng/g,六溴苯浓度为未检出~0.08 ng/g,表明沉积物中新型溴代阻燃剂浓度处于较低水平。  相似文献   

11.
洪泽湖沉积物中磷的形态研究   总被引:1,自引:0,他引:1  
采用改进的七步连续提取法对洪泽湖9个采样点沉积物中的各形态磷进行了分析,结果表明,所测洪泽湖沉积物中总磷(TP)含量范围为580.7~1 447.7 mg/kg,无机磷(IP)是TP的主要部分,占TP含量的64.32%~88.60%;有机磷(0P)占TP的11.40%~35.68%.受河流注入和人为活动的影响,TP、I...  相似文献   

12.
The occurrence and removal of eight endocrine disrupting compounds (EDCs), including estrone (E(1)), 17β-estradiol (E(2)), estriol (E(3)), 17α-ethinylestradiol (EE(2)), diethylstilbestrol (DES), bisphenol A (BPA), nonylphenol (NP) and octylphenol (OP), and their estrogenicities were investigated in a sewage treatment plant in Harbin city, China. The EDCs were extracted from wastewater samples by solid phase extraction (SPE) method and analyzed with gas chromatography coupled with mass spectrometry (GC-MS). The average concentrations in the influents and effluents ranged from 6.3 (EE(2)) to 1725.8 ng L(-1) (NP) and from 相似文献   

13.
采用C18固相膜萃取对地下水中15种多环芳烃进行富集净化,以二氯甲烷作洗脱溶剂,高效液相色谱法,荧光检测器测定。对萃取、浓缩和色谱条件进行优化,在1.ooixg/L~40.0μg/L范围内测定标准系列溶液并绘制标准曲线,相关系数R2〉0.999;15种多环芳烃的仪器检出限为0.4ng/L~3.0ng/L;对地下水样品加标,平均回收率在75.7%~96.7%之间;标准溶液平行测定7次的RSD为3.1%~11.9%。  相似文献   

14.
气相色谱法测定赤水河中段水体中14种有机氯农药的残留   总被引:1,自引:0,他引:1  
建立了用正己烷萃取,气相色谱—电子捕获(GC—ECD)测定水体中有机氯农药痕量残留的方法。结果表明:六氯苯、α-HCH、β-HCH、γ-HCH、δ-HCH、p,p′-DDD、p,p′-DDE、p,p′-DDT、艾氏剂、狄氏剂、异狄氏剂、七氯、环氧七氯、o,p′-DDT 14种农药在14 min内有较好的分离;2个不同浓...  相似文献   

15.
The aims were to assess the impact of a total smoking ban on the level of airborne contaminants and the urinary cotinine levels in the employees in bars and restaurants. In a follow up design, 13 bars and restaurants were visited before and after the implementation of a smoking ban. Ninety-three employees in the establishments were initially included into the study. The arithmetic mean concentration of nicotine and total dust declined from 28.3 microg m(-3) (range, 0.4-88.0) and 262 microg m(-3) (range, 52-662), respectively, to 0.6 microg m(-3) (range, not detected-3.7) and 77 microg m(-3) (range, not detected-261) after the smoking ban. The Pearson correlation coefficient between airborne nicotine and total dust was 0.86 (p < 0.001; n = 48). The post-shift geometric mean urinary cotinine concentration declined from 9.5 microg g(-1) creatinine (cr) (95% CI 6.5-13.7) to 1.4 microg g(-1) cr (95% CI 0.8-2.5) after the ban (p < 0.001) in 25 non-snuffing non-smokers. A reduction from 1444 microg g(-1) cr (95% CI 957-2180) to 688 microg g(-1) cr (95% CI 324-1458) was found (p < 0.05) in 29 non-snuffing smokers. The urinary cotinine levels increased from 11.7 microg g(-1) cr (95% CI 7.0-19.6) post-shift to 21.9 microg g(-1) cr (95% CI 13.3-36.3) (p < 0.01) in the next morning in 24 non-snuffing non-smokers before the smoking ban. A substantial reduction of airborne nicotine and total dust was observed after the introduction of a smoking ban in bars and restaurants. The urinary cotinine levels were reduced in non-smokers. The decline found in smokers may suggest a reduction in the amount of smoking after intervention. In non-smokers cotinine concentrations were higher based on urine sampled the morning after a shift than based on urine sampled immediately post-shift.  相似文献   

16.
PAH and PCB in soils of Switzerland--status and critical review   总被引:1,自引:0,他引:1  
The surface soil concentrations (0-20 cm) of the Swiss soil monitoring network (NABO) with 105 observation sites representing all major land use types ranged for the sum of 16 EPA PAH (PAH(16)) from 32 to 8465 microg kg(-1) (median 163 microg kg(-1)), for benzo[a]pyrene (BaP) from 0.5 to 1129 microg kg(-1) (median 13 microg kg(-1)) and for the sum of seven IRMM PCB (PCB(7)) from 0.5 to 12 microg kg(-1) (median 1.6 microg kg(-1)). The legal guide values of Switzerland were exceeded for PAH(16) at only three and for BaP at two sites. The PCB(7) concentrations were clearly below any assessment value. The concentration ranges were overlapping between all land use types. Tendencies for higher concentrations were observed at urban and viticulture sites. The overall measurement precision at repeatability conditions ranged from 1 to 37% RSD for PAH(16), BaP and PCB(7). The median bias for the chemical analysis was around zero for PAH(16), +5% for BaP and -5% for PCB(7) with spreads ranging from less than -20% up to more than +30%. The PAH profiles were clearly dominated by phenanthrene. Stratification by land use revealed a prevalence of benzo[a]pyrene at urban and naphthalene at conservation sites. For PCB, the general congener rank order was PCB no. 153 > 138 > 101 > 180. From a broad correlation screening only PAH(16)/BaP (r = 0.88**) were relevant for practical soil protection. The extensive comparison with other studies was severely biased by the lack of harmonisation, especially concerning sampling depth, sampling support, analytical method and the sum calculation procedure.  相似文献   

17.
The concentrations of total mercury (Hg) and methyl mercury (MMHg) were determined in 78 marine sediments in the Iranian coastal waters of the Persian Gulf along nine transects perpendicular to the coastline. Total Hg ranged from 10 to 56 ng g( - 1)d.w. and MMHg from 0.1 to 0.4 ng g( - 1) d.w. The fraction of methyl mercury accounted from 0.3% to 1.1% of the total mercury amount. The organic carbon (OC) content ranged from 0.4% to 1.8%. The present study indicates that the levels of Hg in the sediments of the Iranian coast of the Persian Gulf were all in the concentration range of unpolluted areas regarding Hg (<100 ng g( - 1)). The concentrations of total Hg, methyl mercury and organic carbon were generally higher in the deeper stations. Total Hg and MMHg were significantly correlated, but no significant correlations could be found between the Hg and OC levels.  相似文献   

18.
Mass concentrations and chemical components (18 elements, 9 ions, organic carbon [OC] and elemental carbon [EC]) in atmospheric PM(10) were measured at five sites in Fushun during heating, non-heating and sand periods in 2006-2007. PM(10) mass concentrations varied from 62.0 to 226.3 μg m(-3), with 21% of the total samples' mass concentrations exceeding the Chinese national secondary standard value of 150 μg m(-3), mainly concentrated in heating and sand periods. Crustal elements, trace elements, water-soluble ions, OC and EC represented 20-47%, 2-9%, 13-34%, 15-34% and 13-25% of the particulate matter mass concentrations, respectively. OC and crustal elements exhibited the highest mass percentages, at 27-34% and 30-47% during heating and sand period. Local agricultural residuals burning may contribute to EC and ion concentrations, as shown by ion temporal variation and OC and EC correlation analysis. Heavy metals (Cr, Ni, Zn, Cu and Mn) from coal combustion and industrial processes should be paid attention to in heating and sand periods. The anion/cation ratios exhibited their highest values for the background site with the influence of stationary sources on its upper wind direction during the sand period. Secondary organic carbon were 1.6-21.7, 1.5-23.0, 0.4-17.0, 0.2-33.0 and 0.2-21.1 μg m(-3), accounting for 20-77%, 44-88%, 4-77%, 8-69% and 4-73% of OC for the five sampling sites ZQ, DZ, XH, WH and SK, respectively. From the temporal and spatial variation analysis of major species, coal combustion, agricultural residual burning and industrial emission including dust re-suspended from raw material storage piles were important sources for atmospheric PM(10) in Fushun at heating, non-heating and sand periods, respectively. It was confirmed by principal component analysis that coal combustion, vehicle emission, industrial activities, soil dust, cement and construction dust and biomass burning were the main sources for PM(10) in this coal-based city.  相似文献   

19.
顶空便携式气相色谱—质谱仪现场测定地表水中苯系物   总被引:2,自引:0,他引:2  
对顶空便携式气相色谱—质谱仪分析水中的苯、甲苯、乙苯、邻-二甲苯、间-二甲苯、对-二甲苯、异丙苯的方法进行了研究,并讨论了平衡时间、平衡温度、水中含盐量等因素对测定的影响。结果表明,方法的回收率为94.15%~98.67%,相对标准偏差为2.32%~4.88%,最低检出限为0.031~0.094μg/L。该方法快速、准确、重复性好。  相似文献   

20.
Total suspended particle (TSP) collected at the fifth floor of House Dust in Hunan University, China, was analyzed in terms of microscopic morphology and chemical composition. The fine particles (50?nm-2?μm) in the TSP were analyzed by a high-resolution transmission electron microscope equipped with an energy-dispersive X-ray analyzer (HRTEM/EDS). Results showed that the particles were in shapes of plate, irregular and agglomerate. Based on EDS results, these fine particulate matter was primarily composed of Fe-rich (35.82-61.29%), Ca-rich (30.18-36.77%) and Si-rich (18.95-32.28%) particles. Other elements mainly including Mg (0.47-4.97%), Al (0.45-14.57%), S (0.45-4.73%), K (1.13-2.13%) and Zn (0.67-3.85%) were also observed. The sources analysis indicated that the HRTEM particles mainly originated from coal combustion, traffic emission, vehicles exhaust emission and fugitive soil or cement particulate matter. The coarse particles (4-50?μm) were detected by environmental scanning electron microscopy coupled with energy-dispersive X-ray detector (ESEM/EDS). Based on a simple algorithm, ESEM particles were categorized into five groups: C-bearing (46.15%, 67% and 86.98%), Si + Ca-bearing (21.48?+?11.80%, 16.51?+?10.81% and 16.32?+?10.62%), Si + Al-bearing (20.06?+?12.40%, 20.16?+?11.22% and 15.31?+?11.25%), Si-bearing (34.40%, 26.92% and 27.15%) particles and aggregates, most of which exhibit obvious crystalline structure, and these ESEM particles mainly derived from vehicles exhaust emission, coal combustion, soil, and biomass burning, while the aggregates are indicative of atmospheric reaction progress. HRTEM/EDS and ESEM/EDS are mutual complementary in analyzing the characteristic and determining the sources of TSP.  相似文献   

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