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1.
半渗透膜采样技术在有机污染物监测中的作用   总被引:6,自引:1,他引:6       下载免费PDF全文
介绍了半透膜装置的组成和特点、半渗透膜采样技术的优点及其在有机污染物监测中的应用,指出该技术可用于研究有机污染物在空气、生物、水体中的分布和迁移规律,以及与有机污染物相关的生态毒理实验。  相似文献   

2.
介绍了我国水环境有机物分析中常用的前处理技术,包括液液萃取、树脂吸附、固相萃取、固相微萃取、液膜萃取、半透膜被动采样、顶空、吹扫-捕集等,归纳了各种方法的原理、应用及优缺点,并对环境中有机污染物前处理技术的发展方向进行了展望。  相似文献   

3.
应用新型半透膜采样技术(SPMD),监测某城市污水处理流程中8个点污水中两类难降解有毒有机污染物多氯联苯(PCB)和多环芳烃(PAH),同时同地采集水样,气相色谱质谱联机,选择性离子扫描方式对各PCB异构体和PAH定性定量。与水样液液萃取相比,SPMD采样技术显著提高了分析的准确度。根据测定的采样器中污染物浓度,推算采样期间该点污水中的平均浓度,与瞬间水样分析结果符合程度较好。半透膜采样方法可用于污水处理工艺流程中多氯联苯和多环芳烃污染物的定性和半定量监测  相似文献   

4.
总结了半透膜被动采样器(SPMDs)、极性有机化合物整合采样器(POCIS)、化学捕收器(Chemcatcher)和硅橡胶被动采样器(Silicon rubber)几种常用被动采样器的结构组成、应用模型、原理、样品的前处理、影响因素及应用范围,指出几种被动采样技术应用上存在的问题,并对其应用前景进行总结和展望。  相似文献   

5.
我国环境中有机污染物分析方法及痕量富集技术的进展   总被引:10,自引:8,他引:10  
综述了我国环境中有机污染物的分析方法和痕量富集技术,介绍了吹扫-捕集法、固相微萃取技术、固相萃取技术、半渗透膜采样技术与分析仪器联用在有机污染物测定中的应用情况。  相似文献   

6.
PUF大气被动采样技术对POPs的采样计算   总被引:2,自引:0,他引:2  
随着《斯德哥尔摩公约》的实施,大气中持久性有机污染物(POPs)的大气被动采样(PAS)观测技术得到了快速发展,相比于传统大气主动采样技术,PAS技术具有明显的优势。以应用最为广泛的聚氨酯软性泡沫材料大气被动采样(PUF-PAS)为例,重点阐述和讨论了3种通过大气被动采样技术来计算污染物在空气中的浓度的方法,并对其采样原理和发展趋势进行了简要介绍。  相似文献   

7.
利用Triolein半渗透膜采样技术测定洋河水中的优先污染物   总被引:6,自引:0,他引:6  
应用Triolein半渗透膜采样器采集了河北洋河宣化至官厅水库河段水样,根据测定采样器中多氯联苯污染物(PCBs)及其它优先污染物浓度,可以估算这些污染物在河段水体中的平均浓度。将结果与同时同地采集的水样,经萃取浓缩后分析得到的结果比较,发现对于不同类型污染物,二者符合程度不同。本研究证明半渗透膜被动采样技术可用于水中多氯联苯等难降解污染物的定量监测,有可能在我国的优先污染物监测工作中发挥作用  相似文献   

8.
利用 Triolein 半渗透膜采样技术 ( Triolein SPMD)采集了淮河信阳、淮南断面水样 ,测定了采样器中多氯联苯、多环芳烃、取代苯等有毒有机污染物浓度。污染物在 SPMD酯中高浓度富集 ,使其定性和定量更加容易和准确。根据SPMD酯 水分配平衡理论 ,进一步估算得到目标污染物在水中的平均浓度。本研究证明 Triolein SPMD技术可用于水中多氯联苯、多环芳烃、取代苯等污染物的采集和定量分析 ,可在我国的优先污染物监测、控制工作中发挥作用。  相似文献   

9.
我国固体废物监测技术发展现状   总被引:1,自引:0,他引:1  
简述了我国固体废物环境管理和监测框架体系,回顾了固体废物监测的发展历史,并从采样和制样、浸出毒性的浸出方法、无机污染物和有机污染物测定方法等方面对固体废物监测现状进行了总结。针对固体废物监测体系存在的问题,提出了对采样技术开展更新性研究,尽快将已有的测定方法标准化并建立总量监测方法,开发各类污染物的形态分析方法,以及规范废弃物危险特性试验方法等建议。  相似文献   

10.
大气中半挥发性有机污染物的监测研究进展   总被引:1,自引:0,他引:1       下载免费PDF全文
介绍了大气中半挥发性有机污染物的采样方法和气/固相分配模型,综述了索氏提取、超声波萃取、超临界流体萃取、微波萃取、固相微萃取等样品预处理方法,以及直接进样热解析和其他仪器分析方法,对大气中半挥发性有机污染物的监测研究进展作了展望。  相似文献   

11.
Lipid-filled semipermeable membrane devices (SPMDs) are receiving increasing attention as passive, in situ samplers for the assessment of environmental pollutant exposure. Although SPMDs have been successfully used in a variety of field studies in surface waters, only a few studies have addressed their characteristics as groundwater samplers. In this study, the performance of the SPMDs for monitoring organic contaminants in groundwater was evaluated in a pilot field application in an area severely contaminated by chemical waste, especially by chlorinated hydrocarbons. The spatial distribution of hydrophobic groundwater contaminants was assessed using a combination of passive sampling with SPMDs and non-target semiquantitative GC-MS analysis. More than 100 contaminants were identified and semiquantitatively determined in SPMD samples. Along the 6 field sites under investigation, a large concentration gradient was observed, which confirms a very limited mobility of hydrophobic substances in dissolved form in the aquifer. The in situ extraction potential of the SPMD is limited by groundwater flow, when the exchange volume of well water during an exposure is lower than the SPMD clearance volume for the analytes. This study demonstrates that SPMDs present a useful tool for sampling and analyzing of groundwater polluted with complex mixtures of hydrophobic chemicals and provides guidance for further development of passive sampling technology for groundwater.  相似文献   

12.
Continuous, intermittent and passive sampling of airborne VOCs   总被引:1,自引:0,他引:1  
Long sampling periods are often advantageous or required for measuring air quality and characterizing exposures. However, sampling periods exceeding 8 to 24 h using thermally desorbable adsorbent tube (TDT) samplers for the measurement of airborne volatile organic compounds (VOCs) face several challenges, including maintaining stable and low flow rates, and avoiding breakthrough of the adsorbent. These problems may be avoided using intermittent sampling; however, the literature contains few if any reports that have evaluated this technique in environmental, occupational or other applications. The purpose of this study is to evaluate continuous, intermittent and passive sampling methods using both laboratory and real-world tests. Laboratory tests compared continuous and intermittent (active) samplers in a controlled dynamic test gas generation system. Field tests used side-by-side active and passive samplers in an office, home workshop and four smokers' homes. All samples were analyzed for a wide range of VOCs by GC-MS. In most instances, intermittent sampling yielded better reproducibility (duplicate precision of 10 +/- 6%) than continuous low-flow sampling (18 +/- 5%), in part due to difficulty maintaining low flows. Concentrations obtained using intermittent sampling agreed with those for continuous sampling, with downward biases resulting primarily from errors in flow rate measurements. In the field, more VOC species were detected using active rather than passive sampling. Passive measurements were 12% lower than continuous measurements, a difference attributed to declining uptake rates at higher concentrations over the 3 to 4 d sampling period. Overall, most measurements obtained using the three sampling methods agreed within 20% for a wide range of concentrations (0.1 to 230 microg m(-3)). Both passive and intermittent sampling approaches are suitable for long sampling periods, but intermittent sampling provides greater flexibility with respect to sampling period, and permits the use of multi-bed adsorbents that can capture a wider range of VOCs.  相似文献   

13.
A rapid, empirical method is described for estimating weekly AOT40 from ozone concentrations measured with passive samplers at forest sites. The method is based on linear regression and was developed after three years of measurements in Trentino (northern Italy). It was tested against an independent set of data from passive sampler sites across Italy. It provides good weekly estimates compared with those measured by conventional monitors (0.85 ≤R(2)≤ 0.970; 97 ≤ RMSE ≤ 302). Estimates obtained using passive sampling at forest sites are comparable to those obtained by another estimation method based on modelling hourly concentrations (R(2) = 0.94; 131 ≤ RMSE ≤ 351). Regression coefficients of passive sampling are similar to those obtained with conventional monitors at forest sites. Testing against an independent dataset generated by passive sampling provided similar results (0.86 ≤R(2)≤ 0.99; 65 ≤ RMSE ≤ 478). Errors tend to accumulate when weekly AOT40 estimates are summed to obtain the total AOT40 over the May-July period, and the median deviation between the two estimation methods based on passive sampling is 11%. The method proposed does not require any assumptions, complex calculation or modelling technique, and can be useful when other estimation methods are not feasible, either in principle or in practice. However, the method is not useful when estimates of hourly concentrations are of interest.  相似文献   

14.
A new all season passive sampling system for monitoring O3 in the atmosphere has been developed in the laboratory and validated in the field. The unique features for this system include a newly designed passive sampler and a rain shelter, which allow the passive sampler to be installed in the field facing downwards. An equation associated with meteorological parameters is used to calculate the passive sampling rates. This system has been extensively tested in the lab (temperature from –18 to 20°C, relative humidity from 13 to 81%, and wind speed from 0.5 to 150 cm/s) and validated in the field in climates of all seasons. The accuracy of the ozone concentrations in the atmosphere obtained with the use of the new passive sampling system was higher than 85% compared to those obtained with continuous ozone analyzers. The new ozone passive sampling system can be used to measure ambient O3 concentrations ranging from 3 ppb to 1000 ppb based on one-day exposure and 0.1 ppb to 140 ppb for a monthly exposure period. It is also reasonable to conclude that the new passive sampling system can be used for eight-hour exposure study because of the low field blanks and high sampling rates.  相似文献   

15.
A passive sampler has been developed and is demonstrated in situ for urban runoff. The passive sampler is compared to conventional composite (time-dependent and flow-weighted) bottle sampling during and between storm events. The sampling was carried out at established stormwater stations; before and after a stormwater detention pond. In situ deployment of the passive sampler provides the metal concentrations, corresponding to the electrochemically available fraction of total metal, for time-dependent samples collected in parallel. The sampler provides improved accuracy compared to bottle sampling because contamination during sample transport and handling is minimised. Laboratory handling is reduced by direct analysis of the accumulated metals on the receiving membrane by laser ablation inductively coupled plasma mass spectrometry. Passive sampling also solves the problem of metal speciation change during transport to the laboratory, which is a potential problem for bottle samples. The low cost and convenience of the passive sampler and subsequent analysis should allow significantly more extensive spatial and temporal monitoring of metals in the aquatic environment than has previously been possible.  相似文献   

16.
汞的测试技术包括采样和分析两部分,其中汞含量的分析方法已经相对比较成熟,限制测试技术发展的诸多问题主要来源于取样过程。根据不同的取样方式,将现有测试技术分为湿式采样分析法、干式采样分析法以及在线分析技术3种,重点介绍了3种方法的采样原理、系统构成、过程的影响因素以及适用范围。最后针对CVAAS、CVAFS、AES 3种汞含量测定技术在Hg CEMS测试系统中的应用进行了对比介绍。  相似文献   

17.
Styrene-7,8-oxide (SO) is generated at low concentrations from the oxidation of styrene during the processing of reinforced plastics. Since exposure to SO has important health implications, we developed air sampling and analytical methods to measure low levels of airborne SO in the presence of styrene and its other oxidation products, namely phenylacetaldehyde (PAA) and acetophenone (AP). Both active and passive air monitors were used. The active sampling method, which employed adsorption on Tenax, was suitable for measuring SO, PAA and AP but had limited capacity for styrene due to breakthrough. The passive monitor employed a carbon adsorbent and was suitable for measurement of styrene and SO but not PAA and AP due to poor recovery. After sampling, the analytes were extracted from the adsorbents with ethyl acetate and measured by gas chromatography with flame ionization detection or mass spectrometry. By maintaining the injection port at 70 degrees C, the thermal rearrangement of SO to PAA was minimized. Recovery of styrene and SO from the passive monitor depended upon loading and was corrected by linearization of the Freundlich isotherm. The limits of detection for SO, PAA, and AP were 0.2 ppb using the active monitor, and for SO was 1 ppb using the passive monitor. The sampling precision for SO (RSD from personal measurements) was 5.0% for the passive monitor and was 13.4% for the active monitor over a range of exposures from 5-150 ppb. The corresponding precision for styrene was 5.3% for the passive monitor for levels ranging from 1.2 to 104 ppm. Measurements of 235 personal exposures with the active monitor in 12 facilities manufacturing fiberglass-reinforced plastics (FRP) showed that levels of AP and PAA were below 7.8 ppb and 5 ppb, respectively. In contrast, SO averaged 30.4 ppb (SE=2.4) in these FRP facilities, ranging from below 0.2 ppb to 190 ppb. The active monitor was also used to detect airborne SO at levels of approximately equals 1 ppb in one facility manufacturing styrene butadiene rubber, suggesting that SO is generally present during the polymerization of styrene. Personal passive monitoring in the 12 FRP facilities (n = 657) revealed mean concentrations of styrene ranging between 1.8 and 55.4 ppm, and for SO between 1.7 and 62.6 ppb. The ratio of the mean styrene level to the mean SO level varied between 449:1 and 1,635:1 among the 12 FRP facilities.  相似文献   

18.
The aim of the study was to develop a sampling method aimed at individual sampling of mercury vapor and subsequent individualexposure assessment of the worker. Hopcalite available fromInowrocawskie Zakady Chemiczne (in Poland) was founduseful for mercury vapor sampling in active and passive individual samplers. However the sampling rate determined forpassive sampler in steady-state laboratory chamber cannot be usedunder fluctuating conditions of mercury vapor concentration andair movement typical for field measurement. In order to check comparativeness of passive and active sampling methods, sampleswere taken in the same time and individual samplers fixed toworker's clothes were used. Mercury vapor concentration wasmeasured at two chloralkali industries in Poland and the resultswere presented. Excessive exposure in both industries wasconfirmed by finding elevated mercury concentration in urinesamples from the workers.  相似文献   

19.
Aqueous triethanolamine (TEA) solutions are widely used as sorption medium for passive sampling of ambient NO2, with NO2 trapped and accumulated as nitrite ion. The results of test measurements of ambient NO2 concentrations using passive sampling method showed that the simple approach commonly used to describe passive sampling process might lead to substantial systematic errors. Presented in the article is a new physicochemical model of the process of passive sampling of gaseous NO2, with aqueous TEA solution used as a trapping medium. The model is based on the available results of experimental studies of interaction of gaseous NO2 with TEA/water solutions. The key principles underlying the model are: (1) when absorbed by a trapping solution, NO2 forms nitrite ion only on the condition that TEA is hydrated; (2) coefficient of conversion of NO2 to NO 2 ? is equal to one when reacting with hydrated TEA; and (3) the fraction of hydrated TEA molecules depends on air humidity at the moment of measurement. Validation of the model was made using the data of the field measurements carried out in the Middle Urals in 2007–2009. The new model was used to calculate average NO2 concentrations. Concentrations calculated agreed well with the results obtained by reference methods. The difference between the datasets was statistically insignificant.  相似文献   

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