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81.
The Radiello Passive Air Sampler is one of the latest innovations developed for the sampling of pollutants in the air by passive headspace. It has been reported that its properties allow an enhanced sensitivity, reproducibility and adsorption capacity. It therefore appears to be of interest in the extraction of potential residues of ignitable liquids present in fire debris when arson is suspected.A theoretical approach and several laboratory tests have made it possible to precisely characterize in a forensic perspective the potential of the device in extracting and concentrating the vapors of ignitable liquids found in fire debris. Despite some advantages, the Radiello device appears to be less efficient than traditional axial symmetry samplers. 相似文献
82.
In this paper we describe an environmentally friendly and sensitive method for the determination of ten primary amines in sewage sludge. The method is based on pressurised hot water extraction (PHWE) followed by simultaneous derivatization with pentafluorobenzaldehyde (PFBAY) and headspace solid-phase microextraction (HS-SPME) and subsequent gas-chromatography ion-trap tandem mass spectrometry (GC-IT-MS-MS) analysis. The influence of the main factors on the PHWE of sludge was optimized by a central composite design. For all species the optimal conditions were water at pH 4 as the extracting solvent, an extraction temperature of 100 °C and an extraction time of 15 min. The separation and detection of the ten amines by GC-IT-MS-MS took just 10 min and the entire process took approximately 1 h. Repeatability and reproducibility between days, expressed as RSD (%) (n = 5), were less than 19 and 24%, respectively. The average limit of detection (LOD) was of 65 μg kg−1 s (range found 9-135) and the average limit of quantification (LOQ) was of 230 μg kg−1 (range found 50-450) of dry weight (d.w.). Under optimized conditions we used this method to determine the compounds in industrial and municipal sewage sludge samples and in sludge from a potable water treatment plant. Methylamine and isobutylamine showed the highest levels in one of the industrial sewage sludge samples (404 and 543 mg kg−1 (d.w.), respectively). To our knowledge, this paper presents for the first time the determination of ten primary amines in sewage sludge samples using PHWE. 相似文献
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二级热脱附-气相色谱-质谱联用测定大气可吸入颗粒物中的16种多环芳烃 总被引:1,自引:0,他引:1
建立了二级热脱附-气相色谱-质谱联用技术测定大气可吸入颗粒物PM10中16种多环芳烃的分析方法。对二级热脱附和色谱-质谱条件进行了优化。实验结果表明,方法的检出限为0.14~0.42 ng/m3,平均加标回收率为52.7%~97.9%,相对标准偏差(RSD)为8.0%~18.4%。与传统方法相比,该方法的样品前处理时间短、有机溶剂的使用量少,是对人体及环境友善的检测技术。该方法已应用于32份实际大气颗粒物样品的分析。 相似文献
86.
顶空气相色谱-质谱法测定玩具中的10种挥发性有机物 总被引:1,自引:0,他引:1
建立了检测玩具中10种挥发性有机物(VOC)残留量的顶空气相色谱-质谱(HS-GC-MS)方法。样品经140 ℃、45 min静态顶空后,通过DB-624色谱柱分离和质谱检测,外标法定量。该方法对于不同VOC的定量限(LOQ)均在0.66 mg/kg以下,线性范围为0.001~2.0 μg,平均回收率在79%~106%之间,相对标准偏差(RSD)在0.4%~5.6%之间。该方法具有准确灵敏、简单快速等特点,将其应用于实际玩具样品的检测取得了良好效果。 相似文献
87.
固相萃取-离子色谱/气相色谱-质谱法联合检测油田水中的有机酸和酚类化合物 总被引:1,自引:0,他引:1
建立了固相萃取-离子色谱(IC)/气相色谱-质谱(GC-MS)联合检测高矿化度油田水中低相对分子质量的有机酸和酚类化合物的方法。在中性pH条件下,样品经Waters Oasis HLB柱萃取后,萃取液经稀释、Ag2O沉淀和Ag-H柱处理除去大部分氯离子,再用IC测定有机酸;将萃取柱真空冷冻干燥,然后经甲基叔丁基醚/甲醇(9:1, v/v)脱附并用无水硫酸钠除水,再用GC-MS检测酚类化合物。在优化的实验条件下,4种低相对分子质量的有机酸以及5种酚类化合物的平均加标回收率达到80%以上,相对标准偏差(RSD, n=6)为2.38%~9.45%,定量限均低于88.9 μg/L。该方法测定结果准确可靠,适用于氯离子含量高达150 g/L左右水样中低相对分子质量的有机酸和酚类化合物的检测。 相似文献
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利用气相色谱质谱(GC/MS)电子轰击方法,对6种不同年龄和不同性别的赤鳞鱼肉中的饱和、不饱和脂肪酸(经甲酯化后)进行了测定,用色谱法作了定量,共鉴定出18种脂肪酸。 相似文献
90.
C. Giachetti 《Chromatographia》1998,48(5-6):443-449
Summary Low amounts of triethanolamine, collected in ORBO 53 tubes during air sampling, required the development of a very sensitive
method for determination. After desorption and silylation reaction with trimethylsilyl imidazole/trimethyl chlorosilane, the
derivative was analyzed by gas chromatography-mass spectrometry on an Ultra 2 silica capillary column in single ion monitoring
mode (retention time: about 6 min). The method has a detection limit of 1–2 pg with a desorption efficiency of about 81%.
Linearity of response was ascertained in the ranges 10–100 ng and 100–1000 ng. Short-term method validation was carried out
by intra- and inter-day assays on three amounts for each reference calibration curve. All results satisfied the pre-defined
acceptance criteria. In general, the whole procedure was easily performed and was appropriate for our needs. Breakthrough
volume was appropriate for our needs. Breakthrough volume was determined on authentic samples and was about 40–60 L, using
a flow rate of 1 L·min−1. The amounts of triethanolamine found in the samples ranged from 150 to 250 ng (about 2.5–4.2 μg·m−3). 相似文献