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黄宏窦文渊郭杰煌陈飞龙农云军 《理化检验(化学分册)》2022,(7):841-847
通过对比填充不同吸附剂的不锈钢吸附管对10种醇类和醚类化合物的吸附能力,优化热脱附条件,考察不同色谱柱和样品保存时间对测定结果的影响,提出了热脱附-气相色谱-质谱法同时测定工作场所空气中10种醇类和醚类化合物含量的方法。用填装Tenax GR的吸附管采集气体样品,采集完成后将吸附管两端封好,设置一次热脱附温度为220℃,二次热脱附温度为240℃,吹扫时间为4 min,进样时间为50 s,在上述条件下进行热脱附,脱附的气体进入气相色谱仪,采用DB-624毛细管色谱柱分离目标物,并用配电子轰击离子源的质谱仪在选择离子监测模式下检测。结果显示:10种醇类和醚类化合物的质量在10~300 ng内与其对应的峰面积呈线性关系,检出限(3.143s)为0.5~1.9 ng;对空白样品进行3个浓度水平的加标回收试验,回收率为70.5%~125%,测定值的相对标准偏差(n=6)为1.0%~20%;方法用于实际样品分析,正丁醇、异丁醇和仲丁醇被检出,检出量依次为0.013,0.007,0.008 mg·m^(-3)。 相似文献
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粮谷和油籽中丰索磷残留量的气相色谱及气相色谱/质谱分析 总被引:3,自引:0,他引:3
介绍应用气相色谱和气相色谱-质谱法测定及确证粮谷和油籽中丰索磷的残留含量,试样采用水-丙酮提取,提取液经液-液分配后,再以弗罗里硅土柱净化,气相色谱,火焰光度检测器测定,外标法定量,并用气相色谱-质谱针对丰索磷的选择监测离子的种类和丰度比进行敢阳性确证。 相似文献
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作者改进了气提法富集水中痕量挥发性有机物装置。研究了实验条件对水中痕量有机物富集的影响,并确定了最佳富集条件。以气提法富集气相色谱/质谱法(GC/MS)测定了水样中痕量挥发性有机物,取得了满意的结果。 相似文献
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离线超临界流体萃取和气相色谱/质谱联用对实验室内空气中气相有机?… 总被引:7,自引:0,他引:7
通过固体吸附富集,再用超临界CO2脱附后用气相色谱及质谱技术对实验室内空气中气相有机污染物进行了考察,文中对采样和萃取条件进行了优化,并与热脱附所得结果做了比较,结果表明在22MPa,80℃时,用甲醇改性的超临界CO2进行萃取的结果优于热脱附法,该法鉴定出气相有机污染物中52个组分,占色谱峰总面积的99.6%。 相似文献
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Suwannee Junyapoon Keith D. Bartle Andrew B. Ross Michael Cooke Brian F. Smethurst 《International journal of environmental analytical chemistry》2013,93(4):337-348
Abstract Trace volatile compounds emitted from both domestic and industrial landfills have been identified by programmed temperature vaporization injection (PTV) coupled to gas chromatography with detection by ion-trap mass spectrometry (GC-ITD/MS). The PTV injection system has been developed using a combination of two six-port valves to achieve problems of interference in GC-MS while loading sample. A large volume of landfill gas was re-concentrated onto a sorbent trap, then rapidly liberated into the GC-ITD/MS system by programmed thermal desorption. Using this method, trace volatile compounds in gases from both domestic and industrial landfills such as aromatic hydrocarbons, terpenes, chlorinated hydrocarbons, and sulfur compounds can be identified and quantified. 相似文献
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Highly porous polyaniline/hexagonally ordered silica sorbent was used for fabrication of the inside needle capillary adsorption trap (INCAT) device. Polyaniline/SBA-15 nanocomposite was synthesized via chemical polymerization technique. The fabricated INCAT device was evaluated to the extraction of some polycyclic aromatic hydrocarbons (PAHs) from aqueous sample solutions in combination with gas chromatography (GC)-mass spectrometry (MS). A one at-the-time optimization strategy was applied for optimizing the important extraction parameters such as extraction temperature, extraction time, ionic strength, sampling flow rate, desorption time, and desorption temperature. In optimum conditions (extraction temperature 55 °C, extraction time 20 min, ionic strength 20% (w/v), flow rate 4.5 mL min(-1), desorption temperature 270 °C, desorption time 3 min) the repeatability for one INCAT device (n = 4), expressed as relative standard deviation, was between 4.2 and 10.2% for the tested compounds. The quantitation limits for the studied compounds were between 1 and 5 pg mL(-1). The developed method was successfully applied to spring water sample which was spiked with PAHs with the relative recovery percentages of 87.3-109.1%. The developed method offers the advantage of being simple to use, with shorter analysis times, lower cost of equipment, and thermal stability. 相似文献
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Julien Parinet Jean Serodes François Proulx 《International journal of environmental analytical chemistry》2013,93(6):505-515
This paper describes a method of determining the following compounds in water characterised by complex matrices (raw waters and drinking waters): geosmin, 2-methylisoborneol (2-MIB), 2-isobutyl-3-methoxypyrazine (IBM), 2-isopropyl-3-methoxypyrazine (IPM) and 2,4,6-trichloroanisole (TCA). The method is carried out using headspace solid-phase microextraction (HS-SPME) combined with gas chromatography (GC) and ion trap mass spectrometry (ITMS). Several parameters of extraction and desorption were optimised through the use of a Combi PAL autosampler to automate various tasks (temperature extraction, extraction time, stir speed). Quantities of NaCl and the liquid volume/total volume ratio were also optimised. Double fragmentation (tandem MS/MS) was optimised on the target compounds. The method resulted in good linearity obtained for concentrations of 1 to 100?ng?L?1 and provided detection limits of approximately below 1?ng?L?1. Good precision (1–8%) was obtained. This method was successfully applied to the analysis of earthy and musty odours in municipal raw source waters with high concentrations of natural organic matter and in the corresponding treated waters. This is the first time MS/MS has been used to analyse odorous compounds in waters destined for human consumption. In addition, the method as developed is simple to use and lends itself to easy interpretation of chromatograms. 相似文献
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R. A. Moore F. W. Karasek 《International journal of environmental analytical chemistry》2013,93(3-4):203-221
Abstract Water samples from the Caroni River, Trinidad and other rivers which flow into the Caroni River were qualitatively analyzed for trace organic contaminants by procedures based on XAD extraction followed by GC/MS analysis. Pesticides, polyaromatic hydrocarbons, aliphatic hydrocarbons, phenols and phthalate esters were the main groups of compounds found. Many of the contaminants present in these water samples are known industrial pollutants, and several have been found in waste waters examined by other workers, which suggests that the factories of an industrial complex located upstream of the Caroni/Arena Water Treatment Plant may be the major source of the pollutants. Some compounds identified in the water samples have not been previously reported. 相似文献
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吹扫/捕集-热脱附气质联用法对荷叶挥发油成分的对比分析 总被引:3,自引:0,他引:3
采用同时蒸馏萃取提取得到荷叶挥发油, 通过吹扫/捕集-热脱附法(P&T-TD)对上述提取物中挥发性成分进行富集, 以气质联用(GC/MS)进行定性检测, 同时与直接进样GC/MS法分析的成分进行比较. 两种方法成功分离分析出有机酸、酯、醛、醇、酚、烷烃、芳香烃、烯烃以及含氮、硫、氧杂原子的化合物等共计84种成分, 其中P&T-TD GC/MS鉴定出63种有机化合物, GC/MS鉴定出41种有机化合物, 有20种成分共同检出. 对比分析表明: P&T-TD GC/MS的吹扫/捕集-热脱附过程能富集各种组分, 相比GC/MS分析, 可以鉴定出微量成分及更多挥发性和半挥发性成分, 在精油等挥发性成分的分析检测中使用优势明显. 相似文献
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The development of a method for screening of organic compounds with a wide range of physico-chemical properties in water, based on dual stir bar sorptive extraction coupled with thermal desorption and gas chromatography–mass spectrometry (dual SBSE-TD-GC–MS) is described. The investigated water sample is divided into two aliquots and extracted with stir bar sorptive extraction at two different conditions: using addition of methanol or sodium chloride, respectively. Following extraction, the two stir bars are inserted into the same glass thermal desorption liner and are simultaneously desorbed and analysed by GC–MS. The method optimisation was performed using 45 environmentally harmful substances with different volatilities (boiling point from 193 to 495 °C), polarity (log Kow from 2.17 to 8.54) and acido-basic properties. The majority of model compounds was selected from the EU list of priority substances in the field of water policy and from the US EPA method 625, respectively. Optimisation was performed for extraction parameters (sample volume, extraction time, stirring rate, addition of modifiers) as well as for the thermal desorption conditions (desorption flow, desorption time, cryofocusing temperature). Performance characteristics (recovery, repeatability, carryover, linearity, limits of detection and quantification) were determined for the optimised method. An example of analysis of a contaminated groundwater sample is presented. 相似文献
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Ming-Chi Wei 《Talanta》2007,72(4):1269-1274
The novel pretreatment technique, microwave-assisted heating coupled to headspace solid-phase microextraction (MA-HS-SPME) has been studied for one-step in situ sample preparation for polycyclic aromatic hydrocarbons (PAHs) in aqueous samples before gas chromatography/flame ionization detection (GC/FID). The PAHs evaporated into headspace with the water by microwave irradiation, and absorbed directly on a SPME fiber in the headspace. After being desorbed from the SPME fiber in the GC injection port, PAHs were analyzed by GC/FID. Parameters affecting extraction efficiency, such as SPME fiber coating, adsorption temperature, microwave power and irradiation time, and desorption conditions were investigated.Experimental results indicated that extraction of 20 mL aqueous sample containing PAHs at optional pH, by microwave irradiation with effective power 145 W for 30 min (the same as the extraction time), and collection with a 65 μm PDMS/DVB fiber at 20 °C circular cooling water to control sampling temperature, resulted in the best extraction efficiency. Optimum desorption of PAHs from the SPME fiber in the GC hot injection port was achieved at 290 °C for 5 min. The method was developed using spiked water sample such as field water with a range of 0.1-200 μg/L PAHs. Detection limits varied from 0.03 to 1.0 μg/L for different PAHs based on S/N = 3 and the relative standard deviations for repeatability were <13%. A real sample was collected from the scrubber water of an incineration system. PAHs of two to three rings were measured with concentrations varied from 0.35 to 7.53 μg/L. Recovery was more than 88% and R.S.D. was less than 17%. The proposed method is a simple, rapid, and organic solvent-free procedure for determination of PAHs in wastewater. 相似文献
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A simple solid-phase microextraction (SPME) device, coupled with gas chromatography-electron capture detection (GC-ECD) was developed to detect trace levels of chloro- and nitrobenzene compounds in environmental water samples. Polyaniline (PANI) was chosen as the extraction material for the SPME device, and was electrochemically deposited on a stainless steel wire to achieve high mechanical stability. Due to the peculiar pi-pi conjugated structure, PANI coating shows a stable performance in high temperature (to 350 degrees C) and solvents (organic and inorganic). The porous structure of PANI film characterized by scanning electron microscopy (SEM) revealed high extraction efficiency. The possible extraction mechanism was explained by the study carried out using electrochemical impedance spectroscopy (EIS). Eight chloro- and nitrobenzene compounds were selected to evaluate the SPME-GC procedures. The key parameters such as extraction and desorption temperature and time, and the ionic strength were investigated and optimized. The method was applied to the detection of environmental water samples collected from Taihu Lake, representing nowadays contamination level under industrial impact. The whole PANI-SPME-GC method offers high accuracy and precision, high sensitivity and low detection limits. Thus, the method developed could be used as a new way to monitor the trace levels of chloro- and nitrobenzene compounds in real water bodies. 相似文献
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建立了工业苯酚中有机杂质的固相微萃取-气相色谱(SPME-GC)分析方法。实验考察了SPME萃取温度和萃取时间的影响,同时也优化了热解吸时间。优化后的萃取温度为20 ℃,萃取时间为10 min,热解吸时间为30 s。使用此法对工业苯酚样品中的两种主要有机杂质进行了分析检测,结果表明: 2-甲基苯并呋喃和2,4-二苯基-4-甲基-1-戊烯分别在0.05~1.06 mg/L和0.05~0.99 mg/L范围内线性关系良好(r2分别为0.990和0.992),检出限分别为0.5和1.6 μg/L。在0.1 mg/L的添加水平下,2-甲基苯并呋喃和2,4-二苯基-4-甲基-1-戊烯的回收率分别为104%和113%。该方法具有简单、快速、灵敏度高等优点,适合于工业苯酚中这两种主要痕量有机杂质的准确定量分析。 相似文献