共查询到20条相似文献,搜索用时 203 毫秒
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本文以聚乙烯(PE)塑料制品——保鲜膜和聚乙烯原料为研究对象,探究二者对纵火现场助燃剂柴油分析鉴定的影响。利用固相微萃取–气相色谱–质谱法(SPME-GC-MS)对本体、未完全燃烧、完全燃烧至自燃熄灭三种不同燃烧状态下的样品与柴油的特征谱图进行对比分析。通过聚乙烯原料和PE保鲜膜本体进行对比分析发现,二者所含主要成分基本相同,PE保鲜膜中含有的个别组分在聚乙烯原料中并未检测到,主要是由于PE保鲜膜在生产过程中加入了一些添加剂所致。未完全燃烧保鲜膜对柴油分析影响最大,当m/z=85、178、192、183时,二者含有相同的成分且分布规律也基本相同,但当提取离子m/z=83时,未完全燃烧保鲜膜样品中不含有与柴油相同的环烷烃。应用SPME-GC-MS技术可以将未完全燃烧保鲜膜与柴油区分开,该方法灵敏度高,分析速度快,适用于火场中助燃剂的分析。 相似文献
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固相微萃取-气相色谱质谱法测定血浆中的氯氮平浓度 总被引:1,自引:0,他引:1
目的建立固相微萃取-气相色谱质谱法测定人血浆中氯氮平浓度的方法。方法以固相微萃取法提取血浆中的氯氮平,萃取头为100μm聚二甲基硅氧烷,洛沙平作内标,用气相色谱质谱选择离子法进行检测。结果本文建立的方法在5~2000 ng/ml浓度范围内呈线性关系,检测限为0.1 ng/ml(信噪比>3),低、中、高浓度(100、500、1000 ng/ml)平均相对回收率分别为98.6%、94.6%和94.6%,日内、日间RSD分别小于7.4%和7.1%。结论本文建立的固相微萃取-气相色谱质谱法灵敏度高、准确度好、操作简便,适用于氯氮平急性中毒案件的检测。 相似文献
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Kah Haw Chang B.Sc. Chong Hooi Yew Ph.D. Ahmad Fahmi Lim Abdullah Ph.D. 《Journal of forensic sciences》2014,59(4):1100-1108
Smokeless powders are low explosives and are potentially found in cases involving firearms and improvised explosive devices. Apart from inorganic compound analysis, forensic determination of organic components of these materials appears as a promising alternative, especially the chromatographic techniques. This work describes the optimization of a solid‐phase microextraction technique using an 85 μm polyacrylate fiber followed by gas chromatography‐flame ionization detection for smokeless powder. A multivariate experimental design was performed to optimize extraction‐influencing parameters. A 24 factorial first‐order design revealed that sample temperature and extraction time were the major influencing parameters. Doehlert matrix design has subsequently selected 66°C and 21 min as the compromised conditions for the two predetermined parameters. This extraction technique has successfully detected the headspace compounds of smokeless powders from different ammunition types and allowed for their differentiation. The novel technique allows more rapid sample preparation for chromatographic detection of smokeless powders. 相似文献
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A method is described for the gas chromatographic quantitation of carbon monoxide by means of thermal conductivity detection. Carbon monoxide is released from blood samples as small as 0.02 mL using a unique extraction chamber. The method was compared to a standard gas chromatographic and spectrophotometric method of carbon monoxide quantitation. It was comparable to the former with all samples evaluated and apparently more reliable than the latter with decomposed samples. 相似文献
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目的建立血样中4种常见巴比妥类药物的固相萃取方法。方法采用Oasis MAX固相萃取柱对样品进行预处理,以2%氨水淋洗2,%甲酸-甲醇洗脱,GC/NPD定量检验,GC/MS定性检验。结果血样中4种常见巴比妥类药物平均萃取回收率达80%以上,以信噪比10/1计,最小定量限为1~2μg/mL,以信噪比3/1计,检出限为0.5~1μg/mL,在1~50μg/mL范围内,线性相关系数均在0.99以上。结论本文固相萃取方法检出限低,回收率高,选择性强,可应用于血样中4种常见巴比妥类药物的检测。 相似文献
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Nylon bags containing 2-g portions of Amberlite XAD-2 resin were used for systematic analysis of drugs in biosamples. The procedure requires 10 or less grams of material, two XAD-2 bags, and enables rapid and economical isolation of most common drugs. The method was demonstrated on autopsy blood spiked with 19 of the most common drugs, and was routinely used in cases of fatal and non-fatal poisoning. The eluates were clean and suitable for direct gas chromatographic and ultraviolet spectrophotometric analysis.The procedure used appeared more convenient than XAD-2 column extraction procedures. Classic solvent extraction methods were usually less efficient. 相似文献
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Andersson K Jalava K Lock E Huizer H Kaa E Lopes A Poortman-van der Meer A Cole MD Dahlén J Sippola E 《Forensic science international》2007,169(1):64-76
The suitability of liquid-liquid extraction (LLE) and solid-phase extraction (SPE) for the preparation of impurity extracts intended for gas chromatographic profiling analyses of amphetamine were evaluated. Both techniques were optimised with respect to the extraction of selected target compounds by use of full factorial designs in which the variables affecting the performance were evaluated. Test samples consisted of amphetamine synthesised by the Leuckart reaction, by reductive amination of benzyl methyl ketone and by the nitrostyrene route. The performance of LLE and SPE were comparable in terms of repeatability and recovery of the target compounds. LLE was considered the better choice for the present harmonised amphetamine profiling method due to the lack of information on the long-term stability of SPE columns. 相似文献
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An improved technique for cocaine extraction from urine samples for gas chromatographic (GC) analysis is described. Employing a simple liquid-liquid extraction (LLE) of cocaine with a mixture of ethyl ether:isopropanol (9:1) the method presents a mean recovery of 74.49%. Limit of detection (LOD) and limit of quantification (LOQ) were 5 and 20 ng/ml, respectively. The method is highly precise (coefficient of variation (CV) <8%) and linear from 20 to 2000 ng/ml. It can he applied to detect the presence of cocaine in urine as a marker of its recent use in drug abuse treatment protocols. 相似文献