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报道了调味品中氯丙醇的衍生化气相色谱(GC/ECD)和衍生化气相色谱双串联质谱法(GC/MS/MS)测定。GC/ECD测定酱油中3—氯—1,2—丙二醇(3—MCPD)的检出限达到0.01mg/kg,回收率为91%~104%,变异系数为2.27%~7.96%;GC/MS/MS同时测定酱油中1,3—二氯—2—丙醇、2,3—二氯—1—丙醇和3—氯—1,2—丙二醇,1,3—二氯—2—丙醇、2,3—二氯—1—丙醇的检出限为0.02mg/kg,3—氯—1,2—丙二醇的检出限为0.01mg/kg,回收率在92%~106%,变异系数为3.51%~13.33%。  相似文献   

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乙酰乙酸乙酯烯醇式与酮式GC/MS和GC/IR分析   总被引:1,自引:0,他引:1  
采用GC/MS对乙酸乙酯烯醇式在不同离子源温度,接口温度,进样器温度,柱温等条件下的气相色谱行为进行了研究,用重氢交换法和高分辨质谱法对烯醇式和酮式的质谱进行了解析,并通过GC/IR研究了烯醇式和酮式的红外光谱。  相似文献   

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The chemical characterisation of waterlogged archaeological wood is of paramount importance in terms of understanding not only the degradation processes of wood in artistic and archaeological objects but also the development of consolidation and conservation procedures. The two different types of archaeological waterlogged wood were characterized using several analytical techniques. The analytical protocol consists in using PY/GC/MS with in situ derivatisation with hexamethyldisilazane, GC/MS of the extractives, 1H, 13C and 31P NMR analysis, and GPC. The main results showed that one of the ancient samples was a gymnosperm wood from the Pinaceae family, whereas the other type of wood was an angiosperm. Lignin from the angiosperm was oxidised in a benzylic position of β-O-4 to give oxo functional groups, in primary alcohol moiety to give carboxylic groups. In addition, the formation of a new intermonomeric bond 5-O-4 was observed.  相似文献   

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This paper describes a design for an all-glass GC/MS interface. The design has advantages due to low dead volume, lack of column effluent adsorption and degradation, simple interface production and installation, and ease of column mounting/dismounting.  相似文献   

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Modification of commercial LC/MS instrumentation to allow both atmospheric pressure (AP) LC/MS and GC/MS is described. Advantages of this additional capability versus LC/MS alone include higher chromatographic resolution in the GC versus LC mode, greater peak capacity for complex mixture analysis, higher sensitivity for a variety of volatile compounds, and the ability to observe compounds of low polarity that are not readily observed in LC/MS. Advantages over conventional GC/MS include the ability to use higher carrier gas flow and shorter columns for passing less volatile materials through the gas chromatograph, selective ionization, and rapid switching between positive and negative ion modes. Other advantages include application of the enhanced capabilities of LC/MS instrumentation to GC/MS analyses such as cone voltage fragmentation, MS(n), high mass resolution, and accurate mass measurement. Limitations of APGC/MS include the inability to observe saturated hydrocarbon and certain other highly nonpolar compounds and less odd-electron fragmentation for computer aided library searching. For some analyses, the limitation related to ionization of highly nonpolar compounds is advantageous, as is the simplified mass spectrum and easy molecular weight identification that results from less fragmentation observed in the AP ionization mode.  相似文献   

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The use of mass chromatogram peak centroids has been investigated as a means of deconvoluting the spectra of overlapping gas chromatography/mass spectrometry components. The peak centroids have been calculated with a precision of 0.04 scans (sd). This proved sufficient to allow deconvolution of the mass spectra belonging to two chemical components which were eluted 0.48 scans apart. For a more complex chromatography peak, it was possible to deconvolute the spectra of six components which were eluted within a 9 scan window. All the spectra produced by using this deconvolution mechanism agreed well with National Institute of Standards and Technology database spectra.  相似文献   

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The determination of Dinocap, one of the most often used acaricides and contact fungicides, is complicated by the fact that it consists of several isomeric alkyldinitro-phenyl-crotonates. In a first step, GC/IR and GC/MS has been used to separate the mixture, to determine the chromatographic behaviour and to fully characterize the six different isomeric compounds. The structures of additional impurities in the commerical preparation were shown to be the correlating phenols. An extraction/preconcentration method has been devised based on Carbopack B, yielding recoveries between 75 and 98%. A qualified estimation of the total Dinocap content of drinking water can be made by this approach for concentrations well below the limits set by the European drinking water regulations. The development of a complete analytical procedure based on these results appears to be feasible.Dedicated to Professor Dr. Dr. h.c. mult J. F. K. Huber on the occasion of his 70th birthday  相似文献   

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刘布鸣  苏小川 《色谱》2006,24(2):211-211
多廿醇是从制糖滤泥中分离得到的一种高级脂肪伯醇天然混合物,其化学组成分析未见报道。本文采用气相色谱法(GC)和气相色谱/质谱法(GC/MS),对其组分和结构进行了分析和鉴定。  相似文献   

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Ion mobility spectrometry (IMS) is a well-known analytical method for the detection of CWAs and explosives since many years. Coupling IMS to GC pre-separation, new application fields in medicine and biology could be opened, dealing with complex and humid mixtures. However, identification of unknowns in such a complex sample is challenging and can only be achieved by parallel GC/MS analysis, thus obtaining a proposal for the responsible compound for validation via reference substances by GC/IMS again. The available adsorption tools for such accompanying GC/MS analysis have their particular drawbacks (e.g. problematic quantification for SPME, high sample volumes for adsorption tubes). Therefore miniaturised adsorption needles (NeedleTrap) were applied to both GC/IMS and GC/MS for validation of their reproducibility. It could be demonstrated that the needles can even be used for appropriate quantification when the adsorbent and the sample volume are adapted properly to the concentration range, the compounds of interest and humidity of the sample. The method is very flexible with regard to the concentration range by variation of the sample volume (e.g. 20 mL for pptV, 10 mL for lower ppbV or 1 mL for ppmV) and with regard to the compounds of interest by application of common adsorption materials optimised for the relevant substance group. Such materials are available commercially in a broad variability. Therefore, the miniaturised adsorption needles are a helpful complementary sampling method for any GC/MS or GC/IMS investigations.  相似文献   

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Summary 100 mg amounts of glue on two copper-age arrowheads have been investigated by means of gas-chromatography/mass spectrometry and chemometrics. The samples have been identified as birch bark derivatives, but the distribution patterns of triterpenoids and steroids show significant differences to similar samples from younger archaeological periods that can be explained by the use of a different species of birch and a different method of preparation.  相似文献   

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A simple and sensitive gas chromatography/tandem mass spectrometry (GC/MS/MS) method is described for the detection of anabolic steroids, usually found in keratin matrix at very low concentrations. Hair samples from seven athletes who spontaneously reported their abuse of anabolic steroids, and in a single case cocaine, were analyzed for methyltestosterone, nandrolone, boldenone, fluoxymesterolone, cocaine and its metabolite benzoylecgonine. Anabolic steroids were determinate by digestion of hair samples in 1 m NaOH for 15 min at 95 degrees C. After cooling, samples were purificated by solid-phase and liquid-liquid extraction, then anabolic steroids were converted to their trimethylsilyl derivative and finally analyzed by GC/MS/MS. For detection of cocaine and benzoylecgonine, hair samples were extracted with methanol in an ultrasonic bath for 2 h at 56 degrees C then overnight in a thermostatic bath at the same temperature. After the incubation, methanol was evaporated to dryness, and benzoylecgonine was converted to its trimethylsilyl derivative prior of GC/MS/MS analysis. Results obtained are in agreement with the athletes' reports, confirming that hair is a valid biological matrix to establish long-term intake of drugs.  相似文献   

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Pharmaceuticals have become major targets in environmental chemistry due to their presence in aquatic environments (following incomplete removal in wastewater treatment or point-source contaminations), threat to drinking water sources and concern about their possible effects to wildlife and humans. Recently several methods have been developed for the determination of drugs and their metabolites in the lower nanogram per litre range, most of them using solid-phase extraction (SPE) or solid-phase microextraction (SPME), derivatisation and finally gas chromatography mass spectrometry (GC-MS), gas chromatography tandem mass spectrometry (GC-MS/MS) and liquid chromatography electrospray tandem mass spectrometry (LC-ES/MS/MS). Due to the elevated polarity of non-steroidal anti-inflamatory drugs (NSAIDs), analytical techniques based on either liquid chromatography coupled to mass spectrometry (LC-MS) and gas chromatography coupled to mass spectrometry (GC-MS) after a previous derivatisation step are essential. The most advanced aspects of current GC-MS, GC-MS/MS and LC-MS/MS methodologies for NSAID analysis are presented.  相似文献   

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Arsenic-containing hydrocarbons have recently been reported as natural constituents of fish oil. We report a simple method for determining these compounds by GC/MS. Application of the methodology will delineate the distribution of these novel arsenic compounds in foods, and facilitate an assessment of the toxicological implications.  相似文献   

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