Bibliografie tematiche / Gaz chromatography Masss Spectrometry (GC-MS)

Letteratura scientifica selezionata sul tema "Gaz chromatography Masss Spectrometry (GC-MS)"

Autore: Grafiati

Pubblicato: 8 giugno 2024

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Articoli di riviste sul tema "Gaz chromatography Masss Spectrometry (GC-MS)":

Ababutain, Ibtisam. "Antimicrobial Activity and Gas Chromatography-Mass Spectrometry (GC-MS) Analysis of Saudi Arabian Ocimum basilicum Leaves Extracts". Journal of Pure and Applied Microbiology 13, n. 2 (30 giugno 2019): 823–33. http://dx.doi.org/10.22207/jpam.13.2.17.

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IWASA, Shuichi, Shigeki OHIGASHI, Toshio KOSAKI, Yukiko SHIMIZU, Kazunori KOMATSUZAKI, Masafumi HASHINO, Hiroshi SAITO e Takumi YANAIHARA. "19-Hydroxyandrostenedione in Human Ovarian Vein Measured by GC-MS". Folia Endocrinologica Japonica 67, n. 6 (1991): 692–701. http://dx.doi.org/10.1507/endocrine1927.67.6_692.

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Jordáková, I., J. Dobiáš, M. Voldich e J. Poustka. "Determination of vinyl chloride monomer in food contact materials by solid phase microextraction coupled with gas chromatography/mass spectrometry". Czech Journal of Food Sciences 21, No. 1 (18 novembre 2011): 13–17. http://dx.doi.org/10.17221/3472-cjfs.

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The present study concerns the optimisation of the headspace solid phase microextraction (HS/SPME) combined with gas chromatography/mass spectrometry (GC/MS) for the vinyl chloride monomer determination. Samples of PVC materials were analysed using the Carboxen/Polydimethylsiloxane (CX/PDMS) 75 µm fibre. For this fibre, the achieved limit of detection was 0.05 µg/kg, and that of quantification 0.17 µg/kg, respectively, with RSD 5%. The levels of VCM found ranged from 0.29 to 0.44 mg/kg, in the case of foil, the VCM content determined was 3.65 mg/kg which means that the maximal limit allowed was exceeded.  

Aisiyah, Adella, Ajeng Nita Aryani, Diva Rizqi Salsabilla, Putri Mutiara Iskandar e Silvana Lestari Irwansyah. "Identifikasi Senyawa Mdma dan Paracetamol dalam Sampel Urine Menggunakan Metode Kromatografi Lapis Tipis dan Kromatografi Gas – Spektrofotometri Massa (Gc-Ms)". Jurnal Health Sains 3, n. 5 (24 maggio 2022): 690–96. http://dx.doi.org/10.46799/jhs.v3i5.482.

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MDMA (3,4-methylenedioximet amphetamine) is a semisynthetic compound derived from stimulant type amphetamine (ATS) which works by triggering the release of serotonin. Paracetamol (acetaminophen) is one type of drug that has an analgesic-antipyretic effect. MDMA analysis requires a relatively fast method, so the TLC method was chosen. The identification test was carried out using 3 chromatographic systems, namely methanol: ammonia TA (100:1.5 v/v), methanol: butanol TAF (60:40 v/v), and Toluene: acetone: ethanol: ammonia TAEA (45: 45: 7: 3v/v/v/v). The determination test was carried out using the TAEA system and MDMA was used as a standard. The results of the identification test showed that the sample contained MDMA through the Hrfc and spectrum approaches. Qualitative Analysis of Paracetamol Compounds (Acetaminophen) in Urine aims to analyze paracetamol compounds (acetaminophen) in urine qualitatively by using gas chromatography - mass spectrometry (GC-MS). Extraction of paracetamol in urine samples was carried out using ethyl acetate, which was then derivatized using BSTFA containing 1% TMCS and analyzed using gas chromatography – mass spectrometry (GC-MS). The results showed that urine samples at 1, 2, and 3 hours after consuming paracetamol gave positive results for acetaminophen-TMS while at 24, 168, and 720 hours after consumption they were negative.

Timkovsky, J., A. W. H. Chan, T. Dorst, A. H. Goldstein, B. Oyama e R. Holzinger. "Organic aerosol composition measurements with advanced offline and in-situ techniques during the CalNex campaign". Atmospheric Measurement Techniques Discussions 7, n. 12 (12 dicembre 2014): 12449–80. http://dx.doi.org/10.5194/amtd-7-12449-2014.

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Abstract. Our understanding of formation processes, physical properties and climate/health effects of organic aerosols is still limited in part due to limited knowledge of organic aerosol composition. We present speciated measurements of organic aerosol composition by two methods: in-situ thermal-desorption proton-transfer-reaction mass spectrometry (TD-PTR-MS) and offline two-dimensional gas chromatography with a time-of-flight mass spectrometer (GC×GC/TOF-MS). 153 compounds were identified using the GC×GC/TOF-MS, 123 of which were matched with 64 ions observed by the TD-PTR-MS. A reasonable overall correlation of 0.67 (r2) was found between the total matched TD-PTR-MS signal (sum of 64 ions) and the total matched GC×GC/TOF-MS signal (sum of 123 compounds). A reasonable quantitative agreement between the two methods was observed for most individual compounds with concentrations which were detected at levels above 2 ng m−3 using the GC×GC/TOF-MS. The analysis of monocarboxylic acids standards with TD-PTR-MS showed that alkanoic acids with molecular masses below 290 amu are detected well (recovery fractions above 60%). However, the concentrations of these acids were consistently higher on quartz filters (quantified offline by GC×GC/TOF-MS) than those suggested by in-situ TD-PTR-MS measurements, which is consistent with the semivolatile nature of the acids and corresponding positive filter sampling artifacts.

Timkovsky, J., A. W. H. Chan, T. Dorst, A. H. Goldstein, B. Oyama e R. Holzinger. "Comparison of advanced offline and in situ techniques of organic aerosol composition measurement during the CalNex campaign". Atmospheric Measurement Techniques 8, n. 12 (10 dicembre 2015): 5177–87. http://dx.doi.org/10.5194/amt-8-5177-2015.

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Abstract. Our understanding of formation processes, physical properties, and climate/health effects of organic aerosols is still limited in part due to limited knowledge of organic aerosol composition. We present speciated measurements of organic aerosol composition by two methods: in situ thermal-desorption proton-transfer-reaction mass spectrometry (TD-PTR-MS) and offline two-dimensional gas chromatography with a time-of-flight mass spectrometer (GC × GC/TOF-MS). Using the GC × GC/TOF-MS 153 compounds were identified, 123 of which were matched with 64 ions observed by the TD-PTR-MS. A reasonable overall correlation of 0.67 (r2) was found between the total matched TD-PTR-MS signal (sum of 64 ions) and the total matched GC × GC/TOF-MS signal (sum of 123 compounds) for the Los Angeles area. A reasonable quantitative agreement between the two methods was observed for most individual compounds with concentrations which were detected at levels above 2 ng m−3 using the GC × GC/TOF-MS. The analysis of monocarboxylic acids standards with TD-PTR-MS showed that alkanoic acids with molecular masses below 290 amu are detected well (recovery fractions above 60 %). However, the concentrations of these acids were consistently higher on quartz filters (quantified offline by GC × GC/TOF-MS) than those suggested by in situ TD-PTR-MS measurements, which is consistent with the semivolatile nature of the acids and corresponding positive filter sampling artifacts.

Salah, Eldeen A. Ali. "Assessment of Cucumber and Paper Contamination by Pesticides Residues in Khartoum State using Quechers Method and Gas Liquid Chromatography-Mass Spectrometry". Food Science & Nutrition Technology 5, n. 3 (12 maggio 2020): 1–6. http://dx.doi.org/10.23880/fsnt-16000220.

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In this paper, we present the investigation of 30 pesticides in total of 138 samples of different fresh cucumber and paper from central markets in Khartoum state using the quick easy cheap effective rugged and safe (QuEChERS) multi-residue extraction, followed by gas chromatography-mass spectrometry (GC-MS). Pesticide residues were not detected in 68 samples (49.3%), while 70 samples (50.7%) contained detectable amount of pesticide residues. The percentages of contaminated vegetable samples are 69.4%, 47.2%, 38.9% and 30% for cucumber, sweet paper, green paper and armenian cucumber respectively. Multiple pesticides residues were detected on 6 samples with percentage of (4.3%) from total analyzed samples. Multiple residues with two pesticides were present in 2 and 4 samples of cucumber and sweet paper. Seven pesticides diazinon, cypermethrin, lamdacyhalothrin, dimethoate, pendimethalin, malathion and tetramethrin were detected in the analyzed vegetable samples with concentration range between 0.013-0.652 mg/kg and mean range between 0.0222-0.1927mg/kg of contaminated samples. It is necessary continuous monitoring of pesticide use on vegetables. Summer season was the highly contaminated with pesticides.

Kim, Jin Hyo, Jong Min Park, Geun-Hyoung Choi, Yun-Ki Park, Geon-Jae Im, Doo-Ho Kim e Oh-Kyung Kwon. "Comparison of Liquid Chromatography-Mass/Mass Spectrometry (MS) and Gas Chromatography-MS for Quantitative Analysis of Indole-3-acetic acid and Indole-3-butyric acid from the Concentrated Liquid Fertilizer". Journal of Applied Biological Chemistry 56, n. 1 (31 marzo 2013): 53–57. http://dx.doi.org/10.3839/jabc.2013.010.

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Delgado-Chavero, C. L., E. Zapata-Márquez, J. M. García-Casco e A. Paredes-Torronteras. "Statistical model for classifying the feeding systems of Iberian pigs through Gas Chromatography (GC-FID) and Isotope Ratio Mass Spectrometry (GC-C-IRMS)". Grasas y Aceites 64, n. 2 (10 aprile 2013): 157–65. http://dx.doi.org/10.3989/gya.130412.

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Fay, Laurent B., e Andreas A. Staempfli. "New Approach to Processing of Gas Chromatographic/Mass Spectrometric Data for Detection of Off Flavors in Complex Mixtures". Journal of AOAC INTERNATIONAL 78, n. 6 (1 novembre 1995): 1429–34. http://dx.doi.org/10.1093/jaoac/78.6.1429.

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Abstract Chemical compounds responsible for off flavors in foodstuffs are often difficult to identify because of their low levels in complex matrixes. A simple method is described to detect and identify off flavor compounds by gas chromatographic/mass spectrometric (GC/MS) analysis and data processing for sorting the GC/MS files in 14-ion series. The 14 homologous-ion series correspond to the sum of the intensities of the ions, x + (CH2)n, where x varies from 1 to 14 and n varies from 1 to ∞, allowing to cover the whole acquired mass range. Processing of the ion series allows automatic screening of all acquired masses. We use this method routinely in our laboratory to find compounds responsible for a contamination. It is a powerful tool for off flavor identification by comparison between a reference and a contaminated sample. The method can be used with any type of data system and any chromatographic instrument coupled to a mass spectrometer.

Più fonti

Tesi sul tema "Gaz chromatography Masss Spectrometry (GC-MS)":

Asres, Daniel Derbie. "Characterization of carbohydrates using gas chromatography/mass spectrometry (GC/MS)". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0001/MQ41677.pdf.

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Lu, Yao. "Forensic Applications of Gas Chromatography-Differential Mobility Spectrometry, Gas Chromatography/Mass Spectrometry, and Ion Mobility Spectrometry with Chemometric Analysis". Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1267816777.

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De, Vos Betty-Jayne. "Gas chromatography coupled with ion trap mass spectrometry (GC-MS and GC-MS-MS) - for arson debris analysis". Diss., Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-02082006-160506.

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Skinner, Michael A. "Hapsite® gas chromatograph-mass spectrometer (GC/MS) variability assessment /". Download the thesis in PDF, 2005. http://www.lrc.usuhs.mil/dissertations/pdf/Skinner2005.pdf.

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Milo, John A. "Quantitation of Halogenated Anisoles in Wine via SPME – GC/MS". Connect to resource online, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1230924488.

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Moulay, Valentin. "Recherche de chimie prébiotique et d'indices de vie sur les mondes océans par analyse in situ de matière organique". Electronic Thesis or Diss., université Paris-Saclay, 2023. http://www.theses.fr/2023UPASP092.

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La présence d'océans sous la surface de certains des satellites glacés de Jupiter (e.g. Europe) et de Saturne (e.g. Titan, Encelade) couplée à l'existence de geysers permettant l'échantillonnage de leurs profondeurs a fait émerger le fort potentiel exobiologique de ces corps planétaires du système solaire. De telles découvertes ont suscité le développement de futures missions spatiales (Dragonfly pour Titan et concepts de missions pour Europe et Encelade) pour comprendre la chimie de surface de ces mondes-océan, et par extension de rechercher des traces de chimie prébiotique ou de vie passée ou actuelle. La quête de telles signatures nécessite un analyseur chimique à bord des sondes qui seront envoyées dans le système solaire externe. De nombreuses techniques analytiques peuvent être mises en œuvre mais la chromatographie en phase gazeuse couplée à la spectrométrie de masse (CPG-SM) apparaît comme une technique de premier choix pour tenter de répondre à ces questions, de par son héritage dans l'exploration spatiale, sa capacité à analyser une large gamme de composés organiques et son potentiel pour détecter des biosignatures notamment par l'étude de l'énantiomérie des espèces chirales.L'objectif de ce travail de thèse est de préparer la future analyse chimique in situ de ces lunes glacées, d'une part par l'amélioration des connaissances scientifiques et d'autre part par l'optimisation technique des instruments. Il s'agit d'évaluer et d'optimiser les capacités analytiques de la CPG-SM et des méthodes de préparation d'échantillon associées, afin de détecter des molécules organiques et biosignatures avec les contraintes analytiques connues et/ou attendues sur ces corps planétaires (richesse en matière organique des échantillons prélevés pour Titan et présence d'eau de sels pour les échantillons à la surface d'Europe et d'Encelade). Dans le cas d'Europe et Encelade, l'étude d'échantillons hypersalins terrestres a permis de mettre en avant les capacités de la CPG-SM et des méthodes de prétraitements associées pour la recherche de molécules organiques d'intérêt pour l'exobiologie malgré la présence de sels. Pour évaluer l'impact du sel sur ces méthodes, le développement d'un protocole de dessalement a été entrepris et mis en place. Outre l'aspect analytique, mon travail a permis la sélection et la caractérisation des performances des colonnes chromatographiques (générale et chirale) qui seront intégrées à l'instrument DraMS à bord de la sonde Dragonfly (e.g. Dragonfly Mass Spectrometer, DraMS). Pour ces différents aspects, ce travail s'est appuyé sur l'étude d'échantillon analogues synthétiques (tholins pour Titan) mais aussi naturels (lac hypersalin pour Europe et Encelade)
The presence of oceans beneath the surface of some of Jupiter's (e.g. Europa) and Saturn's (e.g. Titan, Enceladus) icy satellites, coupled with the existence of geysers that allow their depths to be sampled, has highlighted the strong exobiological potential of these planetary bodies in the solar system. Such discoveries have motivated the development of future space missions (Dragonfly for Titan and mission concepts for Europa and Enceladus) to understand the surface chemistry of these ocean worlds, and by extension to search for traces of prebiotic chemistry or past or present life. The search for such signatures requires a chemical analyzer on board the probes that will be sent into the outer solar system. Many analytical techniques can be used, but gas chromatography-mass spectrometry (GC-MS) appears to be one of the best techniques for answering these questions, thanks to its heritage in space exploration, its ability to analyze a wide range of organic compounds, and its potential for detecting biosignatures, especially by studying the enantiomery of chiral species.The aim of this thesis is to prepare for future in situ chemical analysis of these icy moons, both by improving our scientific knowledge and by technically optimizing our instruments. The main purpose is to evaluate and optimize the analytical capabilities of GC-MS and associated sample preparation methods, in order to detect organic molecules and biosignatures within the analytical constraints known and/or expected on these planetary bodies (richness in organic matter in samples from Titan, and presence of water and salts in samples from the surface of Europa and Enceladus, etc.). In the case of Europa and Enceladus, the study of hypersaline terrestrial samples has highlighted the ability of GC-MS and associated pretreatment methods to find organic molecules of interest for exobiology, despite the presence of salts. In order to assess the impact of salt on these methods, a desalination protocol was developed and implemented. In addition to the analytical aspect, my work has enabled the selection and characterization of the performance of the chromatographic columns (general and chiral) that will be integrated into the DraMS instrument on board the Dragonfly probe (e.g. Dragonfly Mass Spectrometer, DraMS). For these different aspects, this work was based on the study of synthetic analogous samples (tholins for Titan) as well as natural ones (hypersaline lake for Europa and Enceladus)

Miranda, e. Silva Lígia Maria 1982. "Validação de método de análise de multiresíduos de defensivos agrícolas por GC-MS/MS e LC-MS/MS". [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254815.

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Orientador: Marcelo Alexandre Prado
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-21T09:52:53Z (GMT). No. of bitstreams: 1 MirandaeSilva_LigiaMaria_M.pdf: 148256 bytes, checksum: 789cac2002bb2e8dcb1bf70832d395b6 (MD5) Previous issue date: 2012
Resumo: O crescente aumento populacional em escala mundial, tornou necessário um grande esforço por parte da agricultura para aumentar, a cada ano, a produção de alimentos para atender as necessidades do mercado externo e interno do Brasil. Recursos técnicos e científicos passaram então, a serem aplicados em busca da melhoria na produção dos cultivos,principalmente mediante o uso de fertilizantes e praguicidas. Com isso, a sociedade se deparou com problemas de ordem de equilíbrio ambiental e saúde pública, pois devido à contínua diversificação dos fitoparasitas, surgem, a todo momento, reduções do período de tempo entre aplicações consecutivas, e mais importante talvez, usos de doses mais altas e emprego simultâneo de diferentes pesticidas, por parte dos agricultores, objetivando complementar ações específicas ou alcançar efeitos sinérgicos para maiores rendimentos na produção. Tal situação traz como conseqüência óbvia e direta, o aumento, inaceitável, dos riscos de contaminação do meio ambiente com resíduos químicos de defensívos da área agropecuarista prejudiciais à saúde, o que leva a inúmeros problemas relativos à segurança alimentar dos produtos consumidos, e à uma preocupação de âmbito nacional evidenciada pela criação do Programa de Análise de Resíduos de Agrotóxicos em alimentos (PARA) da ANVISA. O aumento na necessidade de detecção e quantificação destes compostos, acarretou o desenvolvimento de pesquisas no setor, a fim de atingir uma melhoria na eficiência,qualidade e rapidez de resposta nas análises. A possibilidade do estudo de não apenas um de cada vez, mas de até 300 compostos sendo extraídos, detectados e quantificados simultâneamente se tornou a saída mais viável, tanto qualitativa quanto economicamente, facilitando o monitoramento contínuo do fornecimento de produtos do setor alimentício pelos chamados métodos multiresíduos. O presentre trabalho teve como princípio a validação de um método multiresíduo para análise de 14 analitos usando uma técnica de alto poder de concentração e limpeza do extrato como o GPC (Gel Permeation Chromatography) e detecção e quantificação por GC-MS/MS e LC-MS/MS. Os pesticidas investigados englobam classes como: acaricidas, inseticidas, fungicidas, nematicidas e formicidas de aplicação foliar, em sementes ou em solo, sendo que o acefato, metamidofós, acetamiprido e o thiamethoxan foram extraídos de amostras de batata e feijão e analisados por LC-MS/MS e a azoxistrobina, bifentrina, carbofuran, chlorotalonil, clorpirifós, clorfenapir, etofenprox, famoxadone,metalaxil, procimidone e o tebuconazole em amostras de batata e tomate e analisados por GCMS/MS. Os limites de detecção (LD) encontrados variaram de 0,06 a 2,89µg/L, e os coeficientes de variação (CV), de 0,036 a 2,036%. As recuperações foram determinadas em cada tipo de amostras, e os valores encontrados estavam entre 93,34% e 109,67%. Nenhuma das matrizes utilizadas apresentaram resultados insatisfatórios e o método utilizado mostrouse robusto e de fácil aplicação para todos os analitos testados
Abstract: The growing population worldwide, has required a great effort on the part of agriculture to increase each year, the production of food to meet the needs of external and internal market of Brazil. Technical and scientific resources spent then, to be applied in pursuit of improved crop production, mainly through the use of fertilizers and pesticides.With this, the company encountered problems in the balance of environmental and public health, since due to the continuous diversification of plant parasites, arise at any moment,reductions in the time period between consecutive applications, and perhaps most important,uses more doses high and simultaneous use of different pesticides by farmers, aiming to complete specific actions or to achieve synergistic effects in producing higher yields. This situation brings obvious and direct consequence, the increase unacceptable risk of environmental contamination with chemical residues from pesticides in farms are harmful to health, which leads to numerous problems relating to food safety of the products consumed, and to a concern nationwide evidenced by the creation of the Program Analysis of Pesticide Residues in Food (TO) of ANVISA. The increase in the necessity for detection and quantification of these compounds, led the development of research in the sector in order to achieve an improvement in efficiency, quality and responsiveness in the analyzes. The possibility of studying not just one at a time, but up to 300 compounds being extracted,detected and quantified simultaneously output became more viable, both qualitatively and economically, facilitating continuous monitoring of the supply of products by the food industry called methods multiresidue. The principle presentre work was the validation of a multiresidue method for analysis of 14 analytes using a technique of high power concentration and cleanup of the extract as GPC (Gel Permeation Chromatography) and detection and quantification by GC-MS/MS and LC- MS / MS. The pesticides investigated include classes such as acaricides, insecticides, fungicides, insecticides and nematicides foliar, seed or soil,and acephate, methamidophos, and Acetamiprid thiamethoxan were extracted from samples of potatoes and beans and analyzed by LC-MS / MS and azoxystrobin, bifenthrin, carbofuran,chlorothalonil, chlorpyrifos, chlorfenapyr, etofenprox, famoxadone, metalaxyl, procymidone and tebuconazole in samples of potato and tomato and analyzed by GC-MS/MS. The limits of detection (LOD) ranged from 0.06 to 2.89 mg / L, and the coefficients of variation (CV), 0.036 to 2.036%. The recoveries were determined for each type of samples, and the values were between 93.34% and 109.67%. None of the arrays used had unsatisfactory results and method proved to be robust and easy to apply for all analytes tested
Mestrado
Ciência de Alimentos
Mestra em Ciência de Alimentos

Nezami, Ranjbar Mohammad Rasoul. "Novel Preprocessing and Normalization Methods for Analysis of GC/LC-MS Data". Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/73499.

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We introduce new methods for preprocessing and normalization of data acquired by gas/liquid chromatography coupled with mass spectrometry (GC/LC-MS). Normalization is desired prior to subsequent statistical analysis to adjust variabilities in ion intensities that are not caused by biological differences. There are different sources of experimental bias including variabilities in sample collection, sample storage, poor experimental design, noise, etc. Also, instrument variability in experiments involving a large number of runs leads to a significant drift in intensity measurements. We propose new normalization methods based on bootstrapping, Gaussian process regression, non-negative matrix factorization (NMF), and Bayesian hierarchical models. These methods model the bias by borrowing information across runs and features. Another novel aspect is utilizing scan-level data to improve the accuracy of quantification. We evaluated the performance of our method using simulated and experimental data. In comparison with several existing methods, the proposed methods yielded significant improvement. Gas chromatography coupled with mass spectrometry (GC-MS) is one of the technologies widely used for qualitative and quantitative analysis of small molecules. In particular, GC coupled to single quadrupole MS can be utilized for targeted analysis by selected ion monitoring (SIM). However, to our knowledge, there are no software tools specifically designed for analysis of GS-SIM-MS data. We introduce SIMAT, a new R package for quantitative analysis of the levels of targeted analytes. SIMAT provides guidance in choosing fragments for a list of targets. This is accomplished through an optimization algorithm that has the capability to select the most appropriate fragments from overlapping peaks based on a pre-specified library of background analytes. The tool also allows visualization of the total ion chromatogram (TIC) of runs and extracted ion chromatogram (EIC) of analytes of interest. Moreover, retention index (RI) calibration can be performed and raw GC-SIM-MS data can be imported in netCDF or NIST mass spectral library (MSL) formats. We evaluated the performance of SIMAT using several experimental data sets. Our results demonstrate that SIMAT performs better than AMDIS and MetaboliteDetector in terms of finding the correct targets in the acquired GC-SIM-MS data and estimating their relative levels.
Ph. D.

Zhai, Lailiang. "Gas Chromatography: Mass Spectrometry of Chemical Agents and Related Interferents". Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1266.pdf.

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Christison, Krege Matthew. "Exploring the Molecular Origin of Jet Fuel Thermal Oxidative Deposition Through Statistical Analysis of Mass Spectral Data and Pyrolysis Gas Chromatography/Mass Spectrometry of Deposits". Scholarly Commons, 2019. https://scholarlycommons.pacific.edu/uop_etds/3639.

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ASTM D3241 (Standard Test Method for Thermal Oxidation Stability of Aviation Turbine Fuels) measures the thermal oxidative stability of jet fuels under elevated temperature and pressure conditions. When jet fuels fail ASTM D3241, either at the refinery or in the distribution system, there can be supply disruptions and financial losses. Understanding the causes of poor thermal oxidative stability in jet fuels could help prevent or mitigate issues. In order to develop a deeper understanding of the molecular precursors that lead to ASTM D3241 failures, a number of analytical methodologies and data treatment techniques have been developed, applied, and reported here. Statistical analysis of LC/MS ESI data from jet fuels with varying thermal oxidative stabilities allows for the identification of molecules that are significant to ASTM D3241 failures. Differential statistical analysis of LC/MS ESI data from jet fuels before and after thermal oxidative stressing in a QCM reactor elucidates which significant molecules are being consumed during oxidation and which molecules are increasing in abundance. The analysis of thermal oxidative deposits that form during thermal oxidative stressing in the QCM reactor allows for the insight into the molecular components of the deposits. Attapulgus clay removes the polar molecules that lead to thermal oxidative stability issues in the refinery. Extraction of Attapulgus clay that has been used in a refinery to filter jet fuel with a series of solvents removes the polar molecules into a series of fractions. The subsequent analysis of the fractions by comprehensive GCxGC/MS leads to the identification of the different homologous series of molecules that are removed by the clay. The analyses developed and employed here are shown to be particularly useful for the analysis of trace polar nitrogen and oxygen containing molecules. Similar homologous series of molecules are identified across all of the different analyses. It is also clear from some of the analyses, along with previously reported data in the literature, that reactive sulfur-containing molecules are significant to poor thermal oxidative stability as measured by ASTM D3241 and to the formation of thermal oxidative deposits. There is still an opportunity to find methodologies to better characterize the sulfur species present and correlate them to the data that is reported here.

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Libri sul tema "Gaz chromatography Masss Spectrometry (GC-MS)":

McMaster, Marvin. GC/MS. New York: John Wiley & Sons, Ltd., 2008.

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McMaster, Marvin C. GC/MS: A practical user's guide. New York: Wiley, 1998.

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Hübschmann, Hans-Joachim. Handbook of GC/MS: Fundamentals and applications. Weinheim: Wiley-VCH, 2001.

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Hübschmann, Hans-Joachim. Handbook of GC/MS: Fundamentals and applications. 2^a ed. Weinheim: Wiley-VCH, 2009.

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Oehme, Michael. Pratical introduction to GC-MS analysis with quadrupoles. A cura di Dünges Wolfgang. Hüthig: Heidelberg, 1999.

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Yancey, M. F. Capillary column GC-MS determination of 77 purgeable organic compounds in two simulated liquid wastes. Cincinnati, OH: U.S. Environmental Protection Agency, Environmental Monitoring and Support Laboratory, 1988.

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Capitoli di libri sul tema "Gaz chromatography Masss Spectrometry (GC-MS)":

Rivier, L. "GC-MS of Auxins". In Gas Chromatography/Mass Spectrometry, 146–88. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-82612-2_8.

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Witte, L. "GC-MS Methods for Terpenoids". In Gas Chromatography/Mass Spectrometry, 134–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-82612-2_7.

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Kodama, H. "GC-MS Methods for Tobacco Constituents". In Gas Chromatography/Mass Spectrometry, 277–98. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-82612-2_12.

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Combaut, G. "GC-MS of Plant Sterol Analysis". In Gas Chromatography/Mass Spectrometry, 121–33. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-82612-2_6.

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Palni, L. M. S., S. A. B. Tay e J. K. MacLeod. "GC-MS Methods for Cytokinins and Metabolites". In Gas Chromatography/Mass Spectrometry, 214–53. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-82612-2_10.

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Kameoka, H. "GC-MS Method for Volatile Flavor Components of Foods". In Gas Chromatography/Mass Spectrometry, 254–76. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-82612-2_11.

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Nyberg, H. "GC-MS Methods for Lower Plant Glycolipid Fatty Acids". In Gas Chromatography/Mass Spectrometry, 67–99. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-82612-2_4.

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Medeiros, Patricia M. "Gas Chromatography-Mass Spectrometry (GC-MS)". In Encyclopedia of Earth Sciences Series, 1–6. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-39193-9_159-1.

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Medeiros, Patricia M. "Gas Chromatography–Mass Spectrometry (GC–MS)". In Encyclopedia of Earth Sciences Series, 530–35. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-39312-4_159.

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Shillito, Lisa-Marie. "Gas Chromatography - Mass Spectrometry (GC/MS)". In Archaeological Soil and Sediment Micromorphology, 399–401. Chichester, UK: John Wiley & Sons, Ltd, 2017. http://dx.doi.org/10.1002/9781118941065.ch37.

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Atti di convegni sul tema "Gaz chromatography Masss Spectrometry (GC-MS)":

Oizumi, Hiroaki, Kazuyuki Matsumaro, Julius Santillan e Toshiro Itani. "Evaluations of EUV resist outgassing by gas chromatography mass spectrometry (GC-MS)". In SPIE Advanced Lithography, a cura di Bruno M. La Fontaine. SPIE, 2010. http://dx.doi.org/10.1117/12.846269.

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Blebea, Nicoleta Mirela, e Simona Negreș. "METHODS FOR QUANTIFICATION OF THE MAIN CANNABINOIDS IN CBD OIL". In GEOLINKS Conference Proceedings. Saima Consult Ltd, 2021. http://dx.doi.org/10.32008/geolinks2021/b1/v3/13.

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Cannabidiol (CBD) is an alkaloid present in Cannabis sativa, together with tetrahydrocannabinol (THC) and more than 120 other substances belonging to a group of compounds named cannabinoids. Due to the continuous increased usage of CBD oils, it became necessary to be developed efficient methods for the identification of its compounds and especially for the characterization of the cannabinoids from the commercial specimens. Cannabinoids may be detected by many and different analytical methods, including immunoassays (EMIT®, Elisa, fluorescent polarization, radioimmunotest), techniques of flat chromatography: classic thin layer chromatography (TLC), optimum performance laminar chromatography (OPLC) and multiple development automatization (AMD), gas chromatography-mass spectrometry (GC-MS), high-performance liquid chromatography-mass spectrometry (HPLC-MS). Ultraviolet signal (UV) is used for the quantification of major cannabinoids and the mass spectrometer is used for the quantification of minor cannabinoids. The purpose of this study was to compare the performances of TLC, Ultra High-Performance Liquid chromatography with Photodiode Array Detection (UHPLC with PDA) and LC-MS/ MS technique for the qualitative and quantitative determination of cannabinoids in 3 commercial oils with CBD. Having in view that CBD may be found in many forms of oils, on the legal market of the internet, we believe that the development of a method for the qualitative and quantitative determination may be an interesting subject for the pharmaceutical professional persons.

Jarassova, Tolganay, e Mehmet Altunsoy. "Organic Geochemical Characteristics of Core Samples from Central Primorsk-Emba Province, Precaspian Basin, Kazakhstan". In SPE Annual Caspian Technical Conference. SPE, 2021. http://dx.doi.org/10.2118/207044-ms.

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Abstract The Primorsk-Emba province is one of the main oil and gas region of the Precaspian basin. The resources of the Primorsk-Emba oil and gas region range from 5 to 12 billion tons of oil and from 2 to 6 trillion m³ of natural gas. This study primarily concentrates on investigating the organic geochemistry and petroleum geology characteristics of sedimentary units that generated oil in the central Primorsk-Emba province. 20 core samples taken from the Jurassic units in the western part of the study area are characterized by organic matter amount, hydrocarbon production potential, type of organic matter, maturity of organic matter. According to the Rock-Eval results Jurassic aged rocks generally have a petroleum potential ranging from weak to excellent, the organic matter is between Type II (oil prone), Type II-III (gas-oil prone) and Type III (gas prone), and the degree of maturation is immature-mature stage. Oil extracts were characterized by geochemical methods including Gas Chromatography (GC) and Gas Chromatography–Mass Spectrometry (GC–MS). n-alkanes and isoprenoids were evaluated by High-Resolution Gas Chromatography (GC-HR), aromatic hydrocarbons were evaluated by Low Thermal Mass Gas Chromatography (GC-LTM), terpanes (hopanes), steranes / diasteranes and aromatic hydrocarbons were evaluated by Gas Chromatography-Mass Spectrometry (GC-MS). The GC and GC-MS data obtained, it has been determined whether the paleoenvironment characteristics of the study area, hydrocarbon potential, type of kerogen, maturity level of organic matter and whether it is affected by biodegradation. Distribution of n-alkanes in the GC showed that no biodegradation was observed in analyzed samples, source rock deposited in a marine environment under reducing conditions and an organic matter that occurred were generated by marine carbonates. Based on maturity parameters, studied oils are mature and located on the oil generation window. According to biomarker age parameters C28 / C29 and norcholestane (NCR)/nordiacholestane (NDR) samples are generally Mesozoic (Triassic-Jurassic- Cretaceous) origin, nevertheless there are also levels corresponding to the Paleozoic (Permian) late stages.

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Basa, E. L. U., H. Julendra, A. Abinawanto, A. Sofyan e A. Sophian. "Analysis of organic acids from Lactobacillus plantarum with gas chromatography-mass spectrometry (GC-MS)". In PROCEEDINGS OF THE 4TH INTERNATIONAL SYMPOSIUM ON CURRENT PROGRESS IN MATHEMATICS AND SCIENCES (ISCPMS2018). AIP Publishing, 2019. http://dx.doi.org/10.1063/1.5132522.

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Opsal, Richard, Kevin Owens e James P. Reilly. "Chromatographic effluent detection with laser ionization mass spectrometry". In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/oam.1985.thm2.

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It has been well established during the past decade that atoms and molecules can be efficiently ionized by illuminating them with intense pulses of laser radiation and that spectroscopic information about neutral molecules1 and ions2 can be extracted. One of the major achievements of analytical science, the detection of single atoms, has been achieved by exploiting laser ionization.3 Equivalent sensitivity toward molecules is certainly attainable in principle. However practical systems for detecting molecules must overcome problems associated with background ionization and excited-state molecule dynamics. To increase the detection selectivity made possible by the laser ionization process, sample molecules are introduced into our system through a gas or supercritical fluid chromatograph; the ions generated are mass resolved by a time-of-flight mass spectrometer.4 Recent improvements in our chromatographic systems, mass spectrometer resolution, and GC-MS interface are discussed, along with the application of these to the detection of minute quantities of various priority pollutants.

Ying, Lee Chai, e Lim Koo Foong. "Gas Chromatography Mass Spectrometry (GC-MS) application in back end semiconductor: Chemical cleaning efficiency assessment". In 2016 IEEE 18th Electronics Packaging Technology Conference (EPTC). IEEE, 2016. http://dx.doi.org/10.1109/eptc.2016.7861503.

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Nur Aidha, Novi, Retno Yunilawati e Irma Rumondang. "Method Development for Analysis of Essential Oils Authenticity using Gas Chromatography-Mass Spectrometry (GC-MS)". In 2nd International Conference of Essential Oil Indonesia. SCITEPRESS - Science and Technology Publications, 2019. http://dx.doi.org/10.5220/0009956000410046.

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Jafary, Hanieh, e Mohammad reza Kamali. "Oil to Oil Correlation Studies in Marun and Kupal Oilfields (SW of Iran) Using Gas Chromatography-Mass Spectrometry-Mass Spectrometry (GC/MS/MS)". In GEO 2010. European Association of Geoscientists & Engineers, 2010. http://dx.doi.org/10.3997/2214-4609-pdb.248.364.

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McGrath, Thomas, Adrian Covaci, Els Van Hoeck, Franck Limonier, Giulia Poma, Jasper Bombeke, Kevin Vanneste, Laure Joly, Mirjana Andjelkovic e Raf Winand. "Gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-high resolution mass spectrometry (LC-HRMS) approaches for analysis of chlorinated paraffins in edible fats and oils". In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/wycg9726.

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Chlorinated paraffins (CPs) are high production volume chemicals composed of complex mixtures of thousands of compounds that have been applied widely as flame retardants and plasticizers. CPs have demonstrated toxic and bioaccumulative properties, while evidence suggests dietary intake to constitute a major pathway for human exposure. This study reports on the optimization and validation of an analytical method for the quantification of short- and medium-chained CPs (SCCPs and MCCPs, respectively) using gas chromatography-mass spectrometry (GC-MS) in fats and oils, and the development of liquid chromatography-high resolution mass spectrometry (LC-HRMS) methods for investigation of long chain CP (LCCP) occurrence. Extraction was performed by ultrasonication in n-hexane and dichloromethane followed by sulphuric acid and acidified silica cleanup and fractionation on neutral silica to remove potentially interfering organohalogen contaminants. Quantification of GC-MS results using a chlorine-content calibration procedure was assessed via repeated analysis (n=3) of olive oil fortified with SCCP and MCCP technical mixtures at two concentration levels and spiked lard samples from a recent European Union Reference Laboratory (EURL) interlaboratory study. The average accuracy ranged from 76 to 126% in the olive oil samples and from 57 to 150% in fortified lard, meeting the EURLs acceptability criteria for all tests, while the precision was < 15%. The applicability of the method was demonstrated by analysis of 26 fats and oil samples purchased in Belgium. SCCPs were detected in 31% of samples, ranging < LOQ to 19 ng/g, and MCCPs were present in 85%, ranging < LOQ to 190 ng/g. Each of four samples selected for homologue profiling by LC-HRMS were also found to contain LCCPs. This research demonstrates reliable methods for CP analysis in fats and oils and highlights the potential for contamination of these products by CPs. Fats and oils appear to be substantial contributors to overall human exposure to CPs.

Rapporti di organizzazioni sul tema "Gaz chromatography Masss Spectrometry (GC-MS)":

Kimble, Ashley, Derek Muensterman, Liliana Cahuas, Ivan Titaley, Jennifer Field, Anthony Bednar e Lee Moores. Extraction and analysis of per- and polyfluoroalkyl Substances (PFAS) from Meals Ready-to-Eat (MRE) films using GC-MS and LC-MS/MS. Engineer Research and Development Center (U.S.), maggio 2023. http://dx.doi.org/10.21079/11681/47114.

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This work was in response to the Defense Logistic Agency’s (DLA) Subsistence Network Broad Agency Announcement, BAA-0003-16 addressing 2019 NDAA Section 329 that states packaging materials used for Meals Ready-to-Eat (MRE) that contact food products must be free of per- and polyfluoroalkyl substances (PFAS). This was addressed by determining the presence or absence of PFAS on MREs by extraction followed by gas chromatography mass spectrometry (GC-MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS). Any samples positive for PFAS were quantitated using LC triple quadrupole (QqQ) MS at the US Army Engineering and Research Development Center (ERDC) and by high resolution quadrupole time-of-flight (qTOF) MS and GC-MS at Oregon State University (OSU).

Wood, William F., David L. Largent e Darvin A. DeShazer. The cooked shellfish-odour of the mushroom Russula xerampelina. Verlag der Österreichischen Akademie der Wissenschaften, gennaio 2024. http://dx.doi.org/10.1553/biosystecol.3.e115244.

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The “shrimp mushroom”, Russula xerampelina, has a strong cooked shellfish odour. Headspace volatiles from fresh sporocarps of this mushroom were analysed using solid phase microextraction (SPME) and gas chromatography–mass spectrometry (GC–MS). Trimethylamine and trimethylamine N-oxide were the only volatile compounds detected emanating from the fruiting body. Trime- thylamine is noted for its fishy, cooked crab or cooked shrimp-like odour.

Skinner, Michael A. HAPSITE (registered trademark) Gas Chromatograph/Mass Spectrometer (GC/MS) Variability Assessment. Fort Belvoir, VA: Defense Technical Information Center, maggio 2004. http://dx.doi.org/10.21236/ad1014554.

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Tappan, D. V., e E. Heyder. A GC/MS (Gas Chromatographic/Mass Spectrometric) Analysis for Trimethylolpropane Phosphate on Aircraft Hoses. Fort Belvoir, VA: Defense Technical Information Center, maggio 1988. http://dx.doi.org/10.21236/ada198977.

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Bora. PR-004-14604-R01 Miniaturized Gas Chromatography and Gas Quality Sensor. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), giugno 2015. http://dx.doi.org/10.55274/r0010869.

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The natural gas industry currently relies on gas chromatography to evaluate the composition of natural gas including alkanes, carbon dioxide, nitrogen, and oxygen. The higher and lower heating values, Wobbe Index, Hydrocarbon Dewpoint, Methane Number, and viscosity are all calculated from the gas composition. The need to understand the composition of fuel gas and to monitor its components is crucial to the natural gas industry. Monitoring the composition of the fuel gas provides the industry with the capability of protecting valuable underground assets, delivering gas that meets end-usage requirements, and tracking of constituents for both billing purposes and to ensure compliance with tariff agreements. As with any technology, there are limitations to gas chromatography. Limitations can include high cost, time delay, inability to sample at high pressure, and selectiveness of gas chromatography detectors. This project consisted of a technology assessment of currently available and emerging technologies including micro gas chromatographs, optical spectrometers, and mass spectrometers for their ability to determine gas composition compared to current GC technology. Technologies were investigated and assessed by their analytical characteristics (what components they could analyze and detection limits), their sampling characteristics (sampling pressure limits, scan time, and emissions), and their operational characteristics (availability, cost, consumables, maintenance, and packaging). Recommendations for further testing were made on the technologies whose characteristics showed the most promise for analysis of natural gas at custody transfer points.

Smith, Jonell, Michael White, Robert Bernstein e James Hochrein. Identification of volatile butyl rubber thermal-oxidative degradation products by cryofocusing gas chromatography/mass spectrometry (cryo-GC/MS). Office of Scientific and Technical Information (OSTI), febbraio 2013. http://dx.doi.org/10.2172/1093689.

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Mulcahy, H., e C. Koester. Experiments with the LECO Pegasus Gas Chromatograph/ Time-of-Flight Mass Spectrometer Phase 1: Fast GC Separations and Comparison of the GC/TOF-MS with Conventional Quadrupole GC/MS and Fast Quadrupole GC/MS. Office of Scientific and Technical Information (OSTI), agosto 2012. http://dx.doi.org/10.2172/1056608.

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Christensen, Earl, Jack Ferrell, Mariefel V. Olarte e Asanga B. Padmaperuma. Quantification of Semi-Volatile Oxygenated Components of Pyrolysis Bio-Oil by Gas Chromatography/Mass Spectrometry (GC/MS). Laboratory Analytical Procedure (LAP). Office of Scientific and Technical Information (OSTI), marzo 2016. http://dx.doi.org/10.2172/1241093.

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Roskamp, Melissa. Characterization of Secondary Organic Aerosol Precursors Using Two-Dimensional Gas Chromatography with Time of Flight Mass Spectrometry (GC×GC/TOFMS). Portland State University Library, gennaio 2000. http://dx.doi.org/10.15760/etd.1411.

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Conrady, Morgan, Markus Bauer, Kyoo Jo, Donald Cropek e Ryan Busby. Solid-phase microextraction (SPME) for determination of geosmin and 2-methylisoborneol in volatile emissions from soil disturbance. Engineer Research and Development Center (U.S.), ottobre 2021. http://dx.doi.org/10.21079/11681/42289.

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A method is described here for the concentration and determination of geosmin and 2-methylisoborneol (2-MIB) from the gaseous phase, with translation to field collection and quantification from soil disturbances in situ. The method is based on the use of solid-phase microextraction (SPME) fibers for adsorption of volatile chemicals from the vapor phase, followed by desorption into a gas chromatograph-mass spectrometer (GC-MS) for analysis. The use of a SPME fiber allows simple introduction to the GC-MS without further sample preparation. Several fiber sorbent types were studied and the 50/30 μm DVB/CAR/PDMS was the best performer to maximize the detected peak areas of both analytes combined. Factors such as extraction temperature and time along with desorption temperature and time were explored with respect to analyte recovery. An extraction temperature of 30 ◦C for 10 min, with a desorption temperature of 230 ◦C for 4 min was best for the simultaneous analysis of both geosmin and 2-MIB without complete loss of either one. The developed method was used successfully to measure geosmin and 2-MIB emission from just above disturbed and undisturbed soils, indicating that this method detects both compounds readily from atmospheric samples. Both geosmin and 2-MIB were present as background concentrations in the open air, while disturbed soils emitted much higher concentrations of both compounds. Surprisingly, 2-MIB was always detected at higher concentrations than geosmin, indicating that a focus on its detection may be more useful for soil emission monitoring and more sensitive to low levels of soil disturbance.