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The Quantitative Analysis Of Biogenic Volatile Organic Compounds From Live Tree Species In An Enclosure Utilizing The Solid Phase Micro Extraction Spme Sample Collection Technique
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Book Synopsis The Quantitative Analysis of Biogenic Volatile Organic Compounds from Live Tree Species in an Enclosure Utilizing the Solid Phase Micro Extraction (SPME) Sample Collection Technique by : Mark Michael Sinnott
Download or read book The Quantitative Analysis of Biogenic Volatile Organic Compounds from Live Tree Species in an Enclosure Utilizing the Solid Phase Micro Extraction (SPME) Sample Collection Technique written by Mark Michael Sinnott and published by . This book was released on 2009 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Solid-Phase Microextraction of VOCs in Water by : V. Mani
Download or read book Solid-Phase Microextraction of VOCs in Water written by V. Mani and published by . This book was released on 1996 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The measurement of very low concentrations of organic compounds in the environment has been a subject of research for many years. Recently, the sample preparation in the analysis of aqueous samples has been achieved by solid phase microextraction (SPME). This method has been shown to be fast, inexpensive, solventless, portable and automatable. SPME has several advantages over conventional liquid-liquid extraction. SPME has been shown to be a quantitative technique for volatile and semivolatile compounds from gaseous and liquid samples. The quantization by SPME is also linear over four orders of magnitude. As this method can reach a detection limit of 15 ppt (parts per trillion) for several compounds and can be easily automated, the analysis of volatile organic compounds (VOCs) in the environment, in particular, water samples, is highly advantageous by this method. This study will describe the analysis of volatile organics, BTEX, and halogenated organics in water. The lowest limit of detection, linearity, and other parameters will be discussed. The analysis of a soil sample taken near an oil storage tank for VOCs by SPME will be described. A comparison between different fibers (different types of coating materials and film thickness) using different columns will be described in this work.
Book Synopsis Quantitative Analysis of Volatile and Semivolatile Organic Compounds in Air with Solid Phase Microextraction by : Abir Khaled
Download or read book Quantitative Analysis of Volatile and Semivolatile Organic Compounds in Air with Solid Phase Microextraction written by Abir Khaled and published by . This book was released on 1999 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Plant Volatile Analysis by : Hans F. Linskens
Download or read book Plant Volatile Analysis written by Hans F. Linskens and published by Springer Science & Business Media. This book was released on 1997-04-16 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book covers a vast array of methods for the analysis of volatile compounds exuded by plants. Some of these volatiles are of great commercial importance, including the aromas of wines and teas, and volatiles in fruits. Other volatiles such as essential oils can be useful for chemotaxonomic purposes, and a chapter on an emerging method, that of chemometric analysis of such data, is included. Isoprene and ammonia rarely find a place in analytical methods presented for plant materials, but methods for these volatiles are described in this book. The volatiles given off by flowers are also included, and in situ headspace analysis of these volatiles is described, a method of potential use for the study of insect-plant interactions.
Book Synopsis Volatile Organic Compound Analysis in Biomedical Diagnosis Applications by : Raquel Cumeras
Download or read book Volatile Organic Compound Analysis in Biomedical Diagnosis Applications written by Raquel Cumeras and published by CRC Press. This book was released on 2018-11-09 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents a thought-provoking state-of-the-art picture of how volatile compounds are used in metabolomics, currently a hot topic in the metabolomics field. It provides a thorough description of what volatile organic compounds (VOCs) are, why they are important in biomedicine, and what the analytical platforms are used. It also looks at multivariate analysis and databases needs. Because VOCs are end-up compounds of metabolic processes, volatiles can be linked to different diseases or pathologies for both diagnosis and prognosis. The authors provide authoritative information and guidance on the analytical and statistical techniques used and how to identify, and they review the main current areas of application, which include breath metabolomics, cancer diagnosis, and microbial volatiles. Key Features: Presents a thorough overview of volatile research in biomedical applications Examines both gold standard techniques (metabolomics based) and artificial olfactory systems Reviews all aspects of volatile metabolites in biomedicine research, from origin to detection platforms Describes relevant diseases diagnosis and prognosis achievements, including cancer
Book Synopsis Determination of Volatiles from Fungi and Plants: Challenges and Limitations of a HS SPME GC-MS Method for Quantification by : Alexandra Fiebrich
Download or read book Determination of Volatiles from Fungi and Plants: Challenges and Limitations of a HS SPME GC-MS Method for Quantification written by Alexandra Fiebrich and published by . This book was released on 2011 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: Die Analyse von 28 flüchtigen organischen Verbindungen (VOC) die in Pflanzen und Pilzen vorkommen, wurde in dieser Masterarbeit dargestellt. Die verwendete analytische Technik war Gaschromatographie (GC) gekoppelt mit Massenspektrometrie (MS). Die Analyten wurden mittels Festphasen Miktroextraktion (SPME) aus dem Gasraum (HS) extrahiert. Die experimentell ermittelten Massspektren und berechneten Retentionsindizes wurden zur Erstellung einer hausinternen Datenbank verwendet. Die Datenbankeinträge wurden mit physikalischen Informationen z.B. Schmelz- und Siedepunkt und dem Molekulargewicht versehen. Für die Evaluierung der Methodencharakteristika war die Bestimmung des linearen Konzentrationsbrereiches von sieben ausgewählten Substanzen - jede repräsentierte eine chemische Gruppe - für die weitere externe Kalibrierung erforderlich. Die Matrixeinflüsse des Standardgemischs und des Nährmediums mussten ermittelt werden. Für den Matrixeffekt des Standardgemischs wurden die sieben Substanzen in einer Standardlösung kombiniert und diese wurde in sieben Verdünnungen gemessen. Anschließend wurden die erstellten Kalibrierkurven der Einzelsubstanzen mit denen aus dem Standardgemisch verglichen. Die Ergebnisse zeigten, dass die relative Rückmeldung (response) der Einzelsubstazen viel höher war als im Standardgemisch, d.h. die einzelnen Substanzen beeinflussen sich negativ. Ausgehend von dem Standardgemisch wurden für eine detailiertere Untersuchung der Matrixeinflüsse, 21 binäre Gemische aus den sieben Substanzen hergestellt und gemessen. Die Ergebnisse zeigten, dass z.B. 3-Octanone einen negativen (17 - 82 %) und Furan-2-ethyl einen positiven Einfluss (51 - 849 %) auf die anderen Substanzen im Gemisch hatten. Die von dem Nährmedium ausgehenden Matrixeinflüsse wurden getestet, indem die Einzelsubstanzen auf das Medium aufgebracht wurden. Nach den Messungen wurden Kalibrierkurven erstellt und mit denen der Einzelsubstanzen verglichen. Die Ergebnisse haben gezeigt, dass das Nährmedium drei verschiedene Einflüsse auf die Substanzen aufweist, nämlich: Verstärkung (113 - 2220 %), Unterdrückung (50 %) und Einheitlichkeit. Conclusio: die Matrixeinflüsse müssen vor der Quantifizierung im Detail untersucht werden.*****The analysis of 28 volatile organic compounds (VOC) occurring in plants and fungi was reported in this master thesis. The analytical technique used was gas chromatography (GC) coupled to mass spectrometry (MS). The analytes were extracted by solid phase microextraction (SPME) from the headspace (HS). The experimentally determined mass spectra and the calculated retention indices were used to build an in-house database. The database entries were equipped with physical information e.g. boiling and melting point and formula mass. For the evaluation of method characteristics the determination of the linear concentration range of seven selected substances, each representing a structural group, was necessary for the further external calibration. The matrix effects of the standard mixture and the cultivation medium had to be investigated. For the matrix effects of the standard mixture, the seven substances were combined into one standard mixture and were measured in seven dilutions. Afterwards, the established calibration curves of the single standards were compared to those standards in the standard mixture. Results showed that the relative response of the single standards was much higher than in the standard mixture i.e. that the substances affected each other in a negative way. For a more detailed investigation of the matrix effects occurring from the single substances, 21 binary mixtures of the seven substances were measured. Results showed that e.g. 3-octanone had a negative (17 - 82 %) and furan-2-ethyl had a positive (51 - 849 %) effect on the other substances in the mixture. Matrix effects occurring from the cultivation medium, were tested by applying single standard solutions on the PDA medium. After the measurements calibration cu??P????arte???P???????? can be started.
Book Synopsis The Relevance of Volatile Organic Compound Analysis Via Solid Phase Micro Extraction GC/MS Within Heritage Environments by : Mark Kearney
Download or read book The Relevance of Volatile Organic Compound Analysis Via Solid Phase Micro Extraction GC/MS Within Heritage Environments written by Mark Kearney and published by . This book was released on 2016 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Bioavailability of Contaminants in Soils and Sediments by : National Research Council
Download or read book Bioavailability of Contaminants in Soils and Sediments written by National Research Council and published by National Academies Press. This book was released on 2003-05-03 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bioavailability refers to the extent to which humans and ecological receptors are exposed to contaminants in soil or sediment. The concept of bioavailability has recently piqued the interest of the hazardous waste industry as an important consideration in deciding how much waste to clean up. The rationale is that if contaminants in soil and sediment are not bioavailable, then more contaminant mass can be left in place without creating additional risk. A new NRC report notes that the potential for the consideration of bioavailability to influence decision-making is greatest where certain chemical, environmental, and regulatory factors align. The current use of bioavailability in risk assessment and hazardous waste cleanup regulations is demystified, and acceptable tools and models for bioavailability assessment are discussed and ranked according to seven criteria. Finally, the intimate link between bioavailability and bioremediation is explored. The report concludes with suggestions for moving bioavailability forward in the regulatory arena for both soil and sediment cleanup.
Book Synopsis Terpenes and Terpenoids Determination in Present of Ozone by SPME and GC-MS by : Weiwei Hua
Download or read book Terpenes and Terpenoids Determination in Present of Ozone by SPME and GC-MS written by Weiwei Hua and published by . This book was released on 2014 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Particulate matter air pollution demonstrates adverse human health effect and is one of reasons for the climate change. Monoterpenes are a class of volatile organic compounds (VOCs), which are often present in household products. They can be produced by a variety of plants and belong to biogenic VOC (BVOC) class. Due to the fact that monoterpenes often contain one or more unsaturated carbon-carbon double bonds, they can readily react with ozone, and some of the products form PM. In order to address the potential health problems caused by the use of household products, climate change, and health effects caused by BVOC emissions, an efficient, precise, accurate and environmental friendly analytical sampling and detection method needs to be developed. In this work, a dynamic solid phase microextraction (SPME) sampling method is coupled with gas chromatography (GC)/mass spectroscopy detection for both single monoterpene and complex monoterpene mixture analysis in the presence of ozone. Not only the effects of parameters such temperature, pressure and relative humidity need to be known, but also how the sampling time, flow rate, ozone concentration and monoterpene type affects this analysis method are needed. In consideration of the difference between reactive monoterpenes and nonreactive monoterpenes, several single monoterpenes were selected and smog chamber experiments were conducted. The precision of the sampling method at various sampling times, flow rates and ozone concentrations were compared for both single monoterpenes and monoterpenes mixture. The sampling flow rate had no significant effect on this SPME sampling method. On the contrary, the GC response did have noticeable change when the sampling time and the ozone concentration were varied. A radical scavenger study was conducted and the result indicated that radical scavenger did not have a significant effect on SPME fiber or the precision and accuracy of sampling method.
Book Synopsis Solid Phase Micro-extraction (SPME) for the Determination of Volatile Chemicals in Fraser Fir (Abies Fraseri) and Red Spruce (Picea Rubens) Tissue by : Delton A. Vereen
Download or read book Solid Phase Micro-extraction (SPME) for the Determination of Volatile Chemicals in Fraser Fir (Abies Fraseri) and Red Spruce (Picea Rubens) Tissue written by Delton A. Vereen and published by . This book was released on 2000 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Analysis of Complex Volatile Organic Compound Mixtures Using Active SPME-GC-MS by : Lord Famiyeh
Download or read book Analysis of Complex Volatile Organic Compound Mixtures Using Active SPME-GC-MS written by Lord Famiyeh and published by . This book was released on 2015 with total page 53 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ultimate goal of this research is to develop an efficient, reproducible and low cost method for analysis of VOCs in complex mixtures such as those in exhaled breath and in headspace of fungi cultures. In Chapter I; analytical methods for volatile biomarkers identification is reviewed. In Chapter II, active SPME GCMS was employed to analyze VOCs in the breath of a single healthy male and a single female. The goal was to determine the extent of intra-individual variations in the VOC profiles. In Chapter III, a preliminary study was carried out in a greenhouse to determine the pathogenicity of different isolates of M. phaseolina on soybeans. This will allow, in future studies, the matching of VOC profiles of different isolates of M. phaseolina with their relative pathogenicity. This is a key step towards the development of an early warning system for the detection of pathogenic M. phaseolina fungus contaminations.
Book Synopsis Application of Non-targeted Volatile Metabolomics in Plant Pathology by : Jinyan She
Download or read book Application of Non-targeted Volatile Metabolomics in Plant Pathology written by Jinyan She and published by . This book was released on 2017 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our study focuses on the application of volatile metabolomics and chemometrics in plant pathology. Chapter one provides an overview of mass spectrometry based volatile metabolomics. The study of volatile metabolites profiles from virulent and hypovirulent strains of C. parasitica are presented in chapter two. The microbial volatile organic compounds (MVOCs) profiles were analyzed via headspace solid phase microextraction (HS-SPME) and gas chromatography (GC)-mass spectrometry (MS). The results indicate that the MVOCs from these two strains are significantly different. Furthermore, the study explored MVOCs differences associated with hypovirulence processes. The study found that both hypovirulence and aging can alter the virulent strains' MVOCs, and the process can be observed via their volatile metabolites. Chapter three describes the effects of aging, cultivation medium, and pH on fungal volatile metabolite profiles, all of which can change the strength of MVOCs emission and their composition. An acidic environment favors fungal bioactivity and therefore enhanced MVOCs emission. However, due to the inherently low MVOCs production from hypovirulent strains, the pH effect was less apparent in the hypovirulent isolates. The strength of MVOCs emission was highly correlated to the fungal expansion in virulent strains for the first 14 days. Finally, the cultivation media are critical to the fungal MVOCs production. Among the tested media, cornmeal was least favorable for MVOCs production for both strains. Chapter Four presents a study of the total constitutive phenolic content estimation and volatile organic compounds identification from four species of chestnut tree leaf tissues. Folin Ciocalteu reagent assay with UV/Vis spectrophotometry was applied to estimate the total phenolic content in leaf tissues of American chestnut (Castanea dentata), Chinese chestnut (Castanea mollissima), and their backcross breeding generations (B3F2 and B3F3). The results show that the variations among these tree species are significant (ANOVA, p
Book Synopsis Development of Portable Collection and Detection Systems for Volatile Organic Compounds by : Alexander G. Fung
Download or read book Development of Portable Collection and Detection Systems for Volatile Organic Compounds written by Alexander G. Fung and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Volatile organic compounds (VOCs) are present throughout the environment. They are emitted by all living organisms and can be used as biomarkers for health diagnostics for plants and humans. Additionally, a number of VOCs are toxic to humans and must be monitored to limit exposure and negative health effects. Different methods of collecting and detecting VOCs exist; however, with advances in microfabrication and computational power, new, improved techniques can be developed. This work presents the design and implementation of multiple devices that can be used for the collection and detection of VOCs. These devices range from integrating spirometry with chemical sensing, to developing new methods of collecting volatiles from the environment using solid phase microextraction fibers, to a wearable device that uses a micro preconcentrator to sample a person’s environmental chemical exposure. Finally, a mobile platform for a portable chemical sensor was developed and control of the peripherals was demonstrated.
Book Synopsis Determination of Volatile Organic Compounds in Air by Solid Phase Microextration by : Meng Chai
Download or read book Determination of Volatile Organic Compounds in Air by Solid Phase Microextration written by Meng Chai and published by . This book was released on 1994 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Chemotypic Variation of Biogenic Volatile Organic Compounds in Midwest Forest and Atmospheric Role of Peroxyacyl Nitrates in Southeastern U.S. by : Shino Toma
Download or read book Chemotypic Variation of Biogenic Volatile Organic Compounds in Midwest Forest and Atmospheric Role of Peroxyacyl Nitrates in Southeastern U.S. written by Shino Toma and published by . This book was released on 2017 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biogenic volatile organic compounds (VOC), including isoprene and terpenes, impact atmospheric processes such as production of tropospheric ozone, formation and growth of secondary organic aerosol (SOA), global climate change, and human health. Although estimated emission rates of total biogenic VOC exceed anthropogenic emissions, there are many challenges to direct measurements because they are very reactive with atmospheric oxidants and some are still difficult to detect by current analytical techniques. Therefore, high uncertainties lead to discrepancies between individual and total biogenic VOC budget with atmospheric oxidants and an underestimation of SOA formation. White pine (Pinus strobus) was once a dominant species in many parts of the Great Lakes region and is currently growing back. To estimate future air quality in light of Midwest forest succession, the composition of terpenes in white pine needles was analyzed over five growing seasons at the University of Michigan Biological Station and other forests in Michigan using gas chromatography with mass spectrometric detection. Early successional trees were selectively girdled in one forest in 2008, and the successional influence on total terpene concentration in this forest was observed by 2011. Terpene composition in pine needles displays chemotypic variation within forests at the molecular biology level and has the potential to affect atmospheric chemistry. Alpha-Pinene was the dominant terpene in white pine and accounted for 30-50% of all terpenes on a mole basis. However, 14% of the trees showed high levels of a single enantiomer of limonene in the same specific trees every year. The limonene contribution to hydroxyl radical reactivity was estimated to be approximately 4% higher than without consideration of chemotypic differences, which may be derived from genetic differences. Peroxyacetyl nitrate (PAN), peroxypropionyl nitrate (PPN), and peroxymethacryloyl nitrate (MPAN), photooxidation products of VOC in the presence of nitrogen oxides (NOx), were measured during the Southern Oxidation and Aerosol Study (SOAS) field campaign in Alabama in summer 2013 using GC-ECD. The measured levels were lower than in past ground measurements in the southeast, with daytime means of PAN: 169, PPN: 5, and MPAN: 9 parts per trillion volume. Higher levels were seen in air influenced by urban sources. A multiple regression analysis indicates that biogenic VOC can account for 66% of PAN formation over the campaign. MPAN, which is derived solely from isoprene, is more strongly correlated to isoprene nitrates than to its precursor methacrolein, which indicates the possibility of an unreported atmospheric mechanism for formation of MPAN. This work reports the first relationship between gas-phase MPAN and organic particles from field measurements. The highest levels of MPAN correlate well with high levels of total organic mass in particles (R2=0.455). In addition, chamber experiments of isoprene photooxidation in the presence of NOx showed a significant amount of a PAN-type compound identified as peroxyacryloyl nitrate (APAN), which is typically described as an anthropogenic product. APAN may assist in particle growth like MPAN.
Book Synopsis Analysis of Volatile Organic Compounds in the Human Breath with Micro Extraction Techniques and Continuous Monitoring of Carbon Dioxide Concentration by : Wei Ma
Download or read book Analysis of Volatile Organic Compounds in the Human Breath with Micro Extraction Techniques and Continuous Monitoring of Carbon Dioxide Concentration written by Wei Ma and published by . This book was released on 2006 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Determinations of Potential Volatile Organic Compounds in Consumer Products by Solid-phase Microextraction Coupled with GC/MS-MS. by : 劉晉廷
Download or read book Determinations of Potential Volatile Organic Compounds in Consumer Products by Solid-phase Microextraction Coupled with GC/MS-MS. written by 劉晉廷 and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
