Download or read book Application of Two Dimensional Compound Specific Carbon chlorine Isotope Analyses for Degradation Monitoring and Assessment of Organic Pollutants in Contaminated Soil and Groundwater written by and published by . This book was released on 2013 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Compound specific Stable Isotope Analysis written by Maik A Jochmann and published by Royal Society of Chemistry. This book was released on 2015-11-09 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of Compound-specific Stable Isotope Analysis (CSIA) is increasing in many areas of science and technology for source allocation, authentication, and characterization of transformation reactions. Until now, there have been no textbooks available for students with an analytical chemical background or basic introductory books emphasising the instrumentation and theory. This book is the first to focus solely on stable isotope analysis of individual compounds in sometimes complex mixtures. It acts as both a lecture companion for students and a consultant for advanced scientists in fields including forensic and environmental science. The book starts with a brief history of the field before going on to explain stable isotopes from scratch. The different ways to express isotope abundances are introduced together with isotope effects and isotopic fractionation. A detailed account of the required technical equipment and general procedures for CSIA is provided. This includes sections on derivatization and the use of microextraction techniques in GC-IRMS. The very important topic of referencing and calibration in CSIA is clearly described. This differs from approaches used in quantitative analysis and is often difficult for the newcomer to comprehend. Examples of successful applications of CSIA in food authenticity, forensics, archaeology, doping control, environmental science, and extraterrestrial materials are included. Applications in isotope data treatment and presentation are also discussed and emphasis is placed on the general conclusions that can be drawn from the uses of CSIA. Further instrumental developments in the field are highlighted and selected experiments are introduced that may act as a basis for a short practical course at graduate level.
Download or read book The Utilization of Bioremediation to Reduce Soil Contamination Problems and Solutions written by Václav Sasek and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 411 pages. Available in PDF, EPUB and Kindle. Book excerpt: Traditional reliance on chemical analysis to understand the direction and extent of treatment in a bioremediation process has been found to be inadequate. Whereas the goal of bioremediation is toxicity reduction, few direct, reliable measures of this process are as yet available. Another area of intense discussion is the assessment of market forces contributing to the acceptability of bioremediation. Finally, another important component is a series of lectures and lively exchanges devoted to practical applications of different bioremediation technologies. The range of subjects covers a wide spectrum, encompassing emerging technologies as well as actual, full-scale operations. Examples discussed include landfarming, biopiling, composting, phytoremediation and mycoremediation. Each technology is explored for its utility and capability to provide desired treatment goals. Advantages and limitations of each technology are discussed. The concept of natural attenuation is also critically evaluated since in some cases where time to remediation is not a significant factor, it may be an alternative to active bioremediation operations.
Download or read book Investigation of Stable Carbon Compound Specific Isotope Analysis to Monitor and Quantify the Biodegradation Fo Chlorinated Ethenes in Groundwater Systems written by Penny Lea Morrill and published by . This book was released on 2005 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book In Situ Remediation of Chlorinated Solvent Plumes written by Hans F. Stroo and published by Springer Science & Business Media. This book was released on 2010-09-10 with total page 807 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the late 1970s and early 1980s, our nation began to grapple with the legacy of past disposal practices for toxic chemicals. With the passage in 1980 of the Comprehensive Envir- mental Response, Compensation, and Liability Act (CERCLA), commonly known as Sup- fund, it became the law of the land to remediate these sites. The U. S. Department of Defense (DoD), the nation’s largest industrial organization, also recognized that it too had a legacy of contaminated sites. Historic operations at Army, Navy, Air Force, and Marine Corps facilities, ranges, manufacturing sites, shipyards, and depots had resulted in widespread contamination of soil, groundwater, and sediment. While Superfund began in 1980 to focus on remediation of heavily contaminated sites largely abandoned or neglected by the private sector, the DoD had already initiated its Installation Restoration Program in the mid-1970s. In 1984, the DoD began the Defense Environmental Restoration Program (DERP) for contaminated site assessment and remediation. Two years later, the U. S. Congress codified the DERP and directed the Secretary of Defense to carry out a concurrent program of research, development, and demonstration of innovative remediation technologies. As chronicled in the 1994 National Research Council report, “Ranking Hazardous-Waste Sites for Remedial Action,” our early estimates on the cost and suitability of existing techn- ogies for cleaning up contaminated sites were wildly optimistic. Original estimates, in 1980, projected an average Superfund cleanup cost of a mere $3.
Download or read book Compound Specific Stable Isotope Analysis written by Safdar Bashir and published by Sudwestdeutscher Verlag Fur Hochschulschriften AG. This book was released on 2014-08-12 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the most promising tools for both characterizing contaminant sources and monitoring in situ degradation of organic contaminants in aquifers is compound-specific stable isotope analysis, in which the stable isotope ratios of one or more elements in a given compound are measured in order to investigate the transformation processes at work.The objective of this book was to validate the application of carbon-compound specific stable isotope analysis (CSIA) and enantiomer specific stable isotope analysis (ESIA) to characterize biotic and abiotic transformation of Hexachlorocyclohexane (HCH) in situ. Additionally, to prove that CSIA in combination with enantiomer-selective degradation of -HCH can be applied as an effective and reliable tool for monitoring natural attenuation of HCH. The variability in enrichment factors observed for enantiomers during biotic investigation showed the preferential reactivity of enzymes for one enantiomer over the other which is not observed in abiotic studies. Thus CSIA combined with ESIA and enantiomer fractions (EF) can help to distinguish biotic and abiotic reactions taking place in situ."
Download or read book Use of Stable Isotopoe Analyses to Assess Natural Attenuation of Chlorinated Ethenes in Groundwater written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Chlorinated ethenes are among the most frequently detected groundwater contaminants in industrially developed countries. Although their degradation pathways have been understood, assessing the progress of natural attenuation of chlorinated ethenes still remains a challenge. This thesis explored the possibilities and limits of the use of compound-specific stable isotope analysis as a field investigation tool to document and to quantify the progress of natural attenuation of chlorinated ethenes. The thesis focused particularly on the fate of reductive dechlorination intermediates such as cis-dichloroethene (cDCE) and vinyl chloride (VC) as the success of natural attenuation of chlorinated ethenes depends principally on the fate of these compounds. Two field investigations were carried out to demonstrate the use of stable isotope analysis to characterize the progress of natural attenuation of chlorinated ethenes. One site was characterized as a complex hydrological and geochemical system at the groundwater-surface water interface where a tetrachloroethene- (PCE) plume discharged through the streambed. Another site was located under relatively stable hydrological conditions and characterized by a 2-km long plume of chlorinated ethenes. Laboratory studies evaluated the use of combined carbon and chlorine isotope analysis to distinguish different degradation pathways of cDCE and VC, and the same approach was employed at a field site to determine the fate of cDCE. Numerical studies evaluated the field applicability of isotope-based quantification, according to the Rayleigh isotope fractionation model, to estimate the extent of degradation and the first-order reaction rate under various flow conditions. In addition, a scheme to quantify the reductive dechlorination rates of chlorinated ethenes based on field concentration and isotope data at one of the field sites was proposed and evaluated with a series of 3D analytical solutions to accommodate sequential reactions. The stu.
Download or read book Analysis of Carbon Isotopes Determination of Ground water Age and Estimated Characteristics of the Contaminant Source at Two Fuel spill Plumes Western Cape Cod Massachusetts 1996 written by Jennifer Savoie and published by . This book was released on 1999 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Groundwater Quality written by Steven F. Thornton and published by . This book was released on 2002 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Index Medicus written by and published by . This book was released on 2004 with total page 2292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vols. for 1963- include as pt. 2 of the Jan. issue: Medical subject headings.
Download or read book Use of compound specific stable isotopes of carbon and chlorine for source tracking and assessments of biodegradation potential in a chlorinated solvent plume in Fort Worth Texas written by Christopher Lee Braun and published by . This book was released on 2005 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monitored Natural Attenuation of Inorganic Contaminants in Ground Water written by and published by . This book was released on 2007 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: V.3 ... consists of individual chapters that describe 1) the conceptual background for radionuclides, including tritium, radon, strontium, technetium, uranium, iodine, radium, thorium, cesium, plutonium-americium and 2) data requirements to be met during site characterization.
Download or read book Environmental Isotopes in Biodegradation and Bioremediation written by C. Marjorie Aelion and published by CRC Press. This book was released on 2009-11-04 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: Enhanced analytical capabilities and separation techniques, improved detection limits, and accessibility of instrumentation have led to massive strides in the use of isotopes to assess microbial processes in surface and subsurface sediments. Considering the rapid growth of research and commercial interest in stable isotope and radioisotope applicat
Download or read book The Geochemistry of Stable Chlorine and Bromine Isotopes written by Hans Eggenkamp and published by Springer. This book was released on 2014-08-25 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides detailed information on the history, analysis and applications of chlorine and bromine isotope geochemistry. Chlorine and bromine are geochemically unique as they prefer to exist as single charged negative ions. For this reason isotope fractionation reflects mostly processes that are not related to changes in the redox state and this fractionation is generally modest. The book will describe the processes that are most easily detected using these isotopes. Also isotope variations, and processes that cause them, measured in oxidised species such as perchlorates and in organic molecules will be described in this book.
Download or read book Compound Specific Isotope Analysis 13C 37Cl 2H to Trace Induced Attenuation of Chlorinated Organic Contaminants in Groundwater written by Carme Audí Miró and published by . This book was released on 2014 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: El chloroform (CF), el tetracloroetè (PCE) i el tricloretè (TCE) són hidrocarburs clor-alifàtics densos usats extensament com a solvents industrials. Aquests compostos s'han alliberat al medi degut a un tractament inadequat dels seus residus. En aquesta tesi, l'efecte d'una barrera permeable reactiva de ferro zero valent (BPR-FZV) instal·lada en un emplaçament contaminat majoritàriament amb PCE, TCE i cis-dicloretè (cis-DCE, subproducte de TCE) ha estat avaluada. A més a més, s'ha proposat i desenvolupat una nova estratègia per a degradar el CF, el qual és un compost recalcitrant, consistent en la inducció de la hidròlisi alcalina del CF mitjançant residus de construcció basats en formigó. L'ànàlisi isotòpic de compost específic (AICE) és una eina valuosa per al monitoreig d'un sistema de tractament medi ambiental, basant-se en el fraccionament isotòpic d'un element durant les reaccions de transformació. L'objectiu general d'aquesta tesi és l'ús de l'anàlisi isotòpic de compost específic de 13C, 37Cl i 2H com una eina per a controlar els dos processos d'atenuació 1) la degradació dels eten-clorats mitjançant una BPR-FZV instal·lada en el camp; i, 2) la nova tècnica de remediació de CF proposada basada en l'ús de residus reciclats de la construcció per tal d'induir la hidròlisi alcalina del CF. En general, mitjançant la combinació dels isòtops de C, Cl i H, aquesta tesi aporta noves eines per discriminar la degradació dels compostos organoclorats d'estudi mitjançant FZV, respecte la biodegradació en el camp, així com també per a identificar fonts de contaminació d'origen industrial o de productes formats, entre d'altres aportacions. A més a més, el nou mètode proposat per a degradar el CF basat en la seva hidròlisi alcalina mitjançant l'ús de residus de construcció reciclats ha demostrat ser eficient en la degradació d'aquest contaminant, així com també, mitjançant l'ús de isòtops de carboni, ha demostrat funcionar en experiments pilot monitorejats a escala de camp.
Download or read book Investigating Mechanisms of Chlorinated Ethane Biotransformation Using Compound Specific Carbon Isotope Analysis written by Sarah Kathleen Hirschorn and published by . This book was released on 2007 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stable carbon isotope fractionation during biotransformation of the chlorinated ethanes 1,2-dichloroethane (1,2-DCA), 1,1,1-trichloroethane (1,1,1-TCA) and 1,1-dichloroethane (1,1-DCA) was investigated. Isotopic fractionation during aerobic 1,2-DCA biotransformation in microcosms, enrichment cultures and pure microbial cultures was measured and was found to be pathway dependent. Biodegradation of 1,2-DCA under aerobic conditions produced a consistent bimodal distribution of enrichment factors (s) with one mean c centered on --3.9 +/- 0.6 and the other on --29.2 +/- 1.9. Reevaluation of epsilon in terms of kinetic isotope effects 12k/ 13k, gave values of 12k/13k = 1.01 and 1.06, which are typical of oxidation and hydrolytic dehalogenation (S N2) reactions, respectively. The relationship between degradation pathway and measured carbon isotope fractionation was applied to constrain the degradation pathway of 1,2-DCA in a microbial enrichment culture capable of degrading 1,2-DCA under both O2 and NO3-reducing conditions, but where the degradation pathway was previously uncharacterized. delta 13C values indicated biodegradation in the enrichment culture under both O2 and NO3-reducing conditions likely proceeded via a hydrolytic dehalogenase enzyme. Stable carbon isotope analysis during biotransformation of other chlorinated ethanes was then investigated. Isotopic enrichment factors of -1.9 and -10.4 were measured during reductive dechlorination of 1,1,1-trichloroethane (1,1,1-TCA) and 1,1-dichloroethane (1,1-DCA), respectively. These are the first reported isotopic enrichment factors for microbial biotransformation of these compounds, which can now potentially be applied to investigate and quantify biodegradation of 1,1,1-TCA and 1,1-DCA in the field. Stable carbon isotope analysis was used to provide a conservative estimate of the extent of 1,2-DCA and trichloroethene (TCE) biodegradation in a biostimulation field study. Isotope analysis was able to confirm that 1,2-DCA degradation, rather than degradation of vinyl chloride, was the primary mechanism of ethene production at the site. This thesis not only advances the application of compound specific carbon isotope fractionation to identify and quantify biodegradation of chlorinated ethanes in groundwater, but in particular progresses our understanding of the relationship between the enzymatic mechanisms of contaminant degradation and isotopic fractionation, and the ability to use that knowledge to predict degradation mechanisms for previously unconstrained pathways of contaminant remediation.
Download or read book Environmental Protection Research Catalog Indexes written by Smithsonian Science Information Exchange and published by . This book was released on 1972 with total page 1478 pages. Available in PDF, EPUB and Kindle. Book excerpt:
