Download or read book Investigations Into the Extraction and the Determination of Polycyclic Aromatic Hydrocarbons PAHs from Water by Solid phase Extraction and Capillary Gas Chromatography Mass Spectrometry written by Mohamed Elrutb and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigations Into the Extraction and the Determination of Polycyclic Aromatic Hydrocarbons PAHs from Water by Solid phase Extraction and Capillary Gas Chromatography written by Elrutb, Mohamed and published by 1993.. This book was released on 1993 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Toxicological Profile for Polycyclic Aromatic Hydrocarbons written by and published by . This book was released on 1995 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Application of Relative Response Factors in Solid Phase Micro Extraction GC MS for the Determination of Polycyclic Aromatic Hydrocarbons in Water written by Tomi Schebywolok and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Solid-phase microextraction (SPME) coupled with gas chromatography/mass spectrometry (GC/MS) is routinely used to analyze polycyclic aromatic hydrocarbons (PAHs) in water. A common SPME-GC/MS approach quantifies target analytes using isotopically labeled standards (IISs); one IIS is needed for each target analyte. This approach is challenging, even prohibitive since IISs are often expensive; moreover, they are generally not available for each analyte of interest. This study developed a novel SPME-GC/MS approach for the quantification of PAHs in water. The new method, which employs only a small number of IISs, uses relative response factor (RRF) (i.e., analyte corresponding to IIS) to quantify PAHs in water. Possible matrix dependency of RRFs values was examined using water that was modified concerning different physical-chemical characteristics (i.e., ionic strength, pH, suspended solids, humic acid, and biological organic carbon represented by hemoglobin). The results revealed that RRFs are not noticeably affected by changing ionic strength and pH; the other three parameters did affect the RRFs. However, the results also showed that the effect is minimal when the solution is dilute (i.e., low concentrations of suspended solids, humic acid or hemoglobin). Relatively stable RRFs for dilute water solutions indicates that this approach can be used for routine quantification of water that does not contain prohibitive amounts of suspended solids, humic acid, and biological organic matter. The developed method was employed to quantify trace levels of PAHs in three different types of water, namely river water, well water, and bottled water. PAH levels in every kind of water were less than 100 ng/L level (i.e., 0.1 ppb). Analyses of spiked water samples containing 2 ng PAHs revealed correlations between calculated RRFs and the physical-chemical properties of the PAHs investigated (i.e., vapor pressure, boiling point, octanol/water partition coefficient, octanol/air partition coefficient, GC retention time). This implies that RRFs for PAHs not examined in this study can be predicted. Overall, the results presented herein constitute a meaningful contribution to the development of SPME-GC/MS methods for quantitative analysis of PAHs and other chemicals in dilute aqueous solutions. Moreover, the development of methods that alleviate the need for IISs corresponding to each target analyte.
Download or read book Sample Preparation Techniques in Analytical Chemistry written by Somenath Mitra and published by John Wiley & Sons. This book was released on 2004-04-07 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance of accurate sample preparation techniques cannot be overstated--meticulous sample preparation is essential. Often overlooked, it is the midway point where the analytes from the sample matrix are transformed so they are suitable for analysis. Even the best analytical techniques cannot rectify problems generated by sloppy sample pretreatment. Devoted entirely to teaching and reinforcing these necessary pretreatment steps, Sample Preparation Techniques in Analytical Chemistry addresses diverse aspects of this important measurement step. These include: * State-of-the-art extraction techniques for organic and inorganic analytes * Sample preparation in biological measurements * Sample pretreatment in microscopy * Surface enhancement as a sample preparation tool in Raman and IR spectroscopy * Sample concentration and clean-up methods * Quality control steps Designed to serve as a text in an undergraduate or graduate level curriculum, Sample Preparation Techniques in Analytical Chemistry also provides an invaluable reference tool for analytical chemists in the chemical, biological, pharmaceutical, environmental, and materials sciences.
Download or read book Report on the Inter laboratory Comparison Organised by the European Union Reference Laboratory for Polycyclic Aromatic Hydrocarbons for the Validation of a Method for Quantifying the Four EU Marker PAHs in Food written by and published by . This book was released on 2012 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Masters Theses in the Pure and Applied Sciences written by Wade H. Shafer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: Masters Theses in the Pure and Applied Sciences was first conceived, published, and disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS)* at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dis semination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all concerned if the printing and distribution of the volumes were handled by an international publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Corporation of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 38 (thesis year 1993) a total of 13,787 thesis titles from 22 Canadian and 164 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this impor tant annual reference work. While Volume 38 reports theses submitted in 1993, on occasion, certain uni versities do report theses submitted in previous years but not reported at the time.
Download or read book Investigations Into the Determination of Polycyclic Aromatic Hydrocarbons PAHs and Polychlorinated Biphenyls PCBs by Capillary Gas Chromatography written by Xing-Fang Li and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Factors involved in the determination of PAHs (16 priority PAHs as an example) and PCBs (10 PCB congeners, representing 10 isomeric groups) by capillary gas chromatography coupled with mass spectrometry (GC/MS, for PAHs) and electron capture detection (GC/ECD , for PCBs) were studied, with emphasis on the effect of solvent. Having various volatilities and different polarities, solvent studied included dichloromethane, acetonitrile, hexan e, cyclohexane, isooctane, octane, nonane, dodecane, benzene, toluene, p-xylene, o-xylene, and mesitylene. Temperatures of the capillary column, the injection port, the GC/MS interface, the flow rates of carrier gas and make-up gas, and the injection volume were optimized by one factor at a time method or simplex optimization method. Under the optimized conditions, both peak height and peak area of 16 PAHs, especially the late-eluting PAHs, were significantly enhanced (1 to 500 times) by using relatively higher boiling point solvents such as p-xylene and nonane, compared with commonly used solvents like benzene and isooctane. With the improved sensitivity, detection limits of between 4.4 pg for naphthalene and 30.8 pg for benzo[g,h,i]perylene were obtained when p-xylene was used as an injection solvent. Effect of solvent on peak shape and peak intensity were found to be greatly dependent on temperature parameters, especially the initial temperature of the capillary column. The relationship between initial temperature and shape of peaks from 16 PAHs and 10 PCBs were studied and compared when toluene, p-xylene, isooctane, and nonane were used as injection solvents. If a too low initial temperature was used, fronting or split of peaks was observed. On the other hand, peak tailing occurred at a too high initial column temperature. The optimum initial temperature, at which both peak fronting and tailing were avoided and symmetrical peaks were obtained, depended on both solvents and the stationary phase of the column used. On a methyl silicone column, the alkane solvents provided wider optimum ranges of initial temperature than aromatic solvents did, for achieving well-shaped symmetrical GC peaks. On a 5% diphenyl: 1% vinyl: 94% dimethyl polysiloxane column, when the aromatic solvents were used, the optimum initial temperature ranges for solutes to form symmetrical peaks were improved to a similar degree as those when the alkanes were used as injection solvents. A mechanism, based on the properties of and possible interactions among the analyte, the injection solvent, and the stationary phase of the capillary column, was proposed to explain these observations. The effect of initial temperature on peak height and peak area of the 16 PAHs and the 10 PCBs was also studied. The optimum initial temperature was found to be dependent on the physical properties of the solvent used and the amount of the solvent injected. Generally, from the boiling point of the solvent to 10 0C above its boiling point was an optimum range of initial temperature at which cthe highest peak height and peak area were obtained.
Download or read book Sample Preparation by Small Solid phase Extraction Membrane for Determination of Polycyclic Aromatic Hydrocarbons in Water written by Suchada Chimam and published by . This book was released on 1997 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: A small disk extraction method (I.D. 13 mm) was developed for determination of 16 PAHs, EPA priority pollutants, from water samples. It was cost-effective, time-saving, and non-toxic method. Factors affecting the recoveries of PAHs such as solubilizer concentration, volume of eluting solvent, elution time, and breakthrough volume were studied. The presence of 0.30 mM Briji-35 was most appropriate for the enrichment of PAHs on C18 disk. Elution with 0.50 mL acetonitrile gave the high recoveries and the recoveries did not change significantly after 15 min of elution. Optimum solution volume was 100 mL. The method detection limit was found to range from less than 0.01 ppb to 0.20 ppb. The recoveries varied from 72.88 to 117.12% with percent relative standard deviation (% R.S.D.) between 1.96 and 2.82% except Anthracene was 55.09% recovery. Percent error of this method were in the range of 0.65-9.58%. Moreover, this extraction method was applied to determine PAHs in real water samples.
Download or read book Polycyclic Aromatic Hydrocarbons in Water Sys written by David J. Futoma and published by Springer. This book was released on 1981-11-05 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Opisane so spektroskopske in kromatografske analize PAH v vodi, njihova topnost, vzorčevanje in predhodno koncentriranje.
Download or read book Novel Improvements on the Analytical Chemistry of Polycyclic Aromatic Hydrocarbons and Their Metabolites written by Wang Huiyong and published by . This book was released on 2010 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycyclic aromatic hydrocarbons (PAH) are important environmental pollutants originating from a wide variety of natural and anthropogenic sources. Because many of them are highly suspect as etiological agents in human cancer, chemical analysis of PAH is of great environmental and toxicological importance. Current methodology for PAH follows the classical pattern of sample preparation and chromatographic analysis. Sample preparation pre-concentrates PAH, simplifies matrix composition, and facilitates analytical resolution in the chromatographic column. Among the several approaches that exist to pre-concentrate PAH from water samples, the Environmental Protection Agency (EPA) recommends the use of solid-phase extraction (SPE). High-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) are the basis for standard PAH identification and determination. Ultraviolet (UV) absorption and room temperature fluorescence detection are both widely used in HPLC, but the specificity of these detectors is modest. Since PAH identification is solely based on retention times, unambiguous PAH identification requires complete chromatographic resolution of sample components. When HPLC is applied to "unfamiliar" samples, the EPA recommends that a supporting analytical technique such as GC-MS be applied to verify compound identification and to check peak-purity HPLC fractions. Independent of the volume of extracted water, the approximate time required to separate and determine the sixteen "priority pollutants" (EPA-PAH) via HPLC is approximately 60min. If additional GC-MS analysis is required for unambiguous PAH determination, the total analysis time will reach 2-3 hours per sample. If the concentrations of target species are found to lie outside the detector's response range, the sample must be diluted and the process repeated. These are important considerations when routine analysis of numerous samples is contemplated. Parent PAH are relatively inert and need metabolic activation to express their carcinogenicity. By virtue of the rich heterogeneous distribution of metabolic products they produce, PAH provide a full spectrum of the complexity associated with understanding the initial phase of carcinogenesis. PAH metabolites include a variety of products such as expoxides, hydroxyl aromatics, quinines, dihydrodiols, dioepoxides, tetrols and water soluble conjugates. During the past decades tremendous efforts have been made to develop bio-analytical techniques that possess the selectivity and sensitivity for the problem at hand. Depending on the complexity of the sample and the relative concentrations of the targeted metabolites, a combination of sample preparation techniques is often necessary to reach the limits of detection of the instrumental method of analysis. The numerous preparation steps open ample opportunity to metabolite loss and collection of inaccurate data. Separation of metabolites has been accomplished via HPLC, capillary electrophoresis (CE) and GC-MS. Unfortunately, the existence of chemically related metabolic products with virtually identical fragmentation patterns often challenges the specificity of these techniques. This dissertation presents significant improvements in various fronts. Its first original component--which we have named solid-phase nano-extraction (SPNE)--deals with the use of gold nanoparticles (Au NPs) as extracting material for PAH. The advantages of SPNE are demonstrated for the analysis of PAH in water samples via both HPLC and Laser-Excited Time-Resolved Shpol'skii Spectroscopy (LETRSS). The same concept is then extended to the analysis of monohydroxy-PAH in urine samples via SPE- HPLC and In-Capillary SPNE-CE. The second original component of this dissertation describes the application of Shpol'skii Spectroscopy to the analysis of polar PAH metabolites. The outstanding selectivity and sensitivity for the direct analysis of PAH at trace concentration levels has made Shpol'skii spectroscopy a leading technique in environmental analysis. Unfortunately, the requirement of a specific guest-host combination--typically a non-polar PAH dissolved in an n-alkane-- has hindered its widespread application to the field of analytical chemistry. This dissertation takes the first steps in removing this limitation demonstrating its feasibility for the analysis of polar benzopyrene metabolites in alcohol matrixes.
Download or read book Handbook of Solid Phase Microextraction written by Janusz Pawliszyn and published by Elsevier. This book was released on 2011-12-01 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt: The relatively new technique of solid phase microextraction (SPME) is an important tool to prepare samples both in the lab and on-site. SPME is a "green" technology because it eliminates organic solvents from analytical laboratory and can be used in environmental, food and fragrance, and forensic and drug analysis. This handbook offers a thorough background of the theory and practical implementation of SPME. SPME protocols are presented outlining each stage of the method and providing useful tips and potential pitfalls. In addition, devices and fiber coatings, automated SPME systems, SPME method development, and In Vivo applications are discussed. This handbook is essential for its discussion of the latest SPME developments as well as its in depth information on the history, theory, and practical application of the method. Practical application of Solid Phase Microextraction methods including detailed steps Provides history of extraction methods to better understand the process Suitable for all levels, from beginning student to experienced practitioner
Download or read book Determination of Semivolatile Organic Compounds and Polycyclic Aromatic Hydrocarbons in Solids by Gas Chromatography mass Spectrometry written by and published by . This book was released on 2006 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Application of Solid Phase Extraction and Gas Chromatograph mass Spectrometry for Trace Determination of Polycyclic Aromatic Hydrocarbons from Atmospheric Wet and Dry Deposition Samples written by Pakorn Varanusupakul and published by . This book was released on 2000 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hydrocarbon Pollution and its Effect on the Environment written by Muharrem Ince and published by BoD – Books on Demand. This book was released on 2019-12-04 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers hydrocarbon pollution, measurement techniques for hydrocarbons, risk assessment, and environmental impact. This comprehensive book takes a broad view of the subject and integrates a wide variety of approaches. This book attempts to address the needs of graduate and postgraduate students and other professionals or readers interested in food, soil, water, and air pollution. The aim of this book is to explain and clarify important studies, and compare and develop the new and groundbreaking measurement techniques. Written by leading experts in their respective areas, the book is highly recommended to professionals interested in environmental and human health because it provides specific and comprehensive examples.
Download or read book Cyclic Hydrocarbons Advances in Research and Application 2012 Edition written by and published by ScholarlyEditions. This book was released on 2012-12-26 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cyclic Hydrocarbons—Advances in Research and Application: 2012 Edition is a ScholarlyBrief™ that delivers timely, authoritative, comprehensive, and specialized information about Cyclic Hydrocarbons in a concise format. The editors have built Cyclic Hydrocarbons—Advances in Research and Application: 2012 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Cyclic Hydrocarbons in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Cyclic Hydrocarbons—Advances in Research and Application: 2012 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Methods for the Determination of Organic Compounds in Drinking Water written by and published by . This book was released on 1995 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt:
