Download or read book Determination of Nitroaromatic Nitramine and Nitrate Ester Explosives in Water Using SPE and GC ECD Comparison with HPLC written by Marianne E. Walsh and published by . This book was released on 1998 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analytical method for the determination of nitroaromatic, nitramine, and nitrate ester explosives and Co-contaminants in water was developed based on SPE (solid-phase extraction) and GC-ECD (gas chromatograph-electron capture detector). Water samples are preconcentrated using either cartridge or membrane SPE followed by elution with acetonitrile. The acetonitrile extract is compatible with both liquid and gas chromatography, thereby allowing direct comparison of concentration estimates obtained by different methods of determination. Quantitative GC analyses were obtained by using deactivated direct-injection-port liners, short wide-bore capillary columns. and high linear carrier gas velocities. Recoveries from spiked samples were 90% or greater for each of the nitroaromatics and nitrate esters, and greater than 70% for nitramines and amino-nitrotoluenes. Estimates of analyte concentrations in well-water extracts from military sites in the United States and Canada analyzed by GC-ECD and the standard HPLC (high performance liquid chromatography) method showed good agreement for the analytes most frequently detected (HMX octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, RDX hexahydro-1,3,5-trinitro-1,3,5-triazine, TNT 2,4,6-trinitrotoluene, and TNB 1,3,5-trinitrobenzene). The GC method provides lower method detection limits for most analytes than HPLC, but accurate calibration is more difficult. The ultraviolet (UV) detector used for the HPLC analysis has much greater linear range than the ECD used for GC analysis. In addition. the GC instrumentation requires more care than the LC. Specifically the injection port liner must be changed frequently to maintain accurate determination of the nitramines. Because the sample preparation technique yields extracts that are compatible with both GC and HPLC analysis, confirmation of analyte presence can be obtained based on different physical properties.

Download or read book Determination of Nitroaromatic Nitramine and Nitrate Ester Explosives in Water Using SPE and GC ECD Comparison with HPLC written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analytical method for the determination of nitroaromatic, nitramine, and nitrate ester explosives and Co-contaminants in water was developed based on SPE (solid-phase extraction) and GC-ECD (gas chromatograph-electron capture detector). Water samples are preconcentrated using either cartridge or membrane SPE followed by elution with acetonitrile. The acetonitrile extract is compatible with both liquid and gas chromatography, thereby allowing direct comparison of concentration estimates obtained by different methods of determination. Quantitative GC analyses were obtained by using deactivated direct-injection-port liners, short wide-bore capillary columns. and high linear carrier gas velocities. Recoveries from spiked samples were 90% or greater for each of the nitroaromatics and nitrate esters, and greater than 70% for nitramines and amino-nitrotoluenes. Estimates of analyte concentrations in well-water extracts from military sites in the United States and Canada analyzed by GC-ECD and the standard HPLC (high performance liquid chromatography) method showed good agreement for the analytes most frequently detected (HMX octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, RDX hexahydro-1,3,5-trinitro-1,3,5-triazine, TNT 2,4,6-trinitrotoluene, and TNB 1,3,5-trinitrobenzene). The GC method provides lower method detection limits for most analytes than HPLC, but accurate calibration is more difficult. The ultraviolet (UV) detector used for the HPLC analysis has much greater linear range than the ECD used for GC analysis. In addition. the GC instrumentation requires more care than the LC. Specifically the injection port liner must be changed frequently to maintain accurate determination of the nitramines. Because the sample preparation technique yields extracts that are compatible with both GC and HPLC analysis, confirmation of analyte presence can be obtained based on different physical properties.

Download or read book Determination of Nitroaromatic Nitramine and Nitrate Ester Explosives in Soils Using GC ECD written by Marianne E. Walsh and published by . This book was released on 1999 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analytical Separation Science 5 Volume Set written by Jared Anderson and published by John Wiley & Sons. This book was released on 2016-02-29 with total page 2148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Endlich ein Forschungsleitfaden für Wissenschaftler des Fachgebiets, die neue Methoden entwickeln oder einsetzen. Dieses Handbuch umfasst fünf thematische Bände und bietet damit einen umfassenden Überblick über das Fachgebiet. Erläutert werden Grundlagen, die Methodenentwicklung und hochkarätige Anwendungen für alle wichtigen Analyseverfahren, darunter chromatische Verfahren, Techniken in den Bereichen Elektromigration und Membranen. Dieses Referenzwerk umfasst ein breites Spektrum und legt den Schwerpunkt auf Entwicklungen für die Zukunft. Damit ist es ein Muss für Forscher und eine wertvolle Wissensquelle für Studenten im Hauptstudium und Studienabsolventen.

Download or read book Field Gas Chromatography thermionic Detector System for On site Determination of Explosives in Soils written by Alan Dole Hewitt and published by . This book was released on 2001 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: On-site determination of nitroaromatic, nitramine, and nitrate ester explosives compounds in soils was performed using a field-portable gas chromatograph (GC)equipped with a thermionic ionization detector (TID)selective for compounds with nitro functional groups. Soil samples were extracted with acetone. A 1 microliter volume of the filtered soil extract was manually injected into the GC, allowing for the rapid qualification and quantification of the suite of explosives that often coexist in soils at military training facilities and other defense-related sites. Good agreement was established for the concentrations of several explosives analytes when this method of analysis was compared to either high-performance liquid chromatography (Method 8330)or GC electron capture (Method 8095)analysis. Comparisons were performed for sample extracts and for soil subsample replicates distributed for on-site preparation and analysis during a field verification test performed under the auspices of the U.S. Environmental Protection Agency's Environmental Technology Verification (ETV)Program.

Download or read book Determination of Nitroaromatic Nitramine and Nitrate Ester Explosives in Soils Using GC ECD written by Marianne E. Walsh and published by . This book was released on 1999 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitroaromatic, nitramine, and nitrate ester explosives are analytes of interest for hazardous waste site characterization and land mine detection. Traditionally determined by high-performance liquid chromatography (HPLC), these thermally labile analytes may be determined by gas chromatography (GC) by using direct injection into a deactivated liner and a short (6-m) wide-bore capillary column. Gas chromatography-electron capture detector (GC-ECD) and HPLC-ultraviolet (UV) concentration estimates of these compounds in field-contaminated soils from hazardous waste sites were compared, and excellent correlation (r > 0.97) was found between the two methods of analysis for the compounds most frequently detected: 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), 2,4-dinitrotoluene (2,4-DNT), 1,3-dinitrobenzene (1,3-DNB), 1,3,5-trinitrobenzene (TNB), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). GC-ECD method detection limits (MDL) were about 1 micrograms/kg for the di- and trinitroaromatics, about 10 micrograms/kg for the mononitroaromatics, 3 micrograms/kg for RDX, 25 micrograms/kg for HMX, and between 10 and 40 micrograms/kg for the nitrate esters (NG and PETN).

Download or read book Determination of Nitroaromatic Nitramine and Nitrate Ester Explosives in Soil Using GC ECD written by and published by . This book was released on 1999 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitroaromatic, nitramine, and nitrate ester explosives are analytes of interest for hazardous waste site characterization and land mine detection. Traditionally determined by high-performance liquid chromatography (HPLC), these thermally labile analytes may be determined by gas chromatography (GC) by using direct injection into a deactivated liner and a short (6-m) wide-bore capillary column. Gas chromatography-electron capture detector (GC-ECD) and HPLC-ultraviolet (UV) concentration estimates of these compounds in field-contaminated soils from hazardous waste sites were compared, and excellent correlation (r> 0.97) was found between the two methods of analysis for the compounds most frequently detected: 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), 2,4-dinitrotoluene (2,4-DNT), 1,3-dinitrobenzene (1,3-DNB), 1,3,5-trinitrobenzene (TNB), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). GC-ECD method detection limits (MDL) were about 1 micrograms/kg for the di- and trinitroaromatics, about 10 micrograms/kg for the mononitroaromatics, 3 micrograms/kg for RDX, 25 micrograms/kg for HMX, and between 10 and 40 micrograms/kg for the nitrate esters (NG and PETN).

Download or read book On site Method for Measuring Nitroaromatic and Nitramine Explosives in Soil and Groundwater Using GC NPD written by Alan Dole Hewitt and published by . This book was released on 1999 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Highly Sensitive Screening Method for Nitroaromatic Nitramine and Nitrate Ester Explosives by High Performance Liquid Chromatography Atmospheric Pressure Ionization Mass Spectrometry HPLC API MS in Forensic Applications written by X. Xu and published by . This book was released on 2004 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: A highly sensitive screening method based on high performance liquid chromatography atmospheric pressure ionization mass spectrometry (HPLC-API-MS) has been developed for the analysis of 21 nitroaromatic, nitramine and nitrate ester explosives, which include the explosives most commonly encountered in forensic science. Two atmospheric pressure ionization (API) methods, atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI), and various experimental conditions have been applied to allow for the detection of all 21 explosive compounds. The limit of detection (LOD) in the full-scan mode has been found to be 0.012-1.2 ng on column for the screening of most explosives investigated. For nitrobenzene, an LOD of 10 ng was found with the APCI method in the negative mode. Although the detection of nitrobenzene, 2-, 3-, and 4-nitrotoluene is hindered by the difficult ionization of these compounds, we have found that by forming an adduct with glycine, LOD values in the range of 3-16 ng on column can be achieved. Compared with previous screening methods with thermospray ionization, the API method has distinct advantages, including simplicity and stability of the method applied, an extended screening range and a low detection limit for the explosives studied.

Download or read book Evaluation of Pre extraction Analytical Holding Times for Nitroaromatic and Nitramine Explosives in Water written by Clarence L. Grant and published by . This book was released on 1993 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Separation and Quantitation of Nitrated Explosives Using Thin layer Chromatography and Charge coupled Device Camera Imaging written by Melissa Sue Meaney and published by . This book was released on 2007 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book On Site Method for Measuring Nitroaromatic and Nitramine Explosives in Soil and Groundwater Using GC NPD Feasibility Study written by and published by . This book was released on 1999 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: An on-site method has been developed for estimating concentrations of TNT, RDX, 2,4-DNT, and the two most commonly encountered environmental transformation products of TNT, 2-amino-4,6-dinitrotoluene and 4-amino-2,6-dinitrotoluene, in soil and groundwater using gas chromatography and the nitrogen-phosphorus detector (NPD). Soil samples (20 g) are extracted by shaking with 20 mL of acetone, and extracts are filtered through a Millex SR (0.5-micrometers) filter. Groundwater samples (1 L) were passed through SDB-RPS extraction disks that were subsequently extracted with 5 mL of acetone. A 1-micro-L volume of a soil or water extract is manually injected into a field-transportable gas chromatograph equipped with a NPD and a heated injection port. Separations are conducted on a Restek Crossbond 100% dimethyl polysiloxane column, 6 m x 0.53-mm i.d., 1.5 mm, using nitrogen carrier gas at 9.5 mL/min. Retention times range from 3.0 min. for 2,4-dinitrotoluene (2,4-DNT) to 5.6 min. for 2-amino-4,6-dinitrotoluene. Method detection limits were less than 0.16 mg/kg for soil and less than 1.0 microgram/L for groundwater. One of the major advantages of this method, over currently available colorimetric and enzyme immunoassay on-site methods, is the ability to quantify individual target analytes that often coexist in soils and groundwater contaminated with explosive residues. This method will be particularly useful at military antitank firing ranges where it is necessary to quantify residual concentrations of RDX in the presence of high concentrations of HMX, and when the transformation products of TNT need to be identified.

Download or read book The Analysis of Explosives written by Jehuda Yinon and published by Elsevier. This book was released on 2013-10-22 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Analysis of Explosives surveys the principles of the various analytical methods, describes how these methods are used for the analysis of explosives, and reviews the major analytical work carried out in this field. Organized into 15 chapters, this book begins with the classification of explosives. Subsequent chapters discuss the different methods for the analysis of explosives. The detection and identification of explosive residues and hidden explosives are also explained. This monograph will be useful as a reference book for chemists in analytical and forensic laboratories, as well as a textbook for graduate students in analytical chemistry and forensic sciences.

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 Modern Methods and Applications in Analysis of Explosives written by Jehuda Yinon and published by John Wiley & Sons. This book was released on 1996-08-06 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: An up-to-date handbook, with the latest advances including all the various methods and techniques for analyzing explosives. Explosive compounds and mixtures, residues--their recovery and clean-up procedures--chromatography, polarography, spectroscopy, environmental analysis and mass spectroscopy are among the topics covered.

Download or read book Novel Approaches for Bioremediation of Organic Pollution written by Raffi Fass and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the 42nd OHOLO Conference held in Eilat, Israel, May 3-7, 1998

Download or read book Gas Chromatography In Forensic Science written by Ian Tebbett and published by CRC Press. This book was released on 1992-10-31 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the application of gas chromatography to various aspects of forensic chemistry. Following an introduction to the basic theory of chromatographic separations, the text discusses specific issues, such as drug analysis, fires and explosives, alcohol and toxicology.