The Experts below are selected from a list of 219 Experts worldwide ranked by ideXlab platform
Chanbasha Basheer - One of the best experts on this subject based on the ideXlab platform.
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Determination of trace level chemical warfare Agents in water and slurry samples using hollow fibre-protected liquid-phase microextraction followed by gas chromatography-mass spectrometry.
Journal of chromatography. A, 2006Co-Authors: Chanbasha BasheerAbstract:A simple and solvent-minimised sample preparation technique based on hollow fibre-protected liquid-phase microextraction was investigated for the gas chromatography/mass spectrometric analysis of chemical warfare Agents in water and slurry samples. The chemical warfare Agents included four nerve Agents and a Blister Agent. Parameters such as extraction solvent, salt concentration, stirring speed and extraction time were optimised using spiked deionised water samples. The technique provided a linear range of two orders of magnitude, good repeatability (RSDs < 10%, n = 6), good linearity (r2 >or= 0.995) and limits of detection (LODs) in the range of 0.02-0.09 microg l(-1) (S/N = 3) under full scan mode. The optimised technique was also applied to more complex slurry samples and similar precision (RSD < 15%, n = 3) and limits of detection (0.02-0.2 microgl(-1), S/N = 3) were obtained.
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Determination of trace level chemical warfare Agents in water and slurry samples using hollow fibre-protected liquid-phase microextraction followed by gas chromatography-mass spectrometry.
Journal of Chromatography A, 2006Co-Authors: Chanbasha BasheerAbstract:Abstract A simple and solvent-minimised sample preparation technique based on hollow fibre-protected liquid-phase microextraction was investigated for the gas chromatography/mass spectrometric analysis of chemical warfare Agents in water and slurry samples. The chemical warfare Agents included four nerve Agents and a Blister Agent. Parameters such as extraction solvent, salt concentration, stirring speed and extraction time were optimised using spiked deionised water samples. The technique provided a linear range of two orders of magnitude, good repeatability (RSDs
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Determination of trace level chemical warfare Agents in water and slurry samples using hollow fibre-protected liquid-phase microextraction followed by gas chromatography-mass spectrometry
Journal of Chromatography A, 2006Co-Authors: H.s.n. Lee, Chanbasha BasheerAbstract:A simple and solvent-minimised sample preparation technique based on hollow fibre-protected liquid-phase microextraction was investigated for the gas chromatography/mass spectrometric analysis of chemical warfare Agents in water and slurry samples. The chemical warfare Agents included four nerve Agents and a Blister Agent. Parameters such as extraction solvent, salt concentration, stirring speed and extraction time were optimised using spiked deionised water samples. The technique provided a linear range of two orders of magnitude, good repeatability (RSDs < 10%, n = 6), good linearity (r2 ≥ 0.995) and limits of detection (LODs) in the range of 0.02-0.09 μg l-1 (S/N = 3) under full scan mode. The optimised technique was also applied to more complex slurry samples and similar precision (RSD < 15%, n = 3) and limits of detection (0.02-0.2 μg l-1, S/N = 3) were obtained. © 2006 Elsevier B.V. All rights reserved.
Gary S Selwyn - One of the best experts on this subject based on the ideXlab platform.
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Chemical warfare Agent decontamination studies in the plasma decon chamber
IEEE Transactions on Plasma Science, 2002Co-Authors: H.w. Herrmann, Gary S Selwyn, Jaeyoung Park, M. Jeffery, Ivars Henins, J M WilliamsAbstract:A "plasma decon chamber" has been developed at Los Alamos National Laboratory (LANL), Albuquerque, NM, to study the decontamination of chemical and biological warfare Agents. This technology is targeted at sensitive electronic equipment for which there is currently no acceptable, nondestructive means of decontamination. Chemical reactivity is provided by a downstream flux of reactive radicals such as atomic oxygen and atomic hydrogen, produced in a capacitively coupled plasma. In addition, the decon chamber provides an environment that accelerates the evaporation of chemical Agents from contaminated surfaces by vacuum, heat, and forced convection. Once evaporated, Agents and Agent byproducts are recirculated directly through the plasma, where they undergo further chemical breakdown. Preliminary studies on actual chemical Agents were conducted at the U.S. Army Dugway Proving Ground, Dugway, UT. Exposures were conducted at a system pressure of 30 torr, exposure temperature of 70/spl deg/C, plasma-to-sample standoff distance of 10 cm, and 10% addition of oxygen or hydrogen to a helium balance. This exposure condition was based on optimization studies conducted at LANL on Agent simulants. The Agents studied were VX and soman (GD) nerve Agents and sulfur mustard (HD) Blister Agent, as well as a thickened simulant. All Agents were decontaminated off aluminum substrates to below the detection limit of /spl sim/0.1% of the initial contamination level of approximately 1 mg/cm/sup 2/. For VX, this level of decontamination was achieved in 8-16 min of exposure, while only 2 min were required for the more volatile HD and GD. Evaporation and subsequent gas-phase chemical breakdown in the plasma appears to be the dominant decontamination mechanism for all of the Agents. However, an observed difference in the decontamination process between oxygen and hydrogen indicates that chemical reactivity in the liquid phase also plays an important role.
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Atmospheric pressure plasma jet technology applied to chem/bio decontamination
ICOPS 2000. IEEE Conference Record - Abstracts. 27th IEEE International Conference on Plasma Science (Cat. No.00CH37087), 2000Co-Authors: H.w. Herrmann, Gary S Selwyn, Ivars Henins, J. ParkAbstract:Summary form only given. The possibility of an attack using chemical or biological warfare (CBW) Agents in either a domestic terrorism or military situation has become all too real in recent history. This has been made evident by the 1995 sarin nerve gas attack on the Tokyo subway and the threat of chem/bio warfare in the Persian Gulf and Korea. The U.S. has stepped up efforts in defence against these horrific Agents, particularly in the areas of detection and decontamination. Atmospheric pressure plasma jet (APPJ) technology may provide a much needed method of CBW decontamination which, unlike traditional decon methods, is dry and nondestructive to sensitive equipment and materials. The APPJ discharge uses a high-flow feedgas consisting primarily of an inert carrier gas, such as He, and a small amount of a reactive additive, such as O/sub 2/, which flows between capacitively-coupled electrodes powered at 13.56 MHz. A nonthermal plasma formed between the electrodes generates highly reactive metastable and atomic species of oxygen through energetic electron impact. These reactive species are then directed onto a contaminated surface. The reactive effluent of the APPJ has been shown to effectively neutralize VX nerve Agent as well as simulants for anthrax and mustard Blister Agent. Research efforts are now being directed towards reducing He consumption and increasing the allowable stand-off distance.
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atmospheric pressure plasma jet technology applied to chem bio decontamination
International Conference on Plasma Science, 2000Co-Authors: H.w. Herrmann, Gary S Selwyn, Ivars Henins, Jaeyoung ParkAbstract:Summary form only given. The possibility of an attack using chemical or biological warfare (CBW) Agents in either a domestic terrorism or military situation has become all too real in recent history. This has been made evident by the 1995 sarin nerve gas attack on the Tokyo subway and the threat of chem/bio warfare in the Persian Gulf and Korea. The U.S. has stepped up efforts in defence against these horrific Agents, particularly in the areas of detection and decontamination. Atmospheric pressure plasma jet (APPJ) technology may provide a much needed method of CBW decontamination which, unlike traditional decon methods, is dry and nondestructive to sensitive equipment and materials. The APPJ discharge uses a high-flow feedgas consisting primarily of an inert carrier gas, such as He, and a small amount of a reactive additive, such as O/sub 2/, which flows between capacitively-coupled electrodes powered at 13.56 MHz. A nonthermal plasma formed between the electrodes generates highly reactive metastable and atomic species of oxygen through energetic electron impact. These reactive species are then directed onto a contaminated surface. The reactive effluent of the APPJ has been shown to effectively neutralize VX nerve Agent as well as simulants for anthrax and mustard Blister Agent. Research efforts are now being directed towards reducing He consumption and increasing the allowable stand-off distance.
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decontamination of chemical and biological warfare cbw Agents using an atmospheric pressure plasma jet appj
Physics of Plasmas, 1999Co-Authors: H.w. Herrmann, Jaeyoung Park, Ivars Henins, Gary S SelwynAbstract:The atmospheric pressure plasma jet (APPJ) [A. Schutze et al., IEEE Trans. Plasma Sci. 26, 1685 (1998)] is a nonthermal, high pressure, uniform glow plasma discharge that produces a high velocity effluent stream of highly reactive chemical species. The discharge operates on a feedstock gas (e.g., He/O2/H2O), which flows between an outer, grounded, cylindrical electrode and an inner, coaxial electrode powered at 13.56 MHz rf. While passing through the plasma, the feedgas becomes excited, dissociated or ionized by electron impact. Once the gas exits the discharge volume, ions and electrons are rapidly lost by recombination, but the fast-flowing effluent still contains neutral metastable species (e.g., O2*, He*) and radicals (e.g., O, OH). This reactive effluent has been shown to be an effective neutralizer of surrogates for anthrax spores and mustard Blister Agent. Unlike conventional wet decontamination methods, the plasma effluent does not cause corrosion and it does not destroy wiring, electronics, or mo...
H.w. Herrmann - One of the best experts on this subject based on the ideXlab platform.
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Chemical warfare Agent decontamination studies in the plasma decon chamber
IEEE Transactions on Plasma Science, 2002Co-Authors: H.w. Herrmann, Gary S Selwyn, Jaeyoung Park, M. Jeffery, Ivars Henins, J M WilliamsAbstract:A "plasma decon chamber" has been developed at Los Alamos National Laboratory (LANL), Albuquerque, NM, to study the decontamination of chemical and biological warfare Agents. This technology is targeted at sensitive electronic equipment for which there is currently no acceptable, nondestructive means of decontamination. Chemical reactivity is provided by a downstream flux of reactive radicals such as atomic oxygen and atomic hydrogen, produced in a capacitively coupled plasma. In addition, the decon chamber provides an environment that accelerates the evaporation of chemical Agents from contaminated surfaces by vacuum, heat, and forced convection. Once evaporated, Agents and Agent byproducts are recirculated directly through the plasma, where they undergo further chemical breakdown. Preliminary studies on actual chemical Agents were conducted at the U.S. Army Dugway Proving Ground, Dugway, UT. Exposures were conducted at a system pressure of 30 torr, exposure temperature of 70/spl deg/C, plasma-to-sample standoff distance of 10 cm, and 10% addition of oxygen or hydrogen to a helium balance. This exposure condition was based on optimization studies conducted at LANL on Agent simulants. The Agents studied were VX and soman (GD) nerve Agents and sulfur mustard (HD) Blister Agent, as well as a thickened simulant. All Agents were decontaminated off aluminum substrates to below the detection limit of /spl sim/0.1% of the initial contamination level of approximately 1 mg/cm/sup 2/. For VX, this level of decontamination was achieved in 8-16 min of exposure, while only 2 min were required for the more volatile HD and GD. Evaporation and subsequent gas-phase chemical breakdown in the plasma appears to be the dominant decontamination mechanism for all of the Agents. However, an observed difference in the decontamination process between oxygen and hydrogen indicates that chemical reactivity in the liquid phase also plays an important role.
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Atmospheric pressure plasma jet technology applied to chem/bio decontamination
ICOPS 2000. IEEE Conference Record - Abstracts. 27th IEEE International Conference on Plasma Science (Cat. No.00CH37087), 2000Co-Authors: H.w. Herrmann, Gary S Selwyn, Ivars Henins, J. ParkAbstract:Summary form only given. The possibility of an attack using chemical or biological warfare (CBW) Agents in either a domestic terrorism or military situation has become all too real in recent history. This has been made evident by the 1995 sarin nerve gas attack on the Tokyo subway and the threat of chem/bio warfare in the Persian Gulf and Korea. The U.S. has stepped up efforts in defence against these horrific Agents, particularly in the areas of detection and decontamination. Atmospheric pressure plasma jet (APPJ) technology may provide a much needed method of CBW decontamination which, unlike traditional decon methods, is dry and nondestructive to sensitive equipment and materials. The APPJ discharge uses a high-flow feedgas consisting primarily of an inert carrier gas, such as He, and a small amount of a reactive additive, such as O/sub 2/, which flows between capacitively-coupled electrodes powered at 13.56 MHz. A nonthermal plasma formed between the electrodes generates highly reactive metastable and atomic species of oxygen through energetic electron impact. These reactive species are then directed onto a contaminated surface. The reactive effluent of the APPJ has been shown to effectively neutralize VX nerve Agent as well as simulants for anthrax and mustard Blister Agent. Research efforts are now being directed towards reducing He consumption and increasing the allowable stand-off distance.
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atmospheric pressure plasma jet technology applied to chem bio decontamination
International Conference on Plasma Science, 2000Co-Authors: H.w. Herrmann, Gary S Selwyn, Ivars Henins, Jaeyoung ParkAbstract:Summary form only given. The possibility of an attack using chemical or biological warfare (CBW) Agents in either a domestic terrorism or military situation has become all too real in recent history. This has been made evident by the 1995 sarin nerve gas attack on the Tokyo subway and the threat of chem/bio warfare in the Persian Gulf and Korea. The U.S. has stepped up efforts in defence against these horrific Agents, particularly in the areas of detection and decontamination. Atmospheric pressure plasma jet (APPJ) technology may provide a much needed method of CBW decontamination which, unlike traditional decon methods, is dry and nondestructive to sensitive equipment and materials. The APPJ discharge uses a high-flow feedgas consisting primarily of an inert carrier gas, such as He, and a small amount of a reactive additive, such as O/sub 2/, which flows between capacitively-coupled electrodes powered at 13.56 MHz. A nonthermal plasma formed between the electrodes generates highly reactive metastable and atomic species of oxygen through energetic electron impact. These reactive species are then directed onto a contaminated surface. The reactive effluent of the APPJ has been shown to effectively neutralize VX nerve Agent as well as simulants for anthrax and mustard Blister Agent. Research efforts are now being directed towards reducing He consumption and increasing the allowable stand-off distance.
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decontamination of chemical and biological warfare cbw Agents using an atmospheric pressure plasma jet appj
Physics of Plasmas, 1999Co-Authors: H.w. Herrmann, Jaeyoung Park, Ivars Henins, Gary S SelwynAbstract:The atmospheric pressure plasma jet (APPJ) [A. Schutze et al., IEEE Trans. Plasma Sci. 26, 1685 (1998)] is a nonthermal, high pressure, uniform glow plasma discharge that produces a high velocity effluent stream of highly reactive chemical species. The discharge operates on a feedstock gas (e.g., He/O2/H2O), which flows between an outer, grounded, cylindrical electrode and an inner, coaxial electrode powered at 13.56 MHz rf. While passing through the plasma, the feedgas becomes excited, dissociated or ionized by electron impact. Once the gas exits the discharge volume, ions and electrons are rapidly lost by recombination, but the fast-flowing effluent still contains neutral metastable species (e.g., O2*, He*) and radicals (e.g., O, OH). This reactive effluent has been shown to be an effective neutralizer of surrogates for anthrax spores and mustard Blister Agent. Unlike conventional wet decontamination methods, the plasma effluent does not cause corrosion and it does not destroy wiring, electronics, or mo...
H.s.n. Lee - One of the best experts on this subject based on the ideXlab platform.
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Determination of trace level chemical warfare Agents in water and slurry samples using hollow fibre-protected liquid-phase microextraction followed by gas chromatography-mass spectrometry
Journal of Chromatography A, 2006Co-Authors: H.s.n. Lee, Chanbasha BasheerAbstract:A simple and solvent-minimised sample preparation technique based on hollow fibre-protected liquid-phase microextraction was investigated for the gas chromatography/mass spectrometric analysis of chemical warfare Agents in water and slurry samples. The chemical warfare Agents included four nerve Agents and a Blister Agent. Parameters such as extraction solvent, salt concentration, stirring speed and extraction time were optimised using spiked deionised water samples. The technique provided a linear range of two orders of magnitude, good repeatability (RSDs < 10%, n = 6), good linearity (r2 ≥ 0.995) and limits of detection (LODs) in the range of 0.02-0.09 μg l-1 (S/N = 3) under full scan mode. The optimised technique was also applied to more complex slurry samples and similar precision (RSD < 15%, n = 3) and limits of detection (0.02-0.2 μg l-1, S/N = 3) were obtained. © 2006 Elsevier B.V. All rights reserved.
Richard D Noble - One of the best experts on this subject based on the ideXlab platform.
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breathable polydopamine coated nanoporous membranes that selectively reject nerve and Blister Agent simulant vapors
Industrial & Engineering Chemistry Research, 2019Co-Authors: Gregory E Dwulet, Sarah M Dischinger, Michael J Mcgrath, Andrew J Basalla, John J Malecha, Richard D NobleAbstract:A laminated thin-film composite (TFC) membrane system consisting of an ultrafiltration support, an ordered, nanoporous, polymerized lyotropic liquid crystal (LLC) intermediate layer, and an ultrathin, dense polydopamine top layer was developed for use as a “breathable” chemical-protective garment material. These membranes exhibit a high water vapor transport rate (ca. 500 g m–2 day–1) and excellent rejection of both CEES (a Blister Agent simulant) and DMMP (a nerve Agent simulant) vapors under ambient conditions. The (water:CEES) and (water:DMMP) molar vapor selectivity values of this new composite membrane system were found to be 170 ± 40 and >3400, respectively, which exceed those of any previously reported LLC-based membrane system.
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ionic liquid gel based containment and decontamination coating for Blister Agent contacted substrates
Chemistry of Materials, 2012Co-Authors: Bret A Voss, Richard D NobleAbstract:Current methods to contain and decontaminate materials contacted by toxic chemical warfare Agents (CWAs) have disadvantages with respect to ease of delivery, portability, and effectiveness on porous substrates. A portable, easy-to-use, spreadable coating that immediately acts as a barrier to contain CWA vapors on contacted substrates and also decontaminates soaked-in CWAs is highly desired. A new type of decontaminating barrier coating for sulfur mustard (i.e., Blister Agent) CWAs has been developed that is made of (1) a spreadable nonvolatile, fluid matrix based on a room-temperature ionic liquid (RTIL), (2) an organic gelator that acts as a solidifying Agent to help the applied coating adhere to and prevent runoff from angled or vertical surfaces, and (3) a polyamine that acts as a reAgent to chemically degrade and help draw out adsorbed Blister Agent. When applied to porous and nonporous substrates contacted with 2-chloroethyl ethyl sulfide (CEES, a mustard Agent simulant), this spreadable, soft solid ...