Science.gov

Sample records for chemical agent detector

  1. Joint Chemical Agent Detector (JCAD): the future of chemical agent detection

    NASA Astrophysics Data System (ADS)

    Laljer, Charles E.; Owen, Jeffery L.

    2002-06-01

    The Joint Chemical Agent Detector (JCAD) will provide state of the art chemical warfare agent detection capability to ground vehicle operators. Intelligence sources estimate that over twenty counties have active chemical weapons programs. The spread of chemical weapons to third world nations, coupled with the potential for US involvement in these areas in an operational or support capacity, increases the probability that the Joint Services may encounter chemical agents and toxic industrial materials anywhere in the world. Currently, fielded chemical agent detectors are bulky, labor intensive, and subject to false readings. No legacy detector is sensitive enough to provide detection and warning of the low dose hazards associated with miosis contamination. The JCAD will provide a small, lightweight chemical agent detector for vehicle interiors, aircraft, individual personnel, shipboard, and fixed site locations. The system provides a common detection components across multi-service platforms. This common detector system will allow the Joint Services to use the same operational and support concept for more efficient utilization of resources. The JCAD will detect, identify, quantify, and warn of the presence of chemical agents prior to onset of miosis. Upon detection of chemical agents, the detector will provide local and remote audible and visual alarms to the operators. Advance warning will provide the vehicle crew with the time necessary to protect themselves from the lethal effects of chemical agents. The JCAD will also be capable of being upgraded to protect against future chemical agent threats. The JCAD will provide the vehicle operators with the warning necessary to survive and fight in a chemical warfare agent threat environment.

  2. Joint chemical agent detector (JCAD): the future of chemical agent detection

    NASA Astrophysics Data System (ADS)

    Laljer, Charles E.

    2003-08-01

    The Joint Chemical Agent Detector (JCAD) has continued development through 2002. The JCAD has completed Contractor Validation Testing (CVT) that included chemical warfare agent testing, environmental testing, electromagnetic interferent testing, and platform integration validation. The JCAD provides state of the art chemical warfare agent detection capability to military and homeland security operators. Intelligence sources estimate that over twenty countries have active chemical weapons programs. The spread of weapons of mass destruction (and the industrial capability for manufacture of these weapons) to third world nations and terrorist organizations has greatly increased the chemical agent threat to U.S. interests. Coupled with the potential for U.S. involvement in localized conflicts in an operational or support capacity, increases the probability that the military Joint Services may encounter chemical agents anywhere in the world. The JCAD is a small (45 in3), lightweight (2 lb.) chemical agent detector for vehicle interiors, aircraft, individual personnel, shipboard, and fixed site locations. The system provides a common detection component across multi-service platforms. This common detector system will allow the Joint Services to use the same operational and support concept for more efficient utilization of resources. The JCAD detects, identifies, quantifies, and warns of the presence of chemical agents prior to onset of miosis. Upon detection of chemical agents, the detector provides local and remote audible and visual alarms to the operators. Advance warning will provide the vehicle crew and other personnel in the local area with the time necessary to protect themselves from the lethal effects of chemical agents. The JCAD is capable of being upgraded to protect against future chemical agent threats. The JCAD provides the operator with the warning necessary to survive and fight in a chemical warfare agent threat environment.

  3. I-SCAD® standoff chemical agent detector overview

    NASA Astrophysics Data System (ADS)

    Popa, Mirela O.; Griffin, Matthew T.

    2012-06-01

    This paper presents a system-level description of the I-SCAD® Standoff Chemical Agent Detector, a passive Fourier Transform InfraRed (FTIR) based remote sensing system, for detecting chemical vapor threats. The passive infrared detection system automatically searches the 7 to 14 micron region of the surrounding atmosphere for agent vapor clouds. It is capable of operating while on the move to accomplish reconnaissance, surveillance, and contamination avoidance missions. Additionally, the system is designed to meet the needs for application on air and sea as well as ground mobile and fixed site platforms. The lightweight, passive, and fully automatic detection system scans the surrounding atmosphere for chemical warfare agent vapors. It provides on-the-move, 360-deg coverage from a variety of tactical and reconnaissance platforms at distances up to 5 km. The core of the system is a rugged Michelson interferometer with a flexure spring bearing mechanism and bi-directional data acquisition capability. The modular system design facilitates interfacing to many platforms. A Reduced Field of View (RFOV) variant includes novel modifications to the scanner subcomponent assembly optical design that gives extended performance in detection range and detection probability without sacrificing existing radiometric sensitivity performance. This paper will deliver an overview of system.

  4. Chemical warfare agent detectors probe the fogs of war

    SciTech Connect

    Ember, L.R. )

    1994-08-01

    The air-power-dominated Persian Gulf War was the largest massing of coalition forces since World War II. This short conflict left its own intriguing legacy of unanswered questions. Were chemical weapons used in the theater of war Some US Allies, many US service members, and a US Senator believe they were. Yet both US and U.K. defense establishments offer emphatic denials. If Saddam Hussein didn't use chemical weapons, how can the multitude of warning alarms that sounded, alarms indicating the presence of these warfare agents, be explained Did the chemical warfare (CW) agent monitors and detectors the US deployed operate properly And were they sensitive enough to detect not just militarily significant levels, for which troops would have had to don full protective gear, but also very low concentrations of these weapons, levels that Sen. Richard C. Shelby (D.-Ala.) believes may be responsible for the illnesses many Gulf War veterans are now experiencing In this paper, the author addressed these questions.

  5. Joint service lightweight standoff chemical agent detector reduced field-of-view

    NASA Astrophysics Data System (ADS)

    Popa, Mirela O.; Flanagan, Michael J.; Despard, V. Boyd; Griffin, Matthew T.; Engel, James R.

    2010-04-01

    A Reduced Field of View (RFOV) Fourier Transform Infrared (FTIR) system for standoff detection of chemical agents demonstrated improved detection at range during field testing. The RFOV system, from the original design parameter of 1.5 degree (27 milliradians) to 0.5 degrees (9 milliradians), includes novel modifications to the scanner assembly optical design to reduce the FOV without sacrificing existing radiometric sensitivity performance. The design modifications also allow for a straightforward retrofit of existing Joint Service Lightweight Standoff Chemical Agent Detectors (JSLSCAD). This paper will deliver an overview of the design and test results from field trials of the system as a function of range and environmental conditions.

  6. Overview of the joint services lightweight standoff chemical agent detector (JSLSCAD)

    NASA Astrophysics Data System (ADS)

    Hammond, Barney; Popa, Mirela

    2005-05-01

    This paper presents a system-level description of the Joint Services Lightweight Standoff Chemical Agent Detector (JSLSCAD). JSLSCAD is a passive Fourier Transform InfraRed (FTIR) based remote sensing system for detecting chemical warfare agents. Unlike predecessor systems, JSLSCAD is capable of operating while on the move to accomplish reconnaissance, surveillance, and contamination avoidance missions. Additionally, the system is designed to meet the needs for application on air and sea as well as ground mobile and fixed site platforms. The core of the system is a rugged Michelson interferometer with a flexure spring bearing mechanism and bi-directional data acquisition capability. The sensor is interfaced to a small, high performance spatial scanner that provides high-speed, two-axis area coverage. Command, control, and processing electronics have been coupled with real time control software and robust detection/discrimination algorithms. Operator interfaces include local and remote options in addition to interfaces to external communications networks. The modular system design facilitates interfacing to the many platforms targeted for JSLSCAD.

  7. Chemical warfare detectors worldwide

    SciTech Connect

    Corriveau, J.

    1995-06-01

    The purpose of this presentation is to provide information on the principal technologies used to detect and identify chemical warfare (CW) agents. Detectors of harmful CW agents may be grouped into three major categories based on their operating principles. The three technologies involved are biochemical, ion mobility spectrometry (IMS), and flame photometry (FP). Once a chemical agent has been detected by one of these means, the presence must often be {open_quotes}confirmed{close_quotes} by a second test that is based on a different technology. Two major means of confirming the presence of a chemical agent are mass spectrometry (MS) and {open_quotes}classical{close_quotes} wet chemistry.

  8. Recent developments in sorbent coatings and chemical detectors at the Naval Research Laboratory for explosives and chemical agents

    NASA Astrophysics Data System (ADS)

    Houser, Eric J.; McGill, Robert A.; Nguyen, Viet K.; Chung, Russell; Weir, David W.

    2000-08-01

    New chemiselective polymers have been developed to enhance the nitroaromatic sorption properties of coated acoustic wave (AW) devices. The sensitivity and selectivity of polymer-based sensors depends on several factors including the chemiselective coating used, the physical properties of the vapor(s) of interest, the selected transducer, and the operating conditions. Detection limits with the coated SAW sensors, tested under laboratory conditions, are determined to be < 100 parts per trillion for 2,4-dinitrotoluene. A new SAW based chemical vapor detector the NRL p-CAD has been developed with dramatically improved signal kinetics offering T95 response times of less than 0.1 second for a wide range of organic compounds including the nerve agent simulant and agent precursor material dimethylmethylphosphonate. In addition, the NRL p-CAD system offers a rapid 2s baseline reset virtually eliminating baseline drift issues associated with changes in temperature and relative humidity. The p-CAD system has been successfully tested in both ground and unmanned aerial vehicle testing.

  9. A 'chemically-gated' photoresponsive compound as a visible detector for organophosphorus nerve agents.

    PubMed

    Nourmohammadian, Farahnaz; Wu, Tuoqi; Branda, Neil R

    2011-10-21

    We describe a versatile and convenient visible detection method for organophosphorus compounds based on a colorless 'pro-photoresponsive' organic molecule that undergoes photochemical ring-closing to produce a colored isomer only after it reacts with vapors of the phosphorylating agent. PMID:21901219

  10. Chemical crowd control agents.

    PubMed

    Menezes, Ritesh G; Hussain, Syed Ather; Rameez, Mansoor Ali Merchant; Kharoshah, Magdy A; Madadin, Mohammed; Anwar, Naureen; Senthilkumaran, Subramanian

    2016-03-01

    Chemical crowd control agents are also referred to as riot control agents and are mainly used by civil authorities and government agencies to curtail civil disobedience gatherings or processions by large crowds. Common riot control agents used to disperse large numbers of individuals into smaller, less destructive, and more easily controllable numbers include chloroacetophenone, chlorobenzylidenemalononitrile, dibenzoxazepine, diphenylaminearsine, and oleoresin capsicum. In this paper, we discuss the emergency medical care needed by sufferers of acute chemical agent contamination and raise important issues concerning toxicology, safety and health. PMID:26658556

  11. Chemical warfare agents.

    PubMed

    Ganesan, K; Raza, S K; Vijayaraghavan, R

    2010-07-01

    Among the Weapons of Mass Destruction, chemical warfare (CW) is probably one of the most brutal created by mankind in comparison with biological and nuclear warfare. Chemical weapons are inexpensive and are relatively easy to produce, even by small terrorist groups, to create mass casualties with small quantities. The characteristics of various CW agents, general information relevant to current physical as well as medical protection methods, detection equipment available and decontamination techniques are discussed in this review article. A brief note on Chemical Weapons Convention is also provided. PMID:21829312

  12. Chemical warfare agents

    PubMed Central

    Ganesan, K.; Raza, S. K.; Vijayaraghavan, R.

    2010-01-01

    Among the Weapons of Mass Destruction, chemical warfare (CW) is probably one of the most brutal created by mankind in comparison with biological and nuclear warfare. Chemical weapons are inexpensive and are relatively easy to produce, even by small terrorist groups, to create mass casualties with small quantities. The characteristics of various CW agents, general information relevant to current physical as well as medical protection methods, detection equipment available and decontamination techniques are discussed in this review article. A brief note on Chemical Weapons Convention is also provided. PMID:21829312

  13. Volatile chemical reagent detector

    DOEpatents

    Chen, Liaohai; McBranch, Duncan; Wang, Rong; Whitten, David

    2004-08-24

    A device for detecting volatile chemical reagents based on fluorescence quenching analysis that is capable of detecting neutral electron acceptor molecules. The device includes a fluorescent material, a contact region, a light source, and an optical detector. The fluorescent material includes at least one polymer-surfactant complex. The polymer-surfactant complex is formed by combining a fluorescent ionic conjugated polymer with an oppositely charged surfactant. The polymer-surfactant complex may be formed in a polar solvent and included in the fluorescent material as a solution. Alternatively, the complex may be included in the fluorescent material as a thin film. The use of a polymer-surfactant complex in the fluorescent material allows the device to detect both neutral and ionic acceptor molecules. The use of a polymer-surfactant complex film allows the device and the fluorescent material to be reusable after exposing the fluorescent material to a vacuum for limited time.

  14. Development of a chemical vision spectrometer to detect chemical agents.

    SciTech Connect

    Demirgian, J.

    1999-02-23

    This paper describes initial work in developing a no-moving-parts hyperspectral-imaging camera that provides both a thermal image and specific identification of chemical agents, even in the presence of nontoxic plumes. The camera uses enhanced stand-off chemical agent detector (ESCAD) technology based on a conventional thermal-imaging camera interfaced with an acousto-optical tunable filter (AOTF). The AOTF is programmed to allow selected spectral frequencies to reach the two dimensional array detector. These frequencies are combined to produce a spectrum that is used for identification. If a chemical agent is detected, pixels containing the agent-absorbing bands are given a colored hue to indicate the presence of the agent. In test runs, two thermal-imaging cameras were used with a specially designed vaporizer capable of controlled low-level (low ppm-m) dynamic chemical releases. The objective was to obtain baseline information about detection levels. Dynamic releases allowed for realistic detection scenarios such as low sky, grass, and wall structures, in addition to reproducible laboratory releases. Chemical releases consisted of dimethylmethylphosphonate (DMMP) and methanol. Initial results show that the combination of AOTF and thermal imaging will produce a chemical image of a plume that can be detected in the presence of interfering substances.

  15. Differential mobility spectroscopy for chemical agent detection

    NASA Astrophysics Data System (ADS)

    Griffin, M. Todd

    2006-05-01

    General Dynamics ATP (GDATP) and Sionex Corporation (Sionex) are carrying out a cooperative development for a handheld chemical agent detector, being called JUNO TM, which will have lower false positives, higher sensitivity, and improved interference rejection compared with presently available detectors. This enhanced performance is made possible by the use of a new principle of ion separation called Differential Mobility Spectrometry (DMS). The enhanced selectivity is provided by the field tunable nature of the Sionex differential mobility technology (microDMxTM) which forms the analytical heart of the JUNO system and enables fingerprinting of molecules by characterization of the ionized molecular behavior under multiple electric field conditions. This enhanced selectivity is valuable in addressing not only the traditional list of chemical warfare agents (CWA) but also the substantial list of Toxic Industrial Compounds (TICs) and Toxic Industrial Materials (TIMs) which may be released in warfare or terrorist situations. Experimental results showing the ability of the microDMx to reject interferences, detect and resolve live agents are presented. An additional breakthrough in the technology was realized by operating the device at a reduced pressure of around 0.5 atmospheres. This reduced pressure operation resulted in roughly doubling the spectrometers resolution over what has previously been reported [1]. Advances have also been made in power consumption and packaging leading to a device suitable for portable, handheld, applications. Experimental results illustrating the performance of the microDMx technology employed in JUNO are highlighted.

  16. IMS software developments for the detection of chemical warfare agent

    NASA Technical Reports Server (NTRS)

    Klepel, ST.; Graefenhain, U.; Lippe, R.; Stach, J.; Starrock, V.

    1995-01-01

    Interference compounds like gasoline, diesel, burning wood or fuel, etc. are presented in common battlefield situations. These compounds can cause detectors to respond as a false positive or interfere with the detector's ability to respond to target compounds such as chemical warfare agents. To ensure proper response of the ion mobility spectrometer to chemical warfare agents, two special software packages were developed and incorporated into the Bruker RAID-1. The programs suppress interferring signals caused by car exhaust or smoke gases resulting from burning materials and correct the influence of variable sample gas humidity which is important for detection and quantification of blister agents like mustard gas or lewisite.

  17. Kromoscopy for detection of chemical warfare agents

    NASA Astrophysics Data System (ADS)

    Ewing, Kenneth J.; Sanghera, Jas; Aggarwal, Ishwar D.; Block, Myron J.

    2004-12-01

    The ability of a Kromoscope to discriminate between chemical warfare agent simulants and toxic industrial chemicals is evaluated. The Kromoscope response to the simulants DMMP and DIMP is compared to a pesticide (diazanon) and cyclopentanol. The response of a mid-infrared Kromoscope to the nerve agents VX and GB and the stimulant DF are calculated.

  18. Chemical warfare. Nerve agent poisoning.

    PubMed

    Holstege, C P; Kirk, M; Sidell, F R

    1997-10-01

    The threat of civilian and military casualties from nerve agent exposure has become a greater concern over the past decade. After rapidly assessing that a nerve agent attack has occurred, emphasis must be placed on decontamination and protection of both rescuers and medical personnel from exposure. The medical system can become rapidly overwhelmed and strong emotional reactions can confuse the clinical picture. Initially, care should first be focused on supportive care, with emphasis toward aggressive airway maintenance and decontamination. Atropine should be titrated, with the goal of therapy being drying of secretions and the resolution of bronchoconstriction and bradycardia. Early administration of pralidoxime chloride maximizes antidotal efficacy. Benzodiazepines, in addition to atropine, should be administered if seizures develop. Early, aggressive medical therapy is the key to prevention of the morbidity and mortality associated with nerve agent poisoning. PMID:9330846

  19. Characterization of chemical agent transport in paints.

    PubMed

    Willis, Matthew P; Gordon, Wesley; Lalain, Teri; Mantooth, Brent

    2013-09-15

    A combination of vacuum-based vapor emission measurements with a mass transport model was employed to determine the interaction of chemical warfare agents with various materials, including transport parameters of agents in paints. Accurate determination of mass transport parameters enables the simulation of the chemical agent distribution in a material for decontaminant performance modeling. The evaluation was performed with the chemical warfare agents bis(2-chloroethyl) sulfide (distilled mustard, known as the chemical warfare blister agent HD) and O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX), an organophosphate nerve agent, deposited on to two different types of polyurethane paint coatings. The results demonstrated alignment between the experimentally measured vapor emission flux and the predicted vapor flux. Mass transport modeling demonstrated rapid transport of VX into the coatings; VX penetrated through the aliphatic polyurethane-based coating (100 μm) within approximately 107 min. By comparison, while HD was more soluble in the coatings, the penetration depth in the coatings was approximately 2× lower than VX. Applications of mass transport parameters include the ability to predict agent uptake, and subsequent long-term vapor emission or contact transfer where the agent could present exposure risks. Additionally, these parameters and model enable the ability to perform decontamination modeling to predict how decontaminants remove agent from these materials. PMID:23872337

  20. History of chemical and biological warfare agents.

    PubMed

    Szinicz, L

    2005-10-30

    Chemical and biological warfare agents constitute a low-probability, but high-impact risk both to the military and to the civilian population. The use of hazardous materials of chemical or biological origin as weapons and for homicide has been documented since ancient times. The first use of chemicals in terms of weapons of mass destruction goes back to World War I, when on April 22, 1915 large amounts of chlorine were released by German military forces at Ypres, Belgium. Until around the 1970s of the 20th century, the awareness of the threat by chemical and biological agents had been mainly confined to the military sector. In the following time, the development of increasing range delivery systems by chemical and biological agents possessors sensitised public attention to the threat emanating from these agents. Their proliferation to the terrorists field during the 1990s with the expanding scale and globalisation of terrorist attacks suggested that these agents are becoming an increasing threat to the whole world community. The following article gives a condensed overview on the history of use and development of the more prominent chemical and biological warfare agents. PMID:16111798

  1. A New Understanding of Chemical Agent Release

    SciTech Connect

    Nakafuji, G; Greenman, R; Theofanous, T

    2002-07-24

    The evolution of thickened chemical agent released at supersonic velocities, due to a missile defense intercept or a properly functioning warhead, has been misunderstood. Current and historical experimental and modeling efforts have attributed agent breakup to a variety of droplet breakup mechanisms. According to this model, drops of agent fragment into subsequent generations of smaller drops until a stable drop size is reached. Recent experimental data conducted in a supersonic wind tunnel show that agent breakup is not driven by any droplet breakup mechanism. The breakup of agent is instead governed by viscoelastic behavior and aerodynamic history effects. This viscoelastic breakup mechanism results in the formation of threads and sheets of liquid, instead of drops. The evolution and final state of agent released has broad implications not only for aerobreakup models, but also for all atmospheric dispersion models.

  2. Laser interrogation of surface agents (LISA) for chemical agent reconnaissance

    NASA Astrophysics Data System (ADS)

    Higdon, N. S.; Chyba, Thomas H.; Richter, Dale A.; Ponsardin, Patrick L.; Armstrong, Wayne T.; Lobb, C. T.; Kelly, Brian T.; Babnick, Robert D.; Sedlacek, Arthur J., III

    2002-06-01

    Laser Interrogation of Surface Agents (LISA) is a new technique which exploits Raman scattering to provide standoff detection and identification of surface-deposited chemical agents. ITT Industries, Advanced Engineering and Sciences Division is developing the LISA technology under a cost-sharing arrangement with the US Army Soldier and Biological Chemical Command for incorporation on the Army's future reconnaissance vehicles. A field-engineered prototype LISA-Recon system is being designed to demonstrate on-the- move measurements of chemical contaminants. In this article, we will describe the LISA technique, data form proof-of- concept measurements, the LISA-Recon design, and some of the future realizations envisioned for military sensing applications.

  3. Detection of electrophilic and nucleophilic chemical agents

    DOEpatents

    McElhanon, James R.; Shepodd, Timothy J.

    2014-08-12

    A "real time" method for detecting chemical agents generally and particularly electrophilic and nucleophilic species by employing tunable, precursor sensor materials that mimic the physiological interaction of these agents to form highly florescent berberine-type alkaloids that can be easily and rapidly detected. These novel precursor sensor materials can be tuned for reaction with both electrophilic (chemical species, toxins) and nucleophilic (proteins and other biological molecules) species. By bonding or otherwise attaching these precursor molecules to a surface or substrate they can be used in numerous applications.

  4. Surface wave chemical detector using optical radiation

    DOEpatents

    Thundat, Thomas G.; Warmack, Robert J.

    2007-07-17

    A surface wave chemical detector comprising at least one surface wave substrate, each of said substrates having a surface wave and at least one measurable surface wave parameter; means for exposing said surface wave substrate to an unknown sample of at least one chemical to be analyzed, said substrate adsorbing said at least one chemical to be sensed if present in said sample; a source of radiation for radiating said surface wave substrate with different wavelengths of said radiation, said surface wave parameter being changed by said adsorbing; and means for recording signals representative of said surface wave parameter of each of said surface wave substrates responsive to said radiation of said different wavelengths, measurable changes of said parameter due to adsorbing said chemical defining a unique signature of a detected chemical.

  5. [Decontamination of chemical and biological warfare agents].

    PubMed

    Seto, Yasuo

    2009-01-01

    Chemical and biological warfare agents (CBWA's) are diverse in nature; volatile acute low-molecular-weight toxic compounds, chemical warfare agents (CWA's, gaseous choking and blood agents, volatile nerve gases and blister agents, nonvolatile vomit agents and lacrymators), biological toxins (nonvolatile low-molecular-weight toxins, proteinous toxins) and microbes (bacteria, viruses, rickettsiae). In the consequence management against chemical and biological terrorism, speedy decontamination of victims, facilities and equipment is required for the minimization of the damage. In the present situation, washing victims and contaminated materials with large volumes of water is the basic way, and additionally hypochlorite salt solution is used for decomposition of CWA's. However, it still remains unsolved how to dispose large volumes of waste water, and the decontamination reagents have serious limitation of high toxicity, despoiling nature against the environments, long finishing time and non-durability in effective decontamination. Namely, the existing decontamination system is not effective, nonspecifically affecting the surrounding non-target materials. Therefore, it is the urgent matter to build up the usable decontamination system surpassing the present technologies. The symposiast presents the on-going joint project of research and development of the novel decontamination system against CBWA's, in the purpose of realizing nontoxic, fast, specific, effective and economical terrorism on-site decontamination. The projects consists of (1) establishment of the decontamination evaluation methods and verification of the existing technologies and adaptation of bacterial organophosphorus hydrolase, (2) development of adsorptive elimination technologies using molecular recognition tools, and (4) development of deactivation technologies using photocatalysis. PMID:19122437

  6. Detection of Electrophilic and Nucleophilic Chemical Agents

    SciTech Connect

    McElhanon, James R.; Shepodd, Timothy J.

    2008-11-11

    A "real time" method for detecting electrophilic and nucleophilic species generally by employing tunable, precursor sensor materials that mimic the physiological interaction of these agents to form highly florescent berberine-type alkaloids that can be easily and rapidly detected. These novel precursor sensor materials can be tuned for reaction with both electrophilic (chemical species, toxins) and nucleophilic (proteins and other biological molecules) species.

  7. Environmental chemistry of chemical warfare agents

    SciTech Connect

    MacNaughton, M.G.; Brewer, J.H.; Ledbetter-Ferrill, J.

    1995-06-01

    This paper summarizes the approach used in the preparation of a Handbook for the Corps of Engineers, Huntsville Division, on the environmental chemistry of chemical warfare agents. The agents GB and HD will be used to illustrate the type of information in the report. Those readers interested in the full report should contact Mr. Arkie Fanning, Huntsville Corps of Engineers at (505) 955-5256. The U.S. Army Corps of Engineers (ACE) has identified approximately 7,200 formerly used defense sites (FUDS) in the United States, some of which are suspected to be contaminated with chemical warfare agents (CWA). The ACE has responsibility for environmental clean-up of FUDS, including site characterization, evaluation and remediation of the site. Thirty-four FUDS and 48 active DOD installations that may contain CWA were identified in an Interim Survey and Analysis Report by the USACMDA Program Manager for Non-Stockpile Chemical Material (NSCM). The chemical agents listed include sulfur mustard (H), lewisite (L), tabun (GA), sarin (GB), VX, hydrogen cyanide (AC), cyanogen chloride (CK), phosgene (CG), BZ, and CS.

  8. The Respiratory Toxicity of Chemical Warefare Agents

    EPA Science Inventory

    Inhalation is one of the most important routes of exposure for chemical warfare agents (CWAs) and thus, the lung remains a critical target of injury. Depending on the mode of action by which the CWAs cause injury, the nature of injury, the location being impacted within the respi...

  9. Environmental mimics of chemical warfare agents.

    PubMed

    Claborn, David M

    2004-12-01

    There are several natural and artificial factors that mimic the effects of chemical warfare agents, thereby causing unwarranted alarm and confusion on the battlefield. Symptoms associated with chemical warfare include paralysis, muscle tremors, heavy salivation, severe burns, blistering, and corrosive skin injuries among others. Similar symptoms can be produced from a variety of environmental sources, artificial and natural. This article reviews several published and unpublished examples of environmental factors that produce syndromes similar to those caused by these agents. Examples of such mimics include pesticides, blistering exudates from insects and plants, various types of bites, and naturally occurring diseases. The potential for confusion caused by these factors is discussed and means of discriminating between warfare agents and naturally occurring events are identified. Recommendations for the use of this information and for needed research are also discussed. PMID:15646185

  10. Bacterial spores and chemical sporicidal agents.

    PubMed Central

    Russell, A D

    1990-01-01

    Bacterial spores are among the most resistant of all living cells to biocides, although the response depends on the stage of sporulation. The development of resistance to some agents such as chlorhexidine occurs much earlier in sporulation than does resistance to glutaraldehyde, which is a very late event. During germination or outgrowth or both, resistance is lost and the cells become as susceptible to biocides as nonsporulating bacteria. Mechanisms of spore resistance to, and the action of, biocides are discussed, and possible means of enhancing antispore activity are considered. The clinical and other uses of sporicidal and sporostatic chemical agents are described. Images PMID:2187595

  11. Chemical Warfare Agent Degradation and Decontamination

    SciTech Connect

    Talmage, Sylvia Smith; Watson, Annetta Paule; Hauschild, Veronique; Munro, Nancy B; King, J.

    2007-02-01

    The decontamination of chemical warfare agents (CWA) from structures, environmental media, and even personnel has become an area of particular interest in recent years due to increased homeland security concerns. In addition to terrorist attacks, scenarios such as accidental releases of CWA from U.S. stockpile sites or from historic, buried munitions are also subjects for response planning. To facilitate rapid identification of practical and effective decontamination approaches, this paper reviews pathways of CWA degradation by natural means as well as those resulting from deliberately applied solutions and technologies; these pathways and technologies are compared and contrasted. We then review various technologies, both traditional and recent, with some emphasis on decontamination materials used for surfaces that are difficult to clean. Discussion is limited to the major threat CWA, namely sulfur mustard (HD, bis(2-chloroethyl)sulfide), VX (O-ethyl S-(2-diisopropylaminoethyl) methylphosphonothioate), and the G-series nerve agents. The principal G-agents are GA (tabun, ethyl N,N-dimethylphosphoramidocyanidate), GB (sarin, isopropyl methylphosphonofluoridate), and GD (soman, pinacolyl methylphosphonofluoridate). The chemical decontamination pathways of each agent are outlined, with some discussion of intermediate and final degradation product toxicity. In all cases, and regardless of the CWA degradation pathway chosen for decontamination, it will be necessary to collect and analyze pertinent environmental samples during the treatment phase to confirm attainment of clearance levels.

  12. JOHNSTON ATOLL CHEMICAL AGENT DISPOSAL SYSTEM (JACADS) CLOSURE PLAN DEVELOPMENT

    EPA Science Inventory

    The JACADS project consists of four incinerators including a liquid chemical agent waste processor, an explosives treatment incinerator and a batch metal parts treatment unit. Its mission was to disassemble and destroy chemcial weapons and bulk chemical agent. This prototypical...

  13. Reactive chromophores for sensitive and selective detection of chemical warfare agents and toxic industrial chemicals

    NASA Astrophysics Data System (ADS)

    Frye-Mason, Greg; Leuschen, Martin; Wald, Lara; Paul, Kateri; Hancock, Lawrence F.

    2005-05-01

    A reactive chromophore developed at MIT exhibits sensitive and selective detection of surrogates for G-class nerve agents. This reporter acts by reacting with the agent to form an intermediate that goes through an internal cyclization reaction. The reaction locks the molecule into a form that provides a strong fluorescent signal. Using a fluorescent sensor platform, Nomadics has demonstrated rapid and sensitive detection of reactive simulants such as diethyl chloro-phosphate (simulant for sarin, soman, and related agents) and diethyl cyanophosphate (simulant for tabun). Since the unreacted chromophore does not fluoresce at the excitation wavelength used for the cyclized reporter, the onset of fluo-rescence can be easily detected. This fluorescence-based detection method provides very high sensitivity and could enable rapid detection at permissible exposure levels. Tests with potential interferents show that the reporter is very selective, with responses from only a few highly toxic, electrophilic chemicals such as phosgene, thionyl chloride, and strong acids such as HF, HCl, and nitric acid. Dimethyl methyl phosphonate (DMMP), a common and inactive simu-lant for other CW detectors, is not reactive enough to generate a signal. The unique selectivity to chemical reactivity means that a highly toxic and hazardous chemical is present when the reporter responds and illustrates that this sensor can provide very low false alarm rates. Current efforts focus on demonstrating the sensitivity and range of agents and toxic industrial chemicals detected with this reporter as well as developing additional fluorescent reporters for a range of chemical reactivity classes. The goal is to produce a hand-held sensor that can sensitively detect a broad range of chemical warfare agent and toxic industrial chemical threats.

  14. Insect-gene-activity detection system for chemical and biological warfare agents and toxic industrial chemicals

    NASA Astrophysics Data System (ADS)

    Mackie, Ryan S.; Schilling, Amanda S.; Lopez, Arturo M.; Rayms-Keller, Alfredo

    2002-02-01

    Detection of multiple chemical and biological weapons (CBW) agents and/or complex mixtures of toxic industrial chemicals (TIC) is imperative for both the commercial and military sectors. In a military scenario, a multi-CBW attack would create confusion, thereby delaying decontamination and therapeutic efforts. In the commercial sector, polluted sites invariably contain a mixture of TIC. Novel detection systems capable of detecting CBW and TIC are sorely needed. While it may be impossible to build a detector capable of discriminating all the possible combinations of CBW, a detection system capable of statistically predicting the most likely composition of a given mixture is within the reach of current emerging technologies. Aquatic insect-gene activity may prove to be a sensitive, discriminating, and elegant paradigm for the detection of CBW and TIC. We propose to systematically establish the expression patterns of selected protein markers in insects exposed to specific mixtures of chemical and biological warfare agents to generate a library of biosignatures of exposure. The predicting capabilities of an operational library of biosignatures of exposures will allow the detection of emerging novel or genetically engineered agents, as well as complex mixtures of chemical and biological weapons agents. CBW and TIC are discussed in the context of war, terrorism, and pollution.

  15. Remote sensing of chemical warfare agent by CO2 -lidar

    NASA Astrophysics Data System (ADS)

    Geiko, Pavel P.; Smirnov, Sergey S.

    2014-11-01

    The possibilities of remote sensing of chemical warfare agent by differential absorption method were analyzed. The CO2 - laser emission lines suitable for sounding of chemical warfare agent with provision for disturbing absorptions by water vapor were choose. The detection range of chemical warfare agents was estimated for a lidar based on CO2 - laser The other factors influencing upon echolocation range were analyzed.

  16. Optical detection of chemical warfare agents and toxic industrial chemicals

    NASA Astrophysics Data System (ADS)

    Webber, Michael E.; Pushkarsky, Michael B.; Patel, C. Kumar N.

    2004-12-01

    We present an analytical model evaluating the suitability of optical absorption based spectroscopic techniques for detection of chemical warfare agents (CWAs) and toxic industrial chemicals (TICs) in ambient air. The sensor performance is modeled by simulating absorption spectra of a sample containing both the target and multitude of interfering species as well as an appropriate stochastic noise and determining the target concentrations from the simulated spectra via a least square fit (LSF) algorithm. The distribution of the LSF target concentrations determines the sensor sensitivity, probability of false positives (PFP) and probability of false negatives (PFN). The model was applied to CO2 laser based photoacosutic (L-PAS) CWA sensor and predicted single digit ppb sensitivity with very low PFP rates in the presence of significant amount of interferences. This approach will be useful for assessing sensor performance by developers and users alike; it also provides methodology for inter-comparison of different sensing technologies.

  17. Chemical warfare agents: estimating oral reference doses.

    PubMed

    Opresko, D M; Young, R A; Faust, R A; Talmage, S S; Watson, A P; Ross, R H; Davidson, K A; King, J

    1998-01-01

    Health risk assessments for sites contaminated with chemical warfare agents require a comparison of the potential levels of exposure with a characterization of the toxic potency of each chemical. For noncancer health effects, toxic potency is expressed in terms of Reference Doses (RfD). A RfD is a daily exposure level or dose (usually expressed in units of milligrams of chemical per kilogram body weight per day) for the human population, including sensitive subpopulations, that is likely to be without an appreciable risk of deleterious effects. A daily exposure at or below the RfD is not likely to be associated with health risks, but as the amount of chemical that an individual is exposed to increases above the RfD, the probability that an adverse effect will occur also increases. A RfD is derived by first examining the available human or animal toxicity data to identify a dose or exposure that corresponds to a no-observed-adverse-effect level (NOAEL) or a lowest-observed-adverse-effect level (LOAEL). The NOAEL is the exposure level at which there are no statistically or biologically significant increases in frequency or severity of adverse effects between the exposed population and its appropriate control. Effects may be produced at this level, but they are not considered to be adverse if they do not result in functional impairment or pathological lesions that affect the performance of the whole organism or which reduce an organism's ability to cope with additional challenge. The LOAEL is the lowest exposure level at which there are statistically or biologically significant increases in frequency or severity of adverse effects between the exposed population and its appropriate control. If only a LOAEL is identified by the toxicity data, a NOAEL is estimated by dividing the LOAEL by a factor no greater than 10. This extrapolation factor of 10 or less is termed the LOAEL-to-NOAEL Uncertainty Factor (UFL). The NOAEL is also adjusted by the application of other

  18. Exposure assessment for chemical and physical agents.

    PubMed

    Moretto, Angelo

    2015-01-01

    Exposure assessment to either chemical or physical agents, as applicable, is a necessary step for both etiologic diagnosis of occupational disease and health surveillance of workers. The assessment can be carried out by measurements of concentrations in air of the substance by either fixed or personal samplers. The former give an indication of the general environment, the latter, applied near the mouth of the worker, provide personalized information. Dermal exposure (deposition) and absorption occur in the occupational setting, but their measurement is so complex that there are no routine methods and no exposure limits established. Oral exposure is accidental or associated with poor hygienic practices, is very difficult to assess, and there are no occupational exposure limits of oral intake. Also accidental injuries caused by needles or other sharp objects that might be contaminated by chemicals occur but exposure assessment in this condition is almost impossible. Exposure is also assessed by biologic monitoring that entails measurements of the substance and/or of its metabolite(s) in accessible fluids, generally urine, blood, or expired air. Biochemical changes, e.g., enzyme inhibition, associated with exposure are also measured. The results of these measurements are compared with existing limit values in order to conclude on the safety of the working conditions. Since the limit values are derived with the application of conservative assumptions, there are no fine lines between health and disease. Therefore, in the clinical setting values below the limit can be generally regarded as safe. Values above the limits should be considered in conjunction with all other information to judge on the likelihood that the disease under investigation may have been caused by exposure to the substance. PMID:26563782

  19. [Decontamination of chemical warfare agents by photocatalysis].

    PubMed

    Hirakawa, Tsutomu; Mera, Nobuaki; Sano, Taizo; Negishi, Nobuaki; Takeuchi, Koji

    2009-01-01

    Photocatalysis has been widely applied to solar-energy conversion and environmental purification. Photocatalyst, typically titanium dioxide (TiO(2)), produces active oxygen species under irradiation of ultraviolet light, and can decompose not only conventional pollutants but also different types of hazardous substances at mild conditions. We have recently started the study of photocatalytic decontamination of chemical warfare agents (CWAs) under collaboration with the National Research Institute of Police Science. This article reviews environmental applications of semiconductor photocatalysis, decontamination methods for CWAs, and previous photocatalytic studies applied to CWA degradation, together with some of our results obtained with CWAs and their simulant compounds. The data indicate that photocatalysis, which may not always give a striking power, certainly helps detoxification of such hazardous compounds. Unfortunately, there are not enough data obtained with real CWAs due to the difficulty in handling. We will add more scientific data using CWAs in the near future to develop useful decontamination systems that can reduce the damage caused by possible terrorism. PMID:19122438

  20. The Fate of Chemical Warfare Agents in the Environment

    SciTech Connect

    Talmage, Sylvia Smith; Munro, Nancy B; Watson, Annetta Paule; King, J.; Hauschild, Veronique

    2007-05-01

    Chemical Warfare Agents, Second Edition has been totally revised since the successful first edition and expanded to about three times the length, with many new chapters and much more in-depth consideration of all the topics. The chapters have been written by distinguished international experts in various aspects of chemical warfare agents and edited by an experienced team to produce a clear review of the field. The book now contains a wealth of material on the mechanisms of action of the major chemical warfare agents, including the nerve agent cyclosarin, formally considered to be of secondary importance, as well as ricin and abrin. Chemical Warfare Agents, Second Edition discusses the physico-chemical properties of chemical warfare agents, their dispersion and fate in the environment, their toxicology and management of their effects on humans, decontamination and protective equipment. New chapters cover the experience gained after the use of sarin to attack travelers on the Tokyo subway and how to deal with the outcome of the deployment of riot control agents such as CS gas. This book provides a comprehensive review of chemical warfare agents, assessing all available evidence regarding the medical, technical and legal aspects of their use. It is an invaluable reference work for physicians, public health planners, regulators and any other professionals involved in this field.

  1. Proximal detection of chemical warfare agents using PMIRRAS

    NASA Astrophysics Data System (ADS)

    Petryk, Michael W. P.; Marenco, Armando J.

    2010-04-01

    Non-contact chemical warfare agent detection has been demonstrated on military painted surfaces using polarization modulation infrared reflection-absorption spectroscopy (PMIRRAS). Notably, VX has been detected on chemical agent resistance coating (CARC) paint at a distance of approximately 10 cm. PMIRRAS does not rely on the presence of chemical vapors and is not affected by many common battlefield interferants such as aerosolized dust, water and diesel vapors, etc., making it highly suitable for use in operational environments.

  2. Biomaterials for mediation of chemical and biological warfare agents.

    PubMed

    Russell, Alan J; Berberich, Jason A; Drevon, Geraldine F; Koepsel, Richard R

    2003-01-01

    Recent events have emphasized the threat from chemical and biological warfare agents. Within the efforts to counter this threat, the biocatalytic destruction and sensing of chemical and biological weapons has become an important area of focus. The specificity and high catalytic rates of biological catalysts make them appropriate for decommissioning nerve agent stockpiles, counteracting nerve agent attacks, and remediation of organophosphate spills. A number of materials have been prepared containing enzymes for the destruction of and protection against organophosphate nerve agents and biological warfare agents. This review discusses the major chemical and biological warfare agents, decontamination methods, and biomaterials that have potential for the preparation of decontamination wipes, gas filters, column packings, protective wear, and self-decontaminating paints and coatings. PMID:12704086

  3. Fluorescent sensors for the detection of chemical warfare agents.

    PubMed

    Burnworth, Mark; Rowan, Stuart J; Weder, Christoph

    2007-01-01

    Along with biological and nuclear threats, chemical warfare agents are some of the most feared weapons of mass destruction. Compared to nuclear weapons they are relatively easy to access and deploy, which makes them in some aspects a greater threat to national and global security. A particularly hazardous class of chemical warfare agents are the nerve agents. Their rapid and severe effects on human health originate in their ability to block the function of acetylcholinesterase, an enzyme that is vital to the central nervous system. This article outlines recent activities regarding the development of molecular sensors that can visualize the presence of nerve agents (and related pesticides) through changes of their fluorescence properties. Three different sensing principles are discussed: enzyme-based sensors, chemically reactive sensors, and supramolecular sensors. Typical examples are presented for each class and different fluorescent sensors for the detection of chemical warfare agents are summarized and compared. PMID:17705326

  4. Laser-based instrumentation for the detection of chemical agents

    SciTech Connect

    Hartford, A. Jr.; Sander, R.K.; Quigley, G.P.; Radziemski, L.J.; Cremers, D.A.

    1982-01-01

    Several laser-based techniques are being evaluated for the remote, point, and surface detection of chemical agents. Among the methods under investigation are optoacoustic spectroscopy, laser-induced breakdown spectroscopy (LIBS), and synchronous detection of laser-induced fluorescence (SDLIF). Optoacoustic detection has already been shown to be capable of extremely sensitive point detection. Its application to remote sensing of chemical agents is currently being evaluated. Atomic emission from the region of a laser-generated plasma has been used to identify the characteristic elements contained in nerve (P and F) and blister (S and Cl) agents. Employing this LIBS approach, detection of chemical agent simulants dispersed in air and adsorbed on a variety of surfaces has been achieved. Synchronous detection of laser-induced fluorescence provides an attractive alternative to conventional LIF, in that an artificial narrowing of the fluorescence emission is obtained. The application of this technique to chemical agent simulants has been successfully demonstrated. 19 figures.

  5. Surface-enhanced Raman spectrometry of organophosphorus chemical agents

    SciTech Connect

    Alak, A.M.; Vo-Dinh, T.

    1987-09-01

    Organophosphorus chemical agents have been analyzed by surface-enhanced Raman scattering (SERS) spectrometry. Significant spectral enhancement was achieved with special substrates that were prepared with silver-coated microspheres. Organophosphorus compounds were easily and rapidly measured at nanogram levels. The SERS spectra of eight of these organophosphorus chemical agents are presented. The sensitivity and spectral selectivity of this new spectrochemical technique for trace organic analysis of toxic chemical agents are discussed. Analyses of a two-component mixture and contaminated soil sample extract are illustrated.

  6. Chemical Agents: Personal Cleaning and Disposal of Contaminated Clothing

    MedlinePlus

    ... Facts About Sheltering Facts About Personal Cleaning Public Health Emergency Response Guide Reaching At-Risk Populations MedCon Chemical Agents: Facts About Personal Cleaning and Disposal of Contaminated ...

  7. The induction of synaesthesia with chemical agents: a systematic review

    PubMed Central

    Luke, David P.; Terhune, Devin B.

    2013-01-01

    Despite the general consensus that synaesthesia emerges at an early developmental stage and is only rarely acquired during adulthood, the transient induction of synaesthesia with chemical agents has been frequently reported in research on different psychoactive substances. Nevertheless, these effects remain poorly understood and have not been systematically incorporated. Here we review the known published studies in which chemical agents were observed to elicit synaesthesia. Across studies there is consistent evidence that serotonin agonists elicit transient experiences of synaesthesia. Despite convergent results across studies, studies investigating the induction of synaesthesia with chemical agents have numerous methodological limitations and little experimental research has been conducted. Cumulatively, these studies implicate the serotonergic system in synaesthesia and have implications for the neurochemical mechanisms underlying this phenomenon but methodological limitations in this research area preclude making firm conclusions regarding whether chemical agents can induce genuine synaesthesia. PMID:24146659

  8. Chemical kinetics of cetane number improving agents

    SciTech Connect

    Hashimoto, K.; Akutsu, Y.; Arai, M.; Tamura, M.

    1996-12-31

    The increasing demand for diesel fuels has resulted in the use of greater percentage of cracked distillates having poor ignition properties. The ignition properties of diesel fuels can be rated in terms of their cetane number and diesel fuels having low cetane number may have poor ignition properties such as diesel knock, difficulties to start engines in the cold weather and so on. Such diesel fuels need cetane number improving agents. In the 1940s and 1950s alkyl nitrates, alkyl nitrites and organic peroxides were found to be effective cetane number improving additives. Our recent study suggests that free radicals produced from thermal decomposition just before ignition should have an important role to improve their ignition properties. However no studies on the reaction mechanism for improving effect of these additives have been attempted because of complex nature of spontaneous ignition reaction of hydrocarbons. In order to clarify the reaction mechanism for improving effects of cetane number improving agents. We here have attempted to simulate the spontaneous ignition of n-butane as a model compound in the presence of alkyl nitrites as cetane number improving agents.

  9. Chemical Action of Halogenated Agents in Fire Extinguishing

    NASA Technical Reports Server (NTRS)

    Belles, Frank E.

    1955-01-01

    The action of halogenated agents in preventing flame propagation in fuel-air mixtures in laboratory tests is discussed in terms of a possible chemical mechanism. The mechanism chosen is that of chain-breaking reactions between agent and active particles (hydrogen and oxygen atoms and hydroxyl radicsls). Data from the literature on the flammability peaks of n-heptane agent-air mixtures are treated. Ratings of agent effectiveness in terms of the fuel equivalent of the agent, based on both fuel and agent concentrations at the peak, are proposed as preferable to ratings in terms of agent concentration alone. These fuel-equivalent ratings are roughly correlated by reactivities assigned to halogen and hydrogen atoms in the agent molecules. It is concluded that the presence of hydrogen in agent need not reduce its fire-fighting ability, provided there is enough halogen to make the agent nonflammable. A method is presented for estimating from quenching-distance data a rate constant for the reaction of agent with active particles. A quantitative result is obtained for methyl bromide. This rate constant predicts the observed peak concentration of methyl bromide quite well. However, more data are needed to prove the validity of the method. The assumption that hal.ogenatedagents act mainly by chain-bresking reactions with active particles is consistent with the experimental facts and should help guide the selection of agents for further tests.

  10. Multisensor analyzer detector (MSAD) for low cost chemical and aerosol detection and pattern fusion

    NASA Astrophysics Data System (ADS)

    Swanson, David C.; Merdes, Daniel W.; Lysak, Daniel B., Jr.; Curtis, Richard C.; Lang, Derek C.; Mazzara, Andrew F.; Nicholas, Nicholas C.

    2002-08-01

    MSAD is being developed as a low-cost point detection chemical and biological sensor system designed around an information fusion inference engine that also allows additional sensors to be included in the detection process. The MSAD concept is based on probable cause detection of hazardous chemical vapors and aerosols of either chemical or biological composition using a small portable unit containing an embedded computer system and several integrated sensors with complementary capabilities. The configuration currently envisioned includes a Surface-Enhanced Raman Spectroscopy (SERS) sensor of chemical vapors and a detector of respirable aerosols based on Fraunhofer diffraction. Additional sensors employing Ion Mobility Spectrometry (IMS), Surface Acoustic Wave (SAW) detection, Flame Photometric Detection (FPD), and other principles are candidates for integration into the device; also, available commercial detectors implementing IMS, SAW, and FPD will be made accessible to the unit through RS232 ports. Both feature and decision level information fusion is supported using a Continuous Inference Network (CINET) of fuzzy logic. Each class of agents has a unique CINET with information inputs from a number of available sensors. Missing or low confidence sensor information is gracefully blended out of the output confidence for the particular agent. This approach constitutes a plug and play arrangement between the sensors and the information pattern recognition algorithms. We are currently doing simulant testing and developing out CINETs for actual agent testing at Edgewood Chemical and Biological Center (ECBC) later this year.

  11. Development of a persistent chemical agent simulation system

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A Persistent Chemical Agent Simulation System was developed (PCASS) to simulate, for force-on-force training exercises, the field environment produced by the presence of persistent chemical agents. Such a simulant system must satisfy several requirements to be of value as a training aid. Specifically, it must provide for realistic training which will generate competency in at least the following areas: (1) detection of the persistent agent presence; (2) proper use of protective equipment and procedures; (3) determination of the extent of contamination; and (4) decontamination of equipment and personnel.

  12. A decontamination study of simulated chemical and biological agents

    NASA Astrophysics Data System (ADS)

    Uhm, Han S.; Lee, Han Y.; Hong, Yong C.; Shin, Dong H.; Park, Yun H.; Hong, Yi F.; Lee, Chong K.

    2007-07-01

    A comprehensive decontamination scheme of the chemical and biological agents, including airborne agents and surface contaminating agents, is presented. When a chemical and biological attack occurs, it is critical to decontaminate facilities or equipments to an acceptable level in a very short time. The plasma flame presented here may provide a rapid and effective elimination of toxic substances in the interior air in isolated spaces. As an example, a reaction chamber, with the dimensions of a 22cm diameter and 30cm length, purifies air with an airflow rate of 5000l/min contaminated with toluene, the simulated chemical agent, and soot from a diesel engine, the simulated aerosol for biological agents. Although the airborne agents in an isolated space are eliminated to an acceptable level by the plasma flame, the decontamination of the chemical and biological agents cannot be completed without cleaning surfaces of the facilities. A simulated sterilization study of micro-organisms was carried out using the electrolyzed ozone water. The electrolyzed ozone water very effectively kills endospores of Bacillus atrophaeus (ATCC 9372) within 3min. The electrolyzed ozone water also kills the vegetative micro-organisms, fungi, and virus. The electrolyzed ozone water, after the decontamination process, disintegrates into ordinary water and oxygen without any trace of harmful materials to the environment.

  13. A decontamination study of simulated chemical and biological agents

    SciTech Connect

    Uhm, Han S.; Lee, Han Y.; Hong, Yong C.; Shin, Dong H.; Park, Yun H.; Hong, Yi F.; Lee, Chong K.

    2007-07-01

    A comprehensive decontamination scheme of the chemical and biological agents, including airborne agents and surface contaminating agents, is presented. When a chemical and biological attack occurs, it is critical to decontaminate facilities or equipments to an acceptable level in a very short time. The plasma flame presented here may provide a rapid and effective elimination of toxic substances in the interior air in isolated spaces. As an example, a reaction chamber, with the dimensions of a 22 cm diameter and 30 cm length, purifies air with an airflow rate of 5000 l/min contaminated with toluene, the simulated chemical agent, and soot from a diesel engine, the simulated aerosol for biological agents. Although the airborne agents in an isolated space are eliminated to an acceptable level by the plasma flame, the decontamination of the chemical and biological agents cannot be completed without cleaning surfaces of the facilities. A simulated sterilization study of micro-organisms was carried out using the electrolyzed ozone water. The electrolyzed ozone water very effectively kills endospores of Bacillus atrophaeus (ATCC 9372) within 3 min. The electrolyzed ozone water also kills the vegetative micro-organisms, fungi, and virus. The electrolyzed ozone water, after the decontamination process, disintegrates into ordinary water and oxygen without any trace of harmful materials to the environment.

  14. Solid-water detoxifying reagents for chemical and biological agents

    DOEpatents

    Hoffman, Dennis M.; Chiu, Ing Lap

    2006-04-18

    Formation of solid-water detoxifying reagents for chemical and biological agents. Solutions of detoxifying reagent for chemical and biological agents are coated using small quantities of hydrophobic nanoparticles by vigorous agitation or by aerosolization of the solution in the presence of the hydrophobic nanoparticles to form a solid powder. For example, when hydrophobic fumed silica particles are shaken in the presence of IN oxone solution in approximately a 95:5-weight ratio, a dry powder results. The hydrophobic silica forms a porous coating of insoluble fine particles around the solution. Since the chemical or biological agent tends to be hydrophobic on contact with the weakly encapsulated detoxifying solution, the porous coating breaks down and the detoxifying reagent is delivered directly to the chemical or biological agent for maximum concentration at the point of need. The solid-water (coated) detoxifying solutions can be blown into contaminated ventilation ducting or other difficult to reach sites for detoxification of pools of chemical or biological agent. Once the agent has been detoxified, it can be removed by flushing the area with air or other techniques.

  15. Review of systemization of the Tooele Chemical Agent Disposal Facility

    SciTech Connect

    1996-07-01

    In 1993, at Tooele Army Depot, Utah, the Army completed construction of the Tooele Chemical Agent Disposal Facility (TOCDF), the first complete facility for destruction of lethal unitary chemical agents and munitions to be built in the continental United States. The TOCDF will employ the Army`s baseline incineration system to destroy the depot`s increment of the nation`s aging unitary chemical stockpile. This book assesses Army changes and improvements to the TOCDF in response to recommendations contained in earlier reports of the committee. It assesses aspects of the facility`s readiness for safe agent handling and destruction operations, its agent monitoring system, and its site specific risk assessment.

  16. LOW VOLATILE ORGANIC COMPOUND (VOC) CHEMICAL AGENT RESISTANT COATING (CARC)

    EPA Science Inventory

    Chemical warfare causes many problems on the battlefield, among which is decontamination of exposed equipment. Because of this threat, the US Army ahs required the use of a Chemical Agent Resistant Coating (CARC) system on its equipment, beginning in FY 85. The equipment covere...

  17. Bubble chamber as a trace chemical detector

    SciTech Connect

    Luo, X.; McCreary, E.I.; Atencio, J.H.; McCown, A.W.; Sander, R.K.

    1998-08-01

    A novel concept for trace chemical analysis in liquid has been demonstrated. The technique utilizes light absorption in a superheated liquid. Although a superheated liquid is thermodynamically unstable, a high degree of superheating can be dynamically achieved for a short period of time. During this time the superheated liquid is extremely sensitive to boiling at nucleation sites produced by energy deposition. Observation of bubbles in the superheated liquid in some sense provides amplification of the initial energy deposition. Bubble chambers containing superheated liquids have been used to detect energetic particles; now a bubble chamber is used to detect a trace chemical in superheated liquid propane by observing bubble formation initiated by optical absorption. Crystal violet is used as a test case and can be detected at the subpart-per-10{sup 12} level by using a Nd:YAG laser. The mechanism for bubble formation and ideas for further improvement are discussed. {copyright} 1998 Optical Society of America

  18. Fiber Optic Detector For Liquid Chemical Leaks

    NASA Astrophysics Data System (ADS)

    Luukkala, Mauri; Raatikainen, Pekka; Salo, Olli

    1989-10-01

    This paper describes a simple and economical sensor which employs fiber optics to detect the presence of hazardous liquid chemicals, particularly undiluted hydrocarbons. The device is best suited to monitor the interstitial space of double walled underground storage tanks. Because the sensor is plastic and is situated at the end of a passive and insulating optical fiber the sensor can be considered inherently safe. The optical fiber used for this device can be up to several hundred meters long.

  19. GaN-based micro chemical sensor nodes for early warning chemical agents

    NASA Astrophysics Data System (ADS)

    Son, K.-A.; Yang, B.; Prokopuk, N.; Moon, J. S.; Liao, A.; Gallegos, M.; Yang, J.; Khan, M. A.

    2007-04-01

    We are developing micro chemical sensor nodes that can be used for real time, remote detection and early warning of chemical agent threats. The chemical sensors in our sensor nodes utilize GaN HEMTs (High Electron Mobility Transistors) fabricated with catalytically active transition metal gate electrodes. The GaN HEMT chemical sensors exhibit high sensitivity and selectivity toward chemical agent simulants such as DECNP (Diethyl cyano phosphonate), and this is the first time that chemical agent simulants have been detected with GaN micro sensors. Response time of the GaN HEMT sensor to a chemical species is within a second, and the maximum electronic response speed of the sensor is ~3 GHz. A prototype micro chemical sensor node has been constructed with the GaN sensor, a micro controller, and an RF link. The RF sensor node is operated with a single 3V Li battery, dissipating 15 mW during the RF transmission with 5 dBm output power. The microcontroller allows the operation of the RF sensor nodes with a duty cycle down to 1 %, extending lifetime of the RF sensor nodes over 47 days. Designed to transmit RF signals only at the exposures to chemical agents and produce collective responses to a chemical agent via a sensorweb, the GaN micro chemical sensor nodes seem to be promising for chemical agent beacons.

  20. Destruction of chemical warfare agents using metal-organic frameworks.

    PubMed

    Mondloch, Joseph E; Katz, Michael J; Isley, William C; Ghosh, Pritha; Liao, Peilin; Bury, Wojciech; Wagner, George W; Hall, Morgan G; DeCoste, Jared B; Peterson, Gregory W; Snurr, Randall Q; Cramer, Christopher J; Hupp, Joseph T; Farha, Omar K

    2015-05-01

    Chemical warfare agents containing phosphonate ester bonds are among the most toxic chemicals known to mankind. Recent global military events, such as the conflict and disarmament in Syria, have brought into focus the need to find effective strategies for the rapid destruction of these banned chemicals. Solutions are needed for immediate personal protection (for example, the filtration and catalytic destruction of airborne versions of agents), bulk destruction of chemical weapon stockpiles, protection (via coating) of clothing, equipment and buildings, and containment of agent spills. Solid heterogeneous materials such as modified activated carbon or metal oxides exhibit many desirable characteristics for the destruction of chemical warfare agents. However, low sorptive capacities, low effective active site loadings, deactivation of the active site, slow degradation kinetics, and/or a lack of tailorability offer significant room for improvement in these materials. Here, we report a carefully chosen metal-organic framework (MOF) material featuring high porosity and exceptional chemical stability that is extraordinarily effective for the degradation of nerve agents and their simulants. Experimental and computational evidence points to Lewis-acidic Zr(IV) ions as the active sites and to their superb accessibility as a defining element of their efficacy. PMID:25774952

  1. Destruction of chemical warfare agents using metal-organic frameworks

    NASA Astrophysics Data System (ADS)

    Mondloch, Joseph E.; Katz, Michael J.; Isley, William C., III; Ghosh, Pritha; Liao, Peilin; Bury, Wojciech; Wagner, George W.; Hall, Morgan G.; Decoste, Jared B.; Peterson, Gregory W.; Snurr, Randall Q.; Cramer, Christopher J.; Hupp, Joseph T.; Farha, Omar K.

    2015-05-01

    Chemical warfare agents containing phosphonate ester bonds are among the most toxic chemicals known to mankind. Recent global military events, such as the conflict and disarmament in Syria, have brought into focus the need to find effective strategies for the rapid destruction of these banned chemicals. Solutions are needed for immediate personal protection (for example, the filtration and catalytic destruction of airborne versions of agents), bulk destruction of chemical weapon stockpiles, protection (via coating) of clothing, equipment and buildings, and containment of agent spills. Solid heterogeneous materials such as modified activated carbon or metal oxides exhibit many desirable characteristics for the destruction of chemical warfare agents. However, low sorptive capacities, low effective active site loadings, deactivation of the active site, slow degradation kinetics, and/or a lack of tailorability offer significant room for improvement in these materials. Here, we report a carefully chosen metal-organic framework (MOF) material featuring high porosity and exceptional chemical stability that is extraordinarily effective for the degradation of nerve agents and their simulants. Experimental and computational evidence points to Lewis-acidic ZrIV ions as the active sites and to their superb accessibility as a defining element of their efficacy.

  2. Air monitoring and detection of chemical and biological agents

    SciTech Connect

    Leonelli, J.; Althouse, M.L.

    1999-06-01

    This volume contains the proceedings of SPIE`s remote sensing symposium which was held November 2--3, 1998 in Boston, Massachusetts. Topics of discussion include the following: system simulations, atmospheric modeling, and performance prediction studies of chemical warfare remote sensing technologies; ultraviolet laser-induced fluorescence and aerosol detection methods for remote sensing of biological warfare agents; passive detection methods for remote detection of chemical warfare agents; and lidar-based system performance assessments, demonstrations, and new concepts for chemical warfare/biological warfare detection.

  3. Chemical Microsensors For Detection Of Explosives And Chemical Warfare Agents

    SciTech Connect

    Yang, Xiaoguang; Swanson, Basil I.

    2001-11-13

    An article of manufacture is provided including a substrate having an oxide surface layer and a layer of a cyclodextrin derivative chemically bonded to said substrate, said layer of a cyclodextrin derivative adapted for the inclusion of selected compounds, e.g., nitro-containing organic compounds, therewith. Such an article can be a chemical microsensor capable of detecting a resultant mass change from inclusion of the nitro-containing organic compound.

  4. A Portable System for Nuclear, Chemical Agent and Explosives Identification

    SciTech Connect

    Parker, W.E.; Buckley, W.M.; Kreek, S.A.; Caffrey, A.J.; Mauger, G.J.; Lavietes, A.D.; Dougan, A.D.

    2000-09-29

    The FRIS/PINS hybrid integrates the LLNL-developed Field Radionuclide Identification System (FRIS) with the INEEL-developed Portable Isotopic Neutron Spectroscopy (PINS) chemical assay system to yield a combined general radioisotope, special nuclear material, and chemical weapons/explosives detection and identification system. The PINS system uses a neutron source and a high-purity germanium {gamma}-ray detector. The FRIS system uses an electrochemically cooled germanium detector and its own analysis software to detect and identify special nuclear material and other radioisotopes. The FRIS/PINS combined system also uses the electromechanically-cooled germanium detector. There is no other currently available integrated technology that can combine an active neutron interrogation and analysis capability for CWE with a passive radioisotope measurement and identification capability for special nuclear material.

  5. Fighting nerve agent chemical weapons with enzyme technology.

    PubMed

    LeJeune, K E; Dravis, B C; Yang, F; Hetro, A D; Doctor, B P; Russell, A J

    1998-12-13

    The extreme toxicity of organophosphorous-based compounds has been known since the late 1930s. Starting in the mid-1940s, many nations throughout the world have been producing large quantities of organophosphorous (OP) nerve agents. Huge stockpiles of nerve agents have since developed. There are reportedly more than 200,000 tons of nerve agents in existence worldwide. There is an obvious need for protective clothing capable of guarding an individual from exposure to OP chemical weapons. Also, chemical processes that can effectively demilitarize and detoxify stored nerve agents are in great demand. The new and widely publicized Chemical Weapons Treaty requires such processes to soon be in place throughout the world. Biotechnology may provide the tools necessary to make such processes not only possible, but quite efficient in reducing the nerve agent dilemma. The following paper discusses some of the history in developing enzyme technology against nerve agents. Our laboratory has interest in enhancing the productivity and potential utility of these systems in both demilitarization and decontamination applications. Freeze-dried nerve agent-hydrolyzing enzyme preparations have been shown to be effective in decontaminating gaseous nerve agents. The direct incorporation of nerve agent-hydrolyzing enzymes within cross-linked polyurethane foam matrices during polymer synthesis has been shown to dramatically enhance the productivity of two different enzyme systems. The future goal of such work lies in building a bridge between the clinical application of nerve agent-hydrolyzing enzymes and practical processing techniques that may take advantage of the initial results already achieved in the laboratory. PMID:9928090

  6. NONDESTRUCTIVE IDENTIFICATION OF CHEMICAL WARFARE AGENTS AND EXPLOSIVES BY NEUTRON GENERATOR-DRIVEN PGNAA

    SciTech Connect

    T. R. Twomey; A. J. Caffrey; D. L. Chichester

    2007-02-01

    Prompt gamma-ray neutron activation analysis (PGNAA) is now a proven method for the identification of chemical warfare agents and explosives in military projectiles and storage containers. Idaho National Laboratory is developing a next-generation PGNAA instrument based on the new Ortec Detective mechanically-cooled HPGe detector and a neutron generator. In this paper we review PGNAA analysis of suspect chemical warfare munitions, and we discuss the advantages and disadvantages of replacing the californium-252 radioisotopic neutron source with a compact accelerator neutron generator.

  7. Rapid chemical agent identification by surface-enhanced Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Lee, Yuan-Hsiang; Farquharson, Stuart

    2001-08-01

    Although the Chemical Weapons Convention prohibits the development, production, stockpiling, and use of chemical warfare agents (CWAs), the use of these agents persists due to their low cost, simplicity in manufacturing and ease of deployment. These attributes make these weapons especially attractive to low technology countries and terrorists. The military and the public at large require portable, fast, sensitive, and accurate analyzers to provide early warning of the use of chemical weapons. Traditional laboratory analyzers such as the combination of gas chromatography and mass spectroscopy, although sensitive and accurate, are large and require up to an hour per analysis. New, chemical specific analyzers, such as immunoassays and molecular recognition sensors, are portable, fast, and sensitive, but are plagued by false-positives (response to interferents). To overcome these limitations, we have been investigating the potential of surface-enhanced Raman spectroscopy (SERS) to identify and quantify chemical warfare agents in either the gas or liquid phase. The approach is based on the extreme sensitivity of SERS demonstrated by single molecule detection, a new SERS material that we have developed to allow reproducible and reversible measurements, and the molecular specific information provided by Raman spectroscopy. Here we present SER spectra of chemical agent simulants in both the liquid and gas phase, as well as CWA hydrolysis phase.

  8. Oxidizer gels for detoxification of chemical and biological agents

    DOEpatents

    Hoffman, Dennis M.; McGuire, Raymond R.

    2002-01-01

    A gel composition containing oxidizing agents and thickening or gelling agents is used to detoxify chemical and biological agents by application directly to a contaminated area. The gelling agent is a colloidal material, such as silica, alumina, or alumino-silicate clays, which forms a viscous gel that does not flow when applied to tilted or contoured surfaces. Aqueous or organic solutions of oxidizing agents can be readily gelled with less than about 30% colloidal material. Gel preparation is simple and suitable for field implementation, as the gels can be prepared at the site of decontamination and applied quickly and uniformly over an area by a sprayer. After decontamination, the residue can be washed away or vacuumed up for disposal.

  9. A traceable quantitative infrared spectral database of chemical agents

    NASA Astrophysics Data System (ADS)

    Samuels, Alan C.; Williams, Barry R.; Ben-David, Avishai; Hulet, Melissa; Roelant, Geoffrey J.; Miles, Ronald W., Jr.; Green, Norman; Zhu, Changjiang

    2004-12-01

    Recent experimental field trials have demonstrated the ability of both Fourier transform infrared (FTIR) and active light detection and ranging (LIDAR) sensors to detect particulate matter, including simulants for biological materials. Both systems require a reliable, validated, quantitative database of the mid infrared spectra of the targeted threat agents. While several databases are available, none are validated and traceable to primary standards for reference quality reliability. Most of the existing chemical agent databases have been developed using a bubbler or syringe-fed vapor generator, and all are fraught with errors and uncertainties as a result. In addition, no quantitative condensed phase data on the low volatility chemicals and biological agents have been reported. We are filling this data gap through the systematic measurement of gas phase chemical agent materials generated using a unique vapor-liquid equilibrium approach that allows the quantitation of the cross-sections using a mass measurement calibrated to primary, National Institutes of Standards and Technology (NIST) standards. In addition, we have developed quantitative methods for the measurement of condensed phase materials in both transmission and diffuse reflectance modes. The latter data are valuable for the development of complex index of refraction data, which is required for both system modeling and algorithm development of both FTIR and LIDAR based sensor systems. We will describe our measurement approach and progress toward compiling the first known comprehensive and validated database of both vapor and condensed phase chemical warfare agents.

  10. Ultraviolet Raman scattering from persistent chemical warfare agents

    NASA Astrophysics Data System (ADS)

    Kullander, Fredrik; Wästerby, Pär.; Landström, Lars

    2016-05-01

    Laser induced Raman scattering at excitation wavelengths in the middle ultraviolet was examined using a pulsed tunable laser based spectrometer system. Droplets of chemical warfare agents, with a volume of 2 μl, were placed on a silicon surface and irradiated with sequences of laser pulses. The Raman scattering from V-series nerve agents, Tabun (GA) and Mustard gas (HD) was studied with the aim of finding the optimum parameters and the requirements for a detection system. A particular emphasis was put on V-agents that have been previously shown to yield relatively weak Raman scattering in this excitation band.

  11. Spectral unmixing of agents on surfaces for the Joint Contaminated Surface Detector (JCSD)

    NASA Astrophysics Data System (ADS)

    Slamani, Mohamed-Adel; Chyba, Thomas H.; LaValley, Howard; Emge, Darren

    2007-09-01

    ITT Corporation, Advanced Engineering and Sciences Division, is currently developing the Joint Contaminated Surface Detector (JCSD) technology under an Advanced Concept Technology Demonstration (ACTD) managed jointly by the U.S. Army Research, Development, and Engineering Command (RDECOM) and the Joint Project Manager for Nuclear, Biological, and Chemical Contamination Avoidance for incorporation on the Army's future reconnaissance vehicles. This paper describes the design of the chemical agent identification (ID) algorithm associated with JCSD. The algorithm detects target chemicals mixed with surface and interferent signatures. Simulated data sets were generated from real instrument measurements to support a matrix of parameters based on a Design Of Experiments approach (DOE). Decisions based on receiver operating characteristics (ROC) curves and area-under-the-curve (AUC) measures were used to down-select between several ID algorithms. Results from top performing algorithms were then combined via a fusion approach to converge towards optimum rates of detections and false alarms. This paper describes the process associated with the algorithm design and provides an illustrating example.

  12. The fate of the chemical warfare agent during DNA extraction.

    PubMed

    Wilkinson, Della A; Hulst, Albert G; de Reuver, Leo P J; van Krimpen, Simon H; van Baar, Ben M L

    2007-11-01

    Forensic laboratories do not have the infrastructure to process or store contaminated DNA samples that have been recovered from a crime scene contaminated with chemical or biological warfare agents. Previous research has shown that DNA profiles can be recovered from blood exposed to several chemical warfare agents after the agent has been removed. The fate of four toxic agents, sulfur mustard, sodium 2-fluoroacetate, sarin, and diazinon, in a lysis buffer used in Promega DNA IQ extraction protocol was studied to determine if extraction would render the samples safe. Two independent analytical methods were used per agent, selected from GC-MS, 1H NMR, 19F NMR, (31)P NMR, or LC-ES MS. The methods were validated before use. Determinations were carried out in a semi-quantitative way, by direct comparison to standards. Agent levels in the elution buffer were found to be below the detectable limits for mustard, sarin, sodium 2-fluoroacetate or low (<0.02 mg/mL) for diazinon. Therefore, once extracted these DNA samples could be safely processed in a forensic laboratory. PMID:18093062

  13. Appendix C. Collection of Samples for Chemical Agent Analysis

    SciTech Connect

    Koester, C; Thompson, C; Doerr, T; Scripsick, R

    2005-09-23

    This chapter describes procedures for the collection and analysis of samples of various matrices for the purpose of determining the presence of chemical agents in a civilian setting. This appendix is intended to provide the reader with sufficient information to make informed decisions about the sampling and analysis process and to suggest analytical strategies that might be implemented by the scientists performing sampling and analysis. This appendix is not intended to be used as a standard operating procedure to provide detailed instructions as to how trained scientists should handle samples. Chemical agents can be classified by their physical and chemical properties. Table 1 lists the chemical agents considered by this report. In selecting sampling and analysis methods, we have considered procedures proposed by the Organization for Prohibition of Chemical Weapons (OPCW), the U. S. Environmental Protection Agency (EPA), and peer-reviewed scientific literature. EPA analytical methods are good resources describing issues of quality assurance with respect to chain-of-custody, sample handling, and quality control requirements.

  14. Development of an autonomous detector for sensing of nerve agents based on functionalized silicon nanowire field-effect transistors.

    PubMed

    Clavaguera, Simon; Raoul, Nicolas; Carella, Alexandre; Delalande, Michael; Celle, Caroline; Simonato, Jean-Pierre

    2011-10-15

    The ability to detect minute traces of chemical warfare agents is mandatory both for military forces and homeland security. Various detectors based on different technologies are available but still suffer from serious drawbacks such as false positives. There is still a need for the development of innovative reliable sensors, in particular for organophosphorus nerve agents like Sarin. We report herein on the fabrication of a portable, battery-operated, microprocessor-based prototype sensor system relying on silicon nanowire field-effect transistors for the detection of nerve agents. A fast, supersensitive and highly selective detection of organophosphorus molecules is reported. The results show also high selectivity in complex mixtures and on contaminated materials. PMID:21962681

  15. Microwave spectroscopy of chemical warfare agents: prospects for remote sensing

    NASA Astrophysics Data System (ADS)

    Samuels, Alan C.; Jensen, James O.; Suenram, Richard D.; Hight Walker, Angela R.; Woolard, Dwight L.

    1999-07-01

    The high level of interest in the sensor development community in millimeter wave technology development demonstrates the potential for several multipurpose applications of millimeter wave sensors. The potential for remote sensing of hazardous chemical materials based on their millimeter wave rotational signatures is yet another possible applications, offering certain distinct advantages over FTIR remote sensing. The high specificity of the rotational spectra to the molecular structures affords the capability of detecting chemical warfare (CW) agents and degradation products in complex mixtures including water vapor and smoke, an important consideration in military applications. Furthermore, the rotational modes are not complicated by electronic or vibrational transitions, reducing the potential for false alarms. We have conducted microwave spectroscopic measurements on two CW nerve agents (sarin and soman) and one blister agent (H-mustard). The assignment of the observed band furnishes us with an extremely accurate tool for predicting the rotational spectrum of these agents at any arbitrary frequency. By factoring in the effects of pressure (Lorentzian broadening and intensity reduction), we present the predicted spectral signatures of the CW agents in the 80 - 300 GHz region. This frequency regime is important for atmospheric monitoring as it exploits the wide bandwidth capability of millimeter wave sensors as well as the atmospheric windows that occur in this region.

  16. Bubble Jet agent release cartridge for chemical single cell stimulation.

    PubMed

    Wangler, N; Welsche, M; Blazek, M; Blessing, M; Vervliet-Scheebaum, M; Reski, R; Müller, C; Reinecke, H; Steigert, J; Roth, G; Zengerle, R; Paust, N

    2013-02-01

    We present a new method for the distinct specific chemical stimulation of single cells and small cell clusters within their natural environment. By single-drop release of chemical agents with droplets in size of typical cell diameters (d <30 μm) on-demand micro gradients can be generated for the specific manipulation of single cells. A single channel and a double channel agent release cartridge with integrated fluidic structures and integrated agent reservoirs are shown, tested, and compared in this publication. The single channel setup features a fluidic structure fabricated by anisotropic etching of silicon. To allow for simultaneous release of different agents even though maintaining the same device size, the second type comprises a double channel fluidic structure, fabricated by photolithographic patterning of TMMF. Dispensed droplet volumes are V = 15 pl and V = 10 pl for the silicon and the TMMF based setups, respectively. Utilizing the agent release cartridges, the application in biological assays was demonstrated by hormone-stimulated premature bud formation in Physcomitrella patens and the individual staining of one single L 929 cell within a confluent grown cell culture. PMID:22833153

  17. Chemically modified tetracyclines: The novel host modulating agents

    PubMed Central

    Swamy, Devulapalli Narasimha; Sanivarapu, Sahitya; Moogla, Srinivas; Kapalavai, Vasavi

    2015-01-01

    Periodontal pathogens and destructive host responses are involved in the initiation and progression of periodontitis. The emergence of host response modulation as a treatment concept has resulted from our improved understanding of the pathogenesis of periodontal disease. A variety of drugs have been evaluated as host modulation agents (HMA), including Non Steroidal Anti Inflammatory Drugs (NSAIDS), bisphosphonates, tetracyclines, enamel matrix proteins and bone morphogenetic proteins. Chemically modified tetracyclines (CMTs) are one such group of drugs which have been viewed as potential host modulating agents by their anticollagenolytic property. The CMTs are designed to be more potent inhibitors of pro inflammatory mediators and can increase the levels of anti inflammatory mediators. PMID:26392682

  18. Chemically modified tetracyclines: The novel host modulating agents.

    PubMed

    Swamy, Devulapalli Narasimha; Sanivarapu, Sahitya; Moogla, Srinivas; Kapalavai, Vasavi

    2015-01-01

    Periodontal pathogens and destructive host responses are involved in the initiation and progression of periodontitis. The emergence of host response modulation as a treatment concept has resulted from our improved understanding of the pathogenesis of periodontal disease. A variety of drugs have been evaluated as host modulation agents (HMA), including Non Steroidal Anti Inflammatory Drugs (NSAIDS), bisphosphonates, tetracyclines, enamel matrix proteins and bone morphogenetic proteins. Chemically modified tetracyclines (CMTs) are one such group of drugs which have been viewed as potential host modulating agents by their anticollagenolytic property. The CMTs are designed to be more potent inhibitors of pro inflammatory mediators and can increase the levels of anti inflammatory mediators. PMID:26392682

  19. Development of a Persistent Chemical Agent Simulator System (PCASS)

    NASA Technical Reports Server (NTRS)

    Mcginness, W. G.

    1983-01-01

    The development of a persistent chemical agent simulation system (PCASS) is described. This PCASS is to be used for the military training of troops to simulate actual chemical warfare. The purpose of this system is to facilitate in the determination of chemical contamination and effectiveness of decontamination for training purposes. The fluorescent tracer employed has no daylight activation, but yet is easily removed with a decontaminate solution or water and surfactants. Also employed is a time delayed color developing system. When an individual is subjected to the PCASS and does not decontaminate adequately, red blotches or red coloration will develop as a function of time and temperature. The intent of this is to simulate the delayed chemical reaction of mustard contaminates.

  20. Agent-Based Chemical Plume Tracing Using Fluid Dynamics

    NASA Technical Reports Server (NTRS)

    Zarzhitsky, Dimitri; Spears, Diana; Thayer, David; Spears, William

    2004-01-01

    This paper presents a rigorous evaluation of a novel, distributed chemical plume tracing algorithm. The algorithm is a combination of the best aspects of the two most popular predecessors for this task. Furthermore, it is based on solid, formal principles from the field of fluid mechanics. The algorithm is applied by a network of mobile sensing agents (e.g., robots or micro-air vehicles) that sense the ambient fluid velocity and chemical concentration, and calculate derivatives. The algorithm drives the robotic network to the source of the toxic plume, where measures can be taken to disable the source emitter. This work is part of a much larger effort in research and development of a physics-based approach to developing networks of mobile sensing agents for monitoring, tracking, reporting and responding to hazardous conditions.

  1. Tissue-based standoff biosensors for detecting chemical warfare agents

    DOEpatents

    Greenbaum, Elias; Sanders, Charlene A.

    2003-11-18

    A tissue-based, deployable, standoff air quality sensor for detecting the presence of at least one chemical or biological warfare agent, includes: a cell containing entrapped photosynthetic tissue, the cell adapted for analyzing photosynthetic activity of the entrapped photosynthetic tissue; means for introducing an air sample into the cell and contacting the air sample with the entrapped photosynthetic tissue; a fluorometer in operable relationship with the cell for measuring photosynthetic activity of the entrapped photosynthetic tissue; and transmitting means for transmitting analytical data generated by the fluorometer relating to the presence of at least one chemical or biological warfare agent in the air sample, the sensor adapted for deployment into a selected area.

  2. Infrared spectroscopy for chemical agent detection using tailored hypersorbent materials

    NASA Astrophysics Data System (ADS)

    Kozak, Dmitry A.; McGill, R. Andrew; Stievater, Todd H.; Furstenberg, Robert; Pruessner, Marcel W.; Nguyen, Viet

    2015-06-01

    We report long-wave infrared (LWIR, 5-15 μm) and mid-wave infrared (MWIR, 2.5 - 5 μm) differential absorption spectra of different nerve agent simulants and common solutes sorbed to poly(methyldi(1,1,1-trifluoro-2-trifluoromethyl- 2-hydroxypent-4-enyl)silane, HCSFA2, an NRL developed hypersorbent polymer. HCSFA2 is a strong hydrogen-bond acidic polymer which exhibits large gas-polymer partitions for a variety of hazardous chemicals with hydrogen-bond basic properties such as the phosphonate ester G-nerve agents or their simulants. The measured ATR-FTIR differential absorption spectra show complex fingerprint signal changes in the resonances for the sorbent material itself, as well as new resonances arising from chemical bonding between the solute or analyte and the sorbent or the solute itself being present in the sorbent.

  3. Chemical agent detection by surface-enhanced Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Farquharson, Stuart; Gift, Alan; Maksymiuk, Paul; Inscore, Frank E.; Smith, Wayne W.; Morrisey, Kevin; Christesen, Steven D.

    2004-03-01

    In the past decade, the Unites States and its allies have been challenged by a different kind of warfare, exemplified by the terrorist attacks of September 11, 2001. Although suicide bombings are the most often used form of terror, military personnel must consider a wide range of attack scenarios. Among these is the intentional poisoning of water supplies to obstruct military operations in Afghanistan and Iraq. To counter such attacks, the military is developing portable analyzers that can identify and quantify potential chemical agents in water supplies at microgram per liter concentrations within 10 minutes. To aid this effort we have been investigating the value of a surface-enhanced Raman spectroscopy based portable analyzer. In particular we have been developing silver-doped sol-gels to generate SER spectra of chemical agents and their hydrolysis products. Here we present SER spectra of several chemical agents measured in a generic tap water. Repeat measurements were performed to establish statistical error associated with SERS obtained using the sol-gel coated vials.

  4. Passive standoff detection of chemical warfare agents on surfaces.

    PubMed

    Thériault, Jean-Marc; Puckrin, Eldon; Hancock, Jim; Lecavalier, Pierre; Lepage, Carmela Jackson; Jensen, James O

    2004-11-01

    Results are presented on the passive standoff detection and identification of chemical warfare (CW) liquid agents on surfaces by the Fourier-transform IR radiometry. This study was performed during surface contamination trials at Defence Research and Development Canada-Suffield in September 2002. The goal was to verify that passive long-wave IR spectrometric sensors can potentially remotely detect surfaces contaminated with CW agents. The passive sensor, the Compact Atmospheric Sounding Interferometer, was used in the trial to obtain laboratory and field measurements of CW liquid agents, HD and VX. The agents were applied to high-reflectivity surfaces of aluminum, low-reflectivity surfaces of Mylar, and several other materials including an armored personnel carrier. The field measurements were obtained at a standoff distance of 60 m from the target surfaces. Results indicate that liquid contaminant agents deposited on high-reflectivity surfaces can be detected, identified, and possibly quantified with passive sensors. For low-reflectivity surfaces the presence of the contaminants can usually be detected; however, their identification based on simple correlations with the absorption spectrum of the pure contaminant is not possible. PMID:15540446

  5. Passive Standoff Detection of Chemical Warfare Agents on Surfaces

    NASA Astrophysics Data System (ADS)

    Thériault, Jean-Marc; Puckrin, Eldon; Hancock, Jim; Lecavalier, Pierre; Lepage, Carmela Jackson; Jensen, James O.

    2004-11-01

    Results are presented on the passive standoff detection and identification of chemical warfare (CW) liquid agents on surfaces by the Fourier-transform IR radiometry. This study was performed during surface contamination trials at Defence Research and Development Canada-Suffield in September 2002. The goal was to verify that passive long-wave IR spectrometric sensors can potentially remotely detect surfaces contaminated with CW agents. The passive sensor, the Compact Atmospheric Sounding Interferometer, was used in the trial to obtain laboratory and field measurements of CW liquid agents, HD and VX. The agents were applied to high-reflectivity surfaces of aluminum, low-reflectivity surfaces of Mylar, and several other materials including an armored personnel carrier. The field measurements were obtained at a standoff distance of 60 m from the target surfaces. Results indicate that liquid contaminant agents deposited on high-reflectivity surfaces can be detected, identified, and possibly quantified with passive sensors. For low-reflectivity surfaces the presence of the contaminants can usually be detected; however, their identification based on simple correlations with the absorption spectrum of the pure contaminant is not possible.

  6. Chemical Computer Man: Chemical Agent Response Simulation (CARS). Technical report, January 1983-September 1985

    SciTech Connect

    Davis, E.G.; Mioduszewski, R.J.

    1988-03-01

    The Chemical Computer Man: Chemical Agent Response Simulation (CARS) is a computer model and simulation program for estimating the dynamic changes in human physiological dysfunction resulting from exposures to chemical-threat nerve agents. The newly developed CARS methodology simulates agent exposure effects on the following five indices of human physiological function: mental, vision, cardio-respiratory, visceral, and limbs. Mathematical models and the application of basic pharmacokinetic principles were incorporated into the simulation so that for each chemical exposure, the relationship between exposure dosage, absorbed dosage (agent blood plasma concentration), and level of physiological response are computed as a function of time. CARS, as a simulation tool, is designed for the users with little or no computer-related experience. The model combines maximum flexibility with a comprehensive user-friendly interactive menu-driven system. Users define an exposure problem and obtain immediate results displayed in tabular, graphical, and image formats. CARS has broad scientific and engineering applications, not only in technology for the soldier in the area of Chemical Defense, but also in minimizing animal testing in biomedical and toxicological research and the development of a modeling system for human exposure to hazardous-waste chemicals.

  7. An end-to-end approach to developing biological and chemical detector requirements

    NASA Astrophysics Data System (ADS)

    Teclemariam, Nerayo P.; Purvis, Liston K.; Foltz, Greg W.; West, Todd; Edwards, Donna M.; Fruetel, Julia A.; Gleason, Nathaniel J.

    2009-05-01

    Effective defense against chemical and biological threats requires an "end-to-end" strategy that encompasses the entire problem space, from threat assessment and target hardening to response planning and recovery. A key element of the strategy is the definition of appropriate system requirements for surveillance and detection of threat agents. Our end-to-end approach to venue chem/bio defense is captured in the Facilities Weapons of Mass Destruction Decision Analysis Capability (FacDAC), an integrated system-of-systems toolset that can be used to generate requirements across all stages of detector development. For example, in the early stage of detector development the approach can be used to develop performance targets (e.g., sensitivity, selectivity, false positive rate) to provide guidance on what technologies to pursue. In the development phase, after a detector technology has been selected, the approach can aid in determining performance trade-offs and down-selection of competing technologies. During the application stage, the approach can be employed to design optimal defensive architectures that make the best use of available technology to maximize system performance. This presentation will discuss the end-to-end approach to defining detector requirements and demonstrate the capabilities of the FacDAC toolset using examples from a number of studies for the Department of Homeland Security.

  8. The development of immunoassays for detection of chemical warfare agents

    SciTech Connect

    Lenz, D.E.

    1995-06-01

    With the advent of enzyme linked immunoabsorbant assays (ELISA) and monoclonal antibodies in the last two decades, there has been considerable effort devoted to the development of antibodies to detect and quantify low molecular weight toxic substances in environmental or biological fluids. Polyclonal antibodies against paraoxon (the toxic metabolite of parathion) were reported as capable of detecting paraoxon in body fluids at a level of 10{sup -9} M ({approximately}260 pg/mL) when used in a competitive inhibition enzyme immunoassay (CIEIA). Monoclonal antibodies developed against a structural analogue of the chemical warfare agent soman were capable of detecting soman in buffer solutions at a level of 10{sup -6} M ({approximately}180 ng/mL). In addition, these antibodies were highly specific for soman even in the presence of its major hydrolysis product. Subsequent studies with antisoman monoclonal antibodies reported an extension of the level of sensitivity to -80 ng/mL. Furthermore these antibodies did not cross react with other chemical warfare nerve agents such as sarin or tabun. In all cases, the time for a confirmatory test was two hours or less. Immunoassays for T-2 micotoxins have also been reported with a minimal detection range of 2 pg/assay to 50 ng/assay for the polyclonal and monoclonal T-2 antibodies respectively. These antibodies offer a sensitive, rapid and low cost approach to the diagnosis or detection of the presence of toxic chemical substances.

  9. The efficacy of chemical agents in cleaning and disinfection programs

    PubMed Central

    Penna, Thereza Christina Vessoni; Mazzola, Priscila Gava; Silva Martins, Alzira Maria

    2001-01-01

    Background Due to the growing number of outbreaks of infection in hospital nurseries, it becomes essential to set up a sanitation program that indicates that the appropriate chemical agent was chosen for application in the most effective way. Method For the purpose of evaluating the efficacy of a chemical agent, the minimum inhibitory concentration (MIC) was reached by the classic method of successive broth dilutions. The reference bacteria utilized were Bacillus subtilis var. globigii ATCC 9372, Bacillus stearothermophilus ATCC 7953, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923. The strains of Enterobacter cloacae IAL 1976 (Adolfo Lutz Institute), Serratia marcescens IAL 1478 and Acinetobactev calcoaceticus IAL 124 (ATCC 19606), were isolated from material collected from babies involved in outbreaks of infection in hospital nurseries. Results The MIC intervals, which reduced bacteria populations over 08 log10, were: 59 to 156 mg/L of quaternarium ammonium compounds (QACs); 63 to 10000 mg/L of chlorhexidine digluconate; 1375 to 3250 mg/L of glutaraldehyde; 39 to 246 mg/L of formaldehyde; 43750 to 87500 mg/L of isopropanol or ethanol; 1250 to 6250 mg/L of iodine in polyvinyl-pyrolidone complexes, 150 to 4491 mg/L of chlorine-releasing-agents (CRAs); 469 to 2500 mg/L of hydrogen peroxide; and, 2310 to 18500 mg/L of peracetic acid. Conclusions Chlorhexidine showed non inhibitory activity over germinating spores. A. calcoaceticus, was observed to show resistance to the majority of the agents tested, followed by E. cloacae and S. marcescens. PMID:11591223

  10. The development of immunoassays for detection of chemical warfare agents

    SciTech Connect

    Lenz, D.E.; Brimfield, A.A.; Cook, L.

    1996-10-01

    With the advent of enzyme linked immunoabsorbent assays (ELISA) and monoclonal antibodies in the last two decades, there has been considerable effort devoted to the development of antibodies to detect and quantify low molecular weight toxic substances in environmental or biological fluids. Polyclonal antibodies against paraoxon (the toxic metabolite of parathion) were capable of detecting paraoxon in body fluids at a level of 10{sup -9} M ({approximately}260 pg/mL) when used in a competitive inhibition enzyme immunoassay (CIEIA). Monoclonal antibodies developed against a structural analogue of the chemical warfare agent soman were capable of detection soman in buffer solutions at a level of 10{sup -6} M ({approximately}180 ng/mL). In addition these antibodies were found to be highly specific for soman even in the presence of its major hydrolysis product. Subsequent studies with antisoman monoclonal antibodies extended the level of sensitivity to {approximately}80 ng/mL. Furthermore these antibodies did not cross react with other chemical warfare nerve agents such as sarin or tabun. In all cases, the time for a confirmatory test was two hours or less. Immunoassays for T-2 micotoxins have also been reported with a minimal detection range of 2 pg/assay to 50 ng/assay for the polyclonal and monoclonal T-2 antibodies respectively. These reagents offer a sensitive, rapid and low cost approach to the diagnosis or detection of the presence of toxic chemical substances. More recent efforts have focussed on developing antibodies specific for sulfur mustard a highly reactive vesicating agent.

  11. Trend towards low cost, low power, ultra-violet (UV) based biological agent detectors

    NASA Astrophysics Data System (ADS)

    Sickenberger, David

    2005-11-01

    Ultra-violet fluorescence remains a corner stone technique for the detection of biological agent aerosols. Historically, these UV based detectors have employed relatively costly and power demanding lasers that have influenced the exploitation of the technology to wider use. Recent advancements from the Defense Advanced Research Project Agency's (DARPA) Solid-state Ultra Violet Optical Sources (SUVOS) program has changed this. The UV light emitting diode (LED) devices based on Gallium Nitride offer a unique opportunity to produce small, low power, and inexpensive detectors. It may, in fact, be possible to extend the SUVOS technology into detectors that are potentially disposable. This report will present ongoing efforts to explore this possibility. It will present candidate UV fluorescence based detector designs along with the biological aerosol responses obtained from these designs.

  12. Modeling and Visualizing Flow of Chemical Agents Across Complex Terrain

    NASA Technical Reports Server (NTRS)

    Kao, David; Kramer, Marc; Chaderjian, Neal

    2005-01-01

    Release of chemical agents across complex terrain presents a real threat to homeland security. Modeling and visualization tools are being developed that capture flow fluid terrain interaction as well as point dispersal downstream flow paths. These analytic tools when coupled with UAV atmospheric observations provide predictive capabilities to allow for rapid emergency response as well as developing a comprehensive preemptive counter-threat evacuation plan. The visualization tools involve high-end computing and massive parallel processing combined with texture mapping. We demonstrate our approach across a mountainous portion of North California under two contrasting meteorological conditions. Animations depicting flow over this geographical location provide immediate assistance in decision support and crisis management.

  13. Supercritical fluid extraction of chemical warfare agent simulants from soil.

    PubMed

    Griest, W H; Ramsey, R S; Ho, C H; Caldwell, W M

    1992-05-29

    Chemical warfare agent simulants are efficiently recovered from 2-ppm spikes in 1 g of Rocky Mountain Arsenal Standard Soil using methanol-carbon dioxide (5:95) at 300 atm for 2 min at 60 degrees C. Recoveries (n = 3) were 79 +/- 23% for dimethylmethylphosphonate, 93 +/- 14% for 2-chloroethylethyl sulfide, 92 +/- 13% for diisopropylfluorophosphate and 95 +/- 17% for diisopropylmethylphosphonate. Recoveries are higher than, but less precise than those achieved from a 5-min ultrasonic micro-scale extraction using methanol. Much less laboratory waste is generated than the current standard organic solvent extraction method (33 g of soil shaken with 100 ml of chloroform). PMID:1400849

  14. New Chemically Functionalized Nanomaterials for Electrical Nerve Agents Sensors

    NASA Astrophysics Data System (ADS)

    Simonato, Jean-Pierre; Clavaguera, Simon; Carella, Alexandre; Delalande, Michael; Raoul, Nicolas; Lenfant, Stephane; Vuillaume, Dominique; Dubois, Emmanuel

    2011-08-01

    A chemical receptor specific to traces of organophosphorus nerve agents (OPs) has been synthesized and grafted to carbon nanotubes and silicon nanowires in order to make electrical sensors. Our results show that it is possible to detect efficiently sub-ppm traces of OPs with excellent selectivity notably with the use of silicon nanowires by monitoring the Drain-Source current of the SiNW-FET at an optimum back Gate voltage as a function of time. First developments of a prototype have also been realized.

  15. 28 CFR 552.25 - Use of less-than-lethal weapons, including chemical agents.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., including chemical agents. 552.25 Section 552.25 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF... Use of less-than-lethal weapons, including chemical agents. (a) The Warden may authorize the use of less-than-lethal weapons, including those containing chemical agents, only when the situation is...

  16. 28 CFR 552.25 - Use of chemical agents or non-lethal weapons.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Use of chemical agents or non-lethal... INSTITUTIONAL MANAGEMENT CUSTODY Use of Force and Application of Restraints on Inmates § 552.25 Use of chemical agents or non-lethal weapons. The Warden may authorize the use of chemical agents or non-lethal...

  17. 28 CFR 552.25 - Use of less-than-lethal weapons, including chemical agents.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., including chemical agents. 552.25 Section 552.25 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF... Use of less-than-lethal weapons, including chemical agents. (a) The Warden may authorize the use of less-than-lethal weapons, including those containing chemical agents, only when the situation is...

  18. 28 CFR 552.25 - Use of less-than-lethal weapons, including chemical agents.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., including chemical agents. 552.25 Section 552.25 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF... Use of less-than-lethal weapons, including chemical agents. (a) The Warden may authorize the use of less-than-lethal weapons, including those containing chemical agents, only when the situation is...

  19. 28 CFR 552.25 - Use of less-than-lethal weapons, including chemical agents.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., including chemical agents. 552.25 Section 552.25 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF... Use of less-than-lethal weapons, including chemical agents. (a) The Warden may authorize the use of less-than-lethal weapons, including those containing chemical agents, only when the situation is...

  20. Management of Root Resorption Using Chemical Agents: A Review.

    PubMed

    Mohammadi, Zahed; C Cehreli, Zafer; Shalavi, Sousan; Giardino, Luciano; Palazzi, Flavio; Asgary, Saeed

    2016-01-01

    Root resorption (RR) is defined as the loss of dental hard tissues because of clastic activity inside or outside of tooth the root. In the permanent dentition, RR is a pathologic event; if untreated, it might result in the premature loss of the affected tooth. Several hypotheses have been suggested as the mechanisms of root resorption such as absence of the remnants of Hertwig's epithelial root sheath (HERS) and the absence of some intrinsic factors in cementum and predentin such as amelogenin or osteoprotegerin (OPG). It seems that a barrier is formed by the less-calcified intermediate cementum or the cementodentin junction that prevents external RR. There are several chemical strategies to manage root resorption. The purpose of this paper was to review several chemical agents to manage RR such as tetracycline, sodium hypochlorite, acids (citric acid, phosphoric acid, ascorbic acid and hydrochloric acid), acetazolamide, calcitonin, alendronate, fluoride, Ledermix and Emdogain. PMID:26843869

  1. Hand-Held Devices Detect Explosives and Chemical Agents

    NASA Technical Reports Server (NTRS)

    2010-01-01

    Ion Applications Inc., of West Palm Beach, Florida, partnered with Ames Research Center through Small Business Innovation Research (SBIR) agreements to develop a miniature version ion mobility spectrometer (IMS). While NASA was interested in the instrument for detecting chemicals during exploration of distant planets, moons, and comets, the company has incorporated the technology into a commercial hand-held IMS device for use by the military and other public safety organizations. Capable of detecting and identifying molecules with part-per-billion sensitivity, the technology now provides soldiers with portable explosives and chemical warfare agent detection. The device is also being adapted for detecting drugs and is employed in industrial processes such as semiconductor manufacturing.

  2. Evaluation of SERS substrates for chemical agent detection

    NASA Astrophysics Data System (ADS)

    Huang, Hermes; Shende, Chetan; Sengupta, Atanu; Inscore, Frank; Farquharson, Stuart

    2012-06-01

    US Military forces are dependent on indigenous water supplies, which are considered prime targets to effect a chemical or biological attack. Consequently, there is a clear need for a portable analyzer capable of evaluating water supplies prior to use. To this end we have been investigating the use of a portable Raman analyzer with surface-enhanced Raman spectroscopy (SERS) sampling systems. The superior selectivity and exceptional sensitivity of SERS has been demonstrated by the detection of single molecules. However, the extreme sensitivity provided by SERS is attributed to "hot spot" structures, such as particle junctions that can provide as much as 10 orders of magnitude enhancement. Unfortunately, hotspots are not evenly distributed across substrates, which results in enhancements that cannot be quantitatively reproduced. Here we present analysis of uniformity for a newly developed substrate and commercial sample vials using benzenethiol and bispyridylethylene, two chemicals often used to characterize SERS substrates, and methyl phosphonic acid, a major hydrolysis product of the nerve agents.

  3. Management of Root Resorption Using Chemical Agents: A Review

    PubMed Central

    Mohammadi, Zahed; C. Cehreli, Zafer; Shalavi, Sousan; Giardino, Luciano; Palazzi, Flavio; Asgary, Saeed

    2016-01-01

    Root resorption (RR) is defined as the loss of dental hard tissues because of clastic activity inside or outside of tooth the root. In the permanent dentition, RR is a pathologic event; if untreated, it might result in the premature loss of the affected tooth. Several hypotheses have been suggested as the mechanisms of root resorption such as absence of the remnants of Hertwig's epithelial root sheath (HERS) and the absence of some intrinsic factors in cementum and predentin such as amelogenin or osteoprotegerin (OPG). It seems that a barrier is formed by the less-calcified intermediate cementum or the cementodentin junction that prevents external RR. There are several chemical strategies to manage root resorption. The purpose of this paper was to review several chemical agents to manage RR such as tetracycline, sodium hypochlorite, acids (citric acid, phosphoric acid, ascorbic acid and hydrochloric acid), acetazolamide, calcitonin, alendronate, fluoride, Ledermix and Emdogain. PMID:26843869

  4. Ocular scanning instrumentation: rapid diagnosis of chemical threat agent exposure

    NASA Astrophysics Data System (ADS)

    Molnar, Lance R.; Odom, J. V.; DeRoos, Bradley G.; Kolanko, Christopher J.

    2004-09-01

    Military personnel and first responders are in critical need of a sensitive technology for the rapid evaluation and diagnosis of exposure to adverse chemical agents. Ideally such a technology would be automated, easily portable, possess a high degree of sensitivity and specificity, and provide non-invasive assessment of health status. A potential method for meeting these requirements is via monitoring of ocular characteristics. Due to the interconnection between the eyes and the various physiological systems of the body, insults to the body may create a unique "thumbprint" upon the eyes based upon how these various physiological systems are differentially affected. In turn, these thumbprints (biomarkers) may be used to perform diagnostic evaluations of an individual"s health status. Based upon this principle, the Ocular Scanning Instrumentation (OSI) technology is being developed as an automated device for non-invasive monitoring of optically apparent characteristics and attributes of the eyes for in-the-field diagnosis of battlefield traumas, insults, and threat agent exposures. The current manuscript presents comparative data for two of the agents which we have evaluated, carbon monoxide and cyanide. The defined methods provide the required specificity and sensitivity needed for detecting exposures at time points which provide an ample therapeutic window for medical intervention.

  5. Tear gas--harassing agent or toxic chemical weapon

    SciTech Connect

    Hu, H.; Fine, J.; Epstein, P.; Kelsey, K.; Reynolds, P.; Walker, B.

    1989-08-04

    Tear gas has gained widespread acceptance as a means of controlling civilian crowds and subduing barricaded criminals. The most widely used forms of tear gas have been o-chlorobenzylidenemalononitrile and omega-chloroacetophenone. Proponents of their use claim that, if used correctly, the noxious effects of exposure are transient and of no long-term consequences. The use of tear gas in recent situations of civil unrest, however, demonstrates that exposure to the weapon is difficult to control and indiscriminate, and the weapon is often not used correctly. Severe traumatic injury from exploding tear gas bombs as well as lethal toxic injury have been documented. Moreover, available toxicological data are deficient as to the potential of tear gas agents to cause long-term pulmonary, carcinogenic, and reproductive effects. Published and recent unpublished in vitro tests have shown o-chlorobenzylidenemalononitrile to be both clastogenic and mutagenic. Sadly, the nature of its use renders analytic epidemiologic investigation of exposed persons difficult. In 1969, eighty countries voted to include tear gas agents among chemical weapons banned under the Geneva Protocol. There is an ongoing need for investigation into the full toxicological potential of tear gas chemicals and renewed debate on whether their use can be condoned under any circumstances. 48 references.

  6. μ-PADs for detection of chemical warfare agents.

    PubMed

    Pardasani, Deepak; Tak, Vijay; Purohit, Ajay K; Dubey, D K

    2012-12-01

    Conventional methods of detection of chemical warfare agents (CWAs) based on chromogenic reactions are time and solvent intensive. The development of cost, time and solvent effective microfluidic paper based analytical devices (μ-PADs) for the detection of nerve and vesicant agents is described. The detection of analytes was based upon their reactions with rhodamine hydroxamate and para-nitrobenzyl pyridine, producing red and blue colours respectively. Reactions were optimized on the μ-PADs to produce the limits of detection (LODs) as low as 100 μM for sulfur mustard in aqueous samples. Results were quantified with the help of a simple desktop scanner and Photoshop software. Sarin achieved a linear response in the two concentration ranges of 20-100 mM and 100-500 mM, whereas the response of sulfur mustard was found to be linear in the concentration range of 10-75 mM. Results were precise enough to establish the μ-PADs as a valuable tool for security personnel fighting against chemical terrorism. PMID:23086107

  7. Sensitive detection of chemical agents and toxic industrial chemicals using active open-path FTIRs

    NASA Astrophysics Data System (ADS)

    Walter, William T.

    2004-03-01

    Active open-path FTIR sensors provide more sensitive detection of chemical agents than passive FTIRs, such as the M21 RSCAAL and JSLSCAD, and at the same time identify and quantify toxic industrial chemicals (TIC). Passive FTIRs are bistatic sensors relying on infrared sources of opportunity. Utilization of earth-based sources of opportunity limits the source temperatures available for passive chemical-agent FTIR sensors to 300° K. Active FTIR chemical-agent sensors utilize silicon carbide sources, which can be operated at 1500° K. The higher source temperature provides more than an 80-times increase in the infrared radiant flux emitted per unit area in the 7 to 14 micron spectral fingerprint region. Minimum detection limits are better than 5 μgm/m3 for GA, GB, GD, GF and VX. Active FTIR sensors can (1) assist first responders and emergency response teams in their assessment of and reaction to a terrorist threat, (2) provide information on the identification of the TIC present and their concentrations and (3) contribute to the understanding and prevention of debilitating disorders analogous to the Gulf War Syndrome for military and civilian personnel.

  8. Nanostructured Metal Oxides for Stoichiometric Degradation of Chemical Warfare Agents.

    PubMed

    Štengl, Václav; Henych, Jiří; Janoš, Pavel; Skoumal, Miroslav

    2016-01-01

    Metal oxides have very important applications in many areas of chemistry, physics and materials science; their properties are dependent on the method of preparation, the morphology and texture. Nanostructured metal oxides can exhibit unique characteristics unlike those of the bulk form depending on their morphology, with a high density of edges, corners and defect surfaces. In recent years, methods have been developed for the preparation of metal oxide powders with tunable control of the primary particle size as well as of a secondary particle size: the size of agglomerates of crystallites. One of the many ways to take advantage of unique properties of nanostructured oxide materials is stoichiometric degradation of chemical warfare agents (CWAs) and volatile organic compounds (VOC) pollutants on their surfaces. PMID:26423076

  9. Anti-ulcer agents: chemical aspect of solving the problem

    NASA Astrophysics Data System (ADS)

    Rogoza, L. N.; Salakhutdinov, N. F.

    2015-01-01

    The data on chemical structures and specific activities of compounds functioning as histamine H2-receptor antagonists, H+/K+-ATPase inhibitors at the exchange sites of hydrogen ions (proton pump inhibitors) and potassium ions (K+-competitive acid blockers) published from 1990 to 2013 are surveyed. The antisecretory agents with studied cytoprotective activity or with additional therapeutic properties compensating for disorders of internal defence mechanisms are presented. A separate section is devoted to the drugs that prevent or mitigate the NSAID-induced intestinal damage. All of the considered structures are classified according to the type of biological mechanism of action. Some aspects of the structure-activity relationships for such compounds are considered. The bibliography includes 83 references.

  10. Single crystal diamond detectors grown by chemical vapor deposition

    NASA Astrophysics Data System (ADS)

    Tuvè, C.; Angelone, M.; Bellini, V.; Balducci, A.; Donato, M. G.; Faggio, G.; Marinelli, M.; Messina, G.; Milani, E.; Morgada, M. E.; Pillon, M.; Potenza, R.; Pucella, G.; Russo, G.; Santangelo, S.; Scoccia, M.; Sutera, C.; Tucciarone, A.; Verona-Rinati, G.

    2007-01-01

    The detection properties of heteropitaxial (polycrystalline, pCVD) and homoepitaxial (single crystal, scCVD) diamond films grown by microwave chemical vapor deposition (CVD) in the Laboratories of Roma "Tor Vergata" University are reported. The pCVD diamond detectors were tested with α-particles from different sources and 12C ions produced by 15 MV Tandem accelerator at Southern National Laboratories (LNS) in Catania (Italy). pCVDs were also used to monitor 14 MeV neutrons produced by the D-T plasma at Joint European Torus (JET), Culham, U.K. The limit of pCVDs is the poor energy resolution. To overcome this problem, we developed scCVD diamonds using the same reactor parameters that optimized pCVD diamonds. scCVD were grown on a low cost (1 0 0) HPHT single crystal substrate. A detector 110 μm thick was tested under α-particles and under 14 MeV neutron irradiation. The charge collection efficiency spectrum measured under irradiation with a triple α-particle source shows three clearly resolved peaks, with an energy resolution of about 1.1%. The measured spectra under neutron irradiation show a well separated C(n,α0)9Be12 reaction peak with an energy spread of 0.5 MeV for 14.8 MeV neutrons and 0.3 MeV for 14.1 MeV neutrons, which are fully compatible with the energy spread of the incident neutron beams.

  11. Toxicology and pharmacology of the chemical warfare agent sulfur mustard.

    PubMed

    Dacre, J C; Goldman, M

    1996-06-01

    There have been reports of chemical attacks in which sulfur mustard might have been used (a) on Iranian soldiers and civilians during the Gulf War in 1984 and 1985 and (b) in an Iraqi chemical attack on the Iranian-occupied village of Halbja in 1988, resulting in many civilian casualties. Heavy use of chemical warfare in Afghanistan by the Soviet military is a recent innovation in military tactics that has been highly successful and may ensure further use of chemical agents in future military conflicts and terrorist attacks as a profitable adjunct to conventional military arms. Mustard is a poisonous chemical agent that exerts a local action on the eyes, skin, and respiratory tissue, with subsequent systemic action on the nervous, cardiac, and digestive systems in humans and laboratory animals, causing lacrimation, malaise, anorexia, salivation, respiratory distress, vomiting, hyperexcitability, and cardiac distress. Under extreme circumstances, dependent upon the dose and length of exposure to the agent, necrosis of the skin and mucous membranes of the respiratory system, bronchitis, bronchopneumonia, intestinal lesions, hemoconcentration, leucopenia, convulsions with systemic distress, and death occur. Severe mustard poisoning in humans is associated with systemic injury, which is manifested as headache, epigastric distresses, anorexia, diarrhea, and cachexia and is usually observed at mustard doses of 1000 mg/min/m3 with damage to hematopoietic tissues and progressive leucopenia. Sulfur mustard is a cell poison that causes disruption and impairment of a variety of cellular activities that are dependent upon a very specific integral relationship. These cytotoxic effects are manifested in widespread metabolic disturbances whose variable characteristics are observed in enzymatic deficiencies, vesicant action, abnormal mitotic activity and cell division, bone marrow disruption, disturbances in hematopoietic activity, and systemic poisoning. Indeed, mustard gas

  12. Detection of Chemical/Biological Agents and Stimulants using Quadrupole Ion Trap Mass Spectrometry

    SciTech Connect

    Harmon, S.H.; Hart, K.J.; Vass, A.A.; Wise, M.B.; Wolf, D.A.

    1999-06-14

    Detection of Chemical/Biological Agents and Simulants A new detector for chemical and biological agents is being developed for the U. S. Army under the Chemical and Biological Mass Spectrometer Block II program. The CBMS Block II is designed to optimize detection of both chemical and biological agents through the use of direct sampling inlets [I], a multi- ported sampling valve and a turbo- based vacuum system to support chemical ionization. Unit mass resolution using air as the buffer gas [2] has been obtained using this design. Software to control the instrument and to analyze the data generated from the instrument has also been newly developed. Detection of chemical agents can be accomplished. using the CBMS Block II design via one of two inlets - a l/ I 6'' stainless steel sample line -Chemical Warfare Air (CW Air) or a ground probe with enclosed capillary currently in use by the US Army - CW Ground. The Block II design is capable of both electron ionization and chemical ionization. Ethanol is being used as the Cl reagent based on a study indicating best performance for the Biological Warfare (BW) detection task (31). Data showing good signal to noise for 500 pg of methyl salicylate injected into the CW Air inlet, 50 ng of dimethylmethylphosphonate exposed to the CW Ground probe and 5 ng of methyl stearate analyzed using the pyrolyzer inlet were presented. Biological agents are sampled using a ''bio-concentrator'' unit that is designed to concentrate particles in the low micron range. Particles are collected in the bottom of a quartz pyrolyzer tube. An automated injector is being developed to deliver approximately 2 pL of a methylating reagent, tetramethylamonium- hydroxide to 'the collected particles. Pyrolysis occurs by rapid heating to ca. 55OOC. Biological agents are then characterized by their fatty acid methyl ester profiles and by other biomarkers. A library of ETOH- Cl/ pyrolysis MS data of microorganisms used for a recently published study [3] has been

  13. Reduced chemical warfare agent sorption in polyurethane-painted surfaces via plasma-enhanced chemical vapor deposition of perfluoroalkanes.

    PubMed

    Gordon, Wesley O; Peterson, Gregory W; Durke, Erin M

    2015-04-01

    Perfluoralkalation via plasma chemical vapor deposition has been used to improve hydrophobicity of surfaces. We have investigated this technique to improve the resistance of commercial polyurethane coatings to chemicals, such as chemical warfare agents. The reported results indicate the surface treatment minimizes the spread of agent droplets and the sorption of agent into the coating. The improvement in resistance is likely due to reduction of the coating's surface free energy via fluorine incorporation, but may also have contributing effects from surface morphology changes. The data indicates that plasma-based surface modifications may have utility in improving chemical resistance of commercial coatings. PMID:25775244

  14. Antioxidants as potential medical countermeasures for chemical warfare agents and toxic industrial chemicals.

    PubMed

    McElroy, Cameron S; Day, Brian J

    2016-01-15

    The continuing horrors of military conflicts and terrorism often involve the use of chemical warfare agents (CWAs) and toxic industrial chemicals (TICs). Many CWA and TIC exposures are difficult to treat due to the danger they pose to first responders and their rapid onset that can produce death shortly after exposure. While the specific mechanism(s) of toxicity of these agents are diverse, many are associated either directly or indirectly with increased oxidative stress in affected tissues. This has led to the exploration of various antioxidants as potential medical countermeasures for CWA/TIC exposures. Studies have been performed across a wide array of agents, model organisms, exposure systems, and antioxidants, looking at an almost equally diverse set of endpoints. Attempts at treating CWAs/TICs with antioxidants have met with mixed results, ranging from no effect to nearly complete protection. The aim of this commentary is to summarize the literature in each category for evidence of oxidative stress and antioxidant efficacy against CWAs and TICs. While there is great disparity in the data concerning methods, models, and remedies, the outlook on antioxidants as medical countermeasures for CWA/TIC management appears promising. PMID:26476351

  15. Mid-wave infrared hyperspectral imaging of unknown chemical warfare agents

    NASA Astrophysics Data System (ADS)

    Clewes, Rhea J.; Howle, Chris R.; Guicheteau, Jason; Emge, Darren; Ruxton, Keith; Robertson, Gordon; Miller, William; Malcolm, Graeme; Maker, Gareth T.

    2013-05-01

    The ability of a stand-off chemical detector to distinguish two different chemical warfare agents is demonstrated in this paper. Using Negative Contrast Imaging, based upon IR absorption spectroscopy, we were able to detect 1 μl of VX, sulfur mustard and water on a subset of representative surfaces. These experiments were performed at a range of 1.3 metres and an angle of 45° to the surface. The technique employed utilises a Q-switched intracavity MgO:PPLN crystal that generated 1.4 - 1.8 μm (shortwave) and 2.6 - 3.6 μm (midwave) infrared radiation (SWIR and MWIR, respectively). The MgO:PPLN crystal has a fanned grating design which, via translation through a 1064 nm pump beam, enables tuning through the SWIR and MWIR wavelength ranges. The SWIR and MWIR beams are guided across a scene via a pair of raster scanned mirrors allowing detection of absorption features within these spectral regions. This investigation exploited MWIR signatures, as they provided sufficient molecular information to distinguish between toxic and benign chemicals in these proof-of-concept experiments.

  16. The use of a photoionization detector to detect harmful volatile chemicals by emergency personnel

    PubMed Central

    Patel, Neil D; Fales, William D; Farrell, Robert N

    2009-01-01

    Objective The objective of this investigation was to determine if a photoionization detector (PID) could be used to detect the presence of a simulated harmful chemical on simulated casualties of a chemical release. Methods A screening protocol, based on existing radiation screening protocols, was developed for the purposes of the investigation. Three simulated casualties were contaminated with a simulated chemical agent and two groups of emergency responders were involved in the trials. The success–failure ratio of the participants was used to judge the performance of the PID in this application. Results A high success rate was observed when the screening protocol was properly adhered to (97.67%). Conversely, the success rate suffered when participants deviated from the protocol (86.31%). With one exception, all failures were noted to have been the result of a failure to correctly observe the established screening protocol. Conclusions The results of this investigation indicate that the PID may be an effective screening tool for emergency responders. However, additional study is necessary to both confirm the effectiveness of the PID and refine the screening protocol if necessary. PMID:27147829

  17. Non-cancer effects of chemical agents on children's health.

    PubMed

    Röösli, Martin

    2011-12-01

    This paper provides an overview about the non-cancer health effects for children from relevant chemical agents in our environment. In addition, a meta-analysis was conducted on the association between sudden infant death syndrome (SIDS) and maternal smoking during pregnancy as well as postnatal exposure to environmental tobacco smoke (ETS). In children, birth deformities, neurodevelopment, reproductive outcomes and respiratory system are mainly affected by chemical exposures. According to recent systematic reviews, evidence is sufficient for cognitive impairments caused by low lead exposure levels. Evidence for neurotoxicity from prenatal methylmercury exposure is sufficient for high exposure levels and limited for low levels. Prenatal exposure to polychlorinated biphenyls (PCB) and related toxicants results in cognitive and motor deficits. Maternal smoking during pregnancy is a risk factor for preterm birth, foetal growth deficit and SIDS. The meta-analytic pooled risk estimate for SIDS based on 15 studies is 2.94 (95% confidence interval: 2.43-3.57). Postnatal exposure to ETS was found to increase the SIDS risk by a factor of 1.72 (95% CI: 1.28-2.30) based on six studies which took into account maternal smoking during pregnancy. Additionally, postnatal ETS exposure causes acute respiratory infections, ear problems, respiratory symptoms, more severe asthma, and it slows lung growth. These health effects are also of concern for postnatal exposure to ambient and indoor air pollution. Children differ from adults with respect to several aspects which are relevant for assessing their health risk. Thus, independent evaluation of toxicity in childhood populations is essential. PMID:21906619

  18. Human scalp permeability to the chemical warfare agent VX.

    PubMed

    Rolland, P; Bolzinger, M-A; Cruz, C; Briançon, S; Josse, D

    2011-12-01

    The use of chemical warfare agents such as VX in terrorism act might lead to contamination of the civilian population. Human scalp decontamination may require appropriate products and procedures. Due to ethical reasons, skin decontamination studies usually involve in vitro skin models, but human scalp skin samples are uncommon and expensive. The purpose of this study was to characterize the in vitro permeability to VX of human scalp, and to compare it with (a) human abdominal skin, and (b) pig skin from two different anatomic sites: ear and skull roof, in order to design a relevant model. Based on the VX skin permeation kinetics and distribution, we demonstrated that (a) human scalp was significantly more permeable to VX than abdominal skin and (b) pig-ear skin was the most relevant model to predict the in vitro human scalp permeability. Our results indicated that the follicular pathway significantly contributed to the skin absorption of VX through human scalp. In addition, the hair follicles and the stratum corneum significantly contributed to the formation of a skin reservoir for VX. PMID:21762776

  19. Liquid contents verification for explosives, chemical agents, and dissolved narcotics

    NASA Astrophysics Data System (ADS)

    Kumar, Sankaran; McMichael, W. Casey; Magnuson, Erik E.; Lee, Young K.; Moeller, Charles R.; Czipott, Peter V.; Rayner, Timothy J.; Newman, David E.; Wroblewski, Dariusz

    2001-02-01

    An increasingly important need today is to guard against terrorist attacks at key locations such as airports and public buildings. Liquid explosives can avoid detection at security checkpoints by being concealed as beverages or other benign liquids. Magnetic resonance (MR) offers a safe, non-invasive technology for probing and classifying the liquid contents inside sealed non-metallic containers or packages. Quantum Magnetics has developed a Liquid Explosives Screening System or `Bottle Scanner' to screen for liquid explosives and flammables, described at an earlier SPIE conference in 1996. Since then, the Bottle Scanner's performance has been significantly improved by the incorporation of neural network-based liquid classification. Recently we have shown that the incorporation of additional discrimination parameters can further enhance liquid classification. In addition to screening for explosives and flammables, the Bottle Scanner can be effective against chemical agents, many of which contain fluorine or phosphorous, both of which have MR signatures. Finally, we have evidence that the Bottle Scanner may also be able to detect narcotics dissolved in beverages, one of the methods used to smuggle narcotics across international borders. The development of the Bottle Scanner has been funded by the Federal Aviation Administration.

  20. Studies on residue-free decontaminants for chemical warfare agents.

    PubMed

    Wagner, George W

    2015-03-17

    Residue-free decontaminants based on hydrogen peroxide, which decomposes to water and oxygen in the environment, are examined as decontaminants for chemical warfare agents (CWA). For the apparent special case of CWA on concrete, H2O2 alone, without any additives, effectively decontaminates S-2-(diisopropylamino)ethyl O-ethyl methylphosphonothioate (VX), pinacolyl methylphosphorofluoridate (GD), and bis(2-choroethyl) sulfide (HD) in a process thought to involve H2O2 activation by surface-bound carbonates/bicarbonates (known H2O2 activators for CWA decontamination). A plethora of products are formed during the H2O2 decontamination of HD on concrete, and these are characterized by comparison to synthesized authentic compounds. As a potential residue-free decontaminant for surfaces other than concrete (or those lacking adsorbed carbonate/bicarbonate) H2O2 activation for CWA decontamination is feasible using residue-free NH3 and CO2 as demonstrated by reaction studies for VX, GD, and HD in homogeneous solution. Although H2O2/NH3/CO2 ("HPAC") decontaminants are active for CWA decontamination in solution, they require testing on actual surfaces of interest to assess their true efficacy for surface decontamination. PMID:25710477

  1. TOXICITY-BASED CHEMICAL AGENT DETECTION SYSTEMS: CONTINUOUS MONITOR AND EXPOSURE HISTORY

    EPA Science Inventory

    This project will develop and characterize chemical agent detection systems that will provide broad toxicological screening information to first responders and building decontamination personnel. The primary goal for this technology is to detect the presence of airborne chemic...

  2. Experimental Simulations for Elimination of Biological and/or Chemical Agents

    NASA Astrophysics Data System (ADS)

    Hong, Yong C.; Kim, Jeong H.; Uhm, Han S.

    2003-10-01

    The threat of biological and/or chemical agents in a domestic terrorist attack and in military conflict is increasing worldwide. The 2oo1 anthrax terror throughout the USA, 1995 sarin nerve gas attack on Tokyo subway, and the like are evident for this threat. Elimination and decontamination of biological and/or chemical agents are needed for such an attack. Experimental simulation for elimination of biological and/or chemical agents using an atmospheric-pressure microwave plasma torch is carried out. The elimination of biological and/or chemical agents through the vitrification or burnout of sewage sludge powders and the decomposition of toluene gas as a chemical agent stimulant is presented. A detailed characterization for the elimination of the simulant chemicals using Fourier Transform Infrared (FT-IR) and Gas Chromatography (GC) is also presented.

  3. Optical detection of chemical warfare agents and toxic industrial chemicals: Simulation

    NASA Astrophysics Data System (ADS)

    Webber, Michael E.; Pushkarsky, Michael; Patel, C. Kumar N.

    2005-06-01

    We present an analysis of optical techniques for the detection of chemical warfare agents and toxic industrial chemicals in real-world conditions. We analyze the problem of detecting a target species in the presence of a multitude of interferences that are often stochastic and we provide a broadly applicable technique for evaluating the sensitivity, probability of false positives (PFP), and probability of false negatives (PFN) for a sensor through the illustrative example of a laser photoacoustic spectrometer (L-PAS). This methodology includes (1) a model of real-world air composition, (2) an analytical model of an actual field-deployed L-PAS, (3) stochasticity in instrument response and air composition, (4) repeated detection calculations to obtain statistics and receiver operating characteristic curves, and (5) analyzing these statistics to determine the sensor's sensitivity, PFP, and PFN. This methodology was used to analyze variations in sensor design and ambient conditions, and can be utilized as a framework for comparing different sensors.

  4. Rapid Ultrasensitive Chemical-Fingerprint Detection of Chemical and Biochemical Warfare Agents

    SciTech Connect

    ASHBY, CAROL I.; SHEPODD, TIMOTHY J.; YELTON, WILLIAM G.; MURON, DAVID J.

    2002-12-01

    Vibrational spectra can serve as chemical fingerprints for positive identification of chemical and biological warfare molecules. The required speed and sensitivity might be achieved with surface-enhanced Raman spectroscopy (SERS) using nanotextured metal surfaces. Systematic and reproducible methods for preparing metallic surfaces that maximize sensitivity have not been previously developed. This work sought to develop methods for forming high-efficiency metallic nanostructures that can be integrated with either gas or liquid-phase chem-lab-on-a-chip separation columns to provide a highly sensitive, highly selective microanalytical system for detecting current and future chem/bio agents. In addition, improved protein microchromatographic systems have been made by the creation of acrylate-based porous polymer monoliths that can serve as protein preconcentrators to reduce the optical system sensitivity required to detect and identify a particular protein, such as a bacterial toxin.

  5. Stand-off tissue-based biosensors for the detection of chemical warfare agents using photosynthetic fluorescence induction.

    PubMed

    Sanders, C A; Rodriguez, M; Greenbaum, E

    2001-09-01

    Tissue biosensors made from immobilized whole-cell photosynthetic microorganisms have been developed for the detection of airborne chemical warfare agents and simulants. The sensor read-out is based on well-known principles of fluorescence induction by living photosynthetic tissue. Like the cyanobacteria and algae from which they were constructed, the sensors are robust and mobile. The fluorescence signal from the sensors was stable after 40 days, storage and they can be launched or dropped into suspected danger zones. Commercially available hand-held fluorometric detector systems were used to measure Photosystem II (PSII) photochemical efficiency of green algae and cyanobacteria entrapped on filter paper disks. Toxic agents flowing in the gas stream through the sensors can alter the characteristic fluorescence induction curves with resultant changes in photochemical yields. Tabun (GA), sarin (GB), mustard agent, tributylamine (TBA) (a sarin stabilizer), and dibutyl sulfide (DBS) (a mustard agent analog) were tested. Upper threshold limits of detectability for GA, TBA, and DBS are reported. With additional research and development, these biosensors may find application in stand-off detection of chemical and perhaps biological warfare agents under real-world conditions. PMID:11544038

  6. Technological advancements for the detection of and protection against biological and chemical warfare agents.

    PubMed

    Eubanks, Lisa M; Dickerson, Tobin J; Janda, Kim D

    2007-03-01

    There is a growing need for technological advancements to combat agents of chemical and biological warfare, particularly in the context of the deliberate use of a chemical and/or biological warfare agent by a terrorist organization. In this tutorial review, we describe methods that have been developed both for the specific detection of biological and chemical warfare agents in a field setting, as well as potential therapeutic approaches for treating exposure to these toxic species. In particular, nerve agents are described as a typical chemical warfare agent, and the two potent biothreat agents, anthrax and botulinum neurotoxin, are used as illustrative examples of potent weapons for which countermeasures are urgently needed. PMID:17325785

  7. Chemical imaging of cotton fibers using an infrared microscope and a focal-plane array detector

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this presentation, the chemical imaging of cotton fibers with an infrared microscope and a Focal-Plane Array (FPA) detector will be discussed. Infrared spectroscopy can provide us with information on the structure and quality of cotton fibers. In addition, FPA detectors allow for simultaneous spe...

  8. Statistical models for LWIR hyperspectral backgrounds and their applications in chemical agent detection

    NASA Astrophysics Data System (ADS)

    Manolakis, D.; Jairam, L. G.; Zhang, D.; Rossacci, M.

    2007-04-01

    Remote detection of chemical vapors in the atmosphere has a wide range of civilian and military applications. In the past few years there has been significant interest in the detection of effluent plumes using hyperspectral imaging spectroscopy in the 8-13μm atmospheric window. A major obstacle in the full exploitation of this technology is the fact that everything in the infrared is a source of radiation. As a result, the emission from the gases of interest is always mixed with emission by the more abundant atmospheric constituents and by other objects in the sensor field of view. The radiance fluctuations in this background emission constitute an additional source of interference which is much stronger than the detector noise. In this paper we develop and evaluate parametric models for the statistical characterization of LWIR hyperspectral backgrounds. We consider models based on the theory of elliptically contoured distributions. Both models can handle heavy tails, which is a key stastical feature of hyperspectral imaging backgrounds. The paper provides a concise description of the underlying models, the algorithms used to estimate their parameters from the background spectral measurements, and the use of the developed models in the design and evaluation of chemical warfare agent detection algorithms.

  9. Estimated Chemical Warfare Agent Surface Clearance Goals for Remediation Pre-Planning

    SciTech Connect

    Dolislager, Frederick; Bansleben, Dr. Donald; Watson, Annetta Paule

    2010-01-01

    Health-based surface clearance goals, in units of mg/cm2, have been developed for the persistent chemical warfare agents sulfur mustard (HD) and nerve agent VX as well as their principal degradation products. Selection of model parameters and critical receptor (toddler child) allow calculation of surface residue estimates protective for the toddler child, the general population and adult employees of a facilty that has undergone chemical warfare agent attack.

  10. Structure-activity predictions of properties of organophosphorus pesticides and chemical agents important for optical detection. Master`s thesis

    SciTech Connect

    Porte, R.E.

    1995-12-01

    This thesis presents the results of an investigation for estimating various physicochemical properties of chemical warfare agents and organophosphorus pesticides. The determination of aqueous solubility, - octanol/water partition coefficients, and alkaline hydrolysis rate constants will be used in the development of a chemical sensor using fiber optic spectroscopy. These three parameters will effect the limit of detection for each compound by limiting the concentration in the detector. The parameters were estimated by linear free energy relationships and quantitative structure activity relationships using experimental data for compounds of similar chemical structure. The results of this thesis showed that the hydrophobic medium represented by 1-octanol did concentrate the OP pesticides but did not significantly concentrate CWA, CWA simulants, or CWA hydrolysis products. Correlations were evaluated for six classes of organophosphorus compounds. The limitation of this approach to predicting physicochemical parameters is not in the molecular descriptors used in the regression equations but in the availability of existing experimental data.

  11. Single crystal chemical vapor deposit diamond detector for energetic plasma measurement in space

    NASA Astrophysics Data System (ADS)

    Ogasawara, K.; Broiles, T. W.; Coulter, K. E.; Dayeh, M. A.; Desai, M. I.; Livi, S. A.; McComas, D. J.; Walther, B. C.

    2015-03-01

    This study reports the performance of single crystal chemical vapor deposit diamond detectors for measuring space plasma and energetic particles: ~7 keV energy resolution for protons with a 14 keV threshold level, and good response linearity for ions and electrons as expected from Monte-Carlo calculations of primary particle energy loss. We investigated that these diamond detectors are able to operate at high temperature (> 70 ° C) and have fast response times (< 1 ns rise time). While silicon detectors have proven capability over this energy range for space plasma measurements, diamond detectors offer a faster response, higher temperature operation, greater radiation tolerance, and immunity to light.

  12. Paint for detection of radiological or chemical agents

    DOEpatents

    Farmer, Joseph C.; Brunk, James L.; Day, Sumner Daniel

    2010-08-24

    A paint that warns of radiological or chemical substances comprising a paint operatively connected to the surface, an indicator material carried by the paint that provides an indication of the radiological or chemical substances, and a thermo-activation material carried by the paint. In one embodiment, a method of warning of radiological or chemical substances comprising the steps of painting a surface with an indicator material, and monitoring the surface for indications of the radiological or chemical substances. In another embodiment, a paint is operatively connected to a vehicle and an indicator material is carried by the paint that provides an indication of the radiological or chemical substances.

  13. Applicability of federal and state hazardous waste regulatory programs to waste chemical weapons and chemical warfare agents.

    SciTech Connect

    Haffenden, R.; Kimmell, T.

    2002-02-20

    This report reviews federal and state hazardous waste regulatory programs that govern the management of chemical weapons or chemical warfare agents. It addresses state programs in the eight states with chemical weapon storage facilities managed by the U.S. Army: Alabama, Arkansas, Colorado, Indiana, Kentucky, Maryland, Oregon, and Utah. It also includes discussions on 32 additional states or jurisdictions with known or suspected chemical weapons or chemical warfare agent presence (e.g., disposal sites containing chemical agent identification sets): Alaska, Arizona, California, Florida, Georgia, Hawaii, Idaho, Illinois, Iowa, Kansas, Louisiana, Massachusetts, Michigan, Mississippi, Missouri, Nebraska, Nevada, New Jersey, New Mexico, New York, North Carolina, Ohio, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, the U.S. Virgin Islands, Virginia, Washington, Washington, D.C., and Wyoming. Resource Conservation and Recovery Act (RCRA) hazardous waste programs are reviewed to determine whether chemical weapons or chemical warfare agents are listed hazardous wastes or otherwise defined or identified as hazardous wastes. Because the U.S. Environmental Protection Agency (EPA) military munitions rule specifically addresses the management of chemical munitions, this report also indicates whether a state has adopted the rule and whether the resulting state regulations have been authorized by EPA. Many states have adopted parts or all of the EPA munitions rule but have not yet received authorization from EPA to implement the rule. In these cases, the states may enforce the adopted munitions rule provisions under state law, but these provisions are not federally enforceable.

  14. Origins of behavioral teratology and distinctions between research on pharmaceutical agents and environmental/industrial chemicals

    SciTech Connect

    Nelson, B.K. )

    1990-07-01

    Most behavioral teratology studies have focused on pharmaceutical agents. Investigations of developmental toxicity are lacking for the majority of the nearly 100,000 industrial chemicals currently in use. Only some three dozen chemicals have been examined for behavioral/neurochemical deviations in offspring following maternal exposures. Examination of industrial agents for developmental toxicity, therefore, remains a major public health need. Most developmental research addresses the effects of pharmaceutical agents, but these studies frequently do not address environmental/industrial concerns due to fundamental differences in experimental methodology. The route, duration, and timing of exposure, usefulness of fostering of offspring, and potential concomitant exposure of both parents are all variables which should be treated differently in research on industrial chemicals as opposed to pharmaceutical agents. After briefly tracking the history of behavioral teratology, the present paper discusses differences in application of behavioral teratological principles to industrial versus pharmaceutical agents, and points to the largely untested number of industrial chemicals needing investigation. 57 references.

  15. Hand-held analyser based on microchip electrophoresis with contactless conductivity detection for measurement of chemical warfare agent degradation products

    NASA Astrophysics Data System (ADS)

    Duran, Karolina-Petkovic; Zhu, Yonggang; Chen, Chuanpin; Swallow, Anthony; Stewart, Robert; Hoobin, Pam; Leech, Patrick; Ovenden, Simon

    2008-12-01

    This paper reports on the development of a hand-held device for on-site detection of organophosphonate nerve agent degradation products. This field-deployable analyzer relies on efficient microchip electrophoresis separation of alkyl methylphosphonic acids and their sensitive contactless conductivity detection. Miniaturized, low-powered design is coupled with promising analytical performance for separating the breakdown products of chemical warfare agents such as Soman, Sarin and VX . The detector has a detection limit of about 10 μg/mL and has a good linear response in the range 10-300 μg/mL concentration range. Applicability to environmental samples is demonstrated .The new hand-held analyzer offers great promise for converting conventional ion chromatography or capillary electrophoresis sophisticated systems into a portable forensic laboratory for faster, simpler and more reliable on-site screening.

  16. Stand-off spectroscopy for the detection of chemical warfare agents

    NASA Astrophysics Data System (ADS)

    Clewes, Rhea J.; Howle, Chris R.; Stothard, David J. M.; Dunn, Malcolm H.; Robertson, Gordon; Miller, William; Malcolm, Graeme; Maker, Gareth; Cox, Rick; Williams, Brad; Russell, Matt

    2012-10-01

    The most desirable configuration for detection of toxic chemicals utilises the maximum distance between detector and hazard. This approach minimises the contamination of equipment or personnel. Where the target chemical is an involatile liquid, indirect detection of the liquid contamination is made difficult by inherently low vapour pressure. In this instance, direct detection of the chemical hazard is the best approach. Recent technology developments have allowed spectroscopic systems to provide multiple options for the stand-off detection of involatile chemical warfare agents (CWAs). Two different stand-off spectroscopic systems, based upon IR absorption and Raman spectroscopic techniques are described here. The Negative Contrast Imager (NCI) is based upon an optical parametric oscillator (OPO) source comprising a Q-switched intracavity MgO:PPLN crystal. This crystal has a fanned grating design and wavelength tuning is achieved by translating the PPLN crystal within the 1064 nm pump beam. This approach enables the production of shortwave and midwave IR radiation (1.5 - 1.8 μm and 2.6 - 3.8 μm, respectively), which is scanned across the scene of interest. Target materials that have an absorption feature commensurate with the wavelength of incoming radiation reduce the intensity of returned signal, resulting in dark pixels in the acquired image. This method enables location and classification of the target material. Stand-off Raman spectroscopy allows target chemicals to be identified at range through comparison of the acquired signature relative to a spectral database. In this work, we used a Raman system based upon a 1047 nm Nd:YLF laser source and a proprietary InGaAsP camera system. Utilisation of a longer excitation wavelength than most conventional stand-off detection systems (e.g. 532 or 785 nm) enables reduction of fluorescence from both the surface and the deposited chemicals, thereby revealing the Raman spectrum. NCI and Raman spectroscopy are able to

  17. Chemical approaches for detection and destruction of nerve agents.

    PubMed

    Ajami, Dariush; Rebek, Julius

    2013-06-28

    Since the introduction of organophosphorus (OP) compounds as nerve agents and pesticides, methods of dealing with their toxicity to humans have been intensely researched. There are studies on sensing, pretreatments, prophylactics, antidotes and therapies. There is some overlap in all of these endeavors because they have to deal with the reactivity of the phosphorus atom in various contexts. The contexts range from large spaces, the thinly spread vapors in the air, to very small spaces in the active sites of enzymes - acetylcholinesterase (AChE) or butyrylcholinesterase (BuChE) - that have reacted with the OP agent. PMID:23604461

  18. Response of Rabbiteye Blueberries to Chemical Thinning Agents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The thinning potential of various chemicals sprayed on 'Tifblue' rabbiteye blueberry was examined under field conditions for two years. Chemicals used were 7-benzylamino purine (BA), gibberellic acid (GA3), 2- naphaleneacetic acid (NAA), and 1-naphthyl N-methylcarbamate (carbaryl). BA at 75 mg/L and...

  19. Decontamination of chemical agents from drinking water infrastructure: a literature review and summary.

    PubMed

    Szabo, Jeff; Minamyer, Scott

    2014-11-01

    This report summarizes the current state of knowledge on the persistence of chemical contamination on drinking water infrastructure (such as pipes) along with information on decontamination should persistence occur. Decontamination options for drinking water infrastructure have been explored for some chemical contaminants, but important data gaps remain. In general, data on chemical persistence on drinking water infrastructure is available for inorganics such as arsenic and mercury, as well as select organics such as petroleum products, pesticides and rodenticides. Data specific to chemical warfare agents and pharmaceuticals was not found and data on toxins is scant. Future research suggestions focus on expanding the available chemical persistence data to other common drinking water infrastructure materials. Decontaminating agents that successfully removed persistent contamination from one infrastructure material should be used in further studies. Methods for sampling or extracting chemical agents from water infrastructure surfaces are needed. PMID:24565672

  20. Used tire recycling to produce granulates: evaluation of occupational exposure to chemical agents.

    PubMed

    Savary, Barbara; Vincent, Raymond

    2011-10-01

    Exposure was assessed in four facilities where used tires are turned into rubber granulates. Particulate exposure levels were measured using filter samples and gravimetric analysis. In parallel, volatile organic compounds (VOCs) screening was carried out using samples taken on activated carbon supports, followed by an analysis using a gas chromatograph coupled to a spectrometric detector. The exposure level medians are between 0.58 and 3.95 mg m(-3). Clogging of the textile fiber separation systems can lead to worker exposure; in this case, the measured concentrations can reach 41 mg m(-3). However, in contrast to the data in the literature, VOC levels >1 p.p.m. were not detected. The particulate mixtures deposited on the installation surfaces are complex; some of the chemical agents are toxic to humans. The results of this study indicate significant exposure to complex mixtures of rubber dust. Optimizing exhaust ventilation systems inside the shredders, with a cyclone for example, is essential for reducing the exposure of workers in this rapidly developing sector. PMID:21828352

  1. A convenient first aid kit for chemical and biological agents and for radiation exposure.

    PubMed

    Vijayaraghavan, R; Bhaskar, A S B; Gautam, Anshoo; Gopalan, N; Singh, A K; Singh, Beer; Flora, S J S

    2012-05-01

    The chemical and biological warfare agents are extremely toxic in nature. They act rapidly even in very small quantities and death may occur in minutes. Hence, physical and medical protection must be provided immediately to save life or avoid serious injury. A first aid kit has thus been developed for providing immediate relief from chemical and biological warfare agents (FAKCBW) with the objective of easy detection, personal decontamination, antidote for chemical warfare agents (like nerve agents, sulphur mustard, phosgene, cyanide, radiation exposure and bacterial agents), along with basic medication aid for pain, fever and inflammation. The kit box also includes a user friendly handbook with a simple standard operating procedure. In addition, the kit is rugged to withstand normal jerks, vibration and is water-proof. PMID:23029921

  2. Applications of Mass Spectrometry in Investigations of Alleged Use of Chemical Warfare Agents

    NASA Astrophysics Data System (ADS)

    Read, Robert W.

    Chemical warfare agents were used extensively throughout the twentieth century. Many such uses are well documented; however some allegations of use of chemical warfare agents were not easily confirmed. During the early 1980s interest developed into investigation of alleged use by analytical techniques, particularly mass spectrometry. Since that time, many combined chromatographic - mass spectrometric methods have been developed, both for application to the analysis of environmental and biomedical samples and for investigation of physiological interactions of chemical warfare agents. Examples are given of some of the investigations in which the author has been involved, including those into Yellow Rain and uses of chemical warfare agents in Iraq and Iran. These examples illustrate the use of combined chromatographic-mass spectrometric methods and emphasise the importance of controls in analytical investigations.

  3. Measuring indigenous photosynthetic organisms to detect chemical warefare agents in water

    DOEpatents

    Greenbaum, Elias; Sanders, Charlene A.

    2005-11-15

    A method of testing water to detect the presence of a chemical or biological warfare agent is disclosed. The method is carried out by establishing control data by providing control water containing indigenous organisms but substantially free of a chemical and a biological warfare agent. Then measuring photosynthetic activity of the control water with a fluorometer to obtain control data to compare with test data to detect the presence of the chemical or agent. The test data is gathered by providing test water comprising the same indigenous organisms as contained in the control water. Further, the test water is suspected of containing the chemical or agent to be tested for. Photosynthetic activity is also measured by fluorescence induction in the test water using a fluorometer.

  4. Microwave detection of chemical agents: a review. Special publication, January 1982-July 1984

    SciTech Connect

    Christensen, S.D.

    1986-06-01

    This report represents an overview of microwave-detection techniques and an analysis of their possible application to chemical agent point and remote sensing. Microwave rotational spectroscopy and millimeter-wavelength radar are also discussed.

  5. Chemical resistance of optical plastics and resin for level detectors

    NASA Astrophysics Data System (ADS)

    Omegna, Cicero L.; Fontes Garcia, Jonas; Ramos-Gonzáles, Roddy E.; Barbosa, Luiz C.

    2015-09-01

    A test method was developed to find the ideal optical material that supports the chemical reaction of some fuels. Optical plastics and resin were submerged for long periods of time in reservoirs of ethanol, gasoline, Diesel and biodiesel. The dimensional change and weight change of the submerged samples was measured. A special resin successfully supported the chemical attack of fuels. Samples of acrylic polymer and polycarbonate were used as type of optical plastic.

  6. Plasma mass spectrometry as a detector for chemical speciation studies.

    PubMed

    Tomlinson, M J; Lin, L; Caruso, J A

    1995-03-01

    Inductively coupled plasma mass spectrometry (ICP-MS), when coupled with the unique separating power of various chromatographic techniques, allows the detection of various elements at ultra-trace levels. The investigation of various toxic elements of environmental concern coupling relatively recent techniques, such as supercritical fluid chromatography (SFC) and capillary zone electrophoresis (CZE), to ICP-MS, is discussed. Comparisons have been made with detection limits obtained by using the flame ionization detector. The conventional technique of liquid chromatography for the speciation of vanadium, chromium and nickel is also discussed. PMID:7741220

  7. Long-term health effects of exposure to sarin and other anticholinesterase chemical warfare agents.

    PubMed

    Page, William F

    2003-03-01

    In a telephone survey of 4,022 military volunteers for a 1955-1975 program of experimental exposures to chemical agents at Edgewood, Maryland, the current health of those exposed to anticholinesterase agents was compared with that of men exposed to no active chemicals (no chemical test) and to two or more other types of chemical agents (other chemical tests). The survey posed questions about general health and about neurological and psychological deficits. There were only two statistically significant differences: volunteers in anticholinesterase agent tests reported fewer attention problems than those in other chemical tests and greater sleep disturbance than those in no chemical tests. In contrast, volunteers who reported exposure to civilian or military chemical agents outside of their participation in the Edgewood program reported many statistically significant adverse neurological and psychological effects, regardless of their experimental exposure. In this study, the health effects of self-reported, nonexperimental exposure, which are subject to recall bias, were greater than the health effects of experimental exposure. PMID:12685692

  8. Fluorescent discrimination between traces of chemical warfare agents and their mimics.

    PubMed

    Díaz de Greñu, Borja; Moreno, Daniel; Torroba, Tomás; Berg, Alexander; Gunnars, Johan; Nilsson, Tobias; Nyman, Rasmus; Persson, Milton; Pettersson, Johannes; Eklind, Ida; Wästerby, Pär

    2014-03-19

    An array of fluorogenic probes is able to discriminate between nerve agents, sarin, soman, tabun, VX and their mimics, in water or organic solvent, by qualitative fluorescence patterns and quantitative multivariate analysis, thus making the system suitable for the in-the-field detection of traces of chemical warfare agents as well as to differentiate between the real nerve agents and other related compounds. PMID:24597942

  9. Multidimensional conducting polymer nanotubes for ultrasensitive chemical nerve agent sensing.

    PubMed

    Kwon, Oh Seok; Park, Seon Joo; Lee, Jun Seop; Park, Eunyu; Kim, Taejoon; Park, Hyun-Woo; You, Sun Ah; Yoon, Hyeonseok; Jang, Jyongsik

    2012-06-13

    Tailoring the morphology of materials in the nanometer regime is vital to realizing enhanced device performance. Here, we demonstrate flexible nerve agent sensors, based on hydroxylated poly(3,4-ethylenedioxythiophene) (PEDOT) nanotubes (HPNTs) with surface substructures such as nanonodules (NNs) and nanorods (NRs). The surface substructures can be grown on a nanofiber surface by controlling critical synthetic conditions during vapor deposition polymerization (VDP) on the polymer nanotemplate, leading to the formation of multidimensional conducting polymer nanostructures. Hydroxyl groups are found to interact with the nerve agents. Representatively, the sensing response of dimethyl methylphosphonate (DMMP) as a simulant for sarin is highly sensitive and reversible from the aligned nanotubes. The minimum detection limit is as low as 10 ppt. Additionally, the sensor had excellent mechanical bendability and durability. PMID:22545863

  10. Modeling Dispersion of Chemical-Biological Agents in Three Dimensional Living Space

    SciTech Connect

    William S. Winters

    2002-02-01

    This report documents a series of calculations designed to demonstrate Sandia's capability in modeling the dispersal of chemical and biological agents in complex three-dimensional spaces. The transport of particles representing biological agents is modeled in a single room and in several connected rooms. The influence of particle size, particle weight and injection method are studied.

  11. EVALUATION OF LABORATORY TESTS TO DETERMINE THE EFFECTIVENESS OF CHEMICAL SURFACE WASHING AGENTS

    EPA Science Inventory

    When spilled oil reaches a shoreline, it coats a myriad of surfaces. n many cases, chemical agents are used to clean the shoreline substrates, with varying degrees of effectiveness. oth dispersants and surface washing agents have been used. n this study, the Environmental Protect...

  12. CHEMICAL SHORELINE CLEANING AGENTS - EVALUATION OF TWO LABORATORY PROCEDURES FOR ESTIMATING PERFORMANCE

    EPA Science Inventory

    This report presents data from studies designed to evaluate characteristics of selected bench-scale test methods for estimating cleaning performance of chemical agents for removal of oil from substrate surfaces. uch agents have the potential to be used to remove oil that might st...

  13. Sensitivity of human dental pulp cells to eighteen chemical agents used for endodontic treatments in dentistry.

    PubMed

    Kobayashi, Morio; Tsutsui, Takeo W; Kobayashi, Tomoko; Ohno, Maki; Higo, Yukari; Inaba, Tomohiro; Tsutsui, Takeki

    2013-01-01

    To determine the adverse effects against human dental pulp tissue, the sensitivity of human dental pulp cells (D824 cells) to 18 chemical agents used for endodontic treatments in dentistry was examined. The cytotoxicity, as determined by a decrease in colony-forming ability of cells treated with the chemical agents, increased as the concentration increased. As a quantitative measure of the cytotoxic effect, LC(50), the concentration which induces a 50% lethality, was extrapolated from the concentration-response curves. The rank of the chemical agents according to their cytotoxic effect (LC(50)) was sodium arsenite > formaldehyde > hydrogen peroxide > zinc oxide > thymol ≈ iodoform ≈ eugenol > guaiacol > ethylenediaminetetraacetic acid ≈ iodine > procaine > lidocaine ≈ chloramphenicol ≈ m-cresol > calcium hydroxide ≈ sodium hypochlorite ≈ phenol ≈ p-phenolsulfonic acid. To compare the cytotoxicity and the levels of apoptosis and mRNA expression of five genes related to the function of dental pulp tissue, D824 cells treated with the LC(50) concentrations of chemical agents were assayed by the TUNEL method and quantitative reverse transcription polymerase chain reaction analysis, respectively. The inducibility of apoptotic cells and the level of mRNA expression of the genes varied with the chemical agents, indicating that both effects occurred independent of the rank of cytotoxic effect of the chemical agents. The results not only provide information concerning cytotoxicity of various chemical agents to human dental pulp cells, but also show an insight into the diversity of the pharmacodynamic action of the chemical agents. PMID:22083529

  14. Modeling the transport of chemical warfare agents and simulants in polymeric substrates for reactive decontamination

    NASA Astrophysics Data System (ADS)

    Pearl, Thomas; Mantooth, Brent; Varady, Mark; Willis, Matthew

    2014-03-01

    Chemical warfare agent simulants are often used for environmental testing in place of highly toxic agents. This work sets the foundation for modeling decontamination of absorbing polymeric materials with the focus on determining relationships between agents and simulants. The correlations of agents to simulants must consider the three way interactions in the chemical-material-decontaminant system where transport and reaction occur in polymer materials. To this end, diffusion modeling of the subsurface transport of simulants and live chemical warfare agents was conducted for various polymer systems (e.g., paint coatings) with and without reaction pathways with applied decontamination. The models utilized 1D and 2D finite difference diffusion and reaction models to simulate absorption and reaction in the polymers, and subsequent flux of the chemicals out of the polymers. Experimental data including vapor flux measurements and dynamic contact angle measurements were used to determine model input parameters. Through modeling, an understanding of the relationship of simulant to live chemical warfare agent was established, focusing on vapor emission of agents and simulants from materials.

  15. Decontamination of chemical warfare agents. Final report, June 1991-August 1992

    SciTech Connect

    Yang, Y.C.; Baker, J.A.; Ward, J.R.

    1992-12-01

    Reviews of the development of systems to decontaminate chemical warfare agents and of the chemical reactions involved in decontamination are presented in this report. Decontamination is defined as the rapid removal of agents from contaminated surfaces. Simple physical methods, such as evaporation, washing, and scrubbing, fall under this broad definition; however, most of the decontaminants contain reactive components to detoxify as well as remove the agents. In nonaqueous media, a strong base reacts rapidly with the four major chemical agents; mustard, VX, GB, and GD. In aqueous mixtures, H and VX are detoxified with an oxidant; whereas, the G agents are hydrolyzed with an excess of hydroxide ion. Current research efforts are aimed at developing effective decontaminants that are noncorrosive, nontoxic, and environmentally safe. Both catalytic and enzymatic approaches using solid or heterogeneous liquid media are being pursued. A fundamental understanding of the chemical nature of the agents is essential in the success of these approaches.... Decontamination, Sarin, VX, Chemical agents, Soman, Hydrolysis, Review, Mustard gas.

  16. Protocol for determination of chemical warfare agent simulant movement through porous media

    SciTech Connect

    Jenkins, R.A.; Buchanan, M.V.; Merriweather, R.; Ilgner, R.H.; Gayle, T.M.; Moneyhun, J.H.; Watson, A.P.

    1992-07-01

    In the event of an unplanned release of chemical warfare agent during any phase of the Chemical Stockpile Disposal Program (CSDP), a (small) potential exists for contamination of buildings and materials used in their construction. Guidelines for unrestricted access to potentially agent-contaminated private and public property are presently undefined due to uncertainties regarding the adequacy of decontaminating porous surfaces such as wood, masonry and gypsum wall board. Persistent agents such as VX or mustard are particularly problematic. The report which follows documents a measurement protocol developed in a scoping investigation characterizing the permeation of chemical warfare agent simulants (diisopropylmethyl phosphonate (DIMP) for warfare agent GB, dimethylmethyl phosphonate (DMMP) for warfare agent VX and chlorethylethyl sulfide (CEES) for warfare agent sulfur mustard) through several, common porous, construction materials. The porous media'' selected for examination were wood, brick, cinder block, and gypsum wall board. Simulants were tested rather than actual warfare agents because of their low toxicity, commercial availability, and the lack of surety capability at Oak Ridge National Laboratory (ORNL). The present work is considered a protocol for confirmation testing with live'' agents.

  17. Protocol for determination of chemical warfare agent simulant movement through porous media

    SciTech Connect

    Jenkins, R.A.; Buchanan, M.V.; Merriweather, R.; Ilgner, R.H.; Gayle, T.M.; Moneyhun, J.H.; Watson, A.P.

    1992-07-01

    In the event of an unplanned release of chemical warfare agent during any phase of the Chemical Stockpile Disposal Program (CSDP), a (small) potential exists for contamination of buildings and materials used in their construction. Guidelines for unrestricted access to potentially agent-contaminated private and public property are presently undefined due to uncertainties regarding the adequacy of decontaminating porous surfaces such as wood, masonry and gypsum wall board. Persistent agents such as VX or mustard are particularly problematic. The report which follows documents a measurement protocol developed in a scoping investigation characterizing the permeation of chemical warfare agent simulants [diisopropylmethyl phosphonate (DIMP) for warfare agent GB, dimethylmethyl phosphonate (DMMP) for warfare agent VX and chlorethylethyl sulfide (CEES) for warfare agent sulfur mustard] through several, common porous, construction materials. The ``porous media`` selected for examination were wood, brick, cinder block, and gypsum wall board. Simulants were tested rather than actual warfare agents because of their low toxicity, commercial availability, and the lack of surety capability at Oak Ridge National Laboratory (ORNL). The present work is considered a protocol for confirmation testing with ``live`` agents.

  18. Novel fluorescence-based integrated sensor for chemical and biological agent detection

    NASA Astrophysics Data System (ADS)

    Frye-Mason, Greg; Leuschen, Martin; Wald, Lara; Paul, Kateri; Hancock, Lawrence F.; Fagan, Steve; Krouse, Justin; Hutchinson, Kira D.

    2004-12-01

    There is a renewed interest in the development of chemical and biological agent sensors due to the increased threat of weapons deployment by terrorist organizations and rogue states. Optically based sensors address the needs of military and homeland security forces in that they are reliable, rapidly deployed, and can provide continuous monitoring with little to no operator involvement. Nomadics has developed optically based chemical weapons sensors that utilize reactive fluorescent chromophores initially developed by Professor Tim Swager at MIT. The chromophores provide unprecedented sensitivity and selectivity toward toxic industrial chemicals and certain chemical weapon agents. The selectivity is based upon the reactivity of the G-class nerve agents (phosphorylation of acetylcholinesterase enzyme) that makes them toxic. Because the sensor recognizes the reactivity of strong electrophiles and not molecular weight, chemical affinity or ionizability, our system detects a specific class of reactive agents and will be able to detect newly developed or modified agents that are not currently known. We have recently extended this work to pursue a combined chemical/biological agent sensor system incorporating technologies based upon novel deep ultraviolet (UV) light emitting diodes (LEDs) developed out of the DARPA Semiconductor UV Optical Sources (SUVOS) program.

  19. Reactive skin decontamination lotion (RSDL) for the decontamination of chemical warfare agent (CWA) dermal exposure.

    PubMed

    Schwartz, M D; Hurst, C G; Kirk, M A; Reedy, S J D; Braue, E H

    2012-08-01

    Rapid decontamination of the skin is the single most important action to prevent dermal absorption of chemical contaminants in persons exposed to chemical warfare agents (CWA) and toxic industrial chemicals (TICs) as a result of accidental or intentional release. Chemicals on the skin may be removed by mechanical means through the use of dry sorbents or water. Recent interest in decontamination systems which both partition contaminants away from the skin and actively neutralize the chemical has led to the development of several reactive decontamination solutions. This article will review the recently FDA-approved Reactive Skin Decontamination Lotion (RSDL) and will summarize the toxicity and efficacy studies conducted to date. Evidence of RSDL's superior performance against vesicant and organophosphorus chemical warfare agents compared to water, bleach, and dry sorbents, suggests that RSDL may have a role in mass human exposure chemical decontamination in both the military and civilian arenas. PMID:22352732

  20. Quantitative Infrared Spectra of Vapor Phase Chemical Agents

    SciTech Connect

    Sharpe, Steven W.; Johnson, Timothy J.; Chu, P M.; Kleimeyer, J; Rowland, Brad; Gardner, Patrick J.

    2003-04-21

    Quantitative high resolution (0.1 cm -1) infrared spectra have been acquired for a number of pressure broadened (101.3 KPa N2), vapor phase chemicals including: Sarin (GB), Soman (GD), Tabun (GA), Cyclosarin (GF), VX, nitrogen mustard (HN3), sulfur mustard (HD) and Lewisite (L).

  1. CMOS buried multi-junction (BMJ) detector for bio-chemical analysis

    NASA Astrophysics Data System (ADS)

    Lu, Guo-Neng; Courcier, Thierry; Mamdy, Bastien; Feruglio, Sylvain; Charette, Paul G.; Aimez, Vincent; Romain, Olivier; Pittet, Patrick

    2015-10-01

    The CMOS buried multi-junction (BMJ) detector with multiple outputs has distinct spectral responses that may be exploited for applications such as bio-chemical analysis. We tackle here dark current issue by identifying different components inside the detector structure. The identification methods are based on the observation of bias and temperature dependence, as well as measurements of test detector chip integrating different design variations. Surface thermal generation may become predominant when the detector size shrinks, thus causing dark current degradation. To prevent this effect, we propose a low-sized detector structure with passivation of all its surrounding Si/SiO2 interface areas. Also for the detector readout, we present a multi-channel charge-amplifier architecture with noise analysis. Effects of noise coming from amplifiers and related to the coupled detector's dynamic conductances are illuminated. To pick up weak signals, synchronous detection can be implemented. A BDJ (Buried Double Junction) detector chip designed with a switched-phase architectural approach gives a minimum detectable signal of 15μlx@555nm or 1μlx@555nm at 27°C or - 10°C, for an integration time of 3s or 45s respectively.

  2. Evaluation of Chemical Warfare Agent Percutaneous Vapor Toxicity: Derivation of Toxicity Guidelines for Assessing Chemical Protective Ensembles.

    SciTech Connect

    Watson, A.P.

    2003-07-24

    Percutaneous vapor toxicity guidelines are provided for assessment and selection of chemical protective ensembles (CPEs) to be used by civilian and military first responders operating in a chemical warfare agent vapor environment. The agents evaluated include the G-series and VX nerve agents, the vesicant sulfur mustard (agent HD) and, to a lesser extent, the vesicant Lewisite (agent L). The focus of this evaluation is percutaneous vapor permeation of CPEs and the resulting skin absorption, as inhalation and ocular exposures are assumed to be largely eliminated through use of SCBA and full-face protective masks. Selection of appropriately protective CPE designs and materials incorporates a variety of test parameters to ensure operability, practicality, and adequacy. One aspect of adequacy assessment should be based on systems tests, which focus on effective protection of the most vulnerable body regions (e.g., the groin area), as identified in this analysis. The toxicity range of agent-specific cumulative exposures (Cts) derived in this analysis can be used as decision guidelines for CPE acceptance, in conjunction with weighting consideration towards more susceptible body regions. This toxicity range is bounded by the percutaneous vapor estimated minimal effect (EME{sub pv}) Ct (as the lower end) and the 1% population threshold effect (ECt{sub 01}) estimate. Assumptions of exposure duration used in CPE certification should consider that each agent-specific percutaneous vapor cumulative exposure Ct for a given endpoint is a constant for exposure durations between 30 min and 2 hours.

  3. Chemical structure and pharmacokinetics of novel quinolone agents represented by avarofloxacin, delafloxacin, finafloxacin, zabofloxacin and nemonoxacin.

    PubMed

    Kocsis, Bela; Domokos, J; Szabo, D

    2016-01-01

    Quinolones are potent antimicrobial agents with a basic chemical structure of bicyclic ring. Fluorine atom at position C-6 and various substitutions on the basic quinolone structure yielded fluoroquinolones, namely norfloxacin, ciprofloxacin, levofloxacin, moxifloxacin and numerous other agents. The target molecules of quinolones and fluoroquinolones are bacterial gyrase and topoisomerase IV enzymes. Broad-spectrum and excellent tissue penetration make fluoroquinolones potent agents but their toxic side effects and increasing number of resistant pathogens set limits on their use. This review focuses on recent advances concerning quinolones and fluoroquinolones, we will be summarising chemical structure, mode of action, pharmacokinetic properties and toxicity. We will be describing fluoroquinolones introduced in clinical trials, namely avarofloxacin, delafloxacin, finafloxacin, zabofloxacin and non-fluorinated nemonoxacin. These agents have been proved to have enhanced antibacterial effect even against ciprofloxacin resistant pathogens, and found to be well tolerated in both oral and parenteral administrations. These features are going to make them potential antimicrobial agents in the future. PMID:27215369

  4. 32 CFR 174.16 - Real property containing explosive or chemical agent hazards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 1 2010-07-01 2010-07-01 false Real property containing explosive or chemical... REALIGNMENT Environmental Matters § 174.16 Real property containing explosive or chemical agent hazards. The DoD Component controlling real property known to contain or suspected of containing explosive...

  5. 32 CFR 174.16 - Real property containing explosive or chemical agent hazards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 1 2011-07-01 2011-07-01 false Real property containing explosive or chemical... REALIGNMENT Environmental Matters § 174.16 Real property containing explosive or chemical agent hazards. The DoD Component controlling real property known to contain or suspected of containing explosive...

  6. 32 CFR 174.16 - Real property containing explosive or chemical agent hazards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 1 2012-07-01 2012-07-01 false Real property containing explosive or chemical... REALIGNMENT Environmental Matters § 174.16 Real property containing explosive or chemical agent hazards. The DoD Component controlling real property known to contain or suspected of containing explosive...

  7. 32 CFR 174.16 - Real property containing explosive or chemical agent hazards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 1 2013-07-01 2013-07-01 false Real property containing explosive or chemical... REALIGNMENT Environmental Matters § 174.16 Real property containing explosive or chemical agent hazards. The DoD Component controlling real property known to contain or suspected of containing explosive...

  8. PERMANENCE OF BIOLOGICAL AND CHEMICAL WARFARE AGENTS IN MUNICIPAL SOLID WASTE LANDFILL LEACHATES

    EPA Science Inventory

    The objective of this work is to permit EPA/ORD's National Homeland Security Research Center (NHSRC) and Edgewood Chemical Biological Center to collaborate together to test the permanence of biological and chemical warfare agents in municipal solid waste landfills. Research into ...

  9. Analytical methods for environmental sampling of chemical warfare agents and their degradation products

    SciTech Connect

    Watson, A.P.; Kistner, S.

    1995-06-01

    This first technical conference promoted the standardization of analytical procotols to reliably detect chemical warfare agents and their degradation products in soil, water, and other complex environmental media. This supports the various chemical weapons disposal and emergency preparedness programs, Chemical Weapons Convention treaty compliance, installation restoration and base closure decisions. Five major topics were addressed: Implementation for treaty compliance, installation, restoration and stockpile disposal decisions, existing analytical methods, practical applications of existing analytical techniques, immunoassay technologies, environmental and biological fate of agents and their degradation products. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  10. Use of hyperspectral remote sensing for detection and monitoring of chemical and biological agents: a survey

    NASA Astrophysics Data System (ADS)

    Gomez, Richard B.; Dasgupta, Swarvanu

    2004-12-01

    This paper surveys the potential use of hyperspectral imaging technology for standoff detection of chemical and biological agents in terrorism defense applications. In particular it focuses on the uses of hyperspectral imaging technology to detect and monitor chemical and biological attacks. In so doing it examines current technologies, their advantages and disadvantages, and investigates the possible role of hyperspectral imaging for homeland security applications. The study also addresses and provides applicable solutions for several of the potential challenges that currently create barriers to the full use of hyperspectral technology in the standoff detection of likely available chemical and biological agents.

  11. Evaluation of different small bowel contrast agents by multi - detector row CT

    PubMed Central

    Wang, Yong-Ren; Yu, Xiao-Li; Peng, Zhi-Yi

    2015-01-01

    Objective: This study aims to evaluate the effects of different oral small bowel contrast agents towards the intestinal dilatation and intestinal wall structure exhibition by the abdominal multi - detector row CT (MDCT) examination. Methods: 80 patients were performed the whole abdominal CT examination, then randomly divided into four groups, with 20 patients in each group. 45 minutes before the CT examination, the patients were served with a total of 1800 ml pure water, pure milk, dilute lactulose solution and isotonic mannitol solution, respectively. Results: The images were blinded read by two experienced abdominal radiologists in the workstation, the cross-sectional diameters of duodenum, jejunum, proximal and terminal ends of ileum of each patient were measured, then the analysis of variance was performed to analyze the differences in the intestinal dilatation among the experimental groups. The scoring method was used to score the intestinal dilatation and intestinal structure exhibition. The diluted lactulose solution and 2.5% mannitol exhibited the best intestinal dilation degrees. Similarly, the diluted lactulose solution and 2.5% mannitol exhibited the highest scores in the entire small bowel dilatation degree and intestinal structure exhibition. Conclusions: 2.5% osmotic mannitol and the diluted lactulose solution enabled the full dilatation of small bowel, and could clearly exhibit the wall structure. PMID:26629131

  12. Can Chemical Mouthwash Agents Achieve Plaque/Gingivitis Control?

    PubMed

    Van der Weijden, Fridus A; Van der Sluijs, Eveline; Ciancio, Sebastian G; Slot, Dagmar E

    2015-10-01

    Also note that structured abstracts are not allowed per journal style: What is the effect of a mouthwash containing various active chemical ingredients on plaque control and managing gingivitis in adults based on evidence gathered from existing systematic reviews? The summarized evidence suggests that mouthwashes containing chlorhexidine(CHX) and essential oils (EO) had a large effect supported by a strong body of evidence. Also there was strong evidence for a moderate effect of cetylpyridinium chloride(CPC). Evidence suggests that a CHX mouthwash is the first choice, the most reliable alternative is EO. No difference between CHX and EO with respect to gingivitis was observed. PMID:26427569

  13. Mass spectrometry in identification of ecotoxicants including chemical and biological warfare agents.

    PubMed

    Lebedev, Albert T

    2005-09-01

    Mass spectrometry is a unique tool to detect and identify trace levels of organic and bioorganic compounds as well as microorganisms in the environment. The range of potential chemical warfare (CW) and biological warfare (BW) agents is very broad. An important advantage of mass spectrometry over other techniques involves potential for full spectrum detection of chemical and biological agents including mid-spectrum materials (i.e. bioactive peptides, toxins, etc.) for which biological approaches are inadequate. Being very fast (seconds and minutes), extremely sensitive (zeptomoles 10(-21)), and informative (detailed qualitative and quantitative composition of mixtures containing hundreds of chemicals), mass spectrometry is a principal analytical tool at the sites of destruction of CW. Due to its unique features, mass spectrometry is applied not only for the detection of CW agents, but for the analysis of products of metabolism and degradation of these agents in organisms or environment as well. The present paper deals with some examples of successful application of mass spectrometry for the analyses of ecotoxicants, chemical warfare agents, explosives, and microorganisms including biology warfare agents. PMID:16024060

  14. Mass spectrometry in identification of ecotoxicants including chemical and biological warfare agents

    SciTech Connect

    Lebedev, Albert T. . E-mail: lebedev@org.chem.msu.ru

    2005-09-01

    Mass spectrometry is a unique tool to detect and identify trace levels of organic and bioorganic compounds as well as microorganisms in the environment. The range of potential chemical warfare (CW) and biological warfare (BW) agents is very broad. An important advantage of mass spectrometry over other techniques involves potential for full spectrum detection of chemical and biological agents including mid-spectrum materials (i.e. bioactive peptides, toxins, etc.) for which biological approaches are inadequate. Being very fast (seconds and minutes), extremely sensitive (zeptomoles 10{sup -21}), and informative (detailed qualitative and quantitative composition of mixtures containing hundreds of chemicals), mass spectrometry is a principal analytical tool at the sites of destruction of CW. Due to its unique features, mass spectrometry is applied not only for the detection of CW agents, but for the analysis of products of metabolism and degradation of these agents in organisms or environment as well. The present paper deals with some examples of successful application of mass spectrometry for the analyses of ecotoxicants, chemical warfare agents, explosives, and microorganisms including biology warfare agents.

  15. Airborne exposure limits for chemical and biological warfare agents: is everything set and clear?

    PubMed

    Sabelnikov, Alex; Zhukov, Vladimir; Kempf, C Ruth

    2006-08-01

    Emergency response strategies (guidelines) for biological, chemical, nuclear, or radiological terrorist events should be based on scientifically established exposure limits for all the agents or materials involved. In the case of a radiological terrorist event, emergency response guidelines (ERG) have been worked out. In the case of a terrorist event with the use of chemical warfare (CW) agents the situation is not that clear, though the new guidelines and clean-up values are being generated based on re-evaluation of toxicological and risk data. For biological warfare (BW) agents, such guidelines do not yet exist. In this paper the current status of airborne exposure limits (AELs) for chemical and biological warfare (CBW) agents are reviewed. Particular emphasis is put on BW agents that lack such data. An efficient, temporary solution to bridge the gap in experimental infectious data and to set provisional AELs for BW agents is suggested. It is based on mathematically generated risks of infection for BW agents grouped by their alleged ID50 values in three categories: with low, intermediate and high ID50 values. PMID:16854669

  16. Development of Single Crystal Chemical Vapor Deposition Diamonds for Detector Applications

    SciTech Connect

    Harris Kagan; K.K. Gan; Richard Kass

    2009-03-31

    Diamond was studied as a possible radiation hard technology for use in future high radiation environments. With the commissioning of the LHC expected in 2009, and the LHC upgrades expected in 2013, all LHC experiments are planning for detector upgrades which require radiation hard technologies. Chemical Vapor Deposition (CVD) diamond has now been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle and CDF and is installed in all LHC experiments. As a result, this material is now being discussed as an alternative sensor material for tracking very close to the interaction region of the super-LHC where the most extreme radiation conditions will exist. Our work addressed the further development of the new material, single-crystal Chemical Vapor Deposition diamond, towards reliable industrial production of large pieces and new geometries needed for detector applications.

  17. Development of Single Crystal Chemical Vapor Deposition Diamonds for Detector Applications

    SciTech Connect

    Rainer Wallny

    2012-10-15

    Diamond was studied as a possible radiation hard technology for use in future high radiation environments. With the commissioning of the LHC expected in 2010, and the LHC upgrades expected in 2015, all LHC experiments are planning for detector upgrades which require radiation hard technologies. Chemical Vapor Deposition (CVD) diamond has now been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle and CDF and is installed and operational in all LHC experiments. As a result, this material is now being discussed as an alternative sensor material for tracking very close to the interaction region of the super-LHC where the most extreme radiation conditions will exist. Our work addressed the further development of the new material, single-crystal Chemical Vapor Deposition diamond, towards reliable industrial production of large pieces and new geometries needed for detector applications.

  18. Analysis of Surface Chemistry and Detector Performance of Chemically Process CdZnTe crystals

    SciTech Connect

    HOSSAIN, A.; Yang, G.; Sutton, J.; Zergaw, T.; Babalola, O. S.; Bolotnikov, A. E.; Camarda. ZG. S.; Gul, R.; Roy, U. N., and James, R. B.

    2015-10-05

    The goal is to produce non-conductive smooth surfaces for fabricating low-noise and high-efficiency CdZnTe devices for gamma spectroscopy. Sample preparation and results are discussed. The researachers demonstrated various bulk defects (e.g., dislocations and sub-grain boundaries) and surface defects, and examined their effects on the performance of detectors. A comparison study was made between two chemical etchants to produce non-conductive smooth surfaces. A mixture of bromine and hydrogen peroxide proved more effective than conventional bromine etchant. Both energy resolution and detection efficiency of CZT planar detectors were noticeably increased after processing the detector crystals using improved chemical etchant and processing methods.

  19. Detectors

    DOEpatents

    Orr, Christopher Henry; Luff, Craig Janson; Dockray, Thomas; Macarthur, Duncan Whittemore; Bounds, John Alan; Allander, Krag

    2002-01-01

    The apparatus and method provide techniques through which both alpha and beta emission determinations can be made simultaneously using a simple detector structure. The technique uses a beta detector covered in an electrically conducting material, the electrically conducting material discharging ions generated by alpha emissions, and as a consequence providing a measure of those alpha emissions. The technique also offers improved mountings for alpha detectors and other forms of detectors against vibration and the consequential effects vibration has on measurement accuracy.

  20. Quantitative Infrared Spectra of Vapor Phase Chemical Agents

    SciTech Connect

    Sharpe, Steven W.; Johnson, Timothy J.; Chu, P. M.; Kleimeyer, J.; Rowland, Brad

    2003-08-01

    Quantitative, moderately high resolution (0.1 cm-1) infrared spectra have been acquired for a number of nitrogen broadened (1 atm N2) vapor phase chemicals including: Sarin (GB), Soman (GD), Tabun (GA), Cyclosarin (GF), VX, Nitrogen Mustard (HN3), Sulfur Mustard (HD), and Lewisite (L). The spectra are acquired using a heated, flow-through White Cell1 of 5.6 meter optical path length. Each reported spectrum represents a statistical fit to Beer’s law, which allows for a rigorous calculation of uncertainty in the absorption coefficients. As part of an ongoing collaboration with the National Institute of Standards and Technology (NIST), cross-laboratory validation is a critical aspect of this work. In order to identify possible errors in the Dugway flow-through system, quantitative spectra of isopropyl alcohol from both NIST and Pacific Northwest National Laboratory (PNNL) are compared to similar data taken at Dugway proving Grounds (DPG).

  1. [Measurement of chemical agents in metallurgy field: electric steel plant].

    PubMed

    Cottica, D; Grignani, E; Ghitti, R; Festa, D; Apostoli, P

    2012-01-01

    The steel industry maintains its important position in the context of the Italian production involving thousands of workers. The iron and steel processes are divided into primary steel industry, production of intermediate minerals, and secondary steel, scrap from the production of semi-finished industrial and consumer sector (metal inserted into components and metal used for dissipative uses, primarily coatings) and industrial waste. The paper presents the results of environmental monitoring carried out in some electric steel plant for the measurement of airborne chemicals that characterize the occupational exposure of workers employed in particular area like electric oven, to treatment outside the furnace, continuous casting area. For the sampling of the pollutants were used both personal and in fixed positions samplers. The pollutants measured are those typical of steel processes inhalable dust, metals, respirable dust, crystalline silica, but also Polycyclic Aromatic Hydrocarbons (PAH), polychlorinated dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). PMID:23213795

  2. Mortality among chemical workers exposed to benzene and other agents

    SciTech Connect

    Decoufle, P.; Blattner, W.A.; Blair, A.

    1983-02-01

    A historical cohort mortality study was conducted of 259 male employees of a chemical plant where benzene has been used in large quantites. The study group included all persons who were employed by the Company any time between January 1, 1947 and December 31, 1960. The cohort was followed through December 31, 1977 at which time 58 known deaths were identified. The only unusual findings was four deaths from lymphoreticular cancers when 1.1 would have been expected on the basis of national mortality rates. Three of the deaths were due to leukemia and one was caused by multiple myeloma. In addition, one of the leukemia deaths had multiple myeloma listed on the death certificate. The findings are consistent with previous reports of leukemia following occupational exposure to benzene and raise the possibility that multiple myeloma could be linked to benzene, also.

  3. Detection/classification/quantification of chemical agents using an array of surface acoustic wave (SAW) devices

    NASA Astrophysics Data System (ADS)

    Milner, G. Martin

    2005-05-01

    ChemSentry is a portable system used to detect, identify, and quantify chemical warfare (CW) agents. Electro chemical (EC) cell sensor technology is used for blood agents and an array of surface acoustic wave (SAW) sensors is used for nerve and blister agents. The combination of the EC cell and the SAW array provides sufficient sensor information to detect, classify and quantify all CW agents of concern using smaller, lighter, lower cost units. Initial development of the SAW array and processing was a key challenge for ChemSentry requiring several years of fundamental testing of polymers and coating methods to finalize the sensor array design in 2001. Following the finalization of the SAW array, nearly three (3) years of intensive testing in both laboratory and field environments were required in order to gather sufficient data to fully understand the response characteristics. Virtually unbounded permutations of agent characteristics and environmental characteristics must be considered in order to operate against all agents and all environments of interest to the U.S. military and other potential users of ChemSentry. The resulting signal processing design matched to this extensive body of measured data (over 8,000 agent challenges and 10,000 hours of ambient data) is considered to be a significant advance in state-of-the-art for CW agent detection.

  4. Activation of aluminum as an effective reducing agent by pitting corrosion for wet-chemical synthesis.

    PubMed

    Li, Wei; Cochell, Thomas; Manthiram, Arumugam

    2013-01-01

    Metallic aluminum (Al) is of interest as a reducing agent because of its low standard reduction potential. However, its surface is invariably covered with a dense aluminum oxide film, which prevents its effective use as a reducing agent in wet-chemical synthesis. Pitting corrosion, known as an undesired reaction destroying Al and is enhanced by anions such as F⁻, Cl⁻, and Br⁻ in aqueous solutions, is applied here for the first time to activate Al as a reducing agent for wet-chemical synthesis of a diverse array of metals and alloys. Specifically, we demonstrate the synthesis of highly dispersed palladium nanoparticles on carbon black with stabilizers and the intermetallic Cu₂Sb/C, which are promising candidates, respectively, for fuel cell catalysts and lithium-ion battery anodes. Atomic hydrogen, an intermediate during the pitting corrosion of Al in protonic solvents (e.g., water and ethylene glycol), is validated as the actual reducing agent. PMID:23390579

  5. Activation of Aluminum as an Effective Reducing Agent by Pitting Corrosion for Wet-chemical Synthesis

    PubMed Central

    Li, Wei; Cochell, Thomas; Manthiram, Arumugam

    2013-01-01

    Metallic aluminum (Al) is of interest as a reducing agent because of its low standard reduction potential. However, its surface is invariably covered with a dense aluminum oxide film, which prevents its effective use as a reducing agent in wet-chemical synthesis. Pitting corrosion, known as an undesired reaction destroying Al and is enhanced by anions such as F−, Cl−, and Br− in aqueous solutions, is applied here for the first time to activate Al as a reducing agent for wet-chemical synthesis of a diverse array of metals and alloys. Specifically, we demonstrate the synthesis of highly dispersed palladium nanoparticles on carbon black with stabilizers and the intermetallic Cu2Sb/C, which are promising candidates, respectively, for fuel cell catalysts and lithium-ion battery anodes. Atomic hydrogen, an intermediate during the pitting corrosion of Al in protonic solvents (e.g., water and ethylene glycol), is validated as the actual reducing agent. PMID:23390579

  6. Plasma flame for mass purification of contaminated air with chemical and biological warfare agents

    SciTech Connect

    Uhm, Han S.; Shin, Dong H.; Hong, Yong C.

    2006-09-18

    An elimination of airborne simulated chemical and biological warfare agents was carried out by making use of a plasma flame made of atmospheric plasma and a fuel-burning flame, which can purify the interior air of a large volume in isolated spaces such as buildings, public transportation systems, and military vehicles. The plasma flame generator consists of a microwave plasma torch connected in series to a fuel injector and a reaction chamber. For example, a reaction chamber, with the dimensions of a 22 cm diameter and 30 cm length, purifies an airflow rate of 5000 lpm contaminated with toluene (the simulated chemical agent) and soot from a diesel engine (the simulated aerosol for biological agents). Large volumes of purification by the plasma flame will free mankind from the threat of airborne warfare agents. The plasma flame may also effectively purify air that is contaminated with volatile organic compounds, in addition to eliminating soot from diesel engines as an environmental application.

  7. Plasma flame for mass purification of contaminated air with chemical and biological warfare agents

    NASA Astrophysics Data System (ADS)

    Uhm, Han S.; Shin, Dong H.; Hong, Yong C.

    2006-09-01

    An elimination of airborne simulated chemical and biological warfare agents was carried out by making use of a plasma flame made of atmospheric plasma and a fuel-burning flame, which can purify the interior air of a large volume in isolated spaces such as buildings, public transportation systems, and military vehicles. The plasma flame generator consists of a microwave plasma torch connected in series to a fuel injector and a reaction chamber. For example, a reaction chamber, with the dimensions of a 22cm diameter and 30cm length, purifies an airflow rate of 5000lpm contaminated with toluene (the simulated chemical agent) and soot from a diesel engine (the simulated aerosol for biological agents). Large volumes of purification by the plasma flame will free mankind from the threat of airborne warfare agents. The plasma flame may also effectively purify air that is contaminated with volatile organic compounds, in addition to eliminating soot from diesel engines as an environmental application.

  8. Model of carrier dynamics in chemical vapor deposition diamond detectors

    SciTech Connect

    Borchi, Emilio; Lagomarsino, Stefano; Mersi, Stefano; Sciortino, Silvio

    2005-03-01

    We propose a quantitative model of electronic transport on the basis of a conductivity characterization of diamond-based sensors exposed to {beta} radiation. Some of the investigated samples have been irradiated with neutron up to a fluence of 2x10{sup 15}/cm{sup 2}. Radiation-induced current measurements have been performed to study the trapping and recombination of deep defect levels in the diamond band gap. We present a quantitative analysis of the passivation of deep traps and the release of carriers during thermal fading between consecutive exposures. We determine the density of trap states per unit volume and per unit energy and their capture cross sections. We also evaluate the modification of these parameters after neutron irradiation. Our analysis gives the cross sections of the traps involved in our measurements with an accuracy of 20-50%, which is far better than that attainable with thermal spectroscopy. Our results on the capture cross section of the recombination centers agree with relevant works presented in literature on natural IIa diamond. We propose that some defects are of the same nature in chemical vapor deposition diamond, but their concentration is far lower in the state-of-the-art material. We also study a modification of the trap level distribution after neutron irradiation. Finally we propose a rationale for the improvement obtained in recent years in the performances of top quality polycrystalline diamond sensors.

  9. Laser-induced chemical liquid phase deposition of copper from aqueous solutions without reducing agents

    SciTech Connect

    Kochemirovsky, V A; Tumkin, I I; Logunov, L S; Safonov, S V; Menchikov, Leonid G

    2012-08-31

    Laser-induced chemical liquid phase deposition of copper without a traditional reducing agent has been used for the first time to obtain conductive patterns on a dielectric surface having a reducing ability. It is shown that phenol-formaldehyde binder of the dielectric (glass fibre) can successfully play the role of a reducing agent in this process. The resulting copper sediments have low electrical resistance and good topology. (interaction of laser radiation with matter. laser plasmas)

  10. Surface-enhanced Raman scattering (SERS) detection for chemical and biological agents

    NASA Astrophysics Data System (ADS)

    Yan, Fei; Stokes, David L.; Wabuyele, Musundi B.; Griffin, Guy D.; Vass, Arpad A.; Vo-Dinh, Tuan

    2004-07-01

    Surface-enhanced Raman scattering (SERS) spectra of chemical agent simulants such as dimethyl methylphonate (DMMP), pinacolyl methylphosphonate (PMP), diethyl phosphoramidate (DEPA), and 2-chloroethyl ethylsulfide (CEES), and biological agent simulants such as bacillus globigii (BG), erwinia herbicola (EH), and bacillus thuringiensis (BT) were obtained from silver oxide film-deposited substrates. Thin AgO films ranging in thickness from 50 nm to 250 nm were produced by chemical bath deposition onto glass slides. Further Raman intensity enhancements were noticed in UV irradiated surfaces due to photo-induced Ag nanocluster formation, which may provide a possible route to producing highly useful plasmonic sensors for the detection of chemical and biological agents upon visible light illumination.

  11. Toxicity of the Organophosphate Chemical Warfare Agents GA, GB, and VX: Implications for Public Protection.

    PubMed Central

    Munro, N

    1994-01-01

    The nerve agents, GA, GB, and VX are organophosphorus esters that form a major portion of the total agent volume contained in the U.S. stockpile of unitary chemical munitions. Congress has mandated the destruction of these agents, which is currently slated for completion in 2004. The acute, chronic, and delayed toxicity of these agents is reviewed in this analysis. The largely negative results from studies of genotoxicity, carcinogenicity, developmental, and reproductive toxicity are also presented. Nerve agents show few or delayed effects. At supralethal doses, GB can cause delayed neuropathy in antidote-protected chickens, but there is no evidence that it causes this syndrome in humans at any dose. Agent VX shows no potential for inducing delayed neuropathy in any species. In view of their lack of genotoxcity, the nerve agents are not likely to be carcinogens. The overreaching concern with regard to nerve agent exposure is the extraordinarily high acute toxicity of these substances. Furthermore, acute effects of moderate exposure such as nausea, diarrhea, inability to perform simple mental tasks, and respiratory effects may render the public unable to respond adequately to emergency instructions in the unlikely event of agent releaase, making early warning and exposure avoidance important. Likewise, exposure or self-contamination of first responders and medical personnel must be avoided. Control limits for exposure via surface contact of drinking water are needed, as are detection methods for low levels in water or foodstuffs. Images Figure 2. PMID:9719666

  12. Toxicity of the organophosphate chemical warfare agents GA, GB, and VX: implications for public protection.

    PubMed

    Munro, N

    1994-01-01

    The nerve agents, GA, GB, and VX are organophosphorus esters that form a major portion of the total agent volume contained in the U.S. stockpile of unitary chemical munitions. Congress has mandated the destruction of these agents, which is currently slated for completion in 2004. The acute, chronic, and delayed toxicity of these agents is reviewed in this analysis. The largely negative results from studies of genotoxicity, carcinogenicity, developmental, and reproductive toxicity are also presented. Nerve agents show few or delayed effects. At supralethal doses, GB can cause delayed neuropathy in antidote-protected chickens, but there is no evidence that it causes this syndrome in humans at any dose. Agent VX shows no potential for inducing delayed neuropathy in any species. In view of their lack of genotoxicity, the nerve agents are not likely to be carcinogens. The overreaching concern with regard to nerve agent exposure is the extraordinarily high acute toxicity of these substances. Furthermore, acute effects of moderate exposure such as nausea, diarrhea, inability to perform simple mental tasks, and respiratory effects may render the public unable to respond adequately to emergency instructions in the unlikely event of agent release, making early warning and exposure avoidance important. Likewise, exposure or self-contamination of first responders and medical personnel must be avoided. Control limits for exposure via surface contact of drinking water are needed, as are detection methods for low levels in water or foodstuffs. PMID:9719666

  13. Toxicity of vesicant agents scheduled for destruction by the chemical stockpile disposal program

    SciTech Connect

    Watson, A.P.; Griffin, G.D. )

    1992-11-01

    The vesicant agents of the unitary chemical munitions stockpile include various formulations of sulfur mustard [bis-(2-chloroethyl) sulfide; agents H, HD, and HT] and small quantities of the organic arsenical Lewisite [dichloro(2-chlorovinyl)arsine; agent L]. These agents can be dispersed in liquid, aerosol, or vapor form and are capable of producing severe chemical burns upon direct contact with tissue. Moist tissues such as the eyes, respiratory tract, and axillary areas are particularly affected. Available data summarizing acute dose response in humans and laboratory animals are summarized. Vesicant agents are also capable of generating delayed effects such as chronic bronchitis, carcinogenesis, or keratitis/keratopathy of the eye under appropriate conditions of exposure and dose. These effects may not become manifest until years following exposure. Risk analysis derived from carcinogenesis data indicates that sulfur mustard possesses a carcinogenic potency similar to that of benzo[a]pyrene. Because mustard agents are alkylating compounds, they destroy individual cells by reaction with cellular proteins, enzymes, RNA, and DNA. Once begun, tissue reaction is irreversible. Mustard agents are mutagenic; data for cellular and laboratory animal assays are presented. Reproductive effects have not been demonstrated in the offspring of laboratory rats. Acute Lewisite exposure has been implicated in cases of Bowen's disease, an intraepidermal squamous cell carcinoma. Lewisite is not known to generate reproductive or teratogenic effects. 112 refs., 1 fig., 6 tabs.

  14. Toxicity of vesicant agents scheduled for destruction by the Chemical Stockpile Disposal Program.

    PubMed

    Watson, A P; Griffin, G D

    1992-11-01

    The vesicant agents of the unitary chemical munitions stockpile include various formulations of sulfur mustard [bis-(2-chloroethyl) sulfide; agents H, HD, and HT] and small quantities of the organic arsenical Lewisite [dichloro(2-chlorovinyl) arsine; agent L]. These agents can be dispersed in liquid, aerosol, or vapor form and are capable of producing severe chemical burns upon direct contact with tissue. Moist tissues such as the eyes, respiratory tract, and axillary areas are particularly affected. Available data summarizing acute dose response in humans and laboratory animals are summarized. Vesicant agents are also capable of generating delayed effects such as chronic bronchitis, carcinogenesis, or keratitis/keratopathy of the eye under appropriate conditions of exposure and dose. These effects may not become manifest until years following exposure. Risk analysis derived from carcinogenesis data indicates that sulfur mustard possesses a carcinogenic potency similar to that of benzo[a]pyrene. Because mustard agents are alkylating compounds, they destroy individual cells by reaction with cellular proteins, enzymes, RNA, and DNA. Once begun, tissue reaction is irreversible. Mustard agents are mutagenic; data for cellular and laboratory animal assays are presented. Reproductive effects have not been demonstrated in the offspring of laboratory rats. Acute Lewisite exposure has been implicated in cases of Bowen's disease, an intraepidermal squamous cell carcinoma. Lewisite is not known to generate reproductive or teratogenic effects. PMID:1486858

  15. Toxicity of vesicant agents scheduled for destruction by the Chemical Stockpile Disposal Program.

    PubMed Central

    Watson, A P; Griffin, G D

    1992-01-01

    The vesicant agents of the unitary chemical munitions stockpile include various formulations of sulfur mustard [bis-(2-chloroethyl) sulfide; agents H, HD, and HT] and small quantities of the organic arsenical Lewisite [dichloro(2-chlorovinyl) arsine; agent L]. These agents can be dispersed in liquid, aerosol, or vapor form and are capable of producing severe chemical burns upon direct contact with tissue. Moist tissues such as the eyes, respiratory tract, and axillary areas are particularly affected. Available data summarizing acute dose response in humans and laboratory animals are summarized. Vesicant agents are also capable of generating delayed effects such as chronic bronchitis, carcinogenesis, or keratitis/keratopathy of the eye under appropriate conditions of exposure and dose. These effects may not become manifest until years following exposure. Risk analysis derived from carcinogenesis data indicates that sulfur mustard possesses a carcinogenic potency similar to that of benzo[a]pyrene. Because mustard agents are alkylating compounds, they destroy individual cells by reaction with cellular proteins, enzymes, RNA, and DNA. Once begun, tissue reaction is irreversible. Mustard agents are mutagenic; data for cellular and laboratory animal assays are presented. Reproductive effects have not been demonstrated in the offspring of laboratory rats. Acute Lewisite exposure has been implicated in cases of Bowen's disease, an intraepidermal squamous cell carcinoma. Lewisite is not known to generate reproductive or teratogenic effects. PMID:1486858

  16. Tissue-based water quality biosensors for detecting chemical warfare agents

    DOEpatents

    Greenbaum, Elias; Sanders, Charlene A.

    2003-05-27

    A water quality sensor for detecting the presence of at least one chemical or biological warfare agent includes: a cell; apparatus for introducing water into the cell and discharging water from the cell adapted for analyzing photosynthetic activity of naturally occurring, free-living, indigenous photosynthetic organisms in water; a fluorometer for measuring photosynthetic activity of naturally occurring, free-living, indigenous photosynthetic organisms drawn into the cell; and an electronics package that analyzes raw data from the fluorometer and emits a signal indicating the presence of at least one chemical or biological warfare agent in the water.

  17. Method and apparatus for the gas phase decontamination of chemical and biological agents

    DOEpatents

    O'Neill, Hugh J.; Brubaker, Kenneth L.

    2003-10-07

    An apparatus and method for decontaminating chemical and biological agents using the reactive properties of both the single atomic oxygen and the hydroxyl radical for the decontamination of chemical and biological agents. The apparatus is self contained and portable and allows for the application of gas reactants directly at the required decontamination point. The system provides for the use of ultraviolet light of a specific spectral range to photolytically break down ozone into molecular oxygen and hydroxyl radicals where some of the molecular oxygen is in the first excited state. The excited molecular oxygen will combine with water vapor to produce two hydroxyl radicals.

  18. Laboratory conditions and safety in a chemical warfare agent analysis and research laboratory.

    PubMed

    Kenar, Levent; Karayilanoğlu, Turan; Kose, Songul

    2002-08-01

    Toxic chemicals have been used as weapons of war and also as means of terrorist attacks on civilian populations. Research focusing on chemical warfare agents (CWAs) may be associated with an increased risk of exposure to and contamination by these agents. This article summarizes some of the regulations concerning designation and safety in a CWA analysis and research laboratory and medical countermeasures in case of an accidental exposure. The design of such a laboratory, coupled with a set of safety guidelines, provides for the safe conduct of research and studies involving CWAs. Thus, a discussion of decontamination and protection means against CWAs is also presented. PMID:12188231

  19. Micro-Radiography of Living Biological Organisms with MEDIPIX2 Detector and Application of Various Contrast Agents

    NASA Astrophysics Data System (ADS)

    Dammer, Jiri; Sopko, Vit; Jakubek, Jan; Weyda, Frantisek; Benes, Jiri; Zahorovsky, Julian

    2012-08-01

    We describe a newly developed radiographic system equipped with Medipix2 semiconductor pixel detector and a micro-focus FeinFocus X-ray tube tabletop. The detector is used as an imager that counts individual photons of ionizing radiation, emitted by the X-ray tube. The digital pixel detectors of the Medipix family represent a highly efficient type of imaging devices with high spatial resolution better than 1μm, and unlimited dynamic range allowing single particle of radiation and to determine their energies. The setup is particularly suitable for radiographic imaging of small biological samples, including in vivo observations with various contrast agents (iodine and lanthanum nitrate). Along with the description of the apparatus we provide examples of application of iodine and lanthanum nitrate contrast agents as tracers in various insects as model organisms. The iodine contrast agent increases the absorption of X-rays and this leads to better resolution of internal structures of biological organisms, and especially the various cavities, pores, etc. Micro-radiographic imaging helps to detect organisms living in a not visible environment, visualize internal biological processes and also to resolve the details of their body (morphology). Tiny live insects are an ideal object for our studies.

  20. Zeolite fiber integrated microsensors for highly sensitive point detection of chemical agents

    NASA Astrophysics Data System (ADS)

    Liu, Ning; Hui, Juan; Dong, Junhang; Xiao, Hai

    2006-05-01

    A zeolite-fiber integrated chemical sensor was developed for in situ point detection of chemical warfare agents. The sensor was made by fine-polishing the MFI polycrystalline zeolite thin film synthesized on the endface of the single mode optical fiber. The sensor device operates by measuring the optical thickness changes of the zeolite thin film caused by the adsorption of analytes into the zeolite channels. The sensor was demonstrated for sensitive detection of toluene and dimethyl methylphosphonate (DMMP).

  1. Chemical warfare nerve agents. A review of cardiopulmonary pathophysiology and resuscitation. Technical report

    SciTech Connect

    Franz, D.R.

    1986-12-01

    The purpose of this document is to provide the medical research community with a digest of the open and internal literature related to cardiopulmonary pathophysiology, resuscitation, and animal modeling of chemical warfare nerve agent intoxication. Though not comprehensive, this review makes available to the reader a cross section of what research was done in this small but important part of the medical chemical defense research program between World War II and the early 1980's.

  2. Toxicity of the organophosphate chemical warfare agents GA, GB, and VX: Implications for public protection

    SciTech Connect

    Munro, N.B.; Ambrose, K.R.; Watson, A.P. )

    1994-01-01

    The nerve agents, GA, GB, and VX are organophosphorus esters that form a major portion of the total agent volume contained in the U.S. stockpile of unitary chemical munitions. Congress has mandated the destruction of these agents, which is currently slated for completion in 2004. The acute, chronic, and delayed toxicity of these agents is reviewed in this analysis. The largely negative results from studies of genotoxicity, carcinogenicity, developmental, and reproductive toxicity are also presented. Nerve agents show few or delayed effects. At supralethal doses, GB can cause delayed neuropathy in antidote-protected chickens, but there is not evidence that it causes this syndrome in humans at any dose. Agent VX shows no potential for inducing delayed neuropathy in any species. In view of their lack of genotoxicity, the nerve agent exposure is the extraordinarily high acute toxicity of these substances. Futhermore, acute effects of moderate exposure such as nausea, diarrhea, inability to perform simple mental tasks, and respiratory effects may render the public unable to respond adequately to emergency instructions in the unlikely event of agent release, making early warning and exposure avoidance important. Likewise, exposure or self-contamination of first responders and medical personnel must be avoided. Control limits for exposure via surface contact of drinking water are needed, as are detection methods for low levels in water or foodstuffs. 187 refs., 3 figs., 7 tabs.

  3. Fate of sessile droplet chemical agents in environmental substrates in the presence of physiochemical processes

    NASA Astrophysics Data System (ADS)

    Navaz, H. K.; Dang, A. L.; Atkinson, T.; Zand, A.; Nowakowski, A.; Kamensky, K.

    2014-05-01

    A general-purpose multi-phase and multi-component computer model capable of solving the complex problems encountered in the agent substrate interaction is developed. The model solves the transient and time-accurate mass and momentum governing equations in a three dimensional space. The provisions for considering all the inter-phase activities (solidification, evaporation, condensation, etc.) are included in the model. The chemical reactions among all phases are allowed and the products of the existing chemical reactions in all three phases are possible. The impact of chemical reaction products on the transport properties in porous media such as porosity, capillary pressure, and permeability is considered. Numerous validations for simulants, agents, and pesticides with laboratory and open air data are presented. Results for chemical reactions in the presence of pre-existing water in porous materials such as moisture, or separated agent and water droplets on porous substrates are presented. The model will greatly enhance the capabilities in predicting the level of threat after any chemical such as Toxic Industrial Chemicals (TICs) and Toxic Industrial Materials (TIMs) release on environmental substrates. The model's generality makes it suitable for both defense and pharmaceutical applications.

  4. Applications of LPG fiber optical sensors for relative humidity and chemical-warfare-agents monitoring

    NASA Astrophysics Data System (ADS)

    Luo, Shufang; Liu, Yongcheng; Sucheta, Artur; Evans, Mishell K.; Van Tassell, Roger

    2002-09-01

    A long-period grating (LPG) fiber optic sensor has been developed for monitoring the relative humidity levels and toxic chemicals, especially the chemical warfare agents. The principle of operation of this sensor is based on monitoring the refractive index changes exhibited by the reactive coating applied to the surface of the LPG region in response to analytes. Specific interaction of the analyte with the thin film polymer coating produces as the output a wavelength shift that can be correlated with the concentration of the analyte. Thin polymer coating for relative humidity sensor is made of carboxymethylcellulose (CMC) covalently bound to the surface of the fiber. Coating for chemical warfare agent detection employs metal nanoclusters imbedded in polyethylenimine (PEI) for specific reaction. The relative humidity level can be determined from 0% to 95% and the level of toxic chemicals can be determined is at least on the scale of 1 ppm. This small-size and low-cost LPG fiber optic sensor exhibited high sensitivity, rapid response, repeatability and durability. The goal of developing relative humidity sensor is to produce a fiber optic sensor-based health monitoring system for building, while the chemical sensor has found its application in point detection network for chemical warfare agent monitoring.

  5. Compilation of existing chemical agent guidelines table as of September 1997

    SciTech Connect

    Foust, C.B.

    1998-08-01

    Public Law 99-145 requires the US Department of the Army to dispose of the lethal chemical agents and munitions stockpile stored at eight Army installations throughout the continental US and Johnston Atoll in the Pacific. Recognition by the US Army that a potential threat to the public from continued storage was greater than the threat from transportation and demilitarization of chemical agents gave rise to the Chemical Stockpile Emergency Preparedness Program (CSEPP). CSEPP is a community emergency preparedness program complementing the Department of Defense`s initiative to destroy domestic stockpiles of aged chemical warfare agent munitions. The Federal Emergency Management Agency (FEMA) and the US Army jointly coordinate and direct the CSEPP. The Compilation of Existing Chemical Agent Guidelines Table was developed under the direction of FEMA and the US Army Center for Health Promotion and Preventive Medicine (USACHPPM). The purpose of this Table is to identify established chemical warfare agent guidelines, standards, and interim standards as of September 1997, and place them in an explanatory context for ready use by the CSEPP community. This Table summarizes and organizes information from numerous agencies and review bodies responsible for recommending exposure guidelines [e.g., The Centers for Disease Control and Prevention (CDC), Committee on Toxicology (COT), Environmental Protection Agency (EPA), FEMA, Army and other federal agencies]. This Table provides references for the interested reader, but does not provide data and assumptions on which exposure guidelines were based, or comment on the rationale or appropriateness of the given values. To do so is beyond the scope of work for this task.

  6. Chemical agent standoff detection and identification with a hyperspectral imaging infrared sensor

    NASA Astrophysics Data System (ADS)

    Lagueux, Philippe; Vallières, Alexandre; Villemaire, André; Chamberland, Martin; Farley, Vincent; Giroux, Jean

    2009-09-01

    Standoff detection, identification and quantification of chemical agents are fundamental needs in several fields of applications. Additional required sensor characteristics include high sensitivity, low false alarms and high-speed (ideally real-time) operation, all in a compact and robust package. The thermal infrared portion of the electromagnetic spectrum has been utilized to implement such chemical sensors, either with spectrometers (with none or moderate imaging capability) or with imagers (with moderate spectral capability). Only with the recent emergence of high-speed, large format infrared imaging arrays, has it been possible to design chemical sensors offering uncompromising performance in the spectral, spatial, as well as the temporal domain. Telops has developed an innovative instrument that can not only provide an early warning for chemical agents and toxic chemicals, but also one that provides a "Chemical Map" in the field of view. To provide to best field imaging spectroscopy instrument, Telops has developed the FIRST, Field-portable Imaging Radiometric Spectrometer Technology, instrument. This instrument is based on a modular design that includes: a high-performance infrared FPA and data acquisition electronics, onboard data processing electronics, a high-performance Fourier transform modulator, dual integrated radiometric calibration targets and a visible boresight camera. These modules, assembled together in an environmentally robust structure, used in combination with Telops' proven radiometric and spectral calibration algorithms make this instrument a world-class passive standoff detection system for chemical imaging. This paper presents chemical detection and identification results obtained with the FIRST sensor.

  7. 32 CFR 174.16 - Real property containing explosive or chemical agent hazards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 1 2014-07-01 2014-07-01 false Real property containing explosive or chemical agent hazards. 174.16 Section 174.16 National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE CLOSURES AND REALIGNMENT REVITALIZING BASE CLOSURE COMMUNITIES AND ADDRESSING IMPACTS OF REALIGNMENT Environmental Matters § 174.16...

  8. Inactivation of Recombinant Bacteriophage Lambda by Use of Chemical Agents and UV Radiation

    PubMed Central

    Clark, Ewan M.; Wright, Harry; Lennon, Kelly-Anne; Craik, Vicki A.; Clark, Jason R.

    2012-01-01

    Several approaches for the inactivation of bacteriophage lambda, including UV germicidal irradiation (UVGI) and the chemical agents Virkon-S, Chloros, Decon-90, and sodium hydroxide (NaOH), were compared. Virkon, NaOH, and UVGI caused a ≥7-log10 reduction in phage titers. This study successfully describes several methods with potential for bacteriophage inactivation in industrial settings. PMID:22327583

  9. Fourier transform microwave spectroscopy of chemical-warfare agents and their synthetic precursors

    NASA Astrophysics Data System (ADS)

    Hight Walker, Angela R.; Suenram, Richard D.; Samuels, Alan C.; Jensen, James O.; Woolard, Dwight L.; Wiebach, W.

    1999-01-01

    Fourier-transform microwave (FTMW) spectroscopy is an established is an established technique for observing the rotational spectra of molecules and complexes in molecular beams. Scientists at the National Institute of Standards and Technology (NIST) are adapting this measurement technology for applications in analytical chemistry. Presently, FTMW spectroscopy is being used to investigate chemical-warfare agents and their synthetic precursors. A FTMW spectroscopy facility has been established at a surety laboratory at the Edgewood Research, Development, and Engineering Center, where the capabilities exist for handling these deadly warfare agents. Here, the rotational spectra of Sarin, Soman and DF have been observed and assigned. Also, microwave spectroscopic studies of less toxic precursors such as pinacolyl alcohol, isopropyl alcohol, and thiodiglycol have been carried out at NIST. Tests will be undertaken to assess the potential of using FTMW spectroscopy for detecting trace amounts of chemical-warfare agents and precursors in air. A database of rotational transition frequencies is being compiled for use in conjunction with a FTMW spectrometer to unambiguously detect and monitor chemical weapons. The sensitivity and resolution of FTMW spectroscopy of FTMW spectroscopy suggest that the technique may offer real-time, unequivocal identification of chemical-warfare agents at trace vapor concentrations in air.

  10. DESI-MS/MS of Chemical Warfare Agents and Related Compounds

    NASA Astrophysics Data System (ADS)

    D'Agostino, Paul A.

    Solid phase microextraction (SPME) fibers were used to headspace ­sample chemical warfare agents and their hydrolysis products from glass vials and glass vials containing spiked media, including Dacron swabs, office carpet, paper and fabric. The interface of the Z-spray source was modified to permit safe introduction of the SPME fibers for desorption electrospray ionization mass spectrometric (DESI-MS) analysis. A "dip and shoot" method was also developed for the rapid sampling and DESI-MS analysis of chemical warfare agents and their hydrolysis products in liquid samples. Sampling was performed by simply dipping fused silica, stainless steel or SPME tips into the organic or aqueous samples. Replicate analyses were completed within several minutes under ambient conditions with no sample pre-treatment, resulting in a significant increase in sample throughput. The developed sample handling and analysis method was applied to the determination of chemical warfare agent content in samples containing unknown chemical and/or biological warfare agents. Ottawa sand was spiked with sulfur mustard, extracted with water and autoclaved to ensure sterility. Sulfur mustard was completely hydrolysed during the extraction/autoclave step and thiodiglycol was identified by DESI-MS, with analyses generally being completed within 1 min using the "dip and shoot" method.

  11. Laser-based instrumentation for detection of chemical-warfare agents

    SciTech Connect

    Quigley, G.P.; Radziemski, L.J.; Sander, R.K.; Hartford, A. Jr.

    1981-01-01

    Several laser-based techniques are being developed for remote, point, and surface contamination detection of chemical warfare agents. These techniques include optoacoustic spectroscopy, laser-induced breakdown spectroscopy, and synchronous detection of laser-induced fluorescence. Detection limits in the part-per-million to part-per-billion regime have been demonstrated.

  12. Ultrasensitive detection of explosives and chemical warfare agents by low-pressure photoionization mass spectrometry.

    PubMed

    Sun, Wanqi; Liang, Miao; Li, Zhen; Shu, Jinian; Yang, Bo; Xu, Ce; Zou, Yao

    2016-08-15

    On-spot monitoring of threat agents needs high sensitive instrument. In this study, a low-pressure photoionization mass spectrometer (LPPI-MS) was employed to detect trace amounts of vapor-phase explosives and chemical warfare agent mimetics under ambient conditions. Under 10-s detection time, the limits of detection of 2,4-dinitrotoluene, nitrotoluene, nitrobenzene, and dimethyl methyl phosphonate were 30, 0.5, 4, and 1 parts per trillion by volume, respectively. As compared to those obtained previously with PI mass spectrometric techniques, an improvement of 3-4 orders of magnitude was achieved. This study indicates that LPPI-MS will open new opportunities for the sensitive detection of explosives and chemical warfare agents. PMID:27260452

  13. Development of Single Crystal Chemical Vapor Deposition Diamonds for Detector Applications

    SciTech Connect

    Kagan, Harris; Kass, Richard; Gan, K. K.

    2014-01-23

    With the LHC upgrades in 2013, and further LHC upgrades scheduled in 2018, most LHC experiments are planning for detector upgrades which require more radiation hard technologies than presently available. At present all LHC experiments now have some form of diamond detector. As a result Chemical Vapor Deposition (CVD) diamond has now been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of all LHC experiments. Moreover CVD diamond is now being discussed as an alternative sensor material for tracking very close to the interaction region of the HL-LHC where the most extreme radiation conditions will exist. Our work addressed the further development of the new material, single-crystal Chemical Vapor Deposition diamond, towards reliable industrial production of large pieces and new geometries needed for detector applications. Our accomplishments include: • Developed a two U.S.companies to produce electronic grade diamond, • Worked with companies and acquired large area diamond pieces, • Performed radiation hardness tests using various proton energies: 70 MeV (Cyric, Japan), 800 MeV (Los Alamos), and 24 GeV (CERN).

  14. Chemical Agents

    MedlinePlus

    ... glycol Hydrazine Hydrofluoric acid Hydrogen chloride Lewisite Melamine Mercury Methyl bromide Methyl isocyanate Nicotine Nitrogen mustard Opioids ... L-3) Long-acting anticoagulant (super warfarin) M Mercury Methyl bromide Methyl isocyanate Mustard gas (H) (sulfur ...

  15. Chemical warfare agent detection in complex environments with comprehensive two-dimensional gas chromatography

    NASA Astrophysics Data System (ADS)

    Reichenbach, Stephen E.; Ni, Mingtian; Kottapalli, Visweswara; Visvanathan, Arvind; Ledford, Edward B., Jr.; Oostdijk, John; Trap, Henk C.

    2003-08-01

    Comprehensive two-dimensional gas chromatography (GCxGC) is an emerging technology for chemical separation that provides an order-of-magnitude increase in separation capacity over traditional gas chromatography. GCxGC separates chemical species with two capillary columns interfaced by two-stage thermal desorption. Because GCxGC is comprehensive and has high separation capacity, it can perform multiple traditional analytical methods with a single analysis. GCxGC has great potential for a wide variety of environmental sensing applications, including detection of chemical warfare agents (CWA) and other harmful chemicals. This paper demonstrates separation of nerve agents sarin and soman from a matrix of gasoline and diesel fuel. Using a combination of an initial column separating on the basis of boiling point and a second column separating on the basis of polarity, GCxGC clearly separates the nerve agents from the thousands of other chemicals in the sample. The GCxGC data is visualized, processed, and analyzed as a two-dimensional digital image using a software system for GCxGC image processing developed at the University of Nebraska - Lincoln.

  16. Handheld dual-wavelength Raman instrument for the detection of chemical agents and explosives

    NASA Astrophysics Data System (ADS)

    Christesen, Steven D.; Guicheteau, Jason A.; Curtiss, Justin M.; Fountain, Augustus W.

    2016-07-01

    Handheld Raman systems have become powerful analytical tools for the detection and identification of hazardous chemical materials that are now commonly used by both the civilian and military communities. Due to the availability of compact lasers and sensitive detectors, systems typically operate at 785 nm. However, the Raman return at this wavelength can still be obscured by fluorescent impurities in the targeted materials or their matrices. To potentially mitigate this shortcoming, a prototype dual-wavelength Raman incorporating both 785- and 1064-nm excitations was developed and assessed at the Edgewood Chemical Biological Center. The results of that evaluation are discussed here.

  17. Portable Raman device for detection of chemical and biological warfare agents

    NASA Astrophysics Data System (ADS)

    Wabuyele, Musundi B.; Martin, Matthew E.; Yan, Fei; Stokes, David L.; Mobley, Joel; Cullum, Brian M.; Wintenberg, Alan; Lenarduzzi, Roberto; Vo-Dinh, Tuan

    2005-04-01

    This paper describes a compact, self-contained, cost effective, and portable Raman Integrated Tunable Sensor (RAMiTs) for screening a wide variety of chemical and biological agents for homeland defense applications. The instrument is a fully-integrated, tunable, "point-and-shoot" Raman monitor based on solid-state acousto-optic tunable filter (AOTF) technology. It can provide direct identification and quantitative analysis of chemical and biological samples in a few seconds under field conditions. It also consists of a 830-nm diode laser for excitation, and an avalanche photodiode for detection. Evaluation of this instrument has been performed by analyzing several standard samples and comparing the results those obtained using a conventional Raman system. In addition to system evaluation, this paper will also discuss potential applications of the RAMiTs for detection of chemical and biological warfare agents.

  18. Chemistry of destroying chemical warfare agents in flame. Technical project report, April 1994-May 1995

    SciTech Connect

    Korobeinichev, O.P.; Chernov, A.A.; Shvartsberg, V.M.; Il`in, S.B.; Mokrushin, V.V.

    1995-05-01

    The goal of the research is to increase our understanding of flame chemistry of organophosphorus compounds (OPC). This class of chemicals includes chemical warfare agents. (CWAs) such as the nerve agents GB GD and VX, stockpiles of which in the United States and Former Soviet Union are scheduled for destruction by incineration or other technologies. Although high CWA destruction efficiency has been demonstrated in incinerator tests in the U.S. it is necessary to improve technology for achievement higher efficiency and lower level of pollutants. The knowledge of detailed destruction chemistry of the CWA and simulants can be obtained by studying the structure of flames, doped with simulants and CWA and by the development of the combustion model which will include the chemical mechanism of destroying CWA in flame. Alkyl phosphates and alkyl phosphonates are typical organophosphorus compounds, that are simulants of sarin.

  19. Determination of trace amounts of chemical warfare agent degradation products in decontamination solutions with NMR spectroscopy.

    PubMed

    Koskela, Harri; Rapinoja, Marja-Leena; Kuitunen, Marja-Leena; Vanninen, Paula

    2007-12-01

    Decontamination solutions are used for an efficient detoxification of chemical warfare agents (CWAs). As these solutions can be composed of strong alkaline chemicals with hydrolyzing and oxidizing properties, the analysis of CWA degradation products in trace levels from these solutions imposes a challenge for any analytical technique. Here, we present results of application of nuclear magnetic resonance spectroscopy for analysis of trace amounts of CWA degradation products in several untreated decontamination solutions. Degradation products of the nerve agents sarin, soman, and VX were selectively monitored with substantially reduced interference of background signals by 1D 1H-31P heteronuclear single quantum coherence (HSQC) spectrometry. The detection limit of the chemicals was at the low part-per-million level (2-10 microg/mL) in all studied solutions. In addition, the concentration of the degradation products was obtained with sufficient confidence with external standards. PMID:17973498

  20. [Determination of fluorescent whitening agents in plastic food contact materials by high performance liquid chromatography with fluorescence detector].

    PubMed

    Jiao, Yanna; Ding, Li; Zhu, Shaohua; Fu, Shanliang; Gong, Qiang; Li, Hui; Wang, Libing

    2013-01-01

    A method for the determination of fluorescent whitening agents in plastic food contact materials by high performance liquid chromatography (HPLC) with fluorescence detector was developed. The samples were extracted with trichloromethane by sonication for 30 min at 40 degrees C. The HPLC method was performed on a column of Eclipse XDB-C18 (250 mm x 4.6 mm, 5 microm) by gradient elution using 5 mmol/L ammonium acetate and acetonitrile as the mobile phases, and detected by the fluorescence detector at an excitation wavelength of 350 nm and an emission wavelength of 430 nm. The experimental results indicated that the four fluorescent whitening agents were separated well. The limits of detection (LOD) (S/N = 3) were 0.3, 0.1, 0.05, 0.14 mg/L, and the limits of quantification (LOQ) (S/N = 10) were 1.0, 0.4, 0.2, 0.5 mg/L for 1,4-bis (4-cyanostyryl) benzene (C. I. 199), 1,4-bis (2-benzoxazolyl) naphthalene (C. I. 367), 4,4'-bis(2-methoxystyryl) biphenyl (C. I. 378) and 2,5-thiophenediylbis (5-tert-butyl-1,3-benzoxazole) (C. I. 184), respectively. Good linearities with correlation coefficients (r2) not less than 0.991 were obtained. The proposed method is simple, accurate, sensitive and can meet the requirements of the routine determination of fluorescent whitening agents in entry-exit products. PMID:23667995

  1. Reevaluation of 1999 Health-Based Environmental Screening Levels (HBESLs) for Chemical Warfare Agents

    SciTech Connect

    Watson, Annetta Paule; Dolislager, Fredrick G

    2007-05-01

    This report evaluates whether new information and updated scientific models require that changes be made to previously published health-based environmental soil screening levels (HBESLs) and associated environmental fate/breakdown information for chemical warfare agents (USACHPPM 1999). Specifically, the present evaluation describes and compares changes that have been made since 1999 to U.S. Environmental Protection Agency (EPA) risk assessment models, EPA exposure assumptions, as well as to specific chemical warfare agent parameters (e.g., toxicity values). Comparison was made between screening value estimates recalculated with current assumptions and earlier health-based environmental screening levels presented in 1999. The chemical warfare agents evaluated include the G-series and VX nerve agents and the vesicants sulfur mustard (agent HD) and Lewisite (agent L). In addition, key degradation products of these agents were also evaluated. Study findings indicate that the combined effect of updates and/or changes to EPA risk models, EPA default exposure parameters, and certain chemical warfare agent toxicity criteria does not result in significant alteration to the USACHPPM (1999) health-based environmental screening level estimates for the G-series and VX nerve agents or the vesicant agents HD and L. Given that EPA's final position on separate Tier 1 screening levels for indoor and outdoor worker screening assessments has not yet been released as of May 2007, the study authors find that the 1999 screening level estimates (see Table ES.1) are still appropriate and protective for screening residential as well as nonresidential sites. As such, risk management decisions made on the basis of USACHPPM (1999) recommendations do not require reconsideration. While the 1999 HBESL values are appropriate for continued use as general screening criteria, the updated '2007' estimates (presented below) that follow the new EPA protocols currently under development are also

  2. Disposal of chemical agents and munitions stored at Pine Bluff Arsenal, Pine Bluff, Arkansas

    SciTech Connect

    Ensminger, J.T.; Hillsman, E.L.; Johnson, R.D.; Morrisey, J.A.; Staub, W.P.; Boston, C.R.; Hunsaker, D.B.; Leibsch, E.; Rickert, L.W.; Tolbert, V.R.; Zimmerman, G.P.

    1991-09-01

    The Pine Bluff Arsenal (PBA) near Pine Bluff, Arkansas, is one of eight continental United States (CONUS) Army installations where lethal unitary chemical agents and munitions are stored and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at PBA consists of approximately 12%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts). The purpose of this report is to examine the proposed implementation of on-site disposal at PBA in light of more recent and more detailed data than those on which the FPEIS is based. New population data were used to compute fatalities using the same computation methods and values for all other parameters as in the FPEIS. Results indicate that all alternatives are indistinguishable when the potential health impacts to the PBA community are considered. However, risks from on-site disposal are in all cases equal to or less than risks from other alternatives. Furthermore, no unique resources with the potential to prevent or delay implementation of on-site disposal at PBA have been identified.

  3. Synergic effect of chelating agent and oxidant on chemical mechanical planarization

    NASA Astrophysics Data System (ADS)

    Weijuan, Liu; Yuling, Liu

    2015-02-01

    Chemically dominant alkaline slurry, which is free of BTA (benzotriazole) and other inhibitors, was investigated. The synergic effect of the chelating agent and oxidant on the chemical mechanical planarization (CMP) was taken into consideration. Copper CMP slurry is mainly composed of an oxidizer, nonionic surfactant, chelating agent and abrasive particles. The effect of different synergic ratios of oxidant with chelating agent on the polishing removal rate, static etch rate and planarization were detected. The planarization results reveal that with the increase of oxidant concentration, the dishing value firstly diminished and then increased again. When the synergic ratios is 3, the dishing increases the least. A theoretical model combined with chemical-mechanical kinetics process was proposed in the investigation, which can explain this phenomenon. Based on the theoretical model, the effect of synergic ratios of oxidant with chelating agent on velocity D-value (convex removal rate minus recessed removal rate) was analyzed. The results illustrate that when the synergic ratio is between 2.5-3.5, the velocity D-value is relatively higher, thereby good planarization can be achieved in this interval. This investigation provides a new guide to analyze and study copper line corrosion in the recessed region during copper clearing polishing.

  4. [Analytical and on-site detection methods for chemical warfare agents].

    PubMed

    Seto, Yasuo

    2006-12-01

    Chemical warfare agents (CWAs) are fast acting and sometimes lethal, even at low levels, and can be classified into nerve gases, blister agents, choking agents, blood agents, vomit agents, tear gases, and incapacitating agents. As countermeasures against CWA terrorism, detection and identification are important. In crisis management, monitoring of CWAs in public places and security checks at territorial borders, big event venues, and executive facilities are performed for protection against terrorism. In consequence management, on-site detection by first responders and laboratory analysis after on-site sampling and transfer are performed for minimization of terrorism damage, leading to personal protection, initial investigation, and emergency lifesaving. In incident management, laboratory analysis is performed to provide evidence at court trials for the prevention of future crimes. Laboratory analysis consists of pretreatment of on-site and casualty samples and instrumental analysis using GC-MS. However, CWAs are easily degraded, and thus are difficult to detect. Instead, it is useful to detect their metabolites and degradation products using tert-butyldimethylsilyl derivatization GC-MS or direct LC-MS. Commercially available chemical detection equipment such as gas detection tubes and ion mobility spectrometers are used for on-site detection. We have evaluated the detection performance of such equipment and found that no equipment fulfills the required perfect performance of CWA detection sensitivity, accuracy, response time, return time, and operation. To overcome the drawbacks, we have adopted the monitoring tape method and counterflow introduction atmospheric pressure chemical ionization mass spectrometry and recommend the combination of commercial detection equipment and these new technologies for simultaneous, rapid detection of all CWAs. PMID:17139154

  5. High-sensitivity, high-selectivity detection of chemical warfare agents

    NASA Astrophysics Data System (ADS)

    Pushkarsky, Michael B.; Webber, Michael E.; Macdonald, Tyson; Patel, C. Kumar N.

    2006-01-01

    We report high-sensitivity detection of chemical warfare agents (nerve gases) with very low probability of false positives (PFP). We demonstrate a detection threshold of 1.2ppb (7.7μg/m3 equivalent of Sarin) with a PFP of <1:106 in the presence of many interfering gases present in an urban environment through the detection of diisopropyl methylphosphonate, an accepted relatively harmless surrogate for the nerve agents. For the current measurement time of ˜60s, a PFP of 1:106 corresponds to one false alarm approximately every 23months. The demonstrated performance satisfies most current homeland and military security requirements.

  6. Supercritical fluid extraction and organic solvent microextraction of chemical agent simulants from soil

    SciTech Connect

    Griest, W.H.; Ramsey, R.S.; Ho, C.h.; Caldwell, W.M.

    1991-12-31

    Experiments with chemical warfare agent simulants suggest that supercritical fluid extraction can achieve good extraction recoveries of agents in soil and produce less laboratory waste than current organic solvent extraction methods. Two-ppm spikes in 1 g of Rocky Mountain Arsenal Standard Soil were extracted using 5% methanol in carbon dioxide at 300 atm for 2 min at 60{degrees}C. Recoveries (n=3) were 79{plus_minus}23% for dimethylmethylphosphonate, 93{plus_minus}14% for 2-chlorethylethylsulfide, 92{plus_minus}13% for diisopropylfluorophosphate, and 95{plus_minus}17% for diisopropylmethylphosphonate. A 5 min ultrasonic micro-scale extraction using methanol is more reproducible but less efficient.

  7. Supercritical fluid extraction and organic solvent microextraction of chemical agent simulants from soil

    SciTech Connect

    Griest, W.H.; Ramsey, R.S.; Ho, C.h.; Caldwell, W.M.

    1991-01-01

    Experiments with chemical warfare agent simulants suggest that supercritical fluid extraction can achieve good extraction recoveries of agents in soil and produce less laboratory waste than current organic solvent extraction methods. Two-ppm spikes in 1 g of Rocky Mountain Arsenal Standard Soil were extracted using 5% methanol in carbon dioxide at 300 atm for 2 min at 60{degrees}C. Recoveries (n=3) were 79{plus minus}23% for dimethylmethylphosphonate, 93{plus minus}14% for 2-chlorethylethylsulfide, 92{plus minus}13% for diisopropylfluorophosphate, and 95{plus minus}17% for diisopropylmethylphosphonate. A 5 min ultrasonic micro-scale extraction using methanol is more reproducible but less efficient.

  8. Fate and control of blistering chemical warfare agents in Kuwait`s desalination industry

    SciTech Connect

    Khordagui, H.K.

    1997-01-01

    Kuwait, as most of the other states located along the Western shores of the Arabian Gulf, relies upon the Gulf as its main drinking water resource via desalination. In case of seawater contamination with blistering chemical warfare agents, traces of the agents and/or degradation products in the finished water might pose a serious health hazard. The objective of the present review is to study the potential contamination, transport, fate, effect and control of blistering chemical warfare agents (CWAs), in the Kuwaiti desalination industry. In general, all the environmental factors involved in the aquatic degradation of CWAs in Kuwait marine environment except for the high salinity in case of blistering agents such as sulphur mustard, and in favor of a fast degradation process. In case of massive releases of CWAs near the Kuwaiti shorelines, turbulence resulting from tidal cycles and high temperature will affect the dissolution process and extend the toxicity of the insoluble agent. Post- and pre-chlorination during the course of seawater desalination will catalyze and significantly accelerate the hydrolysis processes of the CWAs. The heat exerted on CWAs during the power generation-desalination processes is not expected to thermally decompose them. However, the steam heat will augment the agent`s rate of hydrolysis with subsequent acceleration in their rate of detoxification. Conventional pretreatment of feed seawater for reverse-osmosis desalination is theoretically capable of reducing the concentration of CWAs by coprecipitation and adsorption on flocs formed during coagulation. Prechlorination and prolonged detention in time in pretreatment units will simultaneously promote hydrolysis reactions. 50 refs.

  9. Treatability study report for remediation of chemical warfare agent contaminated soils using peroxysulfate ex-situ treatment. Final report

    SciTech Connect

    Pugh, J.R.; Grinstead, J.H.; Farley, J.A.; Enlow, P.D.; Kelly, D.A.

    1996-07-01

    This laboratory scale study examines the feasibility of using peroxysulfate based oxidants to remediate soils contaminated with GB, Hi, and VX. The project was conducted with chemical warfare agent simulants. The study concludes that peroxysulfates, and particularly peroxydisulfate, can degrade chemical warfare agent simulants in soil and recommends continuing research.

  10. Development of land disposal restrictions for military chemical agent-associated waste

    SciTech Connect

    Kimmell, T.A.; Anderson, A.W.; Rosenblatt, D.H.

    1997-04-01

    In July 1988, the State of Utah, Department of Solid and Hazardous Waste (DSHW) listed certain military chemical agents as hazardous waste, as well as residues resulting from the demilitarization, treatment, and testing of these chemicals. These materials are listed as hazardous waste in Utah, but are not listed as hazardous wastes under the Federal Resource Conservation and Recovery Act (RCRA), the primary law governing management of hazardous waste in the United States. Pursuant to the 1984 Hazardous and Solid Waste Amendments (HSWA) to RCRA, the U.S. Environmental Protection Agency (EPA) has established Land Disposal Restriction (LDR) treatment standards for most categories of hazardous wastes. However, considering that EPA has not listed chemical agent-associated wastes as hazardous waste under RCRA, LDR treatment standards have not been established specifically for these wastes. In February 1995, the DSHW announced a regulatory initiative to develop LDRs for chemical agent-associated wastes and solicited data and information from the U.S. Army to support a rulemaking effort. The Army`s Chemical and Biological Defense Command (CBDCOM) was designated the lead agency for the Army to assist the DSHW in developing the rule. CBDCOM established the U.S. Army Land Disposal Restrictions Utah Group (LDRUG) and initiated a project with Argonne National Laboratory to support the LDRUG. The focus is on providing the state with accurate and up-to-date data and information to support the rulemaking and the establishment of LDRs. The purpose of this paper is to review the general direction of the proposed rule and to discuss overall progress. Potential impacts of the imposition of LDRs on the management of agent-associated wastes are also reviewed.

  11. Chemical agents for the control of plaque and plaque microflora: an overview.

    PubMed

    Gaffar, A; Afflitto, J; Nabi, N

    1997-10-01

    This presentation provides an overview of the technologies available for the chemical control of plaque. It is generally accepted that the formation of dental plaque at the interfaces of tooth/gingiva is one of the major causes of gingival inflammation and dental caries. Several therapeutic approaches have been used to control dental plaque and supragingival infections. These include fluoride preparations such as stannous fluoride, oxygenating agents, anti-attachment agents, and cationic and non-cationic antibacterial agents. Among the fluoride preparations, stable stannous fluoride pastes and gels have been shown to reduce supragingival plaque, gingivitis, hypersensitivity and caries. The effect of the oxygenating agents on the supragingival plaque has been equivocal, but recent data indicate that a stable agent which provides sustained active oxygen release is effective in controlling plaque. A polymer, PVPA, which reduced attachment of bacteria to teeth was shown to significantly reduce plaque formation in humans. A new generation of antibacterials includes non-ionics such as triclosan, which in combination with a special polymer delivery system, has been shown to reduce plaque, gingivitis, supragingival calculus and dental caries in long-term studies conducted around the world. Unlike the first generation of agents, the triclosan/copolymer/sodium fluoride system is effective in long-term clinicals and does not cause staining of teeth, increase in calculus, or disturbance in the oral microbial ecology. PMID:9395116

  12. Study of wavelength-shifting chemicals for use in large-scale water Cherenkov detectors

    SciTech Connect

    Sweany, M; Bernstein, A; Dazeley, S; Dunmore, J; Felde, J; Svoboda, R; Tripathi, S M

    2011-09-21

    Cherenkov detectors employ various methods to maximize light collection at the photomultiplier tubes (PMTs). These generally involve the use of highly reflective materials lining the interior of the detector, reflective materials around the PMTs, or wavelength-shifting sheets around the PMTs. Recently, the use of water-soluble wavelength-shifters has been explored to increase the measurable light yield of Cherenkov radiation in water. These wave-shifting chemicals are capable of absorbing light in the ultravoilet and re-emitting the light in a range detectable by PMTs. Using a 250 L water Cherenkov detector, we have characterized the increase in light yield from three compounds in water: 4-Methylumbelliferone, Carbostyril-124, and Amino-G Salt. We report the gain in PMT response at a concentration of 1 ppm as: 1.88 {+-} 0.02 for 4-Methylumbelliferone, stable to within 0.5% over 50 days, 1.37 {+-} 0.03 for Carbostyril-124, and 1.20 {+-} 0.02 for Amino-G Salt. The response of 4-Methylumbelliferone was modeled, resulting in a simulated gain within 9% of the experimental gain at 1 ppm concentration. Finally, we report an increase in neutron detection performance of a large-scale (3.5 kL) gadolinium-doped water Cherenkov detector at a 4-Methylumbelliferone concentration of 1 ppm.

  13. The comparison of removing plug by ultrasonic wave, chemical deplugging agent and ultrasound-chemical combination deplugging for near-well ultrasonic processing technology.

    PubMed

    Wang, Zhenjun; Xu, Yuanming; Bajracharya, Suman

    2015-11-01

    Near-well ultrasonic processing technology is characterized by high adaptability, simple operation, low cost and zero pollution. The main plugs of oil production include paraffin deposition plug, polymer plug, and drilling fluid plug etc. Although some good results have been obtained through laboratory experiments and field tests, systematic and intensive studies are absent for certain major aspects, such as: effects of ultrasonic treatment for different kinds of plugs and whether effect of ultrasound-chemicals combination deplugging is better than that of ultrasonic deplugging. In this paper, the experiments of removing drilling fluid plug, paraffin deposition plug and polymer plug by ultrasonic wave, chemical deplugging agent and ultrasound-chemical combination deplugging respectively are carried out. Results show that the effect of ultrasound-chemical combination deplugging is clearly better than that of using ultrasonic wave and chemical deplugging agent separately, which indicates that ultrasonic deplugging and chemical deplugging can produce synergetic effects. On the one hand, ultrasonic treatment can boost the activity of chemical deplugging agent and turn chemical deplugging into dynamic chemical process, promoting chemical agent reaction speed and enhancing deplugging effect; on the other hand, chemical agent can reduce the adhesion strength of plugs so that ultrasonic deplugging effect can be improved significantly. Experimental results provide important reference for near-well ultrasonic processing technology. PMID:26186853

  14. Validation of an evacuated canister method for measuring part-per-billion levels of chemical warfare agent simulants.

    PubMed

    Coffey, Christopher C; LeBouf, Ryan F; Calvert, Catherine A; Slaven, James E

    2011-08-01

    The National Institute for Occupational Safety and Health (NIOSH) research on direct-reading instruments (DRIs) needed an instantaneous sampling method to provide independent confirmation of the concentrations of chemical warfare agent (CWA) simulants. It was determined that evacuated canisters would be the method of choice. There is no method specifically validated for volatile organic compounds (VOCs) in the NIOSH Manual of Analytical Methods. The purpose of this study was to validate an evacuated canister method for sampling seven specific VOCs that can be used as a simulant for CWA agents (cyclohexane) or influence the DRI measurement of CWA agents (acetone, chloroform, methylene chloride, methyl ethyl ketone, hexane, and carbon tetrachloride [CCl4]). The method used 6-L evacuated stainless-steel fused silica-lined canisters to sample the atmosphere containing VOCs. The contents of the canisters were then introduced into an autosampler/preconcentrator using a microscale purge and trap (MPT) method. The MPT method trapped and concentrated the VOCs in the air sample and removed most of the carbon dioxide and water vapor. After preconcentration, the samples were analyzed using a gas chromatograph with a mass selective detector. The method was tested, evaluated, and validated using the NIOSH recommended guidelines. The evaluation consisted of determining the optimum concentration range for the method; the sample stability over 30 days; and the accuracy, precision, and bias of the method. This method meets the NIOSH guidelines for six of the seven compounds (excluding acetone) tested in the range of 2.3-50 parts per billion (ppb), making it suitable for sampling of these VOCs at the ppb level. PMID:21874953

  15. Impurity Profiling to Match a Nerve Agent to Its Precursor Source for Chemical Forensics Applications

    SciTech Connect

    Fraga, Carlos G.; Perez Acosta, Gabriel A.; Crenshaw, Michael D.; Wallace, Krys; Mong, Gary M.; Colburn, Heather A.

    2011-10-31

    Chemical forensics is an emerging field in homeland security that aims to attribute a weaponized toxic chemical or related material to its source. Herein, for the first time, trace impurities originating from a chemical precursor were used to match a synthesized nerve agent to its precursor source. Specifically, multiple batches of sarin and its intermediate were synthesized from two commercial stocks of methylphosphonic dichloride (DC) and were then matched by impurity profiling to their DC stocks from out of five possible stocks. This was possible because each DC stock had a unique impurity profile that, for the tested stocks, persisted through synthesis, decontamination, and sample preparation. This work may form a basis for using impurity profiling to help find and prosecute perpetrators of chemical attacks.

  16. Technology assessment for the determination of chemical agent vapors in demilitarization facilities: Final report

    SciTech Connect

    Maskarinec, M.P.; Wise, M.B.; Buchanan, M.V.

    1987-01-01

    A survey of analytical methods for the determination of chemical agents GB, VX, and HD was made. HD, or mustard, is bis-2-chloroethyl sulfide, and is classified as a blishtering agent. GB, or Sarin, is isopropyl methyl phosphonofluoridate. VX is O-ethyl-S-(2-diisopropylaminoethyl)methylphosphonothioate. Both GB and VX are nerve agents. Included were methods capable of providing for monitoring requirements at the time weighted average (TWA) and allowable stack concentration (ASC) levels in near real time. A review of the currently used automatic continuous air monitoring system (ACAMS) was made as well as a review of the recently developed atmospheric pressure ionization mass spectrometry (APIMS). This report recommends a strategy for research and development for near term and medium term improvement of the overall monitoring program. 12 refs., 1 tab.

  17. Experimental examination of ultraviolet Raman cross sections of chemical warfare agent simulants

    NASA Astrophysics Data System (ADS)

    Kullander, F.; Landström, L.; Lundén, H.; Wästerby, Pär.

    2015-05-01

    Laser induced Raman scattering from the commonly used chemical warfare agent simulants dimethyl sulfoxide, tributyl phosphate, triethyl phosphonoacetate was measured at excitation wavelengths ranging from 210 to 410 nm using a pulsed laser based spectrometer system with a probing distance of 1.4 m and with a field of view on the target of less than 1mm. For the purpose of comparison with well explored reference liquids the Raman scattering from simulants was measured in the form of an extended liquid surface layer on top of a silicon wafer. This way of measuring enabled direct comparison to the Raman scattering strength from cyclohexane. The reference Raman spectra were used to validate the signal strength of the simulants and the calibration of the experimental set up. Measured UV absorbance functions were used to calculate Raman cross sections. Established Raman cross sections of the simulants make it possible to use them as reference samples when measuring on chemical warfare agents in droplet form.

  18. Simulated experiment for elimination of air contaminated with odorous chemical agents by microwave plasma burner

    SciTech Connect

    Hong, Yong Cheol; Shin, Dong Hun; Uhm, Han Sup

    2007-10-15

    An experimental study on elimination of odorous chemical agent was carried out by making use of a microwave plasma burner, which consists of a microwave plasma torch and a reaction chamber with a fuel injector. Injection of hydrocarbon fuels into a high-temperature microwave torch plasma generates a plasma flame. The plasma flame can eliminate the odorous chemical agent diluted in air or purify the interior air of a large volume in isolated spaces. The specially designed reaction chamber eliminated H{sub 2}S and NH{sub 3} diluted in airflow rate of 5000 lpm (liters per minute), showing {beta} values of 46.52 and 39.69 J/l, respectively.

  19. III-nitride quantum cascade detector grown by metal organic chemical vapor deposition

    SciTech Connect

    Song, Yu Huang, Tzu-Yung; Badami, Pranav; Gmachl, Claire; Bhat, Rajaram; Zah, Chung-En

    2014-11-03

    Quantum cascade (QC) detectors in the GaN/Al{sub x}Ga{sub 1−x}N material system grown by metal organic chemical vapor deposition are designed, fabricated, and characterized. Only two material compositions, i.e., GaN as wells and Al{sub 0.5}Ga{sub 0.5}N as barriers are used in the active layers. The QC detectors operates around 4 μm, with a peak responsivity of up to ∼100 μA/W and a detectivity of up to 10{sup 8} Jones at the background limited infrared performance temperature around 140 K.

  20. Capillary - Discharge Based Hand-Held Detector For Chemical Vapor Monitoring

    DOEpatents

    Duan, Yixiang

    2005-05-31

    A handheld/portable detector for chemical vapor monitoring includes a housing and a discharge chamber that is established therein. The plasma discharge has a relatively small volume, e.g., in the micro-liter range. A first electrode and a second electrode are disposed within the discharge chamber and a discharge gap is established therebetween. A sample gas tube is in fluid communication with the discharge chamber and provides a sample gas to the discharge chamber. Also, a plasma gas tube is in fluid communication with the discharge chamber and provides a plasma gas thereto. Accordingly, the plasma gas can be used to maintain microplasma discharge between the electrodes and the sample gas can be introduced into the microplasma discharge. A spectrometer optically connected to the handheld/portable detector is used to measure the radiation emitted by the sample gas when subjected to the microplasma discharge.

  1. Survey: Destruction of chemical agent simulants in supercritical water oxidation. Master's thesis

    SciTech Connect

    Blank, M.R.

    1992-07-01

    The supercritical water oxidation (SCWO) process exhibits distinct advantages for destruction of toxic wastes. Examples of these wastes are two chemical agent simulants, dimethyl methylphosphonate (DMMP) and thiodiglycol (2,2'-thiodiethanol). DMMP is similar to the nerve agent GB Sarin in structure, and thiodiglycol is a hydrolysis product of the blister agent HD Sulfur Mustard. Both simulants are miscible in water and relatively non-toxic in comparison to the actual chemical agents. Using a Laboratory-scale, batch three temperatures were investigated: 425 deg C, 450 deg C, and 500 deg C with an initial concentration of one percent by volume, 11,450 mg/L for DMMP and 12,220 mg/L for thiodiglycol. Residence times investigated were: 1, 2, 3, 6, and 8 minutes. Reactor beat-up (H.U.) was determined to be one minute. Both pyrolysis and oxidation tests were conducted. Oxygen levels were uniformly set at 200% of stoichiometric requirements for the parent compounds.

  2. Tooth bleaching using three laser systems, halogen-light unit, and chemical action agents

    NASA Astrophysics Data System (ADS)

    Dostalova, Tatjana; Jelinkova, Helena; Housova, Devana; Sulc, Jan; Nemec, Michal; Koranda, Petr; Miyagi, Mitsunobu; Shi, Yi-Wei; Matsuura, Yuji

    2004-09-01

    μThe study describes the preclinical experience with laser-activated bleaching agent for discolored teeth. Extracted human upper central incisors were selected, and in the bleaching experiment 35% hydrogen peroxide was used. Three various laser systems and halogen-light unit for activation of the bleaching agent were applied. They were Alexandrite laser (wavelength 750 nm and 375 nm - SHG), Nd:YAG laser (wavelength 1.064 m), and Er:YAG laser (wavelength 2.94 μm). The halogen-light unit was used in a standard regime. The enamel surface was analyzed in the scanning electron microscope. The method of chemical oxidation results in a 2-3 shade change in one treatment. The halogen-light units produced the same effect with shorter time of bleaching process (from 630 s to 300 s). The Alexandrite laser (750 nm) and bleaching agent helped to reach the desired color shade after a shorter time (400 s). Alexandrite laser (375 nm) and Nd:YAG laser had no effect on the longevity of the process of bleaching. Overheating of the chemical bleaching agent was visible after Er:YAG laser activation (195 s). Slight surface modification after bleaching process was detected in SEM.

  3. Studies of the action of chemical agents on the heart. Annual report, February 1985-February 1986

    SciTech Connect

    Hassler, G.R.; Moutvic, R.R.

    1986-03-01

    This report describes initial studies to determine the subchronic effect of Soman and Sarin, on the electrical, mechanical, and neurochemical properties of the heart. Two different animal models are under development. The electrophysiologic and hemodynamic aspects of survival doses of chemical agent are begin studied in the dog. Two chronically instrumented dog models have been developed. The first is a hemodynamic dog model in which long-term measurements of left and right heart pressures, aortic flow, coronary flow as well as epicardial electrocardiograms, are monitored. The animals will be monitored at baseline and for one month following exposure in survival of a chemical-warfare-agent insult. These animals are stressed via treadmill exercise. The electrophysiology dog model consists of chronically implanted electrodes for performance of repetitive ventricular response stimulation, His bundle recording, and ECG analysis. Measurements are made prior to, and for one month following, exposure to survivable doses of CW agent. This dog model is further probed by sequential administration of various pharmacologic agents designed to study the autonomic status of the heart. All dogs and a limited number of the guinea pigs will be continuously monitored for occurrence of arrhythmic events utilizing Holter monitoring technology. The guinea pig neurochemical studies will include acetylcholines, choline acetyltransferase activity, QNB binding, choline uptake, norepinephrine levels and turnover, and norepinephrine uptake experiments.

  4. Characterization of chemical warfare G-agent hydrolysis products by surface-enhanced Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Inscore, Frank E.; Gift, Alan D.; Maksymiuk, Paul; Farquharson, Stuart

    2004-12-01

    The United States and its allies have been increasingly challenged by terrorism, and since the September 11, 2001 attacks and the war in Afghanistan and Iraq, homeland security has become a national priority. The simplicity in manufacturing chemical warfare agents, the relatively low cost, and previous deployment raises public concern that they may also be used by terrorists or rogue nations. We have been investigating the ability of surface-enhanced Raman spectroscopy (SERS) to detect extremely low concentrations (e.g. part-per-billion) of chemical agents, as might be found in poisoned water. Since trace quantities of nerve agents can be hydrolyzed in the presence of water, we have expanded our studies to include such degradation products. Our SERS-active medium consists of silver or gold nanoparticles incorporated into a sol-gel matrix, which is immobilized in a glass capillary. The choice of sol-gel precursor allows controlling hydrophobicity, while the porous silica network offers a unique environment for stabilizing the SERS-active metals. Here we present the use of these metal-doped sol-gels to selectively enhance the Raman signal of the hydrolyzed products of the G-series nerve agents.

  5. Reactive chromophores for sensitive and selective detection of chemical warfare agents

    NASA Astrophysics Data System (ADS)

    Frye-Mason, Greg; Leuschen, Martin; la Grone, Marcus; Wald, Lara; Aker, Craig; Dock, Matt; Hancock, Lawrence F.; Fagan, Steve; Paul, Kateri

    2004-08-01

    A new sensor for highly toxic species including chemical warfare (CW) agents has been developed. This sensor is based on a unique CW indicating chromophore (CWIC) developed by Professor Tim Swager at MIT. The CWIC was designed to be sensitive to the reactivity that makes these chemicals so toxic. Since it requires the reactivity of the agent to be detected, the CWIC technology has shown remarkable selectivity for nerve agent surrogates and some other highly toxic species, thereby demonstrating the potential to provide low false alarm rate detection. Since the chromophore has mini-mal fluorescence prior to reaction with an electrophilic and toxic chemical, the sensor acts in a dark field fluorescence mode. This provides the sensor with exceptional sensitivity and a potential to detect priority analytes well below levels detected by current hand held sensors. Finally, it is based on a simple optical detection scheme that enables small and rugged sensors to be developed and produced at a low enough cost so they can be widely utilized.

  6. Detection of simulants and degradation products of chemical warfare agents by vibrational spectroscopy

    NASA Astrophysics Data System (ADS)

    Ruiz-Pesante, Orlando; Pacheco-Londoño, Leonardo C.; Primera-Pedrozo, Oliva M.; Ortiz, William; Soto-Feliciano, Yadira M.; Nieves, Deborah E.; Ramirez, Michael L.; Hernández-Rivera, Samuel P.

    2007-04-01

    This work was focused in the measurement of spectroscopic signatures of Chemical Warfare Agent Simulants (CWAS) and degradation products of chemical agents using vibrational spectroscopy for the generation of spectroscopic libraries. The chemicals studied were: DMMP, DIMP, 2-CEES, 2-BAET, 1,4-thioxane, thiodiglycol sulfoxide, dihexylamine, cyclohexylamine, among others. Raman microscopy experiments were performed at different excitation wavelengths that spanned from NIR at 1064 and 785 nm to the VIS at 532, 514.5 and 488 nm and even the deep ultraviolet region at 244 nm. For the compounds studied the optimum excitation lines were 488 nm and 532 nm with a laser power of 25 mW. Among the most prominent bands were at these incident wavelengths were located ca. 652 and 1444 cm-1. Fourier Transform Infrared Spectroscopy in liquid and gas phase and Fiber Optics Coupled-Grazing Angle Probe-FTIR (FOCGAP- FTIR) were used to characterize the spectroscopic signature of target threat agents. The surface experiments were performed at detection levels of about 1 μg/cm2 suggest that limits of detection (LOD) achievable could be as low as nanograms/cm2. Remote sensing experiments were performed using a telescope coupled with a Raman spectrophotometer as a function of power and acquisition time. Characterization of compounds by vibrational spectroscopy and the early stages of the transition from the lab based experiments to remote detection experiments will be presented.

  7. Volatile anesthetics give a false-positive reading in chemical agent monitors in the "H" mode.

    PubMed

    Risk, D; Verpy, D; Conley, J D; Jacobson, T; Sawyer, T W

    2001-08-01

    Chemical agent monitors (CAMs) are routinely used by the armed forces and emergency response teams of many countries for the detection of the vesicant sulfur mustard (HD) and the G series of organophosphate nerve agents. Ambient operating room isoflurane levels were found to produce strong positive signals in the "H" mode when the CAM was used to monitor the efficacy of decontamination procedures during routine surgical procedures on HD-poisoned animals requiring up to 8 hours of general anesthesia. Subsequent testing showed that isoflurane, as well as desflurane, sevoflurane, halothane and methoxyflurane, produce two ionization peaks in the CAM response. One of these peaks is interpreted by the CAM processing software as HD, resulting in a CAM "H" mode bar response. No interference was encountered with isoflurane, desflurane, and sevoflurane when the CAM was set to the "G" mode, although extremely high (nonclinical) concentrations of halothane and methoxyflurane yielded a weakly positive bar response. These findings have potentially serious ramifications for the medical management of patients resulting from terrorist, military, or chemical agent decommissioning activity when concomitant chemical injuries are also possible. PMID:11515322

  8. Decontamination of chemical agents in Freon-113. Final report, February 1984-August 1988

    SciTech Connect

    Johnson, W.C.; Collins, K.R.; Ward, J.R.; Richmond, J.A.

    1993-06-01

    Freon solubilizes hydrophobic chemical warfare agents, such as soman, without damaging sensitive electronic equipment, such as night-vision goggles or communication equipment. Freon is used in this manner in the Nonaqueous Equipment Decontamination System (NAEDS) under development at CRDEC. The contaminated Freon is returned to a still, after which it is distilled through an aqueous layer containing bleach to decontaminate the residual agent. This report describes the results of experiments to measure how effectively agent is destroyed in the NAEDS. These results show that residual agent is still left in the redistilled Freon, and there is little difference whether the active decontaminant is removed from the aqueous layer. A mixture was prepared consisting of a 1:1:1 mixture of ethanol, 8 m sodium hydroxide, and Freon. It was demonstrated that the use of this mixture in the NAEDS would destroy all agent and that the redistilled Freon was free of soman. Freon-113, Bleach, Decontamination, Distillation, Non-Aqueous equipment decontamination system, Ethanol blend.

  9. Investigations into the chemical structure based selectivity of the microfabricated nitrogen-phosphorus detector

    SciTech Connect

    Brocato, Terisse A.; Hess, Ryan F.; Moorman, Matthew; Simonson, Robert J.

    2015-10-28

    The nitrogen and phosphorus atoms are constituents of some of the most toxic chemical vapors. Nitrogen-phosphorus gas chromatograph detectors (NPDs) rely on selective ionization of such compounds using ionization temperatures typically greater than 600 °C. NPDs have previously been reported to be 7*104× and 105× more sensitive for nitrogen and phosphorus, respectively, than for carbon. Presented here is an investigation of the structure-based selectivity of a microfabricated nitrogen-phosphorus detector (μNPD). The μNPD presented here is smaller than a dime and can be placed in a system that is 1/100th the size of a commercial NPD. Comparison of responses of such devices to homologous anilines (p-methoxyaniline, p-fluoroaniline, and aniline) revealed that detection selectivity, determined by the ratio of μNPD to nonselective flame ionization detector (FID) peak areas, is correlated with acid disassociation pKa values for the respective analine. Selectivity was determined to be greatest for p-methoxyaniline, followed by p-fluoroaniline, with aniline having the smallest response. The limit of detection for a nitrogen containing chemical, p-methoxyaniline, using the μNPD was determined to be 0.29 ng compared to 59 ng for a carbon chemical containing no nitrogen or phosphorus, 1,3,5-trimethybenzene. The μNPD presented here has increased detection for nitrogen and phosphorus compared to the FID and with a slight increase in detection of carbon compounds compared to commercial NPD's sensitivity to nitrogen and carbon.

  10. Investigations into the chemical structure based selectivity of the microfabricated nitrogen-phosphorus detector

    DOE PAGESBeta

    Brocato, Terisse A.; Hess, Ryan F.; Moorman, Matthew; Simonson, Robert J.

    2015-10-28

    The nitrogen and phosphorus atoms are constituents of some of the most toxic chemical vapors. Nitrogen-phosphorus gas chromatograph detectors (NPDs) rely on selective ionization of such compounds using ionization temperatures typically greater than 600 °C. NPDs have previously been reported to be 7*104× and 105× more sensitive for nitrogen and phosphorus, respectively, than for carbon. Presented here is an investigation of the structure-based selectivity of a microfabricated nitrogen-phosphorus detector (μNPD). The μNPD presented here is smaller than a dime and can be placed in a system that is 1/100th the size of a commercial NPD. Comparison of responses of suchmore » devices to homologous anilines (p-methoxyaniline, p-fluoroaniline, and aniline) revealed that detection selectivity, determined by the ratio of μNPD to nonselective flame ionization detector (FID) peak areas, is correlated with acid disassociation pKa values for the respective analine. Selectivity was determined to be greatest for p-methoxyaniline, followed by p-fluoroaniline, with aniline having the smallest response. The limit of detection for a nitrogen containing chemical, p-methoxyaniline, using the μNPD was determined to be 0.29 ng compared to 59 ng for a carbon chemical containing no nitrogen or phosphorus, 1,3,5-trimethybenzene. The μNPD presented here has increased detection for nitrogen and phosphorus compared to the FID and with a slight increase in detection of carbon compounds compared to commercial NPD's sensitivity to nitrogen and carbon.« less

  11. X-ray photoemission analysis of chemically modified TlBr surfaces for improved radiation detectors

    DOE PAGESBeta

    Nelson, A. J.; Voss, L. F.; Beck, P. R.; Graff, R. T.; Conway, A. M.; Nikolic, R. J.; Payne, S. A.; Lee, J. -S.; Kim, H.; Cirignano, L.; et al

    2013-01-12

    We subjected device-grade TlBr to various chemical treatments used in room temperature radiation detector fabrication to determine the resulting surface composition and electronic structure. As-polished TlBr was treated separately with HCl, SOCl2, Br:MeOH and HF solutions. High-resolution photoemission measurements on the valence band electronic structure and Tl 4f, Br 3d, Cl 2p and S 2p core lines were used to evaluate surface chemistry and shallow heterojunction formation. Surface chemistry and valence band electronic structure were correlated with the goal of optimizing the long-term stability and radiation response.

  12. Feasibility assessment of piezoelectric crystals as chemical warfare agent sensors. Final report, 1 August 1983-31 August 1985

    SciTech Connect

    Balog, P.P.; Stanford, T.B.; Nordstrom, R.J.; Burgener, R.C.

    1986-04-01

    The feasibility of a vibrating piezoelectric crystal as a CW agent detector was assessed by applying CW agent-sensitive coatings to the crystal and testing the detector with 0.3 mg/cum of GB (Sarin). Eight different coating materials were selected, based on previous data with G-agent simulants. No responses were observed to 0.3 mg/cum. GB, but three costings (XAD-4/Cu(2=)-diamine, polyethylenemaleate, and succinyl choline chloride) gave responses of -59 Hz, -22 Hz, and =11 Hz, respectively, to 10 mg/cm.of DIMP (diisopropyl methylphosphonate). Circuit optimization and the use of an operating frequency higher than 9 MHz is recommended to enhance sensitivity. Far-term recommendations are to apply the same coatings to a high-frequency (e.g., 300 MHz) surface acoustic-wave device and test again with CW agents.

  13. Evaluation of the vesicating properties of neutralized chemical agent identification sets. Final report, November 1995-August 1997

    SciTech Connect

    Olajos, E.J.; Salem, H.; Gieseking, J.K.

    1997-08-01

    Vesication and skin irritation studies were conducted in hairless guinea-pigs to determine the vesicant and skin irritation potential of Chemical Agent Identification Sets (CAIS). Guinea-pigs were topically dosed with `test article` NEAT HD, 10% agent/chloroform solutions, or product solutions (wastestreams) and evaluated for skin-damaging effects (gross and light microscopic). Product solutions from the chemical neutralization of neat sulfur mustard resulted in microvesicle formation (vesication). All agent-dosed (agent/chloroform solutions or HD) sites exhibited microblisters, as well as other histopathologic lesions of the skin. Wastestreams from the neutalization of agent (agent/chloroform; agent on charcoal) were devoid of microvesicant activity. Dermal irritant effects (erythema and edema) were consistent with the skin-injurious activity associated with the neutralizing reagent 1,3-dichloro-5,5-dimethylhydantoin (DCDMH).

  14. Next Generation Non-particulate Dry Nonwoven Pad for Chemical Warfare Agent Decontamination

    SciTech Connect

    Ramkumar, S S; Love, A; Sata, U R; Koester, C J; Smith, W J; Keating, G A; Hobbs, L; Cox, S B; Lagna, W M; Kendall, R J

    2008-05-01

    New, non-particulate decontamination materials promise to reduce both military and civilian casualties by enabling individuals to decontaminate themselves and their equipment within minutes of exposure to chemical warfare agents or other toxic materials. One of the most promising new materials has been developed using a needlepunching nonwoven process to construct a novel and non-particulate composite fabric of multiple layers, including an inner layer of activated carbon fabric, which is well-suited for the decontamination of both personnel and equipment. This paper describes the development of a composite nonwoven pad and compares efficacy test results for this pad with results from testing other decontamination systems. The efficacy of the dry nonwoven fabric pad was demonstrated specifically for decontamination of the chemical warfare blister agent bis(2-chloroethyl)sulfide (H or sulfur mustard). GC/MS results indicate that the composite fabric was capable of significantly reducing the vapor hazard from mustard liquid absorbed into the nonwoven dry fabric pad. The mustard adsorption efficiency of the nonwoven pad was significantly higher than particulate activated carbon (p=0.041) and was similar to the currently fielded US military M291 kit (p=0.952). The nonwoven pad has several advantages over other materials, especially its non-particulate, yet flexible, construction. This composite fabric was also shown to be chemically compatible with potential toxic and hazardous liquids, which span a range of hydrophilic and hydrophobic chemicals, including a concentrated acid, an organic solvent and a mild oxidant, bleach.

  15. Effects of chemical and biological warfare remediation agents on the materials of museum objects

    NASA Astrophysics Data System (ADS)

    Solazzo, C.; Erhardt, D.; Marte, F.; von Endt, D.; Tumosa, C.

    In the fall of 2001, anthrax-contaminated letters were sent to public figures in the United States. Chemical and radiation treatments were employed to decontaminate exposed buildings, objects, and materials. These treatments are effective, but potentially damaging to exposed objects and materials. The recommended surface chemical treatments include solutions, gels, and foams of oxidizing agents such as peroxides or chlorine bleaching agents. Such oxidizing agents are effective against a wide range of hazardous chemical and biological agents. Knowing how these reagents affect various substrates would help to anticipate and to minimize any potential damage. We are examining the effects on typical museum materials of reagents likely to be used, including hydrogen peroxide, sodium hypochlorite, and potassium peroxymonosulfate. Results so far show significant changes in a number of materials. Surface corrosion was observed on metals such as copper, silver, iron, and brass. Color changes occurred with at least one reagent in about one-fourth of the dyed fabric swatches tested, and about half of the inks. Samples of aged yellowed paper are bleached. Effects varied with both the substrate and the tested reagent. The observed changes were generally less drastic than might have been expected. Enough materials were affected, though, to preclude the use of these reagents on museum objects unless no less drastic alternative is available. It appears that many objects of lesser intrinsic value can be treated without severe loss of properties or usefulness. For example, most documents should remain legible if the appropriate reagent is used. This work will provide a basis for determining which treatment is most appropriate for a specific situation and what consequences are to be expected from other treatments.

  16. Disposal of chemical agents and munitions stored at Umatilla Depot Activity, Hermiston, Oregon

    SciTech Connect

    Zimmerman, G.P.; Hillsman, E.L.; Johnson, R.O.; Miller, R.L.; Patton, T.G.; Schoepfle, G.M.; Tolbert, V.R.; Feldman, D.L.; Hunsaker, D.B. Jr.; Kroodsma, R.L.; Morrissey, J.; Rickert, L.W.; Staub, W.P.; West, D.C.

    1993-02-01

    The Umatilla Depot Activity (UMDA) near Hermiston, Oregon, is one of eight US Army installations in the continental United States where lethal unitary chemical agents and munitions are stored, and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at UMDA consists of 11.6%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts), using a method based on five measures of risk for potential human health and ecosystem/environmental effects; the effectiveness and adequacy of emergency preparedness capabilities also played a key role in the FPEIS selection methodology. In some instances, the FPEIS included generic data and assumptions that were developed to allow a consistent comparison of potential impacts among programmatic alternatives and did not include detailed conditions at each of the eight installations. The purpose of this Phase 1 report is to examine the proposed implementation of on-site disposal at UMDA in light of more recent and more detailed data than those included in the FPEIS. Specifically, this Phase 1 report is intended to either confirm or reject the validity of on-site disposal for the UMDA stockpile. Using the same computation methods as in the FPEIS, new population data were used to compute potential fatalities from hypothetical disposal accidents. Results indicate that onsite disposal is clearly preferable to either continued storage at UMDA or transportation of the UMDA stockpile to another depot for disposal.

  17. Accelerating the degradation of green plant waste with chemical decomposition agents.

    PubMed

    Kejun, Sun; Juntao, Zhang; Ying, Chen; Zongwen, Liao; Lin, Ruan; Cong, Liu

    2011-10-01

    Degradation of green plant waste is often difficult, and excess maturity times are typically required. In this study, we used lignin, cellulose and hemicellulose assays; scanning electron microscopy; infrared spectrum analysis and X-ray diffraction analysis to investigate the effects of chemical decomposition agents on the lignocellulose content of green plant waste, its structure and major functional groups and the mechanism of accelerated degradation. Our results showed that adding chemical decomposition agents to Ficus microcarpa var. pusillifolia sawdust reduced the contents of lignin by 0.53%-11.48% and the contents of cellulose by 2.86%-7.71%, and increased the contents of hemicellulose by 2.92%-33.63% after 24 h. With increasing quantities of alkaline residue and sodium lignosulphonate, the lignin content decreased. Scanning electron microscopy showed that, after F. microcarpa var. pusillifolia sawdust was treated with chemical decomposition agents, lignocellulose tube wall thickness increased significantlyIncreases of 29.41%, 3.53% and 34.71% were observed after treatment with NaOH, alkaline residue and sodium lignosulphonate, respectively. Infrared spectroscopy showed that CO and aromatic skeleton stretching absorption peaks were weakened and the C-H vibrational absorption peak from out-of-plane in positions 2 and 6 (S units) (890-900 cm(-1)) was strengthened after F. microcarpa var. pusillifolia sawdust was treated with chemical decomposition agents, indicating a reduction in lignin content. Several absorption peaks [i.e., C-H deformations (asymmetry in methyl groups, -CH(3)- and -CH(2)-) (1450-1460 cm(-1)); Aliphatic C-H stretching in methyl and phenol OH (1370-1380 cm(-1)); CO stretching (cellulose and hemicellulose) (1040-1060 cm(-1))] that indicate the presence of a chemical bond between lignin and cellulose was reduced, indicating that the chemical bond between lignin and cellulose had been partially broken. X-ray diffraction analysis showed that Na

  18. Combined effect of microbial and chemical control agents on subterranean termites.

    PubMed

    Wright, Maureen S; Lax, Alan R

    2013-10-01

    Termite mortality was measured when fungi were combined with bacteria or a chemical termiticide to determine whether a synergistic effect occurred. The fungus Beauveria bassiana was combined with the non-repellant chemical termiticide imidacloprid. Of the three B. bassiana strains tested one, B. bassiana ATCC 90519, was sufficiently pathogenic on its own that the advantage of a supplementary chemical treatment was marginal. The mortality caused by another fungal strain, B. bassiana ATCC 26037, was improved in combination with imidacloprid at both of the tested chemical concentrations over the first 14 days. The remaining fungal strain, B. bassiana ATCC 90518, demonstrated an overall mortality rate in combination with imidacloprid of 82.5%, versus a rate of 65.0% for the fungus alone. The fungus Isaria fumosorosea (Ifr) was combined with the bacterium Bacillus thuringiensis (Bt). On day 5, Ifr, Bt, and the combined treatment at a 10(6) spores or cells/ml dosage caused 8.8%, 22.5%, and 15.0% mortality, respectively. The Bt and combined mortality rates are not significantly different. Control mortality on day 5 was 5.0%. On day 13 the combined 10(6) treatment mortality rate was 91.3%, which was significantly higher than all other treatments: control at 17.5%, Ifr at 36.3% and Bt at 35.0%. When Ifr and Bt were applied at a 10(9) spores or cells/ml dosage, Ifr alone caused a mortality rate of 97.5% as early as day 5. The combination with Bt could not significantly increase the effectiveness of this dosage. These data demonstrate the potential for synergistic effects of fungal and chemical treatment methods, thereby broadening the use of microbial control agents and reducing the quantity of chemical agents necessary to effect control. PMID:24037651

  19. Chemical feed control using coagulation computer models and a streaming current detector.

    PubMed

    Yavich, Alex A; Van De Wege, Jim

    2013-01-01

    This paper describes the use of both the streaming current detector (SCD) and coagulation computer models to provide real-time data for required coagulant feed rates. The method for computer modeling of coagulation and other water treatment processes/operations was originally developed for Lake Michigan Filtration Plant in Grand Rapids, Michigan (MI). Since the initial implementation, a number of water treatment plants (WTPs) in the United States have begun routinely utilizing computer models for chemical feed control and process performance optimization. One plant, Holland WTP in Holland, MI, currently employs both an SCD and a coagulation computer model for chemical feed control. Case studies presented in this paper compare the performance of coagulation computer models and the SCD in full-scale operation. PMID:23787322

  20. Limitations and challenges in treatment of acute chemical warfare agent poisoning.

    PubMed

    Thiermann, Horst; Worek, Franz; Kehe, Kai

    2013-12-01

    Recent news from Syria on a possible use of chemical warfare agents made the headlines. Furthermore, the motivation of terrorists to cause maximal harm shifts these agents into the public focus. For incidents with mass casualties appropriate medical countermeasures must be available. At present, the most important threats arise from nerve agents and sulfur mustard. At first, self-protection and protection of medical units from contamination is of utmost importance. Volatile nerve agent exposure, e.g. sarin, results in fast development of cholinergic crisis. Immediate clinical diagnosis can be confirmed on-site by assessment of acetylcholinesterase activity. Treatment with autoinjectors that are filled with 2mg atropine and an oxime (at present obidoxime, pralidoxime, TMB-4 or HI-6) are not effective against all nerve agents. A more aggressive atropinisation has to be considered and more effective oximes (if possible with a broad spectrum or a combination of different oximes) as well as alternative strategies to cope with high acetylcholine levels at synaptic sites should be developed. A further gap exists for the treatment of patients with sustained cholinergic crisis that has to be expected after exposure to persistent nerve agents, e.g. VX. The requirement for long-lasting artificial ventilation can be reduced with an oxime therapy that is optimized by using the cholinesterase status for guidance or by measures (e.g. scavengers) that are able to reduce the poison load substantially in the patients. For sulfur mustard poisoning no specific antidote is available until now. Symptomatic measures as used for treatment of burns are recommended together with surgical or laser debridement. Thus, huge amounts of resources are expected to be consumed as wound healing is impaired. Possible depots of sulfur mustard in tissues may aggravate the situation. More basic knowledge is necessary to improve substantially therapeutic options. The use of stem cells may provide a new

  1. Efficacy of liquid and foam decontamination technologies for chemical warfare agents on indoor surfaces.

    PubMed

    Love, Adam H; Bailey, Christopher G; Hanna, M Leslie; Hok, Saphon; Vu, Alex K; Reutter, Dennis J; Raber, Ellen

    2011-11-30

    Bench-scale testing was used to evaluate the efficacy of four decontamination formulations on typical indoor surfaces following exposure to the liquid chemical warfare agents sarin (GB), soman (GD), sulfur mustard (HD), and VX. Residual surface contamination on coupons was periodically measured for up to 24h after applying one of four selected decontamination technologies [0.5% bleach solution with trisodium phosphate, Allen Vanguard Surface Decontamination Foam (SDF™), U.S. military Decon Green™, and Modec Inc. and EnviroFoam Technologies Sandia Decontamination Foam (DF-200)]. All decontamination technologies tested, except for the bleach solution, performed well on nonporous and nonpermeable glass and stainless-steel surfaces. However, chemical agent residual contamination typically remained on porous and permeable surfaces, especially for the more persistent agents, HD and VX. Solvent-based Decon Green™ performed better than aqueous-based bleach or foams on polymeric surfaces, possibly because the solvent is able to penetrate the polymer matrix. Bleach and foams out-performed Decon Green for penetrating the highly polar concrete surface. Results suggest that the different characteristics needed for an ideal and universal decontamination technology may be incompatible in a single formulation and a strategy for decontaminating a complex facility will require a range of technologies. PMID:21944706

  2. Technical support for recovery phase decision-making in the event of a chemical warfare agent release

    SciTech Connect

    Watson, A.; Shugart, L.; Buchanan, M.; Jenkins, R.; Kistner, S.; Halbrook, R.

    1995-12-31

    Persistent chemical warfare agents such as the nerve agent VX and sulfur mustard were originally designed as terrain denial materials on the chemical battlefield. As a consequence, they do not rapidly degrade. In the course of preparedness planning for disposal of the US unitary stockpile of chemical warfare agents, communities have raised the issue of determining environmental concentrations and the potential health consequences of persistent agents following any agent event. This issue is common to several chemical warfare munition and materiel disposal activities in the United States, as well as for developing verification and compliance monitoring programs integral to the international Chemical Weapons Convention. Experimental research supporting the development of environmental monitoring protocols are summarized. They include the development of blood cholinesterase activity as a biomonitor of nerve agent exposure in domestic beef and dairy cattle, horses and sheep; measuring the permeation rates of construction materials such as unpainted wood and gypsum wall board to agent simulants; and developing an experimental monitoring protocol for agents in meat and grain.

  3. Thermal and fast neutron detection in chemical vapor deposition single-crystal diamond detectors

    NASA Astrophysics Data System (ADS)

    Almaviva, S.; Marinelli, M.; Milani, E.; Prestopino, G.; Tucciarone, A.; Verona, C.; Verona-Rinati, G.; Angelone, M.; Lattanzi, D.; Pillon, M.; Montereali, R. M.; Vincenti, M. A.

    2008-03-01

    Recently, a compact solid-state neutron detector capable of simultaneously detecting thermal and fast neutrons was proposed [M. Marinelli et al., Appl. Phys. Lett. 89, 143509 (2006)]. Its design is based on a p-type/intrinsic/metal layered structure obtained by Microwave Plasma Chemical Vapor Deposition (CVD) of homoepitaxial diamond followed by thermal evaporation of an Al contact and a L6iF converting layer. Fast neutrons are directly detected in the CVD diamond bulk, since they have enough energy to produce the C12(n,α)B9e reaction in diamond. Thermal neutrons are instead converted into charged particles in the L6iF layer through the L6i(n ,α)T nuclear reaction. These charged particles are then detected in the diamond layer. The thickness of the L6iF converting layer and the CVD diamond sensing layer affect the counting efficiency and energy resolution of the detector both for low- (thermal) and high-energy neutrons. An analysis is carried out on the dynamics of the L6i(n ,α)T and the C12(n,α)B9e reactions products, and the distribution of the energy released inside the sensitive layer is calculated. The detector counting efficiency and energy resolution were accordingly derived as a function of the thickness of the L6iF and CVD diamond layers, both for thermal and fast neutrons, thus allowing us to choose the optimum detector design for any particular application. Comparison with experimental results is also reported.

  4. Ability of fourteen chemical agents used in dental practice to induce chromosome aberrations in Syrian hamster embryo cells.

    PubMed

    Hikiba, Hirohito; Watanabe, Eiko; Barrett, J Carl; Tsutsui, Takeki

    2005-01-01

    To assess the genotoxicity of 14 chemical agents used in dental practice, the ability of these agents to induce chromosome aberrations was examined using Syrian hamster embryo (SHE) cells. Statistically significant increases in the frequencies of chromosome aberrations were induced in SHE cells treated with 7 of 10 chemical agents used as endodontic medicaments, that is, carbol camphor, m-cresol, eugenol, guaiacol, zinc oxide, hydrogen peroxide, and formaldehyde. The other 3 chemical agents, that is, thymol, glutaraldehyde, and iodoform, did not increase the levels of chromosome aberrations. Of the 4 chemical agents that are used as an antiseptic on the oral mucosa, chromosome aberrations were induced by iodine, but not by the other 3 antiseptics, benzalkonium chloride, benzethonium chloride, and chlorhexidine. Among the 6 chemical agents exhibiting a negative response in the assay, only thymol induced chromosome aberrations in the presence of exogenous metabolic activation. Our results indicate that chemical agents having a positive response in the present study are potentially genotoxic to mammalian cells and need to be studied further in detail. PMID:15665446

  5. High-throughput screening of chemical exchange saturation transfer MR contrast agents.

    PubMed

    Liu, Guanshu; Gilad, Assaf A; Bulte, Jeff W M; van Zijl, Peter C M; McMahon, Michael T

    2010-01-01

    A new high-throughput MRI method for screening chemical exchange saturation transfer (CEST) agents is demonstrated, allowing simultaneous testing of multiple samples with minimal attention to sample configuration and shimming of the main magnetic field (B(0)). This approach, which is applicable to diamagnetic, paramagnetic and liposome CEST agents, employs a set of inexpensive glass or plastic capillary tubes containing CEST agents put together in a cheap plastic tube holder, without the need for liquid between the tubes to reduce magnetic susceptibility effects. In this setup, a reference image of direct water saturation spectra is acquired in order to map the absolute water frequency for each volume element (voxel) in the sample image, followed by an image of saturation transfer spectra to determine the CEST properties. Even though the field over the total sample is very inhomogeneous due to air-tube interfaces, the shape of the direct saturation spectra is not affected, allowing removal of susceptibility shift effects from the CEST data by using the absolute water frequencies from the reference map. As a result, quantitative information such as the mean CEST intensity for each sample can be extracted for multiple CEST agents at once. As an initial application, we demonstrate rapid screening of a library of 16 polypeptides for their CEST properties, but in principle the number of tubes is limited only by the available signal-noise-ratio, field of view and gradient strength for imaging. PMID:20586030

  6. Screening of alternative technologies to incineration for treatment of chemical-agent-contaminated soil

    SciTech Connect

    Shem, L.M.; Ballou, S.W.; Besmer, M.G.

    1996-12-31

    As part of the Rocky Mountain Arsenal (RMA) Remedial Investigation/Feasibility Study, RMA has contracted Argonne National Laboratory to investigate potential remedial alternatives for the cleanup of agent-contaminated soils. The chemical agents of concern include levinstein mustard, lewisite, sarin, and VX. This investigation has been initially divided into three phases: (1) a literature search to determine what, if any, previous studies have been conducted; (2) a technologies-screening critique of remedial technologies as alternatives to incineration; and (3) an investigation of promising alternatives on RMA soil at the laboratory and bench-scale levels. This paper summarizes the document produced as a result of the technologies screening. The purpose of the document was to determine the applicability of 25 technologies to remediation of agent-contaminated soil for a general site. Technologies were critiqued on the basis of applicability to soil type, applicability to the agents of concern at RMA, applicability to other types of contaminants, cost of the treatment, current status of the technology, and residuals produced.

  7. CHEMICAL SHORELINE CLEANING AGENTS FOR OIL SPILLS - UPDATE STATE-OF-THE-ART ON MECHANISMS OF ACTION AND FACTORS INFLUENCING PERFORMANCE

    EPA Science Inventory

    This report presents information on (1) brief consideration of common cleaning strategies for stranded oil on shorelines, (2) the mechanism of action of chemical shoreline cleaning agents, (3) factors affecting performance and its measurement for chemical cleaning agents, (4) lab...

  8. Fragmentation of molecular ions in differential mobility spectrometry as a method for identification of chemical warfare agents.

    PubMed

    Maziejuk, M; Puton, J; Szyposzyńska, M; Witkiewicz, Z

    2015-11-01

    The subject of the work is the use of differential mobility spectrometry (DMS) for the detection of chemical warfare agents (CWA). Studies were performed for mustard gas, i.e., bis(2-chloroethyl)sulfide (HD), sarin, i.e., O-isopropyl methylphosphonofluoridate (GB) and methyl salicylate (MS) used as test compounds. Measurements were conducted with two ceramic DMS analyzers of different constructions allowing the generation of an electric field with an intensity of more than 120 Td. Detector signals were measured for positive and negative modes of operation in a temperature range from 0 to 80 °C. Fragmentations of ions containing analyte molecules were observed for all tested compounds. The effective temperatures of fragmentation estimated on the basis of dispersion plots were equal from about 148 °C for GB to 178 °C for MS. It was found that values of separation voltage (SV) and compensation voltage (CV) at which the fragmentation of sample ions is observed may be the parameters improving the certainty of detection for different analytes. The DMS analyzers enabling the observation of ion fragmentation can be successfully used for effective CWA detection. PMID:26452948

  9. Organic Chemical Attribution Signatures for the Sourcing of a Mustard Agent and Its Starting Materials.

    PubMed

    Fraga, Carlos G; Bronk, Krys; Dockendorff, Brian P; Heredia-Langner, Alejandro

    2016-05-17

    Chemical attribution signatures (CAS) are being investigated for the sourcing of chemical warfare (CW) agents and their starting materials that may be implicated in chemical attacks or CW proliferation. The work reported here demonstrates for the first time trace impurities from the synthesis of tris(2-chloroethyl)amine (HN3) that point to the reagent and the specific reagent stocks used in the synthesis of this CW agent. Thirty batches of HN3 were synthesized using different combinations of commercial stocks of triethanolamine (TEA), thionyl chloride, chloroform, and acetone. The HN3 batches and reagent stocks were then analyzed for impurities by gas chromatography/mass spectrometry. All the reagent stocks had impurity profiles that differentiated them from one another. This was demonstrated by building classification models with partial least-squares discriminant analysis (PLSDA) and obtaining average stock classification errors of 2.4, 2.8, 2.8, and 11% by cross-validation for chloroform (7 stocks), thionyl chloride (3 stocks), acetone (7 stocks), and TEA (3 stocks), respectively, and 0% for a validation set of chloroform samples. In addition, some reagent impurities indicative of reagent type were found in the HN3 batches that were originally present in the reagent stocks and presumably not altered during synthesis. More intriguing, impurities in HN3 batches that were apparently produced by side reactions of impurities unique to specific TEA and chloroform stocks, and thus indicative of their use, were observed. PMID:27116337

  10. Evaluation of risk assessment guideline levels for the chemical warfare agents mustard, GB, and VX.

    SciTech Connect

    Hartmann, H.; Environmental Assessment

    2002-06-01

    The U.S. Army has estimated acute lethality guideline levels for inhalation of the chemical warfare agents mustard, GB, and VX. These levels are expressed as dosages measured in milligram-minutes per cubic meter (mg-min/m3). The National Advisory Council has also proposed acute emergency guideline levels (AEGLs) for the agents. The AEGLs are threshold exposure limits for the general public for mild effects, serious adverse effects, and lethality. They are expressed as air concentrations (in units of mg/m3) and are applicable to emergency exposure periods ranging from 10 min to 8 h. The report discusses strengths and deficiencies in the levels, important parameters (i.e., exposure time, breathing rate) that need to be explicitly addressed in deriving the guideline levels, and possible impacts that could result from using AEGLs instead of guideline dosages in future assessments.

  11. DNA-damaging agents in cancer chemotherapy: serendipity and chemical biology.

    PubMed

    Cheung-Ong, Kahlin; Giaever, Guri; Nislow, Corey

    2013-05-23

    DNA-damaging agents have a long history of use in cancer chemotherapy. The full extent of their cellular mechanisms, which is essential to balance efficacy and toxicity, is often unclear. In addition, the use of many anticancer drugs is limited by dose-limiting toxicities as well as the development of drug resistance. Novel anticancer compounds are continually being developed in the hopes of addressing these limitations; however, it is essential to be able to evaluate these compounds for their mechanisms of action. This review covers the current DNA-damaging agents used in the clinic, discusses their limitations, and describes the use of chemical genomics to uncover new information about the DNA damage response network and to evaluate novel DNA-damaging compounds. PMID:23706631

  12. Single-particle aerosol mass spectrometry for the detection and identification of chemical warfare agent simulants.

    PubMed

    Martin, Audrey N; Farquar, George R; Frank, Matthias; Gard, Eric E; Fergenson, David P

    2007-08-15

    Single-particle aerosol mass spectrometry (SPAMS) was used for the real-time detection of liquid nerve agent simulants. A total of 1000 dual-polarity time-of-flight mass spectra were obtained for micrometer-sized single particles each of dimethyl methyl phosphonate, diethyl ethyl phosphonate, diethyl phosphoramidate, and diethyl phthalate using laser fluences between 0.58 and 7.83 nJ/microm2, and mass spectral variation with laser fluence was studied. The mass spectra obtained allowed identification of single particles of the chemical warfare agent (CWA) simulants at each laser fluence used although lower laser fluences allowed more facile identification. SPAMS is presented as a promising real-time detection system for the presence of CWAs. PMID:17630721

  13. Setting up a mobile Lidar (DIAL) system for detecting chemical warfare agents

    NASA Astrophysics Data System (ADS)

    Kavosh Tehrani, M.; Mohammad, M. Malek; Jaafari, E.; Mobashery, A.

    2015-03-01

    The mobile light detection and ranging DIAL system of Malek Ashtar University of Technology has been developed for the detection of chemical warfare agents whose absorption wavelengths are in the range of 9.2-10.8 μm tunable CO2 lasers of the system. In this paper, this system is first described and then ammonia detection is analyzed experimentally. Also, experimental results of detecting a sarin agent simulant, dimethyl-methyl phosphonate (DMMP), are presented. The power levels received from different ranges to detect specific concentrations of NH3 and DMMP have been measured and debated. The primary test results with a 150 ns clipped pulse width by passive pinhole plasma shutter indicate that the system is capable of monitoring several species of pollutants in the range of about 1 km, with a 20 m spatial and 2 min temporal resolution.

  14. Decontamination of adsorbed chemical warfare agents on activated carbon using hydrogen peroxide solutions.

    PubMed

    Osovsky, Ruth; Kaplan, Doron; Nir, Ido; Rotter, Hadar; Elisha, Shmuel; Columbus, Ishay

    2014-09-16

    Mild treatment with hydrogen peroxide solutions (3-30%) efficiently decomposes adsorbed chemical warfare agents (CWAs) on microporous activated carbons used in protective garments and air filters. Better than 95% decomposition of adsorbed sulfur mustard (HD), sarin, and VX was achieved at ambient temperatures within 1-24 h, depending on the H2O2 concentration. HD was oxidized to the nontoxic HD-sulfoxide. The nerve agents were perhydrolyzed to the respective nontoxic methylphosphonic acids. The relative rapidity of the oxidation and perhydrolysis under these conditions is attributed to the microenvironment of the micropores. Apparently, the reactions are favored due to basic sites on the carbon surface. Our findings suggest a potential environmentally friendly route for decontamination of adsorbed CWAs, using H2O2 without the need of cosolvents or activators. PMID:25133545

  15. Studies on the chemical synthesis and characterization of lead oxide nanoparticles with different organic capping agents

    SciTech Connect

    Arulmozhi, K. T.; Mythili, N.

    2013-12-15

    Lead oxide (PbO) nanoparticles were chemically synthesized using Lead (II) acetate as precursor. The effects of organic capping agents such as Oleic acid, Ethylene Diamine Tetra Acetic acid (EDTA) and Cetryl Tri Methyl Butoxide (CTAB) on the size and morphology of the nanoparticles were studied. Characterization techniques such as X-ray diffraction (XRD), Fourier Transform-Infrared spectroscopy (FT-IR), Photoluminescence (PL) Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive Spectroscopy (EDS) and Transmission Electron Microscopy (TEM) were used to analyse the prepared nanoparticles for their physical, structural and optical properties. The characterization studies reveal that the synthesized PbO nanoparticles had well defined crystalline structure and sizes in the range of 25 nm to 36 nm for capping agents used and 40 nm for pure PbO nanoparticles.

  16. Impurity profiling to match a nerve agent to its precursor source for chemical forensics applications.

    PubMed

    Fraga, Carlos G; Acosta, Gabriel A Pérez; Crenshaw, Michael D; Wallace, Krys; Mong, Gary M; Colburn, Heather A

    2011-12-15

    Chemical forensics is a developing field that aims to attribute a chemical (or mixture) of interest to its source by the analysis of the chemical itself or associated material constituents. Herein, for the first time, trace impurities detected by gas chromatography/mass spectrometry and originating from a chemical precursor were used to match a synthesized nerve agent to its precursor source. Specifically, six batches of sarin (GB, isopropyl methylphosphonofluoridate) and its intermediate methylphosphonic difluoride (DF) were synthesized from two commercial stocks of 97% pure methylphosphonic dichloride (DC); the GB and DF were then matched by impurity profiling to their DC stocks from a collection of five possible stocks. Source matching was objectively demonstrated through the grouping by hierarchal cluster analysis of the GB and DF synthetic batches with their respective DC precursor stocks based solely upon the impurities previously detected in five DC stocks. This was possible because each tested DC stock had a unique impurity profile that had 57% to 88% of its impurities persisting through product synthesis, decontamination, and sample preparation. This work forms a basis for the use of impurity profiling to help find and prosecute perpetrators of chemical attacks. PMID:22040126

  17. Surface-immobilization of molecules for detection of chemical warfare agents.

    PubMed

    Bhowmick, Indrani; Neelam

    2014-09-01

    Fabrication of nanoscale molecular assemblies with advanced functionalities is an emerging field. These systems provide new perspectives for the detection and degradation of chemical warfare agents (CWAs). The main concern in this context is the design and fabrication of "smart surfaces" able to immobilize functional molecules which can perform a certain function or under the input of external stimuli. This review addresses the above points dealing with immobilization of various molecules on different substrates and describes their adequacy as sensors for the detection of CWAs. PMID:24998209

  18. LANL organic analysis detection capabilities for chemical and biological warfare agents

    SciTech Connect

    Ansell, G.B.; Cournoyer, M.E.; Hollis, K.W.; Monagle, M.

    1996-12-31

    Organic analysis is the analytical arm for several Los Alamos National Laboratory (LANL) research programs and nuclear materials processes, including characterization and certification of nuclear and nonnuclear materials used in weapons, radioactive waste treatment and waste certification programs. Organic Analysis has an extensive repertoire of analytical technique within the group including headspace gas, PCBs/pesticides, volatile organics and semivolatile organic analysis. In addition organic analysis has mobile labs with analytic capabilities that include volatile organics, total petroleum hydrocarbon, PCBs, pesticides, polyaromatic hydrocarbons and high explosive screening. A natural extension of these capabilities can be applied to the detection of chemical and biological agents,

  19. 3-Hydrazinoindolin-2-one derivatives: Chemical classification and investigation of their targets as anticancer agents.

    PubMed

    Ibrahim, Hany S; Abou-Seri, Sahar M; Abdel-Aziz, Hatem A

    2016-10-21

    Isatin is a well acknowledged pharmacophore in many clinically approved drugs used for treatment of cancer. 3-Hydrazinoindolin-2-one, as a derivative of isatin, represents a pharmacophore of an important class of biologically active pharmaceutical agents by virtue of their diverse biological activities. In this review, anticancer activity will be on focus for compounds derived from 3-hydrazinoindolin-2-one. They are classified according to their chemical structure into nine different classes. In each class, different compounds were browsed, showing their anticancer activity and their potential targets. Moreover, crystallographic data or docking studies were highlighted for some compounds, when available, to provide a deep understanding of their mechanisms of action. PMID:27391135

  20. Supramolecular chemistry and chemical warfare agents: from fundamentals of recognition to catalysis and sensing.

    PubMed

    Sambrook, M R; Notman, S

    2013-12-21

    Supramolecular chemistry presents many possible avenues for the mitigation of the effects of chemical warfare agents (CWAs), including sensing, catalysis and sequestration. To-date, efforts in this field both to study fundamental interactions between CWAs and to design and exploit host systems remain sporadic. In this tutorial review the non-covalent recognition of CWAs is considered from first principles, including taking inspiration from enzymatic systems, and gaps in fundamental knowledge are indicated. Examples of synthetic systems developed for the recognition of CWAs are discussed with a focus on the supramolecular complexation behaviour and non-covalent approaches rather than on the proposed applications. PMID:24048279

  1. Niobium(V) saponite clay for the catalytic oxidative abatement of chemical warfare agents.

    PubMed

    Carniato, Fabio; Bisio, Chiara; Psaro, Rinaldo; Marchese, Leonardo; Guidotti, Matteo

    2014-09-15

    A Nb(V)-containing saponite clay was designed to selectively transform toxic organosulfur chemical warfare agents (CWAs) under extremely mild conditions into nontoxic products with reduced environmental impact. Thanks to the insertion of Nb(V) sites within the saponite framework, a bifunctional catalyst with strong oxidizing and acid properties was obtained. Remarkable activity and high selectivity were observed for the oxidative abatement of (2-chloroethyl)ethyl sulfide (CEES), a simulant of sulfur mustard, at room temperature with aqueous hydrogen peroxide. This performance was significantly better compared to a conventional commercial decontamination powder. PMID:25056451

  2. Lymphohematopoietic Cancers Induced by Chemicals and Other Agents: Overview and Implications for Risk Assessment (External Review Draft)

    EPA Science Inventory

    This draft report provides an overview of the types of mechanisms underlying the lymphohematopoietic cancers induced by chemical agents and radiation in humans, with a primary emphasis on leukemia and leukemia-inducing agents. It focuses on how mechanistic information on human l...

  3. Scanning surface-enhanced Raman spectroscopy (SERS) of chemical agent simulants on templated Au-Ag nanowire substrates

    NASA Astrophysics Data System (ADS)

    Hoffmann, J. A.; Miragliotta, J. A.; Wang, J.; Tyagi, P.; Maddanimath, T.; Gracias, D. H.; Papadakis, S. J.

    2009-05-01

    We report the results of scanning micro-Raman spectroscopy obtained on Au-Ag nanowires for a variety of chemical warfare agent simulants. Rough silver segments embedded in gold nanowires showed enhancement of 105 - 107 and allowed unique identification of 3 of 4 chemical agent simulants tested. These results suggest a promising method for detection of compounds significant for security applications, leading to sensors that are compact and selective.

  4. A Survey of Commercially Available Chemical Agent Instrumentation for Use in the Field

    SciTech Connect

    Haas, J S; Alcaraz, A; Andresen, B D; Pruneda, C O

    2002-03-01

    Lawrence Livermore National Laboratory's (LLNL) Forensic Science Center (FSC) has extensive experience and capabilities in the analysis of chemical agents (CA) and related compounds as well as experience in identifying these materials in the field (i.e. samples such as those found in soils, liquids, gases). An open source survey was performed to determine viable, commercially available technology that can detect, in situ, CA and also meet field-use performance criteria as specified by the Program Management Consultant (PMC). The performance requirements of the technology include accuracy, reliability, integration onto robotics, and chemical detection sensitivities that meet required specifications. Not included in this survey are technologies and methodologies to detect CA decomposition products and related waste streams.

  5. Remote Continuous Wave and Pulsed Laser Raman Detection of Chemical Warfare Agents Simulants and Toxic Industrial Compounds

    NASA Astrophysics Data System (ADS)

    Ortiz-Rivera, William; Pacheco-Londoño, Leonardo C.; Hernández-Rivera, Samuel P.

    2010-09-01

    This study describes the design, assembly, testing and comparison of two Remote Raman Spectroscopy (RRS) systems intended for standoff detection of hazardous chemical liquids. Raman spectra of Chemical Warfare Agents Simulants (CWAS) and Toxic Industrial Compounds (TIC) were measured in the laboratory at a 6.6 m source-target distance using continuous wave (CW) laser detection. Standoff distances for pulsed measurements were 35 m for dimethyl methylphosphonate (DMMP) detection and 60, 90 and 140 m for cyclohexane detection. The prototype systems consisted of a Raman spectrometer equipped with a CCD detector (for CW measurements) and an I-CCD camera with time-gated electronics (for pulsed laser measurements), a reflecting telescope, a fiber optic assembly, a single-line CW laser source (514.5, 488.0, 351.1 and 363.8 nm) and a frequency-doubled single frequency Nd:YAG 532 nm laser (5 ns pulses at 10 Hz). The telescope was coupled to the spectrograph using an optical fiber, and filters were used to reject laser radiation and Rayleigh scattering. Two quartz convex lenses were used to collimate the light from the telescope from which the telescope-focusing eyepiece was removed, and direct it to the fiber optic assembly. To test the standoff sensing system, the Raman Telescope was used in the detection of liquid TIC: benzene, chlorobenzene, toluene, carbon tetrachloride, cyclohexane and carbon disulfide. Other compounds studied were CWAS: dimethylmethyl phosphonate, 2-chloroethyl ethyl sulfide and 2-(butylamino)-ethanethiol. Relative Raman scattering cross sections of liquid CWAS were measured using single-line sources at 532.0, 488.0, 363.8 and 351.1 nm. Samples were placed in glass and quartz vials at the standoff distances from the telescope for the Remote Raman measurements. The mass of DMMP present in water solutions was also quantified as part of the system performance tests.

  6. Chemical stress by different agents affects the melatonin content of barley roots.

    PubMed

    Arnao, Marino B; Hernández-Ruiz, Josefa

    2009-04-01

    The presence of melatonin (N-acetyl-5-methoxytryptamine) in plants has been clearly demonstrated. However, while this indoleamine has been intensively studied in animals, especially in mammals, the same is not true in the case of plants, where one of the most interesting aspects is its possible role as antioxidative molecule in physiological processes. Some data reflect the possible protective role that melatonin may exert in some stress situations such as ultraviolet (UV)-radiation, induced senescence and copper stress. The present work was designed to establish how the melatonin content changes in plants as a result of chemically induced stress. For this, barley plants were exposed in different treatments to the chemical-stress agents: sodium chloride, zinc sulphate or hydrogen peroxide. After different times, the content of melatonin in treated roots and control roots were determined using liquid chromatography (LC) with time-of-flight/mass spectrometry and LC with fluorescence detection for identification and quantification, respectively. The data show that the melatonin content in roots increased due to stress, reaching up to six times the melatonin content of control roots. Induction was time dependent, while hydrogen peroxide (10 mm) and zinc sulphate (1 mm) were the most effective inducers. The capacity of roots to absorb melatonin from soil was also studied. The data establish, for first time, that the chemical-stress agents assayed can induce the biosynthesis of melatonin in barley roots and produce a significant increase in their melatonin content. Such an increase in melatonin probably plays an important antioxidative role in the defense against chemically induced stress and other abiotic/biotic stresses. PMID:19196434

  7. Sensitive and comprehensive detection of chemical warfare agents in air by atmospheric pressure chemical ionization ion trap tandem mass spectrometry with counterflow introduction.

    PubMed

    Seto, Yasuo; Sekiguchi, Hiroshi; Maruko, Hisashi; Yamashiro, Shigeharu; Sano, Yasuhiro; Takayama, Yasuo; Sekioka, Ryoji; Yamaguchi, Shintaro; Kishi, Shintaro; Satoh, Takafumi; Sekiguchi, Hiroyuki; Iura, Kazumitsu; Nagashima, Hisayuki; Nagoya, Tomoki; Tsuge, Kouichiro; Ohsawa, Isaac; Okumura, Akihiko; Takada, Yasuaki; Ezawa, Naoya; Watanabe, Susumu; Hashimoto, Hiroaki

    2014-05-01

    A highly sensitive and specific real-time field-deployable detection technology, based on counterflow air introduction atmospheric pressure chemical ionization, has been developed for a wide range of chemical warfare agents (CWAs) comprising gaseous (two blood agents, three choking agents), volatile (six nerve gases and one precursor agent, five blister agents), and nonvolatile (three lachrymators, three vomiting agents) agents in air. The approach can afford effective chemical ionization, in both positive and negative ion modes, for ion trap multiple-stage mass spectrometry (MS(n)). The volatile and nonvolatile CWAs tested provided characteristic ions, which were fragmented into MS(3) product ions in positive and negative ion modes. Portions of the fragment ions were assigned by laboratory hybrid mass spectrometry (MS) composed of linear ion trap and high-resolution mass spectrometers. Gaseous agents were detected by MS or MS(2) in negative ion mode. The limits of detection for a 1 s measurement were typically at or below the microgram per cubic meter level except for chloropicrin (submilligram per cubic meter). Matrix effects by gasoline vapor resulted in minimal false-positive signals for all the CWAs and some signal suppression in the case of mustard gas. The moisture level did influence the measurement of the CWAs. PMID:24678766

  8. New adaptive methods for sensing of chemical components and biological agents

    NASA Astrophysics Data System (ADS)

    Yatsenko, Vitaliy A.; Chiarini, Bruno H.; Pardalos, Panos M.

    2004-02-01

    It is known that leaf reflectance spectra can be used to estimate the contents of chemical components in vegetation. Recent novel applications include the detection of harmful biological agents that can originate from agricultural bioterrorism attacks. Such attacks have been identified as a major threat to the United States" agriculture. Nevertheless, the usefulness of such approach is currently limited by distorting factors, in particular soil reflectance. The quantitative analysis of the spectral curves from the reflection of plant leaves may be the basis for the development of new methods for interpreting the data obtained by the remote measurement of plants. We consider the problem of characterizing the chemical composition from noisy spectral data using an experimental optical method. Using our experience in signal processing and optimization of complex systems we propose a new mathematical model for sensing of chemical components in vegetation. Estimates are defined as minimizers of penalized cost functionals with sequential quadratic programming (SQR) methods. A deviation measure used in risk analysis is also considered. This framework is demonstrated for different agricultural plants using adaptive filtration, principal components analysis, and optimization techniques for classification of spectral curves of chemical components. Various estimation problems will be considered to illustrate the computational aspects of the proposed method.

  9. Nanoparticle-Based Immunochromatographic Test Strip with Fluorescent Detector for Quantification of Phosphorylated Acetycholinesterase: An Exposure Biomarker of Organophosphorous Agents

    SciTech Connect

    Zhang, Weiying; Ge, Xiaoxiao; Tang, Yong; Du, Dan; Liu, Deli; Lin, Yuehe

    2013-09-21

    A nanoparticle-based fluorescence immunochromatographic test strip (FITS) coupled with a hand-held detector for highly selective and sensitive detection of phosphorylated acetylcholinesterase (AChE), an exposure biomarker of organophosphate (OP) pesticides and nerve agents, is reported. In this approach, OP-AChE adducts were selectively captured by quantum dot-tagged anti-AChE antibodies (Qdot-anti-AChE) and zirconia nanoparticles (ZrO2 NPs). The sandwich-like immunoreactions were performed among the Qdot-anti-AChE, OP-AChE and ZrO2 NPs to form Qdot-anti-AChE/OP-AChE/ZrO2 complex, which was detected by recording the fluorescence intensity of Qdot captured on the test line. Paraoxon was used as the model OP pesticides. Under optimal conditions, this portable FITS immunosensor demonstrates a highly linear absorption response over the range of 0.01 nM to 10 nM OP-AChE, with a detection limit of 4 pM, coupled with a good reproducibility. Moreover, the FITS immunosensor has been validated with OP-AChE spiked human plasma samples. This is the first report on the development of ZrO2 NPs-based FITS for detection of OP-AChE adduct. The FITS immunosensor provides a sensitive and low-cost sensing platform for on-site screening/evaluating OP pesticides and nerve agents poisoning.

  10. Treating exposure to chemical warfare agents: implications for health care providers and community emergency planning.

    PubMed Central

    Munro, N B; Watson, A P; Ambrose, K R; Griffin, G D

    1990-01-01

    Current treatment protocols for exposure to nerve and vesicant agents found in the U.S. stockpile of unitary chemical weapons are summarized, and the toxicities of available antidotes are evaluated. The status of the most promising of the new nerve agent antidotes is reviewed. In the U.S. atropine and pralidoxime compose the only approved antidote regimen for organophosphate nerve agent poisoning. Diazepam may also be used if necessary to control convulsions. To avoid death, administration must occur within minutes of substantial exposure together with immediate decontamination. Continuous observation and repeated administration of antidotes are necessary as symptoms warrant. Available antidotes do not necessarily prevent respiratory failure or incapacitation. The toxicity of the antidotes themselves and the individualized nature of medical care preclude recommending that autoinjectors be distributed to the general public. In addition, precautionary administration of protective drugs to the general population would not be feasible or desirable. No antidote exists for poisoning by the vesicant sulfur mustard (H, HD, HT); effective intervention can only be accomplished by rapid decontamination followed by palliative treatment of symptoms. British anti-Lewisite (BAL) (2,3-dimercapto-1-propanolol) is the antidote of choice for treatment of exposure to Lewisite, another potent vesicant. Experimental water-soluble BAL analogues have been developed that are less toxic than BAL. Treatment protocols for each antidote are summarized in tabular form for use by health care providers. PMID:2088748

  11. Treating exposure to chemical warfare agents: implications for health care providers and community emergency planning.

    PubMed

    Munro, N B; Watson, A P; Ambrose, K R; Griffin, G D

    1990-11-01

    Current treatment protocols for exposure to nerve and vesicant agents found in the U.S. stockpile of unitary chemical weapons are summarized, and the toxicities of available antidotes are evaluated. The status of the most promising of the new nerve agent antidotes is reviewed. In the U.S. atropine and pralidoxime compose the only approved antidote regimen for organophosphate nerve agent poisoning. Diazepam may also be used if necessary to control convulsions. To avoid death, administration must occur within minutes of substantial exposure together with immediate decontamination. Continuous observation and repeated administration of antidotes are necessary as symptoms warrant. Available antidotes do not necessarily prevent respiratory failure or incapacitation. The toxicity of the antidotes themselves and the individualized nature of medical care preclude recommending that autoinjectors be distributed to the general public. In addition, precautionary administration of protective drugs to the general population would not be feasible or desirable. No antidote exists for poisoning by the vesicant sulfur mustard (H, HD, HT); effective intervention can only be accomplished by rapid decontamination followed by palliative treatment of symptoms. British anti-Lewisite (BAL) (2,3-dimercapto-1-propanolol) is the antidote of choice for treatment of exposure to Lewisite, another potent vesicant. Experimental water-soluble BAL analogues have been developed that are less toxic than BAL. Treatment protocols for each antidote are summarized in tabular form for use by health care providers. PMID:2088748

  12. Treating exposure to chemical warfare agents: Implications for health care providers and community emergency planning

    SciTech Connect

    Munro, N.B.; Watson, A.P.; Ambrose, K.R.; Griffin, G.D. )

    1990-11-01

    Current treatment protocols for exposure to nerve and vesicant agents found in the US stockpile of unitary chemical weapons are summarized, and the toxicities of available antidotes are evaluated. The status of the most promising of the new nerve agent antidotes is reviewed. In the US, atropine and pralidoxime compose the only approved antidote regimen for organophosphate nerve agent poisoning. Diazepam may also be used if necessary to control convulsions. To avoid death, administration must occur within minutes of substantial exposure together with immediate decontamination. Continuous observation and repeated administration of antidotes are necessary as symptoms warrant. Available antidotes do not necessarily prevent respiratory failure or incapacitation. The toxicity of the antidotes themselves and the individualized nature of medical care preclude recommending that autoinjectors be distributed to the general public. In addition, precautionary administration of protective drugs to the general population would not be feasible or desirable. No antidote exists for poisoning by the vesicant sulfur mustard (H, HD, HT); effective intervention can only be accomplished by rapid decontamination followed by palliative treatment of symptoms. British anti-Lewisite (BAL) (2,3-dimercapto-1-propanol) is the antidote of choice for treatment of exposure to Lewisite, another potent vesicant. Experimental water-soluble BAL analogues have been developed that are less toxic than BAL. Treatment protocols for each antidote are summarized in tabular form for use by health care providers.

  13. Decontamination of chemical and biological warfare agents with a single multi-functional material.

    PubMed

    Amitai, Gabi; Murata, Hironobu; Andersen, Jill D; Koepsel, Richard R; Russell, Alan J

    2010-05-01

    We report the synthesis of new polymers based on a dimethylacrylamide-methacrylate (DMAA-MA) co-polymer backbone that support both chemical and biological agent decontamination. Polyurethanes containing the redox enzymes glucose oxidase and horseradish peroxidase can convert halide ions into active halogens and exert striking bactericidal activity against gram positive and gram negative bacteria. New materials combining those biopolymers with a family of N-alkyl 4-pyridinium aldoxime (4-PAM) halide-acrylate co-polymers offer both nucleophilic activity for the detoxification of organophosphorus nerve agents and internal sources of halide ions for generation of biocidal activity. Generation of free bromine and iodine was observed in the combined material resulting in bactericidal activity of the enzymatically formed free halogens that caused complete kill of E. coli (>6 log units reduction) within 1 h at 37 degrees C. Detoxification of diisopropylfluorophosphate (DFP) by the polyDMAA MA-4-PAM iodide component was dose-dependent reaching 85% within 30 min. A subset of 4-PAM-halide co-polymers was designed to serve as a controlled release reservoir for N-hydroxyethyl 4-PAM (HE 4-PAM) molecules that reactivate nerve agent-inhibited acetylcholinesterase (AChE). Release rates for HE 4-PAM were consistent with hydrolysis of the HE 4-PAM from the polymer backbone. The HE 4-PAM that was released from the polymer reactivated DFP-inhibited AChE at a similar rate to the oxime antidote 4-PAM. PMID:20199807

  14. Surface Decontamination of Chemical Agent Surrogates Using an Atmospheric Pressure Air Flow Plasma Jet

    NASA Astrophysics Data System (ADS)

    Li, Zhanguo; Li, Ying; Cao, Peng; Zhao, Hongjie

    2013-07-01

    An atmospheric pressure dielectric barrier discharge (DBD) plasma jet generator using air flow as the feedstock gas was applied to decontaminate the chemical agent surrogates on the surface of aluminum, stainless steel or iron plate painted with alkyd or PVC. The experimental results of material decontamination show that the residual chemical agent on the material is lower than the permissible value of the National Military Standard of China. In order to test the corrosion effect of the plasma jet on different material surfaces in the decontamination process, corrosion tests for the materials of polymethyl methacrylate, neoprene, polyvinyl chloride (PVC), polyethylene (PE), phenolic resin, iron plate painted with alkyd, stainless steel, aluminum, etc. were carried out, and relevant parameters were examined, including etiolation index, chromatism, loss of gloss, corrosion form, etc. The results show that the plasma jet is slightly corrosive for part of the materials, but their performances are not affected. A portable calculator, computer display, mainboard, circuit board of radiogram, and a hygrometer could work normally after being treated by the plasma jet.

  15. Stress, chemical defense agents, and cholinergic receptors. Midterm report, 1 November 1987-31 July 1989

    SciTech Connect

    Lane, J.D.

    1989-11-30

    This project is assessing the affects of exposure to a chemical defense agent on anxiety and stress, by using rat models of anxiety (conditioned emotional response (CER); conditioned suppression) and unconditioned non-specific stres (exposure to footshock). The specific experiments determined the plasticity of muscarinic cholinergic binding sites in the central nervous system. The neuroanatomical locus and neuropharmacological profile of changes in binding sites were assessed in brain areas enriched in cholinergic markers. Acetylcholine turnover was measured to determine if the receptor response is compensatory or independent. The effects of acute exposure to doses of a chemical defense agent (soman--XGD) on lethality and behaviors were examined. The experiments involved training and conditioning adult rats to CER using standard operant/respondent techniques. The binding of radiolabelled ligand was studied in vitro using brain membranes and tissue sections (autoradiography). The major findings are that CER produces increases in acetylcholine turnover in brain areas involved in anxiety, and that primarily post-synaptic M1 receptors compensatorly decrease in response. These neurochemical phenomena are directly correlated with several behaviors, including onset and extinction of CER and non-specific stress. Followup experiments have been designed to test the interaction of CER, XGD and neurochemistry.

  16. Identification of chemical warfare agents using a portable microchip-based detection device

    NASA Astrophysics Data System (ADS)

    Petkovic-Duran, K.; Swallow, A.; Sexton, B. A.; Glenn, F.; Zhu, Y.

    2011-12-01

    Analysis of chemical warfare agents (CWAs) and their degradation products is an important verification component in support of the Chemical Weapons Convention and urgently demanding rapid and reliable analytical methods. A portable microchip electrophoresis (ME) device with contactless conductivity (CCD) detection was developed for the in situ identification of CWA and their degradation products. A 10mM MES/His, 0.4mM CTAB - based separation electrolyte accomplished the analysis of Sarin (GB), Tabun( GA) and Soman (GD) in less than 1 min, which is the fastest screening of nerve agents achieved with portable ME and CCD based detection methods to date. Reproducibility of detection was successfully demonstrated on simultaneous detection of GB (200ppm) and GA (278ppm). Reasonable agreement for the four consecutive runs was achieved with the mean peak time for Sarin of 29.15s, and the standard error of 0.58s or 2%. GD and GA were simultaneously detected with their degradation products methylphosphonic acid (MPA), pinacolyl methylphosphonic acid (PMPA) and O-Ethyl Phosphorocyanidate (GAHP and GAHP1) respectively. The detection limit for Sarin was around 35ppb. To the best of our knowledge this is the best result achieved in microchip electrophoresis and contactless conductivity based detection to date.

  17. Water security: continuous monitoring of water distribution systems for chemical agents by SERS

    NASA Astrophysics Data System (ADS)

    Inscore, Frank; Shende, Chetan; Sengupta, Atanu; Farquharson, Stuart

    2007-04-01

    Ensuring safe water supplies requires continuous monitoring for potential poisons and portable analyzers to map distribution in the event of an attack. In the case of chemical warfare agents (CWAs) analyzers are needed that have sufficient sensitivity (part-per-billion), selectivity (differentiate the CWA from its hydrolysis products), and speed (less than 10 minutes) to be of value. We have been investigating the ability of surface-enhanced Raman spectroscopy (SERS) to meet these requirements by detecting CWAs and their hydrolysis products in water. The expected success of SERS is based on reported detection of single molecules, the one-to-one relationship between a chemical and its Raman spectrum, and the minimal sample preparation requirements. Recently, we have developed a simple sampling device designed to optimize the interaction of the target molecules with the SERS-active material with the goal of increasing sensitivity and decreasing sampling times. This sampling device employs a syringe to draw the water sample containing the analyte into a capillary filled with the SERS-active material. Recently we used such SERS-active capillaries to measure 1 ppb cyanide in water. Here we extend these measurements to nerve agent hydrolysis products using a portable Raman analyzer.

  18. Advances in toxicology and medical treatment of chemical warfare nerve agents.

    PubMed

    Moshiri, Mohammd; Darchini-Maragheh, Emadodin; Balali-Mood, Mahdi

    2012-01-01

    Organophosphorous (OP) Nerve agents (NAs) are known as the deadliest chemical warfare agents. They are divided into two classes of G and V agents. Most of them are liquid at room temperature. NAs chemical structures and mechanisms of actions are similar to OP pesticides, but their toxicities are higher than these compounds. The main mechanism of action is irreversible inhibition of Acetyl Choline Esterase (AChE) resulting in accumulation of toxic levels of acetylcholine (ACh) at the synaptic junctions and thus induces muscarinic and nicotinic receptors stimulation. However, other mechanisms have recently been described. Central nervous system (CNS) depression particularly on respiratory and vasomotor centers may induce respiratory failure and cardiac arrest. Intermediate syndrome after NAs exposure is less common than OP pesticides poisoning. There are four approaches to detect exposure to NAs in biological samples: (I) AChE activity measurement, (II) Determination of hydrolysis products in plasma and urine, (III) Fluoride reactivation of phosphylated binding sites and (IV) Mass spectrometric determination of cholinesterase adducts. The clinical manifestations are similar to OP pesticides poisoning, but with more severity and fatalities. The management should be started as soon as possible. The victims should immediately be removed from the field and treatment is commenced with auto-injector antidotes (atropine and oximes) such as MARK I kit. A 0.5% hypochlorite solution as well as novel products like M291 Resin kit, G117H and Phosphotriesterase isolated from soil bacterias, are now available for decontamination of NAs. Atropine and oximes are the well known antidotes that should be infused as clinically indicated. However, some new adjuvant and additional treatment such as magnesium sulfate, sodium bicarbonate, gacyclidine, benactyzine, tezampanel, hemoperfusion, antioxidants and bioscavengers have recently been used for OP NAs poisoning. PMID:23351280

  19. Common and distinct mechanisms of induced pulmonary fibrosis by particulate and soluble chemical fibrogenic agents

    PubMed Central

    Dong, Jie; Yu, Xiaoqing; Porter, Dale W.; Battelli, Lori A.; Kashon, Michael L.

    2016-01-01

    Pulmonary fibrosis results from the excessive deposition of collagen fibers and scarring in the lungs with or without an identifiable cause. The mechanism(s) underlying lung fibrosis development is poorly understood, and effective treatment is lacking. Here we compared mouse lung fibrosis induced by pulmonary exposure to prototypical particulate (crystalline silica) or soluble chemical (bleomycin or paraquat) fibrogenic agents to identify the underlying mechanisms. Young male C57BL/6J mice were given silica (2 mg), bleomycin (0.07 mg), or paraquat (0.02 mg) by pharyngeal aspiration. All treatments induced significant inflammatory infiltration and collagen deposition, manifesting fibrotic foci in silica-exposed lungs or diffuse fibrosis in bleomycin or paraquat-exposed lungs on day 7 post-exposure, at which time the lesions reached their peaks and represented a junction of transition from an acute response to chronic fibrosis. Lung genomewide gene expression was analyzed, and differential gene expression was confirmed by quantitative RT-PCR, immunohistochemistry, and immunoblotting for representative genes to demonstrate their induced expression and localization in fibrotic lungs. Canonical signaling pathways, gene ontology, and upstream transcription networks modified by each agent were identified. In particular, these inducers elicited marked proliferative responses; at the same time, silica preferentially activated innate immune functions and the defense against foreign bodies, whereas bleomycin and paraquat boosted responses related to cell adhesion, platelet activation, extracellular matrix remodeling, and wound healing. This study identified, for the first time, the shared and unique genes, signaling pathways, and biological functions regulated by particulate and soluble chemical fibrogenic agents during lung fibrosis, providing insights into the mechanisms underlying human lung fibrotic diseases. PMID:26345256

  20. Thiolates chemically induce redox activation of BTZ043 and related potent nitroaromatic anti-tuberculosis agents.

    PubMed

    Tiwari, Rohit; Moraski, Garrett C; Krchňák, Viktor; Miller, Patricia A; Colon-Martinez, Mariangelli; Herrero, Eliza; Oliver, Allen G; Miller, Marvin J

    2013-03-01

    The development of multidrug resistant (MDR) and extensively drug resistant (XDR) forms of tuberculosis (TB) has stimulated research efforts globally to expand the new drug pipeline. Nitroaromatic compounds, including 1,3-benzothiazin-4-ones (BTZs) and related agents, are a promising new class for the treatment of TB. Research has shown that the nitroso intermediates of BTZs that are generated in vivo cause suicide inhibition of decaprenylphosphoryl-β-D-ribose 2' oxidase (DprE1), which is responsible for cell wall arabinogalactan biosynthesis. We have designed and synthesized novel anti-TB agents inspired from BTZs and other nitroaromatic compounds. Computational studies indicated that the unsubstituted aromatic carbons of BTZ043 and related nitroaromatic compounds are the most electron-deficient and might be prone to nucleophilic attack. Our chemical studies on BTZ043 and the additional nitroaromatic compounds synthesized by us and others confirmed the postulated reactivity. The results indicate that nucleophiles such as thiolates, cyanide, and hydride induce nonenzymatic reduction of the nitro groups present in these compounds to the corresponding nitroso intermediates by addition at the unsubstituted electron-deficient aromatic carbon present in these compounds. Furthermore, we demonstrate here that these compounds are good candidates for the classical von Richter reaction. These chemical studies offer an alternate hypothesis for the mechanism of action of nitroaromatic anti-TB agents, in that the cysteine thiol(ate) or a hydride source at the active site of DprE1 may trigger the reduction of the nitro groups in a manner similar to the von Richter reaction to the nitroso intermediates, to initiate the inhibition of DprE1. PMID:23402278

  1. Advances in toxicology and medical treatment of chemical warfare nerve agents

    PubMed Central

    2012-01-01

    Organophosphorous (OP) Nerve agents (NAs) are known as the deadliest chemical warfare agents. They are divided into two classes of G and V agents. Most of them are liquid at room temperature. NAs chemical structures and mechanisms of actions are similar to OP pesticides, but their toxicities are higher than these compounds. The main mechanism of action is irreversible inhibition of Acetyl Choline Esterase (AChE) resulting in accumulation of toxic levels of acetylcholine (ACh) at the synaptic junctions and thus induces muscarinic and nicotinic receptors stimulation. However, other mechanisms have recently been described. Central nervous system (CNS) depression particularly on respiratory and vasomotor centers may induce respiratory failure and cardiac arrest. Intermediate syndrome after NAs exposure is less common than OP pesticides poisoning. There are four approaches to detect exposure to NAs in biological samples: (I) AChE activity measurement, (II) Determination of hydrolysis products in plasma and urine, (III) Fluoride reactivation of phosphylated binding sites and (IV) Mass spectrometric determination of cholinesterase adducts. The clinical manifestations are similar to OP pesticides poisoning, but with more severity and fatalities. The management should be started as soon as possible. The victims should immediately be removed from the field and treatment is commenced with auto-injector antidotes (atropine and oximes) such as MARK I kit. A 0.5% hypochlorite solution as well as novel products like M291 Resin kit, G117H and Phosphotriesterase isolated from soil bacterias, are now available for decontamination of NAs. Atropine and oximes are the well known antidotes that should be infused as clinically indicated. However, some new adjuvant and additional treatment such as magnesium sulfate, sodium bicarbonate, gacyclidine, benactyzine, tezampanel, hemoperfusion, antioxidants and bioscavengers have recently been used for OP NAs poisoning. PMID:23351280

  2. Common and distinct mechanisms of induced pulmonary fibrosis by particulate and soluble chemical fibrogenic agents.

    PubMed

    Dong, Jie; Yu, Xiaoqing; Porter, Dale W; Battelli, Lori A; Kashon, Michael L; Ma, Qiang

    2016-02-01

    Pulmonary fibrosis results from the excessive deposition of collagen fibers and scarring in the lungs with or without an identifiable cause. The mechanism(s) underlying lung fibrosis development is poorly understood, and effective treatment is lacking. Here we compared mouse lung fibrosis induced by pulmonary exposure to prototypical particulate (crystalline silica) or soluble chemical (bleomycin or paraquat) fibrogenic agents to identify the underlying mechanisms. Young male C57BL/6J mice were given silica (2 mg), bleomycin (0.07 mg), or paraquat (0.02 mg) by pharyngeal aspiration. All treatments induced significant inflammatory infiltration and collagen deposition, manifesting fibrotic foci in silica-exposed lungs or diffuse fibrosis in bleomycin or paraquat-exposed lungs on day 7 post-exposure, at which time the lesions reached their peaks and represented a junction of transition from an acute response to chronic fibrosis. Lung genome-wide gene expression was analyzed, and differential gene expression was confirmed by quantitative RT-PCR, immunohistochemistry, and immunoblotting for representative genes to demonstrate their induced expression and localization in fibrotic lungs. Canonical signaling pathways, gene ontology, and upstream transcription networks modified by each agent were identified. In particular, these inducers elicited marked proliferative responses; at the same time, silica preferentially activated innate immune functions and the defense against foreign bodies, whereas bleomycin and paraquat boosted responses related to cell adhesion, platelet activation, extracellular matrix remodeling, and wound healing. This study identified, for the first time, the shared and unique genes, signaling pathways, and biological functions regulated by particulate and soluble chemical fibrogenic agents during lung fibrosis, providing insights into the mechanisms underlying human lung fibrotic diseases. PMID:26345256

  3. Data for First Responder Use of Photoionization Detectors for Vapor Chemical Constituents

    SciTech Connect

    Keith A. Daum; Matthew G. Watrous; M. Dean Neptune; Daniel I. Michael; Kevin J. Hull; Joseph D. Evans

    2006-11-01

    First responders need appropriate measurement technologies for evaluating incident scenes. This report provides information about photoionization detectors (PIDs), obtained from manufacturers and independent laboratory tests, and the use of PIDs by first responders, obtained from incident commanders in the United States and Canada. PIDs are valued for their relatively low cost, light weight, rapid detection response, and ease of use. However, it is clear that further efforts are needed to provide suitable instruments and decision tools to incident commanders and first responders for assessing potential hazardous chemical releases. Information provided in this report indicates that PIDs should always be part of a decision-making context in which other qualitative and more definitive tests and instruments are used to confirm a finding. Possible amelioratory actions ranging from quick and relatively easy fixes to those requiring significant additional effort are outlined in the report.

  4. Disposal of chemical agents and munitions stored at Anniston Army Depot, Anniston, Alabama

    SciTech Connect

    Hunsaker, D.B. Jr.; Zimmerman, G.P.; Hillsman, E.L.; Miller, R.L.; Schoepfle, G.M.; Johnson, R.O.; Tolbert, V.R.; Kroodsma, R.L.; Rickert, L.W.; Rogers, G.O.; Staub, W.P.

    1990-09-01

    The purpose of this Phase I report is to examined the proposed implementation of on-site disposal at Anniston Army Depot (ANAD) in light of more detailed and more recent data than those included in the Final Programmatic Environmental Impact Statement (EPEIS). Two principal issues are addressed: (1) whether or not the new data would result in identification of on-site disposal at ANAD as the environmentally preferred alternative (using the same selection method and data analysis tools as in the FPEIS), and (2) whether or not the new data indicate the presence of significant environmental resources that could be affected by on-site disposal at ANAD. In addition, a status report is presented on the maturity of the disposal technology (and now it could affect on-site disposal at ANAD). Inclusion of these more recent data into the FPEIS decision method resulted in confirmation of on-site disposal for ANAD. No unique resources with the potential to prevent or delay implementation of on-site disposal at ANAD have been identified. A review of the technology status identified four principal technology developments that have occurred since publication of the FPEIS and should be of value in the implementation of on-site disposal at ANAD: the disposal of nonlethal agent at Pine Bluff Arsenal, located near Pine Bluff, Arkansas; construction and testing of facilities for disposal of stored lethal agent at Johnston Atoll, located about 1300 km (800 miles) southwest of Hawaii in the Pacific Ocean; lethal agent disposal tests at the chemical agent pilot plant operations at Tooele Army Depot, located near Salt Lake City, Utah; and equipment advances. 18 references, 13 figs., 10 tabs.

  5. Development of potent chemical antituberculosis agents targeting Mycobacterium tuberculosis acetohydroxyacid synthase.

    PubMed

    Jung, In-Pil; Ha, Na-Reum; Lee, Sang-Choon; Ryoo, Sung-Weon; Yoon, Moon-Young

    2016-09-01

    Mycobacterium tuberculosis acetohydroxyacid synthase (MTB-AHAS) has been suggested as a crucial target for antibacterial agents. High-throughput screening of a chemical library was performed to identify potent new inhibitors of MTB-AHAS. Among the 6800 tested compounds, 15 were identified as potent inhibitors, exhibiting >80-90% inhibition of in vitro MTB-AHAS activity at a fixed concentration of 20 µM. Five compounds belonging to the triazolopyrimidine structural class showed greater inhibition potency, with a half-maximum inhibition concentration (IC50 value) in the low micromolar range (0.4-1.24 µM). Furthermore, potent inhibitors demonstrated non-competitive, uncompetitive or mixed-competitive inhibition. Molecular docking experiments with these potent chemicals using a homology model of MTB-AHAS indicated hydrophobic and hydrogen bond interactions with some key herbicide binding site residues with binding energies (ΔG) of -8.04 to -10.68 Kcal/mol, respectively. The binding modes were consistent with inhibition mechanisms, as the chemicals were oriented outside the active site. Importantly, these potent inhibitors demonstrated significant growth inhibition of various clinically isolated multidrug-resistant and extensively drug-resistant M. tuberculosis strains, with 50% minimum inhibitory concentrations (MIC50 values) ranging from 0.2 µg/mL to 0.8 µg/mL, which resemble the MICs of conventional drugs for tuberculosis (isoniazid, 0.1 µg/mL; rifampicin, 0.4 µg/mL). Thus, the identified potent inhibitors show potential as scaffolds for further in vivo studies and might provide an impetus for the development of strong antituberculosis agents targeting MTB-AHAS. PMID:27451857

  6. Analysis of degradation products of chemical warfare agents using capillary electrophoresis.

    PubMed

    Aleksenko, Svetlana S; Gareil, Pierre; Timerbaev, Andrei R

    2011-10-21

    Analysis of chemical warfare agents (CWAs), their precursors and degradation products (DPs) is an important verification component in support of the Chemical Weapons Convention and urgently demanding rapid and reliable analytical methods. Considering a growing number of papers presented in the last years in the field of capillary electrophoresis (CE) of DPs, this review article gives an overview on CE techniques which are feasible for the determination of DPs with the advantages of using relatively simple and inexpensive research instrumentation, reduced consumption of potentially toxic samples, shorter sample preparation times, etc. A brief introduction is provided into the chemical background of CWAs followed by a documented appraisal that the CE method is well suited to deal with polar, acidic DPs mostly occurring in aqueous samples or extracts. Applications of CE to the separation of DPs are described, complemented by a critical discussion of the detection techniques, including mostly conductivity, laser-induced fluorescence, UV absorption and mass spectrometry. This review also includes actual development regarding the challenges of CE in analyses of different DPs from real samples, often avoided by in- and off-line pre-concentration techniques or the coupling of CE to selective detection methods. Special emphasis is placed on the miniaturised CE systems that have the potential of being before long developed into a field deployable and potentially disposable platform for routine DP monitoring in environmental samples. PMID:21858300

  7. Traction characteristics of chemical agent protective footwear soleing materials. Final technical report, October 1991-January 1993

    SciTech Connect

    Hall, R.

    1994-01-01

    The Static Coefficient of Friction (SCF) values were determined for several footwear soleing materials on different walkway surfaces, and for different surface conditions, to establish which soleing materials provided the best traction performance for shipboard application. The soleing materials evaluated included a standard Navy safety boot with nitrile rubber sole, a Vibram nitrile commercial sole, the Army's prototype nitrile/ neoprene multipurpose overboot (MULO) and vinyl overshoe, and three butyl chemical protective footwear covers. The walkway surfaces employed were stainless steel, aluminum, and new and worn non-skid coated steel. The SCF values were obtained with the surfaces dry, wet, and contaminated with oil. The ASTM Standard Test Method for Static Coefficient of Friction of Shoe Sole and Heel Materials, as measured by the James Machine, was used to determine the SCF values. The standard and MULO nitriles performed best when all walkway surfaces and conditions were considered. The excellent chemical resistance of the nitriles, and their high SCF values for a variety of surfaces and surface conditions evaluated in this study, makes them good candidate soleing materials for chemical agent protective footwear.

  8. A guide to the selection of personal protective equipment for use in responding to a release of chemical warfare agents

    SciTech Connect

    Foust, C.B.

    1997-10-01

    Recognition by the US Army that a potential threat to the public from continued storage was potentially as great a threat as from transportation and the final demilitarization of chemical agents gave rise to the Chemical Stockpile Emergency Preparedness Program (CSEPP). CSEPP is a civilian community emergency preparedness program complementing the Department of Defense`s initiative to destroy domestic stockpiles of aged chemical warface munitions. An incident involving chemical warfare agents requires a unique hazardous materials (HAZMAT) response. As with any HAZMAT event, federal regulations prescribe that responders must be protected from exposure to the chemical agents. But unlike other HAZMAT events, special considerations govern the selection of personal protective equipment (PPE). PPE includes all clothing, respirators and detection equipment used to respond to a chemical release. PPE can differ depending on whether responders are military or civilian personnel. FEMA requested that ORNL create training materials for CSEPP participants. These training materials were to provide information on a variety of topics and answer questions that a typical CSEPP participant might ask, including the following: how did the Army select the CSEPP recommended ensemble (i.e., protective clothing, respiratory equipment, and detection equipment); how does the CSEPP participant know this ensemble is the right PPE for chemical warfare agents and will actually protect him; what are the concept of operations and work rules? Does one need to know what the CSEPP concept of operations and work rules include? This report describes the training document ORNL created.

  9. Fabrication and characterization of silicon based thermal neutron detector with hot wire chemical vapor deposited boron carbide converter

    NASA Astrophysics Data System (ADS)

    Chaudhari, Pradip; Singh, Arvind; Topkar, Anita; Dusane, Rajiv

    2015-04-01

    In order to utilize the well established silicon detector technology for neutron detection application, a silicon based thermal neutron detector was fabricated by integrating a thin boron carbide layer as a neutron converter with a silicon PIN detector. Hot wire chemical vapor deposition (HWCVD), which is a low cost, low temperature process for deposition of thin films with precise thickness was explored as a technique for direct deposition of a boron carbide layer over the metalized front surface of the detector chip. The presence of B-C bonding and 10B isotope in the boron carbide film were confirmed by Fourier transform infrared spectroscopy and secondary ion mass spectrometry respectively. The deposition of HWCVD boron carbide layer being a low temperature process was observed not to cause degradation of the PIN detector. The response of the detector with 0.2 μm and 0.5 μm thick boron carbide layer was examined in a nuclear reactor. The pulse height spectrum shows evidence of thermal neutron response with signature of (n, α) reaction. The results presented in this article indicate that HWCVD boron carbide deposition technique would be suitable for low cost industrial fabrication of PIN based single element or 1D/2D position sensitive thermal neutron detectors.

  10. Neoplastic cell transformation by energetic heavy ions and its modification with chemical agents

    NASA Technical Reports Server (NTRS)

    Yang, T. C.; Tobias, C. A.

    1984-01-01

    One of the major deleterious late effects of ionizing radiation is related to the induction of neoplasms. In the present report recent experimental results on neoplastic cell transformation by heavy ions are presented, and possible means to circumvent the carcinogenic effect of space radiation are discussed. Biological effects observed in experiments involving the use of energetic heavy ions accelerated at the Bevalac suggest that many of the biological effects observed in earlier space flight experiments may be due to space radiation, particularly cosmic rays. It is found that the effect of radiation on cell transformation is dose-rate dependent. The frequency of neoplastic transformation for a given dose decreases with a decrease of dose rate of Co-60 gamma rays. It is found that various chemical agents give radiation protection, including DMSO.

  11. Method for Producing Chemically Bonded Phosphate Ceramics and for Stabilizing Contaminants Encapsulated therein Utilizing Reducing Agents

    SciTech Connect

    Singh, Dileep; Wagh, Arun S.; Jeong, Seung-Young

    1999-05-05

    Known phosphate ceramic formulations are improved and the ability to produce iron-based phosphate ceramic systems is enabled by the addition of an oxidizing or reducing step during the acid-base reactions that form the phosphate ceramic products. The additives allow control of the rate of the acid-base reactions and concomitant heat generation. In an alternate embodiment, waste containing metal anions is stabilized in phosphate ceramic products by the addition of a reducing agent to the phosphate ceramic mixture. The reduced metal ions are more stable and/or reactive with the phosphate ions, resulting in the formation of insoluble metal species within the phosphate ceramic matrix, such that the resulting chemically bonded phosphate ceramic product has greater leach resistance.

  12. Triage, monitoring, and treatment of mass casualty events involving chemical, biological, radiological, or nuclear agents

    PubMed Central

    Ramesh, Aruna C.; Kumar, S.

    2010-01-01

    In a mass casualty situation due to chemical, biological, radiological, or nuclear (CBRN) event, triage is absolutely required for categorizing the casualties in accordance with medical care priorities. Dealing with a CBRN event always starts at the local level. Even before the detection and analysis of agents can be undertaken, zoning, triage, decontamination, and treatment should be initiated promptly. While applying the triage system, the available medical resources and maximal utilization of medical assets should be taken into consideration by experienced triage officers who are most familiar with the natural course of the injury presented and have detailed information on medical assets. There are several triage systems that can be applied to CBRN casualties. With no one standardized system globally or nationally available, it is important for deploying a triage and decontamination system which is easy to follow and flexible to the available medical resources, casualty number, and severity of injury. PMID:21829319

  13. Mustard gas or sulfur mustard: an old chemical agent as a new terrorist threat.

    PubMed

    Wattana, Monica; Bey, Tareg

    2009-01-01

    Sulfur mustard is a member of the vesicant class of chemical warfare agents that causes blistering to the skin and mucous membranes. There is no specific antidote, and treatment consists of systematically alleviating symptoms. Historically, sulfur mustard was used extensively in inter-governmental conflicts within the trenches of Belgium and France during World War I and during the Iran-Iraq conflict. Longitudinal studies of exposed victims show that sulfur mustard causes long-term effects leading to high morbidity. Given that only a small amount of sulfur mustard is necessary to potentially cause an enormous number of casualties, disaster-planning protocol necessitates the education and training of first-line healthcare responders in the recognition, decontamination, triage, and treatment of sulfur mustard-exposed victims in a large-scale scenario. PMID:19557954

  14. Surface Decontamination of Simulated Chemical Warfare Agents Using a Nonequilibrium Plasma with Off-Gas Monitoring

    SciTech Connect

    Moeller, Trevor M.; Alexander, M. Lizabeth; Engelhard, Mark H.; Gaspar, Dan J.; Luna, Maria L.; Irving, Patricia M.

    2002-08-01

    InnovaTek is developing a surface decontamination technology that utilizes active species generated in a nonequilibrium corona plasma. The plasma technology was tested against DMMP, a simulant for the chemical agent Sarin. GC-MS analysis showed that a greater than four log10 destruction of the DMMP on an aluminum surface was achieved in a 10 minute treatment. An ion-trap mass spectrometer was utilized to collect time-resolved data on the treatment off-gases. These data indicate that only non-toxic fragments of the broken down DMMP molecule were present in the gas phase. The technology is being further refined to develop a product that will not only decontaminate surfaces but will also sense when decontamination is complete

  15. Deep Raman spectroscopy for the non-invasive standoff detection of concealed chemical threat agents.

    PubMed

    Izake, Emad L; Cletus, Biju; Olds, William; Sundarajoo, Shankaran; Fredericks, Peter M; Jaatinen, Esa

    2012-05-30

    Deep Raman spectroscopy has been utilized for the standoff detection of concealed chemical threat agents from a distance of 15 m under real life background illumination conditions. By using combined time and space resolved measurements, various explosive precursors hidden in opaque plastic containers were identified non-invasively. Our results confirm that combined time and space resolved Raman spectroscopy leads to higher selectivity towards the sub-layer over the surface layer as well as enhanced rejection of fluorescence from the container surface when compared to standoff spatially offset Raman spectroscopy. Raman spectra that have minimal interference from the packaging material and good signal-to-noise ratio were acquired within 5 s of measurement time. A new combined time and space resolved Raman spectrometer has been designed with nanosecond laser excitation and gated detection, making it of lower cost and complexity than picosecond-based laboratory systems. PMID:22608458

  16. Method for producing chemically bonded phosphate ceramics and for stabilizing contaminants encapsulated therein utilizing reducing agents

    DOEpatents

    Singh, Dileep; Wagh, Arun S.; Jeong, Seung-Young

    2000-01-01

    Known phosphate ceramic formulations are improved and the ability to produce iron-based phosphate ceramic systems is enabled by the addition of an oxidizing or reducing step during the acid-base reactions that form the phosphate ceramic products. The additives allow control of the rate of the acid-base reactions and concomitant heat generation. In an alternate embodiment, waste containing metal anions are stabilized in phosphate ceramic products by the addition of a reducing agent to the phosphate ceramic mixture. The reduced metal ions are more stable and/or reactive with the phosphate ions, resulting in the formation of insoluble metal species within the phosphate ceramic matrix, such that the resulting chemically bonded phosphate ceramic product has greater leach resistance.

  17. Comparison of the lethal effects of chemical warfare nerve agents across multiple ages.

    PubMed

    Wright, Linnzi K M; Lee, Robyn B; Vincelli, Nicole M; Whalley, Christopher E; Lumley, Lucille A

    2016-01-22

    Children may be inherently more vulnerable than adults to the lethal effects associated with chemical warfare nerve agent (CWNA) exposure because of their closer proximity to the ground, smaller body mass, higher respiratory rate, increased skin permeability and immature metabolic systems. Unfortunately, there have only been a handful of studies on the effects of CWNA in pediatric animal models, and more research is needed to confirm this hypothesis. Using a stagewise, adaptive dose design, we estimated the 24h median lethal dose for subcutaneous exposure to seven CWNA in both male and female Sprague-Dawley rats at six different developmental times. Perinatal (postnatal day [PND] 7, 14 and 21) and adult (PND 70) rats were more susceptible than pubertal (PND 28 and 42) rats to the lethal effects associated with exposure to tabun, sarin, soman and cyclosarin. Age-related differences in susceptibility were not observed in rats exposed to VM, Russian VX or VX. PMID:26621540

  18. Trapping of organophosphorus chemical nerve agents in water with amino acid functionalized baskets.

    PubMed

    Ruan, Yian; Dalkiliç, Erdin; Peterson, Paul W; Pandit, Aroh; Dastan, Arif; Brown, Jason D; Polen, Shane M; Hadad, Christopher M; Badjić, Jovica D

    2014-04-01

    We prepared eleven amino-acid functionalized baskets and used (1) H NMR spectroscopy to quantify their affinity for entrapping dimethyl methylphosphonate (DMMP, 118 Å(3) ) in aqueous phosphate buffer at pH=7.0±0.1; note that DMMP guest is akin in size to chemical nerve agent sarin (132 Å(3) ). The binding interaction (Ka ) was found to vary with the size of substituent groups at the basket's rim. In particular, the degree of branching at the first carbon of each substituent had the greatest effect on the host-guest interaction, as described with the Verloop's B1 steric parameter. The branching at the remote carbons, however, did not perturb the encapsulation, which is important for guiding the design of more effective hosts and catalysts in future. PMID:24616086

  19. Design and evaluation of hyperspectral algorithms for chemical warfare agent detection

    NASA Astrophysics Data System (ADS)

    Manolakis, Dimitris; D'Amico, Francis M.

    2005-11-01

    Remote sensing of chemical warfare agents (CWA) with stand-off hyperspectral imaging sensors has a wide range of civilian and military applications. These sensors exploit the spectral changes in the ambient photon flux produced by either sunlight or the thermal emission of the earth after passage through a region containing the CWA cloud. The purpose of this paper is threefold. First, to discuss a simple phenomenological model for the radiance measured by the sensor in the case of optically thin clouds. This model provides the mathematical framework for the development of optimum algorithms and their analytical evaluation. Second, we identify the fundamental aspects of the data exploitation problem and we develop detection algorithms that can be used by different sensors as long as they can provide the required measurements. Finally, we discuss performance metrics for detection, identification, and quantification and we investigate their dependance on CWA spectral signatures, sensor noise, and background spectral variability.

  20. Using Mode of Action to Assess Health Risks from Mixtures of Chemical/Physical Agents

    SciTech Connect

    Bull, Richard J.; Lei, Xingye C.; Sasser, Lyle B.

    2003-01-20

    a low, but effective, dose of one agent was superimposed on a high dose of another. When given at high doses, the effects were generally no greater than observed with either agent alone. A low dose of TCA was clearly antagonistic to a high dose of DCA. This antagonism carried throughout the dose response curve for TCA. Apparently, these interactions involve some subtle modification of effects by one chemical in cells responsive to the other chemical. Consequently, our findings do not argue that interactions will extend below the effective doses of either chemical.

  1. Chemical characterization and ecotoxicity of three soil foaming agents used in mechanized tunneling.

    PubMed

    Baderna, Diego; Lomazzi, Eleonora; Passoni, Alice; Pogliaghi, Alberto; Petoumenou, Maria Ifigeneia; Bagnati, Renzo; Lodi, Marco; Viarengo, Aldo; Sforzini, Susanna; Benfenati, Emilio; Fanelli, Roberto

    2015-10-15

    The construction of tunnels and rocks with mechanized drills produces several tons of rocky debris that are today recycled as construction material or as soil replacement for covering rocky areas. The lack of accurate information about the environmental impact of these excavated rocks and foaming agents added during the excavation process has aroused increasing concern for ecosystems and human health. The present study proposes an integrated approach to the assessment of the potential environmental impact of three foaming agents containing different anionic surfactants and other polymers currently on the market and used in tunnel boring machines. The strategy includes chemical characterization with high resolution mass spectrometry techniques to identify the components of each product, the use of in silico tools to perform a similarity comparison among these compounds and some pollutants already listed in regulatory frameworks to identify possible threshold concentrations of contamination, and the application of a battery of ecotoxicological assays to investigate the impact of each foaming mixture on model organisms of soil (higher plants and Eisenia andrei) and water communities (Daphnia magna). The study identified eleven compounds not listed on the material safety data sheets for which we have identified possible concentrations of contamination based on existing regulatory references. The bioassays allowed us to determine the no effect concentrations (NOAECs) of the three mixtures, which were subsequently used as threshold concentration for the product in its entirety. The technical mixtures used in this study have a different degree of toxicity and the predicted environmental concentrations based on the conditions of use are lower than the NOAEC for soils but higher than the NOAEC for water, posing a potential risk to the waters due to the levels of foaming agents in the muck. PMID:25917697

  2. Chiral Separation of G-type Chemical Warfare Nerve Agents via Analytical Supercritical Fluid Chromatography

    PubMed Central

    Kasten, Shane A; Zulli, Steven; Jones, Jonathan L; Dephillipo, Thomas; Cerasoli, Douglas M

    2014-01-01

    Chemical warfare nerve agents (CWNAs) are extremely toxic organophosphorus compounds that contain a chiral phosphorus center. Undirected synthesis of G-type CWNAs produces stereoisomers of tabun, sarin, soman, and cyclosarin (GA, GB, GD, and GF, respectively). Analytical-scale methods were developed using a supercritical fluid chromatography (SFC) system in tandem with a mass spectrometer for the separation, quantitation, and isolation of individual stereoisomers of GA, GB, GD, and GF. Screening various chiral stationary phases (CSPs) for the capacity to provide full baseline separation of the CWNAs revealed that a Regis WhelkO1 (SS) column was capable of separating the enantiomers of GA, GB, and GF, with elution of the P(+) enantiomer preceding elution of the corresponding P(–) enantiomer; two WhelkO1 (SS) columns had to be connected in series to achieve complete baseline resolution. The four diastereomers of GD were also resolved using two tandem WhelkO1 (SS) columns, with complete baseline separation of the two P(+) epimers. A single WhelkO1 (RR) column with inverse stereochemistry resulted in baseline separation of the GD P(–) epimers. The analytical methods described can be scaled to allow isolation of individual stereoisomers to assist in screening and development of countermeasures to organophosphorus nerve agents. Chirality 26:817–824, 2014. © 2014 The Authors. Chirality published by John Wiley Periodicals, Inc. PMID:25298066

  3. Surface studies of aminoferrocene derivatives on gold: electrochemical sensors for chemical warfare agents.

    PubMed

    Khan, Mohammad A K; Long, Yi-Tao; Schatte, Gabriele; Kraatz, Heinz-Bernhard

    2007-04-01

    The cystamine conjugate [(BocNH)Fc(CO)CSA]2 was prepared by coupling cystamine with the N-protected ferrocene amino acid derivative BocHN-Fc-COOH and was fully characterized by spectroscopic methods and by single-crystal X-ray diffraction. The cystamine conjugate forms films on gold substrates, which upon deprotection of the amino group, react with chemical warfare agent (CWA) mimics, upon which the redox properties of the Fc group are affected significantly. Cyclic voltammetry shows 50(5) mV anodic shifts of the Fc redox potentials after exposure to EtSCH2CH2Cl, a simulant for sulfur mustard HD (MA), and (NC)(EtO)2P(O), a simulant for nerve agent Tabun (NA). Exposure to MA and NA causes an increase in 2.3 and 4.5 ng mass, respectively, in QCM which indicates ca. 70% efficiency in Boc-deprotection. Ellipsometry measured a film thickness increase from 6(+/-1) A for the deprotected film to 10(+/-4) A for the film modified with MA and to 7(+/-2) A for the film modified with NA. AFM measurements show changes in the thickness and morphology of the film after reaction with MA and NA. The surfaces were analyzed by X-ray photoelectron spectroscopy (XPS) and clearly show the attachment of the cystamine conjugate on the surface and its reaction with CWA mimics. PMID:17319647

  4. Investigation of chemical bath deposition of CdO thin films using three different complexing agents

    NASA Astrophysics Data System (ADS)

    Khallaf, Hani; Chen, Chia-Ta; Chang, Liann-Be; Lupan, Oleg; Dutta, Aniruddha; Heinrich, Helge; Shenouda, A.; Chow, Lee

    2011-09-01

    Chemical bath deposition of CdO thin films using three different complexing agents, namely ammonia, ethanolamine, and methylamine is investigated. CdSO 4 is used as Cd precursor, while H 2O 2 is used as an oxidation agent. As-grown films are mainly cubic CdO 2, with some Cd(OH) 2 as well as CdO phases being detected. Annealing at 400 °C in air for 1 h transforms films into cubic CdO. The calculated optical band gap of as-grown films is in the range of 3.37-4.64 eV. Annealed films have a band gap of about 2.53 eV. Rutherford backscattering spectroscopy of as-grown films reveals cadmium to oxygen ratio of 1.00:1.74 ± 0.01 while much better stoichiometry is obtained after annealing, in accordance with the X-ray diffraction results. A carrier density as high as 1.89 × 10 20 cm -3 and a resistivity as low as 1.04 × 10 -2 Ω-cm are obtained.

  5. Mass spectrometric study of selected precursors and degradation products of chemical warfare agents.

    PubMed

    Papousková, Barbora; Bednár, Petr; Frysová, Iveta; Stýskala, Jakub; Hlavác, Jan; Barták, Petr; Ulrichová, Jitka; Jirkovský, Jaromír; Lemr, Karel

    2007-12-01

    Selected precursors and degradation products of chemical warfare agents namely N,N-dialkylaminoethane-2-ols, N,N-dialkylaminoethyl-2-chlorides and some of related N-quaternary salts were studied by means of electrospray ionization-multiple tandem mass spectrometry (ESI-MS(n)). Proposed structures were confirmed with accurate mass measurement. General fragmentation patterns of these compounds are discussed in detail and suggested processes are confirmed using deuterated standards. The typical processes are elimination of alkene, hydrogen chloride, or water, respectively. Besides, elimination of ethene from propyl chain under specific conditions was observed and unambiguously confirmed using exact mass measurement and labelled standard. The potential of mass spectrometry to distinguish the positional isomers occurring among the studied compounds is reviewed in detail using two different MS instruments (i.e. ion trap and hybrid quadrupole-time of flight (Q-TOF) analyzer). A new microcolumn liquid chromatography (microLC)/MS(n) method was designed for the cases where the resolution based solely on differences in fragmentation is not sufficient. Low retention of the derivatives on reversed phase (RP) was overcome by using addition of less typical ion pairing agent (1 mM/l, 3,5-dinitrobenzoic acid) to the mobile phase (mixture water : acetonitrile). PMID:18085550

  6. Separation of thiol and cyanide hydrolysis products of chemical warfare agents by capillary electrophoresis.

    PubMed

    Copper, Christine L; Collins, Greg E

    2004-03-01

    The fluorescence derivatizing agent, o-phthalaldehyde (OPA), has been applied to the separation and detection of cyanide and several structurally similar thiols by capillary electrophoresis (CE)-laser induced fluorescence (LIF). Of particular interest to this investigation was the separation of 2-dimethylaminoethanethiol, 2-diethylaminoethanethiol, and cyanide, each of which are hydrolysis products or hydrolysis product simulants of the chemical warfare (CW) agents O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX), O-isobutyl S-2-diethylaminoethyl methylphosphonothiolate (R-VX), and tabun (GA). Other structurally similar thiols simultaneously resolved by this method include 1-pentanethiol and 2-mercaptoethanol. Instrumental parameters were probed and optimum values for capillary length (50 cm) and inner diameter (75 microm), injection time (30 s) and field strength (15 kV) were determined. Sample stacking methods enabled detection limits of 9.3 microg/L for cyanide, 1.8 microg/L for 2-diethylaminoethanethiol, 35 microg/L for 2-dimethylaminoethanethiol, 15 microg/L for 2-mercaptoethanol, and 89 microg/L for 1-pentanethiol. The linearity of the method was verified over an order of magnitude and the reproducibility was found to be 3.0%. PMID:15004852

  7. Water-driven micromotors for rapid photocatalytic degradation of biological and chemical warfare agents.

    PubMed

    Li, Jinxing; Singh, Virendra V; Sattayasamitsathit, Sirilak; Orozco, Jahir; Kaufmann, Kevin; Dong, Renfeng; Gao, Wei; Jurado-Sanchez, Beatriz; Fedorak, Yuri; Wang, Joseph

    2014-11-25

    Threats of chemical and biological warfare agents (CBWA) represent a serious global concern and require rapid and efficient neutralization methods. We present a highly effective micromotor strategy for photocatalytic degradation of CBWA based on light-activated TiO2/Au/Mg microspheres that propel autonomously in natural water and obviate the need for external fuel, decontaminating reagent, or mechanical agitation. The activated TiO2/Au/Mg micromotors generate highly reactive oxygen species responsible for the efficient destruction of the cell membranes of the anthrax simulant Bacillus globigii spore, as well as rapid and complete in situ mineralization of the highly persistent organophosphate nerve agents into nonharmful products. The water-driven propulsion of the TiO2/Au/Mg micromotors facilitates efficient fluid transport and dispersion of the photogenerated reactive oxidative species and their interaction with the CBWA. Coupling of the photocatalytic surface of the micromotors and their autonomous water-driven propulsion thus leads to a reagent-free operation which holds a considerable promise for diverse "green" defense and environmental applications. PMID:25289459

  8. Chemical agent simulants for testing transparent materials. Contractor report, September 1987-January 1988

    SciTech Connect

    Lewis, R.E.; Liebman, S.A.; Isaacson, L.; Grasso, P.S.; Sarver, E.W.

    1988-05-01

    Transparent polymeric materials undergo physical changes when exposed to chemical warfare agents. The object of this task was to: 1) select candidate liquids to simulate GB, VX and HD effects (three each) and 2) perform three point bend tests to determine critical strain values for cracking/crazing for simulant/transparent-polymer materials combinations. The critical-strain tests were accomplished using ASTM method D790-80 for stress crazing. The method was modified and enhanced to detect stress crazing via changes in reflection/diffraction patterns produced with a helium-neon (He-Ne) laser. Four transparent-polymer materials were tested; namely, as cast polymethyl methacrylate (PMMA), biaxially stretched PMMA, polycarbonate and polyurethane GAC-590. The critical-strain values obtained for the simulant/polymer combinations are presented as a four-by-nine map that allows easy comparisons as a function of material or simulant. Comparison with actual agent data is possible using this four-by-nine map.

  9. Decontamination of Chemical/Biological Warfare (CBW) Agents Using an Atmospheric Pressure Plasma Jet (APPJ)

    NASA Astrophysics Data System (ADS)

    Herrmann, Hans W.

    1998-11-01

    The atmospheric pressure plasma jet (APPJ) is a non-thermal, high pressure, uniform glow discharge that produces a high velocity effluent stream of highly reactive chemical species. The discharge operates on a feedstock gas (e.g. He/O_2/H_2O) 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 metastables (e.g. O2*, He*) and radicals (e.g. O, OH). These reactive species have been shown to be effective neutralizers of surrogates for anthrax spores, mustard blister agent and VX nerve gas. Unlike conventional, wet decontamination methods, the plasma effluent does not cause corrosion of most surfaces and does not damage wiring, electronics, nor most plastics. This makes it highly suitable for decontamination of high value sensitive equipment such as is found in vehicle interiors (i.e. tanks, planes...) for which there is currently no good decontamination technique. Furthermore, the reactive species rapidly degrade into harmless products leaving no lingering residue or harmful byproducts. Physics of the APPJ will be discussed and results of surface decontamination experiments using simulant and actual CBW agents will be presented.

  10. Effects on titanium implant surfaces of chemical agents used for the treatment of peri-implantitis.

    PubMed

    Ungvári, Krisztina; Pelsöczi, István K; Kormos, Bernadett; Oszkó, Albert; Rakonczay, Zoltán; Kemény, Lajos; Radnai, Márta; Nagy, Katalin; Fazekas, András; Turzó, Kinga

    2010-07-01

    The treatment of peri-implantitis, which causes tissue deterioration surrounding osseointegrated implants, involves surface decontamination and cleaning. However, chemical cleaning agents may alter the structure of implant surfaces. We investigated three such cleaning solutions. Commercially pure (grade 4) machined titanium discs (CAMLOG Biotechnologies AG, Switzerland) were treated with 3% H(2)O(2) (5 min), saturated citric acid (pH = 1) (1 min) or chlorhexidine gel (5 min), and their surface properties were examined by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Human epithelial cell attachment (24-h observation) and proliferation (72-h observation) were investigated via dimethylthiazolyl-diphenyltetrazolium bromide (MTT) and bicinchoninic acid (BCA) protein content assays. AFM revealed no significant difference in roughness of the three treated surfaces. XPS confirmed the constant presence of typical surface elements and an intact TiO(2) layer on each surface. The XPS peaks after chlorhexidine gel treatment demonstrated C-O and/or C=O bond formation, due to chlorhexidine digluconate infiltrating the surface. MTT and BCA assays indicated similar epithelial cell attachments in the three groups; epithelial cell proliferation being significantly higher after H(2)O(2) than after chlorhexidine gel treatment (not shown by BCA assays). These agents do not harm the Ti surface. Cleaning with H(2)O(2) slightly enhances human epithelial cell growth, in contrast to chlorhexidine gel. PMID:20524198

  11. A Chemical Detector for Gas Chromatography Using Pulsed Discharge Emission Spectroscopy on a Microchip

    NASA Astrophysics Data System (ADS)

    Luo, X.; Zhu, W.; Mitra, B.; Liu, J.; Liu, T.; Fan, X.; Gianchandani, Y.

    2011-12-01

    There is increasing interest in miniaturized systems for chemical analysis in harsh environments. Chemical detection by emission spectroscopy of on-chip microdischarges [1-3] can be performed at >200°C [4], suggesting utility inspace exploration, volcanic monitoring, and oil well monitoring. This abstract describes the first use of pulsed microdischarge spectroscopy for gas chromatography (GC).This effort supports NASA interests in monitoring closed-loop life support systems for spacecraft. The microdischarge occurs on a 1cm2 glass chip (Fig. 1a), with thin-film Ni electrodes separated by 160μm. A glass lid with a grooved gas-flow channel, and inlet/outlet capillary tubes are epoxy-sealed to the chip. Located downstream of the 1.7m-long, RTX-1-coated, GC separation column, the microdischarge chip is read by a spectrometer. In a typical experiment (Fig. 1b), a mixture of acetone 3.6μg, 1-hexanol 2.8μg and nitrobenzene 3.0μg, is injected, with He carrier gas at 1.56sccm, through the GC. Acetone elutes quickly while nitrobenzene is slower. Microdischarges are triggered at 0.5Hz for 6 min., and 0.04Hz thereafter. Each microdischarge consumes ≈8mJ; the average power is ≈1.14mW. The spectrum (Fig. 1b, inset) shows that the 388nm peak, representing CN/CH fragments [5], is enhanced by carbon compounds. Its strength relative to the 588nm peak of He provides a chromatogram. Fig. 1b also shows a benchmark result from a commercial flame ionization detector (FID). The differences in elution time are attributed to differences in the gas flow paths for the two detectors [1]. REFERENCES [1] Eijkel et al, Anal. Chem, 2000 [2] Mitra et al, IEEE Trans Plasma Sci, 2008 [3] Mitra et al, IEEE Sensors, 2008 [4] Wright et al, APL, 2009 [5] Pearse et al, The Identification of Molecular Spectra, 1963

  12. Saffron as an antidote or a protective agent against natural or chemical toxicities.

    PubMed

    Razavi, Bibi Marjan; Hosseinzadeh, Hossein

    2015-01-01

    Saffron (Crocus sativus) is an extensively used food additive for its color and taste. Since ancient times this plant has been introduced as a marvelous medicine throughout the world. The wide spectrum of saffron pharmacological activities is related to its major constituents including crocin, crocetin and safranal. Based on several studies, saffron and its active ingredients have been used as an antioxidant, antiinflammatory and antinociceptive, antidepressant, antitussive, anticonvulsant, memory enhancer, hypotensive and anticancer. According to the literatures, saffron has remarkable therapeutic effects. The protective effects of saffron and its main constituents in different tissues including brain, heart, liver, kidney and lung have been reported against some toxic materials either natural or chemical toxins in animal studies.In this review article, we have summarized different in vitro and animal studies in scientific databases which investigate the antidotal and protective effects of saffron and its major components against natural toxins and chemical-induced toxicities. Due to the lake of human studies, further investigations are required to ascertain the efficacy of saffron as an antidote or a protective agent in human intoxication. PMID:25928729

  13. Modified clay minerals efficiency against chemical and biological warfare agents for civil human protection.

    PubMed

    Plachá, Daniela; Rosenbergová, Kateřina; Slabotínský, Jiří; Kutláková, Kateřina Mamulová; Studentová, Soňa; Martynková, Gražyna Simha

    2014-04-30

    Sorption efficiencies of modified montmorillonite and vermiculite of their mono ionic Na and organic HDTMA and HDP forms were studied against chemical and biological warfare agents such as yperite and selected bacterial strains. Yperite interactions with modified clay minerals were observed through its capture in low-density polyethylene foil-modified clay composites by measuring yperite gas permeation with using chemical indication and gas chromatography methods. The antibacterial activities of synthetized organoclays were tested against selected Gram-positive and Gram-negative bacterial species in minimum inhibitory concentration tests. The obtained results showed a positive influence of modified clay minerals on the significant yperite breakthrough-time increase. The most effective material was the polyethylene-Na form montmorillonite, while the polyethylene-Na form vermiculite showed the lowest efficiency. With increasing organic cations loading in the interlayer space the montmorillonite efficiency decreased, and in the case of vermiculite an opposite effect was observed. Generally the modified montmorillonites were more effective than modified vermiculites. The HDP cations seem to be more effective compare to the HDTMA. The antibacterial activity tests confirmed efficiency of all organically modified clay minerals against Gram-positive bacteria. The confirmation of antibacterial activity against Y. pestis, plague bacteria, is the most interesting result of this part of the study. PMID:24603112

  14. Functionalized gold nanoparticle supported sensory mechanisms applied in detection of chemical and biological threat agents: a review.

    PubMed

    Upadhyayula, Venkata K K

    2012-02-17

    There is a great necessity for development of novel sensory concepts supportive of smart sensing capabilities in defense and homeland security applications for detection of chemical and biological threat agents. A smart sensor is a detection device that can exhibit important features such as speed, sensitivity, selectivity, portability, and more importantly, simplicity in identifying a target analyte. Emerging nanomaterial based sensors, particularly those developed by utilizing functionalized gold nanoparticles (GNPs) as a sensing component potentially offer many desirable features needed for threat agent detection. The sensitiveness of physical properties expressed by GNPs, e.g. color, surface plasmon resonance, electrical conductivity and binding affinity are significantly enhanced when they are subjected to functionalization with an appropriate metal, organic or biomolecular functional groups. This sensitive nature of functionalized GNPs can be potentially exploited in the design of threat agent detection devices with smart sensing capabilities. In the presence of a target analyte (i.e., a chemical or biological threat agent) a change proportional to concentration of the analyte is observed, which can be measured either by colorimetric, fluorimetric, electrochemical or spectroscopic means. This article provides a review of how functionally modified gold colloids are applied in the detection of a broad range of threat agents, including radioactive substances, explosive compounds, chemical warfare agents, biotoxins, and biothreat pathogens through any of the four sensory means mentioned previously. PMID:22244163

  15. Project swiftsure final report: Destruction of chemical agent waste at Defence Research Establishment Suffield. Suffield special publication No. 170

    SciTech Connect

    McAndless, J.M.

    1995-12-31

    Swiftsure was a project to destroy old chemical warfare agent waste at the Defence Research Establishment Suffield Experimental Proving Ground. This report begins with an overview of the project and the consultation process, and describes the project planning and development process, the methods used to destroy the nerve agents, the contracting of a waste incinerator, the environmental protection plan, incinerator installation and testing, waste preparation and incineration operations, final waste product disposal and the environmental monitoring program. Appendices include details on the properties of the agents destroyed, sampling and analysis methods, and air quality monitoring specifications.

  16. New method for comprehensive detection of chemical warfare agents using an electron-cyclotron-resonance ion-source mass spectrometer.

    PubMed

    Kidera, Masanori; Seto, Yasuo; Takahashi, Kazuya; Enomoto, Shuichi; Kishi, Shintaro; Makita, Mika; Nagamatsu, Tsuyoshi; Tanaka, Tatsuhiko; Toda, Masayoshi

    2011-03-01

    We developed a detection technology for vapor forms of chemical warfare agents (CWAs) with an element analysis system using an electron cyclotron resonance ion source. After the vapor sample was introduced directly into the ion source, the molecular material was decomposed into elements using electron cyclotron resonance plasma and ionized. The following CWAs and stimulants were examined: diisopropyl fluorophosphonate (DFP), 2-chloroethylethylsulfide (2CEES), cyanogen chloride (CNCl), and hydrogen cyanide (HCN). The type of chemical warfare agents, specifically, whether it was a nerve agent, blister agent, blood agent, or choking agent, could be determined by measuring the quantities of the monatomic ions or CN(+) using mass spectrometry. It was possible to detect gaseous CWAs that could not be detected by a conventional mass spectrometer. The distribution of electron temperature in the plasma could be closely controlled by adjusting the input power of the microwaves used to generate the electron cyclotron resonance plasma, and the target compounds could be detected as molecular ions or fragment ions, enabling identification of the target agents. PMID:21242103

  17. New method for comprehensive detection of chemical warfare agents using an electron-cyclotron-resonance ion-source mass spectrometer

    NASA Astrophysics Data System (ADS)

    Kidera, Masanori; Seto, Yasuo; Takahashi, Kazuya; Enomoto, Shuichi; Kishi, Shintaro; Makita, Mika; Nagamatsu, Tsuyoshi; Tanaka, Tatsuhiko; Toda, Masayoshi

    2011-03-01

    We developed a detection technology for vapor forms of chemical warfare agents (CWAs) with an element analysis system using an electron cyclotron resonance ion source. After the vapor sample was introduced directly into the ion source, the molecular material was decomposed into elements using electron cyclotron resonance plasma and ionized. The following CWAs and stimulants were examined: diisopropyl fluorophosphonate (DFP), 2-chloroethylethylsulfide (2CEES), cyanogen chloride (CNCl), and hydrogen cyanide (HCN). The type of chemical warfare agents, specifically, whether it was a nerve agent, blister agent, blood agent, or choking agent, could be determined by measuring the quantities of the monatomic ions or CN + using mass spectrometry. It was possible to detect gaseous CWAs that could not be detected by a conventional mass spectrometer. The distribution of electron temperature in the plasma could be closely controlled by adjusting the input power of the microwaves used to generate the electron cyclotron resonance plasma, and the target compounds could be detected as molecular ions or fragment ions, enabling identification of the target agents.

  18. Mass Spectrometry Applications for the Identification and Quantitation of Biomarkers Resulting from Human Exposure to Chemical Warfare Agents

    NASA Astrophysics Data System (ADS)

    Smith, J. Richard; Capacio, Benedict R.

    In recent years, a number of analytical methods using biomedical samples such as blood and urine have been developed for the verification of exposure to chemical warfare agents. The majority of methods utilize gas or liquid chromatography in conjunction with mass spectrometry. In a small number of cases of suspected human exposure to chemical warfare agents, biomedical specimens have been made available for testing. This chapter provides an overview of biomarkers that have been verified in human biomedical samples, details of the exposure incidents, the methods utilized for analysis, and the biomarker concentration levels determined in the blood and/or urine.

  19. Analysis of soil samples for chemical warfare agents: Canadian contribution to a multinational round-robin analytical exercise. Memorandum report

    SciTech Connect

    D'Agostino, P.A.; Provost, L.R.; Sawyer, T.W.; Weiss, M.T.

    1990-04-01

    VX and two VX related compounds, diethyl methylphosphonate and bis(2-(diisopropylamino)ethyl) disulfide, were confirmed at the 2 to 40 micrograms/gram level as the principal components in three of four soil samples distributed by Finland as part of a multinational round robin exercise designed to evaluate laboratory methodologies. Several other compounds related to VX, were also identified in extracts of the soil samples. Keywords: Gas chromatography, Canada, Soil samples, Diethyl methylphosphonate, Mass spectrometry, Bis(2-(diisopropylamino)ethyl) disulfide, Bioassay, Defence research establishment suffield(dres), VX, Military chemical agents, International relations, Neuron, Tissue culture, Chemical agent detection.

  20. Biomedical effects of chemical-threat-agent antidote and pretreatment drugs. An abstracted bibliography. Volume 1. Interim report

    SciTech Connect

    Lentz, J.M.; Reams, G.G.; DeJohn, C.A.

    1986-04-01

    The bibliographic abstracts in this report are part of a project to assess biomedical effects of chemical-warfare antidote agents and related pre-treatment drugs. Specific attention is focused on the biomedical effects in the following general areas: vision, auditory, spatial orientation, musculoskeletal, cardipulmonary, cognitive performance, pharmacology, cutaneous stimuli, and cortical effects. In some cases, the bibliography addresses other therapeutic drugs that may be used simultaneously with chemical-warfare antidotes.

  1. Report of National Cancer Institute symposium: comparison of mechanisms of carcinogenesis by radiation and chemical agents. I. Common molecular mechanisms

    SciTech Connect

    Borg, D.C.

    1984-01-01

    Some aspects of molecular mechanisms common to radiation and chemical carcinogenesis are discussed, particularly the DNA damage done by these agents. Emphasis is placed on epidemiological considerations and on dose-response models used in risk assessment to extrapolate from experimental data obtained at high doses to the effects from long-term, low-level exposures. 3 references, 6 figures. (ACR)

  2. REPORT ON THE HOMELAND SECURITY WORKSHOP ON TRANSPORT AND DISPOSAL OF WASTES FROM FACILITIES CONTAMINATED WITH CHEMICAL AND BIOLOGICAL AGENTS

    EPA Science Inventory

    This report summarizes discussions from the "Homeland Security Workshop on Transport and Disposal of Wastes From Facilities Contaminated With Chemical or Biological Agents." The workshop was held on May 28-30, 2003, in Cincinnati, Ohio, and its objectives were to:

    .Documen...

  3. HIGHLY SELECTIVE SENSORS FOR CHEMICAL AND BIOLOGICAL WARFARE AGENTS, INSECTICIDES AND VOCS BASED ON A MOLECULAR SURFACE IMPRINTING TECHNIQUE

    EPA Science Inventory

    Abstract was given as an oral platform presentation at the Pittsburgh Conference, Orlando FL (March 5-9, 2006). Research described is the development of sensors based on molecular surface imprinting. Applications include the monitoring of chemical and biological agents and inse...

  4. Screening methods for chemical warfare agents in environmental samples at the Edgewood area of Aberdeen Proving Ground, Maryland

    SciTech Connect

    Jakubowski, E.M.; Borland, M.M.; Norris, L.; Lattin, F.G.; Wrobel, J.

    1995-06-01

    The U.S. Army Edgewood Research, Development and Engineering Center, the U.S. Army Aberdeen Proving Ground Support Activity, Directorate of Safety, Health and the Environment and SciTech Services Inc., an independent contractor, have developed an approach for screening environmental samples for the presence of chemical warfare agents. Since 1918, the Edgewood area of Aberdeen Proving Ground has been a research and testing ground for toxic agent compounds. Since these materials are considered highly toxic, screening for their presence in environmental samples is necessary for safe shipment to contract laboratories for testing by EPA guidelines. The screening ensures worker safety and maintains U.S. Army standards for transportation of materials potentially contaminated with chemical warfare agents. This paper describes the screening methodology.

  5. Abnormal Development of Tapetum and Microspores Induced by Chemical Hybridization Agent SQ-1 in Wheat

    PubMed Central

    Wang, Shuping; Zhang, Gaisheng; Song, Qilu; Zhang, Yingxin; Li, Zheng; Guo, Jialin; Niu, Na; Ma, Shoucai; Wang, Junwei

    2015-01-01

    Chemical hybridization agent (CHA)-induced male sterility is an important tool in crop heterosis. To demonstrate that CHA-SQ-1-induced male sterility is associated with abnormal tapetal and microspore development, the cytology of CHA-SQ-1-treated plant anthers at various developmental stages was studied by light microscopy, scanning and transmission electron microscopy, in situ terminal deoxynucleotidyl transferasemediated dUTP nick end-labelling (TUNEL) assay and DAPI staining. The results indicated that the SQ-1-treated plants underwent premature tapetal programmed cell death (PCD), which was initiated at the early-uninucleate stage of microspore development and continued until the tapetal cells were completely degraded; the process of microspore development was then blocked. Microspores with low-viability (fluorescein diacetate staining) were aborted. The study suggests that premature tapetal PCD is the main cause of pollen abortion. Furthermore, it determines the starting period and a key factor in CHA-SQ-1-induced male sterility at the cell level, and provides cytological evidence to further study the mechanism between PCD and male sterility. PMID:25803723

  6. Decontamination of chemical and biological warfare (CBW) agents using an atmospheric pressure plasma jet (APPJ)

    SciTech Connect

    Herrmann, H.W.; Henins, I.; Park, J.; Selwyn, G.S.

    1999-05-01

    The atmospheric pressure plasma jet (APPJ) [A. Sch{umlt u}tze {ital et al.}, IEEE Trans. Plasma Sci. {bold 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/O{sub 2}/H{sub 2}O), 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., O{sub 2}{sup {asterisk}}, He{sup {asterisk}}) 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 most plastics, making it highly suitable for decontamination of sensitive equipment and interior spaces. Furthermore, the reactive species in the effluent rapidly degrade into harmless products leaving no lingering residue or harmful by-products. {copyright} {ital 1999 American Institute of Physics.}

  7. Structural, energetic and electrical properties of boron nitride nanotubes interacting with DMMP chemical agent

    NASA Astrophysics Data System (ADS)

    Ganji, M. Darvish; Gholian, M.; Mohammadzadeh, S.

    2014-09-01

    The adsorption of DMMP as an intoxicating chemical warfare agent onto the boron nitride nanotube has been investigated by using density functional theory calculations. Several active sites were considered for both interacting systems and full structural optimization was performed to accurately find the energetically favorable state. It is found that DMMP molecule prefers to be adsorbed strongly on the top site above the B atom of a (5, 0) BNNT with a binding energy of about -103.24 kJ mol-1 and an O-B binding distance of 1.641 Å. We have performed a comparative investigation of BNNTs with different diameters and the results indicate that the DMMP adsorption ability for the side wall of the tubes significantly decreases for higher diameters BNNTs. Furthermore, the adsorption properties of DMMP molecule onto the BNNT have been investigated using the ab initio MD simulation at room temperature. Our result showed that BNNTs facilitates the DMMP detection at ambient conditions for practical applications.

  8. NMIS With Gamma Spectrometry for Attributes of Pu and HEU, Explosives and Chemical Agents

    SciTech Connect

    Mihalczo, J. T.; Mattingly, J. K.; Mullens, J. A.; Neal, J. S.

    2002-05-10

    The concept for the system described herein is an active/passive Nuclear Materials Identification System{sup 2} (NMIS) that incorporates gamma ray spectrometry{sup 3}. This incorporation of gamma ray spectrometry would add existing capability into this system. This Multiple Attribute System can determine a wide variety of attributes for Pu and highly enriched uranium (HEU) of which a selected subset could be chosen. This system can be built using commercial off the shelf (COTS) components. NMIS systems are at All-Russian Scientific Research Institute of Experimental Physics (VNIIEF) and Russian Federal Nuclear Center Institute of Technical Physics, (VNIITF) and measurements with Pu have been performed at VNIIEF and analyzed successfully for mass and thickness of Pu. NMIS systems are being used successfully for HEU at the Y-12 National Security Complex. The use of active gamma ray spectrometry for high explosive HE and chemical agent detection is a well known activation analysis technique, and it is incorporated here. This report describes the system, explains the attribute determination methods for fissile materials, discusses technical issues to be resolved, discusses additional development needs, presents a schedule for building from COTS components, and assembly with existing components, and discusses implementation issues such as lack of need for facility modification and low radiation exposure.

  9. Software algorithms for false alarm reduction in LWIR hyperspectral chemical agent detection

    NASA Astrophysics Data System (ADS)

    Manolakis, D.; Model, J.; Rossacci, M.; Zhang, D.; Ontiveros, E.; Pieper, M.; Seeley, J.; Weitz, D.

    2008-04-01

    The long-wave infrared (LWIR) hyperpectral sensing modality is one that is often used for the problem of detection and identification of chemical warfare agents (CWA) which apply to both military and civilian situations. The inherent nature and complexity of background clutter dictates a need for sophisticated and robust statistical models which are then used in the design of optimum signal processing algorithms that then provide the best exploitation of hyperspectral data to ultimately make decisions on the absence or presence of potentially harmful CWAs. This paper describes the basic elements of an automated signal processing pipeline developed at MIT Lincoln Laboratory. In addition to describing this signal processing architecture in detail, we briefly describe the key signal models that form the foundation of these algorithms as well as some spatial processing techniques used for false alarm mitigation. Finally, we apply this processing pipeline to real data measured by the Telops FIRST hyperspectral (FIRST) sensor to demonstrate its practical utility for the user community.

  10. Investigation of chemical bath deposition of ZnO thin films using six different complexing agents

    NASA Astrophysics Data System (ADS)

    Khallaf, Hani; Chai, Guangyu; Lupan, Oleg; Heinrich, Helge; Park, Sanghoon; Schulte, Alfons; Chow, Lee

    2009-07-01

    Chemical bath deposition of ZnO thin films using six different complexing agents, namely ammonia, hydrazine, ethanolamine, methylamine, triethanolamine and dimethylamine, is investigated. As-grown films were mainly ZnO2 with a band gap around 4.3 eV. Films annealed at 400 °C were identified as ZnO with a band gap around 3.3 eV. X-ray diffraction and micro-Raman spectroscopy revealed that as-grown films consist mainly of cubic zinc peroxide that was transformed into hexagonal ZnO after annealing. Rutherford backscattering spectroscopy (RBS) detected excess oxygen content in ZnO films after annealing. Fourier transform infrared spectroscopy of as-grown films showed a broad absorption band around 3300 cm-1 suggesting that the as-grown films may consist of a mixture of zinc peroxide and zinc hydroxide. X-ray photoelectron spectroscopy multiplex spectra of the O 1s peak were found to be consistent with film stoichiometry revealed by RBS. High-resolution transmission electron micrographs showed small variations of the order of 10 nm in film thickness which corresponds to the average grain size. A carrier density as high as 2.24×1019 cm-3 and a resistivity as low as 6.48 × 10-1 Ω cm were obtained for films annealed at 500 °C in argon ambient.

  11. Measurements of Raman scattering in the middle ultraviolet band from persistent chemical warfare agents

    NASA Astrophysics Data System (ADS)

    Kullander, Fredrik; Landström, Lars; Lundén, Hampus; Mohammed, Abdesalam; Olofsson, Göran; Wästerby, Pär.

    2014-05-01

    The very low Raman scattering cross section and the fluorescence background limit the measuring range of Raman based instruments operating in the visible or infrared band. We are exploring if laser excitation in the middle ultraviolet (UV) band between 200 and 300 nm is useful and advantageous for detection of persistent chemical warfare agents (CWA) on various kinds of surfaces. The UV Raman scattering from tabun, mustard gas, VX and relevant simulants in the form of liquid surface contaminations has been measured using a laboratory experimental setup with a short standoff distance around 1 meter. Droplets having a volume of 1 μl were irradiated with a tunable pulsed laser swept within the middle UV band. A general trend is that the signal strength moves through an optimum when the laser excitation wavelength is swept between 240 and 300 nm. The signal from tabun reaches a maximum around 265 nm, the signal from mustard gas around 275 nm. The Raman signal from VX is comparably weak. Raman imaging by the use of a narrow bandpass UV filter is also demonstrated.

  12. Magnetic hydrophilic-lipophilic balance sorbent for efficient extraction of chemical warfare agents from water samples.

    PubMed

    Singh, Varoon; Purohit, Ajay Kumar; Chinthakindi, Sridhar; Goud D, Raghavender; Tak, Vijay; Pardasani, Deepak; Shrivastava, Anchal Roy; Dubey, Devendra Kumar

    2016-02-19

    Magnetic hydrophilic-lipophilic balance (MHLB) hybrid resin was prepared by precipitation polymerization using N-vinylpyrrolidone (PVP) and divinylbenzene (DVB) as monomers and Fe2O3 nanoparticles as magnetic material. These resins were successfully applied for the extraction of chemical warfare agents (CWAs) and their markers from water samples through magnetic dispersive solid-phase extraction (MDSPE). By varying the ratios of monomers, resin with desired hydrophilic-lipophilic balance was prepared for the extraction of CWAs and related esters of varying polarities. Amongst different composites Fe2O3 nanoparticles coated with 10% PVP+90% DVB exhibited the best recoveries varying between 70.32 and 97.67%. Parameters affecting the extraction efficiencies, such as extraction time, desorption time, nature and volume of desorption solvent, amount of extraction sorbent and the effect of salts on extraction were investigated. Under the optimized conditions, linearity was obtained in the range of 0.5-500 ng mL(-1) with correlation ranging from 0.9911-0.9980. Limits of detection and limits of quantification were 0.5-1.0 and 3.0-5.0 ng mL(-1) respectively with RSDs varying from 4.88-11.32% for markers of CWAs. Finally, the developed MDSPE method was employed for extraction of analytes from water samples of various sources and the OPCW proficiency test samples. PMID:26814366

  13. 75 FR 76460 - Lymphohematopoietic Cancers Induced by Chemicals and Other Agents: Overview and Implications for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-08

    ... in humans, with a primary emphasis on leukemia and leukemia-inducing agents. In addition, the document also focuses on how mechanistic information on human leukemia-inducing agents can inform risk... and radiation in humans, with a primary emphasis on leukemia and leukemia-inducing agents. II. How...

  14. Review of the U.S. Army's health risk assessments for oral exposure to six chemical-warfare agents. Introduction.

    PubMed

    2000-03-01

    The U.S. Army is under a congressional mandate and the Chemical Weapons Convention of January 1993 to destroy its entire stockpile of chemical munitions. In addition to stockpiled munitions, nonstockpile chemical materiel (NSCM) has been identified for destruction. NSCM includes a host of lethal wastes from past disposal efforts, unserviceable munitions, chemically contaminated containers, chemical-production facilities, newly located chemical munitions, known sites containing substantial quantities of buried chemical weapons and wastes, and binary weapons and components. There are eight stockpile sites located in the continental United States and one on an island in the Pacific Ocean, and 82 NSCM locations have been identified. There are concerns, based on storage and past disposal practices, about soil and groundwater contamination at those sites. Six of the most commonly found chemical-warfare agents at stockpile and NSCM sites are the nerve agents GA, GB, GD, and VX and the vesicating (blistering) agents sulfur mustard and lewisite. To ensure that chemical contamination is reduced to safe concentrations at stockpile and NSCM sites before they are used for residential, occupational, or wildlife purposes, the U.S. Army requested that health-based exposure limits for GA, GB, GD, VX, sulfur mustard, and lewisite be developed to protect the public and the environment. Oak Ridge National Laboratory (ORNL) was asked to conduct the health risk assessments and propose chronic oral reference doses (RfDs) and, where appropriate, oral slope factors (SFs) for the six agents. RfDs are toxicological values developed for noncancer effects and used as reference points to limit human oral exposure to potentially hazardous concentrations of chemicals thought to have thresholds for their effects. RfDs are estimates (with uncertainty spanning an order of magnitude or greater) of daily oral chemical exposures that are unlikely to have deleterious effects during a human lifetime. For

  15. COMBINED GAMMA-RAY AND NEUTRON DETECTOR FOR MEASURING THE CHEMICAL COMPOSITION OF AIRLESS PLANETARY BODIES.

    SciTech Connect

    Lawrence, David J. ,; Barraclough, B. L.; Feldman, W. C.; Prettyman, T. H.; Wiens, R. C.

    2001-01-01

    Galactic cosmic rays (GCR) constant1,y itnpinge all planetary bodies and produce characteristic gamma-ray lines and leakage neutrons as reaction products. Together with gamma-ray lines produced by radioactive decay, these nuclear emissions provide a powerful technique for remotely measuring the chemical composition of airless planetary surfaces. While lunar gamma-ray spectroscopy was first demonstrated with Apollo Gamma-Ray measurements, the full value of combined gamma-ray and neutron spectroscopy was shown for the first time with the Lunar Prospector Gamma-Ray (LP-GRS) and Neutron Spectrometers (LP-NS). Any new planetary mission will likely have the requirement that instrument mass and power be kept to a minimum. To satisfy such requirements, we have been designing a GR/NS instrument which combines all the functionality of the LP-GRS and LP-NS for a fraction of the mass and power. Specifically, our design uses a BGO scintillator crystal to measure gamma-rays from 0.5-10 MeV. A borated plastic scintillator and a lithium gliiss scintillator are used to separately measure thermal, epithermal, and fast neutrons as well as serve as an anticoincidence shield for the BGO. All three scintillators are packaged together in a compact phoswich design. Modifications to this design could include a CdZnTe gamma-ray detector for enhanced energy resolution at low energies (0.5-3 MeV). While care needs to be taken to ensure that an adequate count rate is achieved for specific mission designs, previous mission successes demonstrate that a cornbined GR/NS provides essential information about planetary surfaces.

  16. Fabrication of Chemical Sensors, Optical Detectors, and Optical Sources From Metal Nanogap Structures

    NASA Astrophysics Data System (ADS)

    Xing, Wendong

    With the continuing miniaturization of functional devices, nano-structured materials have become of significant scientific and practical interest. In this dissertation, we created a nanogap in silver (Ag) nanowires or electrodeposited nanocrystalline cadmium selenide (nc-CdSe) into FIB cut gold nanogaps and explored their applications for chemical sensors, optical detectors and optical sources. In the first part, the formation of a nanometer-scale chemically responsive junction (CRJ) within a silver nanowire is described. A single Ag nanowire was first prepared on glass using the lithographically patterned nanowire electrodeposition (LPNE) method. Then a 1-5 nm nanogap was created by electromigration and reconnected by applying a voltage ramp across the nanowire resulting in the formation of a resistive (MegaOhms), ohmic CRJ. The resistance changes upon exposure to ammonia (NH3), nitrogen dioxide (NO2) and water vapor have been studied. The proposed mechanism of the enhanced resistance response for a CRJ, supported by Density Function Theory (DFT) calculations is that semiconducting p-type AgxO is formed within the CRJ and the binding of molecules to this AgxO modulates its electrical resistance. In the second part, nc-CdSe was electrodeposited within a sub-50 nm electromigrated gold nanogap, to form a photoconductive metal-semiconductor-metal (M-S-M) nanojunction. The photoconductivity of these nc-CdSe-lled gold nanogaps was characterized by a detectivity of 6.9 × 10 10 Jones and a photosensitivity of 500. These devices also demonstrated a maximum photoconductive gain of ˜45 and response and recovery times below 2 μs, corresponding to a 3 dB bandwidth of at least 175 kHz. In the third part, similar nc-CdSe based M-S-M nanojunctions as in the above photodetector case were demonstrated to be able to emit near-infrared light with a threshold voltage right above the bandgap of CdSe ˜1.7 V. Two different deposition temperatures (20 °C versus 75 °C) were used and

  17. Technical support for recovery phase decision-making in the event of a chemical warfare agent release

    SciTech Connect

    Watson, A.; Kistner, S.; Halbrook, R.

    1995-12-31

    In late 1985, Congress mandated that the U.S. stockpile of lethal unitary chemical agents and munitions be destroyed by the Department of the Army in a manner that provides maximum protection to the environment, the general public and personnel involved in the disposal program (Public Law 99-1, Section 1412, Title 14, Part b). These unitary munitions were last manufactured in the late 1960`s. The stockpiled inventory is estimated to approximate 25,000-30,000 tons, an includes organophosphate ({open_quotes}nerves{close_quotes}) agents such as VX [O-ethylester of S-(diisopropyl aminoethyl) methyl phosphonothiolate, C{sub 11}H{sub 26}NO{sub 2}PS] and vesicant ({open_quotes}blister{close_quotes}) agents such as Hd [sulfur mustard; bis (2-chloroethyl sulfide), C{sub 4}H{sub 8}Cl{sub 2}S]. The method of agent destruction selected by the Department of the Army is combined high-temperature and high-residence time incineration at secured military installations where munitions are currently stockpiled. This program supports the research program to address: the biomonitoring of nerve agent exposure; agent detection limits in foods and milk; and permeation of agents through porous construction materials.

  18. Chemical analysis of bleach and hydroxide-based solutions after decontamination of the chemical warfare agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX).

    PubMed

    Hopkins, F B; Gravett, M R; Self, A J; Wang, M; Chua, Hoe-Chee; Hoe-Chee, C; Lee, H S Nancy; Sim, N Lee Hoi; Jones, J T A; Timperley, C M; Riches, J R

    2014-08-01

    Detailed chemical analysis of solutions used to decontaminate chemical warfare agents can be used to support verification and forensic attribution. Decontamination solutions are amongst the most difficult matrices for chemical analysis because of their corrosive and potentially emulsion-based nature. Consequently, there are relatively few publications that report their detailed chemical analysis. This paper describes the application of modern analytical techniques to the analysis of decontamination solutions following decontamination of the chemical warfare agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX). We confirm the formation of N,N-diisopropylformamide and N,N-diisopropylamine following decontamination of VX with hypochlorite-based solution, whereas they were not detected in extracts of hydroxide-based decontamination solutions by nuclear magnetic resonance (NMR) spectroscopy or gas chromatography-mass spectrometry. We report the electron ionisation and chemical ionisation mass spectroscopic details, retention indices, and NMR spectra of N,N-diisopropylformamide and N,N-diisopropylamine, as well as analytical methods suitable for their analysis and identification in solvent extracts and decontamination residues. PMID:24633585

  19. Laser photoacoustic spectroscopy helps fight terrorism: High sensitivity detection of chemical Warfare Agent and explosives

    NASA Astrophysics Data System (ADS)

    Patel, C. K. N.

    2008-01-01

    Tunable laser photoacoustic spectroscopy is maturing rapidly in its applications to real world problems. One of the burning problems of the current turbulent times is the threat of terrorist acts against civilian population. This threat appears in two distinct forms. The first is the potential release of chemical warfare agents (CWA), such as the nerve agents, in a crowded environment. An example of this is the release of Sarin by Aum Shinrikyo sect in a crowded Tokyo subway in 1995. An example of the second terrorist threat is the ever-present possible suicide bomber in crowded environment such as airports, markets and large buildings. Minimizing the impact of both of these threats requires early detection of the presence of the CWAs and explosives. Photoacoustic spectroscopy is an exquisitely sensitive technique for the detection of trace gaseous species, a property that Pranalytica has extensively exploited in its CO2 laser based commercial instrumentation for the sub-ppb level detection of a number of industrially important gases including ammonia, ethylene, acrolein, sulfur hexafluoride, phosphine, arsine, boron trichloride and boron trifluoride. In this presentation, I will focus, however, on our recent use of broadly tunable single frequency high power room temperature quantum cascade lasers (QCL) for the detection of the CWAs and explosives. Using external grating cavity geometry, we have developed room temperature QCLs that produce continuously tunable single frequency CW power output in excess of 300 mW at wavelengths covering 5 μm to 12 μm. I will present data that show a CWA detection capability at ppb levels with false alarm rates below 1:108. I will also show the capability of detecting a variety of explosives at a ppb level, again with very low false alarm rates. Among the explosives, we have demonstrated the capability of detecting homemade explosives such as triacetone triperoxide and its liquid precursor, acetone which is a common household

  20. Reducing Mortality from Terrorist Releases of Chemical and Biological Agents: I. Filtration for Ventilation Systems in Commercial Building

    SciTech Connect

    Thatcher, Tracy L.; Daisey, Joan M.

    1999-09-01

    There is growing concern about potential terrorist attacks involving releases of chemical and/or biological (CB) agents, such as sarin or anthrax, in and around buildings. For an external release, the CB agent can enter the building through the air intakes of a building's mechanical ventilation system and by infiltration through the building envelope. For an interior release in a single room, the mechanical ventilation system, which often recirculates some fraction of the air within a building, may distribute the released CB agent throughout the building. For both cases, installing building systems that remove chemical and biological agents may be the most effective way to protect building occupants. Filtration systems installed in the heating, ventilating and air-conditioning (HVAC) systems of buildings can significantly reduce exposures of building occupants in the event of a release, whether the release is outdoors or indoors. Reduced exposures can reduce the number of deaths from a terrorist attack. The purpose of this report is to provide information and examples of the design of filtration systems to help building engineers retrofit HVAC systems. The report also provides background information on the physical nature of CB agents and brief overviews of the basic principles of particle and vapor filtration.

  1. Disposal of chemical agents and munitions stored at Pine Bluff Arsenal, Pine Bluff, Arkansas. Final phase 1, Environmental report

    SciTech Connect

    Ensminger, J.T.; Hillsman, E.L.; Johnson, R.D.; Morrisey, J.A.; Staub, W.P.; Boston, C.R.; Hunsaker, D.B.; Leibsch, E.; Rickert, L.W.; Tolbert, V.R.; Zimmerman, G.P.

    1991-09-01

    The Pine Bluff Arsenal (PBA) near Pine Bluff, Arkansas, is one of eight continental United States (CONUS) Army installations where lethal unitary chemical agents and munitions are stored and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at PBA consists of approximately 12%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts). The purpose of this report is to examine the proposed implementation of on-site disposal at PBA in light of more recent and more detailed data than those on which the FPEIS is based. New population data were used to compute fatalities using the same computation methods and values for all other parameters as in the FPEIS. Results indicate that all alternatives are indistinguishable when the potential health impacts to the PBA community are considered. However, risks from on-site disposal are in all cases equal to or less than risks from other alternatives. Furthermore, no unique resources with the potential to prevent or delay implementation of on-site disposal at PBA have been identified.

  2. [Measurement of mutagenesis to study the effects of chemical agents]. Final report, August 1, 1993--July 31, 1994

    SciTech Connect

    Puck, T.T.

    1994-12-31

    This is the final report of a study conducted at the Eleanor Roosevelt Institute for Cancer Research, Inc. This study looked at mutagenesis as a measurement of the effects of chemical agents. Topics discussed in this report include: development of a new theory for the role of lipids and lipoproteins in the interactions of macromolecules; the action of caffeine in synergizing mutagenesis of agents like ionizing radiation by inhibition of cellular repair processes which was incorporated into a rapid procedure for detection of mutagenicity with high sensitivity; quantitative theoretical analysis of the mutagenesis process in cells exposed to physical and chemical mutagenic agents; theoretical analysis was developed leading to the conclusion that the visible chromosomal lesions described will also include a significant proportion of point mutations; application of this methodology for meaningful measurement of mutagenesis to study the effects of chemical agents was begun; and investigation of the cell cytoskeleton`s effect of genome exposure operating in the course of the differentiation process.

  3. Multifunctional ultra-high vacuum apparatus for studies of the interactions of chemical warfare agents on complex surfaces

    NASA Astrophysics Data System (ADS)

    Wilmsmeyer, Amanda R.; Gordon, Wesley O.; Davis, Erin Durke; Mantooth, Brent A.; Lalain, Teri A.; Morris, John R.

    2014-01-01

    A fundamental understanding of the surface chemistry of chemical warfare agents is needed to fully predict the interaction of these toxic molecules with militarily relevant materials, catalysts, and environmental surfaces. For example, rules for predicting the surface chemistry of agents can be applied to the creation of next generation decontaminants, reactive coatings, and protective materials for the warfighter. Here, we describe a multifunctional ultra-high vacuum instrument for conducting comprehensive studies of the adsorption, desorption, and surface chemistry of chemical warfare agents on model and militarily relevant surfaces. The system applies reflection-absorption infrared spectroscopy, x-ray photoelectron spectroscopy, and mass spectrometry to study adsorption and surface reactions of chemical warfare agents. Several novel components have been developed to address the unique safety and sample exposure challenges that accompany the research of these toxic, often very low vapor pressure, compounds. While results of vacuum-based surface science techniques may not necessarily translate directly to environmental processes, learning about the fundamental chemistry will begin to inform scientists about the critical aspects that impact real-world applications.

  4. Multifunctional ultra-high vacuum apparatus for studies of the interactions of chemical warfare agents on complex surfaces

    SciTech Connect

    Wilmsmeyer, Amanda R.; Morris, John R.; Gordon, Wesley O.; Mantooth, Brent A.; Lalain, Teri A.; Davis, Erin Durke

    2014-01-15

    A fundamental understanding of the surface chemistry of chemical warfare agents is needed to fully predict the interaction of these toxic molecules with militarily relevant materials, catalysts, and environmental surfaces. For example, rules for predicting the surface chemistry of agents can be applied to the creation of next generation decontaminants, reactive coatings, and protective materials for the warfighter. Here, we describe a multifunctional ultra-high vacuum instrument for conducting comprehensive studies of the adsorption, desorption, and surface chemistry of chemical warfare agents on model and militarily relevant surfaces. The system applies reflection-absorption infrared spectroscopy, x-ray photoelectron spectroscopy, and mass spectrometry to study adsorption and surface reactions of chemical warfare agents. Several novel components have been developed to address the unique safety and sample exposure challenges that accompany the research of these toxic, often very low vapor pressure, compounds. While results of vacuum-based surface science techniques may not necessarily translate directly to environmental processes, learning about the fundamental chemistry will begin to inform scientists about the critical aspects that impact real-world applications.

  5. Static SIMS and MS2 Characterization of the Chemical Warfare Agent HD on Soil Particle Surfaces

    SciTech Connect

    Gresham, Garold Linn; Groenewold, Gary Steven; Appelhans, Anthony David; Olson, John Eric; Benson, Michael Timothy; Jeffery, M. T.; Rowland, B.; Weibe, M. A.

    2001-07-01

    Detection of the blister agent HD [bis(2-chloroethyl)sulfide] or distilled mustard directly on the surface of soil particles using ion trap secondary ion mass spectrometry in the static mode is demonstrated. HD by its very nature is adsorptive; this attribute makes detection of surface adsorbed HD by gas-phase approaches difficult, but renders the compound amenable to surface detection. Two different ion trap (IT) mass spectrometers, modified to perform secondary ionization mass spectrometry using a ReO4- primary ion beam, were employed in the present study. Sputtered ions were trapped in the gas phase in the IT, where they could be scanned out (MS1), or isolated and fragmented (MS2). The intact HD molecular ion was not observed, however an abundant ion corresponding to [HD - Cl]+ was formed, as were lower mass fragment ions, and ions derived from the chemical background. Ab initio calculations were used to propose structures of the fragment ions. At 0.5 monolayers surface coverage, [HD - Cl]+ and lower mass HD fragment ions were significantly more abundant than the background. At lower concentrations, however, the HD secondary ion signal became masked by the background. Sensitivity and selectivity were significantly improved in the MS2 mode of operation. MS2 of [HD - Cl]+ resulted in production of analytically diagnostic C2H4SH+ and other S- and Cl-bearing fragment ions. HD was detected at 0.07 monolayers using the MS2 approach, which corresponds to 108 ppm on a mass/mass basis.

  6. Preliminary screening of alternative technologies to incineration for treatment of chemical-agent-contaminated soil, Rocky Mountain Arsenal

    SciTech Connect

    Shem, L.M.; Rosenblatt, D.H.; Smits, M.P.; Wilkey, P.L.; Ballou, S.W.

    1995-12-01

    In support of the U.S. Army`s efforts to determine the best technologies for remediation of soils, water, and structures contaminated with pesticides and chemical agents, Argonne National Laboratory has reviewed technologies for treating soils contaminated with mustard, lewisite, sarin, o-ethyl s-(2- (diisopropylamino)ethyl)methyl-phosphonothioate (VX), and their breakdown products. This report focuses on assessing alternatives to incineration for dealing with these contaminants. For each technology, a brief description is provided, its suitability and constraints on its use are identified, and its overall applicability for treating the agents of concern is summarized. Technologies that merit further investigation are identified.

  7. Detection and quantification of chemical warfare agent precursors and surrogates by selected ion flow tube mass spectrometry.

    PubMed

    Francis, Gregory J; Milligan, Daniel B; McEwan, Murray J

    2009-11-01

    The rate coefficients and branching ratios of 15 chemical warfare agent precursor and surrogate compounds reacting with H(3)O(+), NO(+), and O(2)(+) have been measured in the laboratory using the selected ion flow tube (SIFT) technique. Measurement of the relevant kinetic parameters for these agents has enabled quantitative monitoring using the SIFT-MS analytical technique. Thirteen of the 15 compounds studied were found to have real-time detection limits in the parts-per-trillion-by-volume concentration range when measured on a standard commercial Voice100 instrument, with specific compounds having detection limits below 100 parts-per-trillion-by-volume. PMID:19788274

  8. The presentation and management of victims of chemical and biological agents: a survey of knowledge of UK clinicians.

    PubMed

    Wimbush, Stephen; Davies, Gareth; Lockey, David

    2003-09-01

    A survey was conducted among acute specialty clinicians in four centres in the UK to determine their levels of knowledge of the presentation and subsequent management of victims following deliberate release of chemical or biological agents. This revealed significant gaps in knowledge and training. Of the 102 respondents, more than half did not understand the decontamination process. More than a third were unsure of the presenting features of nerve agent release. Only a minority knew the recommended treatment and only one in five have participated in relevant exercises. PMID:12969606

  9. Time-resolved Fourier transform infrared spectroscopy of chemical reactions in solution using a focal plane array detector.

    PubMed

    Kaun, N; Vellekoop, M J; Lendl, B

    2006-11-01

    A Fourier transform infrared (FT-IR) microscope equipped with a single as well as a 64 x 64 element focal plane array MCT detector was used to measure chemical reaction taking place in a microstructured flow cell designed for time-resolved FT-IR spectroscopy. The flow cell allows transmission measurements through aqueous solutions and incorporates a microstructured mixing unit. This unit achieves lamination of the two input streams with a cross-section of 300 x 5 microm each, resulting in fast diffusion-controlled mixing of the two input streams. Microscopic measurement at defined positions along the outlet channel allows time-resolved information of the reaction taking place in the flow cell to be obtained. In this paper we show experimental results on the model reaction between formaldehyde and sulfite. Using the single-point MCT detector, high-quality FT-IR spectra could be obtained from a spot size of 80 x 200 microm whereas the FPA detector allowed recording light from an area of 260 x 260 microm focused on its 64 x 64 detector elements. Therefore, more closely spaced features could be discerned at the expense of a significantly lower signal-to-noise (S/N) ratio per spectrum. Multivariate curve resolution-alternating least squares was used to extract concentration profiles of the reacting species along the outlet channel axis. PMID:17132444

  10. Detection and classification characteristics of arrays of carbon black/organic polymer composite chemiresistive vapor detectors for the nerve agent simulants dimethylmethylphosphonate and diisopropylmethylphosponate.

    PubMed

    Hopkins, A R; Lewis, N S

    2001-03-01

    Arrays of conducting polymer composite vapor detectors have been evaluated for performance in the presence of the nerve agent simulants dimethylmethylphosphonate (DMMP) and diisopropylmethylphosponate (DIMP). Limits of detection for DMMP on unoptimized carbon black/ organic polymer composite vapor detectors in laboratory air were estimated to be 0.047-0.24 mg m(-3). These values are lower than the EC50 value (where EC50 is the airborne concentration sufficient to induce severe effects in 50% of those exposed for 30 min) for the nerve agents sarin (methylphosphonofluoridic acid, 1-methylethyl ester) and soman (methylphosphonofluoridic acid, 1,2,2-trimethylpropyl ester), which has been established as approximately 0.8 mg m(-3). Arrays of these vapor detectors were easily able to resolve signatures due to exposures to DMMP from those due to DIMP or due to a variety of other test analytes (including water, methanol, benzene, toluene, diesel fuel, lighter fluid, vinegar, and tetrahydrofuran) in a laboratory air background. In addition, DMMP at 27 mg m(-3) could be detected and differentiated from the signatures of the other test analytes in the presence of backgrounds of potential interferences, including water, methanol, benzene, toluene, diesel fuel, lighter fluid, vinegar, and tetrahydrofuran, even when these interferents were present in much higher concentrations than that of the DMMP or DIMP being detected. PMID:11289432

  11. Detection and classification characteristics of arrays of carbon black/organic polymer composite chemiresistive vapor detectors for the nerve agent simulants Dimethylmethylphosphonate and Diisopropy

    NASA Astrophysics Data System (ADS)

    Hopkins, Alan R.; Lewis, Nathan S.

    2002-06-01

    Arrays of conducting polymer composite vapor detectors have been evaluated for performance in the presence of the nerve agent simulants dimethylmethylphosphonate (DMMP) and diisopropylmethylphosponate (DIMP). Limits of detection for DMMP on unoptimized carbon black-organic polymer composite vapor detectors in laboratory air were estimated to be 0.047-0.24 mg m-3. These values are lower than the EC50 value for the nerve agents sarin (methylphosphonofluoridic acid, (1-methylethyl) ester) and soman, which have been established as equals 0.8 mg m-3. Arrays of these vapor detectors were easily able to resolve signatures due to exposures to DMMP from those due to DIMP or due to a variety of other test analytes in a laboratory air background. In addition, DMMP at 27 mg m-3 could be detected and differentiated from the signatures of the other test analytes in the presence of backgrounds of potential interferents in the background ambient, including water, methanol, benzene, toluene, diesel fuel, lighter fluid, vinegar and tetrahydrofuran, even when these interferents were present in much higher concentrations than that of the DMMP or DIMP being detected.

  12. The sources, fate, and toxicity of chemical warfare agent degradation products.

    PubMed Central

    Munro, N B; Talmage, S S; Griffin, G D; Waters, L C; Watson, A P; King, J F; Hauschild, V

    1999-01-01

    We include in this review an assessment of the formation, environmental fate, and mammalian and ecotoxicity of CW agent degradation products relevant to environmental and occupational health. These parent CW agents include several vesicants: sulfur mustards [undistilled sulfur mustard (H), sulfur mustard (HD), and an HD/agent T mixture (HT)]; nitrogen mustards [ethylbis(2-chloroethyl)amine (HN1), methylbis(2-chloroethyl)amine (HN2), tris(2-chloroethyl)amine (HN3)], and Lewisite; four nerve agents (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX), tabun (GA), sarin (GB), and soman (GD)); and the blood agent cyanogen chloride. The degradation processes considered here include hydrolysis, microbial degradation, oxidation, and photolysis. We also briefly address decontamination but not combustion processes. Because CW agents are generally not considered very persistent, certain degradation products of significant persistence, even those that are not particularly toxic, may indicate previous CW agent presence or that degradation has occurred. Of those products for which there are data on both environmental fate and toxicity, only a few are both environmentally persistent and highly toxic. Major degradation products estimated to be of significant persistence (weeks to years) include thiodiglycol for HD; Lewisite oxide for Lewisite; and ethyl methyl phosphonic acid, methyl phosphonic acid, and possibly S-(2-diisopropylaminoethyl) methylphosphonothioic acid (EA 2192) for VX. Methyl phosphonic acid is also the ultimate hydrolysis product of both GB and GD. The GB product, isopropyl methylphosphonic acid, and a closely related contaminant of GB, diisopropyl methylphosphonate, are also persistent. Of all of these compounds, only Lewisite oxide and EA 2192 possess high mammalian toxicity. Unlike other CW agents, sulfur mustard agents (e.g., HD) are somewhat persistent; therefore, sites or conditions involving potential HD contamination should include an

  13. The sources, fate, and toxicity of chemical warfare agent degradation products.

    PubMed

    Munro, N B; Talmage, S S; Griffin, G D; Waters, L C; Watson, A P; King, J F; Hauschild, V

    1999-12-01

    We include in this review an assessment of the formation, environmental fate, and mammalian and ecotoxicity of CW agent degradation products relevant to environmental and occupational health. These parent CW agents include several vesicants: sulfur mustards [undistilled sulfur mustard (H), sulfur mustard (HD), and an HD/agent T mixture (HT)]; nitrogen mustards [ethylbis(2-chloroethyl)amine (HN1), methylbis(2-chloroethyl)amine (HN2), tris(2-chloroethyl)amine (HN3)], and Lewisite; four nerve agents (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX), tabun (GA), sarin (GB), and soman (GD)); and the blood agent cyanogen chloride. The degradation processes considered here include hydrolysis, microbial degradation, oxidation, and photolysis. We also briefly address decontamination but not combustion processes. Because CW agents are generally not considered very persistent, certain degradation products of significant persistence, even those that are not particularly toxic, may indicate previous CW agent presence or that degradation has occurred. Of those products for which there are data on both environmental fate and toxicity, only a few are both environmentally persistent and highly toxic. Major degradation products estimated to be of significant persistence (weeks to years) include thiodiglycol for HD; Lewisite oxide for Lewisite; and ethyl methyl phosphonic acid, methyl phosphonic acid, and possibly S-(2-diisopropylaminoethyl) methylphosphonothioic acid (EA 2192) for VX. Methyl phosphonic acid is also the ultimate hydrolysis product of both GB and GD. The GB product, isopropyl methylphosphonic acid, and a closely related contaminant of GB, diisopropyl methylphosphonate, are also persistent. Of all of these compounds, only Lewisite oxide and EA 2192 possess high mammalian toxicity. Unlike other CW agents, sulfur mustard agents (e.g., HD) are somewhat persistent; therefore, sites or conditions involving potential HD contamination should include an

  14. Surface with two paint strips for detection and warning of chemical warfare and radiological agents

    SciTech Connect

    Farmer, Joseph C.

    2013-04-02

    A system for warning of corrosion, chemical, or radiological substances. The system comprises painting a surface with a paint or coating that includes an indicator material and monitoring the surface for indications of the corrosion, chemical, or radiological substances.

  15. Nucleophilic Polymers and Gels in Hydrolytic Degradation of Chemical Warfare Agents.

    PubMed

    Bromberg, Lev; Creasy, William R; McGarvey, David J; Wilusz, Eugene; Hatton, T Alan

    2015-10-01

    Water- and solvent-soluble polymeric materials based on polyalkylamines modified with nucleophilic groups are introduced as catalysts of chemical warfare agent (CWA) hydrolysis. A comparative study conducted at constant pH and based on the criteria of the synthetic route simplicity, aqueous solubility, and rate of hydrolysis of CWA mimic, diisopropylfluorophosphate (DFP), indicated that 4-aminopyridine-substituted polyallylamine (PAAm-APy) and polyvinylamine substituted with 4-aminopyridine (PVAm-APy) were advantageous over 4-pyridinealdoxime-modified PVAm and PAAm, poly(butadiene-co-pyrrolidinopyridine), and PAAm modified with bipyridine and its complex with Cu(II). The synthesis of PVAm-APy and PAAm-APy involved generation of a betaine derivative of acrylamide and its covalent attachment onto the polyalkylamine chain followed by basic hydrolysis. Hydrogel particles of PAAm-APy and PVAm-APy cross-linked by epichlorohydrin exhibited pH-dependent swelling and ionization patterns that affected the rate constants of DFP nucleophilic hydrolysis. Deprotonation of the aminopyridine and amine groups increased the rates of the nucleophilic hydrolysis. The second-order rate of nucleophilic hydrolysis was 5.5- to 10-fold higher with the nucleophile-modified gels compared to those obtained by cross-linking of unmodified PAAm, throughout the pH range. Testing of VX and soman (GD) was conducted in 2.5-3.7 wt % PVAm-APy suspensions or gels swollen in water or DMSO/water mixtures. The half-lives of GD in aqueous PVAm-APy were 12 and 770 min at pH 8.5 and 5, respectively. Addition of VX into 3.5-3.7 wt % suspensions of PVAm-APy in DMSO-d6 and D2O at initial VX concentration of 0.2 vol % resulted in 100% VX degradation in less than 20 min. The unmodified PVAm and PAAm were 2 orders of magnitude less active than PVAm-APy and PAAm-APy, with VX half-lives in the range of 24 h. Furthermore, the PVAm-APy and PAAm-APy gels facilitated the dehydrochlorination reaction of sulfur mustard

  16. A QUANTUM MECHANICAL STUDY OF STRUCTURAL AND ELECTRONIC DILUTION EFFECTS IN PARAMAGNETIC CHEMICAL EXCHANGE SATURATION TRANSFER AGENTS

    PubMed Central

    Miller, Whelton A.; Moore, Preston B.

    2014-01-01

    We present a computational study of the effect of chemical modifications of the meta and para substituents in the coordinating pendant arm of a modified 1,4,7,10-tetraazacyclododecane-N, N’, N″, N‴-tetraamide (DOTAM) ligand on the Chemical Exchange Saturation Transfer (CEST) signal. Magnetic Resonance Imaging (MRI) is currently one of the most widely used techniques available. MRI has led to a new class of pharmaceuticals termed “imagining” or “contrast” agents. These agents usually work by incorporating lanthanide metals such as Gadolinium (Gd) and Europium (Eu). This allows the contrast agents to take advantage of the paramagnetic properties of the metals, which in turn enhances the signal detectable by MRI. The effect of simple electron-withdrawing (e.g., nitro) and electron-donating (e.g., methyl) substituents chemically attached to a modified chelate arm (pendant arm) is quantified by charge transfer interactions in the coordinated water-chelate system computed from quantum mechanics. This study attempts to reveal the origin of the substituent effect on the CEST signal and the electronic structure of the complex. We find that the extent of Charge Transfer (CT) depends on orbital orientations and overlaps. However, CT interactions occur simultaneously from all arms, which causes a dilution effect with respect to the pendant arm. PMID:25485283

  17. Effect of various chemical agents used in gingival retraction systems on smear layer: Scanning electron microscope study

    PubMed Central

    Lahoti, Krishna Shivraj

    2016-01-01

    Background: Chemical agents used for gingival retraction affects the smear layer. Aim: To determine the effect of three different chemical agents used for gingival retraction systems on smear layer. Materials and Methods: Four human premolars were prepared using air-rotor with air-water spray to receive full crown restoration. Three of them were treated with 21.3% aluminum chloride for 10 min, 0.05% oxymetazoline hydrochloride for 10 min, and expasyl for 2 min, respectively. One sample was left untreated. Then, the tooth specimens were rinsed with tap water to remove any residue of test materials. All the samples (treated and untreated) were processed by scanning electron microscope (SEM). Processed samples were examined under SEM at ×2400 to evaluate the effect of chemical agents on smear layer. Results: SEM examination revealed that 0.05% oxymetazoline hydrochloride for 10 min produced no alteration to smear layer followed by minimum alteration by expasyl for 2 min and complete removal of smear layer with etching of dentin with 21.3% aluminum chloride for 10 min. Conclusion: 0.05% oxymetazoline hydrochloride and expasyl are kind to smear layer. PMID:27041896

  18. How Do I Know? A Guide to the Selection of Personal Protective Equipment for Use in Responding to A Release of Chemical Warfare Agents

    SciTech Connect

    Foust, C.B.

    1999-05-01

    An incident involving chemical warfare agents requires a unique hazardous materials (HAZMAT) response. As with an HAZMAT event, federal regulations prescribe that responders must be protected from exposure to the chemical agents. But unlike other HAZMAT events, special considerations govern selection of personal protective equipment (PPE). PPE includes all clothing, respirators and monitoring devices used to respond to a chemical release. PPE can differ depending on whether responders are military or civilian personnel.

  19. Polymers as directing agents for motions of chemical and biological species

    NASA Astrophysics Data System (ADS)

    Tanyeri, Nihan Yonet

    This thesis involves descriptions of solid surface modifications with various polymeric materials which were used as a guiding agent for motion of chemical and biological species. Quasi-two dimensional poly(oligoethylene glycol) acrylate polymer brush based molecular conduits have been designed with the goal of regulating and controlling the diffusive transport of molecular, e.g. organic dyes, and ionic species, e.g. AuCl4-, and Cu2+ ions, along predefined 2-D pathways. The transport of these chemical species has been examined by both fluorescence and dark field microscopy. The polymer brushes were formed through microcontact printing of an initiator, followed by surface-initiated Atom Transfer Radical Polymerization (SI-ATRP). SI-ATRP enables both 2-D patterning with a resolution of about 1 micrometer, and control over the resultant polymer brush thickness (which was varied from 10-100 nm). A hydrophilic poly(oligoethylene glycol) acrylate brushe was selected because of its potential to dissolve a wide range of hydrophilic species. The transport of fluorescent species can be directly followed. A non-lithographic fabrication method was developed for mufluidic devices used in the diffusion studies. Singular channel mufluidic device was utilized to study the directed organic dye diffusion. The AuCl4-, and Cu 2+ ion transport was studied by designing molecular devices with two mufluidic channels. We have demonstrated that the various species of interest diffuse much more rapidly along the predefined pathway than along the bare (polymer brush free) regions of the substrate, demonstrating that diffusive conduits for molecular transport can indeed be formed. The protein resistance of poly(N-isopropylacrylamide) (PNIPAM) brushes grafted from silicon wafers was investigated as a function of the chain molecular weight, grafting density, and temperature. Above the lower critical solution temperature (LCST) of 32°C, the collapse of the water swollen chains, determined by

  20. Crystal Structures of Human Carboxylesterase 1 in Covalent Complexes with the Chemical Warfare Agents Soman and Tabun†,‡

    PubMed Central

    Fleming, Christopher D.; Edwards, Carol C.; Kirby, Stephen D.; Maxwell, Donald M.; Potter, Philip M.; Cerasoli, Douglas M.; Redinbo, Matthew R.

    2008-01-01

    The organophosphorus nerve agents sarin, soman, tabun, and VX exert their toxic effects by inhibiting the action of human acetylcholinesterase, a member of the serine hydrolase superfamily of enzymes. The current treatments for nerve agent exposure must be administered quickly to be effective and they often do not eliminate long-term toxic side effects associated with organophosphate poisoning. Thus, there is significant need for effective prophylactic methods to protect at-risk personnel from nerve agent exposure, and protein-based approaches have emerged as promising candidates. We present the 2.7 Å resolution crystal structures of the serine hydrolase human carboxylesterase 1 (hCE1), a broad-spectrum drug metabolism enzyme, in covalent acyl-enzyme intermediate complexes with the chemical weapons soman and tabun. The structures reveal that hCE1 binds stereoselectively to these nerve agents; for example, hCE1 appears to react preferentially with the 104-fold more lethal PS stereoisomer of soman relative to the PR form. In addition, structural features of the hCE1 active site indicate that the enzyme may be resistant to dead-end organophosphate aging reactions that permanently inactivate other serine hydrolases. Taken together, these data provide important structural details toward the goal of engineering hCE1 into an organophosphate hydrolase and protein-based therapeutic for nerve agent exposure. PMID:17407327

  1. Hydrogen bond-mediated recognition of the chemical warfare agent soman (GD).

    PubMed

    Sambrook, Mark R; Hiscock, Jennifer R; Cook, Alexandra; Green, A Christopher; Holden, Ian; Vincent, Jack C; Gale, Philip A

    2012-06-01

    NMR titration studies in acetonitrile-d(3)/DMSO-d(6) mixtures demonstrate that diindolylurea-based receptors can form complexes with the organophosphorus nerve agent soman in organic solution. PMID:22546851

  2. Method for warning of radiological and chemical agents using detection paints on a vehicle surface

    DOEpatents

    Farmer, Joseph C.; Brunk, James L.; Day, S. Daniel

    2012-03-27

    A paint that warns of radiological or chemical substances comprising a paint operatively connected to the surface, an indicator material carried by the paint that provides an indication of the radiological or chemical substances, and a thermo-activation material carried by the paint. In one embodiment, a method of warning of radiological or chemical substances comprising the steps of painting a surface with an indicator material, and monitoring the surface for indications of the radiological or chemical substances. In another embodiment, a paint is operatively connected to a vehicle and an indicator material is carried by the paint that provides an indication of the radiological or chemical substances.

  3. Aerial vehicle with paint for detection of radiological and chemical warfare agents

    DOEpatents

    Farmer, Joseph C.; Brunk, James L.; Day, S. Daniel

    2013-04-02

    A paint that warns of radiological or chemical substances comprising a paint operatively connected to the surface, an indicator material carried by the paint that provides an indication of the radiological or chemical substances, and a thermo-activation material carried by the paint. In one embodiment, a method of warning of radiological or chemical substances comprising the steps of painting a surface with an indicator material, and monitoring the surface for indications of the radiological or chemical substances. In another embodiment, a paint is operatively connected to a vehicle and an indicator material is carried by the paint that provides an indication of the radiological or chemical substances.

  4. Role of chelating agent in chemical and fluorescent properties of SnO2 nanoparticles

    NASA Astrophysics Data System (ADS)

    He, Shao-Bo; Wang, Shi-Fa; Ding, Qing-Ping; Yuan, Xiao-Dong; Zheng, Wan-Guo; Xiang, Xia; Li, Zhi-Jie; Zu, Xiao-Tao

    2013-05-01

    A modified Polyacrylamide gel route is applied to synthesize SnO2 nanoparticles. High-quality SnO2 nanoparticles with a uniform size are prepared using different chelating agents. The average particle size of the samples is found to depend on the choice of the chelating agent. The photoluminescence spectrum detected at λex = 230 nm shows a new peak located at 740 nm due to the surface defect level distributed at the nanoparticle boundaries.

  5. Chemical agents for conversion of chrysotile asbestos into non-hazardous materials

    DOEpatents

    Sugama, Toshifumi; Petrakis, L.

    1998-06-09

    A composition and methods are disclosed for converting a chrysotile asbestos-containing material to a non-regulated environmentally benign solid which comprises a fluoro acid decomposing agent capable of dissociating the chrysotile asbestos to non-regulated components, wherein non-regulated components are non-reactive with the environment, and a binding agent which binds the non-regulated components to form an environmentally benign solid. 2 figs.

  6. Chemical agents for conversion of chrysotile asbestos into non-hazardous materials

    DOEpatents

    Sugama, Toshifumi; Petrakis, Leon

    1998-06-09

    A composition and methods for converting a chrysotile asbestos-containing material to a non-regulated environmentally benign solid which comprises a fluoro acid decomposing agent capable of dissociating the chrysotile asbestos to non-regulated components, wherein non-regulated components are non-reactive with the environment, and a binding agent which binds the non-regulated components to form an environmentally benign solid.

  7. Toxins as weapons of mass destruction. A comparison and contrast with biological-warfare and chemical-warfare agents.

    PubMed

    Madsen, J M

    2001-09-01

    Toxins are toxic chemical compounds synthesized in nature by living organisms. Classifiable by molecular weight, source, preferred targets in the body, and mechanism of action, they include the most potent poisons on the planet, although considerations of production, weaponization, delivery, environmental stability, and host factors place practical limits on their use as WMD. The two most important toxin threats on the battlefield or in bioterrorism are probably botulinum toxin (a series of seven serotypes, of which botulinum toxin A is the most toxic for humans) and SEB, an incapacitating toxin. Ricin and the trichothecene mycotoxins, including T-2 mycotoxin, are of lesser concern but are still potential threats. Botulinum toxin is a neurotoxin, ricin and trichothecene mycotoxins are membrane-damaging proteins, and SEB is a superantigen capable of massive nonspecific activation of the immune system. The clinical intoxications resulting from exposure to and absorption (usually by inhalation) of these agents reflect their underlying pathophysiology. Because of the hybrid nature of toxins, they have sometimes been considered CW agents and sometimes BW agents. The current trend seems to be to emphasize their similarities to living organisms and their differences from CW agents, but examination of all three groups relative to a number of factors reveals both similarities and differences between toxins and each of the other two categories of non-nuclear unconventional WMD. The perspective that groups toxins with BW agents is logical and very useful for research and development and for administrative and treaty applications, but for medical education and casualty assessment, there are real advantages in clinician use of assessment techniques that emphasize the physicochemical behavior of these nonliving, nonreplicating, intransmissible chemical poisons. PMID:11577702

  8. Imaging In Vivo Extracellular pH with a Single Paramagnetic Chemical Exchange Saturation Transfer Magnetic Resonance Imaging Contrast Agent

    PubMed Central

    Liu, Guanshu; Li, Yuguo; Sheth, Vipul R.; Pagel, Mark D.

    2016-01-01

    The measurement of extracellular pH (pHe) has potential utility for cancer diagnoses and for assessing the therapeutic effects of pH-dependent therapies. A single magnetic resonance imaging (MRI) contrast agent that is detected through paramagnetic chemical exchange saturation transfer (PARACEST) was designed to measure tumor pHe throughout the range of physiologic pH and with magnetic resonance saturation powers that are not harmful to a mouse model of cancer. The chemical characterization and modeling of the contrast agent Yb3+-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid,10-o-aminoanilide (Yb-DO3A-oAA) suggested that the aryl amine of the agent forms an intramolecular hydrogen bond with a proximal carboxylate ligand, which was essential for generating a practical chemical exchange saturation transfer (CEST) effect from an amine. A ratio of CEST effects from the aryl amine and amide was linearly correlated with pH throughout the physiologic pH range. The pH calibration was used to produce a parametric pH map of a subcutaneous flank tumor on a mouse model of MCF-7 mammary carcinoma. Although refinements in the in vivo CEST MRI methodology may improve the accuracy of pHe measurements, this study demonstrated that the PARACEST contrast agent can be used to generate parametric pH maps of in vivo tumors with saturation power levels that are not harmful to a mouse model of cancer. PMID:22418027

  9. Disposal of chemical agents and munitions stored at Umatilla Depot Activity, Hermiston, Oregon. Final Phase 1 environmental report

    SciTech Connect

    Zimmerman, G.P.; Hillsman, E.L.; Johnson, R.O.; Miller, R.L.; Patton, T.G.; Schoepfle, G.M.; Tolbert, V.R.; Feldman, D.L.; Hunsaker, D.B. Jr.; Kroodsma, R.L.; Morrissey, J.; Rickert, L.W.; Staub, W.P.; West, D.C.

    1993-02-01

    The Umatilla Depot Activity (UMDA) near Hermiston, Oregon, is one of eight US Army installations in the continental United States where lethal unitary chemical agents and munitions are stored, and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at UMDA consists of 11.6%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts), using a method based on five measures of risk for potential human health and ecosystem/environmental effects; the effectiveness and adequacy of emergency preparedness capabilities also played a key role in the FPEIS selection methodology. In some instances, the FPEIS included generic data and assumptions that were developed to allow a consistent comparison of potential impacts among programmatic alternatives and did not include detailed conditions at each of the eight installations. The purpose of this Phase 1 report is to examine the proposed implementation of on-site disposal at UMDA in light of more recent and more detailed data than those included in the FPEIS. Specifically, this Phase 1 report is intended to either confirm or reject the validity of on-site disposal for the UMDA stockpile. Using the same computation methods as in the FPEIS, new population data were used to compute potential fatalities from hypothetical disposal accidents. Results indicate that onsite disposal is clearly preferable to either continued storage at UMDA or transportation of the UMDA stockpile to another depot for disposal.

  10. Report on NCI symposium: comparison of mechanisms of carcinogenesis by radiation and chemical agents. II. Cellular and animal models

    SciTech Connect

    Fry, R.J.M.

    1984-01-01

    The point at which the common final pathway for induction of cancer by chemical carcinogens and ionizing radiation has not been identified. Although common molecular targets are suggested by recent findings about the role of oncogenes, the mechanism by which the deposition of radiation energy and the formation of adducts or other DNA lesions induced by chemicals affects the changes in the relevant targets may be quite different. The damage to DNA that plays no part in the transformation events, but that influences the stability of the genome, and therefore, the probability of subsequent changes that influence tumorigenesis may be more readily induced by some agents than others. Similarly, the degree of cytotoxic effects that disrupt tissue integrity and increase the probability of expression of initiated cells may be dependent on the type of carcinogen. Also, evidence was presented that repair of the initial lesions could be demonstrated after exposure to low-LET radiation but not after exposure to chemical carcinogens.

  11. Research on the interaction of hydrogen-bond acidic polymer sensitive sensor materials with chemical warfare agents simulants by inverse gas chromatography.

    PubMed

    Yang, Liu; Han, Qiang; Cao, Shuya; Huang, Feng; Qin, Molin; Guo, Chenghai; Ding, Mingyu

    2015-01-01

    Hydrogen-bond acidic polymers are important high affinity materials sensitive to organophosphates in the chemical warfare agent sensor detection process. Interactions between the sensor sensitive materials and chemical warfare agent simulants were studied by inverse gas chromatography. Hydrogen bonded acidic polymers, i.e., BSP3, were prepared for micro-packed columns to examine the interaction. DMMP (a nerve gas simulant) and 2-CEES (a blister agent simulant) were used as probes. Chemical and physical parameters such as heats of absorption and Henry constants of the polymers to DMMP and 2-CEES were determined by inverse gas chromatography. Details concerning absorption performance are also discussed in this paper. PMID:26043177

  12. Research on the Interaction of Hydrogen-Bond Acidic Polymer Sensitive Sensor Materials with Chemical Warfare Agents Simulants by Inverse Gas Chromatography

    PubMed Central

    Yang, Liu; Han, Qiang; Cao, Shuya; Huang, Feng; Qin, Molin; Guo, Chenghai; Ding, Mingyu

    2015-01-01

    Hydrogen-bond acidic polymers are important high affinity materials sensitive to organophosphates in the chemical warfare agent sensor detection process. Interactions between the sensor sensitive materials and chemical warfare agent simulants were studied by inverse gas chromatography. Hydrogen bonded acidic polymers, i.e., BSP3, were prepared for micro-packed columns to examine the interaction. DMMP (a nerve gas simulant) and 2-CEES (a blister agent simulant) were used as probes. Chemical and physical parameters such as heats of absorption and Henry constants of the polymers to DMMP and 2-CEES were determined by inverse gas chromatography. Details concerning absorption performance are also discussed in this paper. PMID:26043177

  13. Ram-air sample collection device for a chemical warfare agent sensor

    DOEpatents

    Megerle, Clifford A.; Adkins, Douglas R.; Frye-Mason, Gregory C.

    2002-01-01

    In a surface acoustic wave sensor mounted within a body, the sensor having a surface acoustic wave array detector and a micro-fabricated sample preconcentrator exposed on a surface of the body, an apparatus for collecting air for the sensor, comprising a housing operatively arranged to mount atop the body, the housing including a multi-stage channel having an inlet and an outlet, the channel having a first stage having a first height and width proximate the inlet, a second stage having a second lower height and width proximate the micro-fabricated sample preconcentrator, a third stage having a still lower third height and width proximate the surface acoustic wave array detector, and a fourth stage having a fourth height and width proximate the outlet, where the fourth height and width are substantially the same as the first height and width.

  14. Polynorbornene derived 8-hydroxyquinoline paper strips for ultrasensitive chemical nerve agent surrogate sensing.

    PubMed

    Sarkar, Santu; Shunmugam, Raja

    2014-08-11

    The detection of nerve agent simulants is achieved by the photoinduced electron transfer (PET) mechanism. A "turn-on" fluorescence response upon phosphorylation at 8-hydroxyquinoline of norbornene-based triazolyl functionalized 8-hydroxyquinoline () followed by intramolecular rearrangement provides very intense green emission. The detection limit of polymer () coated paper strips is 25 ppb with instantaneous response. PMID:24948420

  15. Expedient Respiratory and Physical Protection: Does a Wet Towel Work to Prevent Chemical Warfare Agent Vapor Infiltration?

    SciTech Connect

    Sorensen, J.H.

    2002-08-30

    The purpose of this paper is to examine the effectiveness of expedient protection strategies to reduce exposure to vapors from chemical warfare agents. This includes an examination of the physical and the psychological effectiveness of measures such as using a wet towel to seal a door jam against the infiltration of chemicals while sheltering in place or to provide expedient respiratory protection. Respiratory protection for civilians has never been considered a viable option for population protection in the CSEPP. Problems of storage, ability to effectively don respirators, and questionable fit have been primary factors in rejecting this option. Expedient respiratory protection seems to offer little benefits for population protection for chemical agent vapors. Furthermore, using wet towels as a vapor barrier at the bottom of a door should be discouraged. The wetted towel provides no vapor filtration and its effectiveness in infiltration reduction is unknown. Taping the bottom of the door will still likely provide greater infiltration reduction and is recommended as the current method for use in sheltering.

  16. Standoff detection of explosives and chemical agents using broadly tuned external-cavity quantum cascade lasers (EC-QCLs)

    NASA Astrophysics Data System (ADS)

    Takeuchi, Eric B.; Rayner, Timothy; Weida, Miles; Crivello, Salvatore; Day, Timothy

    2007-10-01

    Civilian soft targets such as transportation systems are being targeted by terrorists using IEDs and suicide bombers. Having the capability to remotely detect explosives, precursors and other chemicals would enable these assets to be protected with minimal interruption of the flow of commerce. Mid-IR laser technology offers the potential to detect explosives and other chemicals in real-time and from a safe standoff distance. While many of these agents possess "fingerprint" signatures in the mid-IR (i.e. in the 3-20 micron regime), their effective interrogation by a practical, field-deployable system has been limited by size, complexity, reliability and cost constraints of the base laser technology. Daylight Solutions has addressed these shortcomings by developing compact, portable, broadly tunable mid-IR laser sources based upon external-cavity quantum cascade technology. This technology is now being applied by Daylight in system level architectures for standoff and remote detection of explosives, precursors and chemical agents. Several of these architectures and predicted levels of performance will be presented.

  17. Iron oxide functionalized graphene nano-composite for dispersive solid phase extraction of chemical warfare agents from aqueous samples.

    PubMed

    Chinthakindi, Sridhar; Purohit, Ajay; Singh, Varoon; Tak, Vijay; Goud, D Raghavender; Dubey, D K; Pardasani, Deepak

    2015-05-15

    Present study deals with the preparation and evaluation of graphene based magnetic nano-composite for dispersive solid phase extraction of Chemical Weapons Convention (CWC) relevant chemicals from aqueous samples. Nano-composite, Fe3O4@SiO2-G was synthesized by covalently bonding silica coated Fe3O4 onto the graphene sheets. Nerve agents (NA), Sulfur mustard (SM) and their non-toxic environmental markers were the target analytes. Extraction parameters like amount of sorbent, extraction time and desorption conditions were optimized. Dispersion of 20 milligram of sorbent in 200mL of water sample for 20min. followed by methanol/chloroform extraction produced average to good recoveries (27-94%) of targeted analytes. Recoveries of real agents exhibited great dependency upon sample pH and ionic strength. Sarin produced maximum recovery under mild acidic conditions (56% at pH 5) while VX demanded alkaline media (83% at pH 9). Salts presence in the aqueous samples was found to be advantageous, raising the recoveries to as high as 94% for SM. Excellent limits of detection (LOD) for sulphur mustard and VX (0.11ngmL(-1) and 0.19ngmL(-1) respectively) proved the utility of the developed method for the off-site analysis of CWC relevant chemicals. PMID:25828545

  18. Chemical and biological threat-agent detection using electrophoresis-based lab-on-a-chip devices.

    PubMed

    Borowsky, Joseph; Collins, Greg E

    2007-10-01

    The ability to separate complex mixtures of analytes has made capillary electrophoresis (CE) a powerful analytical tool since its modern configuration was first introduced over 25 years ago. The technique found new utility with its application to the microfluidics based lab-on-a-chip platform (i.e., microchip), which resulted in ever smaller footprints, sample volumes, and analysis times. These features, coupled with the technique's potential for portability, have prompted recent interest in the development of novel analyzers for chemical and biological threat agents. This article will comment on three main areas of microchip CE as applied to the separation and detection of threat agents: detection techniques and their corresponding limits of detection, sampling protocol and preparation time, and system portability. These three areas typify the broad utility of lab-on-a-chip for meeting critical, present-day security, in addition to illustrating areas wherein advances are necessary. PMID:17893797

  19. Dual-Function Metal-Organic Framework as a Versatile Catalyst for Detoxifying Chemical Warfare Agent Simulants.

    PubMed

    Liu, Yangyang; Moon, Su-Young; Hupp, Joseph T; Farha, Omar K

    2015-12-22

    The nanocrystals of a porphyrin-based zirconium(IV) metal-organic framework (MOF) are used as a dual-function catalyst for the simultaneous detoxification of two chemical warfare agent simulants at room temperature. Simulants of nerve agent (such as GD, VX) and mustard gas, dimethyl 4-nitrophenyl phosphate and 2-chloroethyl ethyl sulfide, have been hydrolyzed and oxidized, respectively, to nontoxic products via a pair of pathways catalyzed by the same MOF. Phosphotriesterase-like activity of the Zr6-containing node combined with photoactivity of the porphyrin linker gives rise to a versatile MOF catalyst. In addition, bringing the MOF crystals down to the nanoregime leads to acceleration of the catalysis. PMID:26482030

  20. Evaluation of metal mobility, plant availability and immobilization by chemical agents in a limed-silty soil.

    PubMed

    Mench, M; Vangronsveld, J; Didier, V; Clijsters, H

    1994-01-01

    Metal-contaminated soils in the vicinity of industrial sites become of ever-increasing concern. Diagnostic criteria and ecological technologies for soil remediation should be calibrated for various soil conditions; actually, our knowledge of calcareous soil is poor. Silty soils near smelters at Evin (Pas de Calais, France) have been contaminated by non-ferrous metal fallout and regularly limed using foams. Therefore, the mobility, bioavailability, and potential phytotoxicity of Cd, Pb and Zn, were investigated using single soil extractions (i.e. water, 0.1 n Ca(NO(3))(2), and EDTA pH 7), and vegetation experiments, in parallel with a biological test based on (iso)-enzymes in leaves and roots, before and following soil treatment with chemical agents, i.e. Thomas basic slags (TBS), hydrous manganese oxide (HMO), steel shots (ST) and beringite. No visible toxicity symptoms developed on the above-ground parts of ryegrass, tobacco and bean plants grown in potted soil under controlled environmental conditions. Cd, Zn and Pb uptake resulted in high concentrations in the above-ground plant parts, but the enzyme capacities in leaves and roots, and the peroxidase pattern indicated that these metal concentrations were not phytotoxic for beans as test plants. The addition of chemical agents to the soil did not increase biomass production, but treatment with either HMO, ST or beringite markedly decreased the mobility of Cd, Zn and Pb. These agents were proven to be effective in mitigating the Cd uptake by plants. HMO and ST decreased either Pb or Zn uptake by ryegrass. TBS was effective in lowering Pb uptake by the same species. Beringite decreased Cd uptake by beans. If fallout could be restricted, the metal content of food crops in this area should be lowered by soil treatment. However, the differences in Cd uptake between plant species were not suppressed, regardless of the type of agents applied to the soil. PMID:15091619

  1. Comparative antibacterial activity of silver nanoparticles synthesised by biological and chemical routes with pluronic F68 as a stabilising agent.

    PubMed

    Santos, Carolina Alves Dos; Seckler, Marcelo Martins; Ingle, Avinash P; Rai, Mahendra

    2016-08-01

    The authors report the comparative antibacterial activity of silver nanoparticles synthesised by biological (using Fusarium oxysporum) and chemical routes in the presence and absence of pluronic F68 as a stabilising agent. The production of silver nanoparticles was evidenced by UV-visible spectra, with absorbance at about 420 nm in the case of both biological and chemical synthesis. X-ray diffraction pattern confirmed the presence of face-centred cubic structure (FCC plane). The nanoparticles characterised by transmission and scanning electron microscopy showed spherical silver nanoparticles with size range of 5-40 and 10-70 nm in the case of biologically and chemically synthesised nanoparticles, respectively. Addition of pluronic F68 showed the stabilisation of silver nanoparticles. Antibacterial efficacy of silver nanoparticles demonstrated different inhibitory activity against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. Overall, biologically synthesised silver nanoparticles showed higher activity as compared with chemically synthesised nanoparticles. Silver nanoparticles synthesised in the presence of pluronic F68 by the chemical route exhibited synergism in antibacterial activity as compared with those synthesised without pluronic F68. On the contrary, biogenic silver nanoparticles without pluronic F68 showed higher antibacterial potential. PMID:27463790

  2. Identification of vapor-phase chemical warfare agent simulants and rocket fuels using laser-induced breakdown spectroscopy

    SciTech Connect

    Stearns, Jaime A.; McElman, Sarah E.; Dodd, James A.

    2010-05-01

    Application of laser-induced breakdown spectroscopy (LIBS) to the identification of security threats is a growing area of research. This work presents LIBS spectra of vapor-phase chemical warfare agent simulants and typical rocket fuels. A large dataset of spectra was acquired using a variety of gas mixtures and background pressures and processed using partial least squares analysis. The five compounds studied were identified with a 99% success rate by the best method. The temporal behavior of the emission lines as a function of chamber pressure and gas mixture was also investigated, revealing some interesting trends that merit further study.

  3. Chemical polysialylation of human recombinant butyrylcholinesterase delivers a long-acting bioscavenger for nerve agents in vivo

    PubMed Central

    Ilyushin, Denis G.; Smirnov, Ivan V.; Belogurov, Alexey A.; Dyachenko, Igor A.; Zharmukhamedova, Tatiana Iu.; Novozhilova, Tatjana I.; Bychikhin, Eugene A.; Serebryakova, Marina V.; Kharybin, Oleg N.; Murashev, Arkadii N.; Anikienko, Konstantin A.; Nikolaev, Eugene N.; Ponomarenko, Natalia A.; Genkin, Dmitry D.; Blackburn, G. Michael; Masson, Patrick; Gabibov, Alexander G.

    2013-01-01

    The creation of effective bioscavengers as a pretreatment for exposure to nerve agents is a challenging medical objective. We report a recombinant method using chemical polysialylation to generate bioscavengers stable in the bloodstream. Development of a CHO-based expression system using genes encoding human butyrylcholinesterase and a proline-rich peptide under elongation factor promoter control resulted in self-assembling, active enzyme multimers. Polysialylation gives bioscavengers with enhanced pharmacokinetics which protect mice against 4.2 LD50 of S-(2-(diethylamino)ethyl) O-isobutyl methanephosphonothioate without perturbation of long-term behavior. PMID:23297221

  4. Chemical Surface Washing Agents for Oil Spills: Update State-of-the-Art on Mechanisms of Action and Evaluation of Two Laboratory Effectiveness Tests.

    EPA Science Inventory

    Chemical surface washing agents are formulations designed to help release stranded oil from shoreline substrates.The U.S. Environmental Protection Agency (EPA), in response to the Oil Pollution Act of 1990, Initiated study of these cleaning agents. The project summarized here had...

  5. Laboratory evaluation of a chemical coupling agent to prevent debonding of asphalts from aggregates

    NASA Astrophysics Data System (ADS)

    Divito, J. A.

    1981-08-01

    Debonding of asphalt from mineral aggregates (stripping) was investigated. A silane coupling agent was compared with a well known, commercially available liquid antistrip (amine) in the immersion compression and double punch debonding tests on two Arizona mineral aggregate sources. The silane was used as a mineral aggregate pretreatment while the amine was added to the asphalt. It is indicated that the silane generally performed as well as the liquid antistrip or better.

  6. Rapid response behavior, at room temperature, of a nanofiber-structured TiO2 sensor to selected simulant chemical-warfare agents.

    PubMed

    Ma, Xingfa; Zhu, Tao; Xu, Huizhong; Li, Guang; Zheng, Junbao; Liu, Aiyun; Zhang, Jianqin; Du, Huatai

    2008-02-01

    A chemical prototype sensor was constructed based on nanofiber-structured TiO2 and highly sensitive quartz resonators. The gas-sensing behavior of this new sensor to selected simulant warfare agents was investigated at room temperature. Results showed rapid response and good reversibility of this sensor when used with high-purity nitrogen. This provides a simple approach to preparation of materials needed as chemical sensors for selected organic volatiles or warfare agents. PMID:18094961

  7. Implications and mitigation of model mismatch and covariance contamination for hyperspectral chemical agent detection

    NASA Astrophysics Data System (ADS)

    Niu, Sidi; Golowich, Steven E.; Ingle, Vinay K.; Manolakis, Dimitris G.

    2013-02-01

    Most chemical gas detection algorithms for long-wave infrared hyperspectral images assume a gas with a perfectly known spectral signature. In practice, the chemical signature is either imperfectly measured and/or exhibits spectral variability due to temperature variations and Beers law. The performance of these detection algorithms degrades further as a result of unavoidable contamination of the background covariance by the plume signal. The objective of this work is to explore robust matched filters that take the uncertainty and/or variability of the target signatures into account and mitigate performance loss resulting from different factors. We introduce various techniques that control the selectivity of the matched filter and we evaluate their performance in standoff LWIR hyperspectral chemical gas detection applications.

  8. Fiber optic detector and method for using same for detecting chemical species

    DOEpatents

    Baylor, Lewis C.; Buchanan, Bruce R.

    1995-01-01

    An optical sensing device for uranyl and other substances, a method for making an optical sensing device and a method for chemically binding uranyl and other indicators to glass, quartz, cellulose and similar substrates. The indicator, such as arsenazo III, is immobilized on the substrate using a chemical binding process. The immobilized arsenazo III causes uranyl from a fluid sample to bind irreversibly to the substrate at its active sites, thus causing absorption of a portion of light transmitted through the substrate. Determination of the amount of light absorbed, using conventional means, yields the concentration of uranyl present in the sample fluid. The binding of uranyl on the substrate can be reversed by subsequent exposure of the substrate to a solution of 2,6-pyridinedicarboxylic acid. The chemical binding process is suitable for similarly binding other indicators, such as bromocresol green.

  9. Development of electrochemical sensors for trace detection of explosives and for the detection of chemical warfare agents

    NASA Astrophysics Data System (ADS)

    Berger, T.; Ziegler, H.; Krausa, Michael

    2000-08-01

    A huge number of chemical sensors are based on electrochemical measurement methods. Particularly amperometric sensorsystems are employed for the fast detection of pollutants in industry and environment as well as for analytic systems in the medical diagnosis. The large number of different applications of electrochemical sensors is based on the high sensitivity of electrochemical methods and on the wide of possibilities to enhance the selectivity by variation of electrochemical and chemical parameters. Besides this, electrochemical sensorsystems are frequently simple to operate, transportable and cheap. Up to now the electrochemical method of cyclic voltammetry is used only seldom for sensors. Clearly the efficiency of cyclic voltammetry can be seen at the sensorsystem for the detection of nitro- and aminotoluenes in solids and waters as presented here. The potentiodynamic sensors system can be employed for the fast and easy risk estimation of contaminated areas. Because of the high sensitivity of electrochemical methods the detection of chemical substances with a low vapor pressure is possible also. The vapor pressure of TNT at room temperature is 7 ppb for instances. With a special electrochemical set-up we were able to measure TNT approximately 10 cm above a TNT-sample. In addition we were able to estimate TNT in the gaseous phase approximately 10 cm above a real plastic mine. Therefore it seems to be possible to develop an electrochemical mien detection. Moreover, we present that the electrochemical detection of RDX, HMX and chemical warfare agents is also possible.

  10. Optical properties and surface structure comparison of tooth whitening using four laser systems and chemical action agents

    NASA Astrophysics Data System (ADS)

    Dostalova, Tatjana; Jelinkova, Helena; Koranda, Pavel; Nemec, Michal; Sulc, Jan; Housova, Devana; Miyagi, Mitsunobu; Kokta, Milan R.

    2003-06-01

    The purpose of the study is to evaluate the effect of various laser techniques for bleaching teeth in office vital whitening. Hydrogen peroxide (30% concentration) and carbamide peroxide (10% solution) were used for chemical activation of bleaching process. Extracted non-carcious upper central incisors were exposed to laser radiation. Four different laser systems (Nd:YAG laser SHG, wavelength 0.53 μm, CTE:YAG laser, wavelength 2.7 μm, Nd:YAG laser, wavelength 1.06 μm, and alexandrite laser, wavelength 0.75 μm) were applied to accelerate the speed of the process. The end of chemical exposition was verified by the change of bleaching agent color. The color change was determined by stereomicroscope (Nikon SMZ 2T, Japan), the quality of surface structure was checked by scanning electron microscope Joel, Japan). The speed of bleaching rnaged from 630 s (chemical methods only) to 250-340 s (chemicals + alexandrite laser radiation). The Alexandrite laser application was considered an elective process to decrease the time of bleaching without modifying the surface.

  11. The effect of different chemical agents on human enamel: an atomic force and scanning electron microscopy study

    NASA Astrophysics Data System (ADS)

    Rominu, Roxana O.; Rominu, Mihai; Negrutiu, Meda Lavinia; Sinescu, Cosmin; Pop, Daniela; Petrescu, Emanuela

    2010-12-01

    PURPOSE: The goal of our study was to investigate the changes in enamel surface roughess induced by the application of different chemical substances by atomic force microscopy and scanning electron microscopy. METHOD: Five sound human first upper premolar teeth were chosen for the study. The buccal surface of each tooth was treated with a different chemical agent as follows: Sample 1 - 38% phosphoric acid etching (30s) , sample 2 - no surface treatment (control sample), 3 - bleaching with 37.5 % hydrogen peroxide (according to the manufacturer's instructions), 4 - conditioning with a self-etching primer (15 s), 5 - 9.6 % hydrofluoric acid etching (30s). All samples were investigated by atomic force microscopy in a non-contact mode and by scanning electron microscopy. Several images were obtained for each sample, showing evident differences regarding enamel surface morphology. The mean surface roughness and the mean square roughness were calculated and compared. RESULTS: All chemical substances led to an increased surface roughness. Phosphoric acid led to the highest roughness while the control sample showed the lowest. Hydrofluoric acid also led to an increase in surface roughness but its effects have yet to be investigated due to its potential toxicity. CONCLUSIONS: By treating the human enamel with the above mentioned chemical compounds a negative microretentive surface is obtained, with a morphology depending on the applied substance.

  12. Enzymatic neutralization of the chemical warfare agent VX: evolution of phosphotriesterase for phosphorothiolate hydrolysis.

    PubMed

    Bigley, Andrew N; Xu, Chengfu; Henderson, Terry J; Harvey, Steven P; Raushel, Frank M

    2013-07-17

    The V-type nerve agents (VX and VR) are among the most toxic substances known. The high toxicity and environmental persistence of VX make the development of novel decontamination methods particularly important. The enzyme phosphotriesterase (PTE) is capable of hydrolyzing VX but with an enzymatic efficiency more than 5 orders of magnitude lower than with its best substrate, paraoxon. PTE has previously proven amenable to directed evolution for the improvement of catalytic activity against selected compounds through the manipulation of active-site residues. Here, a series of sequential two-site mutational libraries encompassing 12 active-site residues of PTE was created. The libraries were screened for catalytic activity against a new VX analogue, DEVX, which contains the same thiolate leaving group of VX coupled to a diethoxyphosphate core rather than the ethoxymethylphosphonate core of VX. The evolved catalytic activity with DEVX was enhanced 26-fold relative to wild-type PTE. Further improvements were facilitated by targeted error-prone PCR mutagenesis of loop-7, and additional PTE variants were identified with up to a 78-fold increase in the rate of DEVX hydrolysis. The best mutant hydrolyzed the racemic nerve agent VX with a value of kcat/Km = 7 × 10(4) M(-1) s(-1), a 230-fold improvement relative to wild-type PTE. The highest turnover number achieved by the mutants created for this investigation was 137 s(-1), an enhancement of 152-fold relative to wild-type PTE. The stereoselectivity for the hydrolysis of the two enantiomers of VX was relatively low. These engineered mutants of PTE are the best catalysts ever reported for the hydrolysis of nerve agent VX. PMID:23789980

  13. Using metal complex ion-molecule reactions in a miniature rectilinear ion trap mass spectrometer to detect chemical warfare agents.

    PubMed

    Graichen, Adam M; Vachet, Richard W

    2013-06-01

    The gas-phase reactions of a series of coordinatively unsaturated [Ni(L)n](y+) complexes, where L is a nitrogen-containing ligand, with chemical warfare agent (CWA) simulants in a miniature rectilinear ion trap mass spectrometer were investigated as part of a new approach to detect CWAs. Results show that upon entering the vacuum system via a poly(dimethylsiloxane) (PDMS) membrane introduction, low concentrations of several CWA simulants, including dipropyl sulfide (simulant for mustard gas), acetonitrile (simulant for the nerve agent tabun), and diethyl phosphite (simulant for nerve agents sarin, soman, tabun, and VX), can react with metal complex ions generated by electrospray ionization (ESI), thereby providing a sensitive means of detecting these compounds. The [Ni(L)n](2+) complexes are found to be particularly reactive with the simulants of mustard gas and tabun, allowing their detection at low parts-per-billion (ppb) levels. These detection limits are well below reported exposure limits for these CWAs, which indicates the applicability of this new approach, and are about two orders of magnitude lower than electron ionization detection limits on the same mass spectrometer. The use of coordinatively unsaturated metal complexes as reagent ions offers the possibility of further tuning the ion-molecule chemistry so that desired compounds can be detected selectively or at even lower concentrations. PMID:23532782

  14. Using Metal Complex Ion-Molecule Reactions in a Miniature Rectilinear Ion Trap Mass Spectrometer to Detect Chemical Warfare Agents

    NASA Astrophysics Data System (ADS)

    Graichen, Adam M.; Vachet, Richard W.

    2013-06-01

    The gas-phase reactions of a series of coordinatively unsaturated [Ni(L)n]y+ complexes, where L is a nitrogen-containing ligand, with chemical warfare agent (CWA) simulants in a miniature rectilinear ion trap mass spectrometer were investigated as part of a new approach to detect CWAs. Results show that upon entering the vacuum system via a poly(dimethylsiloxane) (PDMS) membrane introduction, low concentrations of several CWA simulants, including dipropyl sulfide (simulant for mustard gas), acetonitrile (simulant for the nerve agent tabun), and diethyl phosphite (simulant for nerve agents sarin, soman, tabun, and VX), can react with metal complex ions generated by electrospray ionization (ESI), thereby providing a sensitive means of detecting these compounds. The [Ni(L)n]2+ complexes are found to be particularly reactive with the simulants of mustard gas and tabun, allowing their detection at low parts-per-billion (ppb) levels. These detection limits are well below reported exposure limits for these CWAs, which indicates the applicability of this new approach, and are about two orders of magnitude lower than electron ionization detection limits on the same mass spectrometer. The use of coordinatively unsaturated metal complexes as reagent ions offers the possibility of further tuning the ion-molecule chemistry so that desired compounds can be detected selectively or at even lower concentrations.

  15. Development and application of acute exposure guideline levels (AEGLs) for chemical warfare nerve and sulfur mustard agents.

    PubMed

    Watson, Annetta; Opresko, Dennis; Young, Robert; Hauschild, Veronique

    2006-01-01

    Acute exposure guideline levels (AEGLs) have been developed for the chemical warfare agents GB, GA, GD, GF, VX, and sulfur mustard. These AEGLs were approved by the National Advisory Committee for Acute Exposure Guideline Levels for Hazardous Substances after Federal Register publication and comment, and judged as scientifically valid by the National Research Council Committee on Toxicology Subcommittee on AEGLs. AEGLs represent general public exposure limits for durations ranging from 10 min to 8 h, and for three levels of severity (AEGL-1, AEGL-2, AEGL-3). Mild effects are possible at concentrations greater than AEGL-1, while life-threatening effects are expected at concentrations greater than AEGL-3. AEGLs can be applied to various civilian and national defense purposes, including evacuation and shelter-in-place protocols, reentry levels, protective clothing specifications, and analytical monitoring requirements. This report documents development and derivation of AEGL values for six key chemical warfare agents, and makes recommendations for their application to various potential exposure scenarios. PMID:16621779

  16. Ionization mechanism of the ambient pressure pyroelectric ion source (APPIS) and its applications to chemical nerve agent detection.

    PubMed

    Neidholdt, Evan L; Beauchamp, J L

    2009-11-01

    We present studies of the ionization mechanism operative in the ambient pressure pyroelectric ionization source (APPIS), along with applications that include detection of simulants for chemical nerve agents. It is found that ionization by APPIS occurs in the gas-phase. As the crystal is thermally cycled over a narrow temperature range, electrical discharges near the surface of the crystal produce energetic species which, through reactions with atmospheric molecules, result in reactant ions such as protonated water clusters or clusters of hydroxide and water. Reactant ions can be observed directly in the mass spectrometer. These go on to react with trace neutrals via proton transfer reactions to produce the ions observed in mass spectra, which are usually singly protonated or deprotonated species. Further implicating gas-phase ionization, observed product distributions are highly dependent on the composition of ambient gases, especially the concentration of water vapor and oxygen surrounding the source. For example, basic species such as triethylamine are observed as singly protonated cations at a water partial pressure of 10 torr. At a water pressure of 4 torr, reactive oxygen species are formed and lead to observation of protonated amine oxides. The ability of the APPIS source to detect basic molecules with high proton affinities makes it highly suited for the detection of chemical nerve agents. We demonstrate this application using simulants corresponding to VX and GA (Tabun). With the present source configuration pyridine is detected readily at a concentration of 4 ppm, indicating ultimate sensitivity in the high ppb range. PMID:19682922

  17. Development and Application of Acute Exposure Guideline Levels (AEGLs) for Chemical Warfare Nerve and Sulfur Mustard Agents.

    SciTech Connect

    Watson, Annetta Paule; Opresko, Dennis M; Young, Robert A; Hauschild, Veronique

    2006-01-01

    Acute exposure guideline levels (AEGLs) have been developed for the chemical warfare agents GB, GA, GD, GF, VX, and sulfur mustard. These AEGLs were approved by the National Advisory Committee for Acute Exposure Guideline Levels for Hazardous Substances after Federal Register publication and comment, and judged as scientifically valid by the National Research Council Committee on Toxicology Subcommittee on AEGLs. AEGLs represent general public exposure limits for durations ranging from 10 min to 8 h, and for three levels of severity (AEGL-1, AEGL-2, AEGL-3). Mild effects are possible at concentrations greater than AEGL-1, while life-threatening effects are expected at concentrations greater than AEGL-3. AEGLs can be applied to various civilian and national defense purposes, including evacuation and shelter-in-place protocols, reentry levels, protective clothing specifications, and analytical monitoring requirements. This report documents development and derivation of AEGL values for six key chemical warfare agents, and makes recommendations for their application to various potential exposure scenarios.

  18. Bridging the gap between sample collection and laboratory analysis: using dried blood spots to identify human exposure to chemical agents

    NASA Astrophysics Data System (ADS)

    Hamelin, Elizabeth I.; Blake, Thomas A.; Perez, Jonas W.; Crow, Brian S.; Shaner, Rebecca L.; Coleman, Rebecca M.; Johnson, Rudolph C.

    2016-05-01

    Public health response to large scale chemical emergencies presents logistical challenges for sample collection, transport, and analysis. Diagnostic methods used to identify and determine exposure to chemical warfare agents, toxins, and poisons traditionally involve blood collection by phlebotomists, cold transport of biomedical samples, and costly sample preparation techniques. Use of dried blood spots, which consist of dried blood on an FDA-approved substrate, can increase analyte stability, decrease infection hazard for those handling samples, greatly reduce the cost of shipping/storing samples by removing the need for refrigeration and cold chain transportation, and be self-prepared by potentially exposed individuals using a simple finger prick and blood spot compatible paper. Our laboratory has developed clinical assays to detect human exposures to nerve agents through the analysis of specific protein adducts and metabolites, for which a simple extraction from a dried blood spot is sufficient for removing matrix interferents and attaining sensitivities on par with traditional sampling methods. The use of dried blood spots can bridge the gap between the laboratory and the field allowing for large scale sample collection with minimal impact on hospital resources while maintaining sensitivity, specificity, traceability, and quality requirements for both clinical and forensic applications.

  19. Simultaneous Measurement of Serum Chemical Castration Agents and Testosterone Levels Using Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry.

    PubMed

    Ko, Dae-Hyun; Lee, Kyunghoon; Jeon, Sun-Hee; Song, Sang Hoon; Yun, Yeo-Min; Chun, Sail; Kim, Hee Seung; Kim, Jin Young; In, Moon Kyo; Song, Junghan

    2016-05-01

    Chemical castration involves administration of drugs to prevent pathological sexual behavior, reduce abnormal sexual drive and treat hormone-dependent cancers. Various drugs have been used for chemical castration; however, substantial interindividual variability and side effects are often observed. In this study, we proposed a useful monitoring method for the application of chemical castration agents using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS). Testosterone, cyproterone acetate, medroxyprogesterone, goserelin acetate, leuprolide acetate and triptorelin acetate were analyzed by UPLC-MS-MS. The target drugs were extracted from serum samples by double protein precipitation using methanol. Testosterone-1,2-d2 and buserelin acetate were used as internal standards. Parameters of analytical performance were evaluated, including imprecision, linearity, ion suppression and detection capabilities. Testosterone measurements were compared with the results of immunoassays. Serum specimens from 51 subjects who underwent chemical castration were analyzed. All drugs and testosterone were well extracted and separated using our method. The method was essentially free from potential interferences and ion suppression. Within-run and between-run imprecision values were <15%. The lower limits of quantification were 0.125 and 0.5-1.0 ng/mL for testosterone and other drugs, respectively. Good correlations with pre-existing immunoassays for testosterone measurement were observed. Sera from subjects who underwent androgen deprivation therapy showed variable levels of drugs. We successfully developed a UPLC-MS-MS-based monitoring method for chemical castration. The performance of our method was generally acceptable. This method may provide a novel monitoring strategy for chemical castration to enhance expected effects while reducing unwanted side effects. PMID:26989223

  20. Thiolates Chemically Induce Redox Activation of BTZ043 and Related Potent Nitro Aromatic Anti-Tuberculosis Agents

    PubMed Central

    Tiwari, Rohit; Moraski, Garrett C.; Krchňák, Viktor; Miller, Patricia A.; Colon-Martinez, Mariangelli; Herrero, Eliza; Oliver, Allen G.; Miller, Marvin J.

    2013-01-01

    The development of multidrug resistant (MDR) and extensively drug resistant (XDR) forms of tuberculosis (TB) has stimulated research efforts globally to expand the new drug pipeline. Nitro aromatic compounds, including 1, 3-Benzothiazin-4-ones (BTZs) and related agents, are a promising new class for the treatment of TB. Research has shown that the nitroso intermediates of BTZs that are generated in vivo cause suicide inhibition of decaprenylphosphoryl-β-D-ribose 2′ oxidase (DprE1), which is responsible for cell wall arabinogalactan biosynthesis. We have designed and synthesized novel anti-TB agents inspired from BTZs and other nitroaromatic compounds. Computational studies indicated that the unsubstituted aromatic carbons of BTZ043 and related nitroaromatic compounds are the most electron deficient and might be prone to nucleophilic attack. Our chemical studies on BTZ043 and the additional nitro aromatic compounds synthesized by us and the others confirmed the postulated reactivity. The results indicate that nucleophiles such as thiolates, cyanide and hydride induce non-enzymatic reduction of the nitro groups present in these compounds to the corresponding nitroso intermediates by addition at the unsubstituted electron deficient aromatic carbon present in these compounds. Furthermore we demonstrate here that these compounds are good candidates for the classical von Richter reaction. These chemical studies offer an alternate hypotheses for the mechanism of action of nitro aromatic anti-TB agents in that the cysteine thiol(ate) or a hydride source at the active site of DprE1 may trigger the reduction of the nitro groups in a manner similar to the von Richter reaction to the nitroso intermediates, to initiate the inhibition of DprE1. PMID:23402278

  1. Soft x-ray measurements using photoconductive type-IIa and single-crystal chemical vapor deposited diamond detectors

    SciTech Connect

    Moore, A. S.; Bentley, C. D.; Foster, J. M.; Goedhart, G.; Graham, P.; Taylor, M. J.; Hellewell, E.

    2008-10-15

    Photoconductive detectors (PCDs) are routinely used alongside vacuum x-ray diodes (XRDs) to provide an alternative x-ray flux measurement at laser facilities such as HELEN at AWE Aldermaston, UK, and Omega at the Laboratory for Laser Energetics. To evaluate diamond PCDs as an alternative to XRD arrays, calibration measurements made at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory are used to accurately calculate the x-ray flux from a laser-heated target. This is compared to a flux measurement using the Dante XRD diagnostic. Estimates indicate that the photoinduced conductivity from measurements made at Omega are too large, and calculations using the radiometric calibrations made at the NSLS agree with this hypothesis. High-purity, single-crystal, chemical vapor deposited (CVD) diamond samples are compared to natural type-IIa PCDs and show promising high resistivity effects, the corollary of which preliminary results show is a slower response time.

  2. Probing the Chemical Stability of Mixed Ferrites: Implications for MR Contrast Agent Design

    PubMed Central

    Schultz-Sikma, Elise A.; Joshi, Hrushikesh M.; Ma, Qing; MacRenaris, Keith W.; Eckermann, Amanda L.; Dravid, Vinayak P.; Meade, Thomas J.

    2011-01-01

    Nanomaterials with mixed composition, in particular magnetic spinel ferrites, are emerging as efficient contrast agents for magnetic resonance imaging (MRI). Many factors, including size, composition, atomic structure, and surface properties are crucial in the design of such nanoparticle-based probes due to their influence on the magnetic properties. Silica-coated iron oxide (IO-SiO2) and cobalt ferrite (CoIO-SiO2) nanoparticles were synthesized using standard high temperature thermal decomposition and base-catalyzed water-in-oil microemulsion techniques. Under neutral aqueous conditions, it was found that 50–75% of the cobalt content in the CoIO-SiO2 nanoparticles leached out of the core structure. Leaching caused a 7.2-fold increase in longitudinal relaxivity and an increase in the saturation magnetization from ~48 emu/g core to ~65 emu/g core. X-ray absorption fine structure studies confirmed that the atomic structure of the ferrite core was altered following leaching, while TEM and DLS confirmed that the morphology and size of the nanoparticle remained unchanged. The CoIO-SiO2 nanoparticles converted from a partially inverted spinel cation arrangement (unleached state) to an inverse spinel arrangement (leached state). The control IO-SiO2 nanoparticles remained stable with no change in structure and negligible changes in magnetic behavior. This detailed analysis highlights how important understanding the properties of nanomaterials is in the development of reliable agents for diagnostic and therapeutic applications. PMID:21603070

  3. Overcoming Heterogeneity Effects Through Polymer-Enhanced Groundwater Remediation Techniques: Coupling Polymer Floods with Chemical Oxidants and Bio-agents

    NASA Astrophysics Data System (ADS)

    Smith, M. M.; Silva, J. A.; Munakata-Marr, J.; McCray, J. E.

    2008-12-01

    Even small heterogeneity contrasts in contaminated systems (resulting from differences in permeability or contaminant saturation) can affect the distribution of injected remediation agents by channeling fluids through high-permeability flowpaths, thus bypassing some regions and leaving contaminants uncontacted. The addition of a viscous polymer solution to the remediation agent may enhance agent delivery as a result of increased cross-flow (or "sweep efficiency") into different layers of the system, if the polymer solution remains stable in the presence of the remediation agent. Our research combines various non-toxic, food- grade polymer solutions with the remediation techniques of chemical oxidation and bio-remediation, to increase the effectiveness of treatment at sites contaminated with non-aqueous phase liquids (NAPLs). The coupling of polymer floods with oxidants may help to combat contaminant "rebound" sometimes associated with incomplete contaminant destruction in low-permeability zones. Initial compatibility testing has shown that certain robust polymer/oxidant mixtures possess stable viscosities and pose low additional oxidant demands over multi-day timescales. Transport of these solutions through natural porous media was studied in column experiments, and small two-dimensional experiments with heterogeneous layering were conducted to assess effectiveness of contaminant destruction. Limitations of these compatible polymer/oxidant combinations as well as possible experimental strategies to optimize delivery are also discussed. In addition, results of polymer/microbial screening tests reveal that polymer solutions do not inhibit the dechlorinating capabilities of a microbial consortium. Preliminary findings have also raised the possibility that certain polymers may successfully serve as electron donors in the subsurface. The implications of these results for either bioaugmentation or delivery of biostimulants are presented.

  4. Physico-chemical stability of astaxanthin nanodispersions prepared with polysaccharides as stabilizing agents.

    PubMed

    Anarjan, Navideh; Tan, Chin Ping

    2013-09-01

    The emulsification and stabilization ability of four selected polysaccharides, namely, gum Arabic, xanthan gum, pectin and methyl cellulose, in the preparation of water-dispersible astaxanthin nanoparticles using the emulsification-evaporation technique was investigated in this study. The chemical and molecular structure of polysaccharides had significant effects (p < 0.05) on the physicochemical properties of the prepared astaxanthin nanodispersions. Among all prepared nanodispersions, sample produced and stabilized using gum Arabic showed the smallest average particle size (295 nm) and highest physical stability. The observed considerable degradation of astaxanthin in the resulting nanodispersions during processing (24-70% w/w) and storage at 10 °C for 30 d (86-96% w/w) illustrated the limited chemical stability of polysaccharide-stabilized nanodispersions. PMID:23590613

  5. A Low-Waste Electrospray Method for Applying Chemicals and Finishing Agents to Textiles Zh

    SciTech Connect

    Alexander, D.A.; Zhang, X.

    1999-08-01

    This electrospray technology works by applying the desired chemicals onto a substrate as electrically generated, charged sprays. By imposing a potential difference between the application nozzle and the target, it is possible to precisely direct and control the spray. This electrospray method of application gives a small droplet size and a relatively uniform size distribution, with the added advantage of an easily controllable spray angle. It potentially offers substantial improvement over traditional methods in the area of application uniformity, resulting in improved product quality. Additionally, since the chemicals are electrically directed straight onto the fiber with a minimum of overspray, the electrospray method holds promise in the area of waste reduction, resulting in lowered production cost.

  6. Disposal of chemical agents and munitions stored at Anniston Army Depot, Anniston, Alabama

    SciTech Connect

    Hunsaker, D.B. Jr.; Zimmerman, G.P.; Staub, W.P.; Hillsman, E.L.

    1990-09-01

    This is the 1990 Addendum (Volume 2) for the Phase I report on the disposal of chemicals and munitions at Anniston Army Depot. Included in the Addendum are responses to reviewers' comments on population density estimates, seismicity information, fault locations, and references. Reviewing agencies errata, and conclusions are also listed. Information presented does not change the principal conclusion reached by the Phase I report, that on-site disposal remains valid for Anniston Army Depot. (SM)

  7. Cancer of the mouth and pharynx, occupation and exposure to chemical agents in Finland [in 1971-95].

    PubMed

    Tarvainen, Laura; Kyyrönen, Pentti; Kauppinen, Timo; Pukkala, Eero

    2008-08-01

    The objective of this article was to find associations between cancer of the mouth and pharynx, occupation and chemical exposure. A cohort of Finns born between 1906 and 1945 was followed-up for 46.8 (21.5 in males and 25.3 in females) million person-years during 1971-95. Incident cases of cancer of the mouth and pharynx (n = 2,708) were identified in a record linkage with the Finnish Cancer Registry. The Census occupations in 1970 were converted to chemical exposures with a job-exposure matrix (FINJEM). Cumulative exposure (CE) was calculated as the product of prevalence, level and duration of the exposure. Standardized incidence ratio (SIR) was calculated for each of the 393 occupations, and for CE categories of the 43 chemical agents, using total Finnish population as reference. Relative risks (RR) comparing various CE-categories with unexposed ones were defined for selected agents by Poisson regression analysis. Elevated SIRs were observed among lawyers, authors, journalists, performing artists, musicians, electronics and telefitters, painters (building), building hands, dockers, unskilled labourers and hotel porters in males and private secretaries, dressmakers, shoemakers and cobblers, waiters, pursers and stewardesses in females. The multivariate analyses showed high RRs for high exposure to aliphatic and alicyclic hydrocarbons, pesticides and alcohol. In conclusion, occupations with high SIRs were mostly the ones with high consumption of alcohol. Exposure to solvents and possibly to pesticides, engine exhaust, textile dust and leather dust may increase the risk of cancer of mouth and pharynx. PMID:18470913

  8. Dynamic 3-D chemical agent cloud mapping using a sensor constellation deployed on mobile platforms

    NASA Astrophysics Data System (ADS)

    Cosofret, Bogdan R.; Konno, Daisei; Rossi, David; Marinelli, William J.; Seem, Pete

    2014-05-01

    The need for standoff detection technology to provide early Chem-Bio (CB) threat warning is well documented. Much of the information obtained by a single passive sensor is limited to bearing and angular extent of the threat cloud. In order to obtain absolute geo-location, range to threat, 3-D extent and detailed composition of the chemical threat, fusion of information from multiple passive sensors is needed. A capability that provides on-the-move chemical cloud characterization is key to the development of real-time Battlespace Awareness. We have developed, implemented and tested algorithms and hardware to perform the fusion of information obtained from two mobile LWIR passive hyperspectral sensors. The implementation of the capability is driven by current Nuclear, Biological and Chemical Reconnaissance Vehicle operational tactics and represents a mission focused alternative of the already demonstrated 5-sensor static Range Test Validation System (RTVS).1 The new capability consists of hardware for sensor pointing and attitude information which is made available for streaming and aggregation as part of the data fusion process for threat characterization. Cloud information is generated using 2-sensor data ingested into a suite of triangulation and tomographic reconstruction algorithms. The approaches are amenable to using a limited number of viewing projections and unfavorable sensor geometries resulting from mobile operation. In this paper we describe the system architecture and present an analysis of results obtained during the initial testing of the system at Dugway Proving Ground during BioWeek 2013.

  9. Gene expression pattern recognition algorithm inferences to classify samples exposed to chemical agents

    NASA Astrophysics Data System (ADS)

    Bushel, Pierre R.; Bennett, Lee; Hamadeh, Hisham; Green, James; Ableson, Alan; Misener, Steve; Paules, Richard; Afshari, Cynthia

    2002-06-01

    We present an analysis of pattern recognition procedures used to predict the classes of samples exposed to pharmacologic agents by comparing gene expression patterns from samples treated with two classes of compounds. Rat liver mRNA samples following exposure for 24 hours with phenobarbital or peroxisome proliferators were analyzed using a 1700 rat cDNA microarray platform. Sets of genes that were consistently differentially expressed in the rat liver samples following treatment were stored in the MicroArray Project System (MAPS) database. MAPS identified 238 genes in common that possessed a low probability (P < 0.01) of being randomly detected as differentially expressed at the 95% confidence level. Hierarchical cluster analysis on the 238 genes clustered specific gene expression profiles that separated samples based on exposure to a particular class of compound.

  10. Probing the Chemical Stability of Mixed Ferrites: Implications for Magnetic Resonance Contrast Agent Design

    SciTech Connect

    Schultz-Sikma, Elise A.; Joshi, Hrushikesh M.; Ma, Qing; MacRenaris, Keith W.; Eckermann, Amanda L.; Dravid, Vinayak P.; Meade, Thomas J.

    2011-09-16

    Nanomaterials with mixed composition, in particular magnetic spinel ferrites, are emerging as efficient contrast agents for magnetic resonance imaging. Many factors, including size, composition, atomic structure, and surface properties, are crucial in the design of such nanoparticle-based probes because of their influence on the magnetic properties. Silica-coated iron oxide (IO-SiO{sub 2}) and cobalt ferrite (CoIO-SiO{sub 2}) nanoparticles were synthesized using standard high-temperature thermal decomposition and base-catalyzed water-in-oil microemulsion techniques. Under neutral aqueous conditions, it was found that 50-75% of the cobalt content in the CoIO-SiO{sub 2} nanoparticles leached out of the core structure. Leaching caused a 7.2-fold increase in the longitudinal relaxivity and an increase in the saturation magnetization from {approx}48 to {approx}65 emu/g of the core. X-ray absorption fine structure studies confirmed that the atomic structure of the ferrite core was altered following leaching, while transmission electron microscopy and dynamic light scattering confirmed that the morphology and size of the nanoparticle remained unchanged. The CoIO-SiO{sub 2} nanoparticles converted from a partially inverted spinel cation arrangement (unleached state) to an inverse spinel arrangement (leached state). The control IO-SiO{sub 2} nanoparticles remained stable with no change in the structure and negligible changes in the magnetic behavior. This detailed analysis highlights how important understanding the properties of nanomaterials is in the development of reliable agents for diagnostic and therapeutic applications.

  11. Decontamination of chemical warfare sulfur mustard agent simulant by ZnO nanoparticles

    NASA Astrophysics Data System (ADS)

    Sadeghi, Meysam; Yekta, Sina; Ghaedi, Hamed

    2016-07-01

    In this study, zinc oxide nanoparticles (ZnO NPs) have been surveyed to decontaminate the chloroethyl phenyl sulfide as a sulfur mustard agent simulant. Prior to the reaction, ZnO NPs were successfully prepared through sol-gel method in the absence and presence of polyvinyl alcohol (PVA). PVA was utilized as a capping agent to control the agglomeration of the nanoparticles. The formation, morphology, elemental component, and crystalline size of nanoscale ZnO were certified and characterized by SEM/EDX, XRD, and FT-IR techniques. The decontamination (adsorption and destruction) was tracked by the GC-FID analysis, in which the effects of polarity of the media, such as isopropanol, acetone and n-hexane, reaction time intervals from 1 up to 18 h, and different temperatures, including 25, 35, 45, and 55 °C, on the catalytic/decontaminative capability of the surface of ZnO NPs/PVA were investigated and discussed, respectively. Results demonstrated that maximum decontamination (100 %) occurred in n-hexane solvent at 55 °C after 1 h. On the other hand, the obtained results for the acetone and isopropanol solvents were lower than expected. GC-MS chromatograms confirmed the formation of hydroxyl ethyl phenyl sulfide and phenyl vinyl sulfide as the destruction reaction products. Furthermore, these chromatograms proved the role of hydrolysis and elimination mechanisms on the catalyst considering its surface Bronsted and Lewis acid sites. A non-polar solvent aids material transfer to the reactive surface acid sites without blocking these sites.

  12. Variants of Phosphotriesterase for the Enhanced Detoxification of the Chemical Warfare Agent VR.

    PubMed

    Bigley, Andrew N; Mabanglo, Mark F; Harvey, Steven P; Raushel, Frank M

    2015-09-01

    The V-type organophosphorus nerve agents are among the most hazardous compounds known. Previous efforts to evolve the bacterial enzyme phosphotriesterase (PTE) for the hydrolytic decontamination of VX resulted in the identification of the variant L7ep-3a, which has a kcat value more than 2 orders of magnitude higher than that of wild-type PTE for the hydrolysis of VX. Because of the relatively small size of the O-ethyl, methylphosphonate center in VX, stereoselectivity is not a major concern. However, the Russian V-agent, VR, contains a larger O-isobutyl, methylphosphonate center, making stereoselectivity a significant issue since the SP-enantiomer is expected to be significantly more toxic than the RP-enantiomer. The three-dimensional structure of the L7ep-3a variant was determined to a resolution of 2.01 Å (PDB id: 4ZST ). The active site of the L7ep-3a mutant has revealed a network of hydrogen bonding interactions between Asp-301, Tyr-257, Gln-254, and the hydroxide that bridges the two metal ions. A series of new analogues that mimic VX and VR has helped to identify critical structural features for the development of new enzyme variants that are further enhanced for the catalytic detoxification of VR and VX. The best of these mutants has been shown to have a reversed stereochemical preference for the hydrolysis of VR-chiral center analogues. This mutant hydrolyzes the two enantiomers of VR 160- and 600-fold faster than wild-type PTE hydrolyzes the SP-enantiomer of VR. PMID:26274608

  13. A Micro-Cantilever Based Photoacoustic Detector of Terahertz Radiation for Chemical Sensing

    NASA Astrophysics Data System (ADS)

    Glauvitz, Nathan E.; Coutu, Ronald A. Coutu, Jr.; Kistler, Michael N.; Hamilton, Ryan F.; Petkie, Douglas T.; Medvedev, Ivan R.

    2013-06-01

    In this paper we describe a novel photoacoustic detector that can detect radiation in the Terahertz/sub-millimeter (THz/smm) spectral range, is immune to the effect of standing waves, and potentially can have spectral response that is independent of the absorption path length, thus offering crucial advantages for acquisition of THz/smm molecular spectra. The photoacoustic effect occurs when the energy from electromagnetic waves is absorbed by molecules and collisionally transferred into translational energy, thus resulting in local heating induced by the radiation. If radiation produced by the source is modulated, an acoustic wave results which can be detected by a pressure sensitive device such as a microphone or a cantilever. This transduction of the THz signal into a photoacoustic wave is what makes this approach insensitive to the detrimental standing waves associated with traditional THz sensors and allows for a significant reduction in the size of the absorption cell. A Microelectromechanical system (MEMS) cantilever pressure sensor was designed, modeled, fabricated, and tested for sensing the photoacoustic response of gases to THz/smm radiation. Here we present our manufacturing, experimental set-up and most recent spectroscopic results, which demonstrate the capabilities of this spectroscopic technique.

  14. Sensitive monitoring of volatile chemical warfare agents in air by atmospheric pressure chemical ionization mass spectrometry with counter-flow introduction.

    PubMed

    Seto, Yasuo; Kanamori-Kataoka, Mieko; Tsuge, Koichiro; Ohsawa, Isaac; Iura, Kazumitsu; Itoi, Teruo; Sekiguchi, Hiroyuki; Matsushita, Koji; Yamashiro, Shigeharu; Sano, Yasuhiro; Sekiguchi, Hiroshi; Maruko, Hisashi; Takayama, Yasuo; Sekioka, Ryoji; Okumura, Akihiko; Takada, Yasuaki; Nagano, Hisashi; Waki, Izumi; Ezawa, Naoya; Tanimoto, Hiroyuki; Honjo, Shigeru; Fukano, Masumi; Okada, Hidehiro

    2013-03-01

    A new method for sensitively and selectively detecting chemical warfare agents (CWAs) in air was developed using counter-flow introduction atmospheric pressure chemical ionization mass spectrometry (MS). Four volatile and highly toxic CWAs were examined, including the nerve gases sarin and tabun, and the blister agents mustard gas (HD) and Lewisite 1 (L1). Soft ionization was performed using corona discharge to form reactant ions, and the ions were sent in the direction opposite to the airflow by an electric field to eliminate the interfering neutral molecules such as ozone and nitrogen oxide. This resulted in efficient ionization of the target CWAs, especially in the negative ionization mode. Quadrupole MS (QMS) and ion trap tandem MS (ITMS) instruments were developed and investigated, which were movable on the building floor. For sarin, tabun, and HD, the protonated molecular ions and their fragment ions were observed in the positive ion mode. For L1, the chloride adduct ions of L1 hydrolysis products were observed in negative ion mode. The limit of detection (LOD) values in real-time or for a 1 s measurement monitoring the characteristic ions were between 1 and 8 μg/m(3) in QMS instrument. Collision-induced fragmentation patterns for the CWAs were observed in an ITMS instrument, and optimized combinations of the parent and daughter ion pairs were selected to achieve real-time detection with LOD values of around 1 μg/m(3). This is a first demonstration of sensitive and specific real-time detection of both positively and negatively ionizable CWAs by MS instruments used for field monitoring. PMID:23339735

  15. Secondary ionization of chemical warfare agent simulants: atmospheric pressure ion mobility time-of-flight mass spectrometry.

    PubMed

    Steiner, Wes E; Clowers, Brian H; Haigh, Paul E; Hill, Herbert H

    2003-11-15

    For the first time, the use of a traditional ionization source for ion mobility spectrometry (radioactive nickel ((63)Ni) beta emission ionization) and three alternative ionization sources (electrospray ionization (ESI), secondary electrospray ionization (SESI), and electrical discharge (corona) ionization (CI)) were employed with an atmospheric pressure ion mobility orthogonal reflector time-of-flight mass spectrometer (IM(tof)MS) to detect chemical warfare agent (CWA) simulants from both aqueous- and gas-phase samples. For liquid-phase samples, ESI was used as the sample introduction and ionization method. For the secondary ionization (SESI, CI, and traditional (63)Ni ionization) of vapor-phase samples, two modes of sample volatilization (heated capillary and thermal desorption chamber) were investigated. Simulant reference materials, which closely mimic the characteristic chemical structures of CWA as defined and described by Schedule 1, 2, or 3 of the Chemical Warfare Convention treaty verification, were used in this study. A mixture of four G/V-type nerve simulants (dimethyl methylphosphonate, pinacolyl methylphosphonate, diethyl phosphoramidate, and 2-(butylamino)ethanethiol) and one S-type vesicant simulant (2-chloroethyl ethyl sulfide) were found in each case (sample ionization and introduction methods) to be clearly resolved using the IM(tof)MS method. In many cases, reduced mobility constants (K(o)) were determined for the first time. Ion mobility drift times, flight times, relative signal intensities, and fragmentation product signatures for each of the CWA simulants are reported for each of the methods investigated. PMID:14615983

  16. Chemical agent identification by field-based attenuated total reflectance infrared detection and solid-phase microextraction.

    PubMed

    Bryant, Chet K; LaPuma, Peter T; Hook, Gary L; Houser, Eric J

    2007-03-15

    Attenuated total reflectance Fourier transform infrared (ATR-FT-IR) spectroscopy is used to identify liquid and solid-phase chemicals. This research examines the feasibility of identifying vapor-phase chemicals using a field-portable ATR-FT-IR spectrometer (TravelIR) combined with solid-phase microextraction (SPME). Two nerve agent simulants, diisopropyl methylphosphonate (DIMP) and di-methyl methylphosphonate (DMMP), and three sorbent polymers were evaluated. Each polymer was deposited as a thin film on the instrument's sampling interface to partition and concentrate the simulants from air samples prepared in Tedlar bags. The lowest vapor concentrations identified were 50 ppb (v/v) (DIMP) and 250 ppb (v/v) (DMMP). The ATR-FT-IR instrument demonstrated a linear response at concentrations of 1 ppm (v/v) and below. Increasing the sample exposure time, the sample air velocity, and the film thickness was demonstrated to increase the amount of analyte extracted from the air sample. This research demonstrates that it is feasible to use a portable ATR-FT-IR spectrometer with SPME sampling to detect and identify vapor-phase chemicals. PMID:17284014

  17. Distribution of chemical warfare agent, energetics, and metals in sediments at a deep-water discarded military munitions site

    NASA Astrophysics Data System (ADS)

    Briggs, Christian; Shjegstad, Sonia M.; Silva, Jeff A. K.; Edwards, Margo H.

    2016-06-01

    There is a strong need to understand the behavior of chemical warfare agent (CWA) at underwater discarded military munitions (DMM) sites to determine the potential threat to human health or the environment, yet few studies have been conducted at sites in excess of 250 m, the depth at which most U.S. chemical munitions were disposed. As part of the Hawai'i Undersea Military Munitions Assessment (HUMMA), sediments adjacent to chemical and conventional DMM at depths of 400-650 m were sampled using human occupied vehicles (HOVs) in order to quantify the distribution of CWA, energetics, and select metals. Sites in the same general area, with no munitions within 50 m in any direction were sampled as a control. Sulfur mustard (HD) and its degradation product 1,4-dithiane were detected at each CWA DMM site, as well as a single sample with the HD degradation product 1,4-thioxane. An energetic compound was detected in sediment to a limited extent at one CWA DMM site. Metals common in munitions casings (i.e., Fe, Cu, and Pb) showed similar trends at the regional and site-wide scales, likely reflecting changes in marine sediment deposition and composition. This study shows HD and its degradation products can persist in the deep-marine environment for decades following munitions disposal.

  18. Fast neutron sensor for detection of explosives and chemical warfare agents.

    PubMed

    Valkovic, Vladivoj; Sudac, Davorin; Matika, Dario

    2010-01-01

    Once the presence of the anomaly on the bottom of the shallow coastal sea water has been confirmed it is necessary to establish if it contains explosive or chemical warfare charge. We propose that this be performed by using neutron sensor installed within an underwater vessel. When positioned above the object, or to its side, the system can inspect the object for the presence of the threat materials by using alpha particle tagged neutrons from the sealed tube d+t neutron generator. PMID:19833524

  19. Determination of decimal reduction time (D value) of chemical agents used in hospitals for disinfection purposes

    PubMed Central

    Mazzola, Priscila Gava; Penna, Thereza Christina Vessoni; da S Martins, Alzira M

    2003-01-01

    Background Prior to the selection of disinfectants for low, intermediate and high (sterilizing) levels, the decimal reduction time, D-value, for the most common and persistent bacteria identified at a health care facility should be determined. Methods The D-value was determined by inoculating 100 mL of disinfecting solution with 1 mL of a bacterial suspension (104 – 105 CFU/mL for vegetative and spore forms). At regular intervals, 1 mL aliquots of this mixture were transferred to 8 mL of growth media containing a neutralizing agent, and incubated at optimal conditions for the microorganism. Results The highest D-values for various bacteria were determined for the following solutions: (i) 0.1% sodium dichloroisocyanurate (pH 7.0) – E. coli and A. calcoaceticus (D = 5.9 min); (ii) sodium hypochlorite (pH 7.0) at 0.025% for B. stearothermophilus (D = 24 min), E. coli and E. cloacae (D = 7.5 min); at 0.05% for B. stearothermophilus (D = 9.4 min) and E. coli (D = 6.1 min) and 0.1% for B. stearothermophilus (D = 3.5 min) and B. subtilis (D = 3.2 min); (iii) 2.0% glutaraldehyde (pH 7.4) – B. stearothermophilus, B. subtilis (D = 25 min) and E. coli (D = 7.1 min); (iv) 0.5% formaldehyde (pH 6.5) – B. subtilis (D = 11.8 min), B. stearothermophilus (D = 10.9 min) and A. calcoaceticus (D = 5.2 min); (v) 2.0% chlorhexidine (pH 6.2) – B. stearothermophilus (D = 9.1 min), and at 0.4% for E. cloacae (D = 8.3 min); (vi) 1.0% Minncare® (peracetic acid and hydrogen peroxide, pH 2.3) – B. stearothermophilus (D = 9.1 min) and E. coli (D = 6.7 min). Conclusions The suspension studies were an indication of the disinfectant efficacy on a surface. The data in this study reflect the formulations used and may vary from product to product. The expected effectiveness from the studied formulations showed that the tested agents can be recommended for surface disinfection as stated in present guidelines and emphasizes the importance and need to develop routine and novel programs to

  20. [Technology upgrades and exposure to chemical agents: results of the PPTP study in the footwear industry].

    PubMed

    Gianoli, Enrica; Brusoni, Daniela; Cornaggia, Nicoletta; Saretto, Gianni

    2012-01-01

    In the present work the chemical compositions of the products used in shoes manufacturing are reported. The data were collected over the period 2004-2007 in 156 shoe factories in Vigevano area during a study aiming the evaluation of safety conditions and occupational exposure to hazardous chemicals of the employees. The study was part of a regional project for "Occupational cancer prevention in the footwear industry". In the first phase of the study an information form on production cycle, products used and their composition was filled during preliminary audit. In the second phase of the study an in depth qualitative/quantitative evaluation of professional exposure was conducted in 13 selected shoe factories. Data analysis showed the increase in use of water-based adhesives at expense of solvent-based adhesives, the reduction to less than 3.5 weight %, and up to 1 weight %, of n-hexane concentration in solvent mixtures, the increase in use of products containing less hazardous ketones, esters, cyclohexane and heptane. Only in very few cases, products containing from 4 to 12 weight% of toluene were used. These data attest a positive trend in workers risks prevention in shoes industry. PMID:22697030

  1. Neoplastic cell transformation by energetic heavy ions and its modification with chemical agents.

    PubMed

    Yang, T C; Tobias, C A

    1984-01-01

    For many years we have been interested in understanding the potential carcinogenic effects of cosmic rays. We have studied the oncogenic effects of cosmic rays with accelerator-produced heavy particle radiation and with a cultured mammalian cell system--C3H10T1/2 cells. Our quantitative data obtained with carbon, neon, silicon, and iron particles showed that RBE is both dose and LET dependent for neoplastic cell transformation. RBE is higher at lower dose, and RBE increases with LET up to about 200 keV/micrometer. In nonproliferation confluent cells, heavy-ion induced transformation damage may not be repairable, although a dose modifying factor of about 1.7 was observed for X-ray radiation. Our recent studies with super-heavy high-energy particles, e.g., 960 MeV/U U235 ions (LET = 1900 keV/micrometer), indicate that these ions with a high inactivation cross-section can cause neoplastic cell transformation. The induction of cell transformation by radiation can be modified with various chemicals. We have found that the presence of DMSO (either during or many days after irradiation) decreased the transformation frequency significantly. It is, therefore, potentially possible to reduce the oncogenic effect of cosmic rays in space through some chemical protection. PMID:11539629

  2. Neoplastic cell transformation by energetic heavy ions and its modification with chemical agents

    NASA Astrophysics Data System (ADS)

    Yang, T. C.; Tobias, C. A.

    For many years we have been interested in understanding the potential carcinogenic effects of cosmic rays. We have studied the oncogenic effects of cosmic rays with accelerator-produced heavy particle radiation and with a cultured mammalian cell system--C3H10T1/2 cells. Our quantitative data obtained with carbon, neon, silicon, and iron particles showed that RBE is both dose and LET dependent for neoplastic cell transformation. RBE is higher at lower dose, and RBE increases with LET up to about 200 keV/μm. In nonproliferation confluent cells, heavy-ion induced transformation damage may not be repairable, although a dose modifying factor of about 1.7 was observed for X-ray radiation. Our recent studies with super-heavy high-energy particles, e.g., 960 MeV/u U235 ions (LET = 1900 keV/μm), indicate that these ions with a high inactivation cross-section can cause neoplastic cell transformation. The induction of cell transformation by radiation can be modified with various chemicals. We have found that the presence of DMSO (either during or many days after irradiation) decreased the transformation frequency significantly. It is, therefore, potentially possible to reduce the oncogenic effect of cosmic rays in space through some chemical protection.

  3. Sensitizers on inorganic carriers for decomposition of the chemical warfare agent yperite.

    PubMed

    Cojocaru, Bogdan; Parvulescu, Vasile I; Preda, Elena; Iepure, Gabriel; Somoghi, Vasile; Carbonell, Esther; Alvaro, Mercedes; García, Hermenegildo

    2008-07-01

    Sulfur-containing compounds, such as mercaptans, alkali sulfides, alkali sulfites, and alkali thiosulfates, are byproducts of industrial processes and pollutants of waste and natural waters. Other sulfur-containing compounds such as yperite are dangerous chemical weapons. Efficient photocatalytic decomposition of these molecules is a process that can find applications in emergency situations or for the controlled destruction of chemical warfare stockpiles. A series of heterogeneous photocatalysts consisting of a metal phthalocyanine or 2,4,6-triphenylpyrylium as photoactive components encapsulated inside the cavities of zeolite Y or the mesoporous channels of MCM-41 or supported on silica or titania-silica was tested for the photocatalytic decomposition of yperite. Two types of photoreactors, either an open reactor naturally aerated or a closed quartz tube with a constant airflow using UV or visible ambient light were used. These tests demonstrated that iron and manganese phthalocyanine and 2,4,6-triphenylpyrylium embedded in NaY or titania-silica can be suitable solid photocatalysts for the degradation of yperite using UV and visible irradiation. PMID:18678025

  4. Chemical genetic profiling of the microtubule-targeting agent peloruside A in budding yeast Saccharomyces cerevisiae.

    PubMed

    Wilmes, Anja; Hanna, Reem; Heathcott, Rosemary W; Northcote, Peter T; Atkinson, Paul H; Bellows, David S; Miller, John H

    2012-04-15

    Peloruside A, a microtubule-stabilising agent from a New Zealand marine sponge, inhibits mammalian cell division by a similar mechanism to that of the anticancer drug paclitaxel. Wild type budding yeast Saccharomyces cerevisiae (haploid strain BY4741) showed growth sensitivity to peloruside A with an IC(50) of 35μM. Sensitivity was increased in a mad2Δ (Mitotic Arrest Deficient 2) deletion mutant (IC(50)=19μM). Mad2 is a component of the spindle-assembly checkpoint complex that delays the onset of anaphase in cells with defects in mitotic spindle assembly. Haploid mad2Δ cells were much less sensitive to paclitaxel than to peloruside A, possibly because the peloruside binding site on yeast tubulin is more similar to mammalian tubulin than the taxoid site where paclitaxel binds. In order to obtain information on the primary and secondary targets of peloruside A in yeast, a microarray analysis of yeast heterozygous and homozygous deletion mutant sets was carried out. Haploinsufficiency profiling (HIP) failed to provide hits that could be validated, but homozygous profiling (HOP) generated twelve validated genes that interact with peloruside A in cells. Five of these were particularly significant: RTS1, SAC1, MAD1, MAD2, and LSM1. In addition to its known target tubulin, based on these microarray 'hits', peloruside A was seen to interact genetically with other cell proteins involved in the cell cycle, mitosis, RNA splicing, and membrane trafficking. PMID:22326528

  5. Cerium oxide for the destruction of chemical warfare agents: A comparison of synthetic routes.

    PubMed

    Janoš, Pavel; Henych, Jiří; Pelant, Ondřej; Pilařová, Věra; Vrtoch, Luboš; Kormunda, Martin; Mazanec, Karel; Štengl, Václav

    2016-03-01

    Four different synthetic routes were used to prepare active forms of cerium oxide that are capable of destroying toxic organophosphates: a sol-gel process (via a citrate precursor), homogeneous hydrolysis and a precipitation/calcination procedure (via carbonate and oxalate precursors). The samples prepared via homogeneous hydrolysis with urea and the samples prepared via precipitation with ammonium bicarbonate (with subsequent calcination at 500°C in both cases) exhibited the highest degradation efficiencies towards the extremely dangerous nerve agents soman (O-pinacolyl methylphosphonofluoridate) and VX (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate) and the organophosphate pesticide parathion methyl. These samples were able to destroy more than 90% of the toxic compounds in less than 10 min. The high degradation efficiency of cerium oxide is related to its complex surface chemistry (presence of surface OH groups and surface non-stoichiometry) and to its nanocrystalline nature, which promotes the formation of crystal defects on which the decomposition of organophosphates proceeds through a nucleophilic substitution mechanism that is not dissimilar to the mechanism of enzymatic hydrolysis of organic phosphates by phosphotriesterase. PMID:26561750

  6. Chemical defense collective protection technology. Volume 12. A procedure for recharging self-contained breathing apparatus air bottles in the presence of simulated chemical warfare agents. Final report, 6-11 September 1990

    SciTech Connect

    Conkle, J.P.; Tucker, D.M.; Moore, G.

    1993-05-01

    A procedure was developed and tested for recharging Self-Contained Breathing Apparatus (SCBA) cylinders in an atmosphere contaminated with chemical agent simulant at concentrations which would produce casualties if actual agent were used. With the exception of a rack for storing the cylinders before and after recharging, all items used are currently available commercially or through off-the-shelf DOD supply sources. Cylinders were successfully recharged without contamination in the presence of chemical agent simulant in the compressor area as well as in the cylinder filling area. Inexperienced personnel easily learned and successfully followed the recharging procedures even though they were burdened by protective clothing and equipment. Chemical agents, SCBA, Firefighting, Self-contained breathing apparatus.

  7. Physical and chemical methods for enhancing rapid detection of viruses and other agents.

    PubMed Central

    Hughes, J H

    1993-01-01

    Viral replication events can be enhanced by physical, chemical, or heat treatment of cells. The centrifugation of cells can stimulate them to proliferate, reduce their generation times, and activate gene expression. Human endothelial cells can be activated to release cyclo-oxygenase metabolites after rocking for 5 min, and mechanical stress can stimulate endothelial cells to proliferate. Centrifugation of virus-infected cultures can increase cytopathic effects (CPE), enhance the number of infected cells, increase viral yields, and reduce viral detection times and may increase viral isolation rates. The rolling of virus-infected cells also has an effect similar to that of centrifugation. The continuous rolling of virus-infected cultures at < or = 2.0 rpm can enhance enterovirus, rhinovirus, reovirus, rotavirus, paramyxovirus, herpesvirus, and vaccinia virus CPE or yields or both. For some viruses, the continuous rolling of infected cell cultures at 96 rpm (1.9 x g) is superior to rolling at 2.0 rpm for viral replication or CPE production. In addition to centrifugation and rolling, the treatment of cells with chemicals or heat can also enhance viral yields or CPE. For example, the treatment of virus-infected cells with dimethyl sulfoxide can enhance viral transformation, increase plaque numbers and plaque size, increase the number of cells producing antigens, and increase viral yields. The infectivity of fowl plague virus is increased by 80-fold when 4% dimethyl sulfoxide is added to culture medium immediately after infection. The heat shocking of virus-infected cells also has been shown to have a stimulatory effect on the replication events of cytomegalovirus, Epstein-Barr virus, and human immunodeficiency virus. The effects of motion, chemicals, or heat treatments on viral replication are not well understood. These treatments apparently activate cells to make them more permissive to viral infection and viral replication. Perhaps heat shock proteins or stress

  8. Improved actuation strain of PDMS-based DEA materials chemically modified with softening agents

    NASA Astrophysics Data System (ADS)

    Biedermann, Miriam; Blümke, Martin; Wegener, Michael; Krüger, Hartmut

    2015-04-01

    Dielectric elastomer actuators (DEAs) are smart materials that gained much in interest particularly in recent years. One active field of research is the improvement of their properties by modification of their structural framework. The object of this work is to improve the actuation properties of polydimethylsiloxane (PDMS)-based DEAs by covalent incorporation of mono-vinyl-terminated low-molecular PDMS chains into the PDMS network. These low-molecular units act as a kind of softener within the PDMS network. The loose chain ends interfere with the network formation and lower the network's density. PDMS films with up to 50wt% of low-molecular PDMS additives were manufactured and the chemical, mechanical, electrical, and electromechanical properties of these novel materials were investigated.

  9. Crucial steps to life: From chemical reactions to code using agents.

    PubMed

    Witzany, Guenther

    2016-02-01

    The concepts of the origin of the genetic code and the definitions of life changed dramatically after the RNA world hypothesis. Main narratives in molecular biology and genetics such as the "central dogma," "one gene one protein" and "non-coding DNA is junk" were falsified meanwhile. RNA moved from the transition intermediate molecule into centre stage. Additionally the abundance of empirical data concerning non-random genetic change operators such as the variety of mobile genetic elements, persistent viruses and defectives do not fit with the dominant narrative of error replication events (mutations) as being the main driving forces creating genetic novelty and diversity. The reductionistic and mechanistic views on physico-chemical properties of the genetic code are no longer convincing as appropriate descriptions of the abundance of non-random genetic content operators which are active in natural genetic engineering and natural genome editing. PMID:26723230

  10. Gallic Acid as a Complexing Agent for Copper Chemical Mechanical Polishing Slurries at Neutral pH

    NASA Astrophysics Data System (ADS)

    Kim, Yung Jun; Kang, Min Cheol; Kwon, Oh Joong; Kim, Jae Jeong

    2011-05-01

    Gallic acid was investigated as a new complexing agent for copper (Cu) chemical mechanical polishing slurries at neutral pH. Addition of 0.03 M gallic acid and 1.12 M H2O2 at pH 7 resulted in a Cu removal rate of 560.73±17.49 nm/min, and the ratio of the Cu removal rate to the Cu dissolution rate was 14.8. Addition of gallic acid improved the slurry performance compared to glycine addition. X-ray photoelectron spectroscopy analysis and contact angle measurements showed that addition of gallic acid enhanced the Cu polishing behavior by suppressing the formation of surface Cu oxide.

  11. Evaluation of sperm tests as indicators of germ-cell damage in men exposed to chemical or physical agents

    SciTech Connect

    Wyrobek, A.J.; Watchmaker, G.; Gordon, L.

    1983-06-15

    As reviewed here, at least 89 chemical exposures have been studied for their effects on human spermatogenesis using sperm tests, with the majority showing some effect on sperm count, motility, or morphology. Approximately 85% of these exposures were to experimental or therapeutic drugs, 10% to occupational or environmental agents, and 5% to recreational drugs. This paper briefly describes the more common sperm-based methods and reviews some of their applications. It also includes guidelines for undertaking a human sperm study, as well as a discussion of the predictive value of induced sperm changes, an evaluation of the role of animal sperm tests, and a summary of the advantages and disadvantages of the sperm tests.

  12. Rapid screening of N-oxides of chemical warfare agents degradation products by ESI-tandem mass spectrometry.

    PubMed

    Sridhar, L; Karthikraj, R; Lakshmi, V V S; Raju, N Prasada; Prabhakar, S

    2014-08-01

    Rapid detection and identification of chemical warfare agents and related precursors/degradation products in various environmental matrices is of paramount importance for verification of standards set by the chemical weapons convention (CWC). Nitrogen mustards, N,N-dialkylaminoethyl-2-chlorides, N,N-dialkylaminoethanols, N-alkyldiethanolamines, and triethanolamine, which are listed CWC scheduled chemicals, are prone to undergo N-oxidation in environmental matrices or during decontamination process. Thus, screening of the oxidized products of these compounds is also an important task in the verification process because the presence of these products reveals alleged use of nitrogen mustards or precursors of VX compounds. The N-oxides of aminoethanols and aminoethylchlorides easily produce [M + H](+) ions under electrospray ionization conditions, and their collision-induced dissociation spectra include a specific neutral loss of 48 u (OH + CH2OH) and 66 u (OH + CH2Cl), respectively. Based on this specific fragmentation, a rapid screening method was developed for screening of the N-oxides by applying neutral loss scan technique. The method was validated and the applicability of the method was demonstrated by analyzing positive and negative samples. The method was useful in the detection of N-oxides of aminoethanols and aminoethylchlorides in environmental matrices at trace levels (LOD, up to 500 ppb), even in the presence of complex masking agents, without the use of time-consuming sample preparation methods and chromatographic steps. This method is advantageous for the off-site verification program and also for participation in official proficiency tests conducted by the Organization for the Prohibition of Chemical Weapons (OPCW), the Netherlands. The structure of N-oxides can be confirmed by the MS/MS experiments on the detected peaks. A liquid chromatography-mass spectrometry (LC-MS) method was developed for the separation of isomeric N-oxides of aminoethanols and

  13. The effect of different chemical and physical agents on the viability of Cysticercus bovis: a preliminary report.

    PubMed

    Ghebrekidan, H

    1992-01-01

    The in vitro comparative effect of 23 chemicals and 5 physical agents on the viability of Cysticerci of Taenia saginata was investigated. Accordingly the effects of Vinegar, "Kosso-Araki", "Senafitch", "Dagim-Araki", "Datta", Gin, Lemon-juice, Cognac, Fernet Whisky, Bitter, Brandy, Kilikil, "Feto", ArakiUzo, Araki-Double Uzo, Vermouth, Metta Beer, Pilsner Beer, "Awazie", "Tella", "Tej", and Sarris Wine Red and White; was assessed on the basis of minimum exposure time (in minutes) required to render viable cysticerci nonevaginable, and was found to be 5, 20, 20, 25, 40, 40, 45, 50, 55, 75, 80, 90, 90, 90, 105, 105, 110 respectively with the remaining showing no deleterious effects on the cysts up to 180 minutes of exposure. Similarly, viable bovine cysticerci were subjected to the physical forces of x-ray radiation, electricity, UV light radiation, centrifugation and vibration, and the effect of the individual agent on the cysts was assessed on the basis of minimum applicable force required to render bovine cysticerci non-evaginable. And it was found that, whereas 500 grays (Gy) of absorbed xray radiation dose and electric current measuring 0.1 mA applied for 1/2 a minute were required to render cysts nonviable. A relative decrease in evagination time and increased viger and motility of the evaginated cysticerci was observed with the other physical forces. On the basis of these results, it is suggested that an attempt to understand the mechanism of action and may be elucidation of the active principle of the more potent agents will be a step forward towards a successful break in the life cycle of the parasite. PMID:1563360

  14. A Cu(II)2 Paramagnetic Chemical Exchange Saturation Transfer Contrast Agent Enabled by Magnetic Exchange Coupling.

    PubMed

    Du, Kang; Harris, T David

    2016-06-29

    The ability of magnetic exchange coupling to enable observation of paramagnetic chemical exchange saturation transfer (PARACEST) in transition metal ions with long electronic relaxation times (τs) is demonstrated. Metalation of the dinucleating, tetra(carboxamide) ligand HL with Cu(2+) in the presence of pyrophosphate (P2O7)(4-) affords the complex [LCu(II)2(P2O7)](-). Solution-phase variable-temperature magnetic susceptibility data reveal weak ferromagnetic superexchange coupling between the two S = 1/2 Cu(II) centers, with a coupling constant of J = +2.69(5) cm(-1), to give an S = 1 ground state. This coupling results in a sharpened NMR line width relative to a GaCu analogue, indicative of a shortening of τs. Presaturation of the amide protons in the Cu2 complex at 37 °C leads to a 14% intensity decrease in the bulk water (1)H NMR signal through the CEST effect. Conversely, no CEST effect is observed in the GaCu complex. These results provide the first example of a Cu-based PARACEST magnetic resonance contrast agent and demonstrate the potential to expand the metal ion toolbox for PARACEST agents through introduction of magnetic exchange coupling. PMID:27276533

  15. Broad-Spectrum Liquid- and Gas-Phase Decontamination of Chemical Warfare Agents by One-Dimensional Heteropolyniobates.

    PubMed

    Guo, Weiwei; Lv, Hongjin; Sullivan, Kevin P; Gordon, Wesley O; Balboa, Alex; Wagner, George W; Musaev, Djamaladdin G; Bacsa, John; Hill, Craig L

    2016-06-20

    A wide range of chemical warfare agents and their simulants are catalytically decontaminated by a new one-dimensional polymeric polyniobate (P-PONb), K12 [Ti2 O2 ][GeNb12 O40 ]⋅19 H2 O (KGeNb) under mild conditions and in the dark. Uniquely, KGeNb facilitates hydrolysis of nerve agents Sarin (GB) and Soman (GD) (and their less reactive simulants, dimethyl methylphosphonate (DMMP)) as well as mustard (HD) in both liquid and gas phases at ambient temperature and in the absence of neutralizing bases or illumination. Three lines of evidence establish that KGeNb removes DMMP, and thus likely GB/GD, by general base catalysis: a) the k(H2 O)/k(D2 O) solvent isotope effect is 1.4; b) the rate law (hydrolysis at the same pH depends on the amount of P-PONb present); and c) hydroxide is far less active against the above simulants at the same pH than the P-PONbs themselves, a critical control experiment. PMID:27061963

  16. Continuum Model for Decontamination of Chemical Warfare Agent from a Rubbery Polymer using the Maxwell-Stefan Formulation

    NASA Astrophysics Data System (ADS)

    Varady, Mark; Bringuier, Stefan; Pearl, Thomas; Stevenson, Shawn; Mantooth, Brent

    Decontamination of polymers exposed to chemical warfare agents (CWA) often proceeds by application of a liquid solution. Absorption of some decontaminant components proceed concurrently with extraction of the CWA, resulting in multicomponent diffusion in the polymer. In this work, the Maxwell-Stefan equations were used with the Flory-Huggins model of species activity to mathematically describe the transport of two species within a polymer. This model was used to predict the extraction of the nerve agent O-ethyl S-[2(diisopropylamino)ethyl] methylphosphonothioate (VX) from a silicone elastomer into both water and methanol. Comparisons with experimental results show good agreement with minimal fitting of model parameters from pure component uptake data. Reaction of the extracted VX with sodium hydroxide in the liquid-phase was also modeled and used to predict the overall rate of destruction of VX. Although the reaction proceeds more slowly in the methanol-based solution compared to the aqueous solution, the extraction rate is faster due to increasing VX mobility as methanol absorbs into the silicone, resulting in an overall faster rate of VX destruction.

  17. A two-pulse, pump-probe method for short-range, remote standoff detection of chemical warfare agents

    NASA Astrophysics Data System (ADS)

    Bisson, Scott E.; Headrick, Jeffrey M.; Reichardt, Thomas A.; Farrow, Roger L.; Kulp, Thomas J.

    2011-05-01

    We describe a photofragment laser-induced fluorescence (PF-LIF) method that can be applied to the short-range-standoff detection of low-volatility organophosphonate chemical warfare agents (OP-CWAs) on surfaces. It operates by photofragmenting a surface-bound analyte and then actively interrogating a released phosphorous monoxide (PO) fragment using LIF. We demonstrate a single-pulse-pair (pump = 500 μJ @ 266 nm; probe = 20 μJ @ 248 nm) surface detection sensitivity of 30 μg/cm2 for the organophosphonate diisopropyl isothiocyanate phosphonate (DIPP) on aluminum and 210 μg/cm2 for the same analyte on a more porous concrete surface. By detecting the PO photofragment, the method indicates the presence of organophosphonates; however, we show that it also responds to other phosphorouscontaining compounds. Because of its limited specificity, we believe that the method may have most immediate use as a mapping tool to rapidly identify "hotspots" of OP-CWAs. These would then be confirmed using a more specific tool. As one method of confirming the presence of OP-CWAs (and identifying the agent), we demonstrate that the probe beam can be used to acquire Raman-scattering spectra of the target area.

  18. Amino resin modified xanthan polymer foamed with a chemical blowing agent

    SciTech Connect

    Hazlett, R.D.; Shu, P.

    1989-05-16

    A method is described for reducing the permeability in an area of a subterranean formation which consists of mixing a gellable composition containing: water, about 0.2 to about 5.0 wt.% of a cross linkable polysaccharide biopolymer having at least one functional group charide biopolymer having at least one functional group selected from a member of the group consisting of an amine, an amide, a hydroxyl, or a thiol group, and about 0.02 to about 5.0 wt.% of an aminoplast resin which reinforces the biopolymer thereby causing the polymer to become more thermally stable. Also included are sufficient transitional metal ions to form a gel of a size and strength sufficient to reduce permeability in a more permeable zone in the formation. A chemical surfactant, and an alkali metal salt of azodicarboxylic acid, are then introduced produce a gas sufficient to foam the composition described above. The composition is then injected into the desired area of the formation where the azodicarboxylic acid decomposes thereby generating nitrogen and carbon dioxide gas in an amount sufficient to form a foam which subsequently hardens and reduces the permeability in the desired area.

  19. Chemical composition and biological evaluation of Physalis peruviana root as hepato-renal protective agent.

    PubMed

    El-Gengaihi, Souad E; Hassan, Emad E; Hamed, Manal A; Zahran, Hanan G; Mohammed, Mona A

    2013-03-01

    This study was designed to investigate the potential of Physalis peruviana root as a functional food with hepato-renal protective effects against fibrosis. The chemical composition of the plant root suggested the presence of alkaloids, withanolides and flavonoids. Five compounds were isolated and their structures elucidated by different spectral analysis techniques. One compound was isolated from the roots: cuscohygrine. The biological evaluation was conducted on different animal groups; control rats, control treated with ethanolic root extract, CCl(4) group, CCl(4) treated with root extract, and CCl(4) treated with silymarin as a standard herbal drug. The evaluation used the oxidative stress markers malondialdehyde (MDA), superoxide dismutase (SOD), and nitric oxide (NO). The liver function indices; aspartate and alanine aminotransferases (AST & ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), bilirubin, and total hepatic protein were also estimated. Kidney disorder biomarkers; creatinine, urea, and serum protein were also evaluated. The results suggested safe administration, and improvement of all the investigated parameters. The liver and kidney histopathological analysis confirmed the results. In conclusion, P. peruviana succeeded in protecting the liver and kidney against fibrosis. Further studies are needed to discern their pharmacological applications and clinical uses. PMID:23419022

  20. On modeling of chemical stimulation of an enhanced geothermal system using a high pH solution with chelating agent

    SciTech Connect

    Xu, T.; Rose, P.; Fayer, S.; Pruess, K.

    2009-05-01

    Dissolution of silica and calcite in the presence of a chelating agent (NTA) at a high pH was successfully demonstrated in laboratory experiments using a high-temperature flow reactor. (Note that the term 'silica' used here includes amorphous silica, quartz, and silicate glass bead). The mineral dissolution and associated porosity enhancement in the experiments were reproduced by reactive transport modeling using TOUGHREACT. The chemical stimulation method was applied by numerical modeling to a field geothermal injection well system to investigate its effectiveness. Parameters applicable to the quartz monzodiorite unit at the Enhanced Geothermal Systems (EGS) site at Desert Peak (Nevada) were used. Results indicate that the injection of a high pH chelating solution results in dissolution of both calcite and plagioclase, while avoiding precipitation of calcite at high temperature conditions. Consequently reservoir porosity and permeability can be enhanced especially near the injection well. Injection at a lower temperature of 120 C (over 160 C in the base-case) results in a porosity increase that is smaller close to the injection point, but extends to a larger radial distance. A slower kinetic rate results in less aggressive mineral dissolution close to the injection point and larger extent along the flow path, which is favorable for chemical stimulation.

  1. Mechanistic insights into the luminescent sensing of organophosphorus chemical warfare agents and simulants using trivalent lanthanide complexes.

    PubMed

    Dennison, Genevieve H; Johnston, Martin R

    2015-04-20

    Organophosphorus chemical warfare agents (OP CWAs) are potent acetylcholinesterase inhibitors that can cause incapacitation and death within minutes of exposure, and furthermore are largely undetectable by the human senses. Fast, efficient, sensitive and selective detection of these compounds is therefore critical to minimise exposure. Traditional molecular-based sensing approaches have exploited the chemical reactivity of the OP CWAs, whereas more recently supramolecular-based approaches using non-covalent interactions have gained momentum. This is due, in part, to the potential development of sensors with second-generation properties, such as reversibility and multifunction capabilities. Supramolecular sensors also offer opportunities for incorporation of metal ions allowing for the exploitation of their unique properties. In particular, trivalent lanthanide ions are being increasingly used in the OP CWA sensing event and their use in supramolecular sensors is discussed in this Minireview. We focus on the fundamental interactions of simple lanthanide systems with OP CWAs and simulants, along with the development of more elaborate and complex systems including those containing nanotubes, polymers and gold nanoparticles. Whilst literature investigations into lanthanide-based OP CWA detection systems are relatively scarce, their unique and versatile properties provide a promising platform for the development of more efficient and complex sensing systems into the future. PMID:25649522

  2. Concise and Efficient Fluorescent Probe via an Intromolecular Charge Transfer for the Chemical Warfare Agent Mimic Diethylchlorophosphate Vapor Detection.

    PubMed

    Yao, Junjun; Fu, Yanyan; Xu, Wei; Fan, Tianchi; Gao, Yixun; He, Qingguo; Zhu, Defeng; Cao, Huimin; Cheng, Jiangong

    2016-02-16

    Sarin, used as chemical warfare agents (CWAs) for terrorist attacks, can induce a number of virulent effects. Therefore, countermeasures which could realize robust and convenient detection of sarin are in exigent need. A concise charge-transfer colorimetric and fluorescent probe (4-(6-(tert-butyl)pyridine-2-yl)-N,N-diphenylaniline, TBPY-TPA) that could be capable of real-time and on-site monitoring of DCP vapor was reported in this contribution. Upon contact with DCP, the emission band red-shifted from 410 to 522 nm upon exposure to DCP vapor. And the quenching rate of TBPY-TPA reached up to 98% within 25 s. Chemical substances such as acetic acid (HAc), dimethyl methylphosphonate (DMMP), pinacolyl methylphosphonate (PAMP), and triethyl phosphate (TEP) do not interfere with the detection. A detection limit for DCP down to 2.6 ppb level is remarkably achieved which is below the Immediately Dangerous to Life or Health concentration. NMR data suggested that a transformation of the pyridine group into pyridinium salt via a cascade reaction is responsible for the sensing process which induced the dramatic fluorescent red shift. All of these data suggest TBPY-TPA is a promising fluorescent sensor for a rapid, simple, and low-cost method for DCP detection, which could be easy to prepare as a portable chemosensor kit for its practical application in real-time and on-site monitoring. PMID:26776457

  3. Disposal of chemical agents and munitions stored at Pueblo Depot Activity, Colorado. Final, Phase 1: Environmental report

    SciTech Connect

    Terry, J.W.; Blasing, T.J.; Ensminger, J.T.; Johnson, R.O.; Schexnayder, S.M.; Shor, J.T.; Staub, W.P.; Tolbert, V.R.; Zimmerman, G.P.

    1995-04-01

    Under the Chemical Stockpile Disposal Program (CSDP), the US Army proposes to dispose of lethal chemical agents and munitions stored at eight existing Army installations in the continental United States. In 1988, the US Army issued the final programmatic environmental impact statement (FPEIS) for the CSDP. The FPEIS and the subsequent Record of Decision (ROD) identified an on-site disposal process as the preferred method for destruction of the stockpile. That is, the FPEIS determined the environmentally preferred alternative to be on-site disposal in high-temperature incinerators, while the ROD selected this alternative for implementation as the preferred method for destruction of the stockpile. In this Phase I report, the overall CSDP decision regarding disposal of the PUDA Stockpile is subjected to further analyses, and its validity at PUDA is reviewed with newer, more detailed data than those providing the basis for the conclusions in the FPEIS. The findings of this Phase I report will be factored into the scope of a site-specific environmental impact statement to be prepared for the destruction of the PUDA stockpile. The focus of this Phase I report is on those data identified as having the potential to alter the Army`s previous decision regarding disposal of the PUDA stockpile; however, several other factors beyond the scope of this Phase I report must also be acknowledged to have the potential to change or modify the Army`s decisions regarding PUDA.

  4. Application of Ni-63 photo and corona discharge ionization for the analysis of chemical warfare agents and toxic wastes

    NASA Technical Reports Server (NTRS)

    Stach, J.; Adler, J.; Brodacki, M.; Doring, H.-R.

    1995-01-01

    Over the past decade, advances in instrumental design and refinements in the understanding of ion molecule reactions at atmospheric pressure enabled the application of Ion Mobility Spectrometry (IMS) as a simple inexpensive and sensitive analytical method for the detection of organic trace compounds. Positive and negative gas-phase ions for ion mobility spectrometry have been produced by a variety of methods, including photo-ionization, laser multi photon ionization, surface ionization, corona discharge ionization. The most common ion source used in ion mobility spectrometry is a radioactive Ni-63 foil which is favored due to simplicity, stability, convenience, and high selectivity. If reactant ions like (H2O(n)H)(+) or (H2O(n)O2)(-) dominate in the reaction region, nearly all kinds of compounds with a given proton or electron affinity; are ionized. However, the radioactivity of the Ni-63 foil is one disadvantage of this ion source that stimulates the development and application of other ionization techniques. In this paper, we report analyses of old chemical warfare agents and toxic wastes using Bruker RAID ion mobility spectrometers. Due to the modular construction of the measuring cell, the spectrometers can be equipped with different ion sources. The combined use of Ni-63, photo- and corona discharge ionization allows the identification of different classes of chemical compounds and yields in most cases comparable results.

  5. Behavioral, biological, and chemical perspectives on atypical agents targeting the dopamine transporterɸ

    PubMed Central

    Reith, Maarten E.A.; Blough, Bruce E.; Hong, Weimin C.; Jones, Kymry T.; Schmitt, Kyle C.; Baumann, Michael H.; Partilla, John S.; Rothman, Richard B.; Katz, Jonathan L.

    2014-01-01

    Background Treatment of Stimulant-Use Disorders remains a formidable challenge, and the dopamine transporter (DAT) remains a potential target for antagonist or agonist-like substitution therapies. Methods This review focuses on DAT ligands, such as benztropine, GBR 12909, modafinil, and DAT substrates derived from phenethylamine or cathinone that have atypical DAT-inhibitor effects, either in vitro or in vivo. The compounds are described from a molecular mechanistic, behavioral, and medicinal-chemical perspective. Results Possible mechanisms for atypicality at the molecular level can be deduced from the conformational cycle for substrate translocation. For each conformation, a crystal structure of a bacterial homolog is available, with a possible role of cholesterol, which is also present in the crystal of drosophila DAT. Although there is a direct relationship between behavioral potencies of most DAT inhibitors and their DAT affinities, a number of compounds bind to the DAT and inhibit dopamine uptake but do not share cocaine-like effects. Such atypical behavior, depending on the compound, may be related to slow DAT association, combined sigma-receptor actions, or bias for cytosol-facing DAT. Some structures are sterically small enough to serve as DAT substrates but large enough to also inhibit transport. Such compounds may display partial DA releasing effects, and may be combined with release or uptake inhibition at other monoamine transporters. Conclusions Mechanisms of atypical DAT inhibitors may serve as targets for the development of treatments for stimulant abuse. These mechanisms are novel and their further exploration may produce compounds with unique therapeutic potential as treatments for stimulant abuse. PMID:25548026

  6. Computational Investigations of Potential Energy Function Development for Metal--Organic Framework Simulations, Metal Carbenes, and Chemical Warfare Agents

    NASA Astrophysics Data System (ADS)

    Cioce, Christian R.

    sigma donates, and subsequent back-bonding occurs into a pi* antibonding orbital. This is a different type of interaction not seen in the three existing classes of metal-carbene complexes, namely Fischer, Schrock, and Grubbs. Finally, the virtual engineering of enhanced chemical warfare agent (CWA) detection systems is discussed. As part of a U.S. Department of Defense supported research project, in silico chemical modifications to a previously synthesized zinc-porphyrin, ZnCS1, were made to attempt to achieve preferential binding of the nerve agent sarin versus its simulant, DIMP (diisopropyl methylphosphonate). Upon modification, a combination of steric effects and induced hydrogen bonding allowed for the selective binding of sarin. The success of this work demonstrates the role that high performance computing can play in national security research, without the associated costs and high security required for experimentation.

  7. Acute environmental toxicity and persistence of DEM, a chemical agent simulant: Diethyl malonate. [Diethyl malonate

    SciTech Connect

    Cataldo, D.A.; Ligotke, M.W.; Harvey, S.D.; Fellows, R.J.; Li, Shu-mei W.; Van Voris, P.; Wentsel, R.S.

    1990-05-01

    The purpose of the following chemical simulant studies is to assess the potential acute environmental effects and persistence of diethyl malonate (DEM). Deposition velocities for DEM to soil surfaces ranged from 0.04 to 0.2 cm/sec. For foliar surfaces, deposition velocities ranged from 0.0002 cm/sec at low air concentrations to 0.05 cm/sec for high dose levels. The residence times or half-lives of DEM deposited to soils was 2 h for the fast component and 5 to 16 h for the residual material. DEM deposited to foliar surfaces also exhibited biphasic depuration. The half-life of the short residence time component ranged from 1 to 3 h, while the longer time component had half-times of 16 to 242 h. Volatilization and other depuration mechanisms reduce surface contaminant levels in both soils and foliage to less than 1% of initial dose within 96 h. DEM is not phytotoxic at foliar mass loading levels of less than 10 {mu}m/cm{sup 2}. However, severe damage is evident at mass loading levels in excess of 17 {mu}g/cm{sup 2}. Tall fescue and sagebrush were more affected than was short-needle pine, however, mass loading levels were markedly different. Regrowth of tall fescue indicated that the effects of DEM are residual, and growth rates are affected only at higher mass loadings through the second harvest. Results from in vitro testing of DEM indicated concentrations below 500 {mu}g/g dry soil generally did not negatively impact soil microbial activity. Short-term effects of DEM were more profound on soil dehydrogenase activity than on soil phosphatase activity. No enzyme inhibition or enhancement was observed after 28 days in incubation. Results of the earthworm bioassay indicate survival to be 86 and 66% at soil doses of 107 and 204 {mu}g DEM/cm{sup 2}, respectively. At higher dose level, activity or mobility was judged to be affected in over 50% of the individuals. 21 refs., 10 figs., 15 tabs.

  8. De Novo Assembly and Transcriptome Analysis of Wheat with Male Sterility Induced by the Chemical Hybridizing Agent SQ-1

    PubMed Central

    Zhang, Gaisheng; Ju, Lan; Zhang, Jiao; Yu, Yongang; Niu, Na; Wang, Junwei; Ma, Shoucai

    2015-01-01

    Wheat (Triticum aestivum L.), one of the world’s most important food crops, is a strictly autogamous (self-pollinating) species with exclusively perfect flowers. Male sterility induced by chemical hybridizing agents has increasingly attracted attention as a tool for hybrid seed production in wheat; however, the molecular mechanisms of male sterility induced by the agent SQ-1 remain poorly understood due to limited whole transcriptome data. Therefore, a comparative analysis of wheat anther transcriptomes for male fertile wheat and SQ-1–induced male sterile wheat was carried out using next-generation sequencing technology. In all, 42,634,123 sequence reads were generated and were assembled into 82,356 high-quality unigenes with an average length of 724 bp. Of these, 1,088 unigenes were significantly differentially expressed in the fertile and sterile wheat anthers, including 643 up-regulated unigenes and 445 down-regulated unigenes. The differentially expressed unigenes with functional annotations were mapped onto 60 pathways using the Kyoto Encyclopedia of Genes and Genomes database. They were mainly involved in coding for the components of ribosomes, photosynthesis, respiration, purine and pyrimidine metabolism, amino acid metabolism, glutathione metabolism, RNA transport and signal transduction, reactive oxygen species metabolism, mRNA surveillance pathways, protein processing in the endoplasmic reticulum, protein export, and ubiquitin-mediated proteolysis. This study is the first to provide a systematic overview comparing wheat anther transcriptomes of male fertile wheat with those of SQ-1–induced male sterile wheat and is a valuable source of data for future research in SQ-1–induced wheat male sterility. PMID:25898130

  9. De Novo Assembly and Transcriptome Analysis of Wheat with Male Sterility Induced by the Chemical Hybridizing Agent SQ-1.

    PubMed

    Zhu, Qidi; Song, Yulong; Zhang, Gaisheng; Ju, Lan; Zhang, Jiao; Yu, Yongang; Niu, Na; Wang, Junwei; Ma, Shoucai

    2015-01-01

    Wheat (Triticum aestivum L.), one of the world's most important food crops, is a strictly autogamous (self-pollinating) species with exclusively perfect flowers. Male sterility induced by chemical hybridizing agents has increasingly attracted attention as a tool for hybrid seed production in wheat; however, the molecular mechanisms of male sterility induced by the agent SQ-1 remain poorly understood due to limited whole transcriptome data. Therefore, a comparative analysis of wheat anther transcriptomes for male fertile wheat and SQ-1-induced male sterile wheat was carried out using next-generation sequencing technology. In all, 42,634,123 sequence reads were generated and were assembled into 82,356 high-quality unigenes with an average length of 724 bp. Of these, 1,088 unigenes were significantly differentially expressed in the fertile and sterile wheat anthers, including 643 up-regulated unigenes and 445 down-regulated unigenes. The differentially expressed unigenes with functional annotations were mapped onto 60 pathways using the Kyoto Encyclopedia of Genes and Genomes database. They were mainly involved in coding for the components of ribosomes, photosynthesis, respiration, purine and pyrimidine metabolism, amino acid metabolism, glutathione metabolism, RNA transport and signal transduction, reactive oxygen species metabolism, mRNA surveillance pathways, protein processing in the endoplasmic reticulum, protein export, and ubiquitin-mediated proteolysis. This study is the first to provide a systematic overview comparing wheat anther transcriptomes of male fertile wheat with those of SQ-1-induced male sterile wheat and is a valuable source of data for future research in SQ-1-induced wheat male sterility. PMID:25898130

  10. Comparison of 6-thioguanine-resistant mutation and sister chromatid exchanges in Chinese hamster V79 cells with forty chemical and physical agents

    SciTech Connect

    Nishi, Y.; Hasegawa, M.M.; Taketomi, M.; Ohkawa, Y.; Inui, N.

    1984-08-01

    The induction of sister chromatid exchanges (SCE) and mutation at the hypoxanthine-guanine phosphoribosyl transferase locus and toxicities of 40 different chemical and physical agents were examined on Chinese hamster V79 cells. These agents included mono-, di-, tri-, and polyfunctional alkylating agents, intercalators, gamma-rays, and UV light irradiation. Mutation was measured as resistance to 6-thioguanine and toxicity as loss of cell-plating efficiency. SCE were examined 29 hr after treatment. With the agents examined, a highly positive correlation existed between SCE-inducing and mutagenic potencies, when expressed as increase in the number per a unit dose over the control values. But the great difference of the ratios of mutagenic potencies versus SCE-inducing potencies among agents was observed, the maximal difference in the ratios being about 200-fold. The agents that showed the higher values of the ratio (agents producing more mutations than SCE) were bleomycin, cobalt-60 gamma-rays, all ethylating agents (N-ethyl-N-nitrosourea, N-ethyl-N'-nitro-N-nitrosoguanidine, ethyl methanesulfonate, and diethylsulfate), N-propyl-N-nitrosourea, N-butyl-N-nitrosourea, isopropyl methanesulfonate, intercalating acridine compounds (2-methoxy-6-chloro-9-(3-(ethyl-2-chloroethyl)aminopropylamino)-acridine X 2HCl and 2-methoxy-6-chloro-9-(3-(chloroethyl)-aminopropylamino)acridine 2HCl) and UV light at 254 nm.

  11. Analysis of chemical warfare agents in organic liquid samples with magnetic dispersive solid phase extraction and gas chromatography mass spectrometry for verification of the chemical weapons convention.

    PubMed

    Singh, Varoon; Purohit, Ajay Kumar; Chinthakindi, Sridhar; Goud, Raghavender D; Tak, Vijay; Pardasani, Deepak; Shrivastava, Anchal Roy; Dubey, Devendra Kumar

    2016-05-27

    A simple, sensitive and low temperature sample preparation method is developed for detection and identification of Chemical Warfare Agents (CWAs) and scheduled esters in organic liquid using magnetic dispersive solid phase extraction (MDSPE) followed by gas chromatography-mass spectrometry analysis. The method utilizes Iron oxide@Poly(methacrylic acid-co-ethylene glycol dimethacrylate) resin (Fe2O3@Poly(MAA-co-EGDMA)) as sorbent. Variants of these sorbents were prepared by precipitation polymerization of methacrylic acid-co-ethylene glycol dimethacrylate (MAA-co-EGDMA) onto Fe2O3 nanoparticles. Fe2O3@poly(MAA-co-EGDMA) with 20% MAA showed highest recovery of analytes. Extractions were performed with magnetic microspheres by MDSPE. Parameters affecting the extraction efficiency were studied and optimized. Under the optimized conditions, method showed linearity in the range of 0.1-3.0μgmL(-1) (r(2)=0.9966-0.9987). The repeatability and reproducibility (relative standard deviations (RSDs) %) were in the range of 4.5-7.6% and 3.4-6.2% respectively for organophosphorous esters in dodecane. Limits of detection (S/N=3/1) and limit of quantification (S/N=10/1) were found to be in the range of 0.05-0.1μgmL(-1) and 0.1-0.12μgmL(-1) respectively in SIM mode for selected analytes. The method was successfully validated and applied to the extraction and identification of targeted analytes from three different organic liquids i.e. n-hexane, dodecane and silicon oil. Recoveries ranged from 58.7 to 97.3% and 53.8 to 95.5% at 3μgmL(-1) and 1μgmL(-1) spiking concentrations. Detection of diethyl methylphosphonate (DEMP) and O-Ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX) in samples provided by the Organization for Prohibition of Chemical Weapons Proficiency Test (OPCW-PT) proved the utility of the developed method for the off-site analysis of CWC relevant chemicals. PMID:27113675

  12. Ion mobility spectrometric analysis of vaporous chemical warfare agents by the instrument with corona discharge ionization ammonia dopant ambient temperature operation.

    PubMed

    Satoh, Takafumi; Kishi, Shintaro; Nagashima, Hisayuki; Tachikawa, Masumi; Kanamori-Kataoka, Mieko; Nakagawa, Takao; Kitagawa, Nobuyoshi; Tokita, Kenichi; Yamamoto, Soichiro; Seto, Yasuo

    2015-03-20

    The ion mobility behavior of nineteen chemical warfare agents (7 nerve gases, 5 blister agents, 2 lachrymators, 2 blood agents, 3 choking agents) and related compounds including simulants (8 agents) and organic solvents (39) was comparably investigated by the ion mobility spectrometry instrument utilizing weak electric field linear drift tube with corona discharge ionization, ammonia doping, purified inner air drift flow circulation operated at ambient temperature and pressure. Three alkyl methylphosphonofluoridates, tabun, and four organophosphorus simulants gave the intense characteristic positive monomer-derived ion peaks and small dimer-derived ion peaks, and the later ion peaks were increased with the vapor concentrations. VX, RVX and tabun gave both characteristic positive monomer-derived ions and degradation product ions. Nitrogen mustards gave the intense characteristic positive ion peaks, and in addition distinctive negative ion peak appeared from HN3. Mustard gas, lewisite 1, o-chlorobenzylidenemalononitrile and 2-mercaptoethanol gave the characteristic negative ion peaks. Methylphosphonyl difluoride, 2-chloroacetophenone and 1,4-thioxane gave the characteristic ion peaks both in the positive and negative ion mode. 2-Chloroethylethylsulfide and allylisothiocyanate gave weak ion peaks. The marker ion peaks derived from two blood agents and three choking agents were very close to the reactant ion peak in negative ion mode and the respective reduced ion mobility was fluctuated. The reduced ion mobility of the CWA monomer-derived peaks were positively correlated with molecular masses among structurally similar agents such as G-type nerve gases and organophosphorus simulants; V-type nerve gases and nitrogen mustards. The slope values of the calibration plots of the peak heights of the characteristic marker ions versus the vapor concentrations are related to the detection sensitivity, and within chemical warfare agents examined the slope values for sarin, soman

  13. Development of portable mass spectrometer with electron cyclotron resonance ion source for detection of chemical warfare agents in air.

    PubMed

    Urabe, Tatsuya; Takahashi, Kazuya; Kitagawa, Michiko; Sato, Takafumi; Kondo, Tomohide; Enomoto, Shuichi; Kidera, Masanori; Seto, Yasuo

    2014-01-01

    A portable mass spectrometer with an electron cyclotron resonance ion source (miniECRIS-MS) was developed. It was used for in situ monitoring of trace amounts of chemical warfare agents (CWAs) in atmospheric air. Instrumental construction and parameters were optimized to realize a fast response, high sensitivity, and a small body size. Three types of CWAs, i.e., phosgene, mustard gas, and hydrogen cyanide were examined to check if the mass spectrometer was able to detect characteristic elements and atomic groups. From the results, it was found that CWAs were effectively ionized in the miniECRIS-MS, and their specific signals could be discerned over the background signals of air. In phosgene, the signals of the 35Cl+ and 37Cl+ ions were clearly observed with high dose-response relationships in the parts-per-billion level, which could lead to the quantitative on-site analysis of CWAs. A parts-per-million level of mustard gas, which was far lower than its lethal dosage (LCt50), was successfully detected with a high signal-stability of the plasma ion source. It was also found that the chemical forms of CWAs ionized in the plasma, i.e., monoatomic ions, fragment ions, and molecular ions, could be detected, thereby enabling the effective identification of the target CWAs. Despite the disadvantages associated with miniaturization, the overall performance (sensitivity and response time) of the miniECRIS-MS in detecting CWAs exceeded those of sector-type ECRIS-MS, showing its potential for on-site detection in the future. PMID:24211802

  14. Analysis of gaseous toxic industrial compounds and chemical warfare agent simulants by atmospheric pressure ionization mass spectrometry.

    PubMed

    Cotte-Rodríguez, Ismael; Justes, Dina R; Nanita, Sergio C; Noll, Robert J; Mulligan, Christopher C; Sanders, Nathaniel L; Cooks, R Graham

    2006-04-01

    The suitability of atmospheric pressure chemical ionization mass spectrometry as sensing instrumentation for the real-time monitoring of low levels of toxic compounds is assessed, especially with respect to public safety applications. Gaseous samples of nine toxic industrial compounds, NH3, H2S, Cl2, CS2, SO2, C2H4O, HBr, C6H6 and AsH3, and two chemical warfare agent simulants, dimethyl methylphosphonate (DMMP) and methyl salicylate (MeS), were studied. API-MS proves highly suited to this application, with speedy analysis times (<30 seconds), high sensitivity, high selectivity towards analytes, good precision, dynamic range and accuracy. Tandem MS methods were implemented in selected cases for improved selectivity, sensitivity, and limits of detection. Limits of detection in the parts-per-billion and parts-per-trillion range were achieved for this set of analytes. In all cases detection limits were well below the compounds' permissible exposure limits (PELs), even in the presence of added complex mixtures of alkanes. Linear responses, up to several orders of magnitude, were obtained over the concentration ranges studied (sub-ppb to ppm), with relative standard deviations less than 3%, regardless of the presence of alkane interferents. Receiver operating characteristic (ROC) curves are presented to show the performance trade-off between sensitivity, probability of correct detection, and false positive rate. A dynamic sample preparation system for the production of gas phase analyte concentrations ranging from 100 pptr to 100 ppm and capable of admixing gaseous matrix compounds and control of relative humidity and temperature is also described. PMID:16568176

  15. Development of haemostatic decontaminants for the treatment of wounds contaminated with chemical warfare agents. 2: evaluation of in vitro topical decontamination efficacy using undamaged skin.

    PubMed

    Dalton, Christopher H; Hall, Charlotte A; Lydon, Helen L; Chipman, J K; Graham, John S; Jenner, John; Chilcott, Robert P

    2015-05-01

    The risk of penetrating, traumatic injury occurring in a chemically contaminated environment cannot be discounted. Should a traumatic injury be contaminated with a chemical warfare (CW) agent, it is likely that standard haemostatic treatment options would be complicated by the need to decontaminate the wound milieu. Thus, there is a need to develop haemostatic products that can simultaneously arrest haemorrhage and decontaminate CW agents. The purpose of this study was to evaluate a number of candidate haemostats for efficacy as skin decontaminants against three CW agents (soman, VX and sulphur mustard) using an in vitro diffusion cell containing undamaged pig skin. One haemostatic product (WoundStat™) was shown to be as effective as the standard military decontaminants Fuller's earth and M291 for the decontamination of all three CW agents. The most effective haemostatic agents were powder-based and use fluid absorption as a mechanism of action to sequester CW agent (akin to the decontaminant Fuller's earth). The envisaged use of haemostatic decontaminants would be to decontaminate from within wounds and from damaged skin. Therefore, WoundStat™ should be subject to further evaluation using an in vitro model of damaged skin. PMID:25219755

  16. Cytological and comparative proteomic analyses on male sterility in Brassica napus L. induced by the chemical hybridization agent monosulphuron ester sodium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Male sterility induced by a chemical hybridization agent (CHA) is an important tool for utilizing crop heterosis. Monosulphuron ester sodium (MES), a new acetolactate synthase-inhibitor herbicide belonging to the sulphonylurea family, has been developed as an effective CHA to induce male sterility i...

  17. Binding of chemical warfare agent simulants as guests in a coordination cage: contributions to binding and a fluorescence-based response.

    PubMed

    Taylor, Christopher G P; Piper, Jerico R; Ward, Michael D

    2016-05-01

    Cubic coordination cages act as competent hosts for several alkyl phosphonates used as chemical warfare agent simulants; a range of cage/guest structures have been determined, contributions to guest binding analysed, and a fluorescent response to guest binding demonstrated. PMID:27020844

  18. THE APPLICATION OF SINGLE PARTICLE AEROSOL MASS SPECTROMETRY FOR THE DETECTION AND IDENTIFICATION OF HIGH EXPLOSIVES AND CHEMICAL WARFARE AGENTS

    SciTech Connect

    Martin, A

    2006-10-23

    Single Particle Aerosol Mass Spectrometry (SPAMS) was evaluated as a real-time detection technique for single particles of high explosives. Dual-polarity time-of-flight mass spectra were obtained for samples of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitro-1,3,5-triazinane (RDX), and pentaerythritol tetranitrate (PETN); peaks indicative of each compound were identified. Composite explosives, Comp B, Semtex 1A, and Semtex 1H were also analyzed, and peaks due to the explosive components of each sample were present in each spectrum. Mass spectral variability with laser fluence is discussed. The ability of the SPAMS system to identify explosive components in a single complex explosive particle ({approx}1 pg) without the need for consumables is demonstrated. SPAMS was also applied to the detection of Chemical Warfare Agent (CWA) simulants in the liquid and vapor phases. Liquid simulants for sarin, cyclosarin, tabun, and VX were analyzed; peaks indicative of each simulant were identified. Vapor phase CWA simulants were adsorbed onto alumina, silica, Zeolite, activated carbon, and metal powders which were directly analyzed using SPAMS. The use of metal powders as adsorbent materials was especially useful in the analysis of triethyl phosphate (TEP), a VX stimulant, which was undetectable using SPAMS in the liquid phase. The capability of SPAMS to detect high explosives and CWA simulants using one set of operational conditions is established.

  19. Facility monitoring of chemical warfare agent simulants in air using an automated, field-deployable, miniature mass spectrometer.

    PubMed

    Smith, Jonell N; Noll, Robert J; Cooks, R Graham

    2011-05-30

    Vapors of four chemical warfare agent (CWA) stimulants, 2-chloroethyl ethyl sulfide (CEES), diethyl malonate (DEM), dimethyl methylphosphonate (DMMP), and methyl salicylate (MeS), were detected, identified, and quantitated using a fully automated, field-deployable, miniature mass spectrometer. Samples were ionized using a glow discharge electron ionization (GDEI) source, and ions were mass analyzed with a cylindrical ion trap (CIT) mass analyzer. A dual-tube thermal desorption system was used to trap compounds on 50:50 Tenax TA/Carboxen 569 sorbent before their thermal release. The sample concentrations ranged from low parts per billion [ppb] to two parts per million [ppm]. Limits of detection (LODs) ranged from 0.26 to 5.0 ppb. Receiver operating characteristic (ROC) curves are presented for each analyte. A sample of CEES at low ppb concentration was combined separately with two interferents, bleach (saturated vapor) and diesel fuel exhaust (1%), as a way to explore the capability of detecting the simulant in an environmental matrix. Also investigated was a mixture of the four CWA simulants (at concentrations in air ranging from 270 to 380 ppb). Tandem mass (MS/MS) spectral data were used to identify and quantify the individual components. PMID:21504010

  20. Preliminary evaluation of military, commercial and novel skin decontamination products against a chemical warfare agent simulant (methyl salicylate).

    PubMed

    Matar, Hazem; Guerreiro, Antonio; Piletsky, Sergey A; Price, Shirley C; Chilcott, Robert P

    2016-01-01

    Rapid decontamination is vital to alleviate adverse health effects following dermal exposure to hazardous materials. There is an abundance of materials and products which can be utilised to remove hazardous materials from the skin. In this study, a total of 15 products were evaluated, 10 of which were commercial or military products and five were novel (molecular imprinted) polymers. The efficacies of these products were evaluated against a 10 µl droplet of (14)C-methyl salicylate applied to the surface of porcine skin mounted on static diffusion cells. The current UK military decontaminant (Fuller's earth) performed well, retaining 83% of the dose over 24 h and served as a benchmark to compare with the other test products. The five most effective test products were Fuller's earth (the current UK military decontaminant), Fast-Act® and three novel polymers [based on itaconic acid, 2-trifluoromethylacrylic acid and N,N-methylenebis(acrylamide)]. Five products (medical moist-free wipes, 5% FloraFree™ solution, normal baby wipes, baby wipes for sensitive skin and Diphotérine™) enhanced the dermal absorption of (14)C-methyl salicylate. Further work is required to establish the performance of the most effective products identified in this study against chemical warfare agents. PMID:26339920

  1. First Chemical Feature Based Pharmacophore Modeling of Potent Retinoidal Retinoic Acid Metabolism Blocking Agents (RAMBAs): Identification of Novel RAMBA Scaffolds

    PubMed Central

    Purushottamachar, Puranik; Patel, Jyoti B.; Gediya, Lalji K; Clement, Omoshile O.; Njar, Vincent C. O.

    2011-01-01

    The first three-dimensional (3D) pharmacophore model was developed for potent retinoidal retinoic acid metabolism blocking agents (RAMBAs) with IC50 values ranging from 0.0009 to 5.84 nM. The seven common chemical features in these RAMBAs as deduced by the Catalyst/HipHop program include five hydrophobic groups (hydrophobes), one hydrogen bond acceptor (HBA) and one ring aromatic group. Using the pharmacophore model as a 3D search query against NCI and Maybridge conformational Catalyst formatted databases; we retrieved several compounds with different structures (scaffolds) as hits. Twenty one retrieved hits were tested for RAMBA activity at 100 nM concentration. The most potent of these compounds, NCI10308597 and HTS01914 showed inhibitory potencies less (54.7% and 53.2%, respectively, at 100 nM) than those of our best previously reported RAMBAs VN/12-1 and VN/14-1 (90% and 86%, respectively, at 100 nM). Docking studies using a CYP26A1 homology model revealed that our most potent RAMBAs showed similar binding to the one observed for a series of RAMBAs reported previously by others. Our data shows the potential of our pharmacophore model in identifying structurally diverse and potent RAMBAs. Further refinement of the model and searches of other robust databases is currently in progress with a view to identifying and optimizing new leads. PMID:22130607

  2. Decomposition of 2-chloroethylethylsulfide on copper oxides to detoxify polymer-based spherical activated carbons from chemical warfare agents.

    PubMed

    Fichtner, S; Hofmann, J; Möller, A; Schrage, C; Giebelhausen, J M; Böhringer, B; Gläser, R

    2013-11-15

    For the decomposition of chemical warfare agents, a hybrid material concept was applied. This consists of a copper oxide-containing phase as a component with reactive functionality supported on polymer-based spherical activated carbon (PBSAC) as a component with adsorptive functionality. A corresponding hybrid material was prepared by impregnation of PBSAC with copper(II)nitrate and subsequent calcination at 673K. The copper phase exists predominantly as copper(I)oxide which is homogeneously distributed over the PBSAC particles. The hybrid material containing 16 wt.% copper on PBSAC is capable of self-detoxifying the mustard gas surrogate 2-chloroethylethylsulfide (CEES) at room temperature. The decomposition is related to the breakthrough behavior of the reactant CEES, which displaces the reaction product ethylvinylsulfide (EVS). This leads to a combined breakthrough of CEES and EVS. The decomposition of CEES is shown to occur catalytically over the copper-containing PBSAC material. Thus, the hybrid material can even be considered to be self-cleaning. PMID:24140529

  3. Effective, Facile, and Selective Hydrolysis of the Chemical Warfare Agent VX Using Zr6-Based Metal-Organic Frameworks.

    PubMed

    Moon, Su-Young; Wagner, George W; Mondloch, Joseph E; Peterson, Gregory W; DeCoste, Jared B; Hupp, Joseph T; Farha, Omar K

    2015-11-16

    The nerve agent VX is among the most toxic chemicals known to mankind, and robust solutions are needed to rapidly and selectively deactivate it. Herein, we demonstrate that three Zr6-based metal-organic frameworks (MOFs), namely, UiO-67, UiO-67-NH2, and UiO-67-N(Me)2, are selective and highly active catalysts for the hydrolysis of VX. Utilizing UiO-67, UiO-67-NH2, and UiO-67-N(Me)2 in a pH 10 buffered solution of N-ethylmorpholine, selective hydrolysis of the P-S bond in VX was observed. In addition, UiO-67-N(Me)2 was found to catalyze VX hydrolysis with an initial half-life of 1.8 min. This half-life is nearly 3 orders of magnitude shorter than that of the only other MOF tested to date for hydrolysis of VX and rivals the activity of the best nonenzymatic materials. Hydrolysis utilizing Zr-based MOFs is also selective and facile in the absence of pH 10 buffer (just water) and for the destruction of the toxic byproduct EA-2192. PMID:26505999

  4. Express analysis of explosives, chemical warfare agents and drugs with multicapillary column gas chromatography and ion mobility increment spectrometry.

    PubMed

    Buryakov, Igor A

    2004-02-01

    Description of a gas chromatograph designed for express analysis of explosives (2,4-dinitrotoluene, 2,4,6-trinitrotoluene, pentaerythritol tetranitrate), chemical warfare agents (mustard gas, lewisite, sarin) and drugs (heroin, cocaine hydrochloride, crack) is given. The devices comprises a multicapillary chromatographic column and an ion mobility increment spectrometer (MCC-IMIS). The main analytical characteristics of an IMIS (estimated detection limit (DL), linear dynamic range (LDR), speed of response) and a chromatographic column (separation power, degree of separation, a number of possible peaks at a chromatogram section, divided by analysis time) are determined. The maximum value of DL equal to 5 pg/ml was registered for cis-alpha-LW, and the lowest one of 0.001 pg/ml was for cocaine. The maximum value of LDR equal to 1000 was registered for sarin and the lowest one of 150 was for the ions of lewisite. Speed of response of one compound detection with the IMIS was 0.7 s. PMID:14698239

  5. Background chemistry for chemical warfare agents and decontamination processes in support of delisting waste streams at the U.S. Army Dugway Proving Ground, Utah

    SciTech Connect

    Rosenblatt, D.H.; Small, M.J.; Kimmell, T.A.; Anderson, A.W.

    1996-04-01

    The State of Utah, Department of Environmental Quality (DEQ), Division of Solid and Hazardous Waste (DSHW), has declared residues resulting from the demilitarization, treatment, cleanup, and testing of military chemical agents to be hazardous wastes. These residues have been designated as corrosive, reactive, toxic, and acute hazardous (Hazardous Waste No. F999). The RCRA regulations (40 Code of Federal Regulations [CFR] 260-280), the Utah Administrative Code (R-315), and other state hazardous waste programs list specific wastes as hazardous but allow generators to petition the regulator to {open_quotes}delist,{close_quotes} if it can be demonstrated that such wastes are not hazardous. The U.S. Army Test and Evaluation Command (TECOM) believes that certain categories of F999 residues are not hazardous and has obtained assistance from Argonne National Laboratory (Argonne) to make the delisting demonstration. The objective of this project is to delist chemical agent decontaminated residues resulting from materials testing activities and to delist a remediation residue (e.g., contaminated soil). To delist these residues, it must be demonstrated that the residues (1) do not contain hazardous quantities of the listed agents; (2) do not contain hazardous quantities of constituents listed in 40 CFR Part 261, Appendix VIII; (3) do not exhibit other characteristics that could define the residues as hazardous; and (4) do not fail a series of acute toxicity tests. The first phase will focus on a subset of the F999 wastes generated at the U.S. Army Dugway Proving Ground (DPG), where the Army tests the effects of military chemical agents and agent-decontamination procedures on numerous military items. This effort is identified as Phase I of the Delisting Program. Subsequent phases will address other DPG chemical agent decontaminated residues and remediation wastes and similar residues at other installations.

  6. Laboratory and Field Testing of Commercially Available Detectors for the Identification of Chemicals of Interest in the Nuclear Fuel Cycle for the Detection of Undeclared Activities

    SciTech Connect

    Carla Miller; Mary Adamic; Stacey Barker; Barry Siskind; Joe Brady; Warren Stern; Heidi Smartt; Mike McDaniel; Mike Stern; Rollin Lakis

    2014-07-01

    Traditionally, IAEA inspectors have focused on the detection of nuclear indicators as part of infield inspection activities. The ability to rapidly detect and identify chemical as well as nuclear signatures can increase the ability of IAEA inspectors to detect undeclared activities at a site. Identification of chemical indicators have been limited to use in the analysis of environmental samples. Although IAEA analytical laboratories are highly effective, environmental sample processing does not allow for immediate or real-time results to an IAEA inspector at a facility. During a complementary access inspection, under the Additional Protocol, the use of fieldable technologies that can quickly provide accurate information on chemicals that may be indicative of undeclared activities can increase the ability of IAEA to effectively and efficiently complete their mission. The Complementary Access Working Group (CAWG) is a multi-laboratory team with members from Brookhaven National Laboratory, Idaho National Laboratory, Los Alamos National Laboratory, and Sandia National Laboratory. The team identified chemicals at each stage of the nuclear fuel cycle that may provide IAEA inspectors with indications that proliferation activities may be occurring. The group eliminated all indicators related to equipment, technology and training, developing a list of by-products/effluents, non-nuclear materials, nuclear materials, and other observables. These proliferation indicators were prioritized based on detectability from a conduct of operations (CONOPS) perspective of a CA inspection (for example, whether an inspector actually can access the S&O or whether it is in process with no physical access), and the IAEA’s interest in the detection technology in conjunction with radiation detectors. The list was consolidated to general categories (nuclear materials from a chemical detection technique, inorganic chemicals, organic chemicals, halogens, and miscellaneous materials). The team

  7. MS Detectors

    SciTech Connect

    Koppenaal, David W.; Barinaga, Charles J.; Denton, M Bonner B.; Sperline, Roger P.; Hieftje, Gary M.; Schilling, G. D.; Andrade, Francisco J.; Barnes IV., James H.

    2005-11-01

    Good eyesight is often taken for granted, a situation that everyone appreciates once vision begins to fade with age. New eyeglasses or contact lenses are traditional ways to improve vision, but recent new technology, i.e. LASIK laser eye surgery, provides a new and exciting means for marked vision restoration and improvement. In mass spectrometry, detectors are the 'eyes' of the MS instrument. These 'eyes' have also been taken for granted. New detectors and new technologies are likewise needed to correct, improve, and extend ion detection and hence, our 'chemical vision'. The purpose of this report is to review and assess current MS detector technology and to provide a glimpse towards future detector technologies. It is hoped that the report will also serve to motivate interest, prompt ideas, and inspire new visions for ion detection research.

  8. Dermal toxicity evaluation of neutralized Chemical Agent Identification Sets (CAIS) with an overview of the dermal toxicity of vesicant agents and their degradation products. Final report, January-September 1995

    SciTech Connect

    Olajos, E.J.; Cameron, K.P.; Way, R.A.; Manthei, J.H.; Heitkamp, D.H.

    1996-10-01

    Acute dermal toxicity (limit test) and skin irritation studies were conducted in New Zealand white rabbits to ascertain the systemic toxicity and skin-injury potential of chemically-neutralized Chemical Agent Identification Sets (CAIS). Studies also included the assessment of oxidant/solvent systems and solvent induced toxicity. The toxicity limit test consisted of a 24-hr occluded exposure to 1.0 ml/kg of `test article.` Dermal irritation studies were based on a 4-hr occluded exposure to 0.5 ml of `test article.` Chemical neutralization of CAIS resulted in complex product solutions (wastestreams) containing ppm levels of agent and an array of degradation products. Findings from the skin irritation testing of wastestreams and oxidant/solvent systems indicate that wastestream-induced skin effects (edema and erythema) were equivalent to or less in severity than the skin effects produced by exposure to oxidant/solvent systems. Systemic effects were not observed in 4/5 wastestream-exposed groups; however, 2/5 wastestream-treated groups exhibited systemic effects. Lethality was noted in only 1/5 wastestream-treated groups. Limit test data indicate that agents (HD, HN, or L) were destroyed by reaction with oxidant to less toxic materials.

  9. Absorbent pads for Containment, Neutralization, and Clean-Up of Environmental Spills Containing Chemically-Reactive Agents

    NASA Technical Reports Server (NTRS)

    Davis, Dennis D. (Inventor)

    1997-01-01

    A pad for cleaning up liquid spills is described which contains a porous surface covering, and an absorbent interior containing chemically reactive reagents for neutralizing noxious chemicals within the spilled liquid. The porous surface and the absorbent component would normally consist of chemically resistant materials allowing tentative spill to pass. The absorbent interior which contains the neutralizing reagents can but is not required to be chemically resilient and conducts the liquid chemical spill towards the absorbent interior containing the chemically reactive reagents where the dangerous and undesirable chemicals within the chemical spill are then neutralized as well as removed from the premises.

  10. Cancer morbidity in British military veterans included in chemical warfare agent experiments at Porton Down: cohort study

    PubMed Central

    Linsell, L; Brooks, C; Keegan, T J; Langdon, T; Doyle, P; Maconochie, N E S; Fletcher, T; Nieuwenhuijsen, M J; Beral, V

    2009-01-01

    Objective To determine cancer morbidity in members of the armed forces who took part in tests of chemical warfare agents from 1941 to 1989. Design Historical cohort study, with cohort members followed up to December 2004. Data source Archive of UK government research facility at Porton Down, UK military personnel records, and national death and cancer records. Participants All veterans included in the cohort study of mortality, excluding those known to have died or been lost to follow-up before 1 January 1971 when the UK cancer registration system commenced: 17 013 male members of the UK armed forces who took part in tests (Porton Down veterans) and a similar group of 16 520 men who did not (non-Porton Down veterans). Main outcome measures Cancer morbidity in each group of veterans; rate ratios, with 95% confidence intervals, adjusted for age group and calendar period. Results 3457 cancers were reported in the Porton Down veterans compared with 3380 cancers in the non-Porton Down veterans. While overall cancer morbidity was the same in both groups (rate ratio 1.00, 95% confidence interval 0.95 to 1.05), Porton Down veterans had higher rates of ill defined malignant neoplasms (1.12, 1.02 to 1.22), in situ neoplasms (1.45, 1.06 to 2.00), and those of uncertain or unknown behaviour (1.32, 1.01 to 1.73). Conclusion Overall cancer morbidity in Porton Down veterans was no different from that in non-Porton Down veterans. PMID:19318700

  11. Handheld and mobile hyperspectral imaging sensors for wide-area standoff detection of explosives and chemical warfare agents

    NASA Astrophysics Data System (ADS)

    Gomer, Nathaniel R.; Gardner, Charles W.; Nelson, Matthew P.

    2016-05-01

    Hyperspectral imaging (HSI) is a valuable tool for the investigation and analysis of targets in complex background with a high degree of autonomy. HSI is beneficial for the detection of threat materials on environmental surfaces, where the concentration of the target of interest is often very low and is typically found within complex scenery. Two HSI techniques that have proven to be valuable are Raman and shortwave infrared (SWIR) HSI. Unfortunately, current generation HSI systems have numerous size, weight, and power (SWaP) limitations that make their potential integration onto a handheld or field portable platform difficult. The systems that are field-portable do so by sacrificing system performance, typically by providing an inefficient area search rate, requiring close proximity to the target for screening, and/or eliminating the potential to conduct real-time measurements. To address these shortcomings, ChemImage Sensor Systems (CISS) is developing a variety of wide-field hyperspectral imaging systems. Raman HSI sensors are being developed to overcome two obstacles present in standard Raman detection systems: slow area search rate (due to small laser spot sizes) and lack of eye-safety. SWIR HSI sensors have been integrated into mobile, robot based platforms and handheld variants for the detection of explosives and chemical warfare agents (CWAs). In addition, the fusion of these two technologies into a single system has shown the feasibility of using both techniques concurrently to provide higher probability of detection and lower false alarm rates. This paper will provide background on Raman and SWIR HSI, discuss the applications for these techniques, and provide an overview of novel CISS HSI sensors focused on sensor design and detection results.

  12. MR 714, a new aryloxypropionic non-steroidal antiinflammatory agent. Chemical and pharmacokinetic properties and preliminary pharmacotoxicological data.

    PubMed

    Marzo, A; Quadro, G; Bruno, G; Treffner, E; Reali, F L; Borrelli, G; Stradi, R

    1983-01-01

    2-(4-(2',4'-Difluorophenyl)-phenoxy)propionic acid (MR 714) is endowed with an interesting analgesic and antiinflammatory activity, while any remarkable gastro-ulcerogenic action is virtually absent. From a toxicological point of view, MR 714 orally administered to mice showed a LD50 of 848 mg/kg; an observation of general behaviour proved that the drug is free of any remarkable effect on general behaviour, food and water intake, or diuresis after single or repeated administration. An autoptic examination after single oral doses (25, 50, 100 and 200 mg/kg) or repeated oral doses (100 mg/kg/day over 5 days) did not show any adverse modification and also the Ames test didn't allow any mutagenic action to be detected. From a pharmacokinetic point of view, MR 714 given p.o. to rats was absorbed excellently and plasma levels showed a peak after 4-6 h, followed by a plateau lasting 24-36 h at a dose of 50 or 100 mg/kg and considerably less at a dosage of 25 mg/kg. This lower dose allowed a dominant half-life (t1/2) of plasma levels of 13 h to be determined. Excretion occurred only via the bile in conjugated form (acylglucuronide) which reverted easily into the parent drug. The resultant enterohepatic circulation contributes to a substantial maintenance of plasma levels and hence long-lasting activity. Among the organs examined, the uterus showed the highest ratio of organ/plasma concentration; this evidence points to a possible clinical application of MR 714 in the treatment of dysmenorrhoea. From a chemical point of view, the aryloxypropionic structure may be regarded as an interesting novelty in the field of structure-activity relationship studies on non-steroidal antiinflammatory agents. PMID:6342626

  13. Synthesis and characterization of N-acylaniline derivatives as potential chemical hybridizing agents (CHAs) for wheat (Triticum aestivum L.).

    PubMed

    Chakraborty, Kajal; Devakumar, C

    2006-09-01

    Induction of male sterility by deployment of chemical hybridizing agents (CHAs) are important in heterosis breeding of self-pollinated crops like wheat, wherein the male and female organs are in the same flower. Taking a lead from the earlier work on rice, a total of 25 N-acylanilines comprising of malonanilates, acetoacetanilides, and acetanilides (including halogenated acetanilides) were synthesized and screened as CHAs on three genotypes of wheat, viz., PBW 343, HD 2046, and HD 2733 at 1500 ppm in the winter of 2001-2002. The N-acylanilines containing variations at the acyl and aromatic domain were synthesized by condensation of substituted anilines with appropriate diesters, acid chlorides, or monoesters. The test compounds with highly electronegative groups such as F/Br at the para position of the aryl ring were identified as the most potent CHAs, causing higher induction of male sterility. A variation of N-substitution at the side chain generally furnished analogues like 4'-fluoroacetoacetanilide (7) and ethyl 4'-fluoromalonanilate (1), which induced 89.12 and 84.66% male sterility, respectively, in PBW 343. Among halogenated acetanilides, the increasing number of chlorine atoms in the side chain led to an increase in the activity of 4'-fluoro (23) and 4'-bromo (24) derivatives of trichoroacetanilides, which induced >87% male sterility. Quantitative structure-activity relationship (QSAR) models indicated the positive contributions of the field effect exemplified by the Swain-Lupton constant (Fp) and negative contributions of the Swain-Lupton resonance constant (R) for the aromatic substitution. The positive influences of parachor (P) for the acyl domain have been underlined. These leads will be significant in explaining the CHA fit in the macromolecular receptor site. The CHAs appeared to act by causing an imbalance in the acid-base equilibrium in pollen mother cells resulting in dissolution of the callose wall by premature callase secretion. PMID:16939342

  14. Structural Studies on Acetylcholinesterase and Paraoxonase Directed Towards Development of Therapeutic Biomolecules for the Treatment of Degenerative Diseases and Protection Against Chemical Threat Agents

    NASA Astrophysics Data System (ADS)

    Sussman, Joel L.; Silman, Israel

    Acetylcholinesterase and paraoxonase are important targets for treatment of degenerative diseases, Alzheimer's disease and atherosclerosis, respectively, both of which impose major burdens on the health care systems in Western society. Acetylcholinesterase is the target of lethal nerve agents, and paraoxonase is under consideration as a bioscavenger for their detoxification. Both are thus the subject of research and development in the context of nerve agent toxicology. The crystal structures of the two enzymes are described, and structure/function relationships are discussed in the context of drug development and of development of means of protection against chemical threats.

  15. Demonstration of spread-on peel-off consumer products for sampling surfaces contaminated with pesticides and chemical warfare agent signatures.

    PubMed

    Behringer, Deborah L; Smith, Deborah L; Katona, Vanessa R; Lewis, Alan T; Hernon-Kenny, Laura A; Crenshaw, Michael D

    2014-08-01

    A terrorist attack using toxic chemicals is an international concern. The utility of rubber cement and latex body paint as spray-on/spread-on peel-off collection media for signatures attributable to pesticides and chemical warfare agents from interior building and public transportation surfaces two weeks post-deposition is demonstrated. The efficacy of these media to sample escalator handrail, stainless steel, vinyl upholstery fabric, and wood flooring is demonstrated for two pesticides and eight chemicals related to chemical warfare agents. The chemicals tested are nicotine, parathion, atropine, diisopropyl methylphosphonate, dimethyl methylphosphonate, dipinacolyl methylphosphonate, ethyl methylphosphonic acid, isopropyl methylphosphonic acid, methylphosphonic acid, and thiodiglycol. Amounts of each chemical found are generally greatest when latex body paint is used. Analytes with low volatility and containing an alkaline nitrogen or a sulfur atom (e.g., nicotine and parathion) usually are recovered to a greater extent than the neutral phosphonate diesters and acidic phosphonic acids (e.g., dimethyl methylphosphonate and ethyl methylphosphonic acid). PMID:24835029

  16. Absorbent Pads for Containment, neutralization, and clean-up of environmental spills containing chemically-reactive agents

    NASA Technical Reports Server (NTRS)

    Davis, Dennis D. (Inventor)

    1996-01-01

    A pad for cleaning up liquid spills is described which contains a porous surface covering, and an absorbent interior containing chemically reactive reagents for neutralizing noxious chemicals within the spilled liquid. The porous surface and the absorbent component would normally consist of chemically resistant materials allowing tentative spill to pass. The absorbent interior which contains the neutralizing reagents can but is not required to be chemically resilient and conducts the liquid chemically reactive reagents where the dangerous and undesirable chemicals within the chemical spill are then neutralized as well as removed from the premises.

  17. Occurrence and possible sources of arsenic in seafloor sediments surrounding sea-disposed munitions and chemical agents near O´ahu, Hawai´i

    NASA Astrophysics Data System (ADS)

    Tomlinson, Michael S.; De Carlo, Eric Heinen

    2016-06-01

    The Department of Defense disposed of conventional and chemical munitions as well as bulk containers of chemical agents in US coastal waters including those surrounding the State of Hawai´i. The Hawai´i Undersea Military Munitions Assessment has been collecting biota, water, and sediment samples from two disposal areas south of the island of O´ahu in waters 500 to 600 m deep known to have received both conventional munitions and chemical agents (specifically sulfur mustard). Unlike a number of other sea-disposed munitions investigations which used grabs or corers lowered from surface vessels, we used manned submersibles to collect the samples. Using this approach, we were able to visually identify the munitions and precisely locate our samples in relation to the munitions on the seafloor. This paper focuses on the occurrence and possible sources of arsenic found in the sediments surrounding the disposed military munitions and chemical agents. Using nonparametric multivariate statistical techniques, we looked for patterns in the chemical data obtained from these sediment samples in order to determine the possible sources of the arsenic found in these sediments. The results of the ordination technique nonmetric multidimensional scaling indicate that the arsenic is associated with terrestrial sources and not munitions. This was not altogether surprising given that: (1) the chemical agents disposed of in this area supposedly did not contain arsenic, and (2) the disposal areas studied were under terrestrial influence or served as dredge spoil disposal sites. The sediment arsenic concentrations during this investigation ranged from <1.3 to 40 mg/kg-dry weight with the lower concentrations typically found around control sites and munitions (not located in dredge disposal areas) and the higher values found at dredge disposal sites (with or without munitions). During the course of our investigation we did, however, discover that mercury appears to be loosely associated

  18. Effect of ionic interaction between a hyperpolarized magnetic resonance chemical probe and a gadolinium contrast agent for the hyperpolarized lifetime after dissolution

    NASA Astrophysics Data System (ADS)

    Takakusagi, Yoichi; Inoue, Kaori; Naganuma, Tatsuya; Hyodo, Fuminori; Ichikawa, Kazuhiro

    2016-09-01

    In hyperpolarization of 13C-enriched magnetic resonance chemical probes in the solid-state, a trace amount of gadolinium (Gd) contrast agent can be used to maximize polarization of the 13C nuclear spins. Here, we report systematic measurement of the spin-lattice relaxation time (T1) and enhancement level of 13C-enriched chemical probes in the presence of various Gd contrast agents in the liquid-state after dissolution. Using two different 13C probes having opposite electric charges at neutral pH, we clearly show the T1 of hyperpolarized 13C was barely affected by the use of a Gd complex that displays repulsive interaction with the 13C probe in solution, whilst T1 was drastically shortened when there was ionic attraction between probe and complex.

  19. Effect of ionic interaction between a hyperpolarized magnetic resonance chemical probe and a gadolinium contrast agent for the hyperpolarized lifetime after dissolution.

    PubMed

    Takakusagi, Yoichi; Inoue, Kaori; Naganuma, Tatsuya; Hyodo, Fuminori; Ichikawa, Kazuhiro

    2016-09-01

    In hyperpolarization of (13)C-enriched magnetic resonance chemical probes in the solid-state, a trace amount of gadolinium (Gd) contrast agent can be used to maximize polarization of the (13)C nuclear spins. Here, we report systematic measurement of the spin-lattice relaxation time (T1) and enhancement level of (13)C-enriched chemical probes in the presence of various Gd contrast agents in the liquid-state after dissolution. Using two different (13)C probes having opposite electric charges at neutral pH, we clearly show the T1 of hyperpolarized (13)C was barely affected by the use of a Gd complex that displays repulsive interaction with the (13)C probe in solution, whilst T1 was drastically shortened when there was ionic attraction between probe and complex. PMID:27490303

  20. Test operations procedure (TOP) 8-2-501, permeation and penetration of air-permeable, semipermeable, and impermeable materials with chemical agents or simulants (swatch testing). Final report

    SciTech Connect

    1997-03-03

    This test operations procedure (TOP) provides the current standard for planning and conducting tests to measure the permeation or penetration of swatches of materials by chemical agents such as distilled mustard (HD), or the nerve agents sarin (GB), or V-agent (VX). The swatches may be single or multi-layered, inert, sorptive or reactive. Swatches may be taken from candidate or standardized fabrics, in which case application of this TOP can provide relative ranking or screening information about the ability of the standardized and/or candidate materials to resist permeation or penetration by chemical agents. Swatches may also be taken from garments that are new, have been stored, or have been worn for various times under different conditions. Testing these material swatches using the procedures in the TOP can provide data to evaluate the effects of the different condition of wear. This TOP is not adequate for the assessment of the ability of an end item clothing made from any tested material to protect the wearer. The data obtained by these procedures cannot be correlated to field conditions. One or more of the test procedures given may be required in a detailed test plan (DTP).