Multivariate soil fertility relationships for predicting the environmental persistence of 2,4,6-trinitrotoluene (TNT) and 1,3,5-trinitro-1,3,5-tricyclohexane (RDX) among taxonomically distinct soils.

Science.gov (United States)

Katseanes, Chelsea K; Chappell, Mark A; Hopkins, Bryan G; Durham, Brian D; Price, Cynthia L; Porter, Beth E; Miller, Lesley F

2017-12-01

After nearly a century of use in numerous munition platforms, TNT and RDX contamination has turned up largely in the environment due to ammunition manufacturing or as part of releases from low-order detonations during training activities. Although the basic knowledge governing the environmental fate of TNT and RDX are known, accurate predictions of TNT and RDX persistence in soil remain elusive, particularly given the universal heterogeneity of pedomorphic soil types. In this work, we proposed overcoming this problem by considering the environmental persistence of these munition constituents (MC) as multivariate mathematical functions over a variety of taxonomically distinct soil types, instead of a single constant or parameter of a specific absolute value. To test this idea, we conducted experiments where the disappearance kinetics of TNT and RDX were measured over a >300 h period in taxonomically distinct soils. Classical fertility-based soil measurements were log-transformed, statistically decomposed, and correlated to TNT and RDX disappearance rates (k -TNT and k -RDX ) using multivariate dimension-reduction and correlation techniques. From these efforts, we generated multivariate linear functions for k parameters across different soil types based on a statistically reduced set of their chemical and physical properties: Calculations showed that the soil properties exhibited strong covariance, with a prominent latent structure emerging as the basis for relative comparisons of the samples in reduced space. Loadings describing TNT degradation were largely driven by properties associated with alkaline/calcareous soil characteristics, while the degradation of RDX was attributed to the soil organic matter content - reflective of an important soil fertility characteristic. In spite of the differing responses to the munitions, batch data suggested that the overall nutrient dynamics were consistent for each soil type, as well as readily distinguishable from the other

The Effect of Light Casings on the Blast Parameters from a Spherical Charge of RDX/TNT 60/40

National Research Council Canada - National Science Library

Bishop, Valerie J; James, D. J

1968-01-01

.... High speed cine films were taken of the fireball growth. Peak overpressure and impulse enhancement over the values from an uncased RDX/TNT charge were obtained only from the thickest lead casing...

Investigating a Drop-on-Demand Microdispenser for Standardized Sample Preparation

Science.gov (United States)

2012-09-01

potassium chlorate were obtained from Sigma-Aldrich. 1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7- tetranitro-tetrazocine (HMX), 2,4,6... potassium chlorate , HMX, TNT, RDX, PETN, urea, and sugar. The analyte of interest was dissolved in the appropriate solvent and then diluted to various

HMX based enhanced energy LOVA gun propellant

Energy Technology Data Exchange (ETDEWEB)

Sanghavi, R.R. [High Energy Materials Research Laboratory, Pune 411021 (India)]. E-mail: sanghavirr@yahoo.co.uk; Kamale, P.J. [High Energy Materials Research Laboratory, Pune 411021 (India); Shaikh, M.A.R. [High Energy Materials Research Laboratory, Pune 411021 (India); Shelar, S.D. [High Energy Materials Research Laboratory, Pune 411021 (India); Kumar, K. Sunil [High Energy Materials Research Laboratory, Pune 411021 (India); Singh, Amarjit [High Energy Materials Research Laboratory, Pune 411021 (India)

2007-05-08

Efforts to develop gun propellants with low vulnerability have recently been focused on enhancing the energy with a further improvement in its sensitivity characteristics. These propellants not only prevent catastrophic disasters due to unplanned initiation of currently used gun propellants (based on nitrate esters) but also realize enhanced energy levels to increase the muzzle velocity of the projectiles. Now, in order to replace nitroglycerine, which is highly sensitive to friction and impact, nitramines meet the requirements as they offer superior energy due to positive heat of formation, typical stoichiometry with higher decomposition temperatures and also owing to negative oxygen balance are less sensitive than stoichiometrically balanced NG. RDX has been widely reported for use in LOVA propellant. In this paper we have made an effort to present the work on scantily reported nitramine HMX based LOVA gun propellant while incorporating energetic plasticizer glycidyl azide polymer to enhance the energy level. HMX is known to be thermally stable at higher temperature than RDX and also proved to be less vulnerable to small scale shaped charge jet attack as its decomposition temperature is 270 deg. C. HMX also offers improved impulse due to its superior heat of formation (+17 kcal/mol) as compared to RDX (+14 kcal/mol). It has also been reported that a break point will not appear until 35,000 psi for propellant comprising of 5 {mu}m HMX. Since no work has been reported in open literature regarding replacement of RDX by HMX, the present studies were carried out.

Relationship between RDX properties and sensitivity

Energy Technology Data Exchange (ETDEWEB)

Doherty, Ruth M. [Research, Development, Test and Evaluation Directorate, Naval Surface Warfare Center Indian Head Division, Indian Head, MD 20640-5102 (United States); Watt, Duncan S. [Novare, Level 6 80 Petrie Terrace, Brisbane 4000 (Australia)

2008-02-15

An interlaboratory comparison of seven lots of commercially available RDX was conducted to determine what properties of the nitramine particles can be used to assess whether the RDX has relatively high or relatively low sensitivity. The materials chosen for the study were selected to give a range of HMX content, manufacturing process and reported shock sensitivity. The results of two different shock sensitivity tests conducted on a PBX made with the RDX lots in the study showed that there are measurable differences in the shock sensitivity of the PBXs, but the impact sensitivity for all of the lots is essentially the same. Impact sensitivity is not a good predictor of shock sensitivity for these types of RDX. Although most RDX that exhibits RS has low HMX content, that characteristic alone is not sufficient to guarantee low sensitivity. A range of additional analytical chemistry tests were conducted on the material; two of these (HPLC and DSC) are discussed within. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

Mechanical and chemical responses of low-velocity impacted RDX and HMX explosive powders

Science.gov (United States)

Wu, Yanqing; Guo, Hongfu; Huang, Fenglei; Bao, Xiaowei; Explosion; damage Team

2017-06-01

The experimental analyses of mechanical and chemical responses of RDX and HMX particles were performed based on the optimized drop-weight experimental system equipped with the High-Speed Camera (HSC). It has been found that Jetting phenomenon observed by HSC is the result of the energy released by gaseous products, which push the pulverized or melted explosives to splash radially. Jetting is the only and the most obvious difference between reactive and inert particles prior to combustion so that jetting can be regarded as the sign of ignition. Area expansion velocity, jetting velocity, and flame propagation velocity have been estimated via image processing, making it possible to characterize mechanical deformation and violence of reaction of each stage. Hot-spots coalescence promotes flame propagation whose velocity reflects the violence of deflagration reaction. Jetting appearance time can be used to determine time-to-ignition more accurately than other ways. For RDX, molten phase plays an important role to the formation of the hot-spots. Multiple particles experienced more severe burning reactions than an individual particle. China National Nature Science Foundation (11572045), ``Science Challenging Program'' (JCKY2016212A501),opening fund from Safety ammunition research and Development Center (RMC2015B03).

Environmental Behavior and Fate of Explosives in Groundwater from the Milan Army Ammunition Plant in Aquatic and Wetland Plants. Fate of TNT and RDX

National Research Council Canada - National Science Library

Best, Elly

1998-01-01

The present study was performed to elucidate the environmental behavior and fate of TNT and RDX in aquatic and wetland plants collected from a field-scale wetland demonstration deployed at Milan Army...

Biodegradation of Nitro-Substituted Explosives 2,4,6-Trinitrotoluene, Hexahydro-1,3,5-Trinitro-1,3,5-Triazine, and Octahydro-1,3,5,7-Tetranitro-1,3,5-Tetrazocine by a Phytosymbiotic Methylobacterium sp. Associated with Poplar Tissues (Populus deltoides × nigra DN34)

Science.gov (United States)

Van Aken, Benoit; Yoon, Jong Moon; Schnoor, Jerald L.

2004-01-01

A pink-pigmented symbiotic bacterium was isolated from hybrid poplar tissues (Populus deltoides × nigra DN34). The bacterium was identified by 16S and 16S-23S intergenic spacer ribosomal DNA analysis as a Methylobacterium sp. (strain BJ001). The isolated bacterium was able to use methanol as the sole source of carbon and energy, which is a specific attribute of the genus Methylobacterium. The bacterium in pure culture was shown to degrade the toxic explosives 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazene (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5-tetrazocine (HMX). [U-ring-14C]TNT (25 mg liter−1) was fully transformed in less than 10 days. Metabolites included the reduction derivatives amino-dinitrotoluenes and diamino-nitrotoluenes. No significant release of 14CO2 was recorded from [14C]TNT. In addition, the isolated methylotroph was shown to transform [U-14C]RDX (20 mg liter−1) and [U-14C]HMX (2.5 mg liter−1) in less than 40 days. After 55 days of incubation, 58.0% of initial [14C]RDX and 61.4% of initial [14C]HMX were mineralized into 14CO2. The radioactivity remaining in solution accounted for 12.8 and 12.7% of initial [14C]RDX and [14C]HMX, respectively. Metabolites detected from RDX transformation included a mononitroso RDX derivative and a polar compound tentatively identified as methylenedinitramine. Since members of the genus Methylobacterium are distributed in a wide diversity of natural environments and are very often associated with plants, Methylobacterium sp. strain BJ001 may be involved in natural attenuation or in situ biodegradation (including phytoremediation) of explosive-contaminated sites. PMID:14711682

Characterization of the Morphology of RDX Particles Formed by Laser Ablation

Science.gov (United States)

2012-02-01

military-grade RDX can contain significant amounts of HMX (up to 5% for type-I RDX produced by direct nitration with the Woolwich process and up to...potentially produce RDX particles with specific morphologies in support of microstructural experiments for the Multiscale Response of Energetic

Halide salts accelerate degradation of high explosives by zerovalent iron

International Nuclear Information System (INIS)

Kim, Jong Sung; Shea, Patrick J.; Yang, Jae E.; Kim, Jang-Eok

2007-01-01

Zerovalent iron (Fe 0 , ZVI) has drawn great interest as an inexpensive and effective material to promote the degradation of environmental contaminants. A focus of ZVI research is to increase degradation kinetics and overcome passivation for long-term remediation. Halide ions promote corrosion, which can increase and sustain ZVI reactivity. Adding chloride or bromide salts with Fe 0 (1% w/v) greatly enhanced TNT, RDX, and HMX degradation rates in aqueous solution. Adding Cl or Br salts after 24 h also restored ZVI reactivity, resulting in complete degradation within 8 h. These observations may be attributed to removal of the passivating oxide layer and pitting corrosion of the iron. While the relative increase in degradation rate by Cl - and Br - was similar, TNT degraded faster than RDX and HMX. HMX was most difficult to remove using ZVI alone but ZVI remained effective after five HMX reseeding cycles when Br - was present in solution. - The addition of halide ions promotes the degradation of high explosives by zerovalent iron

Treatment of groundwater contaminated with low levels of military munitions

International Nuclear Information System (INIS)

Bricka, R.M.; Sharp, W.

1993-01-01

The site of interest is a military base that was established in the late 1800s. In its early history this facility was used as a powder depot to fill projectiles with miximite (a propellant). Since World War I, this facility was used to produce artillery ammunition, bombs, high explosives, pyrotechnics and other ordinances. Weapons production at this facility has ceased, but as a result of the past activities at this facility, contaminants are migrating into the groundwater. One source of drinking water for this installation is a screened well in a stratified-drift aquifer system at a depth of 75-85 feet below land surface. In the 1980s sampling of this well revealed low level contamination of trichloroethylene (TCE), RDX and HMX. TCE levels exceeded drinking water standards and an air stripping column was installed to remove the TCE. RDX and HMX, concentrations were below drinking water standards. Health Advisory (HA) levels for RDX and HMX were published by the U.S. Environmental Protection Agency (USEPA) in November 1988. The lifetime HA levels are 2 ppb and 400 ppb for RDX and HMX, respectively (McLellan et al. 1988a, and McLellan et al. 1988b). It is expected that continuous withdrawals from this well will increase RDX and HMX concentrations. In addition, it is believed that future USEPA regulations will adapt the HA as a drinking water standard. This study was initiated in an effort to have an appropriate cost effective technology ready to meet any such standard. RDX and HMX RDX and HMX are military explosives. RDX (Hexahydro-l,3,5-trinitro-l,3,5-triazine) is a code name for Research Department Explosive. This explosive is described as a white crystalline solid with about 1.3 times the explosive power of trinitrotoluene (TNT). RDX is classified as a EPA Group C compound: Possible Human Carcinogen (McLellan et. al. 1988a). HMX (Octahydro-1, 3, 5, 7- tetranitro-l, 3, 5, 7-tetrazocine) is a code name for High Melting Explosive. This explosive is described as a

USE OF SERIAL ANALYSIS OF GENE EXPRESSION (SAGE) TO STUDY GENETIC RESPONSES TO THE PRESENCE OF THE TNT OR RDX BY ARABIDOPSIS THALIANA

Science.gov (United States)

Phytoremediation is currently being explored for its potential to clean-up of the large number of military sites that have been contaminated by explosives such as 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). Although some of the enzymes responsi...

Synthesis of 14C-Labelled Octahydor-1,3,5,7-Tetranitro-1,3,5,7-Tetrazocine (HMx0 and 15N-Isotopic Hexahyrro-1,3,5-Trinitro-1,3,5-Triazine (RDX) for use in Microcosm Experiments

National Research Council Canada - National Science Library

Ampleman, G

2000-01-01

Within the framework of an R & D project on bioremediation of soils contaminated with energetic compounds, the biodegradation of energetic nitramine products such as octogen (HMX) and hexogen (RDX) is under study...

Modeling Nonlinear Elastic-plastic Behavior of RDX Single Crystals During Indentation

Science.gov (United States)

2012-01-01

single crystals has also been probed using shock experiments (6, 12) and molecular dynamics simulations (12–14). RDX undergoes a polymorphic phase...Patterson, J.; Dreger, Z.; Gupta, Y. Shock-wave Induced Phase Transition in RDX Single Crystals. J. Phys. Chem. B 2007, 111, 10897–10904. 17. Bedrov, D...and Volume Compression of β - HMX and RDX . In Proc. Int. Symp. High Dynamic Pressures; Commissariat a l’Energie Atomique: Paris, 1978; pp 3–8. 24

Spectrophotometric determination of cyclotrimethylenetrinitramine (RDX) in explosive mixtures and residues with the Berthelot reaction.

Science.gov (United States)

Uzer, A; Erçağ, E; Apak, R

2008-03-31

On-site colorimetric methods are a valuable, cost-effective tool to assess the nature and extent of contamination in remediated sites and to enable on-site screening for police criminology laboratories. The existing colorimetric method for cyclotrimethylenetrinitramine (RDX) based on a Griess reaction suffers from the non-quantitative reduction to nitrite and from the unstable character of HNO2 in acidic medium. Thus we propose a novel spectrophotometric RDX assay in explosive mixtures and residues, based on (Zn+HCl) reduction of RDX in a microwave oven, followed by neutralization of the reduction products to ammonia and low molecular-weight amines, and Berthelot reaction of these amine-compounds with phenol and hypochlorite in alkaline medium to give an intensely blue indophenol dye absorbing at 631nm. The molar absorptivity and limit of detection (LOD) for RDX were (1.08+/-0.04)x10(4) L mol(-1) cm(-1) and 0.18 mg L(-1), respectively. Application of the method to synthetic mixture solutions of RDX and trinitrotoluene (TNT) at varying proportions showed that there was minimal interference from TNT (which could be compensated for by dicyclohexylamine colorimetry), since the Berthelot reaction was essentially non-responsive to m-substituted anilines derived from TNT upon (Zn+HCl) reduction. The proposed method was successfully applied to military-purpose explosive mixtures of (RDX+inert matter) such as Comp A5, Comp C4, and Hexal P30, and to (RDX+TNT) mixtures such as Comp B. The molar absorptivity of RDX was much higher than that of either ammonium or nitrate; RDX could be effectively separated from ammonium and nitrate in soil mixtures, based on solubility differences. The Berthelot method for RDX was statistically validated using Comp B mixtures against standard HPLC equipped with a Hypersil C-18 column with (40% MeOH-60% H2O) mobile phase, and against gas chromatography-thermal energy analysis (GC-TEA) system.

Remediation Using Plants and Plant Enzymes: A Progress Report

National Research Council Canada - National Science Library

1995-01-01

.... In every case, the sources are plants growing near the sediment. The use of plants for remediation of hazardous materials such as TNT or other munitions like RDX and HMX has led to a new approach to remediation-- phytoremediation...

Specific Heat of Octahydro - 1,3,5,7 - Tetranitro - 1,3,5,7 - Tetrazocine (HMX).

Science.gov (United States)

1983-01-01

impurities probably consist of molecules of similar atomic weights as those present in the HMX molecule. Usually the major impurity in HMX is RDX (5...crystal and powdered blend HMX . Data beyond the normal transformation temperature (i.e. 0*6 transition ) were obtained from 472 to 486*K. Also, due to the...Cady, H.H.; Smith, L.C., "Studies on the Polymorphs of HMX ," Los Alamos Scientific Laboratory, Los Alamos, N.M., LAMS-2652, May 1962. (6) Brill, T.B

Mass Spectrometric Analysis of Eight Common Chemical Explosives Using Ion Trap Mass Spectrometer

Energy Technology Data Exchange (ETDEWEB)

Park, Sehwan; Lee, Jihyeon; KIm, Jeongkwon [Chungnam National Univ., Daejeon (Korea, Republic of); Cho, Soo Gyeong; Goh, Eun Mee [Agency for Defense Development, Daejeon (Korea, Republic of); Lee, Sungman; Koh, Sungsuk [Sensor Tech Inc., Seoul (Korea, Republic of)

2013-12-15

Eight representative explosives (ammonium perchlorate (AP), ammonium nitrate (AN), trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), cyclonite (RDX), cyclotetramethylenetetranitramine (HMX), pentaerythritol tetranitrate (PETN), and hexanitrostilbene (HNS)) were comprehensively analyzed with an ion trap mass spectrometer in negative ion mode using direct infusion electrospray ionization. MS/MS experiments were performed to generate fragment ions from the major parent ion of each explosive. Explosives in salt forms such as AP or AN provided cluster parent ions with their own anions. Explosives with an aromatic ring were observed as either [M.H]{sup -} for TNT and DNT or [M]{sup ·-}. for HNS, while explosives without an aromatic ring such as RDX, HMX, and PETN were detected as an adduct ion with a formate anion, i. e., [M+HCOO]{sup -}. These findings provide a guideline for the rapid and accurate detection of explosives once portable MS instruments become more readily available.

Mass Spectrometric Analysis of Eight Common Chemical Explosives Using Ion Trap Mass Spectrometer

International Nuclear Information System (INIS)

Park, Sehwan; Lee, Jihyeon; KIm, Jeongkwon; Cho, Soo Gyeong; Goh, Eun Mee; Lee, Sungman; Koh, Sungsuk

2013-01-01

Eight representative explosives (ammonium perchlorate (AP), ammonium nitrate (AN), trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), cyclonite (RDX), cyclotetramethylenetetranitramine (HMX), pentaerythritol tetranitrate (PETN), and hexanitrostilbene (HNS)) were comprehensively analyzed with an ion trap mass spectrometer in negative ion mode using direct infusion electrospray ionization. MS/MS experiments were performed to generate fragment ions from the major parent ion of each explosive. Explosives in salt forms such as AP or AN provided cluster parent ions with their own anions. Explosives with an aromatic ring were observed as either [M.H] - for TNT and DNT or [M] ·- . for HNS, while explosives without an aromatic ring such as RDX, HMX, and PETN were detected as an adduct ion with a formate anion, i. e., [M+HCOO] - . These findings provide a guideline for the rapid and accurate detection of explosives once portable MS instruments become more readily available

Treatment of RDX & HMX Plumes Using Mulch Biowalls

Science.gov (United States)

2008-08-01

BAK Benzalkonium chloride BGS Below Ground Surface BRAC Base Realignment and Closure CHAAP Cornhusker Army Ammunition Plant CDPHE Colorado...Metabolism, and Reductive Transformation of RDX .............................................................. 9  Figure 4. Plan View Schematic of...43  Figure 17. Oxidation- reduction Potential (ORP) Measurement Averaged Over Different Well- rows

Computational Study of the Structure and Mechanical Properties of the Molecular Crystal RDX

Science.gov (United States)

2012-11-01

basic equilibrium properties of and transitions to and from the α and γ polymorphs in crystalline RDX based on the SB potential (17). Atomic-level...elastic constants, polymorph transitions , cleavage properties, and energy barriers to slip. The energy barriers to slip are determined through the... RDX molecule containing three R2N-NO2 groups, where each R=CH2; and (c) HMX molecule containing four R2N-NO2 groups with R=CH2

Ultra-violet and visible absorption characterization of explosives by differential reflectometry.

Science.gov (United States)

Dubroca, Thierry; Moyant, Kyle; Hummel, Rolf E

2013-03-15

This study presents some optical properties of TNT (2,4,6-trinitrotoluene), RDX, HMX and tetryl, specifically their absorption spectra as a function of concentration in various solvents in the ultraviolet and visible portion of the electromagnetic spectrum. We utilize a standoff explosives detection method, called differential reflectometry (DR). TNT was diluted in six different solvents (acetone, acetonitrile, ethanol, ethyl acetate, methanol, and toluene), which allowed for a direct comparison of absorption features over a wide range of concentrations. A line-shape analysis was adopted with great accuracy (R(2)>0.99) to model the absorption features of TNT in differential reflectivity spectra. We observed a blue shift in the pertinent absorption band with decreasing TNT concentration for all solvents. Moreover, using this technique, it was found that for all utilized solvents the concentration of TNT as well as of RDX, HMX, and tetryl, measured as a function of the transition wavelength of the ultra-violet absorption edge in differential reflectivity spectra shows three distinct regions. A model is presented to explain this behavior which is based on intermolecular hydrogen bonding of explosives molecules with themselves (or lack thereof) at different concentrations. Other intermolecular forces such as dipole-dipole interactions, London dispersion forces and π-stacking contribute to slight variations in the resulting spectra, which were determined to be rather insignificant in comparison to hydrogen bonding. The results are aimed towards a better understanding of the DR spectra of explosives energetic materials. Copyright © 2012 Elsevier B.V. All rights reserved.

Computations on Internal Blast from Titanium-Cased Charges in Air

Science.gov (United States)

1984-07-01

formation and considerable temperature- dependent polymorphic transition . Oxygen is soluble in titanium metal to the extent of about 25 atom-percent, yielding...15 CSH8N4O1 2 NC Nitrocellulose, 13.3% N; -812.9 +3 C6H7N2.5010 HMX symn-Cyclotetramnethylene- + 77.4 0 tetranitramine, C4HSNBO8 Pentolite 50% PETN, 50...TNT; -97.9 -5 C6.1 6H6 .2 5N3.41085. Comp 8 65% RDX , 35% TNT; + 11.47 -9 C1 .96H2. 53N2.2202.68 TNT 2,4,6-Trinitrotoluene, +30.7 -25 p C7R 5N306 N2

Development of a remediation strategy for surface soils contaminated with energetic materials by thermal processes: Phases 1, 2 and 3

Science.gov (United States)

2009-11-01

aerobic and thermophilic (55 to 60°C) conditions, which foster the growth of microorganisms. Bulking agents, such as cow manure and vegetable waste and...streams. In bench-scale testing, the EPA National Exposure Research Laboratory in Athens, GA, has identified a plant nitroreductase enzyme shown to...degrade TNT, RDX and HMX in concert with other plant enzymes . An immunoassay test has been developed that identifies nitroreductase activity in a

Standardized Sample Preparation Using a Drop-on-Demand Printing Platform

Science.gov (United States)

2013-05-07

and Materials Ammonium nitrate (AN), methanol (MeOH), distilled water (H2O), acetonitrile, sugar, urea, and potassium chlorate (KClO3) were...various pre-determined energetic and interferent compounds. The evaluated analytes were: AN, potassium chlorate , HMX, TNT, RDX, PETN, urea, and...KClO3 molecules dissolving and then breaking into potassium and chlorate ions in H2O. An additional concern was the interaction of adjacent

Quasi-dynamic pressure and temperature initiated βδ solid phase transitions in HMX

Science.gov (United States)

Zaug, Joseph M.; Farber, Daniel L.; Craig, Ian M.; Blosch, Laura L.; Shuh, David K.; Hansen, Donald W.; Aracne-Ruddle, Chantel M.

2000-04-01

The phase transformation of β-HMX (>0.5% RDX) to δ phase has been studied for over twenty years and more recently with an high-contrast optical second harmonic generation technique. Shock studies of the plastic binder composites of HMX have indicated that the transition is perhaps irreversible, a result that concurs with the static pressure results published by F. Goetz et al. [1] in 1978. However, the stability field favors the β polymorph over δ as pressure is increased (up to 5.4 GPa) along any thermodynamically reasonable isotherm. In this experiment, strict control of pressure and temperature is maintained while x-ray and optical diagnostics are applied to monitor the conformational dynamics of HMX. Unlike the temperature induced β→δ transition, the pressure induced is heterogeneous in nature. The 1 bar 25 °C δ→β transition is not immediate, occuring over tens of hours. Transition points and kinetics are path dependent and consequently this paper describes our work in progress.

Bioremediation of RDX in the vadose zone beneath the Pantex Plant

Energy Technology Data Exchange (ETDEWEB)

Shull, T.L.; Speitel, G.E. Jr.; McKinney, D.C. [Univ. of Texas, Austin, TX (United States). Dept. of Civil Engineering

1999-01-01

The presence of dissolved high explosives (HE), in particular RDX and HMX, is well documented in the perched aquifer beneath the Pantex Plant, but the distribution of HE in the vadose zone has not yet been well defined. Although current remediation activities focus on the contamination in the perched aquifer, eventually regulatory concern is likely to turn to the residual contamination in the vadose zone. Sources of HE include the infiltration of past wastewater discharges from several HE-processing facilities through the ditch drainage system and leachate from former Landfill 3. With limited existing data on the HE distribution in the vadose zone and without preventive action, it must be assumed that residual HE could be leached into infiltrating water, providing a continuing supply of contamination to the perched aquifer. The purpose of this project was to more closely examine the fate and transport of HE in the vadose zone through mathematical modeling and laboratory experimentation. In particular, this report focuses on biodegradation as one possible fate of HE. Biodegradation of RDX in the vadose zone was studied because it is both present in highest concentration and is likely to be of the greatest regulatory concern. This study had several objectives: determine if indigenous soil organisms are capable of RDX biodegradation; determine the impact of electron acceptor availability and nutrient addition on RDX biodegradation; determine the extent of RDX mineralization (i.e., conversion to inorganic carbon) during biodegradation; and estimate the kinetics of RDX biodegradation to provide information for mathematical modeling of fate and transport.

Shock-to-detonation transition of RDX and NTO based composite high explosives: experiments and modeling

Science.gov (United States)

Baudin, Gerard; Roudot, Marie; Genetier, Marc

2013-06-01

Composite HMX and NTO based high explosives (HE) are widely used in ammunitions. Designing modern warheads needs robust and reliable models to compute shock ignition and detonation propagation inside HE. Comparing to a pressed HE, a composite HE is not porous and the hot-spots are mainly located at the grain - binder interface leading to a different behavior during shock-to-detonation transition. An investigation of how shock-to-detonation transition occurs inside composite HE containing RDX and NTO is proposed in this lecture. Two composite HE have been studied. The first one is HMX - HTPB 82:18. The second one is HMX - NTO - HTPB 12:72:16. These HE have been submitted to plane sustained shock waves at different pressure levels using a laboratory powder gun. Pressure signals are measured using manganin gauges inserted at several distances inside HE. The corresponding run-distances to detonation are determined using wedge test experiments where the plate impact is performed using a powder gun. Both HE exhibit a single detonation buildup curve in the distance - time diagram of shock-to-detonation transition. This feature seems a common shock-to-detonation behavior for composite HE without porosity. This behavior is also confirmed for a RDX - HTPB 85:15 based composite HE. Such a behavior is exploited to determine the heterogeneous reaction rate versus the shock pressure using a method based on the Cauchy-Riemann problem inversion. The reaction rate laws obtained allow to compute both run-distance to detonation and pressure signals.

Thermal Decomposition Behaviors and Burning Characteristics of AN/Nitramine-Based Composite Propellant

Science.gov (United States)

Naya, Tomoki; Kohga, Makoto

2015-04-01

Ammonium nitrate (AN) has attracted much attention due to its clean burning nature as an oxidizer. However, an AN-based composite propellant has the disadvantages of low burning rate and poor ignitability. In this study, we added nitramine of cyclotrimethylene trinitramine (RDX) or cyclotetramethylene tetranitramine (HMX) as a high-energy material to AN propellants to overcome these disadvantages. The thermal decomposition and burning rate characteristics of the prepared propellants were examined as the ratio of AN and nitramine was varied. In the thermal decomposition process, AN/RDX propellants showed unique mass loss peaks in the lower temperature range that were not observed for AN or RDX propellants alone. AN and RDX decomposed continuously as an almost single oxidizer in the AN/RDX propellant. In contrast, AN/HMX propellants exhibited thermal decomposition characteristics similar to those of AN and HMX, which decomposed almost separately in the thermal decomposition of the AN/HMX propellant. The ignitability was improved and the burning rate increased by the addition of nitramine for both AN/RDX and AN/HMX propellants. The increased burning rates of AN/RDX propellants were greater than those of AN/HMX. The difference in the thermal decomposition and burning characteristics was caused by the interaction between AN and RDX.

Molecular Dynamics in Nitramines and Modified Nitramines

Science.gov (United States)

1983-11-01

34melts"? Uhat is the structure of RDX and HMX molecules in the "melt", solution, and ,gas phases? What is the structure of the O- RDX polymorph ? These... RDX molecule has 4sentially 3v oeulrsrutr L~j -in all environments except the stable solid"V- RDX ph&*e. The RDX and HMX --~J meslts were found to be...otion and phase transition characteristics of HMX . These studies involve approaches not previously used in this field such as 14 N nuclear quadrupole

Studies of the laser-induced fluorescence of explosives and explosive compositions.

Energy Technology Data Exchange (ETDEWEB)

Hargis, Philip Joseph, Jr. (,; .); Thorne, Lawrence R.; Phifer, Carol Celeste; Parmeter, John Ethan; Schmitt, Randal L.

2006-10-01

Continuing use of explosives by terrorists throughout the world has led to great interest in explosives detection technology, especially in technologies that have potential for standoff detection. This LDRD was undertaken in order to investigate the possible detection of explosive particulates at safe standoff distances in an attempt to identify vehicles that might contain large vehicle bombs (LVBs). The explosives investigated have included the common homogeneous or molecular explosives, 2,4,6-trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), cyclonite or hexogen (RDX), octogen (HMX), and the heterogeneous explosive, ammonium nitrate/fuel oil (ANFO), and its components. We have investigated standard excited/dispersed fluorescence, laser-excited prompt and delayed dispersed fluorescence using excitation wavelengths of 266 and 355 nm, the effects of polarization of the laser excitation light, and fluorescence imaging microscopy using 365- and 470-nm excitation. The four nitro-based, homogeneous explosives (TNT, PETN, RDX, and HMX) exhibit virtually no native fluorescence, but do exhibit quenching effects of varying magnitude when adsorbed on fluorescing surfaces. Ammonium nitrate and fuel oil mixtures fluoresce primarily due to the fuel oil, and, in some cases, due to the presence of hydrophobic coatings on ammonium nitrate prill or impurities in the ammonium nitrate itself. Pure ammonium nitrate shows no detectable fluorescence. These results are of scientific interest, but they provide little hope for the use of UV-excited fluorescence as a technique to perform safe standoff detection of adsorbed explosive particulates under real-world conditions with a useful degree of reliability.

Feature extraction using distribution representation for colorimetric sensor arrays used as explosives detectors

DEFF Research Database (Denmark)

Alstrøm, Tommy Sonne; Raich, Raviv; Kostesha, Natalie

2012-01-01

is required. We present a new approach of extracting features from a colorimetric sensor array based on a color distribution representation. For each sensor in the array, we construct a K-nearest neighbor classifier based on the Hellinger distances between color distribution of a test compound and the color......We present a colorimetric sensor array which is able to detect explosives such as DNT, TNT, HMX, RDX and TATP and identifying volatile organic compounds in the presence of water vapor in air. To analyze colorimetric sensors with statistical methods, a suitable representation of sensory readings...

(Bio)degradation of RDX and HMX in Marine/Estuarine Water and Sediments

Science.gov (United States)

2006-09-01

four fungal strains Rhodotorula sp . HAW-OCF1, Bullera sp . HAW-OCF2, Acremonium sp . HAW-OCF3 and Penicillium sp . HAW-OCF5, were isolated as RDX...represent four novel species of Shewanella described as follows: Shewanella sediminis sp . nov.: Strain HAW-EB3T contains lysine decarboxylase that is...We proposed Shewanella sediminis sp . nov. with HAW-EB3T (= NCIMB 14036T = DSM 17055T) as the type strain (Zhao et al. 2005). Shewanella halifaxensis

Shock initiation sensitivity and Hugoniot-based equation of state of Composition B obtained using in situ electromagnetic gauging

International Nuclear Information System (INIS)

Gibson, L L; Bartram, B D; Sheffield, S A; Gustavsen, R L; Brown, G W; Sandstrom, M M; Giambra, A M; Dattelbaum, D M; Handley, C A

2014-01-01

A series of gas gun-driven plate impact experiments were performed on vacuum melt-cast Composition B to obtain new Hugoniot states and shock sensitivity (run-distance-to-detonation) information. The Comp B (ρ 0 = 1.713 g/cm 3 ) consisted of 59.5% RDX, 39.5% TNT, and 1% wax, with ∼ 6.5% HMX in the RDX. The measured Hugoniot states were found to be consistent with earlier reports, with the compressibility on the shock adiabat softer than that of a 63% RDX material reported by Marsh.[4] The shock sensitivity was found to be more sensitive (shorter run distance to detonation at a given shock input condition) than earlier reports for Comp B-3 and a lower density (1.68-1.69 g/cm 3 ) Comp B formulation. The reactive flow during the shock-to-detonation transition was marked by heterogeneous, hot spot-driven growth both in and behind the leading shock front.

Adsorption of TNT, DNAN, NTO, FOX7, and NQ onto cellulose, chitin, and cellulose triacetate. Insights from Density Functional Theory calculations

Science.gov (United States)

Todde, Guido; Jha, Sanjiv K.; Subramanian, Gopinath; Shukla, Manoj K.

2018-02-01

Insensitive munitions (IM) compounds such as DNAN (2,4-dinitroanisole), NTO (3-nitro-1,2,4-triazol-5-one), NQ (nitroguanidine), and FOX7 (1,1-diamino-2,2-dinitroethene) reduce the risk of accidental explosions due to shock and high temperature exposure. These compounds are being used as replacements for sensitive munition compounds such as TNT (2,4,6-trinitromethylbenzene) and RDX (1,3,5-hexahydro-1,3,5-trinitro-1,3,5-triazine). NTO and NQ in IM compounds are more soluble than TNT or RDX, hence they can easily spread in the environment and get dissolved if exposed to precipitation. DNAN solubility is comparable to TNT solubility. Cellulosic biomass, due to its abundance in the environment and its chemical structure, has a high probability of adsorbing these IM compounds, and thus, it is important to investigate the interactions between cellulose and cellulose like biopolymers (e.g. cellulose triacetate and chitin) with IM compounds. Using Density Functional Theory methods, we have studied the adsorption of TNT, DNAN, NTO, NQ, and FOX7 onto cellulose Iα and Iβ, chitin, and cellulose triacetate I (CTA I). Solvent effects on the adsorption were also investigated. Our results show that all contaminants are more strongly adsorbed onto chitin and cellulose Iα than onto CTA I and cellulose Iβ. Dispersion forces were found to be the predominant contribution to the adsorption energies of all contaminants.

1983 AFOSR/AFRPL Chemical Rocket Research Meeting, Abstracts and Agenda. Includes: Abstracts on Advanced Diagnostics of Reacting Flow, 28 February - 3 March 1983, Lancaster, California.

Science.gov (United States)

1983-02-01

0w 5680 RDX as they do in HMX . 5600 - 98 198 298 398 Temp. (K) A SECOND POLYMORPH OF RDX • I’ s . II !Th,"’rieI Spectral evidence of the second...Bernecker, R. R., and D. Price, Combustion and Flame, 22:111 (1974). 3. Campbell, A. W., "Deflagration-to-Detonation Transition in Granular HMX ," 1980...thermophysical properties of HMX , RDX , and AP are being made. Shown in Figure I is the general approach for making the thermophysical property determinations

A laser-based FAIMS detector for detection of ultra-low concentrations of explosives

Science.gov (United States)

Akmalov, Artem E.; Chistyakov, Alexander A.; Kotkovskii, Gennadii E.; Sychev, Alexey V.; Tugaenko, Anton V.; Bogdanov, Artem S.; Perederiy, Anatoly N.; Spitsyn, Eugene M.

2014-06-01

A non-contact method for analyzing of explosives traces from surfaces was developed. The method is based on the laser desorption of analyzed molecules from the surveyed surfaces followed by the laser ionization of air sample combined with the field asymmetric ion mobility spectrometry (FAIMS). The pulsed radiation of the fourth harmonic of a portable GSGG: Cr3+ :Nd3+ laser (λ = 266 nm) is used. The laser desorption FAIMS analyzer have been developed. The detection limit of the analyzer equals 40 pg for TNT. The results of detection of trinitrotoluene (TNT), cyclotrimethylenetrinitramine (RDX) and cyclotetramethylenetetranitramine (HMX) are presented. It is shown that laser desorption of nitro-compounds from metals is accompanied by their surface decomposition. A method for detecting and analyzing of small concentrations of explosives in air based on the laser ionization and the FAIMS was developed. The method includes a highly efficient multipass optical scheme of the intracavity fourthharmonic generation of pulsed laser radiation (λ = 266 nm) and the field asymmetric ion mobility (FAIM) spectrometer disposed within a resonator. The ions formation and detection proceed inside a resonant cavity. The laser ion source based on the multi-passage of radiation at λ = 266 nm through the ionization region was elaborated. On the basis of the method the laser FAIMS analyzer has been created. The analyzer provides efficient detection of low concentrations of nitro-compounds in air and shows a detection limit of 10-14 - 10-15 g/cm3 both for RDX and TNT.

Nitramine Monopropellant Deflagration and General Nonsteady Reacting Rocket Chamber Flows.

Science.gov (United States)

1980-01-01

structure of RDX was also investigated by Harris,2 using X-ray diffraction. 2. The Crystalline Polymorphs of RMX HMX in the solid state exhibits four distinct...deflagration were shown to occur after transition . The critical transition pressure was found to correlate with the mean particle size of HMX and RDX ...Structure ....... ............ 4 2. The Crystalline Polymorphs of HMX ... ....... 5 3. Sublimation, Vaporization and Melting...... 6 C. The Chemical

Study of nano-nitramine explosives: preparation, sensitivity and application

Directory of Open Access Journals (Sweden)

Jie Liu

2014-06-01

Full Text Available Nano-nitramine explosives (RDX, HMX, CL-20 are produced on a bi-directional grinding mill. The scanning electron microscope (SEM observations show that the prepared particles are semi-spherical, and the narrow size distributions are characterized using the laser particle size analyzer. Compared with the micron-sized samples, the nano-products show obvious decrease in friction and impact sensitivities. In the case of shock sensitivities, nano-products have lower values by 59.9% (RDX, 56.4% (HMX, and 58.1% (CL-20, respectively. When nano-RDX and nano-HMX are used in plastic bonded explosives (PBX as alternative materials of micron-sized particles, their shock sensitivities are significantly decreased by 24.5% (RDX and 22.9% (HMX, and their detonation velocities are increased by about 1.7%. Therefore, it is expected to promote the application of nano-nitramine explosives in PBXs and composite modified double-based propellants (CMDBs so that some of their properties would be improved.

An Evaluation of the Environmental Fate and Behavior of Munitions Material (TNT, RDX) in Soil and Plant Systems. Environmental Fate and Behavior of RDX

Science.gov (United States)

1990-08-01

2.2 2.2 SOIL CHARACTERIZATION AND SAMPLING ............................................. 2.7 2.3 PLANT CULTIVATION ...cycle. 2.3 Plant Cultivation and Samoling The chemical fate of RDX in plants was evaluated using bush beans K (Phaseolus vulgaris), wheat (Triticum...particularly in light of the high tissue concentrations observed, may be important from the standpoint of food-chain transfer and ecotoxicology

Treatment of Explosives Residues From Range Activities

Science.gov (United States)

2010-01-01

total of 1200 lbs of crude soybean oil was purchased from Grain States Soya , Inc. (West Point, NE, USA) and shipped to the site in three 55 gal plastic...1.0E-08 1.0E-07 1.0E-06 1.0E-05 1.0E-04 1.0E-03 1.0E-02 1.0E-01 1.0E+00 0 1 2 3 4 5 6 7 Elapsed Time (years) Re la tiv e M as s Fl ux TNT RDX HMX...www.waupacasoilblenders.com Crude soybean oil suppliers Grain States Soya Inc. 400 Johnson Road West Point, NE 68788 Phone: 402-372-2429 Fax: 402-372-3305

Toxicity and uptake of cyclic nitramine explosives in ryegrass Lolium perenne

International Nuclear Information System (INIS)

Rocheleau, Sylvie; Lachance, Bernard; Kuperman, Roman G.; Hawari, Jalal; Thiboutot, Sonia; Ampleman, Guy; Sunahara, Geoffrey I.

2008-01-01

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) are cyclic nitramines used as explosives. Their ecotoxicities have been characterized incompletely and little is known about their accumulation potential in soil organisms. We assessed the toxicity and uptake of these explosives in perennial ryegrass Lolium perenne L. exposed in a Sassafras sandy loam (SSL) or in a sandy soil (DRDC, CL-20 only) containing contrasting clay contents (11% and 0.3%, respectively). A 21-d exposure to RDX, HMX or CL-20 in either soil had no adverse effects on ryegrass growth. RDX and HMX were translocated to ryegrass shoots, with bioconcentration factors (BCF) of up to 15 and 11, respectively. In contrast, CL-20 was taken up by the roots (BCF up to 19) with no translocation to the shoots. These studies showed that RDX, HMX, and CL-20 can accumulate in plants and may potentially pose a risk of biomagnification across the food chain. - Cyclic nitramine explosives accumulate in perennial ryegrass and exhibit distinct uptake patterns

Toxicity and uptake of cyclic nitramine explosives in ryegrass Lolium perenne

Energy Technology Data Exchange (ETDEWEB)

Rocheleau, Sylvie; Lachance, Bernard [Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2 (Canada); Kuperman, Roman G. [Edgewood Chemical Biological Center, 5183 Blackhawk Road, Aberdeen Proving Ground, MD 21010-5424 (United States); Hawari, Jalal [Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2 (Canada); Thiboutot, Sonia; Ampleman, Guy [Defense Research and Development Canada, 2459 Pie IX Boulevard, Val Belair, Quebec G3J 1X5 (Canada); Sunahara, Geoffrey I. [Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2 (Canada)], E-mail: geoffrey.sunahara@cnrc-nrc.gc.ca

2008-11-15

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) are cyclic nitramines used as explosives. Their ecotoxicities have been characterized incompletely and little is known about their accumulation potential in soil organisms. We assessed the toxicity and uptake of these explosives in perennial ryegrass Lolium perenne L. exposed in a Sassafras sandy loam (SSL) or in a sandy soil (DRDC, CL-20 only) containing contrasting clay contents (11% and 0.3%, respectively). A 21-d exposure to RDX, HMX or CL-20 in either soil had no adverse effects on ryegrass growth. RDX and HMX were translocated to ryegrass shoots, with bioconcentration factors (BCF) of up to 15 and 11, respectively. In contrast, CL-20 was taken up by the roots (BCF up to 19) with no translocation to the shoots. These studies showed that RDX, HMX, and CL-20 can accumulate in plants and may potentially pose a risk of biomagnification across the food chain. - Cyclic nitramine explosives accumulate in perennial ryegrass and exhibit distinct uptake patterns.

Molten salt destruction as an alternative to open burning of energetic material wastes

International Nuclear Information System (INIS)

Upadhye, R.S.; Watkins, B.E.; Pruneda, C.O.; Brummond, W.A.

1994-01-01

LLNL has built a small-scale (about 1 kg/hr throughput unit to test the destruction of energetic materials using the Molten Salt Destruction (MSD) process. We have modified the unit described in the earlier references to inject energetic waste material continuously into the unit. In addition to the HMX, other explosives we have destroyed include RDX, PETN, ammonium picrate, TNT, nitroguanadine, and TATB. We have also destroyed a liquid gun propellant comprising hydroxyl ammonium nitrate, triethanolammonium nitrate and water. In addition to these pure components, we have destroyed a number of commonly used formulations, such as LX-10 (HMX/Viton), LX-16 (PETN/FPC461, LX-17 (TATB/Kel F), and PBX-9404 (HMX)/CEF/Nitro cellulose). Our experiments have demonstrated that energetic materials can be safely and effectively treated by MSD.We have also investigated the issue of steam explosions in molten salt units, both experimentally and theoretically, and concluded that steam explosions can be avoided under proper design and operating conditions. We are currently building a larger unit (nominal capacity 5 kg/hr,) to investigate the relationship between residence time, temperature, feed concentration and throughputs, avoidance of back-burn, a;nd determination of the products of combustion under different operating conditions

Explosives and chemical warfare agents - detection and analysis with PTR-MS

Energy Technology Data Exchange (ETDEWEB)

Sulzer, Philipp; Juerschik, Simone; Jaksch, Stefan; Jordan, Alfons; Hanel, Gernot; Hartungen, Eugen; Seehauser, Hans; Maerk, Lukas; Haidacher, Stefan; Schottkowsky, Ralf [IONICON Analytik GmbH, Innsbruck (Austria); Petersson, Fredrik [Institut fuer Ionenphysik und Angewandte Physik, Leopold-Franzens Universitaet Innsbruck (Austria); Maerk, Tilmann [IONICON Analytik GmbH, Innsbruck (Austria); Institut fuer Ionenphysik und Angewandte Physik, Leopold-Franzens Universitaet Innsbruck (Austria)

2010-07-01

We utilized a recently developed high sensitivity PTR-MS instrument equipped with a high resolution time-of-flight mass analyzer for detailed investigations on explosives and chemical warfare agents (CWAs). We show that with this so called PTR-TOF 8000 it is possible to identify solid explosives (RDX, TNT, HMX, PETN and Semtex A) by analyzing the headspace above small quantities of samples at room temperature and from trace quantities not visible to the naked eye placed on surfaces. As the mentioned solid explosives possess very low vapor pressures, the main challenge for detecting them in the gas phase is to provide an instrument with a sufficient sensitivity. CWAs on the other side have very high vapor pressures but are difficult to identify unambiguously as their nominal molecular masses are usually comparably small and therefore hard to distinguish from harmless everyday-compounds (e.g. mustard gas: 159 g/mol). In the present work we demonstrate that we can detect a broad range of dangerous substances, ranging from the CWA mustard gas to the explosive HMX.

Effectiveness of laser sources for contactless sampling of explosives

Science.gov (United States)

Akmalov, Artem E.; Chistyakov, Alexander A.; Kotkovskii, Gennadii E.

2016-05-01

A mass-spectrometric study of photo processes initiated by ultraviolet (UV) laser radiation in explosives adsorbed on metal and dielectric substrates has been performed. A calibrated quadrupole mass spectrometer was used to determine a value of activation energy of desorption and a quantity of explosives desorbed by laser radiation. A special vacuumoptical module was elaborated and integrated into a vacuum mass-spectrometric system to focus the laser beam on a sample. It has been shown that the action of nanosecond laser radiation set at q= 107 - 108 W/cm2, λ=266 nm on adsorbed layers of molecules of trinitrotoluene (TNT ) and pentaerytritoltetranitrate (PETN) leads not only to an effective desorption, but also to the non-equilibrium dissociation of molecules with the formation of nitrogen oxide NO. The cyclotrimethylenetrinitramine (RDX) dissociation products are observed only at high laser intensities (q> 109 W/cm2) thus indicating the thermal nature of dissociation, whereas desorption of RDX is observed even at q> 107 W/cm2 from all substrates. Desorption is not observed for cyclotetramethylenetetranitramine (HMX) under single pulse action: the dissociation products NO and NO2 are registered only, whereas irradiation at 10Hz is quite effective for HMX desorption. The results clearly demonstrate a high efficiency of nanosecond laser radiation with λ = 266 nm, q ~ 107 - 108 W/cm2, Epulse= 1mJ for desorption of molecules of explosives from various surfaces.

Exploring the High-Pressure Behavior of PETN: A Combined Quantum Mechanical and Experimental Study

Science.gov (United States)

2006-11-01

calculations to explore the hypothesized compression-induced polymorphic phase transition [Gruzdkov 2004]. The initial crystal in these Figure 4...Scuseria, G.E., and Chabalowski, C.F. 2004: An ab Initio Study of Solid Nitromethane, HMX , RDX , and CL20: Successes and Failures of DFT. J. Phys. Chem... RDX , HMX , HNIW, and PETN Crystals. J. Phys. Chem. B, 103, 6783. Trotter, J., 1963: Bond lengths and angles in Pentaerythritol Tetranitrate. Acta

Multianalyte detection using a capillary-based flow immunosensor.

Science.gov (United States)

Narang, U; Gauger, P R; Kusterbeck, A W; Ligler, F S

1998-01-01

A highly sensitive, dual-analyte detection system using capillary-based immunosensors has been designed for explosive detection. This model system consists of two capillaries, one coated with antibodies specific for 2,4,6-trinitrotoluene (TNT) and the other specific for hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) combined into a single device. The fused silica capillaries are prepared by coating anti-TNT and anti-RDX antibodies onto the silanized inner walls using a hetero-bifunctional crosslinker. After immobilization, the antibodies are saturated with a suitable fluorophorelabeled antigen. A "T" connector is used to continuously flow the buffer solution through the individual capillaries. To perform the assay, an aliquot of TNT or RDX or a mixture of the two analytes is injected into the continuous flow stream. In each capillary, the target analyte displaces the fluorophore-labeled antigen from the binding pocket of the antibody. The labeled antigen displaced from either capillary is detected downstream using two portable spectrofluorometers. The limits of detection for TNT and RDX in the multi-analyte formate are 44 fmol (100 microliters of 0.1 ng/ml TNT solution) and 224 fmol (100 microliters of 0.5 ng/ml RDX solution), respectively. The entire assay for both analytes can be performed in less than 3 min.

Unreacted equation of states of typical energetic materials under static compression: A review

International Nuclear Information System (INIS)

Zheng Zhaoyang; Zhao Jijun

2016-01-01

The unreacted equation of state (EOS) of energetic materials is an important thermodynamic relationship to characterize their high pressure behaviors and has practical importance. The previous experimental and theoretical works on the equation of state of several energetic materials including nitromethane, 1,3,5-trinitrohexahydro-1,3,5-triazine (RDX), 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane (HMX), hexanitrostilbene (HNS), hexanitrohexaazaisowurtzitane (HNIW or CL-20), pentaerythritol tetranitrate (PETN), 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105), triamino-trinitrobenzene (TATB), 1,1-diamino-2,2-dinitroethene (DADNE or FOX-7), and trinitrotoluene (TNT) are reviewed in this paper. The EOS determined from hydrostatic and non-hydrostatic compressions are discussed and compared. The theoretical results based on ab initio calculations are summarized and compared with the experimental data. (topical review)

Preparation and characterization of GA/RDX nanostructured ...

Indian Academy of Sciences (India)

Thenhexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was added and trapped in the nano-porous three-dimensional networks of GA to obtain a novel GA/RDX nanostructured energetic composite. The composition, morphology andstructure of the obtained GA/RDX nanostructured energetic composite were characterized by ...

Development of Biomarkers for Assessing In Situ RDX Biodegradation Potential

Science.gov (United States)

2016-06-10

the RDX degrading communities in four different soil slurries. The third task examined the microorganisms involved in RDX biodegradation from...RDX biodegradation at two Navy sites. Several key microorganisms were associated with RDX removal in these mixed communities. These phylogenetic and...manuscripts. 1 ABSTRACT Objective The objective was to identify the microorganisms and genes responsible for the biodegradation of RDX (hexahydro

Initial characterization of a highly contaminated high explosives outfall in preparation for in situ bioremediation

Energy Technology Data Exchange (ETDEWEB)

Betty A. Strietelmeier; Patrick J. Coyne; Patricia A. Leonard; W. Lamar Miller; Jerry R. Brian

1999-12-01

In situ bioremediation is a viable, cost-effective treatment for environmental contamination of many kinds. The feasibility of using biological techniques to remediate soils contaminated with high explosives (HE) requires laboratory evaluation before proceeding to a larger scale field operation. Laboratory investigations have been conducted at pilot scale which indicate that an anaerobic process could be successful at reducing levels of HE, primarily HMX, RDX and TNT, in contaminated soils. A field demonstration project has been designed to create an anaerobic environment for the degradation of HE materials. The first step in this project, initial characterization of the test area, was conducted and is the subject of this report. The levels of HE compounds found in the samples from the test area were higher than the EPA Method 8330 was able to extract without subsequent re-precipitation; therefore, a new method was developed using a superior extractant system. The test area sampling design was relatively simple as one might expect in an initial characterization. A total of 60 samples were each removed to a depth of 4 inches using a 1 inch diameter corer. The samples were spaced at relatively even intervals across a 20 foot cross-section through the middle of four 7-foot-long adjacent plots which are designed to be a part of an in situ bioremediation experiment. Duplicate cores were taken from each location for HE extraction and analysis in order to demonstrate and measure the heterogeneity of the contamination. Each soil sample was air dried and ball-milled to provide a homogeneous solid for extraction and analysis. Several samples had large consolidated pieces of what appeared to be solid HE. These were not ball-milled due to safety concerns, but were dissolved and the solutions were analyzed. The new extraction method was superior in that results obtained for several of the contaminants were up to 20 times those obtained with the EPA extraction method. The

Electrostaticspray preparation and properties of RDX/DOS composites

Directory of Open Access Journals (Sweden)

Jian Yao

2017-08-01

Full Text Available A composite explosive based on 1, 3, 5-trinitro-1, 3, 5-triazinane (RDX was prepared by electrostaticspray method with dioctyl sebacate (DOS as desensitizer. After preparation, the particle size and crystal structure were characterized and chemical features, such as chemical bonds, functional groups, thermal decomposition parameters and mechanical sensitivity were investigated as well. In terms of the morphologies of the composites, the particle sizes were in the range of 1–3 μm. Compared with RDX, the crystal types, chemical bonds and functional groups of the RDX/DOS composites were unchanged. The activation energy of the composites was lower than that of raw RDX, and the 3wt % DOS composites had the lowest activation energy. The impact sensitivity and friction sensitivity of the RDX/DOS composites were lower than those of raw RDX, and the 10wt% DOS composites had the highest H50 (125.9 cm and the lowest friction sensitivity (8%.

Workshop Report: Fundamental Reactions in Solid Propellant Combustion

Science.gov (United States)

1979-05-01

combustion conditions. 6. What effect might a pressure-induced phase transition to a polymorph other than 6- HMX have on the pressure slope break during...pure HMX as well. Nevertheless, it is recommended that the high pressure polymorphs of HMX and RDX be determined. It was also felt that there...plateau burning phenomena E. Solid phase, surface, gas phase reactions F. Phase transitions : melting, vaporization, polymorphs G. Flame

Comparative analysis of the vapor headspace of military-grade TNT versus NESTT TNT under dynamic and static conditions

Science.gov (United States)

Edge, Cindy C.; Gibb, Julie; Wasserzug, Louis S.

1998-09-01

The Institute for Biological Detection Systems (IBDS) has developed a quantitative vapor delivery system that can aid in characterizing dog's sensitivity and ability to recognize odor signatures for explosives and contraband substances. Determining of the dog's odor signature for detection of explosives is important because it may aid in eliminating the risk of handling explosives and reducing cross-contamination. Progress is being made in the development of training aids that represent the headspace of the explosives. NESTTTM TNT materials have been proposed as an approach to developing training aid simulates. In order for such aids to be effective they must mimic the headspace of the target material. This study evaluates the NESTTTM TNT product with regard to this criterion. NESTTTM TNT vapor was generated by the IBDS vapor delivery system, which incorporates a vapor generation cell that enables the user to control the conditions under which a substance is tested. The NESTTTM TNT vapor was compared to the headspace of military-grade TNT. The findings identify and quantify major vapor constituents of military-grade TNT and NESTTTM TNT. A comparative analysis evaluated the degree to which the NESTTTM TNT mimics the headspace of an actual TNT sample.

Application of 13C-stable isotope probing to identify RDX-degrading microorganisms in groundwater

International Nuclear Information System (INIS)

Cho, Kun-Ching; Lee, Do Gyun; Roh, HyungKeun; Fuller, Mark E.; Hatzinger, Paul B.; Chu, Kung-Hui

2013-01-01

We employed stable isotope probing (SIP) with 13 C-labeled hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) to identify active microorganisms responsible for RDX biodegradation in groundwater microcosms. Sixteen different 16S rRNA gene sequences were derived from microcosms receiving 13 C-labeled RDX, suggesting the presence of microorganisms able to incorporate carbon from RDX or its breakdown products. The clones, residing in Bacteroidia, Clostridia, α-, β- and δ-Proteobacteria, and Spirochaetes, were different from previously described RDX degraders. A parallel set of microcosms was amended with cheese whey and RDX to evaluate the influence of this co-substrate on the RDX-degrading microbial community. Cheese whey stimulated RDX biotransformation, altered the types of RDX-degrading bacteria, and decreased microbial community diversity. Results of this study suggest that RDX-degrading microorganisms in groundwater are more phylogenetically diverse than what has been inferred from studies with RDX-degrading isolates. Highlights: •SIP identified sixteen groundwater bacteria capable of using RDX and/or its metabolites as a carbon source. •The RDX degraders in groundwater are phylogenetically diverse and different from known RDX degraders. •Cheese whey induced community shift and altered diversity of the RDX-degrading microorganisms over time. -- RDX-degrading bacteria in contaminated groundwater, identified by SIP with 13 C-labeled RDX, are phylogenetically diverse and different from known RDX degraders

Negative Ion Formation of Pentaerythritol Tetranitrate in Atmospheric Pressure Chemical Ionization-Mass Spectrometry and in Corona Discharge Ionization-Ion Mobility Spectrometry

International Nuclear Information System (INIS)

Choi, Sung Seen; Kim, Ok Bae; Kim, Yun Ki; An, Seung Geon; Shin, Myung Won; Maeng, Seug Jin; Choi, Gyu Seop

2011-01-01

Most organic explosives contain nitro groups and are subdivided into nitro-aromatic compounds, nitrate esters, and nitroamines. 1,3,5-Trinitrobenzene (TNB), 2,4,6-trinitrotoluene (TNT), and 2,4-dinitrotoluene (DNT) belong to the nitroaromatic compounds, pentaerythritol tetranitrate (PETN) is one of the nitrate esters, and the nitroamines include 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). Explosives are unstable compounds and their polarities vary from moderate to high due to their nitro groups. These properties impose certain limitations on techniques used for their analysis, since explosives may decompose during analysis or result in poor chromatographic retention. Gas chromatography (GC) is suitable for the analysis of nitroaromatic compounds, but not for nitrate esters and nitroamines, which undergo thermal decomposition under the high temperature conditions of injector and oven. High-performance liquid chromatography (HPLC) would be a better alternative for the more unstable and polar explosives Common analytical

Preparation and Characterization of the Solid Spherical HMX/F2602 by the Suspension Spray-Drying Method

Science.gov (United States)

Ji, Wei; Li, Xiaodong; Wang, Jingyu; Ye, Baoyun; Wang, Cailing

2016-10-01

Solid spherical octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine/fluororubber2602 (HMX/F2602) was prepared by the suspension spray-drying method as follows: firstly, thinning octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) was obtained by a solvent-anti-solvent method. Secondly, thinning HMX suspended in ethyl acetate solvent in a solution of a binder-F2602-was made into a suspension. Finally, the samples were prepared by spray drying. The samples were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectrometry (XPS), X-ray diffraction (XRD), and Fourier transform infrared (FTIR), and its thermal stability as well as mechanical and spark sensitivities were measured. The results of SEM showed that the grain of HMX/F2602 was solid spherical and the particle distribution was homogeneous. The results of XPS indicated that F2602 can be successfully coated on the surface of HMX crystals. Compared to raw HMX, th characteristic drop height was increased from 19.60 to 40.37 cm, an increase of 79.10%. The friction sensitivities of HMX reduced from 100 to 28% and the spark sensitivity of HMX/F2602 increased. The critical explosion temperatures of raw HMX and HMX/F2602 were 275.43 and 274.30°C, respectively. The amount of gas evolution of raw HMX and HMX/F2602 was 0.15 and 0.12 ml.(5 g)-1, respectively. The results of DSC and vacuum stability tests (VSTs) indicate that the thermal stability of HMX/F2602 was equal to that of raw HMX and HMX and F2602 had good compatibility.

Anaerobic and aerobic transformation of TNT

Energy Technology Data Exchange (ETDEWEB)

Kulpa, C.F. [Univ. of Notre Dame, IN (United States). Dept. of Biological Sciences; Boopathy, R.; Manning, J. [Argonne National Lab., IL (United States). Environmental Research Div.

1996-12-31

Most studies on the microbial metabolism of nitroaromatic compounds have used pure cultures of aerobic microorganisms. In many cases, attempts to degrade nitroaromatics under aerobic conditions by pure cultures result in no mineralization and only superficial modifications of the structure. However, mixed culture systems properly operated result in the transformation of 2,4,6-trinitrotoluene (TNT) and in some cases mineralization of TNT occurs. In this paper, the mixed culture system is described with emphasis on intermediates and the characteristics of the aerobic microbial process including the necessity for a co-substrate. The possibility of removing TNT under aerobic/anoxic conditions is described in detail. Another option for the biodegradation of TNT and nitroaromatics is under anaerobic, sulfate reducing conditions. In this instance, the nitroaromatic compounds undergo a series of reductions with the formation of amino compounds. TNT under sulfate reducing conditions is reduced to triaminotoluene presumably by the enzyme nitrite reductase, which is commonly found in many Desulfovibrio spp. The removal of nitro groups from TNT is achieved by a series of reductive reactions with the formation of ammonia and toluene by Desulfovibrio sp. (B strain). These metabolic processes could be applied to other nitroaromatic compounds like nitrobenzene, nitrobenzoic acids, nitrophenols, and aniline. The data supporting the anaerobic transformation of TNT under different growth condition are reviewed in this report.

Burning rate characteristics of energetic CMDB propellants. Part 2. Effect of HMX addition; Ko enerugi CMDB suishin yaku no nensho sokudo tokusei ( II ) - HMX tenka no koka -

Energy Technology Data Exchange (ETDEWEB)

Aoki, I. [Nissan Motor Co. Ltd. (Japan)

1997-08-01

Burning rate and specific impulse of a solid propellant are extremely important parameters in a design of a solid rocket motor. In this study, the relations between the burning rate and the amount of energy contained in HMX-CMDB propellants wherein the amount of energy is varied by adding HMX (High Melting Point Explosive). The following results are obtained. The final flame temperature is getting higher when the amount of energy is increased by adding HMX into a double-base propellant. The higher the final flame temperature is, the lower the burning rate is. Dark zone temperature, as a physical property, is lowered when the containing amount of energy is increased by adding HMX into the double-base propellant. This is because that, when weight fraction of HMX is increased, reaction heat at burning surface decreases, and the reaction in fizz zone is getting slower. The higher the dark zone temperature is, the higher the burning rate is. 20 refs., 11 figs., 1 tab.

Modeling solid thermal explosion containment on reactor HNIW and HMX

International Nuclear Information System (INIS)

Lin, Chun-Ping; Chang, Chang-Ping; Chou, Yu-Chuan; Chu, Yung-Chuan; Shu, Chi-Min

2010-01-01

2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaaza-isowurtzitane (HNIW), also known as CL-20 and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), are highly energetic materials which have been popular in national defense industries for years. This study established the models of thermal decomposition and thermal explosion hazard for HNIW and HMX. Differential scanning calorimetry (DSC) data were used for parameters determination of the thermokinetic models, and then these models were employed for simulation of thermal explosion in a 437 L barrel reactor and a 24 kg cubic box package. Experimental results indicating the best storage conditions to avoid any violent runaway reaction of HNIW and HMX were also discovered. This study also developed an efficient procedure regarding creation of thermokinetics and assessment of thermal hazards of HNIW and HMX that could be applied to ensure safe storage conditions.

The Evolution of Sensitivity in Hmx-Based Explosives during the Reversion from Delta to Beta Phase

Science.gov (United States)

Peterson, P. D.; Lee, K.-Y.; Moore, D. S.; Scharff, R. J.; Avilucea, G. R.

2007-12-01

In an effort to better understand the evolution of sensitivity in HMX-based explosives formulations during the reversion from the delta to the beta polymorph, we have performed friction and impact experiments on Class 1 (coarse) and Class 2 (fine) HMX [1]. Initial baselines for Type 12 drop weight impact and BAM friction sensitivities were obtained for the β-HMX starting material. The HMX was then heated at ˜184 °C for 14 h. Raman spectroscopy was used to confirm the conversion to delta-phase. Raman results show that the δ material remains δ for long periods when stored in a dessicator at room temperature (RT), converts to alpha when stored at RT and 20-40% relative humidity (RH) over a period of days, and reverts to beta over a period of days when stored at RT and 95-98% relative humidity (RH). Impact and friction tests were performed on the δ-HMX, converted α-HMX, and reverted β-HMX. The tests show similar sensitivities of the δ-HMX and converted α-HMX in both impact and friction, both of which are ˜10-20% more sensitive than the β-HMX and reverted beta depending on the particle size distribution. The α-HMX appears to be fairly stable over time (by Raman analysis) at ambient conditions, but fairly low humidity (20-40%), or in a dessicator.

Surfactant producing TNT-degrading microorganisms for bioremediation

Energy Technology Data Exchange (ETDEWEB)

Vorobyov, A.; Marchenko, A.; Rudneva, O.; Borovick, R. [Research Center for Toxicology and Hygienic Regulation of Biopreparations, Serpukhov, Moscow region (Russian Federation); Radosevich, M. [Univ. of Delaware, Newark (United States). Dept. of Plant and Soil Sciences

2003-07-01

In general the biodegradation of nitroaromatic hydrocarbons is influenced by their bioavailability. 2,4,6-trinitrotoluene is very poorly soluble in water. TNT is easily adsorbed to clay or humus fractions in the soil, and pass very slowly to the aqueous phase, where microorganisms metabolize it. Biosurfactants that increase TNT solubility and improve its bioavailability can thereby accelerate degradation. Pure cultures of microorganisms-TNT degraders were isolated by the method of enrichment cultures from samples of different-type soil contaminated by TNT (soddy-podzol, black earth, and gray forest ones). From 28 soil samples 35 isolates of microorganisms degrading TNT were taken. The isolated soil samples had been tested for availability of microbial activity towards TNT. By10 g of air-dried soil, 10 ml of distilled water, and 2 mg of TNT were placed into 750 ml shaken flasks. The flasks were incubated at 150 rev/min and 24 C. Glucose, sodium succinate or sodium acetate had been used as co-substrates. The ability of the strains to produce surfactants was studied by drop collapsing test and direct measuring of surface tension of cultural liquid after cultivation with TNT. Cells of the strains were cultivated on solid and liquid nutrient media. For drop collapsing test the cells were cultivated on solid nutrient media; the separated colonies were suspended in distilled water. Drop sustainability test ws conducted on a standard 96-well plates coated with a thin layer of vaseline oil. Surface tension of cultural liquid ws measured after cultivation of strains in the presence of TNT with the use of a ring tensiometer. Before measuring of surface tension microbial cells were collected from liquid culture by centrifugation. (orig.)

Reverse Phase HPLC Method for Analysis of TNT, RDX, HMX and 2,4-DNT in Munitions Wastewater,

Science.gov (United States)

1984-12-01

Materials Agency (USATHAMA), Capt. P. Rissell (USATHAMA) and Dr. R. Westerdahl (LCWSL). project monitors. The authors ac- knowledge the support given by...Capt. Rissell and Dr. Westerdahl throughout this effort, and their technical review of the report. The contents of this report are not to be used for

Analysis of RDX and RDX Breakdown Products in Environmental Samples

Energy Technology Data Exchange (ETDEWEB)

Felt, Deborah R.; Larson, Steven L.; Wani, Altaf; Davis, Jeffrey L.

2003-03-26

The identification and quantification of explosives and their degradation products in soil and natural waters is helpful in the design of remediation technologies, mobility investigations and performing risk assessments. The objective of this study was to develop a method for the determination of the degradation of nitramine compounds, specifically hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). The analytical methods developed in this study were based on reversed-phase high performance liquid chromatography (HPLC) using both C-18 and CN bonded silica columns to eliminate common interferences. Contaminant identification was further confirmed by performing spectral analysis of the compounds upon elution. The proposed method yields good separation of RDX from its degradation products and from other common energetic compounds. Method detection limits for the proposed method ranged from 0.01 to 0.03 mg/L. This method satisfies the need for analytical techniques to monitor the formation and subsequent degradation products of toxic and carcinogenic nitrosyl substituted nitramines.

Impacts of explosive compounds on vegetation: A need for community scale investigations

International Nuclear Information System (INIS)

Via, Stephen M.; Zinnert, Julie C.

2016-01-01

Explosive compounds are distributed heterogeneously across the globe as a result of over a century of human industrial and military activity. RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and TNT (2-methyl-1,3,5-trinitrobenzene) are the most common and most abundant explosives in the environment. Vegetation exhibits numerous physiological and morphological stress responses in the presence of RDX and TNT. Varied stress responses act as physiological filters that facilitate the proliferation of tolerant species and the extirpation of intolerant species. Contaminants alter community composition as they differentially impact plants at each life stage (i.e. germination, juvenile, adult), subsequently modifying larger scale ecosystem processes. This review summarizes the current explosives-vegetation literature, focusing on RDX and TNT as these are well documented in the literature, linking our current understanding to ecological theory. A conceptual framework is provided that will aid future efforts in predicting plant community response to residual explosive compounds. - Highlights: • There is a strong need for community scale explosives research. • Contaminants alter community composition as they impact plants at each life stage. • These small scale changes modify larger scale ecosystem processes. • This review summarizes the current explosives-vegetation literature. • We focus on RDX and TNT as these are well documented in the literature. - Explosives act as physiological filters that alter community composition as they differentially affect plants at each life stage (i.e. germination, juvenile, adult).

Effect of Nano-Magnesium Hydride on the Thermal Decomposition Behaviors of RDX

International Nuclear Information System (INIS)

Yao, M.; Chen, L.; Rao, G.; Peng, J.; Zou, J.; Zeng, X.

2013-01-01

In order to improve the detonation performance of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) explosive, addictive with high heat values were used, and magnesium hydride (MgH 2 ) is one of the candidates. However, it is important to see whether MgH 2 is a safe addictive. In this paper, the thermal and kinetic properties of RDX and mixture of RDX/MgH 2 were investigated by differential scanning calorimeter (DSC) and accelerating rate calorimeter (ARC), respectively. The apparent activation energy (E) and frequency factor (A) of thermal explosion were calculated based on the data of DSC experiments using the Kissinger and Ozawa approaches. The results show that the addition of MgH 2 decreases both E and A of RDX, which means that the mixture of RDX/MgH 2 has a lower thermal stability than RDX, and the calculation results obtained from the ARC experiments data support this too. Besides, the most probable mechanism functions about the decomposition of RDX and RDX/MgH 2 were given in this paper which confirmed the change of the decomposition mechanism.

Nano-CL-20/HMX Cocrystal Explosive for Significantly Reduced Mechanical Sensitivity

Directory of Open Access Journals (Sweden)

Chongwei An

2017-01-01

Full Text Available Spray drying method was used to prepare cocrystals of hexanitrohexaazaisowurtzitane (CL-20 and cyclotetramethylene tetranitramine (HMX. Raw materials and cocrystals were characterized using scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, Raman spectroscopy, and Fourier transform infrared spectroscopy. Impact and friction sensitivity of cocrystals were tested and analyzed. Results show that, after preparation by spray drying method, microparticles were spherical in shape and 0.5–5 µm in size. Particles formed aggregates of numerous tiny plate-like cocrystals, whereas CL-20/HMX cocrystals had thicknesses of below 100 nm. Cocrystals were formed by C–H⋯O bonding between –NO2 (CL-20 and –CH2– (HMX. Nanococrystal explosives exhibited drop height of 47.3 cm, and friction demonstrated explosion probability of 64%. Compared with raw HMX, cocrystals displayed significantly reduced mechanical sensitivity.

Microbiological sanitation of abandoned armament sites - treatment of TNT-contaminated soils. Sanierung von Ruestungsaltlasten durch mikrobiologische Verfahren: Behandlung TNT-kontaminierter Boeden

Energy Technology Data Exchange (ETDEWEB)

Winterberg, R.; Stoffers, H. (Contracon GmbH, Cuxhaven (Germany))

TNT (trinitrotoluene) is the most commonly used military explosive. It is a hazardous material which has been spread over many abandoned armament sites since its production and processing during Wold War II and the subsequent delaboration and dismantling of TNT production plants. The harmful effect of this explosive on man and on the environment calls for the sanitation of TNT-contaminated sites. The microbiological method is among the techniques applied to clean TNT-contaminated soils and waters. (orig.).

Biodegradation of TNT (2,4,6-Trinitrotoluene) by Phanerochaete chrysosporium

International Nuclear Information System (INIS)

Fernando, T.; Bumpus, J.A.; Aust, S.D.

1990-01-01

Extensive biodegradation of TNT (2,4,6-trinitrotoluene) by the white rot fungus Phanerochaete chrysosporium was observed. At an initial concentration of 1.3 mg/liter, 35.4 ± 3.6% of the [ 14 C]TNT was degraded to 14 CO 2 in 18 days. The addition of glucose 12 days after the addition of TNT did not stimulate mineralization, and, after 18 days of incubation with TNT only, about 3.3% of the initial TNT could be recovered. Mineralization of [ 14 C]TNT absorbed on soil was also examined. Ground corncobs served as the nutrient for slow but sustained degradation of [ 14 C]TNT to 14 CO 2 such that 6.3 ± 0.6% of the [ 14 C]TNT initially present was converted to 14 CO 2 during the 30-day incubation period. Mass balance analysis of liquid cultures and of soil-corncob cultures revealed that polar [ 14 C]TNT metabolites are formed in both systems, and high-performance liquid chromatography analyses revealed that less then 5% of the radioactivity remained as undegraded [ 14 C]TNT following incubation with the fungus in soil and liquid cultures. When the concentration of TNT in cultures (both liquid and soil) was adjusted to contamination levels that might be found in the environment, i.e., 10,000 mg/kg in soil and 100 mg/liter in water, mineralization studies showed that 18.4 ± 2.9% and 19.6 ± 3.5% of the initial TNT was converted to 14 CO 2 in 90 days in soil and liquid cultures, respectively. In both cases (90 days in water at 100 mg/liter and in soil at 10,000 mg/kg) approximately 85% of the TNT was degraded. These results suggest that this fungus may be useful for the decontamination of sites in the environment contaminated with TNT

Isotopic measurements (C,N,O) of detonation soot produced from labeled and unlabeled Composition B-3 indicate source of solid carbon residues

Science.gov (United States)

Podlesak, David; Manner, Virginia; Amato, Ronald; Dattelbaum, Dana; Gusavsen, Richard; Huber, Rachel

2017-06-01

Detonation of HE is an exothermic process whereby metastable complex molecules are converted to simple stable molecules such as H2 O, N2, CO, CO2, and solid carbon. The solid carbon contains various allotropes such as detonation nanodiamonds, graphite, and amorphous carbon. It is well known that certain HE formulations such as Composition B (60% RDX, 40% TNT) produce greater amounts of solid carbon than other more oxygen-balanced formulations. To develop a greater understanding of how formulation and environment influence solid carbon formation, we synthesized TNT and RDX with 13 C and 15 N at levels slightly above natural abundance levels. Synthesized RDX and TNT were mixed at a ratio of 60:40 to form Composition B and solid carbon residues were collected from detonations of isotopically-labeled as well as un-labelled Composition B. The raw HE and detonation residues were analyzed isotopically for C, N, O isotopic compositions. We will discuss differences between treatments groups as a function of formulation and environment. LA-UR - 17-21266.

Identification of groundwater microorganisms capable of assimilating RDX-derived nitrogen during in-situ bioremediation

Energy Technology Data Exchange (ETDEWEB)

Cho, Kun-Ching [Zachry Department of Civil Engineering, Texas A& M University, College Station, TX 77843-3136 (United States); Fuller, Mark E.; Hatzinger, Paul B. [CB& I Federal Services, Lawrenceville, NJ 08648 (United States); Chu, Kung-Hui, E-mail: kchu@civil.tamu.edu [Zachry Department of Civil Engineering, Texas A& M University, College Station, TX 77843-3136 (United States)

2016-11-01

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), a nitroamine explosive, is commonly detected in groundwater at military testing and training sites. The objective of this study was to characterize the microbial community capable of using nitrogen derived from the RDX or RDX intermediates during in situ bioremediation. Active groundwater microorganisms capable of utilizing nitro-, ring- or fully-labeled {sup 15}N-RDX as a nitrogen source were identified using stable isotope probing (SIP) in groundwater microcosms prepared from two wells in an aquifer previously amended with cheese whey to promote RDX biodegradation. A total of fifteen 16S rRNA gene sequences, clustered in Clostridia, β-Proteobacteria, and Spirochaetes, were derived from the {sup 15}N-labeled DNA fractions, suggesting the presence of metabolically active bacteria capable of using RDX and/or RDX intermediates as a nitrogen source. None of the derived sequences matched RDX-degrading cultures commonly studied in the laboratory, but some of these genera have previously been linked to RDX degradation in site groundwater via {sup 13}C-SIP. When additional cheese whey was added to the groundwater samples, 28 sequences grouped into Bacteroidia, Bacilli, and α-, β-, and γ-Proteobacteria were identified. The data suggest that numerous bacteria are capable of incorporating N from ring- and nitro-groups in RDX during anaerobic bioremediation, and that some genera may be involved in both C and N incorporation from RDX. - Highlights: • Cheese whey addition resulted in 28 different clones associated with RDX degradation. • The 28 clones belong to Bacteroidia, Bacilli, and α-, β-, and γ-Proteobacteria. • SIP identified 15 clones using RDX and/or its metabolites as a nitrogen source. • The clones clustered in Clostridia, β-Proteobacteria, and Spirochaetes.

Identification of groundwater microorganisms capable of assimilating RDX-derived nitrogen during in-situ bioremediation

International Nuclear Information System (INIS)

Cho, Kun-Ching; Fuller, Mark E.; Hatzinger, Paul B.; Chu, Kung-Hui

2016-01-01

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), a nitroamine explosive, is commonly detected in groundwater at military testing and training sites. The objective of this study was to characterize the microbial community capable of using nitrogen derived from the RDX or RDX intermediates during in situ bioremediation. Active groundwater microorganisms capable of utilizing nitro-, ring- or fully-labeled "1"5N-RDX as a nitrogen source were identified using stable isotope probing (SIP) in groundwater microcosms prepared from two wells in an aquifer previously amended with cheese whey to promote RDX biodegradation. A total of fifteen 16S rRNA gene sequences, clustered in Clostridia, β-Proteobacteria, and Spirochaetes, were derived from the "1"5N-labeled DNA fractions, suggesting the presence of metabolically active bacteria capable of using RDX and/or RDX intermediates as a nitrogen source. None of the derived sequences matched RDX-degrading cultures commonly studied in the laboratory, but some of these genera have previously been linked to RDX degradation in site groundwater via "1"3C-SIP. When additional cheese whey was added to the groundwater samples, 28 sequences grouped into Bacteroidia, Bacilli, and α-, β-, and γ-Proteobacteria were identified. The data suggest that numerous bacteria are capable of incorporating N from ring- and nitro-groups in RDX during anaerobic bioremediation, and that some genera may be involved in both C and N incorporation from RDX. - Highlights: • Cheese whey addition resulted in 28 different clones associated with RDX degradation. • The 28 clones belong to Bacteroidia, Bacilli, and α-, β-, and γ-Proteobacteria. • SIP identified 15 clones using RDX and/or its metabolites as a nitrogen source. • The clones clustered in Clostridia, β-Proteobacteria, and Spirochaetes

RDX Detection with THz Spectroscopy

Science.gov (United States)

Michalopoulou, Zoi-Heleni; Mukherjee, Suman; Hor, Yew Li; Su, Ke; Liu, Zhiwei; Barat, Robert B.; Gary, Dale E.; Federici, John F.

2010-10-01

Spectroscopic analysis in the Terahertz frequency range, providing characteristic “signatures” for explosive and non-explosive materials, is proposed as an efficient and powerful tool for explosive identification. It is demonstrated that spectral responses of materials can be used as fingerprints that distinguish cyclotrimethylenetrinitramine (RDX) from other materials even with simple detectors and a limited number of available frequencies. Detection is performed using a modified least squares approach and multilayer perceptrons that operate on smoothed reflectance spectra. The performance of the detectors is evaluated through application to spectra of RDX and several common materials. A Receiver Operating Characteristic curve analysis demonstrates that our detectors exhibit the desirable properties of high probability of detection and low probability of false alarm.

Mechanism of RDX-Induced Seizures in Rats

Science.gov (United States)

2009-09-01

benchmark for RDX. d. The main acute effect of RDX after ingestion of high doses is the induction of seizures accompanied by excessive salivation ...most animals that seize demonstrate excessive salivation (Schneider et al., 1977; Burdette et al., 1988; Crouse et al., 2006). These clinical signs...Padilla et al., 1998). A 2% (wet wt./vol.) homogenate was made in 0.1 M Na phosphate buffer ( pH 8.0) + 1% Triton, using a 20 sec burst (on ice) of

A case study of contaminants on military ranges: Camp Edwards, Massachusetts, USA

International Nuclear Information System (INIS)

Clausen, Jay; Robb, Joe; Curry, Diane; Korte, Nic

2004-01-01

An extensive investigation at the Camp Edwards, Massachusetts Military Reservation (MMR) demonstrates that assessment of groundwater and soil contamination at military ranges can be limited primarily to explosive-related compounds such as RDX, HMX, perchlorate, TNT and their transformation products. A modified analytical method is recommended to expand the list of explosives and to improve the detection limits. Analyses of metals, VOCs, SVOCs, and TICs are unnecessary. Soil samples may require the analyses of PAHs and PCNs for burn areas. Camp Edwards, as one of the few military ranges that have been exhaustively investigated for contaminants, is an ideal point of departure for evaluating other ranges. The permeable site soils promote leaching of contaminants and inhibit biotic and abiotic transformations. Moreover, the site has experienced an unusual extent of activities in its more than ninety years of active use. The recommendations in this report are based on data obtained for more than 200 analytes from more than 15,000 environmental samples. - Assessment of groundwater and soil contamination at US military ranges can be limited primarily to explosive-related compounds

Monodehydroascorbate reductase mediates TNT toxicity in plants.

Science.gov (United States)

Johnston, Emily J; Rylott, Elizabeth L; Beynon, Emily; Lorenz, Astrid; Chechik, Victor; Bruce, Neil C

2015-09-04

The explosive 2,4,6-trinitrotoluene (TNT) is a highly toxic and persistent environmental pollutant. Due to the scale of affected areas, one of the most cost-effective and environmentally friendly means of removing explosives pollution could be the use of plants. However, mechanisms of TNT phytotoxicity have been elusive. Here, we reveal that phytotoxicity is caused by reduction of TNT in the mitochondria, forming a nitro radical that reacts with atmospheric oxygen, generating reactive superoxide. The reaction is catalyzed by monodehydroascorbate reductase 6 (MDHAR6), with Arabidopsis deficient in MDHAR6 displaying enhanced TNT tolerance. This discovery will contribute toward the remediation of contaminated sites. Moreover, in an environment of increasing herbicide resistance, with a shortage in new herbicide classes, our findings reveal MDHAR6 as a valuable plant-specific target. Copyright © 2015, American Association for the Advancement of Science.

Verification of RDX Photolysis Mechanism

National Research Council Canada - National Science Library

Peyton, Gary

1999-01-01

... such as formaldehyde and formic acid, as well as the inorganic ions nitrate and nitrite. This implies that UV photolysis might provide a satisfactory and economical treatment system for RDX in water...

Identification and optimization of classifier genes from multi-class earthworm microarray dataset.

Directory of Open Access Journals (Sweden)

Ying Li

Full Text Available Monitoring, assessment and prediction of environmental risks that chemicals pose demand rapid and accurate diagnostic assays. A variety of toxicological effects have been associated with explosive compounds TNT and RDX. One important goal of microarray experiments is to discover novel biomarkers for toxicity evaluation. We have developed an earthworm microarray containing 15,208 unique oligo probes and have used it to profile gene expression in 248 earthworms exposed to TNT, RDX or neither. We assembled a new machine learning pipeline consisting of several well-established feature filtering/selection and classification techniques to analyze the 248-array dataset in order to construct classifier models that can separate earthworm samples into three groups: control, TNT-treated, and RDX-treated. First, a total of 869 genes differentially expressed in response to TNT or RDX exposure were identified using a univariate statistical algorithm of class comparison. Then, decision tree-based algorithms were applied to select a subset of 354 classifier genes, which were ranked by their overall weight of significance. A multiclass support vector machine (MC-SVM method and an unsupervised K-mean clustering method were applied to independently refine the classifier, producing a smaller subset of 39 and 30 classifier genes, separately, with 11 common genes being potential biomarkers. The combined 58 genes were considered the refined subset and used to build MC-SVM and clustering models with classification accuracy of 83.5% and 56.9%, respectively. This study demonstrates that the machine learning approach can be used to identify and optimize a small subset of classifier/biomarker genes from high dimensional datasets and generate classification models of acceptable precision for multiple classes.

Evaluation of the metabolic fate of munitions material (TNT & RDX) in plant systems. Initial assessment of plant DNA mutation spectra as a biomarker

Energy Technology Data Exchange (ETDEWEB)

Leung, F.; Cataldo, D.A.; Fellows, R.J.; Jarrell, A.E.; Harvey, S.D.

1995-09-01

Munitions material can enter the environment as a result of manufacturing activities and field usage. Predictor methodologies, or biomarkers would enhance evaluation of environmental impacts. The goal of this exploratory study deoxyribonucleic acid (DNA) mutation frequency as a biomarker for munitions exposure. The approach e resolution of an effective repetitive sequence probe for the identification of characteristic mutations, and (2) the development of a testing media [a clonal cell line of carrot (Daucus carota) spension cells]. Commercially available probes demonstrated marginal resolution therefore a low-C{sub o}t library was then constructed. Three colonies from the low-C{sub o}t DNA library were screened and the DNA isolates sequenced. A suspension culture of carrot (Daucus carota) was developed. A mutation spectra experiment was initiated at a 10-mg TNT/L exposure concentration with the attempt to clone over 1500 single TNT-exposed cells. Over the following six months greater than 98% of the initially isolated cells were unable to survive and produce micro calluses. The remaining calli were too few to be statistically significant and the experiment was terminated. The biomarker concept itself remains to be disproved, but the need for large numbers of uniform clones to differentiate true mutations suggest that more direct techniques using whole tissues need to be developed.

New approaches to the CL-20/HMX cocrystal a less sensitive high power explosive

OpenAIRE

Herrmannsdörfer, Dirk; Herrmann, Michael; Heintz, Thomas

2015-01-01

Understanding the kinetic and thermodynamic of the formation of the 2:1 cocrystal of CL-20 and HMX is a key factor to optimize crystallization procedures in regard to time and material efficiency as well as crystal purity. Here we describe the temperature and polymorph dependency of the solvent-mediated cocrystallization of HMX and CL-20 in 2-propanol as well as the solubility curves of CL-20 and HMX in acetone/2-propanol mixtures and acetonitrile/2-propanol mixtures at room temperature. The ...

Colorimetric-based detection of TNT explosives using functionalized silica nanoparticles.

Science.gov (United States)

Idros, Noorhayati; Ho, Man Yi; Pivnenko, Mike; Qasim, Malik M; Xu, Hua; Gu, Zhongze; Chu, Daping

2015-06-03

This proof-of-concept study proposes a novel sensing mechanism for selective and label-free detection of 2,4,6-trinitrotoluene (TNT). It is realized by surface chemistry functionalization of silica nanoparticles (NPs) with 3-aminopropyl-triethoxysilane (APTES). The primary amine anchored to the surface of the silica nanoparticles (SiO2-NH2) acts as a capturing probe for TNT target binding to form Meisenheimer amine-TNT complexes. A colorimetric change of the self-assembled (SAM) NP samples from the initial green of a SiO2-NH2 nanoparticle film towards red was observed after successful attachment of TNT, which was confirmed as a result of the increased separation between the nanoparticles. The shift in the peak wavelength of the reflected light normal to the film surface and the associated change of the peak width were measured, and a merit function taking into account their combined effect was proposed for the detection of TNT concentrations from 10-12 to 10-4 molar. The selectivity of our sensing approach is confirmed by using TNT-bound nanoparticles incubated in AptamerX, with 2,4-dinitrotoluene (DNT) and toluene used as control and baseline, respectively. Our results show the repeatable systematic color change with the TNT concentration and the possibility to develop a robust, easy-to-use, and low-cost TNT detection method for performing a sensitive, reliable, and semi-quantitative detection in a wide detection range.

Tracking the Fate of Explosive-Trinitrotriazine (RDX) in Coastal Marine Ecosystems Using Stable Isotopic Tracer

Science.gov (United States)

Ariyarathna, T. S.; Ballentine, M.; Vlahos, P.; Smith, R. W.; Bohlke, J. K.; Tobias, C. R.; Fallis, S.; Groshens, T.; Cooper, C.

2017-12-01

It has been estimated that there are hundreds of explosive-contaminated sites all over the world and managing these contaminated sites is an international challenge. As coastal zones and estuaries are commonly impacted zones, it is vital to understand the fate and transport of munition compounds in these environments. The demand for data on sorption, biodegradation and mineralization of trinitrotriazine (RDX) in coastal ecosystems is the impetus for this study using stable nitrogen isotopes to track its metabolic pathways. Mesocosm experiments representing subtidal vegetated, subtidal unvegetated and intertidal marsh ecocosms were conducted. Steady state concentrations of RDX were maintained in the systems throughout two-week time duration of experiments. Sediment, pore-water and overlying water samples were analyzed for RDX and degradation products. Isotope analysis of the bulk sediments revealed an initial rising inventory of 15N followed by a decay illustrating the role of sediments on sorption and degradation of RDX in anaerobic sediments respectively. Both pore-water and overlying water samples were analyzed for 15N inventories of different inorganic nitrogen pools including ammonium, nitrate, nitrite, nitrous oxide and nitrogen gases. RDX is mineralized to nitrogen gas through a series of intermediates leaving nitrous oxide as the prominent metabolite of RDX. Significant differences in RDX metabolism were observed in the three different ecosystems based on sediment characteristics and redox conditions in the systems. Fine grained organic carbon rich sediments show notably higher mineralization rates of RDX in terms of production of its metabolites. Quantification of degradation and transformation rates leads to mass balances of RDX in the systems. Further analysis of results provides insights for mineralization pathways of RDX into both organic and inorganic nitrogen pools entering the marine nitrogen cycle.

TNT Green Office. NESK Final Report; TNT Green Office, Hoofddorp. NESK Eindrapportage

Energy Technology Data Exchange (ETDEWEB)

Van der Spek, C; Van Rheenen, M [OVG Projectontwikkeling, Rotterdam (Netherlands)

2011-12-15

The aim of the collaboration between TNT (courier and express services) and Triodos/OVG (bank and project developer) was to realize CO2 free Green Offices in the Netherlands. The building is both developed and exploited by the same parties based on an innovative contract in which design, construction and maintenance and management are arranged. These parties are also responsible for the sustainable energy system of the building [Dutch] Doelstelling van de samenwerking tussen TNT (koerier en expresdiensten) en Triodos/OVG (bank en projectontwikkelaar) was het realiseren van CO2-emissievrije Green Offices in Nederland. Hierbij wordt het gebouw ontwikkeld en geexploiteerd door dezelfde partijen op basis van een innovatief contract waarin ontwerp, bouw, onderhoud en beheer zijn vastgelegd. Deze partijen zijn ook verantwoordelijk voor de duurzame energievoorziening van het gebouw.

Microbial and plant ecology of a long-term TNT-contaminated site

International Nuclear Information System (INIS)

Travis, Emma R.; Bruce, Neil C.; Rosser, Susan J.

2008-01-01

The contamination of the environment with explosive residues presents a serious ecological problem at sites across the world, with the highly toxic compound trinitrotoluene (TNT) the most widespread contaminant. This study examines the soil microbial community composition across a long-term TNT-contaminated site. It also investigates the extent of nitroaromatic contamination and its effect on vegetation. Concentrations of TNT and its metabolites varied across the site and this was observed to dramatically impact on the extent and diversity of the vegetation, with the most heavily contaminated area completely devoid of vegetation. Bryophytes were seen to be particularly sensitive to TNT contamination. The microbial population experienced both a reduction in culturable bacterial numbers and a shift in composition at the high concentrations of TNT. DGGE and community-level physiological profiling (CLPP) revealed a clear change in both the genetic and functional diversity of the soil when soil was contaminated with TNT. - Long-term contamination of soil with TNT reduces the extent and diversity of vegetation, decreases culturable bacterial numbers and shifts the microbial community composition

Vetiver grass is capable of removing TNT from soil in the presence of urea

Energy Technology Data Exchange (ETDEWEB)

Das, Padmini [Department of Earth and Environmental Studies, Montclair State University, One Normal Avenue, Montclair, NJ 07104 (United States); Datta, Rupali [Department of Biological Sciences, Michigan Technological University, Houghton, MI 49931 (United States); Makris, Konstantinos C., E-mail: konstantinos.makris@cut.ac.c [Cyprus International Institute for Environmental and Public Health in Association with Harvard School Of Public Health, Cyprus University of Technology, Limassol (Cyprus); Sarkar, Dibyendu [Department of Earth and Environmental Studies, Montclair State University, One Normal Avenue, Montclair, NJ 07104 (United States)

2010-05-15

The high affinity of vetiver grass for 2,4,6 trinitrotoluene (TNT) and the catalytic effectiveness of urea in enhancing plant uptake of TNT in hydroponic media we earlier demonstrated were further illustrated in this soil-pot-experiment. Complete removal of TNT in urea-treated soil was accomplished by vetiver at the low initial soil-TNT concentration (40 mg kg{sup -1}), masking the effect of urea. Doubling the initial TNT concentration (80 mg kg{sup -1}) significantly (p < 0.002) increased TNT removal by vetiver, in the presence of urea. Without vetiver grass, no significant (p = 0.475) change in the soil-TNT concentrations was observed over a period of 48 days, suggesting that natural attenuation of soil TNT could not explain the documented TNT disappearance from soil. - Vetiver grass in the presence of urea effectively removes TNT from soil.

Detection of Explosives in a Dynamic Marine Environment Using a Moored TNT Immunosensor

Directory of Open Access Journals (Sweden)

Paul T. Charles

2014-02-01

Full Text Available A field demonstration and longevity assessment for long-term monitoring of the explosive 2,4,6-trinitrotoluene (TNT in a marine environment using an anti-TNT microfluidic immunosensor is described. The TNT immunosensor is comprised of a microfluidic device with 39 parallel microchannels (2.5 cm × 250 µm × 500 µm, L × W × D fabricated in poly(methylmethacrylate (PMMA, then chemically functionalized with antibodies possessing a high affinity for TNT. Synthesized fluorescence reporter complexes used in a displacement-based assay format were used for TNT identification. For field deployment the TNT immunosensor was configured onto a submersible moored steel frame along with frame controller, pumps and TNT plume generator and deployed pier side for intermittent plume sampling of TNT (1h increments. Under varying current and tidal conditions trace levels of TNT in natural seawater were detected over an extended period (>18 h. Overnight operation and data recording was monitored via a web interface.

Microbial Degradation of RDX and HMX

Science.gov (United States)

2004-02-01

cultivated in the M-succinate medium as previously described (Coleman et al., 1998). P. chrysosporium ATCC 24725 was provided by Ian Reid (Paprican...Sunahara. 1999. Ecotoxicological Evaluation of a Bench–Scale Bioslurry Treating Explosives – Spiked Soil. Bioremediation J. 3(3), 233-245. 217...1999. Ecotoxicological characterization of energetic substances using a soil extraction procedure. Ecotoxicol. Environ. Safety 43, 138-148

New Approaches to Evaluate the Biological Degradation of RDX in Groundwater

Science.gov (United States)

2014-08-27

again indicate the diversity of active microorganisms associated with RDX biodegradation in the environmental samples. When cheese whey was absent...34  2.2 Task 2 – Geochemical and Environmental Conditions Affecting RDX Biodegradation ............ 36  2.2.1 Objective...Degrading Microorganisms . 49  2.3.1 Objective

Linear flow dynamics near a T/NT interface

Science.gov (United States)

Teixeira, Miguel; Silva, Carlos

2011-11-01

The characteristics of a suddenly-inserted T/NT interface separating a homogeneous and isotropic shear-free turbulence region from a non-turbulent flow region are investigated using rapid distortion theory (RDT), taking full account of viscous effects. Profiles of the velocity variances, TKE, viscous dissipation rate, turbulence length scales, and pressure statistics are derived, showing very good agreement with DNS. The normalized inviscid flow statistics at the T/NT interface do not depend on the form of the assumed TKE spectrum. In the non-turbulent region, where the flow is irrotational (except within a thin viscous boundary layer), the dissipation rate decays as z-6, where z is distance from the T/NT interface. The mean pressure exhibits a decrease towards the turbulence due to the associated velocity fluctuations, consistent with the generation of a mean entrainment velocity. The vorticity variance and dissipation rate display large maxima at the T/NT interface due to the existing inviscid discontinuities of the tangential velocity, and these maxima are quantitatively related to the thickness of the viscous boundary layer (VBL). At equilibrium, RDT suggests that the thickness of the T/NT interface scales on the Kolmogorov microscale. We acknowledge the financial support of FCT under Project PTDC/EME-MFE/099636/2008.

Identification of Metabolic Routes and Catabolic Enzymes Involved in Phytoremediation of the Nitro-Substituted Explosives TNT, RDX, and HMX

Science.gov (United States)

2006-07-31

from various well-studied spermatophyte plants species (e.g., A. thaliana, Zea mays, Oryza sativa). The two P. trichocarpa housekeeping genes used as...Nitrate oxidoreductase from Aspergillus niger. Environ. Sci. Technol. 36, 3104-3108. Bhushan, B., Trott, S., Spain, J. C., Halasz, A., Pacquet, L

Analysis of compaction shock interactions during DDT of low density HMX

Science.gov (United States)

Rao, Pratap T.; Gonthier, Keith A.

2017-01-01

Deflagration-to-Detonation Transition (DDT) in confined, low density granular HMX occurs by a complex mechanism that involves compaction shock interactions within the material. Piston driven DDT experiments indicate that detonation is abruptly triggered by the interaction of a strong combustion-supported secondary shock and a piston-supported primary (input) shock, where the nature of the interaction depends on initial packing density and primary shock strength. These interactions influence transition by affecting dissipative heating within the microstructure during pore collapse. Inert meso-scale simulations of successive shock loading of low density HMX are performed to examine how dissipation and hot-spot formation are affected by the initial density, and the primary and secondary shock strengths. This information is used to formulate an ignition and burn model for low density HMX that accounts for the effect of shock densensitization on burn. Preliminary DDT predictions are presented that illustrate how primary shock strength affects the transition mechanism.

Biodegradation of RDX within soil-water slurries using a combination of differing redox incubation conditions

International Nuclear Information System (INIS)

Waisner, S.; Hansen, L.; Fredrickson, H.; Nestler, C.; Zappi, M.; Banerji, S.; Bajpai, R.

2002-01-01

Biodegradation of 14 C-tagged hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was studied in aerobic, anaerobic, and anaerobic/aerobic slurries to identify the conditions maximizing RDX-mineralization in Cornhusker Army Ammunition Plant (CAAP, NE) groundwater. Supplementation with phosphate and adequate quantities of acetate caused 25% mineralization of RDX in 3 weeks by microorganisms native to CAAP. Under anaerobic conditions, the same supplementation resulted in 20% mineralization in 3 weeks and 30% mineralization in 6 weeks. The highest degree of mineralization (50%) was obtained under aerobic conditions when the contaminated groundwater was augmented with a consortium of three microbes isolated from another RDX contaminated soil (Hastings, NE) in addition to supplemented with phosphate and acetic acid. Use of complex organic sources (potato or corn starch) slowed down the rates of mineralization under anaerobic conditions, but rapid mineralization ensued as soon as the aerobic conditions were created. Final RDX concentrations in aqueous phase were below detection limit under most conditions. Assimilation of RDX by the cells was negligible

Theoretical insight into the solvent effect of H2O and formamide on the cooperativity effect in HMX complex.

Science.gov (United States)

Meng, Rui-Hong; Cao, Xiong; Hu, Shuang-Qi; Hu, Li-Shuang

2017-08-01

The cooperativity effects of the H-bonding interactions in HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane)∙∙∙HMX∙∙∙FA (formamide), HMX∙∙∙HMX∙∙∙H 2 O and HMX∙∙∙HMX∙∙∙HMX complexes involving the chair and chair-chair HMX are investigated by using the ONIOM2 (CAM-B3LYP/6-31++G(d,p):PM3) and ONIOM2 (M06-2X/6-31++G(d,p):PM3) methods. The solvent effect of FA or H 2 O on the cooperativity effect in HMX∙∙∙HMX∙∙∙HMX are evaluated by the integral equation formalism polarized continuum model. The results show that the cooperativity and anti-cooperativity effects are not notable in all the systems. Although the effect of solvation on the binding energy of ternary system HMX∙∙∙HMX∙∙∙HMX is not large, that on the cooperativity of H-bonds is notable, which leads to the mutually strengthened H-bonding interaction in solution. This is perhaps the reason for the formation of different conformation of HMX in different solvent. Surface electrostatic potential and reduced density gradient are used to reveal the nature of the solvent effect on cooperativity effect in HMX∙∙∙HMX∙∙∙HMX. Graphical abstract RDG isosurface and electrostatic potential surface of HMX∙∙∙HMX∙∙∙HMX.

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) degradation by Acetobacterium paludosum.

Science.gov (United States)

Sherburne, Leslie A; Shrout, Joshua D; Alvarez, Pedro J J

2005-12-01

Substrates and nutrients are often added to contaminated soil or groundwater to enhance bioremediation. Nevertheless, this practice may be counterproductive in some cases where nutrient addition might relieve selective pressure for pollutant biodegradation. Batch experiments with a homoacetogenic pure culture of Acetobacterium paludosum showed that anaerobic RDX degradation is the fastest when auxiliary growth substrates (yeast extract plus fructose) and nitrogen sources (ammonium) are not added. This bacterium degraded RDX faster under autotrophic (H2-fed) than under heterotrophic conditions, even though heterotrophic growth was faster. The inhibitory effect of ammonium is postulated to be due to the repression of enzymes that initiate RDX degradation by reducing its nitro groups, based on the known fact that ammonia represses nitrate and nitrite reductases. This observation suggests that the absence of easily assimilated nitrogen sources, such as ammonium, enhances RDX degradation. Although specific end products of RDX degradation were not determined, the production of nitrous oxide (N2O) suggests that A. paludosum cleaved the triazine ring.

Comparative study of the vapor analytes of trinitrotoluene (TNT)

Science.gov (United States)

Edge, Cindy C.; Gibb, Julie; Dugan, Regina E.

1998-12-01

Trinitrotoluene (TNT) is a high explosive used in most antipersonnel and antitank landmines. The Institute for Biological Detection Systems (IBDS) has developed a quantitative vapor delivery system, termed olfactometer, for conducting canine olfactory research. The research is conducted utilizing dynamic conditions, therefore, it is imperative to evaluate the headspace of TNT to ensure consistency with the dynamic generation of vapor. This study quantified the vapor headspace of military- grade TNT utilizing two different vapor generated methodologies, static and dynamic, reflecting differences between field and laboratory environments. Static vapor collection, which closely mimics conditions found during field detection, is defined as vapor collected in an open-air environment at ambient temperature. Dynamic vapor collection incorporates trapping of gases from a high flow vapor generation cell used during olfactometer operation. Analysis of samples collected by the two methodologies was performed by gas chromatography/mass spectrometry and the results provided information with regard to the constituents detected. However, constituent concentration did vary between the sampling methods. This study provides essential information regarding the vapor constituents associated with the TNT sampled using different sampling methods. These differences may be important in determining the detection signature dogs use to recognize TNT.

Forensic analysis of high explosives residues in post-blast water samples employing solid phase extraction for analyte pro-concentration

International Nuclear Information System (INIS)

Umi Kalsom Ahmad; Rajendran, Sumathy; Ling, Lee Woan

2008-01-01

Nitro aromatic, nitramine and nitrate ester compounds are a major group of high order explosive or better known as military explosives. Octahydro-1,3,5,7-tetrazocine (HMX), 1,3,5-hexahydro-1,3,5-trinitro triazine (RDX), 2,4,6-trinitro-toluene (TNT), pentaerythritol tetranitrate (PETN) and 2,4-dinitrotoluene (2,4-DNT) are secondary high explosives classified as most commonly used explosives components. There is an increasing demand for pre-concentration of these compounds in water samples as the sensitivity achieved by instrumental analytical methods for these high explosives residues are the main drawback in the application at trace levels for forensic analysis. Hence, a simple cartridge solid phase extraction (SPE) procedure was optimized as the off-line extraction and pre-concentration method to enhance the detection limit of high explosive residues using micellar electrokinetic chromatography (MEKC) and gas chromatography with electron-capture detection (GC-ECD) methods. The SPE cartridges utilized LiChrolut EN as the SPE adsorbent. By emplying pre-concentration using SPE, the detection limits of the target analytes in water sample were lowered by more than 1000 times with good percentage recovery (>87%) for MEKC method and lowered by 120 times with more than 2 % percentage recovery for GC-ECD methods. In order to test the feasibility of the developed method to real cases, post-blast water samples were analyzed. The post-blast water samples which were collected from Baling Bom training range, Ulu Kinta, Perak contained RDX and PETN in the range of 0.05 - 0.17 ppm and 0.0124 - 0.0390 ppm respectively. (author)

Molecular imprinting at walls of silica nanotubes for TNT recognition.

Science.gov (United States)

Xie, Chenggen; Liu, Bianhua; Wang, Zhenyang; Gao, Daming; Guan, Guijian; Zhang, Zhongping

2008-01-15

This paper reports the molecular imprinting at the walls of highly uniform silica nanotubes for the recognition of 2,4,6-trinitrotoluene (TNT). It has been demonstrated that TNT templates were efficiently imprinted into the matrix of silica through the strong acid-base pairing interaction between TNT and 3-aminopropyltriethoxysilane (APTS). TNT-imprinted silica nanotubes were synthesized by the gelation reaction between APTS and tetraethylorthosilicate (TEOS), selectively occurring at the porous walls of APTS-modified alumina membranes. The removal of the original TNT templates leaves the imprinted cavities with covalently anchored amine groups at the cavity walls. A high density of recognition sites with molecular selectivity to the TNT analyte was created at the wall of silica nanotubes. Furthermore, most of these recognition sites are situated at the inside and outside surfaces of tubular walls and in the proximity of the two surfaces due to the ultrathin wall thickness of only 15 nm, providing a better site accessibility and lower mass-transfer resistance. Therefore, greater capacity and faster kinetics of uptaking target species were achieved. The silica nanotube reported herein is an ideal form of material for imprinting various organic or biological molecules toward applications in chemical/biological sensors and bioassay.

Sequence and 3D structure based analysis of TNT degrading proteins in Arabidopsis thaliana.

Science.gov (United States)

Bhattacherjee, Amrita; Mandal, Rahul Shubhra; Das, Santasabuj; Kundu, Sudip

2014-03-01

TNT, accidentally released at several manufacturing sites, contaminates ground water and soil. It has a toxic effect to algae and invertebrate, and chronic exposure to TNT also causes harmful effects to human. On the other hand, many plants including Arabidopsis thaliana have the ability to metabolize TNT either completely or at least to a reduced less toxic form. In A. thaliana, the enzyme UDP glucosyltransferase (UDPGT) can further conjugate the reduced forms 2-HADNT and 4-HADNT (2-hydroxylamino-4, 6- dinitrotoluene and 4-hydroxylamino-2, 6- dinitrotoluene) of TNT. Based on the experimental analysis, existing literature and phylogenetic analysis, it is evident that among 107 UDPGT proteins only six are involved in the TNT degrading process. A total of 13 UDPGT proteins including five of these TNT degrading proteins fall within the same group of phylogeny. Thus, these 13 UDPGT proteins have been classified into two groups, TNT-degrading and TNT-non-degrading proteins. To understand the differences in TNT-degrading capacities; using homology modeling we first predicted two structures, taking one representative sequence from both the groups. Next, we performed molecular docking of the modeled structure and TNT reduced form 2-hydroxylamino-4, 6- dinitrotoluene (2-HADNT). We observed that while the Trp residue located within the active site region of the TNT- degrading protein showed π-Cation interaction; such type of interaction was absent in TNT-non-degrading protein, as the respective Trp residue lay outside of the pocket in this case. We observed the conservation of this π-Cation interaction during MD simulation of TNT-degrading protein. Thus, the position and the orientation of the active site residue Trp could explain the presence and absence of TNT-degrading capacity of the UDPGT proteins.

Theoretical studies on the thermodynamic properties and detonation properties of cyclotrimethylene trinitramine (RDX with aluminum and boron metals.

Directory of Open Access Journals (Sweden)

Nilgün Şen

2016-10-01

Full Text Available The B3LYP/6-311++G(2df,2p density functional theory (DFT method was used to investigate molecular geometry and thermodynamic properties of RDX and RDX derivatives containing Al and B metals. The detonation velocity (D and detonation pressure (P, estimated by using Kamlet–Jacobs and in literature equations, respectively. Total energies (Et, frontier orbital energy (EHOMO, ELOMO, energy gap (ΔELUMO–HOMO and theoretical molecular density (ρ were calculated with Spartan 14 software package program. It was shown that the presence of aluminum and boron atoms affects the good thermal stabilities. The results show that the composite RDX-Al, RDX-B derivatives have higher detonation performance and higher density than RDX. RDX-Al derivatives appeared to be superior to RDX-B mixtures in terms of these parameters. These results provide information on the moleculer design of new energetic materials.

Toxicity of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) in three vertebrate species.

Science.gov (United States)

Johnson, Mark S; McFarland, Craig A; Bazar, Matthew A; Quinn, Michael J; LaFiandra, Emily May; Talent, Larry G

2010-04-01

The explosive, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine or high-melting explosive (HMX), has been found in soils in areas used for testing and training by the military. Many of these areas contain habitat for valued wildlife species. In an effort to better understand the environmental consequences from exposure, a reptilian (western fence lizard [Sceloporus occidentalis]), an amphibian (red-backed salamander [Plethodon cinereus]), and a mammalian species (rabbit [Oryctolagus cuniculus]) were exposed to HMX under controlled laboratory conditions. Lizards and rabbits were exposed to HMX by way of corn oil through gavage, and salamanders were exposed to HMX in soil. Two deaths occurred from acute oral exposures to lizards to 5000 mg HMX/kg BW. Histological and gross pathologic assessment suggested gut impaction as a possible cause of death. Salamanders exposed to concentrations of HMX in soil 24 h after oral exposures. An LD(50) for rabbits was calculated as 93 mg/kg (95% confidence interval 76-117). A subacute 14-day testing regime found a lowest observed effect level of 10 mg/kg-d and a no observed adverse effect level of 5 mg/kg-d based on hyperkinesia and seizure incidence, although changes suggesting functional hepatic alterations were also found. These data suggest that physiologic differences between species, particularly in gastrointestinal structure and function, can affect the absorption of HMX and hence lead to marked differences in toxicity from exposure to the same compound.

Multi-colorimetric sensor array for detection of explosives in gas and liquid phase

DEFF Research Database (Denmark)

Kostesha, Natalie; Alstrøm, Tommy Sonne; Johnsen, C.

2011-01-01

In the framework of the research project "Xsense" at the Technical University of Denmark (DTU) we are developing a simple colorimetric sensor array which can be useful in detection of explosives like DNT, TATP, HMX, RDX and identification of reagents needed for making homemade explosives. The tec......In the framework of the research project "Xsense" at the Technical University of Denmark (DTU) we are developing a simple colorimetric sensor array which can be useful in detection of explosives like DNT, TATP, HMX, RDX and identification of reagents needed for making homemade explosives...... to the analytes creates a color difference map which gives a unique fingerprint for each explosive and VOCs. Such sensing technology can be used for screening relevant explosives in a complex background as well as to distinguish mixtures of volatile organic compounds distributed in gas and liquid phases....... This sensor array is inexpensive, and can potentially be produced as single use disposable....

Experimental Studies on Improved Plastic Bonded Explosives Materials (PBXs for Controlled Fragmentation Warheads

Directory of Open Access Journals (Sweden)

Elsharkawy Karim

2017-01-01

Full Text Available This paper describes formulations of plastic bonded explosives (PBXs based on three highly brisant explosives, namely 1,3,5-trinitro-1,3,5-triazinane (RDX, 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX and pentaerythritoltetranitrate (PETN with polyurethane (PU based on Glycidyl azide polymer (GAP as an energetic binder in comparison with composition-B, which used in the fragmentation warheads. The sensitivity and performance properties of different types of PBXs were evaluated by experimental results of prepared selected PBX compositions. Casting technique was used to prepare the selected compositions containing 14% PU based on GAP. It has been observed that the brisance of the PBX based on HMX was higher than that of comp-B by 21.3 %, the detonation velocity showed a remarkable increase of the order of 8480 (m/s while that of comp-B was 7638 (m/s. A controlled fragmentation warhead with an outer grooving warhead case of dimensions 100x35x4 mm was used and arena test was carried out to determine the lethal zone of the fragmentation warhead. The lethal zone obtained from arena test for PBX composition based on HMX named PBXHG4 was higher than that based on RDX or PETN, and than that of comp-B by 40%.

Validation of Passive Sampling Devices for Monitoring of Munitions Constituents in Underwater Environments

Science.gov (United States)

2017-09-01

TNT TOC TSS Low Order Detonation Munitions constituents Munitions Debris Method Detection Limit Munitions and explosives of concern Mean low...Total organic carbon ( TOC ) and grain size distribution from stations A1, T10, T11, and T12 at BSS...16 syringes/stn) TNT, ADNTs, DNTs, RDX 4 locations in BSS based on positive POCIS results Sediment 5 TOC , grain size 4, co-located with sediment

A review of Explosives Used in Explosive Excavation Research Laboratory Projects Since 1969

Science.gov (United States)

1974-12-01

Boron compounds Potassium dichramat« Antimony compounds Bismuth compounds P«riodat«s Litharge Guar gum (polysaccSarid«) Storch Acrylomid... gum , and gelled with a cross- linking agent. The i-arliest slurries used Government surplus TNT as a fuel-sensitizer, but the majority o...Nonexplosive TNT PETN RDX Rentalite Composition B Guanidine nitrate Smokeless powder Nitres*: ch Alky’amine nitrates Nit.omannite Aluminum Sugar

Nanoindentation of HMX and Idoxuridine to Determine Mechanical Similarity

Directory of Open Access Journals (Sweden)

Alexandra C. Burch

2017-11-01

Full Text Available Assessing the mechanical behavior (elastic properties, plastic properties, and fracture phenomena of molecular crystals is often complicated by the difficulty in preparing samples. Pharmaceuticals and energetic materials in particular are often used in composite structures or tablets, where the individual grains can strongly impact the solid behavior. Nanoindentation is a convenient method to experimentally assess these properties, and it is used here to demonstrate the similarity in the mechanical properties of two distinct systems: individual crystals of the explosive cyclotetramethylene tetranitramine (HMX and the pharmaceutical idoxuridine were tested in their as-precipitated state, and the effective average modulus and hardness (which can be orientation dependent were determined. Both exhibit a hardness of 1.0 GPa, with an effective reduced modulus of 25 and 23 GPa for the HMX and idoxuridine, respectively. They also exhibit similar yield point behavior. This indicates idoxuridine may be a suitable mechanical surrogate (or “mock” for HMX. While the methodology to assess elastic and plastic properties was relatively insensitive to specific crystal orientation (i.e., a uniform distribution in properties was observed for all random crystals tested, the indentation-induced fracture properties appear to be much more sensitive to tip-crystal orientation, and an unloading slope analysis is used to demonstrate the need for further refinement in relating toughness to orientation in these materials with relatively complex slip systems and crystal structures.

Stable isotope probing reveals the importance of Comamonas and Pseudomonadaceae in RDX degradation in samples from a Navy detonation site.

Science.gov (United States)

Jayamani, Indumathy; Cupples, Alison M

2015-07-01

This study investigated the microorganisms involved in hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) degradation from a detonation area at a Navy base. Using Illumina sequencing, microbial communities were compared between the initial sample, samples following RDX degradation, and controls not amended with RDX to determine which phylotypes increased in abundance following RDX degradation. The effect of glucose on these communities was also examined. In addition, stable isotope probing (SIP) using labeled ((13)C3, (15)N3-ring) RDX was performed. Illumina sequencing revealed that several phylotypes were more abundant following RDX degradation compared to the initial soil and the no-RDX controls. For the glucose-amended samples, this trend was strong for an unclassified Pseudomonadaceae phylotype and for Comamonas. Without glucose, Acinetobacter exhibited the greatest increase following RDX degradation compared to the initial soil and no-RDX controls. Rhodococcus, a known RDX degrader, also increased in abundance following RDX degradation. For the SIP study, unclassified Pseudomonadaceae was the most abundant phylotype in the heavy fractions in both the presence and absence of glucose. In the glucose-amended heavy fractions, the 16S ribosomal RNA (rRNA) genes of Comamonas and Anaeromxyobacter were also present. Without glucose, the heavy fractions also contained the 16S rRNA genes of Azohydromonas and Rhodococcus. However, all four phylotypes were present at a much lower level compared to unclassified Pseudomonadaceae. Overall, these data indicate that unclassified Pseudomonadaceae was primarily responsible for label uptake in both treatments. This study indicates, for the first time, the importance of Comamonas for RDX removal.

Separation and determination of PETN and TNT by HPTLC

Energy Technology Data Exchange (ETDEWEB)

Chaloosi, Marzieh; Nejad-Darzi, Seyed Karim Hassani; Ghoulipour, Vanik [Faculty of Chemistry, University of Tarbiat Moallem, Tehran (Iran)

2009-02-15

High-performance thin layer chromatography (HPTLC) has been used for the separation and quantification of 2,4,6-trinitrotoluene (TNT) and pentaerythritol tetranitrate (PETN). The compounds were separated on silica gel 60 F{sub 254} with a double development system of trichloroethylene-acetone 4:1 and petroleum ether-acetone 5.7:1. For obtaining chromatograms of these materials, UV detection was performed at 215 and 250 nm for PETN and TNT, respectively. The linear dynamic range was 0.835-83.50 {mu}g per spot for PETN and 0.045-1.44 {mu}g per spot for TNT. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

Performance of mesophilic anaerobic granules for removal of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) from aqueous solution

International Nuclear Information System (INIS)

An Chunjiang; He Yanling; Huang Guohe; Liu Yonghong

2010-01-01

The performance of mesophilic anaerobic granules to degrade octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) was investigated under various conditions. The results of batch experiments showed that anaerobic granules were capable of removing HMX from aqueous solution with high efficiency. Both biotic and abiotic mechanisms contributed to the removal of HMX by anaerobic granules under mesophilic conditions. Adsorption appeared to play a significant role in the abiotic process. Furthermore, HMX could be biodegraded by anaerobic granules as the sole substrate. After 16 days of incubation, 99.04% and 96.42% of total HMX could be removed by 1 g VSS/L acclimated and unacclimated granules, respectively. Vancomycin, an inhibitor of acetogenic bacteria, caused a significant inhibition of HMX biotransformation, while 2-bromoethanesulfonic acid, an inhibitor of methanogenic bacteria, only resulted in a slight decrease of metabolic activity. The presence of the glucose, as a suitable electron donor and carbon source, was found to enhance the degradation of HMX by anaerobic granules. Our study showed that sulfate had little adverse effects on biotransformation of HMX by anaerobic granules. However, nitrate had significant inhibitory effect on the extent of HMX removal especially in the initial period. This study offered good prospects of using high-rate anaerobic technology in the treatment of munition wastewater.

Water quality criteria for hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)

Energy Technology Data Exchange (ETDEWEB)

Etnier, E.L.

1989-04-01

The occurrence of the munitions compound hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in groundwater surrounding Army ammunition plants may result in contamination of local drinking water supplies. RDX exerts its primary toxic effect in humans on the central nervous system, but also involves gastrointestinal and renal effects. Symptomatic effects following acute exposure include hyperirritability, nausea, vomiting, generalized epileptiform seizures, and prolonged postictal confusion and amnesia. Health effects data were analyzed for RDX, and although no controlled human studies exist concerning the acute or chronic toxic effects of exposure to RDX, sufficient animal toxicity data are available to derive an ambient water quality criterion for the protection of human health. This paper summarizes the available literature on metabolism of RDX and human and animal toxicity. Based on noncarcinogenic mammalian toxicity data, and following the methodologies of the U.S. Environmental Protection Agency, an ambient water quality criterion for the protection of human health of 103 micrograms/liter is proposed for ingestion of drinking water and aquatic foodstuffs. A criterion of 105 micrograms/liter is proposed for ingestion of drinking water alone.54 references.

Effects of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in zebrafish: General and reproductive toxicity

Science.gov (United States)

Mukhi, S.; Patino, R.

2008-01-01

Mixed-sex populations of young adult zebrafish (???2-month-old) were exposed to measured RDX concentrations of 0, 1 or 9.6 ppm for up to 12 weeks followed by a 15-day rearing period in untreated water. RDX caused high mortality at 9.6 ppm, with most deaths occurring within the first 8 weeks of exposure. RDX at 9.6 ppm caused lower body weights at 4 and 8 weeks of exposure; and at 1 ppm, lower body weight was observed only at 4 weeks. Fish length was not affected by treatment at any time during the exposure period. The bioconcentration factor for RDX seemed to be influenced by time of exposure but not by water RDX concentration; its overall values were 1.01 ?? 0.13, 0.91 ?? 0.06 and 2.23 ?? 0.04 at 4, 8 weeks and 12 weeks, respectively. RDX was not detected in fish collected after the 15-day recovery period. In a separate experiment, adult females and males were separately exposed to RDX at measured concentrations of 0, 0.5 and 3.2 ppm for a period of 6 weeks. Reproductive performance was evaluated by biweekly breeding of the fish and measuring packed-egg volume (PEV) as index of fecundity. At 0.5 ppm, RDX caused elevated PEV levels relative to the control value at 2 weeks but not at 4 or 6 weeks, whereas no significant effects were noted at 3.2 ppm. Egg fertilization and embryo hatching rates were not affected by RDX at any of the concentrations tested. In conclusion, RDX at sublethal concentrations causes short-term negative effects on growth and, at 0.5 ppm, positive effects on fecundity. ?? 2008 Elsevier Ltd.

Feasibility of In Situ Redox Manipulation of Subsurface Sediments for RDX Remediation at Pantex

Energy Technology Data Exchange (ETDEWEB)

Szecsody, James E.; Fruchter, Jonathan S.; Mckinley, Mark A.; Resch, Charles T.; Gilmore, Tyler J.

2001-12-31

This laboratory study was conducted to assess RDX (hexahydro-1,3,5-trinitro-1,3,5 triazine) abiotic degradation by chemically reduced sediments and other geochemical aspects of the application of this technology to remediation of RDX contamination in groundwater at the U.S. DOE Pantex facility...

TNT removal from culture media by three commonly available wild plants growing in the Caribbean.

Science.gov (United States)

Correa-Torres, Sandra N; Pacheco-Londoño, Leonardo C; Espinosa-Fuentes, Eduardo A; Rodríguez, Lolita; Souto-Bachiller, Fernando A; Hernández-Rivera, Samuel P

2012-01-01

Plants growing in the Caribbean, Rubia tinctorum, Lippia dulcis and Spermacoce remota, were used in vitro to remove TNT from culture media. Plants were found to be resistant to high TNT levels. S. remota was able to remove TNT in less than 48 h. Part of the TNT was physically removed from the culture media by evaporation.

High-Pressure Behaviour of β-HMX Crystal Studied by DFT-LDA

International Nuclear Information System (INIS)

Dan, Lian; Lai-Yu, Lu; Dong-Qing, Wei; Qing-Ming, Zhang; Zi-Zheng, Gong; Yong-Xin, Guo

2008-01-01

Density functional theory (DFT) with local density approximation (LDA) is employed to study the structural and electronic properties of the high explosive octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) under high pressure compression up to 40 GPa. Pressure dependences of the cell volume, lattice constants, and molecular geometry of solid β-HMX are presented and discussed. It is found that N-N and N-C bonds are subject to significant change. This may implies that these bonds may be related to the sensitivity. The band gap is calculated and plotted as a function of pressure. Compared the experimental results with other theoretical works we find that LDA gives good results

Pressure Dependent Decomposition Kinetics of the Energetic Material HMX up to 3.6 GPa

Energy Technology Data Exchange (ETDEWEB)

Glascoe, E A; Zaug, J M; Burnham, A K

2009-05-29

The effect of pressure on the thermal decomposition rate of the energetic material HMX was studied. HMX was precompressed in a diamond anvil cell (DAC) and heated at various rates. The parent species population was monitored as a function of time and temperature using Fourier transform infrared (FTIR) spectroscopy. Decomposition rates were determined by fitting the fraction reacted to the extended-Prout-Tompkins nucleation-growth model and the Friedman isoconversional method. The results of these experiments and analysis indicate that pressure accelerates the decomposition at low to moderate pressures (i.e. between ambient pressure and 1 GPa) and decelerates the decomposition at higher pressures. The decomposition acceleration is attributed to pressure enhanced autocatalysis whereas the deceleration at high pressures is attributed pressure inhibiting bond homolysis step(s), which would result in an increase in volume. These results indicate that both {beta} and {delta} phase HMX are sensitive to pressure in the thermally induced decomposition kinetics.

Integrated Data Collection Analysis (IDCA) Program - RDX Standard Data Set 2

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorensen, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Phillips, Jason J. [Air Force Research Lab. (AFRL), Tyndall Air Force Base, FL (United States); Shelley, Timothy J. [Applied Research Associates, Tyndall Air Force Base, FL (United States); Reyes, Jose A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2013-02-20

The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small- Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of the RDX Type II Class 5 standard, from testing the second time in the Proficiency Test. This RDX testing (Set 2) compared to the first (Set 1) was found to have about the same impact sensitivity, have more BAM friction sensitivity, less ABL friction sensitivity, similar ESD sensitivity, and same DSC sensitivity.

Deletion of a conserved regulatory element required for Hmx1 expression in craniofacial mesenchyme in the dumbo rat: a newly identified cause of congenital ear malformation

Directory of Open Access Journals (Sweden)

Lely A. Quina

2012-11-01

Hmx1 is a homeodomain transcription factor expressed in the developing eye, peripheral ganglia, and branchial arches of avian and mammalian embryos. Recent studies have identified a loss-of-function allele at the HMX1 locus as the causative mutation in the oculo-auricular syndrome (OAS in humans, characterized by ear and eye malformations. The mouse dumbo (dmbo mutation, with similar effects on ear and eye development, also results from a loss-of-function mutation in the Hmx1 gene. A recessive dmbo mutation causing ear malformation in rats has been mapped to the chromosomal region containing the Hmx1 gene, but the nature of the causative allele is unknown. Here we show that dumbo rats and mice exhibit similar neonatal ear and eye phenotypes. In midgestation embryos, dumbo rats show a specific loss of Hmx1 expression in neural-crest-derived craniofacial mesenchyme (CM, whereas Hmx1 is expressed normally in retinal progenitors, sensory ganglia and in CM, which is derived from mesoderm. High-throughput resequencing of 1 Mb of rat chromosome 14 from dmbo/dmbo rats, encompassing the Hmx1 locus, reveals numerous divergences from the rat genomic reference sequence, but no coding changes in Hmx1. Fine genetic mapping narrows the dmbo critical region to an interval of ∼410 kb immediately downstream of the Hmx1 transcription unit. Further sequence analysis of this region reveals a 5777-bp deletion located ∼80 kb downstream in dmbo/dmbo rats that is not apparent in 137 other rat strains. The dmbo deletion region contains a highly conserved domain of ∼500 bp, which is a candidate distal enhancer and which exhibits a similar relationship to Hmx genes in all vertebrate species for which data are available. We conclude that the rat dumbo phenotype is likely to result from loss of function of an ultraconserved enhancer specifically regulating Hmx1 expression in neural-crest-derived CM. Dysregulation of Hmx1 expression is thus a candidate mechanism for congenital ear

Yield Stress Model for Molten Composition B-3

Science.gov (United States)

Davis, Stephen; Zerkle, David

2017-06-01

Composition B-3 (Comp B-3) is a melt-castable explosive composed of 60/40 wt% RDX/TNT (hexahydro-1,3,5-trinitro-1,3,5-triazine/2,4,6-trinitrotoluene). During casting operations thermal conditions are controlled which along with the low melting point of TNT and the insensitivity of the mixture to external stimuli leading to safe use. Outside these standard operating conditions a more rigorous model of Comp B-3 rheological properties is necessary to model thermal transport as Comp B-3 evolves from quiescent solid through vaporization/decomposition upon heating. One particular rheological phenomena of interest is Bingham plasticity, where a material behaves as a quiescent solid unless a sufficient load is applied, resulting in fluid flow. In this study falling ball viscometer data is used to model the change in Bingham plastic yield stresses as a function of RDX particle volume fraction; a function of temperature. Results show the yield stress of Comp B-3 (τy) follows the expression τy = B ϕ -ϕc N , where Φ and Φc are the volume fraction of RDX and a critical volume fraction, respectively and B and N are experimentally evaluated constants.

Compaction of granular HMX: P-α porosity model in CTH hydrocode

Directory of Open Access Journals (Sweden)

K. S. Mahon

2015-12-01

Full Text Available Compaction waves traveling through porous cyclotetramethylene-tetranitramine (HMX are computationally modeled using the Eulerian hydrocode CTH and validated with gas gun experimental data. The method employed use of a newly generated set of P-α parameters for granular HMX in a Mie-Gruneisen equation of state. The P-α model adds a separate parameter to differentiate between the volume changes of a solid material due to compression from the volume change due to compaction, void collapse in a granular material. Computational results are compared via five validation schema for two different initial-porosity experiments. These schema include stress measurements, velocity rise times and arrival times, elastic sound speeds though the material and final compaction densities for a series of two different percent Theoretical Maximum Density (TMD HMX sets of experimental data. There is a good agreement between the simulations and the experimental gas gun data with the largest source of error being an 11% overestimate of the peak stress which may be due to impedance mismatch on the experimental gauge interface. Determination of these P-α parameters are important as they enable modeling of porosity and are a vital first step in modeling of precursory hotspots, caused by hydrodynamic collapse of void regions or grain interactions, prior to deflagration to detonation transition of granular explosives.

Uptake and effects of 2, 4, 6 - trinitrotoluene (TNT) in juvenile Atlantic salmon (Salmo salar).

Science.gov (United States)

Mariussen, Espen; Stornes, Siv Marie; Bøifot, Kari Oline; Rosseland, Bjørn Olav; Salbu, Brit; Heier, Lene Sørlie

2018-01-01

Organ specific uptake and depuration, and biological effects in Atlantic salmon (Salmo salar) exposed to 2, 4, 6-trinitrotoluene (TNT) were studied. Two experiments were conducted, the first using radiolabeled TNT ( 14 C-TNT, 0.16mg/L) to study uptake (48h) and depuration (48h), while the second experiment focused on physiological effects in fish exposed to increasing concentrations of unlabeled TNT (1μg-1mg/L) for 48h. The uptake of 14 C-TNT in the gills and most of the organs increased rapidly during the first 6h of exposure (12h in the brain) followed by a rapid decrease even though the fish were still exposed to TNT in the water. The radioactivity in the gall bladder reached a maximum after 55h, 7h after the transfer to the clean water. A high concentration of 14 C-TNT in the gall bladder indicates that TNT is excreted through the gall bladder. Mortality (2 out of 14) was observed at a concentration of 1mg/L, and the surviving fish had hemorrhages in the dorsal muscle tissue near the spine. Analysis of the physiological parameters in blood from the high exposure group revealed severe effects, with an increase in the levels of glucose, urea and HCO 3 , and a decrease in hematocrit and the levels of Cl and hemoglobin. No effects on blood physiology were observed in fish exposed to the lower concentrations of TNT (1-100μg/L). TNT and the metabolites 2-amino-4,6-dinitrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT) were found in the muscle tissue, whereas only 2-ADNT and 4-ADNT were found in the bile. The rapid excretion and estimated bioconcentration factors (range of 2-18 after 48h in gills, blood, liver, kidney, muscle and brain) indicated a low potential for bioaccumulation of TNT. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of surface energy on the shock properties of granular explosives

Science.gov (United States)

Bidault, X.; Pineau, N.

2018-01-01

This paper presents the first part of a two-fold molecular dynamics study of the impact of the granularity on the shock properties of high explosives. Recent experimental studies show that the granularity can have a substantial impact on the properties of detonation products {i.e., variations in the size distributions of detonation nanodiamonds [V. Pichot et al., Sci. Rep. 3, 2159 (2013)]}. These variations can have two origins: the surface energy, which is a priori enhanced from micro- to nano-scale, and the porosity induced by the granular structure. In this first report, we study the impact of the surface-energy contribution on the inert shock compression of TATB, TNT, α-RDX, and β-HMX nano-grains (triaminotrinitrobenzene, trinitrotoluene, hexogen and octogen, respectively). We compute the radius-dependent surface energy and combine it with an ab initio-based equation of state in order to obtain the resulting shock properties through the Rankine-Hugoniot relations. We find that the enhancement of the surface energy results in a moderate overheating under shock compression. This contribution is minor with respect to porosity, when compared to a simple macroscopic model. This result motivates further atomistic studies on the impact of nanoporosity networks on the shock properties.

Shock-induced fast reactions of zinc nanoparticles and RDX

International Nuclear Information System (INIS)

Xue Mian; Wu Jinghe; Ye Song; Yang Xiangdong; Hu Dong; Wang Yanping; Zhu Wenjun; Li Chengbing

2008-01-01

Fast reactions of zinc nanoparticles and RDX were investigated in normal incident shock waves. The emergence time and emission spectra intensity of partial products such as NO 2 , H, C 2 , O, CO, CH 2 O, CO 2 , H 2 O and ZnO were observed by a TDS5054 oscilloscope. The results indicate that NO 2 appears first in each experiment, which is in agreement with the theoretical results. The addition of zinc nanoparticles to RDX can not only shorten the ignition delay time by 20% but also double the shockwave diffusion velocity to 2180 ± 50 m s -1 and triple the temperature to 2020 ± 60 K. The emergence time of products shortens by around 10-40% and the emission spectra intensity of H 2 O and CH 2 O rises by about three times and one times, respectively. CO 2 , H 2 O and O 2 in various concentrations were introduced into the zinc-RDX reaction, respectively, which indicate that O 2 made the ignition delay time shorten by over 30%, the effect of H 2 O was not prominent while CO 2 made the ignition delay time lag by around 30%. The results indicate that the Zn-O 2 reaction mainly occurs in O 2 , CO 2 and H 2 O

Chemical Selectivity and Sensitivity of a 16-Channel Electronic Nose for Trace Vapour Detection

Directory of Open Access Journals (Sweden)

Drago Strle

2017-12-01

Full Text Available Good chemical selectivity of sensors for detecting vapour traces of targeted molecules is vital to reliable detection systems for explosives and other harmful materials. We present the design, construction and measurements of the electronic response of a 16 channel electronic nose based on 16 differential microcapacitors, which were surface-functionalized by different silanes. The e-nose detects less than 1 molecule of TNT out of 10+12 N2 molecules in a carrier gas in 1 s. Differently silanized sensors give different responses to different molecules. Electronic responses are presented for TNT, RDX, DNT, H2S, HCN, FeS, NH3, propane, methanol, acetone, ethanol, methane, toluene and water. We consider the number density of these molecules and find that silane surfaces show extreme affinity for attracting molecules of TNT, DNT and RDX. The probability to bind these molecules and form a surface-adsorbate is typically 10+7 times larger than the probability to bind water molecules, for example. We present a matrix of responses of differently functionalized microcapacitors and we propose that chemical selectivity of multichannel e-nose could be enhanced by using artificial intelligence deep learning methods.

Application of 13C and 15N stable isotope probing to characterize RDX degrading microbial communities under different electron-accepting conditions

International Nuclear Information System (INIS)

Cho, Kun-Ching; Lee, Do Gyun; Fuller, Mark E.; Hatzinger, Paul B.; Condee, Charles W.; Chu, Kung-Hui

2015-01-01

Highlights: • SIP characterized RDX-degrading communities under different e-accepting conditions. • Dominant RDX degradation pathways differed under different e-accepting conditions. • More complete detoxification of RDX occurred under methanogenic and sulfate-reducing conditions than under manganese(IV) and iron(III)-reducing conditions. - Abstract: This study identified microorganisms capable of using the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) or its metabolites as carbon and/or nitrogen sources under different electron-accepting conditions using 13 C and 15 N stable isotope probing (SIP). Mesocosms were constructed using groundwater and aquifer solids from an RDX-contaminated aquifer. The mesocosms received succinate as a carbon source and one of four electron acceptors (nitrate, manganese(IV), iron(III), or sulfate) or no additional electron acceptor (to stimulate methanogenesis). When RDX degradation was observed, subsamples from each mesocosm were removed and amended with 13 C 3 - or ring- 15 N 3 -, nitro- 15 N 3 -, or fully-labeled 15 N 6 -RDX, followed by additional incubation and isolation of labeled nucleic acids. A total of fifteen 16S rRNA sequences, clustering in α- and γ-Proteobacteria, Clostridia, and Actinobacteria, were detected in the 13 C-DNA fractions. A total of twenty seven sequences were derived from different 15 N-DNA fractions, with the sequences clustered in α- and γ-Proteobacteria, and Clostridia. Interestingly, sequences identified as Desulfosporosinus sp. (in the Clostridia) were not only observed to incorporate the labeled 13 C or 15 N from labeled RDX, but also were detected under each of the different electron-accepting conditions. The data suggest that 13 C- and 15 N-SIP can be used to characterize microbial communities involved in RDX biodegradation, and that the dominant pathway of RDX biodegradation may differ under different electron-accepting conditions

Effects of hydrogen bonds on solid state TATB, RDX, and DATB under high pressures

International Nuclear Information System (INIS)

Guo Feng; Hu Hai-Quan; Zhang Hong; Cheng Xin-Lu

2014-01-01

To probe the behavior of hydrogen bonds in solid energetic materials, we conduct ReaxFF and SCC–DFTB molecular dynamics simulations of crystalline TATB, RDX, and DATB. By comparing the intra- and inter-molecular hydrogen bonding rates, we find that the crystal structures are stabilized by inter-molecular hydrogen bond networks. Under high-pressure, the inter- and intra-molecular hydrogen bonds in solid TATB and DATB are nearly equivalent. The hydrogen bonds in solid TATB and DATB are much shorter than in solid RDX, which suggests strong hydrogen bond interactions existing in these energetic materials. Stretching of the C–H bond is observed in solid RDX, which may lead to further decomposition and even detonation. (condensed matter: structural, mechanical, and thermal properties)

Gasdynamic Model of Turbulent Combustion in TNT Explosions

Energy Technology Data Exchange (ETDEWEB)

Kuhl, A L; Bell, J B; Beckner, V E

2010-01-08

A model is proposed to simulate turbulent combustion in confined TNT explosions. It is based on: (i) the multi-component gasdynamic conservation laws, (ii) a fast-chemistry model for TNT-air combustion, (iii) a thermodynamic model for frozen reactants and equilibrium products, (iv) a high-order Godunov scheme providing a non-diffusive solution of the governing equations, and (v) an ILES approach whereby adaptive mesh refinement is used to capture the energy bearing scales of the turbulence on the grid. Three-dimensional numerical simulations of explosion fields from 1.5-g PETN/TNT charges were performed. Explosions in six different chambers were studied: three calorimeters (volumes of 6.6-l, 21.2-l and 40.5-l with L/D = 1), and three tunnels (L/D = 3.8, 4.65 and 12.5 with volumes of 6.3-l) - to investigate the influence of chamber volume and geometry on the combustion process. Predicted pressures histories were quite similar to measured pressure histories for all cases studied. Experimentally, mass fraction of products, Y{sub p}{sup exp}, reached a peak value of 88% at an excess air ratio of twice stoichiometric, and then decayed with increasing air dilution; mass fractions Y{sub p}{sup calc} computed from the numerical simulations followed similar trends. Based on this agreement, we conclude that the dominant effect that controls the rate of TNT combustion with air is the turbulent mixing rate; the ILES approach along with the fast-chemistry model used here adequately captures this effect.

Uptake of 2,4,6-Trinitrotoluene (TNT) by Vetiver grass (Vetiviera ziznoides L.) -- Preliminary results from a hydroponic study

Science.gov (United States)

Shakya, K. M.; Sarkar, D.; Datta, R.; Makris, K.; Pachanoor, D.

2006-05-01

2,4,6-Trinitrotoluene(TNT) is a potent mutagen and a Group C human carcinogen that has been widely used to produce munitions and explosives. As a result, vast areas that have been previously used as military ranges, munition burning and open detonation sites have been heavily contaminated with TNT. Conventional remedial activities in such contaminated sites commonly rely on methods such as incineration, land filling and soil composting. Phytoremediation offers a cost-effective solution, utilizing plants to phytoextract TNT from the contaminated soil. We propose the use of vetiver grass (Vetiveria zizanoides) to remove TNT from such contaminated soils. Vetiver is a fast-growing and adaptive grass, enabling its use in TNT-contaminated sites in a wide variety of soil types and climate. We also hypothesized that TNT removal by vetiver grass will be enhanced by utilizing a chaotropic agent (urea) to alter rhizosphere/root hair chemical environment. The objectives of this preliminary hydroponic study were: i) to investigate the effectiveness of vetiver grass in removing TNT from solution, and ii) to evaluate the use of a common agrochemical (urea) in enhancing TNT removal by vetiver grass. Vetiver plants were grown in a hydroponic system with five different TNT concentrations (0, 5, 10, 25, and 50 mg TNT L-1) and three urea concentrations (0, 0.01 and 0.1%). A plant density of 10 g L-1 and three replicate vessels per treatment were used. Aliquots were collected at several time intervals up to 192 hour, and were analyzed for TNT with HPLC. Results showed that vetiver was able to remove TNT from hydroponic solutions. The overall magnitude and kinetics of TNT removal by vetiver grass was enhanced in the presence of urea. TNT removal kinetics depended on TNT and urea initial concentrations, suggestive of second-order kinetic reactions. Preliminary results are encouraging, but in need for verification using more detailed studies involving TNT-contaminated soils. Ongoing

Editorial: Trends in Nanotechnology (TNT2005)

Science.gov (United States)

Correia, Antonio; Serena, Pedro A.; José Saenz, Juan; Reifenberger, Ron; Ordejón, Pablo

2006-05-01

This special issue of physica status solidi (a) presents representative contributions describing the main topics covered at the sixth Trends in Nanotechnology (TNT2005) International Conference, held in Oviedo (Spain), 29 August-2 September 2005.During the last years many international or national conferences have emerged in response to the growing awareness of the importance of nanotechnology as key issue for the future scientific and technological development. Among these, the conference series Trends in Nanotechnology has become one of the most important meeting points in the nanotechnology field: it provides fresh organisation ideas, brings together well known speakers, and promotes a suitable environment for discussions, exchanging ideas, enhancing scientific and personal relations among participants. TNT2005 was organised in a similar way to the five prior TNT conferences, with an impressive scientific programme including 40 Keynote lectures and two Nobel prizes, without parallel sessions, covering a wide spectrum of Nanotechnology research. In 2005, more than 360 scientists worldwide attended this event and contributed with more than 60 oral contributions and 250 posters, stimulating discussions about their most recent research.The aim of the conference was to focus on the applications of Nanotechnology and to bring together, in a scientific forum, various worldwide groups belonging to industry, universities and government institutions. TNT2005 was particularly effective at transmitting information and establishing contacts among workers in this field. Graduate students attending such conferences have understood the importance of interdisciplinary skills to afford their future research lines. 76 graduate students received a grant allowing them to present their work. 28 prizes to the best posters were awarded during this event. We would like to thank all the participants for their assistance, as well as the authors for their written contributions.TNT2005 is

Passive Biobarrier for Treating Co-mingled Perchlorate and RDX in Groundwater at an Active Range

Science.gov (United States)

2016-05-12

16S rRNA sequences were derived. These sequences resided in four major clusters: Actinobacteria (Eggerthella), -Proteobacteria (unclassified...Proteobacteria, Actinobacteria , -Proteobacteria and Clostridia) have been previously reported to biodegrade RDX directly, or to contribute to RDX...detected primarily under manganese-reducing conditions (with one under sulfate- reducing conditions) in our study, remain unclear. Actinobacteria are

Reactive simulation of the chemistry behind the condensed-phase ignition of RDX from hot spots.

Science.gov (United States)

Joshi, Kaushik L; Chaudhuri, Santanu

2015-07-28

Chemical events that lead to thermal initiation and spontaneous ignition of the high-pressure phase of RDX are presented using reactive molecular dynamics simulations. In order to initiate the chemistry behind thermal ignition, approximately 5% of RDX crystal is subjected to a constant temperature thermal pulse for various time durations to create a hot spot. After application of the thermal pulse, the ensuing chemical evolution of the system is monitored using reactive molecular dynamics under adiabatic conditions. Thermal pulses lasting longer than certain time durations lead to the spontaneous ignition of RDX after an incubation period. For cases where the ignition is observed, the incubation period is dominated by intermolecular and intramolecular hydrogen transfer reactions. Contrary to the widely accepted unimolecular models of initiation chemistry, N-N bond dissociations that produce NO2 species are suppressed in the condensed phase. The gradual temperature and pressure increase in the incubation period is accompanied by the accumulation of short-lived, heavier polyradicals. The polyradicals contain intact triazine rings from the RDX molecules. At certain temperatures and pressures, the polyradicals undergo ring-opening reactions, which fuel a series of rapid exothermic chemical reactions leading to a thermal runaway regime with stable gas-products such as N2, H2O and CO2. The evolution of the RDX crystal throughout the thermal initiation, incubation and thermal runaway phases observed in the reactive simulations contains a rich diversity of condensed-phase chemistry of nitramines under high-temperature/pressure conditions.

Shock-induced fast reactions of zinc nanoparticles and RDX

Energy Technology Data Exchange (ETDEWEB)

Xue Mian; Wu Jinghe; Ye Song; Yang Xiangdong [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China); Hu Dong; Wang Yanping; Zhu Wenjun; Li Chengbing [National Key Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid Physics, CAEP, Mianyang 621900 (China)], E-mail: mi-anxue@163.com

2008-02-21

Fast reactions of zinc nanoparticles and RDX were investigated in normal incident shock waves. The emergence time and emission spectra intensity of partial products such as NO{sub 2}, H, C{sub 2}, O, CO, CH{sub 2}O, CO{sub 2}, H{sub 2}O and ZnO were observed by a TDS5054 oscilloscope. The results indicate that NO{sub 2} appears first in each experiment, which is in agreement with the theoretical results. The addition of zinc nanoparticles to RDX can not only shorten the ignition delay time by 20% but also double the shockwave diffusion velocity to 2180 {+-} 50 m s{sup -1} and triple the temperature to 2020 {+-} 60 K. The emergence time of products shortens by around 10-40% and the emission spectra intensity of H{sub 2}O and CH{sub 2}O rises by about three times and one times, respectively. CO{sub 2}, H{sub 2}O and O{sub 2} in various concentrations were introduced into the zinc-RDX reaction, respectively, which indicate that O{sub 2} made the ignition delay time shorten by over 30%, the effect of H{sub 2}O was not prominent while CO{sub 2} made the ignition delay time lag by around 30%. The results indicate that the Zn-O{sub 2} reaction mainly occurs in O{sub 2}, CO{sub 2} and H{sub 2}O.

Algorithm describing pressure distribution of non-contact TNT explosion

Directory of Open Access Journals (Sweden)

Radosław Kiciński

2014-12-01

Full Text Available [b]Abstract[/b]. The aim of this study is to develop a computational algorithm, describing the shock wave pressure distribution in the space induced by non-contact TNT explosion. The procedure describes pressure distribution on a damp surface of the hull. Simulations have been carried out using Abaqus/CAE. The study also shows the pressure waveform descriptions provided by various authors and presents them in charts. The formulated conclusions convince efficiency of the algorithm application.[b]Keywords:[/b] Underwater explosion, shock wave, CAE, TNT, Kobben class submarine

The Biodegradation of TNT in Enhanced Soil and Compost Systems

Science.gov (United States)

1978-01-01

dimethylsulfoxide ( DMSO ) Is substituted for EDA because EDA tends to clog the sprayei . Dr. Chandler’s solvent system No. 1 is used for non-polar separa...material was converted to non- solvent -extractable, water-soluble materials of unknown Identity. These materials may represent the contents of dead... solvent system No. 1 54 2A TLC separation of TNT and derivatives using ChandlerIs solvent system No. 2 55 3A TLC separation of TNT and derivatives using

Differential thermal analysis microsystem for explosive detection

DEFF Research Database (Denmark)

Olsen, Jesper Kenneth; Greve, Anders; Senesac, L.

2011-01-01

as a small silicon nitride membrane incorporating heater elements and a temperature measurement resistor. In this manuscript the DTA system is described and tested by measuring calorimetric response of 3 different kinds of explosives (TNT, RDX and PETN). This project is carried out under the framework...

Assessment of the TNT- and AMPA-Induced Changes in Vegetation Morphology and Bio-physical Properties

Science.gov (United States)

Campbell, P. K.; Middleton, E.; Corp, L.

2009-12-01

Currently, there is no satisfactory method for locating unexploded ordinance or to mitigate the environmental impacts of leaked TNT. Non-exploded TNT-containing land mines deployed during military training exercises eventually leak TNT into the soils, where it is partially degraded into nitrate and toluene, a carcinogen. Environmental stresses alter plant physiology, affecting photosynthesis as well as the production of protective chemicals such as phenolic compounds which fluoresce in the blue/green spectrum. Changes in the fluorescence and reflectance spectral signatures of vegetation occur concurrently with the changes in plant vigor and chemical constituents. Thus, monitoring of vegetation vigor based on fluorescence and reflectance measurements could provide the means for detecting contamination from trinitrotoluene (TNT), a common compound contained in land mines. The goal of this study was to evaluate the capability of fluorescence sensing systems to remotely detect the presence of TNT-related compounds sequestered in vegetation growing on TNT contaminated soils. Using instrumentation and methodologies that utilize reflectance and actively induced fluorescence associated with “stead-state” emissions, we conducted experiments on four experimental species - two of which have the C4 photosynthetic pathway and two of which have the more common C3 pathway. The experimental plants were grown outdoors in 2 gallon pots in a 75:25 mixture of white quartz sand and perlite, with planted pots placed in larger pots to retain water and TNT solution added. Plants were randomly assigned to treatments for twice weekly applications of 0, 10, and 20 μl/l TNT solutions [doses ~30 μl/l are toxic] and watered daily as necessary. Our findings, using ChlF spectra, indicate statistically significant differences between TNT treated and control samples in the blue and green regions. Maximum treatment separation was achieved using 280Ex and measuring emissions in the blue

Effects of additives on 2,4,6-trinitrotoluene (TNT) removal and its mineralization in aqueous solution by gamma irradiation

International Nuclear Information System (INIS)

Lee, Byungjin; Jeong, Seung-Woo

2009-01-01

The effects of additives (i.e., methanol, EDTA, mannitol, thiourea, nitrous oxide, oxygen and ozone) on gamma irradiation of 2,4,6-trinitrotoluene (TNT) were investigated to elucidate the initial reaction mechanism of TNT degradation and suggest an practical method for complete by-product removal. All additives, except thiourea, significantly increased the TNT removal efficiency by gamma irradiation. The overall results of the additive experiments implied that the TNT decomposition would be initiated by ·OH, e aq - , and HO 2 ·/O 2 · - , and also implied that ·H did not have any direct effect on the TNT decomposition. Additions of methanol and nitrous oxide were more effective in TNT removal than the other additives, achieving complete removal of TNT at doses below 20 kGy. Total organic carbon (TOC) of the irradiated solution was analyzed to evaluate the degree of TNT mineralization under the additive conditions. TOC under the nitrous oxide addition was removed rapidly, and complete TNT mineralization was thus achieved at 50 kGy. Methanol addition was very effective in the TNT removal, but it was not effective in reduction in TOC. Trinitrobenzene (TNB), oxalic acid and glyoxalic acid were detected as radiolytic organic by-products, while ammonia and nitrate were detected as radiolytic inorganic by-products. The most efficient TNT removal and its mineralization by gamma irradiation would be achieved by supersaturating the solution with nitrous oxide before irradiation.

High-resolution Raman Spectroscopy for the Nanostructural Characterization of Explosive Nanodiamond Precursors.

Science.gov (United States)

Deckert-Gaudig, Tanja; Pichot, Vincent; Spitzer, Denis; Deckert, Volker

2017-01-18

The specific attributes of nanodiamonds have attracted increasing interest for electronics or biomedical applications. An efficient synthetic route towards nanodiamonds is via detonation of hexolite (i.e. a mixture of TNT [2,4,6-trinitrotoluene] and RDX [1,3,5-trinitro-1,3,5-triazine]). In particular, detonation of hexolite crystallized by spray flash evaporation (SFE) yields extremely small diamonds (<4 nm). To unravel the detonation mechanism, a structural characterization of the explosives is required but is challenging due to their thermal instability. We demonstrate a combination of conventional Raman spectroscopy and tip-enhanced Raman spectroscopy (TERS) for resolving morphological and structural differences of differently prepared hexolite nanocomposites. The experiments allow for the first time a structural differentiation of individual TNT and RDX crystals and 15-20 nm sized core-shell structures, consequently providing a general approach to investigate the actual composition of mixtures on the nanometer scale. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Honey bees (Apis mellifera) as explosives detectors: exploring proboscis extension reflex conditioned response to trinitrotolulene (TNT)

Energy Technology Data Exchange (ETDEWEB)

Taylor-mccabe, Kirsten J [Los Alamos National Laboratory; Wingo, Robert M [Los Alamos National Laboratory; Haarmann, Timothy K [Los Alamos National Laboratory

2008-01-01

We examined honey bee's associative learning response to conditioning with trinitrotolulene (TNT) vapor concentrations generated at three temperatures and their ability to be reconditioned after a 24 h period. We used classical conditioning of the proboscis extension (PER) in honey bees using TNT vapors as the conditioned stimulus and sucrose as the unconditioned stimulus. We conducted fifteen experimental trials with an explosives vapor generator set at 43 C, 25 C and 5 C, producing three concentrations of explosives (1070 ppt, 57 ppt, and 11 ppt). Our objective was to test the honey bee's ability to exhibit a conditioned response to TNT vapors at all three concentrations by comparing the mean percentage of honey bees successfully exhibiting a conditioned response within each temperature group. Furthermore, we conducted eight experimental trials to test the honey bee's ability to retain their ability to exhibit a conditioned response to TNT after 24h period by comparing the mean percentage of honey bees with a conditioned response TNT on the first day compared to the percentage of honey bees with a conditioned response to TNT on the second day. Results indicate that there was no significant difference between the mean percentage of honey bees with a conditioned response to TNT vapors between three temperature groups. There was a significant difference between the percentage of honey bees exhibiting conditioned response on the first day of training compared to the percentage of honey bees exhibiting conditioned response 24 h after training. Our experimental results indicate that honey bees can be trained to exhibit a conditioned response to a range of TNT concentrations via PER However, it appears that the honey bee's ability to retain the conditioned response to TNT vapors after 24h significantly decreases.

CFD SIMULATION FOR DEMILITARIZATION OF RDX IN A ROTARY KILN BY THERMAL DECOMPOSITION

Directory of Open Access Journals (Sweden)

SI H. LEE

2017-06-01

Full Text Available Demilitarization requires the recovery and disposal of obsolete ammunition and explosives. Since open burning/detonation of hazardous waste has caused serious environmental and safety problems, thermal decomposition has emerged as one of the most feasible methods. RDX is widely used as a military explosive due to its high melting temperature and detonation power. In this work, the feasible conditions under which explosives can be safely incinerated have been investigated via a rotary kiln simulation. To solve this problem, phase change along with the reactions of RDX has been incisively analyzed. A global reaction mechanism consisting of condensed phase and gas phase reactions are used in Computational Fluid Dynamics simulation. User Defined Functions in FLUENT is utilized in this study to inculcate the reactions and phase change into the simulation. The results divulge the effect of temperature and the varying amounts of gas produced in the rotary kiln during the thermal decomposition of RDX. The result leads to the prospect of demilitarizing waste explosives to avoid the possibility of detonation.

Localization of 131I-chTNT in a nude mice model with human hepatoma

International Nuclear Information System (INIS)

Chen Shaoliang; Sun Xiaoguang; Xiu Yan; Zhong Gaoren; Qiao Weiwei; Xu Lanwen; Li Wenzheng

1998-01-01

Purpose: In order to evaluate the targeting activity in the animal model with human hepatoma, the 131 I-chTNT radioimmunoimaging was explored. Methods: Radioimmunoimages were taken on different intervals after injection of 131 I-chTNT 5.55 MBq to the nude mice, and tissue distribution was measured. The results of 131 I-chTNT monoclonal antibody group were compared with that of 131 I control group. Results: The experimental group developed tumor positive images after one day of radio-labelled monoclonal antibodies injection and held on until the end of the experiment. The radioactivity in tumor mass was stable, and the half life of 131 I-chTNT in hepatoma mass was 6.0 +- 1.6 days. there was no special radioactivity accumulation in normal liver tissue in the nude mice and the radioactivity in it disappeared rapidly. Statistics indicated the tumor/liver ratio in 1, 2, 3, 5, 7 days were 1.03, 2.43, 5.71, 7.96, 10.67, respectively. Conclusions: The results suggest that 131 I-chTNT monoclonal antibody has a considerable targeting activity, and provide an evidence for that it can be used as a new radiopharmaceutical agent for the imaging and radio therapy of hepatoma

Computer simulation for prediction of performance and thermodynamic parameters of high energy materials

International Nuclear Information System (INIS)

Muthurajan, H.; Sivabalan, R.; Talawar, M.B.; Asthana, S.N.

2004-01-01

A new code viz., Linear Output Thermodynamic User-friendly Software for Energetic Systems (LOTUSES) developed during this work predicts the theoretical performance parameters such as density, detonation factor, velocity of detonation, detonation pressure and thermodynamic properties such as heat of detonation, heat of explosion, volume of explosion gaseous products. The same code also assists in the prediction of possible explosive decomposition products after explosion and power index. The developed code has been validated by calculating the parameters of standard explosives such as TNT, PETN, RDX, and HMX. Theoretically predicated parameters are accurate to the order of ±5% deviation. To the best of our knowledge, no such code is reported in literature which can predict a wide range of characteristics of known/unknown explosives with minimum input parameters. The code can be used to obtain thermochemical and performance parameters of high energy materials (HEMs) with reasonable accuracy. The code has been developed in Visual Basic having enhanced windows environment, and thereby advantages over the conventional codes, written in Fortran. The theoretically predicted HEMs performance can be directly printed as well as stored in text (.txt) or HTML (.htm) or Microsoft Word (.doc) or Adobe Acrobat (.pdf) format in the hard disk. The output can also be copied into the Random Access Memory as clipboard text which can be imported/pasted in other software as in the case of other codes

Organic pollutants removal from 2,4,6-trinitrotoluene (TNT) red water using low cost activated coke

Institute of Scientific and Technical Information of China (English)

Mohe Zhang; Quanlin Zhao; Zhengfang Ye

2011-01-01

We treated 2,4,6-trinitrotoluene (TNT) red water from the Chinese explosive industry with activated coke (AC) from lignite.Since the composition of TNT red water was very complicated,chemical oxygen demand (COD) was used as the index for evaluating treatment efficiency.This study focused on sorption kinetics and equilibrium sorption isotherms of AC for the removal of COD from TNT red water,and the changes of water quality before and after adsorption were evaluated using high performance liquid chromatography,UV-Vis spectra and gas chromatography/mass spectroscopy.The results showed that the sorption kinetics of COD removal from TNT red water onto AC fitted well with the pseudo second-order model.The adsorption process was an exothermic and physical process.The sorption isotherm was in good agreement with Redlich-Peterson isotherm.At the conditions of initial pH =6.28,20°C and 3 hr of agitation,under 160 g/L AC,64.8% of COD was removed.The removal efficiencies of 2,4-dinitrotoluene-3-sulfonate (2,4-DNT-3-SO3-) and 2,4-dinitrotoluene-5-sulfonate (2,4-DNT-5-SO3-) were 80.5% and 84.3%,respectively.After adsorption,the acute toxicity of TNT red water reduced greatly,compared with that of unprocessed TNT red water.

Integrated Data Collection Analysis (IDCA) Program — RDX Standard Data Sets

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorensen, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Phillips, Jason J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Shelley, Timothy J. [Bureau of Alcohol, Tobacco and Firearms, Huntsville, AL (United States); Reyes, Jose A. [Applied Research Associates, Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2013-03-04

The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small- Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of the RDX Type II Class 5 standard, for a third and fourth time in the Proficiency Test and averaged with the analysis results from the first and second time. The results, from averaging all four sets (1, 2, 3 and 4) of data suggest a material to have slightly more impact sensitivity, more BAM friction sensitivity, less ABL friction sensitivity, similar ESD sensitivity, and same DSC sensitivity, compared to the results from Set 1, which was used previously as the values for the RDX standard in IDCA Analysis Reports.

A Nanosensor for TNT Detection Based on Molecularly Imprinted Polymers and Surface Enhanced Raman Scattering

Directory of Open Access Journals (Sweden)

Mikella E. Hankus

2011-03-01

Full Text Available We report on a new sensor strategy that integrates molecularly imprinted polymers (MIPs with surface enhanced Raman scattering (SERS. The sensor was developed to detect the explosive, 2,4,6-trinitrotoluene (TNT. Micron thick films of sol gel-derived xerogels were deposited on a SERS-active surface as the sensing layer. Xerogels were molecularly imprinted for TNT using non-covalent interactions with the polymer matrix. Binding of the TNT within the polymer matrix results in unique SERS bands, which allow for detection and identification of the molecule in the MIP. This MIP-SERS sensor exhibits an apparent dissociation constant of (2.3 ± 0.3 × 10−5 M for TNT and a 3 µM detection limit. The response to TNT is reversible and the sensor is stable for at least 6 months. Key challenges, including developing a MIP formulation that is stable and integrated with the SERS substrate, and ensuring the MIP does not mask the spectral features of the target analyte through SERS polymer background, were successfully met. The results also suggest the MIP-SERS protocol can be extended to other target analytes of interest.

Determination of TNT explosive based on its selectively interaction with creatinine-capped CdSe/ZnS quantum dots

International Nuclear Information System (INIS)

Carrillo-Carrión, Carolina; Simonet, Bartolomé M.; Valcárcel, Miguel

2013-01-01

Graphical abstract: -- Highlights: •Creatinine-modified CdSe/ZnS quantum dots fluorescent probe has been prepared. •This modified QDs has been used for sensing 2,4,6,-trinitrotoluene explosive (TNT). •The selectivity of fluorescence quenching of creatinine-QD for TNT has been evaluated. •The potential application of the proposed methodology for the determination of TNT in spiked soils has been demonstrated. -- Abstract: Here, a creatinine-modified CdSe/ZnS quantum dots fluorescent probe has been prepared and used for sensing 2,4,6,-trinitrotoluene explosive (TNT). The proposed method is based on the selective interaction between creatinine and nitroaromatic compounds according to the well-known Jaffé reaction. The procedure for the synthesis of creatinine-CdSe/ZnS reagent is very simple and reproducible and its fluorescent characteristics are reported. We found that the presence of TNT quenches the original fluorescence of creatinine-QD according to the Stern–Volmer model. Under the working conditions, the calibration plot of I o /I versus concentration of TNT was linear in the range 10–300 μg L −1 (R 2 = 0.996). The mechanism interaction is discussed. The selectivity of fluorescence quenching of creatinine-QD for TNT has been evaluated. Finally, the potential application of the proposed methodology for the determination of TNT in spiked soils is demonstrated. For the analysis of soil samples a solid-liquid extraction is carried out and a four-point standard addition protocol is used to correct the matrix effect. The method, which is simple and rapid, allows the detection of 0.057 μg g −1 of TNT in soil samples. This sensor could be a useful tool for environmental studies, a crucial topic for nanotechnology nowadays

BIOTRANSFORMATION OF 2,4,6-TRINITROTOLUENE (TNT) BY A PLANT-ASSOCIATED FUNGUS FUSARIUM OXYSPORUM

Science.gov (United States)

The capability of a plant-associated fungus, Fusarium oxyvorum, to transform TNT in liquid cultures was investigated. TNT was transformed into 2-amino-4, 6-dinitrotoluene (2-A-DNT), 4-amino-2, 6-dinitrotoluene (4-A- DNT), and 2, 4-diamino-6-nitrotoluene (2, 4-DAT) via 2- and 4-hy...

Coefficients of sliding friction of single crystals of high explosives under different rubbing conditions

International Nuclear Information System (INIS)

Wu, Y Q; Chaudhri, M Munawar

2013-01-01

The coefficients of sliding friction of single crystals of commonly used high explosives pentaerythritol tetranitrate (PETN), cyclotrimethylene trinitramine (RDX) and beta-cyclotetramethylene tetranitramine (β-HMX) under several rubbing configurations and at a relative sliding speed of 0.22 mm s -1 were measured. The sliding configurations were (1) crystal-polished steel pairs, (2) like-crystal pairs and (3) unlike-crystal pairs. For every rubbing configuration the friction force showed oscillations, which are thought to be caused by the formation and shearing of the adhesive junctions formed at the surface of the rubbing crystals. This shearing of the adhesive junctions led to the formation of microscopic and sub-microscopic particles, which were confirmed by an environmental scanning electron microscope study. For every rubbing configuration and for relatively high normal loads pressing the rubbing crystals together, the coefficient of friction was generally in the range 0.2-0.25 and it has been concluded that the coefficient of friction is controlled by the adhesion with almost negligible contribution from the ploughing component. From a knowledge of the coefficient of friction and the uniaxial yield stress values of single crystals of RDX and β-HMX, the shear strength of these crystals were determined to be ∼13.4 MPa and ∼16.8 MPa, respectively.

The radioprotection problem in 131I-chTNT cancer therapy

International Nuclear Information System (INIS)

Chen Yangchun; Cheng Shaoliang; Gu Yucan; Shao Zhenghua; Li Beilei; Shi Hongchen

2004-01-01

Aim: Use of a mouse-human chimeric Tumor-Necrosis-Therapy (chTNT) monoclonal antibody has been considered for cancer therapy based on its potential for the radioimmunotherapy of many solid tumors. By estimating the total effective dose equivalent (EDE) to any other individual from exposure to the patient who containing 131 I-chTNT, we tried to determine when the patient could be released. Method: All urine samples were collected over the 168 h period infusion of 131 I-chTNT. The weight and radioactivity of urine collected at each micturition were determined specific activity was calculated, Anterior and posterior whole body imaging was performed at 0.5, 24, 48, 72, 120, 168 h after injection. We followed U.S. Nuclear Regulatory Commission, 1997, Regulatory Guide 8.39 to calculate the EDE to the public, assuming patients being released 7 days after infusion and the exposure time to patients' household members being 0.33 day, and to doctor or nurse being 0.08 or 0.33 day. Result: And as much as (33±9% of the administrated radioactivity was excreted in the urine within 168 h after administration. Its per cent injection dose time curve followed a one-exponential model, and its mean appearance half time value was (3.8±0.4) h. The whole body clearance of 131 I-chTNT also followed a one-exponential model, and its mean disappearance half time value was (4.1±0.4) h. The EDE was (0.18±0.01)μSv/MBq (when exposure time was 0.08 day) or (0.42±0.02)μSv/MBq (when exposure time was 0.33 day) for doctor or nurse, and (0.18±0.02)μSv/MBq for any other individual. When any patient accumulated containing 11100 MBq, the highest dose she or he can infuse, whose household members' EDE may be 2 mSv. And the doctor or nurse who use 131 I-chTNT for cancer therapy (exposure time is 0.08 day) is safety when the accumulated dose under 111000 MBq (3Ci). Conclusion: If we follow this cancer therapy plan, the EDE to the public per year will lower than the national standard. It is safety

Deflagration to Detonation Transition (DDT) Simulations of HMX Powder Using the HERMES Model

Science.gov (United States)

White, Bradley; Reaugh, John; Tringe, Joseph

2017-06-01

We performed computer simulations of DDT experiments with Class I HMX powder using the HERMES model (High Explosive Response to MEchanical Stimulus) in ALE3D. Parameters for the model were fitted to the limited available mechanical property data of the low-density powder, and to the Shock to Detonation Transition (SDT) test results. The DDT tests were carried out in steel-capped polycarbonate tubes. This arrangement permits direct observation of the event using both flash X-ray radiography and high speed camera imaging, and provides a stringent test of the model. We found the calculated detonation transition to be qualitatively similar to experiment. Through simulation we also explored the effects of confinement strength, the HMX particle size distribution and porosity on the computed detonation transition location. This work was performed under the auspices of the US DOE by LLNL under Contract DE-AC52-07NA27344.

Biotransformation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by a prospective consortium and its most effective isolate Serratia marcescens

Energy Technology Data Exchange (ETDEWEB)

Young, D.M.; Ogden, K.L. [Univ. of Arizona, Tucson, AZ (United States). Dept. of Chemical and Environmental Engineering; Unkefer, P.J. [Los Alamos National Lab., NM (United States). Chemical Science and Technology Div.

1997-03-05

The biotransformation of hexahydro-1,3,5-trinitro-1,3,5 triazine (RDX) has been observed in liquid culture by a consortium of bacteria found in horse manure. Five types of bacteria were found to predominate in the consortium and were isolated. The most effective of these isolates at transforming RDX was Serratia marcescens. The biotransformation of RDX by all of these bacteria was found to occur only in the anoxic stationary phase. The process of bacterial growth and RDX biotransformation was quantified for the purpose of developing a predictive type model. Cell growth was assumed to follow Monod kinetics. All of the aerobic and anoxid growth parameters were determined: {mu}{sub max}, K{sub s}, and Y{sub x/s}. RDX was found to competitively inhibit cell growth in both atmospheres. Degradation of RDX by Serratia marcescens was found to proceed through the stepwise reduction of the three nitro groups to nitroso groups. Each of these reductions was found to be first order in both component and cell concentrations. The degradation rate constant for the first step in this reduction process by the consortium was 0.022 L/g cells {center_dot} h compared to 0.033 L/g cells {center_dot} h for the most efficient isolate.

Thermal decomposition and kinetic evaluation of decanted 2,4,6-trinitrotoluene (TNT) for reutilization as composite material

Science.gov (United States)

Ahmed, M. F.; Hussain, A.; Malik, A. Q.

2016-08-01

Use of energetic materials has long been considered for only military purposes. However, it is very recent that their practical applications in wide range of commercial fields such as mining, road building, under water blasting and rocket propulsion system have been considered. About 5mg of 2,4,6-trinitrotoluene (TNT) in serviceable (Svc) as well as unserviceable (Unsvc) form were used for their thermal decomposition and kinetic parameters investigation. Thermogravimetric/ differential thermal analysis (TG/DTA), X-ray diffraction (XRD) and Scanning electron microscope (SEM) were used to characterize two types of TNT. Arrhenius kinetic parameters like activation energy (E) and enthalpy (AH) of both TNT samples were determined using TG curves with the help of Horowitz and Metzger method. Simultaneously, thermal decomposition range was evaluated from DTA curves. Distinct diffraction peaks showing crystalline nature were obtained from XRD analysis. SEM results indicated that Unsvc TNT contained a variety of defects like cracks and porosity. Similarly, it is observed that thermal as well as kinetic behavior of both TNT samples vary to a great extent. Likewise, a prominent change in the activation energies (E) of both samples is observed. This in-depth study provides a way forward in finding solutions for the safe reutilization of decanted TNT.

Integrating Paper Chromatography with Electrochemical Detection for the Trace Analysis of TNT in Soil

Directory of Open Access Journals (Sweden)

Patrick Ryan

2015-07-01

Full Text Available We report on the development of an electrochemical probe for the trace analysis of 2,4,6-trinitrotoluene (TNT in soil samples. The probe is a combination of graphite electrodes, filter paper, with ethylene glycol and choline chloride as the solvent/electrolyte. Square wave chromatovoltammograms show the probes have a sensitivity for TNT of 0.75 nA/ng and a limit of detection of 100 ng. In addition, by taking advantage of the inherent paper chromatography step, TNT can be separated in both time and cathodic peak potential from 4-amino-dinitrotolene co-spotted on the probe or in soil samples with the presence of methyl parathion as a possible interferent.

Importance of the gas phase role to the prediction of energetic material behavior: An experimental study

International Nuclear Information System (INIS)

Ali, A.N.; Son, S.F.; Asay, B.W.; Sander, R.K.

2005-01-01

Various thermal (radiative, conductive, and convective) initiation experiments are performed to demonstrate the importance of the gas phase role in combustion modeling of energetic materials (EM). A previously published condensed phase model that includes a predicted critical irradiance above which ignition is not possible is compared to experimental laser ignition results for octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and 2,4,6-trinitrotoluene (TNT). Experimental results conflict with the predicted critical irradiance concept. The failure of the model is believed to result from a misconception about the role of the gas phase in the ignition process of energetic materials. The model assumes that ignition occurs at the surface and that evolution of gases inhibits ignition. High speed video of laser ignition, oven cook-off and hot wire ignition experiments captures the ignition of HMX and TNT in the gas phase. A laser ignition gap test is performed to further evaluate the effect of gas phase laser absorption and gas phase disruption on the ignition process. Results indicate that gas phase absorption of the laser energy is probably not the primary factor governing the gas phase ignition observations. It is discovered that a critical gap between an HMX pellet and a salt window of 6 mm±0.4 mm exists below which ignition by CO 2 laser is not possible at the tested irradiances of 29 W/cm 2 and 38 W/cm 2 for HMX ignition. These observations demonstrate that a significant disruption of the gas phase, in certain scenarios, will inhibit ignition, independent of any condensed phase processes. These results underscore the importance of gas phase processes and illustrate that conditions can exist where simple condensed phase models are inadequate to accurately predict the behavior of energetic materials

Importance of the gas phase role to the prediction of energetic material behavior: An experimental study

Science.gov (United States)

Ali, A. N.; Son, S. F.; Asay, B. W.; Sander, R. K.

2005-03-01

Various thermal (radiative, conductive, and convective) initiation experiments are performed to demonstrate the importance of the gas phase role in combustion modeling of energetic materials (EM). A previously published condensed phase model that includes a predicted critical irradiance above which ignition is not possible is compared to experimental laser ignition results for octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and 2,4,6-trinitrotoluene (TNT). Experimental results conflict with the predicted critical irradiance concept. The failure of the model is believed to result from a misconception about the role of the gas phase in the ignition process of energetic materials. The model assumes that ignition occurs at the surface and that evolution of gases inhibits ignition. High speed video of laser ignition, oven cook-off and hot wire ignition experiments captures the ignition of HMX and TNT in the gas phase. A laser ignition gap test is performed to further evaluate the effect of gas phase laser absorption and gas phase disruption on the ignition process. Results indicate that gas phase absorption of the laser energy is probably not the primary factor governing the gas phase ignition observations. It is discovered that a critical gap between an HMX pellet and a salt window of 6mm±0.4mm exists below which ignition by CO2 laser is not possible at the tested irradiances of 29W /cm2 and 38W/cm2 for HMX ignition. These observations demonstrate that a significant disruption of the gas phase, in certain scenarios, will inhibit ignition, independent of any condensed phase processes. These results underscore the importance of gas phase processes and illustrate that conditions can exist where simple condensed phase models are inadequate to accurately predict the behavior of energetic materials.

Nano-CL-20/HMX Cocrystal Explosive for Significantly Reduced Mechanical Sensitivity

OpenAIRE

An, Chongwei; Li, Hequn; Ye, Baoyun; Wang, Jingyu

2017-01-01

Spray drying method was used to prepare cocrystals of hexanitrohexaazaisowurtzitane (CL-20) and cyclotetramethylene tetranitramine (HMX). Raw materials and cocrystals were characterized using scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, Raman spectroscopy, and Fourier transform infrared spectroscopy. Impact and friction sensitivity of cocrystals were tested and analyzed. Results show that, after preparation by spray drying method, microparticles were sph...

An Anti-C1s Monoclonal, TNT003, Inhibits Complement Activation Induced by Antibodies Against HLA.

Science.gov (United States)

Thomas, K A; Valenzuela, N M; Gjertson, D; Mulder, A; Fishbein, M C; Parry, G C; Panicker, S; Reed, E F

2015-08-01

Antibody-mediated rejection (AMR) of solid organ transplants (SOT) is characterized by damage triggered by donor-specific antibodies (DSA) binding donor Class I and II HLA (HLA-I and HLA-II) expressed on endothelial cells. While F(ab')2 portions of DSA cause cellular activation and proliferation, Fc regions activate the classical complement cascade, resulting in complement deposition and leukocyte recruitment, both hallmark features of AMR. We characterized the ability of an anti-C1s monoclonal antibody, TNT003, to inhibit HLA antibody (HLA-Ab)-induced complement activation. Complement deposition induced by HLA-Ab was evaluated using novel cell- and bead-based assays. Human aortic endothelial cells (HAEC) were cultured with HLA-Ab and human complement; production of activated complement proteins was measured by flow cytometry. Additionally, C3d deposition was measured on single antigen beads (SAB) mixed with HLA-Ab and human complement. TNT003 inhibited HLA-Ab mediated complement deposition on HAEC in a concentration-dependent manner; C3a, C4a and C5a anaphylatoxin production was also diminished by TNT003. Finally, TNT003 blocked C3d deposition induced by Class I (HLAI-Ab)- and Class II (HLAII-Ab)-specific antibodies on SAB. These data suggest TNT003 may be useful for modulating the effects of DSA, as TNT003 inhibits complement deposition and split product formation generated by HLA-I/II-Ab in vitro. © 2015 The Authors. American Journal of Transplantation Published by Wiley Periodicals, Inc.

Lon protease affects the RdxA nitroreductase activity and metronidazole susceptibility in Helicobacter pylori.

Science.gov (United States)

Tu, I-Fan; Liao, Jiahn-Haur; Yang, Feng-Ling; Lin, Nien-Tsung; Chan, Hong-Lin; Wu, Shih-Hsiung

2014-10-01

The lon gene of Helicobacter pylori strains is constitutively expressed during growth. However, virtually nothing is understood concerning the role of Lon in H. pylori. This study examined the function and physiological role of Lon in H. pylori (HpLon) using a trapping approach to identify putative Lon binding partners in the bacterium. Protease-deficient Lon was expressed and served as the bait in trapping approach to capture the interacting partners in H. pylori. The antibiotic susceptibility of wild-type and lon derivative mutants was determined by the E test trips and the disc diffusion assay. The effect of HpLon on RdxA activity was detected the change in NADPH oxidation and metronidazole reduction by spectrophotometer. Lon in Helicobacter pylori (HpLon) interacting partners are mostly associated with metronidazole activation. lon mutant presents more susceptible to metronidazole than that of the wild type, and this phenotype is recovered by complementation of the wild-type Lon. We found that the ATPases associated with a variety of cellular activities (AAA(+) ) module of HpLon causes a decrease in both NADPH oxidase and Mtz reductase activity in RdxA, a major Mtz-activating enzyme in H. pylori. Metronidazole resistance of H. pylori causes the serious medical problem worldwide. In this study, HpLon is involved in metronidazole susceptibility among H. pylori strains. We provide the evidence that HpLon alters RdxA activity in vitro. The decrease in metronidazole activation caused by HpLon is possibly prior to accumulate mutation in rdxA gene before the metronidazole-resistant strains to be occurred. © 2014 John Wiley & Sons Ltd.

Polarizability of acetanilide and RDX in the crystal: effect of molecular geometry

Science.gov (United States)

Tsiaousis, D.; Munn, R. W.; Smith, P. J.; Popelier, P. L. A.

2004-10-01

Density-functional theory with the B3LYP functional at the 6-311++G** level is used to calculate the dipole moment and the static polarizability for acetanilide and 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) in their in-crystal structures. For acetanilide the dipole moment is 2{1}/{2}% larger than for the gas-phase structure and for RDX (where there is a gross geometry change) it is 15% larger. The polarizability for the in-crystal structure is smaller than for the gas-phase structure by 3% for both species, whereas the in-crystal effective optical polarizability is larger than the gas-phase static polarizability for both crystals. Hence, effects in addition to the molecular geometry change in the crystal must be considered in order to interpret the effective polarizability completely.

TNT gaat op klantreis om tevredenheid te meten

NARCIS (Netherlands)

Jorritsma, A.

2010-01-01

Als we weten wat klanten ervaren en voelen, weten we ook wat we goed doen en waar de verbeterpunten zitten, hoe we de omzet kunnen laten groeien en kosten kunnen besparen. TNT Post omarmde de door TNO ontwikkelde 'Customer Journey' methode en ging op klantreis.

Mesoporous structured MIPs@CDs fluorescence sensor for highly sensitive detection of TNT.

Science.gov (United States)

Xu, Shoufang; Lu, Hongzhi

2016-11-15

A facile strategy was developed to prepare mesoporous structured molecularly imprinted polymers capped carbon dots (M-MIPs@CDs) fluorescence sensor for highly sensitive and selective determination of TNT. The strategy using amino-CDs directly as "functional monomer" for imprinting simplify the imprinting process and provide well recognition sites accessibility. The as-prepared M-MIPs@CDs sensor, using periodic mesoporous silica as imprinting matrix, and amino-CDs directly as "functional monomer", exhibited excellent selectivity and sensitivity toward TNT with detection limit of 17nM. The recycling process was sustainable for 10 times without obvious efficiency decrease. The feasibility of the developed method in real samples was successfully evaluated through the analysis of TNT in soil and water samples with satisfactory recoveries of 88.6-95.7%. The method proposed in this work was proved to be a convenient and practical way to prepare high sensitive and selective fluorescence MIPs@CDs sensors. Copyright © 2016 Elsevier B.V. All rights reserved.

Aminoxyl (nitroxyl) radicals in the early decomposition of the nitramine RDX.

Science.gov (United States)

Irikura, Karl K

2013-03-14

The explosive nitramine RDX (1,3,5-trinitrohexahydro-s-triazine) is thought to decompose largely by homolytic N-N bond cleavage, among other possible initiation reactions. Density-functional theory (DFT) calculations indicate that the resulting secondary aminyl (R2N·) radical can abstract an oxygen atom from NO2 or from a neighboring nitramine molecule, producing an aminoxyl (R2NO·) radical. Persistent aminoxyl radicals have been detected in electron-spin resonance (ESR) experiments and are consistent with autocatalytic "red oils" reported in the experimental literature. When the O-atom donor is a nitramine, a nitrosamine is formed along with the aminoxyl radical. Reactions of aminoxyl radicals can lead readily to the "oxy-s-triazine" product (as the s-triazine N-oxide) observed mass-spectrometrically by Behrens and co-workers. In addition to forming aminoxyl radicals, the initial aminyl radical can catalyze loss of HONO from RDX.

Peierls–Nabarro stresses of dislocations in monoclinic cyclotetramethylene tetranitramine (β-HMX)

Science.gov (United States)

Pal, Anirban; Picu, Catalin R.

2018-06-01

HMX (cyclotetramethylene tetranitramine) is an energetic material which releases substantial amounts of energy upon decomposition. The role of defects and deformation in causing reaction initiation was discussed in the literature but remains insufficiently understood. In this work, we identify, using computational methods, the slip systems which are potentially active in β-HMX and rank them in terms of their propensity for slip. To this end, we develop first a tentative ranking based on the degree of steric hindrance associated with slip. This is quantified using a geometric analog of the γ-surface. Further, we use atomistic models to compute the Peierls–Nabarro (PN) stress for the motion of dislocations in the slip systems with smallest degree of steric hindrance. A complex mechanical behavior is observed, including strong slip asymmetry, twinning and cleavage. The five systems with the lowest PN stress are (011)[01\\bar{1}], (011)[100], (101)[010], (101)[10\\bar{1}] and (021)[100]. We conclude that the material has enough slip systems available for supporting a generalized state of plastic strain provided the twinning system (101)[10\\bar{1}] is taken into consideration and that the resolved shear stress is at least 260 MPa.

Vibrational Spectrum of HMX at CO2 Laser Wavelengths: A Combined DRIFT and LPAS Study

Directory of Open Access Journals (Sweden)

A. Puiu

2012-01-01

Full Text Available The vibrational spectrum of solid standard HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine was investigated. Two spectroscopic techniques were adopted for their different sensitivity and resolution. A preliminary survey of the absorption bands of the compound was performed in the 8000–400 cm−1 spectral range by employing the diffuse reflectance infrared Fourier transform (DRIFT technique at room temperature. The high-resolution line spectrum of HMX was obtained in the 9.2–10.8 μm spectral range by laser photoacoustic spectroscopy (LPAS method, using a line tuneable 10 W stabilised cw CO2 laser light source. By comparing the data collected with the two techniques in the common frequency range, a very good agreement was observed.

Quasi-dynamic pressure and temperature

International Nuclear Information System (INIS)

Zaug, J M.; Farber, D L; Blosch, L L; Craig, I M; Hansen, D W; Aracne-Ruddle, C M; Shuh, D K

1998-01-01

The phase transformation of(beta)-HMX ( and lt; 0.5% RDX) to the(delta) phase has been studied for over twenty years and more recently with an optically sensitive second harmonic generation technique. Shock studies of the plastic binder composites of HMX have indicated that the transition is perhaps irreversible, a result that concurs with the static pressure results published by F. Goetz et al.[l] in 1978. However the stability field favors the(beta) polymorph over(delta) as pressure is increased (up to 5.4 GPa) along any sensible isotherm. In this experiment strict control of pressure and temperature is maintained while x-ray and optical diagnostics are applied to monitor the conformational dynamics of HMX. Unlike the temperature induced(beta) - and gt;(delta) transition, the pressure induced is heterogeneous in nature. The room pressure and temperature(delta) - and gt;(beta) transition is not immediate although it seems to occur over tens of hours. Transition points and kinetics are path dependent and so this paper describes our work in progress

Treatment of RDX and/or HMX Using Mulch Biowalls

Science.gov (United States)

2008-04-01

Cornhusker Army Ammunition Plant (CHAAP), Holston Army Ammunition Plant (HSAAP), Iowa Army Ammunition Plant (IAAP), Fort Meade, PCD, Raritan Arsenal ...0.01% 1 ɘ.001% 0.1% * i. Presence of other remediation technologies in the immediate vicinity No 4 No Yes, active phytoremediation in Pink Water...Concentrations of geochemical parameters such as inorganic anions (i.e., sulfate and nitrate) and cations (i.e., ferrous iron and arsenic ) were

Aluminum Agglomeration and Trajectory in Solid Rocket Motors

Science.gov (United States)

2007-08-30

34the stepwise oxidation of aluminum (that) is caused by the sequence of polymorphic phase transitions occurring in the growing oxide film",2 5 . 25...C. and Yang, V., "Analysis of RDX Monopropellant Combustion with Two-Phase Subsurface Reactions", Journal of Propulsion and Power, Vol. 11, No. 4...temperature. Generalized mechanisms have been developed and applied to many ingredients such as HMX , GAP, NG, BTTN, ADN and AP.10 The burning rates of

Toxicity and Metabolites of 2,4,6- Trinitrotoluene (TNT) in Plants and Worms from Exposure to Aged Soil

National Research Council Canada - National Science Library

Best, Elly

2004-01-01

.... Short-term exposure tests were conducted to explore the acute toxicity for the test organisms of TNT-spiked artificial soils and of the aged TNT-contaminated soil to be included in the subsequent...

Theoretical insight into the binding energy and detonation performance of ε-, γ-, β-CL-20 cocrystals with β-HMX, FOX-7, and DMF in different molar ratios, as well as electrostatic potential.

Science.gov (United States)

Feng, Rui-Zhi; Zhang, Shu-Hai; Ren, Fu-de; Gou, Rui-Jun; Gao, Li

2016-06-01

Molecular dynamics method was employed to study the binding energies on the selected crystal planes of the ε-, γ-, β-conformation 2,4,6,8,10,12-hexanitrohexaazaisowurtzitane (ε-, γ-, β-CL-20) cocrystal explosives with 1,1-diamino-2,2-dinitroethylene (FOX-7), 1,3,5,7-tetranitro- 1,3,5,7-tetrazacyclooctane with β-conformation (β-HMX) and N,N-dimethylformamide (DMF) in different molar ratios. The oxygen balance, density, detonation velocity, detonation pressure, and surface electrostatic potential were analyzed. The results indicate that the binding energies E b (*) and stabilities are in the order of 1:1 > 2:1 > 3:1 > 5:1 > 8:1 (CL-20:FOX-7/β-HMX/DMF). The values of E b (*) and stabilities of the energetic-nonenergetic CL-20/DMF cocrystals are far larger than those of the energetic-energetic CL-20/FOX-7 and CL-20/β-HMX, and those of CL-20/β-HMX are the smallest. For CL-20/FOX-7 and CL-20/β-HMX, the largest E b (*) appears in the cocrystals with the 1:1, 1:2 or 1:3 molar ratio, and the stabilities of the cocrystals with the excess ratio of CL-20 are weaker than those in the cocrystals with the excess ratio of FOX-7 or β-HMX. In CL-20/FOX-7, CL-20 prefers adopting the γ-form, and ε-CL-20 is the preference in CL-20/β-HMX, and ε-CL-20 and β-CL-20 can be found in CL-20/DMF. The CL-20/FOX-7 and CL-20/β-HMX cocrystals with low molar ratios can meet the requirements of low sensitive high energetic materials. Surface electrostatic potential reveals the nature of the sensitivity change upon the cocrystal formation. Graphical Abstract MD method was employed to study the binding energies on the selected crystal planes in the ε-, γ-, β-CL-20 cocrystals with FOX-7, β-HMX and DMF in different molar ratios. Surface electrostatic potential reveals the nature of the sensitivity change in cocrystals.

Expansion of the HMX-1 Flight Envelope With the EDU-5/P Laser Eye Protection Spectacles

National Research Council Canada - National Science Library

Penhallegon, William

2004-01-01

...) takeoffs and landings. Flight testing determined that fit, internal and external lighting conditions, aircrew experience, and aircrafi type are important factors in determining the suitability of the EDU-iIP in HMX-I plafforms...

Tracing the cycling and fate of the explosive 2,4,6-trinitrotoluene in coastal marine systems with a stable isotopic tracer, 15N-[TNT

Science.gov (United States)

Smith, Richard W.; Vlahos, Penny; Böhlke, John Karl; Ariyarathna, Thivanka; Ballentine, Mark; Cooper, Christopher; Fallis, Stephen; Groshens, Thomas J.; Tobias, Craig

2015-01-01

2,4,6-Trinitrotoluene (TNT) has been used as a military explosive for over a hundred years. Contamination concerns have arisen as a result of manufacturing and use on a large scale; however, despite decades of work addressing TNT contamination in the environment, its fate in marine ecosystems is not fully resolved. Here we examine the cycling and fate of TNT in the coastal marine systems by spiking a marine mesocosm containing seawater, sediments, and macrobiota with isotopically labeled TNT (15N-[TNT]), simultaneously monitoring removal, transformation, mineralization, sorption, and biological uptake over a period of 16 days. TNT degradation was rapid, and we observed accumulation of reduced transformation products dissolved in the water column and in pore waters, sorbed to sediments and suspended particulate matter (SPM), and in the tissues of macrobiota. Bulk δ15N analysis of sediments, SPM, and tissues revealed large quantities of 15N beyond that accounted for in identifiable derivatives. TNT-derived N was also found in the dissolved inorganic N (DIN) pool. Using multivariate statistical analysis and a 15N mass balance approach, we identify the major transformation pathways of TNT, including the deamination of reduced TNT derivatives, potentially promoted by sorption to SPM and oxic surface sediments.

An evaluation of the environmental fate and behavior of munitions materiel (tetryl and polar metabolites of TNT) in soil and plant systems. Preliminary evaluation of TNT-polar metabolites in plants

Energy Technology Data Exchange (ETDEWEB)

Fellows, R.J.; Harvey, S.D.; Cataldo, D.A.

1993-09-01

A preliminary study was conducted to elucidate the nature of the polar metabolites reported for plant tissues and xylem exudates following root accumulation of trinitrotoluene. Studies focused on the nature of the proposed conjugates of TNT-residues in xylem exudates of bush beam plants. Use of enzymatic methods failed to demonstrate that the conjugates were carbohydrate based, but acid hydrolysis indicated that the conjugates may be protein based. Of the five polar conjugates isolated from exudates, the presence of aminodinitrotoluene isomers and one unknown TNT residue was demonstrated.

Compatibility study of trans-1,4,5,8-tetranitro-1,4,5,8-tetraazadecalin (TNAD) with some energetic components and inert materials

International Nuclear Information System (INIS)

Yan Qilong; Li Xiaojiang; Zhang Laying; Li Jizhen; Li Hongli; Liu Ziru

2008-01-01

The compatibility of trans-1,4,5,8-tetranitro-1,4,5,8-tetraazadecalin (TNAD) with some energetic components and inert materials of solid propellants was studied by using the pressure DSC method where, cyclotetramethylenetetranitroamine (HMX), cyclotrimethylenetrinitramine (RDX), 1,4-dinitropiperazine (DNP), 1.25/1-NC/NG mixture, lead 3-nitro-1,2,4-triazol-5-onate (NTO-Pb), aluminum powder (Al, particle size = 13.6 μm) and N-nitrodihydroxyethylaminedinitrate (DINA) were used as energetic components and polyethylene glycol (PEG), polyoxytetramethylene-co-oxyethylene (PET), addition product of hexamethylene diisocyanate and water (N-100), 2-nitrodianiline (2-NDPA), 1,3-dimethyl-1,3-diphenyl urea (C 2 ), carbon black (C.B.), aluminum oxide (Al 2 O 3 ), cupric 2,4-dihydroxy-benzoate (β-Cu), cupric adipate (AD-Cu) and lead phthalate (φ-Pb) were used as inert materials. It was concluded that the binary systems of TNAD with NTO-Pb, RDX, PET and Al powder are compatible, and systems of TNAD with DINA and HMX are slightly sensitive, and with 2-NDPA, φ-Pb, β-Cu, AD-Cu and Al 2 O 3 are sensitive, and with PEG, N-100, C 2 and C.B. are incompatible. The impact and friction sensitivity data of the TNAD and TNAD in combination with the other energetic materials under present study was also obtained, and there was no consequential affiliation between sensitivity and compatibility

Fabrication of L-cysteine-capped CdTe quantum dots based ratiometric fluorescence nanosensor for onsite visual determination of trace TNT explosive

Energy Technology Data Exchange (ETDEWEB)

Qian, Jing; Hua, Mengjuan [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013 (China); Wang, Chengquan [Changzhou College of Information Technology, Changzhou 213164 (China); Wang, Kan; Liu, Qian; Hao, Nan [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013 (China); Wang, Kun, E-mail: wangkun@ujs.edu.cn [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013 (China)

2016-11-23

New strategies for onsite determination of trace 2,4,6-trinitrotoluene (TNT) explosives have become a research hotspot for homeland security needs against terrorism and environmental concerns. Herein, we designed a ratiometric fluorescence nanohybrid comprising 3-mercaptopropionic acid-capped green-emitting CdTe quantum dots (gQDs) encapsulated into SiO{sub 2} sphere and L-cysteine (Lcys)-capped red-emitting CdTe QDs (rQDs) conjugated onto SiO{sub 2} surface. The surface Lcys can be used as not only the stabilizer of the rQDs but also the primary amine provider which can react with TNT to form Meisenheimer complexes. Without any additional surface modification procedure, the fluorescence of rQDs equipped with Lcys was selectively quenched by TNT because electrons of the rQDs transferred to TNT molecules due to the formation of Meisenheimer complexes. Meanwhile, the embedded gQDs always remained constant. Upon exposure to increasing amounts of TNT, the fluorescence of rQDs could be gradually quenched and consequently the logarithm of the dual emission intensity ratios exhibited a good linear negative correlation with TNT concentration over a range of 10 nM–8 μM with a low detection limit of 3.3 nM. One can perform onsite visual determination of TNT with high resolution because the ratiometric fluorescence nanosensing system exhibited obvious fluorescence color changes. This sensing strategy has been successfully applied in real samples and already integrated in a filter paper-based assay, which enables potential fields use application featuring easy handling and cost-effectiveness. - Highlights: • A facile strategy for preparing Lcys-capped rQDs based hybrid spheres was reported. • Lcys serves as the stabilizer of rQDs and primary amine provider to react with TNT. • One can perform onsite visual determination of TNT by using such probe. • The nanosensor exhibited a wide linear range and a low detection limit. • This sensing strategy can be fully

Combustion Mechanisms of Very High Burn Rate (VHBR) Propellant. Phase II.

Science.gov (United States)

1995-09-01

potassium salt of B10H1 2-. The Kraton slate and the Hycar slate both contain RDX as the oxidizer, while the PEG slate contains HMX and TAGN in the... polyacrylate (Hycar), hydroxy-terminated polybutadiene, and a mixture of styrene and ethylene-butylene (Kraton). As might be expected, when all else is equal...proprietary formulations of Teledyne-McCormick-Selph (TMS), designated H498 and H466. In H498, a potassium cation is utilized, while in H466, an

Small Scale Characterization of the Presence of the Explosive Octahydro-1,3,5,7-tetranitro- 1,3,5,7 tetrazocine (HMX) Near Former Naval Sites on Vieques Island, Puerto Rico

Science.gov (United States)

Simmons, C. C.; Carvalho-Knighton, K. M.; Pyrtle, A. J.

2007-12-01

Octahydro-1,3,5,7-tetranitro-1,3,5,7 tetrazocine (HMX) is a synthetic energetic compounds that has been commonly used in military munitions. The presence and movement of HMX through the environment is of growing concern because of potential civilian exposure and impacts on human health. HMX remains in the environment unreactive with little degradation. It can be transported great distances in water thus having the possibility for migrating into groundwater. The former naval sites in Vieques were used for weapons training and housed several disposal sites. Previous studies around these sites indicate the presence of radioactive materials produced through thermal fission, such as Cs-137. Since HMX was primarily used to implode fissionable materials in nuclear devices, evaluating the release of HMX and consequent movement through the environment at these sites is essential. Surface water and soil samples as well as core and pore water samples were collected from two sites in Vieques; Kiani Lagoon and Mosquito Bay. All samples were extracted using EPA method 8330 and analyzed using RP-HPLC analysis with a C-18 column. HMX was undetected in samples collected from both Kiani Lagoon and Mosquito Bay. The development of a model that studies the flow rates and fate of water runoff in these areas of interest, coupled with data on groundwater testing inside the actual former naval facilities, is being explored for further sample collection and analysis.

Validation of Passive Sampling Devices for Monitoring of Munitions Constituents in Underwater Environments

Science.gov (United States)

2017-09-01

and sampling handling was met. All calibration criteria and instrument maintenance was met for all final reported data. 23 3.2 QUALITATIVE ...the relatively large size of each sampling box within the grid, there were no issues associated with locating appropriate anchoring locations, based...quantiative, as only estimated sampling rates were available, or spiked recoveries were lower suggesting the results are qualitative . TNT RDX ADNTs

Thermal Decomposition Behaviors and Burning Characteristics of AN/RDX-Based Composite Propellants Supplemented with MnO2 and Fe2O3

Science.gov (United States)

Kohga, Makoto; Naya, Tomoki

2015-10-01

Ammonium nitrate (AN)-based composite propellants have gained popularity because of the clean burning nature of AN as an oxidizer. However, such propellants have several disadvantages such as poor ignition and low burning rate. The burning characteristics of the AN propellant were improved when a portion of this propellant was replaced by an energetic material and the addition of a catalyst. In this study, RDX (1,3,5-trinitroperhydro-1,3,5-triazine) was used as the energetic material, and Fe2O3 and MnO2 were used as catalysts. The burning characteristics of the AN/RDX propellants supplemented with catalysts were investigated, and the effects of the replacement of AN by RDX and the catalyst addition were evaluated.

RDX in Plant Tissue: Leading to Humification in Surface Soils

Science.gov (United States)

2013-01-01

distribution, and transfor- mation of TNT in higher plants. Ecotoxicology and Environmental Safety 64(2): 136–145. Amann, R. I., W. Ludwig, and K.-H...Schleifer. 1995. Phyolgenetic identification and in situ detection of individual microbial cells without cultivation . Microbiol. Rev. 59: 143–169

Pathways for the radioactive synthesis of metabolites of TNT

International Nuclear Information System (INIS)

Shimoni, M.; Blitzblau, M.; Cohen, A.; Cohen, H.; Hagag, Y.; Buchman, U.

1982-02-01

The following two metabolites of TNT were prepared: 2,4-dinitro-6-aminotoluene and 2,4-dinitro-4-aminotoluene. The first was prepared by ''cold'' microsynthesis and not by ''hot'' one because of technical problems. The second was synthesized by a ''hot'' synthesis as well. The resulting specific activity was 4.26 Ci/mmol. (Author)

The value of T/NT in FDG imaging with a coincidence camera for diagnosis of pulmonary nodules and mass lesions

International Nuclear Information System (INIS)

Sun Da; Zhan Hongwei; Xu Wei; Ye Xiaojuan; Liu Qichang

2004-01-01

Objectives: To assess the value of T/NT in FDG imaging with a coincidence camera for diagnosis of pulmonary nodules and mass lesions. Methods: 18F-FDG imaging were performed in 57 patients with a mean age of 62.18 (range from 33 83 years old) for diagnosis of pulmonary nodules and mass lesions using a gamma camera with 1 inch crystal in coincidence mode (Siemens E.comduet). 175 296 MBq (5 8 mci) of 18F-FDG was given by iv on an empty stomach at least for 6 hours, and a whole body imaging without brain and legs was performed after 40 60 minutes. The count rate of target ROI and no-target ROI (T/NT) were calculated as a semiquantative analysis to differentiate malignant from inflammatory lesions. The result was compared with CT, MRI, and/or pathology. Results: The mean value of T/NT in malignant lesions (N=45) in lungs is 4.32 (range 1.61 10.62). But it is 1.52 (range 1.37 1.95) in inflammatory lesions (N=17) in lungs, and 4.09 (range 2.2 7.01) in lung tuberculosis lesions (N=5). In 45 malignant, the value of T/NT is less than 2.0 in only 3 lesions. So the overlapping of T/NT value is very little between malignant and inflammatory lesions. But there is full overlapping of T/NT value between malignant and tuberculosis lesions. Conclusions: Focal pulmonary nodules and mass lesions are commonly encountered in clinical practice, and PET with 18F-FDG has proved to be an accurate noninvasive test for identifying pulmonary malignant lesions. The technique of semiquantity with T/NT is useful to differentiate malignant from inflammatory lesions. But it is invalidate for distinguishing malignant from tuberculosis lesions. (authors)

Development Of An In Situ Passive Sampler For The Detection And Remediation of Explosive Compounds

Science.gov (United States)

2016-06-07

including high performance liquid chromatography (HPLC), gas chromatography mass spectrometry (GCMS) and isotope ratio mass spectrometry ( IRMS ) as...GCMS) and isotope ratio mass spectrometry ( IRMS ) as summarized in St. George et al., 2010 and Smith et al., 2013, 2014. Depuration rates will be...TNT and RDX for the depuration compounds and unlabeled compounds in the ambient environment. These will be quantified as above by GCMS and IRMS . 2015

FY90 R&D Project Descriptions ESL (Engineering & Services Laboratory) Environics Division

Science.gov (United States)

1989-07-01

nutrient demand and potential adverse reactions. Alternatives to ammonlum chloride and sodium phosphate nutrient formulas may reduce adverse side...RDX1, 2,4,6-trinltrotoluene [TNT], and l,l-dimethylhydrazine [ UDMH ]) will be dissolved or slurried in water or dissolved in an organic solvent. The...which will include measurement of NOx in the feed to the reactor and in the exhaust. Variables will include the temperature and particulate density of

Transformation of TNT to Triaminotoluene by Mixed Cultures Incubated Under Methanogenic Conditions

National Research Council Canada - National Science Library

Hwang, Philip

1998-01-01

...), and demilitarization operations. Granular activated carbon adsorption is the standard technology for treating wastewater containing TNT and maintaining discharges within the limits established under the National Pollutant Discharge Elimination System...

Transformation and fate of 2,4,6-trinitrotoluene (TNT) in anaerobic bioslurry reactors under various aeration schemes: implications for the decontamination of soils.

Science.gov (United States)

Newcombe, David A; Crawford, Ronald L

2007-12-01

Energetic compounds have been used in a variety of industrial and military applications worldwide leading to widespread environmental contamination. Many of these compounds are toxic and resist degradation by oxidative enzymes resulting in a need for alternative remediation methods. It has been shown that trinitrotoluene (TNT)-contaminated soil subjected to treatment in strictly anaerobic bioreactors results in tight binding of TNT transformation products to soil organic matter. The research presented here examined the fate of TNT and its metabolites in bioreactors under three different aeration regimes. In all treatment regimes, the typical metabolites of aminodinitrotoluenes and diaminonitrotoluenes were observed prior to irreversible binding into the soil fraction of the slurry. Significant transformation of TNT into organic acids or simple diols, as others report in prior work, was not observed in any of the treatments and is an unlikely fate of TNT in anaerobic soil slurries. These results indicate that aeration does not dramatically affect transformation or fate of TNT in reactor systems that receive a rich carbon source but does affect the rate at which metabolites become tightly bound to the soil. The most rapid transformations and lowest redox potentials were observed in reactors in which an aerobic headspace was maintained suggesting that aerobes play a role in establishing conditions that are most conducive to TNT reduction.

New perspectives in the PAW/GIPAW approach: J(P-O-Si) coupling constants, antisymmetric parts of shift tensors and NQR predictions.

Science.gov (United States)

Bonhomme, Christian; Gervais, Christel; Coelho, Cristina; Pourpoint, Frédérique; Azaïs, Thierry; Bonhomme-Coury, Laure; Babonneau, Florence; Jacob, Guy; Ferrari, Maude; Canet, Daniel; Yates, Jonathan R; Pickard, Chris J; Joyce, Siân A; Mauri, Francesco; Massiot, Dominique

2010-12-01

In 2001, Pickard and Mauri implemented the gauge including projected augmented wave (GIPAW) protocol for first-principles calculations of NMR parameters using periodic boundary conditions (chemical shift anisotropy and electric field gradient tensors). In this paper, three potentially interesting perspectives in connection with PAW/GIPAW in solid-state NMR and pure nuclear quadrupole resonance (NQR) are presented: (i) the calculation of J coupling tensors in inorganic solids; (ii) the calculation of the antisymmetric part of chemical shift tensors and (iii) the prediction of (14)N and (35)Cl pure NQR resonances including dynamics. We believe that these topics should open new insights in the combination of GIPAW, NMR/NQR crystallography, temperature effects and dynamics. Points (i), (ii) and (iii) will be illustrated by selected examples: (i) chemical shift tensors and heteronuclear (2)J(P-O-Si) coupling constants in the case of silicophosphates and calcium phosphates [Si(5)O(PO(4))(6), SiP(2)O(7) polymorphs and α-Ca(PO(3))(2)]; (ii) antisymmetric chemical shift tensors in cyclopropene derivatives, C(3)X(4) (X = H, Cl, F) and (iii) (14)N and (35)Cl NQR predictions in the case of RDX (C(3)H(6)N(6)O(6)), β-HMX (C(4)H(8)N(8)O(8)), α-NTO (C(2)H(2)N(4)O(3)) and AlOPCl(6). RDX, β-HMX and α-NTO are explosive compounds. Copyright © 2010 John Wiley & Sons, Ltd.

Label-free peptide aptamer based impedimetric biosensor for highly sensitive detection of TNT with a ternary assembly layer.

Science.gov (United States)

Li, Yanyan; Zhao, Manru; Wang, Haiyan

2017-11-01

We report a label-free peptide aptamer based biosensor for highly sensitive detection of TNT which was designed with a ternary assembly layer consisting of anti-TNT peptide aptamer (peptamer), dithiothreitol (DTT), and 6-mercaptohexanol (MCH), forming Au/peptamer-DTT/MCH. A linear relationship between the change in electron transfer resistance and the logarithm of the TNT concentration from 0.44 to 18.92 pM, with a detection limit of 0.15 pM, was obtained. In comparison, the detection limit of the aptasensor with a common binary assembly layer (Au/peptamer/MCH) was 0.15 nM. The remarkable improvement in the detection limit could be ascribed to the crucial role of the ternary assembly layer, providing an OH-richer hydrophilic environment and a highly compact surface layer with minimal surface defects, reducing the non-covalent binding (physisorption) of the peptamer and non-specific adsorption of TNT onto the electrode surface, leading to high sensitivity, and which can serve as a general sensing platform for the fabrication of other biosensors.

Delayed myelosuppression with acute exposure to hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and environmental degradation product hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) in rats

Energy Technology Data Exchange (ETDEWEB)

Jaligama, Sridhar; Kale, Vijay M.; Wilbanks, Mitchell S. [Department of Toxicology, College of Pharmacy, University of Louisiana at Monroe, Monroe, LA 71209 (United States); Perkins, Edward J. [US Army Engineer Research and Development Center, Vicksburg, MS 39180 (United States); Meyer, Sharon A., E-mail: meyer@ulm.edu [Department of Toxicology, College of Pharmacy, University of Louisiana at Monroe, Monroe, LA 71209 (United States)

2013-02-01

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), a widely used munitions compound, and hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX), its N-nitroso product of anaerobic microbial nitroreduction, are contaminants of military sites. Previous studies have shown MNX to be the most acutely toxic among the nitroreduced degradation products of RDX and to cause mild anemia at high dose. The present study compares hematotoxicity with acute oral exposure to MNX with parent RDX. Both RDX and MNX caused a modest decrease in blood hemoglobin and ∼ 50% loss of granulocytes (NOAELs = 47 mg/kg) in female Sprague–Dawley rats observed 14 days post-exposure. We explored the possibility that blood cell loss observed after 14 days was delayed in onset because of toxicity to bone marrow (BM) progenitors. RDX and MNX decreased granulocyte/macrophage-colony forming cells (GM-CFCs) at 14, but not 7, days (NOAELs = 24 mg/kg). The earliest observed time at which MNX decreased GM-CFCs was 10 days post-exposure. RDX and MNX likewise decreased BM burst-forming units-erythroid (BFU-Es) at 14, but not 7, days. Granulocyte–erythrocyte–monocyte–megakaryocyte (GEMM)-CFCs were unaffected by RDX and MNX at 7 days suggesting precursor depletion did not account for GM-CFC and BFU-E loss. MNX added to the culture media was without effect on GM-CFC formation indicating no direct inhibition. Flow cytometry showed no differential loss of BM multilineage progenitors (Thy1.1{sup +}) or erythroid (CD71{sup +}) precursors with MNX suggesting myeloid and erythroid lineages were comparably affected. Collectively, these data indicate that acute exposure to both RDX and MNX caused delayed suppression of myelo- and erythropoiesis with subsequent decrease of peripheral granulocytes and erythrocytes. Highlights: ► Acute oral exposure to munitions RDX causes myelosuppression. ► Environmental degradation product MNX is comparable in effect. ► RDX and MNX are cytotoxic to both myeloid and erythroid

Modeling compaction-induced energy dissipation of granular HMX

Energy Technology Data Exchange (ETDEWEB)

Gonthier, K.A. [Lamar Univ., Beaumont, TX (US). Dept. of Mechanical Engineering; Menikoff, R.; Son, S.F.; Asay, B.W. [Los Alamos National Lab., NM (US)

1998-12-31

A thermodynamically consistent model is developed for the compaction of granular solids. The model is an extension of the single phase limit of two-phase continuum models used to describe Deflagration-to-Detonation Transition (DDT) experiments. The focus is on the energetics and dissipation of the compaction process. Changes in volume fraction are partitioned into reversible and irreversible components. Unlike conventional DDT models, the model is applicable from the quasi-static to dynamic compaction regimes for elastic, plastic, or brittle materials. When applied to the compaction of granular HMX (a brittle material), the model predicts results commensurate with experiments including stress relaxation, hysteresis, and energy dissipation. The model provides a suitable starting point for the development of thermal energy localization sub-scale models based on compaction-induced dissipation.

Field detection capability of immunochemical assays during criminal investigations involving the use of TNT.

Science.gov (United States)

Romolo, Francesco Saverio; Ferri, Elida; Mirasoli, Mara; D'Elia, Marcello; Ripani, Luigi; Peluso, Giuseppe; Risoluti, Roberta; Maiolini, Elisabetta; Girotti, Stefano

2015-01-01

The capability to collect timely information about the substances employed on-site at a crime scene is of fundamental importance during scientific investigations in crimes involving the use of explosives. TNT (2,4,6-trinitrotoluene) is one of the most employed explosives in the 20th century. Despite the growing use of improvised explosives, criminal use and access to TNT is not expected to decrease. Immunoassays are simple and selective analytical tests able to detect molecules and their immunoreactions can occur in portable formats for use on-site. This work demonstrates the application of three immunochemical assays capable of detecting TNT to typical forensic samples from experimental tests: an indirect competitive ELISA with chemiluminescent detection (CL-ELISA), a colorimetric lateral flow immunoassay (LFIA) based on colloidal gold nanoparticles label, and a chemiluminescent-LFIA (CL-LFIA). Under optimised working conditions, the LOD of the colorimetric LFIA and CL-LFIA were 1 μg mL(-1) and 0.05 μg mL(-1), respectively. The total analysis time for LFIAs was 15 min. ELISA proved to be a very effective laboratory approach, showing very good sensitivity (LOD of 0.4 ng mL(-1)) and good reproducibility (CV value about 7%). Samples tested included various materials involved in controlled explosions of improvised explosive devices (IEDs), as well as hand swabs collected after TNT handling tests. In the first group of tests, targets covered with six different materials (metal, plastic, cardboard, carpet fabric, wood and adhesive tape) were fixed on top of wooden poles (180 cm high). Samples of soil from the explosion area and different materials covering the targets were collected after each explosion and analysed. In the second group of tests, hand swabs were collected with and without hand washing after volunteers simulated the manipulation of small charges of TNT. The small amount of solution required for each assay allows for several analyses. Results of

Ignition and Growth Modeling of Detonating LX-04 (85% HMX / 15% VITON) Using New and Previously Obtained Experimental Data

Science.gov (United States)

Tarver, Craig

2017-06-01

An Ignition and Growth reactive flow model for detonating LX-04 (85% HMX / 15% Viton) was developed using new and previously obtained experimental data on: cylinder test expansion; wave curvature; failure diameter; and laser interferometric copper and tantalum foil free surface velocities and LiF interface particle velocity histories. A reaction product JWL EOS generated by the CHEETAH code compared favorably with the existing, well normalized LX-04 product JWL when both were used with the Ignition and Growth model. Good agreement with all existing experimental data was obtained. Keywords: LX-04, HMX, detonation, Ignition and Growth PACS:82.33.Vx, 82.40.Fp This work was performed under the auspices of the U. S. Department of Energy by the Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344.

Multipurpose Sediment Passive Sampler with Improved Tissue Mimicry to Measure the Bioavailable Fraction

Science.gov (United States)

2016-11-01

run by HPLC- DAD . There was a linear relationship between the RDX found in the extract and the amount in the solution (Figures 11 and 12, Raw data can...TNT had occurred in the reaction solution. Moreover, the anion is reactive and can form Meisenheimer complexes with electron rich compounds...The poor recovery was determined to be due to the desorption step since it was found that the samplers efficiently extracted the metals from solution

Non-equilibrium dynamics due to moving deflagration front at RDX/HTPB interface

Science.gov (United States)

Chaudhuri, Santanu; Joshi, Kaushik; Lacevic, Naida

Reactive dissipative particle dynamics (DPD-RX), a promising tool in characterizing the sensitivity and performance of heterogeneous solid propellants like polymer bonded explosives (PSXs), requires further testing for non-equilibrium dynamics. It is important to understand detailed atomistic chemistry for developing coarse grain reactive models needed for the DPD-RX. In order to obtain insights into combustion chemistry of RDX/HTPB binder, we used reactive molecular dynamics (RMD) to obtain energy up-pumping and reaction mechanisms at RDX/HTPB interface when exposed to a self-sustaining deflagration front. Hot spots are ignited near and away from the heterogeneous interface using the thermal pulse. The results show that the hot spot near interface significantly delays the transition from ignition to deflagration. We will present the mechanical response and the combustion chemistry of HTPB when the propagating deflagration front hits the polymer binder. We will discuss our efforts to incorporate this RMD based chemistry into the DPD-RX which will enable us to perform such non-equilibrium dynamics simulations on large-length scale with microstructural heterogeneities. Funding from DTRA Grant Number HDTRA1-15-1-0034 is acknowledged.

Cost and Performance Report: Bioaugmentation for Aerobic Bioremediation of RDX-Contaminated Groundwater

Science.gov (United States)

2015-09-01

costs were also included. The addition of two extraction wells would not require an upgrade of the current granular activated carbon (GAC) treatment...transport properties, and RDX-degrading activity in UMCD aquifer material and groundwater. Phase II included a field-scale cell transport test conducted ...Accordingly, users may plan to conduct a field tracer test to confirm hydraulic connectivity between the injection and downgradient monitoring

The tolerance efficiency of Panicum maximum and Helianthus annuus in TNT-contaminated soil and nZVI-contaminated soil.

Science.gov (United States)

Jiamjitrpanich, Waraporn; Parkpian, Preeda; Polprasert, Chongrak; Laurent, François; Kosanlavit, Rachain

2012-01-01

This study was designed to compare the initial method for phytoremediation involving germination and transplantation. The study was also to determine the tolerance efficiency of Panicum maximum (Purple guinea grass) and Helianthus annuus (Sunflower) in TNT-contaminated soil and nZVI-contaminated soil. It was found that the transplantation of Panicum maximum and Helianthus annuus was more suitable than germination as the initiate method of nano-phytoremediation potting test. The study also showed that Panicum maximum was more tolerance than Helianthus annuus in TNT and nZVI-contaminated soil. Therefore, Panicum maximum in the transplantation method should be selected as a hyperaccumulated plant for nano-phytoremediation potting tests. Maximum tolerance dosage of Panicum maximum to TNT-concentration soil was 320 mg/kg and nZVI-contaminated soil was 1000 mg/kg in the transplantation method.

Energetic Di- and Trinitromethylpyridines: Synthesis and Characterization

Directory of Open Access Journals (Sweden)

Yiying Zhang

2017-12-01

Full Text Available Pyridine derivatives based on the addition of trinitromethyl functional groups were synthesized by the reaction of N2O4 with the corresponding pyridinecarboxaldoximes, then they were converted into dinitromethylide hydrazinium salts. These energetic compounds were fully characterized by IR and NMR spectroscopy, elemental analysis, differential scanning calorimetry (DSC, and X-ray crystallography. These pyridine derivatives have good densities, positive enthalpies of formation, and acceptable sensitivity values. Theoretical calculations carried out using Gaussian 03 and EXPLO5 programs demonstrated good to excellent detonation velocities and pressures. Each of these compounds is superior in performance to TNT, while 2,6-bis(trinitromethylpyridine (D = 8700 m·s−1, P = 33.2 GPa shows comparable detonation performance to that of RDX, but its thermal stability is too low, making it inferior to RDX.

Long-Wave Infrared (LWIR) Molecular Laser-Induced Breakdown Spectroscopy (LIBS) Emissions of Thin Solid Explosive Powder Films Deposited on Aluminum Substrates.

Science.gov (United States)

Yang, Clayton S-C; Jin, Feng; Trivedi, Sudhir B; Brown, Ei E; Hommerich, Uwe; Tripathi, Ashish; Samuels, Alan C

2017-04-01

Thin solid films made of high nitro (NO 2 )/nitrate (NO 3 ) content explosives were deposited on sand-blasted aluminum substrates and then studied using a mercury-cadmium-telluride (MCT) linear array detection system that is capable of rapidly capturing a broad spectrum of atomic and molecular laser-induced breakdown spectroscopy (LIBS) emissions in the long-wave infrared region (LWIR; ∼5.6-10 µm). Despite the similarities of their chemical compositions and structures, thin films of three commonly used explosives (RDX, HMX, and PETN) studied in this work can be rapidly identified in the ambient air by their molecular LIBS emission signatures in the LWIR region. A preliminary assessment of the detection limit for a thin film of RDX on aluminum appears to be much lower than 60 µg/cm 2 . This LWIR LIBS setup is capable of rapidly probing and charactering samples without the need for elaborate sample preparation and also offers the possibility of a simultaneous ultraviolet visible and LWIR LIBS measurement.

Retrotransposons of the Tnt1B family are mobile in Nicotiana plumbaginifolia and can induce alternative splicing of the host gene upon insertion.

Science.gov (United States)

Leprinc, A S; Grandbastien, M A; Christian, M

2001-11-01

Active retrotransposons have been identified in Nicotiana plumbaginifolia by their ability to disrupt the nitrate reductase gene in chlorate-resistant mutants selected from protoplast-derived cultures. In mutants E23 and F97, two independent insertions of Tnp2, a new retrotransposon closely related to the tobacco Tnt1 elements, were detected in the nitrate reductase gene. These two Tnp2 elements are members of the Tnt1B subfamily which shows that Tnt1B elements can be active and mutagenic in the N. plumbaginifolia genome. Furthermore, these results suggest that Tnt1B is the most active family of Tntl elements in N. plumbaginifolia, whereas in tobacco only members of the Tnt1A subfamily were found inserted in the nitrate reductase gene. The transcriptional regulations of Tnp2 and Tnt1A elements are most probably different due to non-conserved U3 regions. Our results thus support the hypothesis that different Nicotiana species contain different active Tntl subfamilies and that only one active Tntl subfamily might be maintained in each of these species. The Tnp2 insertion found in the F97 mutant was found to be spliced out of the nitrate reductase mRNA by activation of cryptic donor and acceptor sites in the nitrate reductase and the Tnp2 sequences respectively.

TNT Degradation by Natural Microbial Assemblages at Frontal Boundaries Between Water Masses in Coastal Ecosystems (ER-2124 Interim Report)

Science.gov (United States)

2014-06-26

Tuominen, L. 1995. Comparison of leucine uptake methods and a thymidine incorporation method for measuring bacterial activity in sediment. J...measuring TNT incorporation rates into bacterial DNA using sediment samples. By seasonally repeating these survey measurements and mixing experiments...of days to months (e.g., PAHs; Boyd et al. 2008). TNT ring carbon is incorporated into bacterial macromolecules at rates in water that are 10-100

Combined zero-valent iron and fenton processes for the treatment of Brazilian TNT industry wastewater

International Nuclear Information System (INIS)

Barreto-Rodrigues, Marcio; Silva, Flavio T.; Paiva, Teresa C.B.

2009-01-01

The environmental impact caused by the production of explosives made from nitroaromatic compounds such as 2,4,6-trinitrotoluene (TNT) is currently a major concern, mainly due to their toxic nature, a fact that makes these compounds highly harmful. This work evaluated a continual system treatment reactor (CSTR) consisting of column zero-valent iron and a system to promote a fenton reaction in order to create possible definitive routines for treating effluents originating from the TNT production process. The spectrophotometric results demonstrated that this combination of processes was highly efficient in promoting the removal of all the absorbed species at 290 nm and the visible region of the specter. The results also revealed that the combination of treatments was significantly efficient in terms of correcting the effluent's main parameters of relevance, mainly COD (95.5% reduction) and TNT concentration, whose total was converted into nitrous and phenolic compounds and, additionally, the acute toxicity was also significantly reduced (95%). These results indicate that the strategy can serve as an efficient option for effluent treatment, for release into the receiving body, or eventually for use as industrial reuse water.

Near infrared optical biosensor based on peptide functionalized single-walled carbon nanotubes hybrids for 2,4,6-trinitrotoluene (TNT) explosive detection.

Science.gov (United States)

Wang, Jin

2018-06-01

A near infrared (NIR) optical biosensor based on peptide functionalized single-walled carbon nanotubes (SWCNTs) hybrids for 2,4,6-trinitrotoluene (TNT) explosive detection was developed. The TNT binding peptide was directly anchored on the sidewall of the SWCNTs using the π-π interaction between the aromatic amino acids and SWCNTs, forming the peptide-SWCNTs hybrids for near infrared absorption spectra measurement. The evidence of the morphology of peptide-SWCNTs hybrids was obtained using atomic force microscopy (AFM). The results demonstrated that peptide-SWCNTs hybrids based NIR optical biosensor exhibited sensitive and highly selective for TNT explosive determination, addressing a promising optical biosensor for security application. Copyright © 2018. Published by Elsevier Inc.

Graphene-based electrochemical sensor for detection of 2,4,6-trinitrotoluene (TNT) in seawater: the comparison of single-, few-, and multilayer graphene nanoribbons and graphite microparticles.

Science.gov (United States)

Goh, Madeline Shuhua; Pumera, Martin

2011-01-01

The detection of explosives in seawater is of great interest. We compared response single-, few-, and multilayer graphene nanoribbons and graphite microparticle-based electrodes toward the electrochemical reduction of 2,4,6-trinitrotoluene (TNT). We optimized parameters such as accumulation time, accumulation potential, and pH. We found that few-layer graphene exhibits about 20% enhanced signal for TNT after accumulation when compared to multilayer graphene nanoribbons. However, graphite microparticle-modified electrode provides higher sensitivity, and there was no significant difference in the performance of single-, few-, and multilayer graphene nanoribbons and graphite microparticles for the electrochemical detection of TNT. We established the limit of detection of TNT in untreated seawater at 1 μg/mL.

IRIS Toxicological Review of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (RDX) (Public Comment Draft)

Science.gov (United States)

EPA is developing an Integrated Risk Information System (IRIS) assessment of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and has released the draft assessment for public comment. When final, the assessment will appear on the IRIS database.

TNT Biodegradation by Natural Microbial Assemblages at Estuarine Frontal Boundaries

Science.gov (United States)

2012-07-02

St- Jean . 2007. The use of wet chemical oxidation with high-amplification isotope ratio mass spectrometry (WCO-IRMS) to measure stable isotope ...dissolved oxygen concentration (DO, mL L-1), bacterial production and mineralization rate of TNT, naphthalene (NAH) and phenanthrene (PHE) (water...m) in the Charleston Harbor system (26 June 2011) and measured for salinity (PSU), temperature (oC), dissolved oxygen concentration (DO, mL L-1

Phytoremediation of soil co-contaminated with heavy metals and TNT using four plant species.

Science.gov (United States)

Lee, Insook; Baek, Kyunghwa; Kim, Hyunhee; Kim, Sunghyun; Kim, Jaisoo; Kwon, Youngseok; Chang, Yoontoung; Bae, Bumhan

2007-11-01

We investigated the germination, growth rates and uptake of contaminants of four plant species, barnyard grass (Echinochloa crusgalli), sunflower (Helianthus annuus), Indian mallow (Abutilon avicennae) and Indian jointvetch (Aeschynomene indica), grown in soil contaminated with cadmium (Cd), lead (Pb) and 2,4,6-trinitrotoluene (TNT). These contaminants are typically found at shooting ranges. Experiments were carried out over 180 days using both single plant cultures and cultures containing an equal mix of the 4 plant species. Germination rates differed among the species in single culture (92% for H. annuus, 84% for E. crusgalli, 48% for A. avicennae and 38% Ae. indica). In the 4-plant mix culture, phytoremediation for the removal of heavy metals and TNT from contaminated soils should use a single plant species rather than a mixture of several plants.

IRIS Toxicological Review of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (RDX) (Preliminary Assessment Materials)

Science.gov (United States)

In August 2013, EPA released the draft literature searches and associated search strategies, evidence tables, and exposure response arrays for RDX to obtain input from stakeholders and the public prior to developing the draft IRIS assessment. Specifically, EPA was interested in c...

Fizičko-hemijske i detonacione karakteristike nitraminskih eksploziva - RDX, HMX i CL-20 / Physico-chemical and detonation properties of nitramine explosives: RDX, HMX and CL-20

Directory of Open Access Journals (Sweden)

Mirjana Anđelković-Lukić

2002-11-01

Full Text Available U radu su prikazane fizičko-hemijske i detonacione karakteristike nitraminskih brizantnih eksploziva, heksogena i oktogena, uporedene sa osobinama novog cikličnog nitraminskog eksploziva CL-20. Novi visokobrizantni eksploziv CL-20 postoji u četiri kristalne forme, stabilne na različitim temepraturama. Ima bolje detonacione karakteristike od heksogena i oktogena veću gustinu i brzinu detonacije, all mnogo veću osetljivost na udar i trenje, reda PETN. Zbog toga se ovaj eksploziv flegmatizuje sa polimerima etilenvinilacetatom (EVA i estanom. Da bi se povećale energetske performanse eksploziva i smanjila osetljivost na mehanička dejstva eksplozivu CL-20 dodaju se visokoenergetski materijali, fluoronitrojedinjenja (FEFO. / In this paper the physico-chemical and detonation properties of nitramine high explosives, hexogen and octogen, are presented and compared with a polycyclic nitramine high explosive CL-20. This new high explosive CL-20 exists in four crystalline forms, stable at different temperatures. CL-20 has better detonation properties than hexogen and octogen, higher density and detonation rate, but greater impact and friction sensitivity (of PETN class. So it is necessary to bond this explosive with polymers-ethylenvinil acetat (EVA and estane to reduce sensitivity to mechanical effects. CL-20 can be prepared by adding high energy materials-fluoro-nitro compounds (FEFO as regulators of energy performances.

I-TNT: PHONE NUMBER EXPANSION AND TRANSLATION SYSTEM FOR MANAGING INTERCONNECTIVITY ADDRESSING IN SIP PEERING

Directory of Open Access Journals (Sweden)

A. A. KHUDHER

2015-02-01

Full Text Available Voice over IP (VoIP subscribers is growing vastly in the recent years due to the ever increase in smartphones, 3G, WiFi, etc. This growth leads the VoIP service providers to peer with each other through Session Initiation Protocol (SIP peering for low/free cost of voice communication. Naturally, this growth is not without challenges, especially in phone addressing. This paper proposes an I-TNT (Infrastructure-Phone Number Translation numbering system to expand the range of the existing E.164 numbers and mapping between private and public number at the edge of the signalling path. As a result, I-TNT numbering system is successfully implemented and able to allocate the expanded phone numbers to end-users in one service provider.

Deflagration to detonation experiments in granular HMX

Energy Technology Data Exchange (ETDEWEB)

Burnside, N.J.; Son, S.F.; Asay, B.W.; Dickson, P.M.

1998-03-01

In this paper the authors report on continuing work involving a series of deflagration-to-detonation transition (DDT) experiments in which they study the piston-initiated DDT of heavily confined granular cyclotetramethylenetetranitramine (HMX). These experiments were designed to he useful in model development and evaluation. A main focus of these experiments is the effect of density on the DDT event. Particle size distribution and morphology are carefully characterized. In this paper they present recent surface area analysis. Earlier studies demonstrated extensive fracturing and agglomeration in samples at densities as low as 75% TMD as evidenced by dramatic decreases in particle size distribution due to mild stimulus. This is qualitatively confirmed with SEM images and quantitatively studied with gas absorption surface area analysis. Also, in this paper they present initial results using a microwave interferometer technique. Dynamic calibration of the technique was performed, a 35 GHz signal is used to increase resolution, and the system has been designed to be inexpensive for repeated experiments. The distance to where deformation of the inner wall begins for various densities is reported. This result is compared with the microwave interferometer measurements.

Driving Ability of HMX based Aluminized Explosive Affected by the Reaction Degree of Aluminum Powder

Science.gov (United States)

Duan, Yingliang

2017-06-01

Due to the time scale of aluminum reaction, the detonation process of the aluminized explosive becomes very complex, and there is less agreement on the reaction mechanism of aluminum powder. If the reaction of aluminum occurs in the reaction zone, the energy released will further strengthen the work ability of detonation wave. So it is very important for characterizing the detonation parameters and detonation driving ability to accurately understand the role of aluminum powder in the reaction zone. In this paper, detonation driving process of HMX based aluminized explosive was studied by cylinder test, obtaining the expansion track of cylinder wall. In order to further research the reaction degree (λ) of aluminum in the reaction zone, the thermodynamic program VHL was used to calculate the detonation process at different reaction degrees, obtaining the parameters of detonation products thermodynamic state. Using the dynamic software LS-DYNA and the JWL equation of state by fitting the pressure and relative volume relationship, the cylinder test was simulated. Compared with the experimental results, when the reaction degree is 20%, the driving ability is found to be in agreement with measured ones. It is concluded that the driving ability of HMX based aluminized explosive can be more accurately characterized by considering the reaction degree of aluminum powder in the reaction zone.

IRIS Toxicological Review of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (RDX) (External Review Draft)

Science.gov (United States)

The IRIS Toxicological Review of Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was released for external peer review in September 2016. The EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis suppor...

Effects of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites on cricket (Acheta domesticus) survival and reproductive success

Energy Technology Data Exchange (ETDEWEB)

Zhang Baohong [Institute of Environmental and Human Health (TIEHH), and Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409-1163 (United States); Freitag, Christina M. [Institute of Environmental and Human Health (TIEHH), and Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409-1163 (United States); Canas, Jaclyn E. [Institute of Environmental and Human Health (TIEHH), and Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409-1163 (United States); Cheng Qiuqiong [Institute of Environmental and Human Health (TIEHH), and Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409-1163 (United States); Anderson, Todd A. [Institute of Environmental and Human Health (TIEHH), and Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409-1163 (United States)]. E-mail: todd.anderson@tiehh.ttu.edu

2006-11-15

The effect of two major hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites, hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX), on cricket (Acheta domesticus) survival and reproduction was studied. RDX metabolites did not have adverse effects on cricket survival, growth, and egg production. However, MNX and TNX did affect egg hatching. MNX and TNX were more toxic in spiked-sand than in topical tests. TNX was more toxic to egg than MNX. Developmental stage and exposure time affected hatching. After 30 days exposure to MNX or TNX, the EC{sub 2}, EC{sub 5}, and EC{sub 95} were 47, 128, and 247 {mu}g/g for TNX, and 65, 140, and 253 {mu}g/g for MNX in topical tests. The ECs for 20, 50, and 95 were 21, 52, and 99 {mu}g/g for MNX, and 12, 48, and 97 {mu}g/g for TNX in sand. No gross abnormalities in cricket nypmhs were observed in all experiments indicating that neither TNX or MNX is teratogenic in this assay. - RDX metabolites did not have adverse effects on cricket survival, growth, and egg production, but adversely affected egg hatching.

Effects of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites on cricket (Acheta domesticus) survival and reproductive success

International Nuclear Information System (INIS)

Zhang Baohong; Freitag, Christina M.; Canas, Jaclyn E.; Cheng Qiuqiong; Anderson, Todd A.

2006-01-01

The effect of two major hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites, hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX), on cricket (Acheta domesticus) survival and reproduction was studied. RDX metabolites did not have adverse effects on cricket survival, growth, and egg production. However, MNX and TNX did affect egg hatching. MNX and TNX were more toxic in spiked-sand than in topical tests. TNX was more toxic to egg than MNX. Developmental stage and exposure time affected hatching. After 30 days exposure to MNX or TNX, the EC 2 , EC 5 , and EC 95 were 47, 128, and 247 μg/g for TNX, and 65, 140, and 253 μg/g for MNX in topical tests. The ECs for 20, 50, and 95 were 21, 52, and 99 μg/g for MNX, and 12, 48, and 97 μg/g for TNX in sand. No gross abnormalities in cricket nypmhs were observed in all experiments indicating that neither TNX or MNX is teratogenic in this assay. - RDX metabolites did not have adverse effects on cricket survival, growth, and egg production, but adversely affected egg hatching

Designing an ultra-sensitive aptasensor based on an AgNPs/thiol-GQD nanocomposite for TNT detection at femtomolar levels using the electrochemical oxidation of Rutin as a redox probe.

Science.gov (United States)

Shahdost-Fard, Faezeh; Roushani, Mahmoud

2017-01-15

In this paper, for the first time a highly sensitive and low-cost electrochemical aptasensor was fabricated based on a silver nanoparticles/thiol functionalized graphene quantum dot (AgNPs/thiol-GQD) nanocomposite for the measurement of 2,4,6-Trinitrotoluen (TNT) as a nitroaromatic explosive. For the first time Rutin (RU) as a biological molecule with inherent properties was used as the redox probe in the development of the TNT aptasensor was used. The system was based on a TNT-binding aptamer which is covalently attached onto the surface of a glassy carbon electrode (GCE) modified with the nanocomposite for the formation of a sensing layer and improving the performance of the aptasensor. Using the proposed nanocomposite provides a specific platform with increased surface area which is capable of loading more Aptamer (Ap) molecules as a receptor element of TNT on the electrode surface. So, TNT molecules is in an upward position to be measured and the obtained results indicate that the aptasensor exhibits two wide linear ranges and an unprecedented LOD compared with previously reported analytical methods for TNT detection. Applicability of the developed aptasensor to easily detect TNT in real samples was evaluated. It seems that the proposed strategy can be expanded to other nanoparticles and is expected to have promising implications in the design of electrochemical sensors or biosensors for the detection of various targets. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of high shock pressures and pore morphology on hot spot mechanisms in HMX

Science.gov (United States)

Springer, H. K.; Tarver, C. M.; Bastea, S.

2017-01-01

The shock initiation and detonation behavior of heterogeneous solid explosives is governed by its microstructure and reactive properties. New additive manufacturing techniques offer unprecedented control of explosive microstructures previously impossible, enabling us to develop novel explosives with tailored shock sensitivity and detonation properties. Since microstructure-performance relationships are not well established for explosives, there is little material design guidance for these manufacturing techniques. In this study, we explore the effects of high shock pressures (15-38 GPa) with long shock durations and different pore morphologies on hot spot mechanisms in HMX. HMX is chosen as the model material because we have experimental data on many of the chemical-thermal-mechanical properties required for pore collapse simulations. Our simulations are performed using the multi-physics arbitrary Lagrangian Eulerian finite element hydrocode, ALE3D, with Cheetah-based models for the unreacted and the product equation-of-states. We use a temperature-dependent specific heat with the unreacted equation-of-state and a temperature-dependent viscosity model to ensure accurate shock temperatures for subsequent chemistry. The Lindemann Law model is used for shock melting in HMX. In contrast to previous pore collapse studies at lower shock pressures (≤10 GPa) in HMX and shorter post-collapse burning times, our calculations show that shock melting occurs above 15 GPa due to higher bulk heating and a prominent elongated ("jet-like") hot spot region forms at later times. The combination of the elongated, post-collapse hot spot region and the higher bulk heating with increasing pressure dramatically increases the growth rate of reaction. Our calculations show that the reaction rate, dF/dt, increases with increasing shock pressure. We decompose the reaction rate into ignition ((dF/dt)ig) and growth ((dF/dt)gr) phases to better analyze our results. We define the ignition phase

Studies on compatibility of energetic materials by thermal methods

Directory of Open Access Journals (Sweden)

Maria Alice Carvalho Mazzeu

2010-04-01

Full Text Available The chemical compatibility of explosives, pyrotechnics and propellants with those materials is studied to evaluate potential hazards when in contact with other materials during production, storage and handling. Compatibility can be studied by several thermal methods as DSC (differential scanning calorimetry, TG (Thermogravimetry, VST (Vacuum stability test and others. The test methods and well defined criteria are the most important elements when a compatibility study is being accomplished. In this paper, the compatibility of two very important high explosives used in ammunition, RDX (Cyclo-1,3,5-trimethylene-2,4,6-trinitramine and HMX (Cyclotetramethylene tetranitramine was studied with the materials: fluoroelastomer (Viton and powdered aluminum (Al, using DSC and VST methods. The criteria to judge the compatibility between materials is based on a standardization agreement (STANAG 4147, 2001, and the final conclusion is that explosives and this materials are compatible, but in DSC it was observed that the peak of decomposition temperature of the admixture of RDX with Al decreased in 3º C and another peak appeared after the decomposition peak.

Evaluation of the metabolic fate of munitions material (TNT & RDX) in plant systems and initial assessment of material interaction with plant genetic material (DNA). Initial assessment of plant DNA adducts as biomarkers

Energy Technology Data Exchange (ETDEWEB)

Harvey, S.D.; Clauss, T.W.; Fellows, R.J.; Cataldo, D.A.

1995-08-01

Genetic damage to deoxyribonucleic acid (DNA) has long been suspected of being a fundamental event leading to cancer. A variety of causal factors can result in DNA damage including photodimerization of base pairs, ionizing radiation, specific reaction of DNA with environmental pollutants, and nonspecific oxidative damage caused by the action of highly reactive oxidizing agents produced by metabolism. Because organisms depend on an unadulterated DNA template for reproduction, DNA repair mechanisms are an important defense for maintaining genomic integrity. The objective of this exploratory project was to evaluate the potential for TNT to form DNA adducts in plants. These adducts, if they exist in sufficient quantities, could be potential biomarkers of munitions exposure. The ultimate goal is to develop a simple analytical assay for the determination of blomarkers that is indicative of munitions contamination. DNA repair exists in dynamic equilibrium with DNA damage. Repair mechanisms are capable of keeping DNA damage at remarkably low concentrations provided that the repair capacity is not overwhelmed.

Thermochemistry of mixed explosives

International Nuclear Information System (INIS)

Janney, J.L.; Rogers, R.N.

1982-01-01

In order to predict thermal hazards of high-energy materials, accurate kinetics constants must be determined. Predictions of thermal hazards for mixtures of high-energy materials require measurements on the mixtures, because interactions among components are common. A differential-scanning calorimeter (DSC) can be used to observe rate processes directly, and isothermal methods enable detection of mechanism changes. Rate-controlling processes will change as components of a mixture are depleted, and the correct depletion function must be identified for each specific stage of a complex process. A method for kinetics measurements on mixed explosives can be demonstrated with Composition B is an approximately 60/40 mixture of RDX and TNT, and is an important military explosive. Kinetics results indicate that the mator process is the decomposition of RDX in solution in TNT with a perturbation caused by interaction between the two components. It is concluded that a combination of chemical kinetics and experimental self-heating procedures provides a good approach to the production of predictive models for thermal hazards of high-energy materials. Systems involving more than one energy-contributing component can be studied. Invalid and dangerous predictive models can be detected by a failure of agreement between prediction and experiment at a specific size, shape, and density. Rates of thermal decomposition for Composition B appear to be modeled adequately for critical-temperature predictions with the following kinetics constants: E = 180.2 kJ mole -1 and Z = 4.62 X 10 16 s -1

Pengaruh Tandem Booster TNT Terhadap Kecepatan Detonasi Campuran Bahan Peledak Tepung Kalium Klorat, Sulfur Dan Aluminium Sebagai Bahan Peldak High Explosive

OpenAIRE

Tarigan, Tarsim

2010-01-01

There are a research on velocity of detonation explosives from Improvised Bomb with potassium chlorate, sulfur and aluminum with a composition of 65:20:15% (weight / weight), 70 mesh, galvanized pipes and containers with some blasting mechanism, starts with an explosion that ignite by a improvise detonator, factory detonator without a booster, factory detonator with a tandem booster TNT, and TNT booster modifications by adding a layer of Pb plate and make a cavity between the main booster ch...

A Literature Review - Problem Definition Studies on Selected Toxic Chemicals. Volume 3. Occupational Health and Safety Aspects of 2,4,6-Trinitrotoluene (TNT)

Science.gov (United States)

1978-04-01

crude liver extract, yellow bone marrow extract, a high vitamin (C and B complex) and high caloric diet . However, in spite of intensive treatment, the...protein-rich diet . . . . . 40 B. Effect of Other Food Additives . . . . . . . . . . . 40Si. Vitamin C . . . . . . ... . . . . . . . .. .. 40 ii...uncommon. Hassman (86) in 1971, in a review article about TNT reported that both hypo - and hyper-menorrhea occur in women exposed to TNT. f

Laboratory Demonstration of Abiotic Technologies for Removal of RDX from a Process Waste Stream

Science.gov (United States)

2010-06-01

calcium carbonate CSTR continuous stirred tank reactor d day DoD Department of Defense gal gallons gpd gallons per day RDX hexahydro-1,3,5... CSTR ), and (c) Plug flow reactor. a batch reactor may be used if the desired reaction occurs while the reactor volume is inconstant (i.e., during the...products from the reactor system. Con- tinuous flow reactors may be further divided into continuous stirred tank reactors ( CSTRs ) and plug or pipe flow

Proceedings, QCD-TNT-III, From Quarks and Gluons to Hadronic Matter: A Bridge too Far?

CERN Document Server

2013-01-01

In the third edition of the QCD-TNT workshop the traditional focus of the last two editions (that is gaining a firmer grasp on the infrared behavior of the QCD Green's functions) will be slightly shifted towards attempts to implement the transition from the fundamental (quarks and gluons) to the effective (mesons and hadrons) degrees of freedom. So in addition to the traditional QCD-TNT themes (e.g., confinement, gluon mass generation, lattice simulations in different gauges, QCD at finite temperature and density) we plan to have more phenomenologically oriented topics (e.g., experimental reviews, determination of form factors from first principle, construction of Bethe-Salpeter kernels). In addition, a special session will be dedicated to review talks, summarizing the state-of-the-art, as well as highlighting the future perspectives, of simulating non-Abelian gauge fields using ultracold neutral atoms trapped in optical lattices, and other systems.

Carbon cluster formation during thermal decomposition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine and 1,3,5-triamino-2,4,6-trinitrobenzene high explosives from ReaxFF reactive molecular dynamics simulations.

Science.gov (United States)

Zhang, Luzheng; Zybin, Sergey V; van Duin, Adri C T; Dasgupta, Siddharth; Goddard, William A; Kober, Edward M

2009-10-08

We report molecular dynamics (MD) simulations using the first-principles-based ReaxFF reactive force field to study the thermal decomposition of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) at various densities and temperatures. TATB is known to produce a large amount (15-30%) of high-molecular-weight carbon clusters, whereas detonation of nitramines such as HMX and RDX (1,3,5-trinitroperhydro-1,3,5-triazine) generate predominantly low-molecular-weight products. In agreement with experimental observation, these simulations predict that TATB decomposition quickly (by 30 ps) initiates the formation of large carbonaceous clusters (more than 4000 amu, or approximately 15-30% of the total system mass), and HMX decomposition leads almost exclusively to small-molecule products. We find that HMX decomposes readily on this time scale at lower temperatures, for which the decomposition rate of TATB is about an order of magnitude slower. Analyzing the ReaxFF MD results leads to the detailed atomistic structure of this carbon-rich phase of TATB and allows characterization of the kinetics and chemistry related to this phase and their dependence on system density and temperature. The carbon-rich phase formed from TATB contains mainly polyaromatic rings with large oxygen content, leading to graphitic regions. We use these results to describe the initial reaction steps of thermal decomposition of HMX and TATB in terms of the rates for forming primary and secondary products, allowing comparison to experimentally derived models. These studies show that MD using the ReaxFF reactive force field provides detailed atomistic information that explains such macroscopic observations as the dramatic difference in carbon cluster formation between TATB and HMX. This shows that ReaxFF MD captures the fundamental differences in the mechanisms of such systems and illustrates how the ReaxFF may be applied to model complex chemical phenomena

The kinetic of mass loss of grades A and B of melted TNT by isothermal and non-isothermal gravimetric methods

Directory of Open Access Journals (Sweden)

Hamid Reza Pouretedal

2018-04-01

Full Text Available The kinetic and activation energy of mass loss of two grades of melted TNT explosive, grade A and grade B, with freezing points of 80.57 and 78.15 °C, respectively, were studied by isothermal and non-isothermal gravimetric methods. In isothermal method, the mass loss of samples in containers of glass and aluminum was followed in temperatures of 80, 90 and 100 °C. The kinetic of the mass loss of the samples in the aluminum container was higher than the kinetic of it in the glass container that can be related to the effects of heat transfer and catalytic of aluminum metal. Also, the presence of impurities in grade B was due to increasing of kinetic of mass loss of it versus grade A. The non-isothermal curves were obtained in range of 30–330 °C at heating rates of 10, 15 and 20 °C⋅min−1. The TG/DTG data were used for determination of activation energy (Ea of mass loss of TNT samples upon degradation by using Ozawa, Kissinger, Ozawa-Flynn-Wall (OFW and Kissinger-Akahira-Sunose (KAS methods as model free methods. The activation energies of grades of A and B of TNT was obtained 99–120 and 66–70 kJ mol−1, respectively. The lower values of activation energy of the degradation reaction of grade B confirm the effect of impurities in the kinetics of mass loss of this grade. Keywords: TNT, Isothermal, Non-isothermal, Kinetic, Mass loss

Combustion synthesis and catalytic activity of LaCoO{sub 3} for HMX thermal decomposition

Energy Technology Data Exchange (ETDEWEB)

Wei, Zhi-Xian; Chi, Ying-Nan [Department of Chemistry, Institute for Chemical Physics, Beijing Institute of Technology (China); Hu, Chang-Wen [State Key Laboratory of Explosion Science, Technology Beijing Institute of Technology, Beijing (China); Liu, Hai-Yan [Department of Chemistry, Science Institute, North China University, Taiyuan, Shanxi (China)

2009-10-15

Perovskite-type LaCoO{sub 3} was prepared by stearic acid solution combustion method and characterized by XRD, DSC-TG, and XPS techniques. The catalytic activities of LaCoO{sub 3} for HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) thermal decomposition were investigated. The as-prepared LaCoO{sub 3} shows higher activity than the calcined one. This could be due to higher concentration of surface-adsorbed oxygen and hydroxyl species as well as higher BET surface area of the as-prepared LaCoO{sub 3}. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

Destruction of energetic materials by supercritical water oxidation

International Nuclear Information System (INIS)

Beulow, S.J.; Dyer, R.B.; Harradine, D.M.; Robinson, J.M.; Oldenborg, R.C.; Funk, K.A.; McInroy, R.E.; Sanchez, J.A.; Spontarelli, T.

1993-01-01

Supercritical water oxidation is a relatively low-temperature process that can give high destruction efficiencies for a variety of hazardous chemical wastes. Results are presented examining the destruction of high explosives and propellants in supercritical water and the use of low temperature, low pressure hydrolysis as a pretreatment process. Reactions of cyclotrimethylene trinitramine (RDX), cyclotetramethylene tetranitramine (HMX), nitroguanidine (NQ), pentaerythritol tetranitrate (PETN), and 2,4,6-trinitrotoluene (TNT) are examined in a flow reactor operated at temperatures between 400 degrees C and 650 degrees C. Explosives are introduced into the reactor at concentrations below the solubility limits. For each of the compounds, over 99.9% is destroyed in less than 30 seconds at temperatures above 600 degrees C. The reactions produce primarily N 2 , N 2 O,CO 2 , and some nitrate and nitrite ions. The distribution of reaction products depends on reactor pressure, temperature, and oxidizer concentration. Kinetics studies of the reactions of nitrate and nitrite ions with various reducing reagents in supercritical water show that they can be rapidly and completely destroyed at temperatures above 525 degrees C. The use of slurries and hydrolysis to introduce high concentrations of explosives into a supercritical water reactor is examined. For some compounds the rate of reaction depends on particle size. The hydrolysis of explosives at low temperatures (<100 degrees C) and low pressures (<1 atm) under basic conditions produces water soluble, non-explosive products which are easily destroyed by supercritical water oxidation. Large pieces of explosives (13 cm diameter) have been successfully hydrolyzed. The rate, extent, and products of the hydrolysis depend on the type and concentration of base. Results from the base hydrolysis of triple base propellant M31A1E1 and the subsequent supercritical water oxidation of the hydrolysis products are presented

Recent advances in the molten salt technology for the destruction of energetic materials

International Nuclear Information System (INIS)

Upadhye, R.S.; Watkins, B.E.; Pruneda, C.O.

1995-11-01

The DOE has thousands of pounds of energetic materials which result from dismantlement operations at the Pantex Plant. The authors have demonstrated the Molten Salt Destruction (MSD) Process for the treatment of explosives and explosive-containing wastes on a 1.5 kilogram of explosive per hour scale and are currently building a 5 kilogram per hour unit. MSD converts the organic constituents of the waste into non-hazardous substances such as carbon dioxide, nitrogen and water. Any inorganic constituents of the waste, such as binders and metallic particles, are retained in the molten salt. The destruction of energetic material waste is accomplished by introducing it, together with air, into a crucible containing a molten salt, in this case a eutectic mixture of Na, K, and Li carbonates. The following pure component DOE and DoD explosives have been destroyed in LLNL's experimental unit at their High Explosives Applications Facility (HEAF): ammonium picrate, HMX, K-6, NQ, NTO, PETN, RDX, TATB, and TNT. In addition, the following formulations were also destroyed: Comp B, LX-10, LX-16, LX-17, PBX-9404, and XM46, a US Army liquid gun propellant. In this 1.5 kg/hr unit, the fractions of carbon converted to CO and of chemically bound nitrogen converted to NOx were found to be well below 1T. In addition to destroying explosive powders and molding powders the authors have also destroyed materials that are typical of real world wastes. These include shavings from machined pressed parts of plastic bonded explosives and sump waste containing both explosives and non-explosive debris. Based on the information obtained on the smaller unit, the authors have constructed a 5 kg/hr MSD unit, incorporating LLNL's advanced chimney design. This unit is currently under shakedown tests and evaluation

A theoretical study of the relaxation of a phenyl group chemisorbed to an RDX freestanding thin film

Energy Technology Data Exchange (ETDEWEB)

Pereverzev, Andrey, E-mail: pereverzeva@missouri.edu; Sewell, Thomas D., E-mail: sewellt@missouri.edu [Department of Chemistry, University of Missouri-Columbia, Columbia, Missouri 65211-7600 (United States)

2016-08-07

Energy relaxation from an excited phenyl group chemisorbed to the surface of a crystalline thin film of α-1,3,5-trinitro-1,3,5-triazacyclohexane (α-RDX) at 298 K and 1 atm is simulated using molecular dynamics. Two schemes are used to excite the phenyl group. In the first scheme, the excitation energy is added instantaneously as kinetic energy by rescaling momenta of the 11 atoms in the phenyl group. In the second scheme, the phenyl group is equilibrated at a higher temperature in the presence of static RDX geometries representative of the 298 K thin film. An analytical model based on ballistic phonon transport that requires only the harmonic part of the total Hamiltonian and includes no adjustable parameters is shown to predict, essentially quantitatively, the short-time dynamics of the kinetic energy relaxation (∼200 fs). The dynamics of the phenyl group for times longer than about 6 ps follows exponential decay and agrees qualitatively with the dynamics described by a master equation. Long-time heat propagation within the bulk of the crystal film is consistent with the heat equation.

An evaluation of the environmental fate and behavior of munitions materiel (tetryl and polar metabolites of TNT) in soil and plant systems

International Nuclear Information System (INIS)

Fellows, R.J.; Harvey, S.D.; Cataldo, D.A.

1993-09-01

A preliminary study was conducted to elucidate the nature of the polar metabolites reported for plant tissues and xylem exudates following root accumulation of trinitrotoluene. Studies focused on the nature of the proposed conjugates of TNT-residues in xylem exudates of bush beam plants. Use of enzymatic methods failed to demonstrate that the conjugates were carbohydrate based, but acid hydrolysis indicated that the conjugates may be protein based. Of the five polar conjugates isolated from exudates, the presence of aminodinitrotoluene isomers and one unknown TNT residue was demonstrated

RDX binds to the convulsant site of the GABAA receptor and increases spontaneous firing rates of cortical neurons in vitro

Science.gov (United States)

RDX (hexahydro-1 ,3,5-trinitro-1 ,3,5-triazine, hexogen, Royal Demolition eXplosive) is an explosive widely used by the military and has been found in soil and ground water in and surrounding training ranges, creating potential hazards to the environment and human health. Oral RD...

TNT Maritime Interdiction Operation Experiments: Enabling Radiation Awareness and Geographically Distributed Collaboration for Network-Centric Maritime Interdiction Operations [Preprint

National Research Council Canada - National Science Library

Bordetsky, Alex; Dougan, Arden; Chiann, Foo Y; Kilberg, Andres

2007-01-01

.... This joint Naval Postgraduate School (NPS)-Lawrence Livermore National Laboratory (LLNL) project, supported by partners from Sweden, Austria, and Singapore is based on the NPS Tactical Network Topology (TNT...

X-ray photoelectron spectroscopy and paramagnetic resonance evidence for shock-induced intramolecular bond breaking in some energetic solids

Science.gov (United States)

Owens, F. J.; Sharma, J.

1980-03-01

Solid samples of 1,3,5, trinitro 1,3,5, triazacyclohexane (RDX), trinitrotoluene (TNT), and ammonium nitrate were subjected to shock pulses of strength and duration less than the threshold to cause detonation. The recovered shocked samples were studied by x-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR). The results of these measurements indicate that the shock pulse either broke or altered the internal bonds of the molecules of the solid. The results of the shock decomposition are compared with measurements of the uv and slow thermal decomposition of these materials using the same experimental techniques.

Novel methods for detecting buried explosive devices

Energy Technology Data Exchange (ETDEWEB)

Kercel, S.W.; Burlage, R.S.; Patek, D.R.; Smith, C.M. [Oak Ridge National Lab., TN (United States); Hibbs, A.D.; Rayner, T.J. [Quantum Magnetics, Inc., San Diego, CA (United States)

1997-04-01

Oak Ridge National Laboratory (ORNL) and Quantum Magnetics, Inc. (QM) are exploring novel landmine detection technologies. Technologies considered here include bioreporter bacteria, swept acoustic resonance, nuclear quadrupole resonance (NQR), and semiotic data fusion. Bioreporter bacteria look promising for third-world humanitarian applications; they are inexpensive, and deployment does not require high-tech methods. Swept acoustic resonance may be a useful adjunct to magnetometers in humanitarian demining. For military demining, NQR is a promising method for detecting explosive substances; of 50,000 substances that have been tested, none has an NQR signature that can be mistaken for RDX or TNT. For both military and commercial demining, sensor fusion entails two daunting tasks, identifying fusible features in both present-day and emerging technologies, and devising a fusion algorithm that runs in real-time on cheap hardware. Preliminary research in these areas is encouraging. A bioreporter bacterium for TNT detection is under development. Investigation has just started in swept acoustic resonance as an approach to a cheap mine detector for humanitarian use. Real-time wavelet processing appears to be a key to extending NQR bomb detection into mine detection, including TNT-based mines. Recent discoveries in semiotics may be the breakthrough that will lead to a robust fused detection scheme.

Using of multi-walled carbon nanotubes electrode for adsorptive stripping voltammetric determination of ultratrace levels of RDX explosive in the environmental samples.

Science.gov (United States)

Rezaei, Behzad; Damiri, Sajjad

2010-11-15

A study of the electrochemical behavior and determination of RDX, a high explosive, is described on a multi-walled carbon nanotubes (MWCNTs) modified glassy carbon electrode (GCE) using adsorptive stripping voltammetry and electrochemical impedance spectroscopy (EIS) techniques. The results indicated that MWCNTs electrode remarkably enhances the sensitivity of the voltammetric method and provides measurements of this explosive down to the sub-mg/l level in a wide pH range. The operational parameters were optimized and a sensitive, simple and time-saving cyclic voltammetric procedure was developed for the analysis of RDX in ground and tap water samples. Under optimized conditions, the reduction peak have two linear dynamic ranges of 0.6-20.0 and 8.0-200.0 mM with a detection limit of 25.0 nM and a precision of <4% (RSD for 8 analysis). Copyright © 2010 Elsevier B.V. All rights reserved.

Sustainable Range Management of RDX and TNT by Phytoremediation with Engineered Plants

Science.gov (United States)

2016-04-01

crop has recently led to the development and publication of efficient transformation techniques. Switchgrass is climatically adapted to grow...the medium, for the first round of selection. Petri dishes were incubated in the culture room under white fluorescent lamps (1900 lux) with 16 hr...with shaking overnight. The GFP signal was observed under UV light. 78 Primers for promoter amplification PL Z1 Ppsbaf2

Energetic materials under high pressures and temperatures: stability, polymorphism and decomposition of RDX

International Nuclear Information System (INIS)

Dreger, Z A

2012-01-01

A recent progress in understanding the response of energetic crystal of cyclotrimethylene trinitramine (RDX) to high pressures and temperatures is summarized. The optical spectroscopy and imaging studies under static compression and high temperatures provided new insight into phase diagram, polymorphism and decomposition mechanisms at pressures and temperatures relevant to those under shock compression. These results have been used to aid the understanding of processes under shock compression, including the shock-induced phase transition and identification of the crystal phase at decomposition. This work demonstrates that studies under static compression and high temperatures provide important complementary route for elucidating the physical and chemical processes in shocked energetic crystals.

Critical Analysis of Nitramine Decomposition Data: Product Distributions from HMX and RDX Decomposition

Science.gov (United States)

1985-06-01

12. It was stated that analysis of the gaseous products showed that they consisted of N2O, NO, N2, CO, CO2, F^CO and traces of N,* The products of...IR, UV and mass spectrometry. These were (yields summarized in Table 1) as follows: No 1 N2O, NO, CO2, CO, HCN, CH2O, and I^O. NO2 and a trace ...Ramirez, "Reaction of Gem-Nitronitroso Compounds with Triethyl Phosphite ," Tetrahedron, Vol. 29, p. 4195, 1973. J. Jappy and P.N. Preston

Analysis of Wastewater for Organic Compounds Unique to RDX/HMX manufacturing and Processing

Science.gov (United States)

1979-12-01

manufacture of acetic anhydride and the concentration of weak acetic acid, recovered at Area B, to yield * Holston Defense Corporation 2 Kingsport...washing nor Soxhlet extraction techniques proved to be effective in recovering the organic compounds from the type of activated carbon available at the...ice ?nd acetone mixture.J Approximately one liter of dewater yielded approximately 200 mg (0.2 grams) of freeze-dried solids: These solids were

Characterization of polymorphic states in energetic samples of 1,3,5-trinitro-1,3,5-triazine (RDX) fabricated using drop-on-demand inkjet technology.

Science.gov (United States)

Emmons, Erik D; Farrell, Mikella E; Holthoff, Ellen L; Tripathi, Ashish; Green, Norman; Moon, Raphael P; Guicheteau, Jason A; Christesen, Steven D; Pellegrino, Paul M; Fountain, Augustus W

2012-06-01

The United States Army and the first responder community are evaluating optical detection systems for the trace detection of hazardous energetic materials. Fielded detection systems must be evaluated with the appropriate material concentrations to accurately identify the residue in theater. Trace levels of energetic materials have been observed in mutable polymorphic phases and, therefore, the systems being evaluated must be able to detect and accurately identify variant sample phases observed in spectral data. In this work, we report on the novel application of drop-on-demand technology for the fabrication of standardized trace 1,3,5-trinitro-1,3,5-triazine (RDX) samples. The drop-on-demand sample fabrication technique is compared both visually and spectrally to the more commonly used drop-and-dry technique. As the drop-on-demand technique allows for the fabrication of trace level hazard materials, concerted efforts focused on characterization of the polymorphic phase changes observed with low concentrations of RDX commonly used in drop-on-demand processing. This information is important when evaluating optical detection technologies using samples prepared with a drop-on-demand inkjet system, as the technology may be "trained" to detect the common bulk α phase of the explosive based on its spectral features but fall short in positively detecting a trace quantity of RDX (β-phase). We report the polymorphic shifts observed between α- and β-phases of this energetic material and discuss the conditions leading to the favoring of one phase over the other.

Mirrored continuum and molecular scale simulations of the ignition of gamma phase RDX

Science.gov (United States)

Stewart, D. Scott; Chaudhuri, Santanu; Joshi, Kaushik; Lee, Kibaek

2017-01-01

We describe the ignition of an explosive crystal of gamma-phase RDX due to a thermal hot spot with reactive molecular dynamics (RMD), with first-principles trained, reactive force field based molecular potentials that represents an extremely complex reaction network. The RMD simulation is analyzed by sorting molecular product fragments into high and low molecular weight groups, to represent identifiable components that can be interpreted by a continuum model. A continuum model based on a Gibbs formulation has a single temperature and stress state for the mixture. The continuum simulation that mirrors the atomistic simulation allows us to study the atomistic simulation in the familiar physical chemistry framework and provides an essential, continuum/atomistic link.

Effect of two major N-nitroso hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites on earthworm reproductive success

International Nuclear Information System (INIS)

Zhang Baohong; Cox, Stephen B.; McMurry, Scott T.; Jackson, W. Andrew; Cobb, George P.; Anderson, Todd A.

2008-01-01

Soil and topical tests were employed to investigate the effect of two N-nitroso metabolites of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) on earthworm reproduction. The lowest observed effect concentration (LOEC) for cocoon production and hatching was 50 mg/kg for both hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX) in soil. MNX and TNX also significantly affected cocoon hatching in soil (p 20 values for MNX were 8.7 and 8.8 mg/kg for cocoon and juvenile production, respectively, compared to 9.2 and 9.1 mg/kg for TNX, respectively. The EC 20 values for the total number of cocoon hatchlings were 3.1 and 4.7 mg/kg for MNX and TNX, respectively, in soil and 4.5 and 3.1 mg/L in the topical test. Both MNX and TNX inhibited cocoon production and hatching, suggesting that they may have a negative affect on soil ecosystems at contaminated sites. - RDX metabolites affect earthworm cocoon production and hatching

'Test n Treat (TnT)': a cluster-randomised feasibility trial of frequent, rapid-testing and same-day, on-site treatment to reduce rates of chlamydia in high-risk further education college students: statistical analysis plan.

Science.gov (United States)

Phillips, Rachel; Oakeshott, Pippa; Kerry-Barnard, Sarah; Reid, Fiona

2018-06-05

There are high rates of sexually transmitted infections (STIs) in ethnically diverse, sexually active students aged 16-24 years attending London further education (FE) colleges. However, uptake of chlamydia screening remains low. The TnT study aims to assess the feasibility of conducting a future trial in FE colleges to investigate if frequent, rapid, on-site testing and treatment (TnT) reduces chlamydia rates. This article presents the statistical analysis plan for the main study publication as approved and signed off by the Trial Management Group prior to the first data extraction for the final report. TnT is a cluster-randomised feasibility trial conducted over 7 months with parallel qualitative and economic assessments. Colleges will be randomly allocated into the intervention (TnT) or the control group (no TnT). Six FE colleges in London will be included. At each college for 2 days, 80 consecutive sexually active students aged 16-24 years (total 480 students across all six colleges) will be recruited from public areas and asked to provide baseline samples. One and 4 months after recruitment intervention colleges will be visited on two consecutive days by the TnT team where participating students will be texted and invited to come for same-day, on-site, rapid chlamydia testing and, if positive, treatment. Participants in the control colleges will receive 'thank you' texts 1 and 4 months after recruitment. Seven months after recruitment, participants from both groups will be invited to complete questionnaires and provide samples for TnT. All samples will be tested, and same-day treatment offered to participants with positive results. Key feasibility outcomes include: recruitment rates, testing and treatment uptake rates (at 1 and 4 months) and follow-up rates (at 7 months). ISRCTN 58038795 . Registered on 31 August 2016.

Charge transport studies in donor-acceptor block copolymer PDPP-TNT and PC71BM based inverted organic photovoltaic devices processed in room conditions

International Nuclear Information System (INIS)

Srivastava, Shashi B.; Singh, Samarendra P.; Sonar, Prashant

2015-01-01

Diketopyrrolopyrole-naphthalene polymer (PDPP-TNT), a donor-acceptor co-polymer, has shown versatile behavior demonstrating high performances in organic field-effect transistors (OFETs) and organic photovoltaic (OPV) devices. In this paper we report investigation of charge carrier dynamics in PDPP-TNT, and [6,6]-phenyl C 71 butyric acid methyl ester (PC71BM) bulk-heterojunction based inverted OPV devices using current density-voltage (J-V) characteristics, space charge limited current (SCLC) measurements, capacitance-voltage (C-V) characteristics, and impedance spectroscopy (IS). OPV devices in inverted architecture, ITO/ZnO/PDPP-TNT:PC71BM/MoO 3 /Ag, are processed and characterized at room conditions. The power conversion efficiency (PCE) of these devices are measured ∼3.8%, with reasonably good fill-factor 54.6%. The analysis of impedance spectra exhibits electron’s mobility ∼2 × 10 −3 cm 2 V −1 s −1 , and lifetime in the range of 0.03-0.23 ms. SCLC measurements give hole mobility of 1.12 × 10 −5 cm 2 V −1 s −1 , and electron mobility of 8.7 × 10 −4 cm 2 V −1 s −1

Effect of Simulated Weathering and Aging of TNT in Amended Sandy Loam Soil on Toxicity to the Enchytraeid Worm, Enchytreaeus Crypticus

National Research Council Canada - National Science Library

Kuperman, Roman G; Checkai, Ronald T; Simini, Michael; Phillips, Carlton T; Kolakowski, Jan E; Kurnas, Carl W

2006-01-01

...) for the ecological risk assessment of contaminants at Superfund sites. Insufficient information for TNT to generate Eco-SSL for soil invertebrates has necessitated standardized toxicity testing to fill the data gap...

Studies of free field and confined explosions of aluminium enriched RDX compositions

Energy Technology Data Exchange (ETDEWEB)

Trzcinski, Waldemar A.; Cudzilo, Stanislaw; Paszula, Jozef [Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland)

2007-12-15

Research on the effect of aluminium contents and its particle size on free field and confined explosions characteristics of RDX-based compositions containing 15-60% aluminium was carried out. Parameters of blast waves produced by charges of the investigated explosives detonating in an open space were measured by the use of piezoelectric gauges. Simultaneously, photodiode set-ups were used to measure light output of the detonating charges. Quasi-static pressure measurements were conducted in steel chambers of 0.15 and 7 m{sup 3} volume filled with air. Moreover, the heat of detonation was measured with a calorimetric set in a 5.6 dm{sup 3} bomb filled with argon. The results of QSP and detonation heat measurements were compared with those obtained from thermochemical calculations. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

Composting of soils/sediments and sludges containing toxic organics including high energy explosives. Final report

Energy Technology Data Exchange (ETDEWEB)

Doyle, R.C.; Kitchens, J.F.

1993-07-01

Laboratory and pilot-scale experimentation were conducted to evaluate composting as an on-site treatment technology to remediate soils contaminated with hazardous waste at DOE`s PANTEX Plant. Suspected contaminated sites within the PANTEX Plant were sampled and analyzed for explosives, other organics, and inorganic wastes. Soils in drainage ditches and playas at PANTEX Plant were found to be contaminated with low levels of explosives (including RDX, HMX, PETN and TATB). Additional sites previously used for solvent disposal were heavily contaminated with solvents and transformation products of the solvent, as well as explosives and by-products of explosives. Laboratory studies were conducted using {sup 14}C-labeled explosives and {sup 14}C-labeled diacetone alcohol contaminated soil loaded into horse manure/hay composts at three rates: 20, 30, and 40%(W/W). The composts were incubated for six weeks at approximately 60{degree}C with continuous aeration. All explosives degraded rapidly and were reduced to below detection limits within 3 weeks in the laboratory studies. {sup 14}C-degradates from {sup 14}C-RDX, {sup 14}C-HMX and {sup 14}C-TATB were largely limited to {sup 14}CO{sub 2} and unextracted residue in the compost. Volatile and non-volatile {sup 14}C-degradates were found to result from {sup 14}C-PETN breakdown, but these compounds were not identified. {sup 14}C-diacetone alcohol concentrations were significantly reduced during composting. However, most of the radioactivity was volatilized from the compost as non-{sup 14}CO{sub 2} degradates or as {sup 14}C-diacetone alcohol. Pilot scale composts loaded with explosives contaminated soil at 30% (W/W) with intermittent aeration were monitored over six weeks. Data from the pilot-scale study generally was in agreement with the laboratory studies. However, the {sup 14}C-labeled TATB degraded much faster than the unlabeled TATB. Some formulations of TATB may be more resistant to composting activity than others.

Reevaluation of a twenty-four-month chronic toxicity/carcinogenicity study of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in the B6C3F1 hybrid mouse.

Science.gov (United States)

Parker, George A; Reddy, Gunda; Major, Michael A

2006-01-01

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) has been widely used as an explosive in U.S. army munitions formulations since World War II. Two-year carcinogenicity studies revealed RDX to be noncarcinogenic in two strains of rats, but a 2-year carcinogenicity study in B6C3F1 mice revealed an increased incidence of hepatocellular neoplasms in females. Based on results of the study in B6C3F1 mice, RDX has been classified as a possible carcinogen. The authors reevaluated the archived histological sections from the B6C3F1 mouse study, using current histopathologic diagnostic criteria and interpretations. The earlier evaluation showed a statistically significant increase in the incidence of hepatocellular adenoma/carcinoma in female mice from the three highest dose groups (7, 35, and 175/100 mg/kg/day). The revaluation yielded a slightly lower incidence at each of the dose levels in female mice. The reduced number of hepatocellular neoplasms was largely due to reclassification of hepatocellular adenomas as foci of cytoplasmic alteration, in compliance with current diagnostic criteria. The reevaluation was reviewed by a pathology working group (PWG), which arrived at a consensus classification of each lesion. Based on the consensus diagnoses of the PWG, only one female group (35 mg/kg/day) showed a significant increase when compared to controls. The incidence of hepatocellular neoplasms for all groups, including the 35 mg/kg/day group, was within the reported incidence range for spontaneous hepatocellular neoplasms in female B6C3F1 mice. The increased incidence of hepatocellular neoplasms in female mice given RDX at 35 mg/kg/day was interpreted as equivocal evidence of a carcinogenic effect.

Clostridium geopurificans strain MJ1 sp. nov., a strictly anaerobic bacterium that grows via fermentation and reduces the cyclic nitramine explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX).

Science.gov (United States)

Kwon, Man Jae; Wei, Na; Millerick, Kayleigh; Popovic, Jovan; Finneran, Kevin

2014-06-01

A fermentative, non-spore forming, motile, rod-shaped bacterium, designated strain MJ1(T), was isolated from an RDX contaminated aquifer at a live-fire training site in Northwest NJ, United States. On the basis of 16S rRNA gene sequencing and DNA base composition, strain MJ1(T) was assigned to the Firmicutes. The DNA G+C content was 42.8 mol%. Fermentative growth was supported by glucose and citrate in a defined basal medium. The bacterium is a strict anaerobe that grows between at pH 6.0 and pH 8.0 and 18 and 37 °C. The culture did not grow with hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) as the electron acceptor or mineralize RDX under these conditions. However, MJ1(T) transformed RDX into MNX, methylenedinitramine, formaldehyde, formate, ammonium, nitrous oxide, and nitrate. The nearest phylogenetic relative with a validly published name was Desulfotomaculum guttoideum (95 % similarity). However, MJ1(T) was also related to Clostridium celerecrescens DSM 5628 (95 %), Clostridium indolis DSM 755 (94 %), and Clostridium sphenoides DSM 632 (94 %). DNA:DNA hybridization with these strains was between 6.7 and 58.7 percent. The dominant cellular fatty acids (greater than 5 % of the total, which was 99.0 % recovery) were 16:0 fatty acid methyl ester (FAME) (32.12 %), 18:1cis 11 dimethyl acetal (DMA) (16.47 %), 16:1cis 9 DMA (10.28 %), 16:1cis 9 FAME (8.10 %), and 18:1cis 9 DMA (5.36 %). On the basis of morphological, physiological, and phylogenetic data, Clostridium geopurificans is proposed as a new species in genus Clostridium, with strain MJ1(T) as the type strain.

Fizičko-hemijske i detonacione karakteristike nitraminskih eksploziva - RDX, HMX i CL-20

OpenAIRE

Anđelković-Lukić Mirjana

2002-01-01

U radu su prikazane fizičko-hemijske i detonacione karakteristike nitraminskih brizantnih eksploziva, heksogena i oktogena, uporedene sa osobinama novog cikličnog nitraminskog eksploziva CL-20. Novi visokobrizantni eksploziv CL-20 postoji u četiri kristalne forme, stabilne na različitim temepraturama. Ima bolje detonacione karakteristike od heksogena i oktogena veću gustinu i brzinu detonacije, all mnogo veću osetljivost na udar i trenje, reda PETN. Zbog toga se ovaj eksploziv flegmatizuje sa...

Parameters of explosives detection through tagged neutron method

Energy Technology Data Exchange (ETDEWEB)

Bagdasaryan, Kh.E.; Batyaev, V.F.; Belichenko, S.G., E-mail: consul757@mail.ru; Bestaev, R.R.; Gavryuchenkov, A.V.; Karetnikov, M.D.

2015-06-01

The potentialities of tagged neutron method (TNM) for explosives detection are examined on the basis of an idealized geometrical model. The model includes ING-27 14 MeV neutron generator with a built-in α-detector, a LYSO γ-detector and samples of material to be identified of approximately 0.3 kg each: explosives imitators (trinitrotoluene - TNT, tetryl, RDX and ammonium nitrate), legal materials (sugar, water, silk and polyethylene). The samples were unshielded or shielded by a paper layer of various thicknesses. The experimental data were interpreted by numerical simulation using a Poisson distribution of signals with the statistical parameters defined experimentally. The detection parameters were obtained by a pattern classification theory and a Bayes classifier.

Proceedings of the second workshop on thermal-non-thermal interactions in solar flares [TNT-II

International Nuclear Information System (INIS)

Phillips, K.J.H.

1989-09-01

The Second Workshop on the theme of Thermal-Non-thermal Interactions in Solar Flares (TNT-II) was held at Somerville College, University of Oxford, England, during the week of April 10-14, 1989. The keynote address, gave a view of the problems still outstanding with regard to soft and hard X-ray observations of flares. The gathering broke up into four subgroups. The subjects under discussion were: large-scale magnetic field phenomena, flare dynamics, energy release and deposition, and global energy balance. (author)

Integrated Data Collection Analysis (IDCA) Program - RDX Type II Class 5 Standard, Data Set 1

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorenson, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Moran, Jesse S. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Shelley, Timothy J. [Air Force Research Lab. (AFRL), Tyndall AFB, FL (United States); Reyes, Jose A. [Applied Research Associates, Inc., Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whipple, Richard E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2011-04-11

This document describes the results of the first reference sample material—RDX Type II Class 5—examined in the proficiency study for small-scale safety and thermal (SSST) testing of explosive materials for the Integrated Data Collection Analysis (IDCA) Program. The IDCA program is conducting proficiency testing on homemade explosives (HMEs). The reference sample materials are being studied to establish the accuracy of traditional explosives safety testing for each performing laboratory. These results will be used for comparison to results from testing HMEs. This effort, funded by the Department of Homeland Security (DHS), ultimately will put the issues of safe handling of these materials in perspective with standard military explosives. The results of the study will add SSST testing results for a broad suite of different HMEs to the literature, potentially suggest new guidelines and methods for HME testing, and possibly establish what are the needed accuracies in SSST testing to develop safe handling practices. Described here are the results for impact, friction, electrostatic discharge, and scanning calorimetry analysis of a reference sample of RDX Type II Class 5. The results from each participating testing laboratory are compared using identical test material and preparation methods wherever possible. Note, however, the test procedures differ among the laboratories. These results are then compared to historical data from various sources. The performers involved are Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Air Force Research Laboratory/ RXQL (AFRL), Indian Head Division, Naval Surface Warfare Center, (IHD-NSWC), and Sandia National Laboratories (SNL). These tests are conducted as a proficiency study in order to establish some consistency in test protocols, procedures, and experiments and to understand how to compare results when test protocols are not identical.

Surface effects on the crystallization of cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX) and the consequences for its N K X-ray emission spectrum.

Science.gov (United States)

Goldberg, Ilana G; Vila, Fernando D; Jach, Terrence

2012-10-11

Recent studies of the crystallization of cyclotrimethylene-trinitramine (RDX) have shown that the presence of the α- and β-phases of the compound is sensitive to the substrate when using drop cast crystallization methods. The specific phase has potential consequences for measurements of the nitrogen K X-ray emission spectrum (XES) that were recently reported for this compound using samples crystallized on In metal substrates. We have determined that the crystallization of RDX on a clean In metal substrate starts out completely as the β-phase but progressively incorporates the α-phase as the film thickens. In addition, we have carried out additional molecular orbital calculations of the N 1s X-ray fluorescence from the valence band, comparing the results expected from the α-and β- phases. The differences due to the presence of the β-phase instead of, or in addition to, the α-phase appear to be minimal.

The GEANT4 simulation study of the characteristic γ-ray spectrum of TNT under soil induced by DT neutron

International Nuclear Information System (INIS)

Qin Xue; Han Jifeng; Yang Chaowen

2014-01-01

The characteristic γ-ray spectrum of TNT under soil induced by DT neutron is measured based on the PFTNA demining system. GEANT4 Monte Carlo simulation toolkit is used to simulate the whole experimental procedure. The simulative spectrum is compared with the experimental spectrum. The result shows that they are mainly consistent. It is for the first time to analyze the spectrum by Monte Carlo simulation, the share of the background sources such as neutron, gamma are obtained, the contribution that the experimental apparatus such as shielding, detector sleeve, moderator make to the background is analysed. The study found that the effective gamma signal (from soil and TNT) is only 29% of the full-spectrum signal, and the background signal is more than 68% of the full-spectrum signal, which is mainly produced in the shielding and the detector sleeve. The simulation result shows that by gradually improving the shielding and the cadmium of the detector sleeve, the share of the effective gamma signal can increase to 36% and the background signal can fell 7% eventually. (authors)

Measurement and reactive burn modeling of the shock to detonation transition for the HMX based explosive LX-14

Science.gov (United States)

Jones, J. D.; Ma, Xia; Clements, B. E.; Gibson, L. L.; Gustavsen, R. L.

2017-06-01

Gas-gun driven plate-impact techniques were used to study the shock to detonation transition in LX-14 (95.5 weight % HMX, 4.5 weight % estane binder). The transition was recorded using embedded electromagnetic particle velocity gauges. Initial shock pressures, P, ranged from 2.5 to 8 GPa and the resulting distances to detonation, xD, were in the range 1.9 to 14 mm. Numerical simulations using the SURF reactive burn scheme coupled with a linear US -up / Mie-Grueneisen equation of state for the reactant and a JWL equation of state for the products, match the experimental data well. Comparison of simulation with experiment as well as the ``best fit'' parameter set for the simulations is presented.

Hot spot formation and chemical reaction initiation in shocked HMX crystals with nanovoids: a large-scale reactive molecular dynamics study.

Science.gov (United States)

Zhou, Tingting; Lou, Jianfeng; Zhang, Yangeng; Song, Huajie; Huang, Fenglei

2016-07-14

We report million-atom reactive molecular dynamic simulations of shock initiation of β-cyclotetramethylene tetranitramine (β-HMX) single crystals containing nanometer-scale spherical voids. Shock induced void collapse and subsequent hot spot formation as well as chemical reaction initiation are observed which depend on the void size and impact strength. For an impact velocity of 1 km s(-1) and a void radius of 4 nm, the void collapse process includes three stages; the dominant mechanism is the convergence of upstream molecules toward the centerline and the downstream surface of the void forming flowing molecules. Hot spot formation also undergoes three stages, and the principal mechanism is kinetic energy transforming to thermal energy due to the collision of flowing molecules on the downstream surface. The high temperature of the hot spot initiates a local chemical reaction, and the breakage of the N-NO2 bond plays the key role in the initial reaction mechanism. The impact strength and void size have noticeable effects on the shock dynamical process, resulting in a variation of the predominant mechanisms leading to void collapse and hot spot formation. Larger voids or stronger shocks result in more intense hot spots and, thus, more violent chemical reactions, promoting more reaction channels and generating more reaction products in a shorter duration. The reaction products are mainly concentrated in the developed hot spot, indicating that the chemical reactivity of the hmx crystal is greatly enhanced by void collapse. The detailed information derived from this study can aid a thorough understanding of the role of void collapse in hot spot formation and the chemical reaction initiation of explosives.

Toxicities of TNT and RDX to Terrestrial Plants in Five Soils with Contrasting Characteristics

Science.gov (United States)

2013-07-01

lettuce ( Lactuca sativa (L.)) and barley (Hordeum vulgare (L.)), respectively, at analytically determined soil concentrations up to and including 3320... sativa L.), Japanese millet (J. millet; Echinochloa crus-galli L. [Beauv.]), and perennial ryegrass (Lolium perenne L.) in five natural soils that...of the test. The test species in these studies were Medicago sativa (L.) var. Canada no. 1 (alfalfa), Echinochloa crus-galli (L.) P. Beauv. var

N-15 NMR study of the immobilization of 2,4- and 2,6-dinitrotoluene in aerobic compost

Science.gov (United States)

Thorn, K.A.; Pennington, J.C.; Kennedy, K.R.; Cox, L.G.; Hayes, C.A.; Porter, B.E.

2008-01-01

Large-scale aerobic windrow composting has been used to bioremediate washout lagoon soils contaminated with the explosives TNT (2,4,6- trinitrotoluene) and RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) at several sites within the United States. We previously used 15N NMR to investigate the reduction and binding of T15NT in aerobic bench -scale reactors simulating the conditions of windrow composting. These studies have been extended to 2,4-dinitrotoluene (2,4DNT) and 2,6-dinitrotoluene (2,6DNT), which, as impurities in TNT, are usually present wherever soils have been contaminated with TNT. Liquid-state 15N NMR analyses of laboratory reactions between 4-methyl-3-nitroaniline-15N, the major monoamine reduction product of 2,4DNT, and the Elliot soil humic acid, both in the presence and absence of horseradish peroxidase, indicated that the amine underwent covalent binding with quinone and other carbonyl groups in the soil humic acid to form both heterocyclic and non-heterocyclic condensation products. Liquid-state 15N NMR analyses of the methanol extracts of 20 day aerobic bench-scale composts of 2,4-di-15N-nitrotoluene and 2,6-di-15N-nitrotoluene revealed the presence of nitrite and monoamine, but not diamine, reduction products, indicating the occurrence of both dioxygenase enzyme and reductive degradation pathways. Solid-state CP/MAS 15N NMR analyses of the whole composts, however, suggested that reduction to monoamines followed by covalent binding of the amines to organic matter was the predominant pathway. ?? 2008 American Chemical Society.

Effect of Simulated Weathering and Aging of TNT in Amended Sandy Loam Soil on Toxicity to the Enchytraeid Worm, Enchytreaeus Crypticus

Science.gov (United States)

2006-05-01

high bioavailability of organic compounds. However, amended SSL soil was analyzed for presence of metabolic transformation products from nitroaromatic...Phillips, C.; Checkai, R. 1999. Comparison of malathion toxicity using enchytraeid reproduction test and earthworm toxicity test in different soil ...OF TNT IN AMENDED SANDY LOAM SOIL ON TOXICITY TO THE ENCHYTRAEID WORM, ENCHYTRAEUS CRYPTICUS Roman G. Kuperman Ronald T. Checkai Michael Simini

Oblique impact and friction of HMX and/or TATB-based PBXs

Science.gov (United States)

Picart, Didier; Junqua-Moullet, Alexandra

2017-06-01

Transportation, handling, vibrations can lead to moderate compressive but dynamic loadings requiring the characterization of the safety of PBXs submitted to such scenarios. Knowing that ignition can occur at a lower critical height during a fall on an inclined surface than a normal impact, the attention is focused in this paper on the heating due to the friction between PBXs and surfaces. A lot of experiments have been made using free-falling samples in vertical drop configurations on inclined targets or pendulum (skid) drop configurations (Green et al. 1971; Randolph et al. 1976). Data obtained on our HMX and/or TATB-based plastic-bonded explosives using pendulum drop configurations will be detailed. Evaluation of the heating due to friction requires the determination of the tangential projectile/target relative displacement and the contact pressure. The pressure is related to the normal force during the impact and the evolving contact surface, the latter being evaluated using a series of normal impacts. The aim of our paper is to compare the experimental diameter of the contact zones to (i) the classical Hertz's theory of contacting elastic solids and (ii) a spring-mass description of the impact. Data and models are then used to evaluate the increase of the temperature at the projectile/target interface for our explosives. We highlight the experimental bias which has already been attributed to the grits used to mimic the roughness of the surfaces.

Antenna loading and electron heating experiments of ICRF wave in TNT-A tokamak

International Nuclear Information System (INIS)

Shinohara, Shunjiro; Asakura, Nobuyuki; Naito, Masahiro; Miyamoto, Kenro

1984-01-01

Antenna loading resistance and electron heating effects of ICRF wave were investigated in TNT-A tokamak. Lodaing resistance increased with the mean plasma density and decreased with the input power. The effect of the distance between the plasma and antenna surface on loading resistance was studied and had good agreements with the calculated results. The increase in the soft Xray emissivity was larger in the presence of ion-ion hybrid and/or ion cyclotron resonance layer in the plasma than that in the absence of them. With the absorbed power up to two times of the ohmic power, the central electron temperature increased by 20%, the soft Xray emissivity increased by 80% and the mean plasma density decreased by 10%, while the total radiation loss increased slightly (by 15%). (author)

Geochemical evidence of groundwater flow paths and the fate and transport of constituents of concern in the alluvial aquifer at Fort Wingate Depot Activity, New Mexico, 2009

Science.gov (United States)

Robertson, Andrew J.; Henry, David W.; Langman, Jeffery B.

2013-01-01

accidental spill of perchlorate was spatially limited, and that dilution is the primary attenuation process for these constituents. The explosive concentrations of the nitramine 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) and the oxidizer perchlorate both support that determination. Unlike RDX and perchlorate, there were no detectable concentrations of trinitrotoluene (TNT) in the aquifer. Based on the chemical nature of TNT and the redox conditions found in the aquifer, it is interpreted that TNT is lost to irreversible sorption and aerobic degradation. Nitrate was ubiquitous in the alluvial groundwater in October 2009. The nitrate concentrations in wells associated with the explosives’ groundwater flow path indicate attenuation primarily through dilution, similar to that of RDX. The origin of nitrate concentrations in the wells located in the Administration Area is uncertain but may have resulted from the leakage of aging clay sewage pipes that service most of the structures within that area or as a relic of a former hydrologic regime in which water from the washout operation migrated across a broader area. Sufficient data do not exist to definitively identify the location(s) of water discharge in this area, but transpiration from near the Administration Area is supported by the geochemical concentrations.

Transport in aluminized RDX under shock compression explored using molecular dynamics simulations

International Nuclear Information System (INIS)

Losada, M; Chaudhuri, S

2014-01-01

Shock response of energetic materials is controlled by a combination of mechanical response, thermal, transport, and chemical properties. How these properties interplay in condensed-phase energetic materials is of fundamental interest for improving predictive capabilities. Due to unknown nature of chemistry during the evolution and growth of high-temperature regions within the energetic material (so called hot spots), the connection between reactive and unreactive equations of state contain a high degree of empiricism. In particular, chemistry in materials with high degree of heterogeneity such as aluminized HE is of interest. In order to identify shock compression states and transport properties in high-pressure/temperature (HP-HT) conditions, we use molecular dynamics (MD) simulations in conjunction with the multi-scale shock technique (MSST). Mean square displacement calculations enabled us to track the diffusivity of stable gas products. Among decomposition products, H 2 O and CO 2 are found to be the dominant diffusing species under compression conditions. Heat transport and diffusion rates in decomposed RDX are compared and the comparison shows that around 2000 K, transport can be a major contribution during propagation of the reaction front.

Capacities of Candidate Herbaceous Plants for Phytoremediation of Soil-based TNT and RDX on Ranges

Science.gov (United States)

2008-09-01

installations and distribution of Sida spinosa...Lehi, UT • Forb seeds from three vendors as follows: redroot pigweed (Amaran- thus retroflexus), morning glory (Ipomoea lacunosa), and prickly sida ... Sida spinosa) from Azlin Seed Service, Leland, MS; common milk- weed (Asclepias syriaca) from Prairiemoon Nursery, Winona, WI; common purslane

Capacities of Candidate Herbaceous Plants for Phytoremediation of Soil-based TNT and RDX on Ranges

National Research Council Canada - National Science Library

Best, Elly P; Smith, Thomas; Hagen, Frank L; Dawson, Jeffrey O; Torrey, Alan J

2008-01-01

.... In these experiments, plants were exposed for periods ranging from 55 to 83 days in the greenhouse, biomass and evapotranspiration characteristics were determined, and residues of explosives' parent...

Genetic and Biochemical Basis for the Transformation of Energetic Materials (RDX, TNT, DNTs) by Plants

Science.gov (United States)

2007-04-01

cultivating them from seeds as described in the previous section. Seedlings were grown at 25ºC under light at 100 rpm for seven days, following which three...detector. The ratio of the mobile phase of HPLC to Ultima Flo M cocktail was 1: 2. 2.3. Cultivation of plants Wild-type Arabidopsis thaliana...Organic toxicants and plants. Ecotoxicology and Environmental Safety 47:1-26 Larson SL, Jones RP, Escalon L, Parker D (1999) Classification of explosives

A Multipathway Model for High Explosives and Barium Transport Using GoldSim

Science.gov (United States)

Newman, B. D.; Hickmott, D. D.; Keating, E. H.; Robinson, B. A.; Gard, M. O.

2002-05-01

Outfalls from High Explosives (HE) production sites at Los Alamos National Laboratory (LANL) discharged RDX, TNT, HMX, and barium contaminated waters onto a mesa /canyon system on the western edge of the Pajarito Plateau from 1944 to 1996. HE concentrations in surface soils ranged to over 20 wt.%, and HE in waters range to over 800 ug/L. HE in water is present in springs, surface waters, alluvial waters and deep perched (> 700 ft. depth) and possibly regional (> 1200 ft depth) groundwaters. Barium concentrations range to over 4 wt.% in sediments, and to over 5000 ug/L in spring and alluvial waters. Because of the size of contaminant inventories and observations of HE in the perched zone and possibly deeper, there has been concern that there may be a long-term risk at a downgradient drinking water supply well. To address this concern, a GoldSim multipathway model was developed to simulate transport of HE and barium from source areas to the supply well. The objectives of the modeling effort were to generate a preliminary assessment of potential concentrations at the supply well and to identify any model components/parameters that require additional characterization based on model sensitivity and uncertainty. The model evaluates two main source areas, one is controlled by flow through the mesa vadose zone, and the other by flow through the canyon vadose zone. The two vadose zone modules feed into a saturated zone module that terminates at a pumping well (drinking water) module. The hydrogeology of the site is extremely complex and includes a heterogeneous, unfractured/fractured tuff vadose zone geology, ponds, springs, alluvial aquifers, a perennial stream reach, and two deep aquifers. Because of this complexity, and limited characterization and contaminant inventory information, we used a stochastic approach to quantitatively represent model/parameter uncertainties. Model parameters were developed using a variety of information including flow and transport modeling

High Density, Insensitive Oxidizer With RDX Performance Final Report CRADA No. TC02178.0

Energy Technology Data Exchange (ETDEWEB)

Pagoria, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Preda, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2017-08-25

This was a collaborative effort between Lawrence Livermore National Security, LLC as manager and operator of Lawrence Livermore National Laboratory (LLNL) and Physical Sciences, Inc. (PSI), to develop a synthesis and evaluate a novel high density, insensitive oxidizer with RDX performance. This CRADA resulted from the award of a Phase I STTR ("STTR") from DOD. In recent years, the synthesis of new energetic heterocyclic compounds to replace the energetic materials currently in the stockpile has received a great amount of attention. The Office of the Secretary of Defense has identified that there is a need to incorporate new energetic materials in current and future weapon systems in an effort to increase performance and decrease sensitivity. For many of the future weapon systems, incorporation of energetic compounds currently in the stockpile will not provide the desired performance and sensitivity goals. The success of this CRADA may lead to a Phase I option STTR from DOD and to a Phase II STTR from DOD. The goal of this CRADA was to produce and test a novel oxidizer, 2,5,8-trinitroheptazine (TNH).

A level set approach for shock-induced α-γ phase transition of RDX

Science.gov (United States)

Josyula, Kartik; Rahul; De, Suvranu

2018-02-01

We present a thermodynamically consistent level sets approach based on regularization energy functional which can be directly incorporated into a Galerkin finite element framework to model interface motion. The regularization energy leads to a diffusive form of flux that is embedded within the level sets evolution equation which maintains the signed distance property of the level set function. The scheme is shown to compare well with the velocity extension method in capturing the interface position. The proposed level sets approach is employed to study the α-γphase transformation in RDX single crystal shocked along the (100) plane. Example problems in one and three dimensions are presented. We observe smooth evolution of the phase interface along the shock direction in both models. There is no diffusion of the interface during the zero level set evolution in the three dimensional model. The level sets approach is shown to capture the characteristics of the shock-induced α-γ phase transformation such as stress relaxation behind the phase interface and the finite time required for the phase transformation to complete. The regularization energy based level sets approach is efficient, robust, and easy to implement.

Fabrication of Graded Porous and Skin-Core Structure RDX-Based Propellants via Supercritical CO2 Concentration Profile

Science.gov (United States)

Yang, Weitao; Li, Yuxiang; Ying, Sanjiu

2015-04-01

A fabrication process to produce graded porous and skin-core structure propellants via supercritical CO2 concentration profile is reported in this article. It utilizes a partial gas saturation technique to obtain nonequilibrium gas concentration profiles in propellants. Once foamed, the propellant obtains a graded porous or skin-pore structure. This fabrication method was studied with RDX(Hexogen)-based propellant under an SC-CO2 saturation condition. The principle was analyzed and the one-dimensional diffusion model was employed to estimate the gas diffusion coefficient and to predict the gas concentration profiles inside the propellant. Scanning electron microscopy images were used to analyze the effects of partial saturation on the inner structure. The results also suggested that the sorption time and desorption time played an important role in gas profile generation and controlled the inner structure of propellants.

An Evaluation of the Environmental Fate and behavior of Munitions Materiel (TNT, RDX) in Soil and Plant Systems. Environmental Fate and behavior of TNT

Science.gov (United States)

1989-08-01

for 48 I. The soil extracts were filtered through a 0.22-lim Nylon 66 filter ( Alltech Associates, Deerfield, Illinois), and the volume was then... advantages over the analysis of stem tissue. Paramount among these is that stem exudate contains only xylem transport products, or those metabolites being...transported 3 from root to shoot tissues, whereas stem tissue contains both transport products and storage forms of xenobiotics. Additional advantages

Model remediation of contaminated sites as illustrated by the example of the TNT-remediation project Stadtallendorf, Hessen, Germany. Part 1: Final report; Part 2: Documentation and balancing of the measures; Part 3: Documentation of citizens' participation and public relations activities in Stadtallendorf; Modellhafte Sanierung von Altlasten am Beispiel des TNT-Sanierungsprojektes Stadtallendorf/Hessen. T. 1: Abschlussbericht. T. 2: Dokumentation und Bilanzierung von Auswirkungen der Sanierung. T. 3: Dokumentation der Buergerbeteiligung und Oeffentlichkeitsarbeit in Stadtallendorf

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-07-01

The project comprised the following stages: 1. Development of a technology for purification of soils contaminated with explosives. The process comprised soil washing, hot steam treatment, and thermal treatment of residues; 2. Projecting, construction and two years of operation of a soil purification plant with a rated throughput of 20 t/h and a total throughput of 130,000 t; 3. Remediation of two representative sites on DAG terrain (TNT production chain and filling stations); 4. Verification of the findings in an accompanying scientific programme. The site under investigation was formerly occupied by the Dynamit AG (DAG) Stadtallendorf, where TNT, contaminated waste water and acids were produced, and contamination levels were high in several areas. Today, the area is a residential area. In addition to the investigations described here, the waste water discharge system of the DAG was modernized. [German] Das FuE-Vorhaben Stadtallendorf wurde mit folgender Zielsetzung begonnen: (1) Entwicklung einer geeigneten und moeglichst umweltvertraeglichen Technik zur Reinigung von Boeden mit sprengstoffspezifischen Kontaminationen; hierzu wurde in Anlehnung an die Ausschreibung des Bundes ein kombiniertes Bodenbehandlungsverfahren vorgesehen, das aus folgenden Komponenten bestand: - Bodenwaesche, - Heissdampfbehandlung, - Thermische Reststoffbehandlung. (2) Planung, Bau und zweijaehriger Betrieb einer entsprechenden grosstechnischen Bodenreinigungsanlage (Nenndurchsatz von 20 t/Stunde; Gesamtdurchsatz 130.000 t). (3) Bodensanierung von zwei repraesentativen Arealen im DAG-Gelaende (TNT-Produktionskette und Fuellstellenbetrieb). (4) Absicherung der Ergebnisse in einem wissenschaftlichen Begleitprogramm. Gegenstand der Phase 2 des Vorhabens war der vollstaendige Prozess der Planung und Umsetzung der Sanierung eines (Teils eines) Planungsraumes des Ruestungsaltstandortes Dynamit AG (DAG) Stadtallendorf. Es handelte sich dabei um einen Bereich, der als Standort fuer TNT

Examining the effects of microstructure and loading on the shock initiation of HMX with mesoscale simulations

Science.gov (United States)

Springer, H. Keo; Tarver, Craig; Bastea, Sorin

2015-06-01

We perform reactive mesoscale simulations to study shock initiation in HMX over a range of pore morphologies and sizes, porosities, and loading conditions in order to improve our understanding of structure-performance relationships. These relationships are important because they guide the development of advanced macroscale models incorporating hot spot mechanisms and the optimization of novel energetic material microstructures. Mesoscale simulations are performed using the multiphysics hydrocode, ALE3D. Spherical, elliptical, polygonal, and crack-like pore geometries 0.1, 1, 10, and 100 microns in size and 2, 5, 10, and 14% porosity are explored. Loading conditions are realized with shock pressures of 6, 10, 20, 38, and 50 GPa. A Cheetah-based tabular model, including temperature-dependent heat capacity, is used for the unreacted and the product equation-of-state. Also, in-line Cheetah is used to probe chemical species evolution. The influence of microstructure and shock loading on shock-to-detonation-transition run distance, reaction rate and product gas species evolution are discussed. This work performed under the auspices of the U.S. DOE by LLNL under Contract DE-AC52-07NA27344. This work is funded by the Joint DoD-DOE Munitions Program.

Toxicities of TNT and RDX to the Earthworm Eisenia fetida in Five Soils with Contrasting Characteristics

Science.gov (United States)

2013-05-01

to prevent photolysis of the EM. Each soil treatment sample was then transferred into a fluorocarbon-coated, high-density polyethylene container and...and abiotic processes under anaerobic and aerobic conditions (Sunahara et al., 2001). A number of soil-borne bacteria and fungi are known to transform

Spectral Characterization of RDX, ETN, PETN, TATP, HMTD, HMX, and C-4 in the Mid-Infrared Region

Science.gov (United States)

2014-04-01

Germany, 1996. 12. Bertie, J.E. and Keefe , C.D. “Infrared intensities of liquids XXIV: Optical constants of liquid benzene-h6 at 25°C extended to...Bertie, J.E.; Apelblat, Y.; Keefe , C.D. “Infrared intensities of liquids XXV: Optical constants of liquid toluene at 25°C between 4800 and 400 cm−1

CMR of EEX? Van samenloop, litispendentie en het vrij verkeer van beslissingen in Europa. Hof van Justitie EU 4 mei 2010, zaak C-533/08 (TNT Express/AXA)

NARCIS (Netherlands)

M.A.I.H. Hoeks (Marian)

2011-01-01

textabstractAbstract The seed from which the problem sprouted in the TNT-AXA case is the fact that the CMR, an international road carriage convention, refers to national law in Article 29 CMR. This Article determines that if the CMR carrier has caused damage to the cargo ‘by such default on his

High pressure-temperature polymorphism of 1,1-diamino-2,2-dinitroethylene

Science.gov (United States)

Bishop, M. M.; Chellappa, R. S.; Liu, Z.; Preston, D. N.; Sandstrom, M. M.; Dattelbaum, D. M.; Vohra, Y. K.; Velisavljevic, N.

2014-05-01

1,1-diamino-2,2-dinitroethylene (FOX-7) is a low sensitivity energetic material with performance comparable to commonly used secondary explosives such as RDX and HMX. At ambient pressure, FOX-7 exhibits complex polymorphism with at least three structurally distinct phases (α, β, and γ). In this study, we have investigated the high pressure-temperature stability of FOX-7 polymorphs using synchrotron mid-infrared (MIR) spectroscopy. At ambient pressure, our MIR spectra and corresponding differential scanning calorimetry (DSC) measurements confirmed the known α → β (~110 °C) and α → β (~160 °C) structural phase transitions; as well as, indicated an additional transition γ → (~210 °C), with the δ phase being stable up to ~251 °C prior to decomposition. In situ MIR spectra obtained during isobaric heating at 0.9 GPa, revealed a potential α → β transition that could occur as early as 180 °C, while β → β+δ phase transition shifted to ~300 °C with suppression of γ phase. Decomposition was observed slightly above 325 °C at 0.9 GPa.

Integrated Data Collection Analysis (IDCA) Program - Statistical Analysis of RDX Standard Data Sets

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorensen, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Phillips, Jason J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Shelley, Timothy J. [Air Force Research Lab. (AFRL), Tyndall AFB, FL (United States); Reyes, Jose A. [Applied Research Associates, Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2015-10-30

The Integrated Data Collection Analysis (IDCA) program is conducting a Proficiency Test for Small- Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are statistical analyses of the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of the RDX Type II Class 5 standard. The material was tested as a well-characterized standard several times during the proficiency study to assess differences among participants and the range of results that may arise for well-behaved explosive materials. The analyses show that there are detectable differences among the results from IDCA participants. While these differences are statistically significant, most of them can be disregarded for comparison purposes to assess potential variability when laboratories attempt to measure identical samples using methods assumed to be nominally the same. The results presented in this report include the average sensitivity results for the IDCA participants and the ranges of values obtained. The ranges represent variation about the mean values of the tests of between 26% and 42%. The magnitude of this variation is attributed to differences in operator, method, and environment as well as the use of different instruments that are also of varying age. The results appear to be a good representation of the broader safety testing community based on the range of methods, instruments, and environments included in the IDCA Proficiency Test.

Development of the QA/QC Procedures for a Neutron Interrogation System

Energy Technology Data Exchange (ETDEWEB)

Obhodas, Jasmina; Sudac, Davorin; Valkovic, Vladivoj [Ruder Boskovic Institute, 10000 Zagreb (Croatia)

2015-07-01

In order to perform QA/QC procedures for a system dedicated to the neutron interrogation of objects for the presence of threat materials one needs to perform measurements of reference materials (RM) having the same (or similar) atomic ratios as real materials. It is well known that explosives, drugs, and various other benign materials, contain chemical elements such as hydrogen, oxygen, carbon and nitrogen in distinctly different quantities. For example, a high carbon-to-oxygen ratio (C/O) is characteristic of drugs. Explosives can be differentiated by measurement of both C/O and nitrogen-to-oxygen (N/O) ratios. The C/N ratio of the chemical warfare agents, coupled with the measurement of elements such as fluorine and phosphorus, clearly differentiate them from the conventional explosives. Correlations between theoretical values and experimental results obtained in laboratory conditions for C/O and N/C ratios of simulants of hexogen (RDX), TNT, DLM2, TATP, cocaine, heroin, yperite, tetranitromethane, peroxide methylethyl-ketone, nitromethane and ethyleneglycol dinitrate are presented. (authors)

Acute and Chronic Toxicities of TNT and RDX to the Enchytraeid Worm, Enchytraeus crypticus, in Natural Soils

Science.gov (United States)

2012-11-01

Checkai, R. Comparison of Malathion Toxicity Using Enchytraeid Reproduction Test and Earthworm Toxicity Test in Different Soil Types. Pedobiologia...Russow, R.; Richnow, H.H.; Kastner, M. Fate and Metabolism of [ 15 N]2,4,6-Trinitrotoluene in Soil . Environ. Toxicol. Chem. 2004, 23, pp 1852–1860...ENCHYTRAEUS CRYPTICUS, IN NATURAL SOILS ECBC-TR-981 Roman G. Kuperman Ronald T. Checkai Michael Simini Carlton T. Phillips Jan E. Kolakowski Carl

Shock-induced transformations in crystalline RDX: a uniaxial constant-stress Hugoniostat molecular dynamics simulation study.

Science.gov (United States)

Bedrov, Dmitry; Hooper, Justin B; Smith, Grant D; Sewell, Thomas D

2009-07-21

Molecular dynamics (MD) simulations of uniaxial shock compression along the [100] and [001] directions in the alpha polymorph of hexahydro-1,3,5-trinitro-1,3,5-triazine (alpha-RDX) have been conducted over a wide range of shock pressures using the uniaxial constant stress Hugoniostat method [Ravelo et al., Phys. Rev. B 70, 014103 (2004)]. We demonstrate that the Hugoniostat method is suitable for studying shock compression in atomic-scale models of energetic materials without the necessity to consider the extremely large simulation cells required for an explicit shock wave simulation. Specifically, direct comparison of results obtained using the Hugoniostat approach to those reported by Thompson and co-workers [Phys. Rev. B 78, 014107 (2008)] based on large-scale MD simulations of shocks using the shock front absorbing boundary condition (SFABC) approach indicates that Hugoniostat simulations of systems containing several thousand molecules reproduced the salient features observed in the SFABC simulations involving roughly a quarter-million molecules, namely, nucleation and growth of nanoscale shear bands for shocks propagating along the [100] direction and the polymorphic alpha-gamma phase transition for shocks directed along the [001] direction. The Hugoniostat simulations yielded predictions of the Hugoniot elastic limit for the [100] shock direction consistent with SFABC simulation results.

Case note: ECJ (Case no. C-533/08, TNT Express Nederland BV. v. AXA Versicherung AG: The changing status of private international law treaties of the Member States in relation to regulation no. 44/2001)

NARCIS (Netherlands)

Kuijper, P.J.

2011-01-01

Case C-533/08, the so-called TNT case, is concerned with the interpretation of Article 71 of Regulation No. 44/2001 on jurisdiction and the recognition and enforcement of judgments in civil and commercial matters (hereinafter ‘Brussels Regulation’) and with the relation between this Regulation and

Performance evaluation of granular activated carbon system at Pantex: Rapid small-scale column tests to simulate removal of high explosives from contaminated groundwater

Energy Technology Data Exchange (ETDEWEB)

Henke, J.L.; Speitel, G.E. [Univ. of Texas, Austin, TX (United States). Dept. of Civil Engineering

1998-08-01

A granular activated carbon (GAC) system is now in operation at Pantex to treat groundwater from the perched aquifer that is contaminated with high explosives. The main chemicals of concern are RDX and HMX. The system consists of two GAC columns in series. Each column is charged with 10,000 pounds of Northwestern LB-830 GAC. At the design flow rate of 325 gpm, the hydraulic loading is 6.47 gpm/ft{sup 2}, and the empty bed contact time is 8.2 minutes per column. Currently, the system is operating at less than 10% of its design flow rate, although flow rate increases are expected in the relatively near future. This study had several objectives: Estimate the service life of the GAC now in use at Pantex; Screen several GACs to provide a recommendation on the best GAC for use at Pantex when the current GAC is exhausted and is replaced; Determine the extent to which natural organic matter in the Pantex groundwater fouls GAC adsorption sites, thereby decreasing the adsorption capacity for high explosives; and Determine if computer simulation models could match the experimental results, thereby providing another tool to follow system performance.

Fate of CL-20 in sandy soils: Degradation products as potential markers of natural attenuation

International Nuclear Information System (INIS)

Monteil-Rivera, Fanny; Halasz, Annamaria; Manno, Dominic; Kuperman, Roman G.; Thiboutot, Sonia; Ampleman, Guy; Hawari, Jalal

2009-01-01

Hexanitrohexaazaisowurtzitane (CL-20) is an emerging explosive that may replace the currently used explosives such as RDX and HMX, but little is known about its fate in soil. The present study was conducted to determine degradation products of CL-20 in two sandy soils under abiotic and biotic anaerobic conditions. Biotic degradation was prevalent in the slightly acidic VT soil, which contained a greater organic C content, while the slightly alkaline SAC soil favored hydrolysis. CL-20 degradation was accompanied by the formation of formate, glyoxal, nitrite, ammonium, and nitrous oxide. Biotic degradation of CL-20 occurred through the formation of its denitrohydrogenated derivative (m/z 393 Da) while hydrolysis occurred through the formation of a ring cleavage product (m/z 156 Da) that was tentatively identified as CH 2 =N-C(=N-NO 2 )-CH=N-CHO or its isomer N(NO 2 )=CH-CH=N-CO-CH=NH. Due to their chemical specificity, these two intermediates may be considered as markers of in situ attenuation of CL-20 in soil. - Two key intermediates of CL-20 degradation are potential markers of its natural attenuation in soil

High pressure-temperature polymorphism of 1,1-diamino-2,2-dinitroethylene

International Nuclear Information System (INIS)

Bishop, M M; Dattelbaum, D M; Velisavljevic, N; Chellappa, R S; Liu, Z; Preston, D N; Sandstrom, M M; Vohra, Y K

2014-01-01

1,1-diamino-2,2-dinitroethylene (FOX-7) is a low sensitivity energetic material with performance comparable to commonly used secondary explosives such as RDX and HMX. At ambient pressure, FOX-7 exhibits complex polymorphism with at least three structurally distinct phases (α, β, and γ). In this study, we have investigated the high pressure-temperature stability of FOX-7 polymorphs using synchrotron mid-infrared (MIR) spectroscopy. At ambient pressure, our MIR spectra and corresponding differential scanning calorimetry (DSC) measurements confirmed the known α → β (∼110 °C) and α → β (∼160 °C) structural phase transitions; as well as, indicated an additional transition γ → (∼210 °C), with the δ phase being stable up to ∼251 °C prior to decomposition. In situ MIR spectra obtained during isobaric heating at 0.9 GPa, revealed a potential α → β transition that could occur as early as 180 °C, while β → β+δ phase transition shifted to ∼300 °C with suppression of γ phase. Decomposition was observed slightly above 325 °C at 0.9 GPa.

Performance evaluation of granular activated carbon system at Pantex: Rapid small-scale column tests to simulate removal of high explosives from contaminated groundwater

International Nuclear Information System (INIS)

Henke, J.L.; Speitel, G.E.

1998-08-01

A granular activated carbon (GAC) system is now in operation at Pantex to treat groundwater from the perched aquifer that is contaminated with high explosives. The main chemicals of concern are RDX and HMX. The system consists of two GAC columns in series. Each column is charged with 10,000 pounds of Northwestern LB-830 GAC. At the design flow rate of 325 gpm, the hydraulic loading is 6.47 gpm/ft 2 , and the empty bed contact time is 8.2 minutes per column. Currently, the system is operating at less than 10% of its design flow rate, although flow rate increases are expected in the relatively near future. This study had several objectives: Estimate the service life of the GAC now in use at Pantex; Screen several GACs to provide a recommendation on the best GAC for use at Pantex when the current GAC is exhausted and is replaced; Determine the extent to which natural organic matter in the Pantex groundwater fouls GAC adsorption sites, thereby decreasing the adsorption capacity for high explosives; and Determine if computer simulation models could match the experimental results, thereby providing another tool to follow system performance

Ecotoxicological evaluation of in situ bioremediation of soils contaminated by the explosive 2,4,6-trinitrotoluene (TNT)

International Nuclear Information System (INIS)

Frische, Tobias

2003-01-01

The luminescent bacteria assay, using soil leachates, was the most sensitive toxicity indicator. - To evaluate the environmental relevance of in situ bioremediation of contaminated soils, effective and reliable monitoring approaches are of special importance. The presented study was conducted as part of a research project investigating in situ bioremediation of topsoils contaminated by the explosive 2,4,6-trinitrotoluene (TNT). Changes in soil toxicity within different experimental fields at a former ordnance factory were evaluated using a battery of five bioassays (plant growth, Collembola reproduction, soil respiration, luminescent bacteria acute toxicity and mutagenicity test) in combination to chemical contaminant analysis. Resulting data reveal clear differences in sensitivities between methods with the luminescent bacteria assay performed with soil leachates as most sensitive toxicity indicator. Complete test battery results are presented in so-called soil toxicity profiles to visualise and facilitate the interpretation of data. Both biological and chemical monitoring results indicate a reduction of soil toxicity within 17 months of remediation

Gas gun experiments and numerical simulations on the HMX-based explosive PBX 9501 in the overdriven 30 to 120 GPa pressure regime

Science.gov (United States)

Pittman, E. R.; Gustavsen, R. L.; Hagelberg, C. R.; Schmidt, J. H.

2017-06-01

The focus of this set of experiments is the development of data on the Hugoniot for the overdriven products equation of state (EOS) of PBX 9501 (95 weight % HMX, 5 weight % plastic binder) and to extend data from which current computational EOS models draw. This series of shots was conducted using the two-stage gas-guns at Los Alamos and aimed to gather data in the 30 to 120 GPa pressure regime. Experiments were simulated using FLAG, a Langrangian multiphysics code, using a one-dimensional setup which employs the Wescott Stewart Davis (WSD) reactive burn model. Prior to this study, data did not extend above 90 GPa, so the new data allowed the model to be re-evaluated. A comparison of the simulations with the experimental data shows that the model fits well below 80 GPa. However, the model did not fall within the error bars of the data for higher pressures. This is an indication that the PBX 9501 overdriven EOS products model could be modified to better match the data.

Standoff laser-induced thermal emission of explosives

Science.gov (United States)

Galán-Freyle, Nataly Y.; Pacheco-Londoño, Leonardo C.; Figueroa-Navedo, Amanda; Hernandez-Rivera, Samuel P.

2013-05-01

A laser mediated methodology for remote thermal excitation of analytes followed by standoff IR detection is proposed. The goal of this study was to determine the feasibility of using laser induced thermal emission (LITE) from vibrationally excited explosives residues deposited on surfaces to detect explosives remotely. Telescope based FT-IR spectral measurements were carried out to examine substrates containing trace amounts of threat compounds used in explosive devices. The highly energetic materials (HEM) used were PETN, TATP, RDX, TNT, DNT and ammonium nitrate with concentrations from 5 to 200 μg/cm2. Target substrates of various thicknesses were remotely heated using a high power CO2 laser, and their mid-infrared (MIR) thermally stimulated emission spectra were recorded. The telescope was configured from reflective optical elements in order to minimize emission losses in the MIR frequencies and to provide optimum overall performance. Spectral replicas were acquired at a distance of 4 m with an FT-IR interferometer at 4 cm- 1 resolution and 10 scans. Laser power was varied from 4-36 W at radiation exposure times of 10, 20, 30 and 60 s. CO2 laser powers were adjusted to improve the detection and identification of the HEM samples. The advantages of increasing the thermal emission were easily observed in the results. Signal intensities were proportional to the thickness of the coated surface (a function of the surface concentration), as well as the laser power and laser exposure time. For samples of RDX and PETN, varying the power and time of induction of the laser, the calculated low limit of detections were 2 and 1 μg/cm2, respectively.

Short pulse duration shock initiation experiments plus ignition and growth modeling on Composition B

International Nuclear Information System (INIS)

May, Chadd M; Tarver, Craig M

2014-01-01

Composition B (63% RDX, 36% TNT, 1% wax) is still a widely used energetic material whose shock initiation characteristics are necessary to understand. It is now possible to shock initiate Composition B and other secondary explosives at diameters well below their characteristic failure diameters for unconfined self-sustaining detonation. This is done using very high velocity, very thin, small diameter flyer plates accelerated by electric or laser power sources. Recently experimental detonation versus failure to detonate threshold flyer velocity curves for Composition B using several Kapton TM flyer thicknesses and diameters were measured. Flyer plates with diameters of 2 mm successfully detonated Composition B, which has a nominal failure diameter of 4.3 mm. The shock pressures required for these initiations are greater than the Chapman-Jouguet (C-J) pressure in self-sustaining Composition B detonation waves. The initiation process is two-dimensional, because both rear and side rarefactions can affect the shocked Composition B reaction rates. The Ignition and Growth reactive flow model for Composition B is extended to yield accurate simulations of this new threshold velocity data for various flyer thicknesses.

First steps towards a validation of the new burnup and depletion code TNT

Energy Technology Data Exchange (ETDEWEB)

Herber, S.C.; Allelein, H.J. [RWTH Aachen (Germany). Inst. for Reactor Safety and Reactor Technology; Research Center Juelich (Germany). Inst. for Energy and Climate Research - Nuclear Waste Disposal and Reactor Safety (IEK-6); Friege, N. [RWTH Aachen (Germany). Inst. for Reactor Safety and Reactor Technology; Kasselmann, S. [Research Center Juelich (Germany). Inst. for Energy and Climate Research - Nuclear Waste Disposal and Reactor Safety (IEK-6)

2012-11-01

In the frame of the fusion of the core design calculation capabilities, represented by V.S.O.P., and the accident calculation capabilities, represented by MGT(-3D), the successor of the TINTE code, difficulties were observed in defining an interface between a program backbone and the ORIGEN code respectively the ORIGENJUEL code. The estimation of the effort of refactoring the ORIGEN code or to write a new burnup code from scratch, led to the decision that it would be more efficient writing a new code, which could benefit from existing programming and software engineering tools from the computer code side and which can use the latest knowledge of nuclear reactions, e.g. consider all documented reaction channels. Therefore a new code with an object-oriented approach was developed at IEK-6. Object-oriented programming is currently state of the art and provides mostly an improved extensibility and maintainability. The new code was named TNT which stands for Topological Nuclide Transformation, since the code makes use of the real topology of the nuclear reactions. Here we want to present some first validation results from code to code benchmarks with the codes ORIGEN V2.2 and FISPACT2005 and whenever possible analytical results also used for the comparison. The 2 reference codes were chosen due to their high reputation in the field of fission reactor analysis (ORIGEN) and fusion facilities (FISPACT). (orig.)

"Fooling fido"--chemical and behavioral studies of pseudo-explosive canine training aids.

Science.gov (United States)

Kranz, William D; Strange, Nicholas A; Goodpaster, John V

2014-12-01

Genuine explosive materials are traditionally employed in the training and testing of explosive-detecting canines so that they will respond reliably to these substances. However, challenges arising from the acquisition, storage, handling, and transportation of explosives have given rise to the development of "pseudo-explosive" training aids. These products attempt to emulate the odor of real explosives while remaining inert. Therefore, a canine trained on a pseudo-explosive should respond to its real-life analog. Similarly, a canine trained on an actual explosive should respond to the pseudo-explosive as if it was real. This research tested those assumptions with a focus on three explosives: single-base smokeless powder, 2,4,6-trinitrotoluene (TNT), and a RDX-based plastic explosive (Composition C-4). Using gas chromatography-mass spectrometry with solid phase microextraction as a pre-concentration technique, we determined that the volatile compounds given off by pseudo-explosive products consisted of various solvents, known additives from explosive formulations, and common impurities present in authentic explosives. For example, simulated smokeless powders emitted terpenes, 2,4-dinitrotoluene, diphenylamine, and ethyl centralite. Simulated TNT products emitted 2,4- and 2,6-dinitrotoluene. Simulated C-4 products emitted cyclohexanone, 2-ethyl-1-hexanol, and dimethyldinitrobutane. We also conducted tests to determine whether canines trained on pseudo-explosives are capable of alerting to genuine explosives and vice versa. The results show that canines trained on pseudo-explosives performed poorly at detecting all but the pseudo-explosives they are trained on. Similarly, canines trained on actual explosives performed poorly at detecting all but the actual explosives on which they were trained.

Electron shuttle-mediated biotransformation of hexahydro-1,3,5-trinitro-1,3,5-triazine adsorbed to granular activated carbon.

Science.gov (United States)

Millerick, Kayleigh; Drew, Scott R; Finneran, Kevin T

2013-08-06

Granular activated carbon (GAC) effectively removes hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) from groundwater but generates RDX-laden GAC that must be disposed of or regenerated. Batch reactors containing GAC to which RDX was preadsorbed were used in experiments to test the potential for adsorbed RDX reduction and daughter product formation using (i) chemically reduced anthrahydroquinone-2,6-disulfonate (AH2QDS), (ii) resting Geobacter metallireducens strain GS-15, and (iii) a combined system containing AQDS and GS-15. Approximately 97.0% of the adsorbed RDX was transformed in each of these experimental systems by 90 h. Chemically reduced AQDS (AH2QDS) transformed 99.2% of adsorbed RDX; formaldehyde was produced rapidly and was stoichiometric (3 mol HCHO per mol RDX). Geobacter metallireducens also reduced RDX with and without AQDS present. This is the first study to demonstrate biological transformation of RDX adsorbed to GAC. Formaldehyde increased and then decreased in biological systems, suggesting a previously unreported capacity for G. metallireducens to oxidize formaldehyde, which was confirmed with resting cell suspensions. These data suggest the masses of GAC waste currently produced by activated carbon at RDX remediation sites can be minimized, decreasing the carbon footprint of the treatment technology. Alternatively, this strategy may be used to develop a Bio-GAC system for ex situ RDX treatment.

Complement-Mediated Enhancement of Monocyte Adhesion to Endothelial Cells by HLA Antibodies, and Blockade by a Specific Inhibitor of the Classical Complement Cascade, TNT003

Science.gov (United States)

Valenzuela, Nicole M.; Thomas, Kimberly A.; Mulder, Arend; Parry, Graham C.; Panicker, Sandip; Reed, Elaine F.

2017-01-01

Background Antibody-mediated rejection (AMR) of most solid organs is characterized by evidence of complement activation and/or intragraft macrophages (C4d + and CD68+ biopsies). We previously demonstrated that crosslinking of HLA I by antibodies triggered endothelial activation and monocyte adhesion. We hypothesized that activation of the classical complement pathway at the endothelial cell surface by HLA antibodies would enhance monocyte adhesion through soluble split product generation, in parallel with direct endothelial activation downstream of HLA signaling. Methods Primary human aortic endothelial cells (HAEC) were stimulated with HLA class I antibodies in the presence of intact human serum complement. C3a and C5a generation, endothelial P-selectin expression, and adhesion of human primary and immortalized monocytes (Mono Mac 6) were measured. Alternatively, HAEC or monocytes were directly stimulated with purified C3a or C5a. Classical complement activation was inhibited by pretreatment of complement with an anti-C1s antibody (TNT003). Results Treatment of HAEC with HLA antibody and human complement increased the formation of C3a and C5a. Monocyte recruitment by human HLA antibodies was enhanced in the presence of intact human serum complement or purified C3a or C5a. Specific inhibition of the classical complement pathway using TNT003 or C1q-depleted serum significantly reduced adhesion of monocytes in the presence of human complement. Conclusions Despite persistent endothelial viability in the presence of HLA antibodies and complement, upstream complement anaphylatoxin production exacerbates endothelial exocytosis and leukocyte recruitment. Upstream inhibition of classical complement may be therapeutic to dampen mononuclear cell recruitment and endothelial activation characteristic of microvascular inflammation during AMR. PMID:28640789

New directions in the science and technology of advanced sheet explosive formulations and the key energetic materials used in the processing of sheet explosives: Emerging trends.

Science.gov (United States)

Talawar, M B; Jangid, S K; Nath, T; Sinha, R K; Asthana, S N

2015-12-30

This review presents the work carried out by the international community in the area of sheet explosive formulations and its applications in various systems. The sheet explosive is also named as PBXs and is a composite material in which solid explosive particles like RDX, HMX or PETN are dispersed in a polymeric matrix, forms a flexible material that can be rolled/cut into sheet form which can be applied to any complex contour. The designed sheet explosive must possess characteristic properties such as flexible, cuttable, water proof, easily initiable, and safe handling. The sheet explosives are being used for protecting tanks (ERA), light combat vehicle and futuristic infantry carrier vehicle from different attacking war heads etc. Besides, sheet explosives find wide applications in demolition of bridges, ships, cutting and metal cladding. This review also covers the aspects such as risks and hazard analysis during the processing of sheet explosive formulations, effect of ageing on sheet explosives, detection and analysis of sheet explosive ingredients and the R&D efforts of Indian researchers in the development of sheet explosive formulations. To the best of our knowledge, there has been no review article published in the literature in the area of sheet explosives. Copyright © 2015 Elsevier B.V. All rights reserved.

Thermal decomposition and reaction of confined explosives

International Nuclear Information System (INIS)

Catalano, E.; McGuire, R.; Lee, E.; Wrenn, E.; Ornellas, D.; Walton, J.

1976-01-01

Some new experiments designed to accurately determine the time interval required to produce a reactive event in confined explosives subjected to temperatures which will cause decomposition are described. Geometry and boundary conditions were both well defined so that these experiments on the rapid thermal decomposition of HE are amenable to predictive modelling. Experiments have been carried out on TNT, TATB and on two plastic-bonded HMX-based high explosives, LX-04 and LX-10. When the results of these experiments are plotted as the logarithm of the time to explosion versus 1/T K (Arrhenius plot), the curves produced are remarkably linear. This is in contradiction to the results obtained by an iterative solution of the Laplace equation for a system with a first order rate heat source. Such calculations produce plots which display considerable curvature. The experiments have also shown that the time to explosion is strongly influenced by the void volume in the containment vessel. Results of the experiments with calculations based on the heat flow equations coupled with first-order models of chemical decomposition are compared. The comparisons demonstrate the need for a more realistic reaction model

Fessibility Study on Nitrogen in Explosives using X-ray Photoelectron Spectroscopy: Chemical Fertilizer

International Nuclear Information System (INIS)

Dararutana, P.

2014-01-01

It was known that an explosive is defined as a material which contains a large amount of energy stored in chemical bonds. The energetic stability of gaseous products, and hence, their generation come from the strong bond formation of carbon (mono/di)oxide and (di)nitrogen. Consequently, most commercial explosives are contained -NO 2 , -ONO 2 and/or -NHNO 2 groups which when detonated release gases like the aforementioned ones, e.g., nitroglycerin, TNT, HMX, PETN, nitrocellulose, etc. It was revealed that the elemental compositions, especially N was found in most of the explosive and fertilizer. Chemical fertilizers that used as explosive stimulants were analyzed using X-ray photoelectron spectroscopy (XPS) and scanning electron microscope coupled with energy-dispersive X-ray fluorescence spectroscopy (SEM-EDS). XPS spectra showed relatively high amount of nitrogen (N) in the various samples, especially sample #6 and #7. In addition, the elemental analysis revealed the presence of trace elements. Explosives and fertilizers have differences in specific compositions. It can be concluded that these methods seem to be used as a fingerprint examination to identify various kinds of explosives and fertilizers.

Optimization of biological and instrumental detection of explosives and ignitable liquid residues including canines, SPME/ITMS and GC/MSn

Science.gov (United States)

Furton, Kenneth G.; Harper, Ross J.; Perr, Jeannette M.; Almirall, Jose R.

2003-09-01

A comprehensive study and comparison is underway using biological detectors and instrumental methods for the rapid detection of ignitable liquid residues (ILR) and high explosives. Headspace solid phase microextraction (SPME) has been demonstrated to be an effective sampling method helping to identify active odor signature chemicals used by detector dogs to locate forensic specimens as well as a rapid pre-concentration technique prior to instrumental detection. Common ignitable liquids and common military and industrial explosives have been studied including trinitrotoluene, tetryl, RDX, HMX, EGDN, PETN and nitroglycerine. This study focuses on identifying volatile odor signature chemicals present, which can be used to enhance the level and reliability of detection of ILR and explosives by canines and instrumental methods. While most instrumental methods currently in use focus on particles and on parent organic compounds, which are often involatile, characteristic volatile organics are generally also present and can be exploited to enhance detection particularly for well-concealed devices. Specific examples include the volatile odor chemicals 2-ethyl-1-hexanol and cyclohexanone, which are readily available in the headspace of the high explosive composition C-4; whereas, the active chemical cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX) is not. The analysis and identification of these headspace 'fingerprint' organics is followed by double-blind dog trials of the individual components using certified teams in an attempt to isolate and understand the target compounds to which dogs are sensitive. Studies to compare commonly used training aids with the actual target explosive have also been undertaken to determine their suitability and effectiveness. The optimization of solid phase microextraction (SPME) combined with ion trap mobility spectrometry (ITMS) and gas chromatography/mass spectrometry/mass spectrometry (GC/MSn) is detailed including interface development

Deuterium isotope effects in condensed-phase thermochemical decomposition reactions of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine

International Nuclear Information System (INIS)

Shackelford, S.A.; Coolidge, M.B.; Goshgarian, B.B.; Loving, B.A.; Rogers, R.N.; Janney, J.L.; Ebinger, M.H.

1985-01-01

The deuterium isotope effect was applied to condensed-phase thermochemical reactions of HMX and HMX-d 8 by using isothermal techniques. Dissimilar deuterium isotope effects revealed a mechanistic dependence of HMX upon different physical states which may singularly predominate in a specific type of thermal event. Solid-state HMX thermochemical decomposition produces a primary deuterium isotope effect (DIE), indicating that covalent C-H bond rupture is the rate-controlling step in this phase. An apparent inverse DIE is displayed by the mixed melt phase and can be attributed to C-H bond contraction during a weakening of molecular lattice forces as the solid HMX liquefies. The liquid-state decomposition rate appears to be controlled by ring C-N bond cleavage as evidenced by a secondary DIE and higher molecular weight products. These results reveal a dependence of the HMX decomposition process on physical state and lead to a broader mechanistic interpretation which explains the seemingly contradictory data found in current literature reviews. 33 references, 9 figures, 5 tables

Infrared photothermal imaging of trace explosives on relevant substrates

Science.gov (United States)

Kendziora, Christopher A.; Furstenberg, Robert; Papantonakis, Michael; Nguyen, Viet; Borchert, James; Byers, Jeff; McGill, R. Andrew

2013-06-01

We are developing a technique for the stand-off detection of trace explosives on relevant substrate surfaces using photo-thermal infrared (IR) imaging spectroscopy (PT-IRIS). This approach leverages one or more compact IR quantum cascade lasers, tuned to strong absorption bands in the analytes and directed to illuminate an area on a surface of interest. An IR focal plane array is used to image the surface and detect small increases in thermal emission upon laser illumination. The PT-IRIS signal is processed as a hyperspectral image cube comprised of spatial, spectral and temporal dimensions as vectors within a detection algorithm. The ability to detect trace analytes on relevant substrates is critical for stand-off applications, but is complicated by the optical and thermal analyte/substrate interactions. This manuscript describes recent PT-IRIS experimental results and analysis for traces of RDX, TNT, ammonium nitrate (AN) and sucrose on relevant substrates (steel, polyethylene, glass and painted steel panels). We demonstrate that these analytes can be detected on these substrates at relevant surface mass loadings (10 μg/cm2 to 100 μg/cm2) even at the single pixel level.

Infrared photothermal imaging spectroscopy for detection of trace explosives on surfaces.

Science.gov (United States)

Kendziora, Christopher A; Furstenberg, Robert; Papantonakis, Michael; Nguyen, Viet; Byers, Jeff; Andrew McGill, R

2015-11-01

We are developing a technique for the standoff detection of trace explosives on relevant substrate surfaces using photothermal infrared (IR) imaging spectroscopy (PT-IRIS). This approach leverages one or more compact IR quantum cascade lasers, which are tuned to strong absorption bands in the analytes and directed to illuminate an area on a surface of interest. An IR focal plane array is used to image the surface and detect increases in thermal emission upon laser illumination. The PT-IRIS signal is processed as a hyperspectral image cube comprised of spatial, spectral, and temporal dimensions as vectors within a detection algorithm. The ability to detect trace analytes at standoff on relevant substrates is critical for security applications but is complicated by the optical and thermal analyte/substrate interactions. This manuscript describes a series of PT-IRIS experimental results and analysis for traces of RDX, TNT, ammonium nitrate, and sucrose on steel, polyethylene, glass, and painted steel panels. We demonstrate detection at surface mass loadings comparable with fingerprint depositions ( 10μg/cm2 to 100μg/cm2) from an area corresponding to a single pixel within the thermal image.

Toxicities of RDX or TNT Freshly Amended or Weathered-and-Aged in Five Natural Soils to the Collembolan Folsomia candida

Science.gov (United States)

2013-05-01

Explosive 2,4,6-Trinitrotoluene. Ecotoxicol. Environ. Saf. 2002, 51, 133–144. 65 Gorontzy, T.; Drzyga, O.; Kahl, M.W.; Bruns- Nigel , D.; Breitung, J... Taylor and Francis Group: Boca Raton, FL, 2009; pp 5–33. Monteil-Rivera, F.; Paquet, L.; Deschamps, S.; Balakrishnan, V.K.; Beaulieu, C.; Hawari, J

Continuous engineering of nano-cocrystals for medical and energetic applications

Science.gov (United States)

Spitzer, D.; Risse, B.; Schnell, F.; Pichot, V.; Klaumünzer, M.; Schaefer, M. R.

2014-10-01

Cocrystals, solid mixtures of different molecules on molecular scale, are supposed to be tailor made materials with improved employability compared to their pristine individual components in domains such as medicine and explosives. In medicine, cocrystals are obtained by crystallization of active pharmaceutical ingredients with precisely chosen coformers to design medicaments that demonstrate enhanced stability, high solubility, and therefore high bioavailability and optimized drug up-take. Nanoscaling may further advance these characteristica compared to their micronsized counterparts - because of a larger surface to volume ratio of nanoparticles. In the field of energetic materials, cocrystals offer the opportunity to design smart explosives, combining high reactivity with significantly reduced sensitivity, nowadays essential for a safe manipulation and handling. Furthermore, cocrystals are used in ferroelectrics, non-linear material response and electronic organics. However, state of the art batch processes produce low volume of cocrystals of variable quality and only have produced micronsized cocrystals so far, no nano-cocrystals. Here we demonstrate the continuous preparation of pharmaceutical and energetic micro- and nano-cocrystals using the Spray Flash Evaporation process. Our laboratory scale pilot plant continuously prepared up to 8 grams per hour of Caffeine/Oxalic acid 2:1, Caffeine/Glutaric acid 1:1, TNT/CL-20 1:1 and HMX/Cl-20 1:2 nano- and submicronsized cocrystals.

Enhancement of microbial 2,4,6-trinitrotoluene transformation with increased toxicity by exogenous nutrient amendment.

Science.gov (United States)

Liang, Shih-Hsiung; Hsu, Duen-Wei; Lin, Chia-Ying; Kao, Chih-Ming; Huang, Da-Ji; Chien, Chih-Ching; Chen, Ssu-Ching; Tsai, Isheng Jason; Chen, Chien-Cheng

2017-04-01

In this study, the bacterial strain Citrobacter youngae strain E4 was isolated from 2,4,6-trinitrotoluene (TNT)-contaminated soil and used to assess the capacity of TNT transformation with/without exogenous nutrient amendments. C. youngae E4 poorly degraded TNT without an exogenous amino nitrogen source, whereas the addition of an amino nitrogen source considerably increased the efficacy of TNT transformation in a dose-dependent manner. The enhanced TNT transformation of C. youngae E4 was mediated by increased cell growth and up-regulation of TNT nitroreductases, including NemA, NfsA and NfsB. This result indicates that the increase in TNT transformation by C. youngae E4 via nitrogen nutrient stimulation is a cometabolism process. Consistently, TNT transformation was effectively enhanced when C. youngae E4 was subjected to a TNT-contaminated soil slurry in the presence of an exogenous amino nitrogen amendment. Thus, effective enhancement of TNT transformation via the coordinated inoculation of the nutrient-responsive C. youngae E4 and an exogenous nitrogen amendment might be applicable for the remediation of TNT-contaminated soil. Although the TNT transformation was significantly enhanced by C. youngae E4 in concert with biostimulation, the 96-h LC50 value of the TNT transformation product mixture on the aquatic invertebrate Tigriopus japonicas was higher than the LC50 value of TNT alone. Our results suggest that exogenous nutrient amendment can enhance microbial TNT transformation; however, additional detoxification processes may be needed due to the increased toxicity after reduced TNT transformation. Copyright © 2016 Elsevier Inc. All rights reserved.

Final report for SERDP WP-2209 Replacement melt-castable formulations for Composition B

Energy Technology Data Exchange (ETDEWEB)

Leonard, Philip [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Francois, Elizabeth Green [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-05-19

During this project we investigated a number of energetic materials both old and new and determined that most of them were unsuitable due to safety or sensitivity reasons. Unsuccessful coformulants include TNAZ and BNFF for volatility reasons, and DAAF due to thermal compatibility issues. The powerful explosive HMX became a focus of the work in later stages as it conferred excellent power while being commonly available in well-regulated particle size lots and is chemically compatible in the melt with many coformulants. Ultimately three preferred formulations emerged from this work: a formulation tested on large scale by ARDEC involving PrNQ and HMX; a formulation tested at ARDEC and LANL using a nitrate salt eutectic and HMX; a formulation tested at LANL using LLM-201 and HMX.

Investigations of Chemical and Biological Treatment Options for the Attenuation of Hexahydro-1,3,5-trinitro-1,3,5-triazine Contamination in Groundwater at Los Alamos, New Mexico

Science.gov (United States)

Heerspink, B. P.; Wang, D.; Ware, D.; Marina, O.; Perkins, G.; WoldeGabriel, G. W.; Goering, T.; Boukhalfa, H.

2017-12-01

High-explosive compounds including hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) were used extensively in weapons research and testing at Los Alamos National Laboratory (LANL) in Los Alamos, NM. Liquid effluents containing RDX released at LANL's Technical Area 16 (TA-16) resulted in the contamination of alluvial, perched-intermediate, and regional groundwater bodies. Past investigations have shown persistent RDX contamination in the perched-intermediate zone located between 225 to 311 m below ground surface, where transport studies have shown that RDX and its degradation products transport conservatively. In this study, we compared RDX degradation by chemical treatments using reduction by sodium dithionite, oxidation by potassium permanganate, and alkaline hydrolysis by carbonate/bicarbonate buffering, with microbial degradation under biostimulated conditions. The experiments were conducted using groundwater and sediments representative of the contaminated aquifer beneath TA-16. Batch testing showed that all chemical treatments degraded RDX very rapidly, with half-lives ranging from 50 minutes to 22 hours. Comparatively, RDX degradation in biostimulated reactors under strict anaerobic conditions was significantly slower, with half-lives of about 3 weeks. Results from column experiments with chemically treated sediments deviated from the results of the batch testing. Dithionite treated sediments reduced RDX with no breakthrough observed before clogging occurred at 50 pour volumes. Treatments by oxidation using potassium permanganate, and hydrolysis under buffered alkaline conditions, were less effective with complete RDX breakthrough after 2 pore volumes. No known degradation products were observed in the column effluents. RDX degradation in biostimulated columns was very effective initially for both treatments. However, the column biostimulated with safflower oil clogged very rapidly. The column biostimulated with molasses was very effective when molasses was

Toxicity of hexahydro-1,3,5-trinitro-1,3,5-triazine to larval zebrafish (Danio rerio)

Science.gov (United States)

Mukhi, S.; Pan, X.; Cobb, G.P.; Patino, R.

2005-01-01

Hexahydro-1,3,5-trinitro-1,3,5-triazine, a cyclonitramine commonly known as RDX, is used in the production of military munitions. Contamination of soil, sediment, and ground and surface waters with RDX has been reported in different places around the world. Acute and subacute toxicities of RDX have been relatively well documented in terrestrial vertebrates, but among aquatic vertebrates the information available is limited. The objective of this study was to characterize the acute toxicity of RDX to larval zebrafish. Mortality (LC50) and incidence of vertebral column deformities (EC50) were two of the end points measured in this study. The 96-h LC50 was estimated at 22.98 and 25.64 mg l-1 in two different tests. The estimated no-observed-effective- concentration (NOEC) values of RDX on lethality were 13.27 ?? 0.05 and 15.32 ?? 0.30 mg l-1; and the lowest-observed-effective- concentration (LOEC) values were 16.52 ?? 0.05 and 19.09 ?? 0.23 mg l-1 in these two tests, respectively. The 96-h EC50 for vertebral deformities on survivors from one of the acute lethality tests was estimated at 20.84 mg l-1, with NOEC and LOEC of 9.75 ?? 0.34 and 12.84 ?? 0.34 mg l-1, respectively. Behavioral aberrations were also noted in this acute toxicity study, including the occurrence of whirling movement and lethargic behavior. The acute effects of RDX on survival, incidence of deformities, and behavior of larval zebrafish occurred at the high end of the most frequently reported concentrations of RDX in aquatic environments. The chronic effects of RDX in aquatic vertebrates need to be determined for an adequate assessment of the ecological risk of environmental RDX. ?? 2005 Elsevier Ltd. All rights reserved.

Toxicity of RDX, HMX, TNB, 2,4-DNT, and 2,6-DNT to the Earthworm, Eisenia Fetida, in a Sandy Loam Soil

National Research Council Canada - National Science Library

Simini, Michael; Checkai, Ronald T; Kuperman, Roman G; Phillips, Carlton T; Kolakowski, Jan E; Kurnas, Carl W; Sunahara, Geoffrey I

2006-01-01

...), and 1,3,5-trinitrobenzene (TNB) to fill the data gaps. Tests were conducted in freshly amended and in amended soils subjected to a weathering/aging process to better reflect exposure conditions in field soils...

Toxicity of RDX, HMX, TNB, 2,4-DNT, and 2,6-DNT to the Earthworm, Eisenia Fetida, in a Sandy Loam Soil

National Research Council Canada - National Science Library

Simini, Michael; Checkai, Ronald T; Kuperman, Roman G; Phillips, Carlton T; Kolakowski, Jan E; Kurnas, Carl W; Sunahara, Geoffrey I

2006-01-01

...) for ecological risk assessment of soil contaminants at Superfund sites. Insufficient information existed to generate Eco-SSLs for explosives and related materials in soil. The earthworm (Eisenia fetida...

Effective gasoline site assessment using the D TECH trademark BTEX immunoassay

International Nuclear Information System (INIS)

Hudak, R.T.; Melby, J.M.; Stave, J.W.

1994-01-01

The application of immunoassay to environmental testing can greatly aid in assessing sites for various contaminants including PCB, TNT, RDX, PAH and BTEX. Immunoassay offers several benefits to site assessment: it is accurate, reproducible and relatively inexpensive compared to instrumental analysis. In addition, because of its ease-of-use, this technique is ideal for the field and requires minimal user training. To demonstrate not only the effectiveness of the BTEX immunoassay, but also the reliability of the field results, a gasoline contaminated site was assessed comparing the BTEX immunoassay to gas chromatography. All sampling and site related activities were executed in accordance to the USEPA SW-846 guidelines. Three (3) analyses were performed on each sample. One immunoassay analysis was performed in the field by an individual who received two (2) hours of training prior to the start of the study. A technician familiar with the immunoassay ran the second analysis in a laboratory. Finally, an independent GC laboratory certified for BTEX method 8020 and 602 performed the GC analyses. One hundred one (101) samples were analyzed: thirty-nine (39) samples were water, the other sixty-two (62) were soils ranging from clay to silt. The results and costs of the methods are compared

Advanced recognition of explosives in traces on polymer surfaces using LIBS and supervised learning classifiers.

Science.gov (United States)

Serrano, Jorge; Moros, Javier; Sánchez, Carlos; Macías, Jorge; Laserna, J Javier

2014-01-02

The large similarity existing in the spectral emissions collected from organic compounds by laser-induced breakdown spectroscopy (LIBS) is a limiting factor for the use of this technology in the real world. Specifically, among the most ambitious challenges of today's LIBS involves the recognition of an organic residue when neglected on the surface of an object of identical nature. Under these circumstances, the development of an efficient algorithm to disclose the minute differences within this highly complex spectral information is crucial for a realistic application of LIBS in countering explosive threats. An approach cemented on scatter plots of characteristic emission features has been developed to identify organic explosives when located on polymeric surfaces (teflon, nylon and polyethylene). By using selected spectral variables, the approach allows to design a concise classifier for alerting when one of four explosives (DNT, TNT, RDX and PETN) is present on the surface of the polymer. Ordinary products (butter, fuel oil, hand cream, olive oil and motor oil) cause no confusion in the decisions taken by the classifier. With rates of false negatives and false positives below 5%, results demonstrate that the classification algorithm enables to label residues according to their harmful nature in the most demanding scenario for a LIBS sensor. Copyright © 2013 Elsevier B.V. All rights reserved.

Detection of trace explosives on relevant substrates using a mobile platform for photothermal infrared imaging spectroscopy (PT-IRIS)

Science.gov (United States)

Kendziora, Christopher A.; Furstenberg, Robert; Papantonakis, Michael; Nguyen, Viet; Byers, Jeff; McGill, R. Andrew

2015-05-01

This manuscript describes the results of recent tests regarding standoff detection of trace explosives on relevant substrates using a mobile platform. We are developing a technology for detection based on photo-thermal infrared (IR) imaging spectroscopy (PT-IRIS). This approach leverages one or more microfabricated IR quantum cascade lasers, tuned to strong absorption bands in the analytes and directed to illuminate an area on a surface of interest. An IR focal plane array is used to image the surface thermal emission upon laser illumination. The PT-IRIS signal is processed as a hyperspectral image cube comprised of spatial, spectral and temporal dimensions as vectors within a detection algorithm. Increased sensitivity to explosives and selectivity between different analyte types is achieved by narrow bandpass IR filters in the collection path. We have previously demonstrated the technique at several meters of stand-off distance indoors and in field tests, while operating the lasers below the infrared eye-safe intensity limit (100 mW/cm2). Sensitivity to explosive traces as small as a single 10 μm diameter particle (~1 ng) has been demonstrated. Analytes tested here include RDX, TNT, ammonium nitrate and sucrose. The substrates tested in this current work include metal, plastics, glass and painted car panels.

IRIS Toxicological Review of Hexahydro-1,3,5-Trinitro-1,3,5 ...

Science.gov (United States)

The IRIS Toxicological Review of Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was released for external peer review in September 2016. The EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis supporting the RDX assessment and release a final report of their review. Information regarding the peer review can be found on the SAB website. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for RDX. The outcome of this project is an updated Toxicological Review and IRIS Summary for RDX that will be entered into the IRIS database.

Formulation and properties of ADN/GAP propellants

Energy Technology Data Exchange (ETDEWEB)

Menke, Klaus; Heintz, Thomas; Schweikert, Wenka; Keicher, Thomas; Krause, Horst [Fraunhofer-Institut fuer Chemische Technologie ICT, Pfinztal (Germany)

2009-06-15

In this contribution two ways are described, how it is possible to achieve perfectly cured and processible propellants with prilled ADN, low amounts of HMX 5{mu}m mps and a binder system based on GAP diole and GAP triole oligomers with and without TMETN as a nitrate ester plasticizer. It was shown how it will be possible to suppress the strongly gas forming reaction between ADN and reactive isocyanates by a mixture of stabilizers. In this way it was possible to create minimum smoke ADN/HMX/GAP/TMETN propellants cured with the triisocyanate N100. In the second part an unconventional binder system based on the 1.3 dipolar cycloaddition reaction of azido groups with acetylene compounds forming 1,2,3-triazole heterocyclic rings has been applied for ADN/GAP and AP/GAP propellants. Together with small parts of HMX formulations with ADN/HMX/GAP and the corresponding AP/HMX/GAP exhibit high thermodynamic performance, are easily processible, and cure successfully at 60 C. Their basic properties consisting of burning behavior and mechanical properties, at ambient temperature, chemical stability, and sensitivity have been investigated and are compared to each other. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

L-cysteine-capped CdTe QD-based sensor for simple and selective detection of trinitrotoluene

International Nuclear Information System (INIS)

Chen Yufang; Chen Zhang; He Yejuan; Lin Hailan; Sheng Pengtao; Liu Chengbin; Luo Shenglian; Cai Qingyun

2010-01-01

Trinitrotoluene, usually known as TNT, is a kind of chemical explosive with hazardous and toxic effects on the environment and human health. National and societal security concerns have dictated an increasing need for the analytical detection of TNT with rapidity, high sensitivity and low cost. This work demonstrates a novel method using L-cysteine-capped CdTe quantum dots (QDs) to assay TNT, based on the formation of a Meisenheimer complex between TNT and cysteine. The fluorescence (FL) of quantum dots quench because electrons of the QDs transfer to the TNT molecules via the formation of a Meisenheimer complex. TNT can be detected with a low detection limit of 1.1 nM. Studies on the selectivity of this method show that only TNT can generate an intense signal response. The synthesized QDs are excellent nanomaterials for TNT detection. In addition, TNT in soil samples is also analyzed by the proposed method.

High uptake of 2,4,6-trinitrotoluene by vetiver grass - Potential for phytoremediation?

International Nuclear Information System (INIS)

Makris, Konstantinos C.; Shakya, Kabindra M.; Datta, Rupali; Sarkar, Dibyendu; Pachanoor, Devanand

2007-01-01

2,4,6-Trinitrotoluene (TNT) is a potent mutagen, and a Group C human carcinogen that has been widely used to produce munitions and explosives. Vast areas that have been previously used as ranges, munition burning, and open detonation sites are heavily contaminated with TNT. Conventional remediation activities in such sites are expensive and damaging to the ecosystem. Phytoremediation offers a cost-effective, environment-friendly solution, utilizing plants to extract TNT from contaminated soil. We investigated the potential use of vetiver grass (Vetiveria zizanioides) to effectively remove TNT from contaminated solutions. Vetiver grass plants were grown in hydroponic systems containing 40 mg TNT L -1 for 8 d. Aqueous concentrations of TNT reached the method detection limit (∼1 μg L -1 ) within the 8-d period, demonstrating high affinity of vetiver for TNT, without any visible toxic effects. Results from this preliminary hydroponic study are encouraging, but in need of verification using TNT-contaminated soils. - Vetiver grass demonstrates ability to absorb TNT in aqueous media

Screening for biosurfactant production by 2,4,6-trinitrotoluene-transforming bacteria.

Science.gov (United States)

Avila-Arias, H; Avellaneda, H; Garzón, V; Rodríguez, G; Arbeli, Z; Garcia-Bonilla, E; Villegas-Plazas, M; Roldan, F

2017-08-01

To isolate and identify TNT-transforming cultures from explosive-contaminated soils with the ability to produce biosurfactants. Bacteria (pure and mixed cultures) were selected based on their ability to transform TNT in minimum media with TNT as the sole nitrogen source and an additional carbon source. TNT-transforming bacteria were identified by 16S rRNA gene sequencing. TNT transformation rates were significantly lower when no additional carbon or nitrogen sources were added. Surfactant production was enabled by the presence of TNT. Fourteen cultures were able to transform the explosive (>50%); of these, five showed a high transformation capacity (>90%), and six produced surfactants. All explosive-transforming cultures contained Proteobacteria of the genera Achromobacter, Stenotrophomonas, Pseudomonas, Sphingobium, Raoultella, Rhizobium and Methylopila. These cultures transformed TNT when an additional carbon source was added. Remarkably, Achromobacter spanius S17 and Pseudomonas veronii S94 have high TNT transformation rates and are surfactant producers. TNT is a highly toxic, mutagenic and carcinogenic nitroaromatic explosive; therefore, bioremediation to eliminate or mitigate its presence in the environment is essential. TNT-transforming cultures that produce surfactants are a promising method for remediation. To the best of our knowledge, this is the first report that links surfactant production and TNT transformation by bacteria. © 2017 The Society for Applied Microbiology.

Chitosan-58S bioactive glass nanocomposite coatings on TiO2 nanotube: Structural and biological properties

Science.gov (United States)

Mokhtari, H.; Ghasemi, Z.; Kharaziha, M.; Karimzadeh, F.; Alihosseini, F.

2018-05-01

Bacterial infection and insignificant osseointegration have been recognized as the main reasons of the failures of titanium based implants. The aim of this study was to apply titanium oxide nanotube (TNT) array on titanium using electrochemical anodization process as a more appropriate substrate for chitosan and chitosan-58S bioactive glass (BG) (58S-BG-Chitosan) nanocomposite coatings covered TNTs (TNT/Chiosan, TNT/58S-BG-Chitosan, respectively) through a conventional dip-coating process. Results showed that a TNT layer with average inner diameter of 82 ± 19 nm and wall's thickness of 23 ± 9 nm was developed on titanium surface using electrochemical anodization process. Roughness and contact angle measurement showed that TNT with Ra = 449 nm had highest roughness and hydrophilicity which then reduced to 86 nm and 143 nm for TNT/Chitosan and TNT/58S-BG-Chitosan, respectively. In vitro bioactivity evaluation in simulated buffer fluid (SBF) solution and antibacterial activity assay predicted that TNT/58S-BG-Chitosan was superior in bone like apatite formation and antibacterial activity against both gram-positive and gram-negative bacteria compared to Ti, TNT and TNT/Chitosan samples, respectively. Results revealed the noticeable MG63 cell attachment and proliferation on TNT/58S-BG-Chitosan coating compared to those of uncoated TNTs. These results confirmed the positive effect of using TNT substrate for natural polymer coating on improved bioactivity of implant.

(0 0 1) Facet-exposed anatase-phase TiO{sub 2} nanotube hybrid reduced graphene oxide composite: Synthesis, characterization and application in photocatalytic degradation

Energy Technology Data Exchange (ETDEWEB)

Zhou, Xun [School of Chemical Engineering of Hefei University of Technology, Hefei 230009 (China); Shi, Tiejun, E-mail: stjhfut@163.com [School of Chemical Engineering of Hefei University of Technology, Hefei 230009 (China); Wu, Jing [School of Chemical Engineering of Hefei University of Technology, Hefei 230009 (China); Zhou, Haiou [School of Chemical Engineering of Hefei University of Technology, Hefei 230009 (China); School of Materials and Chemical Engineering of Anhui University of Architecture, Hefei 230901 (China)

2013-12-15

Reduced graphene oxide (RGO) and TiO{sub 2} nanotube (TNT) with (0 0 1) facet-exposed anatase phase are covalently bonded together to synthesize TNT hybrid RGO (RGO-TNT) through consecutive process such as hydrothermal reaction, HCl washing, lyophilization and heat treatment with graphene oxide (GO), TiO{sub 2} powder and high concentration NaOH solution as the starting materials. The TNT with the diameter between 10 and 20 nm characterized by high resolution transmission electron microscopy (HRTEM) is in anatase phase proven by X-ray diffraction (XRD) and HRTEM. Additionally, the more active (0 0 1) facet is exposed identified by HRTEM. More significantly, TNT is bridged to RGO by C-Ti bond by the measurement of X-ray photoelectron spectroscopy (XPS). The photoluminescence (PL) spectra has testified that RGO in RGO-TNT can transfer and accept photoelectrons from TNT. The photocatalytic activity of RGO-TNT for degrading methylene blue (MB) is enhanced by contrast with pure TNT, and changeable by adjusting the mass ratios of GO to TiO{sub 2} powder. Simultaneously, lyophilization is benefit for maintaining the high active surface area of RGO-TNT, which is deeply in relationship with a higher photocatalytic activity. After four running cycles of photocatalytic degradation, RGO-TNT has shown a high stability and perfect reproducibility.

Titania nanotube delivery fetal bovine serum for enhancing MC3T3-E1 activity and osteogenic gene expression

International Nuclear Information System (INIS)

Peng, Jing; Zhang, Xinming; Li, Zhaoyang; Liu, Yunde; Yang, Xianjin

2015-01-01

Titania nanotube (TNT) delivery of fetal bovine serum (FBS) was conducted on titanium (Ti) to enhance bone tissue repair. Scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) showed FBS increased the tube wall thickness and decreased the tube diameter. Attenuated total reflectance Fourier transform infrared further confirmed that FBS completely covered the TNT and changed the surface composition. Water contact angle tests showed TNT/FBS possessed hydrophilic properties. Compared to original Ti, the TNT/FBS group had more attached osteoblasts after 2 h and enhanced filopodia growth at 0.5 h. Significantly, more osteoblasts were also observed on TNT/FBS after 7 d culturing. FBS was released steadily from TNT; about 70% of FBS had been released at 3 d and 90% at 5 d, as shown by the bicinchoninic acid method. TNT/FBS also enhanced subsequent osteoblast differentiation and gene expression; the quantum real-time polymerase chain reaction test showed that TNT/FBS up-regulated alkaline phosphatase and osteocalcin gene expression at 7 d and 14 d. Therefore, TNT/FBS delivered sustained in situ nutrition and enhanced osteoblast activity and osteogenic gene expression. - Highlights: • Fetal Bovine Serum (FBS) was filled in titania nanotube (TNT) structures. • FBS provided sustained-release in situ nutrition for surface osteoblast growth. • TNT/FBS enhanced osteoblast activity and osteogenic gene expression

Titania nanotube delivery fetal bovine serum for enhancing MC3T3-E1 activity and osteogenic gene expression

Energy Technology Data Exchange (ETDEWEB)

Peng, Jing, E-mail: pengjingtd@163.com [Airport College, Civil Aviation University of China, Tianjin 300300 (China); Zhang, Xinming, E-mail: xinmingmail@163.com [Tianjin Product Quality Inspection Technology Research Institute, Tianjin 300384 (China); School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China); Li, Zhaoyang [School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China); Liu, Yunde [School of Medical Laboratory, Tianjin Medical University, Tianjin 300203 (China); Yang, Xianjin [School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China)

2015-11-01

Titania nanotube (TNT) delivery of fetal bovine serum (FBS) was conducted on titanium (Ti) to enhance bone tissue repair. Scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) showed FBS increased the tube wall thickness and decreased the tube diameter. Attenuated total reflectance Fourier transform infrared further confirmed that FBS completely covered the TNT and changed the surface composition. Water contact angle tests showed TNT/FBS possessed hydrophilic properties. Compared to original Ti, the TNT/FBS group had more attached osteoblasts after 2 h and enhanced filopodia growth at 0.5 h. Significantly, more osteoblasts were also observed on TNT/FBS after 7 d culturing. FBS was released steadily from TNT; about 70% of FBS had been released at 3 d and 90% at 5 d, as shown by the bicinchoninic acid method. TNT/FBS also enhanced subsequent osteoblast differentiation and gene expression; the quantum real-time polymerase chain reaction test showed that TNT/FBS up-regulated alkaline phosphatase and osteocalcin gene expression at 7 d and 14 d. Therefore, TNT/FBS delivered sustained in situ nutrition and enhanced osteoblast activity and osteogenic gene expression. - Highlights: • Fetal Bovine Serum (FBS) was filled in titania nanotube (TNT) structures. • FBS provided sustained-release in situ nutrition for surface osteoblast growth. • TNT/FBS enhanced osteoblast activity and osteogenic gene expression.

Chemically catalyzed uptake of 2,4,6-trinitrotoluene by Vetiveria zizanioides

International Nuclear Information System (INIS)

Makris, Konstantinos C.; Shakya, Kabindra M.; Datta, Rupali; Sarkar, Dibyendu; Pachanoor, Devanand

2007-01-01

The efficiency of vetiver grass (Vetiveria zizanioides) in removing 2,4,6-trinitrotoluene (TNT) from aqueous media was explored in the presence of a common agrochemical, urea, used as a chaotropic agent. Chaotropic agents disrupt water structure, increasing solubilization of hydrophobic compounds (TNT), thus, enhancing plant TNT uptake. The primary objectives of this study were to: (i) characterize TNT absorption by vetiver in hydroponic media, and (ii) determine the effect of urea on chemically catalyzing TNT uptake by vetiver grass in hydroponic media. Results showed that vetiver exhibited a high TNT uptake capacity (1.026 mg g -1 ), but kinetics were slow. Uptake was considerably enhanced in the presence of urea, which significantly (p<0.001) increased the 2nd-order reaction rate constant over that of the untreated (no urea) control. Three major TNT metabolites were detected in the roots, but not in the shoot, namely 1,3,5-trinitrobenzene, 4-amino 2,6-dinitrotoluene, and 2-amino 4,6-dinitrotoluene, indicating TNT degradation by vetiver grass. - A common agrochemical, urea catalyzes TNT removal by vetiver grass in aqueous media

Chemically catalyzed uptake of 2,4,6-trinitrotoluene by Vetiveria zizanioides

Energy Technology Data Exchange (ETDEWEB)

Makris, Konstantinos C. [Environmental Geochemistry Laboratory, Department of Earth and Environmental Science, College of Sciences, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249 (United States); Shakya, Kabindra M. [Environmental Geochemistry Laboratory, Department of Earth and Environmental Science, College of Sciences, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249 (United States); Datta, Rupali [Environmental Geochemistry Laboratory, Department of Earth and Environmental Science, College of Sciences, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249 (United States); Sarkar, Dibyendu [Environmental Geochemistry Laboratory, Department of Earth and Environmental Science, College of Sciences, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249 (United States)]. E-mail: dibyendu.sarkar@utsa.edu; Pachanoor, Devanand [Environmental Geochemistry Laboratory, Department of Earth and Environmental Science, College of Sciences, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249 (United States)

2007-07-15

The efficiency of vetiver grass (Vetiveria zizanioides) in removing 2,4,6-trinitrotoluene (TNT) from aqueous media was explored in the presence of a common agrochemical, urea, used as a chaotropic agent. Chaotropic agents disrupt water structure, increasing solubilization of hydrophobic compounds (TNT), thus, enhancing plant TNT uptake. The primary objectives of this study were to: (i) characterize TNT absorption by vetiver in hydroponic media, and (ii) determine the effect of urea on chemically catalyzing TNT uptake by vetiver grass in hydroponic media. Results showed that vetiver exhibited a high TNT uptake capacity (1.026 mg g{sup -1}), but kinetics were slow. Uptake was considerably enhanced in the presence of urea, which significantly (p<0.001) increased the 2nd-order reaction rate constant over that of the untreated (no urea) control. Three major TNT metabolites were detected in the roots, but not in the shoot, namely 1,3,5-trinitrobenzene, 4-amino 2,6-dinitrotoluene, and 2-amino 4,6-dinitrotoluene, indicating TNT degradation by vetiver grass. - A common agrochemical, urea catalyzes TNT removal by vetiver grass in aqueous media.

High Pressure-Temperature Phase Diagram of 1,1-diamino-2,2-dinitroethylene

Science.gov (United States)

Bishop, Matthew; Chellappa, Raja; Liu, Zhenxian; Preston, Daniel; Sandstrom, Mary; Dattelbaum, Dana; Vohra, Yogesh; Velisavljevic, Nenad

2013-06-01

1,1-diamino-2,2-dinitroethelyne (FOX-7) is a less sensitive energetic material with performance comparable to commonly used secondary explosives such as RDX and HMX. At ambient pressure, FOX-7 exhibits complex polymorphism with at least three structurally distinct phases (α, β, and γ) . In this study, we have investigated the high P-T stability of FOX-7 polymorphs using synchrotron mid-infrared (MIR) spectroscopy. At ambient pressure, our MIR spectra confirmed the known α --> β (110 °C) and β --> γ (160 °C) phase transitions; as well as, indicated an additional phase transition, γ --> δ (210°C), with the δ phase being stable up to 250 °C prior to melt/decomposition. In situ MIR spectra obtained during isobaric heating at 0.9 GPa revealed that the α --> β transition occurs at 180 °C, while β --> β + δ phase transition shifted to 300 °C with suppression of γ phase. Decomposition was observed above 325 °C. Based on multiple high P-T measurements, we have established the first high P-T phase diagram of FOX-7. This work was, in part, supported by the US DOE under contract No. DE-AC52-06NA25396 and Science Campaign 2 Program. MB acknowledges additional support from the NSF BD program. Use of NSLS (DE-AC02-98CH10886) beamline U2A (COMPRES, No.EAR01-35554, CDAC).

Thermal reactivity of some nitro- and nitroso-compounds derived from 1,3,5,7-tetraazabicyclo[3.3.1]nonane at contamination by ammonium nitrate.

Science.gov (United States)

Zeman, Svatopluk; Shu, Yuanjie; Friedl, Zdenek; Vágenknecht, Jirí

2005-05-20

Thermal reactivity of 3,7-dinitro-1,3,5,7-tetraazabicyclo[3.3.1]nonane (DPT), 3,7-dinitroso-1,3,5,7-tetraazabicyclo[3.3.1]nonane (DNPT), 1,3,5-trinitroso-1,3,5-triazinane (TMTA or R-salt), 1,3,5-trinitro-1,3,5-triazinane (hexogen or RDX), 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetrazocane (DADN), alpha-modification of the 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (octogen or HMX) and of their mixtures with 2wt.% of ammonium nitrate (AN) has been examined by means of non-isothermal differential thermal analysis. The resulting data were analyzed according to the Kissinger method. The reactivity was expressed as the E(a)R(-1) slopes of the Kissinger relationship. A relatively high reactivity has been found with mixtures of DPT and DNPT with AN. Electronic charges q(N) at nitrogen atoms in molecules of the compounds studied were calculated by means of ab initio DFT B3LYP/6-31G** method. The relationships were confirmed between the slopes E(a)R(-1) and the q(N) values for the nitrogen atoms primarily undergoing reaction. On the basis of these relationships it is stated that the destabilizing effect of AN is due to acidolytic attack of nitric acid (resulting from dissociation of ammonium nitrate) at the nitrogen atoms with the most negative q(N) values in the molecules of the compounds studied.

Cardiac Troponin Elevation Predicts Mortality in Patients Undergoing Orthotopic Liver Transplantation

Directory of Open Access Journals (Sweden)

David Snipelisky

2013-01-01

Full Text Available Introduction. While patients undergoing orthotopic liver transplantation (OLT have high cardiovascular event rates, preoperative risk stratification may not necessarily predict those susceptible patients. Troponin T (TnT may help predict patients at risk for cardiovascular complications. Methods. Consecutive patients undergoing OLT at Mayo Clinic in Florida between 1998 and 2010 who had TnT obtained within 10 days following surgery were included. Three groups were compared based on TnT level: (1 normal (TnT ≤0.01 ng/mL, (2 intermediate (TnT 0.02–0.11 ng/mL, and (3 elevated (TnT >0.11 ng/mL. Overall and cardiovascular mortality was assessed. Results. Of the 78 patients included, there was no difference in age, gender, severity of liver disease, and echocardiographic findings. Patients in the normal and intermediate TnT groups had a lower overall mortality rate (14.3% and 0%, resp. when compared with those with elevated TnT (50%; P=0.001. Patients in the elevated TnT group had a cardiovascular mortality rate of 37.5% compared with 1.4% in the other groups combined (P<0.01. The elevated TnT group had a much higher mortality rate when compared with those in the intermediate group (P<0.0001. Conclusion. TnT may accurately help risk stratify patients in the early postoperative setting to better predict cardiovascular complications.

Photolysis of 2,4,6-trinitrotoluene in seawater and estuary water: Impact of pH, temperature, salinity, and dissolved organic matter

International Nuclear Information System (INIS)

Luning Prak, Dianne J.; Breuer, James E.T.; Rios, Evelyn A.; Jedlicka, Erin E.; O'Sullivan, Daniel W.

2017-01-01

The influence of salinity, pH, temperature, and dissolved organic matter on the photolysis rate of 2,4,6-trinitrotoluene (TNT) in marine, estuary, and laboratory-prepared waters was studied using a Suntest CPS +® solar simulator equipped with optical filters. TNT degradation rates were determined using HPLC analysis, and products were identified using LC/MS. Minimal or no TNT photolysis occurred under a 395-nm long pass filter, but under a 295-nm filter, first-order TNT degradation rate constants and apparent quantum yields increased with increasing salinity in both natural and artificial seawater. TNT rate constants increased slightly with increasing temperature (10 to 32 °C) but did not change significantly with pH (6.4 to 8.1). The addition of dissolved organic matter (up to 5 mg/L) to ultrapure water, artificial seawater, and natural seawater increased the TNT photolysis rate constant. Products formed by TNT photolysis in natural seawater were determined to be 2,4,6-trinitrobenzaldehyde, 1,3,5-trinitrobenzene, 2,4,6-trinitrobenzoic acid, and 2-amino-4,6-dinitrobenzoic acid. - Highlights: • 2,4,6-trinitrotoluene (TNT) was photolyzed in marine, estuary, & laboratory waters. • TNT photolysis rates increased with increasing salinity & dissolved organic matter. • Temperature and pH had minimal impact on TNT photolysis in marine waters. • In seawater, TNT photolysis produced 1,3,5-trinitrobenzene & trinitrobenzaldehyde. • Polar products were 2,4,6-trinobenzoic acid & 2-amino-4,6-dinitrobenzoic acid.

Coral-zooxanthellae meta-transcriptomics reveals integrated response to pollutant stress.

Science.gov (United States)

Gust, Kurt A; Najar, Fares Z; Habib, Tanwir; Lotufo, Guilherme R; Piggot, Alan M; Fouke, Bruce W; Laird, Jennifer G; Wilbanks, Mitchell S; Rawat, Arun; Indest, Karl J; Roe, Bruce A; Perkins, Edward J

2014-07-12

Corals represent symbiotic meta-organisms that require harmonization among the coral animal, photosynthetic zooxanthellae and associated microbes to survive environmental stresses. We investigated integrated-responses among coral and zooxanthellae in the scleractinian coral Acropora formosa in response to an emerging marine pollutant, the munitions constituent, 1,3,5-trinitro-1,3,5 triazine (RDX; 5 day exposures to 0 (control), 0.5, 0.9, 1.8, 3.7, and 7.2 mg/L, measured in seawater). RDX accumulated readily in coral soft tissues with bioconcentration factors ranging from 1.1 to 1.5. Next-generation sequencing of a normalized meta-transcriptomic library developed for the eukaryotic components of the A. formosa coral holobiont was leveraged to conduct microarray-based global transcript expression analysis of integrated coral/zooxanthellae responses to the RDX exposure. Total differentially expressed transcripts (DET) increased with increasing RDX exposure concentrations as did the proportion of zooxanthellae DET relative to the coral animal. Transcriptional responses in the coral demonstrated higher sensitivity to RDX compared to zooxanthellae where increased expression of gene transcripts coding xenobiotic detoxification mechanisms (i.e. cytochrome P450 and UDP glucuronosyltransferase 2 family) were initiated at the lowest exposure concentration. Increased expression of these detoxification mechanisms was sustained at higher RDX concentrations as well as production of a physical barrier to exposure through a 40% increase in mucocyte density at the maximum RDX exposure. At and above the 1.8 mg/L exposure concentration, DET coding for genes involved in central energy metabolism, including photosynthesis, glycolysis and electron-transport functions, were decreased in zooxanthellae although preliminary data indicated that zooxanthellae densities were not affected. In contrast, significantly increased transcript expression for genes involved in cellular energy production

Effect of Energetic Materials on Thermal Decomposition of Phase-Stabilised Ammonium Nitrate - An Eco-Friendly Oxidiser

OpenAIRE

Suresh Mathew; K. Krishnan; K. N. Ninan

1999-01-01

Phase-stabilised ammonium nitrate (PSAN) was prepared by incorporating copper (II) diamine nitrate in the ammonium nitrate (AN) crystal lattice, thereby avoiding the abrupt volume change within the useful temperature range. The effect of RDX on the thermal decomposition of PSAN has been investigated. Decomposition temperatures of PSAN and RDX are almost in the same temperature range. The synergetic effect of the interaction between PSAN and RDX resulted in a net exothermic reaction of PSAN. T...

Complete dissipation of 2,4,6-trinitrotoluene by in-vessel composting

NARCIS (Netherlands)

Gümüscü, B.; Cekmecelioglu, Deniz; Tekinay, Turgay

2015-01-01

We demonstrate complete removal of 2,4,6-trinitrotoluene (TNT) in 15 days using an in-vessel composting system, which is amended with TNT-degrading bacteria strains. A mixture of TNT, food waste, manure, wood chips, soil and TNT-degrading bacteria consortium are co-composted for 15 days in an

Preparation of explosive nanoparticles in a porous chromium(III) oxide matrix: a first attempt to control the reactivity of explosives

International Nuclear Information System (INIS)

Comet, M; Siegert, B; Pichot, V; Gibot, P; Spitzer, D

2008-01-01

This paper reports the first attempt to control the combustion and the detonation properties of a high explosive through its structure. A porous chromium(III) oxide matrix produced by the combustion of ammonium dichromate was infiltrated by hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). The structure of the Cr 2 O 3 matrix was studied by both scanning and transmission electron microscopy (SEM, TEM); the Cr 2 O 3 /RDX nanocomposites were characterized by nitrogen adsorption. A mathematical model based on these techniques was used to demonstrate that the Cr 2 O 3 matrix encloses and stabilizes RDX particles at the nanoscale. The decomposition process of the nanocomposites was investigated by atomic force microscopy (AFM). The reactivity and sensitivity of the nanocomposites were studied by impact and friction tests, differential scanning calorimetry (DSC), time-resolved cinematography and detonation experiments, and were correlated with their structure. The size of RDX nanoparticles and their distribution in the Cr 2 O 3 matrix have an important influence on their reactivity. The reactive properties of nanostructured RDX differ significantly from those of classical micron-sized RDX. For instance, the melting point disappears and the decomposition temperature is significantly lowered. The quantization of the explosive particles in the Cr 2 O 3 matrix decreases the sensitivity to mechanical stress and allows controlling the decomposition mode-i.e. combustion versus detonation

Nanotubular topography enhances the bioactivity of titanium implants.

Science.gov (United States)

Huang, Jingyan; Zhang, Xinchun; Yan, Wangxiang; Chen, Zhipei; Shuai, Xintao; Wang, Anxun; Wang, Yan

2017-08-01

Surface modification on titanium implants plays an important role in promoting mesenchymal stem cell (MSC) response to enhance osseointegration persistently. In this study, nano-scale TiO 2 nanotube topography (TNT), micro-scale sand blasted-acid etched topography (SLA), and hybrid sand blasted-acid etched/nanotube topography (SLA/TNT) were fabricated on the surfaces of titanium implants. Although the initial cell adherence at 60 min among TNT, SLA and TNT/SLA was not different, SLA and SLA/TNT presented to be rougher and suppressed the proliferation of MSC. TNT showed hydrophilic surface and balanced promotion of cellular functions. After being implanted in rabbit femur models, TNT displayed the best osteogenesis inducing ability as well as strong bonding strength to the substrate. These results indicate that nano-scale TNT provides favorable surface topography for improving the clinical performance of endosseous implants compared with micro and hybrid micro/nano surfaces, suggesting a promising and reliable surface modification strategy of titanium implants for clinical application. Copyright © 2017 Elsevier Inc. All rights reserved.

Asymmetric photoelectric property of transparent TiO2 nanotube films loaded with Au nanoparticles

International Nuclear Information System (INIS)

Wang, Hui; Liang, Wei; Liu, Yiming; Zhang, Wanggang; Zhou, Diaoyu; Wen, Jing

2016-01-01

Highlights: • Highly transparent films of TiO 2 nanotube arrays were directly fabricated on FTO glasses. • Semitransparent TNT-Au composite films were obtained and exhibited excellent photoelectrocatalytic ability. • Back-side of TNT-Au composite films was firstly irradiated and tested to compare with front-side of films. - Abstract: Semitransparent composite films of Au loaded TiO 2 nanotubes (TNT-Au) were prepared by sputtering Au nanoparticles on highly transparent TiO 2 nanotubes films, which were fabricated directly on FTO glasses by anodizing the Ti film sputtered on the FTO glasses. Compared with pure TNT films, the prepared TNT-Au films possessed excellent absorption ability and high photocurrent response and improved photocatalytic activity under visible-light irradiation. It could be concluded that Au nanoparticles played important roles in improving the photoelectrochemical performance of TNT-Au films. Moreover, in this work, both sides of TNT-Au films were researched and compared owing to theirs semitransparency. It was firstly found that the photoelectric activity of TNT-Au composite films with back-side illumination was obviously superior to front-side illumination.

Tunneling Nanotubes: Intimate Communication between Myeloid Cells.

Science.gov (United States)

Dupont, Maeva; Souriant, Shanti; Lugo-Villarino, Geanncarlo; Maridonneau-Parini, Isabelle; Vérollet, Christel

2018-01-01

Tunneling nanotubes (TNT) are dynamic connections between cells, which represent a novel route for cell-to-cell communication. A growing body of evidence points TNT towards a role for intercellular exchanges of signals, molecules, organelles, and pathogens, involving them in a diverse array of functions. TNT form among several cell types, including neuronal cells, epithelial cells, and almost all immune cells. In myeloid cells (e.g., macrophages, dendritic cells, and osteoclasts), intercellular communication via TNT contributes to their differentiation and immune functions. Importantly, TNT enable myeloid cells to communicate with a targeted neighboring or distant cell, as well as with other cell types, therefore creating a complex variety of cellular exchanges. TNT also contribute to pathogen spread as they serve as "corridors" from a cell to another. Herein, we addressed the complexity of the definition and in vitro characterization of TNT in innate immune cells, the different processes involved in their formation, and their relevance in vivo . We also assess our current understanding of how TNT participate in immune surveillance and the spread of pathogens, with a particular interest for HIV-1. Overall, despite recent progress in this growing research field, we highlight that further investigation is needed to better unveil the role of TNT in both physiological and pathological conditions.

Tunneling Nanotubes: Intimate Communication between Myeloid Cells

Directory of Open Access Journals (Sweden)

Maeva Dupont

2018-01-01

Full Text Available Tunneling nanotubes (TNT are dynamic connections between cells, which represent a novel route for cell-to-cell communication. A growing body of evidence points TNT towards a role for intercellular exchanges of signals, molecules, organelles, and pathogens, involving them in a diverse array of functions. TNT form among several cell types, including neuronal cells, epithelial cells, and almost all immune cells. In myeloid cells (e.g., macrophages, dendritic cells, and osteoclasts, intercellular communication via TNT contributes to their differentiation and immune functions. Importantly, TNT enable myeloid cells to communicate with a targeted neighboring or distant cell, as well as with other cell types, therefore creating a complex variety of cellular exchanges. TNT also contribute to pathogen spread as they serve as “corridors” from a cell to another. Herein, we addressed the complexity of the definition and in vitro characterization of TNT in innate immune cells, the different processes involved in their formation, and their relevance in vivo. We also assess our current understanding of how TNT participate in immune surveillance and the spread of pathogens, with a particular interest for HIV-1. Overall, despite recent progress in this growing research field, we highlight that further investigation is needed to better unveil the role of TNT in both physiological and pathological conditions.

Novel approach to the preparation of organic energetic film for microelectromechanical systems and microactuator applications.

Science.gov (United States)

Wang, Jun; Zhang, Wenchao; Wang, Lianwei; Shen, Ruiqi; Xu, Xing; Ye, Jiahai; Chao, Yimin

2014-07-23

An activated RDX-Fe2O3 xerogel in a Si-microchannel plate (MCP) has been successfully prepared by a novel propylene epoxide-mediated sol-gel method. A decrease of nearly 40 °C in decomposition temperature has been observed compared with the original cyclotrimethylene trinitramine (RDX). The RDX-Fe2O3 xerogel can release gas and solid matter simultaneously, and the ratio of gas to solid can be tailored easily by changing the initial proportions of RDX and FeCl3·6H2O, which significantly enhances the explosive and propulsion effects and is of great benefit to the applications. The approach, which is simple, safe, and fully compatible with MEMS technology, opens a new route to the introduction of organic energetic materials to a silicon substrate.

Systems Biology Approach to Bioremediation of Nitroaromatics: Constraint-Based Analysis of 2,4,6-Trinitrotoluene Biotransformation by Escherichia coli

Directory of Open Access Journals (Sweden)

Maryam Iman

2017-08-01

Full Text Available Microbial remediation of nitroaromatic compounds (NACs is a promising environmentally friendly and cost-effective approach to the removal of these life-threating agents. Escherichia coli (E. coli has shown remarkable capability for the biotransformation of 2,4,6-trinitro-toluene (TNT. Efforts to develop E. coli as an efficient TNT degrading biocatalyst will benefit from holistic flux-level description of interactions between multiple TNT transforming pathways operating in the strain. To gain such an insight, we extended the genome-scale constraint-based model of E. coli to account for a curated version of major TNT transformation pathways known or evidently hypothesized to be active in E. coli in present of TNT. Using constraint-based analysis (CBA methods, we then performed several series of in silico experiments to elucidate the contribution of these pathways individually or in combination to the E. coli TNT transformation capacity. Results of our analyses were validated by replicating several experimentally observed TNT degradation phenotypes in E. coli cultures. We further used the extended model to explore the influence of process parameters, including aeration regime, TNT concentration, cell density, and carbon source on TNT degradation efficiency. We also conducted an in silico metabolic engineering study to design a series of E. coli mutants capable of degrading TNT at higher yield compared with the wild-type strain. Our study, therefore, extends the application of CBA to bioremediation of nitroaromatics and demonstrates the usefulness of this approach to inform bioremediation research.

Accumulation of {sup 14}C-trinitrotoluene and related nonextractable (bound) residues in Eisenia fetida

Energy Technology Data Exchange (ETDEWEB)

Belden, Jason B., E-mail: jbelden@okstate.edu [Department of Zoology, Oklahoma State University, Stillwater, OK 74078 (United States); Lotufo, Guillerme R. [US Army Engineer Research and Development Center, Vicksburg, MS 39180 (United States); Chambliss, C. Kevin [Department of Chemistry, Baylor University, Waco, TX 76798 (United States); Fisher, Jonathan C. [Department of Zoology, Oklahoma State University, Stillwater, OK 74078 (United States); Johnson, Dave R.; Boyd, Robert E.; Sims, Jerre G. [US Army Engineer Research and Development Center, Vicksburg, MS 39180 (United States)

2011-05-15

To determine if trinitrotoluene (TNT) forms nonextractable residues in earthworms and to measure the relative degree of accumulation as compared to TNT and its deaminated metabolites, Eisenia fetida was exposed to {sup 14}C-TNT using dermal contact to filter paper or exposure to soil. Nonextractable residues made up 32-68% of total body burden depending on exposure media and depuration time. Parent TNT accounted for less than 3% of radioactivity, while ADNTs accounted for 7-38%. Elimination half-lives were 61-120 h for TNT, ADNTs, and DANTs, which was significantly lower than the half-lives found for nonextractable residues, 201-240 h. However, over 80% of the nonextractable residue was solubilized using weak acid (pH 2). Based on our findings that TNT accumulation occurs primarily as nonextractable residues, which have a longer half-life, and that nonextractable residues can be solubilized, we propose that nonextractable residues could be used as a selective biomarker for assessing TNT contamination. - Highlights: > Trinitrotoluene accumulation in earthworms primarily occurs as nonextractable residues. > Nonextractable residues have a significantly longer half life in the worm as compared to TNT and its solvent-extractable deaminated metabolites. > Nonextractable residue may be useful as a biomarker for exposure to TNT. - The majority of trinitrotoluene accumulation in earthworms occurs as nonextractable residues that have a significantly longer half life in the worm as compared to TNT and its solvent-extractable deaminated metabolites.

Identification of explosives and drugs and inspection of material defects with THz radiation

Science.gov (United States)

Zhang, Cunlin; Mu, Kaijun; Jiang, Xue; Jiao, Yueying; Zhang, Liangliang; Zhou, Qingli; Zhang, Yan; Shen, Jingling; Zhao, Guoshong; Zhang, X.-C.

2008-03-01

We report the sensing of explosive materials and illicit drugs by using terahertz time-domain spectroscopy (THz-TDS) and imaging. Several explosive materials, such as γ-HNIW, RDX, 2,4-DNT, TNT, Nitro-aniline, and illicit drugs, such as methamphetamine (MA) etc were researched here. Non-destructive testing, as one of the major applications of THz imaging, can be applied to an area of critical need: the testing of aerospace materials. Composite materials such as carbon fiber are widely used in this industry. The nature of their use requires technologies that are able to differentiate between safe and unsafe materials, due to either manufacturing tolerance or damage acquired while in use. In this paper, we discuss the applicability of terahertz (THz) imaging systems to this purpose, focusing on graphite fiber composite materials, carbon silicon composite materials and so on. We applied THz imaging technology to evaluate the fire damage to a variety of carbon fiber composite samples. Major carbon fiber materials have polarization-dependent reflectivity in THz frequency range, and we show how the polarization dependence changes versus the burned damage level. Additionally, time domain information acquired through a THz time-domain spectroscopy (TDS) system provides further information with which to characterize the damage. We also detect fuel tank insulation foam panel defects with pulse and continuous-wave (CW) terahertz system.

Effects of Titanium Oxide Nanotube Arrays with Different Lengths on the Characteristics of Dye-Sensitized Solar Cells

Directory of Open Access Journals (Sweden)

Chin-Guo Kuo

2013-01-01

Full Text Available The self-aligned highly ordered TiO2 nanotube (TNT arrays were fabricated by potentiostatic anodization of Ti foil, and we found that the TNT-array length and diameter were dependent on the electrolyte (NH4F concentration in ethylene glycol and anodization time. The characteristics of the fabricated TNT arrays were characterized by XRD pattern, FESEM, and absorption spectrum. As the electrolyte NH4F concentration in the presence of H2O (2 vol% with anodization was changed from 0.25 to 0.75 wt% and the anodization period was increased from 1 to 5 h, the TNT-array length was changed from 9.55 to 30.2 μm and the TNT-array diameter also increased. As NH4F concentration was 0.5 wt%, the prepared TNT arrays were also used to fabricate the dye-sensitized solar cells (DSSCs. We would show that the measured photovoltaic performance of the DSSCs was dependent on the TNT-array length.

Phototransformation of 2,4,6-trinitrotoluene: Sensitized by riboflavin under different irradiation spectral range

International Nuclear Information System (INIS)

Yang Xin; Zhao Xueheng; Hwang, H.-M.

2007-01-01

Riboflavin-sensitized phototransformation of 2,4,6-trinitrotoluene (TNT) under natural sunlight was investigated with reverse-phase high performance liquid chromatography/mass spectrometry (HPLC/MS) and gas chromatography/mass spectrometry (GC/MS). The effect of different spectral region of sunlight on TNT phototransformation in the absence or presence of riboflavin was also investigated by using optical filters with cut-off at 400 or 455 nm. The concentration of riboflavin in the phototransformation of TNT was optimized. Concentration of riboflavin and TNT was 1.0 and 50 μM, respectively. The rates of phototransformation of TNT under natural sunlight in the presence or absence of riboflavin were conformed to initial pseudo-first-order rate equation. The photolysis half life of TNT in the presence of riboflavin was 21.87 min, compared to 39 min in the absence of riboflavin under natural sunlight. Two major phototransformation products of TNT, 3,5-dinitroaniline (3,5-DNA) and 1,3,5-trinitrobenzene (1,3,5-TNB), were detected in the samples in the presence of riboflavin receiving irradiation at full wavelength or wavelength >400 nm. The results indicate that riboflavin mediates TNT sensitized-phototransfomation under natural sunlight or near-UV-vis light

Biocompatibility of Titania Nanotube Coatings Enriched with Silver Nanograins by Chemical Vapor Deposition

Directory of Open Access Journals (Sweden)

Piotr Piszczek

2017-09-01

Full Text Available Bioactivity investigations of titania nanotube (TNT coatings enriched with silver nanograins (TNT/Ag have been carried out. TNT/Ag nanocomposite materials were produced by combining the electrochemical anodization and chemical vapor deposition methods. Fabricated coatings were characterized by scanning electron microscopy (SEM, X-ray photoelectron spectroscopy (XPS, and Raman spectroscopy. The release effect of silver ions from TNT/Ag composites immersed in bodily fluids, has been studied using inductively coupled plasma mass spectrometry (ICP-MS. The metabolic activity assay (MTT was applied to determine the L929 murine fibroblasts adhesion and proliferation on the surface of TNT/Ag coatings. Moreover, the results of immunoassays (using peripheral blood mononuclear cells—PBMCs isolated from rats allowed the estimation of the immunological activity of TNT/Ag surface materials. Antibacterial activity of TNT/Ag coatings with different morphological and structural features was estimated against two Staphylococcus aureus strains (ATCC 29213 and H9. The TNT/Ag nanocomposite layers produced revealed a good biocompatibility promoting the fibroblast adhesion and proliferation. A desirable anti-biofilm activity against the S. aureus reference strain was mainly noticed for these TiO2 nanotube coatings, which contain dispersed Ag nanograins deposited on their surface.

Three Nightmare Traits in Leaders

Directory of Open Access Journals (Sweden)

Reinout E. de Vries

2018-06-01

Full Text Available This review offers an integration of dark leadership styles with dark personality traits. The core of dark leadership consists of Three Nightmare Traits (TNT—leader dishonesty, leader disagreeableness, and leader carelessness—that are conceptualized as contextualized personality traits aligned with respectively (low honesty-humility, (low agreeableness, and (low conscientiousness. It is argued that the TNT, when combined with high extraversion and low emotionality, can have serious (“explosive” negative consequences for employees and their organizations. A Situation-Trait-Outcome Activation (STOA model is presented in which a description is offered of situations that are attractive to TNT leaders (situation activation, situations that activate TNT traits (trait activation, and the kinds of outcomes that may result from TNT behaviors (outcome activation. Subsequently, the TNT and STOA models are combined to offer a description of the organizational actions that may strengthen or weaken the TNT during six career stages: attraction, selection, socialization, production, promotion, and attrition. Except for mainly negative consequences of the TNT, possible positive consequences of TNT leadership are also explored, and an outline of a research program is offered that may provide answers to the most pressing questions in dark leadership research.

Asymmetric photoelectric property of transparent TiO{sub 2} nanotube films loaded with Au nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Wang, Hui [College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024 (China); College of Applied Science, Taiyuan University of Science and Technology, Taiyuan, Shanxi 030024 (China); Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Ministry of Education, Taiyuan, Shanxi 030024 (China); Liang, Wei, E-mail: 986903124@qq.com [College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024 (China); Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Ministry of Education, Taiyuan, Shanxi 030024 (China); Liu, Yiming; Zhang, Wanggang; Zhou, Diaoyu; Wen, Jing [College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024 (China); Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Ministry of Education, Taiyuan, Shanxi 030024 (China)

2016-11-15

Highlights: • Highly transparent films of TiO{sub 2} nanotube arrays were directly fabricated on FTO glasses. • Semitransparent TNT-Au composite films were obtained and exhibited excellent photoelectrocatalytic ability. • Back-side of TNT-Au composite films was firstly irradiated and tested to compare with front-side of films. - Abstract: Semitransparent composite films of Au loaded TiO{sub 2} nanotubes (TNT-Au) were prepared by sputtering Au nanoparticles on highly transparent TiO{sub 2} nanotubes films, which were fabricated directly on FTO glasses by anodizing the Ti film sputtered on the FTO glasses. Compared with pure TNT films, the prepared TNT-Au films possessed excellent absorption ability and high photocurrent response and improved photocatalytic activity under visible-light irradiation. It could be concluded that Au nanoparticles played important roles in improving the photoelectrochemical performance of TNT-Au films. Moreover, in this work, both sides of TNT-Au films were researched and compared owing to theirs semitransparency. It was firstly found that the photoelectric activity of TNT-Au composite films with back-side illumination was obviously superior to front-side illumination.

Preparation of explosive nanoparticles in a porous chromium(III) oxide matrix: a first attempt to control the reactivity of explosives

Energy Technology Data Exchange (ETDEWEB)

Comet, M; Siegert, B; Pichot, V; Gibot, P; Spitzer, D [Laboratoire ISL/CNRS ' Nanomateriaux pour les Systemes Sous Sollicitations Extremes' (NS3E), FRE 3026, French-German Research Institute of Saint-Louis (ISL), 5 rue du General Cassagnou, 68301 Saint-Louis (France)], E-mail: comet@isl.tm.fr

2008-07-16

This paper reports the first attempt to control the combustion and the detonation properties of a high explosive through its structure. A porous chromium(III) oxide matrix produced by the combustion of ammonium dichromate was infiltrated by hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). The structure of the Cr{sub 2}O{sub 3} matrix was studied by both scanning and transmission electron microscopy (SEM, TEM); the Cr{sub 2}O{sub 3}/RDX nanocomposites were characterized by nitrogen adsorption. A mathematical model based on these techniques was used to demonstrate that the Cr{sub 2}O{sub 3} matrix encloses and stabilizes RDX particles at the nanoscale. The decomposition process of the nanocomposites was investigated by atomic force microscopy (AFM). The reactivity and sensitivity of the nanocomposites were studied by impact and friction tests, differential scanning calorimetry (DSC), time-resolved cinematography and detonation experiments, and were correlated with their structure. The size of RDX nanoparticles and their distribution in the Cr{sub 2}O{sub 3} matrix have an important influence on their reactivity. The reactive properties of nanostructured RDX differ significantly from those of classical micron-sized RDX. For instance, the melting point disappears and the decomposition temperature is significantly lowered. The quantization of the explosive particles in the Cr{sub 2}O{sub 3} matrix decreases the sensitivity to mechanical stress and allows controlling the decomposition mode-i.e. combustion versus detonation.

2,4,6-Trinitrotoluene mineralization and bacterial production rates of natural microbial assemblages from coastal sediments

International Nuclear Information System (INIS)

Montgomery, Michael T.; Coffin, Richard B.; Boyd, Thomas J.; Smith, Joseph P.; Walker, Shelby E.; Osburn, Christopher L.

2011-01-01

The nitrogenous energetic constituent, 2,4,6-Trinitrotoluene (TNT), is widely reported to be resistant to bacterial mineralization (conversion to CO 2 ); however, these studies primarily involve bacterial isolates from freshwater where bacterial production is typically limited by phosphorus. This study involved six surveys of coastal waters adjacent to three biome types: temperate broadleaf, northern coniferous, and tropical. Capacity to catabolize and mineralize TNT ring carbon to CO 2 was a common feature of natural sediment assemblages from these coastal environments (ranging to 270+/-38 μg C kg -1 d -1 ). More importantly, these mineralization rates comprised a significant proportion of total heterotrophic production. The finding that most natural assemblages surveyed from these ecosystems can mineralize TNT ring carbon to CO 2 is consistent with recent reports that assemblage components can incorporate TNT ring carbon into bacterial biomass. These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments. - Highlights: → TNT mineralization is a common feature of natural bacterial assemblages in coastal sediments. → TNT mineralization rates comprised a significant proportion of total heterotrophic production. → These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments. - The capacity to mineralize TNT ring carbon to CO 2 is a common feature of natural bacterial assemblages in coastal sediment.

15N NMR investigation of the covalent binding of reduced TNT amines to soil humic acid, model compounds, and lignocellulose

Science.gov (United States)

Thorn, K.A.; Kennedy, K.R.

2002-01-01

The five major reductive degradation products of TNT-4ADNT (4-amino-2,6-dinitrotoluene), 2ADNT (2-amino-4,6-dinitrotoluene), 2,4DANT (2,4-diamino-6-nitrotoluene), 2,6DANT (2,6-diamino-4-nitrotoluene), and TAT (2,4,6-triaminotoluene)-labeled with 15N in the amine positions, were reacted with the IHSS soil humic acid and analyzed by 15N NMR spectrometry. In the absence of catalysts, all five amines underwent nucleophilic addition reactions with quinone and other carbonyl groups in the soil humic acid to form both heterocyclic and nonheterocyclic condensation products. Imine formation via 1,2-addition of the amines to quinone groups in the soil humic acid was significant with the diamines and TAT but not the monoamines. Horseradish peroxidase (HRP) catalyzed an increase in the incorporation of all five amines into the humic acid. In the case of the diamines and TAT, HRP also shifted the binding away from heterocyclic condensation product toward imine formation. A comparison of quantitative liquid phase with solid-state CP/MAS 15N NMR indicated that the CP experiment underestimated imine and heterocyclic nitrogens in humic acid, even with contact times optimal for observation of these nitrogens. Covalent binding of the mono- and diamines to 4-methylcatechol, the HRP catalyzed condensation of 4ADNT and 2,4DANT to coniferyl alcohol, and the binding of 2,4DANT to lignocellulose with and without birnessite were also examined.

A thermodynamically based definition of fast verses slow heating in secondary explosives

Science.gov (United States)

Henson, Bryan; Smilowitz, Laura

2013-06-01

The thermal response of energetic materials is often categorized according to the rate of heating as either fast or slow, e.g. slow cook-off. Such categorizations have most often followed some operational rationale, without a material based definition. We have spent several years demonstrating that for the energetic material octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) a single mechanism of thermal response reproduces times to ignition independent of rate or means of heating over the entire range of thermal response. HMX is unique in that bulk melting is rarely observed in either thermal ignition or combustion. We have recently discovered a means of expressing this mechanism for HMX in a reduced form applicable to many secondary explosives. We will show that with this mechanism a natural definition of fast versus slow rates of heating emerges, related to the rate of melting, and we use this to illustrate why HMX does not exhibit melting, and why a number of other secondary explosives do, and require the two separate categories.

Tracing explosive in solvent using quantum cascade laser with pulsed electric discharge system

Energy Technology Data Exchange (ETDEWEB)

Park, Seong-Wook; Tian, Chao; Martini, Rainer, E-mail: rmartini@stevens.edu [Department of Physics and Engineering Physics, Stevens Institute of Technology, 1 Castle Point on Hudson, Hoboken, New Jersey 07030 (United States); Chen, Gang [School of Optoelectronic Engineering, Chongqing University, Chongqing 400044 (China); Chen, I-chun Anderson [Newport Corporation/Oriel Instruments, 150 Long Beach Boulevard, Stratford, Connecticut 06615 (United States)

2014-11-03

We demonstrated highly sensitive detection of explosive dissolved in solvent with a portable spectroscopy system (Q-MACS) by tracing the explosive byproduct, N{sub 2}O, in combination with a pulsed electric discharge system for safe explosive decomposition. Using Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), the gas was monitored and analyzed by Q-MACS and the presence of the dissolved explosive clearly detected. While HMX presence could be identified directly in the air above the solutions even without plasma, much better results were achieved under the decomposition. The experiment results give an estimated detection limit of 10 ppb, which corresponds to a 15 pg of HMX.

Tracing explosive in solvent using quantum cascade laser with pulsed electric discharge system

International Nuclear Information System (INIS)

Park, Seong-Wook; Tian, Chao; Martini, Rainer; Chen, Gang; Chen, I-chun Anderson

2014-01-01

We demonstrated highly sensitive detection of explosive dissolved in solvent with a portable spectroscopy system (Q-MACS) by tracing the explosive byproduct, N 2 O, in combination with a pulsed electric discharge system for safe explosive decomposition. Using Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), the gas was monitored and analyzed by Q-MACS and the presence of the dissolved explosive clearly detected. While HMX presence could be identified directly in the air above the solutions even without plasma, much better results were achieved under the decomposition. The experiment results give an estimated detection limit of 10 ppb, which corresponds to a 15 pg of HMX

Electrochemical reduction of trinitrotoluene on core-shell tin-carbon electrodes

International Nuclear Information System (INIS)

Grigoriants, Irena; Markovsky, Boris; Persky, Rachel; Perelshtein, Ilana; Gedanken, Aharon; Aurbach, Doron; Filanovsky, Boris; Bourenko, Tatiana; Felner, Israel

2008-01-01

In this work, we studied the electrochemical process of 2,4,6-trinitrotoluene (TNT) reduction on a new type of electrodes based on a core-shell tin-carbon Sn(C) structure. The Sn(C) composite was prepared from the precursor tetramethyl-tin Sn(CH 3 ) 4 , and the product contained a core of submicron-sized tin particles uniformly enveloped with carbon shells. Cyclic voltammograms of Sn(C) electrodes in aqueous sodium chloride solutions containing TNT show three well-pronounced reduction waves in the potential range of -0.50 to -0.80 V (vs. an Ag/AgCl/Cl - reference electrode) that correspond to the multistep process of TNT reduction. Electrodes containing Sn(C) particles annealed at 800 deg. C under argon develop higher voltammetric currents of TNT reduction (comparing to the as-prepared tin-carbon material) due to stabilization of the carbon shell. It is suggested that the reduction of TNT on core-shell tin-carbon electrodes is an electrochemically irreversible process. A partial oxidation of the TNT reduction products occurred at around -0.20 V. The electrochemical response of TNT reduction shows that it is not controlled by the diffusion of the active species to/from the electrodes but rather by interfacial charge transfer and possible adsorption phenomena. The tin-carbon electrodes demonstrate significantly stable behavior for TNT reduction in NaCl solutions and provide sufficient reproducibility with no surface fouling through prolonged voltammetric cycling. It is presumed that tin nanoparticles, which constitute the core, are electrochemically inactive towards TNT reduction, but Sn or SnO 2 formed on the electrodes during TNT reduction may participate in this reaction as catalysts or carbon-modifying agents. The nitro-groups of TNT can be reduced irreversibly (via two possible paths) by three six-electron transfers, to 2,4,6-triaminotoluene, as follows from mass-spectrometric studies. The tin-carbon electrodes described herein may serve as amperometric sensors

Comparison of Post-detonation Combustion in Explosives Incorporating Aluminum Nanoparticles: Influence of the Passivation Layer (Postprint)

Science.gov (United States)

2013-01-31

meters away from the explosive charge. The collection optic were aligned to view the center of each charge through a BK7 glass view- port. The...Basler Sprint ) with a data collection rate of 1–70 kHz. The resolution and usable spectral range of the spectrograph were 1.2 nm and 380–720 nm...RDX 20 wt. % AlOA in RDX 20 wt. % AlFA in RDX 0 … … … 15 … 4000 ( 400 ) … 30 3900 (200) 4500 (500) 3200 (300) 45 3600 (300) 򓇨 3400 (500) 044907-3

Microstructural and Photoelectrochemical Properties of Gap-TiO2 Nano tubes

International Nuclear Information System (INIS)

Asma Husin Milad; Wan Ramli Daud; Asma Husin Milad; Wan Ramli Daud

2011-01-01

GaP/ TiO 2 / Ti arrays have been prepared via anodization of Ti foil and electrodeposition of GaP. TiO 2 nano tubes (TNT) were grown from a Ti foil by direct anodic oxidation using 0.5M phosphoric acid and 0.14 M NaF as electrolyte at 20 V for 45 min. Various concentrations aqueous solution of Ga(NO 3 ) 3 were used to deposit GaP nanoparticles onto the TNT in the electrodeposition step. Morphology and microstructure of GaP/ TNT were investigated by FESEM and XRD techniques. In addition the photocurrent of the GaP/ TNT were also investigated. It was found that the amount of GaP deposited on TNT considerably improved the efficiency of TNT as photo anode for photoelectrochemical applications. (author)

Initial Reductive Reactions in Aerobic Microbial Metabolism of 2,4,6-Trinitrotoluene

National Research Council Canada - National Science Library

Vorbeck, Claudia

1998-01-01

.... Thus, two bacterial strains enriched with TNT as a sole source of nitrogen under aerobic conditions, a gram-negative strain called TNT-8 and a gram-positive strain called TNT-32, carried out nitro-group reduction...

2,4,6-Trinitrotoluene mineralization and bacterial production rates of natural microbial assemblages from coastal sediments

Energy Technology Data Exchange (ETDEWEB)

Montgomery, Michael T., E-mail: michael.montgomery@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Coffin, Richard B., E-mail: richard.coffin@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Boyd, Thomas J., E-mail: thomas.boyd@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Smith, Joseph P., E-mail: joseph.smith@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Walker, Shelby E., E-mail: Shelby.Walker@noaa.gov [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Osburn, Christopher L., E-mail: chris_osburn@ncsu.edu [Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695 (United States)

2011-12-15

The nitrogenous energetic constituent, 2,4,6-Trinitrotoluene (TNT), is widely reported to be resistant to bacterial mineralization (conversion to CO{sub 2}); however, these studies primarily involve bacterial isolates from freshwater where bacterial production is typically limited by phosphorus. This study involved six surveys of coastal waters adjacent to three biome types: temperate broadleaf, northern coniferous, and tropical. Capacity to catabolize and mineralize TNT ring carbon to CO{sub 2} was a common feature of natural sediment assemblages from these coastal environments (ranging to 270+/-38 {mu}g C kg{sup -1} d{sup -1}). More importantly, these mineralization rates comprised a significant proportion of total heterotrophic production. The finding that most natural assemblages surveyed from these ecosystems can mineralize TNT ring carbon to CO{sub 2} is consistent with recent reports that assemblage components can incorporate TNT ring carbon into bacterial biomass. These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments. - Highlights: > TNT mineralization is a common feature of natural bacterial assemblages in coastal sediments. > TNT mineralization rates comprised a significant proportion of total heterotrophic production. > These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments. - The capacity to mineralize TNT ring carbon to CO{sub 2} is a common feature of natural bacterial assemblages in coastal sediment.

GENE EXPRESSION CHANGES IN ARABIDOPSIS THALIANA SEEDLING ROOTS EXPOSED TO THE MUNITION HEXAHYDRO-1,3,5-TRINITRO-1,3,5-TRIAZINE

Science.gov (United States)

Arabidopsis thaliana root transcriptome responses to the munition, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), were assessed using serial analysis of gene expression (SAGE). Comparison of the transcriptional profile for the RDX response to a profile previously described for Ar...

High-Sensitivity Troponin: A Clinical Blood Biomarker for Staging Cardiomyopathy in Fabry Disease.

Science.gov (United States)

Seydelmann, Nora; Liu, Dan; Krämer, Johannes; Drechsler, Christiane; Hu, Kai; Nordbeck, Peter; Schneider, Andreas; Störk, Stefan; Bijnens, Bart; Ertl, Georg; Wanner, Christoph; Weidemann, Frank

2016-05-31

High-sensitivity troponin (hs-TNT), a biomarker of myocardial damage, might be useful for assessing fibrosis in Fabry cardiomyopathy. We performed a prospective analysis of hs-TNT as a biomarker for myocardial changes in Fabry patients and a retrospective longitudinal follow-up study to assess longitudinal hs-TNT changes relative to fibrosis and cardiomyopathy progression. For the prospective analysis, hs-TNT from 75 consecutive patients with genetically confirmed Fabry disease was analyzed relative to typical Fabry-associated echocardiographic findings and total myocardial fibrosis as measured by late gadolinium enhancement (LE) on magnetic resonance imaging. Longitudinal data (3.9±2.0 years), including hs-TNT, LE, and echocardiographic findings from 58 Fabry patients, were retrospectively collected. Hs-TNT level positively correlated with LE (linear correlation coefficient, 0.72; odds ratio, 32.81 [95% CI, 3.56-302.59]; P=0.002); patients with elevated baseline hs-TNT (>14 ng/L) showed significantly increased LE (median: baseline, 1.9 [1.1-3.3] %; follow-up, 3.2 [2.3-4.9] %; PFabry disease and a qualified predictor of cardiomyopathy progression. Thus, hs-TNT could be helpful for staging and follow-up of Fabry patients. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Effect of organic additives on the mitigation of volatility of 1-nitro-3,3'-dinitroazetidine (TNAZ): Next generation powerful melt cast able high energy material

International Nuclear Information System (INIS)

Talawar, M.B.; Singh, Alok; Naik, N.H.; Polke, B.G.; Gore, G.M.; Asthana, S.N.; Gandhe, B.R.

2006-01-01

1-Nitro-3,3'-dinitroazetidine (TNAZ) was synthesized based on the lines of reported method. Thermolysis studies on synthesized and characterized TNAZ using differential scanning calorimetry (DSC) and hyphenated TG-FT-IR techniques were undertaken to generate data on decomposition pattern. FT-IR of decomposition products of TNAZ revealed the evolution of oxides of nitrogen and HCN containing species suggesting the cleavage of C/N-NO 2 bond accompanied with the collapse of ring structure. The effect of incorporation of 15% additives namely, 3-amino-1,2,4-triazole (AT), 3,5-diamino-1,2,4-triazole (DAT), carbohydrazide (CHZ), 5,7-dinitrobenzofuroxan (DNBF), bis (2,2-dinitropropyl) succinate (BNPS), triaminoguanidinium nitrate (TAGN), 2,4,6-trinitrobenzoic acid (TNBA) and nitroguanidine (NQ) on the volatility of TNAZ was investigated by undertaking thermogravimetric analysis. The TG pattern brings out the potential of BNPS and TAGN as additives to mitigate the volatility of TNAZ. The influence of additives on thermal decomposition of pattern of TNAZ was also investigated by DSC. The DSC results indicated that the additives did not have appreciable effect on the melting point of TNAZ. Scanning electron microscopic (SEM) studies were carried out to investigate the effect of additives on morphology of TNAZ. This paper also discusses the possible mechanism involved in between the TNAZ and TAGN and BNPS. It appears that the formation of charge transfer complex formation between the TNAZ and TAGN/BNPS. The effect of addition of high explosives such as CL-20, HMX and RDX on thermo-physical characteristics of TNAZ is also reported in this paper

The tensor network theory library

Science.gov (United States)

Al-Assam, S.; Clark, S. R.; Jaksch, D.

2017-09-01

In this technical paper we introduce the tensor network theory (TNT) library—an open-source software project aimed at providing a platform for rapidly developing robust, easy to use and highly optimised code for TNT calculations. The objectives of this paper are (i) to give an overview of the structure of TNT library, and (ii) to help scientists decide whether to use the TNT library in their research. We show how to employ the TNT routines by giving examples of ground-state and dynamical calculations of one-dimensional bosonic lattice system. We also discuss different options for gaining access to the software available at www.tensornetworktheory.org.

High?Sensitivity Troponin: A Clinical Blood Biomarker for Staging Cardiomyopathy in Fabry Disease

OpenAIRE

2016-01-01

Background High?sensitivity troponin (hs?TNT), a biomarker of myocardial damage, might be useful for assessing fibrosis in Fabry cardiomyopathy. We performed a prospective analysis of hs?TNT as a biomarker for myocardial changes in Fabry patients and a retrospective longitudinal follow?up study to assess longitudinal hs?TNT changes relative to fibrosis and cardiomyopathy progression. Methods and Results For the prospective analysis, hs?TNT from 75 consecutive patients with genetically confirm...

Some analytical methods for explosives: Part 2

Energy Technology Data Exchange (ETDEWEB)

Selig, W.

1965-12-08

This report is the second compilation of methods for analyzing explosives. All the methods were developed for routine performance by techniques, and an attempt has therefore been made to keep them as simple as possible. Methods are presented for analyzing plastic-bonded explosives based on sym-cyclomethylenetetra-nitramine (HMX), based on viton in addition to HMX, and based on pentraerythritol tetranitrate (PETN).

Patterning high explosives at the nanoscale

Energy Technology Data Exchange (ETDEWEB)

Nafday, Omkar A.; Pitchimani, Rajasekar; Weeks, Brandon L. [Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409 (United States); Haaheim, Jason [NanoInk Inc., 8025 Lamon Ave., Skokie, IL 60077 (United States)

2006-10-15

For the first time, we have shown that spin coating and Dip pen nanolithography (DPN trademark) are simple methods of preparing energetic materials such as PETN and HMX on the nanoscale, requiring no heating of the energetic material. Nanoscale patterning has been demonstrated by the DPN method while continuous thin films were produced using the spin coating method. Results are presented for preparing continuous PETN thin films of nanometer thickness by the spin coating method and for controlling the architecture of arbitrary nanoscale patterns of PETN and HMX by the DPN method. These methods are simple for patterning energetic materials and can be extended beyond PETN and HMX, opening the door for fundamental studies at the nanoscale. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

In situ pilot test for bioremediation of energetic compound-contaminated soil at a former military demolition range site.

Science.gov (United States)

Jugnia, Louis B; Manno, Dominic; Drouin, Karine; Hendry, Meghan

2018-05-04

Bioremediation was performed in situ at a former military range site to assess the performance of native bacteria in degrading hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4-dinitrotoluene (2,4-DNT). The fate of these pollutants in soil and soil pore water was investigated as influenced by waste glycerol amendment to the soil. Following waste glycerol application, there was an accumulation of organic carbon that promoted microbial activity, converting organic carbon into acetate and propionate, which are intermediate compounds in anaerobic processes. This augmentation of anaerobic activity strongly correlated to a noticeable reduction in RDX concentrations in the amended soil. Changes in concentrations of RDX in pore water were similar to those observed in the soil suggesting that RDX leaching from the soil matrix, and treatment with waste glycerol, contributed to the enhanced removal of RDX from the water and soil. This was not the case with 2,4-DNT, which was neither found in pore water nor affected by the waste glycerol treatment. Results from saturated conditions and Synthetic Precipitation Leaching Procedure testing, to investigate the environmental fate of 2,4-DNT, indicated that 2,4-DNT found on site was relatively inert and was likely to remain in its current state on the site.

Selective fluorescence response and magnetic separation probe for 2,4,6-trinitrotoluene based on iron oxide magnetic nanoparticles.

Science.gov (United States)

Zou, Wen-Sheng; Wang, Ya-Qin; Wang, Feng; Shao, Qun; Zhang, Jun; Liu, Jin

2013-05-01

Despite the rapid development of nanomaterials and nanotechnology, it is still desirable to develop novel nanoparticle-based techniques which are cost-effective, timesaving, and environment-friendly, and with ease of operation and procedural simplicity, for assay of target analytes. In the work discussed in this paper, the dye fluorescein isothiocyanate (FITC) was conjugated to 1,6-hexanediamine (HDA)-capped iron oxide magnetic nanoparticles (FITC-HDA Fe3O4 MNPs), and the product was characterized. HDA ligands on the surface of Fe3O4 MNPs can bind 2,4,6-trinitrotoluene (TNT) to form TNT anions by acid-base pairing interaction. Formation of TNT anions, and captured TNT substantially affect the emission of FITC on the surface of the Fe3O4 MNPs, resulting in quenching of the fluorescence at 519 nm. A novel FITC-HDA Fe3O4 MNPs-based probe featuring chemosensing and magnetic separation has therefore been constructed. i.e. FITC-HDA Fe3O4 MNPs had a highly selective fluorescence response and enabled magnetic separation of TNT from other nitroaromatic compounds by quenching of the emission of FITC and capture of TNT in aqueous solution. Very good linearity was observed for TNT concentrations in the range 0.05-1.5 μmol L(-1), with a detection limit of 37.2 nmol L(-1) and RSD of 4.7 % (n = 7). Approximately 12 % of the total amount of TNT was captured. The proposed methods are well-suited to trace detection and capture of TNT in aqueous solution.

Measurement of the flow properties within a copper tube containing a deflagrating explosive

Energy Technology Data Exchange (ETDEWEB)

Hill, Larry G [Los Alamos National Laboratory; Morris, John S [Los Alamos National Laboratory; Jackson, Scott I [Los Alamos National Laboratory

2009-01-01

We report on the propagation of deflagration waves in the high explosive (HE) PBX 9501 (95 wt % HMX, 5 wt% binder). Our test configuration, which we call the def1agration cylinder test (DFCT), is fashioned after the detonation cylinder test (DTCT) that is used to calibrate the JWL detonation product equation of state (EOS). In the DFCT, the HE is heated to a uniform slightly subcritical temperature, and is ignited at one end by a hot wire. For some configurations and initial conditions, we observe a quasi-steady wave that flares the tube into a funnel shape, stretching it to the point of rupture. This behavior is qualitatively like the DTCT, such that, by invoking certain additional approximations that we discuss, its behavior can be analyzed by the same methods. We employ an analysis proposed by G.I. Taylor to infer the pressure-volume curve for the burning, expanding flow. By comparing this result to the EOS of HMX product gas alone. we infer that only {approx}20 wt% of the HMX has burned at tube rupture. This result confirms pre-existing observations about the role of convective burning in HMX cookoff explosions.

Fabrication of transparent TiO2 nanotube-based photoanodes for CdS/CdTe quantum co-sensitized solar cells

Science.gov (United States)

Gualdrón-Reyes, A. F.; Cárdenas-Arenas, A.; Martínez, C. A.; Kouznetsov, V. V.; Meléndez, A. M.

2017-01-01

In order to fabricate a solar cell, ordered TiO2 nanotube (TNT) arrays were prepared by double anodization. TNT arrays with variable lengths were obtained by changing the duration of the anodizing process of up to 3h. TNT membranes were transferred to indium tin oxide substrates and attached with a B-TiO2 sol. TNT photoanode with the best photoelectrochemical performance was sensitized with CdS by SILAR method. On other hand, CdTe quantum dots prepared via colloidal synthesis were deposited on TNT photoanodes for 2h, 4h and 6h. In addition, TNT/CdS was loaded with CdTe quantum dots for 4 h. Morphology and chemical modification of TiO2 were characterized by FESEM and XPS, while their photoelectrochemical performance was measured by open-circuit photopotential and photovoltammetry under visible light. TiO2 nanotubes grown during 2.5h showed the highest photocurrent due to presence of Ti3+ donor states by N and F co-doping, increasing the number of photogenerated electrons transported to back collector. TNT/CdS/CdTe photoanode reach the highest conversion efficiency under AM 1.5G simulated solar illumination.

Formulation, Casting, and Evaluation of Paraffin-Based Solid Fuels Containing Energetic and Novel Additives for Hybrid Rockets

Science.gov (United States)

Larson, Daniel B.; Desain, John D.; Boyer, Eric; Wachs, Trevor; Kuo, Kenneth K.; Borduin, Russell; Koo, Joseph H.; Brady, Brian B.; Curtiss, Thomas J.; Story, George

2012-01-01

This investigation studied the inclusion of various additives to paraffin wax for use in a hybrid rocket motor. Some of the paraffin-based fuels were doped with various percentages of LiAlH4 (up to 10%). Addition of LiAlH4 at 10% was found to increase regression rates between 7 - 10% over baseline paraffin through tests in a gaseous oxygen hybrid rocket motor. Mass burn rates for paraffin grains with 10% LiAlH4 were also higher than those of the baseline paraffin. RDX was also cast into a paraffin sample via a novel casting process which involved dissolving RDX into dimethylformamide (DMF) solvent and then drawing a vacuum on the mixture of paraffin and RDX/DMF in order to evaporate out the DMF. It was found that although all DMF was removed, the process was not conducive to generating small RDX particles. The slow boiling generated an inhomogeneous mixture of paraffin and RDX. It is likely that superheating the DMF to cause rapid boiling would likely reduce RDX particle sizes. In addition to paraffin/LiAlH4 grains, multi-walled carbon nanotubes (MWNT) were cast in paraffin for testing in a hybrid rocket motor, and assorted samples containing a range of MWNT percentages in paraffin were imaged using SEM. The fuel samples showed good distribution of MWNT in the paraffin matrix, but the MWNT were often agglomerated, indicating that a change to the sonication and mixing processes were required to achieve better uniformity and debundled MWNT. Fuel grains with MWNT fuel grains had slightly lower regression rate, likely due to the increased thermal conductivity to the fuel subsurface, reducing the burning surface temperature.

Formulation and Testing of Paraffin-Based Solid Fuels Containing Energetic Additives for Hybrid Rockets

Science.gov (United States)

Larson, Daniel B.; Boyer, Eric; Wachs,Trevor; Kuo, Kenneth K.; Story, George

2012-01-01

Many approaches have been considered in an effort to improve the regression rate of solid fuels for hybrid rocket applications. One promising method is to use a fuel with a fast burning rate such as paraffin wax; however, additional performance increases to the fuel regression rate are necessary to make the fuel a viable candidate to replace current launch propulsion systems. The addition of energetic and/or nano-sized particles is one way to increase mass-burning rates of the solid fuels and increase the overall performance of the hybrid rocket motor.1,2 Several paraffin-based fuel grains with various energetic additives (e.g., lithium aluminum hydride (LiAlH4) have been cast in an attempt to improve regression rates. There are two major advantages to introducing LiAlH4 additive into the solid fuel matrix: 1) the increased characteristic velocity, 2) decreased dependency of Isp on oxidizer-to-fuel ratio. The testing and characterization of these solid-fuel grains have shown that continued work is necessary to eliminate unburned/unreacted fuel in downstream sections of the test apparatus.3 Changes to the fuel matrix include higher melting point wax and smaller energetic additive particles. The reduction in particle size through various methods can result in more homogeneous grain structure. The higher melting point wax can serve to reduce the melt-layer thickness, allowing the LiAlH4 particles to react closer to the burning surface, thus increasing the heat feedback rate and fuel regression rate. In addition to the formulation of LiAlH4 and paraffin wax solid-fuel grains, liquid additives of triethylaluminum and diisobutylaluminum hydride will be included in this study. Another promising fuel formulation consideration is to incorporate a small percentage of RDX as an additive to paraffin. A novel casting technique will be used by dissolving RDX in a solvent to crystallize the energetic additive. After dissolving the RDX in a solvent chosen for its compatibility

Are TiO2 nanotubes worth using in photocatalytic purification of air and water?

Science.gov (United States)

Pichat, Pierre

2014-09-19

Titanium dioxide nanotubes (TNT) have mainly been used in dye sensitized solar cells, essentially because of a higher transport rate of electrons from the adsorbed photo-excited dye to the Ti electrode onto which TNT instead of TiO2 nanoparticles (TNP) are attached. The dimension ranges and the two main synthesis methods of TNT are briefly indicated here. Not surprisingly, the particular and regular texture of TNT was also expected to improve the photocatalytic efficacy for pollutant removal in air and water with respect to TNP. In this short review, the validity of this expectation is checked using the regrettably small number of literature comparisons between TNT and commercialized TNP referring to films of similar thickness and layers or slurries containing an equal TiO2 mass. Although the irradiated geometrical area differed for each study, it was identical for each comparison considered here. For the removal of toluene (methylbenzene) or acetaldehyde (ethanal) in air, the average ratio of the efficacy of TNT over that of TiO2 P25 was about 1.5, and for the removal of dyes in water, it was around 1. This lack of major improvement with TNT compared to TNP could partially be due to TNT texture disorders as seems to be suggested by the better average performance of anodic oxidation-prepared TNT. It could also come from the fact that the properties influencing the efficacy are more numerous, their interrelations more complex and their effects more important for pollutant removal than for dye sensitized solar cells and photoelectrocatalysis where the electron transport rate is the crucial parameter.

The Indian Jihadist Movement: Evolution and Dynamics

Science.gov (United States)

2014-07-01

and friendship ties.78 In some instances, a person is exposed to the proper “mood music ,” decides he wants to “do” jihad, and looks for assistance...Brigade RDX smuggled from Bangladesh Diwali Festival , Delhi October 29, 2005 IM–Northern Brigade RDX smuggled from Bangladesh; Lashkar-e-Taiba

Visual detection of 2,4,6-trinitrotolune by molecularly imprinted colloidal array photonic crystal

International Nuclear Information System (INIS)

Lu, Wei; Asher, Sanford A.; Meng, Zihui; Yan, Zequn; Xue, Min; Qiu, Lili; Yi, Da

2016-01-01

Graphical abstract: Molecularly imprinted colloidal array (MICA) was explored for the selective visual detection of TNT with color changing from green to red. And molecularly imprinted colloidal particles (MICs) were evaluated for the adsorption capacity and the imprinting efficiency. The MICA had excellent flexibility, reversibility and stability. It promised high potential for the visual semi-quantitative detection of other explosives. - Highlights: • Molecularly imprinted colloidal array (MICA) was used to visually detect TNT. • The relationship of particle size, diffracted wavelength and color was discussed. • The adsorption capacity and imprinting efficiency of MICs were calculated. • MICA had short response time, high selectivity, good reversibility and stability. • MICA had high potential to be used in other customed visual explosive detection. - Abstract: We developed a photonic crystal (PhC) sensor for the quantification of 2,4,6-trinitrotoluene (TNT) in solution. Monodisperse (210 nm in diameter) molecularly imprinted colloidal particles (MICs) for TNT were prepared by the emulsion polymerization of methyl methacrylate and acrylamide in the presence of TNT as a template. The MICs were then self-assembled into close-packed opal PhC films. The adsorption capacity of the MICs for TNT was 64 mg TNT/g. The diffraction from the PhC depended on the TNT concentration in a methanol/water (3/2, v/v) potassium dihydrogen phosphate buffer solution (pH = 7.0, 30 mM). The limit of detection (LOD) of the sensor was 1.03 μg. The color of the molecularly imprinted colloidal array (MICA) changed from green to red with an 84 nm diffraction red shift when the TNT concentration increased to 20 mM. The sensor response time was 3 min. The PhC sensor was selective for TNT compared to similar compounds such as 2,4,6-trinitrophenol, 2,4-dinitrotoluene, 2,6-dinitrotoluene, 2-nitromesitylene, 4-nitrotoluene, 2-nitrotoluene, 1,3-dinitrobenzene, methylbenzene, 4-nitrophenol

Visual detection of 2,4,6-trinitrotolune by molecularly imprinted colloidal array photonic crystal

Energy Technology Data Exchange (ETDEWEB)

Lu, Wei [School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing, 100081 (China); Asher, Sanford A., E-mail: asher@pitt.edu [Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Meng, Zihui, E-mail: m_zihui@yahoo.com [School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing, 100081 (China); Yan, Zequn [School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing, 100081 (China); Xue, Min, E-mail: minxue@bit.edu.cn [School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing, 100081 (China); Qiu, Lili, E-mail: qiulili@bit.edu.cn [School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing, 100081 (China); Yi, Da [School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing, 100081 (China)

2016-10-05

Graphical abstract: Molecularly imprinted colloidal array (MICA) was explored for the selective visual detection of TNT with color changing from green to red. And molecularly imprinted colloidal particles (MICs) were evaluated for the adsorption capacity and the imprinting efficiency. The MICA had excellent flexibility, reversibility and stability. It promised high potential for the visual semi-quantitative detection of other explosives. - Highlights: • Molecularly imprinted colloidal array (MICA) was used to visually detect TNT. • The relationship of particle size, diffracted wavelength and color was discussed. • The adsorption capacity and imprinting efficiency of MICs were calculated. • MICA had short response time, high selectivity, good reversibility and stability. • MICA had high potential to be used in other customed visual explosive detection. - Abstract: We developed a photonic crystal (PhC) sensor for the quantification of 2,4,6-trinitrotoluene (TNT) in solution. Monodisperse (210 nm in diameter) molecularly imprinted colloidal particles (MICs) for TNT were prepared by the emulsion polymerization of methyl methacrylate and acrylamide in the presence of TNT as a template. The MICs were then self-assembled into close-packed opal PhC films. The adsorption capacity of the MICs for TNT was 64 mg TNT/g. The diffraction from the PhC depended on the TNT concentration in a methanol/water (3/2, v/v) potassium dihydrogen phosphate buffer solution (pH = 7.0, 30 mM). The limit of detection (LOD) of the sensor was 1.03 μg. The color of the molecularly imprinted colloidal array (MICA) changed from green to red with an 84 nm diffraction red shift when the TNT concentration increased to 20 mM. The sensor response time was 3 min. The PhC sensor was selective for TNT compared to similar compounds such as 2,4,6-trinitrophenol, 2,4-dinitrotoluene, 2,6-dinitrotoluene, 2-nitromesitylene, 4-nitrotoluene, 2-nitrotoluene, 1,3-dinitrobenzene, methylbenzene, 4-nitrophenol

Recognition of explosives fingerprints on objects for courier services using machine learning methods and laser-induced breakdown spectroscopy.

Science.gov (United States)

Moros, J; Serrano, J; Gallego, F J; Macías, J; Laserna, J J

2013-06-15

During recent years laser-induced breakdown spectroscopy (LIBS) has been considered one of the techniques with larger ability for trace detection of explosives. However, despite of the high sensitivity exhibited for this application, LIBS suffers from a limited selectivity due to difficulties in assigning the molecular origin of the spectral emissions observed. This circumstance makes the recognition of fingerprints a latent challenging problem. In the present manuscript the sorting of six explosives (chloratite, ammonal, DNT, TNT, RDX and PETN) against a broad list of potential harmless interferents (butter, fuel oil, hand cream, olive oil, …), all of them in the form of fingerprints deposited on the surfaces of objects for courier services, has been carried out. When LIBS information is processed through a multi-stage architecture algorithm built from a suitable combination of 3 learning classifiers, an unknown fingerprint may be labeled into a particular class. Neural network classifiers trained by the Levenberg-Marquardt rule were decided within 3D scatter plots projected onto the subspace of the most useful features extracted from the LIBS spectra. Experimental results demonstrate that the presented algorithm sorts fingerprints according to their hazardous character, although its spectral information is virtually identical in appearance, with rates of false negatives and false positives not beyond of 10%. These reported achievements mean a step forward in the technology readiness level of LIBS for this complex application related to defense, homeland security and force protection. Copyright © 2013 Elsevier B.V. All rights reserved.

Improvement in energy release properties of boron-based propellant by oxidant coating

Energy Technology Data Exchange (ETDEWEB)

Liang, Daolun; Liu, Jianzhong, E-mail: jzliu@zju.edu.cn; Chen, Binghong; Zhou, Junhu; Cen, Kefa

2016-08-20

Highlights: • NH{sub 4}ClO{sub 4}, KNO{sub 3}, KClO{sub 4} and HMX coated B were used to prepare propellant samples. • FTIR, XRD and SEM were used for the microstructure analysis of the prepared B. • Thermal oxidation and combustion characteristics of the propellants were studied. • HMX coating was the most beneficial to the energy release of the samples. - Abstract: The energy release properties of a propellant can be improved by coating boron (B) particles with oxidants. In the study, B was coated with four different oxidants, namely, NH{sub 4}ClO{sub 4}, KNO{sub 3}, LiClO{sub 4}, and cyclotetramethylenetetranitramine (HMX), and the corresponding propellant samples were prepared. First, the structural and morphological analyses of the pretreated B were carried out. Then, the thermal analysis and laser ignition experiments of the propellant samples were carried out. Coating with NH{sub 4}ClO{sub 4} showed a better performance than mechanical mixing with the same component. Coating with KNO{sub 3} efficiently improved the ignition characteristics of the samples. Coating with LiClO{sub 4} was the most beneficial in reducing the degree of difficulty of B oxidation. Coating with HMX was the most beneficial in the heat release of the samples. The KNO{sub 3}-coated sample had a very high combustion intensity in the beginning, but then it rapidly became weak. Large amounts of sparks were ejected during the combustion of the LiClO{sub 4}-coated sample. The HMX-coated sample had the longest self-sustaining combustion time (4332 ms) and the highest average combustion temperature (1163.92 °C).

Fabrication of titanate nanotubes/iron oxide magnetic composite for the high efficient capture of radionuclides: a case investigation of 109Cd(II)

International Nuclear Information System (INIS)

Lei Dai; Jun Zheng; Lijie Wang

2013-01-01

In this paper, the capture of radiocadmium (Cd(II)) by adsorption onto the titanate nanotube/iron oxide (TNT/IOM) magnetic composite as a function of contact time, pH, ionic strength, foreign cation and anion ions, humic acid (HA) and fulvic acid (FA) was studied using batch technique. The results indicated that the adsorption of Cd(II) onto the TNT/IOM magnetic composite was dependent on ionic strength at pH 9.0. Outer-sphere surface complexation were the main mechanism of Cd(II) adsorption onto the TNT/IOM magnetic composite at low pH values, whereas the adsorption was mainly dominated via inner-sphere surface complexation at high pH values. The adsorption of Cd(II) onto the TNT/IOM magnetic composite was dependent on foreign cation and anion ions at low pH values, but was independent of foreign cation and anion ions at high pH values. A positive effect of HA/FA on Cd(II) adsorption onto the TNT/IOM magnetic composite was found at low pH values, while a negative effect was observed at high pH values. From the results of Cd(II) removal by the TNT/IOM magnetic composite, the optimum reaction conditions can be obtained for the maximum removal of Cd(II) from water. It is clear that the best pH values of the system to remove Cd(II) from solution by using the TNT/IOM magnetic composite are 7.0-8.0. Considering the low cost and effective disposal of Cd(II)-contaminated wastewaters, the best condition for Cd(II) capture by the TNT/IOM magnetic composite is at room temperature and solid content of 0.5 g L -1 . These results are quite important for estimating and optimizing the removal of Cd(II) and related metal ions by the TNT-based magnetic composite. (author)

Pilot Integration of HIV Screening and Healthcare Settings with Multi- Component Social Network and Partner Testing for HIV Detection.

Science.gov (United States)

Rentz, Michael F; Ruffner, Andrew H; Ancona, Rachel M; Hart, Kimberly W; Kues, John R; Barczak, Christopher M; Lindsell, Christopher J; Fichtenbaum, Carl J; Lyons, Michael S

2017-11-23

Healthcare settings screen broadly for HIV. Public health settings use social network and partner testing ("Transmission Network Targeting (TNT)") to select high-risk individuals based on their contacts. HIV screening and TNT systems are not integrated, and healthcare settings have not implemented TNT. The study aimed to evaluate pilot implementation of multi-component, multi-venue TNT in conjunction with HIV screening by a healthcare setting. Our urban, academic health center implemented a TNT program in collaboration with the local health department for five months during 2011. High-risk or HIV positive patients of the infectious diseases clinic and emergency department HIV screening program were recruited to access social and partner networks via compensated peer-referral, testing of companions present with them, and partner notification services. Contacts became the next-generation index cases in a snowball recruitment strategy. The pilot TNT program yielded 485 HIV tests for 482 individuals through eight generations of recruitment with five (1.0%; 95% CI = 0.4%, 2.3%) new diagnoses. Of these, 246 (51.0%; 95% CI = 46.6%, 55.5%) reported that they had not been tested for HIV within the last 12 months and 383 (79.5%; 95% CI = 75.7%, 82.9%) had not been tested by the existing ED screening program within the last five years. TNT complements population screening by more directly targeting high-risk individuals and by expanding the population receiving testing. Information from existing healthcare services could be used to seed TNT programs, or TNT could be implemented within healthcare settings. Research evaluating multi-component, multi-venue HIV detection is necessary to maximize complementary approaches while minimizing redundancy. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Toward Improved Fidelity of Thermal Explosion Simulations

Energy Technology Data Exchange (ETDEWEB)

Nichols, A L; Becker, R; Howard, W M; Wemhoff, A

2009-07-17

We will present results of an effort to improve the thermal/chemical/mechanical modeling of HMX based explosive like LX04 and LX10 for thermal cook-off. The original HMX model and analysis scheme were developed by Yoh et.al. for use in the ALE3D modeling framework. The current results were built to remedy the deficiencies of that original model. We concentrated our efforts in four areas. The first area was addition of porosity to the chemical material model framework in ALE3D that is used to model the HMX explosive formulation. This is needed to handle the roughly 2% porosity in solid explosives. The second area was the improvement of the HMX reaction network, which included the inclusion of a reactive phase change model base on work by Henson et.al. The third area required adding early decomposition gas species to the CHEETAH material database to develop more accurate equations of state for gaseous intermediates and products. Finally, it was necessary to improve the implicit mechanics module in ALE3D to more naturally handle the long time scales associated with thermal cook-off. The application of the resulting framework to the analysis of the Scaled Thermal Explosion (STEX) experiments will be discussed.

Fabrication of an SPR Sensor Surface with Antifouling Properties for Highly Sensitive Detection of 2,4,6-Trinitrotoluene Using Surface-Initiated Atom Transfer Polymerization

Directory of Open Access Journals (Sweden)

Kiyoshi Toko

2013-07-01

Full Text Available In this study, we modified a surface plasmon resonance immunosensor chip with a polymer using surface-initiated atom transfer polymerization (SI-ATRP for the highly sensitive detection of 2,4,6-trinitrotoluene (TNT. To immobilize a TNT analogue on the polymer, mono-2-(methacryloyloxyethylsuccinate (MES, which has a carboxyl group, was used in this study. However, the anti-TNT antibody may adsorb non-specifically on the polymer surface by an electrostatic interaction because MES is negatively charged. Therefore, a mixed monomer with MES and diethylaminoethylmethacrylate (DEAEM, which has a tertiary amino group and is positively charged, was prepared to obtain electroneutrality for suppressing the nonspecific adsorption. The detection of TNT was performed by inhibition assay using the polymer surface. To ensure high sensitivity to TNT, the affinity between the surface and the antibody was optimized by controlling the density of the initiator for ATRP by mixing two types of self-assembled monolayer reagents. As a result, a limit of detection of 5.7 pg/mL (ppt for TNT was achieved using the optimized surface.

Exposure to trinitrotoluene and health effects among workers in an artillery and ammunition plant.

Science.gov (United States)

Kongtip, Pornpimol; Preklang, Smart; Yoosook, Witaya; Chantanakul, Suttinun

2012-06-01

To determine urinary trinitrotoluene (TNT), 2-amino-4, 6-dinitrotoluene (2ADNT) and 4-amino-2, 6-dinitrotoluene (4ADNT) and health effects upon workers in an ammunition plant. The urine samples from forty munition workers and forty office workers were monitored for TNT and its metabolites by gas chromatography-mass spectrometry. The workers were interviewed with a questionnaire. The median levels of TNT and its metabolites were 112.84 and ranged from non-detectable (ND) to 1,833.81 mg/L. Median levels for 2ADNT were 11.66, ranging from ND to 360.89 mg/L. Median levels for 4ADNT were 19.95 and ranged from ND to 314.28 mg/L. There were significant correlations between TNT and 2ADNT in urine (r = 0. 700, p-value workers reported eye, nose and throat irritations, weakness and headaches with considerably higher frequency than non-exposed workers. TNT levels in urine were strongly associated with 4ADNT and 2ADNT levels. Workers exposed to TNT complained of nose, throat and eye irritation, along with overall weakness and headaches.

Self-Remediating Energetic Fills Based on Cyclic Dinitroureas

Science.gov (United States)

2016-12-01

al., 2006). The Environmental Protection Agency (EPA) has issued a drinking water guideline limit ( lifetime ) for RDX of 2 µg/L. RDX has high to...The lid was inverted , placed above the sample, and crimped into place using a hermetic press. The samples were heated from 25 °C to 300 °C at a

Groundwater Chemistry and Microbial Ecology Effects on Explosives Biodegradation

Science.gov (United States)

2008-09-01

hexahydro-1,3,5-trinitro-1,3,5-triazine catalyzed by a 17 NAD(P)H: nitrate oxidoreductase from Aspergillus niger. Environ Sci Technol 18 36:3104-3108. 19...Azospirillum sp. B518 [AB049112] RDX clone 8 [EU907872] RDX clone 2 [EU907866] Azospirillum sp. 2436 [EF422176] Pleomorphomonas oryzae F-4

Explosive Contamination from Substrate Surfaces: Differences and Similarities in Contamination Techniques Using RDX and C-4

Science.gov (United States)

Miller, C. J.; Yoder, T. S.

2010-06-01

Explosive trace detection equipment has been deployed to airports for more than a decade. During this time, the need for standardized procedures and calibrated trace amounts for ensuring that the systems are operating properly and detecting the correct explosive has been apparent but a standard representative of a fingerprint has been elusive. Standards are also necessary to evaluate instrumentation in the laboratories during development and prior to deployment to determine sample throughput, probability of detection, false positive/negative rates, ease of use by operator, mechanical and/or software problems that may be encountered, and other pertinent parameters that would result in the equipment being unusable during field operations. Since many laboratories do not have access to nor are allowed to handle explosives, the equipment is tested using techniques aimed at simulating the actual explosives fingerprint. This laboratory study focused on examining the similarities and differences in three different surface contamination techniques that are used to performance test explosive trace detection equipment in an attempt to determine how effective the techniques are at replicating actual field samples and to offer scenarios where each contamination technique is applicable. The three techniques used were dry transfer deposition of standard solutions using the Transportation Security Laboratory’s (TSL) patented dry transfer techniques (US patent 6470730), direct deposition of explosive standards onto substrates, and fingerprinting of actual explosives onto substrates. RDX was deposited on the surface of one of five substrates using one of the three different deposition techniques. The process was repeated for each substrate type using each contamination technique. The substrate types used were: 50% cotton/50% polyester as found in T-shirts, 100% cotton with a smooth surface such as that found in a cotton dress shirt, 100% cotton on a rough surface such as that

Integrated Data Collection Analysis (IDCA) Program — Ammonium Nitrate

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorensen, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Phillips, Jason J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Shelley, Timothy J. [Bureau of Alcohol, Tobacco and Firearms, Redstone Arsenal, AL (United States); Reyes, Jose A. [Applied Research Associates, Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2013-05-17

The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small- Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of ammonium nitrate (AN). AN was tested, in most cases, as both received from manufacturer and dried/sieved. The participants found the AN to be: 1) insensitive in Type 12A impact testing (although with a wide range of values), 2) completely insensitive in BAM friction testing, 3) less sensitive than the RDX standard in ABL friction testing, 4) less sensitive than RDX in ABL ESD testing, and 5) less sensitive than RDX and PETN in DSC thermal analyses.

The influence of surface roughness and high pressure torsion on the growth of anodic titania nanotubes on pure titanium

Energy Technology Data Exchange (ETDEWEB)

Hu, Nan; Gao, Nong, E-mail: N.Gao@soton.ac.uk; Starink, Marco J.

2016-11-30

Highlights: • HPT has substantially improved the UTS and Hv of pure Ti. • TNT layers was fabricated on UFG Ti made by HPT. • Influence of sample preparation on TNT layers was systematically studied. • Oxide dissolution was accelerated when TNTs formed on the HPT sample. - Abstract: Anodic titanium dioxide nanotube (TNT) arrays have wide applications in photocatalytic, catalysis, electronics, solar cells and biomedical implants. When TNT coatings are combined with severe plastic deformation (SPD), metal processing techniques which efficiently improve the strength of metals, a new generation of biomedical implant is made possible with both improved bulk and surface properties. This work investigated the effect of processing by high pressure torsion (HPT) and different mechanical preparations on the substrate and subsequently on the morphology of TNT layers. HPT processing was applied to refine the grain size of commercially pure titanium samples and substantially improved their strength and hardness. Subsequent anodization at 30 V in 0.25 wt.% NH{sub 4}F for 2 h to form TNT layers on sample surfaces prepared with different mechanical preparation methods was carried out. It appeared that the local roughness of the titanium surface on a microscopic level affected the TNT morphology more than the macroscopic surface roughness. For HPT-processed sample, the substrate has to be pre-treated by a mechanical preparation finer than 4000 grit for HPT to have a significant influence on TNTs. During the formation of TNT layers the oxide dissolution rate was increased for the ultrafine-grained microstructure formed due to HPT processing.

Adsorption of 2,4,6-trinitrotoluene on carboxylated porous polystyrene microspheres

International Nuclear Information System (INIS)

Ye Zhengfang; Meng Qingqiang; Lu Shengtao

2012-01-01

Large-pore-size (150 nm) polystyrene (PSt) microspheres were carboxylated with phthalic anhydride (PA) through Friedel-Crafts acetylation to study the adsorption of 2,4,6-trinitrotoluene (TNT) on this material from aqueous solution. The scanning electron microscope (SEM) images and mercury porosimetry measurements (MPM) of the microspheres showed that the pore structure was unchanged during the reaction. High adsorption capacity (11.2 mg g -1 of suction-dried adsorbent) and adsorption rate (33.9 mg g -1 h -1 ) for TNT were observed during the study. As shown by the adsorption isotherm, the adsorption of TNT on PA-PSt can be described by the Freundlich adsorption equation, indicating heterogeneous adsorption process. On-column adsorption of TNT on PA-PSt and elution indicated that TNT can be completely removed from aqueous solution and condensed into acetone.

Recent advances in thermal analysis and stability evaluation of insensitive plastic bonded explosives (PBXs)

International Nuclear Information System (INIS)

Yan, Qi-Long; Zeman, Svatopluk; Elbeih, Ahmed

2012-01-01

Highlights: ► We summarize currently used insensitive polymer based explosives and their ingredients. ► We examine the calculation methods that are suitable for kinetic evaluation of polymer based explosives. ► The calculation method for thermal stability parameters of polymer based explosives are summarized, which mainly include shelf life, explosion delay, critical temperature, thermostability threshold, 500 day cookoff temperature and approximate time to explosion. ► The polymer bases could greatly affect the thermal properties of PBXs, including their thermal stability, kinetic parameters and thermodynamic properties. ► PBXs, containing some innovative energetic fillers such as CL-20, NTO, Fox-12 and BCHMX, are only at design stage, which need more research work in the future. - Abstract: In this paper, several fundamental investigations published over the past decades with regard to the thermal analysis of polymer-based explosives (PBXs) have been briefly reviewed. A number of explosive fillers and polymer bases that were used as their main ingredients of PBXs are summarized herein. In addition, the calculation methods for their decomposition kinetics and thermal stability parameters are also introduced in detail. It was concluded that only PBXs based on HMX, RDX and TATB have been widely investigated, and that some other PBXs containing innovative fillers, such as CL-20, TNAZ, NTO and BCHMX are at the design stage. The isoconversional methods and model fitting procedures are usually used to analyze the discrete thermolysis processes of PBXs. In addition, their thermal stability parameters such as shelf life, explosion delay, critical temperature, thermostability threshold, 500-day cookoff temperature and approximate time to explosion could be calculated easily from the kinetic data.

Solid-solid phase transformation via internal stress-induced virtual melting, significantly below the melting temperature. Application to HMX energetic crystal.

Science.gov (United States)

Levitas, Valery I; Henson, Bryan F; Smilowitz, Laura B; Asay, Blaine W

2006-05-25

We theoretically predict a new phenomenon, namely, that a solid-solid phase transformation (PT) with a large transformation strain can occur via internal stress-induced virtual melting along the interface at temperatures significantly (more than 100 K) below the melting temperature. We show that the energy of elastic stresses, induced by transformation strain, increases the driving force for melting and reduces the melting temperature. Immediately after melting, stresses relax and the unstable melt solidifies. Fast solidification in a thin layer leads to nanoscale cracking which does not affect the thermodynamics or kinetics of the solid-solid transformation. Thus, virtual melting represents a new mechanism of solid-solid PT, stress relaxation, and loss of coherence at a moving solid-solid interface. It also removes the athermal interface friction and deletes the thermomechanical memory of preceding cycles of the direct-reverse transformation. It is also found that nonhydrostatic compressive internal stresses promote melting in contrast to hydrostatic pressure. Sixteen theoretical predictions are in qualitative and quantitative agreement with experiments conducted on the PTs in the energetic crystal HMX. In particular, (a) the energy of internal stresses is sufficient to reduce the melting temperature from 551 to 430 K for the delta phase during the beta --> delta PT and from 520 to 400 K for the beta phase during the delta --> beta PT; (b) predicted activation energies for direct and reverse PTs coincide with corresponding melting energies of the beta and delta phases and with the experimental values; (c) the temperature dependence of the rate constant is determined by the heat of fusion, for both direct and reverse PTs; results b and c are obtained both for overall kinetics and for interface propagation; (d) considerable nanocracking, homogeneously distributed in the transformed material, accompanies the PT, as predicted by theory; (e) the nanocracking does not

Development of a short-term (<12 days), plant-based screening method to assess the bioavailability, bioconcentration, and phytotoxicity of Hexahydro-1,3,5- Trinitro-1,3,5-Tiazine (RDZ) to terrestrial plants

Science.gov (United States)

Linda Winfield; Steven D' Surney; John Rodgers

2000-01-01

Limited amounts of information have been published on the environmental impacts of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) to terrestrial plant communities. RDX is one of the two high-explosive compounds used by the U.S. military (Davis 1998) and classified as a priority pollutant by the U.S. Environmental Protection Agency (USEPA). Millions of acres of land on...

Changes in Blow-Off Velocity Observed in Two Explosives at the Threshold for Sustained Ignition Using the Modified Gap Test

Science.gov (United States)

Lee, R. J.; Forbes, J. W.; Tasker, D. G.; Orme, R. S.

2009-12-01

The Modified Gap Test was used to quantify different levels of partial reaction for various input stresses. This test configuration has been historically useful in highlighting thresholds for first reaction, sustained ignition, and detonation. Two different HMX based compositions were studied; a cast-cured composition with 87% HMX and a pressed composition with 92% HMX. Each explosive was prepared from large industrially produced batches consisting of different unreactive polymeric binder systems. Short samples (50.8 mm in diameter and 12.7 mm thick) were shock loaded using the standard large-scale gap test donor system. Product-cloud blow-off velocities at the opposite end of the sample were measured using a high-speed digital-camera. Velocity versus input pres sure plots provided changes in reactivity that had developed by the 12.7 mm run distance. Results appear consistent for the lower input stresses. In contrast, the results varied widely in a range of input stresses around the transition to detonation in both explosives. These results indicate that both explosives are subject to large variation in blow-off velocity in a range of input stresses near the threshold for prompt detonation. This is explained by localized variations of HMX particle size and density in industrially prepared samples. Approved for public release, Distribution unlimited, IHDIV Log No. 09-108.

Transformation of trinitrotoluene to triaminotoluene by mixed cultures incubated under methanogenic conditions

Energy Technology Data Exchange (ETDEWEB)

Hwang, P.; Chow, T.; Adrian, N.R.

2000-04-01

2,4,6-Trinitrotoluene (TNT) is an explosive widely used by the military. Although it is no longer manufactured in the US, large amounts of wastewater are generated annually from load, assembly, packing, and demilitarization operations. Granular-activated carbon adsorption is the standard technology for treating wastewater containing TNT and maintaining discharges within the limits established under the National Pollutant Discharge Elimination System. Studies evaluating biological treatment of pink water with an anaerobic fluidized-bed, granular-activated carbon bioreactor have been promising, but the fate of TNT is unknown. The authors investigated the anaerobic transformation of TNT by biofilm microorganisms obtained from a wastewater treatment plant receiving explosive manufacturing wastewater. The TNT was transformed to a mixture of 2-amino-4,6-dinitrotoluene; 4-amino-2,6-dinitrotoluene; 2,4-diamino-6-nitrotoluene; and 2,6-diamino-4-nitrotoluene before culminating in the formation of triaminotoluene (TAT). Triaminotoluene was susceptible to further degradation under anaerobic conditions, but its fate was not determined. Methane formation was inhibited but resumed after the depletion of the diaminonitrotoluene isomers. These studies demonstrate near stoichiometric formation of TAT from TNT and the transformation of 2-amino-4,6-dinitrotoluene to 2,4-diamino-6-nitrotoluene and 2,6-diamino-4-nitrotoluene by a mixed culture incubated under methanogenic conditions. This evidence indicates TAT is also a likely end-product of TNT biodegradation in the anaerobic fluidized fed bioreactor.

Chemical and toxicological characterization of slurry reactor biotreatment of explosives-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Griest, W.H.; Stewart, A.J.; Vass, A.A.; Ho, C.H.

1998-08-01

Treatment of 2,4,6-trinitrotoluene (TNT)-contaminated soil in the Joliet Army Ammunition Plant (JAAP) soil slurry bioreactor (SSBR) eliminated detectable TNT but left trace levels of residual monoamino and diamino metabolites under some reactor operating conditions. The reduction of solvent-extractable bacterial mutagenicity in the TNT-contaminated soil was substantial and was similar to that achieved by static pile composts at the Umatilla Army Depot Activity (UMDA) field demonstration. Aquatic toxicity to Ceriodaphnia dubia from TNT in the leachates of TNT-contaminated soil was eliminated in the leachates of JAAP SSBR product soil. The toxicity of soil product leachates to Ceriodaphnia dubia was reasonably predicted using the specific toxicities of the components detected, weighted by their leachate concentrations. In samples where TNT metabolites were observed in the soil product and its leachates, this method determined that the contribution to predicted toxicity values was dominated by trace amounts of the diamino-metabolites, which are very toxic to ceriodaphnia dubia. When the SSBR operating conditions reduced the concentrations of TNT metabolites in the product soils and their leachates to undetectable concentrations, the main contributors to predicted aquatic toxicity values appeared to be molasses residues, potassium, and bicarbonate. Potassium and bicarbonate are beneficial or benign to the environment, and molasses residues are substantially degraded in the environment. Exotoxins, pathogenic bacteria, inorganic particles, ammonia, and dissolved metals did not appear to be important to soil product toxicity.

Crystal morphology variation in inkjet-printed organic materials

Science.gov (United States)

Ihnen, Andrew C.; Petrock, Anne M.; Chou, Tsengming; Samuels, Phillip J.; Fuchs, Brian E.; Lee, Woo Y.

2011-11-01

The recent commercialization of piezoelectric-based drop-on-demand inkjet printers provides an additive processing platform for producing and micropatterning organic crystal structures. We report an inkjet printing approach where macro- and nano-scale energetic composites composed of cyclotrimethylenetrinitramine (RDX) crystals dispersed in a cellulose acetate butyrate (CAB) matrix are produced by direct phase transformation from organic solvent-based all-liquid inks. The characterization of printed composites illustrates distinct morphological changes dependent on ink deposition parameters. When 10 pL ink droplets rapidly formed a liquid pool, a coffee ring structure containing dendritic RDX crystals was produced. By increasing the substrate temperature, and consequently the evaporation rate of the pooled ink, the coffee ring structure was mitigated and shorter dendrites from up to ∼1 to 0.2 mm with closer arm spacing from ∼15 to 1 μm were produced. When the nucleation and growth of RDX and CAB were confined within the evaporating droplets, a granular structure containing nanoscale RDX crystals was produced. The results suggest that evaporation rate and microfluidic droplet confinement can effectively be used to tailor the morphology of inkjet-printed energetic composites.

Burning characteristics of microcellular combustible objects

Directory of Open Access Journals (Sweden)

Wei-tao Yang

2014-06-01

Full Text Available Microcellular combustible objects for application of combustible case, caseless ammunition or combustible detonator-holding tubes are fabricated through one-step foaming process, in which supercritical CO2 is used as foaming agent. The formulations consist of inert polymer binder and ultra fine RDX. For the inner porous structures of microcellular combustible objects, the cell sizes present a unimodal or bimodal distribution by adjusting the foaming conditions. Closed bomb test is to investigate the influence of both porous structure style and RDX content on burning behavior. The sample with bimodal distribution of cell sizes burns faster than that with unimodal distribution, and the concentration of RDX can influence the burning characteristics in a positive manner. In addition, the translation of laminar burning to convective burning is determined by burning rate versus pressure curves of samples at two different loading densities, and the resulting transition pressure is 30 MPa. Moreover, the samples with bigger sample size present higher burning rate, resulting in providing deeper convective depth. Dynamic vivacity of samples is also studied. The results show that the vivacity increases with RDX content and varies with inner structure.

Degradation of 2,4,6-trinitrotoluene by P. aeruginosa and characterization of some metabolites

Directory of Open Access Journals (Sweden)

Hatice Aysun Mercimek

2015-03-01

Full Text Available Degradation of 2,4,6-trinitrotoluene (TNT, a nitroaromatic explosive found in the soil and ground water, was investigated using Pseudomonas aeruginosa in in vitroexperiments. Biodegradable abilitiy of this bacteria was performed with 50 and 75 mg L−1 TNT concentrations in a defined liquid medium for 96 h time period. Treatment of TNT in supernatant samples taken at 0, 6, 12, 24, 48, 72 and 96 h from agitated vessels was followed by reverse-phase high-performance liquid chromatography (HPLC. In cultures supplemented with 50 and 75 mgL−1 TNT, after 96 h of incubation 46% and 59% reduction were detected respectively. Two metabolites as degradation intermediates with nitrite release into the medium, 2,4-dinitrotoluene (2,4-DNT and 4-aminodinitrotoluene (4-ADNT, were elucidated by thin layer chromatography (TLC and gas chromatography-mass spectrometry (GC-MS. These findings clearly indicate that Pseudomonas aeruginosa can be used in bioremediation of TNT contaminated sites.

Frequency and significance of troponin T elevation in acute ischemic stroke

DEFF Research Database (Denmark)

Jensen, Jesper K.; Kristensen, Søren R.; Bak, Søren

2007-01-01

Elevated levels of troponin have been reported in patients with acute ischemic stroke. In this prospective study, the prevalence and characteristics of troponin elevation were examined in 244 patients with acute ischemic stroke but without overt ischemic heart disease. Troponin T (TnT) and creatine...... for a mean of 19 +/- 7 months, with all-cause mortality as the clinical end point. Elevated levels of TnT (>0.03 micro g/L) and creatine kinase-MB (> or =10 micro g/L) were observed in 10% and 9% of patients, respectively. Patients with elevated TnT had higher frequencies of heart and/or renal failure....... Perfusion abnormalities on myocardial perfusion scintigraphy at rest were not more frequent or pronounced in patients with TnT levels of > or =0.10 micro g/L than in the control group. Only 7 patients (3%) had elevations of TnT or creatine kinase-MB and electrocardiographic changes suggesting acute...

Species-specific differences in peroxisome proliferation, catalase, and SOD2 upregulation as well as toxicity in human, mouse, and rat hepatoma cells induced by the explosive and environmental pollutant 2,4,6-trinitrotoluene.

Science.gov (United States)

Naumenko, Ekaterina Anatolevna; Ahlemeyer, Barbara; Baumgart-Vogt, Eveline

2017-03-01

2,4,6-Trinitrotoluene (TNT) has been widely used as an explosive substance and its toxicity is still of interest as it persisted in polluted areas. TNT is metabolized in hepatocytes which are prone to its toxicity. Since analysis of the human liver or hepatocytes is restricted due to ethical reasons, we investigated the effects of TNT on cell viability, reactive oxygen species (ROS) production, peroxisome proliferation, and antioxidative enzymes in human (HepG2), mouse (Hepa 1-6), and rat (H4IIEC3) hepatoma cell lines. Under control conditions, hepatoma cells of all three species were highly comparable exhibiting identical proliferation rates and distribution of their cell cycle phases. However, we found strong differences in TNT toxicity with the lowest IC 50 values (highest cell death rate) for rat cells, whereas human and mouse cells were three to sevenfold less sensitive. Moreover, a strong decrease in cellular dehydrogenase activity (MTT assay) and increased ROS levels were noted. TNT caused peroxisome proliferation with rat hepatoma cells being most responsive followed by those from mouse and human. Under control conditions, rat cells contained fivefold higher peroxisomal catalase and mitochondrial SOD2 activities and a twofold higher capacity to reduce MTT than human and mouse cells. TNT treatment caused an increase in catalase and SOD2 mRNA and protein levels in human and mouse, but not in rat cells. Similarly, human and mouse cells upregulated SOD2 activity, whereas rat cells failed therein. We conclude that TNT induced oxidative stress, peroxisome proliferation and mitochondrial damage which are highest in rat cells rendering them most susceptible toward TNT. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 989-1006, 2017. © 2016 Wiley Periodicals, Inc.

Serial High-Sensitivity Troponin T in Post-Primary Angioplasty Exercise Test

Directory of Open Access Journals (Sweden)

Humberto Andres Vaz

2016-04-01

Full Text Available Abstract Background: The kinetics of high-sensitivity troponin T (hscTnT release should be studied in different situations, including functional tests with transient ischemic abnormalities. Objective: To evaluate the release of hscTnT by serial measurements after exercise testing (ET, and to correlate hscTnT elevations with abnormalities suggestive of ischemia. Methods: Patients with acute ST-segment elevation myocardial infarction (STEMI undergoing primary angioplasty were referred for ET 3 months after infarction. Blood samples were collected to measure basal hscTnT immediately before (TnT0h, 2 (TnT2h, 5 (TnT5h, and 8 hours (TnT8h after ET. The outcomes were peak hscTnT, TnT5h/TnT0h ratio, and the area under the blood concentration-time curve (AUC for hscTnT levels. Log-transformation was performed on hscTnT values, and comparisons were assessed with the geometric mean ratio, along with their 95% confidence intervals. Statistical significance was assessed by analysis of covariance with no adjustment, and then, adjusted for TnT0h, age and sex, followed by additional variables (metabolic equivalents, maximum heart rate achieved, anterior wall STEMI, and creatinine clearance. Results: This study included 95 patients. The highest geometric means were observed at 5 hours (TnT5h. After adjustments, peak hscTnT, TnT5h/TnT0h and AUC were 59% (p = 0.002, 59% (p = 0.003 and 45% (p = 0.003 higher, respectively, in patients with an abnormal ET as compared to those with normal tests. Conclusion: Higher elevations of hscTnT may occur after an abnormal ET as compared to a normal ET in patients with STEMI.

Role of additives in combustion waves and effect on stable combustion limit of double-base propellants

Energy Technology Data Exchange (ETDEWEB)

Kubota, N [Japan Defence Agency, Tachikawa. 3. Research Center

1978-12-01

The effect of additives on the flame structures and the burning rates of double-base propellants have been examined by means of photographic observations and temperature profile measurements. The additives used for this study are lead salicylate (PbSa, 2%), nickel (Ni, 1%), ammonium perchlorate (AP, 30%), and cyclotetramethylene tetranitramine (HMX, 30%). The addition of PbSa increases the burning rate, but does not improve the flame temperature characteristics. The addition of Ni increases the flame temperature significantly at pressures below 30 atm. The Ni acts as a catalyst to promote the flame reaction while it does not act as a burning rate modifier. The additions of AP and HMX increase the thermal performance of the propellant system, however, the HMX does not improve the stable combustion limit of the rocket motor at low pressures. The addition of Ni or AP is found to increase the flame temperature at pressures below 30 atm, and the stable combustion limits is lowered to below 3 atm.

Kinetic energy budgets near the turbulent/nonturbulent interface in jets

Science.gov (United States)

Taveira, Rodrigo R.; da Silva, Carlos B.

2013-01-01

The dynamics of the kinetic energy near the turbulent/nonturbulent (T/NT) interface separating the turbulent from the irrotational flow regions is analysed using three direct numerical simulations of turbulent planar jets, with Reynolds numbers based on the Taylor micro-scale across the jet shear layer in the range Reλ ≈ 120-160. Important levels of kinetic energy are already present in the irrotational region near the T/NT interface. The mean pressure and kinetic energy are well described by the Bernoulli equation in this region and agree with recent results obtained from rapid distortion theory in the turbulent region [M. A. C. Teixeira and C. B. da Silva, "Turbulence dynamics near a turbulent/non-turbulent interface," J. Fluid Mech. 695, 257-287 (2012)], 10.1017/jfm.2012.17 while the normal Reynolds stresses agree with the theoretical predictions from Phillips ["The irrotational motion outside a free turbulent boundary," Proc. Cambridge Philos. Soc. 51, 220 (1955)], 10.1017/S0305004100030073. The use of conditional statistics in relation to the distance from the T/NT interface allow a detailed study of the build up of kinetic energy across the T/NT interface, pointing to a very different picture than using classical statistics. Conditional kinetic energy budgets show that apart from the viscous dissipation of kinetic energy, the maximum of all the mechanisms governing the kinetic energy are concentrated in a very narrow region distancing about one to two Taylor micro-scales from the T/NT interface. The (total and fluctuating) kinetic energy starts increasing in the irrotational region by pressure-velocity interactions - a mechanism that can act at distance, and continue to grow by advection (for the total kinetic energy) and turbulent diffusion (for the turbulent kinetic energy) inside the turbulent region. These mechanisms tend to occur preferentially around the core of the large-scale vortices existing near T/NT interface. The production of turbulent

Data Summary for Trinitrotoluene

Science.gov (United States)

1986-09-01

carious and noncarious tooth injury and periodontal and oral cavity mucous membrane disease ; cataract formation; and biochemical changes, e.g...causes of death to TNT- exposed animals. Cats, dogs , and humans appear to be more sensitive to TNT than are rabbits and rats. LD50s reported for male...rabbits, and dogs show that TNT distributes throughout the body to include the blood, liver, kidneys, lungs, spleen, brain, fat, muscle, and GI tract

Halogenated Explosives to Defeat Biological Agents

Science.gov (United States)

2015-09-01

for example. However, in testing this nitrating reagent, it was decided to use a purer and less valuable substrate as a model reactant: the...secondary nitramine but possibly containing both N-nitro derivatives. Figure 9. “Nonacidic” nitration of a model reactant, 2-(trifluoromethyl... economics of possible alternative technical approaches that might produce it—led to its abandonment, in this project, in favor of TFM-RDX. TFM-RDX was a

Application of a Homogenous Assay for the Detection of 2,4,6-Trinitrotoluene to Environmental Water Samples

Directory of Open Access Journals (Sweden)

Ellen R. Goldman

2005-01-01

Full Text Available A homogeneous assay was used to detect 2,4,6-trinitrotoluene (TNT spiked into environmental water samples. This assay is based on changes in fluorescence emission intensity when TNT competitively displaces a fluorescently labeled, TNT analog bound to an anti-TNT antibody. The effectiveness of the assay was highly dependent on the source of the sample being tested. As no correlation between pH and assay performance was observed, ionic strength was assumed to be the reason for variation in assay results. Addition of 10x phosphate-buffered saline to samples to increase their ionic strength to that of our standard laboratory buffer (about 0.17 M significantly improved the range over which the assay functioned in several river water samples.

Analysis of microstructure-dependent shock dissipation and hot-spot formation in granular metalized explosive

Science.gov (United States)

Chakravarthy, Sunada; Gonthier, Keith A.

2016-07-01

Variations in the microstructure of granular explosives (i.e., particle packing density, size, shape, and composition) can affect their shock sensitivity by altering thermomechanical fields at the particle-scale during pore collapse within shocks. If the deformation rate is fast, hot-spots can form, ignite, and interact, resulting in burn at the macro-scale. In this study, a two-dimensional finite and discrete element technique is used to simulate and examine shock-induced dissipation and hot-spot formation within low density explosives (68%-84% theoretical maximum density (TMD)) consisting of large ensembles of HMX (C4H8N8O8) and aluminum (Al) particles (size ˜ 60 -360 μm). Emphasis is placed on identifying how the inclusion of Al influences effective shock dissipation and hot-spot fields relative to equivalent ensembles of neat/pure HMX for shocks that are sufficiently strong to eliminate porosity. Spatially distributed hot-spot fields are characterized by their number density and area fraction enabling their dynamics to be described in terms of nucleation, growth, and agglomeration-dominated phases with increasing shock strength. For fixed shock particle speed, predictions indicate that decreasing packing density enhances shock dissipation and hot-spot formation, and that the inclusion of Al increases dissipation relative to neat HMX by pressure enhanced compaction resulting in fewer but larger HMX hot-spots. Ensembles having bimodal particle sizes are shown to significantly affect hot-spot dynamics by altering the spatial distribution of hot-spots behind shocks.

Effects of void anisotropy on the ignition and growth rates of energetic materials

Science.gov (United States)

Rai, Nirmal Kumar; Sen, Oishik; Udaykumar, H. S.

2017-06-01

Initiation of heterogeneous energetic materials is thought to occur at hot spots; reaction fronts propagate from sites of such hot spots into the surrounding material resulting in complete consumption of the material. Heterogeneous materials, such as plastic bonded explosives (PBXs) and pressed materials contain numerous voids, defects and interfaces at which hot spots can occur. Amongst the various mechanisms of hot spot formation, void collapse is considered to be the predominant one in the high strain rate loading conditions. It is established in the past the shape of the voids has a significant effect on the initiation behavior of energetic materials. In particular, void aspect ratio and orientations play an important role in this regard. This work aims to quantify the effects of void aspect ratio and orientation on the ignition and growth rates of chemical reaction from the hot spot. A wide range of aspect ratio and orientations is considered to establish a correlation between the ignition and growth rates and the void morphology. The ignition and growth rates are obtained from high fidelity reactive meso-scale simulations. The energetic material considered in this work is HMX and Tarver McGuire HMX decomposition model is considered to capture the reaction mechanism of HMX. The meso-scale simulations are performed using a Cartesian grid based Eulerian solver SCIMITAR3D. The void morphology is shown to have a significant effect on the ignition and growth rates of HMX.

Investigation of a new passive sampler for the detection of munitions compounds in marine and freshwater systems.

Science.gov (United States)

Warren, Joseph K; Vlahos, Penny; Smith, Richard; Tobias, Craig

2018-07-01

Over the last century, unexploded ordnances have been disposed of in marine shelf systems because of a lack of cost-effective alternatives. Underwater unexploded ordnances have the potential to leak 2,4,6-trinitrotoluene (TNT) and 1,3,5-trinitro-1,3,5-triazine (RDX), commonly used chemical munitions, and contaminate local waters, biota, and sediments. The rate at which this contamination occurs in the environment is relatively unknown, and the cost- and time-prohibitive nature of sampling across sites makes mapping difficult. In the present study we assessed the efficacy of ethylene-vinyl acetate (EVA) for sampling relatively soluble munitions compounds over a range of environmental conditions (i.e., changes in temperature and salinity) and optimized the composition of the passive sampling polymer. The EVA sampler was able to successfully detect ambient concentrations of lingering munitions compounds from field sites containing unexploded ordnances. The sampler affinity for the munitions in terms of an EVA-water partition coefficient was greater than the standard octanol water values for each target compound. Partitioning of compounds onto EVA over the natural ranges of salinity did not change significantly, although uptake varied consistently and predictably with temperature. Increasing the vinyl acetate to ethylene ratio of the polymer corresponded to an increase in uptake capacity, consistent with enhanced dipole-dipole interactions between the munitions and the polymer. This sampler provides a cost-effective means to map and track leakage of unexploded ordnances both spatially and temporally. Environ Toxicol Chem 2018;37:1990-1997. © 2018 SETAC. © 2018 SETAC.

Nanomolecular gas sensor architectures based on functionalized carbon nanotubes for vapor detection

Science.gov (United States)

Hines, Deon; Zhang, Henan; Rümmeli, Mark H.; Adebimpe, David; Akins, Daniel L.

2015-05-01

There is enormous interest in detection of simple & complex odors by mean of electronic instrumentation. Specifically, our work focuses on creating derivatized-nanotube-based "electronic noses" for the detection and identification of gases, and other materials. We have grafted single-walled carbon nanotubes (SWNTs) with an array of electron-donating and electron withdrawing moieties and have characterized some of the physicochemical properties of the modified nanotubes. Gas sensing elements have been fabricated by spin coating the functionalized nanotubes onto interdigitated electrodes (IDE's), creating an array of sensors. Each element in the sensor array can contain a different functionalized matrix. This facilitates the construction of chemical sensor arrays with high selectivity and sensitivity; a methodology that mimics the mammalian olfactory system. Exposure of these coated IDEs to organic vapors and the successful classification of the data obtained under DC monitoring, indicate that the system can function as gas sensors of high repeatability and selectivity for a wide range of common analytes. Since the detection of explosive materials is also of concern in this research, our next phase focuses on explosives such as, TNT, RDX, and Triacetone Triperoxide (TATP). Sensor data from individual detection are assessed on their own individual merits, after which they are amalgamated and reclassified to present each vapor as unique data point on a 2-dimensional map and with minimum loss of information. This approach can assist the nation's need for a technology to defeat IEDs through the use of methods that detect unique chemical signatures associated with explosive molecules and byproducts.

Using stable isotopes of carbon and nitrogen as in-situ tracers for monitoring the natural attenuation of explosives

National Research Council Canada - National Science Library

Miyares, Paul H

1999-01-01

The use of carbon and nitrogen stable isotope measurements from TNT was examined as a possible tool for monitoring the natural attenuation of TNT incubation studies of spiked soil samples were conducted...

Synthesis and properties of Co-doped titanate nanotubes and their optical sensitization with methylene blue

International Nuclear Information System (INIS)

Ferreira, V.C.; Nunes, M.R.; Silvestre, A.J.; Monteiro, O.C.

2013-01-01

Here we report on a novel chemical route to synthesize homogenous cobalt-doped titanate nanotubes (CoTNT), using an amorphous Co-doped precursor. The influence of the synthesis temperature, autoclave dwell time and metal doping on the structural and microstructural as well as on the optical properties of the synthesized titanate nanotubes is studied and discussed. The optical band gaps of the CoTNT samples are red shifted in comparison with the values determined for the undoped samples, such red shifts bringing the absorption edge of the CoTNT samples into the visible region. CoTNT materials also demonstrate particular high adsorption ability for methylene blue, the amount of the adsorbed dye being higher than the one predictable for a monolayer formation. This suggests the possibility of intercalation of the dye molecule between the TiO 6 layers of the TNT structure. It is also shown that the methylene blue sensitized Co-doped nanostructures are highly stable under UV radiation and present a strong and broad absorption in the visible region. - Highlights: • New hydrothermal chemical route to synthesize cobalt-doped titanate nanotubes. • The Co-doping stabilizes the TNTs morphology in a temperature range of 160–200 °C. • Optical band gaps of CoTNTs are red shifted compared to the TNT samples. • Methylene blue sensitized CoTNTs are highly stable under UV–vis irradiation

Synthesis and properties of Co-doped titanate nanotubes and their optical sensitization with methylene blue

Energy Technology Data Exchange (ETDEWEB)

Ferreira, V.C. [University of Lisbon, Faculty of Sciences, Department of Chemistry and Biochemistry and CQB, Campo Grande, 1749-016 Lisboa (Portugal); Nunes, M.R. [University of Lisbon, Faculty of Sciences, Department of Chemistry and Biochemistry and CCMM, Campo Grande, 1749-016 Lisboa (Portugal); Silvestre, A.J. [Instituto Superior de Engenharia de Lisboa, Department of Physics and ICEMS, R. Conselheiro Emídio Navarro 1, 1959-007 Lisboa (Portugal); Monteiro, O.C., E-mail: ocmonteiro@fc.ul.pt [University of Lisbon, Faculty of Sciences, Department of Chemistry and Biochemistry and CQB, Campo Grande, 1749-016 Lisboa (Portugal)

2013-10-01

Here we report on a novel chemical route to synthesize homogenous cobalt-doped titanate nanotubes (CoTNT), using an amorphous Co-doped precursor. The influence of the synthesis temperature, autoclave dwell time and metal doping on the structural and microstructural as well as on the optical properties of the synthesized titanate nanotubes is studied and discussed. The optical band gaps of the CoTNT samples are red shifted in comparison with the values determined for the undoped samples, such red shifts bringing the absorption edge of the CoTNT samples into the visible region. CoTNT materials also demonstrate particular high adsorption ability for methylene blue, the amount of the adsorbed dye being higher than the one predictable for a monolayer formation. This suggests the possibility of intercalation of the dye molecule between the TiO{sub 6} layers of the TNT structure. It is also shown that the methylene blue sensitized Co-doped nanostructures are highly stable under UV radiation and present a strong and broad absorption in the visible region. - Highlights: • New hydrothermal chemical route to synthesize cobalt-doped titanate nanotubes. • The Co-doping stabilizes the TNTs morphology in a temperature range of 160–200 °C. • Optical band gaps of CoTNTs are red shifted compared to the TNT samples. • Methylene blue sensitized CoTNTs are highly stable under UV–vis irradiation.

The structure and the photocatalytic activity of titania based nanotube and nanofiber coatings

Energy Technology Data Exchange (ETDEWEB)

Radtke, A., E-mail: aradtke@umk.pl [Faculty of Chemistry, Nicolaus Copernicus University, ul. Gagarina 7, 87-100 Toruń (Poland); Piszczek, P.; Topolski, A.; Lewandowska, Ż. [Faculty of Chemistry, Nicolaus Copernicus University, ul. Gagarina 7, 87-100 Toruń (Poland); Talik, E. [A. Chełkowski Institute of Physics, University of Silesia, ul. Uniwersytecka 4, 40-007 Katowice (Poland); Andersen, I. Hald; Nielsen, L. Pleth [Tribology Centre, Danish Technological Institute, Kongsvang Allé 29, 8000 Aarhus C (Denmark); Heikkilä, M.; Leskelä, M. [Centre of Excellence, Laboratory of Inorganic Chemistry, Chemistry Department, Faculty of Science, University of Helsinki, A.I. Virtasen aukio 1, FI-00014 (Finland)

2016-04-15

Graphical abstract: - Highlights: • The photoactivity of TNT and TNF has been quantified by two different methods. • The influence of the TNT and TNF structure on their photoactivity was studied. • The photoactivity comparison of TNT and TNF was carried out. • TNF coatings show higher photoactivity in comparison to TNT. - Abstract: The photocatalytic activity of TiO{sub 2} based nanotube (TNT) and nanofiber (TNF) coatings has been investigated, in correlation to their structure, morphology, specific surface area, acidity and the amount of surface H{sub 2}O molecules and −OH groups. Characterization of these materials was carried out using grazing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, and diffuse reflectance infrared Fourier transform spectroscopy (DRIFT). The photocatalytic activity has been quantified by two different methods, based on the photodegradation of methylene blue (the pattern of water-soluble organic pollutant) and acetone (the pattern of volatile organic pollutant), respectively. Results of our investigations revealed that TNF coatings were significantly more active in case of both photodegradation processes in air and water, as compared to TNT, even if the specific surface area of TNF films was smaller than the adequate surface area of TNT. The microstructure of produced materials, the amount of adsorbed −OH groups and H{sub 2}O molecules located on the surface of materials, and the acidity of the surface, were the main factors which affect their photoactivity. Photocatalytic properties of tubular and porous TiO{sub 2}-based materials are the resultant of the compilation of individual factors impact and any of them cannot be neglected.

The structure and the photocatalytic activity of titania based nanotube and nanofiber coatings

International Nuclear Information System (INIS)

Radtke, A.; Piszczek, P.; Topolski, A.; Lewandowska, Ż.; Talik, E.; Andersen, I. Hald; Nielsen, L. Pleth; Heikkilä, M.; Leskelä, M.

2016-01-01

Graphical abstract: - Highlights: • The photoactivity of TNT and TNF has been quantified by two different methods. • The influence of the TNT and TNF structure on their photoactivity was studied. • The photoactivity comparison of TNT and TNF was carried out. • TNF coatings show higher photoactivity in comparison to TNT. - Abstract: The photocatalytic activity of TiO_2 based nanotube (TNT) and nanofiber (TNF) coatings has been investigated, in correlation to their structure, morphology, specific surface area, acidity and the amount of surface H_2O molecules and −OH groups. Characterization of these materials was carried out using grazing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, and diffuse reflectance infrared Fourier transform spectroscopy (DRIFT). The photocatalytic activity has been quantified by two different methods, based on the photodegradation of methylene blue (the pattern of water-soluble organic pollutant) and acetone (the pattern of volatile organic pollutant), respectively. Results of our investigations revealed that TNF coatings were significantly more active in case of both photodegradation processes in air and water, as compared to TNT, even if the specific surface area of TNF films was smaller than the adequate surface area of TNT. The microstructure of produced materials, the amount of adsorbed −OH groups and H_2O molecules located on the surface of materials, and the acidity of the surface, were the main factors which affect their photoactivity. Photocatalytic properties of tubular and porous TiO_2-based materials are the resultant of the compilation of individual factors impact and any of them cannot be neglected.

Conservation of gene linkage in dispersed vertebrate NK homeobox clusters.

Science.gov (United States)

Wotton, Karl R; Weierud, Frida K; Juárez-Morales, José L; Alvares, Lúcia E; Dietrich, Susanne; Lewis, Katharine E

2009-10-01

Nk homeobox genes are important regulators of many different developmental processes including muscle, heart, central nervous system and sensory organ development. They are thought to have arisen as part of the ANTP megacluster, which also gave rise to Hox and ParaHox genes, and at least some NK genes remain tightly linked in all animals examined so far. The protostome-deuterostome ancestor probably contained a cluster of nine Nk genes: (Msx)-(Nk4/tinman)-(Nk3/bagpipe)-(Lbx/ladybird)-(Tlx/c15)-(Nk7)-(Nk6/hgtx)-(Nk1/slouch)-(Nk5/Hmx). Of these genes, only NKX2.6-NKX3.1, LBX1-TLX1 and LBX2-TLX2 remain tightly linked in humans. However, it is currently unclear whether this is unique to the human genome as we do not know which of these Nk genes are clustered in other vertebrates. This makes it difficult to assess whether the remaining linkages are due to selective pressures or because chance rearrangements have "missed" certain genes. In this paper, we identify all of the paralogs of these ancestrally clustered NK genes in several distinct vertebrates. We demonstrate that tight linkages of Lbx1-Tlx1, Lbx2-Tlx2 and Nkx3.1-Nkx2.6 have been widely maintained in both the ray-finned and lobe-finned fish lineages. Moreover, the recently duplicated Hmx2-Hmx3 genes are also tightly linked. Finally, we show that Lbx1-Tlx1 and Hmx2-Hmx3 are flanked by highly conserved noncoding elements, suggesting that shared regulatory regions may have resulted in evolutionary pressure to maintain these linkages. Consistent with this, these pairs of genes have overlapping expression domains. In contrast, Lbx2-Tlx2 and Nkx3.1-Nkx2.6, which do not seem to be coexpressed, are also not associated with conserved noncoding sequences, suggesting that an alternative mechanism may be responsible for the continued clustering of these genes.

Graphene oxide-based optical biosensor functionalized with peptides for explosive detection.

Science.gov (United States)

Zhang, Qian; Zhang, Diming; Lu, Yanli; Yao, Yao; Li, Shuang; Liu, Qingjun

2015-06-15

A label-free optical biosensor was constructed with biofunctionalized graphene oxide (GO) for specific detection of 2,4,6-trinitrotoluene (TNT). By chemically binding TNT-specific peptides with GO, the biosensor gained unique optoelectronic properties and high biological sensitivity, with transducing bimolecular bonding into optical signals. Through UV absorption detection, increasing absorbance responses could be observed in presence of TNT at different concentrations, as low as 4.40×10(-9) mM, and showed dose-dependence and stable behavior. Specific responses of the biosensor were verified with the corporation of 2,6-dinitrotoluene (DNT), which had similar molecular structure to TNT. Thus, with high sensitivity and selectivity, the biosensor provided a convenient approach for detection of explosives as miniaturizing and integrating devices. Copyright © 2015 Elsevier B.V. All rights reserved.

Enhanced explosive sensing based on bis(methyltetraphenyl)silole nanoaggregate

Science.gov (United States)

Shin, Bomina; Sohn, Honglae

2018-01-01

New photoluminescent bis(methyltetraphenyl)silole nanoaggregates for the detection of trinitrotoluene (TNT) were developed by using aggregation-induced emission property. Bis(methyltetraphenyl)silole nanoaggregates exhibited that photoluminescence (PL) intensity was increased when the water fraction was increased to 90% by volume. Relative PL efficiency of bis(methyltetraphenyl)silole nanoaggregates was exponentially increased to the percent of water fraction and particle diameter was dependent on solvent composition. Particle size of bis(methyltetraphenyl)silole nanoaggregates was tuned by controlling the water fraction by volume. Absolute quantum yield of bis(methyltetraphenyl)silole nanoaggregates in 90% water volume fraction were 32.4%, which increases by about 40 times. Detection of TNT was achieved from the quenching PL measurement of bis(methyltetraphenyl)silole nanoaggregates by adding the TNT. A linear Stern-Volmer relationship was observed for the detection of TNT.

Grenade Range Management Using Lime for Dual Role of Metals Immobilization and Explosives Transformation. Field Demonstration at Fort Jackson, SC

Science.gov (United States)

2008-09-01

and reported the results under the sample delivery groups ( SDG ) L128026 and L128720. The following analytical methods were requested on the chains -of... supplies . The application of hydrated lime to an HGR to provide a mechanism for both metals immobilization and explosives transformation was...Offsites 1 and 2 were supplied by RDX from the control bay, Bay 2. Offsite 3 was supplied by the RDX from lime- treated Bay 4. A period of 6 months had

Integrated Data Collection Analysis (IDCA) Program - NaClO₃/Icing Sugar

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorensen, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Shelley, Timothy J. [Air Force Research Lab. (AFRL), Tyndall Air Force Base, FL (United States); Reyes, Jose A. [Applied Research Associates, Tyndall Air Force Base, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2013-02-11

The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small- Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of a mixture of NaClO₃ and icing sugar—NaClO₃/icing sugar mixture. The mixture was found to: be more sensitive than RDX but less sensitive than PETN in impact testing (180-grit sandpaper); be more sensitive than RDX and about the same sensitivity as PETN in BAM fiction testing; be less sensitive than RDX and PETN except for one participant found the mixture more sensitive than PETN in ABL ESD testing; and to have one to three exothermic features with the lowest temperature event occurring at ~ 160°C always observed in thermal testing. Variations in testing parameters also affected the sensitivity.

An intimately bonded titanate nanotube–polyaniline–gold nanoparticle ternary composite as a scaffold for electrochemical enzyme biosensors

Energy Technology Data Exchange (ETDEWEB)

Liu, Xiaoqiang, E-mail: liuxiaoqiang@henu.edu.cn [Institute of Environmental and Analytical Sciences, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan Province, 475004 (China); Zhu, Jie; Huo, Xiaohe; Yan, Rui [Institute of Environmental and Analytical Sciences, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan Province, 475004 (China); Wong, Danny K.Y., E-mail: Danny.Wong@mq.edu.au [Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW 2109 (Australia)

2016-03-10

In this work, titanate nanotubes (TNTs), polyaniline (PANI) and gold nanoparticles (GNPs) were assembled to form a ternary composite, which was then applied on an electrode as a scaffold of an electrochemical enzyme biosensor. The scaffold was constructed by oxidatively polymerising aniline to produce an emeraldine salt of PANI on TNTs, followed by gold nanoparticle deposition. A novel aspect of this scaffold lies in the use of the emeraldine salt of PANI as a molecular wire between TNTs and GNPs. Using horseradish peroxidase (HRP) as a model enzyme, voltammetric results demonstrated that direct electron transfer of HRP was achieved at both TNT-PANI and TNT-PANI-GNP-modified electrodes. More significantly, the catalytic reduction current of H{sub 2}O{sub 2} by HRP was ∼75% enhanced at the TNT-PANI-GNP-modified electrode, compared to that at the TNT-PANI-modified electrode. The heterogeneous electron transfer rate constant of HRP was found to be ∼3 times larger at the TNT-PANI-GNP-modified electrode than that at the TNT-PANI-modified electrode. Based on chronoamperometric detection of H{sub 2}O{sub 2}, a linear range from 1 to 1200 μM, a sensitivity of 22.7 μA mM{sup −1} and a detection limit of 0.13 μM were obtained at the TNT-PANI-GNP-modified electrode. The performance of the biosensor can be ascribed to the superior synergistic properties of the ternary composite. - Highlights: • A ternary TiO{sub 2} nanotube–polyaniline–gold nanoparticle composite was developed. • New synthetic route for ternary composite with a polyaniline molecular wire between TiO{sub 2} nanotubes and gold nanoparticles. • An electrochemical biosensor with ternary composite as a scaffold. • Ternary composite facilitated improved analytical performance of electrochemical biosensor.

Application of nitrogen-doped TiO{sub 2} nano-tubes in dye-sensitized solar cells

Energy Technology Data Exchange (ETDEWEB)

Tran, Vy Anh; Truong, Trieu Thinh; Phan, Thu Anh Pham; Nguyen, Trang Ngoc [Faculty of Chemistry, University of Science, Vietnam National University, Ho Chi Minh City (Viet Nam); Huynh, Tuan Van [Faculty of Physics and Engineering Physics, University of Science, Vietnam National University, Ho Chi Minh City (Viet Nam); Agresti, Antonio; Pescetelli, Sara [CHOSE (Centre for Hybrid and Organic Solar Energy), Department of Electronic Engineering, University of Rome Tor Vergata (Italy); Le, Tien Khoa [Faculty of Chemistry, University of Science, Vietnam National University, Ho Chi Minh City (Viet Nam); Di Carlo, Aldo [CHOSE (Centre for Hybrid and Organic Solar Energy), Department of Electronic Engineering, University of Rome Tor Vergata (Italy); Lund, Torben [Department of Science and Environment, Roskilde University, DK-4000 (Denmark); Le, So-Nhu [Faculty of Chemistry, University of Science, Vietnam National University, Ho Chi Minh City (Viet Nam); Nguyen, Phuong Tuyet, E-mail: ngtuyetphuong@gmail.com [Faculty of Chemistry, University of Science, Vietnam National University, Ho Chi Minh City (Viet Nam)

2017-03-31

Highlights: • N-doped TiO{sub 2} nanotubes are synthesized by alkaline hydrothermal and reflux method. • Formation of TiO{sub 2} nanotube morphology and anatase phase is shown by TEM, XRD, Raman. • Coordination of NH{sub 4}{sup +} via Ti−O−NH{sub 4}{sup +} or H{sub 4}N{sup +}−Ti−O bonds is indicated by FT-IR and XPS. • Blocking effect of N-doped toward electron transfer on TiO{sub 2} anode is studied by CV. • N-doped TiO{sub 2} improved DSC performance up to 30–40% mainly due to an increase in J{sub sc}. - Abstract: Our research aimed to improve the overall energy conversion efficiency of DSCs by applying nitrogen-doped TiO{sub 2} nano-tubes (N-TNT) for the preparation of DSCs photo-anodes. The none-doped TiO{sub 2} nano-tubes (TNTs) were synthesized by alkaline hydrothermal treatment of Degussa P25 TiO{sub 2} particles in 10 M NaOH. The nano-tubes were N-doped by reflux in various concentrations of NH{sub 4}NO{sub 3}. The effects of nitrogen doping on the structure, morphology, and crystallography of N-TNT were analyzed by transmission electron microscopy (TEM), infrared spectroscopy (IR), Raman spectroscopy, and X-ray photoelectron spectra (XPS). DSCs fabricated with doped N-TNT and TNT was characterized by J-V measurements. Results showed that nitrogen doping significantly enhanced the efficiency of N-TNT cells, reaching the optimum value (η = 7.36%) with 2 M nitrogen dopant, compared to η = 4.75% of TNT cells. The high efficiency of the N-TNT cells was attributed to increased current density due to the reduction of dark current in the DSCs.

Troponin T3 regulates nuclear localization of the calcium channel Ca{sub v}β{sub 1a} subunit in skeletal muscle

Energy Technology Data Exchange (ETDEWEB)

Zhang, Tan; Taylor, Jackson; Jiang, Yang [Department of Internal Medicine-Gerontology, Wake Forest School of Medicine, Winston-Salem, NC 27157 (United States); Pereyra, Andrea S. [Department of Histology, National University of La Plata, 1900 La Plata (Argentina); Messi, Maria Laura; Wang, Zhong-Min [Department of Internal Medicine-Gerontology, Wake Forest School of Medicine, Winston-Salem, NC 27157 (United States); Hereñú, Claudia [Department of Histology, National University of La Plata, 1900 La Plata (Argentina); Delbono, Osvaldo, E-mail: odelbono@wakehealth.edu [Department of Internal Medicine-Gerontology, Wake Forest School of Medicine, Winston-Salem, NC 27157 (United States); Neuroscience Program, Wake Forest School of Medicine, Winston-Salem, NC 27157 (United States)

2015-08-15

The voltage-gated calcium channel (Ca{sub v}) β{sub 1a} subunit (Ca{sub v}β{sub 1a}) plays an important role in excitation–contraction coupling (ECC), a process in the myoplasm that leads to muscle-force generation. Recently, we discovered that the Ca{sub v}β{sub 1a} subunit travels to the nucleus of skeletal muscle cells where it helps to regulate gene transcription. To determine how it travels to the nucleus, we performed a yeast two-hybrid screening of the mouse fast skeletal muscle cDNA library and identified an interaction with troponin T3 (TnT3), which we subsequently confirmed by co-immunoprecipitation and co-localization assays in mouse skeletal muscle in vivo and in cultured C2C12 muscle cells. Interacting domains were mapped to the leucine zipper domain in TnT3 COOH-terminus (160–244 aa) and Ca{sub v}β{sub 1a} NH{sub 2}-terminus (1–99 aa), respectively. The double fluorescence assay in C2C12 cells co-expressing TnT3/DsRed and Ca{sub v}β{sub 1a}/YFP shows that TnT3 facilitates Ca{sub v}β{sub 1a} nuclear recruitment, suggesting that the two proteins play a heretofore unknown role during early muscle differentiation in addition to their classical role in ECC regulation. - Highlights: • Previously, we demonstrated that Ca{sub v}β{sub 1a} is a gene transcription regulator. • Here, we show that TnT3 interacts with Ca{sub v}β{sub 1a}. • We mapped TnT3 and Ca{sub v}β{sub 1a} interaction domain. • TnT3 facilitates Ca{sub v}β{sub 1a} nuclear enrichment. • The two proteins play a heretofore unknown role during early muscle differentiation.

Troponin T3 regulates nuclear localization of the calcium channel Cavβ1a subunit in skeletal muscle

International Nuclear Information System (INIS)

Zhang, Tan; Taylor, Jackson; Jiang, Yang; Pereyra, Andrea S.; Messi, Maria Laura; Wang, Zhong-Min; Hereñú, Claudia; Delbono, Osvaldo

2015-01-01

The voltage-gated calcium channel (Ca v ) β 1a subunit (Ca v β 1a ) plays an important role in excitation–contraction coupling (ECC), a process in the myoplasm that leads to muscle-force generation. Recently, we discovered that the Ca v β 1a subunit travels to the nucleus of skeletal muscle cells where it helps to regulate gene transcription. To determine how it travels to the nucleus, we performed a yeast two-hybrid screening of the mouse fast skeletal muscle cDNA library and identified an interaction with troponin T3 (TnT3), which we subsequently confirmed by co-immunoprecipitation and co-localization assays in mouse skeletal muscle in vivo and in cultured C2C12 muscle cells. Interacting domains were mapped to the leucine zipper domain in TnT3 COOH-terminus (160–244 aa) and Ca v β 1a NH 2 -terminus (1–99 aa), respectively. The double fluorescence assay in C2C12 cells co-expressing TnT3/DsRed and Ca v β 1a /YFP shows that TnT3 facilitates Ca v β 1a nuclear recruitment, suggesting that the two proteins play a heretofore unknown role during early muscle differentiation in addition to their classical role in ECC regulation. - Highlights: • Previously, we demonstrated that Ca v β 1a is a gene transcription regulator. • Here, we show that TnT3 interacts with Ca v β 1a . • We mapped TnT3 and Ca v β 1a interaction domain. • TnT3 facilitates Ca v β 1a nuclear enrichment. • The two proteins play a heretofore unknown role during early muscle differentiation

A combination of troponin T and 12-lead electrocardiography: a valuable tool for early prediction of long-term mortality in patients with chest pain without ST-segment elevation.

Science.gov (United States)

Jernberg, Tomas; Lindahl, Bertil

2002-11-01

Electrocardiography (ECG) obtained on admission and a troponin T (tn-T) level measured early after admission are simple and accessible methods for predicting outcome in patients with suspected unstable angina or myocardial infarction without persistent ST-elevations. However, there are few studies about the combination of these 2 methods as a means of predicting long-term outcome. ECG was obtained on admission, and a tn-T level was analyzed on admission and after 6 hours in 710 consecutive patients admitted because of chest pain and no ST-elevations. Patients were observed for a median time of 40 months for death. ST-segment depressions > or =0.05 mV were present in 266 patients (37%). These patients had a 9.7-fold increased risk of death, compared with patients with normal ECG results. Isolated T-Wave inversions or pathological signs other than ST-T changes were present in 196 patients (28%), who had a 4.5-fold increased risk of death compared with patients who had normal ECG results. At 6 hours after admission, 169 patients (24%) had at least 1 sample of tn-T > or =0.10 microg/L, which resulted in an 3.7-fold increased risk of death. In a multivariate analysis, both ECG on admission and tn-T level came out as independent predictors of outcome. When these methods were combined, patients could be divided into low- (tn-T level or =0.10 microg/L or ST-segment depression), and high-risk groups (tn-T level > or =0.10 microg/L and ST-segment depression). ECG and tn-T level are valuable tools to quickly risk stratify patients with chest pain. The combination of these methods is superior to either one alone.

A new strategy for 2,4,6-Trinitrotoluene adsorption and electrochemical reduction on poly(melamine)/graphene oxide modified electrode

International Nuclear Information System (INIS)

Cotchim, Suparat; Thavarungkul, Panote; Kanatharana, Proespichaya; Limbut, Warakorn

2015-01-01

Highlights: • A new fabrication strategy of a poly(melamine)/graphene oxide (PM/GO) modified glassy carbon electrode (GCE) (PM/GO/GCE) for the detection of ultra-traces of TNT is proposed. • The PM/GO/GCE exhibits excellent adsorption and electrochemical reduction of TNT via the AdCSV technique. • The PM/GO/GCE provides for a high sensitivity, good repeatability and selectivity. • This strategy opens new opportunities for the sensitive detection of TNT aiming at protection of the environmental and homeland securities. - Abstract: A poly(melamine)/graphene oxide (PM/GO) layer modified on a glassy carbon electrode (GCE) was used for the adsorption and electrochemical detection of 2,4,6 trinitrotoluene (TNT). The surface morphology and electrochemical behaviour of the PM/GO/GCE were characterized by scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR), cyclic voltammetry (CV) and adsorptive cathodic stripping voltammetry (AdCSV). The PM/GO/GCE exhibited excellent adsorption and electrochemical reduction of TNT via the AdCSV technique with two linear ranges, 1–90 μg L −1 and 100–1000 μg L −1 , a detection limit of 0.34 μg L −1 and a quantitation limit of 1.14 μg L −1 . The PM/GO/GCE provided for a high sensitivity, good repeatability and selectivity. This modified electrode was successfully applied to detect TNT in soil samples with good recoveries that ranged from 93 to 99%.

Highly Sensitive Ratiometric Fluorescent Sensor for Trinitrotoluene Based on the Inner Filter Effect between Gold Nanoparticles and Fluorescent Nanoparticles.

Science.gov (United States)

Lu, Hongzhi; Quan, Shuai; Xu, Shoufang

2017-11-08

In this work, we developed a simple and sensitive ratiometric fluorescent assay for sensing trinitrotoluene (TNT) based on the inner filter effect (IFE) between gold nanoparticles (AuNPs) and ratiometric fluorescent nanoparticles (RFNs), which was designed by hybridizing green emissive carbon dots (CDs) and red emissive quantum dots (QDs) into a silica sphere as a fluorophore pair. AuNPs in their dispersion state can be a powerful absorber to quench CDs, while the aggregated AuNPs can quench QDs in the IFE-based fluorescent assays as a result of complementary overlap between the absorption spectrum of AuNPs and emission spectrum of RFNs. As a result of the fact that TNT can induce the aggregation of AuNPs, with the addition of TNT, the fluorescent of QDs can be quenched, while the fluorescent of CDs would be recovered. Then, ratiometric fluorescent detection of TNT is feasible. The present IFE-based ratiometric fluorescent sensor can detect TNT ranging from 0.1 to 270 nM, with a detection limit of 0.029 nM. In addition, the developed method was successfully applied to investigate TNT in water and soil samples with satisfactory recoveries ranging from 95 to 103%, with precision below 4.5%. The simple sensing approach proposed here could improve the sensitivity of colorimetric analysis by changing the ultraviolet analysis to ratiometric fluorescent analysis and promote the development of a dual-mode detection system.

The Bioactivity and Photocatalytic Properties of Titania Nanotube Coatings Produced with the Use of the Low-Potential Anodization of Ti6Al4V Alloy Surface

Science.gov (United States)

Radtke, Aleksandra; Kozak, Wiesław; Sadowska, Beata; Więckowska-Szakiel, Marzena; Szubka, Magdalena; Talik, Ewa; Pleth Nielsen, Lars; Piszczek, Piotr

2017-01-01

Titania nanotube (TNT) coatings were produced using low-potential anodic oxidation of Ti6Al4V substrates in the potential range 3–20 V. They were analysed by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The wettability was estimated by measuring the contact angle when applying water droplets. The bioactivity of the TNT coatings was established on the basis of the biointegration assay (L929 murine fibroblasts adhesion and proliferation) and antibacterial tests against Staphylococcus aureus (ATCC 29213). The photocatalytic efficiency of the TNT films was studied by the degradation of methylene blue under UV irradiation. Among the studied coatings, the TiO2 nanotubes obtained with the use of 5 V potential (TNT5) were found to be the most appropriate for medical applications. The TNT5 sample possessed antibiofilm properties without enriching it by additional antimicrobial agent. Furthermore, it was characterized by optimal biocompatibility, performing better than pure Ti6Al4V alloy. Moreover, the same sample was the most photocatalytically active and exhibited the potential for the sterilization of implants with the use of UV light and for other environmental applications. PMID:28933732

The Bioactivity and Photocatalytic Properties of Titania Nanotube Coatings Produced with the Use of the Low-Potential Anodization of Ti6Al4V Alloy Surface.

Science.gov (United States)

Radtke, Aleksandra; Topolski, Adrian; Jędrzejewski, Tomasz; Kozak, Wiesław; Sadowska, Beata; Więckowska-Szakiel, Marzena; Szubka, Magdalena; Talik, Ewa; Pleth Nielsen, Lars; Piszczek, Piotr

2017-07-26

Titania nanotube (TNT) coatings were produced using low-potential anodic oxidation of Ti6Al4V substrates in the potential range 3-20 V. They were analysed by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The wettability was estimated by measuring the contact angle when applying water droplets. The bioactivity of the TNT coatings was established on the basis of the biointegration assay (L929 murine fibroblasts adhesion and proliferation) and antibacterial tests against Staphylococcus aureus (ATCC 29213). The photocatalytic efficiency of the TNT films was studied by the degradation of methylene blue under UV irradiation. Among the studied coatings, the TiO₂ nanotubes obtained with the use of 5 V potential (TNT5) were found to be the most appropriate for medical applications. The TNT5 sample possessed antibiofilm properties without enriching it by additional antimicrobial agent. Furthermore, it was characterized by optimal biocompatibility, performing better than pure Ti6Al4V alloy. Moreover, the same sample was the most photocatalytically active and exhibited the potential for the sterilization of implants with the use of UV light and for other environmental applications.

Sodium fluoride-assisted modulation of anodized TiO₂ nanotube for dye-sensitized solar cells application.

Science.gov (United States)

Yun, Jung-Ho; Ng, Yun Hau; Ye, Changhui; Mozer, Attila J; Wallace, Gordon G; Amal, Rose

2011-05-01

This work reports the use of sodium fluoride (in ethylene glycol electrolyte) as the replacement of hydrofluoric acid and ammonium fluoride to fabricate long and perpendicularly well-aligned TiO₂ nanotube (TNT) (up to 21 μm) using anodization. Anodizing duration, applied voltage and electrolyte composition influenced the geometry and surface morphologies of TNT. The growth mechanism of TNT is interpreted by analyzing the current transient profile and the total charge density generated during anodization. The system with low water content (2 wt %) yielded a membrane-like mesoporous TiO₂ film, whereas high anodizing voltage (70 V) resulted in the unstable film of TNT arrays. An optimized condition using 5 wt % water content and 60 V of anodizing voltage gave a stable array of nanotube with controllable length and pore diameter. Upon photoexcitation, TNTs synthesized under this condition exhibited a slower charge recombination rate as nanotube length increased. When made into cis-diisothiocyanato-bis(2,2̀-bipyridyl-4,4̀-dicarboxylato) ruthenium(II) bis (tetrabutyl-ammonium)(N719) dye-sensitized solar cells, good device efficiency at 3.33 % based on the optimized TNT arrays was achieved with longer electron time compared with most mesoporous TiO₂ films.

Solute transport and extraction by a single root in unsaturated soils: model development and experiment

Energy Technology Data Exchange (ETDEWEB)

Kim, Jaisoo; Sung, Kijune; Corapcioglu, M. Yavuz; Drew, Malcolm C

2004-09-01

A contaminant transport model was developed to simulate the fate and transport of organic compounds such as TNT (2,4,6-trinitrotoluene), using the single-root system. Onions were planted for this system with 50-ml plastic tubes. Mass in the soil, soil solution, root and leaf was monitored using {sup 14}C-TNT. Model parameters were acquired from the experiments in the single-root system and were used to simulate total TNT concentration in soil, providing the average concentrations in the rhizosphere and bulk soil as well as root and leaf compartments. Because the existing RCF (root concentration factor) and TSCF (transpiration stream concentration factor) equations based on log K{sub ow} (octanol-water partition coefficient) were not correlated to TNT uptake, a new term, root uptake rate (R{sub ur}), and a new T{sub scf} equation, based on the experimental data, were introduced in the proposed model. The results from both modeling and experimental studies showed higher concentrations of TNT in the rhizosphere than in the bulk soil, because mass transported from the surrounding soil into the rhizosphere was higher than that by root uptake.

Fabrication of surface plasmon resonance sensor surface with control of the nonspecific adsorption and affinity for the detection of 2,4,6-trinitrotoluene using an antifouling copolymer

Directory of Open Access Journals (Sweden)

Rui eYatabe

2014-04-01

Full Text Available We fabricated a surface plasmon resonance (SPR sensor using a hydrophilic polymer for the highly sensitive detection of 2,4,6-trinitrotoluene (TNT. The hydrophilic polymer was made from mono-2-(methacryloyloxyethylsuccinate (MES and 2-hydroxyethylmethacrylate (HEMA by surface-initiated atom transfer radical polymerization (SI-ATRP. The detection of TNT was carried out by displacement assay with the SPR measurement. In displacement assay, the affinity between anti-TNT antibody and the sensor surface, affects to the sensitivity. In the SPR measurement, nonspecific adsorption should be controlled because SPR sensor cannot discriminate between specific and nonspecific adsorption. Therefore, the affinity and nonspecific adsorption were controlled by changing the ratio of HEMA to MES. A detection limit of 0.4 ng/ml (ppb for TNT was achieved using a sensor surface with the lowest affinity without nonspecific adsorption.

Forensic Analysis of High Explosive Residues from Selected Cloth

International Nuclear Information System (INIS)

Mohamad Afiq Mohamed Huri; Umi Kalthom Ahmad

2014-01-01

Increased terrorist activities around the Asian region have resulted in the need for improved analytical techniques in forensic analysis. High explosive residues from post-blast clothing are often encountered as physical evidence submitted to a forensic laboratory. Therefore, this study was initiated to detect high explosives residues of cyclotrimethylenetrinitramine (RDX) and pentaerythritol tetranitrate (PETN) on selected cloth in this study. Cotton swabbing technique was employed as a simple and rapid method in recovering analytes from the sample matrix. Analytes were analyzed using Griess spot test, TLC and HPLC. TLC separation employed toluene-ethyl acetate (9:1) as a good solvent system. Reversed phase HPLC separation employed acetonitrile-water (65:35) as the mobile phase and analytes detected using a programmed wavelength. RDX was detected at 235 nm for the first 3.5 min and then switched to 215 nm for PETN. Limits of detection (LODs) of analytes were in the low ppm range (0.05 ppm for RDX and 0.25 ppm for PETN). Analyte recovery studies revealed that the type of cloth has a profound effect on the extraction efficiency. Analytes were recovered better for nylon as compared to cotton cloth. However, no analytes could be recovered from denim cloth. For post-blast samples, only RDX was detected in low concentration for both nylon and cotton cloth. (author)

SAGE ANALYSIS OF TRANSCRIPTOME RESPONSES IN ARABIDOPSIS ROOTS EXPOSED TO 2,4,6-TRINITROTOLUENE

Science.gov (United States)

Serial Analysis of Gene Expression (SAGE) was used to profile transcript levels in Arabidopsis thaliana roots and assess their responses to 2,4,6-trinitrotoluene (TNT) exposure. SAGE libraries representing control and TNT-exposed seedling root transcripts were constructed, and ea...

Development of Toxicity Benchmarks and Bioaccumulation Data for N-based Organic Explosives for Terrestrial Plants and Soil Invertebrates

Science.gov (United States)

2012-11-01

mL pre-weighed glass vessel. The sample was then completely evaporated using a nitrogen stream and the vessel was placed in an oven at 150°C for 1 h...14]. Central nervous system and respiratory distresses also were observed in the RDX-exposed birds . In humans, RDX is a possible carcinogen, and...failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO

Acute hexogen poisoning after occupational exposure.

Science.gov (United States)

Testud, F; Glanclaude, J M; Descotes, J

1996-01-01

Hexogen (cyclonite, RDX) nitrate explosive is an infrequent cause of poisoning. A 42-year-old man with no prior history of epilepsy experienced grand mal seizures after sieving fine hexogen (RDX) powder for four hours in an ammunition plant. Physical examination was normal on arrival at the emergency room but recurrent seizures occurred six hour after admission. EEG, CT scan and MRI were normal and the patient recovered uneventfully. The available toxicological data on this rare occupational poisoning are reviewed.

Integrated Data Collection Analysis (IDCA) Program — KClO₃/Icing Sugar (-100 mesh) Mixture

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (IHD-NSWC), Indian Head, MD (United States). Indian Head Division; Sorenson, Daniel N. [Naval Surface Warfare Center (IHD-NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (IHD-NSWC), Indian Head, MD (United States). Indian Head Division; Moran, Jesse S. [Naval Surface Warfare Center (IHD-NSWC), Indian Head, MD (United States). Indian Head Division; Shelley, Timothy J. [Air Force Research Lab. (AFRL/RXQF), Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whipple, Richard E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2011-05-02

The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small-Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and scanning calorimetry analysis of a mixture of KClO₃ sized through a 100-mesh sieve mixed with icing sugar, also sized through a 100-mesh sieve—KClO₃/icing sugar (-100) mixture. This material was selected because of the challenge of performing SSST testing of a mixture of two solid materials. The mixture was found to be: 1) more sensitive to impact than RDX, with sensitivity similar to PETN, 2) the same or more sensitive to friction than PETN, and 3) less sensitive to spark than RDX. The analysis showed that the mixture has thermally stability similar to RDX and is perhaps more energetic upon decomposition but variable results indicate sampling issues.

EDS V25 containment vessel explosive qualification test report.

Energy Technology Data Exchange (ETDEWEB)

Rudolphi, John Joseph

2012-04-01

The V25 containment vessel was procured by the Project Manager, Non-Stockpile Chemical Materiel (PMNSCM) as a replacement vessel for use on the P2 Explosive Destruction Systems. It is the first EDS vessel to be fabricated under Code Case 2564 of the ASME Boiler and Pressure Vessel Code, which provides rules for the design of impulsively loaded vessels. The explosive rating for the vessel based on the Code Case is nine (9) pounds TNT-equivalent for up to 637 detonations. This limit is an increase from the 4.8 pounds TNT-equivalency rating for previous vessels. This report describes the explosive qualification tests that were performed in the vessel as part of the process for qualifying the vessel for explosive use. The tests consisted of a 11.25 pound TNT equivalent bare charge detonation followed by a 9 pound TNT equivalent detonation.

TiO2 Nanotube Arrays Composite Film as Photoanode for High-Efficiency Dye-Sensitized Solar Cell

Directory of Open Access Journals (Sweden)

Jinghua Hu

2014-01-01

Full Text Available A double-layered photoanode made of hierarchical TiO2 nanotube arrays (TNT-arrays as the overlayer and commercial-grade TiO2 nanoparticles (P25 as the underlayer is designed for dye-sensitized solar cells (DSSCs. Crystallized free-standing TNT-arrays films are prepared by two-step anodization process. For photovoltaic applications, DSSCs based on double-layered photoanodes produce a remarkably enhanced power conversion efficiency (PCE of up to 6.32% compared with the DSSCs solely composed of TNT-arrays (5.18% or nanoparticles (3.65% with a similar thickness (24 μm at a constant irradiation of 100 mW cm−2. This is mainly attributed to the fast charge transport paths and superior light-scattering ability of TNT-arrays overlayer and good electronic contact with F-doped tin oxide (FTO glass provided from P25 nanoparticles as a bonding layer.

Field Characterization for Remediation of Trinitrotoluene in Sediment and Water from Vieques, Puerto Rico

Science.gov (United States)

Echols, E. L.; Carvalho-Knighton, K. M.; Pyrtle, A. J.

2007-12-01

2,4,6-Trinitrotoluene (TNT) is an explosive used in military shells, bombs, and grenades, industrial applications, and underwater blasting. The explosive itself, some of its degradation and transformation products, and any manufacturing impurities or by-products are all considered serious environmental contaminants with potential harmful and toxic effects on animals, plants and humans. In Vieques, Puerto Rico, The Atlantic Fleet Weapons Training Area consists of areas and nearby waters that have become contaminated primarily by United States Department of Defense (DoD) activities. Known areas of concern include waters influenced by target practice off the eastern shores of Vieques, areas where ships were anchored north of Vieques, and waters near the western side of Vieques, including Mosquito Pier. Detection and remediation of TNT in these areas is necessary to protect the health and welfare of the present and future Vieques residents and visitors. This work examines the distribution of TNT at specific locations in Vieques. Samples were collected from Mosquito Bay which is located in the watershed between the residential and naval sections of Vieques and also in a northern section of the island at Kiani Lagoon. In addition to Vieques sediment studies, the use of zero-valent iron (ZVI) to degrade trinitrotoluene was examined. The ultimate focus is on emulsifying ZVI particles that are capable of promoting rapid and complete degradation of TNT molecules. ZVI has demonstrated effective degradation of TNT, however, these particles by themselves have significant problems in treating sorbed phase TNT. Results from these studies will be presented.

Enhanced photocatalytic degradation activity over TiO{sub 2} nanotubes co-sensitized by reduced graphene oxide and copper(II) meso-tetra(4-carboxyphenyl)porphyrin

Energy Technology Data Exchange (ETDEWEB)

Wei, Meng; Wan, Junmin, E-mail: wwjm2001@126.com; Hu, Zhiwen; Peng, Zhiqin; Wang, Bing

2016-07-30

Highlights: • CuTCPP/rGO-TNT photocatalysts are synthesized. • CuTCPP and rGO are helpful to induce interfacial charge transfer at surface junction. • CuTCPP and rGO are favorable for enhancing co-photocatalytic activity. • A deeper insight into the co-photocatalytic mechanism is put forward. • The photocatalyst are proven to be effective and chemically-stable catalysts. - Abstract: In this paper, TiO{sub 2} nanotubes (TNT) co-sensitized with copper(II) meso-tetra(4-carboxyphenyl)porphyrin (CuTCPP) and reduced graphene oxide nanosheets (rGO), which was fabricated through two-step improved hydrothermal method and heating reflux process. The effect of rGO and CuTCPP on the co-photocatalytic behavior of TNT for the degradation of Methylene Blue (MB) were measured under visible light irradiation. The photocatalysts have been characterized and analyzed by high-resolution transmission electron microscopy (TEM), selected area electronic diffraction (SAED), elemental mapping by energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) and electron paramagnetic resonance (EPR). The results provide a deeper insight into the co-photocatalytic mechanism of CuTCPP/rGO-TNT nanocomposites. The degradation results showed a purification of more than 95% MB in wastewater, which is about 5 times higher than that of the pure TNT. The results also confirm the prepared CuTCPP/rGO-TNT nanocomposites possess superior co-photocatalytic activities.

Safety vessels for explosive fusion reactor

International Nuclear Information System (INIS)

Mineev, V.

1994-01-01

The failure of several types of geometrically similar cylindrical and spherical steel and glass fibers vessels filled with water or air was investigated when an explosive charge of TNT was detonated in the center. Vessels had radius 50-1000 mm, thickness of walls 2-20%. The detonation on TNT imitated energy release. The parameter: K = M/mf is a measure of the strength of the vessel where M is the mass of the vessel, and mf is the mass of TNT for which the vessel fails. This demanded 2-4 destroyed and nondestroyed shots. It may be showed that: K=A/σ f where σ f is the fracture stress of the material vessel, and A = const = F(energy TNT, characteristic of elasticity of vessel material). The chief results are the following: (1) A similar increase in the geometrical dimensions of steel vessels by a factor of 10 leads to the increase of parameter K in about 5 times and to decrease of failure deformation in 7 times (scale effect). (2) For glass fibers, scale effect is absent. (3) This problem is solved in terms of theory energetic scale effect. (4) The concept of TNT equivalent explosive makes it possible to use these investigations to evaluate the response of safety vessels for explosive fusion reactor

Bioremediation of trinitrotolulene by a ruminal microorganism

Energy Technology Data Exchange (ETDEWEB)

Lee, Taejin; Williamson, K.J.; Craig, A.M. [Oregon State Univ., Corvallis, OR (United States)

1995-10-01

2,4,6-trinitrotoluene (TNT) has been widely used for the production of explosives because of its low boiling point, high stability, low impact sensitivity, and safe manufacture. More than 1,100 military facilities, each potentially contaminated with munitions waste, are expected to require treatment of more than one million cubic yards of contaminated soils. The cost associated with remediation of these sites has been estimated to be in excess of $1.5 billion. Recently, researchers have studied ruminal microorganisms in relation to their ability to degrade xenobiotic compounds. Many of these organisms are strict anaerobes with optimal redox potentials as low as -420 mV. Ruminal organisms have been shown capable of destroying some pesticides, such as parathion, p-nitrophenol, and biphenyl-type compounds; thiono isomers, and nitrogen-containing heterocyclic plant toxins such as the pyrrolizidine alkaloids. Many of these compounds have structures similar to TNT. A TNT-degrading ruminal microorganism has been isolated from goat rumen fluid with successive enrichments on triaminotoluene (TAT) and TNT. The isolate, designated G.8, utilizes nitrate and lactate as the primary energy source. G.8 was able to tolerate and metabolite levels of TNT up to the saturation point of 125 mg/l.

Electropolymerization of polyaniline on titanium oxide nanotubes for supercapacitor application

International Nuclear Information System (INIS)

Mujawar, Sarfraj H.; Ambade, Swapnil B.; Battumur, T.; Ambade, Rohan B.; Lee, Soo-Hyoung

2011-01-01

Highlights: → Polyaniline (PANI)-Titanium nanotube template (TNT) composite for supercapacitors. → The mechanism of the controlled growth of hollow open ended PANI nanotubes using a TNT template is studied. → A rare effort to electropolymerise PANI on TNTs resulting into an appreciable capacitance of 740 F g -1 . - Abstract: Vertically aligned polyaniline (PANI) nanotubes have great potential application in supercapacitor electrode material. In this paper we have investigated facile growth of PANI nanotubes on a titanium nanotube template (TNT) using electrochemical polymerization. The morphology of PANI nanostructures grown over TNT is strongly influenced by the scan rate in the electrochemical polymerization. The growth morphology of PANI nanotubes has been carefully analyzed by field emission scanning electron microscopy. The detailed growth mechanism of PANI nanotubes has been put forward. Specific capacitance value of 740 F g -1 was obtained for PANI nanotube structures (measured at charge-discharge rate of 3 A g -1 ).

Do not respond! Doing the think/no-think and go/no-go task concurrently leads to memory impairment of unpleasant items during later recall

Directory of Open Access Journals (Sweden)

Cornelia eHerbert

2012-08-01

Full Text Available Previous research using neuroimaging methods proposed a link between mechanisms controlling motor response inhibition and suppression of unwanted memories. The present study investigated this hypothesis behaviorally by combining the think-no-think paradigm (TNT with a go/no-go motor inhibition task. Participants first learned unpleasant cue-target pairs. Cue words were then presented as go or no-go items in the TNT. Participants’ task was to respond to the cues and think of the target word aloud or to inhibit their response to the cue and the target word from coming to mind. Cued recall assessed immediately after the TNT revealed reduced recall performance for no-go targets compared to go targets or baseline cues, not presented in the TNT. The results demonstrate that doing the no-think and no-go task concurrently leads to memory suppression of unpleasant items during later recall. Results are discussed in line with recent empirical research and theoretical positions.

Radioimmunoimaging of tumors with a pantumor antibody

International Nuclear Information System (INIS)

Chen, D.C.P.; Siegel, M.E.; Chen, F.; Taylor, O.R.; Epstein, A.L.

1988-01-01

The TNT-1 antibody was developed to bind intracellular nuclear antigens that are accessible only in degenerative or necrotic cells. Since about 50% of tumor cells are in various stages of cell degeneration or death, this antibody could serve as a pantumor antibody for tumor detection. After intravenous injection of 10 μg of TNT-1F(ab')2 fragments labeled with 20 μCi of I-131, serial images were obtained at 1 and 4 hours and daily for 6 days in mice bearing various human tumors. Accumulation of TNT-1 was imaged in a necrotic tumor as early as 4 hours after injection and because more intense at 48 hours. The tumor-muscle ratio was as high as 29:1. Intense accumulation was noted in the necrotic tumor, about nine times that of healthy tumor. In conclusion, TNT-1, a pantumor antibody, can detect necrotic tumors in animal models. It may be an ideal imaging agent for cancer detection

Feasibility of landmine detection using transgenic plants

Science.gov (United States)

Deyholos, Michael; Faust, Anthony A.; Miao, Minmin; Montoya, Rebecca; Donahue, D. Aaron

2006-05-01

Genetically modified plants that detect TNT and its degradation products are potentially powerful aids in humanitarian demining and detection of unexploded ordnance. Although the feasibility of TNT detection by plants and microorganisms has been demonstrated by several research teams world wide, thus far, none of these previously demonstrated systems has the sensitivity and specificity to be effective under field conditions. We are using two approaches to increase the potential effectiveness of these and related biological detection systems. First, we are expanding the repertoire of explosive-responsive promoters by conducting DNA microarray experiments with plants treated with TNT-degradation products, and characterizing the inducibility of reporter gene expression by these promoters. Second, we are evaluating the dynamics and limiting factors in the transmission of artificial signals from roots to shoots. This will increase the ability of soil-based TNT perception strategies to effect human-readable changes in shoot morphology as part of a practical plant-based explosives detection system.

Blast characteristics of firework mixture, 'Raiyaku'. Raiyaku no bakufuatsu

Energy Technology Data Exchange (ETDEWEB)

Iida, M.; Nakayama, Y.; Matsunaga, T.; Tanaka, K.; Yoshida, M.; Kakudate, Y.; Usuba, S.; Fujiwara, S. (National Chemical Lab. for Industry, Tsukuba (Japan))

1991-10-31

Raiyaku, as a type of raw material for explosive, are very dangerous , has high explosive power but there are difficulties in dretermining blast characteristics in terms of TNT equivalence. This study was made using raiyaku, firework mixture of 70 wt % potassium perchlorate, 15 wt % aluminium powder and 15 wt % titanium Powder. Blast characteristics of the raiyaku were studied exploding 1 Kg of the mixture in the sky and 30 Kg and 50 Kg in the surface at range in scaled distance from 1 to 15 m/kg{sup (1/3)} using piezoelectric gauges and lead-Plate blastmeters. As blast characteristics, equivalence was determined on the basis of measured Peak overpressures. Scaled distances when ploted against TNT equivalence, it has been cleared that TNT equivalence was 52.2 % on average with standard error of 8.4 %. Further it was clear that with the increase of equivalent distance TNT equivalence has increased from about 40 % to 60 %. 10 refs., 4 figs., 3 tabs.

Improved Metastasis- and Disease-Free Survival With Preoperative Sequential Short-Course Radiation Therapy and FOLFOX Chemotherapy for Rectal Cancer Compared With Neoadjuvant Long-Course Chemoradiotherapy: Results of a Matched Pair Analysis.

Science.gov (United States)

Markovina, Stephanie; Youssef, Fady; Roy, Amit; Aggarwal, Sonya; Khwaja, Shariq; DeWees, Todd; Tan, Benjamin; Hunt, Steven; Myerson, Robert J; Chang, Daniel T; Parikh, Parag J; Olsen, Jeffrey R

2017-10-01

To compare treatment and toxicity outcomes between a phase 2 institutional trial of near total neoadjuvant therapy (nTNT) for locally advanced rectal cancer and a similar historical control cohort treated at Washington University in St. Louis with the current US standard of care, defined as neoadjuvant chemoradiotherapy (NCRT), total mesorectal excision (TME), and adjuvant FOLFOX chemotherapy; to expand the comparison to an additional institution, patients treated with similar NCRT at Stanford University were included. Sixty-nine patients with cT3-4N0-2M0 rectal adenocarcinoma enrolled on the Washington University in St. Louis phase 2 study of nTNT were included for analysis. Patients treated at the same institution with conventional NCRT and adjuvant FOLFOX were matched for exact cTNM stage. Forty-one patients treated with NCRT at Stanford University were included in a second analysis. Kaplan-Meier analysis with log-rank test was used to compare local control, distant metastasis-free survival, disease-free survival, and overall survival. Median follow-up was 49 and 54 months for nTNT and NCRT, respectively. Pathologic complete response and T-downstaging rates were 28% versus 16% (P=.21) and 75% versus 41% (P<.001) in the nTNT and NCRT cohorts, respectively. Three-year disease-free survival (85% vs 68%, P=.032) was significantly better in the nTNT group. Actuarial 3-year local control (92% vs 96%, P=.36) and overall survival (96% vs 88%, P=.67) were similar. The Stanford cohort had significantly lower clinical stage. After controlling for clinical stage, age, tumor location, institution, and number of chemotherapy cycles, nTNT treatment remained significantly associated with lower risk of recurrence (P=.006). Patients treated with nTNT had higher T-downstaging and superior distant metastasis-free survival and disease-free survival compared with conventional NCRT when matched for tumor location and exact cTNM stage. Near total neoadjuvant therapy remained a

Troponin C Mutations Partially Stabilize the Active State of Regulated Actin and Fully Stabilize the Active State When Paired with Δ14 TnT.

Science.gov (United States)

Baxley, Tamatha; Johnson, Dylan; Pinto, Jose R; Chalovich, Joseph M

2017-06-13

Striated muscle contraction is regulated by the actin-associated proteins tropomyosin and troponin. The extent of activation of myosin ATPase activity is lowest in the absence of both Ca 2+ and activating cross-bridges (i.e., S1-ADP or rigor S1). Binding of activating species of myosin to actin at a saturating Ca 2+ concentration stabilizes the most active state (M state) of the actin-tropomyosin-troponin complex (regulated actin). Ca 2+ binding alone produces partial stabilization of the active state. The extent of stabilization at a saturating Ca 2+ concentration depends on the isoform of the troponin subunits, the phosphorylation state of troponin, and, in the case of cardiac muscle, the presence of hypertrophic cardiomyopathy-producing mutants of troponin T and troponin I. Cardiac dysfunction is also associated with mutations of troponin C (TnC). Troponin C mutants A8V, C84Y, and D145E increase the Ca 2+ sensitivity of ATPase activity. We show that these mutants change the distribution of regulated actin states. The A8V and C84Y TnC mutants decreased the inactive B state distribution slightly at low Ca 2+ concentrations, but the D145E mutants had no effect on that state. All TnC mutants increased the level of the active M state compared to that of the wild type, at a saturating Ca 2+ concentration. Troponin complexes that contained two mutations that stabilize the active M state, A8V TnC and Δ14 TnT, appeared to be completely in the active state in the presence of only Ca 2+ . Because Ca 2+ gives full activation, in this situation, troponin must be capable of positioning tropomyosin in the active M state without the need for rigor myosin binding.

A Novel Investigation of the Formation of Titanium Oxide Nanotubes on Thermally Formed Oxide of Ti-6Al-4V.

Science.gov (United States)

Butt, Arman; Hamlekhan, Azhang; Patel, Sweetu; Royhman, Dmitry; Sukotjo, Cortino; Mathew, Mathew T; Shokuhfar, Tolou; Takoudis, Christos

2015-10-01

Traditionally, titanium oxide (TiO2) nanotubes (TNTs) are anodized on Ti-6Al-4V alloy (Ti-V) surfaces with native TiO2 (amorphous TiO2); subsequent heat treatment of anodized surfaces has been observed to enhance cellular response. As-is bulk Ti-V, however, is often subjected to heat treatment, such as thermal oxidation (TO), to improve its mechanical properties. Thermal oxidation treatment of Ti-V at temperatures greater than 200°C and 400°C initiates the formation of anatase and rutile TiO2, respectively, which can affect TNT formation. This study aims at understanding the TNT formation mechanism on Ti-V surfaces with TO-formed TiO2 compared with that on as-is Ti-V surfaces with native oxide. Thermal oxidation-formed TiO2 can affect TNT formation and surface wettability because TO-formed TiO2 is expected to be part of the TNT structure. Surface characterization was carried out with field emission scanning electron microscopy, energy dispersive x-ray spectroscopy, water contact angle measurements, and white light interferometry. The TNTs were formed on control and 300°C and 600°C TO-treated Ti-V samples, and significant differences in TNT lengths and surface morphology were observed. No difference in elemental composition was found. Thermal oxidation and TO/anodization treatments produced hydrophilic surfaces, while hydrophobic behavior was observed over time (aging) for all samples. Reduced hydrophobic behavior was observed for TO/anodized samples when compared with control, control/anodized, and TO-treated samples. A method for improved surface wettability and TNT morphology is therefore discussed for possible applications in effective osseointegration of dental and orthopedic implants.

Phytoremediation of explosives for laboratory to real application

Energy Technology Data Exchange (ETDEWEB)

Vanek, T.; Vavrikova, Z.; Podlipna, R. [Inst. of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague (Czech Republic). Dept. of Plant Tissue Cultures; Gerth, A. [BioPlanta GmbH, Leipzig (Germany)

2006-07-01

This paper discussed the phytoremediation of 2,4,6-trinitrotoluene (TNT) contaminated soil at former ammunition factories in the Czech Republic and Germany. The uptake, degradation, and distribution of the compounds in various plants were evaluated. Characterization and identification of TNT degradation products is difficult due to the insoluble fractions bound in the plant cells. Rheum palmatum culture was supplemented with naphthaleneacetic acid and casein hydrolysate. The plant species Phragmites australis and Typha latifolia were cultivated and supplemented with vitamins. Roots were induced on the hormone-free medium during a 4 to 5 week cultivation period. 2,4,6-trinitrotoluene, glyceroltrinitrate and pentaerytritoltetranitrate were obtained from an ammunition factory. Explosives were added into the cultivation medium at a concentration of 50 mg/l during the first part of the experiment, as well as repeatedly at 10 and 50 mg/l during the second part of the experiment. The uptake of TNT by R. palmatum was determined over 24 hours. The initial concentration of TNT decreased to 50 per cent within half an hour. No TNT could be detected after 6 hours. At least 90 per cent of TNT was taken up by the plant species Phragmites, Typha and Juncus in 10 days. Faster uptake was determined in plants with roots. Phragmites australis was recommended as the best candidate for practical application as it forms a prolific biomass necessary for efficient biodegradation and is able to grow almost everywhere. A pilot-scale installation of constructed wetland containing nitroester explosives showed that the plants were able to clean water containing 270 mg/l of nitroesters and their by-products over a period of 30 days. 38 refs., 8 figs.

Acetaminophen and non-steroidal anti-inflammatory drugs interact with morphine and tramadol analgesia for the treatment of neuropathic pain in rats.

Science.gov (United States)

Shinozaki, Tomonari; Yamada, Toshihiko; Nonaka, Takahiro; Yamamoto, Tatsuo

2015-06-01

Although non-steroidal anti-inflammatory drugs and acetaminophen have no proven efficacy against neuropathic pain, they are frequently prescribed for neuropathic pain patients. We examined whether the combination of opioids (tramadol and morphine) with indomethacin or acetaminophen produce favorable effects on neuropathic pain and compared the efficacy for neuropathic pain with that for inflammatory pain. The carrageenan model was used as the inflammatory pain model while the tibial neuroma transposition (TNT) model was used as the neuropathic pain model. The tibial nerve is transected in the TNT model, with the tibial nerve stump then transpositioned to the lateral aspect of the hindlimb. Neuropathic pain (mechanical allodynia and neuroma pain) is observed after TNT injury. Drugs were administered orally. In the carrageenan model, all drugs produced anti-allodynic effects and all drug combinations, but not tramadol + indomethacin combination, produced synergistic anti-allodynic effects. In the TNT model, tramadol and morphine, but not acetaminophen and indomethacin, produced anti-neuropathic pain effects. In the combination, with the exception of morphine + acetaminophen combination, both acetaminophen and indomethacin reduced the 50% effective dose (ED50) of tramadol and morphine as compared with the ED50s for the single drug study in the TNT model. The ED50s of tramadol and morphine in the carrageenan combination test were not statistically significantly different from the ED50s in the TNT model combination study. The combination of opioids with indomethacin or acetaminophen produced a synergistic analgesic effect both in inflammatory and neuropathic pain with some exceptions. The efficacy of these combinations for neuropathic pain was not different from that for inflammatory pain.

The preparation, surface structure, zeta potential, surface charge density and photocatalytic activity of TiO2 nanostructures of different shapes

Science.gov (United States)

Grover, Inderpreet Singh; Singh, Satnam; Pal, Bonamali

2013-09-01

Titania based nanocatalysts such as sodium titanates of different morphology having superior surface properties are getting wide importance in photocatalysis research. Despite having sodium (Na) contents and its high temperature synthesis (that generally deteriorate the photoreactivity), these Na-titanates often exhibit better photoactivity than P25-TiO2 catalyst. Hence, this work demonstrated the influence of crystal structure, BET surface area, surface charge, zeta potential (ζ) and metal loading on the photocatalytic activity of as-prepared sodium titanate nanotube (TNT) and titania nanorod (TNR). Straw like hollow orthorhombic-TNT (Na2Ti2O5·H2O) particles (W = 9-12 nm and L = 82-115 nm) and rice like pure anatase-TNR particles (W = 8-13 nm and L = 81-134 nm) are obtained by the hydrothermal treatment of P25-TiO2 with NaOH, which in fact, altered the net surface charge of TNT and TNR particles. The observed ζ = -2.82 (P25-TiO2), -13.5 (TNT) and -22.5 mV (TNR) are significantly altered by the Ag and Cu deposition. It has been found here that TNT displayed best photocatalytic activity for the imidacloprid insecticide (C9H10ClN5O2) degradation to CO2 formation under UV irradiation because of its largest surface area 176 m2 g-1 among the catalysts studied.

Amine functionalized graphene oxide/CNT nanocomposite for ultrasensitive electrochemical detection of trinitrotoluene

Energy Technology Data Exchange (ETDEWEB)

Sablok, Kavita; Bhalla, Vijayender; Sharma, Priyanka; Kaushal, Roohi; Chaudhary, Shilpa [Institute of Microbial Technology (CSIR) Sector-39A, Chandigarh160036 (India); Suri, C. Raman, E-mail: raman@imtech.res.in [Institute of Microbial Technology (CSIR) Sector-39A, Chandigarh160036 (India)

2013-03-15

Highlights: ► Binding of electron-deficient trinitrotoluene to the electron rich amino groups to form JM complexes. ► rGO/CNT based platform for enhanced electrochemical detection. ► Functionalization and characterization of rGO/CNT with amine derivative. ► Ultrasenstitive and specific detection of TNT. -- Abstract: Binding of electron-deficient trinitrotoluene (TNT) to the electron rich amine groups on a substrate form specific charge-transfer Jackson–Meisenheimer (JM) complex. In the present work, we report formation of specific JM complex on amine functionalized reduced graphene oxide/carbon nanotubes- (a-rGO/CNT) nanocomposite leading to sensitive detection of TNT. The CNT were dispersed using graphene oxide that provides excellent dispersion by attaching to CNT through its hydrophobic domains and solubilizes through the available -OH and -COOH groups on screen printed electrode (SPE). The GO was reduced electrochemically to form reduced graphene that remarkably increases electrochemical properties owing to the intercalation of high aspect CNT on graphene flakes as shown by TEM micrograph. The surface amine functionalization of dropcasted and rGO/CNT was carried out using a bi-functional cross linker ethylenediamine. The extent of amine functionalization on modified electrodes was confirmed using energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS) and confocal microscopy. The FTIR and Raman spectra further suggested the formation of JM complex between amine functionalized electrodes and TNT leading to a shift in peak intensity together with peak broadening. The a-rGO/CNT nanocomposite prepared electrode surface leads to ultra-trace detection of TNT upto 0.01 ppb with good reproducibility (n = 3). The a-rGO/CNT sensing platform could be an alternate for sensitive detection of TNT explosive for various security and environmental applications.

MPBoot: fast phylogenetic maximum parsimony tree inference and bootstrap approximation.

Science.gov (United States)

Hoang, Diep Thi; Vinh, Le Sy; Flouri, Tomáš; Stamatakis, Alexandros; von Haeseler, Arndt; Minh, Bui Quang

2018-02-02

The nonparametric bootstrap is widely used to measure the branch support of phylogenetic trees. However, bootstrapping is computationally expensive and remains a bottleneck in phylogenetic analyses. Recently, an ultrafast bootstrap approximation (UFBoot) approach was proposed for maximum likelihood analyses. However, such an approach is still missing for maximum parsimony. To close this gap we present MPBoot, an adaptation and extension of UFBoot to compute branch supports under the maximum parsimony principle. MPBoot works for both uniform and non-uniform cost matrices. Our analyses on biological DNA and protein showed that under uniform cost matrices, MPBoot runs on average 4.7 (DNA) to 7 times (protein data) (range: 1.2-20.7) faster than the standard parsimony bootstrap implemented in PAUP*; but 1.6 (DNA) to 4.1 times (protein data) slower than the standard bootstrap with a fast search routine in TNT (fast-TNT). However, for non-uniform cost matrices MPBoot is 5 (DNA) to 13 times (protein data) (range:0.3-63.9) faster than fast-TNT. We note that MPBoot achieves better scores more frequently than PAUP* and fast-TNT. However, this effect is less pronounced if an intensive but slower search in TNT is invoked. Moreover, experiments on large-scale simulated data show that while both PAUP* and TNT bootstrap estimates are too conservative, MPBoot bootstrap estimates appear more unbiased. MPBoot provides an efficient alternative to the standard maximum parsimony bootstrap procedure. It shows favorable performance in terms of run time, the capability of finding a maximum parsimony tree, and high bootstrap accuracy on simulated as well as empirical data sets. MPBoot is easy-to-use, open-source and available at http://www.cibiv.at/software/mpboot .

Room-temperature phosphorescence chemosensor and Rayleigh scattering chemodosimeter dual-recognition probe for 2,4,6-trinitrotoluene based on manganese-doped ZnS quantum dots.

Science.gov (United States)

Zou, Wen-Sheng; Sheng, Dong; Ge, Xin; Qiao, Jun-Qin; Lian, Hong-Zhen

2011-01-01

Rayleigh scattering (RS) as an interference factor to detection sensitivity in ordinary fluorescence spectrometry is always avoided in spite of considerable efforts toward the development of RS-based resonance Rayleigh scattering (RRS) and hyper-Rayleigh scattering (HRS) techniques. Here, combining advantages of quantum dots (QDs) including chemical modification of functional groups and the installation of recognition receptors at their surfaces with those of phosphorescence such as the avoidance of autofluorescence and scattering light, l-cys-capped Mn-doped ZnS QDs have been synthesized and used for room-temperature phosphorescence (RTP) to sense and for RS chemodosimetry to image ultratrace 2,4,6-trinitrotoluene (TNT) in water. The l-cys-capped Mn-doped ZnS QDs interdots aggregate with TNT species induced by the formation of Meisenheimer complexes (MHCs) through acid-base pairing interaction between l-cys and TNT, hydrogen bonding, and electrostatic interaction between l-cys intermolecules. Although the resultant MHCs may quench the fluorescence at 430 nm, interdots aggregation can greatly influence the light scattering property of the aqueous QDs system, and therefore, dominant RS enhancement at defect-related emission wavelength was observed under the excitation of violet light of Mn-doped ZnS QDs, which was applied in chemodosimetry to image TNT in water. Meanwhile, Mn-doped ZnS QDs also exhibited a highly selective response to the quenching of the (4)T(1)-(6)A(1) transition emission (RTP) and showed a very good linearity in the range of 0.0025-0.45 μM TNT with detection limit down to 0.8 nM and RSD of 2.3% (n = 5). The proposed methods are well-suited for detecting the ultratrace TNT and distinguishing different nitro compounds.

Amine functionalized graphene oxide/CNT nanocomposite for ultrasensitive electrochemical detection of trinitrotoluene

International Nuclear Information System (INIS)

Sablok, Kavita; Bhalla, Vijayender; Sharma, Priyanka; Kaushal, Roohi; Chaudhary, Shilpa; Suri, C. Raman

2013-01-01

Highlights: ► Binding of electron-deficient trinitrotoluene to the electron rich amino groups to form JM complexes. ► rGO/CNT based platform for enhanced electrochemical detection. ► Functionalization and characterization of rGO/CNT with amine derivative. ► Ultrasenstitive and specific detection of TNT. -- Abstract: Binding of electron-deficient trinitrotoluene (TNT) to the electron rich amine groups on a substrate form specific charge-transfer Jackson–Meisenheimer (JM) complex. In the present work, we report formation of specific JM complex on amine functionalized reduced graphene oxide/carbon nanotubes- (a-rGO/CNT) nanocomposite leading to sensitive detection of TNT. The CNT were dispersed using graphene oxide that provides excellent dispersion by attaching to CNT through its hydrophobic domains and solubilizes through the available -OH and -COOH groups on screen printed electrode (SPE). The GO was reduced electrochemically to form reduced graphene that remarkably increases electrochemical properties owing to the intercalation of high aspect CNT on graphene flakes as shown by TEM micrograph. The surface amine functionalization of dropcasted and rGO/CNT was carried out using a bi-functional cross linker ethylenediamine. The extent of amine functionalization on modified electrodes was confirmed using energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS) and confocal microscopy. The FTIR and Raman spectra further suggested the formation of JM complex between amine functionalized electrodes and TNT leading to a shift in peak intensity together with peak broadening. The a-rGO/CNT nanocomposite prepared electrode surface leads to ultra-trace detection of TNT upto 0.01 ppb with good reproducibility (n = 3). The a-rGO/CNT sensing platform could be an alternate for sensitive detection of TNT explosive for various security and environmental applications

Comparative study of structure formation and mechanical behavior of age-hardened Ti–Nb–Zr and Ti–Nb–Ta shape memory alloys

Energy Technology Data Exchange (ETDEWEB)

Inaekyan, K. [Ecole de Technologie Superieure, 1100, Notre-Dame Str. West, Montreal Quebec H3C 1K3 (Canada); Brailovski, V., E-mail: vladimir.brailovski@etsmtl.ca [Ecole de Technologie Superieure, 1100, Notre-Dame Str. West, Montreal Quebec H3C 1K3 (Canada); Prokoshkin, S. [National University of Science and Technology “MISIS”, Leninskiy prosp. 4, Moscow 119049 (Russian Federation); Pushin, V. [Institute of Metal Physics, Ural Branch of Russian Academy of Sciences, 18, S. Kovalevskoy Str., Ekaterinburg 620199 (Russian Federation); Dubinskiy, S.; Sheremetyev, V. [Ecole de Technologie Superieure, 1100, Notre-Dame Str. West, Montreal Quebec H3C 1K3 (Canada); National University of Science and Technology “MISIS”, Leninskiy prosp. 4, Moscow 119049 (Russian Federation)

2015-05-15

This work sets out to study the peculiar effects of aging treatment on the structure and mechanical behavior of cold-rolled and annealed biomedical Ti–21.8Nb–6.0Zr (TNZ) and Ti–19.7Nb–5.8Ta (TNT) (at.%) shape memory alloys by means of transmission electron microscopy, X-ray diffractometry, functional fatigue and thermomechanical testing techniques. Dissimilar effects of aging treatment on the mechanical behavior of Zr- and Ta-doped alloys are explained by the differences in the ω-phase formation rate, precipitate size, fraction and distribution, and by their effect on the alloys' critical stresses and transformation temperatures. Even short-time aging of the TNZ alloy leads to its drastic embrittlement caused by “overaging”. On the contrary, during aging of the TNT alloy, formation of finely dispersed ω-phase precipitates is gradual and controllable, which makes it possible to finely adjust the TNT alloy functional properties using precipitation hardening mechanisms. To create in this alloy nanosubgrained dislocation substructure containing highly-dispersed coherent nanosized ω-phase precipitates, the following optimum thermomechanical treatment is recommended: cold rolling (true strain 0.37), followed by post-deformation annealing (600 °C, 15–30 min) and age-hardening (300 °C, 30 min) thermal treatments. It is shown that in TNT alloy, pre-transition diffraction effects (diffuse reflections) can “mask” the β-phase substructure and morphology of secondary phases. - Highlights: • TNZ alloy is characterized by much higher ω-phase precipitation rate than TNT alloy. • Difference in precipitation rates is linked to the difference in Zr and Ta diffusion mobility. • Aging of nanosubgrained TNZ alloy worsens its properties irrespective of the aging time. • Aging time of nanosubgrained TNT alloy can be optimized to improve its properties.

Technetium-99m labelled fluconazole and antimicrobial peptides for imaging of Candida albicans and Aspergillus fumigatus infections

Energy Technology Data Exchange (ETDEWEB)

Lupetti, Antonella [Department of Infectious Diseases, Leiden University Medical Center (LUMC), Leiden (Netherlands); Dipartimento di Patologia Sperimentale, Biotecnologie Mediche, Univ. di Pisa (Italy); Welling, Mick M. [Department of Radiology, Division of Nuclear Medicine, LUMC, Leiden (Netherlands); Mazzi, Ulderico [Dipartimento di Scienze Farmaceutiche, Universita degli Studi di Padova (Italy); Nibbering, Peter H. [Department of Infectious Diseases, Leiden University Medical Center (LUMC), Leiden (Netherlands); Pauwels, Ernest K.J. [Department of Radiology, Division of Nuclear Medicine, LUMC, Leiden (Netherlands); Department of Radiology, Leiden University Medical Center (LUMC) (Netherlands)

2002-05-01

The aim of this study was to investigate whether technetium-99m labelled fluconazole can distinguish fungal from bacterial infections. Fluconazole was labelled with {sup 99m}Tc and radiochemical analysis showed less than 5% impurities. The labelling solution was injected into animals with experimental infections. For comparison, we used two peptides for infection detection, i.e. UBI 29-41 and hLF 1-11, and human IgG, all labelled with {sup 99m}Tc. Mice were infected with Candida albicans or injected with heat-killed C. albicans or lipopolysaccharides to induce sterile inflammation. Also, mice were infected with Staphylococcus aureus or Klebsiella pneumoniae. Next, accumulation of {sup 99m}Tc-fluconazole and {sup 99m}Tc-labelled peptides/IgG at affected sites was determined scintigraphically. {sup 99m}Tc-fluconazole detected C. albicans infections (T/NT ratio=3.6{+-}0.47) without visualising bacterial infections (T/NT ratio=1.3{+-}0.04) or sterile inflammatory processes (heat-killed C. albicans: T/NT ratio=1.3{+-}0.2; lipopolysaccharide: T/NT ratio=1.4{+-}0.1). C. albicans infections were already seen within the first hour after injection of {sup 99m}Tc-fluconazole (T/NT ratio=3.1{+-}0.2). A good correlation (R{sup 2}=0.864; P<0.05) between T/NT ratios for this tracer and the number of viable C. albicans was found. Although {sup 99m}Tc-UBI 29-41 and {sup 99m}Tc-hLF 1-11 were able to distinguish C. albicans infections from sterile inflammatory processes in mice, these {sup 99m}Tc-labelled peptides did not distinguish these fungal infections from bacterial infections. It is concluded that {sup 99m}Tc-fluconazole distinguishes infections with C. albicans from bacterial infections and sterile inflammations. (orig.)

Role of NADPH-insensitive nitroreductase gene to metronidazole resistance of Helicobacter pylori strains

Directory of Open Access Journals (Sweden)

M Kargar

2010-06-01

Full Text Available Background and the purpose of the study: Current anti-H. pylori therapies are based on the use of two antibiotics with a proton pump inhibitor and/or a bismuth component. Metronidazole is a key component of such combination therapies in Iran. The aim of this study was to determine the role of rdxA gene in resistant strains of H. pylori isolated from Shahrekord Hajar hospital to metronidazole. Methods: This study was a cross-sectional method, which was carried out on 263 patients who referred to endoscopy department of Hajar hospital, in 2007. Biopsy samples were cultured on selective Brucella agar containing 10% blood and incubated under microerophilic condition at 370C for 3 - 7 days. Suspected colonies were tested by Gram staining, urease, oxidase and catalase activities. Organisms were confirmed to be H. pylori on the basis of the presence of ureC(glmM gene by PCR .Specific primers were used for detection of rdxA gene mutation . Results: Eighty and four strains of H. pylori determined by PCR method. Of the isolated strains, 49 (58.33% were resistant, 7 (8.33% were semi-sensitive to metronidazole and 200bp deletion in rdxA gene was observed in 2 strains. Conclusion: Because of the high metronidazole resistance in patients under study it was necessary to replace it by other antibiotics in therapeutic regimens. On the basis of low frequency of resistance mutation in rdxA gene, sequence analysis for identification of other mechanisms is suggested.

Molecular and immunohistochemical analyses of cardiac troponin T during cardiac development in the Mexican axolotl, Ambystoma mexicanum.

Science.gov (United States)

Zhang, C; Pietras, K M; Sferrazza, G F; Jia, P; Athauda, G; Rueda-de-Leon, E; Rveda-de-Leon, E; Maier, J A; Dube, D K; Lemanski, S L; Lemanski, L F

2007-01-01

The Mexican axolotl, Ambystoma mexicanum, is an excellent animal model for studying heart development because it carries a naturally occurring recessive genetic mutation, designated gene c, for cardiac nonfunction. The double recessive mutants (c/c) fail to form organized myofibrils in the cardiac myoblasts resulting in hearts that fail to beat. Tropomyosin expression patterns have been studied in detail and show dramatically decreased expression in the hearts of homozygous mutant embryos. Because of the direct interaction between tropomyosin and troponin T (TnT), and the crucial functions of TnT in the regulation of striated muscle contraction, we have expanded our studies on this animal model to characterize the expression of the TnT gene in cardiac muscle throughout normal axolotl development as well as in mutant axolotls. In addition, we have succeeded in cloning the full-length cardiac troponin T (cTnT) cDNA from axolotl hearts. Confocal microscopy has shown a substantial, but reduced, expression of TnT protein in the mutant hearts when compared to normal during embryonic development. 2006 Wiley-Liss, Inc.

N-terminal pro-brain natriuretic peptide and high-sensitivity troponin T exhibit additive prognostic value for the outcome of critically ill patients.

Science.gov (United States)

Lenz, Max; Krychtiuk, Konstantin A; Goliasch, Georg; Distelmaier, Klaus; Wojta, Johann; Heinz, Gottfried; Speidl, Walter S

2018-04-01

Patients treated at medical intensive care units suffer from various pathologies and often present with elevated troponin T (TnT) and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels. Both markers may reflect different forms of cardiac involvement in critical illness. Therefore, the aim of our study was to examine the synergistic prognostic potential of NT-proBNP and high-sensitivity TnT (hs)TnT in unselected critically ill patients. We included all consecutive patients admitted to our intensive care unit within one year, excluding those suffering from acute myocardial infarction or undergoing cardiac surgery and measured NT-proBNP and TnT plasma levels on the day of admission and 72 hours thereafter. Of the included 148 patients, 52% were male, mean age was of 64.2 ± 16.8 years and 30-day mortality was 33.2%. Non-survivors showed significantly higher NT-proBNP and TnT plasma levels as compared with survivors ( pvalue. This might be attributed to a difference in underlying pathomechanisms and an assessment of synergistic risk factors.

Chemical warfare agents identification by thermal neutron detection

International Nuclear Information System (INIS)

Liu Boxue; Ai Xianyun; Tan Daoyuan; Zhang Dianqin

2000-01-01

The hydrogen concentration determination by thermal neutron detection is a non-destructive, fast and effective method to identify chemical warfare agents and TNT that contain different hydrogen fraction. When an isotropic neutron source is used to irradiate chemical ammunition, hydrogen atoms of the agent inside shell act as a moderator and slow down neutrons. The number of induced thermal neutrons depends mainly upon hydrogen content of the agent. Therefore measurement of thermal neutron influence can be used to determine hydrogen atom concentration, thereby to determine the chemical warfare agents. Under a certain geometry three calibration curves of count rate against hydrogen concentration were measured. According to the calibration curves, response of a chemical agent or TNT could be calculated. Differences of count rate among chemical agents and TNT for each kind of shells is greater than five times of standard deviations of count rate for any agent, so chemical agents or TNT could be identified correctly. Meanwhile, blast tube or liquid level of chemical warfare agent could affect the response of thermal neutron count rate, and thereby the result of identification. (author)

Macrophage conditioned medium induced cellular network formation in MCF-7 cells through enhanced tunneling nanotube formation and tunneling nanotube mediated release of viable cytoplasmic fragments

International Nuclear Information System (INIS)

Patheja, Pooja; Sahu, Khageswar

2017-01-01

Infiltrating macrophages in tumor microenvironment, through their secreted cytokines and growth factors, regulate several processes of cancer progression such as cancer cell survival, proliferation, invasion, metastasis and angiogenesis. Recently, intercellular cytoplasmic bridges between cancer cells referred as tunneling nanotubes (TNTs) have been recognized as novel mode of intercellular communication between cancer cells. In this study, we investigated the effect of inflammatory mediators present in conditioned medium derived from macrophages on the formation of TNTs in breast adenocarcinoma cells MCF-7. Results show that treatment with macrophage conditioned medium (MφCM) not only enhanced TNT formation between cells but also stimulated the release of independently migrating viable cytoplasmic fragments, referred to as microplasts, from MCF-7 cells. Time lapse microscopy revealed that microplasts were released from parent cancer cells in extracellular space through formation of TNT-like structures. Mitochondria, vesicles and cytoplasm could be transferred from parent cell body to microplasts through connecting TNTs. The microplasts could also be resorbed into the parent cell body by retraction of the connecting TNTs. Microplast formation inhibited in presence cell migration inhibitor, cytochalasin-B. Notably by utilizing migratory machinery within microplasts, distantly located MCF-7 cells formed several TNT based intercellular connections, leading to formation of physically connected network of cells. Together, these results demonstrate novel role of TNTs in microplast formation, novel modes of TNT formation mediated by microplasts and stimulatory effect of MφCM on cellular network formation in MCF-7 cells mediated through enhanced TNT and microplast formation.

The preparation, surface structure, zeta potential, surface charge density and photocatalytic activity of TiO2 nanostructures of different shapes

International Nuclear Information System (INIS)

Grover, Inderpreet Singh; Singh, Satnam; Pal, Bonamali

2013-01-01

Titania based nanocatalysts such as sodium titanates of different morphology having superior surface properties are getting wide importance in photocatalysis research. Despite having sodium (Na) contents and its high temperature synthesis (that generally deteriorate the photoreactivity), these Na-titanates often exhibit better photoactivity than P25-TiO 2 catalyst. Hence, this work demonstrated the influence of crystal structure, BET surface area, surface charge, zeta potential (ζ) and metal loading on the photocatalytic activity of as-prepared sodium titanate nanotube (TNT) and titania nanorod (TNR). Straw like hollow orthorhombic-TNT (Na 2 Ti 2 O 5 ·H 2 O) particles (W = 9–12 nm and L = 82–115 nm) and rice like pure anatase-TNR particles (W = 8–13 nm and L = 81–134 nm) are obtained by the hydrothermal treatment of P25-TiO 2 with NaOH, which in fact, altered the net surface charge of TNT and TNR particles. The observed ζ = −2.82 (P25-TiO 2 ), −13.5 (TNT) and −22.5 mV (TNR) are significantly altered by the Ag and Cu deposition. It has been found here that TNT displayed best photocatalytic activity for the imidacloprid insecticide (C 9 H 10 ClN 5 O 2 ) degradation to CO 2 formation under UV irradiation because of its largest surface area 176 m 2 g −1 among the catalysts studied.

Macrophage conditioned medium induced cellular network formation in MCF-7 cells through enhanced tunneling nanotube formation and tunneling nanotube mediated release of viable cytoplasmic fragments

Energy Technology Data Exchange (ETDEWEB)

Patheja, Pooja, E-mail: pooja.patheja8@gmail.com [Laser Biomedical Applications Section, Raja Ramanna Centre for Advanced Technology, Indore 452013, Madhya Pradesh (India); Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, Maharashtra (India); Sahu, Khageswar [Laser Biomedical Applications Section, Raja Ramanna Centre for Advanced Technology, Indore 452013, Madhya Pradesh (India)

2017-06-15

Infiltrating macrophages in tumor microenvironment, through their secreted cytokines and growth factors, regulate several processes of cancer progression such as cancer cell survival, proliferation, invasion, metastasis and angiogenesis. Recently, intercellular cytoplasmic bridges between cancer cells referred as tunneling nanotubes (TNTs) have been recognized as novel mode of intercellular communication between cancer cells. In this study, we investigated the effect of inflammatory mediators present in conditioned medium derived from macrophages on the formation of TNTs in breast adenocarcinoma cells MCF-7. Results show that treatment with macrophage conditioned medium (MφCM) not only enhanced TNT formation between cells but also stimulated the release of independently migrating viable cytoplasmic fragments, referred to as microplasts, from MCF-7 cells. Time lapse microscopy revealed that microplasts were released from parent cancer cells in extracellular space through formation of TNT-like structures. Mitochondria, vesicles and cytoplasm could be transferred from parent cell body to microplasts through connecting TNTs. The microplasts could also be resorbed into the parent cell body by retraction of the connecting TNTs. Microplast formation inhibited in presence cell migration inhibitor, cytochalasin-B. Notably by utilizing migratory machinery within microplasts, distantly located MCF-7 cells formed several TNT based intercellular connections, leading to formation of physically connected network of cells. Together, these results demonstrate novel role of TNTs in microplast formation, novel modes of TNT formation mediated by microplasts and stimulatory effect of MφCM on cellular network formation in MCF-7 cells mediated through enhanced TNT and microplast formation.

Preparation, characterization and visible-light-driven photocatalytic activity of a novel Fe(III) porphyrin-sensitized TiO{sub 2} nanotube photocatalyst

Energy Technology Data Exchange (ETDEWEB)

Wei, Meng [National Engineering Lab of Textile Fiber Materials & Processing Technology, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Wan, Junmin, E-mail: wwjm2001@126.com [National Engineering Lab of Textile Fiber Materials & Processing Technology, Zhejiang Sci-Tech University, Hangzhou 310018 (China); State Key Laboratory of advanced Textiles Materials and Manufacture Technology, MOE, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Hu, Zhiwen; Peng, Zhiqin; Wang, Bing [National Engineering Lab of Textile Fiber Materials & Processing Technology, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Wang, Huigang [State Key Laboratory of advanced Textiles Materials and Manufacture Technology, MOE, Zhejiang Sci-Tech University, Hangzhou 310018 (China)

2017-01-01

Highlights: • FeTCPP-TNT photocatalysts are synthesized. • FeTCPP and tube-like structure are helpful to induce interfacial charge transfer at surface junction. • FeTCPP and tube-like structure are favorable for enhancing photocatalytic activity. • The photocatalytic mechanism of FeTCPP-TNT is proposed. • The photocatalyst are proven to be effective and chemically-stable catalysts. - Abstract: Iron(III) meso-tetra(4-carboxyphenyl) porphyrin (FeTCPP) loaded on the surface of TiO{sub 2} nanotubes (TNTs) has been successfully prepared through improved hydrothermal and heating reflux process. The new photocatalyst has been characterized and analyzed by TEM/EDS, BET, XRD, FT-IR, DRS, PL, XPS and EPR. The photocatalytic activity of FeTCPP/TNT nanocomposite was evaluated by the photodegradation of MB under visible light irradiation. The degradation results showed a purification of more than 90% MB in simulating wastewater, and confirmed that the prepared FeTCPP/TNT nanocomposite has acquired superior photocatalytic activitiy. The 6 times cycled results suggested the great stability of the photocatalyst. These results confirmed the FeTCPP played an important role in capturing photons and expanding the absorption wavelength to the visible light region, and the FeTCPP/TNT photocatalyst is also beneficial for the electron transfer and long-distance transmission, and could efficiently increase the separation of the electron-hole pairs, and accelerate the decomposition of organic pollutants. In addition, nano-sized structures can increase adsorption capability.

Clinical value of 18F-FDG coincidence imaging for diagnosis of nasopharyngeal carcinoma

International Nuclear Information System (INIS)

Ning Yanli; Lou Cen; Huang Zhongke; Shi Guohua; Chen Dongfang; Mu Da

2012-01-01

Objective: To investigate the value of 18 F-FDG coincidence imaging for diagnosis of nasopharyngeal carcinoma. Methods: A total of 45 patients with nasopharyngeal carcinoma (33 males and 12 females, average age (55.56 ± 13.50) years), who underwent 18 F-FDG coincidence imaging before treatment, were studied retrospectively. The images of 18 F-FDG coincidence imaging (GE Millennium VG SPECT) and MRI were analyzed. The radioactivity ratio of the accumulated regions to cerebellum (T/NT)was calculated by ROI technique. The volume of nasopharyngeal carcinoma was recorded by MRI. The positive rates of 18 F-FDG coincidence imaging and EB virus-related antibody measurements were compared by paired χ 2 test. The correlation between T/NT ratios and tumor volumes were tested by Pearson correlation, and then ROC curves were established. The T/NT ratios and tumor volumes of different groups (different first symptoms, clinical stages, T stages, pathological classification and outcomes, with or without lymph node enlargement) were compared by t-test and rank sum test. Results: The positive rate of 18 F-FDG coincidence imaging was 97.78% (44/45), and the positive rate of EB virus-related antibody measurement was 95.56% (43/45, χ 2 =1.33, P>0.05). The T/NT ratio (2.439 ±1.119) and tumor volume ((7.311 ± 8.280) cm 3 ) of primary lesions had a positive correlation (r=0.463, P<0.05). The cut-off values of T/NT ratio and the tumor volume were 2.396 and 7.348 cm 3 , respectively, by ROC curves. T/NT ratios in groups with or without first symptom of epistaxis (2.847 ± 1.254 vs 2.082 ± 0.863, t=-2.409) and groups with or without facial numbness (2.855 ± 1.261 vs 2.134 ± 0.913, t=-2.225) were both significantly different (both P<0.05). T/NT ratios of differentiated and undifferentiated cancer were 2.266 ± 0.997 and 2.971 ± 1.351, respectively (t=-2.018, P<0.05). There was a significant difference of tumor volumes between groups with or without facial numbness (t=-2.684, P<0

Integrated Data Collection Analysis (IDCA) Program — KClO₃ (as received)/Icing Sugar

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Sorenson, Daniel N. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Shelley, Timothy J. [Air Force Research Lab. (AFRL/RXQL), Tyndall AFB, FL (United States); Reyes, Jose A. [Applied Research Associates, Inc., Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whipple, Richard E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2011-05-23

The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small-Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of a mixture of KClO₃ as received from the manufacturer mixed with icing sugar, sized through a 100-mesh sieve—KClO₃/icing sugar (AR) mixture. This material was selected because of the challenge of performing SSST testing of a mixture of two solid materials. The mixture was found to: 1) be more sensitive to impact than RDX, similar to PETN, 2) be the same or less sensitive to friction than PETN, and 3) to be less sensitive to spark than RDX. The thermal analysis showed that the mixture has thermally stability similar to RDX and is perhaps more energetic upon decomposition but variable results indicate sampling issues. Compared to the 100-mesh sieved counter part, the KClO₃/icing sugar (-100) mixture, the AR mixture was found to be about the same sensitivity towards impact, friction and ESD.

Gaseous byproducts from high-temperature thermal conversion elemental analysis of nitrogen- and sulfur-bearing compounds with considerations for δ2H and δ18O analyses.

Science.gov (United States)

Hunsinger, Glendon B; Tipple, Christopher A; Stern, Libby A

2013-07-30

High-temperature, conversion-reduction (HTC) systems convert hydrogen and oxygen in materials into H2 and CO for δ(2)H and δ(18)O measurements by isotope ratio mass spectrometry. HTC of nitrogen- and sulfur-bearing materials produces unintended byproduct gases that could affect isotope analyses by: (1) allowing isotope exchange reactions downstream of the HTC reactor, (2) creating isobaric or co-elution interferences, and (3) causing deterioration of the chromatography. This study characterizes these HTC byproducts. A HTC system (ThermoFinnigan TC/EA) was directly connected to a gas chromatograph/quadrupole mass spectrometer in scan mode (m/z 8 to 88) to identify the volatile products generated by HTC at conversion temperatures of 1350 °C and 1450 °C for a range of nitrogen- and sulfur-bearing solids [keratin powder, horse hair, caffeine, ammonium nitrate, potassium nitrate, ammonium sulfate, urea, and three nitrated organic explosives (PETN, RDX, and TNT)]. The prominent HTC byproduct gases include carbon dioxide, hydrogen cyanide, methane, acetylene, and water for all nitrogen-bearing compounds, as well as carbon disulfide, carbonyl sulfide, and hydrogen sulfide for sulfur-bearing compounds. The 1450 °C reactor temperature reduced the abundance of most byproduct gases, but increased the significant byproduct, hydrogen cyanide. Inclusion of a post-reactor chemical trap containing Ascarite II and Sicapent, in series, eliminated the majority of byproducts. This study identified numerous gaseous HTC byproducts. The potential adverse effects of these gases on isotope ratio analyses are unknown but may be mitigated by higher HTC reactor temperatures and purifying the products with a purge-and-trap system or with chemical traps. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.

Use of dilute ammonia gas for treatment of 1,2,3-trichloropropane and explosives-contaminated soils.

Science.gov (United States)

Coyle, Charles G; Waisner, Scott A; Medina, Victor F; Griggs, Chris S

2017-12-15

Laboratory studies were performed to test a novel reactive gas process for in-situ treatment of soils containing halogenated propanes or explosives. A soil column study, using a 5% ammonia-in-air mixture, established that the treatment process can increase soil pH from 7.5 to 10.2. Batch reactor experiments were performed to demonstrate contaminant destruction in sealed jars exposed to ammonia. Comparison of results from batch reactors that were, and were not, exposed to ammonia demonstrated reductions in concentrations of 1,2,3-trichloropropane (TCP), 1,3-dichloropropane (1,3-DCP), 1,2-dicholoropropane (1,2-DCP) and dibromochloropropane (DBCP) that ranged from 34 to 94%. Decreases in TCP concentrations at 23° C ranged from 37 to 65%, versus 89-94% at 62° C. A spiked soil column study was also performed using the same set of contaminants. The study showed a pH penetration distance of 30 cm in a 2.5 cm diameter soil column (with a pH increase from 8 to > 10), due to treatment via 5% ammonia gas at 1 standard cubic centimeter per minute (sccm) for 7 days. Batch reactor tests using explosives contaminated soils exhibited a 97% decrease in 2,4,6-trinitrotoluene (TNT), an 83% decrease in nitrobenzene, and a 6% decrease in hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). A biotransformation study was also performed to investigate whether growth of ammonia-oxidizing microorganisms could be stimulated via prolonged exposure of soil to ammonia. Over the course of the 283 day study, only a very small amount of nitrite generation was observed; indicating very limited ammonia monooxygenase activity. Overall, the data indicate that ammonia gas addition can be a viable approach for treating halogenated propanes and some types of explosives in soils. Published by Elsevier Ltd.

Integrated Data Collection Analysis (IDCA) Program — Bullseye^® Smokeless Powder

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorensen, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Phillips, Jason J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Shelley, Timothy J. [Bureau of Alcohol, Tobacco and Firearms, Redstone Arsenal, AL (United States); Reyes, Jose A. [Applied Research Associates, Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2013-05-30

The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small- Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of Bullseye^® smokeless powder (Gunpowder). The participants found the Gunpowder: 1) to have a range of sensitivity to impact, from less than RDX to almost as sensitive as PETN, 2) to be moderately sensitive to BAM and ABL friction, 3) have a range for ESD, from insensitive to more sensitive than PETN, and 4) to have thermal sensitivity about the same as PETN and RDX.

The preparation, surface structure, zeta potential, surface charge density and photocatalytic activity of TiO{sub 2} nanostructures of different shapes

Energy Technology Data Exchange (ETDEWEB)

Grover, Inderpreet Singh; Singh, Satnam; Pal, Bonamali, E-mail: bpal@thapar.edu

2013-09-01

Titania based nanocatalysts such as sodium titanates of different morphology having superior surface properties are getting wide importance in photocatalysis research. Despite having sodium (Na) contents and its high temperature synthesis (that generally deteriorate the photoreactivity), these Na-titanates often exhibit better photoactivity than P25-TiO{sub 2} catalyst. Hence, this work demonstrated the influence of crystal structure, BET surface area, surface charge, zeta potential (ζ) and metal loading on the photocatalytic activity of as-prepared sodium titanate nanotube (TNT) and titania nanorod (TNR). Straw like hollow orthorhombic-TNT (Na{sub 2}Ti{sub 2}O{sub 5}·H{sub 2}O) particles (W = 9–12 nm and L = 82–115 nm) and rice like pure anatase-TNR particles (W = 8–13 nm and L = 81–134 nm) are obtained by the hydrothermal treatment of P25-TiO{sub 2} with NaOH, which in fact, altered the net surface charge of TNT and TNR particles. The observed ζ = −2.82 (P25-TiO{sub 2}), −13.5 (TNT) and −22.5 mV (TNR) are significantly altered by the Ag and Cu deposition. It has been found here that TNT displayed best photocatalytic activity for the imidacloprid insecticide (C{sub 9}H{sub 10}ClN{sub 5}O{sub 2}) degradation to CO{sub 2} formation under UV irradiation because of its largest surface area 176 m{sup 2} g{sup −1} among the catalysts studied.

Macrophage conditioned medium induced cellular network formation in MCF-7 cells through enhanced tunneling nanotube formation and tunneling nanotube mediated release of viable cytoplasmic fragments.

Science.gov (United States)

Patheja, Pooja; Sahu, Khageswar

2017-06-15

Infiltrating macrophages in tumor microenvironment, through their secreted cytokines and growth factors, regulate several processes of cancer progression such as cancer cell survival, proliferation, invasion, metastasis and angiogenesis. Recently, intercellular cytoplasmic bridges between cancer cells referred as tunneling nanotubes (TNTs) have been recognized as novel mode of intercellular communication between cancer cells. In this study, we investigated the effect of inflammatory mediators present in conditioned medium derived from macrophages on the formation of TNTs in breast adenocarcinoma cells MCF-7. Results show that treatment with macrophage conditioned medium (MɸCM) not only enhanced TNT formation between cells but also stimulated the release of independently migrating viable cytoplasmic fragments, referred to as microplasts, from MCF-7 cells. Time lapse microscopy revealed that microplasts were released from parent cancer cells in extracellular space through formation of TNT-like structures. Mitochondria, vesicles and cytoplasm could be transferred from parent cell body to microplasts through connecting TNTs. The microplasts could also be resorbed into the parent cell body by retraction of the connecting TNTs. Microplast formation inhibited in presence cell migration inhibitor, cytochalasin-B. Notably by utilizing migratory machinery within microplasts, distantly located MCF-7 cells formed several TNT based intercellular connections, leading to formation of physically connected network of cells. Together, these results demonstrate novel role of TNTs in microplast formation, novel modes of TNT formation mediated by microplasts and stimulatory effect of MɸCM on cellular network formation in MCF-7 cells mediated through enhanced TNT and microplast formation. Copyright © 2017 Elsevier Inc. All rights reserved.

Enhanced photoactivity of graphene/titanium dioxide nanotubes for removal of Acetaminophen

International Nuclear Information System (INIS)

Tao, Hong; Liang, Xiao; Zhang, Qian; Chang, Chang-Tang

2015-01-01

Highlights: • TiO 2 and graphite oxide were used as precursors of titanium dioxide nanotubes and graphene respectively. Titanium dioxide nanotube and graphene (GR-TNT) nanocomposites were synthesized through a simple hydrothermal method. • And its application to removal acetaminophen, degradation efficiency is more than 96%. • The photocatalytic degradation results indicated that the sample with 5% GO in GR-TNT nanocomposites for 3 h had the highest degradation rate. • The degradation intermediates of acetaminophen by the composites were invested by GC-MS and the possible pathways were invested. - Abstract: Acetaminophen is commonly used as an antipyretic or analgesics agent and poses threat to human health. In this research, TiO 2 and graphite oxide were used as precursors of titanium dioxide nanotubes and graphene respectively. Titanium dioxide nanotube and graphene (GR-TNT) nanocomposites were synthesized through a hydrothermal method. FT-IR, UV-Vis, XRD, and TGA were used to characterize the catalysts. The acetaminophen degradation rate can reach up to 96% under UV light irradiation for 3 h and with the 5% GR-TNT dosage of 0.1 g L −1 . Further experiments were done to probe the mechanism of the photocatalytic reaction catalyzed by the GR-TNT composite. EDTA (hole scavengers) and t-BuOH (radical scavengers) were used to detect the main active oxidative species in the system. The results showed that the holes are the main oxidation species in the photocatalytic process. This study provides a new prospect for acetaminophen degradation by using high efficiency catalysts

The controlled release of simvastatin from TiO{sub 2} nanotubes to promote osteoblast differentiation and inhibit osteoclast resorption

Energy Technology Data Exchange (ETDEWEB)

Lai, Min, E-mail: minlai@jsnu.edu.cn [School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu 221116 (China); Jin, Ziyang; Yang, Xinyi; Wang, Huaying [School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu 221116 (China); Xu, Kui [Biomedical Engineering Center, School of Medicine, Ningbo University, Ningbo, Zhejiang 315211 (China)

2017-02-28

Highlights: • The TiO{sub 2} nanotube substrates filled with simvastatin were successfully coated using chitosan/gelatin multilayers. • The bio-functionalized substrates display controlled release of simvastatin in a sustained manner. • The bio-functionalized substrates have great potential for improving osteoblast differentiation. • The bio-functionalized substrates effectively inhibit osteoclast differentiation. - Abstract: The aim of this study was to fabricate a novel drug-releasing bioactive platform that has excellent potential for improving osteoblast differentiation and inhibiting osteoclast resorption. TiO{sub 2} nanotubes (TNTs) with an outer diameter of around 70 nm were prepared by an anodization method. TNTs were filled with simvastatin (SV) and then coated using chitosan/gelatin multilayers (TNT-SV-LBL). The successful fabrication of TNT-SV-LBL substrates was confirmed by field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and contact angle measurement, respectively. The in vitro release behavior of simvastatin from TNT-SV-LBL substrates showed a sustained release as compared to the uncoated group. Osteoblasts adhering to TNT-SV-LBL substrates attached well and displayed significantly higher (p < 0.01) cell viability compared with the other substrates. More importantly, osteoblasts grown on TNT-SV-LBL substrates displayed a statistically significant (p < 0.01 or p < 0.05) increase in protein production levels of alkaline phosphatase (ALP), osteocalcin (OC) and mRNA expression of runt related transcription factor 2 (Runx2), ALP, collagen type I (Col I), osteopontin (OPN), OC and osteoprotegerin (OPG) compared to the other groups after 4, 7 and 14 days of culture, respectively. Additionally, multinuclear osteoclastic differentiation of RAW264.7 cells grown on TNT-SV-LBL substrates was inhibited as confirmed by tartrate-resistant acid phosphatase (TRAP) analysis. These