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High Explosive Crater Studies: Tuff

Description: Abstract: "Spherical charges of TNT, each weighing 256 pounds, were exploded at various depths in tuff to determine apparent crater dimensions in a soft rock. No craters were obtained for depths of burst equal to or greater than 13.3 feet. It was deduced that rock fragments were sufficiently large that charges of greater magnitude should be employed for crater experiments intended as models of nuclear explosions."
Date: April 1961
Creator: Murphey, Byron F.
Partner: UNT Libraries Government Documents Department

Solid phase microextraction of amino-dinitrotoluenes in tissue.

Description: TNT (2,4,6-trinitrotoluene) readily and predominantly transforms to 2ADNT (2-amino-4,6-dinitrotoluene) and 4ADNT (4-amino-2,6-dinitrotoluene) in environmental matrixes and tissues. Solid phase microextraction (SPME) was used to extract ADNTs (amino-dinitrotoluenes) from tissue as a potential method to investigate the recalcitrance of metabolically-generated ADNTs versus absorbed ADNTs. Tubifex tubifex was allowed to metabolize TNT into ADNTs in 24-hr static non-renewal exposure test followed by 24-hr depuration in clean reconstituted hard water. Polyacrylate-coated (PA) SPME fibers were then deployed and agitated in tissue homogenates containing metabolically-generated ADNTs for 48 hr to provide a measure of available ADNTs. Extractability of ADNTs from T. tubifex tissue containing metabolically-generated ADNTs was significantly less than extractability of ADNTs from T. tubifex tissue containing absorbed ADNTs: 50-60% and 81-90% of expected extractability based on fiber-water partition ratio. The lower SPME extractability of metabolically-generated ADNTs may stem from the unavailability of metabolically-generated ADNTs sequestered in tissue or bound to tissue macromolecules during metabolism of TNT to ADNT. Tissue extractions using SPMEs may be able to estimate such bound organic residues in tissue and serve as potential indicators of toxicological bioavailability and biomagnification potential of tissue-associated organic compounds.
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Date: December 2004
Creator: Tsui-Bowen, Alethea
Partner: UNT Libraries

DSWA calorimeter bomb experiments

Description: Two experiments were performed in which 25 grams of TNT were detonated inside an expended detonation calorimeter bomb. The bomb had a contained volume of approximately 5.28 liters. In the first experiment, the bomb was charged with 3 atmospheres of nitrogen. In the second, it was charged with 2.58 atmospheres (23.1 psi gage) of oxygen. In each experiment pressure was monitored over a period of approximately 1200 microseconds after the pulse to the CDU. Monitoring was performed via two 10,000 psi 102AO3 PCB high frequency pressure transducers mounted symmetrically in the lid of the calorimeter bomb. Conditioners used were PCB 482As. The signals from the transducers were recorded in digital format on a multi channel Tektronix scope. The sampling frequency was 10 Mhz (10 samples per microsecond). After a period of cooling following detonation, gas samples were taken and were subsequently submitted for analysis using gas mass spectrometry. Due to a late request for post shot measurement, it was only possible to make a rough estimate of the weight of debris (carbon) remaining in the calorimeter bomb following the second experiment.
Date: October 1, 1998
Creator: Cunningham, B
Partner: UNT Libraries Government Documents Department

Effect of Weather on the Predicted PMN Landmine Chemical Signature for Kabul, Afghanistan

Description: Buried landmines are often detected through the chemical signature in the air above the soil surface by mine detection dogs. Environmental processes play a significant role in the chemical signature available for detection. Due to the shallow burial depth of landmines, the weather influences the release of chemicals from the landmine, transport through the soil to the surface, and degradation processes in the soil. The effect of weather on the landmine chemical signature from a PMN landmine was evaluated with the T2TNT code for Kabul, Afghanistan. Results for TNT and DNT gas-phase and soil solid-phase concentrations are presented as a function of time of the day and time of the year.
Date: November 1, 2002
Creator: Webb, Stephen W. & Phelan, James M.
Partner: UNT Libraries Government Documents Department

Rapid identification of causative insertions underlying Medicago truncatula Tnt1 mutants defective in symbiotic nitrogen fixation from a forward genetic screen by whole genome sequencing

Description: This article demonstrates that whole genome sequencing is an efficient approach for identification of causative genes underlying symbiotic nitrogen fixation defective phenotypes in Medicago truncatula Tnt1 insertion mutants obtained via forward genetic screens.
Date: February 27, 2016
Creator: Veerappan, Vijaykumar; Jani, Mehul; Kadel, Khem; Troiani, Taylor; Gale, Ronny; Mayes, Tyler et al.
Partner: UNT College of Arts and Sciences

Standoff ultraviolet raman scattering detection of trace levels of explosives.

Description: Ultraviolet (UV) Raman scattering with a 244-nm laser is evaluated for standoff detection of explosive compounds. The measured Raman scattering albedo is incorporated into a performance model that focused on standoff detection of trace levels of explosives. This model shows that detection at {approx}100 m would likely require tens of seconds, discouraging application at such ranges, and prohibiting search-mode detection, while leaving open the possibility of short-range point-and-stare detection. UV Raman spectra are also acquired for a number of anticipated background surfaces: tile, concrete, aluminum, cloth, and two different car paints (black and silver). While these spectra contained features in the same spectral range as those for TNT, we do not observe any spectra similar to that of TNT.
Date: October 1, 2011
Creator: Kulp, Thomas J.; Bisson, Scott E. & Reichardt, Thomas A.
Partner: UNT Libraries Government Documents Department

SPE2 Far-field Seismic Data Quicklook

Description: The purpose of this report is to provide a brief overview of the far-field seismic data collected by the array of instruments (Figures 1 and 2) deployed by the Source Physics experiment for shots 1 (roughly 100 kg TNT equivalent at a depth of 60 m) and shot 2, (roughly 2000 kg TNT equivalent at a depth of 45 m). 'Far-field' is taken to refer to instruments in the zone of purely elastic response at distances of 100 m or greater. The primary focus is data from the main instrument array and hence data from other groups is not considered. Infrasound data is not addressed nor any remote sensing data. Data processing was done at LLNL in parallel with the effort at UNR. Raw reftek data was sent via hard disk from NsTec. Reftek data was converted to SEGY and then to SAC format. Data files were renamed according to station and channel information. Reftek logs were reviewed. These data have been reviewed for consistency with the UNR data on the server. The primary goal was quality check and a summary is provided in Tables 1 and 2.
Date: February 14, 2012
Creator: Mellors, R J; Harben, P; Ford, S; Walter, W R; Hauk, T; Ruppert, S et al.
Partner: UNT Libraries Government Documents Department

TNT Prout-Tompkins Kinetics Calibration with PSUADE

Description: We used the code PSUADE to calibrate Prout-Tompkins kinetic parameters for pure recrystallized TNT. The calibration was based on ALE3D simulations of a series of One Dimensional Time to Explosion (ODTX) experiments. The resultant kinetic parameters differed from TNT data points with an average error of 28%, which is slightly higher than the value of 23% previously calculated using a two-point optimization. The methodology described here provides a basis for future calibration studies using PSUADE. The files used in the procedure are listed in the Appendix.
Date: April 11, 2007
Creator: Wemhoff, A P & Hsieh, H
Partner: UNT Libraries Government Documents Department

Quadractic Model of Thermodynamic States in SDF Explosions

Description: We study the thermodynamic states encountered during Shock-Dispersed-Fuel (SDF) explosions. Such explosions contain up to six components: three fuels (PETN, TNT and Aluminum) and their products corresponding to stoichiometric combustion with air. We establish the loci in thermodynamic state space that correctly describes the behavior of the components. Results are fit with quadratic functions that serve as fast equations of state suitable for 3D numerical simulations of SDF explosions.
Date: May 4, 2007
Creator: Kuhl, A L & Khasainov, B
Partner: UNT Libraries Government Documents Department

Cometabolic bioremediation

Description: Cometabolic bioremediation is probably the most under appreciated bioremediation strategy currently available. Cometabolism strategies stimulate only indigenous microbes with the ability to degrade the contaminant and cosubstrate e.g. methane, propane, toluene and others. This highly targeted stimulation insures that only those microbes that can degrade the contaminant are targeted, thus reducing amendment costs, well and formation plugging, etc. Cometabolic bioremediation has been used on some of the most recalcitrant contaminants, e.g. PCE, TCE, MTBE, TNT, dioxane, atrazine, etc. Methanotrophs have been demonstrated to produce methane monooxygense, an oxidase that can degrade over 300 compounds. Cometabolic bioremediation also has the advantage of being able to degrade contaminants to trace concentrations, since the biodegrader is not dependent on the contaminant for carbon or energy. Increasingly we are finding that in order to protect human health and the environment that we must remediate to lower and lower concentrations, especially for compounds like endocrine disrupters, thus cometabolism may be the best and maybe the only possibility that we have to bioremediate some contaminants.
Date: February 15, 2009
Creator: Hazen, Terry C.
Partner: UNT Libraries Government Documents Department

Depth of burial experiments at Balapan

Description: We report of a series of experiments designed to discriminate underground explosion sources at various depths by means of their seismic signatures at regional distances. This series was a joint effort of the US Department of Energy (DOE), the US Defense Special Weapons Agency (DSWA), and the National Nuclear Center of the Republic of Kazakhstan (NNC). The series consisted of three 25-ton explosions, at depths of 55 m, 300 m, and 50 m. In addition, a 5-ton checkout explosion was fired at a depth of 630 m, and small-scale explosions at each site were carried out so that the empirical Green`s functions could be derived. Broadband and short-period seismic data were recorded at an eight-station network within Kazakhstan, at nominal ranges varying from 100-1500 km, and with good azimuthal coverage for regional phases. In addition, seismic measurements were made at former NRDC sites (BAY and KKL), infrasound recordings were made at the cross array at Kurchatov, and close-in seismic measurements were also made at ranges from ground zero to 20 km. Although the main objective of this series was to study depth-of- burial (DOB) effects on the excitation of regional phases such as LG and RG, and to determine whether peaks in the coda spectral shape correlate well with DOB, a secondary objective was to help calibrate the site of the Kazakhstan seismic network, especially the primary IMS station at MAKanchi, and the auxiliary IMS stations at KURchatov and AKTyubinsk.
Date: November 1, 1997
Creator: Glenn, L.A. & Myers, S.C.
Partner: UNT Libraries Government Documents Department

Thermal properties of explosives. Quarterly report, January, February, March 1964

Description: Henkin`s test data are reported for comparisons of the following: dry-to-moist samples, PBX 9404 in brass and gold-plated blasting caps, Holston HMX with Bridgewater HMX, LX-04-1 and LX-04-1 + Ucon oil, and PETN, LX-04-1 and Extex. The time-to-explosion curves for HMX and PBX 9404 are also given. A description of the pyrolysis apparatus and the method of calibrating the sample temperature to the response of the thermal conductivity detector are reported. The pyrolytic decomposition curves of several standard explosives and six specially prepared HMX samples (LRL raw material No. A-311 through A-316) are included. A controlled atmosphere D.T.A. is described and the thermograms of PETN with an atmosphere of air at 85 psi, nitrogen at 85 psi and 200 psi are given. The thermograms indicate that PETN becomes more sensitive as the pressure increases. Chemical reactivity data are reported for Comp B, Comp B-3, Comp C-4, HMX, PBX 9011, PBX 9205, Tetryl and TNT. Also, test results are reported for LX-01-1 and Comp B-3 heated at 150{degrees}C for 22 hours, LX-02-1 heated at 100{degrees}C for 22 hours, and pressed pellets of PBX 9404 and PBX 9404 + powdered lead.
Date: September 1, 1997
Creator: Myers, L.C.
Partner: UNT Libraries Government Documents Department


Description: This report describes the Eco Logic Process and discusses the procedures and results of a pilot-scale treatability study on explosives in shell casings. The study was conducted as part of a contract which was awarded to Science Applications International Corporation (SAIC) and Eco Logic by the Department of Energy's Federal Energy Technology Center (FETC) in Morgantown, West Virginia to conduct treatability studies on complex hazardous wastes, energetic and low level mixed wastes. The U.S. Army currently decontaminates spent shell casings using a bailout or high pressure wash process that removes a large amount of the propellant from the casing but not enough to allow recycle of the entire casing intact; the U.S. Army currently projects the use of a metal parts furnace to completely decontaminate the shell casings. Use of the Eco Logic Process to decontaminate the shell casings would allow the shell casing to be reused intact. In addition to explosives commonly used by the Army such as TNT and Composition B, ARDEC personnel also were interested in the decontamination of shell casings with a residual of the propellant Yellow D which is a common energetic in artillery shell casings used by the Navy. A series of treatability tests on neat samples of explosive as well as shell casings containing each explosive were performed between June 9 and June 20, 1997 at the US Army's Edgewood Research Development, Engineering Center (ERDEC) toxic test chamber facility located at Aberdeen Proving Ground, Maryland., including a 2 gram neat sample of TNT and lO gram samples of TNT, composition B and Yellow D to determine optimal treatment conditions for each explosive followed by two tests on washed shell casings containing trace amounts of TNT and a total of six tests, two each on shell casings lined with 10 grams of TNT, composition ...
Date: June 17, 1998
Partner: UNT Libraries Government Documents Department

Bioavailability and toxicity of 2,4,6-trinitrotoluene in sediment.

Description: TNT (2,4,6-trinitrotoluene) is a persistent contaminant at many military installations and poses a threat to aquatic ecosystems. Data from environmental fate and toxicity studies with TNT revealed that sediment toxicity test procedures required modification to accurately assess sediment TNT toxicity. Key modifications included aging TNT-spiked sediments 8-14 d, basing lethal dose on measured sediment concentrations of the molar sum of TNT and its main nitroaromatic (NA) transformation products (SNA), basing sublethal dose on average sediment SNA concentrations obtained from integration of sediment SNA transformation models, avoiding overlying water exchanges, and minimizing toxicity test durations. Solid phase microextraction fibers (SPMEs) were investigated as a biomimetic chemical measure of toxicity and bioavailability. Both organism and SPME concentrations provided measures of lethal dose independent of exposure scenario (TNT-spiked sediment or TNT-spiked water) for Tubifex tubifex. Among all benthic organisms tested (Chironomus tentans, Ceriodaphnia dubia, T. tubifex) and matrixes, median lethal dose (LC50) estimates based on SPME and organism concentrations ranged from 12.6 to 55.3 mmol SNA/ml polyacrylate and 83.4 to 172.3 nmol SNA/g tissue, ww, respectively. For Tubifex, LC50s (95% CI) based on SNA concentrations in sediment and SPMEs were 223 (209-238) nmol SNA/g, dw and 27.8 (26.0-29.8) mmol SNA/ml, respectively. Reproductive effects occurred at slightly lower exposures. Median effective dose (EC50) estimates (95% CI) for Tubifex cocoon production, based on sediment and SPME concentrations, were 118 (114-122) nmol SNA/g, dw and 21.8 (21.2-22.4) mmol SNA/ml, respectively. Bioconcentration experiments with Tubifex revealed that compound hydrophobicity predicted the toxicokinetics and bioconcentration of these compounds from water, however, there was a large discrepancy between the toxicokinetics of absorbed versus metabolically-generated aminodinitrotoluenes. A large portion of bioconcentrated, radiolabeled TNT transformation products could not be identified. In addition to their ability to provide matrix-independent measures of dose, SPME concentrations were more accurate indicators of bioavailable NAs than ...
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Date: May 2004
Creator: Conder, Jason M.
Partner: UNT Libraries

Forward Genetic Characterization of Medicago truncatula Tnt1 Insertion Mutants Defective in Nodule Development and Symbiotic Nitrogen Fixation

Description: Legumes are unique plants because they form special structures “nodules”, via symbiotic relationships with rhizobial bacteria present in the soil. Once rhizobia mature inside nodules, they fix atmospheric nitrogen providing a source of bioavailable nitrogen to the plant. To discover novel genetic components involved in the legume-rhizobia symbiosis by using forward genetic screening, we have isolated Medicago truncatula Tnt1 insertion mutants in the R108 ecotype, which are defective in nodule development and symbiotic nitrogen fixation in response to Sinorhizobium meliloti. Out of three mutants NF11044, NF11217 and NF8324, one of the mutants showed brown nodules and Fix- phenotype that is defective in symbiotic nitrogen fixation. The other two mutants showed white nodules and Fix- phenotype, also indicator of defects in symbiotic nitrogen fixation. To identify the underlying mutation causing the phenotype, we have developed molecular genetic markers by obtaining genomic sequences flanking the Tnt1 insertions by TAIL-PCR and Illumina sequencing. To carry out co-segregation analysis, back-crossed BC1F2 segregating populations were obtained. These are being phenotyped, genotyped and analyzed for co-segregation of the phenotype with the Tnt1 genetic markers. Back-crossing also has the effect of reducing the Tnt1 insertions, which are not linked to the nodulation defective phenotypes. Out of the three mutants, NF8324 harbors exactly the same insertion as in the rsd-1 Tnt1 mutant NF11265. The defect in NF11217 is caused by a Tnt1 insertion in the previously described PLC gene; the site of this insertion is close to that found in a different mutant, NF0217. For mutant NF11044, we developed linkage markers that place the defective locus on chromosome 7. To further characterize co-segregation in NF11044, a mapping population has been created by crossing the mutant with other ecotypes: A17 and A20. We tested mutants and wild type plants with linkage marker A20 X NF11044 BC1F2 that segregates 3:1(wild ...
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Date: May 2015
Creator: Kadel, Khem L.
Partner: UNT Libraries

Combustion of TNT products in a confined explosion

Description: The effects of turbulent combustion of detonation products gases in a confined explosion are explored via laboratory experiments and high-resolution numerical simulations. The expanded products from the detonation of a TNT charge are rich in C and CO, which act as a fuel. When these hot gases mix with air, they are oxidized to CO2--thereby releasing 2482 Cal/g in addition to the 1093 Cal/g deposited by the detonation wave. In this case, the exothermic power is controlled by the turbulent mixing rate, rather than by chemistry. A kinetic law of turbulent combustion is suggested for this process. Pressure histories from the numerical simulations were in good agreement with the experimental measurements--demonstrating that the numerical model contains the fundamental mechanism that controls the exothermic process.
Date: June 18, 1999
Creator: Ferguson, R E; Kuhl, A L & Oppenheim, A K
Partner: UNT Libraries Government Documents Department

A quantitative method to detect explosives and selected semivolatiles in soil samples by Fourier transform infrared spectroscopy

Description: This paper describes a novel Fourier transform infrared (FTIR) spectroscopic method that can be used to rapidly screen soil samples from potentially hazardous waste sites. Samples are heated in a thermal desorption unit and the resultant vapors are collected and analyzed in a long-path gas cell mounted in a FTIR. Laboratory analysis of a soil sample by FTIR takes approximately 10 minutes. This method has been developed to identify and quantify microgram concentrations of explosives in soil samples and is directly applicable to the detection of selected volatile organics, semivolatile organics, and pesticides.
Date: June 1, 1995
Creator: Clapper-Gowdy, M.; Dermirgian, J. & Robitaille, G.
Partner: UNT Libraries Government Documents Department

Thermodynamics of Combustion in a Confined Explosion

Description: Considered here are explosions from condensed TNT charges--where the expanded detonation products gases are rich in C and CO [1]. Mixing with air causes oxidation/combustion [2], which dramatically increases the pressure in confined systems (vid. Fig. 1). We treat this as an Inverse Problem: infer fuel consumption from the measured pressure P {triple_bond} {bar p}(t)/p{sub i}. The Model expounded here represents a valuable tool for extracting the evolution of combustion system from a readily measurable quantity (pressure). The Model establishes the fuel consumption history as well as the evolution of thermodynamic solution (specific volumes, energies and densities) of the components that will generate the observed pressure profile. This solution in Thermodynamic (State) Space provides extraordinarily clear insight into the combustion process, which is normally clouded by a myriad of transport processes that occur in physical space.
Date: February 5, 2000
Creator: Kuhl, A.L.; Oppenheim, A.K. & Ferguson, R.E.
Partner: UNT Libraries Government Documents Department

SERDP ER-1376 Enhancement of In Situ Bioremediation of Energetic Compounds by Coupled Abiotic/Biotic Processes:Final Report for 2004 - 2006

Description: This project was initiated by SERDP to quantify processes and determine the effectiveness of abiotic/biotic mineralization of energetics (RDX, HMX, TNT) in aquifer sediments by combinations of biostimulation (carbon, trace nutrient additions) and chemical reduction of sediment to create a reducing environment. Initially it was hypothesized that a balance of chemical reduction of sediment and biostimulation would increase the RDX, HMX, and TNT mineralization rate significantly (by a combination of abiotic and biotic processes) so that this abiotic/biotic treatment may be a more efficient for remediation than biotic treatment alone in some cases. Because both abiotic and biotic processes are involved in energetic mineralization in sediments, it was further hypothesized that consideration for both abiotic reduction and microbial growth was need to optimize the sediment system for the most rapid mineralization rate. Results show that there are separate optimal abiotic/biostimulation aquifer sediment treatments for RDX/HMX and for TNT. Optimal sediment treatment for RDX and HMX (which have chemical similarities and similar degradation pathways) is mainly chemical reduction of sediment, which increased the RDX/HMX mineralization rate 100 to150 times (relative to untreated sediment), with additional carbon or trace nutrient addition, which increased the RDX/HMX mineralization rate an additional 3 to 4 times. In contrast, the optimal aquifer sediment treatment for TNT involves mainly biostimulation (glucose addition), which stimulates a TNT/glucose cometabolic degradation pathway (6.8 times more rapid than untreated sediment), degrading TNT to amino-intermediates that irreversibly sorb (i.e., end product is not CO2). The TNT mass migration risk is minimized by these transformation reactions, as the triaminotoluene and 2,4- and 2,6-diaminonitrotoluene products that irreversibly sorb are no longer mobile in the subsurface environment. These transformation rates are increased 13 times further by chemical reduction of sediment. Dithionite reduction alone is not an effective treatment for TNT (intermediates that irreversibly sorb are ...
Date: August 7, 2007
Creator: Szecsody, James E.; Comfort, Steve; Fredrickson, Herbert L.; Boparai, Hardiljeet K.; Devary, Brooks J.; Thompson, Karen T. et al.
Partner: UNT Libraries Government Documents Department

Numerical Simulations of Thermobaric Explosions

Description: A Model of the energy evolution in thermobaric explosions is presented. It is based on the two-phase formulation: conservation laws for the gas and particle phases along with inter-phase interaction terms. It incorporates a Combustion Model based on the mass conservation laws for fuel, air and products; source/sink terms are treated in the fast-chemistry limit appropriate for such gas dynamic fields. The Model takes into account both the afterburning of the detonation products of the booster with air, and the combustion of the fuel (Al or TNT detonation products) with air. Numerical simulations were performed for 1.5-g thermobaric explosions in five different chambers (volumes ranging from 6.6 to 40 liters and length-to-diameter ratios from 1 to 12.5). Computed pressure waveforms were very similar to measured waveforms in all cases - thereby proving that the Model correctly predicts the energy evolution in such explosions. The computed global fuel consumption {mu}(t) behaved as an exponential life function. Its derivative {dot {mu}}(t) represents the global rate of fuel consumption. It depends on the rate of turbulent mixing which controls the rate of energy release in thermobaric explosions.
Date: May 4, 2007
Creator: Kuhl, A L; Bell, J B; Beckner, V E & Khasainov, B
Partner: UNT Libraries Government Documents Department