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Sample records for high explosives

  1. Bioremediation of high explosives

    SciTech Connect

    Kitts, C.L.; Alvarez, M.A.; Hanners, J.L.; Ogden, K.L.; Vanderberg-Twary, L.; Unkefer, P.J.

    1995-09-01

    Manufacture and use of high explosives has resulted in contamination of ground water and soils throughout the world. The use of biological methods for remediation of high explosives contamination has received considerable attention in recent years. Biodegradation is most easily studied using organisms in liquid cultures. Thus, the amount of explosive that can be degraded in liquid culture is quite small. However, these experiments are useful for gathering basic information about the biochemical pathways of biodegradation, identifying appropriate organisms and obtaining rates of degradation. The authors` laboratory has investigated all three major areas of explosives bioremediation: explosives in solution, explosives in soil, and the disposal of bulk explosives from demilitarization operations. They investigated the three explosives most commonly used in modern high explosive formulations: 2,4,6-trinitrotoluene (TNT), hexahydro 1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX).

  2. High-nitrogen explosives

    SciTech Connect

    Naud, D.; Hiskey, M. A.; Kramer, J. F.; Bishop, R. L.; Harry, H. H.; Son, S. F.; Sullivan, G. K.

    2002-01-01

    The syntheses and characterization of various tetrazine and furazan compounds offer a different approach to explosives development. Traditional explosives - such as TNT or RDX - rely on the oxidation of the carbon and hydrogen atoms by the oxygen carrying nitro group to produce the explosive energy. High-nitrogen compounds rely instead on large positive heats of formation for that energy. Some of these high-nitrogen compounds have been shown to be less sensitive to initiation (e.g. by impact) when compared to traditional nitro-containing explosives of similar performances. Using the precursor, 3,6-bis-(3,5-dimethylpyrazol-1-yl)-s-tetrazine (BDT), several useful energetic compounds based on the s-tetrazine system have been synthesized and studied. The compound, 3,3{prime}-azobis(6-amino-s-tetrazine) or DAAT, detonates as a half inch rate stick despite having no oxygen in the molecule. Using perfluoroacetic acid, DAAT can be oxidized to give mixtures of N-oxide isomers (DAAT03.5) with an average oxygen content of about 3.5. This energetic mixture burns at extremely high rates and with low dependency on pressure. Another tetrazine compound of interest is 3,6-diguanidino-s-tetrazine(DGT) and its dinitrate and diperchlorate salts. DGT is easily synthesized by reacting BDT with guanidine in methanol. Using Caro's acid, DGT can be further oxidized to give 3,6-diguanidino-s-tetrazine-1,4-di-N-oxide (DGT-DO). Like DGT, the di-N-oxide can react with nitric acid or perchloric acid to give the dinitrate and the diperchlorate salts. The compounds, 4,4{prime}-diamino-3,3{prime}-azoxyfurazan (DAAF) and 4,4{prime}-diamino-3,3{prime}-azofurazan (DAAzF), may have important future roles in insensitive explosive applications. Neither DAAF nor DAAzF can be initiated by laboratory impact drop tests, yet both have in some aspects better explosive performances than 1,3,5-triamino-2,4,6-trinitrobenzene TATB - the standard of insensitive high explosives. The thermal stability of DAAzF is

  3. Introduction to High Explosives Science

    SciTech Connect

    Skidmore, Cary Bradford; Preston, Daniel N.

    2016-11-17

    These are a set of slides for educational outreach to children on high explosives science. It gives an introduction to the elements involved in this science: carbon, hydrogen, nitrogen, and oxygen. Combined, these form the molecule HMX. Many pictures are also included to illustrate explosions.

  4. Novel high explosive compositions

    DOEpatents

    Perry, D.D.; Fein, M.M.; Schoenfelder, C.W.

    1968-04-16

    This is a technique of preparing explosive compositions by the in-situ reaction of polynitroaliphatic compounds with one or more carboranes or carborane derivatives. One or more polynitroaliphatic reactants are combined with one or more carborane reactants in a suitable container and mixed to a homogeneous reaction mixture using a stream of inert gas or conventional mixing means. Ordinarily the container is a fissure, crack, or crevice in which the explosive is to be implanted. The ratio of reactants will determine not only the stoichiometry of the system, but will effect the quality and quantity of combustion products, the explosive force obtained as well as the impact sensitivity. The test values can shift with even relatively slight changes or modifications in the reaction conditions. Eighteen illustrative examples accompany the disclosure. (46 claims)

  5. High Explosive Radio Telemetry System

    SciTech Connect

    Bracht, R.R.; Crawford, T.R.; Johnson, R.L.; Mclaughlin, B.M.

    1998-11-04

    This paper overviews the High Explosive Radio Telemetry (HERT) system, under co-development by Los Alamos National Laboratories and Allied Signal Federal Manufacturing & Technologies. This telemetry system is designed to measure the initial performance of an explosive package under flight environment conditions, transmitting data from up to 64 sensors. It features high speed, accurate time resolution (10 ns) and has the ability to complete transmission of data before the system is destroyed by the explosion. In order to affect the resources and performance of a flight delivery vehicle as little as possible, the system is designed such that physical size, power requirements, and antenna demands are as small as possible.

  6. Detonation probabilities of high explosives

    SciTech Connect

    Eisenhawer, S.W.; Bott, T.F.; Bement, T.R.

    1995-07-01

    The probability of a high explosive violent reaction (HEVR) following various events is an extremely important aspect of estimating accident-sequence frequency for nuclear weapons dismantlement. In this paper, we describe the development of response curves for insults to PBX 9404, a conventional high-performance explosive used in US weapons. The insults during dismantlement include drops of high explosive (HE), strikes of tools and components on HE, and abrasion of the explosive. In the case of drops, we combine available test data on HEVRs and the results of flooring certification tests to estimate the HEVR probability. For other insults, it was necessary to use expert opinion. We describe the expert solicitation process and the methods used to consolidate the responses. The HEVR probabilities obtained from both approaches are compared.

  7. High explosive compound

    DOEpatents

    Crawford, Theodore C.

    1976-01-01

    1. A low detonation velocity explosive consisting essentially of a particulate mixture of ortho-boric acid and trinitrotoluene, said mixture containing from about 25 percent to about 65 percent by weight of ortho-boric acid, said ortho-boric acid comprised of from 60 percent to 90 percent of spherical particles having a mean particle size of about 275 microns and 10 percent to 40 percent of spherical particles having a particle size less than about 44 microns.

  8. Insensitive fuze train for high explosives

    SciTech Connect

    Cutting, Jack L.; Lee, Ronald S.; Von Holle, William G.

    1994-01-01

    A generic insensitive fuze train to initiate insensitive high explosives, such as PBXW-124. The insensitive fuze train uses a slapper foil to initiate sub-gram quantities of an explosive, such as HNS-IV or PETN. This small amount of explosive drives a larger metal slapper onto a booster charge of an insensitive explosive, such as UF-TATB. The booster charge initiates a larger charge of an explosive, such as LX-17, which in turn, initiates the insensitive high explosive, such as PBXW-124.

  9. Insensitive fuze train for high explosives

    SciTech Connect

    Cutting, J.L.; Lee, R.S.; Von Holle, W.G.

    1994-01-04

    A generic insensitive fuze train to initiate insensitive high explosives, such as PBXW-124 is described. The insensitive fuze train uses a slapper foil to initiate sub-gram quantities of an explosive, such as HNS-IV or PETN. This small amount of explosive drives a larger metal slapper onto a booster charge of an insensitive explosive, such as UF-TATB. The booster charge initiates a larger charge of an explosive, such as LX-17, which in turn, initiates the insensitive high explosive, such as PBXW-124. 3 figures.

  10. Insensitive fuze train for high explosives

    DOEpatents

    Cutting, J.L.; Lee, R.S.; Von Holle, W.G.

    1994-01-04

    A generic insensitive fuze train to initiate insensitive high explosives, such as PBXW-124 is described. The insensitive fuze train uses a slapper foil to initiate sub-gram quantities of an explosive, such as HNS-IV or PETN. This small amount of explosive drives a larger metal slapper onto a booster charge of an insensitive explosive, such as UF-TATB. The booster charge initiates a larger charge of an explosive, such as LX-17, which in turn, initiates the insensitive high explosive, such as PBXW-124. 3 figures.

  11. High temperature two component explosive

    DOEpatents

    Mars, James E.; Poole, Donald R.; Schmidt, Eckart W.; Wang, Charles

    1981-01-01

    A two component, high temperature, thermally stable explosive composition comprises a liquid or low melting oxidizer and a liquid or low melting organic fuel. The oxidizer and fuel in admixture are incapable of substantial spontaneous exothermic reaction at temperatures on the order of 475.degree. K. At temperatures on the order of 475.degree. K., the oxidizer and fuel in admixture have an activation energy of at least about 40 kcal/mol. As a result of the high activation energy, the preferred explosive compositions are nondetonable as solids at ambient temperature, and become detonable only when heated beyond the melting point. Preferable oxidizers are selected from alkali or alkaline earth metal nitrates, nitrites, perchlorates, and/or mixtures thereof. Preferred fuels are organic compounds having polar hydrophilic groups. The most preferred fuels are guanidinium nitrate, acetamide and mixtures of the two. Most preferred oxidizers are eutectic mixtures of lithium nitrate, potassium nitrate and sodium nitrate, of sodium nitrite, sodium nitrate and potassium nitrate, and of potassium nitrate, calcium nitrate and sodium nitrate.

  12. High-explosive driven crowbar switch

    DOEpatents

    Dike, Robert S.; Kewish, Jr., Ralph W.

    1976-01-13

    The disclosure relates to a compact explosive driven switch for use as a low resistance, low inductance crowbar switch. A high-explosive charge extrudes a deformable conductive metallic plate through a polyethylene insulating layer to achieve a hard current contact with a supportive annular conductor.

  13. Detonation in shocked homogeneous high explosives

    SciTech Connect

    Yoo, C.S.; Holmes, N.C.; Souers, P.C.

    1995-11-01

    We have studied shock-induced changes in homogeneous high explosives including nitromethane, tetranitromethane, and single crystals of pentaerythritol tetranitrate (PETN) by using fast time-resolved emission and Raman spectroscopy at a two-stage light-gas gun. The results reveal three distinct steps during which the homogeneous explosives chemically evolve to final detonation products. These are (1) the initiation of shock compressed high explosives after an induction period, (2) thermal explosion of shock-compressed and/or reacting materials, and (3) a decay to a steady-state representing a transition to the detonation of uncompressed high explosives. Based on a gray-body approximation, we have obtained the CJ temperatures: 3800 K for nitromethane, 2950 K for tetranitromethane, and 4100 K for PETN. We compare the data with various thermochemical equilibrium calculations. In this paper we will also show a preliminary result of single-shot time-resolved Raman spectroscopy applied to shock-compressed nitromethane.

  14. On the Violence of High Explosive Reactions

    SciTech Connect

    Tarver, C M; Chidester, S K

    2004-02-09

    High explosive reactions can be caused by three general energy deposition processes: impact ignition by frictional and/or shear heating; bulk thermal heating; and shock compression. The violence of the subsequent reaction varies from benign slow combustion to catastrophic detonation of the entire charge. The degree of violence depends on many variables, including the rate of energy delivery, the physical and chemical properties of the explosive, and the strength of the confinement surrounding the explosive charge. The current state of experimental and computer modeling research on the violence of impact, thermal, and shock-induced reactions is reviewed.

  15. Highly explosive nanosilicon-based composite materials

    NASA Astrophysics Data System (ADS)

    Clément, D.; Diener, J.; Gross, E.; Künzner, N.; Timoshenko, V. Yu.; Kovalev, D.

    2005-06-01

    We present a highly explosive binary system based on porous silicon layers with their pores filled with solid oxidizers. The porous layers are produced by a standard electrochemical etching process and exhibit properties that are different from other energetic materials. Its production is completely compatible with the standard silicon technology and full bulk silicon wafers can be processed and therefore a large number of explosive elements can be produced simultaneously. The application-relevant parameters: the efficiency and the long-term stability of various porous silicon/oxidizer systems have been studied in details. Structural properties of porous silicon, its surface termination, the atomic ratio of silicon to oxygen and the chosen oxidizers were optimized to achieve the highest efficiency of the explosive reaction. This explosive system reveals various possible applications in different industrial fields, e.g. as a novel, very fast airbag igniter.

  16. Nuclear Resonance Fluorescence Measurements of High Explosives

    SciTech Connect

    Caggiano, Joseph A.; Warren, Glen A.; Korbly, Steve; Hasty, R.; Klimenko, A.; Park, William H.

    2007-12-31

    Pacific Northwest National Laboratory and Passport Systems have collaborated to perform Nuclear Resonance Fluorescence experiments using several high quality high-explosive simulant samples. These measurements were conducted to determine the feasibility of finding and characterizing high explosive material by NRF interrogation. Electron beams of 5.1, 5.3, 8, and 10 MeV were used to produce bremsstrahlung photon beams, which irradiated the samples. The gamma-ray spectra were collected using high-purity germanium detectors. Nitrogen-to-carbon ratios of the high-explosive simulants were extracted from the 5.1 and 5.3 MeV data and compare favorably with accepted values. Analysis of the 8 and 10 MeV data is in progress; preliminary isotopic comparisons within the samples are consistent with the expected results.

  17. Ignition dynamics of high explosives

    SciTech Connect

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

    1999-04-01

    The laser ignition of the explosives HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, C{sub 4}H{sub 8}N{sub 8}O{sub 8}), {delta}-phase HMX, PBX 9501 (95% HMX, 2.5% Estane, 2.5% BDNPA/BDNPF), TATB (1,3,5-triamino-2,4,6-trinitrobenzene, C{sub 6}H{sub 6}N{sub 6}O{sub 6}), and PBX 9502 (95% TATB, 5% Kel-F) and aged PBX 9502 has been conducted with the intent to compare the relative sensitivities of those explosives and to investigate the effect of beam profile, binder addition, and porosity. It has been found that there was little difference between a gaussian beam and a top hat profile on the laser ignition of HMX. The authors observe that the addition of binder in the amounts present in PBX 9501 resulted in longer ignition delays than that of HMX. In contrast to HMX, the addition of binder to TATB in PBX 9502 shows no measurable effect. Porosity effects were considered by comparing the ignition of granular HMX and pressed HMX pellets. Porosity appears to increase ignition delay due to an increased effective absorption scale and increased convective heat loss. This porosity effect also resulted in longer ignition delays for {delta}-phase HMX than for {beta}-phase HMX. In order to simulate ignition in voids or cracks, the standard ignition experiment was modified to include a NaCl window placed at variable distances above the sample surface. When ignition experiments were performed at 29 W/cm{sup 2} and 38 W/cm{sup 2} a critical gap distance was observed of 6 {+-} 0.4 mm below which ignition was severely inhibited. This result underscores the importance of gas phase processes in ignition and illustrates that conditions can exist where simple ignition criteria such as surface temperature is inadequate.

  18. Explosive-driven, high speed, arcless switch

    DOEpatents

    Skogmo, P.J.; Tucker, T.J.

    1987-07-14

    An explosive-actuated, fast-acting arcless switch contains a highly conductive foil to carry high currents positioned adjacent a dielectric surface within a casing. At one side of the foil opposite the dielectric surface is an explosive which, when detonated, drives the conductive foil against the dielectric surface. A pattern of grooves in the dielectric surface ruptures the foil to establish a rupture path having a pattern corresponding to the pattern of the grooves. The impedance of the ruptured foil is greater than that of the original foil to divert high current to a load. Planar and cylindrical embodiments of the switch are disclosed. 7 figs.

  19. Explosive-driven, high speed, arcless switch

    DOEpatents

    Skogmo, P.J.; Tucker, T.J.

    1986-05-02

    An explosive-actuated, fast-acting arcless switch contains a highly conductive foil to carry high currents positioned adjacent a dielectric surface within a casing. At one side of the foil opposite the dielectric surface is an explosive which, when detonated, drives the conductive foil against the dielectric surface. A pattern of grooves in the dielectric surface ruptures the foil to establish a rupture path having a pattern corresponding to the pattern of the grooves. The impedance of the ruptured foil is greater than that of the original foil to divert high current to a load. Planar and cylindrical embodiments of the switch are disclosed.

  20. Explosive-driven, high speed, arcless switch

    DOEpatents

    Skogmo, Phillip J.; Tucker, Tillman J.

    1987-01-01

    An explosive-actuated, fast-acting arcless switch contains a highly conductive foil to carry high currents positioned adjacent a dielectric surface within a casing. At one side of the foil opposite the dielectric surface is an explosive which, when detonated, drives the conductive foil against the dielectric surface. A pattern of grooves in the dielectric surface ruptures the foil to establish a rupture path having a pattern corresponding to the pattern of the grooves. The impedance of the ruptured foil is greater than that of the original foil to divert high current to a load. Planar and cylindrical embodiments of the switch are disclosed.

  1. Electrostatic sensitivity of secondary high explosives

    SciTech Connect

    Campos, C.A.

    1980-06-01

    An Electrostatic Sensitivity Test System designed at Pantex was used to evaluate the secondary high explosives PETN, HMX, RDX, HNS I, HNS II and TATB. The purpose of this study was to establish test conditions for a standard electrostatic sensitivity test and measure baseline data of a few secondary explosives. Although secondary explosives are often considered quite insensitive to an electrostatic discharge, PETN, HMX, and RDX were initiated. Several external elements to the high explosive were found to have an influence on sensitivity. Initiation appeared to be dependent on the nature of the discharge current curve. Those elements recognized as having a significant effect on the results were held constant in this study. These included: distance between discharge plates; sample moisture content; material density; and system resistance, capacitance and inductance. However, no attempt was made in this study to determine the extent to which the high explosive response to electrostatic discharge is affected by these factors since such correlation is not necessary to determine relative sensitivities.

  2. Equation of state of insensitive high explosives

    SciTech Connect

    Ree, F H; Van Thiel, M; Viecelli, J A

    1998-08-12

    Detonation of an insensitive high explosive formulated with a fluorine containing binder produces a large amount of condensed carbon and gaseous HF product, which transforms into CF{sub 4} as the pressure is increased. The former (carbon condensation) is characterized by slow energy release, while the latter (HF) has no shockwave data. We have identified that these two items are the key factors, which make reliable prediction of the performance of an insensitive high explosive very difficult. This paper describes physical models to address these issues and apply the models to analyze experimental data of LX-17.

  3. High Energy Explosive Yield Enhancer Using Microencapsulation.

    DTIC Science & Technology

    The invention consists of a class of high energy explosive yield enhancers created through the use of microencapsulation techniques. The... microcapsules consist of combinations of highly reactive oxidizers that are encapsulated in either passivated inorganic fuels or inert materials and inorganic...fuels. Depending on the application, the availability of the various oxidizers and fuels within the microcapsules can be customized to increase the

  4. Criticality safety in high explosives dissolution

    SciTech Connect

    Troyer, S.D.

    1997-06-01

    In 1992, an incident occurred at the Pantex Plant in which the cladding around a fissile material component (pit) cracked during dismantlement of the high explosives portion of a nuclear weapon. Although the event did not result in any significant contamination or personnel exposures, concerns about the incident led to the conclusion that the current dismantlement process was unacceptable. Options considered for redesign, dissolution tooling design considerations, dissolution tooling design features, and the analysis of the new dissolution tooling are summarized. The final tooling design developed incorporated a number of safety features and provides a simple, self-contained, low-maintenance method of high explosives removal for nuclear explosive dismantlement. Analyses demonstrate that the tooling design will remain subcritical under normal, abnormal, and credible accident scenarios. 1 fig.

  5. Securing Infrastructure from High Explosive Threats

    SciTech Connect

    Glascoe, L; Noble, C; Reynolds, J; Kuhl, A; Morris, J

    2009-03-20

    Lawrence Livermore National Laboratory (LLNL) is working with the Department of Homeland Security's Science and Technology Directorate, the Transportation Security Administration, and several infrastructure partners to characterize and help mitigate principal structural vulnerabilities to explosive threats. Given the importance of infrastructure to the nation's security and economy, there is a clear need for applied research and analyses (1) to improve understanding of the vulnerabilities of these systems to explosive threats and (2) to provide decision makers with time-critical technical assistance concerning countermeasure and mitigation options. Fully-coupled high performance calculations of structural response to ideal and non-ideal explosives help bound and quantify specific critical vulnerabilities, and help identify possible corrective schemes. Experimental validation of modeling approaches and methodologies builds confidence in the prediction, while advanced stochastic techniques allow for optimal use of scarce computational resources to efficiently provide infrastructure owners and decision makers with timely analyses.

  6. High Voltage Application of Explosively Formed Fuses

    SciTech Connect

    Tasker, D.G.; Goforth, J.H.; Fowler, C.M.; Lopez, E.M.; Oona, H.; Marsh, S.P.; King, J.C.; Herrera, D.H.; Torres, D.T.; Sena, F.C.; Martinez, E.C.; Reinovsky, R.E.; Stokes, J.L.; Tabaka, L.J.; Kiuttu, G.; Degnan, J.

    1998-10-18

    At Los Alamos, the authors have primarily applied Explosively Formed Fuse (EFF) techniques to high current systems. In these systems, the EFF has interrupted currents from 19 to 25 MA, thus diverting the current to low inductance loads. The magnitude of transferred current is determined by the ratio of storage inductance to load inductance, and with dynamic loads, the current has ranged from 12 to 20 MA. In a system with 18 MJ stored energy, the switch operates at a power up to 6 TW. The authors are now investigating the use of the EFF technique to apply high voltages to high impedance loads in systems that are more compact. In these systems, they are exploring circuits with EFF lengths from 43 to 100 cm, which have storage inductances large enough to apply 300 to 500 kV across high impedance loads. Experimental results and design considerations are presented. Using cylindrical EFF switches of 10 cm diameter and 43 cm length, currents of approximately 3 MA were interrupted producing {approximately}200 kV. This indicate s the switch had an effective resistance of {approximately}100 m{Omega} where 150--200 m{Omega} was expected. To understand the lower performance, several parameters were studied, including: electrical conduction through the explosive products; current density; explosive initiation; insulator type; conductor thickness; and so on. The results show a number of interesting features, most notably that the primary mechanism of switch operation is mechanical and not electrical fusing of the conductor. Switches opening on a 10 to 10 {micro}s time scale with resistances starting at 50 {micro}{Omega} and increasing to perhaps 1 {Omega} now seem possible to construct, using explosive charges as small as a few pounds.

  7. High Voltage Applications of Explosively Formed Fuses

    NASA Astrophysics Data System (ADS)

    Tasker, D. G.; Goforth, J. H.; Fowler, C. M.; Herrera, D. H.; King, J. C.; Lopez, E. A.; Martinez, E. C.; Oona, H.; Marsh, S. P.; Reinovsky, R. E.; Stokes, J.; Tabaka, L. J.; Torres, D. T.; Sena, F. C.; Kiuttu, G.; Degnan, J.

    2004-11-01

    At Los Alamos, we have primarily applied Explosively Formed Fuse (EFF) techniques to high current systems. In these systems, the EFF has interrupted currents from 19-25 MA, thus diverting the current to low inductance loads. The transferred current magnitude is determined by the ratio of storage inductance to load inductance and, with dynamic loads, the current has ranged from 12-20 MA. In a system with 18 MJ stored energy, the switch operates at a power of up to 6 TW. We are now investigating the use of the EFF technique to apply high voltages to high impedance loads in systems that are more compact. In these systems we are exploring circuits with EFF lengths from 43-100 cm, which have storage inductances large enough to apply 300-500 kV across high impedance loads. Experimental results and design considerations are presented. Using cylindrical EFF switches of 10 cm diameter and 43 cm length, currents of approximately 3 MA were interrupted producing ~200 kV. This indicates the switch had an effective resistance of ~100 mΩ where 150-200 mΩ was expected. To understand the lower performance, several parameters were studied including electrical conduction through the explosive products; current density; explosive initiation; insulator type and conductor thickness. The results show a number of interesting features, most notably that the primary mechanism of switch operation is mechanical and not electrical fusing of the conductor. Switches opening on a 1-10 μs time scale with resistances starting at 50 μΩ and increasing to perhaps 1 Ω now seem possible to construct using explosive charges as small as a few pounds.

  8. Internal Detonation Velocity Measurements Inside High Explosives

    SciTech Connect

    Benterou, J; Bennett, C V; Cole, G; Hare, D E; May, C; Udd, E

    2009-01-16

    In order to fully calibrate hydrocodes and dynamic chemistry burn models, initiation models and detonation models of high explosives, the ability to continuously measure the detonation velocity within an explosive is required. Progress on an embedded velocity diagnostic using a 125 micron diameter optical fiber containing a chirped fiber Bragg grating is reported. As the chirped fiber Bragg grating is consumed by the moving detonation wave, the physical length of the unconsumed Bragg grating is monitored with a fast InGaAs photodiode. Experimental details of the associated equipment and data in the form of continuous detonation velocity records within PBX-9502 are presented. This small diameter fiber sensor has the potential to measure internal detonation velocities on the order of 10 mm/{micro}sec along path lengths tens of millimeters long.

  9. High pressure-resistant nonincendive emulsion explosive

    DOEpatents

    Ruhe, Thomas C.; Rao, Pilaka P.

    1994-01-01

    An improved emulsion explosive composition including hollow microspheres/bulking agents having high density and high strength. The hollow microspheres/bulking agents have true particle densities of about 0.2 grams per cubic centimeter or greater and include glass, siliceous, ceramic and synthetic resin microspheres, expanded minerals, and mixtures thereof. The preferred weight percentage of hollow microspheres/bulking agents in the composition ranges from 3.0 to 10.0 A chlorinated paraffin oil, also present in the improved emulsion explosive composition, imparts a higher film strength to the oil phase in the emulsion. The emulsion is rendered nonincendive by the production of sodium chloride in situ via the decomposition of sodium nitrate, a chlorinated paraffin oil, and sodium perchlorate. The air-gap sensitivity is improved by the in situ formation of monomethylamine perchlorate from dissolved monomethylamine nitrate and sodium perchlorate. The emulsion explosive composition can withstand static pressures to 139 bars and dynamic pressure loads on the order of 567 bars.

  10. Three Decades of Explosive High Energy Transients

    NASA Technical Reports Server (NTRS)

    Kouveliotou, Chryssa

    2013-01-01

    Gamma-Ray Bursts are the most brilliant explosions in space. The first GRB was discovered on 1967, just 40 years ago. It took several years and multiple generations of space and ground instruments to unravel some of the mysteries of this phenomenon. However, many questions remain open today. I will discuss the history, evolution and current status of the GRB field and its contributions in our understanding of the transient high energy sky. Finally, I will describe how GRBs can be utilized in future missions as tools, to probe the cosmic chemical evolution of the Universe and the star formation rates.

  11. High-strain rate testing of HMX-based explosive

    NASA Astrophysics Data System (ADS)

    John, Henry J.; Alamo, Mike F.

    2000-04-01

    A split Hopkinson pressure bar (SHPB) was used to measure the mechanical behavior of Navy explosive PBXC-129 (a high-solids-loaded explosive material) with strain rates up to ˜3500 s-1. The PBXC-129's high-strain response is typical of other explosive and propellant behavior. At higher strain rates, the PBXC-129 shows significant stiffening with a possible reaction. Stress-strain curves and material properties for PBXC-129 are presented in this paper.

  12. High-Explosives Applications Facility (HEAF)

    NASA Astrophysics Data System (ADS)

    Morse, J. L.; Weingart, R. C.

    1989-03-01

    This Safety Analysis Report (SAR) reviews the safety and environmental aspects of the High Explosives Applications Facility (HEAF). Topics covered include the site selected for the HEAF, safety design criteria, operations planned within the facility, and the safety and environmental analyses performed on this project to date. Provided in the Summary section is a review of hazards and the analyses, conclusions, and operating limits developed in this SAR. Appendices provide supporting documents relating to this SAR. This SAR is required by the LLNL Health and Safety Manual and DOE Order 5481.1B(2) to document the safety analysis efforts. The SAR was assembled by the Hazards Control Department, B-Division, and HEAF project personnel. This document was reviewed by B Division, the Chemistry Department, the Hazards Control Department, the Laboratory Associate Director for Administration and Operations, and the Associate Directors ultimately responsible for HEAF operations.

  13. Multistage reaction pathways in detonating high explosives

    SciTech Connect

    Li, Ying; Kalia, Rajiv K.; Nakano, Aiichiro; Nomura, Ken-ichi; Vashishta, Priya

    2014-11-17

    Atomistic mechanisms underlying the reaction time and intermediate reaction products of detonating high explosives far from equilibrium have been elusive. This is because detonation is one of the hardest multiscale physics problems, in which diverse length and time scales play important roles. Here, large spatiotemporal-scale reactive molecular dynamics simulations validated by quantum molecular dynamics simulations reveal a two-stage reaction mechanism during the detonation of cyclotrimethylenetrinitramine crystal. Rapid production of N{sub 2} and H{sub 2}O within ∼10 ps is followed by delayed production of CO molecules beyond ns. We found that further decomposition towards the final products is inhibited by the formation of large metastable carbon- and oxygen-rich clusters with fractal geometry. In addition, we found distinct unimolecular and intermolecular reaction pathways, respectively, for the rapid N{sub 2} and H{sub 2}O productions.

  14. Mesoscale modeling of metal-loaded high explosives

    SciTech Connect

    Bdzil, John Bohdan; Lieberthal, Brandon; Srewart, Donald S

    2010-01-01

    We describe a 3D approach to modeling multi-phase blast explosive, which is primarily condensed explosive by volume with inert embedded particles. These embedded particles are uniform in size and placed on the array of a regular lattice. The asymptotic theory of detonation shock dynamics governs the detonation shock propagation in the explosive. Mesoscale hydrodynamic simulations are used to show how the particles are compressed, deformed, and accelerated by the high-speed detonation products flow.

  15. Mechanisms of laser-induced photocatalytic decomposition of high explosives

    NASA Astrophysics Data System (ADS)

    Mitrofanov, Anatoly; Zverev, Anton; Rashkeev, Sergey; Tsyshevsky, Roman; Kuklja, Maija

    Using laser irradiation for triggering explosive decomposition of high density energy materials opens up new opportunities in design of safe optical detonators by removing primary explosive from the devices. Precise tuning of sensitivity to initiation of detonation via photo-excitation appears challenging because all secondary explosives are insulators with the band gap of 4-8 eV. We will discuss our combined experimental and theoretical studies that suggest feasible mechanisms of photocatalytic decomposition of explosives triggered by the laser excitation with the energy of 1.17 - 2.3 eV and the wavelength of 1064-532 nm. The first approach considers tuning the optical absorption via the controlled modification of the electronic structure of the explosive-metal oxide interfaces. The second approach involves incorporating photoactive organic molecules in the crystalline matrix of the explosive material.

  16. Energetic nanocomposites for detonation initiation in high explosives without primary explosives

    NASA Astrophysics Data System (ADS)

    Comet, Marc; Martin, Cédric; Klaumünzer, Martin; Schnell, Fabien; Spitzer, Denis

    2015-12-01

    The mixing of aluminum nanoparticles with a metal containing oxidizer (here, WO3 or Bi2(SO4)3) gives reactive materials called nanothermites. In this research, nanothermites were combined with high explosive nanoparticles (RDX) to prepare energetic nanocomposites. These smart nanomaterials have higher performances and are much less hazardous than primary explosives. Their flame propagation velocity can be tuned from 0.2 to 3.5 km/s, through their explosive content. They were used to initiate the detonation of a high explosive, the pentaerythritol tetranitrate. The pyrotechnic transduction of combustion into detonation was achieved with short length systems (<2 cm) and small amounts of energetic nanocomposites (˜100 mg) in semi-confined systems.

  17. Behavior of Plastic Bonded Composite Explosives During High Acceleration

    NASA Astrophysics Data System (ADS)

    Lanzerotti, Y.

    1998-03-01

    The mechanical behavior of plastic bonded composite explosives has been studied during high acceleration in an ultracentrifuge. The pressed explosives studied include LX-14 [95% HMX (cyclotetramethylene- tetranitramine), 5% Estane], Composition A3 type II [91% RDX (cyclotrimethylene-trinitramine), 99% BDNPF (bis-dinitropropyl acetal formal), 6% CAB (cellulose acetate butyrate)], and PAX-3 (85% HMX, 9% BDNPF, 6% CAB/25% Aluminum). The fracture strength of LX-14 is greater than all pressed explosives studied to date. The fracture strength of Composition A3 type II is smaller than all pressed explosives studied to date.

  18. Equation of state of unreacted high explosives at high pressures

    SciTech Connect

    Yoo, C-S

    1998-08-14

    Isotherms of unreacted high explosives (HMX, RDX, and PETN) have been determined to quasi-hydrostatic high pressures below 45 GPa, by using a diamond-anvil cell angle-resolved synchrotron x-ray diffraction method. The equation-of-state parameters (bulk modulus Bo, and its derivatives B' ) are presented for the 3rd-order Birch-Murnaghan formula based on the measured isotherms. The results are also used to retrieve unreacted Hugoniots in these high explosives and to develop the equations of state and kinetic models for composite high explolsivcs such as XTX-8003 and LX-04. The evidence of shear-induced chemistry of HMX in non-hydrostatic conditions is also presented.

  19. Contained high explosive firing facility (CHEFF)

    SciTech Connect

    Stacy, H.L.; Seitz, W.L.; Wackerle, J.; Polcyn, M.; Esparza, E.

    1993-08-01

    A cylindrical vessel capable of totally containing the products and shrapnel resulting from the detonation of 10 kg of TNT (or equivalent) has been designed and built by Southwest Research Institute for and according to the requirements of the Detonation Systems Group (M-7) of Los Alamos National Laboratory. The vessel is 6.0-m long by 3.6-m diameter and is manufactured of 50-mm (elliptical end caps) and 38-mm (cylindrical walls) thick high-strength steel (HY-100). The cylindrical walls of the vessel are lined with 13-mm thick replaceable steel plates for shrapnel protection. The floor is made of steel-covered concrete. Ten large-aperture (254 mm) optical ports are available for instrumentation and four ports are provided for cabling and plumbing. Two qualifying detonation tests of 8.8 kg of C-4 explosive (equivalent to 10 kg TNT) have shown that the maximum strain produced is less than 78% of the elastic limit. The vessel is installed in a converted outdoor firing facility that has been modified to include an insulated and heated metal building to house the vessel and additional instrumentation. A computer-based system for data acquisition, firing control, and the monitoring of vessel response is described.

  20. High explosives reaction model and its application to booster performance

    SciTech Connect

    Tang, P.K.

    1989-01-01

    Initiation of insensitive high explosives requires a boosting system using more sensitive and usually more energetic explosives. However, problems arise if the booster material is too energetic. The initiability of some insensitive but less energetic high explosives can be enhanced by lowering the density and decreasing the grain size or by adding a sensitive component; thus these explosives can be used as booster materials. This paper presents a unified initiation and detonation reaction model and then the simulation of the development of the detonation wave in a PBX-9502 main charge using three booster explosives: low-density superfine TATB, low-density ultrafine TATB, and X-0407. The last two are found to be acceptable for booster application. 12 refs., 5 figs.

  1. Investigation Of Vapor Explosion Mechanisms Using High Speed Photography

    NASA Astrophysics Data System (ADS)

    Armstrong, Donn R.; Anderson, Richard P.

    1983-03-01

    The vapor explosion, a physical interaction between hot and cold liquids that causes the explosive vaporization of the cold liquid, is a hazard of concern in such diverse industries as metal smelting and casting, paper manufacture, and nuclear power generation. Intensive work on this problem worldwide, for the past 25 years has generated a number of theories and mechanisms proposed to explain vapor explosions. High speed photography has been the major instrument used to test the validity of the theories and to provide the observations that have lead to new theories. Examples are given of experimental techniques that have been used to investigate vapor explosions. Detailed studies of specific mechanisms have included microsecond flash photograph of contact boiling and high speed cinematography of shock driven breakup of liquid drops. Other studies looked at the explosivity of various liquid pairs using cinematography inside a pulsed nuclear reactor and x-ray cinematography of a thermite-sodium interaction.

  2. Flying-plate detonator using a high-density high explosive

    DOEpatents

    Stroud, John R.; Ornellas, Donald L.

    1988-01-01

    A flying-plate detonator containing a high-density high explosive such as benzotrifuroxan (BTF). The detonator involves the electrical explosion of a thin metal foil which punches out a flyer from a layer overlying the foil, and the flyer striking a high-density explosive pellet of BTF, which is more thermally stable than the conventional detonator using pentaerythritol tetranitrate (PETN).

  3. Light Initiated High Explosives (LIHE) Test Technique and Capabilities

    NASA Astrophysics Data System (ADS)

    Covert, Timothy

    2009-06-01

    The Light Initiated High Explosives (LIHE) test facility has been re-established and chartered to impart impulsive loads to a variety of targets. This loading is achieved through the detonation of a primary explosive applied directly to the target surface using a robotic spraying system. Using light as the initiating mechanism ensures virtually simultaneous loading. Uniform, discontinuous, or graded explosive loading conditions are achievable over complex shapes with the LIHE process. This direct detonation technique is a demonstrated capability at the LIHE facility. Test results will be presented. In addition to the direct detonation technique, the LIHE facility is developing the capability to explosively accelerate a thin flyer plate to impact various test targets. This explosively accelerated flyer plate (X-Flyer) will enable pressure control during impulsive loading. By controlling flyer density (material), thickness, velocity, and acceleration gap, the impact pressure amplitude and pulse duration can be controlled. Similar to the direct detonation technique, a primary explosive is robotically sprayed onto the flyer plate and subsequently detonated using an intense flash of light. Through the control of the explosive deposition and flyer gap, virtually simultaneous impact is achievable for either uniform or graded loading conditions. X-Flyer test results will be presented.

  4. Treatment and recycle of high explosive contaminated water

    SciTech Connect

    Locke, J.G.

    1994-09-01

    A polysulfone ultrafilter membrane having a 0.04-{micro}m pore opening has been used to filter high explosive contaminated water. The water is being recycled for the coolant used during the machining of high explosive billets. High explosive contaminated wastewater is generated from the machining of high explosives at Pantex Plant. The water is used as the coolant during the machining operation. Typically, the water flow rate is from 2 to 3 gallons per minute. The water must be tempered to about room temperature so that it does not affect the dimensions of the explosive piece being machined. In normal operations, the wastewater and cuttings are allowed to flow to a centralized collection system. The solid explosives are separated from the water using a filtration and recycle system. The wastewater is collected in an air agitated receiving tank or sump. It is pumped from the sump to a settling cone where the solid particles are decanted off of the bottom. The overflow from the cone is collected in another tank and then pumped through two cyclone separators operated in series. This water is also collected in a holding tank prior to final filtration through a 25-{micro}m filter. The effluent from the particle filter flows through two activated carbon filters operated in series prior to being discharged to a drainage ditch. This results in an average discharge of about 2,000 gallons per operating day from Building 11-50.

  5. An Orientation to Explosive Safety.

    ERIC Educational Resources Information Center

    Harris, Betty W.

    1987-01-01

    Provides an overview of various types of explosives. Classifies and describes explosives as initiating or primary explosives, low explosives, and high (secondary explosives). Discusses detonating devices, domestic explosive systems, the sensitivity of explosives, explosive reactions, and emergency responses. (TW)

  6. An Orientation to Explosive Safety.

    ERIC Educational Resources Information Center

    Harris, Betty W.

    1987-01-01

    Provides an overview of various types of explosives. Classifies and describes explosives as initiating or primary explosives, low explosives, and high (secondary explosives). Discusses detonating devices, domestic explosive systems, the sensitivity of explosives, explosive reactions, and emergency responses. (TW)

  7. Method for enhancing stability of high explosives, for purposes of transport or storage, and the stabilized high explosives

    DOEpatents

    Nutt, Gerald L.

    1991-01-01

    The stability of porous solid high explosives, for purposes of transport or storage, is enhanced by reducing the sensitivity to shock initiation of a reaction that leads to detonation. The pores of the explosive down to a certain size are filled under pressure with a stable, low melt temperature material in liquid form, and the combined material is cooled so the pore filling material solidifies. The stability can be increased to progressively higher levels by filling smaller pores. The pore filling material can be removed, at least partially, by reheating above its melt temperature and drained off so that the explosive is once more suitable for detonation.

  8. Design of a hypersonic waterjet apparatus driven by high explosives

    SciTech Connect

    Weeks, Brandon L.; Klosterman, John; Worsey, Paul N.

    2001-08-01

    The design and construction of a hypersonic waterjet apparatus is described. Jet velocities from 0.5 to 5 km/s have been achieved using a high explosive charge. Images are obtained in situ on various target substrates using a high-speed framing camera. Experimental results are shown for the impact of high velocity waterjets on propellants and high explosive samples. By observing the impact of the waterjet at a wide range of velocities a safety threshold can be determined where no reaction takes place.

  9. Radio frequency overview of the high explosive radio telemetry project

    SciTech Connect

    Bracht, R.; Dimsdle, J.; Rich, D.; Smith, F.

    1998-12-31

    High explosive radio telemetry (HERT) is a project that is being developed jointly by Los Alamos National Laboratory and AlliedSignal Federal Manufacturing and Technologies. The ultimate goal is to develop a small, modular telemetry system capable of high-speed detection of explosive events, with an accuracy on the order of 10 nanoseconds. The reliable telemetry of this data, from a high-speed missile trajectory, is a very challenging opportunity. All captured data must be transmitted in less than 20 microseconds of time duration. This requires a high bits/Hertz microwave telemetry modulation code to insure transmission of the data with the limited time interval available.

  10. High-frame rate thermal imagery of Strombolian explosions: Implications for explosive and infrasonic source dynamics

    NASA Astrophysics Data System (ADS)

    Delle Donne, Dario; Ripepe, Maurizio

    2012-09-01

    Explosive activity at Stromboli volcano is analyzed using a high-frame rate (50 Hz) thermal camera and differential pressure transducers. We develop a thermal image-based decomposition method to derive vertical and horizontal exit velocities of the explosive cloud. Peak vertical velocity ranges between 23 and 203 m/s, slightly higher than previous estimates and rapidly decreasing to a constant value of 30-50 m/s within the first ˜0.1 s. Plume velocities are consistent with an elongated cloud expanding much faster vertically than horizontally and indicating the interaction with the conduit wall. Considering a vent radius of ˜2 m we estimate a volumetric flux of 200-600 m3/s, which converts to total volumes of gas-particles of 103-104 m3 for a single eruption. These volumes are proportional to the thermal energy recorded by the camera, providing a means to convert thermal radiance to volumes. Comparing the thermal onset of the explosions with the arrival time of the acoustic pressure, we demonstrate that infrasound is propagating 0.14-1.7 s ahead of the explosive front. The time difference between thermal and acoustic onsets constrains the infrasonic source within the conduit at 15-35 m below the crater rim. Peak amplitudes of acoustic pressure show a power law relationship (p ˜ U2) with the exit vertical velocities consistent with the energy balance of a two-phase flow rapidly accelerated in the conduit by gas decompression. Our results support monopole isotropic acoustic radiation of a source embedded within the conduit walls and indicate that explosive dynamics undergo strong accelerations of 103-104 m/s2.

  11. Subnanosecond measurements of detonation fronts in solid high explosives

    SciTech Connect

    Sheffield, S.A.; Bloomquist, D.D.; Tarver, C.M.

    1984-04-15

    Detonation fronts in solid high explosives have been examined through measurements of particle velocity histories resulting from the interaction of a detonation wave with a thin metal foil backed by a water window. Using a high time resolution velocity-interferometer system, experiments were conducted on three explosives: a TATB (1,3,5-triamino-trinitrobenzene)-based explosive called PBX-9502, TNT (2,4,6-Trinitrotoluene), and CP (2-)5-cyanotetrazolato) pentaamminecobalt )III) perchlorate). In all cases, detonation-front rise times were found to be less than the 300 ps resolution of the interferometer system. The thermodynamic state in the front of the detonation wave was estimated to be near the unreacted state determined from an extrapolation of low-pressure unreacted Hugoniot data for both TNT and PBX-9502 explosives. Computer calculations based on an ignition and growth model of a Zeldovich--von Neumann--Doering (ZND) detonation wave show good agreement with the measurements. By using the unreacted Hugoniot and a JWL equation of state for the reaction products, we estimated the initial reaction rate in the high explosive after the detonation wave front interacted with the foil to be 40 ..mu..s/sup -1/ for CP, 60 ..mu..s/sup -1/ for TNT, and 80 ..mu..s/sup -1/ for PBX-9502. The shape of the profiles indicates the reaction rate decreases as reaction proceeds.

  12. High explosive programmed burn in the FLAG code

    SciTech Connect

    Mandell, D.; Burton, D.; Lund, C.

    1998-02-01

    The models used to calculate the programmed burn high-explosive lighting times for two- and three-dimensions in the FLAG code are described. FLAG uses an unstructured polyhedra grid. The calculations were compared to exact solutions for a square in two dimensions and for a cube in three dimensions. The maximum error was 3.95 percent in two dimensions and 4.84 percent in three dimensions. The high explosive lighting time model described has the advantage that only one cell at a time needs to be considered.

  13. Are amino groups advantageous to insensitive high explosives (IHEs)?

    PubMed

    Cao, Xia; Wen, Yushi; Xiang, Bin; Long, Xinping; Zhang, Chaoyang

    2012-10-01

    There is usually a contradiction between increasing energy densities and reducing sensitivities of explosives. The explosives with both high energy densities and low sensitivities, or the so-called insensitive high explosives (IHEs), are desirable in most cases. It seems from applied explosives that amino groups are advantageous to IHE but the amount of amino groups contained IHEs is very limited. To make this clear, we present systemic examinations of the effects on the two properties stressed in IHEs after introducing amino groups to different molecular skeletons. As a result, the amino groups on resonant sites to nitro groups in conjugated systems can improve distinctly sensitivities and change energy densities in terms of oxygen balance; while the amino groups in unconjugated systems can hardly increase energy densities and usually cause increased sensitivities. It agrees well with a fact that almost all the molecules of applied amino group contained explosives possess conjugated skeletons. We therefore confirm that if amino groups are introduced resonantly to a nitro group in a conjugated system and the introduction improves OB, they are advantageous to IHEs.

  14. Equations of State and High-Pressure Phases of Explosives

    NASA Astrophysics Data System (ADS)

    Peiris, Suhithi M.; Gump, Jared C.

    Energetic materials, being the collective name for explosives, propellants, pyrotechnics, and other flash-bang materials, span a wide range of composite chemical formulations. Most militarily used energetics are solids composed of particles of the pure energetic material held together by a binder. Commonly used binders include various oils, waxes, and polymers or plasticizers, and the composite is melt cast, cured, or pressed to achieve the necessary mechanical properties (gels, putties, sheets, solid blocks, etc.) of the final energetic material. Mining, demolition, and other industries use liquid energetics that are similarly composed of an actual energetic material or oxidizer together with a fuel, that is to be mixed and poured for detonation. Pure energetic materials that are commonly used are nitroglycerine, ammonium nitrate, ammonium or sodium perchlorate, trinitrotoluene (TNT), HMX, RDX, and TATB. All of them are molecular materials or molecular ions that when initiated or insulted undergoes rapid decomposition with excessive liberation of heat resulting in the formation of stable final products. When the final products are gases, and they are rapidly produced, the sudden pressure increase creates a shock wave. When decomposition is so rapid that the reaction moves through the explosive faster than the speed of sound in the unreacted explosive, the material is said to detonate. Typically, energetic materials that undergo detonation are known as high explosives (HEs) and energetic materials that burn rapidly or deflagrate are known as low explosives and/or propellants.

  15. Sensitivity of once-shocked, weathered high explosives

    SciTech Connect

    Williams, K.L.; Harris, B.W.

    1998-07-01

    Effects caused by stimulating once-shocked, weathered high explosives (OSW-HE) are investigated. The sensitivity of OSW-HE to mechanical stimuli was determined using standard industry tests. Some initial results are given. Pieces of OSW-HE were collected from active and inactive firing sites and from an area surrounding a drop tower at Los Alamos where skid and spigot tests were done. Samples evaluated were cast explosives or plastic bonded explosive (PBX) formulations containing cyclotrimethylenetrinitramine (RDX), cyclotetramethylene tetranitramine (HMX), 2,4,6-trinitrotoluene (TNT), mock or inert HE [tris(beta-chloroethyl)phosphate (CEF)], barium nitrate, cyanuric acid, talc, and Kel-F. Once-shocked, weathered LX-10 Livermore explosive [HMX/Viton A, (95/5 wt %)], PBX 9011 [HMX/Estane, (90/10 wt %)], PBX 9404 [HMX/nitrocellulose, tris(beta-chloroethyl) phosphate, (94/3/3 wt %)], Composition B or cyclotol (TNT/RDX explosives), and PBX 9007 (90% RDX, 9.1% styrene, 0.5% dioctyl phthalate, and 0.45 resin) were subjected to the hammer test, the drop-weight impact sensitivity test, differential thermal analysis (DTA), the spark test, the Henkin`s critical temperature test, and the flame test. Samples were subjected to remote, wet cutting and drilling; remote, liquid-nitrogen-cooled grinding and crushing; and scanning electron microscope (SEM) surface analyses for morphological changes.

  16. Detonation temperature of high explosives from structural parameters.

    PubMed

    Keshavarz, Mohammad Hossein

    2006-10-11

    A new scheme is introduced for calculating detonation temperature of different classes of high explosives. The ratio of oxygen to carbon and hydrogen to oxygen as well as specific structural parameters are the fundamental factors in the new method. An empirical new correlation is used to calculate detonation temperature of energetic compounds without considering heat contents of explosives and detonation products. Calculated detonation temperatures for both pure and explosive formulations show good agreement with respect to measured detonation temperatures and complicated computer code using BKWR and BKWS equations of state. Predicted detonation temperatures have root-mean-square (rms) percent deviation of 4.6, 14.2 and 4.6 from measured values for new method, BKWR and BKWS equations of state, respectively.

  17. High Explosive Deonation Threshold Sensitivity Due to Multiple Fragment Impacts

    SciTech Connect

    Georgevich, V; Pincosy, P; Chase, J

    2004-01-07

    Fragments, bullets or projectiles can initiate a detonation in a high explosive (HE). For this to happen certain critical conditions need to be exceeded. For a given explosive, these critical conditions are the projectile velocity, the projectile size and shape, and the projectile material properties. A lot of work has been done in the area of metal shaped charge jets and individual fragments impacting the HE. One major gap in understanding initiation phenomena is the effect of multiple fragment impact. This study shows that multiple fragments can lower the fragment size and the kinetic energy thresholds.

  18. On high explosive launching of projectiles for shock physics experiments

    NASA Astrophysics Data System (ADS)

    Swift, Damian C.; Forest, Charles A.; Clark, David A.; Buttler, William T.; Marr-Lyon, Mark; Rightley, Paul

    2007-06-01

    The hydrodynamic operation of the "Forest Flyer" type of explosive launching system for shock physics projectiles was investigated in detail using one and two dimensional continuum dynamics simulations. The simulations were numerically converged and insensitive to uncertainties in the material properties; they reproduced the speed of the projectile and the shape of its rear surface. The most commonly used variant, with an Al alloy case, was predicted to produce a slightly curved projectile, subjected to some shock heating and likely exhibiting some porosity from tensile damage. The curvature is caused by a shock reflected from the case; tensile damage is caused by the interaction of the Taylor wave pressure profile from the detonation wave with the free surface of the projectile. The simulations gave only an indication of tensile damage in the projectile, as damage is not understood well enough for predictions in this loading regime. The flatness can be improved by using a case of lower shock impedance, such as polymethyl methacrylate. High-impedance cases, including Al alloys but with denser materials improving the launching efficiency, can be used if designed according to the physics of oblique shock reflection, which indicates an appropriate case taper for any combination of explosive and case material. The tensile stress induced in the projectile depends on the relative thickness of the explosive, expansion gap, and projectile. The thinner the projectile with respect to the explosive, the smaller the tensile stress. Thus if the explosive is initiated with a plane wave lens, the tensile stress is lower than that for initiation with multiple detonators over a plane. The previous plane wave lens designs did, however, induce a tensile stress close to the spall strength of the projectile. The tensile stress can be reduced by changes in the component thicknesses. Experiments verifying the operation of explosively launched projectiles should attempt to measure

  19. On high explosive launching of projectiles for shock physics experiments.

    PubMed

    Swift, Damian C; Forest, Charles A; Clark, David A; Buttler, William T; Marr-Lyon, Mark; Rightley, Paul

    2007-06-01

    The hydrodynamic operation of the "Forest Flyer" type of explosive launching system for shock physics projectiles was investigated in detail using one and two dimensional continuum dynamics simulations. The simulations were numerically converged and insensitive to uncertainties in the material properties; they reproduced the speed of the projectile and the shape of its rear surface. The most commonly used variant, with an Al alloy case, was predicted to produce a slightly curved projectile, subjected to some shock heating and likely exhibiting some porosity from tensile damage. The curvature is caused by a shock reflected from the case; tensile damage is caused by the interaction of the Taylor wave pressure profile from the detonation wave with the free surface of the projectile. The simulations gave only an indication of tensile damage in the projectile, as damage is not understood well enough for predictions in this loading regime. The flatness can be improved by using a case of lower shock impedance, such as polymethyl methacrylate. High-impedance cases, including Al alloys but with denser materials improving the launching efficiency, can be used if designed according to the physics of oblique shock reflection, which indicates an appropriate case taper for any combination of explosive and case material. The tensile stress induced in the projectile depends on the relative thickness of the explosive, expansion gap, and projectile. The thinner the projectile with respect to the explosive, the smaller the tensile stress. Thus if the explosive is initiated with a plane wave lens, the tensile stress is lower than that for initiation with multiple detonators over a plane. The previous plane wave lens designs did, however, induce a tensile stress close to the spall strength of the projectile. The tensile stress can be reduced by changes in the component thicknesses. Experiments verifying the operation of explosively launched projectiles should attempt to measure

  20. Subnanosecond measurements of detonation fronts in solid high explosives

    NASA Astrophysics Data System (ADS)

    Sheffield, S. A.; Bloomquist, D. D.; Tarver, C. M.

    1984-04-01

    Detonation fronts in solid high explosives have been examined through measurements of particle velocity histories resulting from the interaction of a detonation wave with a thin metal foil backed by a water window. Using a high time resolution velocity-interferometer system, experiments were conducted on three explosives—a TATB (1,3,5-triamino-trinitrobenzene)-based explosive called PBX-9502, TNT (2,4,6-Trinitrotoluene), and CP (2-{5-cyanotetrazolato} pentaamminecobalt {III} perchlorate). In all cases, detonation-front rise times were found to be less than the 300 ps resolution of the interferometer system. The thermodynamic state in the front of the detonation wave was estimated to be near the unreacted state determined from an extrapolation of low-pressure unreacted Hugoniot data for both TNT and PBX-9502 explosives. Computer calculations based on an ignition and growth model of a Zeldovich-von Neumann-Doering (ZND) detonation wave show good agreement with the measurements. By using the unreacted Hugoniot and a JWL equation of state for the reaction products, we estimated the initial reaction rate in the high explosive after the detonation wave front interacted with the foil to be 40 μs-1 for CP, 60 μs-1 for TNT, and 80 μs-1 for PBX-9502. The shape of the profiles indicates the reaction rate decreases as reaction proceeds.

  1. Modeling Hot-Spot Contributions in Shocked High Explosives at the Mesoscale

    SciTech Connect

    Harrier, Danielle

    2015-08-12

    When looking at performance of high explosives, the defects within the explosive become very important. Plastic bonded explosives, or PBXs, contain voids of air and bonder between the particles of explosive material that aid in the ignition of the explosive. These voids collapse in high pressure shock conditions, which leads to the formation of hot spots. Hot spots are localized high temperature and high pressure regions that cause significant changes in the way the explosive material detonates. Previously hot spots have been overlooked with modeling, but now scientists are realizing their importance and new modeling systems that can accurately model hot spots are underway.

  2. Detonation initiation of heterogeneous melt-cast high explosives

    NASA Astrophysics Data System (ADS)

    Chuzeville, V.; Baudin, G.; Lefrançois, A.; Genetier, M.; Barbarin, Y.; Jacquet, L.; Lhopitault, J.-L.; Peix, J.; Boulanger, R.; Catoire, L.

    2017-01-01

    2,4,6-trinitrotoluene (TNT) is widely used in conventional and insensitive munitions as a fusible binder, commonly melt-cast with other explosives such as 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) or 3-nitro-1,2,4-triazol-one (NTO). In this paper, we study the shock-to-detonation transition phenomenon in two melt-cast high explosives (HE). We have performed plate impact tests on wedge samples to measure run-distance and time-to-detonation in order to establish the Pop-plot relation for several melt-cast HE. Highlighting the existence of the single curve buildup, we propose a two phase model based on a Zeldovich, Von-Neumann, Döring (ZND) approach where the deflagration fronts grow from the explosive grain boundaries. Knowing the grain size distribution, we calculate the deflagration velocities of the explosive charges as a function of shock pressure and explore the possible grain fragmentation.

  3. First-principles study of high explosive decomposition energetics

    SciTech Connect

    Wu, C J

    1998-08-21

    The mechanism of the gas phase unimolecular decomposition of hexahydro-1,3,5,- trinitro- 1,3,5,-triazine (RDX) has been investigated using first principles gradient corrected density functional theory. Our results show that the dominant reaction channel is the N-NO* bond rupture, which has a barrier of 34.2 kcal/mol at the B- PW9 l/cc-pVDZ level and is 18.3 kcal/mol lower than that of the concerted ring fission to three methylenenitramine molecules. In addition, we have carried out a systematic study of homolytic bond dissociation energies of 14 other high explosives at the B-PW91/D95V level. We find that the correlation between the weakest bond strength and high explosive sensitivity is strong

  4. Shock response of the commercial high explosive Detasheet

    NASA Astrophysics Data System (ADS)

    Asay, B. W.; Ramsay, J. B.; Anderson, M. U.; Graham, R. A.

    1994-12-01

    The mechanical and chemical response of the flexible commercial high explosive DetasheetR is studied under controlled impact and plane-wave, high explosive loading. Results on nonreactive material behavior, sound speed, shock-initiation sensitivity and detonation pressure are presented. The material is found to respond in a viscous manner reminiscent of viscoelastic response of polymeric materials. Time-resolved pressure and pressure-rate measurements with PVDF piezoelectric polymer gauges are presented along with Manganin pressure and plate-dent test measurements of detonation pressure. Detonation pressures of 18GPa are indicated. Pressure measurements show initiation of reaction between 3 and 8 mm for an impact stress of 3.1 GPa. Plane wave loading wedge tests show run distances to detonation consistent with the pressure measurements, and with behavior like that of XTX8003 (80 % PETN/20 % Sylgard 182R).

  5. Embedded fiber Bragg grating pressure measurement during thermal ignition of a high explosive

    SciTech Connect

    Rodriguez, George; Smilowitz, Laura Beth; Henson, Bryan Fayne

    2016-10-17

    A high-speed fiber Bragg grating based pressure-only measurement is reported for the high explosive PBXN-9 under thermal initiation conditions. During exothermic thermal runaway, an explosion rise time of 500 μs reaching a peak pressure of 660 MPa is measured. Lastly, the approach offers a direct measure pressure diagnostic useful for quantifying reaction violence for high explosive chemistry.

  6. Embedded fiber Bragg grating pressure measurement during thermal ignition of a high explosive

    NASA Astrophysics Data System (ADS)

    Rodriguez, G.; Smilowitz, L.; Henson, B. F.

    2016-10-01

    A high-speed fiber Bragg grating based pressure-only measurement is reported for the high explosive PBXN-9 under thermal initiation conditions. During exothermic thermal runaway, an explosion rise time of 500 μs reaching a peak pressure of 660 MPa is measured. The approach offers a direct measure pressure diagnostic useful for quantifying reaction violence for high explosive chemistry.

  7. Detonation Parameters for Australian High-Explosives Composition,

    DTIC Science & Technology

    1983-05-01

    components are mixed in different proportions in Australia from those used overseas. The choice of explosive depends on its sensitivity during manufacture...analysis are detonation velocity, pressure , temperature and energy output. Their experimental measurement is usually slow and potentially hazardous...compared. Theoretical estimates of detonation parameters are based on suitable high- pressure equations-of-state for the gaseous detonation products. The 0

  8. Study of high current commutation by explosive switch

    NASA Astrophysics Data System (ADS)

    Usuba, S.; Kakudate, Y.; Yoshida, M.; Fujiwara, S.; Miyamoto, M.; Morita, T.; Kubota, A.; den, M.

    1993-01-01

    The study presents the basic experimental data obtained with a large current opening switch for current commutation using explosives. It is shown that currents up to a maximum of 40 kA can be completely interrupted within 30 microsec. The mechanism of current interruption using a thin conductor plate and methods of measuring interrupting current with a pickup coil and taking photographs with a high-speed camera (one frame per microsec) are discussed.

  9. 60 kilograms high explosive containment with multi-diagnostic capability

    SciTech Connect

    Simmons, L F

    1998-09-17

    In anticipation of increasingly stringent environmental regulations, Lawrence Livermore National Laboratory (LLNL) proposes to construct a 60 kilogram (kg) firing chamber to provide blast-effects containment for most of its open-air, high explosives, firing operations. Even though these operations are within current environmental limits, containment of the blast effects and hazardous debris will further drastically reduce emissions to the environment and minimize the generated hazardous waste.

  10. Imaging High Speed Particles in Explosive Driven Blast Waves

    NASA Astrophysics Data System (ADS)

    Jenkins, Charles; Horie, Yasuyuki

    2009-06-01

    Researchers Mr. Charles Jenkins and Dr. Yasuyuki Horie at the High Explosive Research & Development (HERD) facility at Eglin AFB with sponsorship from DTRA has successfully imaged high speed explosively driven metallic particles. The process uses an adapted, commercially available Particle Image Velocimetry (PIV) instrument. Regional and particle flow vectors are determined from particle displacement between two images taken in rapid succession. The instrument consists of a 120 mJ, pulsed Nd:YAG laser, camera system, synchronizer, and proprietary imaging software. The new PIV capability provides the ability for scientists and engineers to map explosively driven metallic particles in a blast wave. Characteristics of particle motion, interaction and dispersion can be determined by this method, providing measurements of key parameters such as particle size, shape, velocity, and concentration. This new capability to image and track small (from a few microns to as large as several hundred microns) high-speed particles without direct intervention by physical means, ensures that the particles are unchanged in their environment and provides greater measurement accuracy of particle dynamics in very short time scales. The capability can also be used to map large areas (square feet) or to zoom down at higher magnifications to study particle features such as particle agglomeration.

  11. Characterization Of High Explosives Detonations Via Laser-Induced Plasmas

    SciTech Connect

    Villa-Aleman, E.

    2015-10-08

    One objective of the Department of Energy’s National Security Administration is to develop technologies that can help the United States government to detect foreign nuclear weapons development activities. The realm of high explosive (HE) experiments is one of the key areas to assess the nuclear ambitions of a country. SRNL has participated in the collection of particulates from HE experiments and characterized the material with the purpose to correlate particulate matter with HE. Since these field campaigns are expensive, on-demand simulated laboratory-scale explosion experiments are needed to further our knowledge of the chemistry and particle formation in the process. Our goal is to develop an experimental test bed in the laboratory to test measurement concepts and correlate particle formation processes with the observables from the detonation fireball. The final objective is to use this knowledge to tailor our experimental setups in future field campaigns. The test bed uses pulsed laser-induced plasmas to simulate micro-explosions, with the intent to study the temporal behavior of the fireball observed in field tests. During FY15, a plan was prepared and executed which assembled two laser ablation systems, procured materials for study, and tested a Step-Scan Fourier Transform Infrared Spectrometer (SS-FTIR). Designs for a shadowgraph system for shock wave analysis, design for a micro-particulate collector from ablated pulse were accomplished. A novel spectroscopic system was conceived and a prototype system built for acquisition of spectral/temporal characterization of a high speed event such as from a high explosive detonation. Experiments and analyses will continue into FY16.

  12. The confinement effect of inert materials on insensitive high explosives

    NASA Astrophysics Data System (ADS)

    Sun, Yutao; Yu, Ming

    2013-06-01

    The paper aims at investing the confinement effect of inert materials on insensitive high explosives by means of shock polar curve and phenomenological reaction model. The confinement types are categorized by the shock polar theory, which built on the leading shock wave based on the detonation ZND model. If the sonic velocity of the confinement material is less than the CJ velocity of an explosive, the shock polar theory can be utilized. In general, there are several types of interactions that give a ``match'' of the pressure and streamline-deflection across the interface between IHE and confinement material. A two-dimensional Lagrangian hydrodynamic method with three-term Lee-Tarver rate law is used to numerically simulate all types of confinement interactions. The important character of confinement material include: compressibility, thickness, the representative assembled layers, such as bakelite-iron and iron-beryllium. Supported by NSFC No.11101046.

  13. High explosive violent reaction (HEVR) from slow heating conditions

    SciTech Connect

    Vigil, A.S.

    1999-03-01

    The high explosives (HEs) developed and used at the Los Alamos National Laboratory are designed to be insensitive to impact and thermal insults under all but the most extreme conditions. Nevertheless, violent reactions do occasionally occur when HE is involved in an accident. The HE response is closely dependent on the type of external stimulus that initiates the reaction. For example, fast heating of conventional HE will probably result in fairly benign burning, while long-term, slow heating of conventional HE is more likely to produce an HEVR that will do much more damage to the immediate surroundings. An HEVR (High Explosive Violent Reaction) can be defined as the rapid release of energy from an explosive that ranges from slightly faster than a deflagration (very rapid burning) to a reaction that approaches a detonation. A number of thermal analyses have been done to determine slow heat/cook-off conditions that produce HE self-heating that can build up to a catastrophic runaway reaction. The author specifies the conditions that control reaction violence, describes experiments that produced an HEVR, describes analyses done to determine a heating rate threshold for HEVR, and lists possible HEVR situations.

  14. PINS Measurements and Simulations for Stand-Off Detection of High Explosives

    SciTech Connect

    E.H. Seabury

    2011-07-01

    There has been some interest in the ability of Idaho National Laboratory's (INL) Portable Isotopic Neutron Spectroscopy System's (PINS) ability to detect high explosives at a distance. In order to assess the system's ability to perform this task, laboratory experiments on simulated or mock explosives and Monte Carlo simulations using MCNP on both mock and real explosives have been performed. The simulations and experiments on mock explosives have essentially identical configurations, allowing the models to be confirmed with experiment. This provides greater confidence in the simulations on real explosives without the need for experiment on live explosives.

  15. High-speed imaging of explosive eruptions: applications and perspectives

    NASA Astrophysics Data System (ADS)

    Taddeucci, Jacopo; Scarlato, Piergiorgio; Gaudin, Damien; Capponi, Antonio; Alatorre-Ibarguengoitia, Miguel-Angel; Moroni, Monica

    2013-04-01

    Explosive eruptions, being by definition highly dynamic over short time scales, necessarily call for observational systems capable of relatively high sampling rates. "Traditional" tools, like as seismic and acoustic networks, have recently been joined by Doppler radar and electric sensors. Recent developments in high-speed camera systems now allow direct visual information of eruptions to be obtained with a spatial and temporal resolution suitable for the analysis of several key eruption processes. Here we summarize the methods employed to gather and process high-speed videos of explosive eruptions, and provide an overview of the several applications of these new type of data in understanding different aspects of explosive volcanism. Our most recent set up for high-speed imaging of explosive eruptions (FAMoUS - FAst, MUltiparametric Set-up,) includes: 1) a monochrome high speed camera, capable of 500 frames per second (fps) at high-definition (1280x1024 pixel) resolution and up to 200000 fps at reduced resolution; 2) a thermal camera capable of 50-200 fps at 480-120x640 pixel resolution; and 3) two acoustic to infrasonic sensors. All instruments are time-synchronized via a data logging system, a hand- or software-operated trigger, and via GPS, allowing signals from other instruments or networks to be directly recorded by the same logging unit or to be readily synchronized for comparison. FAMoUS weights less than 20 kg, easily fits into four, hand-luggage-sized backpacks, and can be deployed in less than 20' (and removed in less than 2', if needed). So far, explosive eruptions have been recorded in high-speed at several active volcanoes, including Fuego and Santiaguito (Guatemala), Stromboli (Italy), Yasur (Vanuatu), and Eyjafiallajokull (Iceland). Image processing and analysis from these eruptions helped illuminate several eruptive processes, including: 1) Pyroclasts ejection. High-speed videos reveal multiple, discrete ejection pulses within a single Strombolian

  16. Research and Development of High-performance Explosives.

    PubMed

    Cornell, Rodger; Wrobel, Erik; Anderson, Paul E

    2016-02-20

    Developmental testing of high explosives for military applications involves small-scale formulation, safety testing, and finally detonation performance tests to verify theoretical calculations. small-scale For newly developed formulations, the process begins with small-scale mixes, thermal testing, and impact and friction sensitivity. Only then do subsequent larger scale formulations proceed to detonation testing, which will be covered in this paper. Recent advances in characterization techniques have led to unparalleled precision in the characterization of early-time evolution of detonations. The new technique of photo-Doppler velocimetry (PDV) for the measurement of detonation pressure and velocity will be shared and compared with traditional fiber-optic detonation velocity and plate-dent calculation of detonation pressure. In particular, the role of aluminum in explosive formulations will be discussed. Recent developments led to the development of explosive formulations that result in reaction of aluminum very early in the detonation product expansion. This enhanced reaction leads to changes in the detonation velocity and pressure due to reaction of the aluminum with oxygen in the expanding gas products.

  17. Research and Development of High-performance Explosives

    PubMed Central

    Cornell, Rodger; Wrobel, Erik; Anderson, Paul E.

    2016-01-01

    Developmental testing of high explosives for military applications involves small-scale formulation, safety testing, and finally detonation performance tests to verify theoretical calculations. small-scale For newly developed formulations, the process begins with small-scale mixes, thermal testing, and impact and friction sensitivity. Only then do subsequent larger scale formulations proceed to detonation testing, which will be covered in this paper. Recent advances in characterization techniques have led to unparalleled precision in the characterization of early-time evolution of detonations. The new technique of photo-Doppler velocimetry (PDV) for the measurement of detonation pressure and velocity will be shared and compared with traditional fiber-optic detonation velocity and plate-dent calculation of detonation pressure. In particular, the role of aluminum in explosive formulations will be discussed. Recent developments led to the development of explosive formulations that result in reaction of aluminum very early in the detonation product expansion. This enhanced reaction leads to changes in the detonation velocity and pressure due to reaction of the aluminum with oxygen in the expanding gas products. PMID:26966969

  18. The confinement effect of inert materials on insensitive high explosives

    NASA Astrophysics Data System (ADS)

    Sun, Yutao; Yu, Ming; Tang, Li

    2014-03-01

    The paper aims at investing the confinement effect of inert materials on insensitive high explosives by means of shock polar curve and phenomenological reaction model. The confinement types are categorized by the shock polar theory, which built on the leading shock wave based on the detonation ZND model. If the sonic velocity of the confinement material is less than the CJ velocity of an explosive, the shock polar theory can be utilized. In general, there are several types of interactions that give a ?match? of the pressure and streamline-deflection across the interface between IHE and confinement material. A two-dimensional Lagrangian hydrodynamic method with three-term Lee-Tarver rate law is used to numerically simulate all types of confinement interactions. The important character of confinement material include: compressibility, thickness, the representative assembled layers, such as bakelite-iron and iron-beryllium. An improved detonation model is established to simulate the pre-compression effect on unreact explosive. Supported by NSFC No.11101046.

  19. Mechanical Behavior of TNAZ/CAB Explosives during High Acceleration

    NASA Astrophysics Data System (ADS)

    Lanzerotti, Y.; Capellos, C.; Travers, B.; Sharma, J.

    2004-07-01

    The mechanical behavior of melt-cast TNAZ/CAB (1,3,3-trinitroazetidine/cellulose acetate butyrate) explosives subjected to high acceleration has been studied in an ultracentrifuge at -10°C and 25°C. Melt-cast TNAZ/CAB was studied as a function of the percentage of the composition of CAB at -10°C and 25°C. The percentage of CAB in the samples varied from 0.5% to 3%. Failure occurs when the shear or tensile strength of the explosive is exceeded. The fracture acceleration of melt-cast TNAZ/CAB increases with the percentage of CAB in the explosive at both temperatures studied, -10°C and 25°C. While there is some variation among samples, it is found that the fracture acceleration of melt-cast 99%/1% TNAZ/CAB and melt-cast 99.5%/0.5% TNAZ/CAB at -10°C is less than that at 25°C.

  20. Model of non-ideal detonation of condensed high explosives

    NASA Astrophysics Data System (ADS)

    Smirnov, E. B.; Kostitsin, O. V.; Koval, A. V.; Akhlyustin, I. A.

    2016-11-01

    The Zeldovich-Neumann-Doering theory of ideal detonation allows one to describe adequately the detonation of charges with near-critical diameter. For smaller diameters, detonation velocity can differ significantly from an ideal value expected based on equilibrium chemical thermodynamics. This difference is quite evident when using non-ideal explosives; in certain cases, this value can be up to one third of ideal detonation velocity. Numerical simulation of these systems is a very labor-consuming process because one needs to compute the states inside the chemical reaction zone, as well as to obtain data on the equation of state of high-explosive detonation products mixture and on the velocity of chemical reaction; however, these characteristics are poorly studied today. For practical purposes, one can use the detonation shock dynamics model based on interrelation between local velocity of the front and its local curvature. This interrelation depends on both the equation of state of explosion products, and the reaction velocity; but the explicit definition of these characteristics is not needed. In this paper, experimental results are analyzed. They demonstrate interrelation between the local curvature of detonation front and the detonation velocity. Equation of detonation front shape is found. This equation allows us to predict detonation velocity and shape of detonation wave front in arbitrary geometry by integrating ordinary differential equation for the front shape with a boundary condition at the charge edge. The results confirm that the model of detonation shock dynamics can be used to describe detonation processes in non-ideal explosives.

  1. A case of death from the explosion of a 66mm M72 High Explosive Anti-Tank rocket.

    PubMed

    Ihama, Yoko; Miyazaki, Tetsuji; Fuke, Chiaki; Taira, Zenshin

    2008-07-01

    A 53-year-old male died from an explosion of a 66 mm M72 High Explosive Anti-Tank (HEAT) rocket. He had collected various cast-off military weapons and was selling them. There were numerous explosive injuries on the anterior side of the body, thus especially bilateral hands, left toe and right knee were severely crushed and fractured. The location and severity of the injuries suggest that he was down on his left knee and was manipulating the weapon with both hands at the moment of detonation. We consider that 66 mm M72 HEAT rocket accidentally detonated during his handling. Very rarely are civilians killed by a military weapon, except during wartime. Appropriate investigation of various explosive injuries provide not only evidence of the cause of death, but also the position and posture of the body.

  2. Toxicological study of the high explosive formulation X-0298

    SciTech Connect

    London, J.E.; Smith, D.M.

    1983-01-01

    The acute oral LD/sub 50/ values for the high-explosive formulation X-0298 for mice and rats is greater than 5 g/kg. According to classical guidelines, the mixture would be considered only slightly or practically nontoxic in both species. Skin application studies in the rabbit with X-0298 demonstrated that it was cutaneously nonirritating. This material was also nonirritating in rabbit eye application studies. The sensitization study in the guinea pig did not show X-0298 to be deleterious in this regard.

  3. Shock initiation of explosives: High temperature hot spots explained

    NASA Astrophysics Data System (ADS)

    Bassett, Will P.; Johnson, Belinda P.; Neelakantan, Nitin K.; Suslick, Kenneth S.; Dlott, Dana D.

    2017-08-01

    We investigated the shock initiation of energetic materials with a tabletop apparatus that uses km s-1 laser-driven flyer plates to initiate tiny explosive charges and obtains complete temperature histories with a high dynamic range. By comparing various microstructured formulations, including a pentaerythritol tetranitrate (PETN) based plastic explosive (PBX) denoted XTX-8003, we determined that micron-scale pores were needed to create high hot spot temperatures. In charges where micropores (i.e., micron-sized pores) were present, a hot spot temperature of 6000 K was observed; when the micropores were pre-compressed to nm scale, however, the hot spot temperature dropped to ˜4000 K. By comparing XTX-8003 with an analog that replaced PETN by nonvolatile silica, we showed that the high temperatures require gas in the pores, that the high temperatures were created by adiabatic gas compression, and that the temperatures observed can be controlled by the choice of ambient gases. The hot spots persist in shock-compressed PBXs even in vacuum because the initially empty pores became filled with gas created in-situ by shock-induced chemical decomposition.

  4. Conversion of high explosive chemical energy into energy of powerful nanosecond high-current pulses

    NASA Astrophysics Data System (ADS)

    Gorbachev, K. V.; Mikhaylov, V. M.; Nesterov, E. V.; Stroganov, V. A.; Chernykh, E. V.

    2015-01-01

    This study is a contribution into the development of physicotechnical foundations for generation of powerful nanosecond high-current pulses on the basis of explosively driven magnetic flux compression generators. This problem is solved by using inductive storage of energy for matching comparatively low-voltage explosively driven magnetic flux compression generators and high-impedance loads; short forming lines and vacuum diodes. Experimental data of charging of forming lines are given.

  5. Predicting High Explosive Detonation Velocities from Their Composition and Structure

    DTIC Science & Technology

    1978-09-01

    for a gamut of ideal explosives. The explosives ranged from nitroaromatics, cyclic and linear nitramines, nitrate esters and nitro-nitrato...structure is postulated for a gamut of explosives. Since detonation velocity, DQ, is density dependent, the linear regression plot. Figure 1, of the

  6. A second survey of high explosives traces in public places.

    PubMed

    Cullum, Hazel E; McGavigan, Claire; Uttley, Claire Z; Stroud, Mark A M; Warren, Derek C

    2004-07-01

    This survey was carried out as a follow-up to a 1994 survey carried out by this laboratory (1) in order to determine the background levels of explosives traces in public places. The first survey concentrated on transport areas and police stations in and around London. This second study examines levels in four of the United Kingdom's major cities: Birmingham, Cardiff, Glasgow, and Manchester. Samples were taken at various transport sites and from hotels, private houses, private vehicles, and clothing. The survey showed that traces of the high explosives nitroglycerine (NG), trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), and cyclotrimethylene trinitramine (RDX) are rare within the general public environment. Only one low-level trace of RDX was detected. NG, possibly associated with the use of firearms, was detected at low levels in two samples and 2,4-DNT was detected in a separate sample. No PETN was detected in any of the samples. The results of the survey indicate that it is unlikely that persons visiting public areas could become significantly contaminated with explosives. The analytical procedures employed would also have detected ethylene glycol dinitrate (EGDN) if present at levels greater than 2 ng, nitrobenzene (NB) if present at levels greater than 50 ng, mononitrotoluenes if present at levels greater than 50 ng, and the other common isomers of dinitrotoluene if these had been present at levels in excess of 10 ng. None of these were detected. The relatively high volatility of EGDN, NB, and the mononitrotoluenes would, however, cause traces of these compounds to disperse rapidly. A proportion of the samples (approximately 7%) were analyzed for the presence of HMX. No HMX was detected.

  7. Photoactive High Explosives: Substituents Effects on Tetrazine Photochemistry and Photophysics

    SciTech Connect

    McGrane, Shawn David; Bolme, Cynthia Anne; Greenfield, Margo Torello; Chavez, David E.; Hanson, Susan Kloek; Scharff, Robert Jason

    2016-01-21

    High explosives that are photoactive, i.e., can be initiated with light, offer significant advantages in reduced potential for accidental electrical initiation. In this study, we examined a series of structurally related tetrazine based photoactive high explosive materials to detail their photochemical and photophysical properties. Using photobleaching infrared absorption, we determined quantum yields of photochemistry for nanosecond pulsed excitation at 355 and 532 nm. Changes in mass spectrometry during laser irradiation in vacuum measured the evolution of gaseous products. Fluorescence spectra, quantum yields, and lifetimes were measured to observe radiative channels of energy decay that compete with photochemistry. For the 6 materials studied, quantum yields of photochemistry ranged from <10–5 to 0.03 and quantum yield of fluorescence ranged from <10–3 to 0.33. In all cases, the photoexcitation nonradiatively relaxed primarily to heat, appropriate for supporting photothermal initiation processes. Lastly, the photochemistry observed was dominated by ring scission of the tetrazine, but there was evidence of more extensive multistep reactions as well.

  8. Photoactive High Explosives: Substituents Effects on Tetrazine Photochemistry and Photophysics

    DOE PAGES

    McGrane, Shawn David; Bolme, Cynthia Anne; Greenfield, Margo Torello; ...

    2016-01-21

    High explosives that are photoactive, i.e., can be initiated with light, offer significant advantages in reduced potential for accidental electrical initiation. In this study, we examined a series of structurally related tetrazine based photoactive high explosive materials to detail their photochemical and photophysical properties. Using photobleaching infrared absorption, we determined quantum yields of photochemistry for nanosecond pulsed excitation at 355 and 532 nm. Changes in mass spectrometry during laser irradiation in vacuum measured the evolution of gaseous products. Fluorescence spectra, quantum yields, and lifetimes were measured to observe radiative channels of energy decay that compete with photochemistry. For the 6more » materials studied, quantum yields of photochemistry ranged from <10–5 to 0.03 and quantum yield of fluorescence ranged from <10–3 to 0.33. In all cases, the photoexcitation nonradiatively relaxed primarily to heat, appropriate for supporting photothermal initiation processes. Lastly, the photochemistry observed was dominated by ring scission of the tetrazine, but there was evidence of more extensive multistep reactions as well.« less

  9. An explosively driven high-power microwave pulsed power system

    NASA Astrophysics Data System (ADS)

    Elsayed, M. A.; Neuber, A. A.; Dickens, J. C.; Walter, J. W.; Kristiansen, M.; Altgilbers, L. L.

    2012-02-01

    The increased popularity of high power microwave systems and the various sources to drive them is the motivation behind the work to be presented. A stand-alone, self-contained explosively driven high power microwave pulsed power system has been designed, built, and tested at Texas Tech University's Center for Pulsed Power and Power Electronics. The system integrates four different sub-units that are composed of a battery driven prime power source utilizing capacitive energy storage, a dual stage helical flux compression generator as the main energy amplification device, an integrated power conditioning system with inductive energy storage including a fast opening electro-explosive switch, and a triode reflex geometry virtual cathode oscillator as the microwave radiating source. This system has displayed a measured electrical source power level of over 5 GW and peak radiated microwaves of about 200 MW. It is contained within a 15 cm diameter housing and measures 2 m in length, giving a housing volume of slightly less than 39 l. The system and its sub-components have been extensively studied, both as integrated and individual units, to further expand on components behavior and operation physics. This report will serve as a detailed design overview of each of the four subcomponents and provide detailed analysis of the overall system performance and benchmarks.

  10. Field-based high-speed imaging of explosive eruptions

    NASA Astrophysics Data System (ADS)

    Taddeucci, J.; Scarlato, P.; Freda, C.; Moroni, M.

    2012-12-01

    Explosive eruptions involve, by definition, physical processes that are highly dynamic over short time scales. Capturing and parameterizing such processes is a major task in eruption understanding and forecasting, and a task that necessarily requires observational systems capable of high sampling rates. Seismic and acoustic networks are a prime tool for high-frequency observation of eruption, recently joined by Doppler radar and electric sensors. In comparison with the above monitoring systems, imaging techniques provide more complete and direct information of surface processes, but usually at a lower sampling rate. However, recent developments in high-speed imaging systems now allow such information to be obtained with a spatial and temporal resolution suitable for the analysis of several key eruption processes. Our most recent set up for high-speed imaging of explosive eruptions (FAMoUS - FAst, MUltiparametric Set-up,) includes: 1) a monochrome high speed camera, capable of 500 frames per second (fps) at high-definition (1280x1024 pixel) resolution and up to 200000 fps at reduced resolution; 2) a thermal camera capable of 50-200 fps at 480-120x640 pixel resolution; and 3) two acoustic to infrasonic sensors. All instruments are time-synchronized via a data logging system, a hand- or software-operated trigger, and via GPS, allowing signals from other instruments or networks to be directly recorded by the same logging unit or to be readily synchronized for comparison. FAMoUS weights less than 20 kg, easily fits into four, hand-luggage-sized backpacks, and can be deployed in less than 20' (and removed in less than 2', if needed). So far, explosive eruptions have been recorded in high-speed at several active volcanoes, including Fuego and Santiaguito (Guatemala), Stromboli (Italy), Yasur (Vanuatu), and Eyjafiallajokull (Iceland). Image processing and analysis from these eruptions helped illuminate several eruptive processes, including: 1) Pyroclasts ejection. High

  11. High Explosive Corner Turning Performance and the LANL Mushroom Test

    NASA Astrophysics Data System (ADS)

    Hill, L. G.; Seitz, W. L.

    1997-07-01

    The LANL Mushroom Test is a simple, precision experiment designed to characterize the corner turning performance of the newer, less sensitive, solid high-explosive booster materials. The test is named for its distinctive geometry--- a 25.4-mm diameter pressed hemispherical ``cap'' of test material, initiated by a 6-mm diameter ``stem'' of the RDX-based explosive PBX9407. This stem diameter was chosen because it produces marginal wave spread in materials of interest, thereby making the test quite sensitive to changes in composition, particle size, and pressed density. Detonation breakout from the hemispherical surface is observed with a streak camera, both by direct observation and via two 45-degree mirrors. The processed data is a composite plot of breakout time vs. polar angle from the three views. The temporal data may be processed in various ways to quantify corner turning performance, and several possible figures-of-merit are discussed and compared. For each material a series of six to eight tests is performed on samples having densities close to, and on either side of, the nominal density. The figures-of-merit are then plotted and fit as a function of density. Data for ultrafine TATB and PBX9504 (70 wt.% TATB, 25 wt.% PETN, 5 wt.% Kel-F) are presented as examples.

  12. Laser impingement on bare and encased high explosives: safety limits

    SciTech Connect

    Roeske, F

    1999-03-15

    During the course of experiments involving high explosives, (HE), alignment lasers are often employed where the laser beam impinges upon a metal encased HE sample or on the bare HE itself during manned operations. While most alignment lasers are of low enough power so as not to be of concern, safety questions arise when considering the maximum credible power output of the laser in a failure mode, or when multiple laser spots are focused onto the experiment simultaneously. Safety questions also arise when the focused laser spot size becomes very small, on the order of 100 {micro}m or less. This paper addresses these concerns by describing a methodology for determining safety margins for laser impingement on metal encased HE as well as one for bare HE. A variety of explosives encased in Al, Cu, Ta and stainless steel were tested using the first of these techniques. Additional experiments were performed using the second method where the laser beam was focused directly on eight different samples of pressed-powder HE.

  13. High Resolution Digital Elevation Models of Pristine Explosion Craters

    NASA Technical Reports Server (NTRS)

    Farr, T. G.; Krabill, W.; Garvin, J. B.

    2004-01-01

    In order to effectively capture a realistic terrain applicable to studies of cratering processes and landing hazards on Mars, we have obtained high resolution digital elevation models of several pristine explosion craters at the Nevada Test Site. We used the Airborne Terrain Mapper (ATM), operated by NASA's Wallops Flight Facility to obtain DEMs with 1 m spacing and 10 cm vertical errors of 4 main craters and many other craters and collapse pits. The main craters that were mapped are Sedan, Scooter, Schooner, and Danny Boy. The 370 m diameter Sedan crater, located on Yucca Flat, is the largest and freshest explosion crater on Earth that was formed under conditions similar to hypervelocity impact cratering. As such, it is effectively pristine, having been formed in 1962 as a result of a controlled detonation of a 100 kiloton thermonuclear device, buried at the appropriate equivalent depth of burst required to make a simple crater. Sedan was formed in alluvium of mixed lithology and subsequently studied using a variety of field-based methods. Nearby secondary craters were also formed at the time and were also mapped by ATM. Adjacent to Sedan and also in alluvium is Scooter, about 90 m in diameter and formed by a high-explosive event. Schooner (240 m) and Danny Boy (80 m) craters were also important targets for ATM as they were excavated in hard basalt and therefore have much rougher ejecta. This will allow study of ejecta patterns in hard rock as well as engineering tests of crater and rock avoidance and rover trafficability. In addition to the high resolution DEMs, crater geometric characteristics, RMS roughness maps, and other higher-order derived data products will be generated using these data. These will provide constraints for models of landing hazards on Mars and for rover trafficability. Other planned studies will include ejecta size-frequency distribution at the resolution of the DEM and at finer resolution through air photography and field measurements

  14. High Resolution Digital Elevation Models of Pristine Explosion Craters

    NASA Technical Reports Server (NTRS)

    Farr, T. G.; Krabill, W.; Garvin, J. B.

    2004-01-01

    In order to effectively capture a realistic terrain applicable to studies of cratering processes and landing hazards on Mars, we have obtained high resolution digital elevation models of several pristine explosion craters at the Nevada Test Site. We used the Airborne Terrain Mapper (ATM), operated by NASA's Wallops Flight Facility to obtain DEMs with 1 m spacing and 10 cm vertical errors of 4 main craters and many other craters and collapse pits. The main craters that were mapped are Sedan, Scooter, Schooner, and Danny Boy. The 370 m diameter Sedan crater, located on Yucca Flat, is the largest and freshest explosion crater on Earth that was formed under conditions similar to hypervelocity impact cratering. As such, it is effectively pristine, having been formed in 1962 as a result of a controlled detonation of a 100 kiloton thermonuclear device, buried at the appropriate equivalent depth of burst required to make a simple crater. Sedan was formed in alluvium of mixed lithology and subsequently studied using a variety of field-based methods. Nearby secondary craters were also formed at the time and were also mapped by ATM. Adjacent to Sedan and also in alluvium is Scooter, about 90 m in diameter and formed by a high-explosive event. Schooner (240 m) and Danny Boy (80 m) craters were also important targets for ATM as they were excavated in hard basalt and therefore have much rougher ejecta. This will allow study of ejecta patterns in hard rock as well as engineering tests of crater and rock avoidance and rover trafficability. In addition to the high resolution DEMs, crater geometric characteristics, RMS roughness maps, and other higher-order derived data products will be generated using these data. These will provide constraints for models of landing hazards on Mars and for rover trafficability. Other planned studies will include ejecta size-frequency distribution at the resolution of the DEM and at finer resolution through air photography and field measurements

  15. Recent Approaches to the Synthesis of High Explosive and Energetic Materials: A Review,

    DTIC Science & Technology

    1982-04-01

    AD-Ri22 951 RECENT APPROACHES TO THE SYNTHESIS OF NIGH EXPLOSIVE i AND ENERGETIC MATERIALS: A REYIE&I(U) MATERIALS RESEARCH LABS ASCOT VALE...ORGANISATION - MATERIALS RESEARCH LABORATORIES MELBOURNE, VICTORIA REPORT MRL..-R50 - RECENT APPROACHES TO THE SYNTHESIS OF HIGH EXPLOSIVE AND ENERGETIC...1982 DEPARTMENT OF DEFENCE MATERIALS RESEARCH LABORATORIES REPORT MRL-R-850 RECENT APPROACHES TO THE SYNTHESIS OF HIGH EXPLOSIVE AND ENERGETIC MATERIALS

  16. Collisional Effects in Simulations of High Altitude Nuclear Explosions

    NASA Astrophysics Data System (ADS)

    Islam, Tanim

    2013-10-01

    The simulation of the later-time (> 1 second) debris dynamics of a high altitude nuclear explosion (HANE) require, at a minimum, an understanding of the interaction of the ionized blast material with the relatively collisional upper ionosphere and lower exosphere (<= 200 km). At these altitudes, the collisional mean free path of ionized atmospheric particles may become smaller than the length scale of the diamagnetic bubble. Here we report on the local dynamics about the debris/air interface for Starfish Prime like, and lower energy, HANEs at altitudes in which collisionality becomes important. We model the debris dynamics with the hybrid plasma simulation code KIM3D, and use a standard Miller-Combi particle pairing algorithm to model particle collisions. We demonstrate new dynamics associated with finite collisionality in mildly collisional HANEs.

  17. Moderate Velocity Ball Impact of a Mock High-Explosive

    SciTech Connect

    Furmanski, Jevan; Rae, Philip; Clements, Bradford E.

    2012-06-05

    Modeling of thermal and mechanical events in high-explosive materials is complicated by the composite nature of the material, which experiences viscoelastic and plastic deformations and sustains damage in the form of microcracks that can dominate its overall behavior. A mechanical event of interest is projectile interaction with the material, which leads to extreme local deformation and adiabatic heating, which can potentially lead to adverse outcomes in an energetic material. Simulations of such an event predicted large local temperature rises near the path of a spherical projectile, but these were experimentally unconfirmed and hence potentially non-physical. This work concerns the experimental verification of local temperatures both at the surface and in the wake of a spherical projectile penetrating a mock (unreactive) high-explosive at {approx}700 m/s. Fast response thermocouples were embedded radially in a mid-plane of a cylindrical target, which was bonded around the thermocouples with epoxy and recorded by an oscilloscope through a low-pass filter with a bandwidth of 500 Hz. A peak temperature rise of 70 K was measured both at the equator of the projectile and in its wake, in good agreement with the temperature predicted in the minimally distorted elements at those locations by a finite element model in ABAQUS employing the ViscoSCRAM constitutive model. Further work is needed to elucidate the extreme temperature rises in material undergoing crushing or fragmentation, which is difficult to predict with meshed finite element methods due to element distortion, and also challenging to quantify experimentally.

  18. Infrared spectrometry and radiometry of high-explosive detonations: the Los Alamos experiments

    SciTech Connect

    Rogers, E H; Williams, R L; Frazier, E N; Stone, D K; Herr, K C; Young, R M; Robbins, R G

    1982-11-01

    The purpose of these experiments was to determine whether the infrared spectra of high-explosive detonations can be used to infer the type of explosive material and/or the containment material employed. Infrared spectra and radiometric traces were measured during a test series of twenty-three detonations; some were contained and some uncontained. A variety of high-explosive materials and containment materials were included. The explosive charge was typically about 175 g. Infrared spectra were taken at the rate of 250 spectra/sec. This rate was too slow to characterize the very early gas expansion or burn pase of these explosions. The infrared spectra of the delayed or afterburn phase of these explosions often displayed molecular emission and absorption features. Absorption by NH/sub 3/ was observed when C-4 was the high-explosive material, and not observed for any other material. Emissions from H/sub 2/O and CO/sub 2/ were observed part of the time. Their occurence does not seem to be correlated with the type of containment or type of high-explosive material, or peak temperature reached in the afterburn. From the radiometric traces, one concludes that the relative peak radiance from the burn and afterburn phases depend strongly on the type of high-explosive material. For similar devices the burn phase is consistent from shot to shot, whereas the afterburn is very inconsistent. The answer to the question whether infrared spectra of high-explosive detonations can be used to infer the type of explosive material and/or the containment material must await spectral observations of the burn phase. We now believe that spectra of the burn phase are likely to be the ones most useful in identifying the high-explosive or containment material.

  19. Mechanisms of shock-induced reactions in high explosives

    NASA Astrophysics Data System (ADS)

    Kay, Jeffrey J.

    2017-01-01

    Understanding the mechanisms by which shock waves initiate chemical reactions in explosives is key to understanding their unique and defining property: the ability to undergo rapid explosive decomposition in response to mechanical stimulus. Although shock-induced reactions in explosives have been studied experimentally and computationally for decades, the nature of even the first chemical reactions that occur in response to shock remain elusive. To predictively understand how explosives respond to shock, the detailed sequence of events that occurs - mechanical deformation, energy transfer, bond breakage, and first chemical reactions - must be understood at the quantum-mechanical level. This paper reviews recent work in this field and ongoing experimental and theoretical work at Sandia National Laboratories in this important area of explosive science.

  20. DMSO/base hydrolysis method for the disposal of high explosives and related energetic materials

    DOEpatents

    Desmare, Gabriel W.; Cates, Dillard M.

    2002-05-14

    High explosives and related energetic materials are treated via a DMSO/base hydrolysis method which renders them non-explosive and/or non-energetic. For example, high explosives such as 1,3,5,7-tetraaza-1,3,5,7-tetranitrocyclooctane (HMX), 1,3,5-triaza-1,3,5-trinitrocyclohexane (RDX), 2,4,6-trinitrotoluene (TNT), or mixtures thereof, may be dissolved in a polar, aprotic solvent and subsequently hydrolyzed by adding the explosive-containing solution to concentrated aqueous base. Major hydrolysis products typically include nitrite, formate, and nitrous oxide.

  1. Computer simulation of metal wire explosion under high rate heating

    NASA Astrophysics Data System (ADS)

    Zolnikov, K. P.; Kryzhevich, D. S.; Korchuganov, A. V.

    2017-05-01

    Synchronous electric explosion of metal wires and synthesis of bicomponent nanoparticles were investigated on the base of molecular dynamics method. Copper and nickel nanosized crystallites of cylindrical shape were chosen as conductors for explosion. The embedded atom approximation was used for calculation of the interatomic interactions. The agglomeration process after explosion metal wires was the main mechanism for particle synthesis. The distribution of chemical elements was non-uniform over the cross section of the bicomponent particles. The copper concentration in the surface region was higher than in the bulk of the synthesized particle. By varying the loading parameters (heating temperature, the distance between the wires) one can control the size and internal structure of the synthesized bicomponent nanoparticles. The obtained results showed that the method of molecular dynamics can be effectively used to determine the optimal technological mode of nanoparticle synthesis on the base of electric explosion of metal wires.

  2. Recent Advances in the Synthesis of High Explosive Materials

    DTIC Science & Technology

    2016-05-09

    area, the development of explosive materials with higher thermal stability and secondary explosive-based formulations that have a low sensitivity to...substances on an international scale. It is classified as a toxic pollutant in the USA, and efforts have been underway for decades to remove lead from...on an international scale. It is classified as a toxic pollutant in the USA, and efforts have been underway for decades to remove lead from Federal

  3. Systematic approach to verification and validation: High explosive burn models

    SciTech Connect

    Menikoff, Ralph; Scovel, Christina A.

    2012-04-16

    Most material models used in numerical simulations are based on heuristics and empirically calibrated to experimental data. For a specific model, key questions are determining its domain of applicability and assessing its relative merits compared to other models. Answering these questions should be a part of model verification and validation (V and V). Here, we focus on V and V of high explosive models. Typically, model developers implemented their model in their own hydro code and use different sets of experiments to calibrate model parameters. Rarely can one find in the literature simulation results for different models of the same experiment. Consequently, it is difficult to assess objectively the relative merits of different models. This situation results in part from the fact that experimental data is scattered through the literature (articles in journals and conference proceedings) and that the printed literature does not allow the reader to obtain data from a figure in electronic form needed to make detailed comparisons among experiments and simulations. In addition, it is very time consuming to set up and run simulations to compare different models over sufficiently many experiments to cover the range of phenomena of interest. The first difficulty could be overcome if the research community were to support an online web based database. The second difficulty can be greatly reduced by automating procedures to set up and run simulations of similar types of experiments. Moreover, automated testing would be greatly facilitated if the data files obtained from a database were in a standard format that contained key experimental parameters as meta-data in a header to the data file. To illustrate our approach to V and V, we have developed a high explosive database (HED) at LANL. It now contains a large number of shock initiation experiments. Utilizing the header information in a data file from HED, we have written scripts to generate an input file for a hydro code

  4. Experimental Comparison of Shock and Bubble Heave Energies from Underwater Explosion of Ideal HE and Explosive Composite Mixtures Highly Enriched with Aluminum

    NASA Astrophysics Data System (ADS)

    Komissarov, P. V.; Borisov, A. A.; Sokolov, G. N.; Lavrov, V. V.

    Experimental data on shock wave and bubble heave energies at underwater explosion of charges based on highly enriched with aluminium explosive mixtures are reported. Al/O ratios of the mixtures used are varied from 1.31 to 2.36. Al-rich charges up to 30 g were exploded in basin of 2 m in diameter and 5 m in depth. As a result, Al-rich mixtures used are demonstrates overall specific energies of underwater explosion up to twice higher than conventional high explosives.

  5. High-speed multi-frame laser Schlieren for visualization of explosive events

    NASA Astrophysics Data System (ADS)

    Clarke, S. A.; Murphy, M. J.; Landon, C. D.; Mason, T. A.; Adrian, R. J.; Akinci, A. A.; Martinez, M. E.; Thomas, K. A.

    2007-09-01

    High-Speed Multi-Frame Laser Schlieren is used for visualization of a range of explosive and non-explosive events. Schlieren is a well-known technique for visualizing shock phenomena in transparent media. Laser backlighting and a framing camera allow for Schlieren images with very short (down to 5 ns) exposure times, band pass filtering to block out explosive self-light, and 14 frames of a single explosive event. This diagnostic has been applied to several explosive initiation events, such as exploding bridgewires (EBW), Exploding Foil Initiators (EFI) (or slappers), Direct Optical Initiation (DOI), and ElectroStatic Discharge (ESD). Additionally, a series of tests have been performed on "cut-back" detonators with varying initial pressing (IP) heights. We have also used this Diagnostic to visualize a range of EBW, EFI, and DOI full-up detonators. The setup has also been used to visualize a range of other explosive events, such as explosively driven metal shock experiments and explosively driven microjets. Future applications to other explosive events such as boosters and IHE booster evaluation will be discussed. Finite element codes (EPIC, CTH) have been used to analyze the schlieren images to determine likely boundary or initial conditions to determine the temporal-spatial pressure profile across the output face of the detonator. These experiments are part of a phased plan to understand the evolution of detonation in a detonator from initiation shock through run to detonation to full detonation to transition to booster and booster detonation.

  6. Biodegradation of the High Explosive Hexanitrohexaazaiso-wurtzitane (CL-20)

    PubMed Central

    Karakaya, Pelin; Christodoulatos, Christos; Koutsospyros, Agamemnon; Balas, Wendy; Nicolich, Steve; Sidhoum, Mohammed

    2009-01-01

    The aerobic biodegradability of the high explosive CL-20 by activated sludge and the white rot fungus Phanerochaete chrysosporium has been investigated. Although activated sludge is not effective in degrading CL-20 directly, it can mineralize the alkaline hydrolysis products. Phanerochaete chrysosporium degrades CL-20 in the presence of supplementary carbon and nitrogen sources. Biodegradation studies were conducted using various nutrient media under diverse conditions. Variables included the CL-20 concentration; levels of carbon (as glycerol) and ammonium sulfate and yeast extract as sources of nitrogen. Cultures that received CL-20 at the time of inoculation transformed CL-20 completely under all nutrient conditions studied. When CL-20 was added to pre-grown cultures, degradation was limited. The extent of mineralization was monitored by the 14CO2 time evolution; up to 51% mineralization was achieved when the fungus was incubated with [14C]-CL-20. The kinetics of CL-20 biodegradation by Phanerochaete chrysosporium follows the logistic kinetic growth model. PMID:19440524

  7. Decomposition and Performance of New High Nitrogen Propellants and Explosives.

    SciTech Connect

    Tappan, B. C.; Son, S. F.; Ali, A. N.; Chavez, D. E.; Hiskey, M. A.

    2005-01-01

    As of late, molecules with high nitrogen content have received increased attention, due in large part to their novel energetic materials properties. At the Los Alamos National Laboratory, we continue to pursue the development and characterization of new high-nitrogen materials for applications in a wide variety of fields. In this work three molecules, triaminoguanidinium azotetrazolate (TAGzT), 3,6-bis-nitroguanyl-1,2,4,5-tetrazine and its corresponding bis-triaminoguanidinium salt, are studied all of which are high-nitrogen compounds with little or no oxygen, however, retain energetic material properties as a result of their high heats of formation. Because of this, the decomposition of this class of compounds have limited or no secondary oxidation reactions of carbon and hydrogen. Other materials discussed for comparison include 3,3'-azobis(6-amino-1,2,4,5-tetrazine)-mixed N-oxides (DAATO{sub 3.5}) and 3,6-bis(1H-1,2,3,4-tetrazol-5-ylamino)-s-tetrazine (BTATz) and the nitramine octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). The fact that many of these molecules approach 80% nitrogen content makes them potentially useful as gas generants or energetic materials with low flame temperatures, while simultaneously increasing the impulse of gun or rocket propellants. The burning rate, flash pyrolysis (T-jump/FTIR spectroscopy), explosive sensitivity and performance properties were determined. Some examples of interesting behaviors include that TAGzT exhibits one of the fastest low pressure burning rates yet measured for an organic compound, and 3,6-bis-nitroguanyl-1,2,4,5-tetrazine has one of the lowest pressure exponents yet measured for a pure organic compound.

  8. Particle characteristics of trace high explosives: RDX and PETN.

    PubMed

    Verkouteren, Jennifer R

    2007-03-01

    The sizes of explosives particles in fingerprint residues produced from C-4 and Semtex-1A were investigated with respect to a fragmentation model. Particles produced by crushing crystals of RDX and PETN were sized by using scanning electron microscopy, combined with image analysis, and polarized light microscopy was used for imaging and identifying explosive particles in fingerprint residues. Crystals of RDX and PETN fragment in a manner that concentrates mass in the largest particles of the population, which is common for a fragmentation process. Based on the fingerprints studied, the particle size to target for improving mass detection in fingerprint residues by ion mobility spectrometry (IMS) is > or = 10 microm in diameter. Although particles smaller than 10 microm in diameter have a higher frequency, they constitute < 20% of the total mass. Efforts to improve collection efficiency of explosives particles for detection by IMS, or other techniques, must take into consideration that the mass may be concentrated in a relatively few particles that may not be homogeneously distributed over the fingerprint area. These results are based on plastic-bonded explosives such as C-4 that contain relatively large crystals of explosive, where fragmentation is the main process leading to the presence of particles in the fingerprint residues.

  9. Pressure Wave Measurements During Thermal Explosion of HMX-Based High Explosives

    SciTech Connect

    Forbes, J W; Garcia, F; Tarver, C M; Urtiew, P A; Greenwood, D W; Vandersall, K S

    2002-06-27

    Five different experiments on thermal heating of explosive materials have been performed. Three experiments thermally exploded PBX 9501 (HMX/Estane/BDNPA-F; 9512.512.5 wt %) donor charges while two others thermally exploded LX-04 (HMX/Viton A; 85/15 wt %). These donor charges were encased in 304 stainless steel. The transmitted two-dimensional pressure waves were measured by gauges in acceptor cylinders of Teflon, PBX 9501, or LX-04 that were in contact with the donors' steel case. A fifth experiment measured the pressure in an acceptor charge of PBX 9501 that had a 100 mm stand-off from the top of the steel case of the thermally cooked off PBX 9501 donor charge. Reactive flow hydrodynamic modeling using a rapid deflagration velocity of approximately 500 m/s was able to reproduce the pressure gauge records for both the in contact and stand off experiments that used PBX 9501 donors and acceptors.

  10. Insensitive explosive

    SciTech Connect

    Lee, Kien-yin; Storm, C.B.

    1991-12-31

    This invention relates to the field of chemistry and, more particularly, to explosives. This invention is the result of a contract with the Department of Energy (Contract No. W-7405-ENG-36). It is desirable to use explosives in weapons and other applications which are less sensitive than the common explosives RDX, TNT, and HMX, since there have been catastrophic explosions of munitions which use these compounds. In preliminary characterization and sensitivity testing, it has been found that 3-amino-5-nitro-1,2,4-triazole (ANTA) is a promising insensitive high explosive. This report details the safety, production, and physical properties of ANTA.

  11. The analysis of high explosives by liquid chromatography/electrospray ionization mass spectrometry: multiplexed detection of negative ion adducts.

    PubMed

    Mathis, John A; McCord, Bruce R

    2005-01-01

    The negative ion electrospray ionization mass spectrometric (ESI-MS) detection of adducts of high explosives with chloride, formate, acetate, and nitrate was used to demonstrate the gas-phase interaction of neutral explosives with these anions. The relative intensities of the adduct species were determined to compare the competitive formation of the selected high explosives and anions. The relative stability of the adduct species varies, yielding preferential formation of certain anionic adducts with different high explosives. To exploit this effect, an isocratic high-performance liquid chromatography (HPLC)/ESI-MS method was developed and used for the simultaneous analysis of high explosives using two different techniques for the addition of the anionic additives; pre- and post-column. The results show that the pre-column approach provides similar results with improved selectivity for specific explosives. By detecting characteristic adduct species for each explosive, this method provides a qualitative and quantitative approach for the analysis and identification of high explosives.

  12. High-Explosive Cratering a Frozen and Unfrozen Soils in Alaska

    DTIC Science & Technology

    1980-02-01

    CNN L 7E7 High-explosive cratering in frozen and unfrozen soils in Alaska T~I, LAOA c=29 Cover: Large cratering charge of pelletized TNT in thawed...silt underlain by permafrost. (Photograph by North Smith.) L C R RE R~mr-80-9 High-explosive cratering inirozen and’ S Unfrozen soils in Alaska * _North...COVERED HIGH-EXPLOSIVE CRATERING IN FROZEN ANFROZEN - SOILS IN ALASKA 6. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(a) 8. CONTRACT OR GRANT NUMBER(e) North

  13. Investigation of shear stress on a shock front in solid high explosives (HE)

    SciTech Connect

    Bat'kov, Y.V.; Fishman, N.D.; Novikov, S.A.

    1983-11-01

    This article gives results of an experimental investigation of the dependence of the critical shear stress at the shock front in cast TNT and in a cast TH 50/50 composite on the magnitude of the shock compression pressure in a range to 4.0 GPa (e.g. to the beginning of excitation of the explosive transformation). The principal stresses were measured by manganin sensors located in the high explosive under investigation in two mutually perpendicular directions in the tests. Stationary shocks were produced in the explosive specimens under investigation by using an explosive apparatus of the ''laminate'' type. It is determined that the magnitude of the shear stress grows linearly for the cast explosives investigated as the pressure grows, and exceeds considerably the static values of the shear strength.

  14. High Explosive Moulding Powders from RDX and Aqueous Polyurethane Dispersions,

    DTIC Science & Technology

    1987-05-01

    polybutadiene (17] type by reaction with low molecular weight diisocyanates in the absence of water. Explosive moulding powders incorporating...polyaddition reaction . The final polymers have predominantly hydrophobic long chain segments of the polyether or polyester type and also contain some...reacted with isocyanate groups in reaction sequences which ultimately yield either polyurethane or polyurethane-urea polymers. Three of the methods for

  15. Detonation Initiation of Heterogeneous Melt-Cast High Explosives

    NASA Astrophysics Data System (ADS)

    Chuzeville, Vincent; Baudin, Gerard; Lefrancois, Alexandre; Boulanger, Remi; Catoire, Laurent

    2015-06-01

    The melt-cast explosives' shock initiation mechanisms are less investigated than pressed and cast-cured ones. If the existence of hot-spots is widely recognized, their formation mechanism is not yet established. We study here two melt-cast explosives, NTO-TNT 60:40 and RDX-TNT 60:40 in order to establish a relation between the microstructure and the reaction rate using a two-phase model based on a ZND approach. Such a model requires the reaction rate, the equations of state of the unreacted phase and of the detonation products and an interaction model between the two phases to describe the reaction zone thermodynamics. The reaction rate law can be written in a factorized form including the number of initiation sites, the explosive's deflagration velocity around hot spots and a function depending on gas volume fraction produced by the deflagration front propagation. The deflagration velocity mainly depends on pressure and is determined from pop-plot tests using the hypothesis of the single curve build-up. This hypothesis has been verified for our two melt-cast explosives. The function depending on gas volume fraction is deduced from microstructural observations and from an analogy with the solid nucleation and growth theory. It has been established for deflagration fronts growing from grain's surface and a given initial grain size distribution. The model requires only a few parameters, calibrated thanks to an inversion method. A good agreement is obtained between experiments and numerical simulations.

  16. High explosive corner turning performance and the LANL mushroom test

    SciTech Connect

    Hill, L.G.; Seitz, W.L.; Forest, C.A.; Harry, H.H.

    1998-07-01

    The Mushroom test is designed to characterize the corner turning performance of a new generation of less sensitive booster explosives. The test is described in detail, and three corner turning figures-of-merit are examined using pure TATB (both Livermore{close_quote}s Ultrafine and a Los Alamos research blend) and PBX9504 as examples. {copyright} {ital 1998 American Institute of Physics.}

  17. High explosive corner turning performance and the LANL Mushroom test

    SciTech Connect

    Hill, L.G.; Seitz, W.L.; Forest, C.A.; Harry, H.H.

    1997-09-01

    The Mushroom test is designed to characterize the corner turning performance of a new generation of less insensitive booster explosives. The test is described in detail, and three corner turning figures-of-merit are examined using pure TATB (both Livermore`s Ultrafine and a Los Alamos research blend) and PBX9504 as examples.

  18. Accuracy and Calibration of High Explosive Thermodynamic Equations of State

    DTIC Science & Technology

    2010-08-01

    EIGENVALUE DETONATION Previous studies have shown that the traditional Chapman - Jouguet detonation theory does not explain the observed detonation...PAX- 30 and PAX-29 explosives produce eigenvalue, rather than traditional Chapman - Jouguet detonations, a modified analytic cylinder test model was...the expanding detonation products from the Chapman - Jouguet state. In addition, constant detonation products are assumed across spherical surfaces

  19. Safety Guidelines for Laser Illumination on Exposed High Explosives and Metals in Contact with High Explosives with Calculational Results

    SciTech Connect

    Benterou, J; Roeske, F; Wilkins, P; Carpenter, K H

    2002-04-17

    Experimental tests have been undertaken to determine safe levels of laser exposure on bare high explosive (HE) samples and on common metals used in intimate contact with HE. Laser light is often focused on bare HE and upon metals in contact with HE during alignment procedures and experimental metrology experiments. This paper looks at effects caused by focusing laser beams at high energy densities directly onto the surface of various bare HE samples. Laser energy densities (fluence) exceeding 19 kilowatts/cm{sup 2} using a 5-milliwatt, 670 nm, cw laser diode were generated by focusing the laser down to a spot size diameter of 4 microns. Upon careful inspection, no laser damage was observed in any of the HE samples illuminated at this fluence level. Direct laser exposure of metals directly contacting HE surfaces was also tested. Laser energy densities (fluence) varying from 188 Watts/cm{sup 2} to 12.7 KW/cm{sup 2} were generated using an 11-Watt, 532 nm frequency-doubled Nd:YAG cw laser with focal spot size diameters as small as 100 microns. These measurements look at the temperature rise of the surface of the metal in contact with HE when laser energy is incident on the opposite side of the metal. The temperature rise was experimentally measured as a function of incident laser power, spot size, metal composition and metal thickness. Numerical simulations were also performed to solve the two-dimensional heat flow problem for this experimental geometry. In order to simplify the numerical simulation to allow representation of a large number of physical cases, the equations used in the simulation are expressed in terms of dimensionless variables. The normalized numerical solutions are then compared to the various experimental configurations utilized. Calculations and experiment agree well over the range measured. Safety guidelines for alignment laser illumination upon bare HE are outlined.

  20. iVCJ: A tool for Interactive Visualization of high explosives CJ states

    SciTech Connect

    Wooten, Hasani Omar; Aslam, Tariq Dennis; Whitley, Von Howard

    2016-12-12

    A graphical user interface (GUI) tool has been developed that facilitates the visualization and analysis of the Chapman-Jouguet state for high explosives gaseous products using the Jones- Wilkins-Lee equation of state.

  1. Biodegradation of high explosives on granular activated carbon [GAC]: Enhanced desorption of high explosives from GAC -- Batch studies

    SciTech Connect

    Morley, M.C.; Speitel, G.E. Jr.

    1999-03-01

    Adsorption to GAC is an effective method for removing high explosives (HE) compounds from water, but no permanent treatment is achieved. Bioregeneration, which treats adsorbed contaminants by desorption and biodegradation, is being developed as a method for reducing GAC usage rates and permanently degrading RDX and HMX. Because desorption is often the limiting mass transfer mechanism in bioregeneration systems, several methods for increasing the rate and extent of desorption of RDX and HMX are being studied. These include use of cosolvents (methanol and ethanol), surfactants (both anionic and nonionic), and {beta}- and {gamma}-cyclodextrins. Batch experiments to characterize the desorption of these HEs from GAC have been completed using Northwestern LB-830, the GAC being used at Pantex. Over a total of 11 days of desorption, about 3% of the adsorbed RDX was desorbed from the GAC using buffered water as the desorption fluid. In comparison, about 96% of the RDX was extracted from the GAC by acetonitrile over the same desorption period. Ethanol and methanol were both effective in desorbing RDX and HMX; higher alcohol concentrations were able to desorb more HE from the GAC. Surfactants varied widely in their abilities to enhance desorption of HEs. The most effective surfactant that was studied was sodium dodecyl sulfate (SDS), which desorbed 56.4% of the adsorbed RDX at a concentration of 500 mg SDS/L. The cyclodextrins that were used were marginally more effective than water. Continuous-flow column tests are underway for further testing the most promising of these methods. These results will be compared to column experiments that have been completed under baseline conditions (using buffered water as the desorption fluid). Results of this research will support modeling and design of further desorption and bioregeneration experiments.

  2. Explosion of heterogeneous water droplet in a high-temperature gaseous region

    NASA Astrophysics Data System (ADS)

    Piskunov, M. V.; Shcherbinina, A. A.

    2015-11-01

    Using high-speed video recording tools (up to 105 frames per second) and «TEMA Automotive» and «Phantom Camera Control» software packages the experimental features of explosive disintegration, boiling and evaporation of water droplets with comparably sized solid inclusions heated in high-temperature (more than 650 K) gaseous region were determined. The necessary and sufficient conditions of explosive vapor formation achievement with the next heterogeneous water droplet disintegration were found.

  3. Characterization of high-explosive initiation and safety at Los Alamos

    SciTech Connect

    McAfee, J.M.

    1994-10-01

    The Chapman-Jouget and ZND models of steady detonation have proved most useful for engineering estimation of the propagation of near-planar, steady detonation in short-reaction-zone explosives. However, even in well characterized systems, the purposeful initiation of detonation is not described by these models. The highly divergent and microscopic nature of point initiation require discerning experiments, modeling, and theoretical analysis. Recently, safety considerations in complex or damaged systems, possibly containing long-reaction-zone (insensitive) high explosives, have dominated the author`s thinking. These situations are rarely planar or steady, the physical state of the explosive may not be easily characterized, and there is a wide range of potential stimuli. The high-explosive reaction may range from none, to deflagration, to partial detonation, or to full detonation. Techniques and data applicable to estimating the level of response are needed.

  4. An explicit model of expanding cylindrical shells subjected to high explosive detonations

    SciTech Connect

    Martineau, R.L.; Prime, M.B.; Anderson, C.A.; Smith, F.W.

    1999-04-01

    A viscoplastic constitutive model was formulated to model the high strain-rate expansion of thin cylindrical shells subjected to internal explosive detonations. This model provides insight into the development of plastic instabilities, which occur on the surface of the shells prior to failure. The effects of shock heating and damage in the form of microvoid nucleation, growth, and coalescence were incorporated using the Johnson-Cook strength model with the Mie-Grueneisen equation of state and a modified Gurson yield surface. This model was implemented into ABAQUS/Explicit as a user material subroutine. A cylindrical copper shell was modeled using both axisymmetric and plane strain elements. The high explosive material inside of the cylinder was simulated using the high explosive burn model in ABAQUS/Explicit. Two experiments were conducted involving explosive-filled, copper cylinders and good agreement was obtained between the numerical results and experimental data.

  5. Motivation for a High Explosive Testing Program in South Africa

    DTIC Science & Technology

    2015-12-04

    understanding earthquake source mechanisms. Of special interest to the research community associated with Comprehensive Test Ban Treaty (CTBT) activities...burst or natural earthquake . This paper provides background information on previous research in and around the deep mines of South Africa and lays...spectra and source parameters agree well with standard earthquake source  models.” The “explosions typically have higher corner frequencies than

  6. IMAGING HIGH SPEED PARTICLES IN EXPLOSIVE DRIVEN BLAST WAVES

    SciTech Connect

    Jenkins, C. M.; Horie, Y.; Ripley, R. C.; Wu, C.-Y.

    2009-12-28

    This research describes a new application of a commercially available particle image velocimetry (PIV) instrument adapted for imaging particles in a blast wave. Powder was dispersed through the PIV light sheet using a right circular cylindrical charge containing aluminum powder filled in the annular space between the explosive core and exterior paper tube wall of the charge. Images acquired from each shot showed particle agglomeration and unique structures with the smaller particle diameters having developed structured appearances.

  7. Advanced Radiometry for High Discrimination Explosive Fireball Discrimination

    DTIC Science & Technology

    2009-03-01

    focal plane array at 30 Hz observed in the near infrared spectrum and a Canon XL-1 3 chip video camera provided audio-visual documentation of the test...John Wiley & Sons, Inc, 2007. 6. Smith, B. (1996). How an FTIR works. Fundamentals of fourier transform infrared spectroscopy (First ed., pp. 15-22...explosive (HE) fireball emission phenomenological model in the mid-wave infrared (MWIR) spectrum to perform discrimination. This consists of five

  8. Hot-spot contributions in shocked high explosives from mesoscale ignition models

    NASA Astrophysics Data System (ADS)

    Levesque, G.; Vitello, P.; Howard, W. M.

    2013-06-01

    High explosive performance and sensitivity is strongly related to the mesoscale defect densities. Bracketing the population of mesoscale hot spots that are active in the shocked ignition of explosives is important for the development of predictive reactive flow models. By coupling a multiphysics-capable hydrodynamics code (ale3d) with a chemical kinetics solver (cheetah), we can parametrically analyze different pore sizes undergoing collapse in high pressure shock conditions with evolving physical parameter fields. Implementing first-principles based decomposition kinetics, burning hot spots are monitored, and the regimes of pore sizes that contribute significantly to burnt mass faction and those that survive thermal conduction on the time scales of ignition are elucidated. Comparisons are drawn between the thermal explosion theory and the multiphysics models for the determination of nominal pore sizes that burn significantly during ignition for the explosive 1,3,5-triamino-2,4,6-trinitrobenzene.

  9. Role of explosive instabilities in high-β disruptions in tokamaks

    NASA Astrophysics Data System (ADS)

    Aydemir, A. Y.; Lee, H. H.; Lee, S. G.; Seol, J.; Park, B. H.; In, Y. K.

    2016-05-01

    Intrinsically explosive growth of a ballooning finger is demonstrated in nonlinear magnetohydrodynamic calculations of high-β disruptions in tokamaks. The explosive finger is formed by an ideally unstable n  =  1 mode, dominated by an m/n  =  2/1 component. The quadrupole geometry of the 2/1 perturbed pressure field provides a generic mechanism for the formation of the initial ballooning finger and its subsequent transition from exponential to explosive growth, without relying on secondary processes. The explosive ejection of the hot plasma from the core and stochastization of the magnetic field occur on Alfvénic time scales, accounting for the extremely fast growth of the precursor oscillations and the rapidity of the thermal quench in some high-β disruptions.

  10. Thermal treatment of high explosives at Mason & Hanger/Pantex Plant

    SciTech Connect

    Patterson, W.E.; Phelan, P.F.

    1993-12-31

    The Pantex plant presently processes about 45,000 kg (100,000 lb) of high explosives annually by outdoor burning. About half of the explosives are weapon components weighing over 5 kg (10 lb) which come directly out of nuclear weapons being removed from the stockpile. The other half is generated from various support processes, special tests, etc. Burning serves the three-fold purpose of demilitarizing, removing all classified characteristics, and eliminating the severe hazard posed by the explosives themselves. Transporting such large quantities of classified high explosives for such processing at another site would be prohibitive. Computerized atmospheric modelling of the burning process was conducted during the past year. The results were somewhat surprising in that oxides of nitrogen and carbon monoxide, two ``criteria pollutants,`` were not of great concern even though it is known that high explosives contain significant amounts of nitrogen and they generate measureable amounts of carbon monoxide when they are burned. Rather, it was determined that hydrogen fluoride gas is of much greater concern, and stringent controls on the burning operation have been implemented to address this concern. Although the amount of fluorine-containing explosive must be restricted, other kinds of air emissions are not a great concern. This favorable situation is largely due to the flat, featureless, sparsely inhabited terrain, the distance to the nearest plant boundary, the wind, the lack of stagnant atmospheric conditions, and the tremendous rate of heat release.

  11. A simple approach for determining detonation velocity of high explosive at any loading density.

    PubMed

    Keshavarz, Mohammad Hossein

    2005-05-20

    A simple empirical relationship is introduced between detonation velocity at any loading density and chemical composition of high explosive as well as its gas phase heat of formation, which is calculated by group additivity rules. The present work may be applied to any explosive that contains the elements of carbon, hydrogen, nitrogen and oxygen with no difficulties. The new correlation can easily be applied for determining detonation velocity of explosives with loading densities less than 1g/cm3 as well as greater than 1g/cm3. Calculated detonation velocities by this procedure for both pure and explosive formulations show good agreement with respect to measured detonation velocity over a wide range of loading density.

  12. Strategies for the disposition of high explosives resulting from dismantlement of nuclear weapons

    SciTech Connect

    Pruneda, C.; Humphrey, J.

    1993-03-01

    Many thousands of pounds of high quality main-charge explosives will result as surplus from the dismantlement of returns from the US nuclear weapons stockpile. The method most often employed for dealing with this surplus explosive is destruction by open burning. However, open burning as a means of treating excess explosives is losing favor because of environmental concerns associated with such an uncontrolled thermal destruction process. Thus, alternative processes for treatment of excess explosives from weapon dismantlement is discussed. These alternatives include: reformulation, crystalline component recovery, chemical conversion of the crystalline component to higher value products which may have civilian or military applications and, when necessary, treatment as waste in an environmentally benign fashion.

  13. Explosives in the Cage: Metal-Organic Frameworks for High-Energy Materials Sensing and Desensitization.

    PubMed

    Wang, Shan; Wang, Qianyou; Feng, Xiao; Wang, Bo; Yang, Li

    2017-07-21

    An overview of the current status of coordination polymers and metal-organic frameworks (MOFs) pertaining to the field of energetic materials is provided. The explosive applications of MOFs are discussed from two aspects: one for detection of explosives, and the other for explosive desensitization. By virtue of their adjustable pore/cage sizes, high surface area, tunable functional sites, and rich host-guest chemistry, MOFs have emerged as promising candidates for both explosive sensing and desensitization. The challenges and perspectives in these two areas are thoroughly discussed, and the processing methods for practical applications are also discussed briefly. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Analysis of xRAGE and flag high explosive burn models with PBX 9404 cylinder tests

    SciTech Connect

    Harrier, Danielle; Andersen, Kyle Richard

    2016-08-05

    High explosives are energetic materials that release their chemical energy in a short interval of time. They are able to generate extreme heat and pressure by a shock driven chemical decomposition reaction, which makes them valuable tools that must be understood. This study investigated the accuracy and performance of two Los Alamos National Laboratory hydrodynamic codes, which are used to determine the behavior of explosives within a variety of systems: xRAGE which utilizes an Eulerian mesh, and FLAG with utilizes a Lagrangian mesh. Various programmed and reactive burn models within both codes were tested using a copper cylinder expansion test. The test was based on a recent experimental setup which contained the plastic bonded explosive PBX 9404. Detonation velocity versus time curves for this explosive were obtained using Photon Doppler Velocimetry (PDV). The modeled results from each of the burn models tested were then compared to one another and to the experimental results. This study validate

  15. Computer code to predict the heat of explosion of high energy materials.

    PubMed

    Muthurajan, H; Sivabalan, R; Pon Saravanan, N; Talawar, M B

    2009-01-30

    The computational approach to the thermochemical changes involved in the process of explosion of a high energy materials (HEMs) vis-à-vis its molecular structure aids a HEMs chemist/engineers to predict the important thermodynamic parameters such as heat of explosion of the HEMs. Such a computer-aided design will be useful in predicting the performance of a given HEM as well as in conceiving futuristic high energy molecules that have significant potential in the field of explosives and propellants. The software code viz., LOTUSES developed by authors predicts various characteristics of HEMs such as explosion products including balanced explosion reactions, density of HEMs, velocity of detonation, CJ pressure, etc. The new computational approach described in this paper allows the prediction of heat of explosion (DeltaH(e)) without any experimental data for different HEMs, which are comparable with experimental results reported in literature. The new algorithm which does not require any complex input parameter is incorporated in LOTUSES (version 1.5) and the results are presented in this paper. The linear regression analysis of all data point yields the correlation coefficient R(2)=0.9721 with a linear equation y=0.9262x+101.45. The correlation coefficient value 0.9721 reveals that the computed values are in good agreement with experimental values and useful for rapid hazard assessment of energetic materials.

  16. High methane natural gas/air explosion characteristics in confined vessel.

    PubMed

    Tang, Chenglong; Zhang, Shuang; Si, Zhanbo; Huang, Zuohua; Zhang, Kongming; Jin, Zebing

    2014-08-15

    The explosion characteristics of high methane fraction natural gas were investigated in a constant volume combustion vessel at different initial conditions. Results show that with the increase of initial pressure, the peak explosion pressure, the maximum rate of pressure rise increase due to a higher amount (mass) of flammable mixture, which delivers an increased amount of heat. The increased total flame duration and flame development time result as a consequence of the higher amount of flammable mixture. With the increase of the initial temperature, the peak explosion pressures decrease, but the pressure increase during combustion is accelerated, which indicates a faster flame speed and heat release rate. The maximum value of the explosion pressure, the maximum rate of pressure rise, the minimum total combustion duration and the minimum flame development time is observed when the equivalence ratio of the mixture is 1.1. Additionally, for higher methane fraction natural gas, the explosion pressure and the maximum rate of pressure rise are slightly decreased, while the combustion duration is postponed. The combustion phasing is empirically correlated with the experimental parameters with good fitting performance. Furthermore, the addition of dilute gas significantly reduces the explosion pressure, the maximum rate of pressure rise and postpones the flame development and this flame retarding effect of carbon dioxide is stronger than that of nitrogen. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. A novel method for the measurement of the von Neumann spike in detonating high explosives

    NASA Astrophysics Data System (ADS)

    Sollier, A.; Bouyer, V.; Hébert, P.; Doucet, M.

    2016-06-01

    We present detonation wave profiles measured in T2 (97 wt. % TATB) and TX1 (52 wt. % TATB and 45 wt. % HMX) high explosives. The experiments consisted in initiating a detonation wave in a 15 mm diameter cylinder of explosive using an explosive wire detonator and an explosive booster. Free surface velocity wave profiles were measured at the explosive/air interface using a Photon Doppler Velocimetry system. We demonstrate that a comparison of these free surface wave profiles with those measured at explosive/window interfaces in similar conditions allows to bracket the von Neumann spike in a narrow range. For T2, our measurements show that the spike pressure lies between 35.9 and 40.1 GPa, whereas for TX1, it lies between 42.3 and 47.0 GPa. The numerical simulations performed in support to these measurements show that they can be used to calibrate reactive burn models and also to check the accuracy of the detonation products equation of state at low pressure.

  18. Hydrogen Cylinder Storage Array Explosion Evaluations at the High Flux Isotope Reactor

    SciTech Connect

    Cook, David Howard; Griffin, Frederick P; Hyman III, Clifton R

    2010-01-01

    The safety analysis for a recently-installed cold neutron source at the High Flux Isotope Reactor (HFIR) involved evaluation of potential explosion consequences from accidental hydrogen jet releases that could occur from an array of hydrogen cylinders. The scope of the safety analysis involved determination of the release rate of hydrogen, the total quantity of hydrogen assumed to be involved in the explosion, the location of an ignition point or center of the explosion from receptors of interest, and the peak overpressure at the receptors. To evaluate the total quantity of hydrogen involved in the explosion, a 2D model was constructed of the jet concentration and a radial-axial integral over the jet cloud from the centerline to the flammability limit of 4% was used to determine the hydrogen mass to be used as a source term. The location of the point source was chosen as the peak of the jet centerline concentration profile. Consequences were assessed using a combination of three methods for estimating local overpressure as a function of explosion source strength and distance: the Baker-Strehlow method, the TNT-equivalence method, and the TNO method. Results from the explosions were assessed using damage estimates in screening tables for buildings and industrial equipment.

  19. A novel method for the measurement of the von Neumann spike in detonating high explosives

    SciTech Connect

    Sollier, A.; Bouyer, V.; Hébert, P.; Doucet, M.

    2016-06-28

    We present detonation wave profiles measured in T2 (97 wt. % TATB) and TX1 (52 wt. % TATB and 45 wt. % HMX) high explosives. The experiments consisted in initiating a detonation wave in a 15 mm diameter cylinder of explosive using an explosive wire detonator and an explosive booster. Free surface velocity wave profiles were measured at the explosive/air interface using a Photon Doppler Velocimetry system. We demonstrate that a comparison of these free surface wave profiles with those measured at explosive/window interfaces in similar conditions allows to bracket the von Neumann spike in a narrow range. For T2, our measurements show that the spike pressure lies between 35.9 and 40.1 GPa, whereas for TX1, it lies between 42.3 and 47.0 GPa. The numerical simulations performed in support to these measurements show that they can be used to calibrate reactive burn models and also to check the accuracy of the detonation products equation of state at low pressure.

  20. Determination of detonation parameters for liquid high explosives

    NASA Astrophysics Data System (ADS)

    Mochalova, Valentina; Utkin, Alexander

    2012-03-01

    The experimental investigation of detonation parameters and reaction zone structure in liquid HE (bis-(2-fluoro-2,2-dinitroethyl)formal (FEFO), tetranitromethane (TNM), nitromethane (NM)) was conducted by means of laser interferometer VISAR. Detonation front in TNM and NM was stable while the instability of detonation in FEFO was observed. The parameters of Von Neumann spike were determined for these HE. The different methods for C-J point determination were used for each HE. For FEFO reaction time t was found from experiments with different charge diameters (τ is approximately equal to 300 ns); for TNM - at fixed diameter and different lengths of charges (τ ≈ 200 ns); for NM - at fixed diameter and length of charges, but detonation initiation was carried out by different explosive charges (τ ≈ 50 ns). It was found that in TNM the detonation velocity depends on charge diameter. Maximum value of reaction rate in investigated liquid HE was observed after shock jump.

  1. Determination of detonation parameters for liquid High Explosives

    NASA Astrophysics Data System (ADS)

    Mochalova, Valentina; Utkin, Alexander

    2011-06-01

    The experimental investigation of detonation parameters and reaction zone structure in liquid HE (bis-(2-fluoro-2,2-dinitroethyl)formal (FEFO), tetranitromethane (TNM), nitromethane (NM)) was conducted. Detonation front in TNM and NM was stable while the instability of detonation in FEFO was observed. Von Neumann spike was recorded for these HE and its parameters were determined. The different methods for C-J point determination were used for each HE. For FEFO reaction time τ was found from experiments with different charge diameters (τ is approximately equal to 300 ns); for TNM - at fixed diameter and different lengths of charges (τ ~ 200 ns); for NM - at fixed diameter and length of charges, but detonation initiation was carried out by different explosive charges (τ ~ 50 ns). It was found that in TNM the detonation velocity depends on charge diameter. Maximum value of reaction rate in investigated liquid HE was observed after shock jump and induction time was not recorded.

  2. Initiation of detonation by a high-voltage discharge in powdered explosives with nanosize inert admixtures

    NASA Astrophysics Data System (ADS)

    Rashkovskii, S. A.; Savenkov, G. G.

    2013-04-01

    It is shown that admixtures of a copper nanopowder in a high-disperse low-sensitivity explosive of the FOX-7 type sharply increase the sensitivity of the mixture to the action of a high-voltage electric discharge and facilitate detonation. The percolation model of propagation of the electric breakdown over a powdered mixture with nanosize admixtures and the model of initiation of detonation by a high-voltage discharge in the mixture of a brisant explosive with an inert admixture are developed. These models are in qualitative and quantitative agreement with experimental data.

  3. Magnetic gauge measurements on the two-stage gun : homogeneous and heterogeneous initiation of high explosives /

    SciTech Connect

    Gustavsen, R. L.; Alcon, R. R.; Davis, L. L.; Sheffield, S. A.

    2001-01-01

    One of the reasons for building our gas-driven two-stage gun at Los Alamos was to be able to do shock initiation experiments on high explosives that were too insensitive to initiate with the single-stage gun. In past ARA meetings we have discussed the operation of the gun and the magnetic gauge measurement method. During the past couple of years we have done a number of magnetic gauge experiments on both liquid and solid high explosives. Shock initiation of high explosives depends on the nature of the material - whether it is homogeneous (liquid) or heterogeneous (pressed solid). In the solid explosives, mostly heterogeneous behavior has been measured. In the liquid explosive isopropyl nitrate, classic homogeneous initiation has been measured including the formation of a superdetonation in the shocked liquid. Experiments in both materials are discussed including the particle (mass) velocity profiles at a number of Lagrangian positions in the flow, progress of the shock front as measured by shock tracker gauges, and the position when the reactive wave reaches a detonation condition. The two-stage gun, in conjunction with the multiple magnetic gauging method, has proven very useful for generating new information in initiation experiments. Information from these experiments is of great value to modelers trying to determine the proper reaction rate models to use in simulations of the shock initiation process.

  4. High-performance, extrusion-cast explosives with low sensitivity: Interim report No. 2

    SciTech Connect

    Scribner, K.J.; von Holtz, E.; Simpson, R.L.

    1989-01-10

    Lawrence Livermore National Laboratory (LLNL) has developed a class of explosives having both high performance for modern precision munitions and greater safety for reduced vulnerability of launch platforms (ships, planes, ammunition storage sites) to enemy fire or accidents. Known as extrusion-cast explosives (ECXs), they have demonstrated performance levels equivalent to the most powerful now available, but test results indicate they are far less sensitive than the conventional high-energy explosives. Specifically, in a sympathetic-detonation test, ECX that was immediately adjacent to a deliberately-detonated donor charge did not detonate in two of three tests, whereas Comp B did detonate sympathetically in this test. Also, this ECX provided performance equivalent to that of the high-performance explosive LX-14, when tested in the TOW (tube-launched, optically-sighted, wire-guided) missile. This report describes the performance, vulnerability, and processing (at this stage of development) of this class of explosives. 9 refs., 18 figs., 11 tabs.

  5. Identification of high explosive RDX using terahertz imaging and spectral fingerprints

    NASA Astrophysics Data System (ADS)

    Liu, Jia; Fan, Wen-Hui; Chen, Xu; Xie, Jun

    2016-01-01

    We experimentally investigated the spectral fingerprints of high explosive cyclo-1,3,5- trimethylene-2,4,6-trinitramine (RDX) in terahertz frequency region. A home-made terahertz time-domain spectroscopy ranging from 0.2 THz∼ 3.4 THz was deployed. Furthermore, two sample pellets (RDX pellet and polyethylene pellet), which were concealed in an opaque envelop, could be identified by using terahertz pulse imaging system. For the purpose of distinguishing the RDX between two pellets, we further calculated the THz frequency -domain map using its spectral fingerprints. It is demonstrated that the high explosive RDX could similarly be identified using terahertz frequency-domain imaging.

  6. Analysis of Xrage and Flag High Explosive Burn Models with PBX 9404 Cylinder Tests

    NASA Astrophysics Data System (ADS)

    Harrier, Danielle; Fessenden, Julianna; Ramsey, Scott

    2016-11-01

    High explosives are energetic materials that release their chemical energy in a short interval of time. They are able to generate extreme heat and pressure by a shock driven chemical decomposition reaction, which makes them valuable tools that must be understood. This study investigated the accuracy and performance of two Los Alamos National Laboratory hydrodynamic codes, which are used to determine the behavior of explosives within a variety of systems: xRAGE which utilizes an Eulerian mesh, and FLAG with utilizes a Lagrangian mesh. Various programmed and reactive burn models within both codes were tested, using a copper cylinder expansion test. The test was based off of a recent experimental setup which contained the plastic bonded explosive PBX 9404. Detonation velocity versus time curves for this explosive were obtained from the experimental velocity data collected using Photon Doppler Velocimetry (PDV). The modeled results from each of the burn models tested were then compared to one another and to the experimental results using the Jones-Wilkins-Lee (JWL) equation of state parameters that were determined and adjusted from the experimental tests. This study is important to validate the accuracy of our high explosive burn models and the calibrated EOS parameters, which are important for many research topics in physical sciences.

  7. Explosive generation of high magnetic fields in large volumes and solid state applications

    SciTech Connect

    Fowler, C.M.; Caird, R.S.; Erickson, D.J.; Freeman, B.L.; Garn, W.B.

    1980-01-01

    Various methods of producing ultra-high magnetic fields by explosive flux compression are described. A survey is made of the kinds of high magnetic field solid state data obtained in such fields by various groups. Preliminary results are given for the magnetic phase boundary that separates the spin-flop and paramagnetic regions of MnF/sub 2/.

  8. Lawrence Livermore Laboratory's beryllium control program for high-explosive test firing bunkers and tables

    SciTech Connect

    Johnson, J.S.

    1980-11-25

    This report on the control program to minimize beryllium levels in Laboratory workplaces includes an outline of beryllium surface, soil, and air levels and an 11-y summary of sampling results from two high-use, high-explosive test firing bunkers. These sampling data and other studies demonstrate that the beryllium control program is functioning effectively.

  9. Prediction of initiation of low and high explosive fillers due to fragment or projectile impact

    NASA Technical Reports Server (NTRS)

    Zabel, P. H.; Parr, V. B.

    1980-01-01

    A methodology is presented which provides predictions for the probability of initiation of explosion in high explosive filled warheads and in propellant filled rocket motor cases given the impact of compact fragments or of small projectiles. Equations of velocities at which 50 percent of the explosive filled cases will initiate either high or low order are developed for compact fragments, and for projectiles. These data are used to establish the standard deviation of the data from the 50 percent initiation line. Standard deviation is used to provide predictions of the probability of initiation given the impact velocity and other pertinent parameters using equations and logic which are established in a computer model. This computer model uses fragment material properties and encounter parameters to predict fragment impact initiation, and projectile and casing material properties and encounter parameters to predict projectile impact initiation.

  10. a Verification and Validation Effort for High Explosives at LOS Alamos National Lab

    NASA Astrophysics Data System (ADS)

    Scovel, C. A.; Menikoff, R.

    2009-12-01

    We have started a project to verify and validate ASC codes used to simulate detonation waves in high explosives. Since there are no non-trivial analytic solutions, we are going to compare simulated results with experimental data that cover a wide range of explosive phenomena. The intent is to compare both different codes and different high explosives (HE) models. The first step is to test the products equation of state used for the HE models. For this purpose, the cylinder test, flyer plate and plate-push experiments are being used. These experiments sample different regimes in thermodynamic phase space: the CJ isentrope for the cylinder tests, the isentrope behind an overdriven detonation wave for the flyer plate experiment, and expansion following a reflected CJ detonation for the pate-push experiment, which is sensitive to the Gruneisen coefficient.

  11. Prediction of initiation of low and high explosive fillers due to fragment or projectile impact

    NASA Technical Reports Server (NTRS)

    Zabel, P. H.; Parr, V. B.

    1980-01-01

    A methodology is presented which provides predictions for the probability of initiation of explosion in high explosive filled warheads and in propellant filled rocket motor cases given the impact of compact fragments or of small projectiles. Equations of velocities at which 50 percent of the explosive filled cases will initiate either high or low order are developed for compact fragments, and for projectiles. These data are used to establish the standard deviation of the data from the 50 percent initiation line. Standard deviation is used to provide predictions of the probability of initiation given the impact velocity and other pertinent parameters using equations and logic which are established in a computer model. This computer model uses fragment material properties and encounter parameters to predict fragment impact initiation, and projectile and casing material properties and encounter parameters to predict projectile impact initiation.

  12. A verification and validation effort for high explosives at Los Alamos National Lab (u)

    SciTech Connect

    Scovel, Christina A; Menikoff, Ralph S

    2009-01-01

    We have started a project to verify and validate ASC codes used to simulate detonation waves in high explosives. Since there are no non-trivial analytic solutions, we are going to compare simulated results with experimental data that cover a wide range of explosive phenomena. The intent is to compare both different codes and different high explosives (HE) models. The first step is to test the products equation of state used for the HE models, For this purpose, the cylinder test, flyer plate and plate-push experiments are being used. These experiments sample different regimes in thermodynamic phase space: the CJ isentrope for the cylinder tests, the isentrope behind an overdriven detonation wave for the flyer plate experiment, and expansion following a reflected CJ detonation for the plate-push experiment, which is sensitive to the Gruneisen coefficient. The results of our findings for PBX 9501 are presented here.

  13. Extrusion cast explosive

    DOEpatents

    Scribner, Kenneth J.

    1985-01-01

    Improved, multiphase, high performance, high energy, extrusion cast explosive compositions, comprising, a crystalline explosive material; an energetic liquid plasticizer; a urethane prepolymer, comprising a blend of polyvinyl formal, and polycaprolactone; a polyfunctional isocyanate; and a catalyst are disclosed. These new explosive compositions exhibit higher explosive content, a smooth detonation front, excellent stability over long periods of storage, and lower sensitivity to mechanical stimulants.

  14. Simulation Study of Near-Surface Coupling of Nuclear Devices vs. Equivalent High-Explosive Charges

    SciTech Connect

    Fournier, Kevin B; Walton, Otis R; Benjamin, Russ; Dunlop, William H

    2014-09-29

    A computational study was performed to examine the differences in near-surface ground-waves and air-blast waves generated by high-explosive energy sources and those generated by much higher energy - density low - yield nuclear sources. The study examined the effect of explosive-source emplacement (i.e., height-of-burst, HOB, or depth-of-burial, DOB) over a range from depths of -35m to heights of 20m, for explosions with an explosive yield of 1-kt . The chemical explosive was modeled by a JWL equation-of-state model for a ~14m diameter sphere of ANFO (~1,200,000kg – 1 k t equivalent yield ), and the high-energy-density source was modeled as a one tonne (1000 kg) plasma of ‘Iron-gas’ (utilizing LLNL’s tabular equation-of-state database, LEOS) in a 2m diameter sphere, with a total internal-energy content equivalent to 1 k t . A consistent equivalent-yield coupling-factor approach was developed to compare the behavior of the two sources. The results indicate that the equivalent-yield coupling-factor for air-blasts from 1 k t ANFO explosions varies monotonically and continuously from a nearly perfec t reflected wave off of the ground surface for a HOB ≈ 20m, to a coupling factor of nearly zero at DOB ≈ -25m. The nuclear air - blast coupling curve, on the other hand, remained nearly equal to a perfectly reflected wave all the way down to HOB’s very near zero, and then quickly dropped to a value near zero for explosions with a DOB ≈ -10m. The near - surface ground - wave traveling horizontally out from the explosive source region to distances of 100’s of meters exhibited equivalent - yield coupling - factors t hat varied nearly linearly with HOB/DOB for the simulated ANFO explosive source, going from a value near zero at HOB ≈ 5m to nearly one at DOB ≈ -25m. The nuclear-source generated near-surface ground wave coupling-factor remained near zero for almost all HOB’s greater than zero, and then appeared to vary nearly - linearly with depth

  15. High explosive spot test analyses of samples from Operable Unit (OU) 1111

    SciTech Connect

    McRae, D.; Haywood, W.; Powell, J.; Harris, B.

    1995-01-01

    A preliminary evaluation has been completed of environmental contaminants at selected sites within the Group DX-10 (formally Group M-7) area. Soil samples taken from specific locations at this detonator facility were analyzed for harmful metals and screened for explosives. A sanitary outflow, a burn pit, a pentaerythritol tetranitrate (PETN) production outflow field, an active firing chamber, an inactive firing chamber, and a leach field were sampled. Energy dispersive x-ray fluorescence (EDXRF) was used to obtain semi-quantitative concentrations of metals in the soil. Two field spot-test kits for explosives were used to assess the presence of energetic materials in the soil and in items found at the areas tested. PETN is the major explosive in detonators manufactured and destroyed at Los Alamos. No measurable amounts of PETN or other explosives were detected in the soil, but items taken from the burn area and a high-energy explosive (HE)/chemical sump were contaminated. The concentrations of lead, mercury, and uranium are given.

  16. Chemical warfare agent and high explosive identification by spectroscopy of neutron-induced gamma rays

    SciTech Connect

    Caffrey, A.J.; Cole, J.D.; Gehrke, R.J.; Greenwood, R.C. )

    1992-10-01

    This paper reports on a non-destructive assay method to identify chemical warfare (CW) agents and high explosive (HE) munitions which was tested with actual chemical agents and explosives at the Tooele Army Depot, Tooele, Utah, from 22 April 1991 through 3 May 1991. The assay method exploits the gamma radiation produced by neutron interactions inside a container or munition to identify the elemental composition of its contents. The characteristic gamma-ray signatures of the chemical elements chlorine, phosphorus, and sulfur were observed form the CW agent containers and munitions, in sufficient detail to enable us to reliably discern agents GB (sarin), HD (mustard gas), and VX from one another, and from HE-filled munitions. By detecting of the presence of nitrogen, the key indictor of explosive compounds, and the absence of elements Cl, P, and S, HE shells were also clearly identified.

  17. High-speed photography of the first hydrogen-bomb explosion

    NASA Astrophysics Data System (ADS)

    Brixner, Berlyn

    1993-01-01

    Obtaining detailed photographs of the early stages of the first hydrogen bomb explosion in 1952 posed a number of problems. First, it was necessary to invent a continuous-access camera which could solve the problem that existing million-picture-per-second cameras were blind most of the time. The solution here was to alter an existing camera design so that two modified cameras could be mounted around a single high-speed rotating mirror. A second problem, acquiring the necessary lenses of precisely specified focal lengths, was solved by obtaining a large number of production lenses from war surplus salvage. A third hurdle to be overcome was to test the new camera at an A-bomb explosion. Finally, it was necessary to solve the almost impossible difficulty of building a safe camera shelter close to a megaton explosion. This paper describes the way these problems were solved. Unfortunately the successful pictures that were taken are still classified.

  18. An Improved Reaction Rate Equation for Simulating the Ignition and Growth of Reaction in High Explosives

    SciTech Connect

    Murphy, M J

    2010-03-08

    We describe an improved reaction rate equation for simulating ignition and growth of reaction in high explosives. It has been implemented into CALE and ALE3D as an alternate to the baseline the Lee-Tarver reactive flow model. The reactive flow model treats the explosive in two phases (unreacted/reactants and reacted/products) with a reaction rate equation to determine the fraction reacted, F. The improved rate equation has fewer parameters, is continuous with continuous derivative, results in a unique set of reaction rate parameters for each explosive while providing the same functionality as the baseline rate equation. The improved rate equation uses a cosine function in the ignition term and a sine function in the growth and completion terms. The improved rate equation is simpler with fewer parameters.

  19. High-speed photography of the first hydrogen-bomb explosion

    SciTech Connect

    Brixner, B.

    1992-09-01

    Obtaining detailed photographs of the early stages of the first hydrogen bomb explosion in 1952 posed a number of problems. First, it was necessary to invent a continuous-access camera which could solve the problem that existing million-picture-per-second cameras were blind most of the time. The solution here was to alter an existing camera design so that two modified cameras could be mounted around a single high-speed rotating mirror. A second problem, acquiring the necessary lenses of precisely specified focal lengths, was solved by obtaining a large number of production lenses from war surplus salvage. A third hurdle to be overcome was to test the new camera at an A-bomb explosion. Finally, it was necessary to solve the almost impossible difficulty of building a safe camera shelter close to a megaton explosion. This paper describes the way these problems were solved. Unfortunately the successful pictures that were taken are sill classified.

  20. High-speed photography of the first hydrogen-bomb explosion

    SciTech Connect

    Brixner, B.

    1992-01-01

    Obtaining detailed photographs of the early stages of the first hydrogen bomb explosion in 1952 posed a number of problems. First, it was necessary to invent a continuous-access camera which could solve the problem that existing million-picture-per-second cameras were blind most of the time. The solution here was to alter an existing camera design so that two modified cameras could be mounted around a single high-speed rotating mirror. A second problem, acquiring the necessary lenses of precisely specified focal lengths, was solved by obtaining a large number of production lenses from war surplus salvage. A third hurdle to be overcome was to test the new camera at an A-bomb explosion. Finally, it was necessary to solve the almost impossible difficulty of building a safe camera shelter close to a megaton explosion. This paper describes the way these problems were solved. Unfortunately the successful pictures that were taken are sill classified.

  1. Transmission electron microscopy and x-ray diffraction studies of the detonation soot of high explosives

    NASA Astrophysics Data System (ADS)

    Kashkarov, A. O.; Pruuel, E. R.; Ten, K. A.; Rubtsov, I. A.; Gerasimov, E. Yu; Zubkov, P. I.

    2016-11-01

    This paper presents the results of electron microscopy and x-ray diffraction studies of the recovered carbonaceous residue (soot) from the detonation of some high explosives: TNT, a mixture of TNT and RDX (50/50), benzotrifuroxane, and triaminotrinitrobenzene. The use of the same experimental setup allowed a qualitative and quantitative comparison of the detonation products formed under similar conditions. The results clearly show differences in the morphology of graphite-like and diamond inclusions and in the quantitative content of nanodiamonds for the explosives used in this study.

  2. HALFTON: A high-explosive containment experiment in partially saturated tuff

    SciTech Connect

    Smith, C.W.

    1996-03-01

    The HALFTON experiment explored the phenomena of high explosive detonations in 90% water-saturated tuff rock. The explosive source was a 453 kg TNT sphere which was grouted in a drift in G Tunnel, Nevada Test Site. Active gages measured stresses and motions in the range of 1.3 to 5.3 cavity radii and showed a peak stress decay as range raised to the {minus}2.77 power. Additional stress gages were fielded to investigate the gage inclusion problem.

  3. High-speed imaging, acoustic features, and aeroacoustic computations of jet noise from Strombolian (and Vulcanian) explosions

    NASA Astrophysics Data System (ADS)

    Taddeucci, J.; Sesterhenn, J.; Scarlato, P.; Stampka, K.; Del Bello, E.; Pena Fernandez, J. J.; Gaudin, D.

    2014-05-01

    High-speed imaging of explosive eruptions at Stromboli (Italy), Fuego (Guatemala), and Yasur (Vanuatu) volcanoes allowed visualization of pressure waves from seconds-long explosions. From the explosion jets, waves radiate with variable geometry, timing, and apparent direction and velocity. Both the explosion jets and their wave fields are replicated well by numerical simulations of supersonic jets impulsively released from a pressurized vessel. The scaled acoustic signal from one explosion at Stromboli displays a frequency pattern with an excellent match to those from the simulated jets. We conclude that both the observed waves and the audible sound from the explosions are jet noise, i.e., the typical acoustic field radiating from high-velocity jets. Volcanic jet noise was previously quantified only in the infrasonic emissions from large, sub-Plinian to Plinian eruptions. Our combined approach allows us to define the spatial and temporal evolution of audible jet noise from supersonic jets in small-scale volcanic eruptions.

  4. A rapid method for the identification of nitrocellulose in high explosives and smokeless powders using GC-EI-MS.

    PubMed

    Chajistamatiou, Aikaterini S; Bakeas, Evangelos B

    2016-05-01

    Nitrocellulose (NC) is one of the most common ingredients in explosive mixtures, however because of its non-volatility, its detection using Gas Chromatography-Electron Ionization-Mass Spectrometry (GC-EI-MS) has not been achieved until today. A rapid method for the identification of NC in bulk explosives using GC-EI-MS was developed. The sample preparation is simple and takes place in a test tube, employing standard equipment of a forensics laboratory. The protocol was optimized and applied to seven, both high and low, commercial explosives, which contained the substance of interest. Moreover, three explosives in the absence of NC were tested to cross check for false positives. Fourteen different standard explosive substances that are usually found in explosive mixtures were then employed in order to monitor the effect of the method on these compounds and check for interferences. Results showed that NC was detected, by its trimethylsilyl (TMS) derivatives, in all the explosive mixtures analyzed and no false positives were observed. The proposed method showed selectivity for NC, as it had no interference coming from other ingredients of explosive mixtures. The protocol introduced offers considerable improvement in identifying the individual components of an explosive mixture and contributes in successful classification of explosives. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. A Constitutive Model for Long Time Duration Mechanical Behavior in Insensitive High Explosives

    SciTech Connect

    Darnell, I M; Oh, S; Hrousis, C A; Cunningham, B J; Gagliardi, F J

    2010-03-09

    An anisotropic constitutive model for the long term dimensional stability of insensitive high explosives is proposed. Elastic, creep, thermal, and ratchet growth strains are developed. Pressure and temperature effects are considered. The constitutive model is implemented in an implicit finite element code and compared to a variety of experimental data.

  6. Trace detection of explosives using an in-line high-volume sampler, preconcentrator, and Fido explosives detector

    NASA Astrophysics Data System (ADS)

    Ingram, Russ; Sikes, John

    2010-04-01

    This paper shall demonstrate the results of a prototype system to detect explosive objects and obscured contaminated targets. By combining a high volume sampling nozzle with an inline 2-stage preconcentrator and a Fido, greater standoff is achieved than with the Fido alone. The direct application of this system is on the Autonomous Mine Detection System (AMDS) but could be deployed on a large variety of robotic platforms. It is being developed under the auspices of the U.S. Army RDECOM CERDEC Night Vision and Electronic Sensors Directorate, Countermine Division. This device is one of several detection tools and technologies to be used on the AMDS. These systems will have multiple, and at times, overlapping objectives. One objective is trace detection on the surface of an unknown potential target. By increasing the standoff capabilities of the detector, the fine manipulation of the robot deploying the detector is less critical. Current detectors used on robotic systems must either be directly in the vapor plume or make direct contact with the target. By increasing the standoff, detection is more easily and quickly achieved. The end result detector must overcome cross-contamination, sample throughput, and environmental issues. The paper will provide preliminary results of the prototype system to include data, and where feasible, video of testing results.

  7. MEKC-UV as an effective tool for the separation and identification of explosives, high explosives, and their degradation products in environmental samples.

    PubMed

    Copper, Christine; Brensinger, Karen; Rollman, Christopher; Clark, Alexis; Perez, Marlene; Genzman, Ashton; Rine, Jacqueline; Moini, Mehdi

    2016-10-01

    MEKC has been used in conjunction with UV detection for identification and quantitation of high explosives in environmental samples. To ensure the compatibility of the technique with ESI-MS, perfluorooctanoic acid (PFOA), a volatile micelle, was used. Separation of EPA Method 8330 Mixes A and B using various concentrations of the micelle showed that the 80 mM solution of PFOA was the optimum concentration for the separation of the explosives. MEKC analysis of explosives with ESI-MS under optimum micelle concentration provided excellent results indicating the compatibility of the method with ESI-MS. Finally, the MEKC-UV method was applied to the detection and quantitation of explosives in various environmental samples including water, sand, and soil. The results demonstrate that the MEKC method described herein is a viable technique for detection of explosives in environmental samples using UV detection, while maintaining the compatibility of the technique with MS detection without any modification to the separation method, if laboratories decided to pursue this route in the future. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Calculating the dynamics of High Explosive Violent Response (HEVR) after ignition

    SciTech Connect

    Reaugh, J E

    2008-10-15

    We are developing models to describe the circumstances when molecular and composite explosives undergo a rapid release of energy without detonating, and to describe the evolution of the energy release. The models also apply to the behavior of rocket propellants subject to mechanical insult, whether for accidents (Hazards) or the suite of standardized tests used to assess whether the system can be designated an Insensitive Munition (IM). In the applications described here, we are studying a UK-developed HMX (1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane) explosive, which is 91% by weight HMX and 9% binder-plasticizer. Most explosives and propellants, when subjected to a mechanical insult such as a drop or impact that is well below the threshold for detonation, have been observed to react. In some circumstances the reaction can be violent. This behavior is known as High Explosive Violent Response (HEVR). Fundamental to our model is the observation that the mechanical insult produces damage in a volume of the explosive near the trajectory of the impactor. The damage is manifest as surface area through the creation of cracks and fragments, and also as porosity through the separation of crack faces and isolation of the fragments. Open porosity permits a flame to spread easily and so ignite the newly formed surface area. The additional surface area leads to a direct increase in the mass-burning rate. As the kinetic energy and power of the insult increases, the degree of damage and the volume of damage both increase. Upon a localized ignition, the flame spreads to envelop the damaged volume, and the pressure rises at an accelerated rate until neither mechanical strength nor inertial confinement can successfully contain the pressure. The confining structure begins to expand. This reduces the pressure and may even extinguish the flame. Both the mass of explosive involved and the rate at which the gas is produced contribute to each of several different measures of violence

  9. Ion Mobility Spectrometry - High Resolution LTQ-Orbitrap Mass Spectrometry for Analysis of Homemade Explosives

    NASA Astrophysics Data System (ADS)

    Hagan, Nathan; Goldberg, Ilana; Graichen, Adam; St. Jean, Amanda; Wu, Ching; Lawrence, David; Demirev, Plamen

    2017-08-01

    The detailed chemical characterization of homemade explosives (HMEs) and other chemicals that can mimic or mask the presence of explosives is important for understanding and improving the performance of commercial instrumentation used for explosive detection. To that end, an atmospheric-pressure drift tube ion mobility spectrometry (IMS) instrument has been successfully coupled to a commercial tandem mass spectrometry (MS) system. The tandem MS system is comprised of a linear ion trap and a high resolution Orbitrap analyzer. This IMS-MS combination allows extensive characterization of threat chemical compounds, including HMEs, and complex real-world background chemicals that can interfere with detection. Here, the composition of ion species originating from a specific HME, erythritol tetranitrate, has been elucidated using accurate mass measurements, isotopic ratios, and tandem MS. Gated IMS-MS and high-resolution MS have been used to identify minor impurities that can be indicative of the HME source and/or synthesis route. Comparison between data obtained on the IMS/MS system and on commercial stand-alone IMS instruments used as explosive trace detectors (ETDs) has also been performed. Such analysis allows better signature assignments of threat compounds, modified detection algorithms, and improved overall ETD performance.

  10. Pilot-scale steam explosion pretreatment with 2-naphthol to overcome high softwood recalcitrance.

    PubMed

    Pielhop, Thomas; Amgarten, Janick; Studer, Michael H; von Rohr, Philipp Rudolf

    2017-01-01

    Steam explosion pretreatment has been examined in many studies for enhancing the enzymatic digestibility of lignocellulosic biomass and is currently the most common pretreatment method in commercial biorefineries. It is however not effective for overcoming the extremely high recalcitrance of softwood to biochemical conversion. Recent fundamental research in small-scale liquid hot water pretreatment has shown, though, that the addition of a carbocation scavenger like 2-naphthol can prevent lignin repolymerization and thus enhance the enzymatic digestibility of softwood cellulose. This work studies the technical application potential of this approach in a larger steam explosion pilot plant for surmounting softwood recalcitrance. The addition of 35.36 g 2-naphthol to the steam explosion pretreatment of 1.5 kg spruce wood chips allowed to considerably enhance the enzymatic cellulose digestibility. Different ways of adding the solid 2-naphthol to steam pretreatment were tested. Mixing with the biomass before pretreatment could enhance digestibility by up to 55% compared to control experiments. Impregnation of the biomass with 2-naphthol was yet more effective. Acetone and ethanol were tested to dissolve 2-naphthol and impregnate the biomass. The solvents were then removed again by evaporation before the pretreatment. The impregnation allowed to enhance digestibility by up to 179 and 192%, respectively. A comparison to prevalent acid-catalyzed steam explosion pretreatments for softwood revealed that the scavenger approach allows for obtaining exceptionally high yields in enzymatic hydrolysis. The biomass impregnation with 2-naphthol even renders a complete enzymatic cellulose conversion possible, which is remarkable for a softwood pretreatment not removing lignin. Steam pretreatment experiments without explosive decompression revealed that the enhancing effects of the explosion and the scavenger complement each other well. The explosion enhances the accessibility of

  11. On the quantitative measurement of fracture toughness in high explosive and mock materials

    SciTech Connect

    Liu, Cheng; Cady, Carl M; Rae, Philip J; Lovato, Manuel L

    2010-01-01

    Two approaches in measuring the fracture toughness of heterogeneous high explosives and their mocks are explored in this investigation. One is the global measurement according to the ASTM E 1820-06 standard, which is primarily developed for metallic materials to obtain quantitative measurement of parameters such as the stress intensity factor, the J-integral, and the crack-tip opening displacement (CTOD). The second approach is based on local measurements using digital image correlation (DIC). Detailed results and comparisons of the two strategies will be presented for the Mock 900-21, a mechanical simulant of the PBX 9501 high explosive. Cracking is the most dominant mechanical failure mechanism in high explosives (HE) and a key parameter for describing and predicting crack initiation and extension is the fracture toughness. Quantitative measurement of such material property poses challenges, and this is mainly because that the material is highly heterogeneous with a very complicated microstructure and the contrast of the mechanical properties of the constituents is also remarkably high. In this investigation, we explore two strategies in measuring the fracture toughness of heterogeneous high explosives and their mocks. The first approach is based on the global measurement according to the ASTM E 1820-06 standard, which is primarily developed for metallic materials to obtain quantitative measurement of parameters such as the stress intensity factor, the J-integral, and the crack-tip opening displacement (CTOD). However, there are difficulties in applying the ASTM standard on energetic solids that include identifying the moment of crack initiation and pinpointing exact crack length at each instant of time. The second approach is based on local measurements. We developed a technique for quantitatively identifying the location and extent of macroscopic cracks in heterogeneous high explosive and mock material. By combining such a technique with the displacement field

  12. On the high fidelity simulation of chemical explosions and their interaction with solid particle clouds

    NASA Astrophysics Data System (ADS)

    Balakrishnan, Kaushik

    The flow field behind chemical explosions in multiphase environments is investigated using a robust, state-of-the-art simulation strategy that accounts for the thermodynamics, gas dynamics and fluid mechanics of relevance to the problem. Focus is laid on the investigation of blast wave propagation, growth of hydrodynamic instabilities behind explosive blasts, the mixing aspects behind explosions, the effects of afterburn and its quantification, and the role played by solid particles in these phenomena. In particular, the confluence and interplay of these different physical phenomena are explored from a fundamental perspective, and applied to the problem of chemical explosions. A solid phase solver suited for the study of high-speed, two-phase flows has been developed and validated. This solver accounts for the inter-phase mass, momentum and energy transfer through empirical laws, and ensures two-way coupling between the two phases, viz. solid particles and gas. For dense flow fields, i.e., when the solid volume fraction becomes non-negligible (˜60%), the finite volume method with a Godunov type shock-capturing scheme requires modifications to account for volume fraction gradients during the computation of cell interface gas fluxes. To this end, the simulation methodology is extended with the formulation of an Eulerian gas, Lagrangian solid approach, thereby ensuring that the so developed two-phase simulation strategy can be applied for both flow conditions, dilute and dense alike. Moreover, under dense loading conditions the solid particles inevitably collide, which is accounted for in the current research effort with the use of an empirical collision/contact model from literature. Furthermore, the post-detonation flow field consists of gases under extreme temperature and pressure conditions, necessitating the use of real gas equations of state in the multiphase model. This overall simulation strategy is then extended to the investigation of chemical explosions in

  13. Low amplitude impact testing and analysis of pristine and aged solid high explosives

    SciTech Connect

    Chidester, S K; Garza, R; Tarver, C M

    1998-08-17

    The critical impact velocities of 60.1 mm diameter blunt steel projectiles required for ignition of exothermic chemical reaction were determined for heavily confined charges of new and aged (15-30 years) solid HMX-based high explosives. The explosives in order of decreasing impact sensitivity were: PBX 9404; LX-lo; LX-14; PBX 9501; and LX-04. Embedded pressure gauges measured the interior pressure histories. Stockpile aged LX-04 and PBX 9501 from dismantled units were tested and compared to freshly pressed charges. The understanding of explosive aging on impact ignition and other hazards must improve as systems are being deployed longer than their initial estimated lifetimes. The charges that did not react on the first impact were subjected to multiple impacts. While the violence of reaction increased with impact velocity, it remained much lower than that produced by an intentional detonation. Ignition and Growth reactive flow models were developed to predict HMX-based explosive impact sensitivity in other geometries and scenarios.

  14. Advances in Isentropic Compression Experiments (ICE) Using High Explosive Pulsed Power

    NASA Astrophysics Data System (ADS)

    Tasker, D. G.; Goforth, J. H.; Oona, H.; Fowler, C. M.; King, J. C.; Herrera, D.; Torres, D.

    2004-07-01

    We are developing a prototype high explosive pulsed power (HEPP) system to obtain isentropic Equation of State (EOS) data with the Asay technique. Our prototype system comprises a flat-plate explosive driven magnetic flux compression generator (FCG), an explosively formed fuse (EFF) opening switch, and a series of explosively-actuated closing switches. The FCG is capable of producing ˜10 MA into suitable loads, and, at a length of 216 mm, the EFF will sustain voltages in excess of 200 kV. The load has an inductance of ˜3 to 10 nH, allowing up to ˜7 MA to be delivered in times of ˜0.5 μs. This prototype will produce isentropic compression profiles in excess of 2 Mbar in a material such as tungsten. We will obtain isentropic EOS data for copper at pressures up to ˜1.5 Mbar with the prototype system, immediately after this conference; eventually we plan to reach several tens of Mbar with larger, more advanced systems.

  15. Development, testing and practical use of two special containment vessels for storage and transportation of high explosives

    SciTech Connect

    Dikken, H. den

    1995-12-31

    The storage and transportation of high explosives gives many logistic managers a headache, especially when it comes to forwarding of small quantities. Air transport is limited to 1.4 explosives on cargo aircraft and 1.4S classified explosives on passenger aircraft, so most samples cannot be transported by air. Ocean transport is a possibility, but due to stowage and segregation regulations of the IMDG code, a very expensive one. Road transport is often the only solution, but high explosives require special trucks with licensed drivers. The solution to these logistic problems is solved by creating a 1.4S (Class C) classification for all high explosives, when packed in special containment vessels.

  16. High-Energy-Absorbing Enclosure for Internal Explosion Containment.

    DTIC Science & Technology

    1995-06-15

    quartz fiber; ceramic fiber (e.g., silicon carbide is fiber); metallic fiber (e.g., aluminum fiber). Natural fibers such as silk or cotton or...nich completely exteriorly : nateriai; the eia"- —- - ^ "* COe££lC1Mt °f «^ ^-sion ana a tnicxness i;>.: 10 havi „„ h ’ 0t " 1SaSt °-5 inches...material, the faster it will react the load. Accordingly, conventional materials, such as metals or conventional composites, will experience very high

  17. Managing the explosion of high resolution topography in the geosciences

    NASA Astrophysics Data System (ADS)

    Crosby, Christopher; Nandigam, Viswanath; Arrowsmith, Ramon; Phan, Minh; Gross, Benjamin

    2017-04-01

    Centimeter to decimeter-scale 2.5 to 3D sampling of the Earth surface topography coupled with the potential for photorealistic coloring of point clouds and texture mapping of meshes enables a wide range of science applications. Not only is the configuration and state of the surface as imaged valuable, but repeat surveys enable quantification of topographic change (erosion, deposition, and displacement) caused by various geologic processes. We are in an era of ubiquitous point clouds that come from both active sources such as laser scanners and radar as well as passive scene reconstruction via structure from motion (SfM) photogrammetry. With the decreasing costs of high-resolution topography (HRT) data collection, via methods such as SfM and UAS-based laser scanning, the number of researchers collecting these data is increasing. These "long-tail" topographic data are of modest size but great value, and challenges exist to making them widely discoverable, shared, annotated, cited, managed and archived. Presently, there are no central repositories or services to support storage and curation of these datasets. The U.S. National Science Foundation funded OpenTopography (OT) Facility employs cyberinfrastructure including large-scale data management, high-performance computing, and service-oriented architectures, to provide efficient online access to large HRT (mostly lidar) datasets, metadata, and processing tools. With over 225 datasets and 15,000 registered users, OT is well positioned to provide curation for community collected high-resolution topographic data. OT has developed a "Community DataSpace", a service built on a low cost storage cloud (e.g. AWS S3) to make it easy for researchers to upload, curate, annotate and distribute their datasets. The system's ingestion workflow will extract metadata from data uploaded; validate it; assign a digital object identifier (DOI); and create a searchable catalog entry, before publishing via the OT portal. The OT Community

  18. Numerical Modeling of Impact Initiation of High Explosives

    SciTech Connect

    Wu, C J; Piggott, T; Yoh, J; Reaugh, J

    2006-05-31

    We performed continuum mechanics simulations to examine the behavior of energetic materials in Ballistic Chamber Impact (BIC) experiments, using an Arbitrary Lagrangian-Eulerian code (ALE3D). Our simulations revealed that interface friction plays an important role in inducing the formation of shear bands, which result in 'hot spots' for ignition. The temperature localization during BIC impact was found to be significant in materials with high yield strength. In those materials, there are multiple locations inside shear bands can achieve temperatures exceeding the threshold temperature for reaction. In addition, we investigated the relevant parameters influencing the pressure profile of a BIC test by numerical analysis from a simple phenomenological model. To our surprise, we found that the peaks of BIC pressure profiles not only can be a result of multi-center chemical reactions, but can also arise from factors associated apparatus configuration.

  19. Equation of state formulation for unreacted solid high explosive PETN

    NASA Astrophysics Data System (ADS)

    Nagayama, K.; Kubota, S.

    2017-01-01

    In this paper, a generalized procedure of providing p-v-ɛ equation of state (EOS) is developed based on the hydrostatic compression data with Birch-Murnaghan form of the isotherm. Obtained formula can be used to calculate Grüneisen EOS with arbitrary specific heat as a function of entropy, Cv(S), and arbitrary Grüneisen volume function, γ(v). It is found that different Grüneisen function gives only slight effects on EOS and p-v shock Hugoniot. On the contrary, T-v shock Hugoniot strongly depends on Cv(S) function. Constant Cv(S) gives overestimated high shock temperature TH, while linear Cv(S) gives much lower value, and intermediate function may give appropriate TH values.

  20. Progress in model development to quantify High Explosive Violent Response (HEVR) to mechancial insult

    SciTech Connect

    Reaugh, J E

    2008-07-29

    The rapid release of chemical energy has found application for industrial and military purposes since the invention of gunpowder. Black powder, smokeless powder of various compositions, and pyrotechnics all exhibit the rapid release of energy without detonation when they are being used as designed. The rapidity of energy release for these materials is controlled by adjustments to the particle surface area (propellant grain configuration or powder particle size) in conjunction with the measured pressure-dependent burning rate, which is very subsonic. In this way a manufacturing process can be used to engineer the desired violence of the explosion. Detonations in molecular explosives, in contrast, propagate with a supersonic velocity that depends on the loading density, but is independent of the surface area. In ideal detonations, the reaction is complete within a small distance of the propagating shock front. Non-ideal detonations in molecular and composite explosives proceed with a slower velocity, and the reaction may continue well behind the shock front. We are developing models to describe the circumstances when molecular and composite explosives undergo a rapid release of energy without detonating. The models also apply to the behavior of rocket propellants subject to mechanical insult, whether for accidents (Hazards) or the suite of standardized tests used to assess whether the system can be designated an Insensitive Munition (IM). In the application described here, we are studying an HMX (1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane) explosive developed in the UK, which is 91% by weight HMX and 9% binder-plasticizer. Most explosives and propellants, when subjected to a mechanical insult, drop or impact that is well below the threshold for detonation have been observed to react violently. This behavior is known as High Explosive Violent Reaction (HEVR). The basis of our model is the observation that the mechanical insult produces damage in a volume of the

  1. Modeling thermally driven energetic response of high explosives

    SciTech Connect

    Sharp, R; Couch, R; McCallen, R C; Nichols III, A L; Otero, I

    1998-02-01

    We have improved our ability to model the response of energetic materials to thermal stimuli and the processes involved in the energetic response. Traditionally, the analyses of energetic materials have involved coupled thermal transport/chemical reaction codes. This provides only a reasonable estimate of the time and location of ensuing rapid reaction. To predict the violence of the reaction, the mechanical motion must be included in the wide range of time scales associated with the thermal hazard. The ALE3D code has been modified to assess the hazards associated with heating energetic materials in weapons by coupling to thermal transport model and chemistry models. We have developed an implicit time step option to efficiently and accurately compute the hours of heating to reaction of the energetic material. Since, on these longer time scales materials can be expected to have significant motion, it is even more important to provide high-order advection for all components, including the chemical species. We show two examples of coupled thermal/mechanical/chemical models of energetic materials in thermal environments.

  2. Modeling thermally driven energetic response of high explosives

    SciTech Connect

    Couch, R; McCallen, R C; Nichols III, A L; Otero, I; Sharp, R

    1998-08-17

    We have improved our ability to model the response of energetic materials to thermal stimuli and the processes involved in the energetic response. Traditionally, the analyses of energetic materials have involved coupled thermal transport/chemical reaction codes. This provides only a reasonable estimate of the time and location of ensuing rapid reaction. To predict the violence of the reaction, the mechanical motion must be included in the wide range of time scales associated with the thermal hazard. The ALE3D code has been modified to assess the hazards associated with heating energetic materials in weapons by coupling to thermal transport model and chemistry models. We have developed an implicit time step option to efficiently and accurately compute the hours of heating to reaction of the energetic material. Since, on these longer time scales materials can be expected to have significant motion, it is even more important to provide high-order advection for all components, including the chemical species. We show two examples of coupled thermal/mechanical/chemical models of energetic materials in thermal environments.

  3. Mach stem formation in explosion systems, which include high modulus elastic elements

    NASA Astrophysics Data System (ADS)

    Balagansky, Igor A.; Hokamoto, Kazuyuki; Manikandan, Palavesamuthu; Matrosov, Alexander D.; Stadnichenko, Ivan A.; Miyoshi, Hitoshi; Bataev, Ivan A.; Bataev, Anatoly A.

    2011-12-01

    Results of experimental and numerical research of the Mach stem formation in explosion systems, which include high modulus elastic elements, are presented. The experimental data are discussed, and the analysis using ANSYS AUTODYN 11.0 is provided. It is shown that the phenomenon is reproduced for various high explosives. The Mach stem formation is observed in the conditions close to critical conditions of detonation transfer from an active to a passive HE charge. The best conditions for the Mach stem formation have been observed for TG-40/60 (Russian analog of Composition B) with silicon carbide insert heights of 16.5 mm, 18 mm, and 19.5 mm. The physical reason of the phenomenon is the propagation of a convergent detonation wave into highly compressed HE. The phenomenon is reproduced in numerical simulation with ANSYS AUTODYN 11.0. Calculated maximum value of pressure on the symmetry axis of passive HE charge was up to 1.25 Mbar. Results of metallographic analysis of steel identification specimen on the rear end of the passive HE charge indirectly confirm very high local pressures and temperatures for this scheme of explosion loading.

  4. The escape of high explosive products: An exact-solution problem for verification of hydrodynamics codes

    SciTech Connect

    Doebling, Scott William

    2016-10-22

    This paper documents the escape of high explosive (HE) products problem. The problem, first presented by Fickett & Rivard, tests the implementation and numerical behavior of a high explosive detonation and energy release model and its interaction with an associated compressible hydrodynamics simulation code. The problem simulates the detonation of a finite-length, one-dimensional piece of HE that is driven by a piston from one end and adjacent to a void at the other end. The HE equation of state is modeled as a polytropic ideal gas. The HE detonation is assumed to be instantaneous with an infinitesimal reaction zone. Via judicious selection of the material specific heat ratio, the problem has an exact solution with linear characteristics, enabling a straightforward calculation of the physical variables as a function of time and space. Lastly, implementation of the exact solution in the Python code ExactPack is discussed, as are verification cases for the exact solution code.

  5. Single and multiple impact ignition of new and aged high explosives in the Steven Impact Test

    SciTech Connect

    Chidester, S K; DePiero, A H; Garza, R G; Tarver, C M

    1999-06-01

    Threshold impact velocities for ignition of exothermic reaction were determined for several new and aged HMX-based solid high explosives using three types of projectiles in the Steven Test. Multiple impact threshold velocities were found to be approximately 10% lower in damaged charges that did not react in one or more prior impacts. Projectiles with protrusions that concentrate the friction work in a small volume of explosive reduced the threshold velocities by approximately 30%. Flat projectiles required nearly twice as high velocities for ignition as rounded projectiles. Blast overpressure gauges were used for both pristine and damaged charges to quantitatively measure reaction violence. Reactive flow calculations of single and multiple impacts with various projectiles suggest that the ignition rates double in damaged charges.

  6. Ground motion analyses: OSSY (a high explosive experiment) and MERLIN (a nuclear event)

    SciTech Connect

    Swift, R.P.

    1991-10-01

    We have analyzed recorded data and conducted numerical simulations of the seismic-calibration high explosive experiment OSSY and of the underground nuclear event MERLIN to determine if there is any physical correlation in their ground motion response. Waveforms recorded on OSSY and MERLIN show a distinct similarity in the form of a dual-pulse structure, with the second pulse as large or larger than the first pulse. Results with 1D and 2D simulations show that there is no correlation. The dual-pulse structure for OSSY can best be accounted for by a dilatancy feature resulting from pore recovery during unloading. There is also a notable influence on the pulse shape caused by the large length-to-diameter ratio of the high explosive charge. The dual-pulse structure recorded in MERLIN is most likely due to refraction from a higher-impedance layer about 60 m below the workout. 15 refs., 26 figs.

  7. Generation of Electric and Magnetic Fields During Detonation of High Explosive Charges in Boreholes

    SciTech Connect

    Soloviev, S; Sweeney, J

    2004-06-04

    We present experimental results of a study of electromagnetic field generation during underground detonation of high explosive charges in holes bored in sandy loam and granite. Test conditions and physico-mechanical properties of the soil exert significant influence on the parameters of electromagnetic signals generated by underground TNT charges with masses of 2 - 200 kg. The electric and magnetic field experimental data are satisfactorily described by an electric dipole model with the source embedded in a layered media.

  8. An improved technique of expanding metal ring experiment under high explosive loading

    NASA Astrophysics Data System (ADS)

    Tang, Tiegang; Ren, Guowu; Guo, Zhaoliang; Li, Qingzhong

    2013-04-01

    An experimental technique for metal expanding ring subjected to high explosive loading is conducted to significantly improve the loading stability compared with the traditional setup of two-end detonator initiation. Aspects of the circuit design, experimental arrangement, and initiation principle are illustrated in great detail. In terms of this experimental platform, we examine the velocity response of an individual ring, which demonstrates the experimental reproducibility. Moreover, fragmentation of multiple rings stacked on a metal driver is discussed.

  9. Hydrophone Investigations of Earthquake and Explosion Generated High-Frequency Seismic Phases.

    DTIC Science & Technology

    1986-04-30

    plates and along their subducting margins may also be similarly undetected by conventional land-based seismic stations. In this final technical report...earthquakes in the interior of the Northwestern Pacific Basin and along its subducting margins, underground explosion in the interior of ocean plates and...for Po/So frequencies as high as 30 Hz at dis- across portions of the Cocos plate , the Philip- tances in excess of 2000 km, or for So phases pine Sea

  10. Novel high-fidelity realistic explosion damage simulation for urban environments

    NASA Astrophysics Data System (ADS)

    Liu, Xiaoqing; Yadegar, Jacob; Zhu, Youding; Raju, Chaitanya; Bhagavathula, Jaya

    2010-04-01

    Realistic building damage simulation has a significant impact in modern modeling and simulation systems especially in diverse panoply of military and civil applications where these simulation systems are widely used for personnel training, critical mission planning, disaster management, etc. Realistic building damage simulation should incorporate accurate physics-based explosion models, rubble generation, rubble flyout, and interactions between flying rubble and their surrounding entities. However, none of the existing building damage simulation systems sufficiently faithfully realize the criteria of realism required for effective military applications. In this paper, we present a novel physics-based high-fidelity and runtime efficient explosion simulation system to realistically simulate destruction to buildings. In the proposed system, a family of novel blast models is applied to accurately and realistically simulate explosions based on static and/or dynamic detonation conditions. The system also takes account of rubble pile formation and applies a generic and scalable multi-component based object representation to describe scene entities and highly scalable agent-subsumption architecture and scheduler to schedule clusters of sequential and parallel events. The proposed system utilizes a highly efficient and scalable tetrahedral decomposition approach to realistically simulate rubble formation. Experimental results demonstrate that the proposed system has the capability to realistically simulate rubble generation, rubble flyout and their primary and secondary impacts on surrounding objects including buildings, constructions, vehicles and pedestrians in clusters of sequential and parallel damage events.

  11. Identification of Explosives from Porous Materials: Applications Using Reverse Phase High Performance Liquid Chromatography and Gas Chromatography

    SciTech Connect

    C.J. Miller; G. Elias; N.C. Schmitt; C. Rae

    2010-06-01

    High performance liquid chromatography and gas chromatography techniques are well documented and widely used for the detection of trace explosives from organic solvents. These techniques were modified to specifically identify and quantify explosives extracted from various materials taken from people who had recently handled explosives. Documented techniques were modified to specifically detect and quantify RDX, TNT, and PETN from denim, colored flannel, vinyl, and canvas extracted in methanol using no sample cleanup prior to analysis. The methanol extracts were injected directly into several different column types and analyzed by HPLC-UV and/or GC-ECD. This paper describes general screening methods that were used to determine the presence of explosives in unknown samples and techniques that have been optimized for quantification of each explosive from the substrate extracts.

  12. Desensitization of Heterogeneous High Explosives Under Initiation Through High Modulus Elastic Elements

    NASA Astrophysics Data System (ADS)

    Balagansky, I. A.; Glumov, A. I.; Samsonov, A. V.; Matrosov, A. D.; Stadnichenko, I. A.

    We have experimentally investigated the influence of fluoroplastic, copper, and silicon carbide inert inserts on the process of detonation transmission through water. Active and passive HE charges were molded from high explosive (HE) Comp. B. The diameter and height of HE cartridges were 40 and 40 mm, respectively. On the rear end of the passive HE charge a steel witness plate was mounted, which detected presence or absence of detonation. Inert inserts were shaped as 20 mm × 20 mm square prisms of varying lengths, and were contained between active and passive HE charges without any clearance on the way of initiating shock wave with partial overlap of HE cross sections. We demonstrate that preloading a passive HE charge with a shock wave transmitted through a copper or a ceramic insert causes considerable desensitization of the Comp. B. Other conditions being the same, the crash distance of detonation transmission for copper was equal to 74%, and for silicon carbide - to 60% of the distance for fluoroplastic. This desensitization phenomenon may be used for development of protective shells for HE. While performing experiments with 20 mm ceramic inserts we have observed unknown cumulation phenomenon, which manifested itself as a hole in identification steel specimen with depth of about 10 mm.

  13. Fiber Bragg sensing of high explosive detonation experiments at Los Alamos National Laboratory

    NASA Astrophysics Data System (ADS)

    Rodriguez, G.; Sandberg, R. L.; Jackson, S. I.; Vincent, S. W.; Gilbertson, S. M.; Udd, E.

    2014-05-01

    An all optical-fiber-based approach to measuring high explosive detonation front position and velocity is demonstrated. By measuring total light return using an incoherent light source reflected from a fiber Bragg grating sensor in contact with the explosive, dynamic mapping of the detonation front position and velocity versus time is obtained. We demonstrate two examples of detonation front measurements: PETN detasheet test and detonation along a multi-HE cylindrical rate stick containing sections of PBX 9501, Comp B, TNT, PBX 9407, PBX 9520, and inert PMMA. In the PETN detasheet measurement, excellent agreement with complementary diagnostics (electrical pins) is achieved, with accuracy in the detonation front velocity at the 0.13% level when compared to the results from the pin data.

  14. Modeling heterogeneous high explosive burn with an explicit hot-spot process

    SciTech Connect

    Tang, P.K.; Johnson, J.N.; Forest, C.A.

    1985-01-01

    We present a method of treating high explosive burn with a multi-step process which includes the hot-spot excitation, decomposition, and the propagation of reaction into the region outside the hot spots. The basic features of this model are the separation of the thermal-mechanical and chemical processes, and the partition of the explosive into hot spots and the region exclusive of the hot spots. The thermal-mechanical aspects are formulated in a way similar to the chemical process. The combined processes lead to a set of rate equations for the mass fractions of reactants, intermediate states, and final products. The rates are expressed initially in terms of general characteristic times, but with specific phenomenological correlations introduced in the final model. Computational examples are given of simulated flyer plate impacts, short-shock initiation, corner turning, and shock desensitization. 19 refs., 9 figs.

  15. Transmission and Reflection Terahertz Spectroscopy of Insensitive Melt-Cast High-Explosive Materials

    NASA Astrophysics Data System (ADS)

    Palka, Norbert; Szala, Mateusz

    2016-10-01

    Currently, artillery shells and grenades that are introduced into the market are based on melt-castable insensitive high explosives (IHEs), which do not explode while they run a risk of impact, heat or shrapnel. Particles of explosives (such as hexogen, nitroguanidine and nitrotriazolone) are suspended in different proportions in a matrix of 2.4-dinitroanisole. In this paper, we investigated samples of commonly used IHEs: PAX-41, IMX-104 and IMX-101, whose internal structures were determined by a scanning electron microscope. Terahertz time domain spectroscopy was applied in both transmission and reflection configurations. At first, the complex refraction indices of four pure constituents creating IHEs were determined and became the basis of further calculations. Next, the experimentally determined transmission and reflection spectra of IHEs and pure constituents were compared with theoretical considerations. The influence of the grain size of constituent material and scattering on the reflection spectra was analysed, and good agreement between the experimental and theoretical data was achieved.

  16. Micro- and nano- second time scale, high power electrical wire explosions in water.

    NASA Astrophysics Data System (ADS)

    Grinenko, Alon; Efimov, Sergey; Sayapin, Arkadii; Fedotov, Alexander; Gurovich, Viktor; Krasik, Yakov

    2006-10-01

    Experimental and magneto-hydro-dynamic simulation results of micro- and nanosecond time scale underwater electrical Al, Cu and W wires explosions are presented. A capacitor bank with stored energy up to 6 kJ (discharge current up to 80 kA with 2.5 μs quarter period) was used in microsecond time scale experiments and water forming line generator with current amplitude up to 100 kA and pulse duration of 100 ns were used in nanosecond time scale experiments. Extremely high energy deposition of up to 60 times the atomization enthalpy was registered in nanosecond time scale explosions. A discharge channel evolution and surface temperature were analyzed by streak shadow imaging and using fast photo-diode with a set of interference filters, respectively. Microsecond time scale electrical explosion of cylindrical wire array showed extremely high pressure of converging shock waves at the axis, up to 0.2 MBar. A 1D and 2D magneto-hydro-dynamic simulation demonstrated good agreement with such experimental parameters as discharge channel current, voltage, radius, and temperature.

  17. 3-D high-speed imaging of volcanic bomb trajectory in basaltic explosive eruptions

    USGS Publications Warehouse

    Gaudin, D.; Taddeucci, J; Houghton, B. F.; Orr, Tim R.; Andronico, D.; Del Bello, E.; Kueppers, U.; Ricci, T.; Scarlato, P.

    2016-01-01

    Imaging, in general, and high speed imaging in particular are important emerging tools for the study of explosive volcanic eruptions. However, traditional 2-D video observations cannot measure volcanic ejecta motion toward and away from the camera, strongly hindering our capability to fully determine crucial hazard-related parameters such as explosion directionality and pyroclasts' absolute velocity. In this paper, we use up to three synchronized high-speed cameras to reconstruct pyroclasts trajectories in three dimensions. Classical stereographic techniques are adapted to overcome the difficult observation conditions of active volcanic vents, including the large number of overlapping pyroclasts which may change shape in flight, variable lighting and clouding conditions, and lack of direct access to the target. In particular, we use a laser rangefinder to measure the geometry of the filming setup and manually track pyroclasts on the videos. This method reduces uncertainties to 10° in azimuth and dip angle of the pyroclasts, and down to 20% in the absolute velocity estimation. We demonstrate the potential of this approach by three examples: the development of an explosion at Stromboli, a bubble burst at Halema'uma'u lava lake, and an in-flight collision between two bombs at Stromboli.

  18. Hydrodynamic Modeling of Air Blast Propagation from the Humble Redwood Chemical High Explosive Detonations Using GEODYN

    SciTech Connect

    Chipman, V D

    2011-09-20

    Two-dimensional axisymmetric hydrodynamic models were developed using GEODYN to simulate the propagation of air blasts resulting from a series of high explosive detonations conducted at Kirtland Air Force Base in August and September of 2007. Dubbed Humble Redwood I (HR-1), these near-surface chemical high explosive detonations consisted of seven shots of varying height or depth of burst. Each shot was simulated numerically using GEODYN. An adaptive mesh refinement scheme based on air pressure gradients was employed such that the mesh refinement tracked the advancing shock front where sharp discontinuities existed in the state variables, but allowed the mesh to sufficiently relax behind the shock front for runtime efficiency. Comparisons of overpressure, sound speed, and positive phase impulse from the GEODYN simulations were made to the recorded data taken from each HR-1 shot. Where the detonations occurred above ground or were shallowly buried (no deeper than 1 m), the GEODYN model was able to simulate the sound speeds, peak overpressures, and positive phase impulses to within approximately 1%, 23%, and 6%, respectively, of the actual recorded data, supporting the use of numerical simulation of the air blast as a forensic tool in determining the yield of an otherwise unknown explosion.

  19. 3-D high-speed imaging of volcanic bomb trajectory in basaltic explosive eruptions

    NASA Astrophysics Data System (ADS)

    Gaudin, D.; Taddeucci, J.; Houghton, B. F.; Orr, T. R.; Andronico, D.; Del Bello, E.; Kueppers, U.; Ricci, T.; Scarlato, P.

    2016-10-01

    Imaging, in general, and high speed imaging in particular are important emerging tools for the study of explosive volcanic eruptions. However, traditional 2-D video observations cannot measure volcanic ejecta motion toward and away from the camera, strongly hindering our capability to fully determine crucial hazard-related parameters such as explosion directionality and pyroclasts' absolute velocity. In this paper, we use up to three synchronized high-speed cameras to reconstruct pyroclasts trajectories in three dimensions. Classical stereographic techniques are adapted to overcome the difficult observation conditions of active volcanic vents, including the large number of overlapping pyroclasts which may change shape in flight, variable lighting and clouding conditions, and lack of direct access to the target. In particular, we use a laser rangefinder to measure the geometry of the filming setup and manually track pyroclasts on the videos. This method reduces uncertainties to 10° in azimuth and dip angle of the pyroclasts, and down to 20% in the absolute velocity estimation. We demonstrate the potential of this approach by three examples: the development of an explosion at Stromboli, a bubble burst at Halema'uma'u lava lake, and an in-flight collision between two bombs at Stromboli.

  20. High-current electron gun with a planar magnetron integrated with an explosive-emission cathode

    NASA Astrophysics Data System (ADS)

    Kiziridi, P. P.; Ozur, G. E.

    2017-05-01

    A new high-current electron gun with plasma anode and explosive-emission cathode integrated with planar pulsed powered magnetron is described. Five hundred twelve copper wires 1 mm in diameter and 15 mm in height serve as emitters. These emitters are installed on stainless steel disc (substrate) with 3-mm distance between them. Magnetron discharge plasma provides increased ion density on the periphery of plasma anode formed by high-current Penning discharge ignited within several milliseconds after starting of the magnetron discharge. The increased on the periphery ion density improves the uniformity of high-current electron beam produced in such an electron gun.

  1. Nanoengineered explosives

    DOEpatents

    Makowiecki, D.M.

    1996-04-09

    A complex modulated structure is described for reactive elements that have the capability of considerably more heat than organic explosives while generating a working fluid or gas. The explosive and method of fabricating same involves a plurality of very thin, stacked, multilayer structures, each composed of reactive components, such as aluminum, separated from a less reactive element, such as copper oxide, by a separator material, such as carbon. The separator material not only separates the reactive materials, but it reacts therewith when detonated to generate higher temperatures. The various layers of material, thickness of 10 to 10,000 angstroms, can be deposited by magnetron sputter deposition. The explosive detonates and combusts a high velocity generating a gas, such as CO, and high temperatures. 2 figs.

  2. Nanoengineered explosives

    DOEpatents

    Makowiecki, Daniel M.

    1996-01-01

    A complex modulated structure of reactive elements that have the capability of considerably more heat than organic explosives while generating a working fluid or gas. The explosive and method of fabricating same involves a plurality of very thin, stacked, multilayer structures, each composed of reactive components, such as aluminum, separated from a less reactive element, such as copper oxide, by a separator material, such as carbon. The separator material not only separates the reactive materials, but it reacts therewith when detonated to generate higher temperatures. The various layers of material, thickness of 10 to 10,000 angstroms, can be deposited by magnetron sputter deposition. The explosive detonates and combusts a high velocity generating a gas, such as CO, and high temperatures.

  3. VISAR Validation Test Series at the Light Initiated High Explosive (LIHE) facility.

    SciTech Connect

    Covert, Timothy Todd

    2007-02-01

    A velocity interferometer system for any reflector (VISAR) was recently deployed at the light initiated high explosive facility (LIHE) to measure the velocity of an explosively accelerated flyer plate. The velocity data from the flyer plate experiments, using the vendor's fringe constant of 100m/s/fringe, were consistently lower than model predictions. The goal of the VISAR validation test series was to confirm the VISAR system fringe constant. A low velocity gas gun was utilized to impact and accelerate a target at the LIHE facility. VISAR velocity data from the accelerated target was compared against an independent velocity measurement. The data from this test series did in fact reveal the fringe constant was significantly higher than the vendor's specification. The correct fringe constant for the LIHE VISAR system has been determined to be 123 m/s/fringe. The Light Initiated High Explosive (LIHE) facility recently completed a Phase I test series to develop an explosively accelerated flyer plate (X-Flyer). The X-Flyer impulse technique consists of first spraying a thin layer of silver acetylide silver nitrate explosive onto a thin flyer plate. The explosive is then initiated using an intense flash of light. The explosive detonation accelerates the flyer across a small air gap towards the test item. The impact of the flyer with the test item creates a shock pulse and an impulsive load in the test unit. The goal of Phase I of the X-Flyer development series was to validate the technique theory and design process. One of the key parameters that control the shock pulse and impulsive load is the velocity of the flyer at impact. To measure this key parameter, a velocity interferometer system for any reflector (VISAR) was deployed at the LIHE facility. The VISAR system was assembled by Sandia personnel from the Explosive Projects and Diagnostics department. The VISAR was a three leg, push-pull system using a fixed delay cavity. The primary optical components consisted of

  4. Achieving High Pressure Shock Hugoniot Measurements in Cylindrical Geometry Utilizing a High-Explosive Pulsed Power Drive

    DTIC Science & Technology

    2011-06-01

    Achieving High Pressure Shock Hugoniot Measurements in Cylindrical Geometry Utilizing a High- Explosive Pulsed Power Drive J. H. Peterson Los Alamos...is used to drive a >60MA current that accelerates an aluminum liner to speeds in excess of 20 km/s. A simple circuit model is presented that models...the DEMG to reasonable accuracy and is then coupled with 1-D magnetohydrodynamic simulations of both the liner and target. 2-D hydrodynamic

  5. Characterisation and modification of thermally stable high explosives for laser flyer applications

    SciTech Connect

    Parker, A.; Claridge, R. P.; Johnson, N. A.; Proud, W. G.

    2007-12-12

    Laser initiation offers improved weapon survivability, versatility and greater Insensitive Munitions (IM) compliance. Detonators based on laser-driven flyers are less vulnerable to electrical initiation and can be based on insensitive secondary explosives. Additionally, this technology will offer advantages in terms of improved flexibility and reliability. Hexanitrostilbene (HNS) and nonanitro-m-terphenyl (NONA) were selected for investigation at QinetiQ as their increased thermal stability over conventional explosives makes them ideal candidates for use in insensitive munition compliant applications. The response of these materials to short duration high-amplitude shock impulses provided by exploding foil initiators (EFI), the electrical equivalent of a laser-driven flyer system, was investigated. Preparation techniques including sonication and the incorporation of additives were used to sensitize the materials to flyer impact, yet maintain their insensitivity to external hazards. Sonication significantly reduced the particle size of both HNS and NONA. The reduced-size explosives exhibited increased sensitivity to EFI impact than the starting materials.

  6. Explosive Line Wave Generators

    DTIC Science & Technology

    2013-12-01

    curvature produced by each line wave generator. Piezoelectric pins were used for an additional assessment of the explosive lens design...to a visual assessment of the wave curvature from the high speed camera images, the explosive lens design was also evaluated using piezoelectric pins...High Explosive Firing Complex (HEFC). The various explosive line wave generators were taped vertically on a supporting board and the detonation wave

  7. Extrusion cast explosive

    DOEpatents

    Scribner, K.J.

    1985-01-29

    Improved, multiphase, high performance, high energy, extrusion cast explosive compositions, comprising, a crystalline explosive material; an energetic liquid plasticizer; a urethane prepolymer, comprising a blend of polyvinyl formal, and polycaprolactone; a polyfunctional isocyanate; and a catalyst are disclosed. These new explosive compositions exhibit higher explosive content, a smooth detonation front, excellent stability over long periods of storage, and lower sensitivity to mechanical stimulants. 1 fig.

  8. Extrusion cast explosive

    DOEpatents

    Scribner, K.J.

    1985-11-26

    Disclosed is an improved, multiphase, high performance, high energy, extrusion cast explosive compositions, comprising, a crystalline explosive material; an energetic liquid plasticizer; a urethane prepolymer, comprising a blend of polyvinyl formal, and polycaprolactone; a polyfunctional isocyanate; and a catalyst. These new explosive compositions exhibit higher explosive content, a smooth detonation front, excellent stability over long periods of storage, and lower sensitivity to mechanical stimulants. 1 fig.

  9. High-order shock-fitted detonation propagation in high explosives

    NASA Astrophysics Data System (ADS)

    Romick, Christopher M.; Aslam, Tariq D.

    2017-03-01

    A highly accurate numerical shock and material interface fitting scheme composed of fifth-order spatial and third- or fifth-order temporal discretizations is applied to the two-dimensional reactive Euler equations in both slab and axisymmetric geometries. High rates of convergence are not typically possible with shock-capturing methods as the Taylor series analysis breaks down in the vicinity of discontinuities. Furthermore, for typical high explosive (HE) simulations, the effects of material interfaces at the charge boundary can also cause significant computational errors. Fitting a computational boundary to both the shock front and material interface (i.e. streamline) alleviates the computational errors associated with captured shocks and thus opens up the possibility of high rates of convergence for multi-dimensional shock and detonation flows. Several verification tests, including a Sedov blast wave, a Zel'dovich-von Neumann-Döring (ZND) detonation wave, and Taylor-Maccoll supersonic flow over a cone, are utilized to demonstrate high rates of convergence to nontrivial shock and reaction flows. Comparisons to previously published shock-capturing multi-dimensional detonations in a polytropic fluid with a constant adiabatic exponent (PF-CAE) are made, demonstrating significantly lower computational error for the present shock and material interface fitting method. For an error on the order of 10 m /s, which is similar to that observed in experiments, shock-fitting offers a computational savings on the order of 1000. In addition, the behavior of the detonation phase speed is examined for several slab widths to evaluate the detonation performance of PBX 9501 while utilizing the Wescott-Stewart-Davis (WSD) model, which is commonly used in HE modeling. It is found that the thickness effect curve resulting from this equation of state and reaction model using published values is dramatically more steep than observed in recent experiments. Utilizing the present fitting

  10. Exploiting high resolution Fourier transform spectroscopy to inform the development of a quantum cascade laser based explosives detection systems

    NASA Astrophysics Data System (ADS)

    Carlysle, Felicity; Nic Daeid, Niamh; Normand, Erwan; McCulloch, Michael

    2012-10-01

    Fourier Transform infrared spectroscopy (FTIR) is regularly used in forensic analysis, however the application of high resolution Fourier Transform infrared spectroscopy for the detection of explosive materials and explosive precursors has not been fully explored. This project aimed to develop systematically a protocol for the analysis of explosives and precursors using Fourier Transform infrared spectroscopy and basic data analysis to enable the further development of a quantum cascade laser (QCL) based airport detection system. This paper details the development of the protocol and results of the initial analysis of compounds of interest.

  11. Explosive laser

    DOEpatents

    Robinson, C.P.; Jensen, R.J.; Davis, W.C.; Sullivan, J.A.

    1975-09-01

    This patent relates to a laser system wherein reaction products from the detonation of a condensed explosive expand to form a gaseous medium with low translational temperature but high vibration population. Thermal pumping of the upper laser level and de-excitation of the lower laser level occur during the expansion, resulting in a population inversion. The expansion may be free or through a nozzle as in a gas-dynamic configuration. In one preferred embodiment, the explosive is such that its reaction products are CO$sub 2$ and other species that are beneficial or at least benign to CO$sub 2$ lasing. (auth)

  12. Non-detonable explosive simulators

    SciTech Connect

    Simpson, R.L.; Pruneda, C.O.

    1994-11-01

    A simulator which is chemically equivalent to an explosive, but is not detonable. The simulator has particular use in the training of explosives detecting dogs and calibrating sensitive analytical instruments. The explosive simulants may be fabricated by different techniques, a first involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and the second involves coating inert beads with thin layers of explosive molecules. 5 figs.

  13. Non-detonable explosive simulators

    SciTech Connect

    Simpson, Randall L.; Pruneda, Cesar O.

    1994-01-01

    A simulator which is chemically equivalent to an explosive, but is not detonable. The simulator has particular use in the training of explosives detecting dogs and calibrating sensitive analytical instruments. The explosive simulants may be fabricated by different techniques, a first involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and the second involves coating inert beads with thin layers of explosive molecules.

  14. Non-detonable explosive simulators

    DOEpatents

    Simpson, R.L.; Pruneda, C.O.

    1994-11-01

    A simulator which is chemically equivalent to an explosive, but is not detonable. The simulator has particular use in the training of explosives detecting dogs and calibrating sensitive analytical instruments. The explosive simulants may be fabricated by different techniques, a first involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and the second involves coating inert beads with thin layers of explosive molecules. 5 figs.

  15. Perchlorate contamination from the detonation of insensitive high-explosive rounds.

    PubMed

    Walsh, Michael R; Walsh, Marianne E; Ramsey, Charles A; Brochu, Sylvie; Thiboutot, Sonia; Ampleman, Guy

    2013-11-15

    The insensitive high-explosive PAX-21 was the first of its kind fielded in an artillery munition by the United States military. This formulation contains three main components: RDX, dinitroanisole, and ammonium perchlorate (AP). In March 2012, detonation tests were conducted on PAX-21 60mm mortar rounds to determine the energetic residues resulting from high-order and blow-in-place (BIP) detonations. Post-detonation residues were sampled and analyzed for the three main PAX-21 components. Concentrations of RDX and dinitroanisole in the samples were quite low, less than 0.1% of the munitions' original organic explosive filler mass, indicating high order or near high order detonations. However, disproportionately high concentrations of AP occurred in all residues. The residues averaged 15% of the original AP following high-order detonations and 38% of the original AP mass following the BIP operations. There was no correlation between AP residues and the RDX and dinitroanisole. Perchlorate readily leached from the detonation residues, with over 99% contained in the aqueous portion of the samples. Use of these rounds will result in billions of liters of water contaminated above drinking water perchlorate limits. As a result of this research, PAX-21 mortar rounds are currently restricted from use on US training ranges. Published by Elsevier B.V.

  16. Solving the problem of shock wave attenuation in an obstacle during a contact explosion of a high-energy material charge

    NASA Astrophysics Data System (ADS)

    Kuzin, E. N.; Zagarskih, V. I.; Efanov, V. V.

    2016-12-01

    A problem of estimation of shock wave attenuation in an obstacle under an explosion of a high-energy material (explosive) charge on its surface is considered. An algorithm for its solution is proposed using the analytical and semiempirical dependences generally recognized in explosion physics.

  17. Capabilities for high explosive pulsed power research at Los Alamos National Laboratory

    SciTech Connect

    Goforth, James H; Oona, Henn; Tasker, Douglas G; Kaul, A M

    2008-01-01

    Research on topics requiring high magnetic fields and high currents have been pursued using high explosive pulsed power (HEPP) techniques since the 1950s at Los Alamos National Laboratory. We have developed many sophisticated HEPr systems through the years, and most of them depend on technology available from the nuclear weapons program. Through the 1980s and 1990s, our budgets would sustain parallel efforts in zpinch research using both HEPr and capacitor banks. In recent years, many changes have occurred that are driven by concerns such as safety, security, and environment, as well as reduced budgets and downsizing of the National Nuclear Security Administration (NNSA) complex due to the end of the cold war era. In this paper, we review the teclmiques developed to date, and adaptations that are driven by changes in budgets and our changing complex. One new Ranchero-based solid liner z-pinch experimental design is also presented. Explosives that are cast to shape instead of being machined, and initiation systems that depend on arrays of slapper detonators are important new tools. Some materials that are seen as hazardous to the environment are avoided in designs. The process continues to allow a wide range of research however, and there are few, if any, experiments that we have done in the past that could not be perform today. The HErr firing facility at Los Alamos continues to have a 2000 lb. high explosive limit, and our 2.4 MJ capacitor bank remains a mainstay of the effort. Modem diagnostic and data analysis capabilities allow fewer personnel to achieve better results, and in the broad sense we continue to have a robust capability.

  18. Contribution of Neutron Beta Decay to Radiation Belt Pumping from High Altitude Nuclear Explosion

    SciTech Connect

    Marrs, R

    2002-11-13

    In 1962, several satellites were lost following high altitude nuclear tests by the United States and the Soviet Union. These satellite failures were caused by energetic electrons injected into the earth's radiation belts from the beta decay of bomb produced fission fragments and neutrons. It has been 40 years since the last high altitude nuclear test; there are now many more satellites in orbit, and it is important to understand their vulnerability to radiation belt pumping from nuclear explosions at high altitude or in space. This report presents the results of a calculation of the contribution of neutron beta decay to artificial belt pumping. For most high altitude nuclear explosions, neutrons are expected to make a smaller contribution than fission products to the total trapped electron inventory, and their contribution is usually neglected. However, the neutron contribution may dominate in cases where the fission product contribution is suppressed due to the altitude or geomagnetic latitude of the nuclear explosion, and for regions of the radiation belts with field lines far from the detonation point. In any case, an accurate model of belt pumping from high altitude nuclear explosions, and a self-consistent explanation of the 1962 data, require inclusion of the neutron contribution. One recent analysis of satellite measurements of electron flux from the 1962 tests found that a better fit to the data is obtained if the neutron contribution to the trapped electron inventory was larger than that of the fission products [l]. Belt pumping from high altitude nuclear explosions is a complicated process. Fission fragments are dispersed as part of the ionized bomb debris, which is constrained and guided by the earth's magnetic field. Those fission products that beta decay before being lost to the earth's atmosphere can contribute trapped energetic electrons to the earth's radiation belts. There has been a large effort to develop computer models for the contribution of

  19. Laser photoacoustic spectroscopy helps fight terrorism: High sensitivity detection of chemical Warfare Agent and explosives

    NASA Astrophysics Data System (ADS)

    Patel, C. K. N.

    2008-01-01

    Tunable laser photoacoustic spectroscopy is maturing rapidly in its applications to real world problems. One of the burning problems of the current turbulent times is the threat of terrorist acts against civilian population. This threat appears in two distinct forms. The first is the potential release of chemical warfare agents (CWA), such as the nerve agents, in a crowded environment. An example of this is the release of Sarin by Aum Shinrikyo sect in a crowded Tokyo subway in 1995. An example of the second terrorist threat is the ever-present possible suicide bomber in crowded environment such as airports, markets and large buildings. Minimizing the impact of both of these threats requires early detection of the presence of the CWAs and explosives. Photoacoustic spectroscopy is an exquisitely sensitive technique for the detection of trace gaseous species, a property that Pranalytica has extensively exploited in its CO2 laser based commercial instrumentation for the sub-ppb level detection of a number of industrially important gases including ammonia, ethylene, acrolein, sulfur hexafluoride, phosphine, arsine, boron trichloride and boron trifluoride. In this presentation, I will focus, however, on our recent use of broadly tunable single frequency high power room temperature quantum cascade lasers (QCL) for the detection of the CWAs and explosives. Using external grating cavity geometry, we have developed room temperature QCLs that produce continuously tunable single frequency CW power output in excess of 300 mW at wavelengths covering 5 μm to 12 μm. I will present data that show a CWA detection capability at ppb levels with false alarm rates below 1:108. I will also show the capability of detecting a variety of explosives at a ppb level, again with very low false alarm rates. Among the explosives, we have demonstrated the capability of detecting homemade explosives such as triacetone triperoxide and its liquid precursor, acetone which is a common household

  20. Understanding highly explosive basaltic eruptions: Evidence from olivine-hosted melt inclusions from Sunset Crater, AZ

    NASA Astrophysics Data System (ADS)

    Allison, C. M.; Roggensack, K.; Clarke, A. B.; Alfano, F.

    2013-12-01

    Basaltic scoria cone volcanoes are the most abundant volcanic landform on Earth and occur in all tectonic settings. Basaltic magmas have lower viscosities, higher temperatures, and lower volatile contents than silicic magmas, and therefore generally have a lower potential for explosive activity. However, basaltic eruptions display great variability, from mild lava flows to more energetic explosions with large plumes. The mechanism controlling highly explosive basaltic eruptions, such as the ca. 1085 AD eruption of Sunset Crater, is poorly understood. Processes or conditions such as high volatile content in the source magma, injection of a compositionally distinct magma at depth, interaction with shallow magma reservoirs, or rapid crystallization and/or bubble nucleation in the shallow subsurface could increase explosivity of basaltic magmas. One method to test these hypotheses is melt inclusion analysis in order to constrain initial melt composition, volatile content and minimum storage depth. The San Francisco Volcanic Field (SFVF) in northern Arizona, active from 6 Ma-present, consists of over 600 volcanoes - mainly alkali basalt scoria cones along with five silicic centers. The eruption of Sunset Crater in the SFVF during the Holocene was an anomalously large basaltic explosive eruption, consisting of >8 explosive phases and 3 lava flows. Typical scoria cone-forming eruptions produce <0.1 km3 DRE of material, while the Sunset Crater tephra deposit is on the order of ~0.3 km3 DRE, with each phase characterized by volumes of 0.02-0.08 km3 DRE. The phases vary in size and style; the beginning stages of explosive activity (phases 1-2) were considerably smaller than phases 3-5, classified as subplinian. Because of the young age and desert setting of the volcano, the eruptive material is fresh and the deposit is well preserved. The bulk composition is an alkali basalt with Mg# 74. We studied 40 primary melt inclusions (MIs) hosted in 36 olivine crystals 0.5-2 mm in

  1. Explosive complexes

    DOEpatents

    Huynh, My Hang V [Los Alamos, NM

    2009-09-22

    Lead-free primary explosives of the formula [M.sup.II(A).sub.R(B.sup.X).sub.S](C.sup.Y).sub.T, where A is 1,5-diaminotetrazole, and syntheses thereof are described. Substantially stoichiometric equivalents of the reactants lead to high yields of pure compositions thereby avoiding dangerous purification steps.

  2. Explosive complexes

    DOEpatents

    Huynh, My Hang V [Los Alamos, NM

    2011-08-16

    Lead-free primary explosives of the formula [M.sup.II(A).sub.R(B.sup.X).sub.S](C.sup.Y).sub.T, where A is 1,5-diaminotetrazole, and syntheses thereof are described. Substantially stoichiometric equivalents of the reactants lead to high yields of pure compositions thereby avoiding dangerous purification steps.

  3. A Review of U.S. High Explosive Pulsed Power Systems

    SciTech Connect

    Goforth, J.H.

    1998-10-18

    High explosive pulsed power (HEPP) is a specialized subset among pulsed power endeavors which takes advantage of the very high energy density available in both magnetic fields and high explosives (HE). To introduce basic concepts, the author divides HEPP components into generators (magnetic field (B) or current (I)) and switches. Magnetic field and current generators start with magnetic field trapped in a conducting volume. Magnetic flux can be expressed as either LI or BA, where L and A (inductance and cross sectional area) are both geometry dependent circuit properties. In a purely inductive circuit, flux is conserved, so L{sub 1}I{sub 1}=L{sub 2}I{sub 2} or B{sub 1}A{sub 1}=B{sub 2}A{sub 2}. In the technique, HE is used to propel circuit elements that perform work against the trapped magnetic field as L or A is reduced, yielding increased I or B. Throughout this paper, the author uses the term flux compression generator (FCG) for these devices, although the reader will find a variety of acronyms in the literature. A good primer on FCG's is by Fowler et al. HE is also used to provide opening and closing switches for HEPP circuits. Closing switches do not require great sophistication, and they don't discuss them here. Opening switches typically use the energy of HE to rapidly reduce the current carrying cross section of a particular circuit element, and often require sophisticated detonation systems to match the contour of that element (e. g. cylindrical). This may either cause a direct increase in resistance or create the circumstance in which the remainder of the material fuses due to ohmic effects. Many good papers on explosive-driven opening switches can be found in previous Megagauss conference proceedings, and these are also a good source for information regarding HEPP endeavors outside the US, which is beyond the scope of this paper.

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

    SciTech Connect

    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

  5. High power laser and explosive driven shock wave characterization in solids using fiber optic probes

    NASA Astrophysics Data System (ADS)

    Cranch, G. A.; Grün, J.; Weaver, J.; Gran, J. K.; Groethe, M. A.; Compton, S.; Fournier, K.; Dunlop, B.

    2015-09-01

    Shock wave transmission and propagation in solid media is studied using fiber optic pressure and velocity probes. Shock waves are generated in two experiments using a high power laser facility as well as conventional explosives. Shock wave properties including peak overpressure, mass velocity, shock duration, impulse, arrival time and shock velocity are characterized using fiber tip interferometric displacement sensors and Fabry-Perot pressure sensors. Measurements are conducted in polymethyl methacrylate and limestone. The probes recorded shock pressures up to 0.1 GPa (1 kbar). Measurements from the fiber optic sensors are shown to be in close agreement with measurements from an electrical sensor based on a Dremin loop.

  6. A new computer code to evaluate detonation performance of high explosives and their thermochemical properties, part I.

    PubMed

    Keshavarz, Mohammad Hossein; Motamedoshariati, Hadi; Moghayadnia, Reza; Nazari, Hamid Reza; Azarniamehraban, Jamshid

    2009-12-30

    In this paper a new simple user-friendly computer code, in Visual Basic, has been introduced to evaluate detonation performance of high explosives and their thermochemical properties. The code is based on recently developed methods to obtain thermochemical and performance parameters of energetic materials, which can complement the computer outputs of the other thermodynamic chemical equilibrium codes. It can predict various important properties of high explosive including velocity of detonation, detonation pressure, heat of detonation, detonation temperature, Gurney velocity, adiabatic exponent and specific impulse of high explosives. It can also predict detonation performance of aluminized explosives that can have non-ideal behaviors. This code has been validated with well-known and standard explosives and compared the predicted results, where the predictions of desired properties were possible, with outputs of some computer codes. A large amount of data for detonation performance on different classes of explosives from C-NO(2), O-NO(2) and N-NO(2) energetic groups have also been generated and compared with well-known complex code BKW.

  7. High explosives vapor detection by atmospheric sampling glow discharge ionization/tandem mass spectrometry

    SciTech Connect

    McLuckey, S.A.; Goeringer, D.E.; Asano, K.G.

    1996-02-01

    The combination of atmospheric sampling glow discharge ionization with tandem mass spectrometry for the detection of traces of high explosives is described. Particular emphasis is placed on use of the quadrupole ion trap as the type of tandem mass spectrometer. Atmospheric sampling glow discharge provides a simple, rugged, and efficient means for anion formation while the quadrupole ion trap provides for efficient tandem mass spectrometry. Mass selective ion accumulation and non-specific ion activation methods can be used to overcome deleterious effects arising from ion/ion interactions. Such interactions constitute the major potential technical barrier to the use of the ion trap for real-time monitoring of targeted compounds in uncontrolled and highly variable matrices. Tailored waveforms can be used to effect both mass selective ion accumulation and ion activation. Concatenated tailored waveforms allow for both functions in a single experiment thereby providing the capability for monitoring several targeted species simultaneously. The combination of atmospheric sampling glow discharge ionization with a state-of-the-art analytical quadrupole ion trap is a highly sensitive and specific detector for traces of high explosives. The combination is also small and inexpensive relative to virtually any other form of tandem mass spectrometry. The science and technology underlying the glow discharge/ion trap combination is sufficiently mature to form the basis for an engineering effort to make the detector portable. 85 refs.

  8. The Plumbing System of a Highly Explosive Basaltic Volcano: Sunset Crater, AZ

    NASA Astrophysics Data System (ADS)

    Allison, C. M.; Roggensack, K.; Clarke, A. B.

    2015-12-01

    We seek to better understand highly explosive basaltic eruptions with specific focus on magmatic volatile solubility in alkali basalts and the magma plumbing system. Sunset Crater, an alkali basalt (~3.7 wt.% alkalis) scoria cone volcano, erupted explosively in 1085 AD. We analyzed 125 primary melt inclusions (MIs) from Sunset Crater tephra deposited by 2 subplinian phases and 1 Strombolian explosion to compare magma volatiles and storage conditions. We picked rapidly quenched free olivine crystals and selected large volume MIs (50-180 μm) located toward crystal cores. MIs are faceted and exhibit little major element composition variability with minor post entrapment crystallization (2-10%). MIs are relatively dry but CO2-rich. Water content varies from 0.4 wt.% to 1.5 wt.% while carbon dioxide abundance ranges between 1,150 ppm and 3,250 ppm. Most MIs contain >1 wt.% H2O and >2,150 ppm CO2. All observed MIs contain a vapor bubble, so we are evaluating MI vapor bubbles with Raman spectroscopy and re-homogenization experiments to determine the full volatile budget. Because knowledge of volatile solubility is critical to accurately interpret results from MI analyses, we measured H2O-CO2 solubility in the Sunset Crater bulk composition. Fluid-saturated experiments at 4 and 6 kbar indicate shallower entrapment pressures for these MIs than values calculated for this composition using existing models. Assuming fluid saturation, MIs record depths from 6 km to 14 km, including groupings suggesting two pauses for longer-term storage at ~6 km and ~10.5 km. We do not observe any significant differences in MIs from phases exhibiting different eruptive styles, suggesting that while a high CO2 content may drive rapid magma ascent and be partly responsible for highly explosive eruptions, shallower processes may govern the final eruptive character. To track shallow processes during magma ascent from depth of MI-entrapment up to the surface, we are examining MI re-entrants.

  9. Deflagration Behavior of HMX-Based Explosives at High Temperatures and Pressures

    SciTech Connect

    Maienschein, J L; Wardell, J F

    2003-11-20

    We report the deflagration behavior of several HMX-based explosives at pressure from 10-600 MPa and temperatures from 20-180 C. We have made laminar burn rate measurements with the LLNL High Pressure Strand Burner, in which burn wires are used to record the time-of-arrival of the burn front in the cylindrical sample as a function of pressure. The explosive samples are 6.4 mm in diameter and 63 mm long, with ten burn wires embedded at different positions in the sample. Burning on the cylindrical surface is inhibited with an epoxy layer. With this direct measurement we do not have to account for product gas equation of state or heat losses in the system, and the burn wires allow detection of irregular burning. We find that formulation details are very important to overall deflagration behavior - the presence of 10% or less by weight of binder leads to physical deconsolidation and rapid deflagration at high pressures, and a larger particle size distribution leads to slower deflagration. High temperatures have a relatively minor effect on the deflagration rate until the beta-to-delta phase transition temperature is reached, beyond which the deflagration rate increases approximately 40-fold.

  10. Deflagration of HMX-Based Explosives at High Temperatures and Pressures

    SciTech Connect

    Maienschein, J L; Wardell, J F; DeHaven, M R; Black, C K

    2004-05-12

    We measure the deflagration behavior of energetic materials at extreme conditions (up to 520K and 1 GPa) in the LLNL High Pressure Strand Burner, thereby obtaining reaction rate data for prediction of violence of thermal explosions. The apparatus provides both temporal pressure history and flame time-of-arrival information during deflagration, allowing direct calculation of deflagration rate as a function of pressure. Samples may be heated before testing. Here we report the deflagration behavior of several HMX-based explosives at pressures of 10-600 MPa and temperatures of 300-460 K. We find that formulation details are very important to overall deflagration behavior. Formulations with high binder content (>15 wt%) deflagrate smoothly over the entire pressure range regardless of particle size, with a larger particle size distribution leading to a slower reaction. The deflagration follows a power law function with the pressure exponent being unity. Formulations with lower binder content ({le} 10% or less by weight) show physical deconsolidation at pressures over 100-200 MPA, with transition to a rapid erratic deflagration 10-100 times faster. High temperatures have a relatively minor effect on the deflagration rate until the HMX {beta} {yields} {delta} phase transition occurs, after which the deflagration rate increases by more than a factor of 10.

  11. Optically powered firing system for the Procyon high explosive pulse power system

    SciTech Connect

    Earley, L.; Paul, J.; Rohlev, L.; Goforth, J.; Hall, C.R.

    1995-10-01

    An optically powered fireset has been developed for the Procyon high explosive pulsed-power generator at Los Alamos National Laboratory. The fireset was located inside this flux compression experiment where large magnetic fields are generated. No energy sources were allowed inside the experiment and no wire connections can penetrate through the wall, of the experiment because of the high magnetic fields. The flux compression was achieved with high explosives in the experiment. The fireset was used to remotely charge a 1.2 {micro}f capacitor to 6,500V and to provide a readout of the voltage on the capacitor at the control room. The capacitor was charged by using two 7W fiber coupled GaAlAs laser diodes to illuminate two fiber coupled 12V solar cells. The solar cell outputs were connected in parallel to the input of a DC-DC converter which step up a 12V to 6,500V. A voltmeter, powered by illuminating a third 12V solar cell with 1W laser diode, was used to monitor the charge on the capacitor. The voltage was measured with a divider circuit, then converted to frequency in a V-F converter and transmitted to the control room over a fiber optic link. A fiducial circuit measured the capacitor firing current and provided an optical output timing pulse.

  12. Producing high sugar concentrations from loblolly pine using wet explosion pretreatment.

    PubMed

    Rana, Diwakar; Rana, Vandana; Ahring, Birgitte K

    2012-10-01

    We present quantitative analysis of pretreatment for obtaining high conversion and release of sugars from loblolly pine. We use wet explosion (WEx): wet oxidation followed by steam explosion and enzymatic hydrolysis (EH) at high dry matter to solubilize sugars. WEx was conducted at 25% (w/w) solids in presence of oxygen at pressures 6.5-7.2 bar, temperatures 170-175°C and residence time from 20 to 22.5 min. EH of pretreated samples was performed by Cellic® Ctec2 (60 mg protein/g cellulose) and Cellic® Htec2 enzymes (10% of Ctec2) at 50°C for 72 h. At the optimal WEx condition 96% cellulose and nearly 100% hemicellulose yield were obtained. The final concentrations of monomeric sugars were 152 g/L of glucose, 67 g/L of xylose, and 67 g/L of minor sugars (galactose, arabinose and mannose). Compared to previous work WEx seems to be superior for releasing high concentrations of monomeric sugars.

  13. The application of single particle aerosol mass spectrometry for the detection and identification of high explosives and chemical warfare agents

    SciTech Connect

    Martin, Audrey Noreen

    2006-01-01

    Single Particle Aerosol Mass Spectrometry (SPAMS) was evaluated as a real-time detection technique for single particles of high explosives. Dual-polarity time-of-flight mass spectra were obtained for samples of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitro-1,3,5-triazinane (RDX), and pentaerythritol tetranitrate (PETN); peaks indicative of each compound were identified. Composite explosives, Comp B, Semtex 1A, and Semtex 1H were also analyzed, and peaks due to the explosive components of each sample were present in each spectrum. Mass spectral variability with laser fluence is discussed. The ability of the SPAMS system to identify explosive components in a single complex explosive particle (~1 pg) without the need for consumables is demonstrated. SPAMS was also applied to the detection of Chemical Warfare Agent (CWA) simulants in the liquid and vapor phases. Liquid simulants for sarin, cyclosarin, tabun, and VX were analyzed; peaks indicative of each simulant were identified. Vapor phase CWA simulants were adsorbed onto alumina, silica, Zeolite, activated carbon, and metal powders which were directly analyzed using SPAMS. The use of metal powders as adsorbent materials was especially useful in the analysis of triethyl phosphate (TEP), a VX stimulant, which was undetectable using SPAMS in the liquid phase. The capability of SPAMS to detect high explosives and CWA simulants using one set of operational conditions is established.

  14. Identification of Explosives from Porous Materials: Applications Using Reverse Phase High Performance Liquid Chromatography and Gas Chromatography

    NASA Astrophysics Data System (ADS)

    Miller, C. J.; Elias, G.; Schmitt, N. C.; Rae, C.

    2010-06-01

    High performance liquid chromatography and gas chromatography techniques are well documented and widely used for the detection of trace explosives from organic solvents. These techniques were modified to identify and quantify explosives extracted from various materials taken from people who had recently handled explosives. Documented techniques were modified to specifically detect and quantify trace levels of the military explosives, RDX, TNT, and PETN from denim, colored flannel, vinyl, and canvas extracted in methanol and filtered using no additional sample cleanup of the sample extract prior to analysis. The filtered methanol extracts were injected directly into several different column types and analyzed by high performance liquid chromatography using ultraviolet detection and/or gas chromatography using electron capture detection. This paper describes general screening methods that were used to determine the presence of explosives (RDX, TNT, and PETN) in unknown samples of denim, colored flannel, vinyl and canvas in addition to techniques that have been optimized for quantification of each explosive from the substrate extracts.

  15. Analysis of lightning-related risk in outdoor high explosive research.

    SciTech Connect

    Eisenhawer, S. W.; Bott, T. F.

    2002-01-01

    The behavior of materials at high strain rates can be studied using high explosives (HE) as an energy source. Such hydrodynamic experiments may be performed on full-scale systems, requiring kilogram quantities of HE and therefore are performed at outdoor facilities. One such facility is DARHT-the Dual-Axis Radiographic Hydrodynamic Test facility located at Los Alamos National Laboratory in northern New Mexico. DARHT is a very large flash x-ray machine. The high-intensity, short-duration x-ray pulses are beamed through the hydrodynamic experiment to an x-ray camera. Density variations in the materials produce variations in the transmitted beam that are recorded by the camera. The information in these images is used to understand the basic behavior of materials subjected to very high dynamic pressures and to evaluate the accuracy of computer codes used to model the associated phenomena.

  16. Ruminal bioremediation of the high energy melting explosive (HMX) by sheep microorganisms.

    PubMed

    Eaton, Hillary L; Murty, Lia D; Duringer, Jennifer M; Craig, A Morrie

    2014-01-01

    The ability of ruminal microorganisms to degrade octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (high melting explosive, HMX) as consortia from whole rumen fluid (WRF), and individually as 23 commercially available ruminal strains, was compared under anaerobic conditions. Compound degradation was monitored by high-performance liquid chromatography, followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) for delineation of the metabolic pathway. In WRF, 30 μM HMX was degraded to 5 μM HMX within 24 h. Metabolites consistent with m/z 149, 193 and 229 were present throughout the incubation period. We propose that peaks with an m/z of 149 and 193 are arrived at through reduction of HMX to nitroso or hydroxylamino intermediates, then direct enzymatic ring cleavage to produce these HMX derivatives. Possible structures of m/z 229 are still being investigated and require further LC-MS/MS analysis. None of the 23 ruminal strains tested were able to degrade HMX as a pure culture when grown in either a low carbon or low nitrogen basal medium over 120 h. We conclude that microorganisms from the rumen, while sometimes capable as individuals in the bioremediation of other explosives, excel as a community in the case of HMX breakdown. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  17. A link between high-speed solar wind streams and explosive extratropical cyclones

    NASA Astrophysics Data System (ADS)

    Prikryl, Paul; Iwao, Koki; Muldrew, Donald B.; Rušin, Vojto; Rybanský, Milan; Bruntz, Robert

    2016-11-01

    A link between solar wind magnetic sector boundary (heliospheric current sheet) crossings by the Earth and the upper-level tropospheric vorticity was discovered in the 1970s. These results have been later confirmed but the proposed mechanisms remain controversial. Extratropical-cyclone tracks obtained from two meteorological reanalysis datasets are used in superposed epoch analysis of time series of solar wind plasma parameters and green coronal emission line intensity. The time series are keyed to times of maximum growth of explosively developing extratropical cyclones in the winter season. The new statistical evidence corroborates the previously published results (Prikryl et al., 2009). This evidence shows that explosive extratropical cyclones tend to occur after arrivals of solar wind disturbances such as high-speed solar wind streams from coronal holes when large amplitude magneto-hydrodynamic waves couple to the magnetosphere-ionosphere system. These MHD waves modulate Joule heating and/or Lorentz forcing of the high-latitude thermosphere generating medium-scale atmospheric gravity waves that propagate energy upward and downward from auroral zone through the atmosphere. At the tropospheric level, in spite of significantly reduced amplitudes, these gravity waves can provide a lift of unstable air to release the moist symmetric instability thus initiating slantwise convection and forming cloud/precipitation bands. The release of latent heat is known to provide energy for rapid development and intensification of extratropical cyclones.

  18. The escape of high explosive products: An exact-solution problem for verification of hydrodynamics codes

    DOE PAGES

    Doebling, Scott William

    2016-10-22

    This paper documents the escape of high explosive (HE) products problem. The problem, first presented by Fickett & Rivard, tests the implementation and numerical behavior of a high explosive detonation and energy release model and its interaction with an associated compressible hydrodynamics simulation code. The problem simulates the detonation of a finite-length, one-dimensional piece of HE that is driven by a piston from one end and adjacent to a void at the other end. The HE equation of state is modeled as a polytropic ideal gas. The HE detonation is assumed to be instantaneous with an infinitesimal reaction zone. Viamore » judicious selection of the material specific heat ratio, the problem has an exact solution with linear characteristics, enabling a straightforward calculation of the physical variables as a function of time and space. Lastly, implementation of the exact solution in the Python code ExactPack is discussed, as are verification cases for the exact solution code.« less

  19. In-situ Raman spectroscopy and high-speed photography of a shocked triaminotrinitrobenzene based explosive

    NASA Astrophysics Data System (ADS)

    Saint-Amans, C.; Hébert, P.; Doucet, M.; de Resseguier, T.

    2015-01-01

    We have developed a single-shot Raman spectroscopy experiment to study at the molecular level the initiation mechanisms that can lead to sustained detonation of a triaminotrinitrobenzene-based explosive. Shocks up to 30 GPa were generated using a two-stage laser-driven flyer plate generator. The samples were confined by an optical window and shock pressure was maintained for at least 30 ns. Photon Doppler Velocimetry measurements were performed at the explosive/window interface to determine the shock pressure profile. Raman spectra were recorded as a function of shock pressure and the shifts of the principal modes were compared to static high-pressure measurements performed in a diamond anvil cell. Our shock data indicate the role of temperature effects. Our Raman spectra also show a progressive extinction of the signal which disappears around 9 GPa. High-speed photography images reveal a simultaneous progressive darkening of the sample surface up to total opacity at 9 GPa. Reflectivity measurements under shock compression show that this opacity is due to a broadening of the absorption spectrum over the entire visible region.

  20. In-situ Raman spectroscopy and high-speed photography of a shocked triaminotrinitrobenzene based explosive

    SciTech Connect

    Saint-Amans, C.; Hébert, P. Doucet, M.; Resseguier, T. de

    2015-01-14

    We have developed a single-shot Raman spectroscopy experiment to study at the molecular level the initiation mechanisms that can lead to sustained detonation of a triaminotrinitrobenzene-based explosive. Shocks up to 30 GPa were generated using a two-stage laser-driven flyer plate generator. The samples were confined by an optical window and shock pressure was maintained for at least 30 ns. Photon Doppler Velocimetry measurements were performed at the explosive/window interface to determine the shock pressure profile. Raman spectra were recorded as a function of shock pressure and the shifts of the principal modes were compared to static high-pressure measurements performed in a diamond anvil cell. Our shock data indicate the role of temperature effects. Our Raman spectra also show a progressive extinction of the signal which disappears around 9 GPa. High-speed photography images reveal a simultaneous progressive darkening of the sample surface up to total opacity at 9 GPa. Reflectivity measurements under shock compression show that this opacity is due to a broadening of the absorption spectrum over the entire visible region.

  1. Niche explosion.

    PubMed

    Normark, Benjamin B; Johnson, Norman A

    2011-05-01

    The following syndrome of features occurs in several groups of phytophagous insects: (1) wingless females, (2) dispersal by larvae, (3) woody hosts, (4) extreme polyphagy, (5) high abundance, resulting in status as economic pests, (6) invasiveness, and (7) obligate parthenogenesis in some populations. If extreme polyphagy is defined as feeding on 20 or more families of hostplants, this syndrome is found convergently in several species of bagworm moths, tussock moths, root weevils, and 5 families of scale insects. We hypothesize that extreme polyphagy in these taxa results from "niche explosion", a positive feedback loop connecting large population size to broad host range. The niche explosion has a demographic component (sometimes called the "amplification effect" in studies of pathogens) as well as a population-genetic component, due mainly to the increased effectiveness of natural selection in larger populations. The frequent origins of parthenogenesis in extreme polyphages are, in our interpretation, a consequence of this increased effectiveness of natural selection and consequent reduced importance of sexuality. The niche explosion hypothesis makes detailed predictions about the comparative genomics and population genetics of extreme polyphages and related specialists. It has a number of potentially important implications, including an explanation for the lack of observed trade-offs between generalists and specialists, a re-interpretation of the ecological correlates of parthenogenesis, and a general expectation that Malthusian population explosions may be amplified by Darwinian effects.

  2. Multiphysics Simulations of Hot-Spot Initiation in Shocked Insensitive High-Explosive

    NASA Astrophysics Data System (ADS)

    Najjar, Fady; Howard, W. M.; Fried, L. E.

    2010-11-01

    Solid plastic-bonded high-explosive materials consist of crystals with micron-sized pores embedded. Under mechanical or thermal insults, these voids increase the ease of shock initiation by generating high-temperature regions during their collapse that might lead to ignition. Understanding the mechanisms of hot-spot initiation has significant research interest due to safety, reliability and development of new insensitive munitions. Multi-dimensional high-resolution meso-scale simulations are performed using the multiphysics software, ALE3D, to understand the hot-spot initiation. The Cheetah code is coupled to ALE3D, creating multi-dimensional sparse tables for the HE properties. The reaction rates were obtained from MD Quantum computations. Our current predictions showcase several interesting features regarding hot spot dynamics including the formation of a "secondary" jet. We will discuss the results obtained with hydro-thermo-chemical processes leading to ignition growth for various pore sizes and different shock pressures.

  3. Direct hydrolysis of cellulose to glucose using ultra-high temperature and pressure steam explosion.

    PubMed

    Sasaki, Chizuru; Sumimoto, Keisuke; Asada, Chikako; Nakamura, Yoshitoshi

    2012-06-05

    Hydrolysis of two cellulosic materials, i.e. microcrystalline cellulose powder (MC) and cuprammonium rayon fiber (BEMCOT), to glucose was carried out by steam explosion treatment with ultra-high temperature and pressure steam aiming at an effective usage of unutilized cellulosic materials. 50 g of cellulosic materials were charged in a sealed reactor (2L) of the steam explosion apparatus kept at steam pressures of 50, 55, 60, and 62 atm for a steaming time of 1 min. The maximum yield of water soluble sugars, 52.8%, was obtained at a steam pressure of 62 atm and a steaming time of 1 min for MC. Furthermore, the maximum yield of water soluble sugars, 67.7%, was obtained at a steam pressure of 60 atm and a steaming time of 1 min for BEMCOT. This water soluble sugars contained 63.1% and 61.0% of glucose, respectively; they are corresponding to 33.3g and 41.0 g of glucose contained in 100g of dry steam-exploded cellulosic material.

  4. Prompt air fluorescence induced by a high-altitude nuclear explosion

    SciTech Connect

    Horak, H.G.; Collins, D.G.; Holland, R.F.; Sutherland, C.D.

    1990-12-01

    A high-altitude (>100) nuclear explosion emits a large fraction of its energy yield in the form of x rays, approximately half of which are deposited in the atmospheric layers {approximately}50--90 km, exciting prompt fluorescence. This paper examines four of the N{sub 2}{sup +} first negative bands that fluorescence strongly: {lambda}{lambda} 3914(0,0), 4278(0,1), 4709(0,2), and 5228(0,3) {Angstrom}. We developed both forward'' and backward'' Monte Carlo procedures and performed calculations using Los Alamos CRAY computers to simulate the physical problem for the variety of situations that are possible. We include the time-dependent treatment of x-ray energy deposition, both local and nonlocal excitation of fluorescence, multiple scattering and transmission of fluorescent photons with the resulting enhancement of the longer wavelength N{sub 2}{sup +} bands, and chemical reactions. A realistic atmospheric model is defined up to 800 km, including the troposphere and a Lambert reflecting ground surface with given albedo. To expedite such computations we use separate spatial meshes in which to carry out the x-ray deposition and fluorescence light scattering. Examples of our calculated results illustrate the effects of explosion yield, geometry, tropospheric scattering, ground albedo, and temperature of the fluorescing layer. 41 refs., 38 figs., 12 tabs.

  5. Computational study of 3-D hot-spot initiation in shocked insensitive high-explosive

    NASA Astrophysics Data System (ADS)

    Najjar, F. M.; Howard, W. M.; Fried, L. E.; Manaa, M. R.; Nichols, A., III; Levesque, G.

    2012-03-01

    High-explosive (HE) material consists of large-sized grains with micron-sized embedded impurities and pores. Under various mechanical/thermal insults, these pores collapse generating hightemperature regions leading to ignition. A hydrodynamic study has been performed to investigate the mechanisms of pore collapse and hot spot initiation in TATB crystals, employing a multiphysics code, ALE3D, coupled to the chemistry module, Cheetah. This computational study includes reactive dynamics. Two-dimensional high-resolution large-scale meso-scale simulations have been performed. The parameter space is systematically studied by considering various shock strengths, pore diameters and multiple pore configurations. Preliminary 3-D simulations are undertaken to quantify the 3-D dynamics.

  6. Low and high frequency instabilities in an explosion-generated-plasma and possibility of wave triplet

    NASA Astrophysics Data System (ADS)

    Malik, O. P.; Singh, Sukhmander; Malik, Hitendra K.; Kumar, A.

    2015-01-01

    An explosion-generated-plasma is explored for low and high frequency instabilities by taking into account the drift of all the plasma species together with the dust particles which are charged. The possibility of wave triplet is also discussed based on the solution of dispersion equation and synchronism conditions. High frequency instability (HFI) and low frequency instability (LFI) are found to occur in this system. LFI grows faster with the higher concentration of dust particles, whereas its growth rate goes down if the mass of the dust is higher. The ion and electron temperatures affect its growth in opposite manner and the electron temperature causes this instability to grow. In addition to the instabilities, a simple wave is also observed to propagate, whose velocity is larger for larger wave number, smaller mass of the dust and higher ion temperature.

  7. Isentropic compression of metals, at multi-megabar pressures, using high explosive pulsed power

    SciTech Connect

    Tasker, D. G.; Goforth, J. H.; King, J. C.; Martinez, E. C.; Oona, H.; Sena, F. C.; Reisman, D. B.; Cauble, R. C.

    2001-01-01

    Accurate, ultra-high pressure isentropic equation of state (EOS) data, are required for a variety of applications and materials. Asay reported a new method to obtain these data using pulsed magnetic loading on the Sandia Z-machine. Fast rising current pulses (risetimes from 100 to 30011s) at current densities exceeding many MNcm, create continuous magnetic loading up to a few Mbar. As part of a collaborative effort between the Los Alamos and Lawrence Livermore National Laboratories we are adapting our high explosive pulsed power (HEPP) methods to obtain isentropic EOS data with the Asay technique. This year we plan to obtain isentropic EOS data for copper and tantalum at pressures up to -2 Mbar; eventually we hope to reach several tens of Mbar. We will describe the design of the HEPP systems and show out attempts to obtain EOS data to date.

  8. New 100 mm Gun Assembly Installation at Lawrence Livermore National Laboratory High Explosives Applications Facility

    SciTech Connect

    Vandersall, K S; Lee, R A; Chiao, P I; Garcia, F; Travis, J O; Forbes, J W

    2003-10-28

    A new 100mm gun assembly was recently installed and tested at Lawrence Livermore National Laboratories located in the High Explosives Applications Facility (HEAF). Thiot Ingenierie performed the design of the replacement barrel, based on improvements to the initial design. This design incorporated barrel and breech sections forged from CLARM series high-strength alloys obtained from Tecphy Corporation and machined by Manufacture de Forage. Part of the improvement of the design was implementing a laser alignment system for quick and accurate barrel alignment checks. This laser is also used to align the target assembly. This paper will detail the design changes incorporated into the installation, the testing process, and future direction of research for the new gun.

  9. Preliminary experiments using light-initiated high explosive for driving thin flyer plates. [SASN

    SciTech Connect

    Benham, R.A.

    1980-02-01

    Light-initiated high explosive, silver acelytide - silver-nitrate (SASN), has been used to produce simulated x ray blow-off impulse loading on reentry vehicles to study the system structural response. SASN can be used to accelerate thin flyer plates to high terminal velocities which, in turn, can deliver a pressure pulse that can be tailored to the target material. This process is important for impulse tests where both structural and material response is desired. The theories used to calculate the dynamic state of the flyer plate prior to impact are summarized. Data from several experiments are presented which indicate that thin flyer plates can be properly accelerated and that there are predictive techniques available which are adequate to calculate the motion of the flyer plate. Recommendations are made for future study that must be undertaken to make the SASN flyer plate technique usable.

  10. Harvesting materials formed under extreme conditions: Synthesis and isolation of nanocarbons derived from detonation of high explosives

    NASA Astrophysics Data System (ADS)

    Firestone, Millicent; Ringstrand, Bryan; Huber, Rachel; Dattelbaum, Dana; Gustavson, Richard; Podlesak, David

    High explosive detonation products are primarily composed of molecular gases and solid carbon products. Recent studies have shown that the solid carbon condensate morphologies can vary depending on the high explosive and / or the pressure, temperature, or environment of the detonation. These studies have revealed, for example, unique carbon nanoparticles possessing novel morphologies, such as ones composed of hollow cores surrounded by lamellar structured graphitic shells. Despite these observations little work has been done to isolate these particles from the recovered post-detonation soot. This lack of effort to isolate and purify these products limits our understanding of their materials properties and, ultimately our ability to adapt them for useful materials. Herein, we report our recent studies directed at the production of nano-carbons through the detonation of a high explosive (e.g., composition B) under a range of experimental conditions. We further describe work directed at isolation and purification of the carbon nanoparticles.

  11. Cylindrical In-Situ Tests at Selected Nuclear and High-Explosive Test Sites

    DTIC Science & Technology

    1977-02-01

    Configuration, CIST 16 10 Explosive Rack Construction 11 Detonator/ Booster Assembly 12 Cross Section of Hole and Gage Configuration with Geological...materials. To accom- plish this objective, an explosive source consisting of 400 grain PETN primacord is detonated in a vertical, cylindrical...The hole is filled with racked 400-grain PETN deto- nating cord (Primacord) explosive at a density of 5 pounds per linear foot of hole. Two

  12. Explosively Driven Particle Fields Imaged Using a High-Speed Framing Camera and Particle Image Velocimetry

    DTIC Science & Technology

    2011-08-01

    windows were produced by the heat exchanger method (HEM) and had a 60/40 polished surface quality on the faces and a surface peak to valley (PV...of scientific and technical information exchange , and its publication does not constitute the Government’s approval or disapproval of its ideas or...explosive provides momentum and energy transfer from the explosive to the solid particles within or packed around the outer shell of the explosive

  13. Central fatigue contributes to the greater reductions in explosive than maximal strength with high-intensity fatigue.

    PubMed

    Buckthorpe, Matthew; Pain, Matthew T G; Folland, Jonathan P

    2014-07-01

    The study aimed to assess the influence of fatigue induced by repeated high-force explosive contractions on explosive and maximal isometric strength of the human knee extensors and to examine the neural and contractile mechanisms for the expected decrement. Eleven healthy untrained males completed 10 sets of voluntary maximal explosive contractions (five times 3 s, interspersed with 2 s rest). Sets were separated by 5 s, during which supramaximal twitch and octet contractions [eight pulses at 300 Hz that elicit the contractile peak rate of force development (pRFD)] were evoked. Explosive force, at specific time points, and pRFD were assessed for voluntary and evoked efforts, expressed in absolute terms and normalized to maximal/peak force. Maximal voluntary contraction force (MVCF) and peak evoked forces were also determined. Surface EMG amplitude was measured from three superficial agonists and normalized to maximal compound action potential area. By set 10, explosive force (47-52%, P < 0.001) and MVCF (42%, P < 0.001) had declined markedly. Explosive force declined more rapidly than MVCF, with lower normalized explosive force at 50 ms (29%, P = 0.038) that resulted in reduced normalized explosive force from 0 to 150 ms (11-29%, P ≤ 0.038). Neural efficacy declined by 34%, whilst there was a 15-28% reduction in quadriceps EMG amplitude during voluntary efforts (all P ≤ 0.03). There was demonstrable contractile fatigue (pRFD: octet, 27%; twitch, 66%; both P < 0.001). Fatigue reduced normalized pRFD for the twitch (21%, P = 0.001) but not the octet (P = 0.803). Fatigue exerted a more rapid and pronounced effect on explosive force than on MVCF, particularly during the initial 50 ms of contraction, which may explain the greater incidence of injuries associated with fatigue. Both neural and contractile fatigue mechanisms appeared to contribute to impaired explosive voluntary performance.

  14. Nuclear explosive safety study process

    SciTech Connect

    1997-01-01

    Nuclear explosives by their design and intended use require collocation of high explosives and fissile material. The design agencies are responsible for designing safety into the nuclear explosive and processes involving the nuclear explosive. The methodology for ensuring safety consists of independent review processes that include the national laboratories, Operations Offices, Headquarters, and responsible Area Offices and operating contractors with expertise in nuclear explosive safety. A NES Study is an evaluation of the adequacy of positive measures to minimize the possibility of an inadvertent or deliberate unauthorized nuclear detonation, high explosive detonation or deflagration, fire, or fissile material dispersal from the pit. The Nuclear Explosive Safety Study Group (NESSG) evaluates nuclear explosive operations against the Nuclear Explosive Safety Standards specified in DOE O 452.2 using systematic evaluation techniques. These Safety Standards must be satisfied for nuclear explosive operations.

  15. Enhanced mass removal due to phase explosion during high irradiance nanosecond laser ablation of silicon

    SciTech Connect

    Yoo, Jong Hyun

    2000-05-01

    The morphology of craters resulting from high irradiance laser ablation of silicon was measured using a white light interferometry microscope. The craters show a dramatic increase in their depth and volume at a certain irradiance, indicating a change in the primary mechanism for mass removal. Laser shadowgraph imaging was used to characterize and differentiate the mass ejection processes for laser irradiances above and below the threshold value. Time-resolved images show distinct features of the mass ejected at irradiances above the threshold value including the presence of micron-sized particulates; this begins at approximately 300 ~ 400 ns after the start of laser heating. The analysis of the phenomena was carried out by using two models: a thermal evaporation model and a phase explosion model. Estimation of the crater depth due to the thermally evaporated mass led to a large underestimation of the crater depth for irradiances above the threshold. Above the threshold irradiance, the possibility of phase explosion was analyzed. Two important results are the thickness of the superheated liquid layer that is close to the critical temperature and the time for vapor bubbles that are generated in the superheated liquid to achieve a critical size. After reaching the critical size, vapor bubbles can grow spontaneously resulting in a violent ejection of liquid droplets from the superheated volume. The effects of an induced transparency, i.e. of liquid silicon turning into an optically transparent liquid dielectric medium, are also introduced. The estimated time for a bubble to reach the critical size is in agreement with the delay time measured for the initiation of large mass ejection. Also, the thickness of the superheated liquid layer that is close to the critical temperature at the time of the beginning of the large mass ejection is representative of the crater depth at the threshold irradiance. These results suggest that phase explosion is a plausible thermal

  16. Development and applications of rectangular box-type explosively bonded structures for high-heat-load beamline components

    NASA Astrophysics Data System (ADS)

    Shu, D.; Chang, J.; Kuzay, T. M.; Brasher, D. G.

    2001-07-01

    Explosive bonding technology is a good choice to join dissimilar materials, such as 304L stainless steel and GlidCop AL-15, and is used extensively in making the advanced photon source (APS) high-heat-load beamline and front-end components. It is a bonding method in which the controlled energy of a detonating explosive is used to create a metallurgical bond between two or more similar or dissimilar materials. In recent years, special explosive bonding units with rectangular box-type joints were developed for the APS new high-heat-load beamline components. Based on this new technique, the box form of the component could be built in two halves first, then welded together. Therefore, beamline designers have more freedom to optimize the cooling surface geometry.

  17. Explosives tester

    DOEpatents

    Haas, Jeffrey S [San Ramon, CA; Howard, Douglas E [Livermore, CA; Eckels, Joel D [Livermore, CA; Nunes, Peter J [Danville, CA

    2011-01-11

    An explosives tester that can be used anywhere as a screening tool by non-technical personnel to determine whether a surface contains explosives. First and second explosives detecting reagent holders and dispensers are provided. A heater is provided for receiving the first and second explosives detecting reagent holders and dispensers.

  18. Remedial investigation of the High-Explosives (HE) Process Area, Lawrence Livermore National Laboratory Site 300

    SciTech Connect

    Crow, N.B.; Lamarre, A.L.

    1990-08-01

    This report presents the results of a Remedial Investigation (RI) to define the extent of high explosives (HE) compounds and volatile organic compounds (VOCs) found in the soil, rocks, and ground water of the HE Process Area of Lawrence Livermore National Laboratory's (LLNL) Site 300 Facility. The report evaluates potential public health environmental risks associated with these compounds. Hydrogeologic information available before February 15, 1990, is included; however, chemical analyses and water-level data are reported through March 1990. This report is intended to assist the California Regional Water Quality Control Board (RWQCB)--Central Valley Region and the US Environmental Protection Agency (EPA) in evaluating the extent of environmental contamination of the LLNL HE Process Area and ultimately in designing remedial actions. 90 refs., 20 figs., 7 tabs.

  19. Deflagration Rate Measurements of Three Insensitive High Explosives: LLM-105, TATB, and DAAF

    SciTech Connect

    Glascoe, E A; Maienschein, J L; Lorenz, K T; Tan, N; Koerner, J G

    2010-03-08

    The pressure dependent deflagration rates of LLM-105, DAAF and TATB based formulations were measured in the LLNL high pressure strand burner. The role of binder amount, explosive type, and thermal damage and their effects on the deflagration rate will be discussed. One DAAF formulation, two different formulations of LLM-105, and four formulations of TATB were studied; results indicate that binder amount and type play a minor role in the deflagration behavior. This is in sharp contrast to the HMX based formulations which strongly depend on binder amount and type. The effect of preheating these samples was considerably more dramatic. In the case of LLM-105, preheating the sample appears to have little effect on the deflagration rate. In contrast, preheating DAAF and TATB formulations causes the deflagration rate to accelerate. The thermal and mechanical properties of these formulations will be discussed in the context of their pressure and temperature dependent deflagration rates.

  20. Ultra-high speed imaging and DIC for explosive system observation.

    SciTech Connect

    Cooper, Marcia A.; Reu, Phillip L.; Miller, Timothy J.

    2010-08-01

    Digital image correlation (DIC) and the tremendous advances in optical imaging are beginning to revolutionize explosive and high-strain rate measurements. This paper presents results obtained from metallic hemispheres expanded at detonation velocities. Important aspects of sample preparation and lighting of the image will be presented that are key considerations in obtaining images for DIC with frame rates at 1-million frames/second. Quantitative measurements of the case strain rate, expansion velocity and deformation will be presented. Furthermore, preliminary estimations of the measurement uncertainty will be discussed with notes on how image noise and contrast effect the measurement of shape and displacement. The data are then compared with analytical representations of the experiment.

  1. A new LIHE (Light Initiated High Explosive) test capability for spherical targets

    SciTech Connect

    Benham, R A

    1987-01-01

    A goal of the Defense Nuclear Agency Lethality and Target Hardening (LTH-3) Program is to assess the lethality of the x-ray laser against the SDI threat entourage of boosters, post-boost vehicles (PBVs), reentry vehicles, and defense suppression weapons (DSWs). A principal characteristic of the effects of the x-ray laser on such threats is the delivery of a cosine distributed impulsive load to exposed curved surfaces of the targets. The LTH-3 program is using test and analysis techniques to investigate the structural response of models of typical targets and target components subjected to impulsive flood loads. A new capability for testing spherical targets using Light Initiated High Explosive (LIHE) is the subject of this paper. Spherical targets are of interest to LTH-3 since vulnerable pressurant, propellant, and chemical reactant storage vessels in PBVs and DSWs are likely to be generally spherical in design.

  2. Lightning Protection Certification for High Explosives Facilities at Lawrence Livermore National Laboratory

    SciTech Connect

    Clancy, T J; Brown, C G; Ong, M M; Clark, G A

    2006-01-11

    Presented here is an innovation in lighting safety certification, and a description of its implementation for high explosives processing and storage facilities at Lawrence Livermore National Laboratory. Lightning rods have proven useful in the protection of wooden structures; however, modern structures made of rebar, concrete, and the like, require fresh thinking. Our process involves a rigorous and unique approach to lightning safety for modern buildings, where the internal voltages and currents are quantified and the risk assessed. To follow are the main technical aspects of lightning protection for modern structures and these methods comply with the requirements of the National Fire Protection Association, the National Electrical Code, and the Department of Energy [1][2]. At the date of this release, we have certified over 70 HE processing and storage cells at our Site 300 facility.

  3. High-energy particle acceleration by explosive electromagnetic interaction in an accretion disk

    NASA Technical Reports Server (NTRS)

    Haswell, C. A.; Tajima, T.; Sakai, J.-I.

    1992-01-01

    By examining electromagnetic field evolution occurring in an accretion disk around a compact object, we arrive at an explosive mechanism of particle acceleration. Flux-freezing in the differentially rotating disk causes the seed and/or generated magnetic field to wrap up tightly, becoming highly sheared and locally predominantly azimuthal in orientation. We show how asymptotically nonlinear solutions for the electromagnetic fields may arise in isolated plasma blobs as a result of the driving of the fluid equations by the accretion flow. These fields are capable of rapidly accelerating charged particles from the disk. Acceleration through the present mechanism from AGN can give rise to energies beyond 10 exp 20 eV. Such a mechanism may present an explanation for the extragalactic origin of the most energetic observed cosmic rays.

  4. Numerical simulation of the explosion dynamics and energy release from high-gain ICF targets

    SciTech Connect

    MacFarlane, J.J.; Sawan, M.E.; Moses, G.A.; Wang, P.; Olson, R.E.

    1996-12-31

    Results from numerical simulations are presented describing the explosion energetics of a high-gain indirect-drive ICF target. The light ion fusion LIBRA-SP target, which consists of an x-ray driven capsule embedded in a spherical foam-filled hohlraum, is imploded using 12 prepulse and 12 full power Li beams containing a total energy of 8 MJ. Here, we report on the dynamics of the target energy release, focussing in particular on the partitioning of energy between x rays, neutrons, and target debris kinetic energy. Our results indicate that 72% and 22% of the 552 MJ yield is emitted by the target in the form of neutrons and x-rays, respectively. Calculated emergent spectra for the target neutrons and x rays are also presented. 12 refs., 5 figs., 1 tab.

  5. A thermalized ion explosion model for high energy sputtering and track registration

    NASA Technical Reports Server (NTRS)

    Seiberling, L. E.; Griffith, J. E.; Tombrello, T. A.

    1980-01-01

    A velocity spectrum of neutral sputtered particles as well as a low resolution mass spectrum of sputtered molecular ions was measured for 4.74 MeV F-19(+2) incident of UF4. The velocity spectrum is dramatically different from spectra taken with low energy (keV) bombarding ions, and is shown to be consistent with a hot plasma of atoms in thermal equilibrium inside the target. A thermalized ion explosion model is proposed for high energy sputtering which is expected to describe track formation in dielectric materials. The model is shown to be consistent with the observed total sputtering yield and the dependence of the yield on the primary ionization rate of the incident ion.

  6. A case study of a transported bromine explosion event in the Canadian high arctic

    NASA Astrophysics Data System (ADS)

    Zhao, X.; Strong, K.; Adams, C.; Schofield, R.; Yang, X.; Richter, A.; Friess, U.; Blechschmidt, A.-M.; Koo, J.-H.

    2016-01-01

    Ozone depletion events in the polar troposphere have been linked to extremely high concentrations of bromine, known as bromine explosion events (BEE). However, the optimum meteorological conditions for the occurrence of these events remain uncertain. On 4-5 April 2011, a combination of both blowing snow and a stable shallow boundary layer was observed during a BEE at Eureka, Canada (86.4°W, 80.1°N). Measurements made by a Multi-Axis Differential Optical Absorption Spectroscopy spectrometer were used to retrieve BrO profiles and partial columns. During this event, the near-surface BrO volume mixing ratio increased to ~20 parts per trillion by volume, while ozone was depleted to ~1 ppbv from the surface to 700 m. Back trajectories and Global Ozone Monitoring Experiment-2 satellite tropospheric BrO columns confirmed that this event originated from a bromine explosion over the Beaufort Sea. From 30 to 31 March, meteorological data showed high wind speeds (24 m/s) and elevated boundary layer heights (~800 m) over the Beaufort Sea. Long-distance transportation (~1800 km over 5 days) to Eureka indicated strong recycling of BrO within the bromine plume. This event was generally captured by a global chemistry-climate model when a sea-salt bromine source from blowing snow was included. A model sensitivity study indicated that the surface BrO at Eureka was controlled by both local photochemistry and boundary layer dynamics. Comparison of the model results with both ground-based and satellite measurements confirmed that the BEE observed at Eureka was triggered by transport of enhanced BrO from the Beaufort Sea followed by local production/recycling under stable atmospheric shallow boundary layer conditions.

  7. On beyond the standard model for high explosives: challenges & obstacles to surmount

    SciTech Connect

    Menikoff, Ralph Ds

    2009-01-01

    Plastic-bonded explosives (PBX) are heterogeneous materials. Nevertheless, current explosive models treat them as homogeneous materials. To compensate, an empirically determined effective burn rate is used in place of a chemical reaction rate. A significant limitation of these models is that different burn parameters are needed for applications in different regimes; for example, shock initiation of a PBX at different initial temperatures or different initial densities. This is due to temperature fluctuations generated when a heterogeneous material is shock compressed. Localized regions of high temperatures are called hot spots. They dominate the reaction for shock initiation. The understanding of hot spot generation and their subsequent evolution has been limited by the inability to measure transients on small spatial ({approx} 1 {micro}m) and small temporal ({approx} 1 ns) scales in the harsh environment of a detonation. With the advances in computing power, it is natural to try and gain an understanding of hot-spot initiation with numerical experiments based on meso-scale simulations that resolve material heterogeneities and utilize realistic chemical reaction rates. However, to capture the underlying physics correctly, such high resolution simulations will require more than fast computers with a large amount of memory. Here we discuss some of the issues that need to be addressed. These include dissipative mechanisms that generate hot spots, accurate thermal propceties for the equations of state of the reactants and products, and controlling numerical entropy error from shock impedance mismatches at material interfaces. The later can generate artificial hot spots and lead to premature reaction. Eliminating numerical hot spots is critical for shock initiation simulations due to the positive feedback between the energy release from reaction and the hydrodynamic flow.

  8. On the Stability of the Detonation Wave Front in the High Explosive Liquid Mixture Tetranitromethane/Nitrobenzene

    NASA Astrophysics Data System (ADS)

    Fedorov, A. V.; Mikhaylov, A. L.; Men'Shikh, A. V.; Nazarov, D. V.; Finyushin, S. A.; Davydov, V. A.

    2010-10-01

    We performed experimental studies on the stability of the detonation wave front in mixtures of the liquids tetranitromethane (TNM) and nitrobenzene (NB). Tetranitromethane is an oxygen-rich explosive and nitrobenzene was used as a solvent or dilutant. (NB is not classed as an explosive but as an explosive would be oxygen poor and fuel rich.) The primary diagnostic was a laser velocimetry method with high temporal resolution. Data obtained were compared with the detonation parameters of the TNM/NB mixtures. In previous experimental work [1,2] it was shown that the detonation wave front in liquid explosives may be either smooth or rough. Rough detonation fronts have been reported in nitromethane, as well as nitromethane mixed with a solvent. Smooth detonation fronts have been reported in tetranitromethane. Previously, we conducted studies on the structure of the detonation wave front in liquid explosives containing tetranitromethane [3-5]. Smooth, stable fronts were recorded in pure tetranitromethane and in a 46/54 mixture of tetranitromethane and nitromethane. A pulsating, unstable detonation wave front was recorded in a 74/26 mixture of tetranitromethane and nitrobenzene. The goal of the present work is to extend our research on the structure of the detonation wave front in mixtures of tetranitromethane diluted with less energetic nitrobenzene. To this end, the following TNM/NB mixtures were studied: 95/5, 90/10, 85/15, 80/20, 74/26, and 50/50.

  9. A Simple Relationship for the Calculation of the Gurney Velocity of High Explosives Using the BKW Thermochemical Code

    NASA Astrophysics Data System (ADS)

    Frem, Dany

    2015-04-01

    A new formula is proposed for predicting the Gurney velocity ( ? ) of pure, mixed, and aluminized high explosives at any initial density. The simple relationship uses the detonation pressure and adiabatic coefficient calculated via the BKW code using the 1,3,5-Trinitro-1,3,5-triazacyclohexane (RDX) set of parameters. For 27 explosive compositions, ? was estimated using both the new formula and three older ones, and the results of each were then compared to experimental values. It is found that the new relationship is more accurate than older ones for predicting the Gurney velocity of aluminized compositions. The root mean square (rms) deviation of the new formula is 0.04-0.05 km/s for all tested explosives.

  10. Singularities of spalling fracture of plates during synchronized initiation of a high explosive (HE) charge at several points

    SciTech Connect

    Ogorodnikov, V.A.; Ivanov, A.G.

    1984-11-01

    In cases of synchronized explosions at several points on the free charge surface, the incidence of local spalls depends on the distance between the initiation points, the thickness of the high explosive (HE) layer and the plate, and the properties of the plate material in domains with sufficiently large pressure gradients. These authors investigated free surface motion in such cases by means of pulse x-ray diffraction and a manganin pressure sensor for plates from steel, copper, and lead. Tables reveal how the strength and viscosity of the plate material can affect the nature of perturbation development.

  11. Non-detonable and non-explosive explosive simulators

    SciTech Connect

    Simpson, Randall L.; Pruneda, Cesar O.

    1997-01-01

    A simulator which is chemically equivalent to an explosive, but is not detonable or explodable. The simulator is a combination of an explosive material with an inert material, either in a matrix or as a coating, where the explosive has a high surface ratio but small volume ratio. The simulator has particular use in the training of explosives detecting dogs, calibrating analytical instruments which are sensitive to either vapor or elemental composition, or other applications where the hazards associated with explosives is undesirable but where chemical and/or elemental equivalence is required. The explosive simulants may be fabricated by different techniques. A first method involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and a second method involves coating inert substrates with thin layers of explosive.

  12. Non-detonable and non-explosive explosive simulators

    SciTech Connect

    Simpson, R.L.; Pruneda, C.O.

    1997-07-15

    A simulator which is chemically equivalent to an explosive, but is not detonable or explodable is disclosed. The simulator is a combination of an explosive material with an inert material, either in a matrix or as a coating, where the explosive has a high surface ratio but small volume ratio. The simulator has particular use in the training of explosives detecting dogs, calibrating analytical instruments which are sensitive to either vapor or elemental composition, or other applications where the hazards associated with explosives is undesirable but where chemical and/or elemental equivalence is required. The explosive simulants may be fabricated by different techniques. A first method involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and a second method involves coating inert substrates with thin layers of explosive. 11 figs.

  13. Non-detonable and non-explosive explosive simulators

    DOEpatents

    Simpson, R.L.; Pruneda, C.O.

    1997-07-15

    A simulator which is chemically equivalent to an explosive, but is not detonable or explodable is disclosed. The simulator is a combination of an explosive material with an inert material, either in a matrix or as a coating, where the explosive has a high surface ratio but small volume ratio. The simulator has particular use in the training of explosives detecting dogs, calibrating analytical instruments which are sensitive to either vapor or elemental composition, or other applications where the hazards associated with explosives is undesirable but where chemical and/or elemental equivalence is required. The explosive simulants may be fabricated by different techniques. A first method involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and a second method involves coating inert substrates with thin layers of explosive. 11 figs.

  14. Highly efficient SERS substrate for direct detection of explosive TNT using popcorn-shaped gold nanoparticle-functionalized SWCNT hybrid.

    PubMed

    Demeritte, Teresa; Kanchanapally, Rajashekhar; Fan, Zhen; Singh, Anant Kumar; Senapati, Dulal; Dubey, Madan; Zakar, Eugene; Ray, Paresh Chandra

    2012-11-07

    This paper reports for the first time the development of a large-scale SERS substrate from a popcorn-shaped gold nanoparticle-functionalized single walled carbon nanotubes hybrid thin film for the selective and highly sensitive detection of explosive TNT material at a 100 femtomolar (fM) level.

  15. Fabrication of Optical Fiber Mechanical Shock Sensors for the Los Alamos HERT (High Explosive Radio Telemetry) Project

    SciTech Connect

    P. E. Klingsporn

    2005-11-14

    This document lists the requirements for the fiber optic mechanical shock sensor for the Los Alamos HERT (High Explosive Radio Telemetry) project and provides detailed process steps for fabricating, testing, and assembling the fiber shock sensors for delivery to Los Alamos.

  16. The preparation and ethanol fermentation of high-concentration sugars from steam-explosion corn stover.

    PubMed

    Xie, Hui; Wang, Fengqin; Yin, Shuangyao; Ren, Tianbao; Song, Andong

    2015-05-01

    In the field of biofuel ethanol, high-concentration- reducing sugars made from cellulosic materials lay the foundation for high-concentration ethanol fermentation. In this study, corn stover was pre-treated in a process combining chemical methods and steam explosion; the cellulosic hydrolyzed sugars obtained by fed-batch saccharification were then used as the carbon source for high-concentration ethanol fermentation. Saccharomyces cerevisiae 1308, Angel yeast, and Issatchenkia orientalis were shake-cultured with Pachysolen tannophilus P-01 for fermentation. Results implied that the ethanol yields from the three types of mixed strains were 4.85 g/100 mL, 4.57 g/100 mL, and 5.02 g/100 mL (separately) at yield rates of 91.6, 89.3, and 92.2%, respectively. Therefore, it was inferred that shock-fermentation using mixed strains achieved a higher ethanol yield at a greater rate in a shorter fermentation period. This study provided a theoretical basis and technical guidance for the fermentation of industrial high-concentrated cellulosic ethanol.

  17. Accidental explosions

    SciTech Connect

    Medard, L.A.

    1989-01-01

    This book presents a survey of accidental explosions, their nature and their causes. It covers the physical and chemical conditions governing accidental explosions, whether in the gas phase, or in the liquid or solid state. The theoretical background of the kinetics and thermochemistry of explosions is outlined, followed by a detailed study of the explosion and detonation properties of both gas and condensed explosives. The author surveys a wide variety of substances in daily use in industry which can give rise to accidental explosions. Their properties and hazards are spelt out in detail, the discussion drawing on a long history of sometimes catastrophic accidents. Includes case studies, tables of physical and chemical data.

  18. Pressure wave measurements from thermal cook-off of an HMX based high explosive

    SciTech Connect

    Forbes, J W; Tarver, C M; Urtiew, P A; Garcia, F; Greenwood, D W; Vandersall, K S

    2000-10-10

    A better understanding of thermal cook-off is important for safe handling and storing explosive devices. A number of safety issues exist about what occurs when a cased explosive thermally cooks off. For example, violence of the events as a function of confinement are important for predictions of collateral damage. This paper demonstrates how adjacent materials can be gauged to measure the resulting pressure wave and how this wave propagates in this adjacent material. The output pulse from the thermal cook-off explosive containing fixture is of obvious interest for assessing many scenarios.

  19. Pressure Wave Measurements from Thermal Cook-Off of an HMX Based High Explosive PBX 9501

    SciTech Connect

    Garcia, F; Forbes, J W; Tarver, C M; Urtiew, P A; Greenwood, D W; Vandersall, K S

    2001-05-31

    A better understanding of thermal cook-off is important for safe handling and storing explosive devices. A number of safety issues exist about what occurs when a cased explosive thermally cooks off. For example, violence of the events as a function of confinement are important for predictions of collateral damage. This paper demonstrates how adjacent materials can be gauged to measure the resulting pressure wave and how this wave propagates in this adjacent material. The output pulse from the thermal cook-off explosive containing fixture is of obvious interest for assessing many scenarios.

  20. The Mechanisms and Dynamics of High-Energy Lava-Water Explosions

    NASA Astrophysics Data System (ADS)

    Fitch, E. P.; Fagents, S. A.

    2016-12-01

    The study of explosive interactions between surface lava flows and water can provide context for understanding explosive magma-water interactions, without the competing effects of juvenile degassing-induced fragmentation. Explosive melt-water experiments and analysis of tephra produced during natural lava-water explosions (i.e. rootless tephra) indicate that the energy release during an explosion is proportional to the abundance of ash having undergone brittle fragmentation. This "blocky" ash contributes significant energy, even if the total mass of blocky ash is small relative to coarser ejecta, making it the thermodynamic driver of the explosion. Previous work has focused on relatively low-energy lava-water explosions, with a dispersal diameter of 150 m, but cones of rootless tephra (i.e. rootless cones) range in diameter from approximately 5 to 450 m, and an increase in explosion energy generally produces a more widely dispersed cone. Therefore, in order to identify processes occurring on the higher-energy end of the spectrum, we investigated the characteristics of tephra from a cone with a diameter of 400 m. In general, we find that coarser-grained beds contain a larger total abundance of fluidal grains (i.e. molten spatter) than finer-grained beds, consistent with previous work. However, some beds display an elevated abundance of fluidal ash, independent of the mean grain size of the deposit, which may be evidence of changing mixing conditions resulting in a different explosion type. Additionally, beds of the 400 m cone contain three to six times as much blocky ash as beds of the 150 m cone having similar grain-size distributions. We interpret this result to be a product of higher-energy explosions, in which ash-scale fragmentation is the most important, energetically. However, the potential effect of lava rheology will be constrained through additional analyses of tephra morphology, vesicle sizes and shapes, in addition to more detailed analysis of tephra

  1. Quantum chemical studies on three novel 1,2,4-triazole N-oxides as potential insensitive high explosives.

    PubMed

    Wu, Qiong; Zhu, Weihua; Xiao, Heming

    2014-09-01

    Three novel explosives were designed by introducing N-oxides into 1,2,4-triazole: 1-amino-3,5-dinitro-1,2,4-triazole-2 N-oxide (ADT2NO), 1-amino-2,5-dinitro-1,2,4-triazole-3 N-oxide (ADT3NO), and 1-amino-3,5-dinitro-1,2,4-triazole-4 N-oxide (ADT4NO). Their detonation performance and sensitivity were estimated by using density functional theory and compared with some famous explosives like 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) and 1-methyl-2,4,6-trinitrobenzene (TNT). All three designed molecules are more powerful than HMX and less sensitive than TNT, indicating that ADT2NO, ADT3NO, and ADT4NO have high detonation performance as HMX and low sensitivity as TNT, making them being very valuable and may be considered as the potential candidates of insensitive high explosives. Properly introducing N-oxides into the energetic triazole derivatives can generate some superior energetic compounds with both high explosive performance and reduced sensitivity.

  2. Characterization of laser-induced plasmas as a complement to high-explosive large-scale detonations

    NASA Astrophysics Data System (ADS)

    Kimblin, Clare; Trainham, Rusty; Capelle, Gene A.; Mao, Xianglei; Russo, Richard E.

    2017-09-01

    Experimental investigations into the characteristics of laser-induced plasmas indicate that LIBS provides a relatively inexpensive and easily replicable laboratory technique to isolate and measure reactions germane to understanding aspects of high-explosive detonations under controlled conditions. Spectral signatures and derived physical parameters following laser ablation of aluminum, graphite and laser-sparked air are examined as they relate to those observed following detonation of high explosives and as they relate to shocked air. Laser-induced breakdown spectroscopy (LIBS) reliably correlates reactions involving atomic Al and aluminum monoxide (AlO) with respect to both emission spectra and temperatures, as compared to small- and large-scale high-explosive detonations. Atomic Al and AlO resulting from laser ablation and a cited small-scale study, decay within ˜10-5 s, roughly 100 times faster than the Al and AlO decay rates (˜10-3 s) observed following the large-scale detonation of an Al-encased explosive. Temperatures and species produced in laser-sparked air are compared to those produced with laser ablated graphite in air. With graphite present, CN is dominant relative to N2+. In studies where the height of the ablating laser's focus was altered relative to the surface of the graphite substrate, CN concentration was found to decrease with laser focus below the graphite surface, indicating that laser intensity is a critical factor in the production of CN, via reactive nitrogen.

  3. a Study of Phase Explosion of Metal Using High Power Nd:YAG Laser Ablation

    NASA Astrophysics Data System (ADS)

    Yoh, Jack J.; Lee, H. H.; Choi, J. H.; Lee, K. C.; Kim, K. H.

    2007-12-01

    The interaction of high-power pulsed-laser beam with metal targets in air from 1.06 μm, 5 ns, 3 J/pulse max, Nd:YAG pulsed laser is investigated together with hydrodynamic theories of laser-supported detonation (LSD) wave and multi-material reactive Euler equations. The high speed blast wave generated by the laser ablation of metal reaches maximum velocity of several thousand meters per second. The apparently similar flow conditions to those of reactive shock wave allow one to apply the equations of motion for energetic materials and to understand the explosive behavior of metal vaporization upon laser ablation. The characteristic time at which planar to spherical wave transition occurs is confirmed at low (20 mJ/pulse) to higher (200 mJ/pulse) beam intensities. The flow structure behind the leading shock wave during the early planar shock state is confirmed by the high-resolution multi-material hydrocode originally developed for shock compression of condensed matter.

  4. A study of phase explosion of metal using high power Nd:YAG laser ablation

    SciTech Connect

    Yoh, Jack J.; Lee, H. H.; Choi, J. H.; Lee, K. C.; Kim, K. H.

    2007-12-12

    The interaction of high-power pulsed-laser beam with metal targets in air from 1.06 {mu}m, 5 ns, 3 J/pulse max, Nd:YAG pulsed laser is investigated together with hydrodynamic theories of laser-supported detonation (LSD) wave and multi-material reactive Euler equations. The high speed blast wave generated by the laser ablation of metal reaches maximum velocity of several thousand meters per second. The apparently similar flow conditions to those of reactive shock wave allow one to apply the equations of motion for energetic materials and to understand the explosive behavior of metal vaporization upon laser ablation. The characteristic time at which planar to spherical wave transition occurs is confirmed at low (20 mJ/pulse) to higher (200 mJ/pulse) beam intensities. The flow structure behind the leading shock wave during the early planar shock state is confirmed by the high-resolution multi-material hydrocode originally developed for shock compression of condensed matter.

  5. Big Explosives Experimental Facility - BEEF

    ScienceCinema

    None

    2016-07-12

    The Big Explosives Experimental Facility or BEEF is a ten acre fenced high explosive testing facility that provides data to support stockpile stewardship and other national security programs. At BEEF conventional high explosives experiments are safely conducted providing sophisticated diagnostics such as high speed optics and x-ray radiography.

  6. Big Explosives Experimental Facility - BEEF

    SciTech Connect

    2014-10-31

    The Big Explosives Experimental Facility or BEEF is a ten acre fenced high explosive testing facility that provides data to support stockpile stewardship and other national security programs. At BEEF conventional high explosives experiments are safely conducted providing sophisticated diagnostics such as high speed optics and x-ray radiography.

  7. Demonstration of submersible high-throughput microfluidic immunosensors for underwater explosives detection.

    PubMed

    Adams, André A; Charles, Paul T; Deschamps, Jeffrey R; Kusterbeck, Anne W

    2011-11-15

    Significant security threats posed by highly energetic nitroaromatic compounds in aquatic environments and the demilitarization and pending cleanup of areas previously used for munitions manufacture and storage represent a challenge for less expensive, faster, and more sensitive systems capable of analyzing groundwater and seawater samples for trace levels of explosive materials. Presented here is an inexpensive high throughput microfluidic immunosensor (HTMI) platform intended for the rapid, highly selective quantitation of nitroaromatic compounds in the field. Immunoaffinity and fluorescence detection schemes were implemented in tandem on a novel microfluidic device containing 39 parallel microchannels that were 500 μm tall, 250 μm wide, and 2.54 cm long with covalently tethered antibodies that was engineered for high-throughput high-volume sample processing. The devices were produced via a combination of high precision micromilling and hot embossing. Mass transfer limitations were found in conventional microsystems and were minimized due to higher surface area to volume ratios that exceeded those possessed by conventional microdevices and capillaries. Until now, these assays were limited to maximum total volume flow rates of ~1 mL/min due in part to kinetics and high head pressures of single microchannels. In the design demonstrated here, highly parallelized microchannels afforded up to a 100-fold increase in total volume flow rate while maintaining favorable kinetic constraints for efficient antigen-antibody interaction. The assay employed total volume throughput of up to 6 mL/min while yielding signal-to-noise ratios of >15 in all cases. In addition to samples being processed up to 60 times faster than in conventional displacement-based immunoassays, the current system was capable of quantitating 0.01 ng/mL TNT samples without implementing offline preconcentration, thereby, demonstrating the ability to improve sensitivity by as much as 2 orders of magnitude

  8. Novel CE-MS technique for detection of high explosives using perfluorooctanoic acid as a MEKC and mass spectrometric complexation reagent.

    PubMed

    Brensinger, Karen; Rollman, Christopher; Copper, Christine; Genzman, Ashton; Rine, Jacqueline; Lurie, Ira; Moini, Mehdi

    2016-01-01

    To address the need for the forensic analysis of high explosives, a novel capillary electrophoresis mass spectrometry (CE-MS) technique has been developed for high resolution, sensitivity, and mass accuracy detection of these compounds. The technique uses perfluorooctanoic acid (PFOA) as both a micellar electrokinetic chromatography (MEKC) reagent for separation of neutral explosives and as the complexation reagent for mass spectrometric detection of PFOA-explosive complexes in the negative ion mode. High explosives that formed complexes with PFOA included RDX, HMX, tetryl, and PETN. Some nitroaromatics were detected as molecular ions. Detection limits in the high parts per billion range and linear calibration responses over two orders of magnitude were obtained. For proof of concept, the technique was applied to the quantitative analysis of high explosives in sand samples. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  9. A highly stable dynamic fluorescent metal-organic framework for selective sensing of nitroaromatic explosives.

    PubMed

    Gong, Yun-Nan; Jiang, Long; Lu, Tong-Bu

    2013-12-07

    A dynamic fluorescent metal-organic framework has been constructed using triphenylene-2,6,10-tricarboxylate and Tb(3+) as building blocks, which exhibits guest-responsive structural dynamism and selective sensing of nitroaromatic explosives.

  10. Study of Explosive Electron Emission from a Pin Cathode Using High Resolution Point-Projection X-Ray Radiography

    NASA Astrophysics Data System (ADS)

    Pikuz, S. A.; Shelkovenko, T. A.; Hammer, D. A.; Parkevich, E. V.; Tilikin, I. N.; Mingaleev, A. R.; Agafonov, A. V.

    2015-11-01

    Most studies of Explosive Electron Emission (EEE) are based on the idea of cathode flares developing after explosion of metal whiskers (micron scale pins) on the cathode surface. The physical state of the pin material, the spatial structure of the explosion and its origin are still a matter of conjecture. In this work we used high-resolution point projection x-ray radiography to observe micron scale pin explosion in a high-current diode. Pin cathodes made from 10-25 micron Cu or Mo wires were placed in gaps in return current circuits of hybrid X-pinches on the XP and BIN pulsers. Pin lengths were varied over a range 1-4 mm and pin-anode gaps within 0.05-3 mm. The diode current and voltage were measured. In experiments with small pin-anode gap (0.1 - 1 mm) development of an expanded dense core of the pin was observed except the pin tip with length 100-200 microns indicating significant energy deposition in the wire material. In experiments with bigger gaps there was no visible wire core expansion within the spatial resolution of the experimental technique. Work at Cornell was supported by the National Nuclear Security Administration Stewardship Sciences Academic Programs under Department of Energy Cooperative Agreement No. DE-NA0001836 and at the Lebedev Institute by the RSF grant 142200273.

  11. Implementation of algorithms to discriminate chemical/biological airbursts from high explosive airbursts utilizing acoustic signatures

    NASA Astrophysics Data System (ADS)

    Hohil, Myron E.; Desai, Sachi; Morcos, Amir

    2006-05-01

    The Army is currently developing acoustic sensor systems that will provide extended range surveillance, detection, and identification for force protection and tactical security. A network of such sensors remotely deployed in conjunction with a central processing node (or gateway) will provide early warning and assessment of enemy threats, near real-time situational awareness to commanders, and may reduce potential hazards to the soldier. In contrast, the current detection of chemical/biological (CB) agents expelled into a battlefield environment is limited to the response of chemical sensors that must be located within close proximity to the CB agent. Since chemical sensors detect hazardous agents through contact, the sensor range to an airburst is the key-limiting factor in identifying a potential CB weapon attack. The associated sensor reporting latencies must be minimized to give sufficient preparation time to field commanders, who must assess if an attack is about to occur, has occurred, or if occurred, the type of agent that soldiers might be exposed to. The long-range propagation of acoustic blast waves from heavy artillery blasts, which are typical in a battlefield environment, introduces a feature for using acoustics and other sensor suite technologies for the early detection and identification of CB threats. Employing disparate sensor technologies implies that warning of a potential CB attack can be provided to the solider more rapidly and from a safer distance when compared to current conventional methods. Distinct characteristics arise within the different airburst signatures because High Explosive (HE) warheads emphasize concussive and shrapnel effects, while chemical/biological warheads are designed to disperse their contents over immense areas, therefore utilizing a slower burning, less intensive explosion to mix and distribute their contents. Highly reliable discrimination (100%) has been demonstrated at the Portable Area Warning Surveillance System

  12. Implementation of algorithms to discriminate between chemical/biological airbursts and high explosive airbursts

    NASA Astrophysics Data System (ADS)

    Hohil, Myron E.; Desai, Sachi; Morcos, Amir

    2006-09-01

    The Army is currently developing acoustic sensor systems that will provide extended range surveillance, detection, and identification for force protection and tactical security. A network of such sensors remotely deployed in conjunction with a central processing node (or gateway) will provide early warning and assessment of enemy threats, near real-time situational awareness to commanders, and may reduce potential hazards to the soldier. In contrast, the current detection of chemical/biological (CB) agents expelled into a battlefield environment is limited to the response of chemical sensors that must be located within close proximity to the CB agent. Since chemical sensors detect hazardous agents through contact, the sensor range to an airburst is the key-limiting factor in identifying a potential CB weapon attack. The associated sensor reporting latencies must be minimized to give sufficient preparation time to field commanders, who must assess if an attack is about to occur, has occurred, or if occurred, the type of agent that soldiers might be exposed to. The long-range propagation of acoustic blast waves from heavy artillery blasts, which are typical in a battlefield environment, introduces a feature for using acoustics and other sensor suite technologies for the early detection and identification of CB threats. Employing disparate sensor technologies implies that warning of a potential CB attack can be provided to the solider more rapidly and from a safer distance when compared to current conventional methods. Distinct characteristics arise within the different airburst signatures because High Explosive (HE) warheads emphasize concussive and shrapnel effects, while chemical/biological warheads are designed to disperse their contents over immense areas, therefore utilizing a slower burning, less intensive explosion to mix and distribute their contents. Highly reliable discrimination (100%) has been demonstrated at the Portable Area Warning Surveillance System

  13. Dependence of hotspot initiation on void distribution in high explosive crystals simulated with molecular dynamics

    NASA Astrophysics Data System (ADS)

    Herring, Stuart Davis

    Microscopic defects may dramatically affect the susceptibility of high explosives to shock initiation. Such defects redirect the shock's energy and become hotspots (concentrations of stress and heat) that can initiate chemical reactions. Sufficiently large or numerous defects may produce a self-sustaining deflagration or even detonation from a shock notably too weak to detonate defect-free samples. The effects of circular or spherical voids on the shock sensitivity of a model (two- or three-dimensional) high explosive crystal are considered. We simulate a piston impact using molecular dynamics with a Reactive Empirical Bond Order (REBO) model potential for a sub-micron, sub-ns exothermic reaction in a diatomic molecular solid. In both dimensionalities, the probability of initiating chemical reactions rises more suddenly with increasing piston velocity for larger voids that collapse more deterministically. A void of even 10 nm radius (˜39 interatomic spacings) reduces the minimum initiating velocity by a factor of 4 (8 in 3D). The transition at larger velocities to detonation is studied in micron-long samples with a single void (and its periodic images). Reactions during the shock traversal increase rapidly with velocity, then become a reliable detonation. In 2D, a void of radius 2.5 nm reduces the critical velocity by 10% from the perfect crystal; a Pop plot of the detonation delays at higher velocities shows a characteristic pressure dependence. 3D samples are more likely to react but less to detonate. In square lattices of voids, reducing the (common) void radius or increasing the porosity without changing the other parameter causes the hotspots to consume the material faster and detonation to occur sooner and at lower velocities. Early behavior is seen to follow a very simple ignition and growth model; the pressure exponents are more realistic than with single voids. The hotspots collectively develop a broad pressure wave (a sonic, diffuse deflagration front

  14. Highly selective and sensitive fluorescent paper sensor for nitroaromatic explosive detection.

    PubMed

    Ma, Yingxin; Li, Hao; Peng, Shan; Wang, Leyu

    2012-10-02

    Rapid, sensitive, and selective detection of explosives such as 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenol (TNP), especially using a facile paper sensor, is in high demand for homeland security and public safety. Although many strategies have been successfully developed for the detection of TNT, it is not easy to differentiate the influence from TNP. Also, few methods were demonstrated for the selective detection of TNP. In this work, via a facile and versatile method, 8-hydroxyquinoline aluminum (Alq(3))-based bluish green fluorescent composite nanospheres were successfully synthesized through self-assembly under vigorous stirring and ultrasonic treatment. These polymer-coated nanocomposites are not only water-stable but also highly luminescent. Based on the dramatic and selective fluorescence quenching of the nanocomposites via adding TNP into the aqueous solution, a sensitive and robust platform was developed for visual detection of TNP in the mixture of nitroaromatics including TNT, 2,4-dinitrotoluene (DNT), and nitrobenzene (NB). Meanwhile, the fluorescence intensity is proportional to the concentration of TNP in the range of 0.05-7.0 μg/mL with the 3σ limit of detection of 32.3 ng/mL. By handwriting or finger printing with TNP solution as ink on the filter paper soaked with the fluorescent nanocomposites, the bluish green fluorescence was instantly and dramatically quenched and the dark patterns were left on the paper. Therefore, a convenient and rapid paper sensor for TNP-selective detection was fabricated.

  15. Sequential high gravity ethanol fermentation and anaerobic digestion of steam explosion and organosolv pretreated corn stover.

    PubMed

    Katsimpouras, Constantinos; Zacharopoulou, Maria; Matsakas, Leonidas; Rova, Ulrika; Christakopoulos, Paul; Topakas, Evangelos

    2017-11-01

    The present work investigates the suitability of pretreated corn stover (CS) to serve as feedstock for high gravity (HG) ethanol production at solids-content of 24wt%. Steam explosion, with and without the addition of H2SO4, and organosolv pretreated CS samples underwent a liquefaction/saccharification step followed by simultaneous saccharification and fermentation (SSF). Maximum ethanol concentration of ca. 76g/L (78.3% ethanol yield) was obtained from steam exploded CS (SECS) with 0.2% H2SO4. Organosolv pretreated CS (OCS) also resulted in high ethanol concentration of ca. 65g/L (62.3% ethanol yield). Moreover, methane production through anaerobic digestion (AD) was conducted from fermentation residues and resulted in maximum methane yields of ca. 120 and 69mL/g volatile solids (VS) for SECS and OCS samples, respectively. The results indicated that the implementation of a liquefaction/saccharification step before SSF employing a liquefaction reactor seemed to handle HG conditions adequately. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Standoff Raman spectrometry for the non-invasive detection of explosives precursors in highly fluorescing packaging.

    PubMed

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

    2013-01-15

    Noninvasive standoff deep Raman spectroscopy has been utilised for the detection of explosives precursors in highly fluorescing packaging from 15m. To our knowledge this is the first time standoff deep Raman spectroscopy of concealed substances in highly fluorescing coloured packaging is demonstrated. Time-resolved Raman spectroscopy, spatially offset Raman spectroscopy and time-resolved spatially offset Raman spectroscopy have been compared to identify their selectivity towards the deep layers of a sample. The selectivity of time-resolved Raman spectroscopy towards the concealed chemical substances was found to be comparable to that of spatially offset Raman spectroscopy. However, time-resolved Raman spectroscopy did not require precise translation of the laser excitation beam onto the surface of the interrogated packaging as in the case of spatially offset Raman spectroscopy. Our results confirm that standoff time-resolved spatially offset Raman spectroscopy has significantly higher selectivity towards the deep layers of a sample when compared to the other deep Raman spectroscopy modes. The developed spectrometer was capable of detecting the concealed substances within 5s of data acquisition. By using time-resolved spatially Raman spectroscopy, a Raman spectrum that is representative of the content alone was acquired without the use of sophisticated algorithms to eliminate the spectral contributions of the packaging material within the acquired spectrum as in the case of time-resolved Raman spectroscopy and spatially offset Raman spectroscopy. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Highly explosive 2010 Merapi eruption: Evidence for shallow-level crustal assimilation and hybrid fluid

    NASA Astrophysics Data System (ADS)

    Borisova, Anastassia Y.; Martel, Caroline; Gouy, Sophie; Pratomo, Indyo; Sumarti, Sri; Toutain, Jean-Paul; Bindeman, Ilya N.; de Parseval, Philippe; Metaxian, Jean-Philippe; Surono

    2013-07-01

    The processes responsible for the highly explosive events at Merapi, Central Java, Indonesia have been investigated through a petrological, mineralogical and geochemical study of the first-stage tephra and pyroclastic flows sampled in October and November 2010, and second-stage ash sampled shortly after the 5-6th November 2010 paroxysmal subplinian eruption. Several chemical and physical parameters suggest that the magma assimilated calc-silicate xenoliths derived from the surrounding carbonate-bearing crust (Javanese limestone). The bulk volcanic samples have highly radiogenic 87Sr/86Sr (0.70571-0.70598) ratios that approach the compositional field of material similar to the calc-silicate xenoliths. The 2010 plagioclase phenocrysts from the pyroclastic flow and tephra reveal anorthite cores (up to An94-97) with low FeO contents (≤ 0.8 wt.%), and 18O enrichment (6.5‰ δ18O). The major and trace elements of the silicic glasses and phenocrysts (plagioclase, low-Al augite and titanomagnetite), the Sr-isotopic compositions of the bulk samples and plagioclases erupted in 2010 can be explained by complete digestion of the 1998 and 2006 calc-silicate xenoliths. The bulk assimilation proceeded through binary mixing between a calcic melt (representing Crustal Assimilant, CaO up to 10.5 wt.% and CaO/Al2O3 up to 1.2) and the deep source hydrous K-rich melt. Similarly to the 1998 and 2006 calc-silicate xenolith composition, the 2010 Crustal Assimilant is enriched in Mn (MnO up to 0.5 wt.%), Zn, V, and Sc contents. In contrast, the hydrous K-rich melt is enriched in volatiles (Cl up to 0.37 wt.% and bulk H2O + CO2 up to 5 ± 1 wt.%), Al2O3, TiO2 and REE contents, consistent with its derivation from deep source. This hydrous K-rich melt may have been saturated with an aqueous Cl-rich fluid at about 200 MPa, a pressure consistent with the level of the crustal assimilation. We estimated that the pre-eruptive basaltic andesite magma assimilated from 15 to 40 wt.% of the calc

  18. Neutralization of improvised explosive devices by high-power lasers: research results from the FP7 project ENCOUNTER

    NASA Astrophysics Data System (ADS)

    Osterholz, J.; Lueck, M.; Lexow, B.; Wickert, M.

    2016-10-01

    The development of reliable techniques for the safe neutralization of improvised explosive devices (IEDs) is an active field of research. Recently, innovative approaches for the neutralization of IEDs were developed and tested within the FP7 project ENCOUNTER ("Explosive Neutralisation and Mitigation Countermeasures for IEDs in Urban/Civil Environment") and were compared to existing, established technologies. Here, the ENCOUNTER project is presented with a special focus on the neutralization of IEDs by high-power lasers. The working principle of the application of high-power lasers for the neutralization of explosive devices is based on thermal effects. Heating of the IEDs main charge may occur either by direct irradiation of the explosive material or by heat transfer through the main charge's confinement. The aim of the application of the laser is to achieve a low order burning reaction of the explosive charge and thus a controlled neutralization of the IED. Since laser beams allow for the directed transport of energy, this technique can be applied over long stand-off distances and has thus potential for an increase of the safety of clearing forces and population in the case of terroristic attacks in a civilian environment. Within the ENCOUNTER project, a laboratory environment has been set up which allows for the irradiation of IEDs with a laser power of up to 10 kW. Experiments have been carried out on a broad spectrum of different types of IEDs. The processes during neutralization were studied in detail with high-speed diagnostics. On the basis of these experimental data, the safety and the reliability of the application of the laser was analyzed, and recommendations to end users were given. In addition to the results of the ENCOUNTER project, approaches for the numerical simulation of the neutralization of IEDs are discussed.

  19. Performance evaluation of diaminoazoxyfurazan (DAAF) as a booster material for insensitive high explosives using the onionskin test

    SciTech Connect

    Morris, John S; Francois, Elizabeth G; Hooks, Daniel E; Hill, Larry G; Harry, Herbert H

    2010-11-09

    Initiation of insensitive high explosive (IHE) formulations requires the use of a booster explosive in the initiation train. Booster material selection is crucial, as the initiation must reliably function across some spectrum of physical parameters. The interest in DAAF for this application stems from the fact that it possesses many traits of an IHE but is shock sensitive enough to serve as an explosive booster. A hemispherical wave breakout test, termed the onionskin test, is one of the methods used to evaluate the performance of a booster material. The wave breakout time-position history at the surface of a hemisphericallHE charge is recorded and the relative uniformity of the breakout can be quantitatively compared between booster materials. A series of onionskin tests were performed to investigate breakout and propagation diaminoazoxyfurazan (DAAF) at low temperatures to evaluate ignition and detonation spreading in comparison to other explosives commonly used in booster applications. Some wave perturbation was observed with the DAAF booster in the onionskin tests presented. The results of these tests will be presented and discussed.

  20. Highly sensitive gas-phase explosive detection by luminescent microporous polymer networks

    PubMed Central

    Räupke, André; Palma-Cando, Alex; Shkura, Eugen; Teckhausen, Peter; Polywka, Andreas; Görrn, Patrick; Scherf, Ullrich; Riedl, Thomas

    2016-01-01

    We propose microporous networks (MPNs) of a light emitting spiro-carbazole based polymer (PSpCz) as luminescent sensor for nitro-aromatic compounds. The MPNs used in this study can be easily synthesized on arbitrarily sized/shaped substrates by simple and low-cost electrochemical deposition. The resulting MPN afford an extremely high specific surface area of 1300 m2/g, more than three orders of magnitude higher than that of the thin films of the respective monomer. We demonstrate, that the luminescence of PSpCz is selectively quenched by nitro-aromatic analytes, e.g. nitrobenzene, 2,4-DNT and TNT. In striking contrast to a control sample based on non-porous spiro-carbazole, which does not show any luminescence quenching upon exposure to TNT at levels of 3 ppm and below, the microporous PSpCz shows a clearly detectable response even at TNT concentrations as low as 5 ppb, clearly demonstrating the advantage of microporous films as luminescent sensors for traces of explosive analytes. This level states the vapor pressure of TNT at room temperature. PMID:27373905

  1. Computational Study of 3-D Hot-Spot Initiation in Shocked Insensitive High-Explosive

    NASA Astrophysics Data System (ADS)

    Najjar, F. M.; Howard, W. M.; Fried, L. E.

    2011-06-01

    High explosive shock sensitivity is controlled by a combination of mechanical response, thermal properties, and chemical properties. The interplay of these physical phenomena in realistic condensed energetic materials is currently lacking. A multiscale computational framework is developed investigating hot spot (void) ignition in a single crystal of an insensitive HE, TATB. Atomistic MD simulations are performed to provide the key chemical reactions and these reaction rates are used in 3-D multiphysics simulations. The multiphysics code, ALE3D, is linked to the chemistry software, Cheetah, and a three-way coupled approach is pursued including hydrodynamics, thermal and chemical analyses. A single spherical air bubble is embedded in the insensitive HE and its collapse due to shock initiation is evolved numerically in time; while the ignition processes due chemical reactions are studied. Our current predictions showcase several interesting features regarding hot spot dynamics including the formation of a ``secondary'' jet. Results obtained with hydro-thermo-chemical processes leading to ignition growth will be discussed for various pore sizes and different shock pressures. LLNL-ABS-471438. This work performed under the auspices of the U.S. Department of Energy by LLNL under Contract DE-AC52-07NA27344.

  2. Sensitivity effects of void density and arrangements in a REBO high explosive

    SciTech Connect

    Herring, Stuart Davis; Germann, Timothy C; Gronbech - Jensen, Niels

    2010-09-28

    The shock response of two-dimensional model, high explosive crystals with various arrangements of circular voids is explored. We simulate a piston impact using molecular dynamics simulations with a Reactive Empirical Bond Order (REBO) model potential for a sub-micron, sub-ns exothermic reaction in a diatomic molecular solid. In square lattices of voids all of one size, reducing that size or increasing the porosity while holding the other parameter fixed causes the hotspots to consume the material more quickly and detonation to occur sooner and at lower piston velocities. The early time behavior is seen to follow a very simple ignition and growth model. The hotspots are seen to collectively develop a broad pressure wave (a sonic, diffuse deflagration front) that, upon merging with the lead shock, transforms it into a detonation. The reaction yields produced by triangular lattices are not significantly different. With random void arrangements, the mean time to detonation is 15.5% larger than with the square lattice; the standard deviation of detonation delays is just 5.1%.

  3. Theoretical analysis of the terahertz spectrum of the high explosive PETN.

    PubMed

    Allis, Damian G; Korter, Timothy M

    2006-11-13

    The experimental solid-state terahertz (THz) spectrum (3 to 120 cm(-1)) of the high explosive pentaerythritol tetranitrate (PETN, C(5)H(6)N(4)O(12)) has been modeled using solid-state density functional theory (DFT) calculations. Solid-state DFT, employing the BP density functional, is in best qualitative agreement with the features in the previously reported THz spectrum. The crystal environment of PETN includes numerous intermolecular hydrogen-bonding interactions that contribute to large (up to 80 cm(-1)) calculated shifts in molecular normal-mode positions in the solid state. Comparison of the isolated-molecule and solid-state normal-mode calculations for a series of density functionals reveals the extent to which the inclusion of crystal-packing interactions and the relative motions between molecules are required for correctly reproducing the vibrational structure of solid-state THz spectra. The THz structure below 120 cm(-1) is a combination of both intermolecular (relative rotations and translations) and intramolecular (torsions, large amplitude motions) vibrational motions. Vibrational-mode analyses indicate that the first major feature (67.2 cm(-1)) in the PETN THz spectrum contains all of the optical rotational and translational cell modes and no internal (molecular) vibrational modes.

  4. Characterization of detonation soot produced during steady and overdriven conditions for three high explosive formulations

    NASA Astrophysics Data System (ADS)

    Podlesak, David W.; Huber, Rachel C.; Amato, Ronald S.; Dattelbaum, Dana M.; Firestone, Millicent A.; Gustavsen, Richard L.; Johnson, Carl E.; Mang, Joseph T.; Ringstrand, Bryan S.

    2017-01-01

    The detonation of high explosives (HE) produces a dense fluid of molecular gases and solid carbon. The solid detonation carbon contains various carbon allotropes such as detonation nanodiamonds, onion-like carbon, graphite and amorphous carbon, with the formation of the different forms dependent upon pressure, temperature and the environmental conditions of the detonation. We have collected solid carbon residues from controlled detonations of three HE formulations (Composition B-3, PBX 9501, and PBX 9502). Soot was collected from experiments designed to produce both steady and overdriven conditions, and from detonations in both an ambient (air) atmosphere and in an inert Ar atmosphere. Differences in solid carbon residues were quantified using X-ray photoelectron spectroscopy and carbon isotope measurements. Environmental conditions, HE formulation, and peak pressures influenced the amount of and isotopic composition of the carbon in the soot. Detonations in an Ar atmosphere produced greater amounts of carbon soot with lower δ13C values than those in ambient air. Therefore, solid carbon residues continued to evolve after detonation due to excess oxygen in the ambient air detonations. As well, higher peak pressures in overdriven conditions produced less carbon soot with, in general, higher δ13C values. Consequently, while overdriven conditions only produced peak pressures for a limited duration, it was enough to influence the composition of the solid carbon residues.

  5. Ecological surveys of the proposed high explosives wastewater treatment facility region

    SciTech Connect

    Haarmann, T.

    1995-07-01

    Los Alamos National Laboratory (LANL) proposes to improve its treatment of wastewater from high explosives (HE) research and development activities. The proposed project would focus on a concerted waste minimization effort to greatly reduce the amount of wastewater needing treatment. The result would be a 99% decrease in the HE wastewater volume, from the current level of 6,760,000 L/mo (1,786,000 gal./mo) to 41,200 L/mo (11,000 gal./mo). This reduction would entail closure of HE wastewater outfalls, affecting some wetland areas that depend on HE wastewater effluents. The outfalls also provide drinking water for many wildlife species. Terminating the flow of effluents at outfalls would represent an improvement in water quality in the LANL region but locally could have a negative effect on some wetlands and wildlife species. None of the affected species are protected by any state or federal endangered species laws. The purpose of this report is to briefly discuss the different biological studies that have been done in the region of the project area. This report is written to give biological information and baseline data and the biota of the project area.

  6. New, high-efficiency ion trap mobility detection system for narcotics and explosives

    NASA Astrophysics Data System (ADS)

    McGann, William J.; Bradley, V.; Borsody, A.; Lepine, S.

    1994-10-01

    A new patented Ion Trap Mobility Spectrometer (ITMS) design is presented. Conventional IMS designs typically operate below 0.1% efficiency. This is due primarily to electric field driven, sample ion discharge on a shutter grid. Since 99.9% of the sample ions generated in the reaction region are lost in this discharge process, the sensitivity of conventional systems is limited. The new design provides greater detection efficiency than conventional designs through the use of an `ion trap' concept. The paper describes the plasma and sample ion dynamics in the reaction region of the new detector and discusses the advantages of utilizing a `field-free' space to generate sample ions with high efficiency. Fast electronic switching is described which is used to perturb the field-free space and pulse the sample ions into the drift region for separation and subsequent detection using pseudo real-time software for analysis and display of the data. Many applications for this new detector are now being considered including the detection of narcotics and explosives. Preliminary ion spectra, reduced mobility data and sensitivity data are presented for fifteen narcotics, including cocaine, THC and LSD are reported.

  7. Highly sensitive gas-phase explosive detection by luminescent microporous polymer networks

    NASA Astrophysics Data System (ADS)

    Räupke, André; Palma-Cando, Alex; Shkura, Eugen; Teckhausen, Peter; Polywka, Andreas; Görrn, Patrick; Scherf, Ullrich; Riedl, Thomas

    2016-07-01

    We propose microporous networks (MPNs) of a light emitting spiro-carbazole based polymer (PSpCz) as luminescent sensor for nitro-aromatic compounds. The MPNs used in this study can be easily synthesized on arbitrarily sized/shaped substrates by simple and low-cost electrochemical deposition. The resulting MPN afford an extremely high specific surface area of 1300 m2/g, more than three orders of magnitude higher than that of the thin films of the respective monomer. We demonstrate, that the luminescence of PSpCz is selectively quenched by nitro-aromatic analytes, e.g. nitrobenzene, 2,4-DNT and TNT. In striking contrast to a control sample based on non-porous spiro-carbazole, which does not show any luminescence quenching upon exposure to TNT at levels of 3 ppm and below, the microporous PSpCz shows a clearly detectable response even at TNT concentrations as low as 5 ppb, clearly demonstrating the advantage of microporous films as luminescent sensors for traces of explosive analytes. This level states the vapor pressure of TNT at room temperature.

  8. Low amplitude insult project: PBX 9501 high explosive violent reaction experiments

    SciTech Connect

    Idar, D.J.; Lucht, R.A.; Straight, J.W.; Scammon, R.J.; Browning, R.V.; Middleditch, J.; Dienes, J.K.; Skidmore, C.B.; Buntain, G.A.

    1998-12-31

    The Modified Steven test geometry has been used with several different target designs to investigate the mechanical loading behavior of PBX 9501 to a low velocity impact. A 2 kg. mild steel spigot projectile is launched via a new powder driven gun design, from {approximately} 20 to 105 m/s, at lightly confined, steel targets. Brief descriptions of the gun design and operation are given. The threshold velocity to reaction for various target designs, different PBX 9501 lots, and different high explosive (HE) thicknesses are reported and compared. Various diagnostics have been employed to evaluate the pressure profile and timing, and target strain behavior relative to projectile impact. The violence of reaction, as measured by both passive and active techniques, is reported relative to a steady state detonation in PBX 9501. Experimental results suggest slightly different ignition mechanisms dominate based on (HE) thickness, resulting in delayed reactions from {approximately} 0.2- to 2.8-ms after impact. Post-test analyses of the PBX 9501 are briefly summarized.

  9. High-resolution method applied to premixing phase of steam explosion

    SciTech Connect

    Leskovar, M.; Mavko, B.; Marn, J.

    1997-12-01

    This paper describes the improved version of the general two-dimensional, multiphase flow code ESE. The ESE code has been developed to model the mixing process and interaction of molten core debris with water. In case of a steam explosion, a trigger may produce locally enhanced heat transfer and pressurization and may evolve into a shock propagating through the coarse mixture. The propagation phase of the interaction is not modeled by the code; however, the ESE provides for initial condition evolution in time. The indication of the amount of well-mixed melt at the time of the trigger occurrence can be deduced based on the code`s results. The objective of this work is to present the advantages of the high-resolution method applied to a particular set of partial differential equations and to incorporate these advantages into a code that was conceived using less traveled paths, namely, ensemble averaging and use of available data in probabilistic density functions describing momentum and energy cofluctuation tensors.

  10. Solid-state modeling of the terahertz spectrum of the high explosive HMX.

    PubMed

    Allis, Damian G; Prokhorova, Darya A; Korter, Timothy M

    2006-02-09

    The experimental solid-state terahertz (THz) spectrum (3-120 cm(-1)) of the beta-crystal form of the high explosive octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) has been analyzed using solid-state density functional theory calculations. Various density functionals (both generalized gradient approximation and local density approximation) are compared in terms of their abilities to reproduce the experimentally observed solid-state structure and low-frequency vibrational motions. Good-to-excellent agreement between solid-state theory and experiment can be achieved in the THz region where isolated-molecule calculations fail to reproduce the observed spectral features, demonstrating a clear limitation of using isolated-molecule calculations for the assignment of THz frequency motions in molecular solids. The deficiency of isolated-molecule calculations is traced to modification of the molecular structure in the solid state through crystal packing effects and the formation of weak C-H...O hydrogen bonds.

  11. Tailoring wet explosion process parameters for the pretreatment of cocksfoot grass for high sugar yields.

    PubMed

    Njoku, S I; Ahring, B K; Uellendahl, H

    2013-08-01

    The pretreatment of lignocellulosic biomass is crucial for efficient subsequent enzymatic hydrolysis and ethanol fermentation. In this study, wet explosion (WEx) pretreatment was applied to cocksfoot grass and pretreatment conditions were tailored for maximizing the sugar yields using response surface methodology. The WEx process parameters studied were temperature (160-210 °C), retention time (5-20 min), and dilute sulfuric acid concentration (0.2-0.5 %). The pretreatment parameter set E, applying 210 °C for 5 min and 0.5 % dilute sulfuric acid, was found most suitable for achieving a high glucose release with low formation of by-products. Under these conditions, the cellulose and hemicellulose sugar recovery was 94 % and 70 %, respectively. The efficiency of the enzymatic hydrolysis of cellulose under these conditions was 91 %. On the other hand, the release of pentose sugars was higher when applying less severe pretreatment conditions C (160 °C, 5 min, 0.2 % dilute sulfuric acid). Therefore, the choice of the most suitable pretreatment conditions is depending on the main target product, i.e., hexose or pentose sugars.

  12. Damage & fracture of high-explosive mock subject to cyclic loading

    SciTech Connect

    Liu, Cheng; Rae, Philip J; Cady, Carl M; Lovato, Manuel L

    2011-01-11

    We use four-point bend specimen with a single shallow edge notch to study the fracture process in Mock 900-21, a PBX 9501 high explosive simulant mock. Subject to monotonic loading we determine quantitatively the threshold load for macroscopic crack initiation from the notch tip. The four-point bend specimen is then subject to cyclic loading in such a way that during the first cycle, the applied force approaches but does not exceed the threshold load determined from the monotonic loading test and in the subsequent cycles, the overall maximum deformation is maintained to be equal to that of the first cycle. It is expected and is also confirmed that no macroscopic damage and cracking occur during the first cycle. However, we observe that sizable macroscopic crack is generated and enlarged during the subsequent cycles, even though the applied force never exceeds the threshold load. Details of the process of damage fonnation, accumulation, and crack extension are presented and the mechanical mechanism responsible for such failure process is postulated and discussed.

  13. Characterization of Detonation Soot Produced During Steady and Overdriven Conditions for Three High Explosive Formulations

    NASA Astrophysics Data System (ADS)

    Podlesak, David; Amato, Ronald; Dattelbaum, Dana; Firestone, Millicent; Gustavsen, Richard; Huber, Rachel; Ringstrand, Bryan

    2015-06-01

    The detonation of high explosives (HE) produces a dense fluid of molecular gases and solid carbon. The solid detonation carbon contains various carbon allotropes such as detonation nanodiamonds, ``onion-like'' carbon, graphite and amorphous carbon, with the formation of the different forms dependent upon pressure, temperature and the environmental conditions of the detonation. We have collected solid carbon residues from controlled detonations of three HE formulations (Composition B-3, PBX 9501, and PBX 9502). Soot was collected from experiments designed to produce both steady and overdriven conditions, and from detonations in both an ambient (air) atmosphere and in an inert Ar atmosphere. Structural studies to glean the features of the solid carbon products have been performed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), Raman spectroscopy, small-angle X-ray scattering (SAXS), and X-Ray Pair Distribution Function measurements (PDF). Bulk soot was also analyzed for elemental and isotopic compositions. We will discuss differences in the structure and composition of the detonation carbon as a function of formulation, detonation conditions, and the surrounding atmosphere.

  14. Critical velocities for deflagration and detonation triggered by voids in a REBO high explosive

    SciTech Connect

    Herring, Stuart Davis; Germann, Timothy C; Jensen, Niels G

    2010-01-01

    The effects of circular voids on the shock sensitivity of a two-dimensional model high explosive crystal are considered. We simulate a piston impact using molecular dynamics simulations with a Reactive Empirical Bond Order (REBO) model potential for a sub-micron, sub-ns exothermic reaction in a diatomic molecular solid. The probability of initiating chemical reactions is found to rise more suddenly with increasing piston velocity for larger voids that collapse more deterministically. A void with radius as small as 10 nm reduces the minimum initiating velocity by a factor of 4. The transition at larger velocities to detonation is studied in a micron-long sample with a single void (and its periodic images). The reaction yield during the shock traversal increases rapidly with velocity, then becomes a prompt, reliable detonation. A void of radius 2.5 nm reduces the critical velocity by 10% from the perfect crystal. A Pop plot of the time-to-detonation at higher velocities shows a characteristic pressure dependence.

  15. An X-band high-impedance relativistic klystron amplifier with an annular explosive cathode

    SciTech Connect

    Zhu, Danni; Zhang, Jun Zhong, Huihuang; Qi, Zumin

    2015-11-15

    The feasibility of employing an annular beam instead of a solid one in the X-band high-impedance relativistic klystron amplifier (RKA) is investigated in theory and simulation. Small-signal theory analysis indicates that the optimum bunching distance, fundamental current modulation depth, beam-coupling coefficient, and beam-loaded quality factor of annular beams are all larger than the corresponding parameters of solid beams at the same beam voltage and current. An annular beam RKA and a solid beam RKA with almost the same geometric parameters are compared in particle-in-cell simulation. Output microwave power of 100 MW, gain of 50 dB, and power conversion efficiency of 42% are obtained in an annular beam RKA. The annular beam needs a 15% lower uniform guiding magnetic field than the solid beam. Our investigations demonstrate that we are able to use a simple annular explosive cathode immersed in a lower uniform magnetic field instead of a solid thermionic cathode in a complicated partially shielding magnetic field for designing high-impedance RKA, which avoids high temperature requirement, complicated electron-optical system, large area convergence, high current density, and emission uniformity for the solid beam. An equivalent method for the annular beam and the solid beam on bunching features is proposed and agrees with the simulation. The annular beam has the primary advantages over the solid beam that it can employ the immersing uniform magnetic field avoiding the complicated shielding magnetic field system and needs a lower optimum guiding field due to the smaller space charge effect.

  16. An X-band high-impedance relativistic klystron amplifier with an annular explosive cathode

    NASA Astrophysics Data System (ADS)

    Zhu, Danni; Zhang, Jun; Zhong, Huihuang; Qi, Zumin

    2015-11-01

    The feasibility of employing an annular beam instead of a solid one in the X-band high-impedance relativistic klystron amplifier (RKA) is investigated in theory and simulation. Small-signal theory analysis indicates that the optimum bunching distance, fundamental current modulation depth, beam-coupling coefficient, and beam-loaded quality factor of annular beams are all larger than the corresponding parameters of solid beams at the same beam voltage and current. An annular beam RKA and a solid beam RKA with almost the same geometric parameters are compared in particle-in-cell simulation. Output microwave power of 100 MW, gain of 50 dB, and power conversion efficiency of 42% are obtained in an annular beam RKA. The annular beam needs a 15% lower uniform guiding magnetic field than the solid beam. Our investigations demonstrate that we are able to use a simple annular explosive cathode immersed in a lower uniform magnetic field instead of a solid thermionic cathode in a complicated partially shielding magnetic field for designing high-impedance RKA, which avoids high temperature requirement, complicated electron-optical system, large area convergence, high current density, and emission uniformity for the solid beam. An equivalent method for the annular beam and the solid beam on bunching features is proposed and agrees with the simulation. The annular beam has the primary advantages over the solid beam that it can employ the immersing uniform magnetic field avoiding the complicated shielding magnetic field system and needs a lower optimum guiding field due to the smaller space charge effect.

  17. Particle size analysis of prepared solutions and fingerprint deposits of high explosive materials

    SciTech Connect

    Carmack, W.J.; Hembree, P.B.

    1998-03-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) managed and operated by Lockheed Martin Idaho Technologies Company (LMITCO) was tasked via the Federal Aviation Administration (FAA) and US Department of Energy (DOE) to conduct various studies involving the detection and measurement of explosive materials and their associated residues. This report details the results of an investigation to determine the particle size characteristics of the explosive materials used in the design, development, and testing of trace explosives detection systems. These materials, in the form of water suspensions of plastic explosives, are used to provide a quantitative means of monitoring the performance characteristics of the detection systems. The purpose of this investigation is to provide data that allows a comparison between the particles deposited using the suspension standards and the particles deposited from fingerprints. This information may support the development of quality control aids, measurement methods, or performance criteria specifications for the use of trace explosives detection systems. For this report, particle size analyses were completed on explosives standard suspensions/solutions for composition C-4, Semtex-H, and Detasheet and fingerprints for C-4, Detasheet, and pentolite. Because of the difficulty in collecting microscopic images of the particles in the suspensions from test protocol surfaces, this paper discusses the characteristics of the particles as they are found on metal, glass, and paper. The results of the particle characterization analyses indicate that the water suspensions contain particulate composed of binder materials and dissolved portions of the explosive compounds. Upon drying of the water suspensions, significant particle nucleation and growth is observed. The nucleated particulate is comparable to the particulate deposited by fingerprints.

  18. Explosively pumped laser light

    DOEpatents

    Piltch, Martin S.; Michelotti, Roy A.

    1991-01-01

    A single shot laser pumped by detonation of an explosive in a shell casing. The shock wave from detonation of the explosive causes a rare gas to luminesce. The high intensity light from the gas enters a lasing medium, which thereafter outputs a pulse of laser light to disable optical sensors and personnel.

  19. THE HIGH-METALLICITY EXPLOSION ENVIRONMENT OF THE RELATIVISTIC SUPERNOVA 2009bb

    SciTech Connect

    Levesque, E. M.; Kewley, L. J.; Soderberg, A. M.; Foley, R. J.; Berger, E.; Torres, M. A. P.; Challis, P.; Kirshner, R. P.; Copete, A.; Chakraborti, S.; Ray, A.; Barthelmy, S. D.; Bietenholz, M. F.; Chandra, P.; Chaplin, V.; Connaughton, V.; Chevalier, R. A.; Fox, O.; Chugai, N.; Fransson, C.

    2010-01-20

    We investigate the environment of the nearby (d {approx} 40 Mpc) broad-lined Type Ic supernova (SN) 2009bb. This event was observed to produce a relativistic outflow likely powered by a central accreting compact object. While such a phenomenon was previously observed only in long-duration gamma-ray bursts (LGRBs), no LGRB was detected in association with SN 2009bb. Using an optical spectrum of the SN 2009bb explosion site, we determine a variety of interstellar medium properties for the host environment, including metallicity, young stellar population age, and star formation rate. We compare the SN explosion site properties to observations of LGRB and broad-lined SN Ic host environments on optical emission line ratio diagnostic diagrams. Based on these analyses, we find that the SN 2009bb explosion site has a metallicity between 1.7 Z {sub sun} and 3.5 Z {sub sun}, in agreement with other broad-lined SN Ic host environments and at odds with the low-redshift LGRB host environments and recently proposed maximum metallicity limits for relativistic explosions. We consider the implications of these findings and the impact that SN 2009bb's unusual explosive properties and environment have on our understanding of the key physical ingredient that enables some SNe to produce a relativistic outflow.

  20. Development of an air cleaning system for dissolving high explosives from nuclear warheads

    SciTech Connect

    Bergman, W.; Wilson, K.; Staggs, K.; Wapman, D.

    1997-08-01

    The Department of Energy (DOE) has a major effort underway in dismantling nuclear weapons. In support of this effort we have been developing a workstation for removing the high explosive (HE) from nuclear warheads using hot sprays of dimethyl sulfoxide (DMSO) solvent to dissolve the HE. An important component of the workstation is the air cleaning system that is used to contain DMSO aerosols and vapor and radioactive aerosols. The air cleaning system consists of a condenser to liquefy the hot DMSO vapor, a demister pad to remove most of the DMSO aerosols, a high efficiency particulate air (HEPA) filter to remove the remaining aerosols, an activated carbon filter to remove the DMSO vapor, and a final HEPA filter to meet the redundancy requirement for HEPA filters in radioactive applications. The demister pad is a 4{double_prime} thick mat of glass and steel fibers and was selected after conducting screening tests on promising candidates. We also conducted screening tests on various activated carbons and found that all had a similar performance. The carbon breakthrough curves were fitted to a modified Wheeler`s equation and gave excellent predictions for the effect of different flow rates. After all of the components were assembled, we ran a series of performance tests on the components and system to determine the particle capture efficiency as a function of size for dioctyl sebacate (DOS) and DMSO aerosols using laser particle counters and filter samples. The pad had an efficiency greater than 990% for 0.1 {mu}m DMSO particles. Test results on the prototype carbon filter showed only 70% efficiency, instead of the 99.9% in small scale laboratory tests. Thus further work will be required to develop the prototype carbon filter. 7 refs., 18 figs., 10 tabs.

  1. Potassium 1,1'-dinitramino-5,5'-bistetrazolate: a primary explosive with fast detonation and high initiation power.

    PubMed

    Fischer, Dennis; Klapötke, Thomas M; Stierstorfer, Jörg

    2014-07-28

    Adequate primary explosives such as lead azide mostly contain toxic ingredients, which have to be replaced. A new candidate that shows high potential, potassium 1,1'-dinitramino-5,5'-bistetrazolate (K2DNABT), was synthesized by a sophisticated synthetic procedure based on dimethylcarbonate and glyoxal. It was intensively characterized for its chemical (X-ray diffraction, EA, NMR and vibrational spectroscopy) and physico-chemical properties (sensitivity towards impact, friction, and electrostatic, DSC). The obtained primary explosive combines good thermal stability with the desired mechanical stability. Owing to its high heat of formation (326 kJ mol(-1)) and density (2.11 g cm(-3)), impressive values for its detonation velocity (8330 m s(-1)) and pressure (311 kbar) were computed. Its superior calculated performance output was successfully confirmed and demonstrated by different convenient energetic test methods.

  2. Numerical simulation of Composition B high explosive charge desensitization in gap test assembly after loading by precursor wave

    NASA Astrophysics Data System (ADS)

    Balagansky, I. A.; Stepanov, A. A.

    2016-03-01

    Results of numerical research into the desensitization of high explosive charges in water gap test-based experimental assemblies are presented. The experimental data are discussed, and the analysis using ANSYS AUTODYN 14.5 is provided. The desensitization phenomenon is well reproduced in numerical simulation using the JWL EOS and the Lee-Tarver kinetic equation for modeling of the initiation of heterogeneous high explosives with as well as without shock front waves. The analysis of the wave processes occurring during the initiation of the acceptor HE charge has been carried out. Peculiarities of the wave processes in the water gap test assemblies, which can influence the results of sensitivity measurement, have been studied. In particular, it has been established that precursor waves in the walls of the gap test assemblies can influence the detonation transmission distance.

  3. The Off-Site Plowshare and Vela Uniform Programs: Assessing Potential Environmental Liabilities through an Examination of Proposed Nuclear Projects,High Explosive Experiments, and High Explosive Construction Activities Volume 2 of 3

    SciTech Connect

    Beck Colleen M.,Edwards Susan R.,King Maureen L.

    2011-09-01

    This document presents the results of nearly six years (2002-2008) of historical research and field studies concerned with evaluating potential environmental liabilities associated with U.S. Atomic Energy Commission projects from the Plowshare and Vela Uniform Programs. The Plowshare Program's primary purpose was to develop peaceful uses for nuclear explosives. The Vela Uniform Program focused on improving the capability of detecting, monitoring and identifying underground nuclear detonations. As a result of the Project Chariot site restoration efforts in the early 1990s, there were concerns that there might be other project locations with potential environmental liabilities. The Desert Research Institute conducted archival research to identify projects, an analysis of project field activities, and completed field studies at locations where substantial fieldwork had been undertaken for the projects. Although the Plowshare and Vela Uniform nuclear projects are well known, the projects that are included in this research are relatively unknown. They are proposed nuclear projects that were not executed, proposed and executed high explosive experiments, and proposed and executed high explosive construction activities off the Nevada Test Site. The research identified 170 Plowshare and Vela Uniform off-site projects and many of these had little or no field activity associated with them. However, there were 27 projects that merited further investigation and field studies were conducted at 15 locations.

  4. The Off-Site Plowshare and Vela Uniform Programs: Assessing Potential Environmental Liabilities through an Examination of Proposed Nuclear Projects,High Explosive Experiments, and High Explosive Construction Activities Volume 3 of 3

    SciTech Connect

    Beck Colleen M.,Edwards Susan R.,King Maureen L.

    2011-09-01

    This document presents the results of nearly six years (2002-2008) of historical research and field studies concerned with evaluating potential environmental liabilities associated with U.S. Atomic Energy Commission projects from the Plowshare and Vela Uniform Programs. The Plowshare Program's primary purpose was to develop peaceful uses for nuclear explosives. The Vela Uniform Program focused on improving the capability of detecting, monitoring and identifying underground nuclear detonations. As a result of the Project Chariot site restoration efforts in the early 1990s, there were concerns that there might be other project locations with potential environmental liabilities. The Desert Research Institute conducted archival research to identify projects, an analysis of project field activities, and completed field studies at locations where substantial fieldwork had been undertaken for the projects. Although the Plowshare and Vela Uniform nuclear projects are well known, the projects that are included in this research are relatively unknown. They are proposed nuclear projects that were not executed, proposed and executed high explosive experiments, and proposed and executed high explosive construction activities off the Nevada Test Site. The research identified 170 Plowshare and Vela Uniform off-site projects and many of these had little or no field activity associated with them. However, there were 27 projects that merited further investigation and field studies were conducted at 15 locations.

  5. The Off-Site Plowshare and Vela Uniform Programs: Assessing Potential Environmental Liabilities through an Examination of Proposed Nuclear Projects,High Explosive Experiments, and High Explosive Construction Activities Volume 1 of 3

    SciTech Connect

    Beck Colleen M,Edwards Susan R.,King Maureen L.

    2011-09-01

    This document presents the results of nearly six years (2002-2008) of historical research and field studies concerned with evaluating potential environmental liabilities associated with U.S. Atomic Energy Commission projects from the Plowshare and Vela Uniform Programs. The Plowshare Program's primary purpose was to develop peaceful uses for nuclear explosives. The Vela Uniform Program focused on improving the capability of detecting, monitoring and identifying underground nuclear detonations. As a result of the Project Chariot site restoration efforts in the early 1990s, there were concerns that there might be other project locations with potential environmental liabilities. The Desert Research Institute conducted archival research to identify projects, an analysis of project field activities, and completed field studies at locations where substantial fieldwork had been undertaken for the projects. Although the Plowshare and Vela Uniform nuclear projects are well known, the projects that are included in this research are relatively unknown. They are proposed nuclear projects that were not executed, proposed and executed high explosive experiments, and proposed and executed high explosive construction activities off the Nevada Test Site. The research identified 170 Plowshare and Vela Uniform off-site projects and many of these had little or no field activity associated with them. However, there were 27 projects that merited further investigation and field studies were conducted at 15 locations.

  6. Hand held explosives detection system

    DOEpatents

    Conrad, Frank J.

    1992-01-01

    The present invention is directed to a sensitive hand-held explosives detection device capable of detecting the presence of extremely low quantities of high explosives molecules, and which is applicable to sampling vapors from personnel, baggage, cargo, etc., as part of an explosives detection system.

  7. Reliable discrimination of high explosive and chemical/biological artillery using acoustic UGS

    NASA Astrophysics Data System (ADS)

    Hohil, Myron E.; Desai, Sachi

    2005-10-01

    discrimination between conventional and simulated chemical/biological artillery rounds using acoustic signals produced during detonation. Distinct characteristics arise within the different airburst signatures because high explosive warheads emphasize concussive and shrapnel effects, while chemical/biological warheads are designed to disperse their contents over large areas, therefore employing a slower burning, less intense explosive to mix and spread their contents. The ensuing blast waves are readily characterized by variations in the corresponding peak pressure and rise time of the blast, differences in the ratio of positive pressure amplitude to the negative amplitude, and variations in the overall duration of the resulting waveform. We show that, highly reliable discrimination (> 98%) between conventional and potentially chemical/biological artillery is achieved at ranges exceeding 3km. A feedforward neural network classifier, trained on a feature space derived from the distribution of wavelet coefficients found within different levels of the multiresolution decomposition yields.

  8. New Mix Explosives for Explosive Welding

    NASA Astrophysics Data System (ADS)

    Andreevskikh, Leonid

    2011-06-01

    Suggested and tested were some mix explosives--powder mixtures of a brisant high explosive (HE = RDX, PETN) and an inert diluent (baking soda)--for use in explosive welding. RDX and PETN were selected in view of their high throwing ability and low critical diameter. Since the decomposition of baking soda yields a huge amount of gaseous products, its presence ensures (even at a low HE percentage) a throwing speed that is sufficient for realization of explosive welding, at a reduced brisant action of charge. Mix chargers containing 30-70 wt % HE (the rest baking soda) have been tested experimentally and optimized. For study of possibility to reduce critical diameter of HE mixture, the mixture was prepared where HE crystal sizes did not exceed 10 μm. The tests, which were performed with this HE, revealed that the mixture detonated stably with the velocity D ~ 2 km/s, if the layer thickness was d = 2 mm. The above explosives afford to markedly diminish deformations within the oblique impact zone and thus to carry out explosive welding of hollow items and thin metallic foils.

  9. Chemical and biological systems for regenerating activated carbon contaminated with high explosives

    SciTech Connect

    Knezovich, J.P.; Daniels, J.I.; Stenstrom, M.K.; Heilmann, H.M.

    1994-12-01

    Activated carbon has been used as a substrate for efficiently removing high explosives (HEs) from aqueous and gaseous waste streams. Carbon that is saturated with HEs, however, constitutes a solid waste and is currently being stored because appropriate technologies for its treatment are not available. Because conventional treatment strategies (i.e., incineration, open burning) are not safe or will not be in compliance with future regulations, new and cost-effective methods are required for the elimination of this solid waste. Furthermore, because the purchase of activated carbon and its disposal after loading with HEs will be expensive, an ideal treatment method would result in the regeneration of the carbon thereby permitting its reuse. Coupling chemical and biological treatment systems, such as those described below, will effectively meet these technical requirements. The successful completion of this project will result in the creation of engineered commercial systems that will present safe and efficient methods for reducing the quantities of HE-laden activated carbon wastes that are currently in storage or are generated as a result of demilitarization activities. Biological treatment of hazardous wastes is desirable because the biodegradation process ultimately leads to the mineralization (e.g., conversion to carbon dioxide, nitrogen gas, and water) of parent compounds and has favorable public acceptance. These methods will also be cost- effective because they will not require large expenditures of energy and will permit the reuse of the activated carbon. Accordingly, this technology will have broad applications in the private sector and will be a prime candidate for technology transfer.

  10. High explosive testing of a corrugated metal blast shelter with membrane blast doors

    SciTech Connect

    Zimmerman, G.P.; Chester, C.V.

    1984-12-01

    In October 1983 the Defense Nuclear Agency (DNA) sponsored a high-explosive blast test, nicknamed DIRECT COURSE. This event simulated the blast effects from a one-kiloton nuclear detonation and provided an environment for the testing of selected blast and fallout shelters for their structural integrity. Under work for the Federal Emergency Management Agency (FEMA), the Oak Ridge National Laboratory (ORNL) fielded a set of experiments at the DIRECT COURSE event which were directed toward reducing the cost of blast shelter for small groups of people, such as workers in critical industries (keyworkers). Six items were tested: three scale models of a corrugated metal blast shelter and three full-size blast door closures for such a shelter. The three shelters survived blast overpressures up to 2.55 MPa (225 psi), a level which is equivalent to being approximately 800 m (0.5 mile) from a 1 megaton nuclear detonation. Each shelter model was 180 cm (6 ft.) long by 60 cm (2 ft.) in diameter, was buried about 60 cm (2 ft.) below ground level, and represented a 1/4-scale version of a full-size blast shelter which would be capable of supporting 12 to 18 occupants. The three full-size, 90 cm (35 in.) diameter, blast doors for such a shelter also successfully resisted the same range of blast overpressure. Each door weighed less than 45 kg (100 lb) and incorporated a novel, yielding-membrane design. These sheet metal membranes were between 1.3 and 2.0 mm (0.050 and 0.080 in.) thick and were supported by an edge beam (hoop).

  11. Chemical and biological systems for treating waste streams contaminated with high explosives

    SciTech Connect

    Knezovich, J.P.; Daniels, J.L.; Stenstrom, M.K.; Heilmann, H.M.

    1995-11-01

    The removal of high explosives (HIE) from ordnance is being accomplished via washout steamout procedures. Because large volumes of waste water are generated by these processes, safe and efficient methods must be developed for their treatment. Activated carbon can be used to efficiently remove HE from aqueous waste streams, but carbon that is laden with HE constitutes a hazardous solid waste. Although conventional treatment methods (i.e., incineration, open burning) are available, they may not be in compliance with existing or future environmental regulations. New and cost-effective methods are therefore required for the elimination of this solid waste. We are developing and demonstrating coupled chemical and biological systems for the safe and economical treatment of HE-laden activated carbon. We have developed a completely engineered treatment system to accomplish this objective and have been operating a pilot treatment system at the Pantex Plant in Amarillo, TX. In this system, HE- contaminated waste water is treated first by activated-carbon adsorption columns. The HE sorbed to carbon is subsequently recovered via heated solvent elution or by base hydrolysis. The HE- or hydrolysate-laden fluid is then treated using a denitrifying culture of microorganisms, which converts the HE or hydrolysate byproducts to less hazardous endproducts. With these methods, the treated carbon can either be re-used or disposed as a nonhazardous waste. This strategy, which has been shown to be effective for the regeneration of carbon and the degradation of RDX and HMX, will be applicable to other energetic chemicals sorbed to activated carbon.

  12. PBX 9501 high explosive violent response/low amplitude insult project: Phase I

    SciTech Connect

    Idar, D.J.; Lucht, R.A.; Scammon, R.; Straight, J.; Skidmore, C.B.

    1997-01-01

    Preliminary modeling and experimental analyses of the violent reaction threshold of semi-heavily confined PBX 9501 to low velocity impact have been completed. Experimental threshold measurements were obtained with ten tests using a spigot gun design to launch a hemispherical projectile at the high explosive contained in stainless steel. Powder curves were determined for several gun barrel designs, powders, and projectile materials and have proven to be very reproducible over the range of 75 to 325 ft/s. A threshold velocity of approximately 246 ft/s for violent reaction of the PBX 9501 was determined with experimental gauge and switch measurements and the remaining physical test evidence. Preliminary analyses of the PBX 9501 samples retrieved from both unreacted and partially reacted targets have been completed. Core samples were obtained from the unreacted targets and submitted for density determinations. The subsequent analysis supports the concept that the PBX 9501 yields and fractures under the low velocity compression event to expand and fill the annular gap in the target design. Samples of PBX 9501 from the partially reacted targets were examined with scanning electron microscope and light microscope techniques. Increased evidence of mechanical twinning effects are noted in the HMX crystals from the partially reacted targets. Finite element calculations using DYNA213, with a modified ORION post processor, without reaction or chemistry models, were used to support the design of targets, to compare predictive analyses with experimental measurements, and to evaluate a proposed ignition criterion in a power law form for threshold to reaction with dependence on pressure, maximum shear strain rate, and time variables. The calculations show good agreement with the physical dent and deformation data from the remaining target evidence; however, they do not match the experimental pressure gauge measurements well.

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

    NASA Astrophysics Data System (ADS)

    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.

  14. Field-based study of volcanic ash via visible and thermal high-speed imaging of explosive eruptions

    NASA Astrophysics Data System (ADS)

    Tournigand, Pierre-Yves; Taddeucci, Jacopo; Scarlato, Piergiorgio; Gaudin, Damien; Del Bello, Elisabetta

    2015-04-01

    Subaerial explosive volcanic activity ejects a mixture of gas-ash-pyroclasts in the atmosphere. Parameterizing the physical processes responsible for ash injection and plume dynamics is crucial to constrain numerical models and forecasts of potentially hazardous ash dispersal events. In this study we present preliminary results from a new method based on visible and thermal high-speed video processing from Strombolian and Vulcanian explosions. High-speed videos were recorded by a Optronis CR600x2 camera (1280x1024 pixels definition, 500 Hz frame rate) for the visible and by a FLIR SC655 (640x480 pixels definition, 50 Hz frame rate) for the thermal. Qualitatively, different dynamics of ash injection and dispersal can be identified. High speed cameras allow us to observe all the different phases during volcanic plume dispersion with a very good time resolution. Multiple features were already observed about volcanic plumes, but this tool give a better accuracy to our observations and allow us to better define previously observed features and to be able to identify new ones. Quantitatively before using our videos a pre-processing is needed which aim is to isolate the plume from the background by using different types of filters without altering the data, to allow us to use automated procedures to track volcanic plumes. In this study we extract data from these videos (plume height, velocity, temperature, mass, volume,...) using different software tools. Doing this allow us to be able to define and constrain main parameters and processes in function of the observed volcano and explosion type, but also to find correlations between parameters and establish empirical relations. We define range of values for each parameter and their respective impact on plume dynamics and stability, to be able to obtain characteristic fields of values for each case and link it to explosions type and evolution.

  15. Combustion and Micro-Explosion of Water/Oil Emulsions in High Pressure Environments.

    DTIC Science & Technology

    1986-03-11

    subtle when this Leidenfrost Phenomenon is coupled to the kinetic process of ignition. Experimentally we nave found that droplet ignition can be...thermal explosion. These results can be satisfactorily explained on the basis of Leidenfrost vaporization, the intensity of diffusive and buoyant mixing

  16. Explosion Driven Magnetogasdynamic Flows with High Magnetic Reynolds and Interaction Numbers.

    DTIC Science & Technology

    1981-12-01

    generator I is analyzed in which the driving electromotoric force is due to electric polarization in the stress field of an explosion produced shock...been pre- sented, in which the electromotoric force is produced by electric polarization I of a solid in the stress field of a shock wave. The

  17. Generation of High-Frequency P and S Wave Radiation from Underground Explosions

    DTIC Science & Technology

    2011-12-30

    tectonic shear stress or anisotropy in the initial fracture distribution. 15. SUBJECT TERMS Shear waves, Seismic sources, Model seismology, P and S wave...of Source Parameters by Amplitude Equalization of Seismic Surface Waves, 2. Release of Tectonic Strain by Underground Explosions and Mechanisms of...12 7. Damage in a Glass Plate Produced by a Hypervelocity Impact

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

    SciTech Connect

    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.

  19. High Explosives Mixtures Detection Using Fiber Optics Coupled: Grazing Angle Probe/Fourier Transform Reflection Absorption Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Primera-Pedrozo, Oliva M.; Soto-Feliciano, Yadira M.; Pacheco-Londoño, Leonardo C.; Hernández-Rivera, Samuel P.

    2008-12-01

    Fourier Transform Infrared Spectroscopy operating in Reflection-Absorption mode has been demonstrated as a potential spectroscopic technique to develop new methodologies for detection of chemicals deposited on metallic surfaces. Mid-IR transmitting optical fiber bundle coupled to an external Grazing Angle Probe and an MCT detector together with a bench Michelson interferometer have been used to develop a highly sensitive and selective methodology for detecting traces of organic compounds on metal surfaces. The methodology is remote sensed, in situ and can detect surface loading concentrations of nanograms/cm2 of most target compounds. It is an environmentally friendly, solvent free technique that does not require sample preparation. In this work, the ever-important task of high explosives detection, present as traces of neat crystalline forms and in lab-made mixtures, equivalent to the important explosive formulation Pentolite, has been addressed. The sample set consisted of TNT, PETN (both pure samples) and the formulation based on them: Pentolite, present in various loading concentrations. The spectral data collected was subjected to a number of statistical pre-treatments, including first derivative and normalization transformations to make the data more suitable for the analysis. Principal Components Analysis combined with Linear Discriminant Analysis allowed the classification and discrimination of the target analytes contained in the sample set. Loading concentrations as 220 ng/cm2 were detected for each explosive in neat form and the in the simulated mixture of Pentolite.

  20. High seas to high explosives: the evolution of calcaneus fracture management in the military.

    PubMed

    Balazs, George C; Polfer, Elizabeth M; Brelin, Alaina M; Gordon, Wade T

    2014-11-01

    Calcaneus fractures typically occur as a consequence of axial load. In the civilian population, this is most often because of motor vehicle accidents or falls from height. Early management of these injuries in the military population largely mirrored that of civilian surgeons. However, calcaneus fractures secondary to underfoot blasts became a significant source of morbidity and mortality in World War II. First described in the aftermath of large-scale naval battles between metal-deck ships, this "deck-slap" phenomenon is associated with high rates of concomitant injuries, infection, and amputation. We review the historical and contemporary management of calcaneus fractures by military orthopedic surgeons, as well as detailing the unique challenges faced in managing the soft-tissue component and associated injuries commonly observed in this population. Combat-related calcaneus fractures are associated with very high rates of concomitant injuries and extensive soft-tissue wounds. Despite significant research and technological advances, functional outcomes following these devastating injuries have remained unsatisfying. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

  1. Cyclic Explosivity in High Elevation Phreatomagmatic Eruptions at Ocean Island Volcanoes: Implications for Aquifer Pressurization and Volcano Flank Destabilization.

    NASA Astrophysics Data System (ADS)

    Tarff, R.; Day, S. J.; Downes, H.; Seghedi, I.

    2015-12-01

    Groundwater heating and pressurization of aquifers trapped between dikes in ocean island volcanoes has been proposed as a mechanism for destabilizing and triggering large-volume flank collapses. Previous modelling has indicated that heat transfer from sustained magma flow through dikes during eruption has the potential to produce destabilizing levels of pressure on time scales of 4 to 400 days, if the aquifers remain confined. Here we revisit this proposal from a different perspective. We examine evidence for pressure variations in dike-confined aquifers during eruptions at high elevation vents on ocean island volcanoes. Initially magmatic, these eruptions change to mostly small-volume explosive phreatomagmatic activity. A recent example is the 1949 eruption on La Palma, Canary Islands. Some such eruptions involve sequences of larger-volume explosive phases or cycles, including production of voluminous low-temperature, pyroclastic density currents (PDC). Here we present and interpret data from the Cova de Paul crater eruption (Santo Antao, Cape Verde Islands). The phreatomagmatic part of this eruption formed two cycles, each culminating with eruption of PDCs. Compositional and textural variations in the products of both cycles indicate that the diatreme fill began as coarse-grained and permeable which allowed gas to escape. During the eruption, the fill evolved to a finer grained, poorly sorted, less permeable material, in which pore fluid pressures built up to produce violent explosive phases. This implies that aquifers adjacent to the feeder intrusion were not simply depressurized at the onset of phreatomagmatic explosivity but experienced fluctuations in pressure throughout the eruption as the vent repeatedly choked and emptied. In combination with fluctuations in magma supply rate, driving of aquifer pressurization by cyclical vent choking will further complicate the prediction of flank destabilization during comparable eruptions on ocean island volcanoes.

  2. Application of Solid Sorbent Collection Techniques and High Performance Liquid Chromatography with Electrochemical Detection to the Analysis of Explosives in Water Samples.

    DTIC Science & Technology

    1986-11-01

    Methods were developed for the determination of several explosives components (nitro-organic compounds) in environmental waters. The methods are based on Porapak resin adsorption and Amberlite XAD-4 resin adsorption of the explosives are measured by high performance liquid chromatography with electrochemical detection. The technique provides a high degree of selectivity and sensitivity for these compounds in actual samples. Detection limits approach 1 microgram/l for many components.

  3. Description and validation of ERAD: An atmospheric dispersion model for high explosive detonations

    SciTech Connect

    Boughton, B.A.; DeLaurentis, J.M.

    1992-10-01

    The Explosive Release Atmospheric Dispersion (ERAD) model is a three-dimensional numerical simulation of turbulent atmospheric transport and diffusion. An integral plume rise technique is used to provide a description of the physical and thermodynamic properties of the cloud of warm gases formed when the explosive detonates. Particle dispersion is treated as a stochastic process which is simulated using a discrete time Lagrangian Monte Carlo method. The stochastic process approach permits a more fundamental treatment of buoyancy effects, calm winds and spatial variations in meteorological conditions. Computational requirements of the three-dimensional simulation are substantially reduced by using a conceptualization in which each Monte Carlo particle represents a small puff that spreads according to a Gaussian law in the horizontal directions. ERAD was evaluated against dosage and deposition measurements obtained during Operation Roller Coaster. The predicted contour areas average within about 50% of the observations. The validation results confirm the model's representation of the physical processes.

  4. Description and validation of ERAD: An atmospheric dispersion model for high explosive detonations

    SciTech Connect

    Boughton, B.A.; DeLaurentis, J.M.

    1992-10-01

    The Explosive Release Atmospheric Dispersion (ERAD) model is a three-dimensional numerical simulation of turbulent atmospheric transport and diffusion. An integral plume rise technique is used to provide a description of the physical and thermodynamic properties of the cloud of warm gases formed when the explosive detonates. Particle dispersion is treated as a stochastic process which is simulated using a discrete time Lagrangian Monte Carlo method. The stochastic process approach permits a more fundamental treatment of buoyancy effects, calm winds and spatial variations in meteorological conditions. Computational requirements of the three-dimensional simulation are substantially reduced by using a conceptualization in which each Monte Carlo particle represents a small puff that spreads according to a Gaussian law in the horizontal directions. ERAD was evaluated against dosage and deposition measurements obtained during Operation Roller Coaster. The predicted contour areas average within about 50% of the observations. The validation results confirm the model`s representation of the physical processes.

  5. Toward a Thermal Disequilibrium Multiphase Model for High Explosives Containing Metallic Particles

    NASA Astrophysics Data System (ADS)

    Baudin, Gerard; Lefrancois, Alexandre; Saurel, Richard; Petitpas, Fabien; Le Metayer, Olivier; Massoni, Jacques; Belski, Vladimir M.; Zotov, Eugène

    2010-10-01

    To investigate the effects of explosive composition on Al combustion, in particular regarding its oxygen balance, several liquid mixtures are experimentally studied with varying oxygen balance. They are then loaded with Al particles and the velocity of detonation (VOD) is recorded. Computational results with the help of conventional Chapman Jouguet (CJ) codes are compared but fail to reproduce experimental observations. A new multiphase flow model out of thermal equilibrium is then considered. Two options are considered as limiting cases: stiff thermal relaxation and vanishing heat exchange between Al and detonation products. With this last option, predictions are in excellent agreement with the experiments. This suggests that temperature disequilibrium plays a major role in heterogeneous explosives detonation dynamics.

  6. An Investigation of the Material Hazard of Some Insensitive High Explosives

    DTIC Science & Technology

    1991-07-01

    on the use of nuclear magne••c resonance spectroscopy to define molecular structure. After post-doctoral studies for two yars in the USA he taught in...Rotter testing, as well as for emitted light from some samples during drop weight testing [381 and for frequency of explosion versus energy in BAM...Defense (1984). Military standard. Fuze, design, safty , criteria for, MIL-STD-1316C. 22. UK Ordnance Board (1982). Princples for the design of fuzng

  7. Hydrophone Investigations of Earthquakes and Explosion Generated High-Frequency Seismic Phases

    DTIC Science & Technology

    1989-06-30

    18. SUBJECT TERMS (Continue on reverse if nceary and identify by block number) FIELD GROUP SUB-GROUP Earthquakes, Seismology , Velocities, Hydrophanes...AFOSR-86-0039 Principal Investigator and Phone Number: Daniel A. Walker Chairman, Seismology Division 808-948-8767 Program Manager and Phone Number...Walker, D.A., Deep ocean seismology , Eos, 65, 2-3. A discussion of the advantages of recording earthquakes and explosions on the ocean floor. 1985 Walker

  8. Qualitative Assessment of the Ignition of Highly Flammable Fuels by Primary Explosives,

    DTIC Science & Technology

    1983-06-01

    primary explosives used in the investigation are listed below:- basic lead azide lead azide lead styphnate barium styphnate potassium picrate lead...in Bakelite Tubes Basic Lead Azide w Lead Styphnate LDNR Barium Styphnate I Flash Composition Potassium Picrate I TABLE 3 IGNITION OF HEXANE SOAKED...Flammability Nichrome Bridgewire in Aluminium Tube Potassium Picrate X LDVR X Barium Styphnate X Tetracene X 200 mq Lead Styphnate X 400 mq Lead

  9. Compilation of Blast Parameters of Selected High Explosives, Propellants, and Pyrotechnics in Surface Burst Configurations.

    DTIC Science & Technology

    1987-01-01

    PBXC-203 Cylindrical 1.4, 2.8, 2.9, 5.2, 5.6, and 10.4 PBXN -106 (Precoat) Otrhorhombic 27.22, 45.36, and 90.72 PBXN -109 (Precoat) Orthorhombic 27.22...Conclusions ................................................... 166 PBXN -106 (PRECOAT) AND PBXN -109 (PRECOAT) EXPLOSIVES ............ 171 Objective...Distance for PBXN -106 (Precoat) for, 27.22 kg Orthorhombic Shipping Container .............. 176 77. Peak Pressure and Scaled Positive Impulse versus

  10. A Multipathway Model for High Explosives and Barium Transport Using GoldSim

    NASA Astrophysics Data System (ADS)

    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

  11. Potassium Nitraminofurazan Derivatives: Potential Green Primary Explosives with High Energy and Comparable Low Friction Sensitivities.

    PubMed

    Li, Ying; Huang, Haifeng; Shi, Yameng; Yang, Jun; Pan, Renming; Lin, Xiangyang

    2017-05-29

    Lead-based primary explosives were widely applied in military and civilian ammunition, which have subsequently caused serious environmental and health-related problems. Therefore, the development of green alternatives for the lead-based primary explosives has been one of the major focuses in the field of energetic materials. Four potassium salts based on nitraminofurazan have been easily synthesized and show excellent comprehensive performances. Among them, potassium 3-dinitromethyl-4-nitraminofurazan (K2 DNMNAF, 1) showed better thermal stability (Td : 281.4 °C), higher density (2.174 g cm(-3) ), and lower friction sensitivities (72 N) than that of potassium 4,5-bis(dinitromethyl)furoxanate (K2 BDNMF, Td : 218.3 °C, density: 2.130 g cm(-3) , FS: 5 N, P: 27.3 GPa, vD : 7759 m s(-1) ); furthermore, it displayed comparable detonation performances (P: 27.2 GPa, vD : 7758 m s(-1) ). The promising properties of these salts make this kind of material a competitive alternative to lead azide as a primary explosive. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Comparison of Mobile Laboratory screening method for the detection of high explosives with EPA SW 846 method 8330

    SciTech Connect

    Swanson, A.L.; Roberts, J.B.; Canavan, H.E.; Kelly, L.A.

    1996-03-01

    The current EPA SW-846 method for High Explosives (HE) analysis is not well suited to on-site analytical work. The method in general is too complex and time dependent to function well in a quick turn around mode. The Mobile Chemical Analytical Laboratory project at Los Alamos National Laboratory (LANL) has used a modified analytical method to generate quick turn around data to address Department of Transportation (DOT) shipping requirements, and with appropriate modifications to the QA/QC oversight of the method is well suited to deliver high quality quantitative data.

  13. Modeling the Structural Response from a Propagating High Explosive Using Smooth Particle Hydrodynamics

    SciTech Connect

    Margraf, J

    2012-06-12

    This report primarily concerns the use of two massively parallel finite element codes originally written and maintained at Lawrence Livermore National Laboratory. ALE3D is an explicit hydrodynamics code commonly employed to simulate wave propagation from high energy scenarios and the resulting interaction with nearby structures. This coupled response ensures that a structure is accurately applied with a blast loading varying both in space and time. Figure 1 illustrates the radial outward propagation of a pressure wave due to a center detonated spherical explosive originating from the lower left. The radial symmetry seen in this scenario is lost when instead a cylindrocal charge is detonated. Figure 2 indicates that a stronger, faster traveling pressure wave occurs in the direction of the normal axis to the cylinder. The ALE3D name is derived because of the use of arbitrary-Lagrange-Eulerian elements in which the mesh is allowed to advect; a process through which the mesh is modified to alleviate tanlging and general mesh distortion often cuased by high energy scenarios. The counterpart to an advecting element is a Lagrange element, whose mesh moves with the material. Ideally all structural components are kept Lagrange as long as possible to preserve accuracy of material variables and minimize advection related errors. Advection leads to mixed zoning, so using structural Lagrange elements also improves the visualization when post processing the results. A simplified representation of the advection process is shown in Figure 3. First the mesh is distorted due to material motion during the Lagrange step. The mesh is then shifted to an idealized and less distorted state to prevent irregular zones caused by the Lagrange motion. Lastly, the state variables are remapped to the elements of the newly constructed mesh. Note that Figure 3 represents a purely Eulerian mesh relaxation because the mesh is relocated back to the pre-Lagrange position. This is the case when the

  14. Parametric Explosion Spectral Model

    SciTech Connect

    Ford, S R; Walter, W R

    2012-01-19

    Small underground nuclear explosions need to be confidently detected, identified, and characterized in regions of the world where they have never before occurred. We develop a parametric model of the nuclear explosion seismic source spectrum derived from regional phases that is compatible with earthquake-based geometrical spreading and attenuation. Earthquake spectra are fit with a generalized version of the Brune spectrum, which is a three-parameter model that describes the long-period level, corner-frequency, and spectral slope at high-frequencies. Explosion spectra can be fit with similar spectral models whose parameters are then correlated with near-source geology and containment conditions. We observe a correlation of high gas-porosity (low-strength) with increased spectral slope. The relationship between the parametric equations and the geologic and containment conditions will assist in our physical understanding of the nuclear explosion source.

  15. APPLICATION OF THE EMBEDDED FIBER OPTIC PROBE IN HIGH EXPLOSIVE DETONATION STUDIES: PBX-9502 AND LX-17

    SciTech Connect

    Hare, D; Goosman, D; Lorenz, K; Lee, E

    2006-09-26

    The Embedded Fiber Optic probe directly measures detonation speed continuously in time, without the need to numerically differentiate data, and is a new tool for measuring time-dependent as well as steady detonation speed to high accuracy. It consists of a custom-design optical fiber probe embedded in high explosive. The explosive is detonated and a refractive index discontinuity is produced in the probe at the location of the detonation front by the compression of the detonation. Because this index-jump tracks the detonation front a measurement of the Doppler shift of laser light reflected from the jump makes it possible to continuously measure detonation velocity with high spatial and temporal resolution. We have employed this probe with a Fabry-Perot-type laser Doppler velocimetry system additionally equipped with a special filter for reducing the level of non-Doppler shifted light relative to the signal. This is necessary because the index-jump signal is relatively weak compared to the return expected from a well-prepared surface in the more traditional and familiar example of material interface velocimetry. Our observations were carried out on a number of explosives but this work is focused on our results on PBX-9502 (95% TATB, 5% Kel-F) and LX-17 (92.5% TATB, 7.5% Kel-F) at varying initial charge density. Our measurements reveal a density dependence significantly lower than previous quoted values and lower than theoretical calculations. Our limited data on detonation speed dependence on wave curvature is in reasonable agreement with previous work using more standard methods and confirms deviation from the Wood-Kirkwood theoretical formula.

  16. High CO2 in MORB - a link to explosive submarine eruptions?

    NASA Astrophysics Data System (ADS)

    Helo, C.; Longpré, M.; Shimizu, N.; Clague, D. A.; Stix, J.

    2009-12-01

    We analyzed volatile (CO2, H2O, S, F, Cl), and other trace elements, using the Cameca IMS 1280 and the Cameca 3F secondary ion mass spectrometer, in carefully selected plagioclase-hosted melt inclusions and matrix glass from mid-ocean ridge basalt (MORB) hyaloclastite sequences erupted from Axial caldera, Juan de Fuca Ridge (JdFR). The hyaloclastites were sampled at 1400 m below sea-level, and are inferred to result from a series of small pyroclastic eruptions. The trace elements reveal variations from normal to transitional MORB for Axial caldera (e.g., Nb = 1.1-6.5 ppm, Zr/Nb = 9-39). The CO2 concentrations in the melt inclusions range from 260 to 9160 ppm, with 16 out of 47 analyzed inclusions reaching > 1000 ppm. Surface contamination was ruled out by very low CO2 concentrations measured in adjacent plagioclase hosts (< 30 ppm). Such high values are consistent with the initial CO2 content estimated for N- and T-MORBs from the Mid-Atlantic Ridge [Hekinian et al, 2000. Journal of Volcanology and Geothermal Research 98]. When plotted together, CO2 and H2O define a vertical trend suggesting decompression degassing, with apparent vapour saturation pressures ranging from 57 to > 600 MPa. We recognize two possible scenarios: (1) limited degassing during early stages of magma ascent, culminating in supersaturation and sudden, rapid bubble growth at shallower levels, or (2) open-system degassing accompanied by bubble growth and separation as magma rises. The close spatial occurrence of high- and low-CO2 inclusions (< 1000 ppm) within single crystals may argue towards the first interpretation. Saturation pressures for low-CO2 inclusions are consistent with pressures expected within the present day magma reservoir beneath Axial (~ 70-160 MPa). The matrix glass is oversaturated with respect to the depth of eruption; CO2 concentrations vary from 87 to 248 ppm, yielding saturation pressures between 14 MPa and 54 MPa. Water concentrations in the inclusions range from 0.05 to

  17. A Risk Management Framework to Characterize Black Swan Risks: A Case Study of Lightning Effects on Insensitive High Explosives

    NASA Astrophysics Data System (ADS)

    Sanders, Gary A.

    Effective and efficient risk management processes include the use of high fidelity modeling and simulation during the concept exploration phase as part of the technology and risk assessment activities, with testing and evaluation tasks occurring in later design development phases. However, some safety requirements and design architectures may be dominated by the low probability/high consequence "Black Swan" vulnerabilities that require very early testing to characterize and efficiently mitigate. Failure to address these unique risks has led to catastrophic systems failures including the space shuttle Challenger, Deepwater Horizon, Fukushima nuclear reactor, and Katrina dike failures. Discovering and addressing these risks later in the design and development process can be very costly or even lead to project cancellation. This paper examines the need for risk management process adoption of early hazard phenomenology testing to inform the technical risk assessment, requirements definition and conceptual design. A case study of the lightning design vulnerability of the insensitive high explosives being used in construction, mining, demolition, and defense industries will be presented to examine the impact of this vulnerability testing during the concept exploration phase of the design effort. While these insensitive high explosives are far less sensitive to accidental initiation by fire, impact, friction or even electrical stimuli, their full range of sensitivities have not been characterized and ensuring safe engineering design and operations during events such as lightning storms requires vulnerability testing during the risk assessment phase.

  18. Overview of Explosive Initiators

    DTIC Science & Technology

    2015-11-01

    Primary explosive Initiator Detonator Primer Blasting cap Lead azide Lead styphnate 16. SECURITY CLASSIFICATION OF...Conclusions 13 References 15 Distribution List 17 FIGURES 1 Decomposition reaction of lead azide in the presence of carbon dioxide and water (ref...the world, currently the most popular are lead azide (Pb(N3)2) and lead styphnate (both normal and basic forms) and tetrazene. With its high explosive

  19. High-explosive cratering analogs for bowl-shaped, central uplift, and multiring impact craters

    NASA Technical Reports Server (NTRS)

    Roddy, D. J.

    1976-01-01

    The paper describes six experimental explosion craters in terms of their basic morphology, subsurface structural deformation, and surrounding ejecta blanket. These craters exhibit one or more of the following features: bowl shapes with underlying breccia lens, central uplifts, multirings, terraced walls, rim strata, zones of concentric rim deformation, inner continuous ground cover of ejecta blankets formed by overturned flaps, secondary cratering, and fused alluvium. These craters were formed by large shock wave energy transfers at or near zero heights-of-burst, and it is possible that impact craters with analogous morphologic and structural features may have formed under similar surface energy transfer conditions.

  20. Water Temperature and Concentration Measurements Within the Expanding Blast Wave of a High Explosive

    DTIC Science & Technology

    2011-03-15

    I/Iref ) every 50 μs (20 kHz repetition rate). RP-3 exploding bridgewire detonator (Teledyne RISI, 29 mg pentaerythritol tetranitrate ( PETN )) and the...main charge, which was either 12.7 or 25.4 mm right circular cylinders of PETN . The PETN charges were pressed to near theoretical maximum density...main charge would stick to the surface without the need for other adhesives. Care was taken to construct the explosive assembly out of pure PETN so

  1. Detonation of insensitive high explosives by a Q-switched ruby laser.

    NASA Technical Reports Server (NTRS)

    Yang, L. C.; Menichelli, V. J.

    1971-01-01

    Immediate longitudinal detonations have been observed in confined small-diameter columns of PETN, RDX, and tetryl by using a focused Q-switched ruby laser. The energy ranged from 0.8 to 4.0 J in a pulse width of 25 nsec. A 1000-A-thick aluminum film deposited on a glass window was used to generate a shock wave at the window-explosive interface when irradiated by the laser. In some cases, steady-state detonations were reached in less than .5 microsec with less than 10% variation in the detonation velocity.

  2. Infrasonic observations and modeling of the Minor Uncle High Explosive event

    SciTech Connect

    Whitaker, R.; Noel, S.D.; Meadows, W.R.

    1994-09-01

    Minor Uncle was a Department of Defense sponsored explosive test of 2440 tons of ammonium nitrate and fuel oil (ANFO) executed on June 10, 1993, at White Sands Missile Range, NM. Los Alamos National Laboratory made infrasonic observations of this event at three stations: Los Alamos, NM, 250 km range; St. George, UT, 750 km range; and the Nevada Test Site, NV, 928 km range. All three stations obtained positive results and had very low background noise levels. Data from all stations will be presented, and normal mode calculations of the wave propagation, including upper atmospheric winds, to St. George will be compared to the data.

  3. Evaluation of SW846 Method 8330 for Characterization of Sites Contaminated with Residues of High Explosives

    DTIC Science & Technology

    1993-06-01

    Photodegradation TNB 02 N NO2 Microbial Degradation ~orpubicelease and scil.; its 02 disribtin is unlimited. NI Microbial Degradation a 4A 2A 3,5- DNA CH3 CH3 a...Environmental transformafton products such as TNB, 2-amino- and 4-amino- DNTand3,5-dinitroanlline(3,5, DNA )werealsofrequerttyobserved. Explosives- contaminated...water samples generally contained RDX, HMX and/or TNT. Transformation products commonly found included TNB, DNB, 2,4- and 2,6- DNT, 3,5- DNA and the

  4. Quantitative understanding of explosive stimulus transfer

    NASA Technical Reports Server (NTRS)

    Schimmel, M. L.

    1973-01-01

    The mechanisms of detonation transfer across hermetically sealed interfaces created by necessary interruptions in high explosive trains, such as at detonators to explosive columns, field joints in explosive columns, and components of munitions fuse trains are demostrated. Reliability of detonation transfer is limited by minimizing explosive quantities, the use of intensitive explosives for safety, and requirements to propagate across gaps and angles dictated by installation and production restraints. The major detonation transfer variables studied were: explosive quanity, sensitivity, and thickness, and the separation distances between donor and acceptor explosives.

  5. Determining the TNT equivalence of gram-sized explosive charges using shock-wave shadowgraphy and high-speed video recording

    NASA Astrophysics Data System (ADS)

    Hargather, Michael

    2005-11-01

    Explosive materials are routinely characterized by their TNT equivalence. This can be determined by chemical composition calculations, measurements of shock wave overpressure, or measurements of the shock wave position vs. time. However, TNT equivalence is an imperfect criterion because it is only valid at a given radius from the explosion center (H. Kleine et al., Shock Waves 13(2):123-138, 2003). Here we use a large retroreflective shadowgraph system and a high-speed digital video camera to image the shock wave and record its location vs. time. Optical data obtained from different explosions can be combined to determine a characteristic shock wave x-t diagram, from which the overpressure and the TNT equivalent are determined at any radius. This method is applied to gram-sized triacetone triperoxide (TATP) charges. Such small charges can be used inexpensively and safely for explosives research.

  6. Characterization of ANFO explosive by high accuracy ESI(±)-FTMS with forensic identification on real samples by EASI(-)-MS.

    PubMed

    Hernandes, Vinicius Veri; Franco, Marcos Fernado; Santos, Jandyson Machado; Melendez-Perez, Jose J; de Morais, Damila Rodrigues; Rocha, Werickson Fortunato de Carvalho; Borges, Rodrigo; de Souza, Wanderley; Zacca, Jorge Jardim; Logrado, Lucio Paulo Lima; Eberlin, Marcos Nogueira; Correa, Deleon Nascimento

    2015-04-01

    Ammonium nitrate fuel oil (ANFO) is an explosive used in many civil applications. In Brazil, ANFO has unfortunately also been used in criminal attacks, mainly in automated teller machine (ATM) explosions. In this paper, we describe a detailed characterization of the ANFO composition and its two main constituents (diesel and a nitrate explosive) using high resolution and accuracy mass spectrometry performed on an FT-ICR-mass spectrometer with electrospray ionization (ESI(±)-FTMS) in both the positive and negative ion modes. Via ESI(-)-MS, an ion marker for ANFO was characterized. Using a direct and simple ambient desorption/ionization technique, i.e., easy ambient sonic-spray ionization mass spectrometry (EASI-MS), in a simpler, lower accuracy but robust single quadrupole mass spectrometer, the ANFO ion marker was directly detected from the surface of banknotes collected from ATM explosion theft.

  7. Global disturbances of the ionosphere caused by the electric field from the high-altitude nuclear explosion 'Starfish' on July 9, 1962. I, II

    NASA Astrophysics Data System (ADS)

    Tsedilina, E. E.; Shashun'kina, V. M.

    1990-10-01

    The theory of the formation of an artifical radiation belt of high-energy electrons in the magnetosphere is used to examine possible ionospheric effects from the electric field generated by the Starfish nuclear test explosion over Johnston Island on July 9, 1962. A region in the Northern Hemisphere is identified where the explosion led to a drop in electron density in the F-region maximum by about 20 percent and a lowering of the layer by 20-30 km in the course of one hour after the explosion. The F-layer gradually came back to normal in the following hour. It is suggested that, in the initial period after the explosion, this effect was associated with the western electric field, which caused the lowering of the F-layer, as well as with changes in the recombination-diffusion balance in this layer.

  8. Explosive detection using high-volume vapor sampling and analysis by trained canines and ultra-trace detection equipment

    NASA Astrophysics Data System (ADS)

    Fisher, Mark; Sikes, John; Prather, Mark

    2004-09-01

    The dog's nose is an effective, highly-mobile sampling system, while the canine olfactory organs are an extremely sensitive detector. Having been trained to detect a wide variety of substances with exceptional results, canines are widely regarded as the 'gold standard' in chemical vapor detection. Historically, attempts to mimic the ability of dogs to detect vapors of explosives using electronic 'dogs noses' has proven difficult. However, recent advances in technology have resulted in development of detection (i.e., sampling and sensor) systems with performance that is rapidly approaching that of trained canines. The Nomadics Fido was the first sensor to demonstrate under field conditions the detection of landmines with performance approaching that of canines. More recently, comparative testing of Fido against canines has revealed that electronic vapor detection, when coupled with effective sampling methods, can produce results comparable to that of highly-trained canines. The results of these comparative tests will be presented, as will recent test results in which explosives hidden in cargo were detected using Fido with a high-volume sampling technique. Finally, the use of canines along with electronic sensors will be discussed as a means of improving the performance and expanding the capabilities of both methods.

  9. The significance of interaction potentials of water with other molecules in the EOS of high explosives products

    SciTech Connect

    van Thiel, M.; Ree, F.H.; Haselman, L.C. Jr.

    1993-07-01

    The chemical equilibrium and thermodynamic properties of detonated explosive mixtures at high temperature (T) and pressure (P) depend critically on all interactions between the major products. Improvements in the homomolecular interaction of nitrogen, carbon-dioxide, and condensed carbon have had significant effects on detonation properties of LX-14 (an HMX formulation). Extensive work on O, N, and C products also showed the importance of including high temperature unstable species in determining the potential-constant of the major products of detonation. That work also showed the need to improve the unlike pair interaction constants in our statistical mechanical chemical equilibrium theory (CHEQ). Thirdly, a recent comparison of experimental and theoretical detonation velocities (D) indicated that the original set of interaction potentials used contains canceling errors that limit the overall effectiveness of the code as a predictor of high P and T properties of reactive mixtures. This study proceeds from explosives with simple product mixtures, RX-23-AB, HNB, and PETN, to HMX-like mixtures. The present set of potential constants is compared to the experimental EOS used for a number of experimental systems that use LX-14.

  10. Numerical model investigation for potential methane explosion and benzene vapor intrusion associated with high-ethanol blend releases.

    PubMed

    Ma, Jie; Luo, Hong; Devaull, George E; Rixey, William G; Alvarez, Pedro J J

    2014-01-01

    Ethanol-blended fuel releases usually stimulate methanogenesis in the subsurface, which could pose an explosion risk if methane accumulates in a confined space above the ground where ignitable conditions exist. Ethanol-derived methane may also increase the vapor intrusion potential of toxic fuel hydrocarbons by stimulating the depletion of oxygen by methanotrophs, and thus inhibiting aerobic biodegradation of hydrocarbon vapors. To assess these processes, a three-dimensional numerical vapor intrusion model was used to simulate the degradation, migration, and intrusion pathway of methane and benzene under different site conditions. Simulations show that methane is unlikely to build up to pose an explosion hazard (5% v/v) if diffusion is the only mass transport mechanism through the deeper vadose zone. However, if methanogenic activity near the source zone is sufficiently high to cause advective gas transport, then the methane indoor concentration may exceed the flammable threshold under simulated conditions. During subsurface migration, methane biodegradation could consume soil oxygen that would otherwise be available to support hydrocarbon degradation, and increase the vapor intrusion potential for benzene. Vapor intrusion would also be exacerbated if methanogenic activity results in sufficiently high pressure to cause advective gas transport in the unsaturated zone. Overall, our simulations show that current approaches to manage the vapor intrusion risk for conventional fuel released might need to be modified when dealing with some high ethanol blend fuel (i.e., E20 up to E95) releases.

  11. Summary of efficiency testing of standard and high-capacity high-efficiency particulate air filters subjected to simulated tornado depressurization and explosive shock waves

    SciTech Connect

    Smith, P.R.; Gregory, W.S.

    1985-04-01

    Pressure transients in nuclear facility air cleaning systems can originate from natural phenomena such as tornadoes or from accident-induced explosive blast waves. This study was concerned with the effective efficiency of high-efficiency particulate air (HEPA) filters during pressure surges resulting from simulated tornado and explosion transients. The primary objective of the study was to examine filter efficiencies at pressure levels below the point of structural failure. Both standard and high-capacity 0.61-m by 0.61-m HEPA filters were evaluated, as were several 0.2-m by 0.2-m HEPA filters. For a particular manufacturer, the material release when subjected to tornado transients is the same (per unit area) for both the 0.2-m by 0.2-m and the 0.61-m by 0.61-m filters. For tornado transients, the material release was on the order of micrograms per square meter. When subjecting clean HEPA filters to simulated tornado transients with aerosol entrained in the pressure pulse, all filters tested showed a degradation of filter efficiency. For explosive transients, the material release from preloaded high-capacity filters was as much as 340 g. When preloaded high-capacity filters were subjected to shock waves approximately 50% of the structural limit level, 1 to 2 mg of particulate was released.

  12. Skin explosion of double-layer conductors in fast-rising high magnetic fields

    SciTech Connect

    Chaikovsky, S. A. Datsko, I. M.; Labetskaya, N. A.; Ratakhin, N. A.

    2014-04-15

    An experiment has been performed to study the electrical explosion of thick cylindrical conductors using the MIG pulsed power generator capable of producing a peak current of 2.5 MA within 100 ns rise time. The experimental goal was to compare the skin explosion of a solid conductor with that of a double-layer conductor whose outer layer had a lower conductivity than the inner one. It has been shown that in magnetic fields of peak induction up to 300 T and average induction rise rate 3 × 10{sup 9} T/s, the double-layer structure of a conductor makes it possible to achieve higher magnetic induction at the conductor surface before it explodes. This can be accounted for, in particular, by the reduction of the ratio of the Joule heat density to the energy density of the magnetic field at the surface of a double-layer conductor due to redistribution of the current density over the conductor cross section.

  13. Skin explosion of double-layer conductors in fast-rising high magnetic fields

    NASA Astrophysics Data System (ADS)

    Chaikovsky, S. A.; Oreshkin, V. I.; Datsko, I. M.; Labetskaya, N. A.; Ratakhin, N. A.

    2014-04-01

    An experiment has been performed to study the electrical explosion of thick cylindrical conductors using the MIG pulsed power generator capable of producing a peak current of 2.5 MA within 100 ns rise time. The experimental goal was to compare the skin explosion of a solid conductor with that of a double-layer conductor whose outer layer had a lower conductivity than the inner one. It has been shown that in magnetic fields of peak induction up to 300 T and average induction rise rate 3 × 109 T/s, the double-layer structure of a conductor makes it possible to achieve higher magnetic induction at the conductor surface before it explodes. This can be accounted for, in particular, by the reduction of the ratio of the Joule heat density to the energy density of the magnetic field at the surface of a double-layer conductor due to redistribution of the current density over the conductor cross section.

  14. Heavy and Superheavy Elements Production in High Intensive Neutron Fluxes of Explosive Process

    NASA Astrophysics Data System (ADS)

    Lutostansky, Yu. S.; Lyashuk, V. I.; Panov, I. V.

    2015-06-01

    Mathematical model of heavy and superheavy nuclei production in intensive pulsed neutron fluxes of explosive process is developed. The pulse character of the process allows dividing it in time into two stages: very short rapid process of multiple neutron captures with higher temperature and very intensive neutron fluxes, and relatively slower process with lesser temperature and neutron fluxes. The model was also extended for calculation of the transuranium yields in nuclear explosions takes into account the adiabatic character of the process, the probabilities of delayed fission, and the emission of delayed neutrons. Also the binary starting target isotopes compositions were included. Calculations of heavy transuranium and transfermium nuclei production were made for "Mike", "Par" and "Barbel" experiments, performed in USA. It is shown that the production of transfermium neutron-rich nuclei and superheavy elements with A ~ 295 is only possible when using binary mixture of starting isotopes with the significant addition of heavy components, such as long-lived isotopes of curium, or californium.

  15. Paroxysmal dome explosion during the Merapi 2010 eruption: Processes and facies relationships of associated high-energy pyroclastic density currents

    NASA Astrophysics Data System (ADS)

    Komorowski, Jean-Christophe; Jenkins, Susanna; Baxter, Peter J.; Picquout, Adrien; Lavigne, Franck; Charbonnier, Sylvain; Gertisser, Ralf; Preece, Katie; Cholik, Noer; Budi-Santoso, Agus; Surono

    2013-07-01

    An 11-minute sequence of laterally-directed explosions and retrogressive collapses on 5 November 2010 at Merapi (Indonesia) destroyed a rapidly-growing dome and generated high-energy pyroclastic density currents (PDCs) spreading over 22 km2 with a runout of 8.4 km while contemporaneous co-genetic valley-confined PDCs reached 15.5 km. This event formed Stage 4 of the multi-stage 2010 eruption, the most intense eruptive episode at Merapi since 1872. The deposits and the widespread devastating impact of associated high-energy PDCs on trees and buildings show striking similarities with those from historical volcanic blasts (Montagne Pelée, Martinique, Bezymianny, Russia, Mount St. Helens, USA, Soufrière Hills, Montserrat). We provide data from stratigraphic and sedimentologic analyses of 62 sections of the first unequivocal blast-like deposits in Merapi's recent history. We used high resolution satellite imagery to map eruptive units and flow direction from the pattern of extensive tree blowdown. The stratigraphy of Stage 4 consists of three depositional units (U0, U1, U2) that we correlate to the second, third and fourth explosions of the seismic record. Both U1 and U2 show a bi-partite layer stratigraphy consisting each of a lower L1 layer and an upper L2 layer. The lower L1 layer is typically very coarse-grained, fines-poor, poorly-sorted and massive, and was deposited by the erosive waxing flow head. The overlying L2 layer is much finer grained, fines-rich, moderately to well-sorted, with laminar to wavy stratification. L2 was deposited from the waning upper part and wake of the PDC. Field observations indicate that PDC height reached ~ 330 m with an internal velocity of ~ 100 m s- 1 within 3 km from the source. The summit's geometry and the terrain morphology formed by a major transversal ridge and a funneling deep canyon strongly focused PDC mass towards a major constriction, thereby limiting the loss of kinetic energy. This favored elevated PDC velocities and

  16. High resolution Coulomb explosion spectra and angular distributions of fragment ions of N 2 in a femtosecond laser field

    NASA Astrophysics Data System (ADS)

    Shi, Mingyuan; Huang, Shaochuan; Xi, Wei; Liu, Zuoye; Du, Hongchuan; Ding, Baowei; Hu, Bitao

    2017-03-01

    Femtosecond laser field-induced ionization and Coulomb explosion are systematically investigated using high-resolution time-of-flight mass spectroscopy. Meanwhile a good alignment of the N2 is achieved geometrically. Based on the energy and momentum conservation laws, the events from different Coulomb explosion channels are identified accurately and further used to obtain the Kinetic Energy Release (KER) by the created molecular ion pairs and the angular distributions of the fragment ions. The KERs measured at laser intensities varying from 4 × 10^{14} W/cm2 to 2 × 10^{15} W/cm2 are found to stay constant. The angular distributions are measured at laser intensity of 9 × 10^{14} W/cm2. The atomic ions N+, N^{2+} and N^{3+} exhibit highly anisotropic distributions and for higher charge state, the angular distributions become narrower. With good exclusion of channel N(1,0), the non-zeroes normal to the laser polarization vector in channel N(1,1) still exist, which indicates the presence of geometric alignments (GA). The elusive shrink structure at θ=0° for channels N(1,1), N(1,2) and N(2,3) is observed, which implies that the non-sequential process exists, and the electron rescattering plays role in the ionization process.

  17. Time resolved study of light emitted by detonation arrival at the surface of high explosives in various environments

    SciTech Connect

    Bahl, K.L.; Von Holle, W.G.

    1988-03-24

    In search of a way to accurately measure time of arrival of detonation fronts, we have been using an electronic streak camera equipped with a light intensifier to record intensity-time histories of the light that is emitted when a detonation front emerges through the surface of high explosives in contact with various environments. Streak records at writing speeds up to 100 mm/..mu..s were obtained of detonations in air, argon, water and vacuum when the high explosive (HE) was either bare or covered with materials such as: aluminum silicofluoride (Al/sub 2/(SiF/sub 6/)/sub 3/), PETN powder, polymethyl methacrylate (PMM), glass, aluminum foils, transparent tape, black ink, potassium chloride crystals, sodium chloride crystals and lithium fluoride crystals. The result of this study is that we believe that we can measure the time of arrival of a detonation front at a bare HE surface in air to within a few nanoseconds. 12 refs., 10 figs., 1 tab.

  18. Innovative assistant extraction of flavonoids from pine (Larix olgensis Henry) needles by high-density steam flash-explosion.

    PubMed

    Song, Hongdong; Yang, Ruijin; Zhao, Wei; Katiyo, Wendy; Hua, Xiao; Zhang, Wenbin

    2014-04-30

    High-density steam flash-explosion (HDSF) was first employed to extract flavonoids from pine needles. The HDSF treatment was performed at a steam pressure of 0.5-2.0 MPa for 20-120 s. Scanning electron microscopy and high-performance liquid chromatography combined with photodiode-array detection and electrospray ionization mass spectrometry (HPLC-DAD-ESI-MS) were used to characterize the morphological changes and analyze flavonoids of pine needles before and after HDSF treatment. Our results indicated that, after steam explosion at 1.5 MPa for 60 s, the flavonoids extracted reached 50.8 rutin equivalents mg/g dry weight, which was 2.54-fold as that of the untreated sample. HDSF pretreatment caused the formation of large micropores on the pine needles and production of particles, as well as the removal of wax layers. Compared to microwave-assisted, ultrasound-assisted, and solvent extraction, HDSF pretreatment took only 30 min to reach a maximum yield of 47.0 rutin equivalents mg/g flavonoids extract after pine needles were treated at 1.5 MPa for 80 s. In addition, after HDSF treatment, the aglycones were 3.17 times higher than that of untreated pine needles, while glycosides were lower by 57% (in HPLC-DAD individuals' sum) due to hydrolysis of flavonoids glycosides. It can be concluded that HDSF is a practical pretreatment for extraction of flavonoids and conversion in the healthy food and pharmaceutical industries.

  19. The spectacular evolution of Supernova 1996al over 15 years: a low energy explosion of a stripped massive star in a highly structured environment

    NASA Astrophysics Data System (ADS)

    Benetti, Stefano

    2016-06-01

    The final fate of massive stars is not well explored and depending on the stellar mass may have very much different outputs, ranging from very energetic explosions (e.g. GRB-SNe) to direct collapse on black-holes with very weak or not explosion at all (Heger, Woosley, & Baraffe, 2005). Here I present the case of SN 1996al. I describe the physical properties of this luminous supernova in the framework of a very weak explosion (kinetic energy of 1.6 x 10^(50 erg)), where the bolometric luminosity is sustained by the conversion of the kinetic energy into radiation thanks to the interaction between a low mass ( 1.15 M_{⊙}) , 87% of which is Helium, the remaining is Hydrogen) symmetric ejecta with an highly asymmetric circumstellar material. The detection of Hα emission in pre-explosion archive images suggests that the progenitor of SN 1996al was most likely a massive star ( 25 M_{⊙}) ZAMS) that had lost a large fraction of its hydrogen envelope before explosion, and was hence embedded in a H-rich cocoon. The low-mass ejecta and modest kinetic energy of the explosion are then explained with massive fallback of material into the compact remnant, a 7 - 8 M_{⊙}) black hole. Finally, I will try to place this particularly interesting SN in the framework of the SNIIn zoo.

  20. A platform for on-site environmental analysis of explosives using high performance liquid chromatography with UV absorbance and photo-assisted electrochemical detection.

    PubMed

    Marple, Ronita L; Lacourse, William R

    2005-04-30

    High-performance liquid chromatography with photo-assisted electrochemical detection (HPLC-PAED) is used in conjunction with ultraviolet absorbance (UV) detection for determining explosives in environmental samples. The system utilizes an on-line solid-phase extraction technique for sample pretreatment (i.e., fractionation and concentration), thus reducing the required ground water sample size from 1L to 2mL and minimizing sample handling. Limits of detection for explosives using solid-phase extraction and PAED range from 0.0007 to 0.4mug/L, well below those achieved with UV detection for several important explosives (e.g., RDX). The method has demonstrated good accuracy, precision, and recovery for all tested explosives, thus proving that the method is suitable for evaluation of explosives in ground water with competitive advantages over the U.S. Environmental Protection Agency (EPA) Method 8330. A system adaptable for the on-site environmental analysis of explosives has been developed and validated.

  1. Modeling High Explosives with the Method of Cells and Mori-Tanaka Effective Medium Theories

    NASA Astrophysics Data System (ADS)

    Clements, B. E.; Mas, E. M.

    2002-07-01

    The Method of Cells (MOC) has been applied to a PBX 9501 composite, consisting of large explosive grains embedded in a small grain-binder mixture, to determine its thermal-mechanical properties. To treat the bimodal size distribution of grains, in the framework of the MOC, we assign one of eight MOC cells to model the effects of large grains and the remaining seven cells to model the small grain-binder mixture. We have applied a modified Mori-Tanaka effective medium theory to model the small grain-binder mixture. Spherical as well as randomly oriented ellipsoidal grains can be treated. This theory allows us to model the individual properties of the constituents: binder viscoelasticity, and grain elastic-plastic-damage behavior. Interfacial debonding between the grains and binder can be incorporated as needed. The method's predictions are compared to uniaxial measurements. [Research supported by the USDOE under contract W-7405-ENG-36.

  2. Dynamics of High Sound-Speed Metal Confiners Driven By Non-Ideal High-Explosive Detonation

    SciTech Connect

    Short, Mark; Jackson, Scott I.

    2015-01-23

    range of wall velocities where the overlap occurs increases as the ratio of the wall thickness to inner diameter decreases. In conclusion, this is in contrast to ideal high explosives, where the outer wall velocity histories are only similar when the geometric scale factor (in this case a factor of 2) is applied to the wall velocity motion.

  3. Dynamics of High Sound-Speed Metal Confiners Driven By Non-Ideal High-Explosive Detonation

    DOE PAGES

    Short, Mark; Jackson, Scott I.

    2015-01-23

    . The range of wall velocities where the overlap occurs increases as the ratio of the wall thickness to inner diameter decreases. In conclusion, this is in contrast to ideal high explosives, where the outer wall velocity histories are only similar when the geometric scale factor (in this case a factor of 2) is applied to the wall velocity motion.« less

  4. Development of highly sensitive and selective antibodies for the detection of the explosive pentaerythritol tetranitrate (PETN) by bioisosteric replacement.

    PubMed

    Hesse, Almut; Biyikal, Mustafa; Rurack, Knut; Weller, Michael G

    2016-02-01

    An improved antibody against the explosive pentaerythritol tetranitrate (PETN) was developed. The immunogen was designed by the concept of bioisosteric replacement, which led to an excellent polyclonal antibody with extreme selectivity and immunoassays of very good sensitivity. Compounds such as nitroglycerine, 2,4,6-trinitrotoluene, 1,3,5-trinitrobenzene, hexogen (RDX), 2,4,6-trinitroaniline, 1,3-dinitrobenzene, octogen (HMX), triacetone triperoxide, ammonium nitrate, 2,4,6-trinitrophenol and nitrobenzene were tested for potential cross-reactivity. The detection limit of a competitive enzyme-linked immunosorbent assay was determined to be around 0.5 µg/l. The dynamic range of the assay was found to be between 1 and 1000 µg/l, covering a concentration range of three decades. This work shows the successful application of the bioisosteric concept in immunochemistry by exchange of a nitroester to a carbonate diester. The antiserum might be used for the development of quick tests, biosensors, microtitration plate immunoassays, microarrays and other analytical methods for the highly sensitive detection of PETN, an explosive frequently used by terrorists, exploiting the extreme difficulty of its detection. Copyright © 2015 John Wiley & Sons, Ltd.

  5. A high-porosity limit for the transition from conductive to convective burning in gas-permeable explosives

    SciTech Connect

    Kagan, Leonid; Sivashinsky, Gregory

    2010-02-15

    The experimentally known phenomenon of an abrupt transition from slow conductive to fast convective (penetrative) burning in a confined gas-permeable explosive is discussed. A simple model, involving only the most essential physical ingredients, is formulated and analyzed. In addition to commonly utilized assumptions of the solid-gas thermal equilibrium, validity of Darcy's law, immobility of the solid phase, and one-step Arrhenius kinetics, the model employs the distinguished limit combining high-porosity with high solid/gas density ratio, resulting in conservation of enthalpy, advantageous for theoretical analysis. A good qualitative agreement between theoretical and experimental dependencies is obtained. The transition is triggered by a localized autoignition in the extended resistance-induced preheat zone formed ahead of the advancing deflagration, provided the pressure difference between hot gas products and gases deep inside the pores of the unburned solid exceeds a certain critical level. In line with observations the critical overpressure increases with diminishing permeability. (author)

  6. Measurement of carbon condensation using small-angle x-ray scattering during detonation of the high explosive hexanitrostilbene

    SciTech Connect

    Bagge-Hansen, M.; Lauderbach, L. M.; Hodgin, R.; Bastea, S.; Fried, L.; Jones, A.; van Buuren, T.; Hansen, D.; Benterou, J.; May, C.; Graber, T.; Jensen, B. J.; Ilavsky, J.; Willey, T. M.

    2015-06-24

    The dynamics of carboncondensation in detonating high explosives remains controversial. Detonation model validation requires data for processes occurring at nanometer length scales on time scales ranging from nanoseconds to microseconds. A new detonation endstation has been commissioned to acquire and provide time-resolved small-angle x-ray scattering (SAXS) from detonating explosives. Hexanitrostilbene (HNS) was selected as the first to investigate due to its ease of initiation using exploding foils and flyers, vacuum compatibility, high thermal stability, and stoichiometric carbon abundance that produces high carbon condensate yields. The SAXS data during detonation, collected with 300 ns time resolution, provide unprecedented signal fidelity over a broad q-range. This fidelity permits the first analysis of both the Guinier and Porod/power-law regions of the scattering profile during detonation, which contains information about the size and morphology of the resultant carbon condensate nanoparticles. To bolster confidence in these data, the scattering angle and intensity were additionally cross-referenced with a separate, highly calibrated SAXS beamline. The data show that HNS produces carbon particles with a radius of gyration of 2.7 nm in less than 400 ns after the detonation front has passed, and this size and morphology are constant over the next several microseconds. These data directly contradict previous pioneering work on RDX/TNT mixtures and TATB, where observations indicate significant particle growth (50% or more) continues over several microseconds. As a result, the power-law slope is about –3, which is consistent with a complex disordered, irregular, or folded sp2 sub-arrangement within a relatively monodisperse structure possessing radius of gyration of 2.7 nm after the detonation of HNS.

  7. Measurement of carbon condensates using small-angle x-ray scattering during detonation of the high explosive hexanitrostilbene

    SciTech Connect

    Bagge-Hansen, M.; Lauderbach, L.; Hodgin, R.; Bastea, S.; Fried, L.; Jones, A.; van Buuren, T.; Hansen, D.; Benterou, J.; May, C.; Graber, T.; Jensen, B. J.; Ilavsky, J.; Willey, T. M.

    2015-06-24

    In this study, the dynamics of carbon condensation in detonating high explosives remains controversial. Detonation model validation requires data for processes occurring at nanometer length scales on time scales ranging from nanoseconds to microseconds. A new detonation end station has been commissioned to acquire and provide time-resolved small-angle x-ray scattering (SAXS) from detonating explosives. Hexanitrostilbene (HNS) was selected as the first to investigate due to its ease of initiation using exploding foils and flyers, vacuum compatibility, high thermal stability, and stoichiometric carbon abundance that produces high carbon condensate yields. The SAXS data during detonation, collected with 300 ns time resolution, provide unprecedented signal fidelity over a broad q-range. This fidelity permits the first analysis of both the Guinier and Porod/power-law regions of the scattering profile during detonation, which contains information about the size and morphology of the resultant carbon condensate nanoparticles. To bolster confidence in these data, the scattering angle and intensity were additionally cross-referenced with a separate, highly calibrated SAXS beamline. The data show that HNS produces carbon particles with a radius of gyration of 2.7 nm in less than 400 ns after the detonation front has passed, and this size and morphology are constant over the next several microseconds. These data directly contradict previous pioneering work on RDX/TNT mixtures and TATB, where observations indicate significant particle growth (50% or more) continues over several microseconds. The power-law slope is about -3, which is consistent with a complex disordered, irregular, or folded sp2 sub-arrangement within a relatively monodisperse structure possessing radius of gyration of 2.7 nm after the detonation of HNS.

  8. Measurement of carbon condensates using small-angle x-ray scattering during detonation of the high explosive hexanitrostilbene

    SciTech Connect

    Bagge-Hansen, M.; Lauderbach, L.; Hodgin, R.; Bastea, S.; Fried, L.; Jones, A.; Buuren, T. van; Hansen, D.; Benterou, J.; May, C.; Willey, T. M.; Graber, T.; Jensen, B. J.; Ilavsky, J.

    2015-06-28

    The dynamics of carbon condensation in detonating high explosives remains controversial. Detonation model validation requires data for processes occurring at nanometer length scales on time scales ranging from nanoseconds to microseconds. A new detonation endstation has been commissioned to acquire and provide time-resolved small-angle x-ray scattering (SAXS) from detonating explosives. Hexanitrostilbene (HNS) was selected as the first to investigate due to its ease of initiation using exploding foils and flyers, vacuum compatibility, high thermal stability, and stoichiometric carbon abundance that produces high carbon condensate yields. The SAXS data during detonation, collected with 300 ns time resolution, provide unprecedented signal fidelity over a broad q-range. This fidelity permits the first analysis of both the Guinier and Porod/power-law regions of the scattering profile during detonation, which contains information about the size and morphology of the resultant carbon condensate nanoparticles. To bolster confidence in these data, the scattering angle and intensity were additionally cross-referenced with a separate, highly calibrated SAXS beamline. The data show that HNS produces carbon particles with a radius of gyration of 2.7 nm in less than 400 ns after the detonation front has passed, and this size and morphology are constant over the next several microseconds. These data directly contradict previous pioneering work on RDX/TNT mixtures and TATB, where observations indicate significant particle growth (50% or more) continues over several microseconds. The power-law slope is about −3, which is consistent with a complex disordered, irregular, or folded sp{sup 2} sub-arrangement within a relatively monodisperse structure possessing radius of gyration of 2.7 nm after the detonation of HNS.

  9. Measurement of carbon condensates using small-angle x-ray scattering during detonation of the high explosive hexanitrostilbene

    DOE PAGES

    Bagge-Hansen, M.; Lauderbach, L.; Hodgin, R.; ...

    2015-06-24

    In this study, the dynamics of carbon condensation in detonating high explosives remains controversial. Detonation model validation requires data for processes occurring at nanometer length scales on time scales ranging from nanoseconds to microseconds. A new detonation end station has been commissioned to acquire and provide time-resolved small-angle x-ray scattering (SAXS) from detonating explosives. Hexanitrostilbene (HNS) was selected as the first to investigate due to its ease of initiation using exploding foils and flyers, vacuum compatibility, high thermal stability, and stoichiometric carbon abundance that produces high carbon condensate yields. The SAXS data during detonation, collected with 300 ns time resolution,more » provide unprecedented signal fidelity over a broad q-range. This fidelity permits the first analysis of both the Guinier and Porod/power-law regions of the scattering profile during detonation, which contains information about the size and morphology of the resultant carbon condensate nanoparticles. To bolster confidence in these data, the scattering angle and intensity were additionally cross-referenced with a separate, highly calibrated SAXS beamline. The data show that HNS produces carbon particles with a radius of gyration of 2.7 nm in less than 400 ns after the detonation front has passed, and this size and morphology are constant over the next several microseconds. These data directly contradict previous pioneering work on RDX/TNT mixtures and TATB, where observations indicate significant particle growth (50% or more) continues over several microseconds. The power-law slope is about -3, which is consistent with a complex disordered, irregular, or folded sp2 sub-arrangement within a relatively monodisperse structure possessing radius of gyration of 2.7 nm after the detonation of HNS.« less

  10. Measurement of carbon condensates using small-angle x-ray scattering during detonation of the high explosive hexanitrostilbene

    NASA Astrophysics Data System (ADS)

    Bagge-Hansen, M.; Lauderbach, L.; Hodgin, R.; Bastea, S.; Fried, L.; Jones, A.; van Buuren, T.; Hansen, D.; Benterou, J.; May, C.; Graber, T.; Jensen, B. J.; Ilavsky, J.; Willey, T. M.

    2015-06-01

    The dynamics of carbon condensation in detonating high explosives remains controversial. Detonation model validation requires data for processes occurring at nanometer length scales on time scales ranging from nanoseconds to microseconds. A new detonation endstation has been commissioned to acquire and provide time-resolved small-angle x-ray scattering (SAXS) from detonating explosives. Hexanitrostilbene (HNS) was selected as the first to investigate due to its ease of initiation using exploding foils and flyers, vacuum compatibility, high thermal stability, and stoichiometric carbon abundance that produces high carbon condensate yields. The SAXS data during detonation, collected with 300 ns time resolution, provide unprecedented signal fidelity over a broad q-range. This fidelity permits the first analysis of both the Guinier and Porod/power-law regions of the scattering profile during detonation, which contains information about the size and morphology of the resultant carbon condensate nanoparticles. To bolster confidence in these data, the scattering angle and intensity were additionally cross-referenced with a separate, highly calibrated SAXS beamline. The data show that HNS produces carbon particles with a radius of gyration of 2.7 nm in less than 400 ns after the detonation front has passed, and this size and morphology are constant over the next several microseconds. These data directly contradict previous pioneering work on RDX/TNT mixtures and TATB, where observations indicate significant particle growth (50% or more) continues over several microseconds. The power-law slope is about -3, which is consistent with a complex disordered, irregular, or folded sp2 sub-arrangement within a relatively monodisperse structure possessing radius of gyration of 2.7 nm after the detonation of HNS.

  11. High luminosity, slow ejecta and persistent carbon lines: SN 2009dc challenges thermonuclear explosion scenarios

    NASA Astrophysics Data System (ADS)

    Taubenberger, S.; Benetti, S.; Childress, M.; Pakmor, R.; Hachinger, S.; Mazzali, P. A.; Stanishev, V.; Elias-Rosa, N.; Agnoletto, I.; Bufano, F.; Ergon, M.; Harutyunyan, A.; Inserra, C.; Kankare, E.; Kromer, M.; Navasardyan, H.; Nicolas, J.; Pastorello, A.; Prosperi, E.; Salgado, F.; Sollerman, J.; Stritzinger, M.; Turatto, M.; Valenti, S.; Hillebrandt, W.

    2011-04-01

    Extended optical and near-IR observations reveal that SN 2009dc shares a number of similarities with normal Type Ia supernovae (SNe Ia), but is clearly overluminous, with a (pseudo-bolometric) peak luminosity of log (L) = 43.47 (erg s-1). Its light curves decline slowly over half a year after maximum light [Δm15(B)true= 0.71], and the early-time near-IR light curves show secondary maxima, although the minima between the first and the second peaks are not very pronounced. The bluer bands exhibit an enhanced fading after ˜200 d, which might be caused by dust formation or an unexpectedly early IR catastrophe. The spectra of SN 2009dc are dominated by intermediate-mass elements and unburned material at early times, and by iron-group elements at late phases. Strong C II lines are present until ˜2 weeks past maximum, which is unprecedented in thermonuclear SNe. The ejecta velocities are significantly lower than in normal and even subluminous SNe Ia. No signatures of interaction with a circumstellar medium (CSM) are found in the spectra. Assuming that the light curves are powered by radioactive decay, analytic modelling suggests that SN 2009dc produced ˜1.8 M⊙ of 56Ni assuming the smallest possible rise time of 22 d. Together with a derived total ejecta mass of ˜2.8 M⊙, this confirms that SN 2009dc is a member of the class of possible super-Chandrasekhar-mass SNe Ia similar to SNe 2003fg, 2006gz and 2007if. A study of the hosts of SN 2009dc and other superluminous SNe Ia reveals a tendency of these SNe to explode in low-mass galaxies. A low metallicity of the progenitor may therefore be an important prerequisite for producing superluminous SNe Ia. We discuss a number of possible explosion scenarios, ranging from super-Chandrasekhar-mass white-dwarf progenitors over dynamical white-dwarf mergers and Type I? SNe to a core-collapse origin of the explosion. None of the models seems capable of explaining all properties of SN 2009dc, so that the true nature of this SN

  12. Phenomenon of Energy Focusing in Explosive Systems which include High Modulus Elastic Elements

    NASA Astrophysics Data System (ADS)

    Balagansky, I.; Hokamoto, K.; Manikandan, P.; Matrosov, A.; Stadnichenko, I.; Miyoshi, H.

    2009-06-01

    The phenomenon was observed in a passive HE charge of cast Comp. B without cumulative shape under shock wave loading by explosion of an active HE charge through water after preliminary compression by a leading wave in silicon carbide insert. The phenomenon manifested itself as a hole in identification steel specimen with depth of about 10 mm and diameter of about 5 mm. Results of experiments on studying of conditions of implementation of this phenomenon for SEP and Comp. B are presented. For each HE a number of experiments has been executed at various length of silicon carbide insert. Presence or absence of a hole in the steel specimen was determined. Also a number of optical registrations of process in framing mode with record step of 1 μs have been executed. Digital video camera SHIMADZU HPV-1 was used for optical registration. Results of experiments testify that the phenomenon is reproduced both for SEP, and for Comp. B. Focusing process is observed in conditions close to critical conditions of transfer of a detonation from active to a passive HE charge.

  13. Equation of state formulation for unreacted solid high explosives, PETN and HMX

    NASA Astrophysics Data System (ADS)

    Nagayama, Kunihito

    2015-06-01

    Equation of state (EOS) for unreacted explosives has been formulated thermodynamically aiming at using with numerical code of SDT processes. A generalized form of EOS is given in terms of p-v-E from the available static isothermal compression curve with non-constant specific heat, and arbitrary Grüneisen volume function. In this paper, a procedure of providing p-v-E EOS is developed based on the specific heat at constant volume as a function of entropy, Grüneisen volume function, together with Birch-Murnagan form of the isotherm. Material function of EOS and shock Hugoniot for PETN and HMX has been calculated, which is compared with the experimental data of shock-particle velocity Hugoniot. Dependence of shock pressure and temperature on the Grüneisen volume function is discussed. Insensitivity of the shock-particle velocity relationship to functional form of Grüneisen volume function is also shown. Second author: Dr. Shiro Kubota (AIST Japan).

  14. High power laser coupling to carbon nano-tubes and ion Coulomb explosion

    SciTech Connect

    K, Magesh Kumar K; Tripathi, V. K.

    2013-09-15

    Linear and non linear interaction of laser with an array of carbon nanotubes is investigated. The ac conductivity of nanotubes, due to uneven response of free electrons in them to axial and transverse fields, is a tensor. The propagation constant for p-polarization shows resonance at a specific frequency that varies with the direction of laser propagation. It also shows surface plasmon resonance at ω=ω{sub p}/√(2), where ω{sub p} is the plasma frequency of free electrons inside a nanotube, assumed to be uniform plasma cylinder. The attenuation constant is also resonantly enhanced around these frequencies. At large laser amplitude, the nanotubes behave as thin plasma rods. As the electrons get heated, the nanotubes undergo hydrodynamic expansion. At an instant when plasma frequency reaches ω{sub p}=√(2)ω, the electron temperature rises rapidly and then saturates. For a Gaussian laser beam, the heating rate is maximum on the laser axis and falls off with the distance r from the axis. When the excursion of the electrons Δ is comparable or larger than the radius of the nanotube r{sub c}, the nanotubes undergo ion Coulomb explosion. The distribution function of ions turns out to be a monotonically decreasing function of energy.

  15. High-explosive properties from classical molecular dynamics simulations and quantum-chemical computations

    SciTech Connect

    Sewell, T. D.; Gan, C. K.; Jaramillo, E.; Strachan, A. H.

    2004-01-01

    We are using classical molecular dynamics and condensed phase electronic-structure methods to predict some of the thermophysical and mechanical properties that are needed as input to realistic mesoscale models for plastic-bonded explosives. The main materials studied to date are HMX, PETN, Estane copolymer, and bi(2,2-dinitropropyl) formal/acetal (BDNPF/A). Emphasis is placed on non-reactive properties and thermodynamic states relevant to cookoff and shock initiation phenomena. Both crystal and liquid-state properties are of interest. Typical simulation sizes and times are {approx}10{sup 2} molecules and 2-10 ns, respectively. The overarching goal is to develop internally consistent model thermodynamic and elastic mechanical descriptions for the materials. Prioritization among the set of properties amenable to atomistic simulation is made based on ongoing interactions with mesoscale modelers at Los Alamos and elsewhere. Recent work will be summarized and our view of profitable directions for future research will be discussed, including preliminary results for large-scale molecular dynamics simulations of shock response of crystalline HMX.

  16. Tin particle size measurements in high explosively driven shockwave experiments using Mie scattering method

    NASA Astrophysics Data System (ADS)

    Monfared, Shabnam; Buttler, William; Schauer, Martin; Lalone, Brandon; Pack, Cora; Stevens, Gerald; Stone, Joseph; Special Technologies Laboratory Collaboration; Los Alamos National Laboratory Team

    2014-03-01

    Los Alamos National Laboratory is actively engaged in the study of material failure physics to support the hydrodynamic models development, where an important failure mechanism of explosively shocked metals causes mass ejection from the backside of a shocked surface with surface perturbations. Ejecta models are in development for this situation. Our past work has clearly shown that the total ejected mass and mass-velocity distribution sensitively link to the wavelength and amplitude of these perturbations. While we have had success developing ejecta mass and mass-velocity models, we need to better understand the size and size-velocity distributions of the ejected mass. To support size measurements we have developed a dynamic Mie scattering diagnostic based on a CW laser that permits measurement of the forward attenuation cross-section combined with a dynamic mass-density and mass-velocity distribution, as well as a measurement of the forward scattering cross-section at 12 angles (5- 32.5 degrees) in increments of 2.5 degrees. We compare size distribution followed from Beers law with attenuation cross-section and mass measurement to the dynamic size distribution determined from scattering cross-section alone. We report results from our first quality experiments.

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

    PubMed

    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.

  18. Biological Denitrification of High Nitrate Processing Wastewaters from Explosives Production Plant.

    PubMed

    Cyplik, Paweł; Marecik, Roman; Piotrowska-Cyplik, Agnieszka; Olejnik, Anna; Drożdżyńska, Agnieszka; Chrzanowski, Lukasz

    2012-05-01

    Wastewater samples originating from an explosives production plant (3,000 mg N l(-1) nitrate, 4.8 mg l(-1) nitroglycerin, 1.9 mg l(-1) nitroglycol and 1,200 mg l(-1) chemical oxygen demand) were subjected to biological purification. An attempt to completely remove nitrate and to decrease the chemical oxygen demand was carried out under anaerobic conditions. A soil isolated microbial consortium capable of biodegrading various organic compounds and reduce nitrate to atmospheric nitrogen under anaerobic conditions was used. Complete removal of nitrates with simultaneous elimination of nitroglycerin and ethylene glycol dinitrate (nitroglycol) was achieved as a result of the conducted research. Specific nitrate reduction rate was estimated at 12.3 mg N g(-1) VSS h(-1). Toxicity of wastewater samples during the denitrification process was studied by measuring the activity of dehydrogenases in the activated sludge. Mutagenicity was determined by employing the Ames test. The maximum mutagenic activity did not exceed 0.5. The obtained results suggest that the studied wastewater samples did not exhibit mutagenic properties.

  19. Explosively developing extratropical cyclone associated with the high wind-waves along the east coast of Korea

    NASA Astrophysics Data System (ADS)

    Heo, Ki-Young; Choi, Jin-Yong; Park, Kwang-Soon

    2017-04-01

    An extreme extratropical cyclone struck the northern part of Korea on May 3, 2016 causing significant damage to property on the land due to extreme winds and abnormal high waves in coastal area. The meteorological composite fields for the cyclone show a strong surface wind velocity (up to 45 m s-1) during its mature phase. This study investigated the development mechanisms of an explosive cyclone through numerical simulation and sensitivity experiments using the Advanced Research version of the Weather Research and Forecasting (WRF-ARW) model. The trigger mechanism for the explosive cyclogenesis is the strong baroclinic instability and temperature advection associated with upper-level cut-off low and the interaction of potential vorticity (PV) anomalies between the lower- and upper-level. The efficient placement of the high- and low-level jets forms a favorable condition for its development and transportation of water vapor and the instability energy into the cyclone. The sea-state wave simulation of large swell waves along the eastern coast of the Korean Peninsula is obtained using the wave model WAVEWATCHIII (WW3) forced by the 10-m above ground level wind field from the WRF-ARW simulations. The simulation results of WW3 for the significant wave height were compared against buoy observation data at 1-h intervals. The simulated significant wave height systematically underestimated by 0.5 m. However, strong wind field generated by the cyclone is clarified as key features determining the characteristics of the high waves in terms of the temporal growth and decay patterns.

  20. [Peculiarities of forensic medical reconstruction of the mechanism of injuries in numerous victims of the explosion of a high-capacity blasting device].

    PubMed

    Fradkina, N A; Kovalev, A V; Makarov, I Iu

    2013-01-01

    The systemic analysis of forensic medical practice in Moscow during the past 15 years has demonstrated the scientific, practical, and social significance of expertise of peace-time blast injuries resulting from many terrorist attacks with the use of improvised high-capacity explosive devices that caused multiple human victims. The authors emphasize the current lack of objective forensic medical criteria for the reconstruction of the mechanism of injuries in numerous victims of the explosion of a high-capacity blasting device. It dictates the necessity of their development and substantiation of their practical application.

  1. Report on the suitability of Class 6, U.S. government security repositories for the storage of small quantities of high explosives

    SciTech Connect

    Harry, H.H.; Murk, D.

    1998-03-01

    The Explosives Review Committee initiated a study into the safety aspects of the common practice of storing small amounts (< 10 grams per drawer) of high explosives in safes. Although storage of HE in older asbestos lined safes was permitted, the newer style Class 6 Security safes are an unacceptable repository for even very small amounts of HE without the use of a blast mitigating insert. The authors have developed a drawer liner in the form of a laminated Lexan, foam, plywood box that will withstand the blast and contain the fragments from up to 10 grams of high explosives. This liner will fit into the drawer of any existing safe. The liner will provide blast and fragment protection, and the safe will provide security protection. This report describes the testing of modern safes and the performance of the liner insert.

  2. Heat pipe cooling system of high-power three-level explosion-proof inverter based on the loss calculation and finite element analysis

    NASA Astrophysics Data System (ADS)

    Li, Yuan

    2017-07-01

    The special using condition of high-power three-level explosion-proof inverter limits its cooling system within heat pipe and water-cooled cooling systems. How to calculate these two systems quantitatively to provide references for engineering application becomes one of the critical problems. In this paper, the principle of three-level explosion-proof was introduced first, and the power-loss generation theory was described and deduced into equations. Secondly, the heat pipe cooling system theory calculation was conducted based on the power losses of power devices, and the whole cooling system model was built by using finite element analysis. Finally, the temperature rise experiment was carried out on a 1 MW high-power three-level explosion-proof inverter, and the results proved the feasibility of this theory and its accuracy of analysis.

  3. A Comparison of Neutron-Based Non-Destructive Assessment Methods for Chemical Warfare Materiel and High Explosives

    SciTech Connect

    E.H. Seabury; D.L. Chichester; C.J. Wharton; A.J. Caffrey

    2008-08-01

    Prompt Gamma Neutron Activation Analysis (PGNAA) systems employ neutrons as a probe to interrogate items, e.g. chemical warfare materiel-filled munitions. The choice of a neutron source in field-portable systems is determined by its ability to excite nuclei of interest, operational concerns such as radiological safety and ease-of-use, and cost. Idaho National Laboratory’s PINS Chemical Assay System has traditionally used a Cf-252 isotopic neutron source, but recently a Deuterium-Tritium (DT) Electronic Neutron Generator (ENG) has been tested as an alternate neutron source. This paper presents the results of using both of these neutron sources to interrogate chemical warfare materiel (CWM) and high explosive (HE) filled munitions.

  4. A Comparison of Neutron-Based Non-Destructive Assessment Methods for Chemical Warfare Materiel and High Explosives

    NASA Astrophysics Data System (ADS)

    Seabury, E. H.; Chichester, D. L.; Wharton, C. J.; Caffrey, A. J.

    2009-03-01

    Prompt Gamma Neutron Activation Analysis (PGNAA) systems employ neutrons as a probe to interrogate items, e.g. chemical warfare materiel-filled munitions. The choice of a neutron source in field-portable systems is determined by its ability to excite nuclei of interest, operational concerns such as radiological safety and ease-of-use, and cost. Idaho National Laboratory's PINS Chemical Assay System has traditionally used a 252Cf isotopic neutron source, but recently a deuterium-tritium (DT) electronic neutron generator (ENG) has been tested as an alternate neutron source. This paper presents the results of using both of these neutron sources to interrogate chemical warfare materiel (CWM) and high explosive (HE) filled munitions.

  5. Determination of the radiation resistance order of high explosives by the two dimensional correlation X-ray photoelectron spectroscopy

    NASA Astrophysics Data System (ADS)

    Sui, Heliang; Hao, Xiaofei; Luo, Yiwei; Xu, Jinjiang; Zhong, Fachun; Xu, Ruijuan

    2017-09-01

    Two-dimensional X-ray photoelectron spectroscopy (2DXPS) was employed to obtain the radiation resistance order of high explosives. Mixed hexanitrohexaazaisowurtzitane (CL-20) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) were irradiated by X-ray radiation. The time-dependent N1s XPS spectra were collected. 2DXPS was used to analyze the variation of the binding energy peaks. The main degradation time of TATB was longer than that of CL-20. CL-20 changes occurred prior to that of TATB during radiation. These changes suggest that TATB exhibited higher radiation resistance property than CL-20. 2DXPS is a very useful method to distinguish the radiation resistance orders of materials.

  6. A Comparison of Neutron-Based Non-Destructive Assessment Methods for Chemical Warfare Material and High Explosives

    SciTech Connect

    Seabury, E. H.; Chichester, D. L.; Wharton, C. J.; Caffrey, A. J.

    2009-03-10

    Prompt Gamma Neutron Activation Analysis (PGNAA) systems employ neutrons as a probe to interrogate items, e.g. chemical warfare materiel-filled munitions. The choice of a neutron source in field-portable systems is determined by its ability to excite nuclei of interest, operational concerns such as radiological safety and ease-of-use, and cost. Idaho National Laboratory's PINS Chemical Assay System has traditionally used a {sup 252}Cf isotopic neutron source, but recently a deuterium-tritium (DT) electronic neutron generator (ENG) has been tested as an alternate neutron source. This paper presents the results of using both of these neutron sources to interrogate chemical warfare materiel (CWM) and high explosive (HE) filled munitions.

  7. Closure plan for the decommissioned high explosives rinse-water lagoons at Lawrence Livermore National Laboratory Site 300

    SciTech Connect

    Carpenter, D.W.; Lamarre, A.L.; Crow, N.B.; Swearengen, P.M.

    1988-05-31

    The High Explosives (HE) Process Area is a major facility at Lawrence Livermore National Laboratory (LLNL) Site 300. Within the Process Area, rinse water from various buildings formerly was discharged to nine relatively small, unlined lagoons where it was disposed of by evaporation and infiltration. In 1985, LLNL decommissioned these lagoons and diverted the rinse waters to two doubly lined surface impoundments. LLNL conducted the hydrogeologic investigations required to support the permanent closure of the none decommissioned lagoons. These studies included drilling ground water monitoring wells and extensively collecting soil and rock samples, which were analyzed for EPA toxic metals, HE compounds, and purgeable and extractable priority organic pollutants. On October 26, 1987, the RWQCB requested that we prepare a comprehensive report to summarize and discuss the findings of the LLNL HE Process Area Investigation. This report is our response to the Board's request. 22 refs., 19 figs. , 45 tabs.

  8. Abiotic transformation of high explosives by freshly precipitated iron minerals in aqueous Fe¹¹ solutions

    SciTech Connect

    Boparai, Hardiljeet K.; Comfort, Steve; Satapanajaru, Tunlawit; Szecsody, James E.; Grossl, Paul; Shea, Patrick

    2010-05-11

    Zerovalent iron barriers have become a viable treatment for field-scale cleanup of various ground water contaminants. While contact with the iron surface is important for contaminant destruction, the interstitial pore water within and near the iron barrier will be laden with aqueous, adsorbed and precipitated FeII phases. These freshly precipitated iron minerals could play an important role in transforming high explosives (HE). Our objective was to determine the transformation of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), and TNT (2,4,6-trinitrotoluene) by freshly precipitated iron FeII/FeIII minerals. This was accomplished by quantifying the effects of initial FeII concentration, pH, and the presence of aquifer solids (FeIII phases) on HE transformation rates. Results showed that at pH 8.2, freshly precipitated iron minerals transformed RDX, HMX, and TNT with reaction rates increasing with increasing FeII concentrations. RDX and HMX transformations in these solutions also increased with increasing pH (5.8-8.55). By contrast, TNT transformation was not influenced by pH (6.85-8.55) except at pH values <6.35. Transformations observed via LC/MS included a variety of nitroso products (RDX, HMX) and amino degradation products (TNT). XRD analysis identified green rust and magnetite as the dominant iron solid phases that precipitated from the aqueous FeII during HE treatment under anaerobic conditions. Geochemical modeling also predicted FeII activity would likely be controlled by green rust and magnetite. These results illustrate the important role freshly precipitated FeII/FeIII minerals in aqueous FeII solutions play in the transformation of high explosives.

  9. Avian community composition in response to high explosive testing operations at Los Alamos National Laboratory in Northern New Mexico

    DOE PAGES

    Keller, David C.; Fresquez, Philip R.; Hansen, Leslie A.; ...

    2015-12-28

    Breeding bird abundance, species richness, evenness, diversity, composition, productivity, and survivorship were determined near a high-explosive detonation site at Los Alamos National Laboratory, New Mexico, USA, during pre-operation (1997-1999) and operation (2000-2014) periods. The operation periods consisted of detonations (<23 kg in yield and <3 per breeding season) in open air (2000-2002), within foam containment (2003-2006) and within steel vessel containment (2007-2014) systems; the latter two were employed to reduce noise and dispersal of high-explosives residues. A total of 2952 bird captures, representing 80 species, was recorded during 18 years of mist net operations using the Monitoring Avian Productivity andmore » Survivorship protocol. Individuals captured were identified to species, aged, sexed, and banded during May through August of each year. There were no significant differences (p > 0.05) in mean avian abundance and species evenness in any of the operation periods as compared with the pre-operation period. Species richness and diversity were significantly higher (p < 0.05) during the vessel containment period (2007-2014) than the pre-operation period. The time period of this study coincided with a wildfire (2000), a bark beetle infestation (2002), and two periods of drought (Nov 1999-Mar 2004 and Dec 2005-Dec 2014) that affected the study area. Furthermore, analysis of aerial photos determined that the average percent canopy cover of mature ponderosa pines (Pinus ponderosa) within 100 feet of mist net sites declined from 12% to 3% between 1991 and 2014 and the percent cover of shrubs slightly increased.« less

  10. Environmental Assessment for the High Explosives Wastewater Treatment Facility, Los Alamos National Laboratory, Los Alamos, New Mexico

    SciTech Connect

    1995-08-03

    The Department of Energy (DOE) has identified a need to improve the management of wastewater resulting from high explosives (HE) research and development work at Los Alamos National Laboratory (LANL). LANL`s current methods off managing HE-contaminated wastewater cannot ensure that discharged HE wastewater would consistently meet the Environmental Protection Agency`s (EPA`s) standards for wastewater discharge. The DOE needs to enhance He wastewater management to e able to meet both present and future regulatory standards for wastewater discharge. The DOE also proposes to incorporate major pollution prevention and waste reduction features into LANL`s existing HE production facilities. Currently, wastewater from HE processing buildings at four Technical Areas (TAs) accumulates in sumps where particulate HE settles out and barium is precipitated. Wastewater is then released from the sumps to the environment at 15 permitted outfalls without treatment. The released water may contain suspended and dissolved contaminants, such as HE and solvents. This Environmental Assessment (EA) analyzes two alternatives, the Proposed Action and the Alternative Action, that would meet the purpose and need for agency action. Both alternatives would treat all HE process wastewater using sand filters to remove HE particulates and activated carbon to adsorb organic solvents and dissolved HE. Under either alternative, LANL would burn solvents and flash dried HE particulates and spent carbon following well-established procedures. Burning would produce secondary waste that would be stored, treated, and disposed of at TA-54, Area J. This report contains the Environmental Assessment, as well as the Finding of No Significant Impact and Floodplain Statement of Findings for the High Explosives Wastewater Treatment Facility.

  11. Avian community composition in response to high explosive testing operations at Los Alamos National Laboratory in Northern New Mexico

    SciTech Connect

    Keller, David C.; Fresquez, Philip R.; Hansen, Leslie A.; Kaschube, Danielle R.

    2015-12-28

    Breeding bird abundance, species richness, evenness, diversity, composition, productivity, and survivorship were determined near a high-explosive detonation site at Los Alamos National Laboratory, New Mexico, USA, during pre-operation (1997-1999) and operation (2000-2014) periods. The operation periods consisted of detonations (<23 kg in yield and <3 per breeding season) in open air (2000-2002), within foam containment (2003-2006) and within steel vessel containment (2007-2014) systems; the latter two were employed to reduce noise and dispersal of high-explosives residues. A total of 2952 bird captures, representing 80 species, was recorded during 18 years of mist net operations using the Monitoring Avian Productivity and Survivorship protocol. Individuals captured were identified to species, aged, sexed, and banded during May through August of each year. There were no significant differences (p > 0.05) in mean avian abundance and species evenness in any of the operation periods as compared with the pre-operation period. Species richness and diversity were significantly higher (p < 0.05) during the vessel containment period (2007-2014) than the pre-operation period. The time period of this study coincided with a wildfire (2000), a bark beetle infestation (2002), and two periods of drought (Nov 1999-Mar 2004 and Dec 2005-Dec 2014) that affected the study area. Furthermore, analysis of aerial photos determined that the average percent canopy cover of mature ponderosa pines (Pinus ponderosa) within 100 feet of mist net sites declined from 12% to 3% between 1991 and 2014 and the percent cover of shrubs slightly increased.

  12. TOWARD END-TO-END MODELING FOR NUCLEAR EXPLOSION MONITORING: SIMULATION OF UNDERGROUND NUCLEAR EXPLOSIONS AND EARTHQUAKES USING HYDRODYNAMIC AND ANELASTIC SIMULATIONS, HIGH-PERFORMANCE COMPUTING AND THREE-DIMENSIONAL EARTH MODELS

    SciTech Connect

    Rodgers, A; Vorobiev, O; Petersson, A; Sjogreen, B

    2009-07-06

    This paper describes new research being performed to improve understanding of seismic waves generated by underground nuclear explosions (UNE) by using full waveform simulation, high-performance computing and three-dimensional (3D) earth models. The goal of this effort is to develop an end-to-end modeling capability to cover the range of wave propagation required for nuclear explosion monitoring (NEM) from the buried nuclear device to the seismic sensor. The goal of this work is to improve understanding of the physical basis and prediction capabilities of seismic observables for NEM including source and path-propagation effects. We are pursuing research along three main thrusts. Firstly, we are modeling the non-linear hydrodynamic response of geologic materials to underground explosions in order to better understand how source emplacement conditions impact the seismic waves that emerge from the source region and are ultimately observed hundreds or thousands of kilometers away. Empirical evidence shows that the amplitudes and frequency content of seismic waves at all distances are strongly impacted by the physical properties of the source region (e.g. density, strength, porosity). To model the near-source shock-wave motions of an UNE, we use GEODYN, an Eulerian Godunov (finite volume) code incorporating thermodynamically consistent non-linear constitutive relations, including cavity formation, yielding, porous compaction, tensile failure, bulking and damage. In order to propagate motions to seismic distances we are developing a one-way coupling method to pass motions to WPP (a Cartesian anelastic finite difference code). Preliminary investigations of UNE's in canonical materials (granite, tuff and alluvium) confirm that emplacement conditions have a strong effect on seismic amplitudes and the generation of shear waves. Specifically, we find that motions from an explosion in high-strength, low-porosity granite have high compressional wave amplitudes and weak shear

  13. Visualization of explosion phenomena using a high-speed video camera with an uncoupled objective lens by fiber-optic

    NASA Astrophysics Data System (ADS)

    Tokuoka, Nobuyuki; Miyoshi, Hitoshi; Kusano, Hideaki; Hata, Hidehiro; Hiroe, Tetsuyuki; Fujiwara, Kazuhito; Yasushi, Kondo

    2008-11-01

    Visualization of explosion phenomena is very important and essential to evaluate the performance of explosive effects. The phenomena, however, generate blast waves and fragments from cases. We must protect our visualizing equipment from any form of impact. In the tests described here, the front lens was separated from the camera head by means of a fiber-optic cable in order to be able to use the camera, a Shimadzu Hypervision HPV-1, for tests in severe blast environment, including the filming of explosions. It was possible to obtain clear images of the explosion that were not inferior to the images taken by the camera with the lens directly coupled to the camera head. It could be confirmed that this system is very useful for the visualization of dangerous events, e.g., at an explosion site, and for visualizations at angles that would be unachievable under normal circumstances.

  14. Explosion containment device

    DOEpatents

    Benedick, William B.; Daniel, Charles J.

    1977-01-01

    The disclosure relates to an explosives storage container for absorbing and containing the blast, fragments and detonation products from a possible detonation of a contained explosive. The container comprises a layer of distended material having sufficient thickness to convert a portion of the kinetic energy of the explosion into thermal energy therein. A continuous wall of steel sufficiently thick to absorb most of the remaining kinetic energy by stretching and expanding, thereby reducing the momentum of detonation products and high velocity fragments, surrounds the layer of distended material. A crushable layer surrounds the continuous steel wall and accommodates the stretching and expanding thereof, transmitting a moderate load to the outer enclosure. These layers reduce the forces of the explosion and the momentum of the products thereof to zero. The outer enclosure comprises a continuous pressure wall enclosing all of the layers. In one embodiment, detonation of the contained explosive causes the outer enclosure to expand which indicates to a visual observer that a detonation has occurred.

  15. The Interaction of Explosively Generated Plasma with Explosives

    NASA Astrophysics Data System (ADS)

    Tasker, Douglas; LANL Team

    2015-06-01

    It has been shown that the temperature of explosively generated plasma (EGP) is of the order of 1 eV and plasma ejecta can be focused to achieve velocities as high as 25 km/s. These high velocity plasma can readily penetrate a wide range of materials including metals. Proof-of-principle tests were performed to determine if EGP could be used for explosive ordnance demolition and other applications. The test goals were: to benignly disable ordnance containing relatively sensitive high performance explosives (PBX-9501); and to investigate the possibility of interrupting an ongoing detonation in a powerful high explosive (again PBX-9501) with EGP. Experiments were performed to establish the optimum sizes of plasma generators for the benign deactivation of high explosives, i.e., the destruction of the ordnance without initiating a detonation or comparable violent event. These experiments were followed by attempts to interrupt an ongoing detonation by the destruction of the unreacted explosive in its path. The results were encouraging. First, it was demonstrated that high explosives could be destroyed without the initiation of a detonation or high order reaction. Second, ongoing detonations were successfully interrupted with EGP. LA-UR-15-20612.

  16. The interaction of explosively generated plasma with explosives

    NASA Astrophysics Data System (ADS)

    Tasker, Douglas G.; Whitley, Von H.; Johnson, Carl E.

    2017-01-01

    It has been shown that the temperature of explosively generated plasma (EGP) is of the order of 1 eV and plasma ejecta can be focused to achieve velocities as high as 25 km/s. Proof-of-principle tests were performed to determine if EGP could be used for explosive ordnance demolition and other applications. The goals were: to benignly disable ordnance containing relatively sensitive high performance explosives (PBX-9501); and to investigate the possibility of interrupting an ongoing detonation in a powerful high explosive (again PBX-9501) with EGP. Experiments were performed to establish the optimum sizes of plasma generators for the benign deactivation of high explosives, i.e., the destruction of the ordnance without initiating a detonation or comparable violent event. These experiments were followed by attempts to interrupt an ongoing detonation by the benign disruption of the unreacted explosive in its path. The results were encouraging. First, it was demonstrated that high explosives could be destroyed without the initiation of a detonation or high order reaction. Second, ongoing detonations were successfully interrupted with EGP. [LA-UR-15-25350

  17. Demonstration Explosion

    NASA Astrophysics Data System (ADS)

    Lee, Charles "Skip"

    1998-05-01

    Last week I did a demonstration that produced a serious explosion. After putting methanol in a big glass carboy and rotating the carboy to build up some methanol vapor, I lit the mouth of the carboy. What normally happens is a "jet engine" effect out of the mouth of the carboy. In my case, the carboy exploded. Two polycarbonate blast shields were shattered and glass was blown as far as 15 feet away. I was not seriously cut and bruised, but had I not been using the two blast shields, I would have been severely injured. At this time, I am not sure what caused the explosion. I have done this demonstration around one hundred times with no problem using the exact same amount of methanol and technique. I think it is important to get the word out that this demonstration may be more dangerous than previously thought. I would also welcome any hypotheses concerning what caused the carboy to explode.

  18. Explosive Joining

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Laurence J. Bement of Langley Research Center invented a technique to permit metal joining operations under hazardous or inaccessible conditions. The process, which provides a joint with double the strength of the parent metal, involves the use of very small quantities of ribbon explosive to create hermetically sealed joints. When the metal plates are slammed together by the explosion's force, joining is accomplished. The collision causes a skin deep melt and ejection of oxide films on the surfaces, allowing a linkup of electrons that produce superstrong, uniform joints. The technique can be used to join metals that otherwise would not join and offers advantages over mechanical fasteners and adhesives. With Langley assistance, Demex International Ltd. refined and commercialized the technology. Applications include plugging leaking tubes in feedwater heaters. Demex produces the small plugs, associated sleeves and detonators. The technology allows faster plugging, reduces downtime, cuts plugging costs and increases reliability.

  19. Method for fabricating non-detonable explosive simulants

    SciTech Connect

    Simpson, Randall L.; Pruneda, Cesar O.

    1995-01-01

    A simulator which is chemically equivalent to an explosive, but is not detonable. The simulator has particular use in the training of explosives detecting dogs and calibrating sensitive analytical instruments. The explosive simulants may be fabricated by different techniques, a first involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and the second involves coating inert beads with thin layers of explosive molecules.

  20. Method for fabricating non-detonable explosive simulants

    SciTech Connect

    Simpson, R.L.; Pruneda, C.O.

    1995-05-09

    A simulator is disclosed which is chemically equivalent to an explosive, but is not detonable. The simulator has particular use in the training of explosives detecting dogs and calibrating sensitive analytical instruments. The explosive simulants may be fabricated by different techniques, a first involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and the second involves coating inert beads with thin layers of explosive molecules. 5 figs.

  1. Method for fabricating non-detonable explosive simulants

    DOEpatents

    Simpson, R.L.; Pruneda, C.O.

    1995-05-09

    A simulator is disclosed which is chemically equivalent to an explosive, but is not detonable. The simulator has particular use in the training of explosives detecting dogs and calibrating sensitive analytical instruments. The explosive simulants may be fabricated by different techniques, a first involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and the second involves coating inert beads with thin layers of explosive molecules. 5 figs.

  2. The application of the high-speed photography in the experiments of boiling liquid expanding vapor explosions

    NASA Astrophysics Data System (ADS)

    Chen, Sining; Sun, Jinhua; Chen, Dongliang

    2007-01-01

    The liquefied-petroleum gas tank in some failure situations may release its contents, and then a series of hazards with different degrees of severity may occur. The most dangerous accident is the boiling liquid expanding vapor explosion (BLEVE). In this paper, a small-scale experiment was established to experimentally investigate the possible processes that could lead to a BLEVE. As there is some danger in using LPG in the experiments, water was used as the test fluid. The change of pressure and temperature was measured during the experiment. The ejection of the vapor and the sequent two-phase flow were recorded by a high-speed video camera. It was observed that two pressure peaks result after the pressure is released. The vapor was first ejected at a high speed; there was a sudden pressure drop which made the liquid superheated. The superheated liquid then boiled violently causing the liquid contents to swell, and also, the vapor pressure in the tank increased rapidly. The second pressure peak was possibly due to the swell of this two-phase flow which was likely to violently impact the wall of the tank with high speed. The whole evolution of the two-phase flow was recorded through photos captured by the high-speed video camera, and the "two step" BLEVE process was confirmed.

  3. Trace Explosive Detection Using Nanosensors

    SciTech Connect

    Senesac, Larry R; Thundat, Thomas George

    2008-01-01

    Selective and sensitive detection of explosives is very important in countering terrorist threats. Detecting trace explosives has become a very complex and expensive endeavor because of a number of factors, such as the wide variety of materials that can be used as explosives, the lack of easily detectable signatures, the vast number of avenues by which these weapons can be deployed, and the lack of inexpensive sensors with high sensitivity and selectivity. High sensitivity and selectivity, combined with the ability to lower the deployment cost of sensors using mass production, is essential in winning the war on explosives-based terrorism. Nanosensors have the potential to satisfy all the requirements for an effective platform for the trace detection of explosives.

  4. New insights into the explosive history of the Yellowstone super-volcano from high-precision dating and mineral chemistry

    NASA Astrophysics Data System (ADS)

    Ellis, B. S.; Mark, D. F.; Nix, C.; Rowe, M. C.; Wolff, J. A.; Kent, A. J.; Loewen, M. W.

    2012-12-01

    Yellowstone is commonly held up as the archetypal 'super-volcano', having had three major eruptive episodes at ~ 2 Ma, 1.3 Ma, and 0.6 Ma. However, given the importance of such large magnitude events on all scales from local to global, this idea has been held up to surprisingly little rigorous testing. Here we combine new high-precision Ar/Ar geochronology and mineral chemistry from multiple phases to shed new light on the explosive history of the Huckleberry Ridge and Lava Creek eruptions from the Yellowstone volcanic field. Recent high precision 40Ar/39Ar geochronology has shown that member C of the Huckleberry Ridge Tuff was erupted at least 6,000 years later than members A and B. This result is supported by significant differences in the compositions of fayalitic olivine, augite, and quartz between the different members. Mafic minerals are compositionally homogeneous with augites and fayalites of member C less magnesian than those found in members A and B. Quartz grains show a variety of textures in CL imaging and have within-grain variations in titanium (determined via EMPA and LA-ICPMS) reaching a factor of 2. Again, member C of the Huckleberry Ridge Tuff has distinct compositions of quartz (with higher Ti up to 242 ppm) than earlier erupted HRT. Quartz from Lava Creek Tuff shows differences in abundance of Ti between members A and B with member A having generally lower Ti (average 55 ppm) than member B (average 102 ppm). The mineral-scale chemistry presented here agrees with the pre-existing field evidence, radiogenic isotopic variation and high-precision geochronology to indicate that member C of Huckleberry Ridge Tuff represents a different magma to that which erupted and formed members A and B. Combining high-precision geochronology and detailed mineral-scale geochemistry from a number of different phases provides a robust method of distinguishing individual magma batches and clarifying the explosive history of a volcano. Our new data suggest that in some

  5. Luminescent metal-organic framework-functionalized graphene oxide nanocomposites and the reversible detection of high explosives

    NASA Astrophysics Data System (ADS)

    Lee, Ji Ha; Jaworski, Justyn; Jung, Jong Hwa

    2013-08-01

    Achieving both high specificity and sensitivity are essential for gas phase chemical detection systems. Recent implementation of Metal-Organic Frameworks (MOFs) have shown great success in separation and storage systems for specific gas molecules. By implementing a MOF structure comprised of Zn2+ coordinated trans-stilbene derivatives, a gas responsive material has been created which exhibits a high photoluminescence quantum yield, offering new opportunities for chemical sensors. Here, we reveal a nanocomposite material, assembled from azobenzene functionalized graphene oxide and stilbene-MOF, that is capable of luminescent quenching by explosive gases. This unique system displays selectivity to dinitrotoluene (71% quenching) over trinitrotoluene (20% quenching) with sub ppm sensitivity and response times of less than a minute. We show that this implementation of a graphene-based MOF composite provides a unique strategy in the development of molecularly well-defined materials having rapid, reversible, and gas selective fluorescent quenching capabilities. This opens the way for new advances in the assembly of low density frameworks using isomerization suppressed materials.Achieving both high specificity and sensitivity are essential for gas phase chemical detection systems. Recent implementation of Metal-Organic Frameworks (MOFs) have shown great success in separation and storage systems for specific gas molecules. By implementing a MOF structure comprised of Zn2+ coordinated trans-stilbene derivatives, a gas responsive material has been created which exhibits a high photoluminescence quantum yield, offering new opportunities for chemical sensors. Here, we reveal a nanocomposite material, assembled from azobenzene functionalized graphene oxide and stilbene-MOF, that is capable of luminescent quenching by explosive gases. This unique system displays selectivity to dinitrotoluene (71% quenching) over trinitrotoluene (20% quenching) with sub ppm sensitivity and

  6. Numerical Model for Hydrovolcanic Explosions.

    NASA Astrophysics Data System (ADS)

    Mader, Charles; Gittings, Michael

    2007-03-01

    A hydrovolcanic explosion is generated by the interaction of hot magma with ground water. It is called Surtseyan after the 1963 explosive eruption off Iceland. The water flashes to steam and expands explosively. Liquid water becomes water gas at constant volume and generates pressures of about 3GPa. The Krakatoa hydrovolcanic explosion was modeled using the full Navier-Stokes AMR Eulerian compressible hydrodynamic code called SAGE [1] which includes the high pressure physics of explosions. The water in the hydrovolcanic explosion was described as liquid water heated by magma to 1100 K. The high temperature water is treated as an explosive with the hot liquid water going to water gas. The BKW [2] steady state detonation state has a peak pressure of 8.9 GPa, a propagation velocity of 5900 meters/sec and the water is compressed to 1.33 g/cc. [1] Numerical Modeling of Water Waves, Second Edition, Charles L. Mader, CRC Press 2004. [2] Numerical Modeling of Explosions and Propellants, Charles L. Mader, CRC Press 1998.

  7. Dust explosions-cases, causes, consequences, and control.

    PubMed

    Abbasi, Tasneem; Abbasi, S A

    2007-02-09

    Dust explosions pose the most serious and widespread of explosion hazards in the process industry alongside vapour cloud explosions (VCE) and boiling liquid expanding vapour explosions (BLEVE). Dust explosions almost always lead to serious financial losses in terms of damage to facilities and down time. They also often cause serious injuries to personnel, and fatalities. We present the gist of the dust explosion state-of-the-art. Illustrative case studies and past accident analyses reflect the high frequency, geographic spread, and damage potential of dust explosions across the world. The sources and triggers of dust explosions, and the measures with which different factors associated with dust explosions can be quantified are reviewed alongside dust explosion mechanism. The rest of the review is focused on the ways available to prevent dust explosion, and on cushioning the impact of a dust explosion by venting when the accident does take place.

  8. Doping explosive materials for neutron radiographic enhancement.

    NASA Technical Reports Server (NTRS)

    Golliher, K. G.

    1971-01-01

    Discussion of studies relating to the selection of doping materials of high neutron absorption usable for enhancing the neutron radiographic imaging of explosive mixtures, without interfering with the proper chemical reaction of the explosives. The results of the studies show that gadolinium oxide is an excellent material for doping explosive mixtures to enhance the neutron radiographic image.

  9. Doping explosive materials for neutron radiographic enhancement.

    NASA Technical Reports Server (NTRS)

    Golliher, K. G.

    1971-01-01

    Discussion of studies relating to the selection of doping materials of high neutron absorption usable for enhancing the neutron radiographic imaging of explosive mixtures, without interfering with the proper chemical reaction of the explosives. The results of the studies show that gadolinium oxide is an excellent material for doping explosive mixtures to enhance the neutron radiographic image.

  10. Thermally stable, plastic-bonded explosives

    DOEpatents

    Benziger, Theodore M.

    1979-01-01

    By use of an appropriate thermoplastic rubber as the binder, the thermal stability and thermal stress characteristics of plastic-bonded explosives may be greatly improved. In particular, an HMX-based explosive composition using an oil-extended styrene-ethylenebutylene-styrene block copolymer as the binder exhibits high explosive energy and thermal stability and good handling safety and physical properties.

  11. Analysis of Picattiny Sample for Trace Explosives

    SciTech Connect

    Klunder, G; Whipple, R; Carman, L; Spackman, P E; Reynolds, J; Alcaraz, A

    2008-05-23

    The sample received from Picatinny Arsenal was analyzed for trace amounts of high explosives (HE). A complete wash of the surface was performed, concentrated, and analyzed using two sensitive analysis techniques that are capable of detecting numerous types of explosives. No explosives were detected with either test.

  12. Explosive simulants for testing explosive detection systems

    DOEpatents

    Kury, John W.; Anderson, Brian L.

    1999-09-28

    Explosives simulants that include non-explosive components are disclosed that facilitate testing of equipment designed to remotely detect explosives. The simulants are non-explosive, non-hazardous materials that can be safely handled without any significant precautions. The simulants imitate real explosives in terms of mass density, effective atomic number, x-ray transmission properties, and physical form, including moldable plastics and emulsions/gels.

  13. Real-time distributed measurement of detonation velocities inside high explosives with the help of chirped fiber Bragg gratings

    NASA Astrophysics Data System (ADS)

    Magne, Sylvain; Lefrançois, Alexandre; Luc, Jérome; Laffont, Guillaume; Ferdinand, Pierre

    2013-05-01

    Following the pioneering work of the Lawrence Livermore National Laboratory, Chirped Fiber Bragg Gratings are investigated as in situ, real-time, wavelength-position discriminators for measuring detonation speeds inside explosives.

  14. Detonation wave profiles in HMX based explosives

    SciTech Connect

    Gustavsen, R.L.; Sheffield, S.A.; Alcon, R.R.

    1997-11-01

    Detonation wave profiles have been measured in several HMX based plastic bonded explosives including PBX9404, PBX9501, and EDC-37, as well as two HMX powders (coarse and fine) pressed to 65% of crystal density. The powders had 120 and 10 {micro}m average grain sizes, respectively. Planar detonations were produced by impacting the explosive with projectiles launched in a 72-mm bore gas gun. Impactors, impact velocity, and explosive thickness were chosen so that the run distance to detonation was always less than half the explosive thickness. For the high density plastic bonded explosives, particle velocity wave profiles were measured at an explosive/window interface using two VISAR interferometers. PMMA windows with vapor deposited aluminum mirrors were used for all experiments. Wave profiles for the powdered explosives were measured using magnetic particle velocity gauges. Estimates of the reaction zone parameters were obtained from the profiles using Hugoniots of the explosive and window.

  15. Prompt detonation of secondary explosives by laser

    SciTech Connect

    Paisley, D.L.

    1989-01-01

    Secondary high explosives have been promptly detonated by directing a laser beam of various wavelengths from 266 nanometers to 1.06 micron on the surface of the explosives. For this paper ''prompt'' means the excess transit time through an explosive charge is /approximately/250 nanoseconds (or less) less than the accepted full detonation velocity time. Timing between laser pulse, explosive initiation and detonation velocity and function time have been recorded. The laser parameters studied include: wavelength, pulse length, energy and power density, and beam diameter (spot size). Explosives evaluated include: PETN, HNS, HMX, and graphited PETN, HNS, and HMX. Explosive parameters that have been correlated with optical parameters include: density, surface area, critical diameter (spot size), spectral characteristics and enhance absorption. Some explosives have been promptly detonated over the entire range of wavelengths, possibly by two competing initiating mechanisms. Other explosives could not be detonated at any of the wavelengths or power densities tested. 8 refs., 12 figs., 1 tab.

  16. Optical detection of explosives: spectral signatures for the explosive bouquet

    NASA Astrophysics Data System (ADS)

    Osborn, Tabetha; Kaimal, Sindhu; Causey, Jason; Burns, William; Reeve, Scott

    2009-05-01

    Research with canines suggests that sniffer dogs alert not on the odor from a pure explosive, but rather on a set of far more volatile species present in an explosive as impurities. Following the explosive trained canine example, we have begun examining the vapor signatures for many of these volatile impurities utilizing high resolution spectroscopic techniques in several molecular fingerprint regions. Here we will describe some of these high resolution measurements and discuss strategies for selecting useful spectral signature regions for individual molecular markers of interest.

  17. Insulation performance physics in extremal conditions, initiated in explosive magnetic ultra-high power current shaping device

    SciTech Connect

    Chernyshev, V.K.; Petrukhin, A.A.; Kuzyajev, A.K.

    1993-12-31

    PulsE installations, based on a disc explosive magnetic generator (EMG), having a current openning switch, enabling the transfer of > 10 MJ of magnetic energy into the liner loads at a power level of >10 (sup 13) W, have been worked out. Energy from explosive magnetic installations to energy releasing devices, ponderomotor units (PU) is transferred through a transmission line, the main element of which is electrically strong insulation. Insulator peculiarities of a transmission line are described.

  18. Spectroscopic Measurement of High-Frequency Electric Fields in the Interaction of Explosive Debris Plasma with Ambient, Magnetized Background Plasma

    NASA Astrophysics Data System (ADS)

    Bondarenko, Anton; Schaeffer, Derek; Everson, Erik; Clark, Eric; Vincena, Stephen; van Compernolle, Bart; Tripathi, Shreekrishna; Constantin, Carmen; Niemann, Chris

    2014-10-01

    The explosive expansion of dense, high-beta debris plasma into relatively tenuous, magnetized background plasma is relevant to a wide variety of astrophysical and space environments. Electric fields play a fundamental role in the coupling of momentum and energy from debris to background, and emission spectroscopy provides a powerful diagnostic for assessing electric fields via the Stark effect. A recent experiment utilizing a unique experimental platform at UCLA that combines the Large Plasma Device and the Raptor laser facility has investigated the super-Alfvénic, quasi-perpendicular expansion of a laser-produced carbon (C) debris plasma through a preformed, ambient, magnetized helium (He) background plasma via emission spectroscopy. Spectral profiles of the He II 468.6 nm line have been analyzed via single-mode and multi-mode time-dependent Stark broadening models for hydrogen-like ions, yielding large magnitude (~100 kV/cm), high-frequency (~100 GHz) electric fields. The measurements suggest the development of an electron beam-plasma instability, and a simple instability saturation model demonstrates that the measured electric field magnitudes are feasible under the experimental conditions.

  19. SOLID PHASE MICROEXTRACTION SAMPLING OF HIGH EXPLOSIVE RESIDUES IN THE PRESENCE OF RADIONUCLIDES AND RADIONUCLIDE SURROGATE METALS

    SciTech Connect

    Duff, M; S Crump, S; Robert02 Ray, R; Donna Beals, D

    2007-04-13

    The Federal Bureau of Investigation (FBI) Laboratory currently does not have on site facilities for handling radioactive evidentiary materials and there are no established FBI methods or procedures for decontaminating high explosive (HE) evidence while maintaining evidentiary value. One experimental method for the isolation of HE residue involves using solid phase microextraction or SPME fibers to remove residue of interest. Due to their high affinity for organics, SPME fibers should have little affinity for most metals. However, no studies have measured the affinity of radionuclides for SPME fibers. The focus of this research was to examine the affinity of dissolved radionuclide ({sup 239/240}Pu, {sup 238}U, {sup 237}Np, {sup 85}Sr, {sup 133}Ba, {sup 137}Cs, {sup 60}Co and {sup 226}Ra) and stable radionuclide surrogate metals (Sr, Co, Ir, Re, Ni, Ba, Cs, Nb, Zr, Ru, and Nd) for SPME fibers at the exposure conditions that favor the uptake of HE residues. Our results from radiochemical and mass spectrometric analyses indicate these metals have little measurable affinity for these SPME fibers during conditions that are conducive to HE residue uptake with subsequent analysis by liquid or gas phase chromatography with mass spectrometric detection.

  20. Luminescent metal-organic framework-functionalized graphene oxide nanocomposites and the reversible detection of high explosives.

    PubMed

    Lee, Ji Ha; Jaworski, Justyn; Jung, Jong Hwa

    2013-09-21

    Achieving both high specificity and sensitivity are essential for gas phase chemical detection systems. Recent implementation of Metal-Organic Frameworks (MOFs) have shown great success in separation and storage systems for specific gas molecules. By implementing a MOF structure comprised of Zn(2+) coordinated trans-stilbene derivatives, a gas responsive material has been created which exhibits a high photoluminescence quantum yield, offering new opportunities for chemical sensors. Here, we reveal a nanocomposite material, assembled from azobenzene functionalized graphene oxide and stilbene-MOF, that is capable of luminescent quenching by explosive gases. This unique system displays selectivity to dinitrotoluene (71% quenching) over trinitrotoluene (20% quenching) with sub ppm sensitivity and response times of less than a minute. We show that this implementation of a graphene-based MOF composite provides a unique strategy in the development of molecularly well-defined materials having rapid, reversible, and gas selective fluorescent quenching capabilities. This opens the way for new advances in the assembly of low density frameworks using isomerization suppressed materials.

  1. Observations of high-frequency P wave earthquake and explosion spectra compared with ω-3, ω-2, and sharpe source models

    NASA Astrophysics Data System (ADS)

    Walter, William R.; Brune, James N.; Priestley, Keith F.; Fletcher, Jon

    1988-06-01

    Observations of 10-, 20-, and 30-Hz P wave spectral amplitudes from earthquakes and explosions are compared with the Archambeau [1968, 1972] earthquake model featuring a P wave falloff of ω-3 beyond the corner frequency, a modified Brune [1970, 1971] earthquake model with ω-2 falloff, and the Sharpe [1942] explosion model which has a ω-2 falloff. The Archambeau and Sharpe models have been, in part, the basis of a proposal by Evernden et al. [1986] that high-frequency (≈30 Hz) seismic energy could provide an effective solution to the problem of detection and identification of low-yield coupled and fully decoupled underground nuclear explosions. The observations of earthquakes show an increase in spectral amplitude with moment approximately in agreement with the ω-2 falloff model and, for larger moments, in disagreement with the ω-3 model. Comparison of theoretical and actual seismograms narrow-band filtered at 30 Hz shows that in part the increase in spectral amplitude of earthquakes is due to the complex and long duration of the rupture process and not because of an increase in an impulsive first arrival like that characteristic of an explosion. The 30-Hz amplitudes for explosions show much scatter, and many events have a spectral falloff greater than the ω-2 predicted by the Sharpe model. Whether this is due entirely to attenuation or is the actual source spectrum is not determined. High stress drop earthquakes are predicted to have larger spectral amplitudes than the Sharpe model. Thus any discrimination technique using high-frequency P wave spectra should probably take into account differences in pulse shape and amplitude in the time domain.

  2. Advanced high-explosive flux compression generator development: The CN-3 series

    NASA Astrophysics Data System (ADS)

    Freeman, B. L.; Sheppard, M. G.; Fowler, C. M.

    1992-08-01

    A very successful series of three flux compression generator (FCG) experiments and one hydro-only test, designed to quantify the performance capabilities and limitations of high-current, high-field, high-power coaxial FCG's, is reported. In the last test, the CN-3 FCG produced a peak current of greater than 150 MA with a final doubling time of less than 10 micro-s into a 2-nH inductive load. Experimental results are in excellent agreement with extensive preshot and postshot one-dimensional (1D) and two-dimensional (2D) magnetohydrodynamic (MHD) calculations.

  3. Advanced high-explosive flux compression generator development: The CN-III series

    SciTech Connect

    Freeman, B.L.; Sheppard, M.G.; Fowler, C.M.

    1992-08-01

    A very successful series of three flux compression generator (FCG) experiments and one hydro-only test, designed to quantify the performance capabilities and limitations of high-current, high-field, high-power coaxial FCGs, is reported. In the last test, the CN-III FCG produced a peak current of >150 MA with a final doubling time of <10{mu}s into a 2-nH inductive load. Experimental results are in excellent agreement with extensive preshot and postshot one-dimensional (1D) and two-dimensional (2D) magnetohydrodynamic (MHD) calculations.

  4. PHETS (Permanent High Explosive Test Site) Lightning Hardening Program: Misty Picture Event

    DTIC Science & Technology

    1988-06-01

    1967), wire, electrical, insulated high temperature. d. Rural Electrification Administration Specifications--REA PE-210 (April, 1967), Crystalline...November 1961) Insulation, Electrical, (Amendment 5: June 20, 1968) Synthetic-Resin Composition, Nonrigid e. Rural Electrification Administration

  5. NEW GUN CAPABILITY WITH INTERCHANGABLE BARRELS TO INVESTIGATE LOW VELOCITY IMPACT REGIMES AT THE LAWRENCE LIVERMORE NATIONAL LABORATORY HIGH EXPLOSIVES APPLICATIONS FACILITY

    SciTech Connect

    Vandersall, K S; Behn, A; Gresshoff, M; Jr., L F; Chiao, P I

    2009-09-16

    A new gas gun capability is being activated at Lawrence Livermore National Laboratories located in the High Explosives Applications Facility (HEAF). The single stage light gas (dry air, nitrogen, or helium) gun has interchangeable barrels ranging from 25.4 mm to 76.2 mm in diameter with 1.8 meters in length and is being fabricated by Physics Applications, Inc. Because it is being used for safety studies involving explosives, the gun is planned for operation inside a large enclosed firing tank, with typical velocities planned in the range of 10-300 m/s. Three applications planned for this gun include: low velocity impact of detonator or detonator/booster assemblies with various projectile shapes, the Steven Impact test that involves impact initiation of a cased explosive target, and the Taylor impact test using a cylindrical explosive sample impacted onto a rigid anvil for fracture studies of energetic materials. A highlight of the gun features, outline on work in progress for implementing this capability, and discussion of the planned areas of research will be included.

  6. Coupled High Speed Imaging and Seismo-Acoustic Recordings of Strombolian Explosions at Etna, July 2014: Implications for Source Processes and Signal Inversions.

    NASA Astrophysics Data System (ADS)

    Taddeucci, J.; Del Bello, E.; Scarlato, P.; Ricci, T.; Andronico, D.; Kueppers, U.; Cannata, A.; Sesterhenn, J.; Spina, L.

    2015-12-01

    Seismic and acoustic surveillance is routinely performed at several persistent activity volcanoes worldwide. However, interpretation of the signals associated with explosive activity is still equivocal, due to both source variability and the intrinsically limited information carried by the waves. Comparison and cross-correlation of the geophysical quantities with other information in general and visual recording in particular is therefore actively sought. At Etna (Italy) in July 2014, short-lived Strombolian explosions ejected bomb- to lapilli-sized, molten pyroclasts at a remarkably repeatable time interval of about two seconds, offering a rare occasion to systematically investigate the seismic and acoustic fields radiated by this common volcanic source. We deployed FAMoUS (FAst, MUltiparametric Setup for the study of explosive activity) at 260 meters from the vents, recording more than 60 explosions in thermal and visible high-speed videos (50 to 500 frames per second) and broadband seismic and acoustic instruments (1 to 10000 Hz for the acoustic and from 0.01 to 30 Hz for the seismic). Analysis of this dataset highlights nonlinear relationships between the exit velocity and mass of ejecta and the amplitude and frequency of the acoustic signals. It also allows comparing different methods to estimate source depth, and to validate existing theory on the coupling of airwaves with ground motion.

  7. CH3-π interaction of explosives with cavity of a TPE macrocycle: the key cause for highly selective detection of TNT.

    PubMed

    Feng, Hai-Tao; Wang, Jin-Hua; Zheng, Yan-Song

    2014-11-26

    The identification of explosives is critical for analyzing the background of terrorism activities and the origin of pollution aroused by the explosives, but it is a challenge to discriminate the explosives with a very similar structure. Herein we report a series of TPE-based macrocycles with an AIE effect for the 0.2-4 ppb level detection of TNT among a number of nitro-aromatic compounds through fluorescence quenching in natural water sources, whereas the contact mode approach using portable paper sensors exhibited a high sensitivity for the detection of TNT at 1.0 × 10(-13) M level. The reliability of the quantitative analysis has been confirmed by HPLC. Our findings demonstrate that the TPE-based macrocycles have great potential as excellent sensors for TNT. Moreover, it was found for the first time that the macrocycles could selectively recognize nitroaromatics explosives bearing methyl group through a CH3-π interactions, and even exhibit a sole selectivity for TNT among the very difficultly differentiating nitroaromatics including trinitrophenol and trinitrobenzene.

  8. Indium Nitride: A New Material for High Efficiency, Compact, 1550NM Laser-Based Terahertz Sources in Explosives Detection and Concealed Weapons Imaging

    DTIC Science & Technology

    2006-11-01

    INDIUM NITRIDE: A NEW MATERIAL FOR HIGH EFFICIENCY, COMPACT, 1550NM LASER-BASED TERAHERTZ SOURCES IN EXPLOSIVES DETECTION AND CONCEALED WEAPONS...nitride (InN) is identified as a promising terahertz (THz) emitter based on the optical and electronic properties of high quality In- and N-face...significant improvements in THz emitters. 1. INTRODUCTION The terahertz region of the electromagnetic spectrum, lying between microwave frequencies

  9. A flow integrated DSD hydrodynamics strategy for computing the motion of detonation of insensitive high explosives on an Eulerian grid

    SciTech Connect

    Short, Mark; Aslam, Tariq D

    2010-01-01

    The detonation structure in many insensitive high explosives consists of two temporally disparate zones of heat release. In PBX 9502, there is a fast reaction zone ({approx} 25 ns) during which reactants are converted to gaseous products and small carbon clusters, followed by a slower regime ({approx} 250 ns) of carbon coagulation. A hybrid approach for determining the propagation of two-stage heat release detonations has been developed that utilizes a detonation shock dynamics (DSD) based strategy for the fast reaction zone with a direct hydrodynamic simulation of the flow in the slow zone. Unlike a standard DSD/programmed bum formulation, the evolution of the fast zone DSD-like surface is coupled to the flow in the slow reaction zone. We have termed this formulation flow integrated detonation shock dynamics (FIDSD). The purpose of the present paper is to show how the FIDSD formulation can be applied to detonation propagation on an Eulerian grid using an algorithm based on level set interface tracking and a ghost fluid approach.

  10. Micellar extraction and high performance liquid chromatography-ultra violet determination of some explosives in water samples.

    PubMed

    Babaee, Saeed; Beiraghi, Asadollah

    2010-03-03

    An analytical method based on the cloud point extraction combined with high performance liquid chromatography is used for the extraction, separation and determination of four explosives; octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazine (HMX), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), 2,4,6-trinitrotoluene (TNT) and pentaerythritol tetranitrate (PETN). These compounds are extracted by using of Triton X-114 and cetyl-trimethyl ammonium bromide (CTAB). After extraction, the samples were analyzed using a HPLC-UV system. The parameters affecting extraction efficiency (such as Triton X-114 and CTAB concentrations, amount of Na(2)SO(4), temperature, incubation and centrifuge times) were evaluated and optimized. Under the optimum conditions, the preconcentration factor was 40 and the improvement factors of 34, 29, 61 and 42 with detection limits of 0.09, 0.14, 0.08 and 0.40 (microg L(-1)) were obtained for HMX, RDX, TNT and PETN, respectively. The proposed method was successfully applied to the determination of these compounds in water samples and showed recovery percentages of 97-102% with RSD values of 2.13-4.92%.

  11. In-situ monitoring of flow-permeable surface area of high explosive powder using small sample masses

    SciTech Connect

    Maiti, Amitesh; Han, Yong; Zaka, Fowzia; Gee, Richard H.

    2015-02-17

    To ensure good performance of high explosive devices over long periods of time, initiating powders need to maintain their specific surface area within allowed margins during the entire duration of deployment. A common diagnostic used in this context is the Fisher sub-sieve surface area (FSSA). Furthermore, commercial permeametry instruments measuring the FSSA requires the utilization of a sample mass equal to the crystal density of the sample material, an amount that is often one or two orders of magnitude larger than the typical masses found in standard detonator applications. Here we develop a customization of the standard device that can utilize just tens of milligram samples, and with simple calibration yield FSSA values at ac curacy levels comparable to the standard apparatus. This necessitated a newly designed sample holder, made from a material of low coefficient of thermal expansion, which is conveniently transferred between an aging chamber and a re-designed permeametry tube. This improves the fidelity of accelerated aging studies by allowing measurement on the same physical sample at various time - instants during the aging process, and by obviating the need for a potentially FSSA-altering powder re-compaction step. We used the customized apparatus to monitor the FSSA evolution of a number of undoped and homolog-doped PETN powder samples that were subjected to artificial aging for several months at elevated temperatures. These results, in conjunction with an Arrhenius-based aging model were used to assess powder-coarsening - rates under long-term storage.

  12. High aspect ratio micro-explosions in the bulk of sapphire generated by femtosecond Bessel beams

    NASA Astrophysics Data System (ADS)

    Rapp, L.; Meyer, R.; Giust, R.; Furfaro, L.; Jacquot, M.; Lacourt, P. A.; Dudley, J. M.; Courvoisier, F.

    2016-09-01

    Femtosecond pulses provide an extreme degree of confinement of light matter-interactions in high-bandgap materials because of the nonlinear nature of ionization. It was recognized very early on that a highly focused single pulse of only nanojoule energy could generate spherical voids in fused silica and sapphire crystal as the nanometric scale plasma generated has energy sufficient to compress the material around it and to generate new material phases. But the volumes of the nanometric void and of the compressed material are extremely small. Here we use single femtosecond pulses shaped into high-angle Bessel beams at microjoule energy, allowing for the creation of very high 100:1 aspect ratio voids in sapphire crystal, which is one of the hardest materials, twice as dense as glass. The void volume is 2 orders of magnitude higher than those created with Gaussian beams. Femtosecond and picosecond illumination regimes yield qualitatively different damage morphologies. These results open novel perspectives for laser processing and new materials synthesis by laser-induced compression.

  13. High aspect ratio micro-explosions in the bulk of sapphire generated by femtosecond Bessel beams

    PubMed Central

    Rapp, L.; Meyer, R.; Giust, R.; Furfaro, L.; Jacquot, M.; Lacourt, P. A.; Dudley, J. M.; Courvoisier, F.

    2016-01-01

    Femtosecond pulses provide an extreme degree of confinement of light matter-interactions in high-bandgap materials because of the nonlinear nature of ionization. It was recognized very early on that a highly focused single pulse of only nanojoule energy could generate spherical voids in fused silica and sapphire crystal as the nanometric scale plasma generated has energy sufficient to compress the material around it and to generate new material phases. But the volumes of the nanometric void and of the compressed material are extremely small. Here we use single femtosecond pulses shaped into high-angle Bessel beams at microjoule energy, allowing for the creation of very high 100:1 aspect ratio voids in sapphire crystal, which is one of the hardest materials, twice as dense as glass. The void volume is 2 orders of magnitude higher than those created with Gaussian beams. Femtosecond and picosecond illumination regimes yield qualitatively different damage morphologies. These results open novel perspectives for laser processing and new materials synthesis by laser-induced compression. PMID:27669676

  14. A primer on explosives costs

    SciTech Connect

    Paddock, R.C.

    1987-03-01

    There are a multitude of cost centers in the typical coal mine, and almost as many ways to calculate their individual and collective effect on the bottom line. The costs of explosives is, in some ways, very difficult to determine without consideration of drilling, loading, hauling and breaking costs. Saving a nickel in explosive costs, for example, could end up costing a dollar more in crushing expenses. Typically, mines request quotations for explosives products on a weight basis. Were the market one of pure commodities, this would give a valid comparison. However, the energy being purchased often is not considered. The cost of any explosive should be considered in light of the work it can do, not the air it displaces or the price per pound. Consider in essence, the purchase of explosive energy as you would the sale of coal, in terms of dollars per Btu. Recent new developments in explosives technology make the economic implications of blast design and explosive selection more important than ever. Let's look to improve overall production costs through a better understanding of relevant explosive criteria. One has to consider what the explosives parameters really are. A brief review of explosives development history is helpful, plus a review of the secondary production factors reliant upon an effective blast. Due to the many variables, which are site specific, it is beyond the scope of this brief article to cover in detail all aspects. However, this may well raise awareness to the potential cost savings and resultant competitive edge that available high energy blasting agents can give.

  15. The combustion of explosives

    SciTech Connect

    Son, S. F.

    2001-01-01

    The safe use of energetic materials has been scientifically studied for over 100 years. Even with this long history of scientific inquiry, the level of understanding of the important deflagration phenomena in accidental initiations of high explosives remains inadequate to predict the response to possible thermal and mechanical (impact) scenarios. The! search also continues for more well behaved explosives and propellants that perform well, yet are insensitive. Once ignition occurs in an explosive, the question then becomes what the resulting violence will be. The classical view is that simple wave propagation proceeds from the ignition point. Recently, several experiments have elucidated the importance of reactive cracks involved in reaction violence in both thermally ignited experiments and impacted explosives, in contrast to classical assumptions, This work presents a viiw of reaction violence, in both thermal and mechanical insults, that argues for the importance of reactive cracks, rather than simple wave propagation processes. Recent work in this area will be reviewed and presented. Initial results involving novel energetic materials will also be discussed.

  16. Reliable Classification of High Explosive and Chemical/Biological Artillery Using Acoustic Sensors

    DTIC Science & Technology

    2006-10-01

    high pass filtering of the input signal is used to implement the DWT [5]. The resulting banks of dyadic multirate filters split the input signal...Figure 4 – A Multirate Filter Bank used as a Five Level Wavelet Decomposition Tree 2.2 Wavelet Features for Classification Figures 5 (a-c...resulting banks of dyadic multirate filters separate the frequency components into different subbands. – Each pass through gives you resolution of

  17. Explosives Safety Training

    DTIC Science & Technology

    2010-07-13

    Safety Awareness in NATO and Multi- National Operations *Explosives Safety “ Rosetta Stone ” *under development Distance Learning/ Instructor-Led Training...and Multi- National Operations *Explosives Safety “ Rosetta Stone ” Ammo-18 (Basics of Naval Explosives Hazard Control) Ammo-29 (Electrical Explosives...National Operations *Explosives Safety “ Rosetta Stone ” Ammo-47 (Lightning Protection for Air Force Facilities) *Explosives Safety Awareness in NATO and

  18. Explosive radiation in high Andean Hypericum-rates of diversification among New World lineages.

    PubMed

    Nürk, Nicolai M; Scheriau, Charlotte; Madriñán, Santiago

    2013-01-01

    The páramos, high-elevation Andean grasslands ranging from ca. 2800 m to the snow line, harbor one of the fastest evolving biomes worldwide since their appearance in the northern Andes 3-5 million years (Ma) ago. Hypericum (St. John's wort), with over 65% of its Neotropical species, has a center of diversity in these high Mountain ecosystems. Using nuclear rDNA internal transcribed spacer (ITS) sequences of a broad sample of New World Hypericum species we investigate phylogenetic patterns, estimate divergence times, and provide the first insights into diversification rates within the genus in the Neotropics. Two lineages appear to have independently dispersed into South America around 3.5 Ma ago, one of which has radiated in the páramos (Brathys). We find strong support for the polyphyly of section Trigynobrathys, several species of which group within Brathys, while others are found in temperate lowland South America (Trigynobrathys s.str.). All páramo species of Hypericum group in one clade. Within these páramo Hypericum species enormous phenotypic evolution has taken place (life forms from arborescent to prostrate shrubs) evidently in a short time frame. We hypothesize multiple mechanisms to be responsible for the low differentiation in the ITS region contrary to the high morphological diversity found in Hypericum in the páramos. Amongst these may be ongoing hybridization and incomplete lineage sorting, as well as the putative adaptive radiation, which can explain the contrast between phenotypic diversity and the close phylogenetic relationships.

  19. Explosive radiation in high Andean Hypericum—rates of diversification among New World lineages

    PubMed Central

    Nürk, Nicolai M.; Scheriau, Charlotte; Madriñán, Santiago

    2013-01-01

    The páramos, high-elevation Andean grasslands ranging from ca. 2800 m to the snow line, harbor one of the fastest evolving biomes worldwide since their appearance in the northern Andes 3–5 million years (Ma) ago. Hypericum (St. John's wort), with over 65% of its Neotropical species, has a center of diversity in these high Mountain ecosystems. Using nuclear rDNA internal transcribed spacer (ITS) sequences of a broad sample of New World Hypericum species we investigate phylogenetic patterns, estimate divergence times, and provide the first insights into diversification rates within the genus in the Neotropics. Two lineages appear to have independently dispersed into South America around 3.5 Ma ago, one of which has radiated in the páramos (Brathys). We find strong support for the polyphyly of section Trigynobrathys, several species of which group within Brathys, while others are found in temperate lowland South America (Trigynobrathys s.str.). All páramo species of Hypericum group in one clade. Within these páramo Hypericum species enormous phenotypic evolution has taken place (life forms from arborescent to prostrate shrubs) evidently in a short time frame. We hypothesize multiple mechanisms to be responsible for the low differentiation in the ITS region contrary to the high morphological diversity found in Hypericum in the páramos. Amongst these may be ongoing hybridization and incomplete lineage sorting, as well as the putative adaptive radiation, which can explain the contrast between phenotypic diversity and the close phylogenetic relationships. PMID:24062764

  20. Coulomb explosion effect and the maximum energy of protons accelerated by high-power lasers.

    PubMed

    Fourkal, E; Velchev, I; Ma, C-M

    2005-03-01

    The acceleration of light ions (protons) through the interaction of a high-power laser pulse with a double-layer target is theoretically studied by means of two-dimensional particle-in-cell simulations and a one-dimensional analytical model. It is shown that the maximum energy acquired by the accelerated light ions (protons) depends on the physical characteristics of a heavy-ion layer (electron-ion mass ratio and effective charge state of the ions). In our theoretical model, the hydrodynamic equations for both electron and heavy-ion species are solved and the test-particle approximation for the light ions (protons) is applied. The heavy-ion motion is found to modify the longitudinal electric field distribution, thus changing the acceleration conditions for the protons.

  1. Freeze frame analysis on high speed cinematography of Nd/YAG laser explosions in ocular tissues.

    PubMed

    Vernon, S A; Cheng, H

    1986-05-01

    High speed colour cinematography at 400 frames per second was used to photograph both single and train burst Nd/YAG laser applications in ox eyes at threshold energy levels. Measurements of the extent and speed of particle scatter and tissue distortion from the acoustic transient were made from a sequential freeze frame analysis of the films. Particles were observed to travel over 8 mm from the site of Nd/YAG application 20 milliseconds after a single pulse at initial speeds in excess of 20 km/h. The use of train bursts of pulses was seen to increase the number of particles scattered and project the wavefront of particles further from the point of laser application.

  2. Pretreatment of bamboo by ultra-high pressure explosion with a high-pressure homogenizer for enzymatic hydrolysis and ethanol fermentation.

    PubMed

    Jiang, Zehui; Fei, Benhua; Li, Zhiqiang

    2016-08-01

    Bamboo shoots, 2- and 5-year-old bamboo were treated by using a homogenizer in a constant suspended state, a process termed as ultra-high pressure explosion (UHPE). The bamboo powder was heated in 2% NaOH solution at 121°C, and then 100MPa UHPE-treated through a homogenizer. The results verified that UHPE changed the suspension solution of powder into a stick fluid. The contents of lignin were decreased significantly. The bamboo shoots and 2-year-old bamboo were completely hydrolyzed to glucose within 48h by enzymes loading of 15 FPU of cellulase and 30IU of β-glucosidase per gram glucan. Fermentation of enzymatic hydrolyzates with Saccharomyces cerevisiae resulted in about 89.7-95.1% of the theoretical ethanol yield after 24h. Therefore, NaOH+UHPE is argued to be a potential alternative technology for pretreatment of bamboo.

  3. Modeling thermally driven energetic response of high explosives in ALE3D

    SciTech Connect

    Aro, C.; McCallen, R.C.; Neely, R.; Nichols, A.L. III; Sharp, R.

    1998-10-01

    The authors have improved their ability to model the response of energetic materials to thermal stimuli and the processes involved in the energetic response. Traditionally, the analyses of energetic materials have involved coupled thermal transport/chemical reaction codes. This provides only a reasonable estimate of the time and location of ensuing rapid reaction. To predict the violence of the reaction, the mechanical motion must be included in the wide range of time scales associated with the thermal hazard. The ALE3D code has been modified to assess the hazards associated with heating energetic materials in weapons by coupling to thermal transport model and chemistry models. They have developed an implicit time step option to efficiently and accurately compute the hours of heating to reaction of the energetic material. Since, on these longer time scales materials can be expected to have significant motion, it is even more important to provide high-order advection for all components, including the chemical species. They show two examples of coupled thermal/mechanical/chemical models of energetic materials in thermal environments.

  4. Micro-solid-phase extraction coupled to desorption electrospray ionization-high-resolution mass spectrometry for the analysis of explosives in soil.

    PubMed

    Bianchi, Federica; Gregori, Adolfo; Braun, Gabriele; Crescenzi, Carlo; Careri, Maria

    2015-01-01

    Home-made micro-solid-phase extraction (SPE) cartridges using different adsorbent materials were tested for the desorption electrospray ionization-high-resolution mass spectrometry (DESI-HRMS) determination of explosives like 2,4,6-trinitrotoluene, cyclotrimethylene-trinitramine, cyclotetramethylene-tetranitramine, pentaerythritol tetranitrate, and trinitrophenylmethylnitramine in soil samples. Quantitation limits in the low nanogram per kilogram range proved the reliability of the method for the detection of explosives at ultra-trace levels. The reduced sample preparation allowed for low costs and high-throughput analyses. Finally, the superior extraction capability of the method was proved by obtaining DESI-HRMS responses at least five times higher than those achieved by performing DESI-HRMS analyses of solid-liquid extracts spotted onto commercial polytetrafluoroethylene slides.

  5. Shock desensitizing of solid explosive

    SciTech Connect

    Davis, William C

    2010-01-01

    Solid explosive can be desensitized by a shock wave too weak to initiate it promptly, and desensitized explosive does not react although its chemical composition is almost unchanged. A strong second shock does not cause reaction until it overtakes the first shock. The first shock, if it is strong enough, accelerates very slowly at first, and then more rapidly as detonation approaches. These facts suggest that there are two competing reactions. One is the usual explosive goes to products with the release of energy, and the other is explosive goes to dead explosive with no chemical change and no energy release. The first reaction rate is very sensitive to the local state, and the second is only weakly so. At low pressure very little energy is released and the change to dead explosive dominates. At high pressure, quite the other way, most of the explosive goes to products. Numerous experiments in both the initiation and the full detonation regimes are discussed and compared in testing these ideas.

  6. Shock desensitizing of solid explosives

    SciTech Connect

    Davis, William C

    2010-01-01

    Solid explosive can be desensitized by a shockwave too weak to initiate it promptly, and desensitized explosive does not react although its chemical composition is almost unchanged. A strong second shock does not cause reaction until it overtakes the first shock. The first shock, if it is strong enough, accelerates very slowly at first, and then more rapidly as detonation approaches. These facts suggest that there are two competing reactions. One is the usual explosive goes to products with the release of energy, and the other is explosive goes to dead explosive with no chemical change and no energy release. The first reaction rate is very sensitive to the local state, and the second is only weakly so. At low pressure very little energy is released and the change to dead explosive dominates. At high pressure, quite the other way, most of the explosive goes to products. Numerous experiments in both the initiation and the full detonation regimes are discussed and compared in support of these ideas.

  7. Detection of explosives in soils

    DOEpatents

    Chambers, William B.; Rodacy, Philip J.; Phelan, James M.; Woodfin, Ronald L.

    2002-01-01

    An apparatus and method for detecting explosive-indicating compounds in subsurface soil. The apparatus has a probe with an adsorbent material on some portion of its surface that can be placed into soil beneath the ground surface, where the adsorbent material can adsorb at least one explosive-indicating compound. The apparatus additional has the capability to desorb the explosive-indicating compound through heating or solvent extraction. A diagnostic instrument attached to the probe detects the desorbed explosive-indicating compound. In the method for detecting explosive-indicating compounds in soil, the sampling probe with an adsorbent material on at least some portion of a surface of the sampling probe is inserted into the soil to contact the adsorbent material with the soil. The explosive-indicating compounds are then desorbed and transferred as either a liquid or gas sample to a diagnostic tool for analysis. The resulting gas or liquid sample is analyzed using at least one diagnostic tool selected from the group consisting of an ion-mobility spectrometer, a gas chromatograph, a high performance liquid chromatograph, a capillary electrophoresis chromatograph, a mass spectrometer, a Fourier-transform infrared spectrometer and a Raman spectrometer to detect the presence of explosive-indicating compounds.

  8. A fluorescent sensor for highly selective detection of nitroaromatic explosives based on a 2D, extremely stable, metal-organic framework.

    PubMed

    Zhang, Shu-Ran; Du, Dong-Ying; Qin, Jun-Sheng; Bao, Shao-Juan; Li, Shun-Li; He, Wen-Wen; Lan, Ya-Qian; Shen, Ping; Su, Zhong-Min

    2014-03-24

    A 2D, extremely stable, metal-organic framework (MOF), NENU-503, was successfully constructed. It displays highly selective and recyclable properties in detection of nitroaromatic explosives as a fluorescent sensor. This is the first MOF that can distinguish between nitroaromatic molecules with different numbers of NO2 groups. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Application Of An Exploding Wire Capping Shutter To The Study Of Solid High Explosive Charges Using An Ultrahigh-Speed Rotating Mirror Camera

    NASA Astrophysics Data System (ADS)

    Gibb, A. W.; Naylor, R.; Nolan, M. A.; Dempsey, J. B.

    1983-03-01

    The Explosives and Engineering Group at Defence Research Establishment Suffield (DRES) has developed a portable field laboratory containing an ultra-high speed camera (Cordin Model 330A) for the study of detonation processes in solid high explosives. The camera is of the rotating-mirror type, the image being swept repeatedly over stationary film as the mirror rotates. The writing period is continuously adjustable from 40 microseconds to 400 microseconds, but the mechanical shutter closes on a time scale of milliseconds. In order to prevent optical over-write (multiple exposure) of the film due to the highly-luminous cloud of detonation products from the detonating explosive, an auxiliary, rapid-closing shutter must be utilized. This paper describes the successful design and use of an electronically-operated exploding-wire capping shutter which has an activation time predictable to within ±1 microsecond. The shutter principle is the same as that described by Edgerton and Strabalal. The unit developed at DRES has the ability to attenuate light by a factor of three hundred in fifteen microseconds, over a circular viewing area 10.2 cm (4 inches) in diameter.

  10. Understanding Magma Storage Conditions that Produce Highly Explosive Monogenetic Basaltic Eruptions Using Olivine-Hosted Melt Inclusions from Sunset Crater, AZ

    NASA Astrophysics Data System (ADS)

    Allison, C. M.; Roggensack, K.; Clarke, A. B.

    2014-12-01

    To investigate mechanisms of explosive basaltic volcanism, we studied the ca. 1085 AD Sunset Crater eruption in the San Francisco Volcanic Field (SFVF) of northern Arizona. This eruption, the youngest in the SFVF, first featured fissure eruptions (explosive phases 1-2) and a small lava flow, and then activity narrowed to a central vent producing explosive phases 3-8 and two additional lava flows. While the first two phases were Strombolian-style explosions, middle phases (3-5) were subplinian in character and produced an anomalously large tephra deposit. The final phases (6-8) are poorly characterized at this stage. The total erupted volume of lava and tephra is >0.7 km3 DRE of alkali olivine basalt with a large proportion of crystal-free glass and low phenocryst content. We studied 82 primary melt inclusions (MIs) in the largest tephra units (explosive phases 3, 4) to investigate magma volatiles and storage conditions. To prioritize primary volatile contents, we picked rapidly quenched free olivine crystals (Fo 81-85; 0.5-2 mm) and selected large volume MIs (50-180 μm) located near crystal cores for analysis. We observed vapor bubbles in all MIs and also noted rare occurrences of CO2-rich gas inclusions. MIs show little major element variability suggesting little crystal fractionation (K2O 0.8-1.1 wt.%). Post-entrapment crystallization is also minor (2-9%). The MI compositions from the two phases largely overlap, with phase 4 skewed to slightly higher K2O. FTIR spectroscopy shows that the MIs are relatively dry and CO2-rich. Water abundances vary 0.8-1.6 wt.% with a median of 1.25 wt.%, while most MIs have CO2 abundances 1,600-3,400 ppm. Phases 3 and 4 are essentially identical in water content. CO2 contents of phases 3 and 4 show considerable overlap, however the phase 4 MIs are skewed toward high CO2 (>2,500 ppm). These results require a minimum MI entrapment depth of ~11 km from fluid saturation constraints. Overall, the MIs indicate a largely homogeneous

  11. Acute Effects of Pre-Event Lower Limb Massage on Explosive and High Speed Motor Capacities and Flexibility

    PubMed Central

    Arabaci, Ramiz

    2008-01-01

    The aim of this study was to examine the acute effects of pre- performance lower limb massage after warm-up on explosive and high-speed motor capacities and flexibility. Twenty-four physically active healthy Caucasian male subjects volunteered to participate in this study. All subjects were from a Physical Education and Sport Department in a large university in Turkey. The study had a counterbalanced crossover design. Each of the subjects applied the following intervention protocols in a randomised order; (a) massage, (b) stretching, and (c) rest. Before (pre) and after (post) each of the interventions, the 10 meter acceleration (AS), flying start 20 meter sprint (FS), 30 meter sprint from standing position (TS), leg reaction time (LR), vertical jump (VJ) and sit & reach (SR) tests were performed. A Wilcoxon’s signed rank test was used to compare before and after test values within the three interventions (massage, stretching and rest). The data showed a significant worsening, after massage and stretching interventions, in the VJ, LR (only in stretching intervention), AS and TS tests (p < 0.05), and significant improvement in the SR test (p < 0.05). In contrast, the rest intervention led only to a significant decrement in TS performance (p < 0.05). In conclusion, the present findings suggest that performing 10 minute posterior and 5 minute anterior lower limb Swedish massage has an adverse effect on vertical jump, speed, and reaction time, and a positive effect on sit and reach test results. Key pointsPerforming 10 minute posterior and 5 minute anterior lower limb Swedish massages has an adverse affect on vertical jump, speed, and reaction time and a positive effect on sit and reach test results.According to the present results, long duration massage should not be recommended for warm-ups.Larger subject pools are needed to verify these events. PMID:24149965

  12. In-situ monitoring of flow-permeable surface area of high explosive powder using small sample masses

    DOE PAGES

    Maiti, Amitesh; Han, Yong; Zaka, Fowzia; ...

    2015-02-17

    To ensure good performance of high explosive devices over long periods of time, initiating powders need to maintain their specific surface area within allowed margins during the entire duration of deployment. A common diagnostic used in this context is the Fisher sub-sieve surface area (FSSA). Furthermore, commercial permeametry instruments measuring the FSSA requires the utilization of a sample mass equal to the crystal density of the sample material, an amount that is often one or two orders of magnitude larger than the typical masses found in standard detonator applications. Here we develop a customization of the standard device that canmore » utilize just tens of milligram samples, and with simple calibration yield FSSA values at ac curacy levels comparable to the standard apparatus. This necessitated a newly designed sample holder, made from a material of low coefficient of thermal expansion, which is conveniently transferred between an aging chamber and a re-designed permeametry tube. This improves the fidelity of accelerated aging studies by allowing measurement on the same physical sample at various time - instants during the aging process, and by obviating the need for a potentially FSSA-altering powder re-compaction step. We used the customized apparatus to monitor the FSSA evolution of a number of undoped and homolog-doped PETN powder samples that were subjected to artificial aging for several months at elevated temperatures. These results, in conjunction with an Arrhenius-based aging model were used to assess powder-coarsening - rates under long-term storage.« less

  13. Acute effects of pre-event lower limb massage on explosive and high speed motor capacities and flexibility.

    PubMed

    Arabaci, Ramiz

    2008-01-01

    The aim of this study was to examine the acute effects of pre- performance lower limb massage after warm-up on explosive and high-speed motor capacities and flexibility. Twenty-four physically active healthy Caucasian male subjects volunteered to participate in this study. All subjects were from a Physical Education and Sport Department in a large university in Turkey. The study had a counterbalanced crossover design. Each of the subjects applied the following intervention protocols in a randomised order; (a) massage, (b) stretching, and (c) rest. Before (pre) and after (post) each of the interventions, the 10 meter acceleration (AS), flying start 20 meter sprint (FS), 30 meter sprint from standing position (TS), leg reaction time (LR), vertical jump (VJ) and sit & reach (SR) tests were performed. A Wilcoxon's signed rank test was used to compare before and after test values within the three interventions (massage, stretching and rest). The data showed a significant worsening, after massage and stretching interventions, in the VJ, LR (only in stretching intervention), AS and TS tests (p < 0.05), and significant improvement in the SR test (p < 0.05). In contrast, the rest intervention led only to a significant decrement in TS performance (p < 0.05). In conclusion, the present findings suggest that performing 10 minute posterior and 5 minute anterior lower limb Swedish massage has an adverse effect on vertical jump, speed, and reaction time, and a positive effect on sit and reach test results. Key pointsPerforming 10 minute posterior and 5 minute anterior lower limb Swedish massages has an adverse affect on vertical jump, speed, and reaction time and a positive effect on sit and reach test results.According to the present results, long duration massage should not be recommended for warm-ups.Larger subject pools are needed to verify these events.

  14. Explosive signatures: Pre & post blast

    NASA Astrophysics Data System (ADS)

    Bernier, Evan Thomas

    Manuscripts 1 and 2 of this dissertation both involve the pre-blast detection of trace explosive material. The first manuscript explores the analysis of human hair as an indicator of exposure to explosives. Field analysis of hair for trace explosives is quick and non-invasive, and could prove to be a powerful linkage to physical evidence in the form of bulk explosive material. Individuals tested were involved in studies which required handling or close proximity to bulk high explosives such as TNT, PETN, and RDX. The second manuscript reports the results of research in the design and application of canine training aids for non-traditional, peroxide-based explosives. Organic peroxides such as triacetonetriperoxide (TATP) and hexamethylenetriperoxidediamine (HMTD) can be synthesized relatively easily with store-bought ingredients and have become popular improvised explosives with many terrorist groups. Due to the hazards of handling such sensitive compounds, this research established methods for preparing training aids which contained safe quantities of TATP and HMTD for use in imprinting canines with their characteristic odor. Manuscripts 3 and 4 of this dissertation focus on research conducted to characterize pipe bombs during and after an explosion (post-blast). Pipe bombs represent a large percentage of domestic devices encountered by law enforcement. The current project has involved the preparation and controlled explosion of over 90 pipe bombs of different configurations in order to obtain data on fragmentation patterns, fragment velocity, blast overpressure, and fragmentation distance. Physical data recorded from the collected fragments, such as mass, size, and thickness, was correlated with the relative power of the initial device. Manuscript 4 explores the microstructural analysis of select pipe bomb fragments. Shock-loading of the pipe steel led to plastic deformation and work hardening in the steel grain structure as evidenced by optical microscopy and

  15. The Explosive-Degrading Cytochrome P450 System Is Highly Conserved among Strains of Rhodococcus spp.▿

    PubMed Central

    Seth-Smith, Helena M. B.; Edwards, James; Rosser, Susan J.; Rathbone, Deborah A.; Bruce, Neil C.

    2008-01-01

    Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a widely used explosive and a serious environmental pollutant. Nineteen strains of Rhodococcus spp. capable of utilizing RDX as the sole nitrogen source have been isolated. The cytochrome P450 system XplA-XplB, which is responsible for RDX breakdown, is present in 18 of these strains. PMID:18487400

  16. An assessment of high-energy explosives and metal contamination in soil at TA-67 (12), L-Site, and TA-14, Q-Site

    SciTech Connect

    Haywood, W.; McRae, D.; Powell, J.; Harris, B.W.

    1995-01-01

    The results of the field investigation to determine the kind and concentration of explosives found in the soil and on articles at sites known to be contaminated with energetic materials are given in this report. We are concerned about safety and health hazards associated with some explosives, nitro-organics and organic nitrates. Results from the use of the old and new field spot-test kits to detect the presence of energetic materials are given. Also included are data from the high-performance liquid chromatography (HPLC) analyses of acetonitrile extracts from Q-Site soil samples, and data from the energy-dispersive x-ray fluorescence (EDXRF) analyses for hazardous metals on the same samples.

  17. Eigenvalue Detonation of Combined Effects Aluminized Explosives

    NASA Astrophysics Data System (ADS)

    Capellos, Christos; Baker, Ernest; Balas, Wendy; Nicolich, Steven; Stiel, Leonard

    2007-06-01

    This paper reports on the development of theory and performance for recently developed combined effects aluminized explosives. Traditional high energy explosives used for metal pushing incorporate high loading percentages of HMX or RDX, whereas blast explosives incorporate some percentage of aluminum. However, the high blast explosives produce increased blast energies, with reduced metal pushing capability due to late time aluminum reaction. Metal pushing capability refers to the early volume expansion work produced during the first few volume expansions associated with cylinder wall velocities and Gurney energies. Our Recently developed combined effects aluminized explosives (PAX-29C, PAX-30, PAX-42) are capable of achieving excellent metal pushing and high blast energies. Traditional Chapman-Jouguet detonation theory does not explain the observed detonation states achieved by these combined effects explosives. This work demonstrates, with the use of cylinder expansion data and thermochemical code calculations (JAGUAR and CHEETAH), that eigenvalue detonation theory explains the observed behavior.

  18. Proton transfer reaction mass spectrometry for the sensitive and rapid real-time detection of solid high explosives in air and water.

    PubMed

    Jürschik, S; Sulzer, P; Petersson, F; Mayhew, C A; Jordan, A; Agarwal, B; Haidacher, S; Seehauser, H; Becker, K; Märk, T D

    2010-12-01

    Relying on recent developments in proton transfer reaction mass spectrometry (PTR-MS), we demonstrate here the capability of detecting solid explosives in air and in water in real time. Two different proton transfer reaction mass spectrometers have been used in this study. One is the PTR-TOF 8000, which has an enhanced mass resolution (m/Δm up to 8,000) and high sensitivity (~50 cps/ppbv). The second is the high-sensitivity PTR-MS, which has an improved limit of detection of about several hundreds of parts per quadrillion by volume and is coupled with a direct aqueous injection device. These instruments have been successfully used to identify and monitor the solid explosive 2,4,6-trinitrotoluene (TNT) by analysing on the one hand the headspace above small quantities of samples at room temperature and from trace quantities not visible to the naked eye placed on surfaces (also demonstrating the usefulness of a simple pre-concentration and thermal desorption technique) and by analysing on the other hand trace compounds in water down to a level of about 100 pptw. The ability to identify even minute amounts of threat compounds, such as explosives, particularly within a complex chemical environment, is vital to the fight against crime and terrorism and is of paramount importance for the appraisal of the fate and harmful effects of TNT at marine ammunition dumping sites and the detection of buried antipersonnel and antitank landmines.

  19. Simulating intracrater ash recycling during mid-intensity explosive activity: high temperature laboratory experiments on natural basaltic ash

    NASA Astrophysics Data System (ADS)

    D'Oriano, Claudia; Pompilio, Massimo; Bertagnini, Antonella; Cioni, Raffaello; Pichavant, Michel

    2010-05-01

    Direct observations of mid-intensity eruptions, in which a huge amount of ash is generated, indicate that ash recycling is quite common. The recognition of juvenile vs. recycled fragments is not straightforward, and no unequivocal, widely accepted criteria exist to support this. The presence of recycled glassy fragments can hide primary magmatic information, introducing bias in the interpretations of the ongoing magmatic and volcanic activity. High temperature experiments were performed at atmospheric pressure on natural samples to investigate the effects of reheating on morphology, texture and composition of volcanic ash. Experiments simulate the transformation of juvenile glassy fragments that, falling into the crater or in the upper part of the conduit, are recycled by following explosions. Textural and compositional modifications obtained in laboratory are compared with similar features observed in natural samples in order to identify some main general criteria to be used for the discrimination of recycled material. Experiments were carried out on tephra produced during Strombolian activity, fire fountains and continuous ash emission at Etna, Stromboli and Vesuvius. Coarse glassy clasts were crushed in a nylon mortar in order to create an artificial ash, and then sieved to select the size interval of 1-0.71 mm. Ash shards were put in a sealed or open quartz tube, in order to prevent or to reproduce effects of air oxidation. The tube was suspended in a HT furnace at INGV-Pisa and kept at different temperatures (up to to 1110°C) for increasing time (0.5-12 hours). Preliminary experiments were also performed under gas flux conditions. Optical and electron microscope observations indicate that high temperature and exposure to the air induce large modifications on clast surface, ranging from change in color, to incipient plastic deformation till complete sintering. Significant change in color of clasts is strictly related to the presence of air, irrespective of

  20. Degassing vs. eruptive styles at Mt. Etna volcano (Sicily, Italy): Volatile stocking, gas fluxing, and the shift from low-energy to highly-explosive basaltic eruptions

    NASA Astrophysics Data System (ADS)

    Moretti, Roberto; Métrich, Nicole; Di Renzo, Valeria; Aiuppa, Alessandro; Allard, Patrick; Arienzo, Ilenia

    2017-04-01

    Basaltic magmas can transport and release large amounts of volatiles into the atmosphere, especially in subduction zones, where slab-derived fluids enrich the mantle wedge. Depending on magma volatile content, basaltic volcanoes thus display a wide spectrum of eruptive styles, from common Strombolian-type activity to Plinian events. Mt. Etna in Sicily, is a typical basaltic volcano where the volatile control on such a variable activity can be investigated. Based on a melt inclusion study in products from Strombolian or lava-fountain activity to Plinian eruptions, here we show that for the same initial volatile content, different eruptive styles reflect variable degassing paths throughout the composite Etnean plumbing system. The combined influence of i) crystallization, ii) deep degassing and iii) CO2 gas fluxing can explain the evolution of H2O, CO2, S and Cl in products from such a spectrum of activity. Deep crystallization produces the CO2-rich gas fluxing the upward magma portions, which will become buoyant and easily mobilized in small gas-rich batches stored within the plumbing system. When reaching gas dominated conditions (i.e., a gas/melt mass ratio of 0.3 and CO2,gas/H2Ogas molar ratio 5 ), these will erupt effusively or mildly explosively, whilst in case of the 122 BC Plinian eruption, open-system degassing conditions took place within the plumbing system, such that continuous CO2-fluxing determined gas accumulation on top of the magmatic system. The emission of such a cap in the early eruptive phase triggered the arrival of deep H2O-rich whose fast decompression and bubble nucleation lead to the highly explosive character, enhanced by abundant microlite crystallization and consequent increase of magma effective viscosity. This could explain why open system basaltic systems like Etna may experience highly explosive or even Plinian episodes during eruptions that start with effusive to mildly explosive phases. The proposed mechanism also determines a

  1. Chromospheric explosions

    NASA Technical Reports Server (NTRS)

    Doschek, G. A.; theory. (3) Resolved: Most chromospheric h; theory. (3) Resolved: Most chromospheric h

    1986-01-01

    Three issues relative to chromospheric explosions were debated. (1) Resolved: The blue-shifted components of x-ray spectral lines are signatures of chromospheric evaporation. It was concluded that the plasma rising with the corona is indeed the primary source of thermal plasma observed in the corona during flares. (2) Resolved: The excess line broading of UV and X-ray lines is accounted for by a convective velocity distribution in evaporation. It is concluded that the hypothesis that convective evaporation produces the observed X-ray line widths in flares is no more than a hypothesis. It is not supported by any self-consistent physical theory. (3) Resolved: Most chromospheric heating is driven by electron beams. Although it is possible to cast doubt on many lines of evidence for electron beams in the chromosphere, a balanced view that debaters on both sides of the question might agree to is that electron beams probably heat the low corona and upper chromosphere, but their direct impact on evaporating the chromosphere is energetically unimportant when compared to conduction. This represents a major departure from the thick-target flare models that were popular before the Workshop.

  2. Explosion of Leidenfrost Droplets

    NASA Astrophysics Data System (ADS)

    Moreau, Florian; Colinet, Pierre; Dorbolo, Stephane

    2012-11-01

    When a drop is released on a plate heated above a given temperature, a thin layer of vapour can isolate the droplet so that it levitates over the plate. This effect was first reported by Leidenfrost in 1756. However, this fascinating subject remains an active field of research in both fundamental and applied researches. In this work, we focus on what happens when surfactant is added to the drop. The aim is to study the influence of a decrease of the surface tension. Surprisingly, as the droplet evaporates, suddenly it explodes. The evolution of the droplet and the resulting explosion are followed using a high speed camera. We show that when a critical concentration of surfactant is reached inside the drop, a shell of surfactant is formed leading to the explosion. The authors would like to thank FNRS for financial support. This work is financially supported by ODILE project (Contract No. FRFC 2.4623.11).

  3. Explosive Spot Joining of Metals

    NASA Technical Reports Server (NTRS)

    Bement, Laurence J. (Inventor); Perry, Ronnie B. (Inventor)

    1997-01-01

    The invention is an apparatus and method for wire splicing using an explosive joining process. The apparatus consists of a prebend, U-shaped strap of metal that slides over prepositioned wires. A standoff means separates the wires from the strap before joining. An adhesive means holds two ribbon explosives in position centered over the U-shaped strap. A detonating means connects to the ribbon explosives. The process involves spreading strands of each wire to be joined into a flat plane. The process then requires alternating each strand in alignment to form a mesh-like arrangement with an overlapped area. The strap slides over the strands of the wires. and the standoff means is positioned between the two surfaces. The detonating means then initiates the ribbon explosives that drive the strap to accomplish a high velocity. angular collision between the mating surfaces. This collision creates surface melts and collision bonding resulting in electron-sharing linkups.

  4. Superenantioselective chiral surface explosions.

    PubMed

    Gellman, Andrew J; Huang, Ye; Feng, Xu; Pushkarev, Vladimir V; Holsclaw, Brian; Mhatre, Bharat S

    2013-12-26

    Chiral inorganic materials predated life on Earth, and their enantiospecific surface chemistry may have played a role in the origins of biomolecular homochirality. However, enantiospecific differences in the interaction energies of chiral molecules with chiral surfaces are small and typically lead to modest enantioselectivities in adsorption, catalysis, and chemistry on chiral surfaces. To yield high enantioselectivities, small energy differences must be amplified by reaction mechanisms such as autocatalytic surface explosions which have nonlinear kinetics. Herein, we report the first observations of superenantiospecificity resulting from an autocatalytic surface explosion reaction of a chiral molecule on a naturally chiral surface. R,R- and S,S-tartaric acid decompose via a vacancy-mediated surface explosion mechanism on Cu single crystal surfaces. When coupled with surface chirality, this leads to decomposition rates that exhibit extraordinarily high enantiospecificity. On the enantiomorphs of naturally chiral Cu(643)(R&S), Cu(17,5,1)(R&S), Cu(531)(R&S) and Cu(651)(R&S) single crystal surfaces, R,R- and S,S-tartaric acid exhibit enantiospecific decomposition rates that differ by as much as 2 orders of magnitude, despite the fact that the effective rates constants for decomposition differ by less than a factor of 2.

  5. Ammonium nitrate explosive systems

    DOEpatents

    Stinecipher, Mary M.; Coburn, Michael D.

    1981-01-01

    Novel explosives which comprise mixtures of ammonium nitrate and an ammonium salt of a nitroazole in desired ratios are disclosed. A preferred nitroazole is 3,5-dinitro-1,2,4-triazole. The explosive and physical properties of these explosives may readily be varied by the addition of other explosives and oxidizers. Certain of these mixtures have been found to act as ideal explosives.

  6. Initiation of preshocked high explosives PBX-9404, PBX-9502, PBX-9501, monitored with in-material magnetic gauging

    SciTech Connect

    Mulford, R.N.; Sheffield, S.A.; Alcon, R.R.

    1993-08-01

    Desensitization of explosives by preshocking is being studied using the well-supported plane shock waves generated by a gas gun. Evolution of the waves in the explosive is monitored using in-material multiple magnetic gauges to measure particle velocity in the lagrangian frame, over {approx} 3{mu}s of run. PBX-9404, PBX-9502 have been studied, at pressures up to 10.5 GPa. A substantial extension of the run to detonation is observed in PBX-9404, with the run beginning approximately at the end of the preshocked region. A reactive wave is observed while the preshock persists in both PBX-9404 and PBX-9501, but evidently does not contribute to the detonation wave or shorten the run to detonation. PBX-9502 is inert at pressures accessible with the gas gun, but serves to clarify the progress of multiple shocks over the off-Hugoniot EOS surface and the shock dynamics of wave coalescence.

  7. Final Environmental Assessment for the High Explosive Research and Development Complex’s Proposed Long Term Upgrade and Expansion

    DTIC Science & Technology

    2012-06-01

    uninhabited explosive storage and/or testing chambers . Construction and/or renovation of research and administration facilities may lead to limited...Air Force Base, Florida. September 2008. Merriam-Webster. 2009. Merriam-Webster Online Dictionary , www.merriam-webster.com (Accessed February...action would not affect Authorizes acquisition of Land Acquisition for tourism and/or outdoor recreation. environmentally endangered lands and

  8. Generation of High-Frequency P and S Wave Energy by Rock Fracture During a Buried Explosion

    DTIC Science & Technology

    2015-07-20

    symmetry is broken. Spherical symmetry is broken by the following: tectonic pre-stress, preferred orientation of pre-existing fractures (anisotropic rock...generated by laboratory explosions in plates of “candy glass”. Candy glass (or break-away glass) is used in the movie industry to simulate glass fracture in...9 4.1. Experimental Results – Candy-Glass Plates .......................................................9 4.2. Measurements of the Mechanical

  9. Observations of a bromine explosion event coincident with the arrival of Arctic haze in the Canadian high Arctic

    NASA Astrophysics Data System (ADS)

    Bognar, Kristof; Zhao, Xiaoyi; Strong, Kimberly; Hayes, Patrick L.; Tremblay, Samantha; Chang, Rachel Y.-W.

    2017-04-01

    Exponential build-up of bromine in the polar troposphere is linked to severe multi-day ozone depletion events in springtime. The exact origins of, and the meteorological conditions required for these 'bromine explosions' are, however, not well understood. On March 19-21, 2016, a bromine explosion was detected at Eureka, Nunavut, Canada (80.1°N, 86.4°W). BrO slant column densities were retrieved from measurements made by a Multi-Axis Differential Optical Absorption Spectroscopy spectrometer. Ozonesonde data indicate that a compete depletion of near-surface ozone also took place in the same period. The bromine explosion was initiated by strong winds and blowing snow, while a stable boundary layer returned for the last day of the event. It is likely that bromine release was localized near Eureka, and both the snowpack and aerosols contributed. Scanning Mobility Particle Sizer data show that the bromine enhancement coincided with the onset of an Arctic haze event. This work investigates whether acidification from the haze contributed to the local release of bromine.

  10. Comparative outcome of bomb explosion injuries versus high-powered gunshot injuries of the upper extremity in a civilian setting.

    PubMed

    Luria, Shai; Rivkin, Gurion; Avitzour, Malka; Liebergall, Meir; Mintz, Yoav; Mosheiff, Ram

    2013-03-01

    Explosion injuries to the upper extremity have specific clinical characteristics that differ from injuries due to other mechanisms. To evaluate the upper extremity injury pattern of attacks on civilian targets, comparing bomb explosion injuries to gunshot injuries and their functional recovery using standard outcome measures. Of 157 patients admitted to the hospital between 2000 and 2004, 72 (46%) sustained explosion injuries and 85 (54%) gunshot injuries. The trauma registry files were reviewed and the patients completed the DASH Questionnaire (Disabilities of Arm, Shoulder and Hand) and SF-12 (Short Form-12) after a minimum period of 1 year. Of the 157 patients, 72 (46%) had blast injuries and 85 (54%) had shooting injuries. The blast casualties had higher Injury Severity Scores (47% vs. 22% with a score of > 16, P = 0.02) and higher percent of patients treated in intensive care units (47% vs. 28%, P = 0.02). Although the Abbreviated Injury Scale score of the upper extremity injury was similar in the two groups, the blast casualties were found to have more bilateral and complex soft tissue injuries and were treated surgically more often. No difference was found in the SF-12 or DASH scores between the groups at follow up. The casualties with upper extremity blast injuries were more severely injured and sustained more bilateral and complex soft tissue injuries to the upper extremity. However, the rating of the local injury to the isolated limb is similar, as was the subjective functional recovery.

  11. Highly explosive eruption of the monogenetic 8.6 ka BP La Vache et Lassolas scoria cone complex (Chaîne des Puys, France)

    NASA Astrophysics Data System (ADS)

    Jordan, S. C.; Le Pennec, J.-L.; Gurioli, L.; Roche, O.; Boivin, P.

    2016-03-01

    The eruption of the trachy-basaltic La Vache and Lassolas cone complex was the youngest eruption (ca. 8.6 ka BP) and one of the most violent in the Chaîne des Puys, France. Here we present field data and results of grain size, componentry and clast density measurements of different layers of the widespread tephra deposit that is associated with this cone-forming eruption. Our data indicates five main eruption phases comprising a vent-opening phase, a second sustained highly explosive phase, a third and fourth violent Strombolian phase and a fifth dominantly effusive phase. The layer formed by the opening phase is rich in lithic material, which was previously considered to be the result of phreatomagmatic activity. The data presented here on the componentry and textures of the pyroclastic material contradict this hypothesis. We propose instead that the material of the basal layer results from fragmentation caused by the explosion of a first arriving gas-dominated phase. The variations in eruption intensity during the main eruption phases are interpreted here to be the result of gas segregation within the plumbing system and fluxes in the magma ascent rate during the eruption. Significant amount of gas segregation is indicated by the deposition of both gas-poor and gas-rich material and by the presence of plate tephra. This is also supported by the simultaneous ejection of tephra and lava from both cones during most of the explosive activity. We suggest that gas segregation occurred within shallow intrusions and that fresh ascending material in the main conduit mixed with degassed material that flow back into the conduit from the intrusion before fragmentation. The interaction of the ascending magma and the opening of intrusions may have controlled the evolution and explosivity of the eruption. The high explosivity at the beginning of the eruption and the wide dispersal area, demonstrate that scoria cone eruptions in monogenetic fields can impose a major threat to

  12. Looking for a correlation between infrasound and volcanic gas in strombolian explosions by using high resolution UV spectroscopy and thermal imagery

    NASA Astrophysics Data System (ADS)

    Delle Donne, Dario; Tamburello, Giancarlo; Ripepe, Maurizio; Aiuppa, Alessandro

    2014-05-01

    According to the linear theory of sound, acoustic pressure propagating in a homogeneous atmosphere can be modelled in terms of the rate of change of a volumetric source. At open-vent volcanoes, this acoustic source process is commonly related to the explosive dynamics triggered by the rise, expansion and bursting of a gas slug at the magma free surface with the conduit. Just before an explosion, the magma surface will undergo deformation by the expanding gas slug. The deformation of the magma surface will then produce an equivalent displacement of the atmosphere, inducing a volumetric compression and generating an excess pressure that scales to the rate of volumetric change of the atmosphere displaced. Linear theory of sound thus predicts that pressure amplitude of infrasonic waves associated to volcanic explosions should be generated by the first time-derivative of the gas mass flux during the burst. In some cases a correlation between the first time-derivative and the SO2 mass flux has been found. However no clear correlation has yet been established between infrasonic amplitude and total ejected gas mass; therefore, the origin of infrasound in volcanic systems remains matter of debate. In the framework of the FP7-ERC BRIDGE Project, we tested different possible hypotheses on the acoustic source model, by correlating infrasound with the total gas mass retrieved from high-resolution UV spectroscopy techniques (UV camera). Experiments were conducted at Stromboli volcano (Italy), where we also employed a thermal camera to measure the total fragments/gas mass. Both techniques allowed independent estimation of total mass flux of gas and fragments within the volcanic plume. During the experiments, explosions detected by the UV camera emitted between 2 and 55 kg SO2, corresponding to SO2 peak fluxes of 0.1-0.8 kg/s. SO2 mass was converted into a total (maximum) erupted gas of 1310 kg, which is generating a peak pressure of ~8 Pa recorded at ~450 m from the source vent

  13. Deciphering between highly-explosive surges and block-and-ash flows from decompression experiments: example of Mt. Pelée (Martinique, F.W.I)

    NASA Astrophysics Data System (ADS)

    Martel, C.

    2012-04-01

    Surges and block-and-ash flows (BAF) are two eruptive styles generated from destruction of silicic lava domes. Yet, the highly energetic nature of the surges contrasts with the mildly-explosive valley-channelled emplacement of the BAFs. The occurrence of one or the other eruptive styles, and the associated differences in risk assessment, is well illustrated at Mt Pelée (e.g. the devastating surge of 8 May 1902). This rises questioning about the generation of dome explosivity. Decompression-induced crystallization experiments have been conducted to simulate magma ascent in the volcanic conduit, in order to infer magma ascent conditions and rates that may lead to either explosive of effusive eruptions. The starting material is Mt Pelée rhyolitic interstitial melt (76-77 wt. % SiO2) and the experiments consisted in three consecutive steps: melt hydration (850°C, 200 MPa, H2O saturation and undersaturation), isothermal decompression (Pf of 5-10 MPa; rate from 0.003 to 25 MPa/min), and annealing at Pf (up to 15 days). Two samples were cooled by 25°C and 50°C at Pf. The experiments generated three types of crystals: pre-, syn-, and post-decompression crystals. The textures and compositions of the experimental plagioclases have been compared to Mt Pelée's plagioclase microlites to infer eruption dynamics. The results suggest that dome and BAF magmas ascend within more than 4-5 days, giving time for syn-decompression crystallization around pre-existent microlites. In contrast, surge magmas ascended within less than ~4 days, without significantly crystallizing in the volcanic conduit. Microlite crystallization massively occurs at dome depth, forcing gas pressurization and subsequent magma fragmentation. The extent and violence of dome destruction may depend on the size/age of the dome, with large/old domes favouring mildly-explosive BAFs, whereas small/young protodomes may generate highly-explosive surges.

  14. Trace explosives sensor testbed (TESTbed)

    NASA Astrophysics Data System (ADS)

    Collins, Greg E.; Malito, Michael P.; Tamanaha, Cy R.; Hammond, Mark H.; Giordano, Braden C.; Lubrano, Adam L.; Field, Christopher R.; Rogers, Duane A.; Jeffries, Russell A.; Colton, Richard J.; Rose-Pehrsson, Susan L.

    2017-03-01

    A novel vapor delivery testbed, referred to as the Trace Explosives Sensor Testbed, or TESTbed, is demonstrated that is amenable to both high- and low-volatility explosives vapors including nitromethane, nitroglycerine, ethylene glycol dinitrate, triacetone triperoxide, 2,4,6-trinitrotoluene, pentaerythritol tetranitrate, and hexahydro-1,3,5-trinitro-1,3,5-triazine. The TESTbed incorporates a six-port dual-line manifold system allowing for rapid actuation between a dedicated clean air source and a trace explosives vapor source. Explosives and explosives-related vapors can be sourced through a number of means including gas cylinders, permeation tube ovens, dynamic headspace chambers, and a Pneumatically Modulated Liquid Delivery System coupled to a perfluoroalkoxy total-consumption microflow nebulizer. Key features of the TESTbed include continuous and pulseless control of trace vapor concentrations with wide dynamic range of concentration generation, six sampling ports with reproducible vapor profile outputs, limited low-volatility explosives adsorption to the manifold surface, temperature and humidity control of the vapor stream, and a graphical user interface for system operation and testing protocol implementation.

  15. Trends in explosive contamination.

    PubMed

    Oxley, Jimmie C; Smith, James L; Resende, Elmo; Pearce, Evan; Chamberlain, Thomas

    2003-03-01

    This study sought to assign a rough order of magnitude for the amount of explosive residue likely to be available in real-world searches for clandestine explosives. A variety of explosives (TNT, TATP, HMX, AN, RDX, PETN) in various forms (powder, flake, detonating cord, plastic) were carefully weighed or cut into containers, and the amount of residue inadvertently remaining on the work area, hands, or containers was quantified. This was used to evaluate the spillage potential of each explosive. The adhesion of each explosive to a glass surface was quantified from amount of explosive adhering to the inside of a glass vial into which the explosive had been placed and then removed by vigorous tapping. In powdered form, most of the explosives--TNT, PETN, RDX, HMX, and TATP--exhibited similar spillage and adhesion to glass. However, PETN as sheet explosive and plasticized RDX (C-4), showed very little potential to contaminate surfaces, either by spillage or adhesion to glass.

  16. Macro-Scale Reactive Flow Model for High-Explosive Detonation in Support of ASCI Weapon Safety Milepost

    SciTech Connect

    Reaugh, J E

    2002-01-03

    Explosive grain-scale simulations are not practical for weapon safety simulations. Indeed for nearly ideal explosives with reaction zones of order 500 {micro}m, even reactive flow models are not practical for weapon safety simulations. By design, reactive flow models must resolve the reaction zone, which implies computational cells with dimension of order 50 {micro}m for such explosives. The desired result for a simulation in which the reaction zone is not resolved is that the explosive behaves as an ideal one. The pressure at the shock front rises to the Chapman-Jouget (CJ) pressure with a reaction zone dimension that is like that of a shock propagating in an unreactive medium, on the order of a few computational cells. It should propagate with the detonation velocity that is determined by the equation of state of the products. In the past, this was achieved in one dimensional simulations with ''beta-burn'', a method in which the extent of conversion to final product is proportional to the approach of the specific volume in the shock front to the specific volume of the CJ state. One drawback with this method is that there is a relatively long build-up to steady detonation that is typically 50 to 100 computational cells. The need for relatively coarsely zoned simulations in two dimensions lead to ''program-burn'' by which the time to detonation can be determined by a simple ray-tracing algorithm when there are no barriers or shadows. Complications arise in two and three dimensions to the extent that some calculations of the lighting time in complex geometry can give incorrect results. We sought to develop a model based on reactive flow that might help the needs of the Weapon Safety Simulation milepost. Important features of the model are: (1) That it be useable with any equation of state description of the explosive product gases including both JWL and LEOS table forms. (2) That it exhibits the desired dependence on zone size. We believe that the model described

  17. Air Activation Following an Atmospheric Explosion

    SciTech Connect

    Lowrey, Justin D.; McIntyre, Justin I.; Prichard, Andrew W.; Gesh, Christopher J.

    2013-03-13

    In addition to thermal radiation and fission products, nuclear explosions result in a very high flux of unfissioned neutrons. Within an atmospheric nuclear explosion, these neutrons can activate the various elemental components of natural air, potentially adding to the radioactive signature of the event as a whole. The goal of this work is to make an order-of-magnitude estimate of the total amount of air activation products that can result from an atmospheric nuclear explosion.

  18. Explosive laser light initiation of propellants

    DOEpatents

    Piltch, Martin S.

    1993-01-01

    A improved initiator for artillery shell using an explosively generated laser light to uniformly initiate the propellent. A small quantity of a high explosive, when detonated, creates a high pressure and temperature, causing the surrounding noble gas to fluoresce. This fluorescence is directed into a lasing material, which lases, and directs laser light into a cavity in the propellant, uniformly initiating the propellant.

  19. Explosive laser light initiation of propellants

    DOEpatents

    Piltch, M.S.

    1993-05-18

    A improved initiator for artillery shell using an explosively generated laser light to uniformly initiate the propellent. A small quantity of a high explosive, when detonated, creates a high pressure and temperature, causing the surrounding noble gas to fluoresce. This fluorescence is directed into a lasing material, which lases, and directs laser light into a cavity in the propellant, uniformly initiating the propellant.

  20. Pathways of sulfur release and redox state track the change from low-energy to highly-explosive eruptions at Mt. Etna (Sicily)

    NASA Astrophysics Data System (ADS)

    Moretti, Roberto; Marini, Luigi; Aiuppa, Alessandro; Métrich, Nicole; Gambardella, Barbara; Hunziker, Johannes

    2010-05-01

    Many basaltic volcanoes are characterized by large amounts of volatiles, most often reflecting fluid release from subducting slabs and consequent injection in the above mantle wedge. Because of this, basaltic volcanoes can experience a wide spectrum of activity, up to Plinian. At Mt. Etna, high-energy Plinian eruptions took place in the past (e.g., 122 BC), and still represent the major volcanic threat for the town of Catania and its surroundings. Joint melt inclusion-based investigation of sulfur release and bulk rock S-isotope study from classic Strombolian or lava-fountain based activity to Plinian eruptions may provide useful indications to discriminate the evolution to either high or low-energy eruptions. We show here that different Etna magmas follow different paths of sulfur elimination. Depending on initial water contents and oxidation states, Etnean magmas can soon reach the limit of sulfide saturation or get rid of sulfur on degassing only. Melt inclusion data indicate that the magma involved in the high-energy Plinian eruption of 122 BC is richer in sulfate than other magmas. The relationship between the high sulfate contents in melts, hence system oxidation, and the energy of the eruption does not seem to be fortuitous and reflects involvement of the hydrous-rich and oxidized parental source of magma, deep seated in a fluid-contaminated mantle. Consistent with melt inclusion findings, S-isotope data support the idea that most oxidized conditions known for Etna could be considered as a proxy for the most violent explosive eruptions, such as the 122 BC Plinian event. Because the whole plumbing system is dominated by CO2 and invested by gas-fluxing, melt dehydration is a common process. Dehydrated magma portions are also more reduced than those ascending from the water-rich source. In light of this, and due to the clear role of water as oxidizing agent, we propose that the explosivity associated with oxidized Etna magmas reflects the fast ascent of deep