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Sample records for hmx plastic-bonded explosives

  1. Shock induced shear strength in an HMX based plastic bonded explosive

    Science.gov (United States)

    Millett, J. C. F.; Taylor, P.; Appleby-Thomas, G.

    2017-01-01

    The shock induced mechanical response of an HMX based plastic bonded explosive (PBX) has been investigated in terms of the shear strength. Results show that shear strength increases with impact stress. However comparison with the calculated elastic response of both the PBX and pure HMX suggests that the overall mechanical response is controlled by the HMX crystals, with the near liquid like nature of the binder phase having a minimal contribution.

  2. Pilot-scale base hydrolysis processing of HMX-based plastic-bonded explosives

    Energy Technology Data Exchange (ETDEWEB)

    Flesner, R.L.; Dell`Orco, P.C.; Spontarelli, T.; Bishop, R.L.; Skidmore, C.B.; Uher, K.; Kramer, J.F.

    1997-10-01

    Los Alamos National Laboratory has demonstrated that many energetic materials can be rendered non-energetic via reaction with sodium hydroxide or ammonia. This process is known as base hydrolysis. A pilot scale reactor has been developed to process up to 20 kg of plastic bonded explosive in a single batch operation. In this report, we discuss the design and operation of the pilot scale reactor for the processing of PBX 9404, a standard Department of Energy plastic bonded explosive containing HMX and nitrocellulose. Products from base hydrolysis, although non-energetic, still require additional processing before release to the environment. Decomposition products, destruction efficiencies, and rates of reaction for base hydrolysis will be presented. Hydrothermal processing, previously known as supercritical water oxidation, has been proposed for converting organic products from hydrolysis to carbon dioxide, nitrogen, and nitrous oxide. Base hydrolysis in combination with hydrothermal processing may yield a viable alternative to open burning/open detonation for destruction of many energetic materials.

  3. Pilot-scale base hydrolysis processing of HMX-based plastic-bonded explosives

    Energy Technology Data Exchange (ETDEWEB)

    Flesner, R.L.; Dell`orco, P.C.; Spontarelli, T.; Bishop, R.L.; Skidmore, C.; Uher, K.J.; Kramer, J.F.

    1996-07-01

    Los Alamos National Laboratory has demonstrated that many energetic materials can be rendered non-energetic via reaction with sodium hydroxide or ammonia. This process is known as base hydrolysis. A pilot scale reactor has been developed to process up to 20 kg of plastic bonded explosive in a single batch operation. In this report, we discuss the design and operation of the pilot scale reactor for the processing of PBX 9404, a standard Department of Energy plastic bonded explosive containing HMX and nitrocellulose. Products from base hydrolysis, although non-energetic, still require additional processing before release to the environment Decomposition products, destruction efficiencies, and rates of reaction for base hydrolysis will be presented. Hydrothermal processing, previously known as supercritical water oxidation, has been proposed for converting organic products from hydrolysis to carbon dioxide, nitrogen, and nitrous oxide. Base hydrolysis in combination with hydrothermal processing may yield a viable alternative to open burning/open detonation for destruction of many energetic materials.

  4. Thermal decomposition and kinetics of plastic bonded explosives based on mixture of HMX and TATB with polymer matrices

    Directory of Open Access Journals (Sweden)

    Arjun Singh

    2017-02-01

    Full Text Available This work describes thermal decomposition behaviour of plastic bonded explosives (PBXs based on mixture of l,3,5,7-tetranitro- 1,3,5,7-tetrazocane (HMX and 2,4,6- triamino-1,3,5-trinitrobenzene (TATB with Viton A as polymer binder. Thermal decomposition of PBXs was undertaken by applying simultaneous thermal analysis (STA and differential scanning calorimetry (DSC to investigate influence of the HMX amount on thermal behavior and its kinetics. Thermogravimetric analysis (TGA indicated that the thermal decomposition of PBXs based on mixture of HMX and TATB was occurred in a three-steps. The first step was mainly due to decomposition of HMX. The second step was ascribed due to decomposition of TATB, while the third step was occurred due to decomposition of the polymer matrices. The thermal decomposition % was increased with increasing HMX amount. The kinetics related to thermal decomposition were investigated under non-isothermal for a single heating rate measurement. The variation in the activation energy of PBXs based on mixture of HMX and TATB was observed with varying the HMX amount. The kinetics from the results of TGA data at various heating rates under non-isothermal conditions were also calculated by Flynn–Wall–Ozawa (FWO and Kissinger-Akahira-Sunose (KAS methods. The activation energies calculated by employing FWO method were very close to those obtained by KAS method. The mean activation energy calculated by FWO and KAS methods was also a good agreement with the activation energy obtained from single heating rate measurement in the first step decomposition.

  5. Studies on Physico-Mechanical and Explosive Characteristics of RDX/HMX-Based Castable Plastic-Bonded Explosives

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    J. S. Gharia

    1998-01-01

    Full Text Available Conventional cast explosives (RDX/TNT have major drawbacks of poor mechanical properties,shrinkages and higher sensitivity .These properties can be improved by applying plastic bindersystems. The plastic-bonded explosive (PBX is a composite material in which solid explosive particles are dispersed in a polymer matrix. The present paper describes the development of anitramine/hydroxy-terminated polybutadiene (HTPB-based castable PBX. The PBXs were processed as per standard procedures. Bimodal/trimodal particle size system was selected to reach asolid loading of 88 wt per cent. High solid loading was made possible through proper combination ofcoarse/fine ratio of solid ingredients, which was based on a number of tap density experiments.Processability of the binder system was studied by using various wetting agents as well as by selectingbinder/plasticizer ratios. Mechanical properties of the PBXs were enhanced by different crosslinkingagents. The explosive properties ofPBXs including detonation velocity , processability and sensitivityto different types of stimuli, were studied. The results show that PBXs can be manufactured withdetonation properties better than those of composition B/octol with the added advantages of superiorthermal and sensitivity characteristics.

  6. Microstructural Characterization of Plastic Bonded Explosives

    Science.gov (United States)

    Yeager, John; Hooks, Daniel; Bahr, David

    2010-03-01

    Plastic bonded explosives (PBX), a mixture of hard, anisotropic grains in a compliant matrix, represent an interesting case for understanding composite mechanical response and failure. PBX 9501 (0.95 cyclotetramethylene tetranitramine [HMX], 0.05 polymer binder) is relatively safe formulation of HMX, which is thought to be due to the high compliance of the binder. Crack formation between the crystals and the binder has been observed in this and many other systems and is usually the failure mechanism of PBX materials under mechanical strain. Thus the properties of the crystal-binder interface are important for development of failure models. The interfacial properties of PBX 9501 as well as an inert simulant have been characterized using several methods. Surface energies of several polymer binders and various crystallographic faces of HMX have been determined with a contact angle measurement technique, allowing for thermodynamic work of adhesion at the interface to be calculated. Surface roughness of the crystal faces has been measured with atomic force microscopy (AFM). PBX formulation methods are suspected to lead to a diffuse interface, but the nature of this interface has not previously been characterized in detail. Here, the coherence of the interface has been studied using tapping mode AFM for modulus contrast, and these findings are correlated with results from diffraction techniques.

  7. Autonomous characterization of plastic-bonded explosives

    Science.gov (United States)

    Linder, Kim Dalton; DeRego, Paul; Gomez, Antonio; Baumgart, Chris

    2006-08-01

    Plastic-Bonded Explosives (PBXs) are a newer generation of explosive compositions developed at Los Alamos National Laboratory (LANL). Understanding the micromechanical behavior of these materials is critical. The size of the crystal particles and porosity within the PBX influences their shock sensitivity. Current methods to characterize the prominent structural characteristics include manual examination by scientists and attempts to use commercially available image processing packages. Both methods are time consuming and tedious. LANL personnel, recognizing this as a manually intensive process, have worked with the Kansas City Plant / Kirtland Operations to develop a system which utilizes image processing and pattern recognition techniques to characterize PBX material. System hardware consists of a CCD camera, zoom lens, two-dimensional, motorized stage, and coaxial, cross-polarized light. System integration of this hardware with the custom software is at the core of the machine vision system. Fundamental processing steps involve capturing images from the PBX specimen, and extraction of void, crystal, and binder regions. For crystal extraction, a Quadtree decomposition segmentation technique is employed. Benefits of this system include: (1) reduction of the overall characterization time; (2) a process which is quantifiable and repeatable; (3) utilization of personnel for intelligent review rather than manual processing; and (4) significantly enhanced characterization accuracy.

  8. Modeling cookoff of HMX based PBX explosives

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, Michael L.

    2017-03-01

    We have previously developed a PBX 9501 cookoff model for the plastic bonded explosive PBX 9501 consisting of 95 wt% octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazoncine (HMX), 2.5 wt% Estane® 5703 (a polyurethane thermoplastic), and 2.5 wt% of a nitroplasticizer (NP): BDNPA/F, a 50/50 wt% eutectic mixture bis(2,2-dinitropropyl)-acetal (BDNPA) and bis(2,2-dinitropropyl)-formal (BDNPF). This fivestep model includes desorption of water, decomposition of the NP to form NO2, reaction of the NO2 with Estane and HMX, and decomposition of HMX [1]. This model has been successfully validated with data from six laboratories with scales ranging from 2 g to more than 2.5 kg of explosive. We have determined, that the PBX 9501 model can be used to predict cookoff of other plastic bonded explosives containing HMX and an inert binder, such as LX-04 consisting of 85 wt% HMX and 15 wt% Viton A (vinylidine fluoride/hexafluoropropylene copolymer), LX-07 (90 wt% HMX and 10 wt% Viton A), LX- 10-0 (95 wt% HMX and 5 wt% Viton A), and LX-14 consisting of 95.5 wt % HMX and 4.5 wt% Estane® 5702-F1 (a polyurethane thermoplastic). Normally our cookoff models are verified using Sandia’s Instrumented Thermal Initiation (SITI) experiment. However, SITI data for LX-04, LX-07, LX-10-0, and LX-14 are not available at pressed density; although, some molding powder SITI data on LX-10-0 and LX-14 exists. Tarver and Tran [2] provide some one-dimensional time-to-explosion (ODTX) data for these explosives. The applicability of the PBX 9501 model to LX-04, LX-07, LX-10-0, AND LX-14 was made using this ODTX data [2]. The PBX 9501 model is applied to these other explosives by accounting for the correct amount of HMX in the explosive and limiting the NP reaction. We have found the PBX 9501 model to be useful for predicting the response of these PBXs to abnormal thermal environments such as fire.

  9. Energetic materials: crystallization, characterization and insensitive plastic bonded explosives

    NARCIS (Netherlands)

    Heijden, A.E.D.M. van der; Creyghton, Y.L.M.; Marino, E.; Bouma, R.H.B.; Scholtes, G.J.H.G.; Duvalois, W.; Roelands, C.P.M.

    2008-01-01

    The product quality of energetic materials is predominantly determined by the crystallization process applied to produce these materials. It has been demonstrated in the past that the higher the product quality of the solid energetic ingredients, the less sensitive a plastic bonded explosive contain

  10. Energetic materials: crystallization, characterization and insensitive plastic bonded explosives

    NARCIS (Netherlands)

    Heijden, A.E.D.M. van der; Creyghton, Y.L.M.; Marino, E.; Bouma, R.H.B.; Scholtes, G.J.H.G.; Duvalois, W.; Roelands, C.P.M.

    2008-01-01

    The product quality of energetic materials is predominantly determined by the crystallization process applied to produce these materials. It has been demonstrated in the past that the higher the product quality of the solid energetic ingredients, the less sensitive a plastic bonded explosive

  11. Experimental investigation of the reaction-build-up for plastic bonded explosive JOB-9003

    Directory of Open Access Journals (Sweden)

    Xu Zhang

    2017-05-01

    Full Text Available In order to measure the shock initiation behavior of JOB-9003 explosives, Al-based embedded multiple electromagnetic particle velocity gauge technique has been developed. In addition, a gauge element called the shock tracker has been used to monitor the progress of the shock front as a function of time, thus providing a position–time trajectory of the wave front as it moves through the explosive sample. The data is used to determine the position and time for shock to detonation transition. All the experimental results show that the rising-up time of Al-based electromagnetic particle velocity gauge is very short (<20 ns; the reaction-build-up velocity profiles and the position–time for shock to detonation transition of HMX-based plastic bonded explosive (PBX JOB-9003 with 1–8 mm depth from the origin of the impact plane under different initiation pressures were obtained with high accuracy.

  12. Modeling shock responses of plastic bonded explosives using material point method

    Science.gov (United States)

    Shang, Hailin; Zhao, Feng; Fu, Hua

    2017-01-01

    Shock responses of plastic bonded explosives are modeled using material point method as implemented in the Uintah Computational Framework. Two-dimensional simulation model was established based on the micrograph of PBX9501. Shock loading for the explosive was performed by a piston moving at a constant velocity. Unreactive simulation results indicate that under shock loading serious plastic strain appears on the boundary of HMX grains. Simultaneously, the plastic strain energy transforms to thermal energy, causing the temperature to rise rapidly on grain boundary areas. The influence of shock strength on the responses of explosive was also investigated by increasing the piston velocity. And the results show that with increasing shock strength, the distribution of plastic strain and temperature does not have significant changes, but their values increase obviously. Namely, the higher the shock strength is, the higher the temperature rise will be.

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

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    Elsharkawy Karim

    2017-01-01

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

  14. In Situ Imaging during Compression of Plastic Bonded Explosives for Damage Modeling

    Directory of Open Access Journals (Sweden)

    Virginia W. Manner

    2017-06-01

    Full Text Available The microstructure of plastic bonded explosives (PBXs is known to influence behavior during mechanical deformation, but characterizing the microstructure can be challenging. For example, the explosive crystals and binder in formulations such as PBX 9501 do not have sufficient X-ray contrast to obtain three-dimensional data by in situ, absorption contrast imaging. To address this difficulty, we have formulated a series of PBXs using octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX crystals and low-density binder systems. The binders were hydroxyl-terminated polybutadiene (HTPB or glycidyl azide polymer (GAP cured with a commercial blend of acrylic monomers/oligomers. The binder density is approximately half of the HMX, allowing for excellent contrast using in situ X-ray computed tomography (CT imaging. The samples were imaged during unaxial compression using micro-scale CT in an interrupted in situ modality. The rigidity of the binder was observed to significantly influence fracture, crystal-binder delamination, and flow. Additionally, 2D slices from the segmented 3D images were meshed for finite element simulation of the mesoscale response. At low stiffness, the binder and crystal do not delaminate and the crystals move with the material flow; at high stiffness, marked delamination is noted between the crystals and the binder, leading to very different mechanical properties. Initial model results exhibit qualitatively similar delamination.

  15. Specific heat and thermal conductivity of explosives, mixtures, and plastic-bonded explosives determined experimentally

    Energy Technology Data Exchange (ETDEWEB)

    Baytos, J.F.

    1979-09-01

    The specific heat and thermal conductivity of explosives and plastic-bonded explosives of interest to WX operations, determined experimentally, are reported in three tables. Specific heat was determined by differential scanning calorimetry against sapphire standards. Thermal conductivity was determined by two means: the guarded hot-plate method or the differential scanning calorimeter comparative method on miniature samples.

  16. The evolution of microstructural changes in pressed HMX explosives

    Energy Technology Data Exchange (ETDEWEB)

    Skidmore, C.B.; Phillips, D.S.; Howe, P.M.; Mang, J.T.; Romero, J.A.

    1998-12-31

    Recently developed techniques for investigating the microstructure of plastic-bonded explosives have been applied to HMX explosives pressed to various levels of porosity. Microstructural changes in PBX 9501 area followed from the early stages of prill consolidation through typical density to very low porosity (0.6%). As porosity is reduced, the following sequence is observed. Large inter- and intra-prill voids are eliminated with first damage to HMX crystals occurring at prill boundaries. This is followed by increased incidence of crystal twinning and cracking. At the lowest porosities, spall pullout artifacts are observed, cracks associated with particle contact points are more obvious, and the results of intercrystalline indentation or intergrowth migration processes are apparent. A comparison is made, at lowest porosities achieved, with PX 9404 and X-0242 (a formulation like PBX 9501 with higher binder volume). Possible implications on porosity trends in shock sensitivity data are discussed.

  17. Thermal expansion of PBX 9501 and PBX 9502 plastic-bonded explosives

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Darla Graff [Los Alamos National Laboratory; Brown, Geoff W [Los Alamos National Laboratory; Deluca, Racci [Los Alamos National Laboratory; Giambra, Anna [Los Alamos National Laboratory; Sandstrom, Mary [Los Alamos National Laboratory

    2009-01-01

    Two applications of thermal expansion measurements on plastic-bonded explosive (PBX) composites are described. In the first dilatometer application, thermal expansion properties of HMX-based PBX 9501 are measured over a broad thermal range that includes glass and domain-restructuring transitions in the polymeric binder. Results are consistent with other thermal measurements and analyses performed on the composite, as well as on the binder itself. The second application used the dilatometer to distinguish the reversible and irreversible components of thermal expansion in PBX 9502, a TATB-based explosive. Irreversible expansion of the composite is believed to derive from the highly-anisotropic coefficient of thermal expansion (CTE) values measured on single T A TB crystals, although the mechanism is not well understood. Effects of specimen density, thermal ramp rate, and thermal range variation (warm first or cold first) were explored, and the results are presented and discussed. Dilatometer measurements are ongoing towards gaining insight into the mechanism(s) responsible for PBX 9502 irreversible thermal expansion.

  18. Aspects of the Tribology of the Plastic Bonded Explosive (PBX) 9404

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, D M; Chandler, J B

    2004-07-08

    The coefficient of friction, {mu}, of the plastic bonded explosive (PBX) 9404 was measured on stainless steel, aluminum, Teflon and the explosive itself as a function of temperature between ambient and 135 C at a rotational speed of 0.0025 rad/sec{sup -1}. An optical profilometer was used to analyze the mean surface roughness, R{sub a}, of the various materials. PBX 9404 is a composite of the explosive 1,3,5,7-tetranitroazacyclooctane (HMX) chloroethyl phosphate (CEF) and nitrocellulose in an 96/3/3 weight ratio. The average roughness of the pressed explosive surface was R{sub a} = 1.37 {micro}m. The coefficient of friction for PBX 9404 on stainless steel of R{sub a} = 0.40 {micro}m increased from 0.22 at ambient to 0.34 at 95 C. Above this temperature {mu} decreased to about 0.23 at 125 C. Similar behavior was observed with aluminum with R{sub a} = 0.31 {micro}m. The coefficient of friction increased from about 0.08 at ambient to 0.48 at 115 C. Above this temperature, {mu} tended to decrease slightly. The coefficient of friction against Teflon of R{sub a} = 0.054 {micro}m was sigmoidal, increasing from about 0.3 at ambient to about at 0.49 {+-} 0.002 above 115 C. Against a PBX 9404 counter surface, the coefficient of friction averaged 0.54 over the entire test temperature range, but tended to increase during the measurement, probably due to adhesion of the nitrocellulose to itself.

  19. Literature review of the lifetime of DOE materials: Aging of plastic bonded explosives and the explosives and polymers contained therein

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, C.E.; Woodyard, J.D. [West Texas A and M Univ., Canyon, TX (United States); Rainwater, K.A. [Texas Tech Univ., Lubbock, TX (United States); Lightfoot, J.M. [Pantex Plant, Amarillo, TX (United States); Richardson, B.R. [Engineered Carbons, Inc., Borger, TX (United States)

    1998-09-01

    There are concerns about the lifetime of the nation`s stockpile of high explosives (HEs) and their components. The DOE`s Core Surveillance and Enhanced Surveillance programs specifically target degradation of HE, binders, and plastic-bonded explosives (PBXs) for determination of component lifetimes and handling procedures. The principal goal of this project is to identify the decomposition mechanisms of HEs, plasticizers, and plastic polymer binders resulting from exposure to ionizing radiation, heat, and humidity. The primary HEs of concern are 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) and 1,3,5,7-tetranitro-1,3,5,7-tetraazocyclooctane (HMX). Hexahydro-1,3,5-triazine (RDX) is closely related to these two compounds and is also included in the literature review. Both Kel-F 800 and Estane are polymers of interest. A stabilizer, Irganox 1010, and an energetic plasticizer that is a blend of acetaldehyde 2,2-dinitropropyl acetal, are also of interest, but the focus of this report will be on the explosives and polymers. This presents a literature review that provides background on the synthesis, degradation, and techniques to analyze TATB, HMX, RDX, Kel-F 800, Estane, and the PBXs of these compounds. As there are many factors that can influence degradation of materials, the degradation discussion will be divided into sections based on each factor and how it might affect the degradation mechanism. The factors reviewed that influence the degradation of these materials are exposure to heat, UV- and {gamma}-irradiation, and the chemistry of these compounds. The report presents a recently compiled accounting of the available literature. 80 refs., 7 figs.

  20. Detonation wave profiles measured in plastic bonded explosives using 1550 nm photon doppler velocimetry (PDV)

    Energy Technology Data Exchange (ETDEWEB)

    Gustavsen, Richard L [Los Alamos National Laboratory; Bartram, Brian D [Los Alamos National Laboratory; Sanchez, Nathaniel (nate) J [Los Alamos National Laboratory

    2009-01-01

    We present detonation wave profiles measured in two TATB based explosives and two HMX based explosives. Profiles were measured at the interface of the explosive and a Lithium-Fluoride (LiF) window using 1550 nm Photon Doppler Velocimetry (PDV). Planar detonations were produced by impacting the explosive with a projectile launched in a gas-gun. The impact state was varied to produce varied distance to detonation, and therefore varied support of the Taylor wave following the Chapman-Jouget (CJ) or sonic state. Profiles from experiments with different support should be the same between the Von-Neumann (VN) spike and CJ state and different thereafter. Comparison of profiles with differing support, therefore, allows us to estimate reaction zone lengths. For the TATB based explosive, a reaction zone length of {approx} 3.9 mm, 500 ns was measured in EDC-35, and a reaction zone length of {approx} 6.3 mm, 800 ns was measured in PBX 9502 pre-cooled to -55 C. The respective VN spike state was 2.25 {+-} 0.05 km/s in EDC-35 and 2.4 {+-} 0.1 km/s in the cooled PBX 9502. We do not believe we have resolved either the VN spike state (> 2.6 km/s) nor the reaction zone length (<< 50 ns) in the HMX based explosives.

  1. Detonation Wave Profiles Measured in Plastic Bonded Explosives Using 1550 nm Photon Doppler Velocimetry

    Science.gov (United States)

    Gustavsen, R. L.; Bartram, B. D.; Sanchez, N. J.

    2009-12-01

    We present detonation wave profiles measured in two TATB based explosives and two HMX based explosives. Profiles were measured at the interface of the explosive and a Lithium-Fluoride (LiF) window using 1550 nm Photon Doppler Velocimetry (PDV). Planar detonations were produced by impacting the explosive with a projectile launched in a gas-gun. The impact state was changed from shot to shot in order to produce varied distances to detonation. In this way, we tuned the support of the Taylor wave following the Chapman-Jouget (CJ) or sonic state. Profiles from experiments with different support should be the same between the Von-Neumann (VN) spike and CJ state and different thereafter. Comparison of profiles with differing support, therefore, allows us to estimate reaction zone lengths. For the TATB based explosive, a reaction zone length of ≈3.9 mm, 500 ns was measured in EDC-35, and a reaction zone length of ≈6.3 mm, 800 ns was measured in PBX 9502 pre-cooled to -55° C. The respective VN spike state was 2.25±0.05 km/s in EDC-35 and 2.4±0.1 km/s in the cooled PBX 9502. We do not believe we have resolved either the VN spike state (>2.6 km/s) nor the reaction zone length (≪50 ns) in the HMX based explosives.

  2. Molecular Dynamic Simulation for HMX/NTO Supramolecular Explosive

    Institute of Scientific and Technical Information of China (English)

    林鹤; 朱顺官; 张琳; 彭新华; 李洪珍; 陈阳

    2012-01-01

    Based on the crystal engineering, six models of octahydro-1,3 ,5 ,7-tetranitro-1,3 ,5 ,7-tetrazocine ( HMX )/3-nitro-1,2,4-triazol-5-one(NTO) supramolecular explosive were designed. The probable formation of HMX/NTO supramolecular explosive was investigated by the molecular dynamic (MD) method. Interaction between oxygen atoms in HMX and hydrogen atoms in NTO or between hydrogen atoms in HMX and oxygen atoms in NTO were studied by the radial distribution function (RDF). It shows that there are strong hydrogen bonds and Van Der Waals forces between HMX and NTO, in which the hydrogen bonds between oxygen atoms in the NTO and hydrogen atoms in HMX are the main host-guest interactions. The distributions of bond length, bond angle and dihedral angle were simulated by MD. It shows that the structure of HMX is seriously distorted. The binding energies and X-ray powder diffraction (XRD) patterns were calculated on the basis of the final HMX/NTO supramolecular structures. The results show that the binding energies of six supramolecular models are Ebinding (1 1 1) 〉E binding (1 0 0) 〉E binding (0 2 0) 〉E binding (random) 〉Ebinding (1 0 2) 〉 Ebinding(0 1 1), and the XRD patterns of six supramolecular models are quite different from pure HMX or NTO. Based on the investigation for growth morphology, binding energies and RDF, the model of HMX supercell substituted by NTO along the ( 1 1 1 ) surface of HMX is easier to form.

  3. Molecular dynamics simulations of RDX and RDX-based plastic-bonded explosives.

    Science.gov (United States)

    Zhu, Wei; Xiao, Jijun; Zhu, Weihua; Xiao, Heming

    2009-05-30

    Molecular dynamics simulations have been performed to investigate well-known energetic material cyclotrimethylene trinitramine (RDX) crystal and RDX-based plastic-bonded explosives (PBXs) with four typical fluorine-polymers, polyvinylidenedifluoride (PVDF), polychlorotri-fluoroethylene (PCTFE), fluorine rubber (F(2311)), and fluorine resin (F(2314)). The elastic coefficients, mechanical properties, binding energies, and detonation performances are obtained for the RDX crystal and RDX-based PBXs. The results indicate that the mechanical properties of RDX can be effectively improved by blending with a small amount of fluorine polymers and the overall effect of fluorine polymers on the mechanical properties of the PBXs along three crystalline surfaces is (001)>(010) approximately (100) and PVDF is regarded to best improve the mechanical properties of the PBXs on three surfaces. The order of the improvement in the ductibility made by the fluorine polymers on different surfaces is (001) approximately (010)>(100). The average binding energies between different RDX crystalline surfaces and different polymer binders are obtained, and the sequence of the binding energies of the PBXs with the four fluorine polymers on the three different surfaces is varied. Among the polymer binders, PVDF is considered as best one for RDX-based PBXs. The detonation performances of the PBXs decrease in comparison with the pure crystal but are superior to those of TNT.

  4. Effects of temperature and pressure on the glass transitions of plastic bonded explosives

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, M.S.; Garcia, D.; Idar, D.

    1998-12-31

    Various plastic bonded explosives (PBXs) contain about 5-wt% polymer, plasticizer, and stabilizer as binder. The glass-transition temperature (T{sub g}) determines, in part, if the binder will reduce or increase the sensitivity of the PBX to impact. A soft binder reduces the impact sensitivity; however, too soft a binder compromises the mechanical strength below that desirable for dimensional stability. Glass transitions were measured by temperature modulated DSC for PBXs before and after pressing. Pressing temperature was 90 C. The T{sub g} of Estane, a polyester/polyurethane used in some PBX binders, was investigated. Only small changes were observed in the low temperature T{sub g} of the soft segments but larger changes were seen in the higher temperature transitions due to the relaxation of the hard segments. The T{sub g} of Kel F 800, a binder used in insensitive PBX 9502, was observed near ambient temperature. The PBX 9502 had a lower T{sub g} than the neat polymer. Mechanical strength will be measured for the samples.

  5. Implementation of strength and burn models for plastic-bonded explosives and propellants

    Energy Technology Data Exchange (ETDEWEB)

    Reaugh, J E

    2009-05-07

    We have implemented the burn model in LS-DYNA. At present, the damage (porosity and specific surface area) is specified as initial conditions. However, history variables that are used by the strength model are reserved as placeholders for the next major revision, which will be a completely interactive model. We have implemented an improved strength model for explosives based on a model for concrete. The model exhibits peak strength and subsequent strain softening in uniaxial compression. The peak strength increases with increasing strain rate and/or reduced ambient temperature. Under triaxial compression compression, the strength continues to increase (or at least not decrease) with increasing strain. This behaviour is common to both concrete and polymer-bonded explosives (PBX) because the microstructure of these composites is similar. Both have aggregate material with a broad particle size distribution, although the length scale for concrete aggregate is two orders of magnitude larger than for PBX. The (cement or polymer) binder adheres to the aggregate, and is both pressure and rate sensitive. There is a larger bind binder content in concrete, compared to the explosive, and the aggregates have different hardness. As a result we expect the parameter values to differ, but the functional forms to be applicable to both. The models have been fit to data from tests on an AWE explosive that is HMX based. The decision to implement the models in LS-DYNA was based on three factors: LS-DYNA is used routinely by the AWE engineering analysis group and has a broad base of experienced users; models implemented in LS-DYNA can be transferred easily to LLNL's ALE 3D using a material model wrapper developed by Rich Becker; and LS-DYNA could accommodate the model requirements for a significant number of additional history variables without the significant time delay associated with code modification.

  6. Frictional properties of single crystals HMX, RDX and PETN explosives.

    Science.gov (United States)

    Wu, Y Q; Huang, F L

    2010-11-15

    The frictional properties of single crystals of cyclotetramethylene tetranitramine (HMX), cyclotrimethylene trinitramine (RDX) and pentaerythritol tetranitrate (PETN) secondary explosives are examined using a sensitive friction machine. The explosive crystals used for the measurements are at least 3.5 mm wide. The friction coefficients between crystals of the same explosive (i.e., HMX on HMX, etc.), crystals of different explosives (i.e., HMX on RDX, etc.), and each explosive and a well-polished gauge steel surface are determined. The frictional surfaces are also studied under an environmental scanning electron microscope (ESEM) to analyze surface microstructural changes under increasing loading forces. The friction coefficients vary considerably with increasing normal loading forces and are particularly sensitive to slider shapes, crystal roughness and the mechanical properties of both the slider and the sample. With increasing loading forces, most friction experiments show surface damage, consisting of grooves, debris, and nano-particles, on both the slider and sample. In some cases, a strong evidence of a localized molten state is found in the central region of the friction track. Possible mechanisms that affect the friction coefficient are discussed based on microscopic observations. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Friction and impact sensitivities of explosives: A comparative study. [HMX, CP, barium styphnate, RX26BB, RX26BH, PYX, BTF

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Pu Sen; Hall, G.F.

    1988-01-01

    Impact and friction sensitivities of explosives were tested by the ''one-shot'' method. The Bruceton statistical method was used to derive 50% initiation levels. The materials tested include: PETN, HMX, CP, barium styphnate, TATB, RX26BB, RX26BH, PYX, BTF and various types of plastic bonded explosives (PBX). Some samples were investigated for aging effects, physical variables, and the effect of manufacturing parameters on these sensitivities. The results proved to have comparative values. CP and barium styphnate were found to be the most sensitive among the samples tested, while TATB was found to be relatively insensitive. 9 refs., 3 tabs.

  8. Some analytical methods for explosives: Part 2

    Energy Technology Data Exchange (ETDEWEB)

    Selig, W.

    1965-12-08

    This report is the second compilation of methods for analyzing explosives. All the methods were developed for routine performance by techniques, and an attempt has therefore been made to keep them as simple as possible. Methods are presented for analyzing plastic-bonded explosives based on sym-cyclomethylenetetra-nitramine (HMX), based on viton in addition to HMX, and based on pentraerythritol tetranitrate (PETN).

  9. Oblique Plate Impact Experiments to Study the Compression-Shear Behavior of the HMX Based Explosive PBX 9501

    Science.gov (United States)

    Reinhart, William; Gustavsen, Rick; Vogler, Tracy; Alexander, Scott; Thornhill, Tom; Clements, Brad; Bartram, Brian; SNL/LANL Collaboration

    2013-06-01

    HMX (cyclotetramethylene-tetranitramine) based explosive, PBX 9501, is a conventional high explosive formulation composed of 95% wt. of HMX and 5% binders. A series of experiments were performed to investigate one-dimensional combined pressure-shear waves in PBX-9501. This study is thought to be the first to estimate shear stress and strength in a plastic bonded high explosive. Experiments were conducted using Sandia National Laboratories oblique launcher at the Shock Thermodynamics Applied Research (STAR) facility. A projectile is keyed to a slot in the launcher barrel in order to prevent rotation. The projectile is faced with a titanium alloy plate inclined at 20 degrees to the launcher axis. The target consists of a 1 mm thick PBX 9501 disk sandwiched between two titanium alloy plates. Measurements of shear and longitudinal particle velocities were used to determine stresses and infer strength. Longitudinal stresses from 1.4 to 3.1 GPa were applied which presented corresponding shear stresses of 0.1 to 0.23 GPa at high shearing strain rates up to 0.4 x 105s-1. This experimental data now provides for the first time, relevant information for model development.

  10. Experimental Study of the Impact Damage of Composition B and Plastic Bonded Explosive

    Institute of Scientific and Technical Information of China (English)

    陈鹏万; 黄风雷; 丁雁生

    2003-01-01

    A long-pulse low-velocity gas gun with a gas buffer is used to induce impact damage in cast Composition B and hot pressed PBXN-5. To obtain different damage states, a range of projectile velocities are used by controlling the launching pressure of gas gun. The stress history during impact loading is recorded. Various methods are used to characterize the damage state of impacted explosive samples. The microstructure is examined by use of scanning electronic microscopy (SEM) and polarized light microscopy (PLM). The densities and ultrasonic attenuation are also measured. The results show that both Composition B and PBXN-5 exhibit some damage characteristics of brittle materials. However, due to the difference in compositions, PBXN-5 exhibits better resistance to impact loading than Composition B.

  11. ESTIMATIVA DE VIDA ÚTIL DO PBX (plastic-bonded explosive COM ENVELHECIMENTO ACELERADO

    Directory of Open Access Journals (Sweden)

    Edemar Kirchhof

    2016-07-01

    Full Text Available This article aims to estimate the shelf life of the PBX by thermal analysis estimated by the Arrhenius equation, equivalent to the time of storage at accelerated aging. The PBX was subjected to accelerated aging in an oven at controlled temperature 60 ºC for periods of 5, 10, 15 and 25 weeks, which are equivalent to 5, 10, 15 and 25 of natural aging, respectively, at a temperature of 25 ºC. The curves of thermal decomposition of the samples were obtained by the DSC (Differential Scanning Calorimetry technique. The kinetic parameters, such as the activation energy and pre-exponential factor, were determined by the Ozawa method and the Kissinger method. Initial results of this study indicated that, for a period of 25 years of storage in the cargo hold, the material did not change this aging significantly. To study the life of PBX analyzes, vacuum chemical stability were also conducted to verify the safety of explosive handling.

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

    Directory of Open Access Journals (Sweden)

    Chongwei An

    2017-01-01

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

  13. Influence of Small Change of Porosity on Shock Initiation of an HMX/TATB/Viton Explosive and Ignition and Growth Modeling

    Science.gov (United States)

    Liu, Yan; Hussain, Tariq; Huang, Fenglei; Duan, Zhuoping

    2016-07-01

    All solid explosives in practical use are more or less porous. Although it is known that the change in porosity affects the shock sensitivity of solid explosives, the effect of small changes in porosity on the sensitivity needs to be determined for safe and efficient use of explosive materials. In this study, the influence of a small change in porosity on shock initiation and the subsequent detonation growth process of a plastic-bonded explosive PBXC03, composed of 87% cyclotetramethylene-tetranitramine (HMX), 7% triaminotrinitrobenzene (TATB), and 6% Viton by weight, are investigated by shock to detonation transition experiments. Two explosive formulations of PBXC03 having the same initial grain sizes pressed to 98 and 99% of theoretical mass density (1.873 g/cm3) respectively are tested using the in situ manganin piezoresistive pressure gauge technique. Numerical modeling of the experiments is performed using an ignition and growth reactive flow model. Reasonable agreement with the experimental results is obtained by increasing the growth term coefficient in the Lee-Tarver ignition and growth model with porosity. Combining the experimental and simulation results shows that the shock sensitivity increases with porosity for PBXC03 having the same explosive initial grain sizes for the pressures (about 3.1 GPa) applied in the experiments.

  14. Experimental and numerical study of deformation modes of a pressed HMX-based explosive composition

    Science.gov (United States)

    Picart, Didier; Vial, Jerome; Bailly, Patrice

    Safety of industrial or military explosives is still studied to prevent inadvertent ignition of pressed HMX-based explosive compositions submitted to a low-velocity impact. Our aim is to determine the dissipative mechanisms leading to the local heating of the material. To observe the dissipative mechanisms, a reversed edge-on impact test has been developed. This test enables real-time observations of the microstructural scale. No friction is observed between the biggest HMX grains and the matrix (the smallest grains, the binder and the porosity). Plasticity of HMX grains is obtained as well as damage by micro-cracking. Meanwhile, a biphasic numerical representation (HMX grains and matrix) is used to mimic our material. A comparison between experimental observations and simulations is used to determine the yield stress of HMX. The behavior of the matrix has been determined to account for the effect of strain rate and damage. Lastly, a comparison between tests and simulations has highlighted (1) that heating should rather be located in the matrix than in the biggest HMX grains and (2) that the most likely heating mechanism is the friction of micro(or meso)-cracks lips.

  15. Thermal Explosion Violence of HMX-Based and RDX-Based Explosives - Effects of Composition, Confinement, and Solid Phase Using the Scaled Thermal Explosion Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Maienschein, J L; Wardell, J F

    2002-08-26

    The Scaled Thermal Explosion Experiment (STEX) has been developed to quantify the violence of thermal explosion under well defined and carefully controlled initial and boundary conditions. Here we present results with HMX-based explosives (LX-04 and PBX-9501) and with Composition B. Samples are 2 inches (50 mm) in diameter and 8 inches (200 mm) in length, under confinement of 7,500-30,000 psi (50-200 MPa), with heating rates of 1-3 C/hr. We quantify reaction violence by measuring the wall velocity in the ensuing thermal explosion, and relate the measured velocity to that expected from a detonation. Results with HMX-based explosives (LX-04 and PBX-9501) have shown the importance of confinement and HMX solid phase, with reaction violence ranging from mild pressure bursts to near detonations. By contrast, Composition B has shown very violent reactions over a wide range of conditions.

  16. Thermal Explosion Violence of HMX-Based and RDX-Based Explosives - Effects of Composition, Confinement, and Solid Phase Using the Scaled Thermal Explosion Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Maienschein, J L; Wardell, J F

    2002-03-14

    The Scaled Thermal Explosion Experiment (STEX) has been developed to quantify the violence of thermal explosion under well defined and carefully controlled initial and boundary conditions. Here we present results with HMX-based explosives (LX-04 and PBX-9501) and with Composition B. Samples are 2 inches (50 mm) in diameter and 8 inches (200 mm) in length, under confinement of 7,500-30,000 psi (50-200 MPa), with heating rates of 1-3 C/hr. We quantify reaction violence by measuring the wall velocity in the ensuing thermal explosion, and relate the measured velocity to that expected from a detonation. Results with HMX-based explosives (LX-04 and PBX-9501) have shown the importance of confinement and HMX solid phase, with reaction violence ranging from mild pressure bursts to near detonations. By contrast, Composition B has shown very violent reactions over a wide range of conditions.

  17. Trace Detection of RDX, HMX and PETN Explosives Using a Fluorescence Spot Sensor

    Science.gov (United States)

    Wang, Chen; Huang, Helin; Bunes, Benjamin R.; Wu, Na; Xu, Miao; Yang, Xiaomei; Yu, Li; Zang, Ling

    2016-05-01

    1,3,5-trinitroperhydro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and pentaerythritol tetranitrate (PETN), the major components in plastic explosives, pose a significant threat to public safety. A quick, sensitive, and low-cost detection method for these non-volatile explosives is eagerly demanded. Here we present a fluo-spot approach, which can be employed for in situ detection of trace amount of explosives. The sensor molecule is a charge-transfer fluorophore, DCM, which is strongly fluorescent in its pristine state, but non-fluorescent after the quick reaction with NO2· (or NO2+) generated from the UV photolysis of RDX, HMX (or PETN). When fabricated within silica gel TLC plate, the fluo-spot sensor features high sensitivity owing to the large surface area and porous structure of the substrate. The sensor reaction mechanism was verified by various experimental characterizations, including chromatography, UV-Vis absorption and fluorescence spectroscopy, MS and 1H NMR spectrometry. The fluo-spot also demonstrated high selectivity towards RDX, HMX and PETN, as no significant fluorescence quenching was observed for other chemical compounds including common nitro-aromatic explosives and inorganic oxidative compounds. The DCM sensor can also be used as an economical spray kit to directly spot the explosives by naked eyes, implying great potential for quick, low-cost trace explosives detection.

  18. A Survey on the Cyclotetramethylene Tetranitramine (HMX

    Directory of Open Access Journals (Sweden)

    Balwant Singh

    1978-01-01

    Full Text Available Cyclotetramethylene tetranitramine (1,3,5,7,-tetranitro-1,3,5,7,-tetrazacyclo-octane which has been classified as high explosive, a source of high chemical energy, falls into polynitramine group of the nitramines. Its is also known as octogen and HMX. Its is one of the most powerful explosives having high density(1.9g/cc, high melting point (281 Degree calcius and high velocity of detonation(9100m/sec. It has slightly higher energy than RDX and therefore, used where a maximum energy is required by limited dimensions of charge. Because of its resistance towards heat, it has become the nucleus of research for thermally for thermally stable compositions. It has been used in number of binary mixtures in conjunction with TNT, RDX,TNB etc. It forms the main constituent in certain plastic bonded explosives(PBX. In the present review attempt has been made to cover the available literature on HMX.

  19. Reflection terahertz time-domain spectroscopy of RDX and HMX explosives

    Science.gov (United States)

    Choi, Kyujin; Hong, Taeyoon; Ik Sim, Kyung; Ha, Taewoo; Cheol Park, Byung; Hyuk Chung, Jin; Gyeong Cho, Soo; Hoon Kim, Jae

    2014-01-01

    We report on our study of RDX and HMX, two of the most commonly used explosive materials, in bulk pellets with reflection terahertz time-domain spectroscopy in the frequency range of 0.3-3 THz. The maximum entropy method was utilized to correct our raw reflection data against the phase error due to the relative displacement between the sample and the reference. Both the refractive index n and the extinction coefficient k in the terahertz region were acquired for these two explosives without a Kramers-Kronig analysis. Both RDX and HMX exhibit a series of distinct peaks not quite detectable in the more conventional transmission-type measurements due to their high terahertz absorptivity. Our results are compared with the literature data on powder samples.

  20. One-dimensional plate impact experiments on the cyclotetramethylene tetranitramine (HMX) based explosive EDC32

    Science.gov (United States)

    Burns, Malcolm J.; Gustavsen, Richard L.; Bartram, Brian D.

    2012-09-01

    Eight one-dimensional plate impact experiments have been performed to study both the Shock to Detonation Transition and Hugoniot state in the cyclotetramethylene tetranitramine (HMX) based explosive EDC32. The experiments covered shock pressures ranging from 0.59 to 7.5 GPa with sustained shocks, double shocks, and short pulse shocks. Experiments were instrumented with embedded magnetic particle velocity gauges. Results include; (1) wave profiles of particle velocity vs. time vs. depth in the explosive, (2) time-distance coordinates for onset of detonation vs. initial shock pressure (aka the Pop-plot), (3) a reactants Hugoniot, and (4) measurement of the Hugoniot Elastic Limit of 0.22.GPa.

  1. Base hydrolysis kinetics of HMX-based explosives using sodium carbonate

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, R.L.; Skidmore, C.; Flesner, R.L.; Dell`orco, P.C.; Spontarelli, T.; Uher, K.J.; Kramer, J.F. [Los Alamos National Lab., NM (United States); Bell, D.A. [Wyoming Univ., Laramie, WY (United States)

    1996-07-01

    Sodium carbonate has been identified as a possible hydrolysis reagent for decomposing HMX-based explosives to water soluble, non-energetic products. In this study, the reaction kinetics of sodium carbonate hydrolysis are examined and a reaction model is developed. The rate of hydrolysis is reaction rate limited, opposed to mass transfer limited, up to 150{degrees}C. Greater than 99% of the explosive solids in powder form are destroyed in less than 10 minutes at a temperature of 150{degrees}C. The primary products from sodium carbonate hydrolysis are sodium nitrite, formate, nitrate, acetate, glycolate, hexamine, nitrogen gas, nitrous oxide, and ammonia.

  2. Binder/HMX interaction in PBX9501 at Elevated Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    K., S C; M., T C

    2003-10-02

    Plastic bonded explosives (PBX) generally consist of 85 - 95 % by weight energetic material, such as HMX, and 5 - 15 % polymeric binder. Understanding of the structure and morphology at elevated temperatures and pressures is important for predicting of PBX behavior in accident scenarios. The crystallographic behavior of pure HMX has been measured as functions of temperature and grain size. The investigation is extended to the high temperature behavior of PBX 9501 (95% HMX, 2.5 % Estane, 2.5 % BDNPA/F). The results show that the HMX {beta}-phase to {delta}-phase transition in PBX 9501 is similar to that in neat HMX. However, in the presence of the PBX 9501 binder, {delta}-phase HMX readily converts back to {beta}-phase during cooling. Using the same temperature profile, the conversion rate decreases for each subsequent heating and cooling cycle. As observed in earlier experiments, no reverse conversion is observed without the polymer binder. It is proposed that the reversion of {delta}-phase to {beta}-phase is due to changes in the surface molecular potential caused by the influence of the polymer binder on the surface molecules of the {delta}-phase. Upon thermal cycling, the polymer binder segregates from the HMX particles and thus reduces the influence of the binder on the surface molecules. This segregation increases the resistance for the {delta}-phase to {beta}-phase transition, as demonstrated in an aged PBX 9501 material for which the reversion is not observed.

  3. Thermal Cook-off of an HMX Based Explosive: Pressure Gauge Experiments and Modeling

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-04-02

    Safety issues related to thermal cook-off are important for handling and storing explosive devices. Violence of event as a function of confinement is important for prediction of collateral events. There are major issues, which require an understanding of the following events: (1) transit to detonation of a pressure wave from a cook-off event, (2) sensitivity of HMX based explosives changes with thermally induced phase transitions and (3) the potential danger of neighboring explosive devices being affected by a cook-off reaction. Results of cook-off events of known size, confinement and thermal history allows for development and/or calibrating computer models for calculating events that are difficult to measure experimentally.

  4. Determination of sound velocities of "overcompressed" detonation in HMX-based explosive

    Science.gov (United States)

    Zhernokletov, Mikhail V.; Kovalev, Alexey E.; Bel'sky, Vladimir M.; Bogdanov, Evgeny N.

    2015-09-01

    The authors present results of determination of sound velocities in explosion products (EP) of HMX-based explosive overcompressed up to the pressures of 50-85 GPa by overtaking unloading method. The radiowave and optical methods are used to record the time when a front of overcompressed detonation wave in investigated sample of high explosive (HE) is overtaken by expansion wave, which propagates from the back surface of impactor with sound velocity. The data on sound velocities, which were independently obtained by two different methods, were in agreement. The methods with use of radiointerferometer and indicator liquid are rather effective for determination of sound velocities in overcompresed EP and for investigation of parameters at the Jouget point of various HEs, which are required for calibration of their equations of state (EOS).

  5. Determination of sound velocities of “overcompressed” detonation in HMX-based explosive

    Directory of Open Access Journals (Sweden)

    Zhernokletov Mikhail V.

    2015-01-01

    Full Text Available The authors present results of determination of sound velocities in explosion products (EP of HMX-based explosive overcompressed up to the pressures of 50–85 GPa by overtaking unloading method. The radiowave and optical methods are used to record the time when a front of overcompressed detonation wave in investigated sample of high explosive (HE is overtaken by expansion wave, which propagates from the back surface of impactor with sound velocity. The data on sound velocities, which were independently obtained by two different methods, were in agreement. The methods with use of radiointerferometer and indicator liquid are rather effective for determination of sound velocities in overcompresed EP and for investigation of parameters at the Jouget point of various HEs, which are required for calibration of their equations of state (EOS.

  6. Shock Induced Shear Strength in Two HMX Based Polymer Bonded Explosives

    Science.gov (United States)

    Millett, Jeremy; Taylor, Peter; Appleby-Thomas, Gareth

    2015-06-01

    The response of energetic materials to shock loading has largely concentrated on their detonation behaviour. However, they can also be considered to be structural materials in their own right, and hence their response to a purely mechanical shock loading is also of interest. Therefore we present results from two HMX based polymer bonded explosives, EDC37 and EDC32, where we investigate the shock induced shear strength behind the shock front. Results are discussed in terms of microstructure and differences of the binder phases.

  7. Equations of state of unreacted explosives: PETN, RDX, HMX, TATB

    Directory of Open Access Journals (Sweden)

    Nadykto B.A.

    2011-01-01

    Full Text Available For most of explosive conversion kinetics simulations associated with the analysis of HE initiation, safety of HE handling, accidents, etc., one needs to know the equation of state of yet unreacted (“cold” HE. Acquisition of experimental data for such materials poses a real challenge, such data are rather scarce, and their accuracy does not allow plotting continuous curves at all times. In this case, computational, theoretical and semi-empirical approaches that involve a limited number of available experimental points can provide a more detailed description of HE behavior.

  8. NPT Ensemble MD Simulation Investigation on the Mechanical Properties of HMX/F2311 Polymer-bonded Explosive

    Institute of Scientific and Technical Information of China (English)

    XIAO Ji-Jun; ZHANG Hang; HUANG Hui; LI Jing-Shang; ZHU Wei; XIAO He-Ming

    2008-01-01

    Molecular dynamics simulation was applied to investigate the mechanical properties of β-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(β-HMX)-based polymer-bonded explosive(PBX)with F2311 fluorine rubber(It is produced by copolymerization of vinylidene difluoride and chlorotrifluoroethylene in the molar ratio 1 over 1).The elastic constants for β-HMX crystal and the HMX-based PBX were computed using a static elastic constant analysis method,and the engineering moduli and Poisson ratios were derived by Reuss average.Based on the value of Cauchy pressure and the ratio of bulk modulus to shear modulus,it is indicated that the ductibility of crystalline HMX can be effectively improved by blending the polymer in a small amount.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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. Ignition and growth modeling of detonation reaction zone experiments on single crystals of PETN and HMX

    Science.gov (United States)

    White, Bradley W.; Tarver, Craig M.

    2017-01-01

    It has long been known that detonating single crystals of solid explosives have much larger failure diameters than those of heterogeneous charges of the same explosive pressed or cast to 98 - 99% theoretical maximum density (TMD). In 1957, Holland et al. demonstrated that PETN single crystals have failure diameters of about 8 mm, whereas heterogeneous PETN charges have failure diameters of less than 0.5 mm. Recently, Fedorov et al. quantitatively determined nanosecond time resolved detonation reaction zone profiles of single crystals of PETN and HMX by measuring the interface particle velocity histories of the detonating crystals and LiF windows using a PDV system. The measured reaction zone time durations for PETN and HMX single crystal detonations were approximately 100 and 260 nanoseconds, respectively. These experiments provided the necessary data to develop Ignition and Growth (I&G) reactive flow model parameters for the single crystal detonation reaction zones. Using these parameters, the calculated unconfined failure diameter of a PETN single crystal was 7.5 +/- 0.5 mm, close to the 8 mm experimental value. The calculated failure diameter of an unconfined HMX single crystal was 15 +/- 1 mm. The unconfined failure diameter of an HMX single crystal has not yet been determined precisely, but Fedorov et al. detonated 14 mm diameter crystals confined by detonating a HMX-based plastic bonded explosive (PBX) without initially overdriving the HMX crystals.

  12. Preparation of Insensitive Composite Explosives HMX/TATB Using Ultrasonic Method%原位合成钝感混合炸药HMX/TATB

    Institute of Scientific and Technical Information of China (English)

    黄凤臣; 邓明哲

    2011-01-01

    The TATB was prepared by ultrasonic wave. The insensitive composite explosives HMX/TATB was prepared in a reactor with high frequency ultrasonic wave by the in situ synthetic method. The effect of reaction time, temperature and the ratio of raw materials on synthetic yield of TATB was discussed. The shaping and heat resistance of the composite explosives were investigated. The results show that the TATB grained sizes by the ultrasonic wave synthetic method were from 5 to 6 μm, the mass fraction of TATB in the composite explosives was less than 15%, so the effect of reduced sensitivity and the heat resistance were good. The shaping of the composite explosives using the fluorine rubber FPM264 as an adhesive was excellent.%利用超声波法制备单质炸药TATB,用高频率超声波反应器,采用原位合成方法制备了钝感HMX/TATB混合炸药.讨论了反应时间、反应温度以及料比对合成TATB的影响.测试了混合炸药的压制成型性和耐热性能.结果表明,超声波法合成的TATB粒度为5~6μm,混合炸药中TATB的质量分数小于15%,降感效果明显,耐热性能良好;使用氟橡胶FPM246作黏结剂,混合药的压制成型性优良.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. Theoretical insights into the effects of molar ratios on stabilities, mechanical properties, and detonation performance of CL-20/HMX cocrystal explosives by molecular dynamics simulation.

    Science.gov (United States)

    Hang, Gui-Yun; Yu, Wen-Li; Wang, Tao; Wang, Jin-Tao; Li, Zhen

    2017-01-01

    To research and estimate the effects of molar ratios on structures, stabilities, mechanical properties, and detonation properties of CL-20/HMX cocrystal explosive, the CL-20/HMX cocrystal explosive models with different molar ratios were established in Materials Studio (MS). The crystal parameters, structures, stabilities, mechanical properties, and some detonation parameters of different cocrystal explosives were obtained and compared. The molecular dynamics (MD) simulation results illustrate that the molar ratios of CL-20/HMX have a direct influence on the comprehensive performance of cocrystal explosive. The hardness and rigidity of the 1:1 cocrystal explosive was the poorest, while the plastic property and ductibility were the best, thus implying that the explosive has the best mechanical properties. Besides, it has the highest binding energy, so the stability and compatibility is the best. The cocrystal explosive has better detonation performance than HMX. In a word, the 1:1 cocrystal explosive is worth more attention and further research. This paper could offer some theoretical instructions and technological support, which could help in the design of the CL-20 cocrystal explosive.

  16. Equation of state formulation for unreacted solid high explosives, PETN and HMX

    Science.gov (United States)

    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).

  17. Understanding and Predicting the Thermal Explosion Violence of HMX-Based and RDX-Based Explosives - Experimental Measurements of Material Properties and Reaction Violence

    Energy Technology Data Exchange (ETDEWEB)

    Maienschein, J L; Wardell, J F; Weese, R K; Cunningham, B J; Tran, T D

    2002-07-03

    The violence of thermal explosions with energetic materials is affected by many material properties, including mechanical and thermal properties, thermal ignition kinetics, and deflagration behavior. These properties must be characterized for heated samples as well as pristine materials. We present available data for these properties for two HMX-based formulations--LX-04 and PBX-9501, and two RDX-based formulations--Composition B and PBXN-109. We draw upon separately published data on the thermal explosion violence with these materials to compare the material properties with the observed violence. We have the most extensive data on deflagration behavior of these four formulations, and we discuss the correlation of the deflagration data with the violence results. The data reported here may also be used to develop models for application in simulation codes such as ALE3D to calculate and Dredict thermal explosion violence.

  18. Mechanical and microstructural characterization of a HMX-based pressed explosive: Effects of combined high pressure and strain rate

    Directory of Open Access Journals (Sweden)

    Biessy M.

    2012-08-01

    Full Text Available The paper presents a study of the combined effects of strain rate and confining pressure on the behaviour and microstructure evolutions of a HMX-based explosive. Hopkinson bar compression experiments are carried-out on samples confined with a brass sleeve. The latter is instrumented in order to determine the confining pressure on the explosive sample, directly function of the sleeve thickness and yield strength. A sample confined at 75 MPa and deformed at 250s−1 is recovered, cross-sectioned and studied using optical microscopy. Distributed microplasticity and microcracking appear similar to those induced by confined quasi-static experiments, indicating that stress triaxiality is the most important loading parameter. The sample also displays a large shear macrocrack, resulting from the formation of an adiabatic shear band. Shear banding seems to proceed by strong plastic strain gradients, followed by dynamic re-crystallization. Further strong thermal effects are observed, resulting in local reactive melting.

  19. Shock Sensitivity of LX-04 Containing Delta Phase HMX at Elevated Temperatures

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-11

    LX-04 is a widely used HMX-based plastic bonded explosive, which contains 85 weight % HMX and 15 weight % Viton binder. The sensitivity of LX-04 to a single stimulus such as heat, impact, and shock has been previously studied. However, hazard scenarios can involve multiple stimuli, such as heating to temperatures close to thermal explosion conditions followed by fragment impact, producing a shock in the hot explosive. The sensitivity of HMX at elevated temperatures is further complicated by the beta to delta solid-state phase transition, which occurs at approximately 165 C. This paper presents the results of shock initiation experiments conducted with LX-04 preheated to 190 C, as well as density measurements and small scale safety test results of the {delta} phase HMX at room temperature. This work shows that LX-04 at 190 C is more shock sensitive than LX-04 at 150 C or 170 C due to the volume increase during the {beta} to {delta} solid phase transition, which creates more hot spots, and the faster growth of reaction during shock compression.

  20. Experimental and TD-DFT study of optical absorption of six explosive molecules: RDX, HMX, PETN, TNT, TATP, and HMTD.

    Science.gov (United States)

    Cooper, Jason K; Grant, Christian D; Zhang, Jin Z

    2013-07-25

    Time dependent density function theory (TD-DFT) has been utilized to calculate the excitation energies and oscillator strengths of six common explosives: RDX (1,3,5-trinitroperhydro-1,3,5-triazine), β-HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), TATP (triacetone triperoxide), HMTD (hexamethylene triperoxide diamine), TNT (2,4,6-trinitrotoluene), and PETN (pentaerythritol tetranitrate). The results were compared to experimental UV-vis absorption spectra collected in acetonitrile. Four computational methods were tested including: B3LYP, CAM-B3LYP, ωB97XD, and PBE0. PBE0 outperforms the other methods tested. Basis set effects on the electronic energies and oscillator strengths were evaluated with 6-31G(d), 6-31+G(d), 6-31+G(d,p), and 6-311+G(d,p). The minimal basis set required was 6-31+G(d); however, additional calculations were performed with 6-311+G(d,p). For each molecule studied, the natural transition orbitals (NTOs) were reported for the most prominent singlet excitations. The TD-DFT results have been combined with the IPv calculated by CBS-QB3 to construct energy level diagrams for the six compounds. The results suggest optimization approaches for fluorescence based detection methods for these explosives by guiding materials selections for optimal band alignment between fluorescent probe and explosive analyte. Also, the role of the TNT Meisenheimer complex formation and the resulting electronic structure thereof on of the quenching mechanism of II-VI semiconductors is discussed.

  1. Sensitivity of once-shocked, weathered high explosives

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Pressure Wave Measurements from Thermal Cook-off of an HMX Based Explosive

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-05-09

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Mesoscale evolution of voids and microstructural changes in HMX-based explosives during heating through the β-δ phase transition

    Science.gov (United States)

    Willey, Trevor M.; Lauderbach, Lisa; Gagliardi, Franco; van Buuren, Tony; Glascoe, Elizabeth A.; Tringe, Joseph W.; Lee, Jonathan R. I.; Springer, H. Keo; Ilavsky, Jan

    2015-08-01

    HMX-based explosives LX-10 and PBX-9501 were heated through the β-δ phase transition. Ultra-small angle x-ray scattering (USAXS) and molecular diffraction were simultaneously recorded as the HMX was heated. Mesoscale voids and structure dramatically change promptly with the β-δ phase transition, rather than with other thermal effects. Also, x-ray induced damage, observed in the USAXS, occurs more readily at elevated temperatures; as such, the dose was reduced to mitigate this effect. Optical microscopy performed during a similar heating cycle gives an indication of changes on longer length scales, while x-ray microtomography, performed before and after heating, shows the character of extensive microstructural damage resulting from the temperature cycle and solid-state phase transition.

  6. Mesoscale evolution of voids and microstructural changes in HMX-based explosives during heating through the β-δ phase transition

    Energy Technology Data Exchange (ETDEWEB)

    Willey, Trevor M., E-mail: willey1@llnl.gov; Lauderbach, Lisa; Gagliardi, Franco; Buuren, Tony van; Glascoe, Elizabeth A.; Tringe, Joseph W.; Lee, Jonathan R. I.; Springer, H. Keo [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Ilavsky, Jan [Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2015-08-07

    HMX-based explosives LX-10 and PBX-9501 were heated through the β-δ phase transition. Ultra-small angle x-ray scattering (USAXS) and molecular diffraction were simultaneously recorded as the HMX was heated. Mesoscale voids and structure dramatically change promptly with the β-δ phase transition, rather than with other thermal effects. Also, x-ray induced damage, observed in the USAXS, occurs more readily at elevated temperatures; as such, the dose was reduced to mitigate this effect. Optical microscopy performed during a similar heating cycle gives an indication of changes on longer length scales, while x-ray microtomography, performed before and after heating, shows the character of extensive microstructural damage resulting from the temperature cycle and solid-state phase transition.

  7. Study on the Aging Effect on the Explosion Heat and Detonation Velocity of HMX/RDX Based Aluminized Explosive%老化对HMX/RDX基含铝炸药爆热及爆速性能的影响研究

    Institute of Scientific and Technical Information of China (English)

    黄亚峰; 赵省向; 李文祥; 杨建刚; 李欣; 刘文亮

    2013-01-01

      为了研究老化对HMX/RDX基含铝炸药的性能影响,在71℃下对组成为65(HMX/RDX)/30Al/5粘结剂的含铝炸药老化55d,然后测试炸药的爆热与爆速。试验结果表明:药柱体积随着老化时间的增长呈现先变大后缩小的趋势,质量随着老化时间的增长呈现逐渐减小的趋势,但变化率都在0.1%内;爆热和爆速随着老化时间的增长几乎没有变化。%  In order to investigate the aging effect on the performance of the HMX/RDX based aluminized explosive, the aluminized explosive of (HMX/RDX)/Al/ binder-65/30/5 was aged 55 days at 71℃, then the explosion heat and detonation velocity were tested. The aging results show that the charge bulk has a trend of first increase and then decrease with the increase of aging time, and the charge weight has a trend of decrease with the increase of aging time, but the change rate of bulk and weight was in 0.1%. The explosion heat and detonation velocity changed little with the increase of aging time.

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

    Directory of Open Access Journals (Sweden)

    Jie Liu

    2014-06-01

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

  9. A global HMX decomposition model

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, M.L.

    1996-12-01

    HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) decomposes by competing reaction pathways to form various condensed and gas-phase intermediate and final products. Gas formation is related to the development of nonuniform porosity and high specific surface areas prior to ignition in cookoff events. Such thermal damage enhances shock sensitivity and favors self-supported accelerated burning. The extent of HMX decomposition in highly confined cookoff experiments remains a major unsolved experimental and modeling problem. The present work is directed at determination of global HMX kinetics useful for predicting the elapsed time to thermal runaway (ignition) and the extent of decomposition at ignition. Kinetic rate constants for a six step engineering based global mechanism were obtained using gas formation rates measured by Behrens at Sandia National Laboratories with his Simultaneous Modulated Beam Mass Spectrometer (STMBMS) experimental apparatus. The six step global mechanism includes competition between light gas (H[sub 2]Awe, HCN, CO, H[sub 2]CO, NO, N[sub 2]Awe) and heavy gas (C[sub 2]H[sub 6]N[sub 2]Awe and C[sub 4]H[sub 10]N0[sub 2]) formation with zero order sublimation of HMX and the mononitroso analog of HMX (mn-HMX), C[sub 4]H[sub 8]N[sub 8]Awe[sub 7]. The global mechanism was applied to the highly confined, One Dimensional Time to eXplosion (ODTX) experiment and hot cell experiments by suppressing the sublimation of HMX and mn-HMX. An additional gas-phase reaction was also included to account for the gas-phase reaction of N[sub 2]Awe with H[sub 2]CO. Predictions compare adequately to the STMBMS data, ODTX data, and hot cell data. Deficiencies in the model and future directions are discussed.

  10. HMX/NQ 共晶分子间相互作用的密度泛函理论研究%Study on the Intermolecular Interaction of HMX/NQ Cocrystal Explosive by Density Functional Theory

    Institute of Scientific and Technical Information of China (English)

    杨文升; 苟瑞君; 张树海; 丁雄; 武学; 刘平; 林文禄

    2015-01-01

    To investigate the intermolecular interactions of HMX with high sensitivity/NQ with low sensitivity cocrystal, the structures of four kinds of HMX/NQ cocrystals I,II,III and IV in the text were studied using a density functional theory (DFT).The intermolecular interaction of four kinds of structures of HMX/NQ cocrystal and the properties of the explosive were analyzed and predicted using electrostatic potential,electron density topological,reduced density gradient and trigger bond etc methods.The results show that the nature of the intermolecular interactions of HMX/NQ cocrystal is interactions of a series of weak hydrogen bond and Van der Waals force,involving the interactions of NH…O,CH…O and O…N.The interaction energy of four kinds of configuration bonds decreases in the order of structureIII>struc-tureII≈structureIV>structureI.Compared with HMX and NQ,the trigger bond strength increases,the stability enhances and the sensitivity decreases for HMX/NQ cocrystal and the performance of structure III is more obvious.%为研究 HMX/NQ 共晶分子间的相互作用,基于密度泛函理论(DFT)研究了4种 HMX/NQ 的共晶结构;运用静电势、电子密度拓扑、约化密度梯度和引发键等方法分析和预测了其分子间的相互作用和炸药性质。结果表明,HMX/NQ 共晶的分子间作用本质是一系列弱氢键和范德华力的共同作用,主要表现为 NH…O、CH…O 和N…O 作用;4种构型键的相互作用能大小排序为结构 III>结构 II≈结构 IV>结构 I;与 HMX 和 NQ 相比,HMX/NQ 共晶的引发键强度增大,稳定性增强,感度降低,结构 III 的表现较为明显。

  11. Theoretical Insight into the Influences of Molecular Ratios on Stabilities and Mechanical Properties, Solvent Effect of HMX/FOX-7 Cocrystal Explosive

    Science.gov (United States)

    Wei, Yan-Ju; Ren, Fu-De; Shi, Wen-Jing; Zhao, Qi

    2016-10-01

    A molecular dynamics method was employed to study the binding energies of the selected crystal planes of the 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane/1,1-diamino-2,2-dinitroethylene (HMX/FOX-7) cocrystal in different molecular molar ratios. Mechanical properties, densities, and detonation velocities of the cocrystals in different ratios were estimated. The intermolecular interactions and bond dissociation energies (BDEs) of the N-NO2 bond in the HMX:FOX-7 (1:1) complex were calculated using the B3LYP and MP2(full) methods at the 6-311++G (d,p) and 6-311++G(2df,2p) basis sets. Solvent effects on stability are discussed. The results indicate that HMX/FOX-7 cocrystals prefer cocrystalizing in a 1:1 molar ratio, which has good mechanical properties. The N-NO2 bond becomes strong upon the formation of a complex and the sensitivity of HMX might decrease in cocrystals. The sensitivity change of HMX/FOX-7 originates from not only the formation of intermolecular interaction but also the increment in the N-NO2 BDE. HMX/FOX-7 cocrystals exhibit good detonation performance and meet the requirements of high-density energetic materials. Solvents with low dielectric constants may be chosen to obtain stable HMX/FOX-7 cocrystals.

  12. Treatment of HMX and RDX contamination

    Energy Technology Data Exchange (ETDEWEB)

    Card, R.E. Jr.; Autenrieth, R. [Texas A& M Univ., College Station, TX (United States)

    1998-03-01

    HMX and RDX are often found in the soil, groundwater, and surface waters at facilities where they are manufactured as the result of negligent disposal methods. The toxicity of these compounds and their degradation products has led to concern about their fate in the environment and the potential for human exposure. HMX and RDX are recalcitrant in the environment with low rates of biodegradation and photolysis. Several methods of treating contaminated soils and waters have been developed and studied. Many of these technologies (i.e., carbon adsorption, oxidation, and chemical treatment) have been developed to treat munition plant wastewaters that are contaminated with explosives. These methods need to be adapted to remediate contaminated water. Other technologies such as bioremediation and composting are being developed as methods of remediating HMX and RDX contamination in a solid matrix. This report describes and evaluates each of these technologies. This report also describes the processes which affect HMX and RDX in the environment. The major transformation processes of RDX and HMX in the environment are biodegradation and photolysis. A major factor affecting the transport and treatment of RDX and HMX in soil-water environments is their sorption and desorption to soil particles. Finally, this report draws conclusions as to which treatment methods are currently most suitable for the remediation of contaminated soils and waters.

  13. Preparation and Properties of Surface-Coated HMX with Viton and Graphene Oxide

    Science.gov (United States)

    Wang, Jingyu; Ye, Baoyun; An, Chongwei; Wu, Bidong; Li, Hequn; Wei, Yanju

    2016-07-01

    To improve the safety performance of HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) particles, the new carbon material graphene oxide (GO) and Viton were used to coat HMX via a solvent-slurry process. For comparison, the HMX/Viton/graphite (HMX/Viton/G) and HMX/Viton composites were also prepared by the same process. Atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and differential scanning calorimetry (DSC) were employed to characterize the morphology, composition, and thermal decomposition of samples. The impact sensitivity and shock wave sensitivity of HMX-based composites were also measured and analyzed. The results of SEM, XRD, and XPS indicate that the cladding layer of HMX-based composites is successfully constructed. HMX/Viton/GO composites exhibit better thermal stability compared to HMX and HMX/Viton. The results show that both impact and shock wave sensitivities of HMX/Viton/GO composites are much lower than that of HMX/Viton. In addition, GO sheets exhibit a better desensitizing effect than G sheets. These combined properties suggest that nano-GO has good compatibility with explosives and can be utilized as a desensitizer in HMX particles.

  14. The thermal response of HMX-TATB charges

    Science.gov (United States)

    Drake, R. C.

    2017-01-01

    One approach to achieving charge safety and performance requirements is to prepare formulations containing two (or more) explosives. The intention of this approach is that by judicious choice of explosives and binder the formulation will have the desirable features of the constituent materials. HMX and TATB have very different properties. In an attempt to achieve a formulation which has the safety and performance characteristics of TATB and HMX, respectively, a range of formulations were prepared. The thermal response of the formulations were measured in the One-Dimensional Time To Explosion (ODTX) configuration and compared to those of formulations containing only HMX and TATB. The response of the mixed formulations was found to be largely determined by the HMX component with the binder making a small contribution. A formulation with a Kel-F 800 binder had a much higher critical temperature than would have been expected based on the critical temperatures of formulations with HTPB-IPDI as the binder.

  15. Synthesis, thermolysis, and sensitivities of HMX/NC energetic nanocomposites.

    Science.gov (United States)

    Wang, Yi; Song, Xiaolan; Song, Dan; Liang, Li; An, Chongwei; Wang, Jingyu

    2016-07-15

    1,3,5,7-Tetranittro-1,3,5,7-tetrazocane/nitrocellulose (HMX/NC) nanocomposites were successfully synthesized by an improved sol-gel-supercritical method. NC nanoparticles with a size of ∼30nm were cross-linked to form a network structure, and HMX nanoparticles were imbedded in the nano-NC matrix. The key factors, i.e., the selection of catalyst and solvent, were probed. No phase transformation of the HMX occurred before or after fabrication, and the molecular structures of the HMX and NC did not change. Thermal analyses were performed, and the kinetic and thermodynamic parameters, such as activation energy (EK), per-exponent factor (lnAK), rate constant (k), activation heat (ΔH(≠)), activation free energy (ΔG(≠)), activation entropy (ΔS(≠)), critical temperature of thermal explosion (Tb), and critical heating rate of thermal explosion (dT/dt)Tb, were calculated. The results indicate that HMX/NC presented a much lower activation energy (165.03kJ/mol) than raw HMX (282.5kJ/mol) or raw NC (175.51kJ/mol). The chemical potential (ΔG(≠)) for the thermal decomposition of HMX/NC has a positive value, which means that the activation of the molecules would not proceed spontaneously. The significantly lower ΔH(≠) value of HMX/NC, which represents the heat needed to be absorbed by an explosive molecule to change it from its initial state to an activated state, implies that the molecules of HMX/NC are much easier to be activated than those of raw HMX. Similarly, the HMX/NC presented a much lower Tb (168.2°C) than raw HMX (283.2°C). From the results of the sensitivity tests, the impact and friction sensitivities of HMX/NC were significantly decreased compared with those of raw HMX, but the thermal sensitivity was distinctly higher. The activation of the particles under external stimulation was simulated, and the mechanism was found to be crucial. Combining the thermodynamic parameters, the mechanism as determined from the results of the sensitivity tests was

  16. Study on the Thermal Conductivity of HMX Explosive: Method Development and Theoretical Calculation%高能HMX炸药热导率的研究:方法建立和理论计算

    Institute of Scientific and Technical Information of China (English)

    陈军; 龙瑶; 陈栋泉

    2013-01-01

    高能炸药热导率参数的计算是一个难点问题.介绍了我们发展的两种计算复杂结构炸药单晶热导率的方法:第一种方法基于运动方程,推导出了固体内较直观简洁的热流公式,可以研究不同方向HMX炸药的热导率;第二种方法基于声子-声子散射模型,结合德拜模型,计算高压下HMX炸药的热导率.两种方法各有其优缺点.利用这两种方法,计算了HMX炸药在高压下的热导率,并得到了高压下HMX热导率随压强的变化关系.%The theoretical calculation on thermal conductivity of explosive is still one problem.We presented our developed two calculation methods for thermal conductivity of explosive.The first one is based on atomic motion equation.We derived the formulations of thermal flux in system and thermal conductivity of system.It is suitable to calculate the thermal conductivity in different directions.The second one is based on the phonon-phonon dispersion model and Debye model.This method can effectively calculate the thermal conductivity under pressure.Using these two methods,we have calculated the thermal conductivity of HMX under pressure,and deeply analyzed the factors which affect the thermal conductivity of HMX.

  17. Synthesis, thermolysis, and sensitivities of HMX/NC energetic nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yi, E-mail: wangyi528528@aliyun.com [School of Materials Science and Engineering, North University of China, Taiyuan 030051 (China); Song, Xiaolan, E-mail: songxiaolan00@126.com [School of Chemical Engineering and Environment, North University of China, Taiyuan 030051 (China); Song, Dan [China Ordnance Institute of Science and Technology, Beijing 100089 (China); Liang, Li; An, Chongwei; Wang, Jingyu [School of Chemical Engineering and Environment, North University of China, Taiyuan 030051 (China)

    2016-07-15

    Highlights: • A novel energetic nanocomposite (i.e., HMX/NC nanocomposites) was fabricated in which nano-HMX imbedded in nano-NC matrix. • The usage of catalysts and solvent, which dominated the fabrication, was discussed. • Thermodynamic and kinetic parameters were calculated to probe the thermal decomposition of HMX/NC. • Decomposition products were detected by DSC-IR analysis. • Friction, impact, and thermal sensitivity tests were performed and the mechanism about the results was discussed. - Abstract: 1,3,5,7-Tetranittro-1,3,5,7-tetrazocane/nitrocellulose (HMX/NC) nanocomposites were successfully synthesized by an improved sol-gel-supercritical method. NC nanoparticles with a size of ∼30 nm were cross-linked to form a network structure, and HMX nanoparticles were imbedded in the nano-NC matrix. The key factors, i.e., the selection of catalyst and solvent, were probed. No phase transformation of the HMX occurred before or after fabrication, and the molecular structures of the HMX and NC did not change. Thermal analyses were performed, and the kinetic and thermodynamic parameters, such as activation energy (E{sub K}), per-exponent factor (lnA{sub K}), rate constant (k), activation heat (ΔH{sup ≠}), activation free energy (ΔG{sup ≠}), activation entropy (ΔS{sup ≠}), critical temperature of thermal explosion (T{sub b}), and critical heating rate of thermal explosion (dT/dt){sub Tb}, were calculated. The results indicate that HMX/NC presented a much lower activation energy (165.03 kJ/mol) than raw HMX (282.5 kJ/mol) or raw NC (175.51 kJ/mol). The chemical potential (ΔG{sup ≠}) for the thermal decomposition of HMX/NC has a positive value, which means that the activation of the molecules would not proceed spontaneously. The significantly lower ΔH{sup ≠} value of HMX/NC, which represents the heat needed to be absorbed by an explosive molecule to change it from its initial state to an activated state, implies that the molecules of HMX/NC are

  18. Biotransformation of RDX and HMX by Anaerobic Granular Sludge with Enriched Sulfate and Nitrate.

    Science.gov (United States)

    An, Chunjiang; Shi, Yarong; He, Yanling; Huang, Guohe; Liu, Yonghong; Yang, Shucheng

    2017-05-01

      RDX and HMX are widely used energetic materials and they are recognized as environmental contaminants at numerous locations. The present study investigated the biotransformation of RDX and HMX by anaerobic granular sludge under sulfate- and nitrate-enriched conditions. The results showed that RDX and HMX could be transformed by anaerobic granular sludge when nitrate was present. However, the biotransformation of RDX and HMX was negatively influenced, especially with high nitrate concentrations. Sulfate-enriched conditions were more favorable for the removal of ammunition compounds by anaerobic granular sludge than nitrate-enriched conditions. The removal of RDX and HMX under both nitrate- and sulfate-enriched conditions was facilitated by the use of glucose as additional substrate. This knowledge may help identify factors required for rapid removal of RDX and HMX in high-rate bioreactors. These results can also be applied to devise an appropriate and practical biological treatment strategy for explosive contaminated wastewater.

  19. HMX/TATB/binder development

    Energy Technology Data Exchange (ETDEWEB)

    Stallings, T.L.; Osborn, A.G.; Schaffer, C.L.; Crutchmer, J.A.

    1981-05-01

    The processing and sensitivity characteristics of three HMX/TATB/Binder formulations were investigated. Viton A, Kraton G 1650, and Estane 5702-F1 binders were studied. The thermal stabilities of these compositions are near those of HMX/binder formulations, whereas impact, skid and friction sensitivity levels are less than HMX compositions, but greater than those of TATB/binder systems.

  20. Influence of Temperature on Thermal Expansion Coefficient and Thermal Conductivity of HMX Based Polymer Bonded Explosive%温度对HMX基PBX炸药热膨胀系数和热导率的影响

    Institute of Scientific and Technical Information of China (English)

    韦兴文; 周筱雨; 王培; 涂小珍; 王翕

    2012-01-01

    The effect of temperature on thermal expansion and thermal conductivity of the HMX based polymer bonded explosive (PBX) were investigated by a thermal expansion analyzer and a flash thermal conductivity analyzer. The results show that coefficient of thermal expansion of HMX based PBX is about 5. 34 × 10-5 K-1 below 330K, which rapidly reachs to 13. 47 ×10-3 K-1 at temperature ranging from 330K to 350K, and decreases to 8. 04 × 10-5 K-1 above 350K. The specific heat capacity increases monotonically as temperature increasing, which ranging from 0. 978J · g-1 · K-1 to 1. 254J · g-1 · K-1 between 293K and 373K. But it is abnormal big at temperature about 343K as a result of the molten of the binder. The thermal diffusivity is 0. 256mm2 · s-1 at 293K and decreases to 0. 179mm2 · s-1 at 373K. The thermal conductivity is 0. 462W · m-1 · K-1 at 293K, decreasing to 0. 406W · m-1 · K-1 at 373K. The thermal conductivity and specific heat capacty variation with the temperature are established based on heat transfer theory of molecular crystal, and the thermal conductivities of HMX based PBX calculated from the two-phase vertical system model are in good agreement with the experiment%用热膨胀仪和闪光导热仪研究了温度对HMX基PBX的热膨胀系数和热导率的影响.结果表明,在低于330K时,HMX基PBX的线膨胀系数约为5.34×10-5 K-1;在330~350K,线膨胀系数迅速增大到13.47×10-5K-1,随着黏结剂软化,线膨胀系数随之减小到8.04×10-5K-1.在293~373K,HMX基PBX的比热容从0.978J·g-1·K-1线性增长到1.254J·g-1·K-1,但在343K附近黏结剂融化存在异常偏大值;HMX基PBX的热扩散率从0.256mm2·s-1下降至0.179mm2·s-1,通过比热和热扩散率实验数据计算获得的热导率从0.462W·m-1·K-1下降至0.406W·m-1·K-1.基于分子晶体传热理论模型建立了比热和导热系数的温度关系函数,HMX基PBX的导热机制符合两相串联模型.

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

    Science.gov (United States)

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

    2016-10-01

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

  2. Addition of RDX/HMX on the Ignition Behaviour of Boron-Potassium Nitrate Pyrotechnic Charge

    Directory of Open Access Journals (Sweden)

    K.R. Rani Krishnan

    2006-07-01

    Full Text Available Boron-potassium nitrate (B-KNO3 (25/75 is a well-known pyrotechnic composition whichfinds application as energy-release system for small-calibre rockets and pyrogen igniters forlarger motors. The decomposition of the oxidiser in this composition is endothermic which canbe activated by the addition of high explosives, which decompose exothermically. This paperdescribes the influence of two nitramine explosives, RDX and HMX, on the ignition characteristicsof B-KNO3 composition using thermogravimetry, differential scanning calorimetry, heat andpressure output measurements. Different compositions were prepared by varying the amount ofRDX/HMX from 10 per cent to 50 per cent. Thermal studies on the B-KNO3/high explosivemixtures reveal that these undergo two-stage decomposition. The first stage corresponds to thedecomposition of high explosive and the second stage corresponds to that of the reaction betweenB and KNO3. Kinetic parameters were calculated for both the stages of TG curves using Coats-Redfern and Mac Callum-Tanner methods. Ignition temperature of B-KNO3 decreases on theaddition of RDX/HMX while the onset of RDX or HMX decomposition is not significantly affectedby B-KNO3. The pressure output of B-KNO3 increases on adding RDX/HMX. The heat outputof B-KNO3 is not much affected by the addition of RDX or HMX, even though the heat ofexplosion of RDX and HMX are low. This is due to the reaction between the combustion productsof RDX/HMX and reaction products of B-KNO3 to form more exothermic products like B2O3,releasing extra heat. The flame temperature of the charge increases while the average molecularweight of the products of combustion decreases as the RDX/HMX content increases. Thus, thecharge, on addition of RDX or HMX, produces higher pressure output, maintaining the heatoutput at comparable levels.

  3. Electronic excitation energies in crystals of PETN, RDX and HMX

    Science.gov (United States)

    Mukhanov, A. E.

    2014-05-01

    The key role in the model of detonation based on metallization of an explosive plays a fundamental band gap of a molecular crystal. For determining it in a shocked crystal prerequisite calculation for perfect PETN, RDX, and HMX is performed at 0K. Densities of states for these explosives are obtained and fundamental gaps are determined. Calculations are done within the framework of the Density Functional Theory and its planewave and pseudopotential implementation in the ABINIT package.

  4. Damaging HMX/HTPB formulations: In-situ compression imaging using X-ray micro computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, Brian M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cordes, Nikolaus Lynn [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tappan, Bryce C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Thompson, Darla Graff [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Manner, Virginia Warren [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-04-17

    HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) is a powerful high explosive that is routinely used in formulations such as PBX 9501. Much remains to be learned about the performance and mechanical properties of HMX formulations such as these, particularly after dynamic damage has occurred. We have prepared formulations with HMX using hydroxyl terminated polybutadiene (HTPB) binder in order to form an explosive that is relatively insensitive to mild stimuli, analogous to PBXB-110 (different only is substitution of dioctyladipate (DO) for isodecyl pelargonate).

  5. A Molecular Dynamics simulation of Hugoniot curves of HMX using ReaxFF and its application in SPH modeling of macroscale terminal effects

    Science.gov (United States)

    Liu, Gui-Rong; Wang, Gangyu; Peng, Qing; de, Suvranu

    2015-06-01

    HMX is a widely used high explosive. Hugoniot curve is a valuable tool for analyzing the equations of state, and is of importance for all energetic materials including HMX. The Hugoniot curves serve as one of the key character in continuum modeling of high explosives. It can be obtained from experimental measurements, and recently also from computational studies. In this study, the Hugoniot curve of HMX is calculated using a multi-scale shock technique via Molecular Dynamics (MD) simulations, where the reactive force field ReaxFF is obtained from Quantum Mechanics calculations and tailored for HMX. It is found that our MD Hugoniot curve of HMX from the optimized ReaxFF potential agree well with experiments. The MD Hugoniot curve of HMX is also incorporated in our in-house Smoothed Particle Hydrodynamics (SPH) code for the modeling of the macro-scale explosive behaviors of HMX explosives and HMX cased in a 3D cylinder. The authors would like to acknowledge the generous financial support from the Defense Threat Reduction Agency (DTRA) Grant HDTRA1-13-1-0025.

  6. Melt Cast High Explosives

    Directory of Open Access Journals (Sweden)

    Stanisław Cudziło

    2014-12-01

    Full Text Available [b]Abstract[/b]. This paper reviews the current state and future developments of melt-cast high explosives. First the compositions, properties and methods of preparation of trinitrotoluene based (TNT conventional mixtures with aluminum, hexogen (RDX or octogen (HMX are described. In the newer, less sensitive explosive formulations, TNT is replaced with dinitroanisole (DNANDNANDNAN and nitrotriazolone (NTONTONTO, nitroguanidine (NG or ammonium perchlorate (AP are the replacement for RDRDX and HMX. Plasticized wax or polymer-based binder systems for melt castable explosives are also included. Hydroxyl terminated polybutadiene (HPTB is the binder of choice, but polyethylene glycol, and polycaprolactone with energetic plasticizers are also used. The most advanced melt-cast explosives are compositions containing energetic thermoplastic elastomers and novel highly energetic compounds (including nitrogen rich molecules in whose particles are nanosized and practically defect-less.[b]Keywords[/b]: melt-cast explosives, detonation parameters

  7. Method for synthesizing HMX

    Science.gov (United States)

    McGuire, Raymond R.; Coon, Clifford L.; Harrar, Jackson E.; Pearson, Richard K.

    1984-01-01

    A method and apparatus for electrochemically synthesizing N.sub.2 O.sub.5 cludes oxidizing a solution of N.sub.2 O.sub.4 /HNO.sub.3 at an anode, while maintaining a controlled potential between the N.sub.2 O.sub.4 /HNO.sub.3 solution and the anode. A potential of about 1.35 to 2.0 V vs. SCE is preferred, while a potential of about 1.80 V vs. SCE is most preferred. Thereafter, the N.sub.2 O.sub.5 is reacted with either 1.5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane (DADN) or 1,3,5,7-tetraacetyl-1,3,5,7-tetraazacyclooctane (TAT) to form cyclotetramethylenetetraamine (HMX).

  8. Introduction to High Explosives Science

    Energy Technology Data Exchange (ETDEWEB)

    Skidmore, Cary Bradford [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    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.

  9. Theoretical insights into the stabilities, detonation performance, and electrostatic potentials of cocrystals containing α- or β-HMX and TATB, FOX-7, NTO, or DMF in various molar ratios.

    Science.gov (United States)

    Song, Ken-Peng; Ren, Fu-de; Zhang, Shu-Hai; Shi, Wen-Jing

    2016-10-01

    A molecular dynamics method was employed to study the binding energies associated with the cocrystallization (at selected crystal planes) of either 1,3,5-triamino-2,4,6-trinitro-benzene (TATB), 1,1-diamino-2,2-dinitroethylene, 3-nitro-1,2,4-triazol-5-one (TATB, FOX-7, and NTO, respectively, all of which are explosives), or N,N-dimethylformamide (DMF, a nonenergetic solvent) in various molar ratios with 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane in its α and β conformations (α-HMX and β-HMX, respectively). The results showed that the cocrystals with low molar ratios (2:1, 1:1, 1:2, and 1:3) were the most stable. The binding energies of HMX/NTO and HMX/DMF were larger than those of HMX/TATB and HMX/FOX-7. According to the calculated stabilities, HMX prefers to adopt its α form in HMX/TATB and its β form in HMX/NTO, whereas the two forms coexist in HMX/FOX-7. For HMX/TATB, HMX/NTO, and α-HMX/FOX-7, increasing the proportion of the cocrystal component with the highest detonation heat (HMX in the first two cases, FOX-7 in the latter) increases the detonation heat, velocity, and pressure of the cocrystal. However, increasing the proportion of the component with the highest detonation heat in β-HMX/FOX-7 and γ-CL-20/FOX-7 increases the detonation heat of the cocrystal but decreases its detonation velocity. An investigation of the surface electrostatic potential revealed how the sensitivity changes upon cocrystal formation. Graphical Abstract Surface electrostatic potential of HMX/TATB.

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

    Science.gov (United States)

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

    2010-04-01

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

  11. Photocatalysis for the destruction of aqueous TNT, RDX, and HMX

    Energy Technology Data Exchange (ETDEWEB)

    Showalter, S.K.; Prairie, M.R.; Stange, B.M.; Rodacy, P.J.; Leslie, P.K.

    1994-12-31

    The photo-destruction of the high explosives HMX, RDX and TNT was investigated using two systems (ozone versus titanium dioxide), two reactors (pot vs annular reactor), and two types of lamps (1000 Watt Hg-Xe vs 25 Watt LP Hg). A mass balance was performed on reactions executed under pseudo-solar conditions, and relative reaction rates and products were compared for ozone and titanium dioxide based processes. The ratios of relative product formation is also discussed. Results show that there was little difference in the reactions performed in the annular reactor when either ozone or titanium oxide were used. The chemistry of RDX and HMX are very similar, as expected. Future work involving the mechanism is also discussed.

  12. Characterization of hypervelocity metal fragments for explosive initiation

    Science.gov (United States)

    Yeager, John D.; Bowden, Patrick R.; Guildenbecher, Daniel R.; Olles, Joseph D.

    2017-07-01

    The fragment impact response of two plastic-bonded explosive (PBX) formulations was studied using explosively driven aluminum fragments. A generic aluminum-capped detonator generated sub-mm aluminum particles moving at hypersonic velocities. The ability of these fragments to initiate reaction or otherwise damage two PBX materials was assessed using go/no-go experiments at standoff distances of up to 160 mm. Lower density PBX 9407 (RDX-based) was initiable at up to 115 mm, while higher density PBX 9501 (HMX-based) was only initiable at up to 6 mm. Several techniques were used to characterize the size, distribution, and velocity of the particles. Witness plate materials, including copper and polycarbonate, and backlit high speed video were used to characterize the distribution of particles, finding that the aluminum cap did not fragment homogeneously but rather with larger particles in a ring surrounding finer particles. Finally, precise digital holography experiments were conducted to measure the three-dimensional shape and size of the fastest-moving fragments, which ranged between 100 and 700 μm and traveled between 2.2 and 3.2 km/s. Crucially, these experiments showed variability in the fragmentation in terms of the number of fragments at the leading edge of the fragment field, indicating that both single and multiple shock impacts could be imparted to the target material. These types of data are critical for safety experiments and hydrocode simulations to quantify shock-to-detonation transition mechanisms and the associated risk-margins for these materials.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-08-01

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

  14. Investigation of hazards associated with plastic bonded starter mix manufacturing processes

    Science.gov (United States)

    1971-01-01

    An investigation to determine the hazards potential evaluation of plastic bonded starter mix (PBSM) production processes and the application to the M18 and M7A3 grenades is reported. The investigation indicated: (1) the materials with the greatest hazards characteristics, (2) process operating stations most likely to initiate hazardous conditions, (3) the test program required to examine ignition characteristics and process hazards, and (4) the method of handling the accumulated information from testing and safety analyses.

  15. Surface properties of HMX crystal

    Science.gov (United States)

    Yee, R. Y.; Adicoff, A.; Dibble, E. J.

    1980-01-01

    The surface properties of Beta-HMX crystals were studied. The surface energies of three principal crystal faces were obtained by measuring contact angles with several reference liquids. The surface energies and polarity of the three crystal faces are found to be different.

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

    Institute of Scientific and Technical Information of China (English)

    LIAN Dan; LU Lai-Yu; WEI Dong-Qing; ZHANG Qing-Ming; GONG Zi-Zheng; GUO Yong-Xin

    2008-01-01

    @@ Density functional theory (DFT) with local density approximation (LDA) is employed to study the structural and electronic properties of the high explosive octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) under high pressure compression up to 40 GPa.Pressure dependences of the cell volume,lattice constants,and molecular geometry of solid β-HMX are presented and discussed.It is found that N-N and N-C bonds are subject to significant change.

  17. Finite element code development for modeling detonation of HMX composites

    Science.gov (United States)

    Duran, Adam V.; Sundararaghavan, Veera

    2017-01-01

    In this work, we present a hydrodynamics code for modeling shock and detonation waves in HMX. A stable efficient solution strategy based on a Taylor-Galerkin finite element (FE) discretization was developed to solve the reactive Euler equations. In our code, well calibrated equations of state for the solid unreacted material and gaseous reaction products have been implemented, along with a chemical reaction scheme and a mixing rule to define the properties of partially reacted states. A linear Gruneisen equation of state was employed for the unreacted HMX calibrated from experiments. The JWL form was used to model the EOS of gaseous reaction products. It is assumed that the unreacted explosive and reaction products are in both pressure and temperature equilibrium. The overall specific volume and internal energy was computed using the rule of mixtures. Arrhenius kinetics scheme was integrated to model the chemical reactions. A locally controlled dissipation was introduced that induces a non-oscillatory stabilized scheme for the shock front. The FE model was validated using analytical solutions for SOD shock and ZND strong detonation models. Benchmark problems are presented for geometries in which a single HMX crystal is subjected to a shock condition.

  18. Deflagration-to-detonation transition in granular HMX

    Science.gov (United States)

    Campbell, A. W.

    1980-01-01

    Granular HMX of three degrees of fineness was packed into heavy-walled steel tubes closed at both ends. Ignition was obtained at one end using an intimate mixture of finely divided titanium and boron as an igniter that produced heat with little gas. The distance to detonation was determined by examination of the resulting tube fragments. By inserting tightly-fitted neoprene diaphragms periodically into the HMX column, it was shown that the role of convective combustion was limited to the initial stage of the deflagration to detonation (DDT) process. Experiments in which various combinations of two of the three types of HMX were loaded into the same tube showed that heating by adiabatic shear of explosive grains was an essential factor in the final buildup to detonation. A description of the DDT process is developed in which conductive burning is followed in turn by convective burning, bed collapse with plug formation, onset of accelerated burning at the front of the plug through heating by intercrystalline friction and adiabatic shear, and intense shock formation resulting in high-order detonation.

  19. DDT Behavior of Waxed Mixtures of RDX, HMX, and Tetryl

    Science.gov (United States)

    1977-10-18

    NSWC/WOL TR 77-96 O DDT BEHAVIOR OF WAXED MIXTURES OF " RDX, HMX, AND TETRYL BY DONNA PRICE and RICHARD R. BERNECKER RESEARCH AND TECHNOLOGY...50.95 mm OD) with heavy end closures was used. A B/ KNO3 ignitor (1) was used to ignite one end of the 295.4 mm explosive column. Charge loading, tube...data reduction are also as in reference 1 with the modification for strain gages given in reference 2. I. R. R. Bernecker and D. Price , "Transition

  20. Deflagration to Detonation Transition Behavior of Aluminized HMX

    Science.gov (United States)

    1979-06-04

    NSWC TR 79-119 tLN DEFLAG RATION TO DETONATION TRANSITION BEHAVIOR OF ALUMINIZED HMX BY DONNA PRICE A. R. CLAIRMONT, JR 0 RESEARCH AND TECHNOLOGY...Detonation of Solid Explosives," J. Chem. Soc., 4154, 1960. 3Bernecker, R. R. and Price , D., "Studies in the Transition from Deflagration to Detonation in...Laboratory TR 74-186. 4 NSWC TR 79-119 tube with heavy end closures. The column length of the 0.35 g of 25/75 B/ KNO3 ignitor is 6.3 mm; the length of

  1. Determination of the HMX and RDX content in synthesized energetic material by HPLC, FT-MIR, and FT-NIR spectroscopies

    Directory of Open Access Journals (Sweden)

    Mattos Elizabeth C.

    2004-01-01

    Full Text Available A new method has been developed for determining the content of mixtures of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX, the HMX/RDX ratio, in explosive compositions by Fourier transform infrared spectroscopy (FT-IR, in the regions MIR (mid infrared and NIR (near infrared with reference values obtained by chromatographic analysis (HPLC. Plots of relative MIR (A917 / A783 or NIR absorbance values (A4412 / A4317 versus HMX/RDX ratio determined by HPLC analysis revealed good linear relationships.

  2. Lidar Detection of Explosives Traces

    Directory of Open Access Journals (Sweden)

    Bobrovnikov Sergei M.

    2016-01-01

    Full Text Available The possibility of remote detection of traces of explosives using laser fragmentation/laser-induced fluorescence (LF/LIF is studied. Experimental data on the remote visualization of traces of trinitrotoluene (TNT, hexogen (RDX, trotyl-hexogen (Comp B, octogen (HMX, and tetryl with a scanning lidar detector of traces of nitrogen-containing explosives at a distance of 5 m are presented.

  3. Explosive Residue Detection by Laser Surface Photo-Fragmentation-Fragment Detection Spectroscopy. 2. In Situ and Real-Time Monitoring of RDX. HMX, CL20, and TNT, by an Improved Ion Probe

    Science.gov (United States)

    2005-04-01

    or resonance-enhanced multiphoton ionization (REMPI) (7). The NO fragment is characteristic of the nitrogen dioxide (NO2) functional group that is...highest bond dissociation energy for R–NO2 scission by at least 20 kcal/mol. In part, this is because the NO2 group in TNT is bonded to a carbon ...explosives, Optics Communications 2002, 204 (1-6), 327–331. 5. Arusi-Parpar, T.; Heflinger, D.; Lavi, R. Photodissociation followed by laser-induced

  4. Unreacted Equations of State of Shocked Single Crystal PETN and Beta-HMX

    Science.gov (United States)

    Zaug, Joseph; Armstrong, Michael; Crowhurst, Jonathan; Ferranti, Louis; Bastea, Sorin; Fried, Lawrence

    2014-03-01

    We report results from ultrafast shockwave experiments conducted on single crystal high explosives. Ultrafast shock studies can enable high throughput characterizations of unreacted equations of state to higher pressures than previously reported and also quantify the magnitude of anisotropic mechanical response to shock waves. Our ultrafast results yield -as of this writing- [110] PETN data up to a pressure of 26 GPa, which is 1.6x higher than published mid-scale gun results. Published HMX shock data are strikingly sparse; seven points up to approximately 10 GPa are reported from shocked solvent-pressed beta-HMX and Robert Craig reported three single crystal points (undisclosed crystal orientation) between 34 and 42 GPa. Two nonhydrostatic cold-compression diamond-anvil cell studies, u-Raman + u-XRD, and u-Raman + deflagration rates, report a transition in HMX, possibly shear induced, beginning at 26-27 GPa. A previously posed question is whether Craig's data are affected by this transition. ∖pard An analysis of our results for [010] beta-HMX indicate it is less compressible than portrayed by the commonly accepted Hugoniot, which is based on a parameterized third-order Birch-Murnaghan model EoS using the ten before mentioned shock wave measurements and the more recent cold-compression u-XRD study by Yoo et al. Work performed by the U.S. Department of Energy jointly by Lawrence Livermore National Laboratory; Contract DE-AC52-07NA27344.

  5. Carbon and nitrogen isotope ratios of factory-produced RDX and HMX.

    Science.gov (United States)

    Howa, John D; Lott, Michael J; Chesson, Lesley A; Ehleringer, James R

    2014-07-01

    RDX and HMX are explosive compounds commonly used by the military and also occasionally associated with acts of terrorism. The isotopic characterization of an explosive can be a powerful approach to link evidence to an event or an explosives cache. We sampled explosive products and their reactants from commercial RDX manufacturers that used the direct nitration and/or the Bachmann synthesis process, and then analyzed these materials for carbon and nitrogen isotope ratios. For manufacturers using the Bachmann process, RDX (13)C enrichment relative to the hexamine substrate was small (+0.9‰) compared to RDX produced using the direct nitration process (+8.2‰ to +12.0‰). RDX (15)N depletion relative to the nitrogen-containing substrates (-3.6‰) was smaller in the Bachmann process than in the direct nitration process (-12.6‰ to -10.6‰). The sign and scale of these differences agree with theorized mechanisms of mass-dependent fractionation. We also examined the isotopic relationship between RDX and HMX isolated from explosive samples. The δ(13)C and δ(15)N values of RDX generally matched those of the HMX with few exceptions, most notably from a manufacturer known to make RDX using two different synthesis processes. The range in δ(13)C values of RDX in a survey of 100 samples from 12 manufacturers spanned 33‰ while the range spanned by δ(15)N values was 26‰; these ranges were much greater than any previously published observations. Understanding the relationship between products and reactants further explains the observed variation in industrially manufactured RDX and can be used as a diagnostic tool to analyze explosives found at a crime scene. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. The response of the HMX-based material PBXN-9 to thermal insults: thermal decomposition kinetics and morphological changes

    Energy Technology Data Exchange (ETDEWEB)

    Glascoe, E A; Hsu, P C; Springer, H K; DeHaven, M R; Tan, N; Turner, H C

    2010-12-10

    PBXN-9, an HMX-formulation, is thermally damaged and thermally decomposed in order to determine the morphological changes and decomposition kinetics that occur in the material after mild to moderate heating. The material and its constituents were decomposed using standard thermal analysis techniques (DSC and TGA) and the decomposition kinetics are reported using different kinetic models. Pressed parts and prill were thermally damaged, i.e. heated to temperatures that resulted in material changes but did not result in significant decomposition or explosion, and analyzed. In general, the thermally damaged samples showed a significant increase in porosity and decrease in density and a small amount of weight loss. These PBXN-9 samples appear to sustain more thermal damage than similar HMX-Viton A formulations and the most likely reasons are the decomposition/evaporation of a volatile plasticizer and a polymorphic transition of the HMX from {beta} to {delta} phase.

  7. Modeling initiation trains based on HMX and TATB

    Science.gov (United States)

    Drake, R. C.; Maisey, M.

    2017-01-01

    There will always be a requirement to reduce the size of initiation trains. However, as the size is reduced the performance characteristics can be compromised. A detailed science-based understanding of the processes (ignition and growth to detonation) which determine the performance characteristics is required to enable compact and robust initiation trains to be designed. To assess the use of numerical models in the design of initiation trains a modeling study has been undertaken, with the aim of understanding the initiation of TATB and HMX charges by a confined, surface mounted detonator. The effect of detonator diameter and detonator confinement on the formation of dead zones in the acceptor explosives has been studied. The size of dead zones can be reduced by increasing the diameter of the detonator and by increasing the impedance of the confinement. The implications for the design of initiation trains are discussed.

  8. The Combustion of HMX. [burning rate at high pressures

    Science.gov (United States)

    Boggs, T. L.; Price, C. F.; Atwood, A. I.; Zurn, D. E.; Eisel, J. L.

    1980-01-01

    The burn rate of HMX was measured at high pressures (p more than 1000 psi). The self deflagration rate of HMX was determined from 1 atmosphere to 50,000 psi. The burning rate shows no significant slope breaks.

  9. Ignition and growth reactive flow modeling of recent HMX/TATB detonation experiments

    Science.gov (United States)

    Tarver, Craig M.

    2017-01-01

    Two experimental studies in which faster HMX detonation waves produced oblique detonation waves in adjoining slower detonating TATB charges were modeled using the Ignition and Growth (I&G) reactive flow detonation model parameters for PBX 9501 (95% HMX / 2.5% Estane / 2.5% BDNPA/F) and PBX 9502 (95% TATB / 5% Kel-F binder). Matignon et al. used X1 explosive (96% HMX / 4% binder) to drive an oblique detonation wave into an attached charge of T2 explosive (97% TATB / 3% binder). The flow angles were measured in the T2 shock initiation region and in steady T2 detonation. Anderson et al. used detonating PBX 9501 slabs of various thicknesses ranging from 0.56 mm to 2.5 mm to create oblique detonation waves in 8 mm thick slabs of PBX 9502. Several diagnostics were employed to: photograph the waves; measure detonation velocities and flow angles; and determine the output of the PBX 9501 slabs, the PBX 9502 slabs, and the "initiation regions" using LiF windows and PDV probes.

  10. Toward Improved Fidelity of Thermal Explosion Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, A L; Becker, R; Howard, W M; Wemhoff, A

    2009-07-17

    We will present results of an effort to improve the thermal/chemical/mechanical modeling of HMX based explosive like LX04 and LX10 for thermal cook-off. The original HMX model and analysis scheme were developed by Yoh et.al. for use in the ALE3D modeling framework. The current results were built to remedy the deficiencies of that original model. We concentrated our efforts in four areas. The first area was addition of porosity to the chemical material model framework in ALE3D that is used to model the HMX explosive formulation. This is needed to handle the roughly 2% porosity in solid explosives. The second area was the improvement of the HMX reaction network, which included the inclusion of a reactive phase change model base on work by Henson et.al. The third area required adding early decomposition gas species to the CHEETAH material database to develop more accurate equations of state for gaseous intermediates and products. Finally, it was necessary to improve the implicit mechanics module in ALE3D to more naturally handle the long time scales associated with thermal cook-off. The application of the resulting framework to the analysis of the Scaled Thermal Explosion (STEX) experiments will be discussed.

  11. Thermal Decomposition Kinetics of HMX

    Energy Technology Data Exchange (ETDEWEB)

    Burnham, A K; Weese, R K

    2004-11-18

    Nucleation-growth kinetic expressions are derived for thermal decomposition of HMX from a variety of thermal analysis data types, including mass loss for isothermal and constant rate heating in an open pan and heat flow for isothermal and constant rate heating in open and closed pans. Conditions are identified in which thermal runaway is small to nonexistent, which typically means temperatures less than 255 C and heating rates less than 1 C/min. Activation energies are typically in the 140 to 165 kJ/mol range for open pan experiments and about 150 to 165 kJ/mol for sealed pan experiments. Our activation energies tend to be slightly lower than those derived from data supplied by the University of Utah, which we consider the best previous thermal analysis work. The reaction clearly displays more than one process, and most likely three processes, which are most clearly evident in open pan experiments. The reaction is accelerated in closed pan experiments, and one global reaction appears to fit the data well. Comparison of our rate measurements with additional literature sources for open and closed low temperature pyrolysis from Sandia gives a likely activation energy of 165 kJ/mol at 10% conversion.

  12. Thermal Decomposition Kinetics of HMX

    Energy Technology Data Exchange (ETDEWEB)

    Burnham, A K; Weese, R K

    2004-05-05

    Nucleation-growth kinetic expressions are derived for thermal decomposition of HMX from a variety of types of data, including mass loss for isothermal and constant rate heating in an open pan, and heat flow for isothermal and constant rate heating in open and closed pans. Conditions are identified in which thermal runaway is small to nonexistent, which typically means temperatures less than 255 C and heating rates less than 1 C/min. Activation energies are typically in the 140 to 150 kJ/mol regime for open pan experiments and about 160 kJ/mol for sealed pan experiments. Our activation energies are about 10% lower than those derived from data supplied by the University of Utah, which we consider the best previous work. The reaction clearly displays more than one process, and most likely three processes, which are most clearly evident in open pan experiments. The reaction is accelerated for closed pan experiments, and one global reaction appears to fit the data well.

  13. Thermal Decomposition Kinetics of HMX

    Energy Technology Data Exchange (ETDEWEB)

    Burnham, A K; Weese, R K

    2005-03-17

    Nucleation-growth kinetic expressions are derived for thermal decomposition of HMX from a variety of types of data, including mass loss for isothermal and constant rate heating in an open pan, and heat flow for isothermal and constant rate heating in open and closed pans. Conditions are identified in which thermal runaway is small to nonexistent, which typically means temperatures less than 255 C and heating rates less than 1 C/min. Activation energies are typically in the 140 to 165 kJ/mol regime for open pan experiments and about 150-165 kJ/mol for sealed-pan experiments. The reaction clearly displays more than one process, and most likely three processes, which are most clearly evident in open pan experiments. The reaction is accelerated for closed pan experiments, and one global reaction fits the data fairly well. Our A-E values lie in the middle of the values given in a compensation-law plot by Brill et al. (1994). Comparison with additional open and closed low temperature pyrolysis experiments support an activation energy of 165 kJ/mol at 10% conversion.

  14. Observation and modeling of deflagration-to-detonation transition (DDT) in low-density HMX

    Science.gov (United States)

    Tringe, Joseph W.; Vandersall, Kevin S.; Reaugh, John E.; Levie, Harold W.; Henson, Bryan F.; Smilowitz, Laura B.; Parker, Gary R.

    2017-01-01

    We employ simultaneous flash x-ray radiography and streak imaging, together with a multi-phase finite element model, to understand deflagration-to-detonation transition (DDT) phenomena in low-density (˜1.2 gm/cm3) powder of the explosive cyclotetramethylene-tetranitramine (HMX). HMX powder was lightly hand-tamped in a 12.7 mm diameter column, relatively lightly-confined in an optically-transparent polycarbonate cylinder with wall thickness 25.4 mm. We observe apparent compaction of the powder in advance of the detonation transition by the motion of small steel spheres pre-emplaced throughout the length of explosive. High-speed imaging along the explosive cylinder length provides a more temporally continuous record of the transition that is correlated with the high-resolution x-ray image record. Preliminary simulation of these experiments with the HERMES model implemented in the ALE3D code enables improved understanding of the explosive particle burning, compaction and detonation phenomena which are implied by the observed reaction rate and transition location within the cylinder.

  15. Observation and modeling of deflagration-to-detonation (DDT) transition in low-density HMX

    Science.gov (United States)

    Tringe, Joseph; Vandersall, Kevin; Reaugh, Jack; Levie, Harold; Henson, Bryan; Smilowitz, Laura; Parker, Gary

    2015-06-01

    We employ simultaneous flash x-ray radiography and streak imaging, together with a multi-phase finite element model, to understand deflagration-to-detonation transition (DDT) phenomena in low-density (~ 1.2 gm/cm3) powder of the explosive cyclotetramethylene-tetranitramine (HMX). HMX powder was lightly hand-tamped in a 12.7 mm diameter column, relatively lightly-confined in an optically-transparent polycarbonate cylinder with wall thickness 25.4 mm. We observe apparent compaction of the powder in advance of the detonation transition, both by x-ray contrast and by the motion of small steel spheres pre-emplaced throughout the length of explosive. High-speed imaging along the explosive cylinder length provides a temporally continuous record of the transition that is correlated with the high-resolution x-ray image record. Preliminary simulation of these experiments with the HERMES model implemented in the ALE3D code enables improved understanding of the explosive particle burning, compaction and detonation phenomena which are implied by the observed reaction rate and transition location within the cylinder. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

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

    Energy Technology Data Exchange (ETDEWEB)

    Harrier, Danielle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    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.

  17. The Scaled Thermal Explosion Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Wardell, J F; Maienschein, J L

    2002-07-05

    We have developed the Scaled Thermal Explosion Experiment (STEX) to provide a database of reaction violence from thermal explosion for explosives of interest. Such data are needed to develop, calibrate, and validate predictive capability for thermal explosions using simulation computer codes. A cylinder of explosive 25, 50 or 100 mm in diameter, is confined in a steel cylinder with heavy end caps, and heated under controlled conditions until reaction. Reaction violence is quantified through non-contact micropower impulse radar measurements of the cylinder wall velocity and by strain gauge data at reaction onset. Here we describe the test concept, design and diagnostic recording, and report results with HMX- and RDX-based energetic materials.

  18. Analysis of thermally-degrading, confined HMX

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, M.L.; Schmitt, R.G.; Renlund, A.M.

    1996-12-01

    The response of a thermally-degrading, confined HMX pellet is analyzed using a Reactive Elastic-Plastic (REP) constitutive model which is founded on the collapse and growth of internal inclusions resulting from physical and chemical processes such as forced displacement, thermal expansion, and/or decomposition. Axial stress predictions compare adequately to data. Deficiencies in the model and future directions are discussed.

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

    Science.gov (United States)

    2014-04-01

    Plant HMTD Hexamethylene triperoxide HMX Cyclotrimethylene tetranitrate IED Improvised explosive device IR Infrared IRE Internal reflection... chromatography MIR Mid-infrared n Real refractive index PBA Poly(1,4-butylene adipate) PETN Pentaerythritol tetranitrate PIB Poly(isobutylene) PMMA...was removed from the holder, the anti-reflection coated surfaces were gently cleaned with lens paper and solvent to remove any traces of contamination

  20. The Anisotropic Dynamic Response of Ultrafast Shocked Single Crystal PETN and Beta-HMX

    Science.gov (United States)

    Zaug, Joseph; Armstrong, Michael; Crowhurst, Jonathan; Austin, Ryan; Ferranti, Louis; Fried, Laurence; Bastea, Sorin

    2015-06-01

    We report results from ultrafast shockwave experiments conducted on single crystal high explosives. Experimental results consist of 12 picosecond time-resolved dynamic response wave profile data, (ultrafast time-domain interferometry-TDI), which are used to validate calculations of anisotropic stress-strain behavior of shocked loaded energetic materials. In addition, here we present unreacted equations of state data from PETN and beta-HMX up to higher pressures than previously reported, which are used to extend the predictive confidence of hydrodynamic simulations. Our previous results derived from a 360 ps drive duration yielded anisotropic elastic wave response in single crystal beta-HMX ((110) and (010) impact planes). Here we provide results using a 3x longer drive duration to probe the plastic response regime of these materials. We compare our ultrafast time domain interferometry (TDI) results with previous gun platform results. Ultrafast time scale resolution TDI measurements further guide the development of continuum models aimed to study pore collapse and energy localization in shock-compressed crystals of beta-HMX. This work was performed under the auspices of the U.S. Department of Energy jointly by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

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

    Science.gov (United States)

    Mahon, K. S.; Lee, T.-W.

    2015-12-01

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

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

    Directory of Open Access Journals (Sweden)

    K. S. Mahon

    2015-12-01

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

  3. Toxicity and bioconcentration evaluation of RDX and HMX using sheepshead minnows in water exposures.

    Science.gov (United States)

    Lotufo, Guilherme R; Gibson, Alfreda B; Yoo, J Leslie

    2010-10-01

    Lethal effects of the explosives RDX and HMX were assessed using ten-day water exposures to juvenile sheepshead minnows (Cyprinodon variegatus). For RDX, maximum mortality occurred during the first two days of exposure with a 10-d median lethal concentration (LC50) of 9.9 mg L(-1). The RDX 10-d median lethal residue (LR50) was 9.6 mg kg(-1) (34.9 μmol kg(-1)) wet weight (ww), the first RDX critical body residue reported for fish. Previous investigations reported that RDX body residues in marine amphipods up to 96 μmol kg(-1) ww and in marine mussels up to 86 μmol kg(-1) ww failed to result in significant mortality. The highest HMX concentration tested, corresponding to its apparent solubility limit in seawater (2.0 mg L(-1)), and the associated mean body residue (3 mg kg(-1) or 14 μmol kg(-1) ww) resulted in no significant mortality for exposed minnows. The mean 10-d bioconcentration factors for RDX (0.6-0.9 L kg(-1)) and HMX (0.3-1.6 L kg(-1)) were typically lower than 1, reflecting the low bioaccumulative potential for these compounds. Published by Elsevier Inc.

  4. Synthesis and Characterization of High Energy Sheet Materials Based on HMX / RDX and Hydroxyl Terminated Polybutadiene

    Science.gov (United States)

    Elsharkawy, Karim; Guo, Lin; Taha, Elhussein; Fouda, Hany

    2017-07-01

    In this paper three types of thin sheets of highly energetic materials were prepared and characterized. The first based on 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX). The second type based on 1,3,5-trinitro-1,3,5-triazinane (RDX). Both types contain polyurethane (PU), formulated by hydroxyl terminated polybutadiene (HTPB) and Isophorondiisocyanate (IPDI). The third type based on (RDX) and polyisoprene (PI) as high elastomeric material. The first and second types of thin sheets were prepared by applying the casting technique while the third type was prepared by slurry technique then followed by rolling of the prepared beads of the RDX coated by PI. These high energy sheet materials were cured in oven at 60°C. The measured explosive properties of the prepared sheets were discussed and showed that the sensitivity to impact and friction of the prepared sheets explosives materials were markedly decreased when compared to pure HMX or pure RDX, but the sensitivity to heat was close to that of pure RDX. In spite of the markedly decrease in the sensitivity of these sheets, the explosive characteristics were nearly not affected the sheets have very good stress-strain values.

  5. Combustion of HMX-CMDB propellants. Pt. 1

    Energy Technology Data Exchange (ETDEWEB)

    Yano, Y.; Kubota, N.

    1985-12-01

    The combustion wave structure of HMX-CMDB (composite modified double-base) propellants was studied in order to elucidate the gas phase reaction mechanism and to understand the burning rate characteristics. Experiments were conducted to determine the thickness of the reaction zone, gaseous products in the dark zone, and the temperature profile in the combustion waves. The reaction rate in the dark zone is increased by the addition of HMX. This is caused by the equivalence ratio of the oxidizer/fuel in the dark zone shifting towards a stoichiometric ratio when HMX is added. However, the reaction rate in the fizz zone and the heat feedback from the gas phase to the burning surface is decreased by the addition of HMX. Thus, the burning rate of HMX-CMDB propellants decreases when HMX is mixed within double-base propellants.

  6. Mesoscale thermal-mechanical analysis of shocked induced granular explosives and polymer-bonded explosives

    Science.gov (United States)

    Wang, Xinjie; Wu, Yanqing; Huang, Fenglei

    2015-06-01

    The thermal-mechanical response of HMX-based granular explosives (GXs) and polymer-bonded explosives (PBXs) with variable number of crystals from 10 to 100 under impact loading is investigated with finite element software ABAQUS. A series of three dimensional mesoscale calculations are carried out with the crystal plasticity constitutive model for HMX crystals that accounts for nonlinear elasticity and crystalline plasticity and the viscoelastic model for the polymer binder. To make the analysis comparable, the morphology and the size of HMX crystals are kept the same for both GXs and PBXs. In order to quantify the effect of polymer binder under different strain rate, the calculation models are impacted with initial boundary velocities from 10 to 100 m/s. The results shows that the average pressure of PBXs is approximately 50% higher than GXs and that the localized stress and temperature is highly increased with the polymer binder, which indicates the crystal anisotropy as well as the polymer binder plays an important role in influencing the stress and thermal response of HMX crystals. The thermal-mechanical response analyzed here is essential to predict the formation of hot spot and the ignition of explosives.

  7. Preparation of ultrafine HMX and inhibition of reunion%超细奥克托今的制备及防团聚研究

    Institute of Scientific and Technical Information of China (English)

    王瑞浩; 邓延平; 王金英; 张景林

    2015-01-01

    Ultrafine HMX was prepared by the atomizing kinetic crystal method. Aiming at the prominant problems that HMX crystals would grow and reunite during the post-treatment process, different drying conditions were formulated, analyzed and stud-ied. In the experiment, it is found that freeze drying and adding surfactant PVP could effectively inhibit crystal growth and reunion. At last, the expanding process was carried out and 0.4~1.6 μm particles of ultrafine explosive HMX were prepared by optimizing drying conditions and adjusting the addition amount of PVP, and the efficiency could be the highest when 300 g of HMX was dried each time.%采用微团化动态结晶技术对原料HMX进行超细化,针对后处理过程HMX晶体长大和团聚的突出问题,制定不同干燥条件进行分析研究。实验得到冷冻干燥和加入表面活性剂PVP可有效地抑制晶体长大和团聚。最后进行放大实验,优化干燥条件和调节PVP的加入量,制得了0.4~1.6μm的HMX超细炸药,每次处理300 g HMX,效率最高。

  8. Aplicação da calorimetria exploratória diferencial no estudo da cinética de transição alfa -> delta HMX Application of differential scanning calorimetry in the study of the kinetics of the alpha -> delta transition in HMX

    Directory of Open Access Journals (Sweden)

    Gilson da Silva

    2004-12-01

    Full Text Available Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX or octogen is a white crystalline substance which occurs in four polymorphous forms. It is used in a wide variety of military and industrial formulations owing to its suitable properties. Researchers have demonstrated the usefulness of this energetic material in explosive components. In the present work we apply differential scanning calorimetry (DSC to measure the a ® d solid-solid phase transition energy of HMX. The results obtained by Kissinger's and Ozawa's methods were 487 and 495 kJ/mol, respectively.

  9. Microstructural characterization of pressed HMX material sets at differing densities

    Science.gov (United States)

    Molek, C. D.; Welle, E. J.; Wixom, R. R.; Ritchey, M. B.; Samuels, P.; Horie, Y.

    2017-01-01

    The detonation physics community has embraced the idea that initiation of high explosives (HE) proceeds from an ignition event through subsequent growth to steady detonation. A weakness of all the commonly used ignition and growth models is the microstructural characteristics of the HE are not explicitly incorporated in their ignition and growth terms. This is the case in spite of a demonstrated, but not well-understood, empirical link between particle morphology and initiation of HE. Morphological effects have been parametrically studied in many ways, the majority of efforts focus on establishing a tie between bulk powder metrics and initiation of the pressed beds. More recently, there has been a shift toward characterizing the microstructure of pressed beds in order to understand the underlying mechanisms governing initiation behavior. In this work, we have characterized the microstructures of two HMX classes pressed at three densities using ion bombardment techniques. We find more significant compaction associated with the larger crystalline material - Class 3 - than the smaller fluid energy milled material. The Class 3 material exhibits evidence of crystal cracking. Finally, we discuss this evidence and our attempt to correlate microstructural features to observed changes in continuum level initiation behavior.

  10. A Novel Melt Cast Composite Booster Formulation Based on DNTF/TNT/GAP-ETPE/Nano-HMX

    Directory of Open Access Journals (Sweden)

    Shuo Yu

    2016-01-01

    Full Text Available To obtain the melt cast booster explosive formulation with high energy and low critical detonation diameter, melt cast explosives were designed by 3,4-bis(3-nitrofurazan-4-ylfuroxan (DNTF/2,4,6-trinitrotoluene (TNT/glycidyl azide polymer-energetic thermoplastic elastomer (GAP-ETPE/nano-1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX/Aristowax. Furthermore, the impact sensitivity, small scale gap test, rheological properties, propagation reliability, and detonation velocity were measured and analyzed. The results show that when the mass ratio of DNTF/TNT/GAP-ETPE/nano-HMX/Aristowax is 34.2/22.8/2/40/1, not only does it indicate excellent rheological property but it has a brilliant safety performance as well. Moreover, it can propagate the detonation waves successfully in the groove at 0.7 mm × 0.7 mm. When the charge density in the groove is 1.70 g·cm−3, its detonation velocity can reach 7890 m·s−1.

  11. A working man`s analysis of incidents and accidents with explosives at the Los Alamos National Laboratory, 1946--1997

    Energy Technology Data Exchange (ETDEWEB)

    Ramsay, J.B.; Goldie, R.H.

    1998-12-31

    At the inception of the Laboratory hectic and intense work was the norm during the development of the atomic bombs. After the war the development of other weapons for the Cold War again contributed to an intense work environment. Formal Standard Operating Procedures (SOPs) were not required at that time. However, the occurrence of six fatalities in 1959 during the development of a new high-energy plastic bonded explosive (94% HMX) forced the introduction SOPs. After an accident at the Department of Energy (DOE) plant at Amarillo, TX in 1977, the DOE promulgated the Department wide DOE Explosives Safety Manual. Table 1 outlines the history of the introduction of SOPs and the DOE Explosives Safety Manual. Many of the rules and guidelines presented in these documents were developed and introduced as the result of an incident or accident. However, many of the current staff are not familiar with the background of the development. To preserve as much of this knowledge as possible, they are collecting documentation on incidents and accidents involving energetic materials at Los Alamos. Formal investigations of serious accidents elucidate the multiple causes that contributed to accidents. These reports are generally buried in a file and, and are not read by more recent workers. Reports involving fatalities at Los Alamos before 1974 were withheld from the general employee. Also, these documents contain much detail and analysis that is not of interest to the field worker. The authors have collected the documents describing 116 incidents and have analyzed the contributing factors as viewed from the standpoint of the individual operator. All the incidents occurred at the Los Alamos National Laboratory and involved energetic materials in some manner, though not all occurred within the explosive handling groups. Most accidents are caused by multiple contributing factors. They have attempted to select the one or two factors that they consider as the most important relative to the

  12. UPTAKE AND TRANSFORMATION OF EXPLOSIVES BY EASTERN COTTONWOOD (POPULUS DELTOIDES)

    Science.gov (United States)

    The explosives 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-tetraazocine (HMX) have been extensively used by the United States military to manufacture munitions. Since World War II, both the commissioning an...

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

    Energy Technology Data Exchange (ETDEWEB)

    Myers, L.C.

    1997-09-01

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

  14. A thermal-mechanical constitutive model for b-HMX single crystal and cohesive interface under dynamic high pressure loading

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Due to the significant thermal-mechanical effects during hot spot formation in PBX explosives,a thermodynamic constitutive model has been constructed for HMX anisotropic single crystal subjected to dynamic impact loading. The crystal plasticity model based on dislocation dynamics theory was employed to describe the anisotropic plastic behavior along the preferential slip systems. A modified equation of state (EOS) was introduced into the constitutive equations through the decomposing stress tensor and the nonlinear elasticity for materials was taken into account. The one-dimensional strain impact simulations for HMX single crystal and quasi-bicrystal were performed respectively,in which the cohesive elements were inserted over the interface areas for the latter. The predicted particle velocities for the single crystal sample agreed well with the experimental results in the literature. Furthermore,the effects of crystal orientations,interface,misorientations on localized strain,stress and temperature distributions were predicted and discussed.

  15. Optimized Synthesis of HMX Nanoparticles Using Antisolvent Precipitation Method

    Science.gov (United States)

    Kumar, Raj; Siril, Prem Felix; Soni, Pramod

    2015-10-01

    Nanoparticles of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) were prepared by an antisolvent precipitation method. The effect of different experimental parameters such as temperature of antisolvent and concentration of solution on particle size of nano-HMX was studied systematically. A higher temperature (70°C) of the antisolvent and lower concentration of HMX in acetone (5 mM) favored the formation of smaller particles. Average particle size ranged from 30 to 128 nm under different experimental conditions. Nano-HMX was characterized using dynamic light scattering (DLS), field emission scanning electron microscopy (FESEM), ultraviolet-visible spectrophotometry, powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric analysis coupled with differential scanning calorimetry (TGA-DSC). FTIR, XRD, and TGA-DSC studies revealed that the nano-HMX was in the β-polymorphic form.

  16. Modeling violent reaction following low speed impact on confined explosives

    Science.gov (United States)

    Curtis, John Philip; Jones, Andrew; Hughes, Christopher; Reaugh, John

    2012-03-01

    To ensure the safe storage and deployment of explosives it is important to understand the mechanisms that give rise to ignition and reaction growth in low speed impacts. The High Explosive Response to Mechanical Stimulus (HERMES) material model, integrated in the Lagrangian code LSDYNA, has been developed to model the progress of the reaction after such an impact. The low speed impact characteristics of an HMX based formulation have been examined using the AWE Steven Test. Axisymmetric simulations of an HMX explosive in the AWE Steven Test have been performed. A sensitivity study included the influence of friction, mesh resolution, and confinement. By comparing the experimental and calculated results, key model parameters which determine the explosive's response in this configuration have been identified. The model qualitatively predicts the point of ignition within the vehicle. Future refinements are discussed.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-10-01

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

  18. Explosive Materials Combustion by Heated Wires

    Directory of Open Access Journals (Sweden)

    I. V. Kondakov

    1999-07-01

    Full Text Available The knowledge of ignition parameters of explosive materials (EM presents both the definite scientific interest for developing the ignition kinetics models and the practical interest from the point of view of their danger assessment. The present investigations, as opposed to the known technique for EMs ignition temperature determination, have been performed by using the model explosive material samples of high density which have been produced on the basis of HMX and TATB. Applying the technique of firing ballistic powders by a heated wire, the EM ignition temperature depending on the time (rate of heating has been investigated. The technique makes it possible to calculate heat pulses and heat flows leading to ignition. By decreasing the heat flow, the time for the EM heating up to ignition increases and temperature falls thereby approaching the critical value, characterising the danger limit under accidents associated with heating. The ignition of EM based on HMX and TATB takes place in a different manner. With the EM on the basis of HMX and with great heat flows. The ignition beginning from the surface in the form of flash is typical but when achieving the critical parameters, the heated layer flash takes place that increases the probability of the explosion realisation. EM based on TATH always ignite in the form of combustion from the surface, independent of the heat flow that points to the higher extent of its safety. These data correlate well with the higher parameters of its ignition.

  19. The Influence of Thermal Conditions on the Thermomechanics of Particulate-Composite, Mock Explosive Samples under Near-Resonant Excitation

    OpenAIRE

    2016-01-01

    Vapor detection is one of the most effective ways to find hidden plastic-bonded explosives in the field today. In recent years, it has been demonstrated that providing near-resonant vibratory excitation to explosives dramatically increases their vapor pressure, allowing for easier detection. Unfortunately, there currently exists a limited understanding of the thermomechanics of energetic material. This study seeks to help fill this technical void by exploring the thermomechanics of mock plast...

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

    Science.gov (United States)

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

    2017-01-01

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

  1. DEFLAGRATION RATES OF SECONDARY EXPLOSIVES UNDER STATIC MPA - GPA PRESSURE

    Energy Technology Data Exchange (ETDEWEB)

    Zaug, J; Young, C; Long, G; Maienschein, J; Glascoe, E; Hansen, D; Wardell, J; Black, C; Sykora, G

    2009-07-30

    We provide measurements of the chemical reaction propagation rate (RPR) as a function of pressure using diamond anvil cell (DAC) and strand burner technologies. Materials investigated include HMX and RDX crystalline powders, LX-04 (85% HMX and 15% Viton A), and Composition B (63% RDX, 36% TNT, 1% wax). The anomalous correspondence between crystal structure, including in some instances isostructural phase transitions, on pressure dependent RPRs of HMX and RDX are correlated to confocal micro-Raman spectroscopic results. The contrast between DAC GPa and strand burner MPa regime measurements yield insight into explosive material burn phenomena. Here we highlight pressure dependent physicochemical mechanisms that appear to affect the deflagration rate of precompressed energetic materials.

  2. Dissociative Electron Attachment to the Nitroamine HMX (Octahydro-1,3,5,7-Tetranitro-1,3,5,7-Tetrazocine)

    CERN Document Server

    Postler, J; Matias, C; Mauracher, A; da Silva, F Ferreira; Scheier, P; Limão-Vieira, P; Denifl, S

    2016-01-01

    In the present study, dissociative electron attachment (DEA) measurements with gas phase HMX, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, $C_4H_8N_8O_8$, have been performed by means of a crossed electron-molecular beam experiment. The most intense signals are observed at 46 and 176u and assigned to $NO_{2}^{-}$ and $C_3H_6N_5O_{4}^{-}$, respectively. Anion efficiency curves for 15 negatively charged fragments have been measured in the electron energy region from about 0-20 eV with an energy resolution of ~0.7 eV. Product anions are observed mainly in the low energy region, near 0 eV, arising from surprisingly complex reactions associated with multiple bond cleavages and structural and electronic rearrangement. The remarkable instability of HMX towards electron attachment with virtually zero kinetic energy reflects the highly explosive nature of this compound. Substantially different intensity ratios of resonances for common fragment anions allow distinguishing the nitroamines HMX and royal demolition e...

  3. Corner-turning characteristics of TATB/HMX/Kel-F mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Stallings, T.L.; Osborn, A.G.; West, G.T.

    1983-01-01

    A factorial experiment was conducted to determine the effects of HMX content, HMX particle size and TATB particle size in TATB/HMX-Kel-F formulations containing 5% by weight Kel-F 800 binder on corner-turning performance at ambient and -54 C. TATB and HMX particle-size variations did not significantly affect differences in corner-turning performance between the two temperatures. With increasing HMX contents the effect of temperature on corner turning became less and at the maximum HMX content studied, 25%, the corner turning levels were almost equal at ambient and -54 C.

  4. The Dilution/Crystallization Kinetics of RDX and HMX

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Three thermokinetic equations describing the crystal growth process and two relationships between the parameters and the constants of the kinetic equations are derived. The thermokinetic data of crystal growth processes of RDX and HMX are treated based on the derived equations and relationships. The results show that the exothermic dilution / crystallization processes of RDX and HMX are the first order reaction and accord with the dislocation theory.

  5. Porous HMX initiation studies -- Sugar as an inert simulant

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-11-01

    For several years the authors have been using magnetic particle velocity gauges to study the shock loading of porous HMX (65 and 73% TMD) of different particle sizes to determine their compaction and initiation characteristics. Because it has been difficult to separate the effects of compaction and reaction, an inert simulant was needed with properties similar to HMX. Sugar was selected as the simulant for several reasons: (1) the particle size distribution of C and H granulated sugar is similar to the coarse HMX the authors have been using (120 {micro}m average size), (2) the particle size of C and H confectioners (powdered) sugar is similar to the fine HMX in the studies (10 {micro}m average size), (3) it is an organic material, and (4) sugar was readily available. Because the densities of HMX and sugar are somewhat different, the authors chose to do the experiments on sugar compacts at 65 and 73% TMD. As expected, no reaction was observed in the sugar experiments. Compaction wave profiles were similar to those measured earlier for the HMX, i.e., the compaction waves in the coarse sugar were quite disperse while those in the fine sugar were much sharper. This indicates that the compaction wave profiles are controlled by particle size and not reaction. Also, the coarse sugar gauge signals exhibited a great deal of noise, thought to the be result of fracto-emission.

  6. Force-Field Derivation and Atomistic Simulation of HMX/Graphite Interface and Polycrystal Systems

    Institute of Scientific and Technical Information of China (English)

    龙瑶; 刘永刚; 聂福德; 陈军

    2012-01-01

    Interface is the key issue to understand the performance of composite materials. In this work, we study the interface between octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and graphite, try to find out its contribution to mixture explosives. The work starts from the force-field derivation. We get ab initio based pair potentials across the interface, and then use them to study the interface structural and mechanical properties. A series of large scale molecular dynamics simulations are performed. The structure evolution, energy variation and elastic/plastic transformation of interface and polycrystal systems are calculated. The desensitizing mechanism of graphite to HMX is discussed.

  7. Elucidation of high sensitivity of δ-HMX: New insight from first principles simulations

    Science.gov (United States)

    Kuklja, Maija M.; Tsyshevsky, Roman V.; Sharia, Onise

    2017-01-01

    Understanding of a significant difference in sensitivities of β and δ phases of cyclotetramethylene-tetranitramine (HMX) has been long one of the challenges in the field of high energy density materials. Despite many experimental and theoretical efforts to explain the high sensitivity of the δ phase, convincing reasons behind the HMX behavior remained unclear. We established that the presence of a polar surface in δ-HMX has fundamental implications for stability and overall chemical behavior of the material. A comparative quantum-chemical analysis of decomposition mechanisms in polar δ-HMX and nonpolar β-HMX discovered a considerable difference in dominating dissociation reactions, activation barriers, and reaction rates. The polarization-induced charge transfer offered a logical explanation for different sensitivity of β-HMX and δ-HMX polymorphs to detonation initiation. Our conclusions also removed long-standing contradictions and explained a large range of experimental data on thermal decomposition of HMX.

  8. Deuterium Isotope Effects During HMX Combustion: Chemical Kinetic Burn Rate Control Mechanism Verified

    Science.gov (United States)

    1989-01-01

    propellant contain- controls the I-IMX burn rate in the pressure range cited. The ing a chemically modified double base ( CMDB ) high oxygen 1.41 KDIE...controlling the observed overall or global burn rate of the could expect from the deuterium labeled HMX methylene HMX/ CMDB composite propellant. It is...measured in the HMX/ CMDB system. A graphic representa- densed phase KDIE investigation of thermochemical decom- non of one cornposic HMX binder

  9. COMPARATIVE STUDY ON STRENGTH PROPERTIES OF WOOD PLASTIC BONDED BOARDS PRODUCED FROM COFFEE CHAFF AND CEIBA PENTANDRA SAWDUST

    Directory of Open Access Journals (Sweden)

    Kehinde Sesan AINA

    2016-03-01

    Full Text Available Strength properties of Wood Plastic-bonded Boards (WPBB of 10mm in thickness were produced in this study from two lignocellulosic materials coffee and recycled low density polyethylene (rLDPE as a binder. WPBB were produced from particles of coffee chaff and Ceiba pentandra, at three levels of mixing ratio (1:1, 2:1 and 3:1, and at three levels of board density (500, 600 and 700kgm-3 given the total treatment combinations of 18 respectively. Effects of lignocelluloses particles, mixing ratio (MR and board density (BD on flexural strength properties of the WPBB were investigated. The flexural strength of the WPBB range from 0.25 to 4.79N/mm2 and 891.00 to 16415.87N/mm2 for modulus of rupture (MOR and modulus of elasticity (MOE respectively. The statistically results shows that the main factor and interaction factors were significantly different at P≤0.05 level of probability. It was observed in this study that as the plastic content with density increased, flexural strength of the boards increases. The study showed that WPBB made from coffee chaff particles are stiffer and stronger than WPBBs made from Ceiba pentandra particles. Based on the outcome of the results in this study, coffee chaff could as well be used as filler in the polymer industry to produce stronger biopolymer composite for structural applications. This study would form a baseline strategy for further research efforts on production of composite from agro-residues wastes.

  10. Continuous wave laser irradiation of explosives

    Energy Technology Data Exchange (ETDEWEB)

    McGrane, Shawn D.; Moore, David S.

    2010-12-01

    Quantitative measurements of the levels of continuous wave (CW) laser light that can be safely applied to bare explosives during contact operations were obtained at 532 nm, 785 nm, and 1550 nm wavelengths. A thermal camera was used to record the temperature of explosive pressed pellets and single crystals while they were irradiated using a measured laser power and laser spot size. A visible light image of the sample surface was obtained before and after the laser irradiation. Laser irradiation thresholds were obtained for the onset of any visible change to the explosive sample and for the onset of any visible chemical reaction. Deflagration to detonation transitions were not observed using any of these CW laser wavelengths on single crystals or pressed pellets in the unconfined geometry tested. Except for the photochemistry of DAAF, TATB and PBX 9502, all reactions appeared to be thermal using a 532 nm wavelength laser. For a 1550 nm wavelength laser, no photochemistry was evident, but the laser power thresholds for thermal damage in some of the materials were significantly lower than for the 532 nm laser wavelength. No reactions were observed in any of the studied explosives using the available 300 mW laser at 785 nm wavelength. Tables of laser irradiance damage and reaction thresholds are presented for pressed pellets of PBX9501, PBX9502, Composition B, HMX, TATB, RDX, DAAF, PETN, and TNT and single crystals of RDX, HMX, and PETN for each of the laser wavelengths.

  11. Pilot-scale in situ bioremediation of HMX and RDX in soil pore water in Hawaii.

    Science.gov (United States)

    Payne, Zachary M; Lamichhane, Krishna M; Babcock, Roger W; Turnbull, Stephen J

    2013-10-01

    A nine-month in situ bioremediation study was conducted in Makua Military Reservation (MMR) in Oahu, Hawaii (USA) to evaluate the potential of molasses to enhance biodegradation of royal demolition explosive (RDX) and high-melting explosive (HMX) contaminated soil below the root zone. MMR has been in operation since the 1940's resulting in subsurface contamination that in some locations exceeds USEPA preliminary remediation goals for these chemicals. A molasses-water mixture (1 : 40 dilution) was applied to a treatment plot and clean water was applied to a control plot via seven flood irrigation events. Pore water samples were collected from 12 lysimeters installed at different depths in 3 boreholes in each test plot. The difference in mean concentrations of RDX in pore water samples from the two test plots was very highly significant (p nitrogen concentrations also differed significantly with treatment (p sensor (31 ft) within 5 days of application. Most of the molasses was consumed by soil microorganisms by about 13.5 feet below ground surface and treatment of deeper depths may require greater molasses concentrations and/or more frequent flood irrigation. Use of the bioremediation method described herein could allow the sustainable use of live fire training ranges by enhancing biodegradation of explosives in situ and preventing them from migrating to through the vadose zone to underlying ground water and off-site.

  12. Observation of sub-detonative responses in confined high density HMX-based PBXs

    Science.gov (United States)

    Cumming, Andrew; Wood, Andrew; Steward, Paul; Ottley, Philip; Gould, Peter; Lewtas, Ian

    2015-06-01

    This paper describes experiments and modelling aimed at understanding the behaviour of highly loaded (90%-95%) pressed HMX-based PBXs, when subjected to shock compression and ignition by means of distinct mechanical and thermal insults under confinement. In order to separate the role of the stimuli, a test has been designed where a metal impactor is propelled at test samples using a well characterised propellant over a range of velocities to produce various levels of mechanical damage. The impactor is then heated using a characterised pyrotechnic composition which ignites the mechanically damaged explosive. Tubes have been designed to examine the effect of confinement at burst pressures of 218.5MPa and 120MPa. The high confinement tubes employ polycarbonate windows and the low confinement tubes are manufactured from polycarbonate blocks to allow the reaction of the energetic material to be captured using high-speed video. Tests carried out using these tubes have given a good insight into the processes occurring. Modelling runs have predicted an oscillating compressive wave in the explosive and considerable damage at either end of the explosive column. The latter leads to potential deconsolidation once the donor charge has burnt out allowing increased burning and violence.

  13. The detonation parameters of high energy density explosive predicted with a new revised VLW EOS

    Energy Technology Data Exchange (ETDEWEB)

    Xinping, L.; Xiaohua, J. [Southwest Institut of Chemical Mat. Chengdu Sichuan (China); Xiong, W. [Xian Modern Chemistry Research Institute (China)

    1996-12-31

    Some new target explosive compounds whose detonation performance significantly exceeds that of HMX have been predicted with the new revised VLM equation of state, which includes up to the sixth viral term. The two different hypotheses have been used in the calculation; solid carbon exists in detonation products as graphite or as diamond. (authors) 10 refs.

  14. Data representation and feature selection for colorimetric sensor arrays used as explosives detectors

    DEFF Research Database (Denmark)

    Alstrøm, Tommy Sonne; Larsen, Jan; Kostesha, Natalie

    2011-01-01

    Within the framework of the strategic research project Xsense at the Technical University of Denmark, we are developing a colorimetric sensor array which can be useful for detection of explosives like DNT, TNT, HMX, RDX and TATP and identification of volatile organic compounds in the presence...

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    We present a colorimetric sensor array which is able to detect explosives such as DNT, TNT, HMX, RDX and TATP and identifying volatile organic compounds in the presence of water vapor in air. To analyze colorimetric sensors with statistical methods, a suitable representation of sensory readings...

  16. Burning rate for steel-cased, pressed binderless HMX

    Science.gov (United States)

    Fifer, R. A.; Cole, J. E.

    1980-01-01

    The burning behavior of pressed binderless HMX laterally confined in 6.4 mm i.d. steel cases was measured over the pressure range 1.45 to 338 MPa in a constant pressure strand burner. The measured regression rates are compared to those reported previously for unconfined samples. It is shown that lateral confinement results in a several-fold decrease in the regression rate for the coarse particle size HMX above the transition to super fast regression. For class E samples, confinement shifts the transition to super fast regression from low pressure to high pressure. These results are interpreted in terms of the previously proposed progressive deconsolidation mechanism. Preliminary holographic photography and closed bomb tests are also described. Theoretical one dimensional modeling calculations were carried out to predict the expected flame height (particle burn out distance) as a function of particle size and pressure for binderless HMX burning by a progressive deconsolidation mechanism.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  18. Techniques for the estimation of Heats of Explosion (HEX) using thermochemical codes

    Science.gov (United States)

    Fifer, Robert A.; Morris, Jeffrey B.

    1993-09-01

    Procedures are outlined for calculating the heats of explosion (HEX) of neat energetic materials or propellant/explosive formulations using thermochemical codes. The 'exact' method and three approximate techniques are described; the approximate techniques either eliminate the need to sum the internal energies of the predicted products, or eliminate the need to specify a freeze-out temperature. The various techniques are illustrated for HMX and a nitrocellulose/nitroglycerine (NC/NG) mixture.

  19. Ignition behavior of an aluminum-bonded explosive (ABX)

    Science.gov (United States)

    Hardin, D. Barrett; Zhou, Min; Horie, Yasuyuki

    2017-01-01

    We report the results of a study on the ignition behavior of a novel concept and design of a heterogeneous energetic material system called ABX, or aluminum-bonded explosives. The idea is to replace the polymeric binder in polymer-bonded explosives (PBX) with aluminum. The motivation of this study is that a new design may have several desirable attributes, including, among others, electrical conductivity, higher mechanical strength, enhanced integrity, higher energy content, and enhanced thermal stability at elevated temperatures. The analysis carried out concerns the replacement of the Estane binder in a HMX/Estane PBX by aluminum. The HMX volume fraction in the PBX and HMX is approximately 81%. 2D mesoscale simulations are carried out, accounting for elasticity, viscoelasticity, elasto-viscoplasticity, fracture, internal friction, and thermal conduction. Results show that, relative to the PBX, the aluminum bonded explosives (ABX) show significantly less heating and lower ignition sensitivity under the same loading conditions. The findings appear to confirm the expected promise of ABX as a next-generation heterogeneous energetic material system with more desirable attributes.

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

    Science.gov (United States)

    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. Ultrafast dynamic response of single crystal β-HMX

    Science.gov (United States)

    Zaug, Joseph M.; Armstrong, Michael R.; Crowhurst, Jonathan C.; Radousky, Harry B.; Ferranti, Louis; Swan, Raymond; Gross, Rick; Teslich, Nick E.; Wall, Mark A.; Austin, Ryan A.; Fried, Laurence E.

    2017-01-01

    We report results from ultrafast compression experiments conducted on β-HMX single crystals. Results consist of nominally 12 picosecond time-resolved wave profile data, (ultrafast time domain interferometry -TDI measurements), that were analyzed to determine high-velocity wave speeds as a function of piston velocity. TDI results are used to validate calculations of anisotropic stress-strain behavior of shocked loaded energetic materials. Our previous results derived using a 350 ps duration compression drive revealed anisotropic elastic wave response in single crystal β-HMX from (110) and (010) impact planes. Here we present results using a 1.05 ns duration compression drive with a 950 ps interferometry window to extend knowledge of the anisotropic dynamic response of β-HMX within eight microns of the initial impact plane. We observe two distinct wave profiles from (010) and three wave profiles from (010) impact planes. The (110) impact plane wave speeds typically exceed (010) impact plane wave speeds at the same piston velocities. The development of multiple hydrodynamic wave profiles begins at 20 GPa for the (110) impact plane and 28 GPa for the (10) impact plane. We compare our ultrafast TDI results with previous gun and plate impact results on β-HMX and PBX9501.

  2. Compressible Heating in the Condense Phase due to Pore Collapse in HMX

    Science.gov (United States)

    Zhang, Ju; Jackson, Thomas

    Axisymmetric pore collapse in HMX is studied numerically by solving multi-phase reactive Euler equations. The generation of hot spots in the condense phase due to compressible heating is examined. The motivation is to improve the understanding of the role of embedded cavities in the initiation of reaction in explosives, and to investigate the effect of hot spots in the condense phase due to compressible heating alone, complementing previous study on hot spots due to the reaction in the gas phase and at the interface. It is found that the shock-cavity interaction results in pressures and thus temperatures that are substantially higher than the post-shock values in the condense phase. However, these hot spots in the condense phase due to compressible heating alone do not seem to be sufficiently hot to lead to ignition at shock pressures of 1-3 GPa. Thus, compressible heating in the condense phase may be excluded as a mechanism for initiation of explosives. It should be pointed out that the ignition threshold for the temperature, the so-called ``switch-on'' temperature, of hot spots depend on chemistry kinetics parameters. Switch-on temperature is lower for faster reaction rate. The current chemistry kinetics parameters are based on previous experimental work. This work was supported in part by the Defense Threat Reduction Agency and by the U.S. Department of Energy.

  3. Explosives tester

    Science.gov (United States)

    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.

  4. A contribution to the knowledge of HMX decomposition and application of results. [at atmospheric pressure

    Science.gov (United States)

    Kraeutle, K. J.

    1980-01-01

    The decomposition of cyclotramethylenetetranitramine (HMX) in the solid and liquid phase was studied by isothermal and nonisothermal heating at atmospheric pressure. Decomposition rates of solid HMX changed with sample size and gaseous environment. Kinetic parameters were obtained from weight loss measurements in the temperature range 229 C - 269 C. These tests also yielded highly porous solid residues. Qualitative aspects of solid and liquid phase decomposition of HMX with additives were also investigated in isothermal and nonisothermal tests.

  5. Effect of HMX on the combustion response function

    Science.gov (United States)

    Strand, L. D.; Cohen, N. S.

    1980-01-01

    Over a pressure range of 3.5-7 MPa and a frequency range of 500-2000 Hz and compared to propellants having equivalent energy and burn rate, HMX produces less pressure-coupled acoustic driving than AP and is equivalent to NC/TMETN. Formation of carbonaceous combustion products indicates that binder decomposition does not follow equilibrium thermochemistry, and that this is aggravated by fuel richness or the absence of AP.

  6. Coating and Characterization of Mock and Explosive Materials

    Directory of Open Access Journals (Sweden)

    Emily M. Hunt

    2012-01-01

    Full Text Available This project develops a method of manufacturing plastic-bonded explosives by using use precision control of agglomeration and coating of energetic powders. The energetic material coating process entails suspending either wet or dry energetic powders in a stream of inert gas and contacting the energetic powder with atomized droplets of a lacquer composed of binder and organic solvent. By using a high-velocity air stream to pneumatically convey the energetic powders and droplets of lacquer, the energetic powders are efficiently wetted while agglomerate drying begins almost immediately. The result is an energetic powder uniformly coated with binder, that is, a PBX, with a high bulk density suitable for pressing. Experiments have been conducted using mock explosive materials to examine coating effectiveness and density. Energetic materials are now being coated and will be tested both mechanically and thermally. This allows for a comprehensive comparison of the morphology and reactivity of the newly coated materials to previously manufactured materials.

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

    Energy Technology Data Exchange (ETDEWEB)

    Harrier, Danielle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Andersen, Kyle Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    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

  8. The force-field derivation and application of explosive/additive interfaces

    Science.gov (United States)

    Long, Yao; Chen, Jun

    2016-10-01

    The inter-molecular force-field across RDX/(paraffin, fluoropolymer) interfaces are derived from first-principles calculated energies under the GGA+vdW functional. Based on the force-field, the polycrystal structures of mixture explosives are obtained, and a set of thermodynamic properties are calculated, including the elastic constants, thermal expansion coefficient, heat capacity, isothermal curve and the Hugoniot curve. The results are in good agreement with the available experiments, and provide a reasonable prediction about the properties of plastic bonded explosives. We find that the thermal expansion coefficient of a multi-component explosive is not only determined by the properties of the components, but is also affected by the thermal stress at the explosive/additive interfaces.

  9. Measurement of the flow properties within a copper tube containing a deflagrating explosive

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Larry G [Los Alamos National Laboratory; Morris, John S [Los Alamos National Laboratory; Jackson, Scott I [Los Alamos National Laboratory

    2009-01-01

    We report on the propagation of deflagration waves in the high explosive (HE) PBX 9501 (95 wt % HMX, 5 wt% binder). Our test configuration, which we call the def1agration cylinder test (DFCT), is fashioned after the detonation cylinder test (DTCT) that is used to calibrate the JWL detonation product equation of state (EOS). In the DFCT, the HE is heated to a uniform slightly subcritical temperature, and is ignited at one end by a hot wire. For some configurations and initial conditions, we observe a quasi-steady wave that flares the tube into a funnel shape, stretching it to the point of rupture. This behavior is qualitatively like the DTCT, such that, by invoking certain additional approximations that we discuss, its behavior can be analyzed by the same methods. We employ an analysis proposed by G.I. Taylor to infer the pressure-volume curve for the burning, expanding flow. By comparing this result to the EOS of HMX product gas alone. we infer that only {approx}20 wt% of the HMX has burned at tube rupture. This result confirms pre-existing observations about the role of convective burning in HMX cookoff explosions.

  10. Plasmonic enhanced terahertz time-domain spectroscopy system for identification of common explosives

    Science.gov (United States)

    Demiraǧ, Yiǧit; Bütün, Bayram; Özbay, Ekmel

    2017-05-01

    In this study, we present a classification algorithm for terahertz time-domain spectroscopy systems (THz-TDS) that can be trained to identify most commonly used explosives (C4, HMX, RDX, PETN, TNT, composition-B and blackpowder) and some non-explosive samples (lactose, sucrose, PABA). Our procedure can be used in any THz-TDS system that detects either transmission or reflection spectra at room conditions. After preprocessing the signal in low THz regime (0.1 - 3 THz), our algorithm takes advantages of a latent space transformation based on principle component analysis in order to classify explosives with low false alarm rate.

  11. Underground Explosions

    Science.gov (United States)

    2015-09-09

    underground explosions has led to significant progress in the development of geomechanics a science studying mechanical properties of rocks and rock...mining industry. One way to improve methods of fragmentation by explosives involves utilizing the geomechanical properties of the rock massif, in...Geomekhanika krupnomasshtabnykh vzryvov ( Geomechanics of large explosions), Nedra, Moscow, 319 pp. [This book in available in electronic format

  12. Ignition Prediction of Pressed HMX based on Hotspot Analysis Under Shock Pulse Loading

    Science.gov (United States)

    Kim, Seokpum; Miller, Christopher; Horie, Yasuyuki; Molek, Christopher; Welle, Eric; Zhou, Min

    The ignition behavior of pressed HMX under shock pulse loading with a flyer is analyzed using a cohesive finite element method (CFEM) which accounts for large deformation, microcracking, frictional heating, and thermal conduction. The simulations account for the controlled loading of thin-flyer shock experiments with flyer velocities between 1.7 and 4.0 km/s. The study focuses on the computational prediction of ignition threshold using James criterion which involves loading intensity and energy imparted to the material. The predicted thresholds are in good agreement with measurements from shock experiments. In particular, it is found that grain size significantly affects the ignition sensitivity of the materials, with smaller sizes leading to lower energy thresholds required for ignition. In addition, significant stress attenuation is observed in high intensity pulse loading as compared to low intensity pulse loading, which affects density of hotspot distribution. The microstructure-performance relations obtained can be used to design explosives with tailored attributes and safety envelopes.

  13. Elucidation of high sensitivity of δ-HMX: New insight from the first principle simulations

    Science.gov (United States)

    Kuklja, Maija; Sharia, Onise; Tsyshevsky, Roman

    2015-06-01

    Understanding of a tremendous difference in sensitivities of β and δ phases of cyclotetramethylene-tetranitramine (HMX) has been long one of the stubborn challenges in the field of high energy density materials. Despite many experimental and theoretical efforts to explain the high sensitivity of the δ phase, convincing reasons behind the HMX behavior remained puzzling. We established that the presence of a polar surface in δ-HMX has fundamental implications for stability and overall chemical behavior of the material. A comparative state-of-the-art quantum-chemical analysis of major decomposition mechanisms in polar δ-HMX and nonpolar β-HMX discovered a dramatic difference in dominating dissociation reactions, activation barriers, and reaction rates. The polarization-induced charge transfer offered a logical explanation for different sensitivity of β-HMX and δ-HMX polymorphs to detonation initiation. Our conclusions also removed long-standing contradictions and explained a large range of experimental data on thermal decomposition of HMX.

  14. CdS/Cu纳米光催化剂降解废水中的HMX和RDX试验研究%Photocatalytic Degradation of HMX and RDX Wastewater with CdS/Cu Nanophotocatalyst

    Institute of Scientific and Technical Information of China (English)

    Hamid Reza Pouretedal; Mohammad Hossien Keshavarz; Mohammad Hasan Yosefi; Arash Shokrollahi; Abbas Zali

    2008-01-01

    The wastewater with HMX and RDX was treated by photodegradation process in the presence of cadmium sulfide doped with copper as photocatalyst under UV and Vis irradiations. The influence on the degration of Cu% as dopant in CdS/Cu nanoparticles, pH of solution, dosage of photocatalyst and concentration of explosives were studied. The XRD patterns and UV-Vis spectra were used to characterize the nanoparticle. Results show that the degradation efficiency for HMX and RDX wastewater reaches 85%-88% in the presence of Cd0.95Cu0.05S under 180 min UV irradiation. The dosage of 160.0 mg·L-1 of photocatalyst and the pH of 7 are the optimum. A gradual decrease in degradation at the first two cycles is seen.

  15. Crystal structure and morphology of β-HMX in acetone: A molecular dynamics simulation and experimental study

    Indian Academy of Sciences (India)

    JUN TAO; XIAOFENG WANG

    2017-04-01

    Single crystals of β-Cyclotetramethylene tetranitramine (HMX) were prepared by the solvent evaporation method. The structure was then determined using infrared spectroscopy and single crystal X-ray diffraction. The modified attachment energy (AE) model was used to predict the morphologies of β-HMXin vacuum and in acetone. The morphology and sensitivity of HMX before and after recrystallization were characterized. The results of calculation showed that the (011) and (110) surfaces of β-HMX are of great morphologicalimportance. The predicted β-HMX morphology agreed qualitatively with the SEM result. The sensitivity results show that recrystallization in acetone can effectively reduce the impact and friction sensitivities of β-HMX.

  16. Application of a four-step HMX kinetic model to an impact-induced fraction ignition problems

    Energy Technology Data Exchange (ETDEWEB)

    Perry, William L [Los Alamos National Laboratory; Gunderson, Jake A [Los Alamos National Laboratory; Dickson, Peter M [Los Alamos National Laboratory

    2010-01-01

    There has been a long history of interest in the decomposition kinetics of HMX and HMX-based formulations due to the widespread use of this explosive in high performance systems. The kinetics allow us to predict, or attempt to predict, the behavior of the explosive when subjected to thermal hazard scenarios that lead to ignition via impact, spark, friction or external heat. The latter, commonly referred to as 'cook off', has been widely studied and contemporary kinetic and transport models accurately predict time and location of ignition for simple geometries. However, there has been relatively little attention given to the problem of localized ignition that results from the first three ignition sources of impact, spark and friction. The use of a zero-order single-rate expression describing the exothermic decomposition of explosives dates to the early work of Frank-Kamanetskii in the late 1930s and continued through the 60's and 70's. This expression provides very general qualitative insight, but cannot provide accurate spatial or timing details of slow cook off ignition. In the 70s, Catalano, et al., noted that single step kinetics would not accurately predict time to ignition in the one-dimensional time to explosion apparatus (ODTX). In the early 80s, Tarver and McGuire published their well-known three step kinetic expression that included an endothermic decomposition step. This scheme significantly improved the accuracy of ignition time prediction for the ODTX. However, the Tarver/McGuire model could not produce the internal temperature profiles observed in the small-scale radial experiments nor could it accurately predict the location of ignition. Those factors are suspected to significantly affect the post-ignition behavior and better models were needed. Brill, et al. noted that the enthalpy change due to the beta-delta crystal phase transition was similar to the assumed endothermic decomposition step in the Tarver/McGuire model. Henson, et

  17. Liquid explosives

    CERN Document Server

    Liu, Jiping

    2015-01-01

    The book drawing on the author's nearly half a century of energetic materials research experience intends to systematically review the global researches on liquid explosives. The book focuses on the study of the conception, explosion mechanism, properties and preparation of liquid explosives. It provides a combination of theoretical knowledge and practical examples in a reader-friendly style. The book is likely to be interest of university researchers and graduate students in the fields of energetic materials, blasting engineering and mining.

  18. Relationship between pressure and reaction violence in thermal explosions

    Science.gov (United States)

    Smilowitz, L.; Henson, B. F.; Rodriguez, G.; Remelius, D.; Baca, E.; Oschwald, D.; Suvorova, N.

    2017-01-01

    Reaction violence of a thermal explosion is determined by the energy release rate of the explosive and the coupling of that energy to the case and surroundings. For the HMX and TATB based secondary high explosives studied, we have observed that temperature controls the time to explosion and pressure controls the final energy release rate subsequent to ignition. Pressure measurements in the thermal explosion regime have been notoriously difficult to make due to the extreme rise in temperature which is also occurring during a thermal explosion. We have utilized several different pressure measurement techniques for several different secondary high explosives. These techniques include commercially available piezoelectric and piezoresistive sensors which we have utilized in the low pressure (sub 30 MPa) range of PBX 9502 thermal explosions, and fiber Bragg grating sensors for the higher pressure range (up to GPa) for PBX9501 experiments. In this talk, we will compare the measurement techniques and discuss the pressures measured for the different formulations studied. Simultaneous x-ray radiography measurements of burn velocity will also be shown and correlations between pressure, burn velocity, and reaction violence will be discussed.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2015-12-30

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

  1. Effect of viscoplasticity on ignition sensitivity of an HMX based PBX

    Science.gov (United States)

    Hardin, D. Barrett; Zhou, Min

    2017-01-01

    The effect of viscoplastic deformation of the energetic component (HMX) on the mechanical, thermal, and ignition responses of a two-phase (HMX and Estane) PBX is analyzed. PBX microstructures are subjected to impact loading from a constant velocity piston traveling at a rate of 50 to 200 m/s. The analysis uses a 2D cohesive finite element framework, the focus of which is to evaluate the relative ignition sensitivity of the materials to determine the effect of the viscoplasticity of HMX on the responses. To delineate this effect, two sets of calculations are carried out; one set assumes the HMX grains are fully hyperelastic, and the other set assumes the HMX grains are elastic-viscoplastic. Results show that PBX specimens with elastic-viscoplastic HMX grains experience lower average and peak temperature rises, and as a result, show lower numbers of hotspots. An ignition criterion based on a criticality threshold obtained from chemical kinetics is used to quantify the ignition behavior of the materials. The criterion focuses on hotspot size and temperature to determine if a hotspot will undergo thermal runaway. It is found that the viscoplasticity of HMX increases the minimum load duration, mean load duration, threshold loading velocity, and total input energy required for ignition.

  2. Effect of Viscoplasticity on Ignition Sensitivity of an HMX-Based PBX

    Science.gov (United States)

    Hardin, D. Barrett; Zhou, Min

    2015-06-01

    The effect of viscoplastic deformation of the energetic component (HMX) on the mechanical, thermal, and ignition responses of a two-phase (HMX and Estane) PBX is analyzed. PBX microstructures are subjected to impact loading from a constant velocity piston traveling at a rate of 50 to 200 m/s. The analysis uses a 2D cohesive finite element framework. The focus of is to evaluate the relative ignition sensitivity of the materials to determine the effect of the viscoplasticity of HMX on the responses. To delineate this effect, two sets of calculations are carried out, one set assumes the HMX grains are fully hyperelastic and the other set assumes the HMX grains are elastic-viscoplastic. Results show that PBX specimens with elastic-viscoplastic HMX grains experience lower average and peak temperature rises, and as a result, show lower numbers of hotspots. An ignition criterion based on a criticality threshold obtained from chemical kinetics is used to quantify the ignition behavior of the materials. The criterion focuses on hotspot size and temperature to determine if a hotspot will undergo thermal runaway. It is found that the viscoplasticity of HMX increases the minimum load duration, mean load duration, threshold loading velocity, and total input energy required for ignition.

  3. 炸药爆轰参数与空中爆炸冲击波超压的关系%Relation of Air Explosion Shock Wave Overpressure and Detonation Parameters of Explosives

    Institute of Scientific and Technical Information of China (English)

    牛余雷; 冯晓军; 李媛媛; 南海; 郭昕

    2013-01-01

    为研究炸药爆轰参数与空中爆炸冲击波超压之间的关系,设计了不同铝含量的RDX/Al、HMX/Al混合炸药,并进行了空中爆炸试验.根据爆炸相似理论,用相同条件下实测TNT超压数据,计算了冲击波超压的TNT当量.采用不同方法计算了炸药的爆轰参数.结果表明,炸药空中爆炸冲击波超压与爆热、爆容和爆速乘积TNT当量的1/3次方满足线性关系,且回归线在y轴上的截距为0,斜率与炸药的类型有关.对于TNT,斜率为1;对于RDX/Al混合炸药,斜率为1.053(R2 =0.9996);对HMX/Al混合炸药,斜率为1.073(R2 =0.9995),表明炸药的爆热、爆速和爆容对空中爆炸冲击波超压的影响相同.%To research the relation of air explosion shock wave overpressure and detonation parameters of explosives,the RDX-based and HMX-based composite explosives with different aluminum content were designed and the air explosion experiment was performed.Based on the explosion similarity law,the TNT equivalence of shock wave overpressure was calculated using TNT explosion overpressure data measured in the same condition.The detonation parameters of explosives were calculated by different methods.The results show that there is a linear relationship between TNT equivalence of air explosion shock wave overpressure and one-third power of the TNT equivalence for the product of the detonation heat,detonation volume and detonation velocity,and the intercept of regression at y-axis is zero.The slope relates to the types of explosive.The slope is 1 for TNT,1.053(R2 =0.9996)for RDX/Al composite explosives and 1.073 (R2 =0.9995)for HMX/Al composite explosives,indicating that the detonation heat,detonation volume and detonation velocity have the same influence on air explosion shock wave overpressure.

  4. Mouse H6 Homeobox 1 (Hmx1 mutations cause cranial abnormalities and reduced body mass

    Directory of Open Access Journals (Sweden)

    Munroe Robert J

    2009-04-01

    Full Text Available Abstract Background The H6 homeobox genes Hmx1, Hmx2, and Hmx3 (also known as Nkx5-3; Nkx5-2 and Nkx5-1, respectively, compose a family within the NKL subclass of the ANTP class of homeobox genes. Hmx gene family expression is mostly limited to sensory organs, branchial (pharyngeal arches, and the rostral part of the central nervous system. Targeted mutation of either Hmx2 or Hmx3 in mice disrupts the vestibular system. These tandemly duplicated genes have functional overlap as indicated by the loss of the entire vestibular system in double mutants. Mutants have not been described for Hmx1, the most divergent of the family. Results Dumbo (dmbo is a semi-lethal mouse mutation that was recovered in a forward genetic mutagenesis screen. Mutants exhibit enlarged ear pinnae with a distinctive ventrolateral shift. Here, we report on the basis of this phenotype and other abnormalities in the mutant, and identify the causative mutation as being an allele of Hmx1. Examination of dumbo skulls revealed only subtle changes in cranial bone morphology, namely hyperplasia of the gonial bone and irregularities along the caudal border of the squamous temporal bone. Other nearby otic structures were unaffected. The semilethality of dmbo/dmbo mice was found to be ~40%, occured perinatally, and was associated with exencephaly. Surviving mutants of both sexes exhibited reduced body mass from ~3 days postpartum onwards. Most dumbo adults were microphthalmic. Recombinant animals and specific deletion-bearing mice were used to map the dumbo mutation to a 1.8 Mb region on Chromosome 5. DNA sequencing of genes in this region revealed a nonsense mutation in the first exon of H6 Homeobox 1 (Hmx1; also Nkx5-3. An independent spontaneous allele called misplaced ears (mpe was also identified, confirming Hmx1 as the responsible mutant gene. Conclusion The divergence of Hmx1 from its paralogs is reflected by different and diverse developmental roles exclusive of vestibular

  5. Ignition of organic explosives by an electron beam

    Directory of Open Access Journals (Sweden)

    Ivanov Georgy A.

    2015-01-01

    Full Text Available A numerical simulation of the ignition of organic explosives (PETN, HMX, RDX, TATB with an electron beam was performed. A criterion for the ignition of energetic materials with a melting point below the temperature of ignition is obtained. The results of numerical calculations of the critical energy density of the electron beam are consistent with the criterion of ignition. Calculations of the critical energy density of PETN ignition in good agreement with the experiment. The most sensitive is PETN and the most heat-resistant is TATB.

  6. Comparison of visible and near-infrared Raman cross-sections of explosives in solution and in the solid state.

    Science.gov (United States)

    Emmons, Erik D; Guicheteau, Jason A; Fountain, Augustus W; Christesen, Steven D

    2012-06-01

    Raman cross-sections of explosives in solution and in the solid state have been measured using visible and near-infrared excitation via secondary calibration. These measurements are valuable for both fundamental scientific purposes and applications in the standoff detection of explosives. The explosive compounds RDX, HMX, TNT, 2,4-DNT, 2,6-DNT, and ammonium nitrate were measured using discrete excitation wavelengths ranging from 532 nm to 785 nm. A comparison of the spectral features and cross-sections between the solid state and solution was performed. Comparison is also made to cross-sections measured with deep ultraviolet excitation.

  7. Critical Shock Energy and Shock and Detonation Parameters of an Explosive

    Directory of Open Access Journals (Sweden)

    H. S. Yadav

    2009-07-01

    Full Text Available The present study deals with the connection between critical shock energy and detonation properties of an explosive. A relation for critical shock energy has been derived in terms of detonation velocity, width of reaction zone, initial density of the explosive, specific heat ratio of detonation products and either constants of linear relation between shock and particle velocity of the explosive or the constants of the Murnaghan’s type of equation of state of the explosive. These relations have been used to calculate the critical shock energy of RDX, HMX, RDX/TNT (60/40 and TNT explosives. The values of critical shock energies obtained in this study are in close agreement with those reported in the literature.Defence Science Journal, 2009, 59(4, pp.436-440, DOI:http://dx.doi.org/10.14429/dsj.59.1543

  8. Changes in Blow-Off Velocity Observed in Two Explosives at the Threshold for Sustained Ignition Using the Modified Gap Test

    Science.gov (United States)

    Lee, R. J.; Forbes, J. W.; Tasker, D. G.; Orme, R. S.

    2009-12-01

    The Modified Gap Test was used to quantify different levels of partial reaction for various input stresses. This test configuration has been historically useful in highlighting thresholds for first reaction, sustained ignition, and detonation. Two different HMX based compositions were studied; a cast-cured composition with 87% HMX and a pressed composition with 92% HMX. Each explosive was prepared from large industrially produced batches consisting of different unreactive polymeric binder systems. Short samples (50.8 mm in diameter and 12.7 mm thick) were shock loaded using the standard large-scale gap test donor system. Product-cloud blow-off velocities at the opposite end of the sample were measured using a high-speed digital-camera. Velocity versus input pres sure plots provided changes in reactivity that had developed by the 12.7 mm run distance. Results appear consistent for the lower input stresses. In contrast, the results varied widely in a range of input stresses around the transition to detonation in both explosives. These results indicate that both explosives are subject to large variation in blow-off velocity in a range of input stresses near the threshold for prompt detonation. This is explained by localized variations of HMX particle size and density in industrially prepared samples. Approved for public release, Distribution unlimited, IHDIV Log No. 09-108.

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

    Science.gov (United States)

    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.

  10. Novel signal-amplifying fluorescent nanofibers for naked-eye-based ultrasensitive detection of buried explosives and explosive vapors

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ying; La, Anthony; Ding, Yu; Liu, Yixin; Lei, Yu [Department of Chemical, Materials and Biomolecular Engineering, University of Connecticut, Storrs, CT (United States)

    2012-09-11

    A novel electrospun fluorescent nanofiberous membrane with a function like ''molecular wires'' was developed via electrospinning for the detection of ultra-trace nitro explosive vapors and buried explosives by naked eye under UV excitation. The high binding affinity between the electron-deficient nitro explosives and the sensing film results in a rapid, dramatic quenching in its fluorescence emission. A wide spectrum of nitro explosives, in particular, TNT, Tetryl, RDX, PETN and HMX could be ''visually'' detected at their sub-equilibrium vapors (less than 10 ppb, 74 ppt, 5 ppt, 7 ppt and 0.1 ppt, respectively) released from 1 ng explosives residues. Such outstanding sensing performance could be attributed to the proposed ''sandwich-like'' conformation between pyrene and phenyl pendants of PS which may allow efficient long-range energy migration similar to ''molecular wire'', thus achieving amplified fluorescence quenching. Its application for the detection of buried explosives in soil by naked eye was also demonstrated, indicating its potential application for landmine mapping. To the best of our knowledge, this is the first report about the detection of buried explosives without the use of any advanced analytical instrumentation. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Evaluation of phytoremediation for HMX at the Wainwright military base: greenhouse trials

    National Research Council Canada - National Science Library

    2000-01-01

    ... primarily to examine the fate of HMX in soil and plant tissues. Five plant species, including alfalfa (Medicago saliva), bush bean (Phaseolus vulgaris), canola (Brassica rapa), wheat (Triticum aestivum...

  12. Effect of Nitrate Ester on the Combustion Characteristics of PET/HMX -based Propellants

    National Research Council Canada - National Science Library

    Yunlan Sun; Baozhong Zhu; Shufen Li

    2011-01-01

    The effect of nitrate ester NG/TEGDN on the combustion characteristics of PET/HMX-based propellants has been experimentally investigated using of high-speed photography technique and scanning electron microscopy...

  13. Shock initiated thermal and chemical responses of HMX crystal from ReaxFF molecular dynamics simulation.

    Science.gov (United States)

    Zhou, Tingting; Song, Huajie; Liu, Yi; Huang, Fenglei

    2014-07-21

    To gain an atomistic-level understanding of the thermal and chemical responses of condensed energetic materials under thermal shock, we developed a thermal shock reactive dynamics (TS-RD) computational protocol using molecular dynamics simulation coupled with ReaxFF force field. β-Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) was selected as a a target explosive due to its wide usage in the military and industry. The results show that a thermal shock initiated by a large temperature gradient between the "hot" region and the "cold" region results in thermal expansion of the particles and induces a thermal-mechanical wave propagating back and forth in the system with an averaged velocity of 3.32 km s(-1). Heat propagating along the direction of thermal shock leads to a temperature increment of the system and thus chemical reaction initiation. Applying a continuum reactive heat conduction model combined with the temperature distribution obtained from the RD simulation, a heat conduction coefficient is derived as 0.80 W m(-1) K(-1). The chemical reaction mechanisms during thermal shock were analyzed, showing that the reaction is triggered by N-NO2 bond breaking followed by HONO elimination and ring fission. The propagation rates of the reaction front and reaction center are obtained to be 0.069 and 0.038 km s(-1), based on the time and spatial distribution of NO2. The pressure effect on the thermal shock was also investigated by employing uniaxial compression before the thermal shock. We find that compression significantly accelerates thermal-mechanical wave propagation and heat conduction, resulting in higher temperature and more excited molecules and thus earlier initiation and faster propagation of chemical reactions.

  14. Porous HMX initiation studies{emdash}sugar as an inert simulant

    Energy Technology Data Exchange (ETDEWEB)

    Sheffield, S.A.; Gustavsen, R.L.; Alcon, R.R. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    1998-07-01

    For several years we have been using magnetic particle velocity gauges to study the shock loading of porous HMX (65 and 73{percent} TMD) of different particle sizes to determine their compaction and initiation characteristics. Because it has been difficult to separate the effects of compaction and reaction, an inert simulant was needed with properties similar to HMX. Sugar was selected as the simulant for several reasons: 1) the particle size distribution of C & H granulated sugar is similar to the coarse HMX we have been using (120 {mu}m average size), 2) the particle size of C & H confectioners (powdered) sugar is similar to the fine HMX in the studies (10 {mu}m average size), 3) it is an organic material, and 4) sugar was readily available. Because the densities of HMX and sugar are somewhat different, we chose to do the experiments on sugar compacts at 65 and 73{percent} TMD. As expected, no reaction was observed in the sugar experiments. Compaction wave profiles were similar to those measured earlier for the HMX, i.e., the compaction waves in the coarse sugar were quite disperse while those in the fine sugar were much sharper. This indicates that the compaction wave profiles are controlled by particle size and not reaction. Also, the coarse sugar gauge signals exhibited a great deal of noise, thought to be the result of fracto-emission. {copyright} {ital 1998 American Institute of Physics.}

  15. Intermolecular Interaction of HMX:an Application of ONIOM Methodology

    Institute of Scientific and Technical Information of China (English)

    JU Xue-hai; BEI Feng-li; XIA Qi-ying; XIAO He-ming

    2004-01-01

    Ab initio calculations at the B3LYP/3-21G * *, HF/3-21G>** and ONIOM(HF/3-21G* * : AM1) levels of the theory in combination with counterpoise procedure for BSSE correction were performed on HMX dimers. There exist two O…H intermolecular contacts and the dispersion forces are dominant in the dimers.The corrected binding energies of the dimer are -15.10 and -17.81 kJ/mol at the HF/3-21G** and ONIOM(HF/3-21G**: AM1)levels, respectively. The calculation by the B3LYP method gives irrational corrected binding energies though it produces similar intermolecular distances as those produced by the HF or ONIOM method. The geometrical parameters, the contact distances and the binding energies demonstrated,for the first time, the validity of the ONIOM method applied in the calculation of the parameters of intermolecular interactions.

  16. Decomposition Kinetics for Mass Loss and Heat Released for HMX

    Energy Technology Data Exchange (ETDEWEB)

    Weese, R K; Burnham, A K

    2004-07-27

    Nucleation-growth kinetic expressions are derived for thermal decomposition of HMX from a variety of types of data, including mass loss for isothermal and constant rate heating in an open pan, and heat flow for isothermal and constant rate heating in open and closed pans. Conditions are identified in which thermal runaway is small to nonexistent, which typically means temperatures less than 255 C and heating rates less than 1 C/min. Activation energies are typically in the 140 to 150 kJ/mol regime for open pan experiments and about 160 kJ/mol for sealed pan experiments. The reaction clearly displays more than one process, and most likely three processes, which are most clearly evident in open pan experiments. The reaction is accelerated for closed pan experiments, and one global reaction appears to fit the data well.

  17. Laser-Induced Breakdown Spectroscopy for Detection of Explosives Residues: A Review of Recent Advances, Challenges, and Future Prospects

    Science.gov (United States)

    2013-04-01

    including highly purified RDX, cyclotetramethylene tetranitramine (HMX), trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), and nitrocellulose ...NC), and from operational explosives and propellants C-4, A-5, M-43, LX-14, and JA2 [22]. The observed LIBS spectra contained the expected C, H, N... Propellants , Explos Pyrotech 28:53–57 31. Gottfried JL, De Lucia Jr FC, Munson CA, Miziolek AW (2007) Spectrochim Acta B 62:1405–1411 32. Gottfried JL

  18. Sub-sonic thermal explosions investigated by radiography

    Energy Technology Data Exchange (ETDEWEB)

    Smilowitz, Laura B [Los Alamos National Laboratory; Henson, Bryan F [Los Alamos National Laboratory; Romero, Jerry J [Los Alamos National Laboratory; Asay, Blaine W [Los Alamos National Laboratory

    2010-01-01

    This paper reviews the past 5 years of experiments utilizing radiographic techniques to study defiagration in thermal explosions in HMX based formulations. Details of triggering and timing synchronization are given. Radiographic images collected using both protons and x-rays are presented. Comparisons of experiments with varying size, case confinement, binder, and synchronization are presented. Techniques for quantifying the data in the images are presented and a mechanism for post-ignition burn propagation in a thermal explosion is discussed. From these experiments, we have observed a mechanism for sub-sonic defiagration with both gas phase convective and solid phase conductive burning. The convective front velocity is directly measured from the radiographic images and consumes only a small fraction of the HE. It lights the HE as it passes beginning the slower solid state conductive burn process. This mechanism is used to create a model to simulate the radiographic results and a comparison will be shown.

  19. Calibration of the BKW--EOS and application to aluminized composite explosives

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, M.L.; Baer, M.R.

    1993-01-01

    The Becker-Kistiakowsky-Wilson equation of state (BKW-EOS) has been calibrated over a wide initial density range near C-J states using measured detonation properties from 62 explosives at III total initial densities. Values for the empirical BKW constants [alpha], [beta], [kappa], and [theta] were 0.5, 0.298, 10.5, and 6620, respectively. Covolumes were assumed to be invariant. Model evaluation includes comparison to measurements from 91 explosives composed of combinations of Al, B, Ba, C, Ca, Cl, F, H, N, 0, P, Pb, and Si at 147 total initial densities. Adequate agreement between predictions and measurements were obtained with a few exceptions for nonideal explosives. However, detonation properties for the nonideal explosives can be predicted adequately by assuming partial equilibrium. The partial equilibrium assumption was applied to aluminized composites of RDX, HMX, TNETB, and TNT to predict detonation velocity and temperature.

  20. Calibration of the BKW--EOS and application to aluminized composite explosives

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, M.L.; Baer, M.R.

    1993-04-01

    The Becker-Kistiakowsky-Wilson equation of state (BKW-EOS) has been calibrated over a wide initial density range near C-J states using measured detonation properties from 62 explosives at III total initial densities. Values for the empirical BKW constants {alpha}, {beta}, {kappa}, and {theta} were 0.5, 0.298, 10.5, and 6620, respectively. Covolumes were assumed to be invariant. Model evaluation includes comparison to measurements from 91 explosives composed of combinations of Al, B, Ba, C, Ca, Cl, F, H, N, 0, P, Pb, and Si at 147 total initial densities. Adequate agreement between predictions and measurements were obtained with a few exceptions for nonideal explosives. However, detonation properties for the nonideal explosives can be predicted adequately by assuming partial equilibrium. The partial equilibrium assumption was applied to aluminized composites of RDX, HMX, TNETB, and TNT to predict detonation velocity and temperature.

  1. Theoretical studies on the structures and detonation properties of nitramine explosives containing benzene ring.

    Science.gov (United States)

    Zhao, GuoZheng; Lu, Ming

    2012-06-01

    The nitramine compounds containing benzene ring were optimized to obtain their molecular geometries and electronic structures at DFT-B3LYP/6-31+G(d) level. The theoretical molecular density (ρ), heat of formation (HOF), energy gap (ΔE(LUMO-HOMO)), charge on the nitro group (-Q(NO2)), detonation velocity (D) and detonation pressure (P), estimated using Kamlet-Jacobs equations, showed that the detonation properties of these compounds were excellent. It is found that there are good linear relationships between density, heat of formation, detonation velocity, detonation pressure and the number of nitro group. The simulation results reveal that molecule G performs similarly to famous explosive HMX, and molecule H outperforms HMX. According to the quantitative standard of energetics as an HEDC (high energy density compound), molecule H essentially satisfies this requirement. These results provide basic information for molecular design of novel high energetic density compounds.

  2. Mechanisms of formation of trace decomposition products in complex high explosive mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Woodyard, J.D.; Burgess, C.E. [West Texas A and M Univ., Canyon, TX (United States); Rainwater, K.A. [Texas Tech Univ., Lubbock, TX (United States)

    1999-03-01

    A significant concern in the nation`s stockpile surveillance program in prediction of the lifetimes of the high explosives (HE) and their components as the weapons age. The Department of Energy`s Core Surveillance and Enhanced Surveillance programs specifically target issues of degradation of HE, binders, and plastic-bonded explosives (PBX) for determination of component lifetimes and handling procedures. These material science topics are being addressed at the DOE national laboratories and production plants, including Pantex. The principal goal of this project is to identify the mechanisms of decomposition of HE, plasticizers, plastic polymer binders, and radical stabilizers resulting from exposures to ionizing radiation, heat, and humidity. The following reports the work completed for 1998, including a comprehensive literature review about some of the materials examined and the laboratory work completed to date. The materials focused on in the laboratory are TATB, Estane 5301, and Irganox 1010.

  3. Niche explosion.

    Science.gov (United States)

    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.

  4. Explosive Start

    Institute of Scientific and Technical Information of China (English)

    FRANCISCO; LITTLE

    2006-01-01

    I ducked involuntarily as the first set of explosions went off and made my way in double time to the street corner, where I had spotted an arcade that could be used for shelter. Running quickly in a crouched, military maneuver while inhaling gunpowder fumes, I was totally oblivious to the laughter and head-shaking coming

  5. Analysis of microstructure-dependent shock dissipation and hot-spot formation in granular metalized explosive

    Science.gov (United States)

    Chakravarthy, Sunada; Gonthier, Keith A.

    2016-07-01

    Variations in the microstructure of granular explosives (i.e., particle packing density, size, shape, and composition) can affect their shock sensitivity by altering thermomechanical fields at the particle-scale during pore collapse within shocks. If the deformation rate is fast, hot-spots can form, ignite, and interact, resulting in burn at the macro-scale. In this study, a two-dimensional finite and discrete element technique is used to simulate and examine shock-induced dissipation and hot-spot formation within low density explosives (68%-84% theoretical maximum density (TMD)) consisting of large ensembles of HMX (C4H8N8O8) and aluminum (Al) particles (size ˜ 60 -360 μm). Emphasis is placed on identifying how the inclusion of Al influences effective shock dissipation and hot-spot fields relative to equivalent ensembles of neat/pure HMX for shocks that are sufficiently strong to eliminate porosity. Spatially distributed hot-spot fields are characterized by their number density and area fraction enabling their dynamics to be described in terms of nucleation, growth, and agglomeration-dominated phases with increasing shock strength. For fixed shock particle speed, predictions indicate that decreasing packing density enhances shock dissipation and hot-spot formation, and that the inclusion of Al increases dissipation relative to neat HMX by pressure enhanced compaction resulting in fewer but larger HMX hot-spots. Ensembles having bimodal particle sizes are shown to significantly affect hot-spot dynamics by altering the spatial distribution of hot-spots behind shocks.

  6. Experimental measurements of the detonation wave profile in a TATB based explosive

    Directory of Open Access Journals (Sweden)

    Decaris L.

    2011-01-01

    Full Text Available We report results of the experimental measurements of the detonation wave profile of the TATB based plastic bonded explosive T2 (97 w. % of TATB using VISAR and Heterodyne Velocimetry (HV – same as Photon Doppler Velocimetry. The experiment consists in initiating a detonation wave in a 15 mm diameter cylinder of explosive using an explosive wire detonator and an explosive booster. In order to obtain the particle velocity history in the reaction zone, we measure particle velocity at the interaction of the detonation front with an aluminized window or the free surface velocity of a metallic foil. Lithium Fluoride (LIF, PMMA and steel have been tested. Several shots have been performed for different lengths of explosive. We compare the VISAR and HV measurements. With LIF and steel, VISAR and HV diagnostics give very similar profiles. The ZND profile obtained on LIF is resolved with both techniques. With PMMA, HV gives a more accurate profile than VISAR in the reaction zone. There is no evidence of the influence of the explosive cylinder length.

  7. Ultrasensitive optoelectronic sensors for nitrogen oxides and explosives detection

    Science.gov (United States)

    Wojtas, J.; Bielecki, Z.; Stacewicz, T.; Mikolajczyk, J.

    2013-01-01

    The article describes application of cavity enhanced absorption spectroscopy (CEAS) for detection of nitrogen oxides and vapours of explosives. The oxides are important greenhouse gases that are of large influence on environment, living organisms and human health. These compounds are also markers of some human diseases as well as they are emitted by commonly used explosives. Therefore sensitive nitrogen oxides sensors are of great importance for many applications, e. g. for environment protection (air monitoring), for medicine investigation (analyzing of exhaled air) and finally for explosives detection. In the Institute of Optoelectronics MUT different types of optoelectronic sensors employing CEAS were developed. They were designed to measure trace concentration of nitrogen dioxide, nitric oxide, and nitrous oxide. The sensors provide opportunity for simultaneous measurement of these gases concentration at ppb level. Their sensitivity is comparable with sensitivities of instruments based on other methods, e.g. gas chromatography or mass spectrometry. Our sensors were used for some explosives detection as well. The experiment showed that the sensors provide possibility to detect explosive devices consisting of nitroglycerine, ammonium nitrate, TNT, PETN, RDX and HMX.

  8. Microparticle Formation and Crystallization Rate of HMX with Supercritical CO2 Antisolvent Recrystallization

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Microparticle formation and crystallization rate of 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX) in acetone solution using supercritical carbon dioxide antisolvent (GAS) recrystallization were studied. Scanning electronic microscopy, X-ray diffraction and infrared radiation were used to examine particle size, crystallinity and chemical structure. The results show that β-HMX microparticle in different average size (2-9.5μm) and with narrow size distribution were obtained by controlling the expansibility, expansion speed, initial concentration and temperature during recrystallization of HMX. The formation of nuclei may be a main cause of consumption of solute when the solution is expanded rapidly enough and the equilibrium concentration is lower, in which almost monodisperse microparticle can be obtained.

  9. Microparticle Formation and Crystallization Rate of HMX with Supercritical CO2 Antisolvent Recrystallization

    Institute of Scientific and Technical Information of China (English)

    蔡建国; 周展云; 邓修

    2001-01-01

    Microparticle formation and crystallization rate of 1,3,5,7-tetranitro-l,3,5,7-tetraazacyclooctane (HMX) in acetone solution using supercritical carbon dioxide antisolvent (GAS) recrystallization were studied. Scanning electronic microscopy, X-ray diffraction and infrared radiation were used to examine particle size, crystallinity and chemical structure. The results show that β-HMX microparticle in different average size (2--9.5μm) and with narrow size distribution were obtained by controlling the expansibility, expansion speed, initial concentration and temperature during recrystallization of HMX. The formation of nuclei may be a main cause of consumption of solute when the solution is expanded rapidly enough and the equilibrium concentration is lower, in which almost monodisperse microparticle can be obtained.

  10. Analysis of compaction shock interactions during DDT of low density HMX

    Science.gov (United States)

    Rao, Pratap T.; Gonthier, Keith A.

    2017-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-05-29

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

  12. Surface Polarity Of Beta-hmx Crystal And The Related Adhesive Forces With Estane Binder

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lu [Los Alamos National Laboratory; Hanson, David E [Los Alamos National Laboratory

    2008-01-01

    Here we present the results on the study of surface properties of {beta}-HMX crystal utilizing molecular simulations. The surface polarity of three principal crystal surfaces are investigated by measuring the water contact angles. The calculated contact angles agree excellently with the values measured by experiment and show that the surface polarity of three crystal surfaces are different. The free energies and forces of detaching an Estane chain with and without nitroplasticizer from the three principal crystal surfaces were calculated using umbrella sampling technique. We find that the detaching free energy/force increases with the increasing HMX surface polarity. In addition, our results also show that nitroplasticizer plays an important role in the adhesion forces between Estane and HMX surfaces.

  13. The role and importance of porosity in the deflagration rates of HMX-based materials

    Energy Technology Data Exchange (ETDEWEB)

    Glascoe, E A; Hsu, P C; Springer, H K

    2011-03-15

    The deflagration behavior of thermally damaged HMX-based materials will be discussed. Strands of material were burned at pressures ranging from 10-300 MPa using the LLNL high pressure strand burner. Strands were heated in-situ and burned while still hot; temperatures range from 90-200 C and were chosen in order to allow for thermal damage of the material without significant decomposition of the HMX. The results indicate that multiple variables affect the burn rate but the most important are the polymorph of HMX and the nature and thermal stability of the non-HE portion of the material. Characterization of the strands indicate that the thermal soak produces significant porosity and permeability in the sample allowing for significantly faster burning due to the increased surface area and new pathways for flame spread into the material. Specifically, the deflagration rates of heated PBXN-9, LX-10, and PBX-9501 will be discussed and compared.

  14. Critical analysis of nitramine decomposition data: Activation energies and frequency factors for HMX and RDX decomposition

    Science.gov (United States)

    Schroeder, M. A.

    1980-01-01

    A summary of a literature review on thermal decomposition of HMX and RDX is presented. The decomposition apparently fits first order kinetics. Recommended values for Arrhenius parameters for HMX and RDX decomposition in the gaseous and liquid phases and for decomposition of RDX in solution in TNT are given. The apparent importance of autocatalysis is pointed out, as are some possible complications that may be encountered in interpreting extending or extrapolating kinetic data for these compounds from measurements carried out below their melting points to the higher temperatures and pressure characteristic of combustion.

  15. Biodegradation of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) by Phanerochaete chrysosporium: new insight into the degradation pathway.

    Science.gov (United States)

    Fournier, Diane; Halasz, Annamaria; Thiboutot, Sonia; Ampleman, Guy; Manno, Dominic; Hawari, Jalal

    2004-08-01

    Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) is a recalcitrant energetic chemical that tends to accumulate in soil, close to the surface. The present study describes the aerobic biodegradability of HMX using Phanerochaete chrysosporium. When added to 7 day old static P. chrysosporium liquid cultures, HMX (600 nmol) degraded within 25 days of incubation. The removal of HMX was concomitant with the formation of transient amounts of its mono-nitroso derivative (1-NO-HMX). The latter apparently degraded via two potential routes: the first involved N-denitration followed by hydrolytic ring cleavage, and the second involved alpha-hydroxylation prior to ring cleavage. The degradation of 1-NO-HMX gave the ring-cleavage product 4-nitro-2,4-diazabutanal (NDAB), nitrite (NO2 -), nitrous oxide (N2O), and formaldehyde (HCHO). Using [14C]-HMX, we obtained 14CO2 (70% in 50 days), representing three C atoms of HMX. Incubation of real soils, contaminated with either HMX (403 micromol kg(-1)) (military base soil) or HMX (3057 micromol kg(-1)), and RDX (342 micromol kg(-1)) (ammunition soil) with the fungus led to 75 and 19.8% mineralization of HMX (liberated 14CO2), respectively, also via the intermediary formation of 1-NO-HMX. Mineralization in the latter soil increased to 35% after the addition of glucose, indicating that a fungus-based remediation process for heavily contaminated soils is promising. The present findings improve our understanding about the degradation pathway of HMX and demonstrate the utility of using the robust and versatile fungus P. chrysosporium to develop effective remediation processes for the removal of HMX.

  16. Explosive Pleuritis

    Directory of Open Access Journals (Sweden)

    Jasdeep K Sharma

    2001-01-01

    Full Text Available The objective of the present paper is to describe the clinical and computed tomography features of 'explosive pleuritis', an entity first named by Braman and Donat in 1986, and to propose a case definition. A case report of a previously healthy, 45-year-old man admitted to hospital with acute onset pleuritic chest pain is presented. The patient arrived at the emergency room at 15:00 in mild respiratory distress; the initial chest x-ray revealed a small right lower lobe effusion. The subsequent clinical course in hospital was dramatic. Within 18 h of admission, he developed severe respiratory distress with oxygen desaturation to 83% on room air and dullness of the right lung field. A repeat chest x-ray, taken the morning after admission, revealed complete opacification of the right hemithorax. A computed tomography scan of the thorax demonstrated a massive pleural effusion with compression of pulmonary tissue and mediastinal shift. Pleural fluid biochemical analysis revealed the following concentrations: glucose 3.5 mmol/L, lactate dehydrogenase 1550 U/L, protein 56.98 g/L, amylase 68 U/L and white blood cell count 600 cells/mL. The pleural fluid cultures demonstrated light growth of coagulase-negative staphylococcus and viridans streptococcus, and very light growth of Candida albicans. Cytology was negative for malignant cells. Thoracotomy was performed, which demonstrated a loculated parapneumonic effusion that required decortication. The patient responded favourably to the empirical administration of intravenous levofloxacin and ceftriaxone, and conservative surgical methods in the management of the empyema. This report also discusses the patient's rapidly progressing pleural effusion and offers a potential case definition for explosive pleuritis. Explosive pleuritis is a medical emergency defined by the rapid development of a pleural effusion involving more than 90% of the hemithorax over 24 h, which causes compression of pulmonary tissue and

  17. Explosive Pleuritis

    Directory of Open Access Journals (Sweden)

    Satish Kumar

    2012-01-01

    Full Text Available Pleural effusions associated with pneumonia (parapneumonic effusions are one of the most common causes of exudative pleural effusions in the world. Approximately 20 to 40% of patients hospitalized with pneumonia will have an accompanying pleural effusion. The term 'Explosive pleuritis' was originally described by Braman and Donat in 1986 as pleural effusions developing within hours of admission. We report a 38 years old male patient with minimal pleural effusion which progressed rapidly within one day to involve almost whole of the hemithorax. There were multiple loculations on ultrasonography of thorax. Pleural fluid was sero-sanguinous and revealed gram positive diplococcic. The patient improved with antibiotics and pigtail catheter drainage.

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

    Science.gov (United States)

    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.

  19. Changes in Run Distance Observed in two explosives at the threshold for sustained ignition using the Modified Gap Test

    Science.gov (United States)

    Lee, Richard; Forbes, Jerry; Tasker, Douglas; Orme, Rebecca

    2009-06-01

    The Modified Gap Test was used to quantify different levels of partial reaction for various input stresses. This test configuration has been historically useful in highlighting thresholds for first reaction, sustained ignition, and detonation. Two different HMX based compositions were studied; a cast-cured composition with 88% HMX and a pressed composition with 92% HMX. The final ingredients of each comprised different unreactive polymeric binder systems. Short samples (50.8 mm in diameter and 12.7 mm thick) were shock loaded using the standard large scale gap test donor system. Product-cloud blow-off velocities at the opposite end of the sample were measured using a high-speed digital-camera. Velocity versus input pressure plots provided changes in reactivity that had developed by the 12.7 mm run distance. Results were fairly consistent for the lower input pressures. In contrast, the results varied widely in a range of input stresses around the transition threshold for sustained ignition in both explosives. These results indicate that both explosives are subject to variation in run to detonation distance in a range of input stresses just prior to prompt detonation.

  20. A Hot Spots Ignition Probability Model for Low-Velocity Impacted Explosive Particles Based on the Particle Size and Distribution

    Directory of Open Access Journals (Sweden)

    Hong-fu Guo

    2017-01-01

    Full Text Available Particle size and distribution play an important role in ignition. The size and distribution of the cyclotetramethylene tetranitramine (HMX particles were investigated by Laser Particle Size Analyzer Malvern MS2000 before experiment and calculation. The mean size of particles is 161 μm. Minimum and maximum sizes are 80 μm and 263 μm, respectively. The distribution function is like a quadratic function. Based on the distribution of micron scale explosive particles, a microscopic model is established to describe the process of ignition of HMX particles under drop weight. Both temperature of contact zones and ignition probability of powder explosive can be predicted. The calculated results show that the temperature of the contact zones between the particles and the drop weight surface increases faster and higher than that of the contact zones between two neighboring particles. For HMX particles, with all other conditions being kept constant, if the drop height is less than 0.1 m, ignition probability will be close to 0. When the drop heights are 0.2 m and 0.3 m, the ignition probability is 0.27 and 0.64, respectively, whereas when the drop height is more than 0.4 m, ignition probability will be close to 0.82. In comparison with experimental results, the two curves are reasonably close to each other, which indicates our model has a certain degree of rationality.

  1. Ab Initio Calculations of the N-N Bond Dissociation for the Gas-phase RDX and HMX

    Science.gov (United States)

    Liu, Lin-Lin; Liu, Pei-Jin; Hu, Song-Qi; He, Guo-Qiang

    2017-01-01

    NO2 fission is a vital factor for 1,3,5-Trinitroperhydro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) decomposition. In this study, the geometry of the gas-phase RDX and HMX molecules was optimized, and the bond order and the bond dissociation energy of the N-N bonds were examined. Moreover, the rate constants of the gas-phase RDX and HMX conformers, concerning the N-N bond dissociation, were evaluated using the microcanonical variational transition state theory (μVT). The calculation results have shown that HMX is more stable than RDX in terms of the N-N bond dissociation, and the conformers stability parameters were as follows: RDXaaa HMX I HMX II. In addition, for the RDX conformers, the N-N bond of the pseudo-equatorial positioning of the nitro group was more stable than the N-N bond of the axial positioning of the nitro group, while the results were opposite in the case of the HMX conformers. Moreover, it has been shown that the dissociation rate constant of the N-N bond is influenced by the temperature significantly, thus the rate constants were much lower (<10-10 s-1) when the temperature was less than 1000 K.

  2. Prediction of explosive cylinder tests using equations of state from the PANDA code

    Energy Technology Data Exchange (ETDEWEB)

    Kerley, G.I. [Sandia National Labs., Albuquerque, NM (United States); Christian-Frear, T.L. [RE/SPEC, Inc., Albuquerque, NM (United States)

    1993-09-28

    The PANDA code is used to construct tabular equations of state (EOS) for the detonation products of 24 explosives having CHNO compositions. These EOS, together with a reactive burn model, are used in numerical hydrocode calculations of cylinder tests. The predicted detonation properties and cylinder wall velocities are found to give very good agreement with experimental data. Calculations of flat plate acceleration tests for the HMX-based explosive LX14 are also made and shown to agree well with the measurements. The effects of the reaction zone on both the cylinder and flat plate tests are discussed. For TATB-based explosives, the differences between experiment and theory are consistently larger than for other compositions and may be due to nonideal (finite dimameter) behavior.

  3. Initiation of Heated PBX-9501 Explosive When Exposed to Dynamic Loading

    Energy Technology Data Exchange (ETDEWEB)

    Urtiew, P A; Vandersall, K S; Tarver, C M; Garcia, F

    2005-08-16

    Shock initiation experiments on the heated PBX9501 explosive (95% HMX, 2.5% estane, and 2.5% nitro-plasticizer by weight) were performed at temperatures 150 C and 180 C to obtain in-situ pressure gauge data. A 101 mm diameter propellant driven gas gun was utilized to initiate the PBX9501 explosive and manganin piezo-resistive pressure gauge packages were placed between sample slices to measure time resolved local pressure histories. The run-distance-to-detonation points on the Pop-plot for these experiments showed the sensitivity of the heated material to shock loading. This work shows that heated PBX-9501 is more shock sensitive than it is at ambient conditions. Proper Ignition and Growth modeling parameters were obtained to fit the experimental data. This parameter set will allow accurate code predictions to be calculated for safety scenarios involving PBX9501 explosives at temperatures close to those at which experiments were performed.

  4. Leidenfrost explosions

    CERN Document Server

    Moreau, F; Dorbolo, S

    2012-01-01

    We present a fluid dynamics video showing the behavior of Leidenfrost droplets composed by a mixture of water and surfactant (SDS, Sodium Dodecyl sulfate). When a droplet is released on a plate heated above a given temperature a thin layer of vapor isolates the droplet from the plate. The droplet levitates over the plate. This is called the Leidenfrost effect. In this work we study the influence of the addition of a surfactant on the Leidenfrost phenomenon. As the droplet evaporates the concentration of SDS rises up to two orders of magnitude over the Critical Micelle Concentration (CMC). An unexpected and violent explosive behavior is observed. The video presents several explosions taken with a high speed camera (IDT-N4 at 30000 fps). All the presented experiments were performed on a plate heated at 300{\\deg}C. On the other hand, the initial quantity of SDS was tuned in two ways: (i) by varying the initial concentration of SDS and (ii) by varying the initial size of the droplet. By measuring the volume of th...

  5. HMX/DMF溶剂化物结构和分子间相互作用的理论研究%Theoretical Investigation on Structure and Intermolecular Interaction for HMX/ DMF Solvate

    Institute of Scientific and Technical Information of China (English)

    段晓惠; 于海利; 陈杰; 李洪珍

    2012-01-01

    采用量子化学计算和分子动力学(MD)模拟,研究了溶剂化物环四亚甲基四硝胺(HMX)/N,N-二甲基甲酰胺(DMF)的结构和分子间相互作用.对浸渍在DMF溶剂中的β-HMX分子的MD模拟表明,HMX的分子构象已经从β转变为α相.在MP2/6-31G*水平上的理论计算也说明,在DMF溶剂中,α-HMX比β-HMX更稳定.这解释了在HMX/DMF溶剂化物的多晶型中,所有的HMX分子均呈α构象的原因.采用MP2/6-31 G*方法,对α-HMX和DMF分子间可能的同型和异型二聚体进行结构优化.结果表明,组分间存在C—H…O氢键相互作用,并且α-HMX/DMF的稳定化能非常接近α-HMX/αα-HMX,并远远大于DMF二聚体的.这意味着异型分子间力可和同型分子间力竞争.从热力学的观点来看,共结晶过程可能发生.对α-HMX在DMF中的过饱和溶液的MD模拟表明,分子间相互作用对共结晶有利.这些理论研究对理解在HMX的DMF溶液中为什么发生的是共结晶而不是重结晶提供了有价值的信息.%The structures and intermolecular interactions for octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)/N,N-dimethylformamide (DMF) solvate have been investigated through quantum chemistry calculations and molecular dynamics (MD) simulations.MD simulation for a β-HMX molecule immersed in DMF solvent shows that β conformation has been transformed into α form.Theoretical calculations at the MP2/6-31G* level also indicate that the α HMX is more stable thanβ-HMX in DMF solution.This explains why all HMX molecules present α-form in the polymorphic forms of HMX/DMF solvate.Geometrical optimizations at-the level of MP2/6-31G* are performed for all the possible homodimers and heterodimers between α-HMX and DMF. Results reveal that C—H…O hydrogen bond interactions exist between components. Moreover,the stabilization energy of α-HMX/DMF is very close to that of α-HMX/α-HMX and much larger than that of DMF dimer.This means that the heteromeric

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

    Science.gov (United States)

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

    2016-07-14

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

  7. On the reliability of sensitivity test methods for submicrometer-sized RDX and HMX particles

    NARCIS (Netherlands)

    Radacsi, N.; Bouma, R.H.B.; Krabbendam-La Haye, E.L.M.; Horst, J.H. ter; Stankiewicz, A.I.; Heijden, A.E.D.M. van der

    2013-01-01

    Submicrometer-sized RDX and HMX crystals were produced by electrospray crystallization and submicrometer-sized RDX crystals were produced by plasma-assisted crystallization. Impact and friction sensitivity tests and ballistic impact chamber tests were performed to determine the product sensitivity.

  8. Coefficient of Thermal Expansion of the Beta and Delta Polymorphs of HMX

    Energy Technology Data Exchange (ETDEWEB)

    Weese, R K; Burnham, A K; Maienschein, J L

    2004-08-05

    Dimensional changes related to temperature cycling of the beta and delta polymorphs of HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) are important for a variety of applications. The coefficient of thermal expansion (CTE) of the beta and delta phases are measured and reported in this work over a temperature range of -20 C to 215 C. In addition, dimensional changes associated with the phase transition were measured, both through the transition and back down. Initially, differential scanning calorimetry (DSC) was used to investigate back conversion of the delta phase to the beta phase polymorph. The most successful approach was first to measure the amount of the beta to delta conversion, then after a given cooling period a repeat analysis, to measure the heat consumed by a second pass through the beta to delta phase transition. In addition, TMA is used to measure the dimensional change of a 0.20-gram sample of HMX during its initial heating and then three days later during a 2nd heating. This HMX shows the beta to delta phase transition a second time, thereby confirming the back conversion from delta to beta phase HMX.

  9. On the reliability of sensitivity test methods for submicrometer-sized RDX and HMX particles

    NARCIS (Netherlands)

    Radacsi, N.; Bouma, R.H.B.; Krabbendam-La Haye, E.L.M.; Horst, J.H. ter; Stankiewicz, A.I.; Heijden, A.E.D.M. van der

    2013-01-01

    Submicrometer-sized RDX and HMX crystals were produced by electrospray crystallization and submicrometer-sized RDX crystals were produced by plasma-assisted crystallization. Impact and friction sensitivity tests and ballistic impact chamber tests were performed to determine the product sensitivity.

  10. PETN, RDX, HMX, TATB: band gap dependence on pressure under hydrostatic compression from DFT with GW and vdW corrections

    Science.gov (United States)

    Mukhanov, Andrei; Yanilkin, Alexei

    2014-03-01

    In the middle of 1990s Gilman (Gilman J. J. 1995 Phil. Mag. B, 71:6, 1057) proposed the idea that explosives transit from insulator to conductor state with following adiabatic expansion of free electrons in shockwave. One of the reasons of such a behavior of electrons is narrowing or disappearing of the fundamental band gap in explosive single crystal. It is well known that similar behavior can be simulated by DFT. But there is a severe problem of lowering the value of gap by DFT. So for quantitative prediction of narrowing of gap under pressure it is necessary to use more complicated methods like GW. From first principle calculations we determined elastic moduli for ideal crystals of PETN, RDX, HMX, and TATB. Accounting for those moduli we simulated the 0 K isotherms for hydrostatic compression of single crystal. Due to the essential role of van der Waals interaction in such materials the vdW corrections to DFT in Grimme's form was used. We obtained the dependencies for band gap on pressure under hydrostatic compression. Our preliminary results on GW calculations show that for TATB at initial uncompressed volume we have the value of gap twice a bigger in GW than in DFT.

  11. MESOSCALE MODELING OF DEFLAGRATION-INDUCED DECONSOLIDATION IN POLYMER-BONDED EXPLOSIVES

    Energy Technology Data Exchange (ETDEWEB)

    Springer, H K; Glascoe, E A; Reaugh, J E; Kercher, J R; Maienschein, J L

    2011-08-01

    Initially undamaged polymer-bonded explosives can transition from conductive burning to more violent convective burning via rapid deconsolidation at higher pressures. The pressure-dependent infiltration of cracks and pores, i.e., damage, by product gases at the burn-front is a key step in the transition to convective burning. However, the relative influence of pre-existing damage and the evolution of deflagration-induced damage during the transition to convective burning is not well understood. The objective of this study is to investigate the role of microstructure and initial pressurization on deconsolidation. We performed simulations using the multi-physics hydrocode, ALE3D. HMX-Viton A served as our model explosive. A Prout-Tompkins chemical kinetic model, Vielle's Law pressure-dependent burning, Gruneisen equation-of-state, and simplified strength model were used for the HMX. The propensity for deconsolidation increased with increasing defect size and decreasing initial pressurization, as measured by the increase in burning surface area. These studies are important because they enable the development of continuum-scale damage models and the design of inherently safer explosives.

  12. Explosive Formulation Pilot Plant

    Data.gov (United States)

    Federal Laboratory Consortium — The Pilot Plant for Explosive Formulation supports the development of new explosives that are comprised of several components. This system is particularly beneficial...

  13. Chaotic Explosions

    CERN Document Server

    Altmann, Eduardo G; Tél, Tamás

    2015-01-01

    We investigate chaotic dynamical systems for which the intensity of trajectories might grow unlimited in time. We show that (i) the intensity grows exponentially in time and is distributed spatially according to a fractal measure with an information dimension smaller than that of the phase space,(ii) such exploding cases can be described by an operator formalism similar to the one applied to chaotic systems with absorption (decaying intensities), but (iii) the invariant quantities characterizing explosion and absorption are typically not directly related to each other, e.g., the decay rate and fractal dimensions of absorbing maps typically differ from the ones computed in the corresponding inverse (exploding) maps. We illustrate our general results through numerical simulation in the cardioid billiard mimicking a lasing optical cavity, and through analytical calculations in the baker map.

  14. Analysis of thermomechanical response of polycrystalline HMX under impact loading through mesoscale simulations

    Directory of Open Access Journals (Sweden)

    D. B. Hardin

    2014-09-01

    Full Text Available We investigate the response of polycrystalline HMX (Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine under impact loading through a 3-dimensional mesoscale model that explicitly accounts for anisotropic elasticity, crystalline plasticity, and heat conduction. This model is used to quantify the variability in temperature and stress fields due to random distributions of the orientations of crystalline grains in HMX under the loading scenarios considered. The simulations carried out concern the response of fully dense HMX polycrystalline ensembles under impact loading at imposed boundary velocities from 50 to 400 m/s. The polycrystalline ensemble studied consists of a geometrically arranged distribution of bi-modally sized and shaped grains. To quantify the effect of crystalline slip, two models with different numbers of available slip systems are used, reflecting differing characterizations of the slip systems of the HMX molecular crystal in the literature. The effects of microstructure and anisotropy on the distribution of heating and stress evolution are investigated. The results obtained indicate that crystalline response anisotropy at the microstructure level plays an important role in influencing both the overall response and the localization of stress and temperature. The overall longitudinal stress is up to 16% higher and the average temperature rise is only half in the material with fewer potential slip systems compared to those in the material with more available slip systems. Local stresses can be as high as twice the average stresses. The results show that crystalline anisotropy induces significant heterogeneities in both mechanical and thermal fields that previously have been neglected in the analyses of the behavior of HMX-based energetic materials.

  15. HERMES: A Model to Describe Deformation, Burning, Explosion, and Detonation

    Energy Technology Data Exchange (ETDEWEB)

    Reaugh, J E

    2011-11-22

    performance, whether as a result of accident, hazard, or a fault in the detonation train. These models describe the build-up of detonation from a shock stimulus. They are generally consistent with the mesoscale picture of ignition at many small defects in the plane of the shock front and the growth of the resulting hot-spots, leading to detonation in heterogeneous explosives such as plastic-bonded explosives (PBX). The models included terms for ignition, and also for the growth of reaction as tracked by the local mass fraction of product gas, {lambda}. The growth of reaction in such models incorporates a form factor that describes the change of surface area per unit volume (specific surface area) as the reaction progresses. For unimolecular crystalline-based explosives, the form factor is consistent with the mesoscale picture of a galaxy of hot spots burning outward and eventually interacting with each other. For composite explosives and propellants, where the fuel and oxidizer are segregated, the diffusion flame at the fuel-oxidizer interface can be interpreted with a different form factor that corresponds to grains burning inward from their surfaces. The form factor influences the energy release rate, and the amount of energy released in the reaction zone. Since the 19th century, gun and cannon propellants have used perforated geometric shapes that produce an increasing surface area as the propellant burns. This helps maintain the pressure as burning continues while the projectile travels down the barrel, which thereby increases the volume of the hot gas. Interior ballistics calculations use a geometric form factor to describe the changing surface area precisely. As a result, with a suitably modified form factor, detonation models can represent burning and explosion in damaged and broken reactant. The disadvantage of such models in application to accidents is that the ignition term does not distinguish between a value of pressure that results from a shock, and the same

  16. HERMES: A Model to Describe Deformation, Burning, Explosion, and Detonation

    Energy Technology Data Exchange (ETDEWEB)

    Reaugh, J E

    2011-11-22

    performance, whether as a result of accident, hazard, or a fault in the detonation train. These models describe the build-up of detonation from a shock stimulus. They are generally consistent with the mesoscale picture of ignition at many small defects in the plane of the shock front and the growth of the resulting hot-spots, leading to detonation in heterogeneous explosives such as plastic-bonded explosives (PBX). The models included terms for ignition, and also for the growth of reaction as tracked by the local mass fraction of product gas, {lambda}. The growth of reaction in such models incorporates a form factor that describes the change of surface area per unit volume (specific surface area) as the reaction progresses. For unimolecular crystalline-based explosives, the form factor is consistent with the mesoscale picture of a galaxy of hot spots burning outward and eventually interacting with each other. For composite explosives and propellants, where the fuel and oxidizer are segregated, the diffusion flame at the fuel-oxidizer interface can be interpreted with a different form factor that corresponds to grains burning inward from their surfaces. The form factor influences the energy release rate, and the amount of energy released in the reaction zone. Since the 19th century, gun and cannon propellants have used perforated geometric shapes that produce an increasing surface area as the propellant burns. This helps maintain the pressure as burning continues while the projectile travels down the barrel, which thereby increases the volume of the hot gas. Interior ballistics calculations use a geometric form factor to describe the changing surface area precisely. As a result, with a suitably modified form factor, detonation models can represent burning and explosion in damaged and broken reactant. The disadvantage of such models in application to accidents is that the ignition term does not distinguish between a value of pressure that results from a shock, and the same

  17. A Fast Liquid Chromatography Tandem Mass Spectrometric Analysis of PETN (Pentaerythritol Tetranitrate), RDX (3,5-Trinitro-1,3,5-triazacyclohexane) and HMX (Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) in Soil, Utilizing a Simple Ultrasonic-Assisted Extraction with Minimum Solvent.

    Science.gov (United States)

    Anilanmert, Beril; Aydin, Muhammet; Apak, Resat; Avci, Gülfidan Yenel; Cengiz, Salih

    2016-01-01

    Direct analyses of explosives in soil using liquid chromatography tandem mass spectrometry (LC-MS/MS) methods are very limited in the literature and require complex procedures or relatively high amount of solvent. A simple and rapid method was developed for the determination of pentaerythritol tetranitrate (PETN), 3,5-trinitro-1,3,5-triazacyclohexane (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), which are among the explosives used in terrorist attacks. A one-step extraction method for 1.00 g soil with 2.00 mL acetonitrile, and a 8-min LC-MS/MS method was developed. The detection limits for PETN, RDX and HMX were 5.2, 8.5 and 3.4 ng/g and quantitation limits were 10.0, 24.5, 6.0 ng/g. The intermediate precisions and Horwitz Ratio's were between 4.10 - 13.26% and 0.24 - 0.98, in order. This method was applied to a model post-blast debris collected from an artificial explosion and real samples collected after a terrorist attack in Istanbul. The method is easy and fast and requires less solvent use than other methods.

  18. Chemical profiling of explosives

    NARCIS (Netherlands)

    Brust, G.M.H.

    2014-01-01

    The primary goal of this thesis is to develop analytical methods for the chemical profiling of explosives. Current methodologies for the forensic analysis of explosives focus on identification of the explosive material. However, chemical profiling of explosives becomes increasingly important, as

  19. Supernova explosions

    CERN Document Server

    Branch, David

    2017-01-01

    Targeting advanced students of astronomy and physics, as well as astronomers and physicists contemplating research on supernovae or related fields, David Branch and J. Craig Wheeler offer a modern account of the nature, causes and consequences of supernovae, as well as of issues that remain to be resolved. Owing especially to (1) the appearance of supernova 1987A in the nearby Large Magellanic Cloud, (2) the spectacularly successful use of supernovae as distance indicators for cosmology, (3) the association of some supernovae with the enigmatic cosmic gamma-ray bursts, and (4) the discovery of a class of superluminous supernovae, the pace of supernova research has been increasing sharply. This monograph serves as a broad survey of modern supernova research and a guide to the current literature. The book’s emphasis is on the explosive phases of supernovae. Part 1 is devoted to a survey of the kinds of observations that inform us about supernovae, some basic interpreta tions of such data, and an overview of t...

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

    Energy Technology Data Exchange (ETDEWEB)

    An Chunjiang [Department of Environmental Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Faculty of Engineering and Applied Science, University of Regina, Regina, Saskatchewan, S4S 0A2 (Canada); He Yanling [Department of Environmental Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Huang Guohe, E-mail: gordon.huang@uregina.ca [Faculty of Engineering and Applied Science, University of Regina, Regina, Saskatchewan, S4S 0A2 (Canada); Sino-Canada Research Academy of Energy and Environmental Studies, North China Electric Power University, Beijing 102206 (China); Liu Yonghong [Department of Environmental and Chemical Engineering, Xi' an Polytechnic University, Xi' an 710048 (China)

    2010-07-15

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

  1. On shock initiation of heated explosives%受热炸药的冲击起爆特征

    Institute of Scientific and Technical Information of China (English)

    陈朗; 刘群; 伍俊英

    2013-01-01

    设计了炸药驱动飞片起爆受热炸药的实验装置,该装置既能够对实验炸药进行均匀地加热,又能够避免高温对加载炸药的影响.利用设计的实验装置对PBXC10炸药(HMX/TATB复合炸药)进行了14、100、140、160和180℃等5种不同加热温度下的冲击起爆实验,测量了该炸药内部压力的成长历程.采用点火增长反应速率方程对PBXC10炸药冲击起爆进行了数值模拟.根据实验结果,标定了不同温度下PBXC10炸药的点火增长模型参数,并给出了模型参数随温度变化的关系式,获得了不同温度下炸药的Pop关系.研究结果表明:PBXC10炸药的冲击波感度随温度的升高而升高,但与HMX炸药相比,其冲击波感度对温度的敏感性明显降低,这是因为PBXC10炸药中的TATB具有较好的降感作用.%An experimental device with an explosive-driven flyer plate was designed for shock initiation of the explosives at elevated temperatures. This device can heat up the acceptor explosives uniformly and keep the donor explosives out of the heating. Based on this device, the shock initiation tests were conducted for the HMX/TATB composite explosive heated to different temperatures: 14, 100, 140, 160 as well as 180 *C , and the in-situ pressure histories were measured at various depths of the explosives. The ignition and growth reaction rate equation was used to numerically simulate the shock initiation of the explosive. Based on the experimental results, the parameters were determined for the ignition and growth reaction rate equation of the explosive shock initiation at different temperatures, the relationships were given between the model parameters and temperature, and the Pop relationships of the explosive at different temperatures were given. The results show that the shock sensitivity of the HMX/TATB composite explosive increases with an increase in the temperature, but its dependence on temperature is less than that of the HMX explosive in

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

    Directory of Open Access Journals (Sweden)

    A. Puiu

    2012-01-01

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

  3. A first-principles investigation into the hydrogen bond interaction in β-HMX

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A theoretical study of structural and electronic properties of β-HMX crystal is performed using density-functional theory(DFT). The total density of states(TDOS) is presented. The atomic orbit projected density of state(PDOS) from the p-type orbit of C,N,O and the s-type orbit of H is discussed. The study by analyzing the PDOS shows that the structure of β-HMX crystal possesses C-H···O intra- and inter-molecular hydrogen-bonding. There exists a hydrogen bonding between H5 -1s and O12 -2p orbits,between H19 -1s and O28 -2p orbits of intra molecules,and between H19 -1s and O24 -2p orbits of inter molecules. The Mulliken population analysis is also made.

  4. Understanding vented gas explosions

    Energy Technology Data Exchange (ETDEWEB)

    Lautkaski, R. [VTT Energy, Espoo (Finland). Energy Systems

    1997-12-31

    The report is an introduction to vented gas explosions for nonspecialists, particularly designers of plants for flammable gases and liquids. The phenomena leading to pressure generation in vented gas explosions in empty and congested rooms are reviewed. The four peak model of vented gas explosions is presented with simple methods to predict the values of the individual peaks. Experimental data on the external explosion of dust and gas explosions is discussed. The empirical equation relating the internal and external peak pressures in vented dust explosions is shown to be valid for gas explosion tests in 30 m{sup 3} and 550 m{sup 3} chambers. However, the difficulty of predicting the internal peak pressure in large chambers remains. Methods of explosion relief panel design and principles of vent and equipment layout to reduce explosion overpressures are reviewed. (orig.) 65 refs.

  5. Time-sequenced X-ray Observation of a Thermal Explosion

    Energy Technology Data Exchange (ETDEWEB)

    Tringe, J W; Molitoris, J D; Smilowitz, L; Kercher, J R; Springer, H K; Henson, B F; Glascoe, E A; Greenwood, D W; Garza, R G; Wong, B M; Batteux, J D; Maienschein, J L

    2009-08-03

    The evolution of a thermally-initiated explosion is studied using a multiple-image x-ray system. HMX-based PBX 9501 is used in this work, enabling direct comparison to recently-published data obtained with proton radiography [1]. Multiple x-ray images of the explosion are obtained with image spacing of ten microseconds or more. The explosion is simultaneously characterized with a high-speed camera using an interframe spacing of 11 {micro}s. X-ray and camera images were both initiated passively by signals from an embedded thermocouple array, as opposed to being actively triggered by a laser pulse or other external source. X-ray images show an accelerating reacting front within the explosive, and also show unreacted explosive at the time the containment vessel bursts. High-speed camera images show debris ejected from the vessel expanding at 800-2100 m/s in the first tens of {micro}s after the container wall failure. The effective center of the initiation volume is about 6 mm from the geometric center of the explosive.

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

    Energy Technology Data Exchange (ETDEWEB)

    Sollier, A., E-mail: arnaud.sollier@cea.fr [CEA, DAM, DIF, 91297 Arpajon (France); Bouyer, V.; Hébert, P.; Doucet, M. [CEA, DAM, Le Ripault, 37260 Monts (France)

    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.

  7. Role of soil organic carbon and colloids in sorption and transport of TNT, RDX and HMX in training range soils.

    Science.gov (United States)

    Sharma, Prasesh; Mayes, Melanie A; Tang, Guoping

    2013-08-01

    Contamination of soils and groundwater by munitions compounds (MCs) is of significant concern at many U.S. Department of Defense sites. Soils were collected from operational training ranges in Maryland (APG), Massachusetts (MMR-B and MMR-E) and Washington (JBLM) and sorption and transport studies were conducted to investigate the effects of soil organic carbon (OC) and textural clay content on fate of dissolved MCs (TNT, RDX, HMX). Sorption experiments showed higher distribution coefficients [TNT:42-68 L kg(-1), RDX:6.9-8.7 L kg(-1) and HMX:2.6-3.1 L kg(-1)] in OC rich soils (JBLM, MMR-E) compared to clay rich soils (MMR-B and APG) [TNT:19-21 L kg(-1), RDX:2.5-3.4 L kg(-1), HMX:0.9-1.2 L kg(-1)]. In column experiments, breakthrough of MCs was faster in MMR-B and APG compared to MMR-E and JBLM soils. Among TNT, RDX and HMX, breakthrough was fastest for RDX followed by HMX and TNT for all columns. Defining the colloidal fraction as the difference between unfiltered samples and samples filtered with a 3 kDa filter, ~36%, ~15% and ~9% of TNT, RDX and HMX were found in the colloidal fraction in the solutions from sorption experiments, and around 20% of TNT in the effluent from the transport experiments. Results demonstrate that OC rich soils may enhance sorption and delay transport of TNT, RDX and HMX compared to clay-rich soils. Further, transport of TNT may be associated with soil colloid mobilization.

  8. 78 FR 64246 - Commerce in Explosives; List of Explosives Materials

    Science.gov (United States)

    2013-10-28

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF JUSTICE Bureau of Alcohol, Tobacco, Firearms, and Explosives Commerce in Explosives; List of Explosives Materials AGENCY: Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF); Department of Justice. ACTION:...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Distribution and Fate of Military Explosives and Propellants in Soil: A Review

    Directory of Open Access Journals (Sweden)

    John Pichtel

    2012-01-01

    Full Text Available Energetic materials comprise both explosives and propellants. When released to the biosphere, energetics are xenobiotic contaminants which pose toxic hazards to ecosystems, humans, and other biota. Soils worldwide are contaminated by energetic materials from manufacturing operations; military conflict; military training activities at firing and impact ranges; and open burning/open detonation (OB/OD of obsolete munitions. Energetic materials undergo varying degrees of chemical and biochemical transformation depending on the compounds involved and environmental factors. This paper addresses the occurrence of energetic materials in soils including a discussion of their fates after contact with soil. Emphasis is placed on the explosives 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, and the propellant ingredients nitroglycerin (NG, nitroguanidine (NQ, nitrocellulose (NC, 2,4-dinitrotoluene (2,4-DNT, and perchlorate.

  11. Totally confined explosive welding

    Science.gov (United States)

    Bement, L. J. (Inventor)

    1978-01-01

    The undesirable by-products of explosive welding are confined and the association noise is reduced by the use of a simple enclosure into which the explosive is placed and in which the explosion occurs. An infrangible enclosure is removably attached to one of the members to be bonded at the point directly opposite the bond area. An explosive is completely confined within the enclosure at a point in close proximity to the member to be bonded and a detonating means is attached to the explosive. The balance of the enclosure, not occupied by explosive, is filled with a shaped material which directs the explosive pressure toward the bond area. A detonator adaptor controls the expansion of the enclosure by the explosive force so that the enclosure at no point experiences a discontinuity in expansion which causes rupture. The use of the technique is practical in the restricted area of a space station.

  12. Cell phone explosion.

    Science.gov (United States)

    Atreya, Alok; Kanchan, Tanuj; Nepal, Samata; Pandey, Bhuwan Raj

    2016-03-01

    Cell phone explosions and resultant burn injuries are rarely reported in the scientific literature. We report a case of cell phone explosion that occurred when a young male was listening to music while the mobile was plugged in for charging.

  13. NEW EXPLOSIVE WELDING TECHNIQUES

    OpenAIRE

    Lotous, V.; Dragobetskii, V.

    2015-01-01

    Purpose - analysis of the variety of factors of the physical phenomena accompanying the process of the power explosive effect for development of new processes of metal treatment: explosive film coating of hardening and updating of a superficial layer of an item. Industrial approbation of cladding techniques by explosion of item surfaces of complex configuration and determination of parameters of the process of the explosive welding of high-strength pig-iron (graphite of the spherical form) wi...

  14. Photoacoustic Sensing of Explosives

    Science.gov (United States)

    2013-11-01

    NOV 2013 2. REPORT TYPE 3. DATES COVERED 00-00-2013 to 00-00-2013 4. TITLE AND SUBTITLE Photoacoustic Sensing of Explosives 5a. CONTRACT NUMBER...2013www.ll.mit.edu Photoacoustic Sensing of Explosives (PHASE) is a promising new technology that detects trace explosive residues from significant... photoacoustic phenomena resulting from ultraviolet laser excitation. Exposed explosives are excited up to 100 meters away by using PHASE’s

  15. Inspection tester for explosives

    Science.gov (United States)

    Haas, Jeffrey S.; Simpson, Randall L.; Satcher, Joe H.

    2007-11-13

    An inspection tester that can be used anywhere as a primary screening tool by non-technical personnel to determine whether a surface contains explosives. It includes a body with a sample pad. First and second explosives detecting reagent holders and dispensers are operatively connected to the body and the sample pad. The first and second explosives detecting reagent holders and dispensers are positioned to deliver the explosives detecting reagents to the sample pad. A is heater operatively connected to the sample pad.

  16. Explosive Line Wave Generators

    Science.gov (United States)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  18. Desorption and Transformation of Nitroaromatic (TNT) and Nitramine (RDX and HMX) Explosive Residues on Detonated Pure Mineral Phases

    Science.gov (United States)

    2011-11-01

    temperature of 825°C) and vermiculite dehydroxilization (110°C; Justo et al. 1993). None of the other samples exhibited changes in their X-ray...ranges. Chemosphere, 63, 1280–1290. Justo , A., Pérez-Rodríguez, J. L., & Sánchez-Soto, P. J. (1993). Thermal study of vermiculites and mica-vermiculite

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

    Science.gov (United States)

    2006-07-31

    both on nutrient agar 2.3% (Difco, Sparks,MD)and on yeastextract agar 2.0% (Difco). Inoculated Petri dishes were incubated for 2 weeks at 37 °C...2000) A genomics approach to the comprehensive analysis of the glutathione S-transferase gene family in soybean and maize . Plant Physiol 124

  20. New Mix Explosives for Explosive Welding

    Science.gov (United States)

    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.

  1. Monte Carlo calculations of the physical properties of RDX, {beta}-HMX, and TATB

    Energy Technology Data Exchange (ETDEWEB)

    Sewell, T.D.

    1997-09-01

    Atomistic Monte Carlo simulations in the NpT ensemble are used to calculate the physical properties of crystalline RDX, {beta}-HMX, and TATB. Among the issues being considered are the effects of various treatments of the intermolecular potential, inclusion of intramolecular flexibility, and simulation size dependence of the results. Calculations of the density, lattice energy, and lattice parameters are made over a wide range of pressures; thereby allowing for predictions of the bulk and linear coefficients of isothermal expansion of the crystals. Comparison with experiment is made where possible.

  2. Explosives tester with heater

    Science.gov (United States)

    Del Eckels, Joel [Livermore, CA; Nunes, Peter J [Danville, CA; Simpson, Randall L [Livermore, CA; Whipple, Richard E [Livermore, CA; Carter, J Chance [Livermore, CA; Reynolds, John G [San Ramon, CA

    2010-08-10

    An inspection tester system for testing for explosives. The tester includes a body and a swab unit adapted to be removeably connected to the body. At least one reagent holder and dispenser is operatively connected to the body. The reagent holder and dispenser contains an explosives detecting reagent and is positioned to deliver the explosives detecting reagent to the swab unit. A heater is operatively connected to the body and the swab unit is adapted to be operatively connected to the heater.

  3. Explosive Technology Group

    Data.gov (United States)

    Federal Laboratory Consortium — The Explosive Technology Group (ETG) provides diverse technical expertise and an agile, integrated approach to solve complex challenges for all classes of energetic...

  4. Active explosion barrier performance against methane and coal dust explosions

    National Research Council Canada - National Science Library

    J. J. L. du Plessis

    2015-01-01

    Preventing the propagation of methane or coal dust explosions through the use of active explosion-suppression systems remains one of the most underutilised explosion controls in underground coal mines...

  5. Comparison of biotic and abiotic treatment approaches for co-mingled perchlorate, nitrate, and nitramine explosives in groundwater

    Science.gov (United States)

    Schaefer, C. E.; Fuller, M. E.; Condee, C. W.; Lowey, J. M.; Hatzinger, P. B.

    2007-01-01

    Biological and abiotic approaches for treating co-mingled perchlorate, nitrate, and nitramine explosives in groundwater were compared in microcosm and column studies. In microcosms, microscale zero-valent iron (mZVI), nanoscale zero-valent iron (nZVI), and nickel catalyzed the reduction of RDX and HMX from initial concentrations of 9 and 1 mg/L, respectively, to below detection (0.02 mg/L), within 2 h. The mZVI and nZVI also degraded nitrate (3 mg/L) to below 0.4 mg/L, but none of the metal catalysts were observed to appreciably reduce perchlorate (˜ 5 mg/L) in microcosms. Perchlorate losses were observed after approximately 2 months in columns of aquifer solids treated with mZVI, but this decline appears to be the result of biodegradation rather than abiotic reduction. An emulsified vegetable oil substrate was observed to effectively promote the biological reduction of nitrate, RDX and perchlorate in microcosms, and all four target contaminants in the flow-through columns. Nitrate and perchlorate were biodegraded most rapidly, followed by RDX and then HMX, although the rates of biological reduction for the nitramine explosives were appreciably slower than observed for mZVI or nickel. A model was developed to compare contaminant degradation mechanisms and rates between the biotic and abiotic treatments.

  6. Modelling IHE Main Charge Initiation Trains based on HMX and TATB based Booster Charges

    Science.gov (United States)

    Drake, Rodney; Maisey, Matthew

    2015-06-01

    There is always a requirement to reduce the size of initiation trains. However, as the size is reduced the performance characteristics may be compromised. To enable compact and robust initiation trains to be designed requires a detailed science-based understanding of the processes (for example, growth to detonation) which determine the performance characteristics. A numerical modelling study has been performed to understand the designs of initiation trains comprising flyer plate detonator, booster charge and an IHE main charge. The effect of the flyer plate diameter on the distance required to establish uniformly diverging detonation waves in HMX and TATB based booster charges has been studied. Numerical simulations have also examined the effect of the relative sizes of the booster and IHE main charge on the distance required for a stable detonation front to be established in the main charge for both HMX and TATB based booster charges. The implications of the numerical simulations are discussed in terms of the design of initiation trains for IHE main charge systems.

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

    Directory of Open Access Journals (Sweden)

    Lely A. Quina

    2012-11-01

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

  8. Dissociative Electron Attachment to the Nitroamine HMX (Octahydro-1,3,5,7-Tetranitro-1,3,5,7-Tetrazocine)

    National Research Council Canada - National Science Library

    Postler, Johannes; Goulart, Marcelo M; Matias, Carolina; Mauracher, Andreas; da Silva, Filipe Ferreira; Scheier, Paul; Limão-Vieira, Paulo; Denifl, Stephan

    2013-01-01

    In the present study, dissociative electron attachment (DEA) measurements with gas phase HMX, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, C4H8N8O8, have been performed by means of a crossed electron-molecular beam experiment...

  9. Comparison of Pumped and Diffusion Sampling Methods to Monitor Concentrations of Perchlorate and Explosive Compounds in Ground Water, Camp Edwards, Cape Cod, Massachusetts, 2004-05

    Science.gov (United States)

    LeBlanc, Denis R.; Vroblesky, Don A.

    2008-01-01

    Laboratory and field tests were conducted at Camp Edwards on the Massachusetts Military Reservation on Cape Cod to examine the utility of passive diffusion sampling for long-term monitoring of concentrations of perchlorate and explosive compounds in ground water. The diffusion samplers were constructed of 1-inch-diameter rigid, porous polyethylene tubing. The results of laboratory tests in which diffusion samplers were submerged in containers filled with ground water containing perchlorate, RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), and HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) indicate that concentrations inside the diffusion samplers equilibrated with concentrations in the containers within the 19-day-long test period. Field tests of the diffusion samplers were conducted in 15 wells constructed of 2- or 2.5-inch-diameter polyvinyl chloride pipe with 10-foot-long slotted screens. Concentrations of perchlorate, RDX, and HMX in the diffusion samplers placed in the wells for 42 to 52 days were compared to concentrations in samples collected by low-flow pumped sampling from 53 days before to 109 days after retrieval of the diffusion samples. The results of the field tests indicate generally good agreement between the pumped and diffusion samples for concentrations of perchlorate, RDX, and HMX. The concentration differences indicate no systematic bias related to contaminant type or concentration levels.

  10. Imaging Detonations of Explosives

    Science.gov (United States)

    2016-04-01

    14. ABSTRACT The techniques and instrumentation presented in this report allow for mapping of temperature, pressure , chemical species, and...measurement in the explosive near- to far-field (0–500 charge diameters) of surface temperatures, peak air-shock pressures , some chemical species...15. SUBJECT TERMS imaging, explosions, temperature, pressure , chemical species 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU

  11. Explosions and static electricity

    DEFF Research Database (Denmark)

    Jonassen, Niels M

    1995-01-01

    The paper deals with the problem of electrostatic discharges as causes of ignition of vapor/gas and dust/gas mixtures. A series of examples of static-caused explosions will be discussed. The concepts of explosion limits, the incendiveness of various discharge types and safe voltages are explained...

  12. Analysis of explosives using corona discharge ionization combined with ion mobility spectrometry-mass spectrometry.

    Science.gov (United States)

    Lee, Jihyeon; Park, Sehwan; Cho, Soo Gyeong; Goh, Eun Mee; Lee, Sungman; Koh, Sung-Suk; Kim, Jeongkwon

    2014-03-01

    Corona discharge ionization combined with ion mobility spectrometry-mass spectrometry (IMS-MS) was utilized to investigate five common explosives: cyclonite (RDX), trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), cyclotetramethylenetetranitramine (HMX), and 2,4-dinitrotoluene (DNT). The MS scan and the selected ion IMS analyses confirmed the identities of the existing ion species and their drift times. The ions observed were RDX·NO3(-), TNT(-), PETN·NO3(-), HMX·NO3(-), and DNT(-), with average drift times of 6.93 ms, 10.20 ms, 9.15 ms, 12.24 ms, 11.30 ms, and 8.89 ms, respectively. The reduced ion mobility values, determined from a standard curve calculated by linear regression of (normalized drift times)(-1) versus literature K0 values, were 2.09, 1.38, 1.55, 1.15, 1.25, and 1.60 cm(2) V(-1) s(-1), respectively. The detection limits were found to be 0.1 ng for RDX, 10 ng for TNT, 0.5 ng for PETN, 5.0 ng for HMX, and 10 ng for DNT. Simplified chromatograms were observed when nitrogen, as opposed to air, was used as the drift gas, but the detection limits were approximately 10 times worse (i.e., less sensitivity of detection). © 2013 Elsevier B.V. All rights reserved.

  13. Detonation Performance Testing of LX-19

    Science.gov (United States)

    Vincent, Samuel; Aslam, Tariq; Jackson, Scott

    2015-06-01

    CL-20 was developed at the Naval Surface Weapons Center at China Lake, CA in the mid 80's. Being less sensitive than PETN, but considerably more powerful than HMX, it is the highest energy and density compound known among organic chemicals. LX-19 was developed at LLNL in the early 90's. It is a high-energy plastic bonded explosive, composed of 95.8 wt% CL-20 and 4.2 wt% Estane binder, and is similar to LX-14 (composed of HMX and Estane), but with greater sensitivity characteristics with use of the more energetic CL-20 explosive. We report detonation performance results for unconfined cylindrical rate sticks of LX-19. The experimental diameter effects are shown, along with detonation front shapes, and reaction zone profiles for different test diameters. This data is critical for calibration to Detonation Shock Dynamics (DSD). LA-UR-15-20672.

  14. PRESSURE AND TEMPERATURE DEPENDENT DEFLAGRATION RATE MEASUREMENTS OF LLM-105 AND TATB BASED EXPLOSIVES

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-11-10

    The pressure dependent deflagration rates of LLM-105 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. Two different formulations of LLM-105 and three formulations of TATB were studied and 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 TATB formulations causes the deflagration rate to accelerate and become erratic. The thermal and mechanical properties of these formulations will be discussed in the context of their pressure and temperature dependent deflagration rates.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Aging of civil explosives (Poster)

    NARCIS (Netherlands)

    Krabbendam-La Haye, E.L.M.; Klerk, W.P.C. de; Hoen, C. 't; Krämer, R.E.

    2014-01-01

    For the Dutch MoD and police, TNO composed sets with different kinds of civil explosives to train their detection dogs. The manufacturer of these explosives guarantees several years of stability of these explosives. These sets of explosives are used under different conditions, like temperature and

  17. Vibrational and thermal properties of β-HMX and TATB from dispersion corrected density functional theory

    Science.gov (United States)

    Landerville, Aaron C.; Oleynik, Ivan I.

    2017-01-01

    Dispersion Corrected Density Functional Theory (DFT+vdW) calculations are performed to predict vibrational and thermal properties of the bulk energetic materials (EMs) β-octahydrocyclotetramethylene-tetranitramine (β-HMX) and triaminotrinitrobenzene (TATB). DFT+vdW calculations of pressure-dependent crystal structure and the hydrostatic equation of state are followed by frozen-phonon calculations of their respective vibration spectra at each pressure. These are then used under the quasi-harmonic approximation to obtain zero-point and thermal free energy contributions to the pressure, resulting in pressure-volume-temperature (PVT) EOS for each material that are in excellent agreement with experiment. Heat capacities, and coefficients of thermal expansion as functions of temperature are also calculated and compared with experiment.

  18. A theoretical study of the stress relaxation in HMX on the picosecond time scale

    Science.gov (United States)

    Long, Yao; Chen, Jun

    2015-12-01

    The stress relaxation model of β-HMX on the picosecond time scale is studied by a theoretical approach. The relaxation of normal stress is contributed by lattice vibration, and the relaxation of shear stress is contributed by molecular rotation. Based on this model, the energy dissipation rule of the elastic wave and the profile of the shock wave are investigated. We find at low frequency the dissipation rate of the elastic wave is proportional to the power function of frequency, and under high speed shock loading the width of the stress relaxation zone is less than 0.3 μm there is a pressure peak with a height of 14 GPa near the wave front.

  19. Parametric Explosion Spectral Model

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. Explosive Components Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The 98,000 square foot Explosive Components Facility (ECF) is a state-of-the-art facility that provides a full-range of chemical, material, and performance analysis...

  1. Intermittent Explosive Disorder

    Directory of Open Access Journals (Sweden)

    Lut Tamam

    2011-09-01

    Full Text Available Intermittent explosive disorder is an impulse control disorder characterized by the occurrence of discrete episodes of failure to resist aggressive impulses that result in violent assault or destruction of property. Though the prevalence intermittent explosive disorder has been reported to be relatively rare in frontier studies on the field, it is now common opinion that intermittent explosive disorder is far more common than previously thought especially in clinical psychiatry settings. Etiological studies displayed the role of both psychosocial factors like childhood traumas and biological factors like dysfunctional neurotransmitter systems and genetics. In differential diagnosis of the disorder, disorders involving agression as a symptom such as alcohol and drug intoxication, antisocial and borderline personality disorders, personality changes due to general medical conditions and behavioral disorder should be considered. A combination of pharmacological and psychotherapeutic approaches are suggested in the treatment of the disorder. This article briefly reviews the historical background, diagnostic criteria, epidemiology, etiology and treatment of intermittent explosive disorder.

  2. 75 FR 5545 - Explosives

    Science.gov (United States)

    2010-02-03

    ....gov . This Federal Register notice, as well as news releases and other relevant information, are also..., Tobacco, Firearms and Explosives (ATF) regulates the import, manufacture, distribution, and storage of...

  3. Ammonium nitrate explosion hazards

    Directory of Open Access Journals (Sweden)

    Negovanović Milanka

    2015-01-01

    Full Text Available Ammonium nitrate (AN primarily is used as a fertilizer but it is also very important compound in the production of industrial explosives. The application of ammonium nitrate in the production of industrial explosives was related with the early era of Nobel dynamite and widely increased with the appearance of blasting agents such as ANFO and Slurry, in the middle of the last Century. Throughout the world millions of tons of ammonium nitrate are produced annually and handled without incident. Although ammonium nitrate generally is used safely, accidental explosions involving AN have high impact resulting in loss of lives and destruction of property. The paper presents the basic properties of ammonium nitrate as well as hazards in handling of ammonium nitrate in order to prevent accidents. Several accidents with explosions of ammonium nitrate resulted in catastrophic consequences are listed in the paper as examples of non-compliance with prescribed procedures.

  4. Explosion suppression system

    Science.gov (United States)

    Sapko, Michael J.; Cortese, Robert A.

    1992-01-01

    An explosion suppression system and triggering apparatus therefor are provided for quenching gas and dust explosions. An electrically actuated suppression mechanism which dispenses an extinguishing agent into the path ahead of the propagating flame is actuated by a triggering device which is light powered. This triggering device is located upstream of the propagating flame and converts light from the flame to an electrical actuation signal. A pressure arming device electrically connects the triggering device to the suppression device only when the explosion is sensed by a further characteristic thereof beside the flame such as the pioneer pressure wave. The light powered triggering device includes a solar panel which is disposed in the path of the explosion and oriented between horizontally downward and vertical. Testing mechanisms are also preferably provided to test the operation of the solar panel and detonator as well as the pressure arming mechanism.

  5. Shock waves & explosions

    CERN Document Server

    Sachdev, PL

    2004-01-01

    Understanding the causes and effects of explosions is important to experts in a broad range of disciplines, including the military, industrial and environmental research, aeronautic engineering, and applied mathematics. Offering an introductory review of historic research, Shock Waves and Explosions brings analytic and computational methods to a wide audience in a clear and thorough way. Beginning with an overview of the research on combustion and gas dynamics in the 1970s and 1980s, the author brings you up to date by covering modeling techniques and asymptotic and perturbative methods and ending with a chapter on computational methods.Most of the book deals with the mathematical analysis of explosions, but computational results are also included wherever they are available. Historical perspectives are provided on the advent of nonlinear science, as well as on the mathematical study of the blast wave phenomenon, both when visualized as a point explosion and when simulated as the expansion of a high-pressure ...

  6. Explosive Welding with Nitroguanidine.

    Science.gov (United States)

    Sadwin, L D

    1964-03-13

    By using the explosive nitroguanidine, continuous welds can be made between similar and dissimilar metals. Since low detonation pressures are attainable, pressure transfer media are not required between the explosive and the metal surface. The need for either a space or an angle between the metals is eliminated, and very low atmospheric pressures are not required. Successful welds have been made between tantalum and 4140 steel, 3003H14 aluminum and 4140 steel, and 304 stainless steel and 3003H14 aluminum.

  7. Overview of Explosive Initiators

    Science.gov (United States)

    2015-11-01

    important characteristics of an effective primary explosive is an extremely swift deflagration to detonation transition, meaning that once the... Taylor , G. W. C., Napier, S. E., "Preparation of Explosive Substances Containing Carboxymethyl Cellulose," U.S. Patent 3,291,664, 1966. 8 Perich, A...Rinkenbach, W. H., "Study of the Action of Lead Azide on Copper," U.S. Army ARDEC, Picatinny Arsenal, NJ, Technical Report No. 1152, 1942. 11 Taylor , G. W

  8. Handbook of HE (High Explosives) Explosive Effects

    Science.gov (United States)

    1986-04-11

    uPcup SI.B iPip P 3 [ xpI os i or ,tf fects, Lx’i Osions In Air,6 19 6T~lT’ Explosions, Airblast - 19 ABSTRAC.T ’Continuje on "uri~ee it neczessary and...AIR FORCE INSTITUTE OF TECHNOLOGY/EN ATTN: MAT 0323 ATTN- LIURARY/AFIT/LDEE NAVAL OCEAN SYSTEMS CENTER AIR FORCE LOGISTICS COMMAND ATTN: CODE 825

  9. 49 CFR 172.522 - EXPLOSIVES 1.1, EXPLOSIVES 1.2 and EXPLOSIVES 1.3 placards.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false EXPLOSIVES 1.1, EXPLOSIVES 1.2 and EXPLOSIVES 1.3... INFORMATION, TRAINING REQUIREMENTS, AND SECURITY PLANS Placarding § 172.522 EXPLOSIVES 1.1, EXPLOSIVES 1.2 and EXPLOSIVES 1.3 placards. (a) Except for size and color, the EXPLOSIVES 1.1, EXPLOSIVES 1.2 and EXPLOSIVES 1.3...

  10. Compaction shock dissipation in low density granular explosive

    Science.gov (United States)

    Rao, Pratap T.; Gonthier, Keith A.; Chakravarthy, Sunada

    2016-06-01

    The microstructure of granular explosives can affect dissipative heating within compaction shocks that can trigger combustion and initiate detonation. Because initiation occurs over distances that are much larger than the mean particle size, homogenized (macroscale) theories are often used to describe local thermodynamic states within and behind shocks that are regarded as the average manifestation of thermodynamic fields at the particle scale. In this paper, mesoscale modeling and simulation are used to examine how the initial packing density of granular HMX (C4H8N8O8) C4H8N8O8 having a narrow particle size distribution influences dissipation within resolved, planar compaction shocks. The model tracks the evolution of thermomechanical fields within large ensembles of particles due to pore collapse. Effective shock profiles, obtained by averaging mesoscale fields over space and time, are compared with those given by an independent macroscale compaction theory that predicts the variation in effective thermomechanical fields within shocks due to an imbalance between the solid pressure and a configurational stress. Reducing packing density is shown to reduce the dissipation rate within shocks but increase the integrated dissipated work over shock rise times, which is indicative of enhanced sensitivity. In all cases, dissipated work is related to shock pressure by a density-dependent power law, and shock rise time is related to pressure by a power law having an exponent of negative one.

  11. Compaction shock dissipation in low density granular explosive

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Pratap T.; Gonthier, Keith A., E-mail: gonthier@me.lsu.edu; Chakravarthy, Sunada [Mechanical and Industrial Engineering Department, Louisiana State University, Baton Rouge, Louisiana 70803 (United States)

    2016-06-14

    The microstructure of granular explosives can affect dissipative heating within compaction shocks that can trigger combustion and initiate detonation. Because initiation occurs over distances that are much larger than the mean particle size, homogenized (macroscale) theories are often used to describe local thermodynamic states within and behind shocks that are regarded as the average manifestation of thermodynamic fields at the particle scale. In this paper, mesoscale modeling and simulation are used to examine how the initial packing density of granular HMX (C{sub 4}H{sub 8}N{sub 8}O{sub 8}) C{sub 4}H{sub 8}N{sub 8}O{sub 8} having a narrow particle size distribution influences dissipation within resolved, planar compaction shocks. The model tracks the evolution of thermomechanical fields within large ensembles of particles due to pore collapse. Effective shock profiles, obtained by averaging mesoscale fields over space and time, are compared with those given by an independent macroscale compaction theory that predicts the variation in effective thermomechanical fields within shocks due to an imbalance between the solid pressure and a configurational stress. Reducing packing density is shown to reduce the dissipation rate within shocks but increase the integrated dissipated work over shock rise times, which is indicative of enhanced sensitivity. In all cases, dissipated work is related to shock pressure by a density-dependent power law, and shock rise time is related to pressure by a power law having an exponent of negative one.

  12. Partitioning model of the adsorption of explosives from soils to determine its environmental fate

    Directory of Open Access Journals (Sweden)

    Rosalina González Forero

    2014-12-01

    Full Text Available The purpose of this research was to identify the principal soil characteristics that influence the adsorption of munitions constituents (MC of explosives in soils, through a partitioning model to determine the fate of the explosives. To do that, batch experiments near 1:1 (w/v soil to solution ratios reflecting field conditions were conducted using a mixture of HMX, RDX, nitroglycerine (NG, nitroguanidine (NQ, TNT and 2,4-dinitrotoluene as MC, where the mix of MC was adsorbed in twenty-five different soils that varied from 4.0 to 43.2 % clay content and 0.07 to 18.23 % total carbon, in an experiment that involved 2 days of adsorption followed by four consecutive desorption steps. The most important result was that for each MC, even if it was in a mixture, were successfully predicted the partition coefficients using the organic carbon, cation exchange capacity and extractable iron as the principal soil characteristics that determine the fate of these explosives.

  13. HMX: Analysis of Dosing Formulations Used in Acute, Sub-Acute and Sub-Chronic Toxicity Studies.

    Science.gov (United States)

    1985-07-31

    finding studies were prepared in 0.5% low viscosity carboxymethylcellulose (CMC). Aliquots for analysis were removed at intervals during the dosing of each...diets prepared for toxicity studies by reverse phase HPLC. Dietary preparations were stable for at least 21 days when stored in ambient conditions in...the dark. Almost all the dosing solutions and diets prepared for a range of studies were shown to contain dose to the desired concentrations of HMX

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  15. Explosive welding of pipes

    Energy Technology Data Exchange (ETDEWEB)

    Drennov, O.; Burtseva, O.; Kitin, A. [Russian Federal Nuclear Center, Sarov (Russian Federation)

    2006-08-15

    Arrangement of pipelines for the transportation of oil and gas is a complicated problem. In this paper it is suggested to use the explosive welding method to weld pipes together. This method is rather new. This method can be advantageous (saving material and physical resources) comparing to its static analogs (electron-beam welding, argon-arc welding, plasma welding, gas welding, etc.), in particular, in hard-to-reach areas due to their geographic and climatic conditions. We suggest to perform explosive welding according to the following scheme: the ends of the 2 pipes are connected, the external surfaces are kept at a similar level. A cylindrical steel layer of diameter larger than the pipe diameter is set around the pipe joint and an explosive charge is placed on its external surface. The basic problem is the elimination of strains and reduction of pipe diameter in the area of the dynamic effect. The suggestion is to use water as filler: the volume of pipes in the area adjacent to the zone of explosive welding is totally filled with water. The principle of non-compressibility of liquid under quasi-dynamic loading is used. In one-dimensional gas dynamic and elastic-plastic calculations we determined non-deformed mass of water. Model experiments with pipes having radii R = 57 mm confirmed results of the calculations and the possibility in principle to weld pipes by explosion with use of water as filler.

  16. Surface explosion cavities

    CERN Document Server

    Benusiglio, Adrien; Clanet, Christophe

    2012-01-01

    We present a fluid dynamics video on cavities created by explosions of firecrackers at the water free surface. We use three types of firecrackers containing 1, 1.3 and 5 g of flash powder. The firecrackers are held with their center at the surface of water in a cubic meter pool. The movies are recorded from the side with a high-speed video camera. Without confinement the explosion produces an hemispherical cavity. Right after the explosion this cavity grows isotropically, the bottom then stops while the sides continue to expand. In the next phase the bottom of the cavity accelerates backwards to the surface. During this phase the convergence of the flow creates a central jet that rises above the free surface. In the last part of the video the explosion is confined in a vertical open tube made of glass and of centimetric diameter. The explosion creates a cylindrical cavity that develops towards the free end of the tube. Depending on the charge, the cavity can either stop inside the tube or at its exit, but nev...

  17. Explosion containment device

    Science.gov (United States)

    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.

  18. An excimer-based FAIMS detector for detection of ultra-low concentration of explosives

    Science.gov (United States)

    Chistyakov, Alexander A.; Kotkovskii, Gennadii E.; Sychev, Alexey V.; Perederiy, Anatoly N.; Budovich, V. L.; Budovich, D. V.

    2014-05-01

    A new method of explosives detection based on the field asymmetric ion mobility spectrometry (FAIMS) and ionization by an excimer emitter has been developed jointly with a portable detector. The excimer emitter differs from usual UVionizing lamps by mechanism of emitting, energy and spectral characteristics. The developed and applied Ar2-excimer emitter has the working volume of 1 cm3, consuming power 0.6 W, the energy of photons of about 10 eV (λ=126 nm), the FWHM radiation spectrum of 10 nm and emits more than 1016 photon per second that is two orders of magnitude higher than UV-lamp of the same working volume emits. This also exceeds by an order of magnitude the quantity of photons per second for 10-Hz solid state YAG:Nd3+ - laser of 1mJ pulse energy at λ=266 nm that is also used to ionize the analyte. The Ar2-excimer ionizes explosives by direct ionization mechanism and through ionization of organic impurities. The developed Ar2-excimer-based ion source does not require cooling due to low level discharge current of emitter and is able to work with no repair more than 10000 hrs. The developed excimer-based explosives detector can analyze both vapors and traces of explosives. The FAIMS spectra of the basic types of explosives like trinitrotoluene (TNT), cyclotrimethylenetrinitramine (RDX), dinitrotoluene (DNT), cyclotetramethylenetetranitramine (HMX), nitroglycerine (NG), pentaerythritol tetranitrate (PETN) under Ar2-excimer ionization are presented. The detection limit determined for TNT vapors equals 1x10-14 g/cm3, for TNT traces- 100 pg.

  19. Novel high explosive compositions

    Science.gov (United States)

    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)

  20. A real explosion: the requirement of steam explosion pretreatment.

    Science.gov (United States)

    Yu, Zhengdao; Zhang, Bailiang; Yu, Fuqiang; Xu, Guizhuan; Song, Andong

    2012-10-01

    The severity factor is a common term used in steam explosion (SE) pretreatment that describes the combined effects of the temperature and duration of the pretreatment. However, it ignores the duration of the explosion process. This paper describes a new parameter, the explosion power density (EPD), which is independent of the severity factor. Furthermore, we present the adoption of a 5m(3) SE model for a catapult explosion mode, which completes the explosion within 0.0875 s. The explosion duration ratio of this model to a conventional model of the same volume is 1:123. The comparison between the two modes revealed a qualitative change by explosion speed, demonstrating that this real explosion satisfied the two requirements of consistency, and suggested a guiding mechanism for the design of SE devices.

  1. Measurements and ALE3D Simulations for Violence in a Scaled Thermal Explosion Experiment with LX-10 and AerMet 100 Steel

    Energy Technology Data Exchange (ETDEWEB)

    McClelland, M A; Maienschein, J L; Yoh, J J; deHaven, M R; Strand, O T

    2005-06-03

    We completed a Scaled Thermal Explosion Experiment (STEX) and performed ALE3D simulations for the HMX-based explosive, LX-10, confined in an AerMet 100 (iron-cobalt-nickel alloy) vessel. The explosive was heated at 1 C/h until cookoff at 182 C using a controlled temperature profile. During the explosion, the expansion of the tube and fragment velocities were measured with strain gauges, Photonic-Doppler-Velocimeters (PDVs), and micropower radar units. These results were combined to produce a single curve describing 15 cm of tube wall motion. A majority of the metal fragments were captured and cataloged. A fragment size distribution was constructed, and a typical fragment had a length scale of 2 cm. Based on these results, the explosion was considered to be a violent deflagration. ALE3D models for chemical, thermal, and mechanical behavior were developed for the heating and explosive processes. A four-step chemical kinetics model is employed for the HMX while a one-step model is used for the Viton. A pressure-dependent deflagration model is employed during the expansion. The mechanical behavior of the solid constituents is represented by a Steinberg-Guinan model while polynomial and gamma-law expressions are used for the equation of state of the solid and gas species, respectively. A gamma-law model is employed for the air in gaps, and a mixed material model is used for the interface between air and explosive. A Johnson-Cook model with an empirical rule for failure strain is used to describe fracture behavior. Parameters for the kinetics model were specified using measurements of the One-Dimensional-Time-to-Explosion (ODTX), while measurements for burn rate were employed to determine parameters in the burn front model. The ALE3D models provide good predictions for the thermal behavior and time to explosion, but the predicted wall expansion curve is higher than the measured curve. Possible contributions to this discrepancy include inaccuracies in the chemical models

  2. Coupled reversed-phase and ion chromatographic system for the simultaneous identification of inorganic and organic explosives.

    Science.gov (United States)

    Tyrrell, Eadaoin; Dicinoski, Greg W; Hilder, Emily F; Shellie, Robert A; Breadmore, Michael C; Pohl, Christopher A; Haddad, Paul R

    2011-05-20

    There are many methods available to detect and positively identify either organic or inorganic explosives separately, however no one method has been developed which can detect both types of explosive species simultaneously from a single sample. In this work, a unique coupled-chromatographic system is reported for the simultaneous determination of both organic and inorganic explosive species and is used for pre-blast analysis/identification purposes. This novel approach is based on the combination of reversed-phase high performance liquid chromatography and ion chromatography which allows trace levels of organic and inorganic explosives to be determined simultaneously from a single sample. Using this procedure, a 20 min reversed-phase separation of organic explosives is coupled to a 16 min ion-exchange separation of anions present in inorganic explosives, providing a complete pre-blast analysis/identification system for the separation and detection of a complex mixture containing organic and/or inorganic explosive species. The total analysis time, including sufficient column re-equilibration between runs, was <25 min using the coupled system. By this method, the minimum resolution for the organic separation was 1.16 between nitroglycerin and tetryl and the detection limits ranged from 0.31 mg L(-1) for cyclotetramethylene tetranitramine (HMX) and 1.54 mg L(-1) for pentaerythrite tetranitrate (PETN), while the minimum resolution for the inorganic separation was 0.99 between azide and nitrate, and the detection limits ranged from 7.70 μg L(-1) for fluoride and 159.50 μg L(-1) for benzoate. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  3. High-nitrogen explosives

    Energy Technology Data Exchange (ETDEWEB)

    Naud, D. (Darren); Hiskey, M. A. (Michael A.); Kramer, J. F. (John F.); Bishop, R. L. (Robert L.); Harry, H. H. (Herbert H.); Son, S. F. (Steven F.); Sullivan, G. K. (Gregg 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 DAAz

  4. Rapid, on-site identification of explosives in nanoliter droplets using a UV reflected fiber optic sensor.

    Science.gov (United States)

    Li, Xin; Li, Qiang; Zhou, Hong; Hao, Hongxia; Wang, Tongzhou; Zhao, Songmin; Lu, Ying; Huang, Guoliang

    2012-11-02

    A portable UV (190-400 nm) spectrophotometric based reflected fiber optic sensor system is presented for the on-site detection and identification of explosives. A reflected fiber optic sensor for explosives analysis was developed, with low sample consumption (20-100 nL) and a wide concentration quantification range (1.1-250 mg L(-1)). Seven common explosives [pentaerythritol tetranitrate (PETN), trinitrophenylmethylnitramine (CE), trinitrotoluene (TNT), dinitrotoluene (DNT), picric acid (PA), cyclotetramethylenetetranitramine (HMX), cyclotrimethylenetrinitramine (RDX)] and a PETN-RDX mixture (to simulate the Semtex used in many terrorist bombings) were quantitatively analyzed and identified by the proposed system in less than 3s per test, with limits of detection (LOD) of 0.3 mg L(-1). Due to chemical interference problems in the UV wavelengths range, a novel feature matching algorithm (FMA) was proposed for explosive identification, which was proved to have higher specificity and better anti-interference ability. Real post-blast debris samples were analyzed by the proposed method, and the results were validated against an LC/MS/MS method. The rapid, cost-effective detection with low sample consumption and wide applicability achieved by this system is highly suitable for homeland security on-site applications, such as rapid sample screening in post-blast debris. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Application of explosive welding to heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, G.

    1983-10-01

    The subject is discussed under the headings: advantages of explosive welding; principle of explosive welding; explosive welding of tubes; metallurgy of explosive welds (micrographs; microhardness); tubular heat exchangers; plugging; sleeving; retubing; construction of new heat exchangers; thermal sleeves.

  6. Violent Reactions and DDT in Hot, Thermally Damaged HMX-Based PBXs

    Energy Technology Data Exchange (ETDEWEB)

    Parker, Gary R. Jr. [Los Alamos National Laboratory; Holmes, Matthew D. [Los Alamos National Laboratory; Dickson, Peter [Los Alamos National Laboratory; Asay, Blaine W. [Los Alamos National Laboratory; McAfee, John M. [Los Alamos National Laboratory

    2012-07-03

    Conventional high explosives (e.g. PBX 9501, LX-07) have been observed to react violently following thermal insult: (1) Fast convective and compressive burns (HEVR); (2) Thermal explosions (HEVR); and (3) Deflagration-to-detonation transition (DDT). No models exist that sufficiently capture/predict these complex multiphase and multiscale behaviors. For now, research is focused on identifying vulnerabilities and factors that control this behavior.

  7. The Information Explosion.

    Science.gov (United States)

    Kuhns, William

    Three facets of the media--events, myths, and sales pitches--constitute the most important lines of force taken by the information bombardment which all of us encounter and are influenced by every day. The focus of this book is on the changes created and hastened by this information explosion of the media bombardment: how we can live with them,…

  8. Conventional Weapons Underwater Explosions

    Science.gov (United States)

    1988-12-01

    te that the heat of detonation (the energy available per mass of explosive) is an increasing function of the aluminum content. As shown in Table 2...the heat of detonation of RDX is 6.15 MJ/kg; addition of 30 wt % Al increases this to 10.12 - a factor of 1.64. Fig. 12 indicates a bubble energy

  9. Explosives Safety Competency Study

    Science.gov (United States)

    2010-07-13

    Munitions Systems Journeyman CDC—AFSC 2W051 Combat Ammunition Planning and Production—AFCOMAC Munitions Systems Craftsman Course—AFSC 2W071 Combat...Ammunition Planning and Production—AFCOMAC Munitions Systems Craftsman Course—AFSC 2W071 Navy Basics of Naval Explosives Hazard Control—AMMO-18 b

  10. Explosions during galaxy formation

    Directory of Open Access Journals (Sweden)

    Hugo Martel

    2001-01-01

    Full Text Available As an idealized model of the e ects of energy release by supernovae during galaxy formation, we consider an explosion at the center of a halo which forms at the intersection of laments in the plane of a cosmological pancake by gravitational instability during pancake collapse. Such halos resemble the virialized objects found in N{body simulations in a CDM universe and, therefore, serve as a convenient, scale{free test{bed model for galaxy formation. ASPH=P3M simulations reveal that such explosions are anisotropic. The energy and metals are channeled into the low density regions, away from the pancake plane. The pancake remains essentially undisturbed, even if the explosion is strong enough to blow away all the gas lo- cated inside the halo at the onset of the explosion and reheat the IGM surrounding the pancake. Infall quickly replenishes this ejected gas and gradually restores the gas fraction as the halo mass continues to grow. Estimates of the collapse epoch and SN energy{release for galaxies of di erent mass in the CDM model can re- late these results to scale{dependent questions of blow{out and blow{away and their implication for early IGM heating and metal enrichment and the creation of dark{matter{dominated dwarf galaxies.

  11. Portable raman explosives detection

    Energy Technology Data Exchange (ETDEWEB)

    Moore, David Steven [Los Alamos National Laboratory; Scharff, Robert J [Los Alamos National Laboratory

    2008-01-01

    Recent advances in portable Raman instruments have dramatically increased their application to emergency response and forensics, as well as homeland defense. This paper reviews the relevant attributes and disadvantages of portable Raman spectroscopy, both essentially and instrumentally, to the task of explosives detection in the field.

  12. New explosive seam welding concepts

    Science.gov (United States)

    Bement, L. J.

    1973-01-01

    Recently developed techniques provide totally-confined linear explosive seam welding and produce scarf joint with linear explosive seam welding. Linear ribbon explosives are utilized in making narrow, continuous, airtight joints in variety of aluminum alloys, titanium, copper, brass, and stainless steel.

  13. Threshold Studies of Heated HMX-Based Energetic Material Targets Using the Steven Impact Test

    Energy Technology Data Exchange (ETDEWEB)

    Switzer, L L; Vandersall, K S; Chidester, S K; Greenwood, D W; Tarver, C M

    2003-07-01

    Impact tests performed at low velocity on heated energetic material samples are of interest when considering the situation of energetic materials involved in a fire. To determine heated reaction thresholds, Steven Test targets containing PBX 9404 or LX-04 samples heated to the range of 150-170 C were impacted at velocities up to 150 m/s by two different projectile head geometries. Comparing these measured thresholds to ambient temperature thresholds revealed that the heated LX-04 thresholds were considerably higher than ambient, whereas the heated PBX 9404 thresholds were only slightly higher than the ambient temperature thresholds. The violence of reaction level of the PBX 9404 was considerably higher than that of the LX-04 as measured with four overpressure gauges. The varying results in these samples with different HMX/binder configurations indicate that friction plays a dominant role in reaction ignition during impact. This work outlines the experimental details, compares the thresholds and violence levels of the heated and ambient temperature experiments, and discusses the dominant mechanisms of the measured thresholds.

  14. Effect of Nitrate Ester on the Combustion Characteristics of PET/HMX -based Propellants

    Directory of Open Access Journals (Sweden)

    Yunlan Sun

    2011-04-01

    Full Text Available The effect of nitrate ester NG/TEGDN on the combustion characteristics of PET/HMX-based propellants has been experimentally investigated using of high-speed photography technique and scanning electron microscopy. It is indicated that the increase of NG/TEGDN content has little impact on the propellant burning rates at the same pressure. Furthermore, propellant can not be self-sustaining combustion at low pressure (£1 MPa. The increase of NG/TEGDN content does not affect the flame structure of propellant, but it plays an important role in condensed phase reaction zone. The flame structure of propellant is estimated. The thermal decomposition products in different combustion zones are also discussed. Scanning electron microscopy examination of quenched sample indicates that a liquified layer forms during combustion of these propellants. Numerous gas bubbles are present. Especially, the burning surface of propellant with low NG/TEGDN content shows signs of crystallization. The thickness of condensed phase reaction zone, by cross-section examination of propellant burning surface, has also been investigated. The results show that the thickness of condensed phase reaction zone increases with NG/TEGDN content increasing. These observations suggest that the condensed phase zone plays significant role in propellant combustion.Defence Science Journal, 2011, 61(3, pp.206-213, DOI:http://dx.doi.org/10.14429/dsj.61.567

  15. Sensitivity of 2,6-Diamino-3, 5-Dinitropyrazine-1-Oxide

    Energy Technology Data Exchange (ETDEWEB)

    Tarver, C M; Urtiew, P A; Tran, T D

    2005-01-20

    The thermal and shock sensitivities of plastic bonded explosive formations based on 2,6-diamino-3,5-dinitropyrazine-1-oxide (commonly called LLM-105 for Lawrence Livermore Molecule No.105) are reported. The One Dimensional Time to Explosion (ODTX) apparatus was used to generate times to thermal explosion at various initial temperatures. A four-reaction chemical decomposition model was developed to calculate the time to thermal explosion versus inverse temperature curve. Three embedded manganin pressure gauge experiments were fired at different initial pressures to measure the pressure buildup and the distance required for transition to detonation. An Ignition and Growth reactive model was calibrated to this shock initiation data. LLM-105 exhibited thermal and shock sensitivities intermediate between those of triaminotrinitrobenzene (TATB) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazine (HMX).

  16. Modeling the material strength and equations of state of beta-HMX from both first-principles calculations and molecular dynamics simulations

    Science.gov (United States)

    Peng, Qing; Wang, Guangyu; Liu, G. R.; de, Suvranu

    2015-06-01

    We investigate the elastic constants and equations of state (EOS) of the β-polymorph of cyclotetramethylene tetranitramine (HMX) energetic molecular crystal using density functional theory (DFT) calculations. The combination of vdW-DF2 van der Waals functionals and PBE exchange-correlation functionals gives optimized results. The DFT results are used to optimize the Reactive Force Field (ReaxFF). The material strength and EOS of beta-HMX at finite temperatures are then predicted from ReaxFF molecular dynamics simulations. Our results suggest that the optimized ReaxFF predicts the mechanics and EOS of beta-HMX well. The authors would like to acknowledge the generous financial support from the Defense Threat Reduction Agency (DTRA) Grant # HDTRA1-13-1-0025.

  17. Development of ammonium nitrate based explosives to optimize explosive properties and explosive welding parameters used during explosion cladding

    Science.gov (United States)

    Hurley, Christoph

    The ability to accurately measure and predict the velocity of explosively driven flyer plates has been a subject of significant work by the explosives community for some time. The majority of this work has focused on the use of high-energy, ideal explosives that are of interest for defense applications. Several attempts have been made to modify the experimental methods developed for these ideal explosives for use in testing low-energy, non-ideal explosive compounds (including industrially useful mixtures of ammonium nitrate, fuels, and additives) with varying degrees of success. The detonation properties of non-ideal explosives are difficult to measure precisely due to the effect of physical, environmental, and geometric factors on the detonation of these materials. The work presented in this document attempts to mitigate the variability inherent in measurements of non-ideal, ammonium nitrate-based explosives by performing testing using charge geometry similar to that used in the industrial process of explosion welding. A method to measure flyer plate velocity with optical high-speed imaging using commercially available equipment is described. Flyer plate velocity data from both experimental measurements and numerical modeling is presented. A new formula for predicting explosive energy based on the detonation velocity of an ammonium nitrate based explosive in a planar geometry is proposed and applied to a theoretical explosive cladding scenario.

  18. Characteristic Research on Evaporated Explosive Film

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The evaporation source of evaporated explosive was designed and improved based on the inherent specialties of explosive. The compatibility of explosives and addition agent with evaporation vessels was analyzed. The influence of substrate temperature on explosive was analyzed, the control method of substrate temperature was suggested. The influences of evaporation rate on formation of explosive film and mixed explosive film were confirmed. Optimum evaporation rate for evaporation explosive and the better method for evaporating mixed explosive were presented. The necessary characteristics of the evaporated explosive film were obtained by the research of the differences between the evaporated explosive and other materials.

  19. Explosive bulk charge

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Jacob Lee

    2015-04-21

    An explosive bulk charge, including: a first contact surface configured to be selectively disposed substantially adjacent to a structure or material; a second end surface configured to selectively receive a detonator; and a curvilinear side surface joining the first contact surface and the second end surface. The first contact surface, the second end surface, and the curvilinear side surface form a bi-truncated hemispherical structure. The first contact surface, the second end surface, and the curvilinear side surface are formed from an explosive material. Optionally, the first contact surface and the second end surface each have a substantially circular shape. Optionally, the first contact surface and the second end surface consist of planar structures that are aligned substantially parallel or slightly tilted with respect to one another. The curvilinear side surface has one of a smooth curved geometry, an elliptical geometry, and a parabolic geometry.

  20. Explosive welding underwater

    Energy Technology Data Exchange (ETDEWEB)

    Sim, T.; Allen, K.; Lowes, J.M.

    1980-06-11

    Explosive welding underwater is described. First and second underwater tubular members are assembled together so that the outer surface of the first tubular member and the inner surface of the second tubular member are spaced apart to form an annular cavity. The cavity is closed by seals accommodated in portions of the second tubular member, and is then cleaned and dried and filled with a gas at a pressure greater than the surrounding water pressure. The pressure in the cavity is reduced prior to detonating an explosive charge within the first tubular member to weld the members together. The second tubular member may include portions for receiving further seals so as to subdivide the cavity into a number of zones. The pressures in the zones then can be separately adjusted so as to be able to control the pressure difference a cross each seal. 9 claims.

  1. Explosion of Leidenfrost Droplets

    Science.gov (United States)

    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).

  2. Explosive Turbulent Magnetic Reconnection

    OpenAIRE

    Higashimori, Katsuaki; Yokoi, Nobumitsu; Hoshino, Masahiro

    2013-01-01

    We report simulation results for turbulent magnetic reconnection obtained using a newly developed Reynolds-averaged magnetohydrodynamics model. We find that the initial Harris current sheet develops in three ways, depending on the strength of turbulence: laminar reconnection, turbulent reconnection, and turbulent diffusion. The turbulent reconnection explosively converts the magnetic field energy into both kinetic and thermal energy of plasmas, and generates open fast reconnection jets. This ...

  3. Explosive Welding of Pipes

    Science.gov (United States)

    Drennov, Oleg; Drennov, Andrey; Burtseva, Olga

    2013-06-01

    For connection by welding it is suggested to use the explosive welding method. This method is rather new. Nevertheless, it has become commonly used among the technological developments. This method can be advantageous (saving material and physical resources) comparing to its statical analogs (electron-beam welding, argon-arc welding, plasma welding, gas welding, etc.), in particular, in hard-to-reach areas due to their geographic and climatic conditions. Explosive welding of cylindrical surfaces is performed by launching of welded layer along longitudinal axis of construction. During this procedure, it is required to provide reliable resistance against radial convergent strains. The traditional method is application of fillers of pipe cavity, which are dense cylindrical objects having special designs. However, when connecting pipes consecutively in pipelines by explosive welding, removal of the fillers becomes difficult and sometimes impossible. The suggestion is to use water as filler. The principle of non-compressibility of liquid under quasi-dynamic loading is used. In one-dimensional gasdynamic and elastic-plastic calculations we determined non-deformed mass of water (perturbations, which are moving in the axial direction with sound velocity, should not reach the layer end boundaries for 5-7 circulations of shock waves in the radial direction). Linear dimension of the water layer from the zone of pipe coupling along axis in each direction is >= 2R, where R is the internal radius of pipe.

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

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph Ds [Los Alamos National Laboratory

    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.

  5. PNMA在HMX/Al-CMDB推进剂中的应用%Application of PNMA in HMX/Al-CMDB Propellant

    Institute of Scientific and Technical Information of China (English)

    刘所恩; 陈锦芳; 潘葆; 赵美玲; 宫慧心; 张国辉; 任晓斌

    2014-01-01

    A modified double-base propellant containing HMX and Al powder (HMX/Al-CMDB)with P-Nitro-N-methylamine (PNMA)as energetic chemical stabilizer was prepared by traditional solventless method and screw extrusion process.The effects of PNMA on the preparation process,chemical stability,mechanical performance and energy characteristics of HMX/Al-CMDB propellant were studied.The results show that the time needed for color change in methyl-violet test is substantially increased when N,N′-dimethyl-N,N′-diphenylurea (C2 )is partially or totally replaced by PNMA,indicating that the stability of the HMX/Al-CMDB propellant containing PNMA is significantly improved.The time needed for color change of test paper increases with the increase of the proportion of PNMA in the formulation.After the substitution of C2 by PNMA,the density of the propellant has no change, the heat of detonation increases by 52 kJ/kg and the energy increases remarkably,which is beneficial to reduce pressure exponent and has no adverse effect on the mechanical property and manufacturing process of the propellant.%采用传统的无溶剂法和螺压工艺制备了以 N-甲基对硝基苯胺(PNMA)为含能化学安定剂的 HMX/Al-CMDB推进剂,研究了PNMA 对推进剂的制备工艺、化学安定性、力学性能及能量特性的影响。结果表明,用PMNA部分或完全替代Ⅱ号中定剂(C2)后,甲基紫化学安定性试验试纸变色时间大幅度增长,表明含 PNMA 的HMX/Al-CMDB推进剂的化学安定性显著提高,随着PNMA含量的增加,试纸变色所需时间增加。用PNMA 替代C2后,推进剂的密度没有变化,爆热值增加52 kJ/kg,能量有较大提高,对降低压强指数有利,但对推进剂力学性能以及制造工艺无不良影响。

  6. Some nitrogen-rich heterocycles derivatives as potential explosives and propellants: A theoretical study

    Directory of Open Access Journals (Sweden)

    Frem Dany

    2016-01-01

    Full Text Available Four types of nitrogen-rich heterocycles substituted with -NO2, -NHNO2 and -C(NO23 explosophoric groups were explored as potential explosives and propellants materials. The calculated crystal density (ρ0and the condensed phase heat of formation (ΔH·0ffor each of the twelve structures investigated shows that all these derivatives possess high (1.834-1.980 g cm-3(ΔH·0f and (605-2130 kJ kg-1 values. Interesting properties such as detonation velocity (D, pressure (P and specific impulse (Isp were calculated using the Kamlet-Jacobs method and ISPBKW thermochemical code. Detonation velocity and pressure in excess of 8.44 km s-1 and 32.87 GPa was obtained in all cases. Furthermore, trinitromethyl substituted derivatives shows performance exceeding that of HMX with an estimated D = 9.32-9.72 km s-1 and P = 40.61-43.82 GPa. Some -NO2 and -NHNO2 substituted derivatives were shown to be impact insensitive while retaining good detonation performance and thus are regarded as potential replacement for current RDX -based explosives. Finally, the calculated specific impulse (Isp between 248 and 270 s of all investigated derivatives indicate that these energetic materials can be considered as possible ingredient in future rocket propellant compositions.

  7. An examination of blast and impulse effects from the metal loading of explosives

    Energy Technology Data Exchange (ETDEWEB)

    Sanders, Victor E [Los Alamos National Laboratory; Zucker, Jonathan M [Los Alamos National Laboratory; Mc Afee, John M [Los Alamos National Laboratory; Tappan, Bryce C [Los Alamos National Laboratory; Asay, Blaine W [Los Alamos National Laboratory

    2010-01-01

    Explosive compositions loaded with various metal particulates were produced and tested using a unique experimental configuration. The high explosive HMX was used as the standard and was tested over a range of mass loading fractions using tungsten and tantalum as metal additives. The diagnostics used in this set of experiments included free-field blast sensors, dynamic force sensors, time-of-arrival sensors, and a high-speed digital camera. The experimental arrangement allowed for concurrent spatial measurements of the static pressure from expanding gaseous detonation products, along with the total force from the combination of gaseous products and solid particles. The total pressure from the multi-phase products was calculated by measuring the total force applied to the surface of a newly developed force sensor. The results from the force sensor and other measurement techniques were validated against existing numerical methods. The relationship between static and dynamic pressures as a function of metal loading fraction was examined empirically at several distances from the charge for two distinct metal additives.

  8. Nanosensors for trace explosive detection

    OpenAIRE

    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, co...

  9. Broad spectrum infrared thermal desorption of wipe-based explosive and narcotic samples for trace mass spectrometric detection.

    Science.gov (United States)

    Forbes, Thomas P; Staymates, Matthew; Sisco, Edward

    2017-08-07

    Wipe collected analytes were thermally desorbed using broad spectrum near infrared heating for mass spectrometric detection. Employing a twin tube filament-based infrared emitter, rapid and efficiently powered thermal desorption and detection of nanogram levels of explosives and narcotics was demonstrated. The infrared thermal desorption (IRTD) platform developed here used multi-mode heating (direct radiation and secondary conduction from substrate and subsequent convection from air) and a temperature ramp to efficiently desorb analytes with vapor pressures across eight orders of magnitude. The wipe substrate experienced heating rates up to (85 ± 2) °C s(-1) with a time constant of (3.9 ± 0.2) s for 100% power emission. The detection of trace analytes was also demonstrated from complex mixtures, including plastic-bonded explosives and exogenous narcotics, explosives, and metabolites from collected artificial latent fingerprints. Manipulation of the emission power and duration directly controlled the heating rate and maximum temperature, enabling differential thermal desorption and a level of upstream separation for enhanced specificity. Transitioning from 100% power and 5 s emission duration to 25% power and 30 s emission enabled an order of magnitude increase in the temporal separation (single seconds to tens of seconds) of the desorption of volatile and semi-volatile species within a collected fingerprint. This mode of operation reduced local gas-phase concentrations, reducing matrix effects experienced with high concentration mixtures. IRTD provides a unique platform for the desorption of trace analytes from wipe collections, an area of importance to the security sector, transportation agencies, and customs and border protection.

  10. Explosive turbulent magnetic reconnection.

    Science.gov (United States)

    Higashimori, K; Yokoi, N; Hoshino, M

    2013-06-21

    We report simulation results for turbulent magnetic reconnection obtained using a newly developed Reynolds-averaged magnetohydrodynamics model. We find that the initial Harris current sheet develops in three ways, depending on the strength of turbulence: laminar reconnection, turbulent reconnection, and turbulent diffusion. The turbulent reconnection explosively converts the magnetic field energy into both kinetic and thermal energy of plasmas, and generates open fast reconnection jets. This fast turbulent reconnection is achieved by the localization of turbulent diffusion. Additionally, localized structure forms through the interaction of the mean field and turbulence.

  11. Structures, mechanical properties, equations of state, and electronic properties of β-HMX under hydrostatic pressures: a DFT-D2 study.

    Science.gov (United States)

    Peng, Qing; Rahul; Wang, Guangyu; Liu, Gui-Rong; De, Suvranu

    2014-10-07

    We report the hydrostatic compression studies of the β-polymorph of a cyclotetramethylene tetranitramine (HMX) energetic molecular crystal using DFT-D2, a first-principles calculation based on density functional theory (DFT) with van der Waals (vdW) corrections. The molecular structure, mechanical properties, electronic properties, and equations of state of β-HMX are investigated. For the first time, we predict the elastic constants of β-HMX using DFT-D2 studies. The equations of state under hydrostatic compression are studied for pressures up to 100 GPa. We found that the N-N bonds along the minor axis are responsible for the sensitivity of β-HMX. The analysis of the charge distribution shows that the electronic charge is transferred from hydrogen atoms to nitro groups with the amount of 0.131 and 0.064e for the nitro groups along the minor axis and major axis, respectively, when pressure changes from 0 GPa to 100 GPa. The electronic energy band gap changes from direct at a pressure of 0 GPa to indirect at a pressure of 50 GPa and higher. The band gap decreases with respect to an increase in pressure, implying that the impact sensitivity increases with compression. Our study suggests that the van der Waals interactions are critically important in modeling the mechanical properties of this molecular crystal.

  12. Controlled by Distant Explosions

    Science.gov (United States)

    2007-03-01

    VLT Automatically Takes Detailed Spectra of Gamma-Ray Burst Afterglows Only Minutes After Discovery A time-series of high-resolution spectra in the optical and ultraviolet has twice been obtained just a few minutes after the detection of a gamma-ray bust explosion in a distant galaxy. The international team of astronomers responsible for these observations derived new conclusive evidence about the nature of the surroundings of these powerful explosions linked to the death of massive stars. At 11:08 pm on 17 April 2006, an alarm rang in the Control Room of ESO's Very Large Telescope on Paranal, Chile. Fortunately, it did not announce any catastrophe on the mountain, nor with one of the world's largest telescopes. Instead, it signalled the doom of a massive star, 9.3 billion light-years away, whose final scream of agony - a powerful burst of gamma rays - had been recorded by the Swift satellite only two minutes earlier. The alarm was triggered by the activation of the VLT Rapid Response Mode, a novel system that allows for robotic observations without any human intervention, except for the alignment of the spectrograph slit. ESO PR Photo 17a/07 ESO PR Photo 17a/07 Triggered by an Explosion Starting less than 10 minutes after the Swift detection, a series of spectra of increasing integration times (3, 5, 10, 20, 40 and 80 minutes) were taken with the Ultraviolet and Visual Echelle Spectrograph (UVES), mounted on Kueyen, the second Unit Telescope of the VLT. "With the Rapid Response Mode, the VLT is directly controlled by a distant explosion," said ESO astronomer Paul Vreeswijk, who requested the observations and is lead-author of the paper reporting the results. "All I really had to do, once I was informed of the gamma-ray burst detection, was to phone the staff astronomers at the Paranal Observatory, Stefano Bagnulo and Stan Stefl, to check that everything was fine." The first spectrum of this time series was the quickest ever taken of a gamma-ray burst afterglow

  13. Geometry-independent neutral desorption device for the sensitive EESI-MS detection of explosives on various surfaces.

    Science.gov (United States)

    Gu, Haiwei; Yang, Shuiping; Li, Jianqiang; Hu, Bin; Chen, Huanwen; Zhang, Lili; Fei, Qiang

    2010-04-01

    A novel geometry-independent neutral desorption (GIND) device was successfully developed, which made neutral desorption (ND) sampling easier and more robust on virtually all types of surfaces. The GIND device features a small air-tight enclosure with fixed space between the ND gas emitter, the sample surface, and the sample collector. Besides easy fabrication and convenient use, this configuration facilitates efficient neutral sample transfer and results in high sensitivity by preventing material loss during the ND process. The effects of various operating parameters of the GIND device such as desorption gas composition, surface wetness, gas flow rate, distance between the surface and the gas emitter, internal diameter of the sample outlet, and GIND device material were experimentally investigated. By using the GIND device, trace amounts of typical explosives such as TNT, RDX, HMX, TATP, etc., were successfully sampled from many different kinds of surfaces, including human skin, glove, glass, envelope, plastic, leather, glass, and clothes. GIND-sampled explosives were detected by multiple-stage extractive electrospray ionization mass spectrometry (EESI-MS). Ion/molecule reactions of explosives such as RDX and TATP were implemented in the EESI source for the rapid detection with enhanced sensitivity and specificity. The typical time for a single sample analysis was a few seconds. Successful transportation of the neutral analytes over a distance longer than 10 m was demonstrated, without either significant signal loss or serious delay of signal response. The limit of detection for these explosives in the study was in the range of ca. 59-842 fg (S/N = 3, n = 8) on various surfaces. Acceptable relative standard deviation (RSD) values (ca. 4.6-10.2%, n = 8) were obtained for all the surfaces tested, showing the successful sampling of trace non-volatile explosive compounds (sub-picogram) by the GIND device for the EESI mass spectrometric analysis.

  14. Laser machining of explosives

    Science.gov (United States)

    Perry, Michael D.; Stuart, Brent C.; Banks, Paul S.; Myers, Booth R.; Sefcik, Joseph A.

    2000-01-01

    The invention consists of a method for machining (cutting, drilling, sculpting) of explosives (e.g., TNT, TATB, PETN, RDX, etc.). By using pulses of a duration in the range of 5 femtoseconds to 50 picoseconds, extremely precise and rapid machining can be achieved with essentially no heat or shock affected zone. In this method, material is removed by a nonthermal mechanism. A combination of multiphoton and collisional ionization creates a critical density plasma in a time scale much shorter than electron kinetic energy is transferred to the lattice. The resulting plasma is far from thermal equilibrium. The material is in essence converted from its initial solid-state directly into a fully ionized plasma on a time scale too short for thermal equilibrium to be established with the lattice. As a result, there is negligible heat conduction beyond the region removed resulting in negligible thermal stress or shock to the material beyond a few microns from the laser machined surface. Hydrodynamic expansion of the plasma eliminates the need for any ancillary techniques to remove material and produces extremely high quality machined surfaces. There is no detonation or deflagration of the explosive in the process and the material which is removed is rendered inert.

  15. Molecular design and property prediction of high density polynitro[3.3.3]-propellane-derivatized frameworks as potential high explosives.

    Science.gov (United States)

    Zhang, Qinghua; Zhang, Jiaheng; Qi, Xiujuan; Shreeve, Jean'ne M

    2014-11-13

    Research in energetic materials is now heavily focused on the design and synthesis of novel insensitive high explosives (IHEs) for specialized applications. As an effective and time-saving tool for screening potential explosive structures, computer simulation has been widely used for the prediction of detonation properties of energetic molecules with relatively high precision. In this work, a series of new polynitrotetraoxopentaaza[3.3.3]-propellane molecules with tricyclic structures were designed. Their properties as potential high explosives including density, heats of formation, detonation properties, impact sensitivity, etc., have been extensively evaluated using volume-based thermodynamic calculations and density functional theory (DFT).These new energetic molecules exhibit high densities of >1.82 g cm(-3), in which 1 gives the highest density of 2.04 g cm(-3). Moreover, most new materials show good detonation properties and acceptable impact sensitivities, in which 5 displays much higher detonation velocity (9482 m s(-1)) and pressure (43.9 GPa) than HMX and has a h50 value of 11 cm. These results are expected to facilitate the experimental synthesis of new-generation nitramine-based high explosives.

  16. Explosive Welding for Remote Applications

    Science.gov (United States)

    Bement, L. J.

    1985-01-01

    Explosive seam welding produces up to 100-percent joint strength. Ribbon explosive activated by remote energy source produces metallurgically sound joint. Success of technique verified for joints between like metals and joints between two different metals. Applications include structural assembly in toxic atmospheres and in radioactive or otherwise hazardous environments.

  17. Active Water Explosion Suppression System

    Science.gov (United States)

    2002-06-01

    efficient in eliminating the heat of detonation , thereby eliminating the heat of combustion and the associated burning of explosive by-products in the...efficiency in eliminating the heat of detonation . In any case, the net effect of the water absorbing the detonation energy of the explosive is a major

  18. Explosive welding of undersea pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Stalker, A.W.

    1978-02-01

    The phenomenon of explosive welding has been known informally for many years. A number of investigations reported the occurerence of solid phase bonds as an incidental effect when using high explosives in association with adjacent metal surfaces and probably the earliest formal record was the observation by Carl in 1944 of a bond between two copper discs in contact with a detonator. In 1957 Philipchuk reported what is now recognized as an explosive weld between aluminium channel sections and a steel die when carrying out explosive forming trials. Since then a great deal of development work has resulted in explosive welding becoming a well established manufacturing technique, particularly in the fields of cladding and the joining of tube/tubeplates. In more recent years the process has been extended to the welding of large diameter line pipe materials.

  19. Explosive welding: Principles and potentials

    Energy Technology Data Exchange (ETDEWEB)

    Brasher, D.G.; Butler, D.J. [Northwest Technical Industries, Inc., Sequim, WA (United States)

    1995-03-01

    Explosive welding is a solid-state process in which controlled explosive detonations force two or more metals together at high pressures. The resultant composite system is joined with a high-quality metallurgical bond. Explosive welding (or explosive bonding) is a high-pressure process in which contaminant surface films are plastically jetted off the base metals as a result of the collision of two metals. The time duration involved in the explosive welding event is so short that the reaction zone (or heat affected zone) between the constituent metals is microscopic. During the process, the first few atomic layers of each metal become plasma because of the high velocity of the impact (200 to 500 m/s, 660 to 1,640 ft/s.) The angle of collision causes the plasma to jet in front of the collision point, effectively scrub-cleaning both surfaces, and leaving clean metal behind.

  20. Measurement of Low Level Explosives Reaction in the Two-Dimensional Steven Impact Test

    Energy Technology Data Exchange (ETDEWEB)

    Forbes, J.W.; Tarver, C.M.; Chidester, S.K.; Garcia, F.; Greenwood, D.W.; Garza, R.

    2000-10-10

    The two-dimensional Steven impact test has been developed to be reproducible and amenable to computer modeling. This test has a hemispherical projectile traveling at tens of m/s impacting a metal cased explosive target. To assist in the understanding of this safety test, two-dimensional shock wave gauge techniques were used to measure the pressures of a few kilobars and times of reactions less than a millisecond. This work is in accord with a long-term goal to develop two-dimensional shock diagnostic techniques that are more than just time of arrival indicators. Experiments were performed where explosives were impacted at levels below shock initiation levels but caused low level reactions. Carbon foil and carbon resistor pressure gauges were used to measure pressures and time of events. The carbon resistor gauges indicate a late time low level reaction at 350 {micro}s after impact of the hemispherical projectile creating 0.5-6 kb peak shocks at the center of PBX 9501 (HMX/Estane/BDNPA-F; 95/2.5/2.5 wt %) explosive discs. The Steven test calculations are based on an ignition and growth criteria and found that the low level reaction occurs at 335 {micro}s, which is in good agreement with the experimental data. Some additional experiments simulating the Steven impact test were done on a gas gun with carbon foil and constantan strain gauges in a PMMA target. Hydrodynamic calculations can be used to evaluate the gauge performance in these experiments and check the lateral strain measurements.

  1. The interaction of explosively generated plasma with explosives

    Science.gov (United States)

    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

  2. Mixing in explosions

    Energy Technology Data Exchange (ETDEWEB)

    Kuhl, A.L.

    1993-12-01

    Explosions always contain embedded turbulent mixing regions, for example: boundary layers, shear layers, wall jets, and unstable interfaces. Described here is one particular example of the latter, namely, the turbulent mixing occurring in the fireball of an HE-driven blast wave. The evolution of the turbulent mixing was studied via two-dimensional numerical simulations of the convective mixing processes on an adaptive mesh. Vorticity was generated on the fireball interface by baroclinic effects. The interface was unstable, and rapidly evolved into a turbulent mixing layer. Four phases of mixing were observed: (1) a strong blast wave phase; (2) and implosion phase; (3) a reshocking phase; and (4) an asymptotic mixing phase. The flowfield was azimuthally averaged to evaluate the mean and r.m.s. fluctuation profiles across the mixing layer. The vorticity decayed due to a cascade process. This caused the corresponding enstrophy parameter to increase linearly with time -- in agreement with homogeneous turbulence calculations of G.K. Batchelor.

  3. Explosion risks from nanomaterials

    Science.gov (United States)

    Bouillard, Jacques; Vignes, Alexis; Dufaud, Olivier; Perrin, Laurent; Thomas, Dominique

    2009-05-01

    Emerging nanomanufactured products are being incorporated in a variety of consumer products ranging from closer body contact products (i.e. cosmetics, sunscreens, toothpastes, pharmaceuticals, clothing) to more remote body-contact products (electronics, plastics, tires, automotive and aeronautical), hence posing potential health and environmental risks. The new field of nanosafety has emerged and needs to be explored now rather than after problems becomes so ubiquitous and difficult to treat that their trend become irreversible. Such endeavour necessitates a transdisciplinary approach. A commonly forgotten and/or misunderstood risk is that of explosion/detonation of nanopowders, due to their high specific active surface areas. Such risk is emphasized and illustrated with the present development of an appropriate risk analysis. For this particular risk, a review of characterization methods and their limitations with regard to nanopowders is presented and illustrated for a few organic and metallic nanopowders.

  4. Direct imaging of explosives

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, E.A.; Moler, R.B.; Saunders, A.W.; Trower, W.P. E-mail: trower@naxs.net

    2000-11-15

    Any technique that can detect nitrogen concentrations can screen for concealed explosives. However, such a technique would have to be insensitive to metal, both encasing and incidental. If images of the nitrogen concentrations could be captured, then, since form follows function, a robust screening technology could be developed. However these images would have to be sensitive to the surface densities at or below that of the nitrogen contained in buried anti-personnel mines or of the SEMTEX that brought down Pan Am 103, {approx}200 g. Although the ability to image in three-dimensions would somewhat reduce false positives, capturing collateral images of carbon and oxygen would virtually assure that nitrogenous non-explosive material like fertilizer, Melmac[reg] dinnerware, and salami could be eliminated. We are developing such an instrument, the Nitrogen Camera, which has met experimentally these criteria with the exception of providing oxygen images, which awaits the availability of a sufficiently energetic light source. Our Nitrogen Camera technique uses an electron accelerator to produce photonuclear reactions whose unique decays it registers. Clearly if our Nitrogen Camera is made mobile, it could be effective in detecting buried mines, either in an active battlefield situation or in the clearing of abandoned military munitions. Combat operations require that a swathe the width of an armored vehicle, 5 miles deep, be screened in an hour, which is within our camera's scanning speed. Detecting abandoned munitions is technically easier as it is free from the onerous speed requirement. We describe here our Nitrogen Camera and show its 180 pixel intensity images of elemental nitrogen in a 200 g mine simulant and in a 125 g stick of SEMTEX. We also report on our progress in creating a lorry transportable 70 MeV electron racetrack microtron, the principal enabling technology that will allow our Nitrogen Camera to be deployed in the field.

  5. Direct imaging of explosives.

    Science.gov (United States)

    Knapp, E A; Moler, R B; Saunders, A W; Trower, W P

    2000-01-01

    Any technique that can detect nitrogen concentrations can screen for concealed explosives. However, such a technique would have to be insensitive to metal, both encasing and incidental. If images of the nitrogen concentrations could be captured, then, since form follows function, a robust screening technology could be developed. However these images would have to be sensitive to the surface densities at or below that of the nitrogen contained in buried anti-personnel mines or of the SEMTEX that brought down Pan Am 103, approximately 200 g. Although the ability to image in three-dimensions would somewhat reduce false positives, capturing collateral images of carbon and oxygen would virtually assure that nitrogenous non-explosive material like fertilizer, Melmac dinnerware, and salami could be eliminated. We are developing such an instrument, the Nitrogen Camera, which has met experimentally these criteria with the exception of providing oxygen images, which awaits the availability of a sufficiently energetic light source. Our Nitrogen Camera technique uses an electron accelerator to produce photonuclear reactions whose unique decays it registers. Clearly if our Nitrogen Camera is made mobile, it could be effective in detecting buried mines, either in an active battlefield situation or in the clearing of abandoned military munitions. Combat operations require that a swathe the width of an armored vehicle, 5 miles deep, be screened in an hour, which is within our camera's scanning speed. Detecting abandoned munitions is technically easier as it is free from the onerous speed requirement. We describe here our Nitrogen Camera and show its 180 pixel intensity images of elemental nitrogen in a 200 g mine simulant and in a 125 g stick of SEMTEX. We also report on our progress in creating a lorry transportable 70 MeV electron racetrack microtron, the principal enabling technology that will allow our Nitrogen Camera to be deployed in the field.

  6. Polyurethane Binder Systems for Polymer Bonded Explosives

    Science.gov (United States)

    2006-12-01

    Weight HDI Hexamethylene diisocyanate HMX Cyclotetramethylene tetranitramine, octogen HPLC High performance liquid chromatography HTCE Hydroxy-terminated...standardised ‘VOLUCON’ potassium hydroxide (N/10) is poured into a 200 mL volumetric flask and topped up with methanol. Shake and leave to stand. 3...Titrate until the first appearance of a stable yellow colour . Titrate a blank (prepared exactly as above without adding the isocyanate

  7. Shock desensitizing of solid explosive

    Energy Technology Data Exchange (ETDEWEB)

    Davis, William C [Los Alamos National Laboratory

    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.

  8. Method and apparatus for synthesizing HMX and N/sub 2/O/sub 5/. [Patent application; cyclotetramethylenetetraamine

    Science.gov (United States)

    McGuire, R.R.; Coon, C.L.; Harrar, J.E.; Pearson, R.K.

    1982-07-20

    A method and apparatus for electrochemically synthesizing N/sub 2/O/sub 5/ includes oxidizing a solution of N/sub 2/O/sub 4//HNO/sub 3/ at an anode, while maintaining a controlled potential between the N/sub 2/O/sub 4//HNO/sub 3/ solution and the anode. A potential of about 1.35 to 2.0V vs. SCE is preferred, while a potential of about 1.80V vs. SCE is most preferred. Thereafter, the N/sub 2/O/sub 5/ is reacted with either 1.5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane (DADN) or 1,3,5,7-tetraacetyl-1,3,5,7-tetraazacyclooctane (TAT) to form cyclotetramethylenetetraamine (HMX).

  9. Active explosion barrier performance against methane and coal dust explosions

    Institute of Scientific and Technical Information of China (English)

    J J L du Plessis

    2015-01-01

    Preventing the propagation of methane or coal dust explosions through the use of active explosion-suppression systems remains one of the most underutilised explosion controls in underground coal mines. As part of the effort to develop better technologies to safeguard mines, the use of active barrier systems was investigated at Kloppersbos in South Africa. The system is designed to meet the requirements of the European Standard (EN 14591-4 2007) as well as the Mine Safety Standardisation in the Ministry of Coal Industry, Coal Industrial l Standard of the Peoples Republic of China (MT 694-1997). From the tests conducted, it can be concluded that the ExploSpot System was successful in stopping flame propagation for both methane and methane and coal dust hybrid explosions when ammonium phosphate powder was used as the suppression material. The use of this barrier will provide coal mine management with an additional explosion control close to the point of ignition and may find application within longwall faces further protecting mines against the risk of an explosion propagating throughout a mine.

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

    Science.gov (United States)

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

    2003-09-01

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

  11. 32 CFR 234.9 - Explosives.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false Explosives. 234.9 Section 234.9 National Defense... PENTAGON RESERVATION § 234.9 Explosives. (a) Using, possessing, storing, or transporting explosives, blasting agents or explosive materials is prohibited, except pursuant to the terms and conditions of a...

  12. 36 CFR 1002.38 - Explosives.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Explosives. 1002.38 Section... RECREATION § 1002.38 Explosives. (a) Using, possessing, storing, or transporting explosives, blasting agents or explosive materials is prohibited, except pursuant to the terms and conditions of a permit. When...

  13. 36 CFR 2.38 - Explosives.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Explosives. 2.38 Section 2.38... PROTECTION, PUBLIC USE AND RECREATION § 2.38 Explosives. (a) Using, possessing, storing, or transporting explosives, blasting agents or explosive materials is prohibited, except pursuant to the terms and conditions...

  14. 32 CFR 1903.9 - Explosives.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Explosives. 1903.9 Section 1903.9 National... INSTALLATIONS § 1903.9 Explosives. (a) Using, possessing, storing, or transporting explosives, blasting agents, ammunition or explosive materials is prohibited on any Agency installation, except as authorized by the...

  15. [Causation, prevention and treatment of dust explosion].

    Science.gov (United States)

    Dong, Maolong; Jia, Wenbin; Wang, Hongtao; Han, Fei; Li, Xiao-Qiang; Hu, Dahai

    2014-10-01

    With the development of industrial technology, dust explosion accidents have increased, causing serious losses of people's lives and property. With the development of economy, we should lay further emphasis on causation, prevention, and treatment of dust explosion. This article summarizes the background, mechanism, prevention, and treatment of dust explosion, which may provide some professional knowledge and reference for the treatment of dust explosion.

  16. Explosive welding finds uses offshore

    Energy Technology Data Exchange (ETDEWEB)

    1984-02-01

    This article discusses an explosive welding procedure for pipeline repair. Unlike fusion welding, explosive welding does not leave a brittle area behind and will stop axial or longitudinal cracking of a pipeline. The metals are joined by cold impact pressure, which actually liquifies the metal at the point of impact. In explosive welding, the force of the circular explosion drives the two metals together with such an impact that a bonded wave pattern is set up. All surface defects and oxides are pushed ahead of the collision front, resulting in a metal-to-metal seal. Two techniques are reviewed: the Exploweld method and the Norabel method. Both methods do not reduce or expand the internal diameter of the welded surface.

  17. Detonation probabilities of high explosives

    Energy Technology Data Exchange (ETDEWEB)

    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.

  18. Explosive Blast Neuropathology and Seizures

    Directory of Open Access Journals (Sweden)

    S. Krisztian eKovacs

    2014-04-01

    Full Text Available Traumatic brain injury (TBI due to explosive blast exposure is a leading combat casualty. It is also implicated as a key contributor to war related mental health diseases. A clinically important consequence of all types of TBI is a high risk for development of seizures and epilepsy. Seizures have been reported in patients who have suffered blast injuries in the Global War on Terror but the exact prevalence is unknown. The occurrence of seizures supports the contention that explosive blast leads to both cellular and structural brain pathology. Unfortunately, the exact mechanism by which explosions cause brain injury is unclear, which complicates development of meaningful therapies and mitigation strategies. To help improve understanding, detailed neuropathological analysis is needed. For this, histopathological techniques are extremely valuable and indispensable. In the following we will review the pathological results, including those from immunohistochemical and special staining approaches, from recent preclinical explosive blast studies.

  19. Suppression of stratified explosive interactions

    Energy Technology Data Exchange (ETDEWEB)

    Meeks, M.K.; Shamoun, B.I.; Bonazza, R.; Corradini, M.L. [Wisconsin Univ., Madison, WI (United States). Dept. of Nuclear Engineering and Engineering Physics

    1998-01-01

    Stratified Fuel-Coolant Interaction (FCI) experiments with Refrigerant-134a and water were performed in a large-scale system. Air was uniformly injected into the coolant pool to establish a pre-existing void which could suppress the explosion. Two competing effects due to the variation of the air flow rate seem to influence the intensity of the explosion in this geometrical configuration. At low flow rates, although the injected air increases the void fraction, the concurrent agitation and mixing increases the intensity of the interaction. At higher flow rates, the increase in void fraction tends to attenuate the propagated pressure wave generated by the explosion. Experimental results show a complete suppression of the vapor explosion at high rates of air injection, corresponding to an average void fraction of larger than 30%. (author)

  20. Simulation Analysis of Indoor Gas Explosion Damage

    Institute of Scientific and Technical Information of China (English)

    钱新明; 陈林顺; 冯长根

    2003-01-01

    The influence factors and process of indoor gas explosion are studied with AutoReaGas explosion simulator. The result shows that venting pressure has great influence on the indoor gas explosion damage. The higher the venting pressure is, the more serious the hazard consequence will be. The ignition location has also evident effect on the gas explosion damage. The explosion static overpressure would not cause major injury to person and serious damage to structure in the case of low venting pressure (lower than 2 kPa). The high temperature combustion after the explosion is the major factor to person injury in indoor gas explosion accidents.

  1. Furball Explosive Breakout Test

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, Joshua David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-08-05

    For more than 30 years the Onionskin test has been the primary way to study the surface breakout of a detonation wave. Currently the Onionskin test allows for only a small, one dimensional, slice of the explosive in question to be observed. Asymmetrical features are not observable with the Onionskin test and its one dimensional view. As a result, in 2011, preliminary designs for the Hairball and Furball were developed then tested. The Hairball used shorting pins connected to an oscilloscope to determine the arrival time at 24 discrete points. This limited number of data points, caused by the limited number of oscilloscope channels, ultimately led to the Hairball’s demise. Following this, the Furball was developed to increase the number of data points collected. Instead of shorting pins the Furball uses fiber optics imaged by a streak camera to determine the detonation wave arrival time for each point. The original design was able to capture the detonation wave’s arrival time at 205 discrete points with the ability to increase the number of data points if necessary.

  2. Disaster management following explosion.

    Science.gov (United States)

    Sharma, B R

    2008-01-01

    Explosions and bombings remain the most common deliberate cause of disasters involving large numbers of casualties, especially as instruments of terrorism. These attacks are virtually always directed against the untrained and unsuspecting civilian population. Unlike the military, civilians are poorly equipped or prepared to handle the severe emotional, logistical, and medical burdens of a sudden large casualty load, and thus are completely vulnerable to terrorist aims. To address the problem to the maximum benefit of mass disaster victims, we must develop collective forethought and a broad-based consensus on triage and these decisions must reach beyond the hospital emergency department. It needs to be realized that physicians should never be placed in a position of individually deciding to deny treatment to patients without the guidance of a policy or protocol. Emergency physicians, however, may easily find themselves in a situation in which the demand for resources clearly exceeds supply and for this reason, emergency care providers, personnel, hospital administrators, religious leaders, and medical ethics committees need to engage in bioethical decision-making.

  3. Numerical simulation of gas explosions

    Energy Technology Data Exchange (ETDEWEB)

    Van den Berg, A.C.; Van Wingerden, J.M.; Verhagen, T.L.

    1989-08-01

    Recent developments in numerical fluid dynamics and computer technology enable detailed simulation of gas explosions. Prins Maurits Laboratory TNO of the Netherlands Organization for Applied Scientific Research developed the necessary software. This software is a useful tool to develop and evaluate explosion safe installations. One of the possible applications is the design of save offshore rigs. (f.i. to prevent Piper Alpha disasters). The two-dimensional blast model is described and an example is given. 4 figs., 6 refs.

  4. System for analysis of explosives

    Science.gov (United States)

    Haas, Jeffrey S [San Ramon, CA

    2010-06-29

    A system for analysis of explosives. Samples are spotted on a thin layer chromatography plate. Multi-component explosives standards are spotted on the thin layer chromatography plate. The thin layer chromatography plate is dipped in a solvent mixture and chromatography is allowed to proceed. The thin layer chromatography plate is dipped in reagent 1. The thin layer chromatography plate is heated. The thin layer chromatography plate is dipped in reagent 2.

  5. Intraperitoneal explosion following gastric perforation.

    Science.gov (United States)

    Mansfield, Scott K; Borrowdale, Roderick

    2014-04-01

    The object of this study is to report a rare case of explosion during laparotomy where diathermy ignited intraperitoneal gas from a spontaneous stomach perforation. Fortunately, the patient survived but the surgeon experienced a finger burn. A literature review demonstrates other examples of intraoperative explosion where gastrointestinal gases were the fuel source. Lessons learned from these cases provide recommendations to prevent this potentially lethal event from occurring.

  6. Development of highly sensitive and selective antibodies for the detection of the explosive pentaerythritol tetranitrate (PETN) by bioisosteric replacement.

    Science.gov (United States)

    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.

  7. Tertiary Treatment of Effluent from Holston AAP (Army Ammunition Plant) Industrial Liquid Waste Treatment Facility. 4. Ultraviolet Radiation and Hydrogen Peroxide Studies: TNT, RDX, HMX, TAX, and SEX

    Science.gov (United States)

    1984-03-01

    AAP Technical Report INDUSTRIAL LIQUID WASTE TREATMENT FACILITY Feb 1983 - Aug 1983 IV. ULTRAVIOLET RADIATION AND HYDROGEN PEROXIDE 1. PERPnRUINe ORO ...ultraviolet light. The production of nitrate-nitrogen and loss of total organic carbon was reportedly indicative of the mineralization of TNT. 5...Treatment of Effluent from Holston AAP Industrial Liquid Waste Treatment Facility. II. Corona Oxidation Studies: TNT, RDX, HMX, TAX, and SEX. Technical

  8. A 3-D microstructural level model for analyzing the response of polymer bonded explosives

    Science.gov (United States)

    Hardin, David; Zhou, Min

    2011-06-01

    A three-dimensional finite element model is developed to study the microstructural level response of polymer-bonded explosives (PBX) under impact loading. The study focuses on the effect of the morphology and packing of energetic grains on the overall thermomechanical response of the composites. A cohesive finite element method (CFEM) is utilized to account for failure in the form of debonding between the HMX grains and the polymer matrix. Frictional heating along crack faces is tracked through a contact algorithm. Microstructures with cubic and multifaceted three-dimensional polygonal granules with packing densities between 0.42 and 0.74 are generated and used. Both 2D and 3D calculations are carried to analyze the differences between the models. To ensure consistency, the 2D microstructures are sections of the 3D microstructures. In this presentation, we will discuss differences in results from the 2D and 3D calculations, with a particular focus on the progression of damage and heating under impact loading.

  9. Meso-scale analysis of deformation wave heating in metalized solid explosive

    Directory of Open Access Journals (Sweden)

    Gonthier K.A.

    2011-01-01

    Full Text Available Deformation induced heating of reactive solids is a physically complex process. As such, the effects of meso-structure, component thermomechanical properties, component mass fractions, and porosity on their impact response is not well-understood. In this study, an explicit, 2-D, Lagrangian finite and discrete element technique is used to examine thermomechanical fields in metal-explosive (aluminum-HMX particle mixtures due to piston supported uniaxial deformation waves. The meso-scale description uses a plane strain, thermoelastic-viscoplastic and friction constitutive theory to describe the motion and deformation of individual particles, and an energy consistent, penalty based method to describe inter-particle contact. The deformation response of material having an initial solid volume fraction of ΦS0 = 0.835 is characterized for different metal mass fractions and wave strengths. Predictions indicate that the response can be classified into strength dominated and pressure dominated regions depending on wave strength. Average thermomechanical fields that define the macro-scale wave structure are found to differ both qualitatively and quantitatively between the two regions.

  10. Molecular Outflows: Explosive versus Protostellar

    Science.gov (United States)

    Zapata, Luis A.; Schmid-Burgk, Johannes; Rodríguez, Luis F.; Palau, Aina; Loinard, Laurent

    2017-02-01

    With the recent recognition of a second, distinctive class of molecular outflows, namely the explosive ones not directly connected to the accretion–ejection process in star formation, a juxtaposition of the morphological and kinematic properties of both classes is warranted. By applying the same method used in Zapata et al., and using 12CO(J = 2-1) archival data from the Submillimeter Array, we contrast two well-known explosive objects, Orion KL and DR21, to HH 211 and DG Tau B, two flows representative of classical low-mass protostellar outflows. At the moment, there are only two well-established cases of explosive outflows, but with the full availability of ALMA we expect that more examples will be found in the near future. The main results are the largely different spatial distributions of the explosive flows, consisting of numerous narrow straight filament-like ejections with different orientations and in almost an isotropic configuration, the redshifted with respect to the blueshifted components of the flows (maximally separated in protostellar, largely overlapping in explosive outflows), the very-well-defined Hubble flow-like increase of velocity with distance from the origin in the explosive filaments versus the mostly non-organized CO velocity field in protostellar objects, and huge inequalities in mass, momentum, and energy of the two classes, at least for the case of low-mass flows. Finally, all the molecular filaments in the explosive outflows point back to approximately a central position (i.e., the place where its “exciting source” was located), contrary to the bulk of the molecular material within the protostellar outflows.

  11. THE INFLUENCE OF BARRIERS ON FLAME AND EXPLOSION WAVE IN GAS EXPLOSION

    Institute of Scientific and Technical Information of China (English)

    林柏泉; 周世宁; 张仁贵

    1998-01-01

    This paper researches into the influence of barriers on flame and explosion wave in gasexplosion on the basis of experiment. The result shows that the barrier is very important to thetransmission of flame and explosion wave in gas explosion. When there are barriers, the speed oftransmission would be very fast and shock wave will appear in gas explosion, which would in-crease gas explosion power. The result of research is very important to prevent gas explosion anddecrease the power of it.

  12. The Nkx5/HMX homeodomain protein MLS-2 is required for proper tube cell shape in the C. elegans excretory system.

    Science.gov (United States)

    Abdus-Saboor, Ishmail; Stone, Craig E; Murray, John I; Sundaram, Meera V

    2012-06-15

    Cells perform wide varieties of functions that are facilitated, in part, by adopting unique shapes. Many of the genes and pathways that promote cell fate specification have been elucidated. However, relatively few transcription factors have been identified that promote shape acquisition after fate specification. Here we show that the Nkx5/HMX homeodomain protein MLS-2 is required for cellular elongation and shape maintenance of two tubular epithelial cells in the C. elegans excretory system, the duct and pore cells. The Nkx5/HMX family is highly conserved from sea urchins to humans, with known roles in neuronal and glial development. MLS-2 is expressed in the duct and pore, and defects in mls-2 mutants first arise when the duct and pore normally adopt unique shapes. MLS-2 cooperates with the EGF-Ras-ERK pathway to turn on the LIN-48/Ovo transcription factor in the duct cell during morphogenesis. These results reveal a novel interaction between the Nkx5/HMX family and the EGF-Ras pathway and implicate a transcription factor, MLS-2, as a regulator of cell shape.

  13. Chemical kinetics of Estane aging in PBX

    Energy Technology Data Exchange (ETDEWEB)

    Pack, R.T.; Hanson, D.E.; Redondo, A. [Los Alamos National Lab., NM (United States). Theoretical Div.

    1997-12-01

    The Plastic-Bonded Explosive PBX 9501 is about 95% HMX, 2.5% Estane 5703, 2.5% nitroplasticizer (NP), and 0.1% stabilizer by weight. The NP, BDNPA/F, is a eutectic mixture of bis(2,2-dinitropropyl) acetal and bis(2,2-dinitropropyl)formal. The stabilizer is diphenylamine (DPA) or Irganox 1010. The Estane, a polyester-polyurethane, slowly degrades with time. Knowledge of the effect of the Estane aging on the mechanical properties of the PBX 9501 is required to predict with confidence the useful lifetime of the explosive with respect to safety and reliability. A detailed master equation model of the chemical mechanisms and kinetics of the aging of Estane 5703 in PBX 9501 is being developed. Its output will be used as input into other models being developed to calculate the changes in the mechanical properties of the PBX.

  14. Modeling the mechanics of HMX detonation using a Taylor–Galerkin scheme

    Directory of Open Access Journals (Sweden)

    Adam V. Duran

    2016-05-01

    Full Text Available Design of energetic materials is an exciting area in mechanics and materials science. Energetic composite materials are used as propellants, explosives, and fuel cell components. Energy release in these materials are accompanied by extreme events: shock waves travel at typical speeds of several thousand meters per second and the peak pressures can reach hundreds of gigapascals. In this paper, we develop a reactive dynamics code for modeling detonation wave features in one such material. The key contribution in this paper is an integrated algorithm to incorporate equations of state, Arrhenius kinetics, and mixing rules for particle detonation in a Taylor–Galerkin finite element simulation. We show that the scheme captures the distinct features of detonation waves, and the detonation velocity compares well with experiments reported in literature.

  15. Thermodynamic States in Explosion Fields

    Energy Technology Data Exchange (ETDEWEB)

    Kuhl, A L

    2009-10-16

    Here we investigate the thermodynamic states occurring in explosion fields from the detonation of condensed explosives in air. In typical applications, the pressure of expanded detonation products gases is modeled by a Jones-Wilkins-Lee (JWL) function: P{sub JWL} = f(v,s{sub CJ}); constants in that function are fit to cylinder test data. This function provides a specification of pressure as a function of specific volume, v, along the expansion isentrope (s = constant = s{sub CJ}) starting at the Chapman-Jouguet (CJ) state. However, the JWL function is not a fundamental equation of thermodynamics, and therefore gives an incomplete specification of states. For example, explosions inherently involve shock reflections from surfaces; this changes the entropy of the products, and in such situations the JWL function provides no information on the products states. In addition, most explosives are not oxygen balanced, so if hot detonation products mix with air, they after-burn, releasing the heat of reaction via a turbulent combustion process. This raises the temperature of explosion products cloud to the adiabatic flame temperature ({approx}3,000K). Again, the JWL function provides no information on the combustion products states.

  16. Explosion limits for combustible gases

    Institute of Scientific and Technical Information of China (English)

    TONG Min-ming; WU Guo-qing; HAO Ji-fei; DAI Xin-lian

    2009-01-01

    Combustible gases in coal mines are composed of methane, hydrogen, some multi-carbon alkane gases and other gases. Based on a numerical calculation, the explosion limits of combustible gases were studied, showing that these limits are related to the concentrations of different components in the mixture. With an increase of C4H10 and C6H14, the Lower ExplosionLimit (LEL) and Upper Explosion-Limit (UEL) of a combustible gas mixture will decrease clearly. For every 0.1% increase in C4H10 and C6H14, the LEL decreases by about 0.19% and the UEL by about 0.3%. The results also prove that, by increasing the amount of H2, the UEL of a combustible gas mixture will increase considerably. If the level of H2 increases by 0.1%, the UEL will increase by about 0.3%. However, H2 has only a small effect on the LEL of the combustible gas mixture. Our study provides a theoretical foundation for judging the explosion risk of an explosive gas mixture in mines.

  17. Explosion and explosives. Volume 32, Number 5, 1971

    Energy Technology Data Exchange (ETDEWEB)

    1976-01-01

    The following topics are discussed: CMDB propellants with high pressure exponent; the thermal decomposition of phenylnitromethane in 2-propanol; double exposed flash x-ray photographic observation on detonation of coal mining explosions; detonation of condensed multiple components about detonation characteristics of three liquid explosives; synthesis of N,N'-bis (2,4,6-trinitro-3-glycidoxyphenyl)-ethylene dinitramine; resistance characteristics of electric primer containing conductive particles; and formation of Meisenheimer's complex by adding an aqueous sodium hydroxide to the reaction product of epoxy compound with picric acid.

  18. Thermal decomposition and kinetics of 2,4-dinitroimidazole: An insensitive high explosive

    Energy Technology Data Exchange (ETDEWEB)

    Anniyappan, M., E-mail: anniorganic@rediffmail.com; Sonawane, S.H.; Pawar, S.J.; Sikder, A.K.

    2015-08-20

    Highlights: • Pure 2,4-dinitroimidazole was prepared by re-crystallization from hot methanol. • A detailed thermal analysis of 2,4-DNI by DSC, TGA, GC–MS and ignition temperature. • Activation energy was calculated for thermal decomposition of 2,4-DNI • Effect of polymeric binder on thermal decomposition of 2,4-DNI were also studied. • Decomposition mechanisms of 2,4-DNI based on EI mass spectra were also described. - Abstract: 2,4-Dinitroimidazole (2,4-DNI) is a novel energetic material with much less sensitive and potential for use as a propellant/insensitive munition (IM) formulations. 2,4-DNI possess high thermal stability and less sensitivity as compared to RDX and HMX which are high explosives extensively used at present. This paper reports a detailed thermal study of 2,4-DNI using various instrumental techniques. The activation energy (E = 205 ± 15 kJ/mol) was calculated from thermal decomposition of 2,4-DNI using DSC at different heating rate. The ignition temperature of pure 2,4-DNI was measured and showed at 285 °C. The TGA experiments demonstrate that 2,4-DNI decomposes in three steps with 92% total weight lose. Moreover, the effect of thermal energy on decomposition of 2,4-DNI in presence of polymeric binders like GAP and HTPB were investigated. Further, decomposition mechanisms of 2,4-DNI based on Electron Impact mass spectra analysis were also reported along with its explosive properties.

  19. The Quiet Explosion

    Science.gov (United States)

    2008-07-01

    A European-led team of astronomers are providing hints that a recent supernova may not be as normal as initially thought. Instead, the star that exploded is now understood to have collapsed into a black hole, producing a weak jet, typical of much more violent events, the so-called gamma-ray bursts. The object, SN 2008D, is thus probably among the weakest explosions that produce very fast moving jets. This discovery represents a crucial milestone in the understanding of the most violent phenomena observed in the Universe. Black Hole ESO PR Photo 23a/08 A Galaxy and two Supernovae These striking results, partly based on observations with ESO's Very Large Telescope, will appear tomorrow in Science Express, the online version of Science. Stars that were at birth more massive than about 8 times the mass of our Sun end their relatively short life in a cosmic, cataclysmic firework lighting up the Universe. The outcome is the formation of the densest objects that exist, neutron stars and black holes. When exploding, some of the most massive stars emit a short cry of agony, in the form of a burst of very energetic light, X- or gamma-rays. In the early afternoon (in Europe) of 9 January 2008, the NASA/STFC/ASI Swift telescope discovered serendipitously a 5-minute long burst of X-rays coming from within the spiral galaxy NGC 2770, located 90 million light-years away towards the Lynx constellation. The Swift satellite was studying a supernova that had exploded the previous year in the same galaxy, but the burst of X-rays came from another location, and was soon shown to arise from a different supernova, named SN 2008D. Researchers at the Italian National Institute for Astrophysics (INAF), the Max-Planck Institute for Astrophysics (MPA), ESO, and at various other institutions have observed the supernova at great length. The team is led by Paolo Mazzali of INAF's Padova Observatory and MPA. "What made this event very interesting," says Mazzali, "is that the X-ray signal was very

  20. Optimal dynamic detection of explosives

    Energy Technology Data Exchange (ETDEWEB)

    Moore, David Steven [Los Alamos National Laboratory; Mcgrane, Shawn D [Los Alamos National Laboratory; Greenfield, Margo T [Los Alamos National Laboratory; Scharff, R J [Los Alamos National Laboratory; Rabitz, Herschel A [PRINCETON UNIV; Roslund, J [PRINCETON UNIV

    2009-01-01

    The detection of explosives is a notoriously difficult problem, especially at stand-off distances, due to their (generally) low vapor pressure, environmental and matrix interferences, and packaging. We are exploring optimal dynamic detection to exploit the best capabilities of recent advances in laser technology and recent discoveries in optimal shaping of laser pulses for control of molecular processes to significantly enhance the standoff detection of explosives. The core of the ODD-Ex technique is the introduction of optimally shaped laser pulses to simultaneously enhance sensitivity of explosives signatures while reducing the influence of noise and the signals from background interferents in the field (increase selectivity). These goals are being addressed by operating in an optimal nonlinear fashion, typically with a single shaped laser pulse inherently containing within it coherently locked control and probe sub-pulses. With sufficient bandwidth, the technique is capable of intrinsically providing orthogonal broad spectral information for data fusion, all from a single optimal pulse.

  1. Coulomb explosion of "hot spot"

    CERN Document Server

    Oreshkin, V I; Chaikovsky, S A; Artyomov, A P

    2016-01-01

    The study presented in this paper has shown that the generation of hard x rays and high-energy ions, which are detected in pinch implosion experiments, may be associated with the Coulomb explosion of the hot spot that is formed due to the outflow of the material from the pinch cross point. During the process of material outflow, the temperature of the hot spot plasma increases, and conditions arise for the plasma electrons to become continuously accelerated. The runaway of electrons from the hot spot region results in the buildup of positive space charge in this region followed by a Coulomb explosion. The conditions for the hot spot plasma electrons to become continuously accelerated have been revealed and estimates have been obtained for the kinetic energy of the ions generated by the Coulomb explosion.

  2. Instrument safety in explosive atmospheres.

    Science.gov (United States)

    Bossert, J A

    1975-01-01

    The current "Energy Crisis" has dramatically increased our potential need for coal, the worlds most abundant fossil fuel. This will probably lead to a greater use of automation and instrumentation in the coal mining industry. The presence of methane in coal mines and in the coal itself plus the presence of coal dust, both of which can form an explosive atmosphere in air, means that the possibility of a gas or coal dust ignition must be considered when designing, purchasing and installing new equipment in this industry. In addition, many metallurgical processes involve the use of potentially explosive substances against which similar safety precautions must be taken. This paper outlines the various methods of protection currently in use and proposed for electrical instruments in explosive atmospheres, with particular emphasis on the work of the International Electrotechnical Commission.

  3. Evidence for Nearby Supernova Explosions

    CERN Document Server

    Benítez, N; Canelles, M; Benitez, Narciso; Maiz-Apellaniz, Jesus; Canelles, Matilde

    2002-01-01

    Supernova explosions are one of the most energetic--and potentially lethal--phenomena in the Universe. Scientists have speculated for decades about the possible consequences for life on Earth of a nearby supernova, but plausible candidates for such an event were lacking. Here we show that the Scorpius-Centaurus OB association, a group of young stars currently located at~130 parsecs from the Sun, has generated 20 SN explosions during the last 11 Myr, some of them probably as close as 40 pc to our planet. We find that the deposition on Earth of 60Fe atoms produced by these explosions can explain the recent measurements of an excess of this isotope in deep ocean crust samples. We propose that ~2 Myr ago, one of the SNe exploded close enough to Earth to seriously damage the ozone layer, provoking or contributing to the Pliocene-Pleistocene boundary marine extinction.

  4. Explosively Joining Dissimilar Metal Tubes.

    Science.gov (United States)

    1979-11-01

    both steel, photograph (7), and the Ni-Cu specimen, photograph (8) , showed considerable pitting corrosion in the aluminum . 4. The paint was then...for 6061 -T6 aluminum and are: collision angle 5 - 200, collision velocity 270 - 350 m/sec, with an impact pressure of at least 27 Kbar (391 Kpsi...Welded Aluminum Alloy 1 .. 5 rn-i (P0 -I Op. 2si 11 6W TABLE I Explosive2 Cladder Metal Base Metal Explosive Loading (gins/in2 6061 -T6 Al 304 SS TSE- 1004

  5. Intravesical explosion during transurethral electrosurgery.

    Science.gov (United States)

    Georgios, Kallinikas; Evangelos, Boulinakis; Helai, Habib; Ioannis, Gerzelis

    2015-05-01

    Intravesical explosion is a very rare complication of transurethral resection of prostate and transurethral resection of bladder tumour operations. In vitro studies have shown that the gases produced during the procedure could result in a blast once they are mixed with air from the atmosphere. A 79-year-old male experienced an explosion in his bladder while undergoing a transurethral resection of bladder tumour. The case is presented as well as the way that it was treated as an emergency. Precautions of such events are finally suggested.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-12-01

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

  7. Halogenated Explosives to Defeat Biological Agents

    Science.gov (United States)

    2015-09-01

    of TFM-RDX were carried out using Cheetah 6.0 code by estimating a density of TFM-RDX, which had not been reported as experimentally measured...HMX (1.861 g∙cm−3).35 The density of TFM-RDX (1), needed for Cheetah calculations, was preliminarily estimated by adding three-quarters of the overall...enhancement of those four CF3 groups (0.323 g∙cm−3) to the known density of RDX: ρ(TFM-RDX) ~ 1.816 + ¾(0.323) ≈ 2.06 g∙cm−3. Then Cheetah

  8. 46 CFR 188.10-25 - Explosive.

    Science.gov (United States)

    2010-10-01

    ... mixture, the primary purpose of which is to function by explosion; i.e., with substantially instantaneous release of gas and heat. Explosives are discussed in more detail in 49 CFR parts 171-179....

  9. New Source Model for Chemical Explosions

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiaoning [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-03

    With sophisticated inversion scheme, we recover characteristics of SPE explosions such as corner frequency fc and moment M0, which are used to develop a new source model for chemical explosions.

  10. Pulmonary contusion and hemothorax due to explosion

    National Research Council Canada - National Science Library

    Baeza-Herrera, Carlos; Sanjuán-Fabián, Héctor; Medellín-Sierra, Ulises Darío; Nájera-Garduño, Heladio; García-Cabello, Luis Manuel

    2006-01-01

    .... Such is the case of gunpowder explosive objects used during celebration holidays. We present a 14-year-old male who suffered a pulmonary contusion as a consequence of an explosion of "huevo de codorniz...

  11. The behavior limestone under explosive load

    Science.gov (United States)

    Orlov, M. Yu; Orlova, Yu N.; Bogomolov, G. N.

    2016-11-01

    Limestone behavior under explosive loading was investigated. The behavior of the limestone by the action of the three types of explosives, including granular, ammonite and emulsion explosives was studied in detail. The shape and diameter of the explosion craters were obtained. The observed fragments after the blast have been classified as large, medium and small fragments. Three full-scale experiments were carried out. The research results can be used as a qualitative test for the approbation of numerical methods.

  12. Gas Explosions Mitigation by Ducted Venting

    OpenAIRE

    2007-01-01

    The mitigation of effects of gas and dust explosions within industrial equipment is effective if venting the combustion products to safe location. The presence of relief duct is however likely to increase the severity of the explosion with respect to equipment vented to open atmosphere, due to secondary explosions occurring in the initial sections of duct, frictional drag and inertia of the gas column, acoustic and Helmholtz oscillations. The weights of these phenomena on explosion e...

  13. Statistical estimation of loads from gas explosions

    OpenAIRE

    Høiset, Stian

    1998-01-01

    In the design of structures in the offshore and process industries, the possibility of a gas explosion must always be considered. This is usually incorporated by performing explosion simulations. However, estimations based on such calculations introduce uncertainties in the design process. The main uncertainties in explosion simulations are the assumption of the gas cloud,the location of the ignition point and the properties of the explosion simulator itself. In this thesis, we try to investi...

  14. 75 FR 70291 - Commerce in Explosives; List of Explosive Materials (2010R-27T)

    Science.gov (United States)

    2010-11-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF JUSTICE Bureau of Alcohol, Tobacco, Firearms and Explosives Commerce in Explosives; List of Explosive Materials (2010R-27T) AGENCY: Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), Department of...

  15. 77 FR 58410 - Commerce in Explosives; List of Explosive Materials (2012R-10T)

    Science.gov (United States)

    2012-09-20

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF JUSTICE Bureau of Alcohol, Tobacco, Firearms, and Explosives Commerce in Explosives; List of Explosive Materials (2012R-10T) AGENCY: Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF), Department of...

  16. 76 FR 64974 - Commerce in Explosives; List of Explosive Materials (2011R-18T)

    Science.gov (United States)

    2011-10-19

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF JUSTICE Bureau of Alcohol, Tobacco, Firearms and Explosives Commerce in Explosives; List of Explosive Materials (2011R-18T) AGENCY: Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), Department of...

  17. Explosive micro-bubble actuator

    NARCIS (Netherlands)

    Broek, van den D.M.; Elwenspoek, M.

    2008-01-01

    Explosive evaporation occurs when a liquid is exposed to extremely high heat-fluxes. Within a few microseconds a bubble in the form vapour film is generated, followed by rapid growth due to the pressure impulse and finally the bubbles collapse. This effect, which already has proven its use in curren

  18. Explosive micro-bubble actuator

    NARCIS (Netherlands)

    Broek, van den D.M.; Elwenspoek, M.C.

    2007-01-01

    Explosive evaporation occurs when a thin layer of liquid reaches a very high temperature in a very short time. At these temperatures homogeneous nucleation takes place. The nucleated bubbles almost instantly coalesce forming a vapour film followed by rapid growth due to the pressure impulse and fina

  19. Measuring explosive non-ideality

    Energy Technology Data Exchange (ETDEWEB)

    Souers, P C

    1999-02-17

    The sonic reaction zone length may be measured by four methods: (1) size effect, (2) detonation front curvature, (3) crystal interface velocity and (4) in-situ gauges. The amount of data decreases exponentially from (1) to (4) with there being almost no gauge data for prompt detonation at steady state. The ease and clarity of obtaining the reaction zone length increases from (1) to (4). The method of getting the reaction zone length, , is described for the four methods. A measure of non-ideality is proposed: the reaction zone length divided by the cylinder radius. N = /R{sub o}. N = 0 for true ideality. It also decreases with increasing radius as it should. For N < 0.10, an equilibrium EOS like the JWL may be used. For N > 0.10, a time-dependent description is essential. The crystal experiment, which measures the particle velocity of an explosive-transparent material interface, is presently rising in importance. We examine the data from three experiments and apply: (1) an impedance correction that transfers the explosive C-J particle velocity to the corresponding value for the interface, and (2) multiplies the interface time by 3/4 to simulate the explosive speed of sound. The result is a reaction zone length comparable to those obtained by other means. A few explosives have reaction zones so small that the change of slope in the particle velocity is easily seen.

  20. Explosion mitigation by water mist

    NARCIS (Netherlands)

    Wal, R. van der; Cargill, S.; Longbottom, A.; Rhijnsburger, M.P.M.; Erkel, A.G. van

    2010-01-01

    The internal explosion of an anti-ship missile or stored ammunition is a potentially catastrophic threat for a navy vessel. These events generally cause heavy blast loading and fragments to perforate the ship structure. As a solution to reduce the blast loading, the compartment can be filled with

  1. Lead-free primary explosives

    Science.gov (United States)

    Huynh, My Hang V.

    2010-06-22

    Lead-free primary explosives of the formula (cat).sub.Y[M.sup.II(T).sub.X(H.sub.2O).sub.6-X].sub.Z, where T is 5-nitrotetrazolate, and syntheses thereof are described. Substantially stoichiometric equivalents of the reactants lead to high yields of pure compositions thereby avoiding dangerous purification steps.

  2. Turbulent Combustion in SDF Explosions

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-11-12

    A heterogeneous continuum model is proposed to describe the dispersion and combustion of an aluminum particle cloud in an explosion. It combines the gas-dynamic conservation laws for the gas phase with a continuum model for the dispersed phase, as formulated by Nigmatulin. Inter-phase mass, momentum and energy exchange are prescribed by phenomenological models. It incorporates a combustion model based on the mass conservation laws for fuel, air and products; source/sink terms are treated in the fast-chemistry limit appropriate for such gasdynamic fields, along with a model for mass transfer from the particle phase to the gas. The model takes into account both the afterburning of the detonation products of the C-4 booster with air, and the combustion of the Al particles with air. The model equations were integrated by high-order Godunov schemes for both the gas and particle phases. Numerical simulations of the explosion fields from 1.5-g Shock-Dispersed-Fuel (SDF) charge in a 6.6 liter calorimeter were used to validate the combustion model. Then the model was applied to 10-kg Al-SDF explosions in a an unconfined height-of-burst explosion. Computed pressure histories are compared with measured waveforms. Differences are caused by physical-chemical kinetic effects of particle combustion which induce ignition delays in the initial reactive blast wave and quenching of reactions at late times. Current simulations give initial insights into such modeling issues.

  3. Optical Pressure Measurements of Explosions

    Science.gov (United States)

    2013-09-01

    Explosive Shocks in Air, 2nd ed.; Springer-Verlag: Berlin , Germany, 1985. 7. Anderson, J. D. Hypersonic and High Temperature Gas Dynamics, 2nd Ed...PDF) RDRL CIO LA T LANDFRIED RDRL WML M ZOLTOSKI RDRL WML A F DE LUCIA W OBERLE RDRL WML B J GOTTFRIED J CIEZAK

  4. MECHANISM OF EXPLOSIVE WELDING OF METALS

    OpenAIRE

    Sek, W.

    1988-01-01

    Mechanism of explosive welding is discussed. The experimental date indicate that the explosive bonding interface forms behind the collision point and the physical properties of metals affect considerably this process. The usefulness of hydrodynamic model for describing the explosive welding process is called in question.

  5. 14 CFR 420.63 - Explosive siting.

    Science.gov (United States)

    2010-01-01

    ... Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... site plan shall include: (1) A scaled map that shows the location of all proposed explosive hazard... explosive hazard facility and all other explosive hazard facilities and each public area, including...

  6. 30 CFR 77.1301 - Explosives; magazines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Explosives; magazines. 77.1301 Section 77.1301... and Blasting § 77.1301 Explosives; magazines. (a) Detonators and explosives other than blasting agents shall be stored in magazines. (b) Detonators shall not be stored in the same magazine with...

  7. 49 CFR 173.54 - Forbidden explosives.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Forbidden explosives. 173.54 Section 173.54... SHIPMENTS AND PACKAGINGS Definitions, Classification and Packaging for Class 1 § 173.54 Forbidden explosives. Unless otherwise provided in this subchapter, the following explosives shall not be offered for...

  8. 46 CFR 147.95 - Explosives.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Explosives. 147.95 Section 147.95 Shipping COAST GUARD... Special Requirements for Particular Materials § 147.95 Explosives. (a) Explosives—general. Except as provided for elsewhere in this subchapter, explosives, as defined in 49 CFR 173.50, which are hazardous...

  9. 46 CFR 153.921 - Explosives.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Explosives. 153.921 Section 153.921 Shipping COAST GUARD....921 Explosives. No person may load, off-load, or carry a cargo listed in this part on board a vessel that carries explosives unless he has the prior written permission of the Commandant (CG-522). ...

  10. Portable SERS Instrument for Explosives Monitoring

    Science.gov (United States)

    2008-01-01

    groundwater monitoring from a cone penetrometer (CPT) platform (5) Demonstrate improved capability for discriminating explosives versus colorimetry ...interference, and better discrimination of individual explosives compared to colorimetry • Applicability to virtually any environmental water...chemicals such as nitroaromatics or nitramines. While this makes colorimetry more generally applicable at explosive sites, it also limits the ability to

  11. Scientific Support for NQR Explosive Detection Development

    Science.gov (United States)

    2006-07-01

    Final 3. DATES COVERED (From - To) 8 March 2004 - 7 March 2006 4. TITLE AND SUBTITLE Scientific Support for NQR Explosive Detection Development...Laboratory (NRL) to improve explosive detection using nuclear quadrupole resonance ( NQR ) is summarized. The work includes studies of the effects...superconducting coils for explosive detection. Additional studies involving slowly rotating NQR measurements were also pursued. 15. SUBJECT TERMS Nuclear

  12. Explosion Power and Pressure Desensitization Resisting Property of Emulsion Explosives Sensitized by MgH2

    Science.gov (United States)

    Cheng, Yangfan; Ma, Honghao; Liu, Rong; Shen, Zhaowu

    2014-07-01

    Due to low detonation power and pressure desensitization problems that traditional emulsion explosives encounter in utilization, a hydrogen-based emulsion explosives was devised. This type of emulsion explosives is sensitized by hydrogen-containing material MgH2, and MgH2 plays a double role as a sensitizer and an energetic material in emulsion explosives. Underwater explosion experiments and shock wave desensitization experiments show that an MgH2 emulsion explosives has excellent detonation characteristics and is resistant to pressure desensitization. The pressure desensitization-resistant mechanism of MgH2 emulsion explosives was investigated using scanning electron microscopy.

  13. Numerical computation algorithm of explosion equations and thermodynamics parameters of mine explosives

    Institute of Scientific and Technical Information of China (English)

    李守巨; 刘迎曦; 何翔; 周圆π

    2001-01-01

    A new numerical algorithm is presented to simulate the explosion reaction process of mine explosives based on the equation of state, the equation of mass conservation and thermodynamics balance equation of explosion products. With the affection of reversible reaction of explosion products to explosion reaction equations and thermodynamics parameters considered, the computer program has been developed. The computation values show that computer simulation results are identical with the testinq ones.

  14. Numerical computation algorithm of explosion equations and thermodynamics parameters of mine explosives

    Institute of Scientific and Technical Information of China (English)

    LI Shou-ju; LIU Ying-xi; HE Xiang; ZHOU Y uan-pai

    2001-01-01

    A new numerical algorithm is presented to simulate the explosion reacti on process of mine explosives based on the equation of state, the equation of ma ss conservation and thermodynamics balance equation of explosion products. With the affection of reversible reaction of explosion products to explosion reaction equations and thermodynamics parameters considered, the computer program has be en developed. The computation values show that computer simulation results are i dentical with the testing ones.

  15. Gas explosions - an elementary account; Eksplosiv fare

    Energy Technology Data Exchange (ETDEWEB)

    Seehusen, Joachim

    2002-07-01

    Although in a typical gas explosion the flame front propagates at sub-sonic speed, it still moves fast. Safety people often believe they can run away from a gas explosion. While gas explosions are well understood in the major companies, this is not true in many small ones, and people often do not realise how small the difference may be between a small puff and a dangerous explosion. Of special interest in a ''hydrogen society'' is the fact that hydrogen is dangerous and must be handled with care. The article discusses in an elementary way some of the basic concepts from the physics of gas explosions.

  16. Damage Effects of Shelled Explosive Explosion in Concrete

    Directory of Open Access Journals (Sweden)

    Liu Yan

    2010-10-01

    Full Text Available The damage of concrete subjected to explosion loading is an important issue in defense engineering. The damage degree of concrete is related to many factors, such as the type of explosive charge, the depth of burial and the parameters of concrete. In this paper, three factors are considered for experiments of shelled explosives in concrete targets, which are the filling coefficient, length-to-diameter ratio and the depth of burial. The filling coefficient is from 0.1 to 1 by changing thickness of shell, and length-to-diameter ratio is from 2.5 to 10. The unconfined compressive strength of concrete target for test is 35MPa. The experimental results showed that the sizes of craters of concretes are varied as the filling coefficient, length-to-diameter ratio and the depth of burial. The optimal values of filling coefficient, length-to-diameter ratio and the depth of burial of shelled charges were obtained to get largest damage regions of concrete targets. This work provides a base for evaluating the damage of concrete and designing the penetrating warhead.Defence Science Journal, 2010, 60(6, pp.672-677, DOI:http://dx.doi.org/10.14429/dsj.60.434

  17. Spot test kit for explosives detection

    Science.gov (United States)

    Pagoria, Philip F; Whipple, Richard E; Nunes, Peter J; Eckels, Joel Del; Reynolds, John G; Miles, Robin R; Chiarappa-Zucca, Marina L

    2014-03-11

    An explosion tester system comprising a body, a lateral flow membrane swab unit adapted to be removeably connected to the body, a first explosives detecting reagent, a first reagent holder and dispenser operatively connected to the body, the first reagent holder and dispenser containing the first explosives detecting reagent and positioned to deliver the first explosives detecting reagent to the lateral flow membrane swab unit when the lateral flow membrane swab unit is connected to the body, a second explosives detecting reagent, and a second reagent holder and dispenser operatively connected to the body, the second reagent holder and dispenser containing the second explosives detecting reagent and positioned to deliver the second explosives detecting reagent to the lateral flow membrane swab unit when the lateral flow membrane swab unit is connected to the body.

  18. Sensitivity to friction for primary explosives.

    Science.gov (United States)

    Matyáš, Robert; Šelešovský, Jakub; Musil, Tomáš

    2012-04-30

    The sensitivity to friction for a selection of primary explosives has been studied using a small BAM friction apparatus. The probit analysis was used for the construction of a sensitivity curve for each primary explosive tested. Two groups of primary explosives were chosen for measurement (a) the most commonly used industrially produced primary explosives (e.g. lead azide, tetrazene, dinol, lead styphnate) and (b) the most produced improvised primary explosives (e.g. triacetone triperoxide, hexamethylenetriperoxide diamine, mercury fulminate, acetylides of heavy metals). A knowledge of friction sensitivity is very important for determining manipulation safety for primary explosives. All the primary explosives tested were carefully characterised (synthesis procedure, shape and size of crystals). The sensitivity curves obtained represent a unique set of data, which cannot be found anywhere else in the available literature. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Applying NASA's explosive seam welding

    Science.gov (United States)

    Bement, Laurence J.

    1991-01-01

    The status of an explosive seam welding process, which was developed and evaluated for a wide range of metal joining opportunities, is summarized. The process employs very small quantities of explosive in a ribbon configuration to accelerate a long-length, narrow area of sheet stock into a high-velocity, angular impact against a second sheet. At impact, the oxide films of both surface are broken up and ejected by the closing angle to allow atoms to bond through the sharing of valence electrons. This cold-working process produces joints having parent metal properties, allowing a variety of joints to be fabricated that achieve full strength of the metals employed. Successful joining was accomplished in all aluminum alloys, a wide variety of iron and steel alloys, copper, brass, titanium, tantalum, zirconium, niobium, telerium, and columbium. Safety issues were addressed and are as manageable as many currently accepted joining processes.

  20. Explosives detection system and method

    Science.gov (United States)

    Reber, Edward L.; Jewell, James K.; Rohde, Kenneth W.; Seabury, Edward H.; Blackwood, Larry G.; Edwards, Andrew J.; Derr, Kurt W.

    2007-12-11

    A method of detecting explosives in a vehicle includes providing a first rack on one side of the vehicle, the rack including a neutron generator and a plurality of gamma ray detectors; providing a second rack on another side of the vehicle, the second rack including a neutron generator and a plurality of gamma ray detectors; providing a control system, remote from the first and second racks, coupled to the neutron generators and gamma ray detectors; using the control system, causing the neutron generators to generate neutrons; and performing gamma ray spectroscopy on spectra read by the gamma ray detectors to look for a signature indicative of presence of an explosive. Various apparatus and other methods are also provided.

  1. RANCHERO explosive pulsed power experiments

    CERN Document Server

    Goforth, J H; Armijo, E V; Atchison, W L; Bartos, Yu; Clark, D A; Day, R D; Deninger, W J; Faehl, R J; Fowler, C M; García, F P; García, O F; Herrera, D H; Herrera, T J; Keinigs, R K; King, J C; Lindemuth, I R; López, E; Martínez, E C; Martínez, D; McGuire, J A; Morgan, D; Oona, H; Oro, D M; Parker, J V; Randolph, R B; Reinovsky, R E; Rodríguez, G; Stokes, J L; Sena, F C; Tabaka, L J; Tasker, D G; Taylor, A J; Torres, D T; Anderson, H D; Broste, W B; Johnson, J B; Kirbie, H C

    1999-01-01

    The authors are developing the RANCHERO high explosive pulsed power (HEPP) system to power cylindrically imploding solid-density liners for hydrodynamics experiments. Their near-term goal is to conduct experiments in the regime pertinent to the Atlas capacitor bank. That is, they will attempt to implode liners of ~50 g mass at velocities approaching 15 km/sec. The basic building block of the HEPP system is a coaxial generator with a 304.8 mm diameter stator, and an initial armature diameter of 152 mm. The armature is expanded by a high explosive (HE) charge detonated simultaneously along its axis. The authors have reported a variety of experiments conducted with generator modules 43 cm long and have presented an initial design for hydrodynamic liner experiments. In this paper, they give a synopsis of their first system test, and a status report on the development of a generator module that is 1.4 m long. (6 refs).

  2. Determination of Nanogram Microparticles from Explosives after Real Open-Air Explosions by Confocal Raman Microscopy.

    Science.gov (United States)

    Zapata, Félix; García-Ruiz, Carmen

    2016-07-05

    Explosives are increasingly being used for terrorist attacks to cause devastating explosions. The detection of their postblast residues after an explosion is a high challenge, which has been barely investigated, particularly using spectroscopic techniques. In this research, a novel methodology using confocal Raman microscopy has been developed for the analysis of postblast residues from 10 open-air explosions caused by 10 different explosives (TNT, RDX, PETN, TATP, HMTD, dynamite, black powder, ANFO, chloratite, and ammonal) commonly used in improvised explosive devices. The methodology for the determination of postblast particles from explosives consisted of examining the samples surfaces with both the naked eye, first, and microscopically (10× and 50×), immediately afterward; and finally, analyzing the selected residues by confocal Raman spectroscopy in order to identify the postblast particles from explosives. Interestingly, confocal Raman microscopy has demonstrated to be highly suitable to rapidly, selectively, and noninvasively analyze postblast microscopic particles from explosives up to the nanogram range.

  3. Development of numerical framework to study microstructural effects on shock initiation in heterogeneous energetic materials

    Science.gov (United States)

    Schmidt, Martin; Rai, Nirmal; Udaykumar, H. S.

    2015-06-01

    Heterogeneous energetic materials like plastic bonded explosives (PBX) have very detailed and non-uniform microstructure. The heterogeneity is mainly because of presence of HMX crystals embedded in a polymer binder matrix. Also, manufacturing defects often creates pores and cracks in the material. Shock interaction with these heterogeneities leads to local heated regions known as hot spots. It is widely accepted that these hot spots are predominantly the cause of triggering reaction and eventually ignition in these energetic materials. There are various physical phenomenon through which hot spot can be created such as pore collapse, inter-granular friction in HMX crystals, shock heating of HMX crystals and binder etc. Hence, microstructural heterogeneity can play a vital role for shock initiation in PBX. In the current work, a general framework has been established for performing mesoscale simulations on heterogeneous energetic material. In order to get an accurate representation of the microstructure, image processing algorithms have been employed on XCMT images of PBX microstructure. The image processing framework has been built up with massively parallel Eulerian code, SCIMITAR3D. Shock simulation on PBX microstructures has been performed and the effect of microstructure geometry has been studied for different shock strengths case. The simulation results have been shown to resolve hot spots created due to various heterogeneities present in the microstructure.

  4. EXPLOSION RISK ASSESSMENTS FOR FACILITIES

    Directory of Open Access Journals (Sweden)

    Martin KULICH

    2015-12-01

    Full Text Available In the first part of the article we discuss the possibilities and analytical tools that can deal with the classification of space into zones with danger of explosion for devices with the presence of compressed flammable gases. Then we continue with specifications of possibilities for practical utilization linked to variables such as ventilation degree, hypothetical volume etc., including the examples. At the end we also give a brief overview of software for modelling gas leak, including examples of an outcome.

  5. Trace Explosives Detection by Photoluminescence

    OpenAIRE

    2004-01-01

    Some field tests in counter-terrorism efforts to detect explosive traces employ chemistries that yield colored products. We have examined a test kit of this kind, ETKPlus, based on widely used chemistries and employed extensively by the Israel Police. Our investigation focuses on the prospect of gaining sensitivity by replacing the normal colorimetric modality with photoluminescence detection, which, to our knowledge, has not been explored to date. We find two or more orders of magnitude sens...

  6. LX-10 Explosive Damage Studies

    Science.gov (United States)

    2015-03-03

    Suite NAWCWD TM 8757 6 where P = System pressure Vs = System volume n = Covolume we = Weight of explosive burned F = Impetus, f...simultaneously ignited and regress uniformly, and the regression rate depends only on pressure and propellant temperature. 2. Heat losses from the bomb are...and fired in a manometric closed vessel. The pressure -time history was recorded, and an analysis of the data was performed to evaluate both the

  7. Shell and explosive hydrogen burning

    CERN Document Server

    Boeltzig, A; Cavanna, F; Cristallo, S; Davinson, T; Depalo, R; deBoer, R J; Di Leva, A; Ferraro, F; Imbriani, G; Marigo, P; Terrasi, F; Wiescher, M

    2016-01-01

    The nucleosynthesis of light elements, from helium up to silicon, mainly occurs in Red Giant and Asymptotic Giant Branch stars and Novae. The relative abundances of the synthesized nuclides critically depend on the rates of the nuclear processes involved, often through non-trivial reaction chains, combined with complex mixing mechanisms. In this review, we summarize the contributions made by LUNA experiments in furthering our understanding of nuclear reaction rates necessary for modeling nucleosynthesis in AGB stars and Novae explosions.

  8. Synthesis Craft of HMX from 1,5-Methylene-3,7-dintrio-1,3,5,7-tetraazacyclooctane%DPT制备HMX工艺研究

    Institute of Scientific and Technical Information of China (English)

    李全良; 陈军; 王建龙

    2007-01-01

    以乌洛托品为起始原料,合成了中间体3,7-二硝基-1,3,5,7-四氮杂双环[3,3,1]壬烷(DPT),然后以氧化镁、硝酸铵、硝酸为硝解体系,硝解DPT制备出HMX.结果表明:在25 ℃的条件下,反应30 min,收率达60.1%,工艺条件温和,易于控制,反应废液容易处理.

  9. Fuze for explosive magnetohydrodynamic generator

    Energy Technology Data Exchange (ETDEWEB)

    Webb, G.

    1976-12-23

    An apparatus is examined by which high explosive charges are propelled into and detonated at the center of an MHD-X generator. The high explosive charge units are engaged and propelled by a reciprocating ram device. Detonating in each instance is achieved by striking with a firing pin a detonator charge that is in register with a booster charge, the booster charge being in detonating communication with the high explosive charge. Various safety requirements are satisfied by a spring loaded slider operating in a channel transverse and adjacent to the booster charge. The slide retains the detonator charge out of register with the booster charge until a safety pin that holds the slider in place is pulled by a lanyard attached between the reciprocating ram and the safety pin. Removal of the safety pin permits the detonator charge to slide into alignment with the booster charge. Firing pin actuation is initiated by the slider at the instant the detonator charge and the booster charge come into register.

  10. Thermodynamic States in Explosion Fields

    Energy Technology Data Exchange (ETDEWEB)

    Kuhl, A L

    2010-03-12

    We investigate the thermodynamic states occurring in explosion fields from condensed explosive charges. These states are often modeled with a Jones-Wilkins-Lee (JWL) function. However, the JWL function is not a Fundamental Equation of Thermodynamics, and therefore cannot give a complete specification of such states. We use the Cheetah code of Fried to study the loci of states of the expanded detonation products gases from C-4 charges, and their combustion products air. In the Le Chatelier Plane of specific-internal-energy versus temperature, these loci are fit with a Quadratic Model function u(T), which has been shown to be valid for T < 3,000 K and p < 1k-bar. This model is used to derive a Fundamental Equation u(v,s) for C-4. Given u(v,s), one can use Maxwell's Relations to derive all other thermodynamic functions, such as temperature: T(v,s), pressure: p(v,s), enthalpy: h(v,s), Gibbs free energy: g(v,s) and Helmholz free energy: f(v,s); these loci are displayed in figures for C-4. Such complete equations of state are needed for numerical simulations of blast waves from explosive charges, and their reflections from surfaces.

  11. Nuclear Explosions 1945-1998

    Energy Technology Data Exchange (ETDEWEB)

    Bergkvist, Nils-Olov; Ferm, Ragnhild

    2000-07-01

    The main part of this report is a list of nuclear explosions conducted by the United States, the Soviet Union, the United Kingdom, France, China, India and Pakistan in 1945-98. The list includes all known nuclear test explosions and is compiled from a variety of sources including officially published information from the USA, Russia and France. The details given for each explosion (date, origin time, location, yield, type, etc.) are often compiled from more than one source because the individual sources do not give complete information. The report includes a short background to nuclear testing and provides brief information on the Comprehensive Nuclear-Test-Ban Treaty and the verification regime now being established to verify compliance with the treaty. It also summarizes nuclear testing country by country. The list should be used with some caution because its compilation from a variety of sources means that some of the data could be incorrect. This report is the result of cooperation between the Defence Research Establishment (FOA) and the Stockholm International Peace Research Institute (SIPRI)

  12. Overview on Theoretical Prediction of 3,6-Bis-(3,5-dinitro-1,2,4-triazolyl)-1,2,4,5-tetrazine as a High Performance Explosive%高性能炸药3,6-双-(3,5-二硝基-1,2,4-三唑基)-1,2,4,5-四嗪的理论估算概述

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This work presents various aspect of properties of 3,6-bis-(3,5-dinitro-1,2,4-triazolyl)-1,2,4,5-triazine or BDTT,that has not been synthesized yet,as a novel energetic heterocyclic compound.Crystal density,condensed phase heat of formation,detonation temperature,impact sensitivity,shock sensitivity based on small-scale gap test,adiabatic exponent and heat of detonation as well as detonation pressure and velocity that are important properties for explosive users are investigated.It is shown that sensitivity of BDTT as a high performance explosive is less than HMX and RDX.Moreover,high oxygen content of BDTT can introduce it as suitable oxidizer to use in solid propellants.

  13. Totally confined explosive welding. [apparatus to reduce noise level and protect personnel during explosive bonding

    Science.gov (United States)

    Bement, L. J. (Inventor)

    1974-01-01

    A method and associated apparatus for confining the undesirable by-products and limiting noise of explosive welding are discussed. The apparatus consists fo a simple enclosure into which the explosive is placed and within which the explosion occurs. The shape of the enclosure, the placement of the explosive, and the manner in which the enclosure is placed upon the material to be welded determine the force of the explosion transmitted to the proposed bond area. The explosion is totally confined within the enclosure thus reducing the noise level and preventing debris from being strewn about to contaminate the weld area or create personnel hazards.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-08-01

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

  15. Thermal-mechanical-chemical responses of polymer-bonded explosives using a mesoscopic reactive model under impact loading.

    Science.gov (United States)

    Wang, XinJie; Wu, YanQing; Huang, FengLei

    2017-01-05

    A mesoscopic framework is developed to quantify the thermal-mechanical-chemical responses of polymer-bonded explosive (PBX) samples under impact loading. A mesoscopic reactive model is developed for the cyclotetramethylenetetranitramine (HMX) crystal, which incorporates nonlinear elasticity, crystal plasticity, and temperature-dependent chemical reaction. The proposed model was implemented in the finite element code ABAQUS by the user subroutine VUMAT. A series of three-dimensional mesoscale models were constructed and calculated under low-strength impact loading scenarios from 100m/s to 600m/s where only the first wave transit is studied. Crystal anisotropy and microstructural heterogeneity are responsible for the nonuniform stress field and fluctuations of the stress wave front. At a critical impact velocity (≥300m/s), a chemical reaction is triggered because the temperature contributed by the volumetric and plastic works is sufficiently high. Physical quantities, including stress, temperature, and extent of reaction, are homogenized from those across the microstructure at the mesoscale to compare with macroscale measurements, which will advance the continuum-level models. The framework presented in this study has important implications in understanding hot spot ignition processes and improving predictive capabilities in energetic materials.

  16. Thermal explosion in oscillating ambient conditions

    Science.gov (United States)

    Novozhilov, Vasily

    2016-07-01

    Thermal explosion problem for a medium with oscillating ambient temperature at its boundaries is considered. This is a new problem in thermal explosion theory, not previously considered in a distributed system formulation, but important for combustion and fire science. It describes autoignition of wide range of fires (such as but not limited to piles of biosolids and other organic matter; storages of munitions, explosives, propellants) subjected to temperature variations, such as seasonal or day/night variation. The problem is considered in formulation adopted in classical studies of thermal explosion. Critical conditions are determined by frequency and amplitude of ambient temperature oscillations, as well as by a number of other parameters. Effects of all the parameters on critical conditions are quantified. Results are presented for the case of planar symmetry. Development of thermal explosion in time is also considered, and a new type of unsteady thermal explosion development is discovered where thermal runaway occurs after several periods of temperature oscillations within the medium.

  17. Numerical computations of explosions in gases

    Science.gov (United States)

    Chushkin, P. I.; Shurshalov, L. V.

    The development and the present-day state of the problem on numerical computations of explosions in gases are reviewed. In the first part, different one-dimensional cases are discussed: point explosion with counterpressure, blast-like expansion of volumes filled with a compressed hot gas, blast of charges of condensed explosive, explosion processes in real high-temperature air, in combustible detonating media and under action of other physical-chemical factors. In the second part devoted to two-dimensional flows, we consider explosion in the non-homogeneous atmosphere, blast of asymmetric charges, detonation in gas, explosion modelling of some cosmic phenomena (solar flares, the Tunguska meteorite). The survey includes about 110 works beginning with the first publications on the subject.

  18. APPLICATION OF EXPLOSIVE ENERGY IN METALWORKING

    Directory of Open Access Journals (Sweden)

    Vječislav Bohanek

    2013-07-01

    Full Text Available When an explosive charge is detonate, considerable amount of energy in a very short period of time is released. Energy, released in this way, is used for performing various kinds of useful work. Most explosives are consumed to obtain mineral raw materials in the mining industry and for various excavations in the construction industry. One of the specific areas of application explosive energy is an area of explosive metalworking. Using energy of explosive metal is welded, formed, cuts, harden etc. This paper presents an overview of the existing explosive metalworking methods. Methods are explained and comparative advantages in comparison to conventional metalworking methods are given (the paper is published in Croatian.

  19. LOW AMPLITUDE SINGLE AND MULTIPLE SHOCK INITIATION EXPERIMENTS AND MODELING OF LX-04

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-06-27

    Shock initiation experiments were performed on the plastic bonded explosive (PBX) LX-04 (85% HMX, 15% Viton binder) using single and multiple low amplitude shocks to obtain pressure history data for use in Ignition and Growth reactive flow modeling parameterization. A 100 mm diameter propellant driven gas gun was utilized to initiate the LX-04 explosive charges containing manganin piezoresistive pressure gauge packages placed between explosive discs. In the single shock experiments, the run distances to detonation at three shock pressures showed agreement with previously published data above 3 GPa. Even longer run distances to detonation were measured using 80 mm long by 145 mm diameter LX-04 charges impacted by low velocity projectiles from a 155 mm diameter gun. The minimum shock pressure required to cause low levels of exothermic reaction were determined for these large LX-04 charge dimensions. Multiple shocks were generated as double shocks by using a flyer plate with two materials and as reflected shocks by placing a high impedance material at the rear of the explosive charge. In both cases, the first shock pressure was not high enough to cause detonation of LX-04, and the second shock pressure, which would have been sufficient to cause detonation if generated by a single shock, failed to cause detonation. Thus LX-04 exhibited shock desensitization over a range of 0.6 to 1.4 GPa. The higher shock pressure LX-04 model was extended to accurately simulate these lower pressure and multiple shock gauge records. The shock desensitization effects observed with multiple shock compressions were partially accounted for in the model by using a critical compression corresponding to a shock pressure of 1.2 GPa. This shock desensitization effect occurs at higher pressures than those of other HMX-based PBX's containing higher HMX percentages.

  20. Elastic constants of B-HMX and tantalum, equations of state of supercritical fluids and fluid mixtures and thermal transport determinations

    Energy Technology Data Exchange (ETDEWEB)

    Zaug, J M

    1998-08-21

    Ultrasonic sound speed measurements via Impulsive Stimulated Light Scattering (ISLS) were made in single crystals of b-HMX and tantalum over an extended range of temperatures. Elastic constants are consequently determined for b-HMX. Sound speeds are calculated for tantalum, from known elastic constants, and compare favorably with the results presented here. ISLS time-domain fits of tantalum records allowed for thermal diffusion determinations and, correspondingly, thermal conductivity. Measurements of the speed of sound and of the thermal diffusivities of fluid oxygen up to pressures of 13 GPa and at several temperatures are presented. Between 0.1 and 13 GPa the fluid's density increases by a factor of three. Thermal diffusivities rise slowly over this range, and are substantially smaller than those previously measured for the solid b-phase. Additional sound speed measurements were made along the 250 C isotherm in a 1:1 molar ratio mixture of liquid oxygen and nitrogen. These experiments demonstrate the versatility and potential application of a new laboratory within the U. S. DOD and DOE complex. 1

  1. Momentum transfer in indirect explosive drive

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, J.E.; Warnes, R.H. [Los Alamos National Lab., NM (United States); Cherry, C.R.; Cherry, C.R. Jr.; Fischer, S.H. [Sandia National Labs., Albuquerque, NM (United States)

    1996-07-01

    Material which is not in direct contact with detonating explosives may still be driven by the explosion through impact by driven material or by attachment to driven material. In such circumstances the assumption of inelastic collision permits estimation of the final velocity of an assemblage. Examples of the utility of this assumption are demonstrated through use of Gurney equations. The inelastic collision calculation may also be used for metal parts which are driven by explosives partially covering the metal. We offer a new discounting angle to account for side energy losses from laterally unconfined explosive charges in cases where the detonation wave travels parallel to the surface which is driven.

  2. Method and apparatus for detecting explosives

    Science.gov (United States)

    Moore, David Steven [Santa Fe, NM

    2011-05-10

    A method and apparatus is provided for detecting explosives by thermal imaging. The explosive material is subjected to a high energy wave which can be either a sound wave or an electromagnetic wave which will initiate a chemical reaction in the explosive material which chemical reaction will produce heat. The heat is then sensed by a thermal imaging device which will provide a signal to a computing device which will alert a user of the apparatus to the possibility of an explosive device being present.

  3. Explosive Field Visualization Based on Image Fusion

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wen-yao; JIANG Ling-shuang

    2009-01-01

    m the composite sequence. Experimental results show that the new images integrate the advantages of sources, effectively improve the visualization, and disclose more information about explosive field.

  4. High Explosives Research and Development (HERD) Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The purpose is to provide high explosive formulation, chemical analysis, safety and performance testing, processing, X-ray, quality control and loading support for...

  5. 27 CFR 555.181 - Reporting of plastic explosives.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Reporting of plastic..., FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of Plastic Explosives § 555.181 Reporting of plastic explosives. All persons, other than an agency of the United...

  6. 27 CFR 70.445 - Commerce in explosives.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Commerce in explosives. 70... Cartridges, and Explosives § 70.445 Commerce in explosives. Part 55 of title 27 CFR contains the regulations..., explosives, (b) Permits for users who buy or transport explosives in interstate or foreign commerce,...

  7. 29 CFR 1926.902 - Surface transportation of explosives.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Surface transportation of explosives. 1926.902 Section 1926... Explosives § 1926.902 Surface transportation of explosives. (a) Transportation of explosives shall meet the... Carriers. (b) Motor vehicles or conveyances transporting explosives shall only be driven by, and be in the...

  8. 29 CFR 1926.903 - Underground transportation of explosives.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Underground transportation of explosives. 1926.903 Section... Explosives § 1926.903 Underground transportation of explosives. (a) All explosives or blasting agents in... explosives or blasting agents taken to an underground loading area shall not exceed the amount estimated to...

  9. 27 CFR 555.63 - Explosives magazine changes.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Explosives magazine..., FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Licenses and Permits § 555.63 Explosives magazine changes. (a) General. (1) The requirements of this section are applicable...

  10. 30 CFR 75.1310 - Explosives and blasting equipment.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Explosives and blasting equipment. 75.1310... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1310 Explosives and blasting equipment. (a) Only permissible explosives, approved sheathed explosive units,...

  11. Impact of glycerin and lignosulfonate on biodegradation of high explosives in soil

    Science.gov (United States)

    Won, Jongho; Borden, Robert C.

    2016-11-01

    Soil microcosms were constructed and monitored to evaluate the impact of substrate addition and transient aerobic and anaerobic conditions on TNT, RDX and HMX biodegradation in grenade range soils. While TNT was rapidly biodegraded under both aerobic and anaerobic conditions with and without organic substrate, substantial biodegradation of RDX, HMX, and RDX daughter products was not observed under aerobic conditions. However, RDX and HMX were significantly biodegraded under anaerobic conditions, without accumulation of TNT or RDX daughter products (2-ADNT, 4-ADNT, MNX, DNX, and TNX). In separate microcosms containing grenade range soil, glycerin and lignosulfonate addition enhanced oxygen consumption, increasing the consumption rate > 200% compared to untreated soils. Mathematical model simulations indicate that oxygen consumption rates of 5 to 20 g/m3/d can be achieved with reasonable amendment loading rates. These results indicate that glycerin and lignosulfonate can be potentially used to stimulate RDX and HMX biodegradation by increasing oxygen consumption rates in soil.

  12. General phenomenology of underground nuclear explosions; Phenomenologie generale des explosions nucleaires souterraines

    Energy Technology Data Exchange (ETDEWEB)

    Derlich, S.; Supiot, F. [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    An essentially qualitatively description is given of the phenomena related to underground nuclear explosions (explosion of a single unit, of several units in line, and simultaneous explosions). In the first chapter are described the phenomena which are common to contained explosions and to explosions forming craters (formation and propagation of a shock-wave causing the vaporization, the fusion and the fracturing of the medium). The second chapter describes the phenomena related to contained explosions (formation of a cavity with a chimney). The third chapter is devoted to the phenomenology of test explosions which form a crater; it describes in particular the mechanism of formation and the different types of craters as a function of the depth of the explosion and of the nature of the ground. The aerial phenomena connected with explosions which form a crater: shock wave in the air and focussing at a large distance, and dust clouds, are also dealt with. (authors) [French] On donne une description essentiellement qualitative des phenomenes lies aux explosions nucleaires souterraines (explosion d'un seul engin, d'engins en ligne et explosions simultanees). Dans un premier chapitre sont decrits les phenomenes communs aux explosions contenues et aux explosions formant un cratere (formation et propagation d'une onde de choc provoquant la vaporisation, la fusion et la fracturation du milieu). Le deuxieme chapitre decrit les phenomenes lies aux tirs contenus (formation d'une cavite et d'une cheminee). Le troisieme chapitre est consacre a la phenomenologie des tirs formant un cratere et decrit notamment le mecanisme de formation et les differents types de crateres en fonction de la profondeur d'explosion et de la nature du terrain. Les phenomenes aeriens lies aux explosions formant un cratere: onde de pression aerienne et focalisation a grande distance, nuages de poussieres, sont egalement abordes. (auteurs)

  13. Static Charge Development on Explosives .

    Directory of Open Access Journals (Sweden)

    K. Raha

    1991-01-01

    Full Text Available Static charge development character of some of the important explosive crystals have been predicted on the basis of their crystal class and symmetry. Among the important mechanism of charge development, the piezoelectric and pyroelectric characters have been considered. Ammonium trinitrate, ammonium nitrate, m-dinitro-benzene, trinitro-toluene, styphnic acid, beeta-lead styphnate, 4,4'dinitro-dipheny1, a-hexamethylenetetranitramine, nitroguanidine, picric acid, dimethylnitramine, a-lead azide and beeta-lead azide are pyroelectric in nature, whereas pentaerythritol tetranitrate, picryliodide, hexamethylenetranitramine, tetranitromethane and trinitroethane are piezoelectric in nature.

  14. The gas dynamics of explosions

    CERN Document Server

    Lee,\tJohn H S

    2016-01-01

    Explosions, and the non-steady shock propagation associated with them, continue to interest researchers working in different fields of physics and engineering (such as astrophysics and fusion). Based on the author's course in shock dynamics, this book describes the various analytical methods developed to determine non-steady shock propagation. These methods offer a simple alternative to the direct numerical integration of the Euler equations and offer a better insight into the physics of the problem. Professor Lee presents the subject systematically and in a style that is accessible to graduate students and researchers working in shock dynamics, combustion, high-speed aerodynamics, propulsion and related topics.

  15. Growth and defects of explosives crystals

    Science.gov (United States)

    Cady, H. H.

    Large single crystals of PETN, RDX, and TNT can be grown easily from evaporating ethyl acetate solutions. The crystals all share a similar type of defect that may not be commonly recognized. The defect generates conical faces, ideally mosaic crystals, and may account for the 'polymorphs' of TNT and detonator grades of PETN. TATB crystals manufactured by the amination of trichlorotrinitrobenzene in dry toluene entrain two forms of ammonium chloride. One of these forms causes 'worm holes' in the TATB crystals that may be the reason for its unusually low failure diameters. Strained HMX crystals form mechanical twins that can spontaneously revert back to the untwinned form when the straining force is removed. Large strains or temperatures above 100 C lock in the mechanical twins.

  16. A structured approach to forensic study of explosions: The TNO Inverse Explosion Analysis tool

    NARCIS (Netherlands)

    Voort, M.M. van der; Wees, R.M.M. van; Brouwer, S.D.; Jagt-Deutekom, M.J. van der; Verreault, J.

    2015-01-01

    Forensic analysis of explosions consists of determining the point of origin, the explosive substance involved, and the charge mass. Within the EU FP7 project Hyperion, TNO developed the Inverse Explosion Analysis (TNO-IEA) tool to estimate the charge mass and point of origin based on observed damage

  17. 75 FR 1085 - Commerce in Explosives; List of Explosive Materials (2009R-18T)

    Science.gov (United States)

    2010-01-08

    ... [Federal Register Volume 75, Number 5 (Friday, January 8, 2010)] [Notices] [Pages 1085-1087] [FR Doc No: 2010-45] DEPARTMENT OF JUSTICE Bureau of Alcohol, Tobacco, Firearms and Explosives [Docket No. ATF 34N] Commerce in Explosives; List of Explosive Materials (2009R-18T) AGENCY: Bureau of...

  18. Processing Benefits of Resonance Acoustic Mixing on High Performance Propellants and Explosives

    Science.gov (United States)

    2012-02-01

    Initial Energetic Evaluation File: NAVAIR Brief 12 • Selected Energetics – Polymers: GAP, PGN, PNO , BN-7 – Plasticizers: BTTN, TMETN, TEGDN, BuNena...BTTN-CL20 202 204 2 PGN-BTTN-RDX 191 191 0 PGN-BTTN-HMX 183 186 3 PGN-BTTN-CL20 189 189 0 PNO -BTTN-RDX 184 189 5 PNO -BTTN-HMX 179 175 4 PNO -BTTN

  19. 主成分分析法用于单质炸药爆轰性能评估的研究%Evaluation of Explosive Detonation Performance by Principal Component Analysis (PCA)

    Institute of Scientific and Technical Information of China (English)

    汪飞; 何中其; 陈网桦

    2013-01-01

    炸药的爆轰性能是评价炸药综合毁伤能力的重要指标,是进行炸药装药设计、开发和优选工作的前提.为实现对炸药的综合爆轰性能进行合理评估,必须对炸药的5大爆轰参数(爆热、爆速、爆压、爆容、爆温)进行综合考虑和计算.尝试应用针对多元统计技术的主成分分析法,对TNT、RDX、HMX等常用单质炸药的所有爆轰参数开展了分析与评估.结果表明,炸药各爆轰参数的信息重叠度较大,主成分的贡献率可达到90.1%,在爆轰性能综合评估中可以只参考爆热和爆速.最后利用第一和第二主成分的贡献率为权数,构造了炸药爆轰性能综合评估函数;对常用炸药的强弱排序也与各自威力经验值相符,评估有效.%The detonation performance is not only an important indicator of the comprehensive evaluation for explosive damage ability, but also the premise for the explosive design, development and optimization work. To achieve a reasonable assessment of the explosive detonation performance, five detonation parameters, such as the heat of explosion, velocity of detonation, pressure of detonation, volume of explosion, temperature of explosion, require comprehensive consideration and calculation. Principal component analysis based on multivariate statistical techniques is attempted to apply to analyzing and evaluating detonation parameters of TNT, RDX, HMX and other ordinary explosives. The results showed that the overlap ratio of the detonation parameters is high with the contribution rate of the main ingredients to be up to 90. 1%. The explosion heat and the detonation velocity can only be referred in the comprehensive assessment of the detonation performance. Finally a comprehensive evaluation function with the contribution rate of the first and second principal components is constructed. It can be seen that the sorting of detonation performance of common explosives is consistent with their empirical power

  20. Geotechnical Aspects of Explosive Compaction

    Directory of Open Access Journals (Sweden)

    Mahdi Shakeran

    2016-01-01

    Full Text Available Explosive Compaction (EC is the ground modification technique whereby the energy released from setting off explosives in subsoil inducing artificial earthquake effects, which compact the soil layers. The efficiency of EC predominantly depends on the soil profile, grain size distribution, initial status, and the intensity of energy applied to the soil. In this paper, in order to investigate the geotechnical aspects, which play an important role in performance of EC, a database has been compiled from thirteen-field tests or construction sites around the world, where EC has been successfully applied for modifying soil. This research focuses on evaluation of grain size distribution and initial stability status of deposits besides changes of soil penetration resistance due to EC. Results indicated suitable EC performance for unstable and liquefiable deposits having particle sizes ranging from gravel to silty sand with less than 40% silt content and less than 10% clay content. However, EC is most effective in fine-to-medium sands with a fine content less than 5% and hydraulically deposited with initial relative density ranging from 30% to 60%. Moreover, it has been observed that EC can be an effective method to improve the density, stability, and resistance of the target soils.

  1. Explosions inside Ejecta and Most Luminous Supernovae

    CERN Document Server

    Blinnikov, S I

    2008-01-01

    The extremely luminous supernova SN2006gy is explained in the same way as other SNIIn events: light is produced by a radiative shock propagating in a dense circumstellar envelope formed by a previous weak explosion. The problems in the theory and observations of multiple-explosion SNe IIn are briefly reviewed.

  2. Simulation of explosive welding with ANFO mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Mousavi, A.A. Akbari; Burley, Stephen J.; Al-Hassani, S.T.S. [Department of Mechanical, Aerospace and Manufacturing Engineering, UMIST, PO Box 88, Manchester M60 1QD (United Kingdom); Byers Brown, W. [Mass Action Research Consultancy, Devonshire House, 14 Corbar Road, Buxton, SK17 6RQ (United Kingdom)

    2004-06-01

    The work described here arose from a study into explosive welding. As part of that study, the impact velocity of stainless steel and titanium plates to grazing detonation of ANFO/perlite, the velocity of detonation were measured. Computer simulation required a new model which copes with an equation of state of low explosives. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

  3. 77 FR 55108 - Explosive Siting Requirements

    Science.gov (United States)

    2012-09-07

    ... trinitrotoluene (TNT) equivalents of less than or equal to 450 pounds. Although decreased, the revised separation... required separation distances for division 1.1 explosives and liquid propellants with TNT equivalents that... separation from a given net explosive weight (NEW) is one percent, which is an equivalent level of safety...

  4. Fire and explosion hazards of oil shale

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    The US Bureau of Mines publication presents the results of investigations into the fire and explosion hazards of oil shale rocks and dust. Three areas have been examined: the explosibility and ignitability of oil shale dust clouds, the fire hazards of oil shale dust layers on hot surfaces, and the ignitability and extinguishment of oil shale rubble piles. 10 refs., 54 figs., 29 tabs.

  5. Sensitivity to friction for primary explosives

    Energy Technology Data Exchange (ETDEWEB)

    Matyas, Robert, E-mail: robert.matyas@upce.cz [Institute of Energetic Materials, Faculty of Chemical Technology, University of Pardubice, Pardubice 532 10 (Czech Republic); Selesovsky, Jakub; Musil, Tomas [Institute of Energetic Materials, Faculty of Chemical Technology, University of Pardubice, Pardubice 532 10 (Czech Republic)

    2012-04-30

    Highlights: Black-Right-Pointing-Pointer The friction sensitivity of 14 samples of primary explosives was determined. Black-Right-Pointing-Pointer The same apparatus (small scale BAM) and the same method (probit analysis) was used. Black-Right-Pointing-Pointer The crystal shapes and sizes were documented with microscopy. Black-Right-Pointing-Pointer Almost all samples are less sensitive than lead azide, which is commercially used. Black-Right-Pointing-Pointer The organic peroxides (TATP, DADP, HMTD) are not as sensitive as often reported. - Abstract: The sensitivity to friction for a selection of primary explosives has been studied using a small BAM friction apparatus. The probit analysis was used for the construction of a sensitivity curve for each primary explosive tested. Two groups of primary explosives were chosen for measurement (a) the most commonly used industrially produced primary explosives (e.g. lead azide, tetrazene, dinol, lead styphnate) and (b) the most produced improvised primary explosives (e.g. triacetone triperoxide, hexamethylenetriperoxide diamine, mercury fulminate, acetylides of heavy metals). A knowledge of friction sensitivity is very important for determining manipulation safety for primary explosives. All the primary explosives tested were carefully characterised (synthesis procedure, shape and size of crystals). The sensitivity curves obtained represent a unique set of data, which cannot be found anywhere else in the available literature.

  6. Gas explosion prediction using CFD models

    Energy Technology Data Exchange (ETDEWEB)

    Niemann-Delius, C.; Okafor, E. [RWTH Aachen Univ. (Germany); Buhrow, C. [TU Bergakademie Freiberg Univ. (Germany)

    2006-07-15

    A number of CFD models are currently available to model gaseous explosions in complex geometries. Some of these tools allow the representation of complex environments within hydrocarbon production plants. In certain explosion scenarios, a correction is usually made for the presence of buildings and other complexities by using crude approximations to obtain realistic estimates of explosion behaviour as can be found when predicting the strength of blast waves resulting from initial explosions. With the advance of computational technology, and greater availability of computing power, computational fluid dynamics (CFD) tools are becoming increasingly available for solving such a wide range of explosion problems. A CFD-based explosion code - FLACS can, for instance, be confidently used to understand the impact of blast overpressures in a plant environment consisting of obstacles such as buildings, structures, and pipes. With its porosity concept representing geometry details smaller than the grid, FLACS can represent geometry well, even when using coarse grid resolutions. The performance of FLACS has been evaluated using a wide range of field data. In the present paper, the concept of computational fluid dynamics (CFD) and its application to gas explosion prediction is presented. Furthermore, the predictive capabilities of CFD-based gaseous explosion simulators are demonstrated using FLACS. Details about the FLACS-code, some extensions made to FLACS, model validation exercises, application, and some results from blast load prediction within an industrial facility are presented. (orig.)

  7. Fire and explosion hazards of oil shale

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    The US Bureau of Mines publication presents the results of investigations into the fire and explosion hazards of oil shale rocks and dust. Three areas have been examined: the explosibility and ignitability of oil shale dust clouds, the fire hazards of oil shale dust layers on hot surfaces, and the ignitability and extinguishment of oil shale rubble piles. 10 refs., 54 figs., 29 tabs.

  8. Summary of European directives for explosion safety

    NARCIS (Netherlands)

    Versloot, N.H.A.; Klein, A.J.J.; Maaijer, M. de

    2008-01-01

    On July 1, 2003 a transitional period has ended and two European directives became fully active: • Directive 1999/92/EC • Directive 94/9/EC These directives have an impact on companies with an explosion hazard (gas, vapor, mist, or dust explosions) and on manufacturers of equipment intended to be

  9. Explosion risks and consequences for tunnels

    NARCIS (Netherlands)

    Weerheijm, J.; Berg, A.C. van den

    2014-01-01

    Tunnel accidents with transports of dangerous goods may lead to explosions. Risk assessment for these accidents is complicated because of the low probability and the unknown, but disastrous effects expected. Especially the lack of knowledge on the strength of the explosion and the consequences for t

  10. 30 CFR 7.100 - Explosion tests.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Explosion tests. 7.100 Section 7.100 Mineral... Underground Coal Mines Where Permissible Electric Equipment is Required § 7.100 Explosion tests. (a) Test... agree. (ii) Remove all parts that do not contribute to the operation or ensure the...

  11. Recent advances in the molten salt destruction of energetic materials

    Energy Technology Data Exchange (ETDEWEB)

    Pruneda, C. O., LLNL

    1996-09-01

    We have demonstrated the use of the Molten Salt Destruction (MSD) Process for destroying explosives, liquid gun propellant, and explosives-contaminated materials on a 1.5 kg of explosive/hr bench- scale unit (1, 2, 3, 4, 5). In our recently constructed 5 kg/hr pilot- scale unit we have also demonstrated the destruction of a liquid gun propellant and simulated wastes containing HMX (octogen). MSD converts the organic constituents of the waste into non-hazardous substances such as carbon dioxide, nitrogen, and water. Any inorganic constituents of the waste, such as metallic particles, are retained in the molten salt. The destruction of energetic materials waste is accomplished by introducing it, together with air, into a vessel containing molten salt (a eutectic mixture of sodium, potassium, and lithium carbonates). The following pure explosives have been destroyed in our bench-scale experimental unit located at Lawrence Livermore National Laboratory`s (LLNL) High Explosives Applications Facility (HEAF): ammonium picrate, HMX, K- 6 (keto-RDX), NQ, NTO, PETN, RDX, TATB, and TNT. In addition, the following compositions were also destroyed: Comp B, LX- IO, LX- 1 6, LX- 17, PBX-9404, and XM46 (liquid gun propellant). In this 1.5 kg/hr bench-scale unit, the fractions of carbon converted to CO and of chemically bound nitrogen converted to NO{sub x} were found to be well below 1%. In addition to destroying explosive powders and compositions we have also destroyed materials that are typical of residues which result from explosives operations. These include shavings from machined pressed parts of plastic-bonded explosives and sump waste containing both explosives and non-explosive debris. Based on the process data obtained on the bench-scale unit we designed and constructed a next-generation 5 kg/hr pilot-scale unit, incorporating LLNL`s advanced chimney design. The pilot unit has completed process implementation operations and explosives safety reviews. To date, in this

  12. Hydrodynamics of Explosion Experiments and Models

    CERN Document Server

    Kedrinskii, Valery K

    2005-01-01

    Hydronamics of Explosion presents the research results for the problems of underwater explosions and contains a detailed analysis of the structure and the parameters of the wave fields generated by explosions of cord and spiral charges, a description of the formation mechanisms for a wide range of cumulative flows at underwater explosions near the free surface, and the relevant mathematical models. Shock-wave transformation in bubbly liquids, shock-wave amplification due to collision and focusing, and the formation of bubble detonation waves in reactive bubbly liquids are studied in detail. Particular emphasis is placed on the investigation of wave processes in cavitating liquids, which incorporates the concepts of the strength of real liquids containing natural microinhomogeneities, the relaxation of tensile stress, and the cavitation fracture of a liquid as the inversion of its two-phase state under impulsive (explosive) loading. The problems are classed among essentially nonlinear processes that occur unde...

  13. Morphomechanical Innovation Drives Explosive Seed Dispersal.

    Science.gov (United States)

    Hofhuis, Hugo; Moulton, Derek; Lessinnes, Thomas; Routier-Kierzkowska, Anne-Lise; Bomphrey, Richard J; Mosca, Gabriella; Reinhardt, Hagen; Sarchet, Penny; Gan, Xiangchao; Tsiantis, Miltos; Ventikos, Yiannis; Walker, Simon; Goriely, Alain; Smith, Richard; Hay, Angela

    2016-06-30

    How mechanical and biological processes are coordinated across cells, tissues, and organs to produce complex traits is a key question in biology. Cardamine hirsuta, a relative of Arabidopsis thaliana, uses an explosive mechanism to disperse its seeds. We show that this trait evolved through morphomechanical innovations at different spatial scales. At the organ scale, tension within the fruit wall generates the elastic energy required for explosion. This tension is produced by differential contraction of fruit wall tissues through an active mechanism involving turgor pressure, cell geometry, and wall properties of the epidermis. Explosive release of this tension is controlled at the cellular scale by asymmetric lignin deposition within endocarp b cells-a striking pattern that is strictly associated with explosive pod shatter across the Brassicaceae plant family. By bridging these different scales, we present an integrated mechanism for explosive seed dispersal that links evolutionary novelty with complex trait innovation. VIDEO ABSTRACT.

  14. [Explosion injuries - prehospital care and management].

    Science.gov (United States)

    Holsträter, Thorsten; Holsträter, Susanne; Rein, Daniela; Helm, Matthias; Hossfeld, Björn

    2013-11-01

    Explosion injuries are not restricted to war-like military conflicts or terrorist attacks. The emergency physician may also encounter such injuries in the private or industrial fields, injuries caused by fireworks or gas explosions. In such cases the injury patterns are especially complex and may consist of blunt and penetrating injuries as well as thermal damage. Emergency medical personnel must be prepared to cope with explosion trauma not only in individual cases but also in major casualty incidents (MCI). This necessitates a sound knowledge about the mechanisms and processes of an explosion as well as the particular pathophysiological relationships of explosion injuries in order to be able to initiate the best possible, guideline-conform trauma therapy.

  15. Explosion probability of unexploded ordnance: expert beliefs.

    Science.gov (United States)

    MacDonald, Jacqueline Anne; Small, Mitchell J; Morgan, M G

    2008-08-01

    This article reports on a study to quantify expert beliefs about the explosion probability of unexploded ordnance (UXO). Some 1,976 sites at closed military bases in the United States are contaminated with UXO and are slated for cleanup, at an estimated cost of $15-140 billion. Because no available technology can guarantee 100% removal of UXO, information about explosion probability is needed to assess the residual risks of civilian reuse of closed military bases and to make decisions about how much to invest in cleanup. This study elicited probability distributions for the chance of UXO explosion from 25 experts in explosive ordnance disposal, all of whom have had field experience in UXO identification and deactivation. The study considered six different scenarios: three different types of UXO handled in two different ways (one involving children and the other involving construction workers). We also asked the experts to rank by sensitivity to explosion 20 different kinds of UXO found at a case study site at Fort Ord, California. We found that the experts do not agree about the probability of UXO explosion, with significant differences among experts in their mean estimates of explosion probabilities and in the amount of uncertainty that they express in their estimates. In three of the six scenarios, the divergence was so great that the average of all the expert probability distributions was statistically indistinguishable from a uniform (0, 1) distribution-suggesting that the sum of expert opinion provides no information at all about the explosion risk. The experts' opinions on the relative sensitivity to explosion of the 20 UXO items also diverged. The average correlation between rankings of any pair of experts was 0.41, which, statistically, is barely significant (p= 0.049) at the 95% confidence level. Thus, one expert's rankings provide little predictive information about another's rankings. The lack of consensus among experts suggests that empirical studies

  16. Chemical analysis kit for the presence of explosives

    Science.gov (United States)

    Eckels, Joel Del [Livermore, CA; Nunes,; Peter, J [Danville, CA; Alcaraz, Armando [Livermore, CA; Whipple, Richard E [Livermore, CA

    2011-05-10

    A tester for testing for explosives associated with a test location comprising a first explosives detecting reagent; a first reagent holder, the first reagent holder containing the first explosives detecting reagent; a second explosives detecting reagent; a second reagent holder, the second reagent holder containing the second explosives detecting reagent; a sample collection unit for exposure to the test location, exposure to the first explosives detecting reagent, and exposure to the second explosives detecting reagent; and a body unit containing a heater for heating the sample collection unit for testing the test location for the explosives.

  17. Explosives, Genomics, and the Environment

    Directory of Open Access Journals (Sweden)

    Kieran C. O’Doherty

    2013-03-01

    Full Text Available RDX is an explosive that is also a neurotoxin and implicated in adverse health outcomes. Because of its widespread use in military and civilian operations, there is growing concern about potential environmental and health implications. One promising method of bioremediation involves genomic studies of soil microbes. These health concerns and technological issues intersect with social and political dimensions raising questions about public responses to genomic technologies and the degree of environmental accounting expected from the military. In cases of novel technologies entering into contested social spaces, public engagement can be useful to inform broader policy debates. Building on previous work, in this article, we outline the rationale, methods, and results of a public deliberation on these issues. To our knowledge, this is the first study of its kind on the issues of RDX pollution and microbial genomics, and thus provides an important baseline on public sentiment on these issues.

  18. Mass extinctions and supernova explosions

    CERN Document Server

    Korschinek, Gunther

    2016-01-01

    A nearby supernova (SN) explosion could have negatively influenced life on Earth, maybe even been responsible for mass extinctions. Mass extinction poses a significant extinction of numerous species on Earth, as recorded in the paleontologic, paleoclimatic, and geological record of our planet. Depending on the distance between the Sun and the SN, different types of threats have to be considered, such as ozone depletion on Earth, causing increased exposure to the Sun's ultraviolet radiation, or the direct exposure of lethal x-rays. Another indirect effect is cloud formation, induced by cosmic rays in the atmosphere which result in a drop in the Earth's temperature, causing major glaciations of the Earth. The discovery of highly intensive gamma ray bursts (GRBs), which could be connected to SNe, initiated further discussions on possible life-threatening events in Earth's history. The probability that GRBs hit the Earth is very low. Nevertheless, a past interaction of Earth with GRBs and/or SNe cannot be exclude...

  19. Nuclear explosives testing readiness evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Valk, T.C.

    1993-09-01

    This readiness evaluation considers hole selection and characterization, verification, containment issues, nuclear explosive safety studies, test authorities, event operations planning, canister-rack preparation, site preparation, diagnostic equipment setup, device assembly facilities and processes, device delivery and insertion, emplacement, stemming, control room activities, readiness briefing, arming and firing, test execution, emergency response and reentry, and post event analysis to include device diagnostics, nuclear chemistry, and containment. This survey concludes that the LLNL program and its supporting contractors could execute an event within six months of notification, and a second event within the following six months, given the NET group`s evaluation and the following three restraints: (1) FY94 (and subsequent year) funding is essentially constant with FY93, (2) Preliminary work for the initial event is completed to the historical sic months status, (3) Critical personnel, currently working in dual use technologies, would be recallable as needed.

  20. Explosive Detection and Identification by PGNAA

    Energy Technology Data Exchange (ETDEWEB)

    E.H. Seabury; A.J. Caffrey

    2004-11-01

    The goal of this project was to determine the feasibility of using field-portable prompt gamma-ray neutron activation analysis (PGNAA) to detect and identify explosives in improvised nuclear devices (INDs). The studies were carried out using the Monte Carlo N-Particle (MCNP) code developed at Los Alamos National Laboratory. The model results were tested experimentally using explosive simulants and the PINS PGNAA system developed at Idaho National Engineering and Environmental Laboratory (INEEL). The results of the MCNP calculations and PINS measurements are presented in this report. The calculations and measurements were in good agreement and indicate that most explosives are readily distinguishable from one another.

  1. Thermodynamic Model of Afterburning in Explosions

    Energy Technology Data Exchange (ETDEWEB)

    Kuhl, A L; Howard, M; Fried, L

    2003-04-23

    Thermodynamic states encountered during afterburning of explosion products gases in air were analyzed with the Cheetah code. Results are displayed in the form of Le Chatelier diagrams: the locus of states of specific internal energy versus temperature, for six different condensed explosives charges. Accuracy of the results was confirmed by comparing the fuel and products curves with the heats of detonation and combustion, and species composition as measured in bomb calorimeter experiments. Results were fit with analytic functions u = f ( T ) suitable for specifying the thermodynamic properties required for gas-dynamic models of afterburning in explosions.

  2. Study on Property of Desensitized Explosive Film

    Institute of Scientific and Technical Information of China (English)

    李国新; 王晓丽; 焦清介; 刘淑珍

    2004-01-01

    The mechanical sensitivity, the critical thickness of detonation wave propagation and detonation velocity of desensitized PETN film were studied by experiments. The relationship between the mass of desensitizer paraffin wax and the friction sensitivity of desensitized PETN film was tested. According to the microstructure of film, the function of desensitizer was explained. It was proved that the explosive film could make explosive element micromation and kept its inherence properties by the result of testing the propagating critical dimension of the desensitized PETN film detonation wave. The explosive velocity of confined desensitized PETN film was tested by the multiplex optical fibre.

  3. Water waves generated by underwater explosion

    CERN Document Server

    Mehaute, Bernard Le

    1996-01-01

    This is the first book on explosion-generated water waves. It presents the theoretical foundations and experimental results of the generation and propagation of impulsively generated waves resulting from underwater explosions. Many of the theories and concepts presented herein are applicable to other types of water waves, in particular, tsunamis and waves generated by the fall of a meteorite. Linear and nonlinear theories, as well as experimental calibrations, are presented for cases of deep and shallow water explosions. Propagation of transient waves on dissipative, nonuniform bathymetries to

  4. On the Violence of High Explosive Reactions

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Rotationally resolved infrared spectra of the explosive bouquet compounds associated with C-4 explosives

    Science.gov (United States)

    Clasp, Trocia N.; Johnson, Tiffani; Sullivan, Michael N.; Reeve, Scott W.

    2011-05-01

    The explosive material known as Composition C4, or simply C4, is an RDX based military grade explosive. RDX itself possesses a negligible vapor pressure at room temperature suggesting it is not a good target for conventional instruments designed to detect vapor phase chemical compounds. Recent research with canines has indicated that a better approach for detecting explosive vapors such as C4 is to focus on a characteristic mixture of impurities associated with the material. These characteristic mixtures of impurity vapors are referred to by canine researchers as the explosive bouquet and are fairly unique to the specific energetic material. In this paper, we will examine and report rotationally resolved infrared spectral signatures for the known compounds comprising the explosive bouquet for C4 based explosives including isobutylene, 2-ethyl-1-hexanol and cyclohexanone.

  6. Steam explosion pretreatment of softwood: the effect of the explosive decompression on enzymatic digestibility

    OpenAIRE

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

    2016-01-01

    Background 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. The information available about the effect of the explosive decompression on the biochemical conversion is, however, very limited, and no studies prove that the latter is actually enhanced by the explosion. Hence, it is of great value to discern between the effect of the ...

  7. HAZX Part 1. An Explosives Hazard Assessment Tool

    Science.gov (United States)

    2010-07-01

    hypergolic propellant spacecraft inside the NASA KSC VAB • Effect on 40 occupied buildings adjacent to VAB – On-rail explosion of a Lance Missile • Effect...on launch team in nearby control house Fire-Bee On Rail Explosion VAB spacecraft explosion at height On-rail explosion of Lance missile 23 DDESB

  8. 40 CFR 265.382 - Open burning; waste explosives.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Open burning; waste explosives. 265... DISPOSAL FACILITIES Thermal Treatment § 265.382 Open burning; waste explosives. Open burning of hazardous waste is prohibited except for the open burning and detonation of waste explosives. Waste explosives...

  9. 49 CFR 173.57 - Acceptance criteria for new explosives.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Acceptance criteria for new explosives. 173.57... § 173.57 Acceptance criteria for new explosives. (a) Unless otherwise excepted, an explosive substance... the Small-Scale Burning Test (Test Method 3(d)(i)), each as described in the Explosive Test Manual (UN...

  10. 30 CFR 75.1315 - Boreholes for explosives.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Boreholes for explosives. 75.1315 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1315 Boreholes for explosives. (a) All explosives fired underground shall be confined in boreholes except— (1) Sheathed...

  11. 30 CFR 75.1311 - Transporting explosives and detonators.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Transporting explosives and detonators. 75.1311... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1311 Transporting explosives and detonators. (a) When explosives and detonators are to be transported underground...

  12. 30 CFR 77.1300 - Explosives and blasting.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Explosives and blasting. 77.1300 Section 77... Explosives and Blasting § 77.1300 Explosives and blasting. (a) No explosives, blasting agent, detonator, or any other related blasting device or material shall be stored, transported, carried, handled,...

  13. Magnetorotational Explosive Instability in Keplerian Disks

    CERN Document Server

    Shtemler, Yuri; Mond, Michael

    2015-01-01

    In this paper it is shown that deferentially rotating disks that are in the presence of weak axial magnetic field are prone to a new nonlinear explosive instability. The latter occurs due to the near-resonance three-wave interactions of a magnetorotational instability with stable Alfven-Coriolis and magnetosonic modes. The dynamical equations that govern the temporal evolution of the amplitudes of the three interacting modes are derived. Numerical solutions of the dynamical equations indicate that small frequency mismatch gives rise to two types of behavior: 1. explosive instability which leads to infinite values of the three amplitudes within a finite time, and 2. bounded irregular oscillations of all three amplitudes. Asymptotic solutions of the dynamical equations are obtained for the explosive instability regimes and are shown to match the numerical solutions near the explosion time.

  14. Small-scale explosive welding of aluminum

    Science.gov (United States)

    Bement, L. J.

    1972-01-01

    Welding technique uses very small quantities of explosive ribbon to accomplish small-scale lap-welding of aluminum plates. Technique can perform small controlled welding with no length limitations and requires minimal protective shielding.

  15. Explosives Detection and Identification by PGNAA

    Energy Technology Data Exchange (ETDEWEB)

    E. H. Seabury; A. J. Caffrey

    2006-04-01

    The feasibility of using field-portable prompt gamma-ray neutron activation analysis (PGNAA) to detect and identify explosives in improvised nuclear devices has been studied computationally, using the Monte Carlo N-Particle (MCNP) code developed at Los Alamos National Laboratory. The Monte Carlo results, in turn were tested experimentally using explosive simulants and the PINS PGNAA system developed at Idaho National Laboratory (INL). The results of the MCNP calculations and PINS measurements have been previously reported. In this report we describe measurements performed on actual explosives and compare the results with calculations. The calculations and measurements were in good agreement and indicate that most explosives are readily distinguishable from one another by PGNAA

  16. Pretreatment of Corn Stalk by Steam Explosion

    Institute of Scientific and Technical Information of China (English)

    邵自强; 田永生; 谭惠民

    2003-01-01

    A steam explosion pretreatment, which is one of the best ways of pretreating plant stalk, is applied at various severities to corn stalk. It could effectively modify the super-molecular structure of corn stalk and defibrating corn stalk into individual components. The relationship between yield of reducing sugar and the operating conditions, including temperature, pressure of steam explosion pretreatment and acidity, is also established. Experimental results prove that the steam explosion substantially increases the yield of reducing sugar, and the optimal condition for steam explosion is as follows: the pressure is 2.0 MPa, the pressure-retaining time 300 s, the initial acid concentration 1% and the acid treatment time 24 h.

  17. Isolator fragmentation and explosive initiation tests

    Energy Technology Data Exchange (ETDEWEB)

    Dickson, Peter [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rae, Philip John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Foley, Timothy J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Novak, Alan M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Armstrong, Christopher Lee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Baca, Eva V. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gunderson, Jake Alfred [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-19

    Three tests were conducted to evaluate the effects of firing an isolator in proximity to a barrier or explosive charge. The tests with explosive were conducted without a barrier, on the basis that since any barrier will reduce the shock transmitted to the explosive, bare explosive represents the worst-case from an inadvertent initiation perspective. No reaction was observed. The shock caused by the impact of a representative plastic material on both bare and cased PBX 9501 is calculated in the worst-case, 1-D limit, and the known shock response of the HE is used to estimate minimum run-to-detonation lengths. The estimates demonstrate that even 1-D impacts would not be of concern and that, accordingly, the divergent shocks due to isolator fragment impact are of no concern as initiating stimuli.

  18. Isolator fragmentation and explosive initiation tests

    Energy Technology Data Exchange (ETDEWEB)

    Dickson, Peter [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Rae, Philip John [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Foley, Timothy J. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Novak, Alan M. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Armstrong, Christopher Lee [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Baca, Eva V. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Gunderson, Jake Alfred [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

    2015-09-30

    Three tests were conducted to evaluate the effects of firing an isolator in proximity to a barrier or explosive charge. The tests with explosive were conducted without barrier, on the basis that since any barrier will reduce the shock transmitted to the explosive, bare explosive represents the worst-case from an inadvertent initiation perspective. No reaction was observed. The shock caused by the impact of a representative plastic material on both bare and cased PBX9501 is calculated in the worst-case, 1-D limit, and the known shock response of the HE is used to estimate minimum run-to-detonation lengths. The estimates demonstrate that even 1-D impacts would not be of concern and that, accordingly, the divergent shocks due to isolator fragment impact are of no concern as initiating stimuli.

  19. Shunting effect in explosive electron emission

    Science.gov (United States)

    Mesyats, G. A.; Parkevich, E. V.; Pikuz, S. A.; Yalandin, M. I.

    2016-10-01

    An explanation is given to the results of an experiment on studying the explosive electron emission in a wire-cathode diode where a strongly nonuniform energy deposition into the wire material was observed using an X pinch as a radiation source for projection x-ray imaging. The specific input energy, contrary to the well-known observations, was not a maximum at the wire end, i.e., in the region of the strongest electric field, and the wire explosion occurred in the bulk, distant from the end. This is accounted for by the contribution of the wire side surface to explosive electron emission and by the gas desorption from the wire intensely heated by a current of density 108 A/cm2. Thus, the space between anode and cathode (wire end) is bridged by two plasmas: one generated due to the explosive electron emission from the wire side surface and the other produced from the desorbed gas.

  20. Rabbit lung injury induced by explosive decompression

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To study the mechanism of rabbit lunginjury caused by explosive decompression. Methods: A total of 42 rabbits and 10 rats were served as the experimental animals. A slow recompressiondecompression test and an explosive decompression test were applied to the animals, respectively. And the effects of the given tests on the animals were discussed. Results: The slow recompression-decompression did not cause an obvious lung injury, but the explosive decompression did cause lung injuries in different degrees. The greater the decompression range was, the shorter the decompression duration was, and the heavier the lung injuries were. Conclusions: Explosive decompression can cause a similar lung injury as shock wave does. The primary mechanical causes of the lung injury might be a tensile strain or stress in the alveolar wall and the pulmonary surface's impacts on the inside wall of the chest.