Sample records for tcb explosion role

  1. cis-Chlorobenzene Dihydrodiol Dehydrogenase (TcbB) from Pseudomonas sp. Strain P51, Expressed in Escherichia coli DH5α(pTCB149), Catalyzes Enantioselective Dehydrogenase Reactions

    PubMed Central

    Raschke, Henning; Fleischmann, Thomas; Van Der Meer, Jan Roelof; Kohler, Hans-Peter E.

    1999-01-01

    cis-Chlorobenzene dihydrodiol dehydrogenase (CDD) from Pseudomonas sp. strain P51, cloned into Escherichia coli DH5α(pTCB149) was able to oxidize cis-dihydrodihydroxy derivatives (cis-dihydrodiols) of dihydronaphthalene, indene, and four para-substituted toluenes to the corresponding catechols. During the incubation of a nonracemic mixture of cis-1,2-indandiol, only the (+)-cis-(1R,2S) enantiomer was oxidized; the (−)-cis-(S,2R) enantiomer remained unchanged. CDD oxidized both enantiomers of cis-1,2-dihydroxy-1,2,3,4-tetrahydronaphthalene, but oxidation of the (+)-cis-(1S,2R) enantiomer was delayed until the (−)-cis-(1R,2S) enantiomer was completely depleted. When incubated with nonracemic mixtures of para-substituted cis-toluene dihydrodiols, CDD always oxidized the major enantiomer at a higher rate than the minor enantiomer. When incubated with racemic 1-indanol, CDD enantioselectively transformed the (+)-(1S) enantiomer to 1-indanone. This stereoselective transformation shows that CDD also acted as an alcohol dehydrogenase. Additionally, CDD was able to oxidize (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene, (+)-cis-monochlorobiphenyl dihydrodiols, and (+)-cis-toluene dihydrodiol to the corresponding catechols. PMID:10583971

  2. cis-chlorobenzene dihydrodiol dehydrogenase (TcbB) from Pseudomonas sp. strain P51, expressed in Escherichia coli DH5alpha(pTCB149), catalyzes enantioselective dehydrogenase reactions.

    PubMed

    Raschke, H; Fleischmann, T; Van Der Meer, J R; Kohler, H P

    1999-12-01

    cis-Chlorobenzene dihydrodiol dehydrogenase (CDD) from Pseudomonas sp. strain P51, cloned into Escherichia coli DH5alpha(pTCB149) was able to oxidize cis-dihydrodihydroxy derivatives (cis-dihydrodiols) of dihydronaphthalene, indene, and four para-substituted toluenes to the corresponding catechols. During the incubation of a nonracemic mixture of cis-1,2-indandiol, only the (+)-cis-(1R,2S) enantiomer was oxidized; the (-)-cis-(S,2R) enantiomer remained unchanged. CDD oxidized both enantiomers of cis-1,2-dihydroxy-1,2,3, 4-tetrahydronaphthalene, but oxidation of the (+)-cis-(1S,2R) enantiomer was delayed until the (-)-cis-(1R,2S) enantiomer was completely depleted. When incubated with nonracemic mixtures of para-substituted cis-toluene dihydrodiols, CDD always oxidized the major enantiomer at a higher rate than the minor enantiomer. When incubated with racemic 1-indanol, CDD enantioselectively transformed the (+)-(1S) enantiomer to 1-indanone. This stereoselective transformation shows that CDD also acted as an alcohol dehydrogenase. Additionally, CDD was able to oxidize (+)-cis-(1R,2S)-dihydroxy-1, 2-dihydronaphthalene, (+)-cis-monochlorobiphenyl dihydrodiols, and (+)-cis-toluene dihydrodiol to the corresponding catechols.

  3. From Vulcanian explosions to sustained explosive eruptions: The role of diffusive mass transfer in conduit flow dynamics

    NASA Astrophysics Data System (ADS)

    Mason, R. M.; Starostin, A. B.; Melnik, O. E.; Sparks, R. S. J.

    2006-05-01

    Magmatic explosive eruptions are influenced by mass transfer processes of gas diffusion into bubbles caused by decompression. Melnik and Sparks [Melnik, O.E., Sparks, R.S.J. 2002, Modelling of conduit flow dynamic during explosive activity at Soufriere Hills Volcano, Montserrat. In: Druitt, T.H., Kokelaar, B.P. (eds). The Eruption of Soufriere Hills Volcano, Montserrat, from 1995 to 1999. Geological Society, London, Memoirs, 21, 307-317] proposed two end member cases corresponding to complete equilibrium and complete disequilibrium. In the first case, diffusion is fast enough to maintain the system near equilibrium and a long-lived explosive eruption develops. In the latter case, pre-existing bubbles expand under conditions of explosive eruption and decompression, but diffusive gas transfer is negligible. This leads to a much shorter eruption. Here we develop this model to consider the role of mass transfer by investigating transient flows at the start of an explosive eruption triggered by a sudden decompression. The simulations reveal a spectrum of behaviours from sustained to short-lived highly non-equilibrium Vulcanian-style explosions lasting a few tens of seconds, through longer lasting eruptions that can be sustained for tens of minutes and finally to eruptions that can last hours or even days. Behaviour is controlled by a mass-transfer parameter, ω, which equals n*2/3D, where n* is the bubble number density and D is the diffusivity. The parameter ω is expected to vary between 10 - 5 and 1 s - 1 in nature and reflects a time-scale for efficient diffusion. The spectrum of model behaviours is consistent with variations in styles of explosive eruptions of silicic volcanoes. In the initial stages peak discharges occur over 10-20 s and then decline to low discharges. If a critical bubble overpressure is assumed to be the criterion for fragmentation then fragmentation may stop and start several times in the declining period causing several pulses of high

  4. Experimental model of the role of cracks in the mechanism of explosive eruption of St. Helens-80

    NASA Astrophysics Data System (ADS)

    Kedrinskii, V. K.; Skulkin, A. A.

    2017-07-01

    A unique mini model of explosive volcano eruption through a formed system of cracks is developed. The process of crack formation and development is simulated by electric explosion of a conductor in a plate of optically transparent organic glass submerged into water. The explosion of a wire aligned with a through hole in the plate generates shock-wave loading along the plate and forms cracks. The fundamental role of high velocity flow in crack wedging by a high power hydrodynamic flow of a pulsating explosion cavity has been demonstrated.

  5. Thermal explosion violence of HMX-based explosives -- effect of composition, confinement and phase transition using the scaled thermal explosion experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maienschein, J L; Wardell, J F; Reaugh, J E

    We developed the Scaled Thermal Explosion Experiment (STEX) to provide a database of reaction violence from thermal explosion of explosives of interest. A cylinder of explosive, 1, 2 or 4 inches in diameter, is confined in a steel cylinder with heavy end caps, and heated under controlled conditions until it explodes. Reaction violence is quantified by micropower radar measurement of the cylinder wall velocity, and by strain gauge data at reaction onset. Here we describe the test concept and design, show that the conditions are well understood, and present initial data with HMX-based explosives. The HMX results show that anmore » explosive with high binder content yields less-violent reactions that an explosive with low binder content, and that the HMX phase at the time of explosion plays a key role in reaction violence.« less

  6. 49 CFR 172.522 - EXPLOSIVES 1.1, EXPLOSIVES 1.2 and EXPLOSIVES 1.3 placards.

    Code of Federal Regulations, 2010 CFR

    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...

  7. 49 CFR 172.522 - EXPLOSIVES 1.1, EXPLOSIVES 1.2 and EXPLOSIVES 1.3 placards.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 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...

  8. Non-detonable and non-explosive explosive simulators

    DOEpatents

    Simpson, Randall L.; Pruneda, Cesar O.

    1997-01-01

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

  9. Non-detonable and non-explosive explosive simulators

    DOEpatents

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

    1997-07-15

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

  10. Explosive simulants for testing explosive detection systems

    DOEpatents

    Kury, John W.; Anderson, Brian L.

    1999-09-28

    Explosives simulants that include non-explosive components are disclosed that facilitate testing of equipment designed to remotely detect explosives. The simulants are non-explosive, non-hazardous materials that can be safely handled without any significant precautions. The simulants imitate real explosives in terms of mass density, effective atomic number, x-ray transmission properties, and physical form, including moldable plastics and emulsions/gels.

  11. MODELING SNR CASSIOPEIA A FROM THE SUPERNOVA EXPLOSION TO ITS CURRENT AGE: THE ROLE OF POST-EXPLOSION ANISOTROPIES OF EJECTA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Orlando, S.; Miceli, M.; Pumo, M. L.

    The remnants of core-collapse supernovae (SNe) have complex morphologies that may reflect asymmetries and structures developed during the progenitor SN explosion. Here we investigate how the morphology of the supernova remnant Cassiopeia A (Cas A) reflects the characteristics of the progenitor SN with the aim of deriving the energies and masses of the post-explosion anisotropies responsible for the observed spatial distribution of Fe and Si/S. We model the evolution of Cas A from the immediate aftermath of the progenitor SN to the three-dimensional interaction of the remnant with the surrounding medium. The post-explosion structure of the ejecta is described bymore » small-scale clumping of material and larger-scale anisotropies. The hydrodynamic multi-species simulations consider an appropriate post-explosion isotopic composition of the ejecta. The observed average expansion rate and shock velocities can be well reproduced by models with ejecta mass M {sub ej} ≈ 4 M {sub ⊙} and explosion energy E {sub SN} ≈ 2.3 × 10{sup 51} erg. The post-explosion anisotropies (pistons) reproduce the observed distributions of Fe and Si/S if they had a total mass of ≈0.25 M {sub ⊙} and a total kinetic energy of ≈1.5 × 10{sup 50} erg. The pistons produce a spatial inversion of ejecta layers at the epoch of Cas A, leading to the Si/S-rich ejecta physically interior to the Fe-rich ejecta. The pistons are also responsible for the development of the bright rings of Si/S-rich material which form at the intersection between the reverse shock and the material accumulated around the pistons during their propagation. Our result supports the idea that the bulk of asymmetries observed in Cas A are intrinsic to the explosion.« less

  12. The role of community engagement in the adoption of new agricultural biotechnologies by farmers: the case of the Africa harvest tissue-culture banana in Kenya.

    PubMed

    Bandewar, Sunita V S; Wambugu, Florence; Richardson, Emma; Lavery, James V

    2017-03-13

    The tissue culture banana (TCB) is a biotechnological agricultural innovation that has been adopted widely in commercial banana production. In 2003, Africa Harvest Biotech Foundation International (AH) initiated a TCB program that was explicitly developed for smallholder farmers in Kenya to help them adopt the TCB as a scalable agricultural business opportunity. At the heart of the challenge of encouraging more widespread adoption of the TCB is the question: what is the best way to introduce the TCB technology, and all its attendant practices and opportunities, to smallholder farmers. In essence, a challenge of community or stakeholder engagement (CE). In this paper, we report the results of a case study of the CE strategies employed by AH to introduce TCB agricultural practices to small-hold farmers in Kenya, and their impact on the uptake of the TCB, and on the nature of the relationship between AH and the relevant community of farmers and other stakeholders. We identified six specific features of CE in the AH TCB project that were critical to its effectiveness: (1) adopting an empirical, "evidence-based" approach; (2) building on existing social networks; (3) facilitating farmer-to-farmer engagement; (4) focusing engagement on farmer groups; (5) strengthening relationships of trust through collaborative experiential learning; and (6) helping farmers to "learn the marketing game". We discuss the implications of AH's "values-based" approach to engagement, and how these guiding values functioned as "design constraints" for the key features of their CE strategy. And we highlight the importance of attention to the human dimensions of complex partnerships as a key determinant of successful CE. Our findings suggest new ways of conceptualizing the relationship between CE and the design and delivery of new technologies for global health and global development.

  13. Burn Propagation in a PBX 9501 Thermal Explosion

    NASA Astrophysics Data System (ADS)

    Henson, B. F.; Smilowitz, L.; Romero, J. J.; Sandstrom, M. M.; Asay, B. W.; Schwartz, C.; Saunders, A.; Merrill, F.; Morris, C.; Murray, M. M.; McNeil, W. V.; Marr-Lyon, M.; Rightley, P. M.

    2007-12-01

    We have applied proton radiography to study the conversion of solid density to gaseous combustion products subsequent to ignition of a thermal explosion in PBX 9501. We apply a thermal boundary condition to the cylindrical walls of the case, ending with an induction period at 205 C. We then introduce a laser pulse that accelerates the thermal ignition and synchronizes the explosion with the proton accelerator. We then obtain fast, synchronized images of the evolution of density loss with few microsecond resolution during the approximately 100 microsecond duration of the explosion. We present images of the solid explosive during the explosion and discuss measured rates and assumed mechanisms of burning the role of pressure in this internal burning.

  14. Understanding ultrafine nanodiamond formation using nanostructured explosives

    PubMed Central

    Pichot, Vincent; Risse, Benedikt; Schnell, Fabien; Mory, Julien; Spitzer, Denis

    2013-01-01

    The detonation process is able to build new materials with a bottom-up approach. Diamond, the hardest material on earth, can be synthesized in this way. This unconventional synthesis route is possible due to the presence of carbon inside the high-explosive molecules: firing high-explosive mixtures with a negative oxygen balance in a non-oxidative environment leads to the formation of nanodiamond particles. Trinitrotoluene (TNT) and hexogen (RDX) are the explosives primarily used to synthesize nanodiamonds. Here we show that the use of nanostructured explosive charges leads to the formation of smaller detonation nanodiamonds, and it also provides new understanding of nanodiamond formation-mechanisms. The discontinuity of the explosive at the nanoscale level plays the key role in modifying the diamond particle size, and therefore varying the size with microstructured charges is impossible. PMID:23831716

  15. Prediction of the explosion effect of aluminized explosives

    NASA Astrophysics Data System (ADS)

    Zhang, Qi; Xiang, Cong; Liang, HuiMin

    2013-05-01

    We present an approach to predict the explosion load for aluminized explosives using a numerical calculation. A code to calculate the species of detonation products of high energy ingredients and those of the secondary reaction of aluminum and the detonation products, velocity of detonation, pressure, temperature and JWL parameters of aluminized explosives has been developed in this study. Through numerical calculations carried out with this code, the predicted JWL parameters for aluminized explosives have been compared with those measured by the cylinder test. The predicted JWL parameters with this code agree with those measured by the cylinder test. Furthermore, the load of explosion for the aluminized explosive was calculated using the numerical simulation by using the JWL equation of state. The loads of explosion for the aluminized explosive obtained using the predicted JWL parameters have been compared with those using the measured JWL parameters. Both of them are almost the same. The numerical results using the predicted JWL parameters show that the explosion air shock wave is the strongest when the mass fraction of aluminum powder in the explosive mixtures is 30%. This result agrees with the empirical data.

  16. An explosion in Tunguska

    NASA Astrophysics Data System (ADS)

    Nistor, Ioan

    A detailed History of exploration of the place at Podkamennaya Tunguska, where a well known explosion has occured on 30 June 1908 is given with emphasys on the role by Leonid Kulik (1928-29). A short biography of Leonid Kulik is given. A review of subsequent expeditions is given. A review of existing theories concerning the explosion at Podkamennaya Tunguska on 30 June 1908 is given, including that of a meteor impact, asteroid impact, atomic explosion (F. Zigel and other), comet impact (V.G. Fesenkov and other). The theory sustained by author is that of a methan gas explosion initialazed by a meteor in a volume of about 0.25-2.5 billions m3 of methan. The shape of the place could be explained by few gaseous pouches, which could explode in a chain reaction. A review of similar explosions on the level of ground is given in the USSR as well as elsewhere. The soil fluidization is reviewed during earthquakes and similar phenomena. The original hypothesis by author was published in the "Lumea" N 41 magazin (Romania) on October 12 1989. The author disagree with atomic hypotesis enounced by F. Zigel, while the main factor of the explosion is the formation of one or few methan pouches above the soil. The programe of one of the most important international workshops (Tunguska 96 in Bologna on July 14-17) is attached. The site by Ioan Nistor gives a collection of informations about the event from elsewhere as well as the "gaseous pouches" hypothesis by the author.

  17. The effect of explosive percentage on underwater explosion energy release of hexanitrohexaazaisowurtzitane and octogen based aluminized explosives

    NASA Astrophysics Data System (ADS)

    Jiao, Qingjie; Wang, Qiushi; Nie, Jianxin; Guo, Xueyong; Zhang, Wei; Fan, Wenqi

    2018-03-01

    To control the explosion energy output by optimizing explosive components is a key requirement in a number of different application areas. The effect of different Al/O Ratio on underwater explosion of aluminized explosives has been studied detailedly. However, the effect of explosive percentage in the same Al/O Ratio is rarely researched, especially for Hexanitrohexaazaisowurtzitane (CL-20) based aluminized explosives. In this study, we performed the underwater explosion experiments with 1.2-kilogram explosives in order to investigate the explosion energy released from CL-20 and Octogen (HMX) based aluminized explosives. The percentage of the explosive varied from 5% to 30% and it is shown that: the shockwave peak pressure (pm) grows gradually; shock wave energy (Es) continues increasing, bubble energy (Eb) increases then decreases peaking at 15% for both formulas, and the total energy (E) and energy release rate (η) peak at 20% for CL-20 and 15% for HMX. This paper outlines the physical mechanism of Eb change under the influence of an aluminium initial reaction temperature and reaction active detonation product percentage coupling. The result shows that CL-20 is superior as a new high explosive and has promising application prospects in the regulation of explosive energy output for underwater explosives.

  18. Roles of Human CYP2A6 and Monkey CYP2A24 and 2A26 Cytochrome P450 Enzymes in the Oxidation of 2,5,2',5'-Tetrachlorobiphenyl.

    PubMed

    Shimada, Tsutomu; Kakimoto, Kensaku; Takenaka, Shigeo; Koga, Nobuyuki; Uehara, Shotaro; Murayama, Norie; Yamazaki, Hiroshi; Kim, Donghak; Guengerich, F Peter; Komori, Masayuki

    2016-12-01

    2,5,2',5'-Tetrachlorobiphenyl (TCB) induced type I binding spectra with cytochrome P450 (P450) 2A6 and 2A13, with K s values of 9.4 and 0.51 µM, respectively. However, CYP2A6 oxidized 2,5,2',5'-TCB to form 4-hydroxylated products at a much higher rate (∼1.0 minute -1 ) than CYP2A13 (∼0.02 minute -1 ) based on analysis by liquid chromatography-tandem mass spectrometry. Formation of 4-hydroxy-2,5,2',5'-TCB by CYP2A6 was greater than that of 3-hydroxy-2,5,2',5'-TCB and three other hydroxylated products. Several human P450 enzymes, including CYP1A1, 1A2, 1B1, 2B6, 2D6, 2E1, 2C9, and 3A4, did not show any detectable activities in oxidizing 2,5,2',5'-TCB. Cynomolgus monkey CYP2A24, which shows 95% amino acid identity to human CYP2A6, catalyzed 4-hydroxylation of 2,5,2',5'-TCB at a higher rate (∼0.3 minute -1 ) than CYP2A26 (93% identity to CYP2A6, ∼0.13 minute -1 ) and CYP2A23 (94% identity to CYP2A13, ∼0.008 minute -1 ). None of these human and monkey CYP2A enzymes were catalytically active in oxidizing other TCB congeners, such as 2,4,3',4'-, 3,4,3',4'-, and 3,5,3',5'-TCB. Molecular docking analysis suggested that there are different orientations of interaction of 2,5,2',5'-TCB with the active sites (over the heme) of human and monkey CYP2A enzymes, and that ligand interaction energies (U values) of bound protein-ligand complexes show structural relationships of interaction of TCBs and other ligands with active sites of CYP2A enzymes. Catalytic differences in human and monkey CYP2A enzymes in the oxidation of 2,5,2',5'-TCB are suggested to be due to amino acid changes at substrate recognition sites, i.e., V110L, I209S, I300F, V365M, S369G, and R372H, based on the comparison of primary sequences. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  19. Tailoring the sensitivity of initiating explosives

    NASA Astrophysics Data System (ADS)

    Manner, Virginia W.; Preston, Daniel N.; Snyder, Christopher J.; Dattelbaum, Dana M.; Tappan, Bryce C.

    2017-01-01

    Pentaerythritol tetranitrate (PETN) is a very common nitrate ester explosive that has been widely studied due to its use in military and commercial explosives. Recent experimental work and calculations have shown that substituting the central carbon atom of PETN with a silicon atom results in an extremely sensitive contact explosive. We have attempted to develop PETN derivatives which are less sensitive, by attaching hydrogen, amino, and methyl groups to the central carbon atom, and substituting the central carbon atom (and one -CH2ONO2 group) with phosphorous oxide. We relate the handling sensitivity properties of each PETN derivative to its structure, and discuss the role of the central atom, oxygen balance, thermal stability, and inter- and intramolecular hydrogen bonding on impact sensitivity.

  20. Explosives tester

    DOEpatents

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

    2011-01-11

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

  1. [The role of the biological damaging factor in the explosive injury].

    PubMed

    Popov, V L; Kadochnikov, D S; Minaeva, P V

    2015-01-01

    This article describes the specific features of the action of the biological damaging factors on the human organism associated with the explosive injury. Both the direct action of the damaging agents contained in the biological weapons and their secondary effects in the form of systemic and local infectious complications of the inflicted wounds are considered. The criteria for the evaluation of the degree of harm to the health of the victims of explosion attributable to the action of the biological damaging factor are proposed.

  2. Powdery Emulsion Explosive: A New Excellent Industrial Explosive

    NASA Astrophysics Data System (ADS)

    Ni, Ouqi; Zhang, Kaiming; Yu, Zhengquan; Tang, Shujuan

    2012-07-01

    Powdery emulsion explosive (PEE), a new powdery industrial explosive with perfect properties, has been made using an emulsification-spray drying technique. PEE is composed of 91-92.5 wt% ammonium nitrate (AN), 4.5-6 wt% organic fuels, and 1.5-1.8 wt% water. Due to its microstructure as a water-in-oil (W/O) emulsion and low water content, it has excellent detonation performance, outstanding water resistance, reliable safety, and good application compared with other industrial explosives, such as ammonite, emulsion explosives, and ANFO.

  3. Detection and dispersal of explosives by ants

    NASA Astrophysics Data System (ADS)

    McFee, John E.; Achal, Steve; Faust, Anthony A.; Puckrin, Eldon; House, Andrew; Reynolds, Damon; McDougall, William; Asquini, Adam

    2009-05-01

    The ability of animals to detect explosives is well documented. Mammalian systems, insects and even single celled organisms have all been studied and in a few cases employed to detect explosives. This paper will describe the potential ability of ants to detect, disperse and possibly neutralize bulk explosives. In spring 2008 a team of DRDC and Itres scientists conducted experiments on detecting surface-laid and buried landmines, improvised explosive devices (IEDs) and their components. Measurements were made using state-of-the-art short wave and thermal infrared hyperspectral imagers mounted on a personnel lift. During one of the early morning measurement sessions, a wispy, long linear trail was seen to emanate several meters from piles of explosives that were situated on the ground. Upon close visual inspection, it was observed that ants had found the piles of explosives and were carrying it to their ant hill, a distance of almost 20 meters from the piles. Initial analysis of the hyperspectral images clearly revealed the trail to the ant hill of explosives, despite being present in quantities not visible to the unaided eye. This paper details these observations and discusses them in the context of landmine and IED detection and neutralization. Possible reasons for such behaviour are presented. A number of questions regarding the behaviour, many pertinent to the use of ants in a counter-landmine/IED role, are presented and possible methods of answering them are discussed. Anecdotal evidence from deminers of detection and destruction of explosives by ants are presented.

  4. Numerical study of blast characteristics from detonation of homogeneous explosives

    NASA Astrophysics Data System (ADS)

    Balakrishnan, Kaushik; Genin, Franklin; Nance, Doug V.; Menon, Suresh

    2010-04-01

    A new robust numerical methodology is used to investigate the propagation of blast waves from homogeneous explosives. The gas-phase governing equations are solved using a hybrid solver that combines a higher-order shock capturing scheme with a low-dissipation central scheme. Explosives of interest include Nitromethane, Trinitrotoluene, and High-Melting Explosive. The shock overpressure and total impulse are estimated at different radial locations and compared for the different explosives. An empirical scaling correlation is presented for the shock overpressure, incident positive phase pressure impulse, and total impulse. The role of hydrodynamic instabilities to the blast effects of explosives is also investigated in three dimensions, and significant mixing between the detonation products and air is observed. This mixing results in afterburn, which is found to augment the impulse characteristics of explosives. Furthermore, the impulse characteristics are also observed to be three-dimensional in the region of the mixing layer. This paper highlights that while some blast features can be successfully predicted from simple one-dimensional studies, the growth of hydrodynamic instabilities and the impulsive loading of homogeneous explosives require robust three-dimensional investigation.

  5. On the violence of thermal explosion in solid explosives

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chidester, S.K.; Tarver, C.M.; Green, L.G.

    Heavily confined cylinders of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and triaminotrinitrobenzene (TATB) were heated at rates varying from 2 C/min to 3.3 C/h. Fourteen of the cylinders were hollow, and inner metallic liners with small heaters attached were used to produce uniform temperatures just prior to explosion. A complex thermocouple pattern was used to measure the temperature history throughout the charge and to determine the approximate location where the runaway exothermic reaction first occurred. The violence of the resulting explosion was measured using velocity pin arrays placed inside and outside of the metal confinement cylinders, flash x-rays, overpressure gauges, and fragment collection techniques.more » Five cylinders were intentionally detonated for violence comparisons. The measured temperature histories, times to explosion, and the locations of first reaction agreed closely with those calculated by a two-dimensional heat transfer code using multistep chemical decomposition models. The acceleration of the confining metal cylinders by the explosion process was accurately simulated using a two-dimensional pressure dependent deflagration reactive flow hydrodynamic mode. The most violent HMX thermal explosions gradually accelerated their outer cases to velocities approaching those of intentional detonations approximately 120 {micro}m after the onset of explosion. The measured inner cylinder collapse velocities from thermal explosions were considerably lower than those produced by detonations. In contrast to the HMX thermal reactions, no violent thermal explosions were produced by the TATB-based explosive LX-17. A heavily confined, slowly heated LX-17 test produced sufficient pressure to cause a 0.1 cm bend in a 2 cm thick steel plate.« less

  6. Computer simulation of explosion crater in dams with different buried depths of explosive

    NASA Astrophysics Data System (ADS)

    Zhang, Zhichao; Ye, Longzhen

    2018-04-01

    Based on multi-material ALE method, this paper conducted a computer simulation on the explosion crater in dams with different buried depths of explosive using LS-DYNA program. The results turn out that the crater size increases with the increase of buried depth of explosive at first, but closed explosion cavity rather than a visible crater is formed when the buried depth of explosive increases to some extent. The soil in the explosion cavity is taken away by the explosion products and the soil under the explosion cavity is compressed with its density increased. The research can provide some reference for the anti-explosion design of dams in the future.

  7. Biotransformation of explosives by Reticulitermes flavipes--associated termite Endosymbionts.

    PubMed

    Indest, Karl J; Eaton, Hillary L; Jung, Carina M; Lounds, Caly B

    2014-01-01

    Termites have an important role in the carbon and nitrogen cycles despite their reputation as destructive pests. With the assistance of microbial endosymbionts, termites are responsible for the conversion of complex biopolymers into simple carbon substrates. Termites also rely on endosymbionts for fixing and recycling nitrogen. As a result, we hypothesize that termite bacterial endosymbionts are a novel source of metabolic pathways for the transformation of nitrogen-rich compounds like explosives. Explosives transformation capability of termite (Reticulitermes flavipes)-derived endosymbionts was determined in media containing the chemical constituents nitrotriazolone (NTO) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) that comprise new insensitive explosive formulations. Media dosed with 40 µg/ml of explosive was inoculated with surface-sterilized, macerated termites. Bacterial isolates capable of explosives transformation were characterized by 16S rRNA sequencing. Termite-derived enrichment cultures demonstrated degradation activity towards the explosives NTO, RDX, as well as the legacy explosive 2,4,6-trinitrotoluene (TNT). Three isolates with high similarity to the Enterobacteriaceae(Enterobacter, Klebsiella) were able to transform TNT and NTO within 2 days, while isolates with high similarity to Serratia marcescens and Lactococcus lactis were able to transform RDX. Termite endosymbionts harbor a range of metabolic activities and possess unique abilities to transform nitrogen-rich explosives. © 2014 S. Karger AG, Basel.

  8. Nonideal detonation regimes in low density explosives

    NASA Astrophysics Data System (ADS)

    Ershov, A. P.; Kashkarov, A. O.; Pruuel, E. R.; Satonkina, N. P.; Sil'vestrov, V. V.; Yunoshev, A. S.; Plastinin, A. V.

    2016-02-01

    Measurements using Velocity Interferometer System for Any Reflector (VISAR) were performed for three high explosives at densities slightly above the natural loose-packed densities. The velocity histories at the explosive/window interface demonstrate that the grain size of the explosives plays an important role. Fine-grained materials produced rather smooth records with reduced von Neumann spike amplitudes. For commercial coarse-grained specimens, the chemical spike (if detectable) was more pronounced. This difference can be explained as a manifestation of partial burn up. In fine-grained explosives, which are more sensitive, the reaction can proceed partly within the compression front, which leads to a lower initial shock amplitude. The reaction zone was shorter in fine-grained materials because of higher density of hot spots. The noise level was generally higher for the coarse-grained explosives, which is a natural stochastic effect of the highly non-uniform flow of the heterogeneous medium. These results correlate with our previous data of electrical conductivity diagnostics. Instead of the classical Zel'dovich-von Neumann-Döring profiles, violent oscillations around the Chapman-Jouguet level were observed in about half of the shots using coarse-grained materials. We suggest that these unusual records may point to a different detonation wave propagation mechanism.

  9. Extrusion cast explosive

    DOEpatents

    Scribner, Kenneth J.

    1985-01-01

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

  10. Extrusion cast explosive

    DOEpatents

    Scribner, K.J.

    1985-01-29

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

  11. Extrusion cast explosive

    DOEpatents

    Scribner, K.J.

    1985-11-26

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

  12. Non-detonable explosive simulators

    DOEpatents

    Simpson, Randall L.; Pruneda, Cesar O.

    1994-01-01

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

  13. Non-detonable explosive simulators

    DOEpatents

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

    1994-11-01

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

  14. Optically detonated explosive device

    NASA Technical Reports Server (NTRS)

    Yang, L. C.; Menichelli, V. J. (Inventor)

    1974-01-01

    A technique and apparatus for optically detonating insensitive high explosives, is disclosed. An explosive device is formed by containing high explosive material in a house having a transparent window. A thin metallic film is provided on the interior surface of the window and maintained in contact with the high explosive. A laser pulse provided by a Q-switched laser is focussed on the window to vaporize the metallic film and thereby create a shock wave which detonates the high explosive. Explosive devices may be concurrently or sequentially detonated by employing a fiber optic bundle to transmit the laser pulse to each of the several individual explosive devices.

  15. Explosive death of conjugate coupled Van der Pol oscillators on networks

    NASA Astrophysics Data System (ADS)

    Zhao, Nannan; Sun, Zhongkui; Yang, Xiaoli; Xu, Wei

    2018-06-01

    Explosive death phenomenon has been gradually gaining attention of researchers due to the research boom of explosive synchronization, and it has been observed recently for the identical or nonidentical coupled systems in all-to-all network. In this work, we investigate the emergence of explosive death in networked Van der Pol (VdP) oscillators with conjugate variables coupling. It is demonstrated that the network structures play a crucial role in identifying the types of explosive death behaviors. We also observe that the damping coefficient of the VdP system not only can determine whether the explosive death state is generated but also can adjust the forward transition point. We further show that the backward transition point is independent of the network topologies and the damping coefficient, which is well confirmed by theoretical analysis. Our results reveal the generality of explosive death phenomenon in different network topologies and are propitious to promote a better comprehension for the oscillation quenching behaviors.

  16. Ammonium nitrate explosive systems

    DOEpatents

    Stinecipher, Mary M.; Coburn, Michael D.

    1981-01-01

    Novel explosives which comprise mixtures of ammonium nitrate and an ammonium salt of a nitroazole in desired ratios are disclosed. A preferred nitroazole is 3,5-dinitro-1,2,4-triazole. The explosive and physical properties of these explosives may readily be varied by the addition of other explosives and oxidizers. Certain of these mixtures have been found to act as ideal explosives.

  17. Testing of Confining Pressure Impacton Explosion Energy of Explosive Materials

    NASA Astrophysics Data System (ADS)

    Drzewiecki, Jan; Myszkowski, Jacek; Pytlik, Andrzej; Pytlik, Mateusz

    2017-06-01

    This paper presents the results of testing the explosion effects of two explosive charges placed in an environment with specified values of confining pressure. The aim of this study is to determine the impact of variable environmental conditions on the suitability of particular explosives for their use in the prevention of natural hazards in hard coal mining. The research results will contribute to improving the efficiency of currently adopted technologies of natural hazard prevention and aid in raising the level of occupational safety. To carry out the subject matter measurements, a special test stand was constructed which allows the value of the initial pressure inside the chamber, which constitutes its integral part, to be altered before the detonation of the charge being tested. The obtained characteristics of the pressure changes during the explosion of the analysed charge helped to identify the work (energy) which was produced during the process. The test results are a valuable source of information, opening up new possibilities for the use of explosives, the development of innovative solutions for the construction of explosive charges and their initiation.

  18. The role of community structure on the nature of explosive synchronization.

    PubMed

    Lotfi, Nastaran; Rodrigues, Francisco A; Darooneh, Amir Hossein

    2018-03-01

    In this paper, we analyze explosive synchronization in networks with a community structure. The results of our study indicate that the mesoscopic structure of the networks could affect the synchronization of coupled oscillators. With the variation of three parameters, the degree probability distribution exponent, the community size probability distribution exponent, and the mixing parameter, we could have a fast or slow phase transition. Besides, in some cases, we could have communities which are synchronized inside but not with other communities and vice versa. We also show that there is a limit in these mesoscopic structures which suppresses the transition from the second-order phase transition and results in explosive synchronization. This could be considered as a tuning parameter changing the transition of the system from the second order to the first order.

  19. Totally confined explosive welding

    NASA Technical Reports Server (NTRS)

    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.

  20. Steam explosion pretreatment of softwood: the effect of the explosive decompression on enzymatic digestibility.

    PubMed

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

    2016-01-01

    Steam explosion pretreatment has been examined in many studies for enhancing the enzymatic digestibility of lignocellulosic biomass and is currently the most common pretreatment method in commercial biorefineries. 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 explosion on the one hand and the steaming on the other hand, to identify their particular influences on enzymatic digestibility. The effect of the explosive decompression in the steam explosion pretreatment of spruce wood chips on their enzymatic cellulose digestibility was studied systematically. The explosion had a high influence on digestibility, improving it by up to 90 % compared to a steam pretreatment without explosion. Two factors were identified to be essentially responsible for the effect of the explosion on enzymatic digestibility: pretreatment severity and pressure difference of the explosion. A higher pretreatment severity can soften up and weaken the lignocellulose structure more, so that the explosion can better break up the biomass and decrease its particle size, which enhances its digestibility. In particular, increasing the pressure difference of the explosion leads to more defibration, a smaller particle size and a better digestibility. Though differences were found in the micro- and nanostructure of exploded and non-exploded biomass, the only influence of the explosion on digestibility was found to be the macroscopic particle size reduction. Steam explosion treatments with a high severity and a high pressure difference of the explosion lead to a comparatively high cellulose digestibility of the-typically very recalcitrant-softwood biomass. This is the first study to show that explosion can enhance the enzymatic digestibility of lignocellulosic biomass. If the

  1. Measurement of Afterburning Effect of Underoxidized Explosives by Underwater Explosion Method

    NASA Astrophysics Data System (ADS)

    Cao, Wei; He, Zhongqi; Chen, Wanghua

    2015-04-01

    The afterburning effect of TNT and a desensitized hexogen RDX-Al explosive was studied in a defined gas volume under water. A double-layer container (DLC) filled with different gases (air, oxygen, and nitrogen) was used to control and distinguish the afterburning effect of explosives. After the charges in the DLC were initiated under water, the shock wave signals were collected and analyzed. It is shown that shock wave peak pressures are duly in compliance with explosion similarity law, pressure, and impulse histories for explosions in oxygen and air are greater than those recorded for explosions in nitrogen due to the afterburing reaction. Moreover, the afterburning energy was calculated. Results show that even though there is excess oxygen in the gas volume, the afterburning energy may not reach the theoretically maximum value. This result is different from that in confined explosion, where the presence of excess oxygen in the compressed gas filling a bomb leads to complete combustion of the detonation products.

  2. A Chemical Monitoring Program of the Explosion Products in Underwater Explosion Tests

    DTIC Science & Technology

    1975-04-04

    CLASSIFICATION QF THIS PAGE- (When Date Entered) UNCLASSIFIED tL,URJTY CLASSIFICATION OF THIS PAGE(Then Data Entered) 20.and determination of various explosion...to institute a chemical monitoring program of the explosion products in underwater explosion tests, to determine monitoring parameters, and to...27 3.2.3 Samplers 28 3.2.4 Storage of Sediment Samples 32 IV. DETERMINATION OF EXPLOSION PRODUCTS 32 4.1 DESIGN OF MEASUREMENT SYSTEM 32 4.1.1

  3. Explosives Safety Requirements Manual

    DOT National Transportation Integrated Search

    1996-03-29

    This Manual describes the Department of Energy's (DOE's) explosives safety requirements applicable to operations involving the development, testing, handling, and processing of explosives or assemblies containing explosives. It is intended to reflect...

  4. A selfish gene governing pollen-pistil compatibility confers reproductive isolation between maize relatives.

    PubMed

    Kermicle, Jerry L

    2006-01-01

    Some populations of maize's closest relatives, the annual teosintes of Mexico, are unreceptive to maize pollen. When present in the pistil (silk and ovary) a number of maize genes discriminate against or exclude pollen not carrying the same allele. An analogous gene Tcb1-s was found in some teosinte populations but not in sympatric or parapatric maize. It was polymorphic among populations of teosinte growing wild, but regularly present in populations growing in intimate association with maize as a weed. Introduction of Tcb1-s into maize substantially to fully restored compatibility with Tcb1-s carrying teosintes. Although Tcb1-s pollen can fertilize tcb1 tcb1 maize, it is at a competitive disadvantage relative to tcb1 pollen. Hence, the influence of Tcb1-s on crossability is bidirectional. In the absence of maize, Tcb1-s can increase in teosinte populations without improving their fitness. In the presence of maize, Tcb1-s appears to have been co-opted to provide reproductive isolation for adaptation to a cultivated habitat.

  5. Relocatable explosives storage magazine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liptak, R.E.; Keenan, W.A.

    A relocatable storage magazine apparatus for storing and retrieving explosives and ordnance and for partially containing and attenuating the blast, conflagration and flying debris from an accidental explosion is described comprising: (a) a container having an access hole; (b) a debris trap attached to the container, the debris trap communicating with said container via the access hole, said debris trap having vent holes for venting the pressure of an explosion from said debris trap to the atmosphere; (c) means for covering said access hole; (d) means for suspending explosives and ordnance from the covering means; (e) means for entering themore » storage magazine to store and retrieve explosives and ordnance; (f) means for retaining said covering means in a position above the access hole wherein said explosives and ordnance are accessible from the entering means.« less

  6. Explosion containment device

    DOEpatents

    Benedick, William B.; Daniel, Charles J.

    1977-01-01

    The disclosure relates to an explosives storage container for absorbing and containing the blast, fragments and detonation products from a possible detonation of a contained explosive. The container comprises a layer of distended material having sufficient thickness to convert a portion of the kinetic energy of the explosion into thermal energy therein. A continuous wall of steel sufficiently thick to absorb most of the remaining kinetic energy by stretching and expanding, thereby reducing the momentum of detonation products and high velocity fragments, surrounds the layer of distended material. A crushable layer surrounds the continuous steel wall and accommodates the stretching and expanding thereof, transmitting a moderate load to the outer enclosure. These layers reduce the forces of the explosion and the momentum of the products thereof to zero. The outer enclosure comprises a continuous pressure wall enclosing all of the layers. In one embodiment, detonation of the contained explosive causes the outer enclosure to expand which indicates to a visual observer that a detonation has occurred.

  7. Fire and explosion hazards to flora and fauna from explosives.

    PubMed

    Merrifield, R

    2000-06-30

    Deliberate or accidental initiation of explosives can produce a range of potentially damaging fire and explosion effects. Quantification of the consequences of such effects upon the surroundings, particularly on people and structures, has always been of paramount importance. Information on the effects on flora and fauna, however, is limited, with probably the weakest area lying with fragmentation of buildings and their effects on different small mammals. Information has been used here to gain an appreciation of the likely magnitude of the potential fire and explosion effects on flora and fauna. This is based on a number of broad assumptions and a variety of data sources including World War II bomb damage, experiments performed with animals 30-40 years ago, and more recent field trials on building break-up under explosive loading.

  8. Optical detection of explosives: spectral signatures for the explosive bouquet

    NASA Astrophysics Data System (ADS)

    Osborn, Tabetha; Kaimal, Sindhu; Causey, Jason; Burns, William; Reeve, Scott

    2009-05-01

    Research with canines suggests that sniffer dogs alert not on the odor from a pure explosive, but rather on a set of far more volatile species present in an explosive as impurities. Following the explosive trained canine example, we have begun examining the vapor signatures for many of these volatile impurities utilizing high resolution spectroscopic techniques in several molecular fingerprint regions. Here we will describe some of these high resolution measurements and discuss strategies for selecting useful spectral signature regions for individual molecular markers of interest.

  9. Small-scale explosive seam welding. [using ribbon explosive encased in lead sheath

    NASA Technical Reports Server (NTRS)

    Bement, L. J.

    1972-01-01

    A unique small scale explosive seam welding technique is reported that has successfully joined a variety of aluminum alloys and alloy combinations in thicknesses to 0.125 inch, as well as titanium in thicknesses to 0.056 inch. The explosively welded joints are less than one-half inch in width and apparently have no long length limitation. The ribbon explosive developed in this study contains very small quantities of explosive encased in a flexible thin lead sheath. The evaluation and demonstration of this welding technique was accomplished in three phases: evaluation and optimization of ten major explosive welding variables, the development of four weld joints, and an applicational analysis which included photomicrographs, pressure integrity tests, vacuum effects, and fabrication of some potentially useful structures in aluminum and titanium.

  10. Synthesis of TiCx Powder via the Underwater Explosion of an Explosive

    NASA Astrophysics Data System (ADS)

    Tanaka, Shigeru; Bataev, Ivan; Hamashima, Hideki; Tsurui, Akihiko; Hokamoto, Kazuyuki

    2018-05-01

    In this study, a novel approach to the explosive synthesis of titanium carbide (TiC) is discussed. Nonstoichiometric TiCx powder was produced via the underwater explosion of a Ti powder encapsulated within a spherical explosive charge. The explosion process, bubble formation, and synthesis process were visualized using high-speed camera imaging. It was concluded that synthesis occurred within the detonation gas during the first expansion/contraction cycle of the bubble, which was accompanied by a strong emission of light. The recovered powders were studied using scanning electron microscopy and X-ray diffraction. Submicron particles were generated during the explosion. An increase in the carbon content of the starting powder resulted in an increase in the carbon content of the final product. No oxide byproducts were observed within the recovered powders.

  11. Research and Development of High-performance Explosives

    PubMed Central

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

    2016-01-01

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

  12. Seismic Methods of Identifying Explosions and Estimating Their Yield

    NASA Astrophysics Data System (ADS)

    Walter, W. R.; Ford, S. R.; Pasyanos, M.; Pyle, M. L.; Myers, S. C.; Mellors, R. J.; Pitarka, A.; Rodgers, A. J.; Hauk, T. F.

    2014-12-01

    Seismology plays a key national security role in detecting, locating, identifying and determining the yield of explosions from a variety of causes, including accidents, terrorist attacks and nuclear testing treaty violations (e.g. Koper et al., 2003, 1999; Walter et al. 1995). A collection of mainly empirical forensic techniques has been successfully developed over many years to obtain source information on explosions from their seismic signatures (e.g. Bowers and Selby, 2009). However a lesson from the three DPRK declared nuclear explosions since 2006, is that our historic collection of data may not be representative of future nuclear test signatures (e.g. Selby et al., 2012). To have confidence in identifying future explosions amongst the background of other seismic signals, and accurately estimate their yield, we need to put our empirical methods on a firmer physical footing. Goals of current research are to improve our physical understanding of the mechanisms of explosion generation of S- and surface-waves, and to advance our ability to numerically model and predict them. As part of that process we are re-examining regional seismic data from a variety of nuclear test sites including the DPRK and the former Nevada Test Site (now the Nevada National Security Site (NNSS)). Newer relative location and amplitude techniques can be employed to better quantify differences between explosions and used to understand those differences in term of depth, media and other properties. We are also making use of the Source Physics Experiments (SPE) at NNSS. The SPE chemical explosions are explicitly designed to improve our understanding of emplacement and source material effects on the generation of shear and surface waves (e.g. Snelson et al., 2013). Finally we are also exploring the value of combining seismic information with other technologies including acoustic and InSAR techniques to better understand the source characteristics. Our goal is to improve our explosion models

  13. Inspection tester for explosives

    DOEpatents

    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.

  14. Inspection tester for explosives

    DOEpatents

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

    2010-10-05

    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.

  15. Research on the analytical method about influence of gas leakage and explosion on subway

    NASA Astrophysics Data System (ADS)

    Ji, Wendong; Yang, Ligong; Chen, Lin

    2018-05-01

    With the construction and development of city subway, the cross impact of underground rail transit and gas pipe network is becoming more and more serious, but there is no analytical method for the impact of gas explosions on the subway. According to this paper, the gas leakage is equivalent to the TNT explosion equivalent, based on which, the calculation of the explosive impact load is carried out. On the basis of the concrete manifestation of gas explosion, it is more convenient to carry out the subsequent calculation by equivalently treating the explosive impact load as a uniform load within a certain range. The overlying soil of the subway station has played a protective role for the subway, making the displacement of the subway structure in the explosion process significantly reduced. The analysis on the actual case shows that this method can be successfully applied to the quantitative analysis of such accidents.

  16. The role of atmospheric nuclear explosions on the stagnation of global warming in the mid 20th century

    NASA Astrophysics Data System (ADS)

    Fujii, Yoshiaki

    2011-04-01

    This study suggests that the cause of the stagnation in global warming in the mid 20th century was the atmospheric nuclear explosions detonated between 1945 and 1980. The estimated GST drop due to fine dust from the actual atmospheric nuclear explosions based on the published simulation results by other researchers (a single column model and Atmosphere-Ocean General Circulation Model) has served to explain the stagnation in global warming. Atmospheric nuclear explosions can be regarded as full-scale in situ tests for nuclear winter. The non-negligible amount of GST drop from the actual atmospheric explosions suggests that nuclear winter is not just a theory but has actually occurred, albeit on a small scale. The accuracy of the simulations of GST by IPCC would also be improved significantly by introducing the influence of fine dust from the actual atmospheric nuclear explosions into their climate models; thus, global warming behavior could be more accurately predicted.

  17. Neutrino-Driven Explosions

    NASA Astrophysics Data System (ADS)

    Janka, Hans-Thomas

    The question why and how core-collapse supernovae (SNe) explode is one of the central and most long-standing riddles of stellar astrophysics. Solving this problem is crucial for deciphering the supernova (SN) phenomenon; for predicting its observable signals such as light curves and spectra, nucleosynthesis yields, neutrinos, and gravitational waves; for defining the role of SNe in the dynamical and chemo-dynamical evolution of galaxies; and for explaining the birth conditions and properties of neutron stars (NSs) and stellar-mass black holes. Since the formation of such compact remnants releases over hundred times more energy in neutrinos than the kinetic energy of the SN explosion, neutrinos can be the decisive agents for powering the SN outburst. According to the standard paradigm of the neutrino-driven mechanism, the energy transfer by the intense neutrino flux to the medium behind the stagnating core bounce shock, assisted by violent hydrodynamic mass motions (sometimes subsumed by the term "turbulence"), revives the outward shock motion and thus initiates the SN explosion. Because of the weak coupling of neutrinos in the region of this energy deposition, detailed, multidimensional hydrodynamic models including neutrino transport and a wide variety of physics are needed to assess the viability of the mechanism. Owing to advanced numerical codes and increasing supercomputer power, considerable progress has been achieved in our understanding of the physical processes that have to act in concert for the success of neutrino-driven explosions. First studies begin to reveal observational implications and avenues to test the theoretical picture by data from individual SNe and SN remnants but also from population-integrated observables. While models will be further refined, a real breakthrough is expected through the next galactic core-collapse SN, when neutrinos and gravitational waves can be used to probe the conditions deep inside the dying star.

  18. Totally confined explosive welding. [apparatus to reduce noise level and protect personnel during explosive bonding

    NASA Technical Reports Server (NTRS)

    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.

  19. Quantitative understanding of explosive stimulus transfer

    NASA Technical Reports Server (NTRS)

    Schimmel, M. L.

    1973-01-01

    The mechanisms of detonation transfer across hermetically sealed interfaces created by necessary interruptions in high explosive trains, such as at detonators to explosive columns, field joints in explosive columns, and components of munitions fuse trains are demostrated. Reliability of detonation transfer is limited by minimizing explosive quantities, the use of intensitive explosives for safety, and requirements to propagate across gaps and angles dictated by installation and production restraints. The major detonation transfer variables studied were: explosive quanity, sensitivity, and thickness, and the separation distances between donor and acceptor explosives.

  20. DOE explosives safety manual

    NASA Astrophysics Data System (ADS)

    1990-05-01

    The Department of Energy (DOE) policy requires that all activities be conducted in a manner that protects the safety of the public and provides a safe and healthful workplace for employees. DOE has also prescribed that all personnel be protected in any explosives operation undertaken. The level of safety provided shall be at least equivalent to that of the best industrial practice. The risk of death or serious injury shall be limited to the lowest practicable minimum. DOE and contractors shall continually review their explosives operations with the aim of achieving further refinements and improvements in safety practices and protective features. This manual describes the Department's explosive safety requirements applicable to operations involving the development, testing, handling, and processing of explosives or assemblies containing explosives. It is intended to reflect the state-of-the-art in explosives safety. In addition, it is essential that applicable criteria and requirements for implementing this policy be readily available and known to those responsible for conducting DOE programs. This document shall be periodically reviewed and updated to establish new requirements as appropriate. Users are requested to submit suggestions for improving the DOE Explosives Safety Manual through their appropriate Operations Office to the Office of Quality Programs.

  1. Modeling Explosion Induced Aftershocks

    NASA Astrophysics Data System (ADS)

    Kroll, K.; Ford, S. R.; Pitarka, A.; Walter, W. R.; Richards-Dinger, K. B.

    2017-12-01

    Many traditional earthquake-explosion discrimination tools are based on properties of the seismic waveform or their spectral components. Common discrimination methods include estimates of body wave amplitude ratios, surface wave magnitude scaling, moment tensor characteristics, and depth. Such methods are limited by station coverage and noise. Ford and Walter (2010) proposed an alternate discrimination method based on using properties of aftershock sequences as a means of earthquakeexplosion differentiation. Previous studies have shown that explosion sources produce fewer aftershocks that are generally smaller in magnitude compared to aftershocks of similarly sized earthquake sources (Jarpe et al., 1994, Ford and Walter, 2010). It has also been suggested that the explosion-induced aftershocks have smaller Gutenberg- Richter b-values (Ryall and Savage, 1969) and that their rates decay faster than a typical Omori-like sequence (Gross, 1996). To discern whether these observations are generally true of explosions or are related to specific site conditions (e.g. explosion proximity to active faults, tectonic setting, crustal stress magnitudes) would require a thorough global analysis. Such a study, however, is hindered both by lack of evenly distributed explosion-sources and the availability of global seismicity data. Here, we employ two methods to test the efficacy of explosions at triggering aftershocks under a variety of physical conditions. First, we use the earthquake rate equations from Dieterich (1994) to compute the rate of aftershocks related to an explosion source assuming a simple spring-slider model. We compare seismicity rates computed with these analytical solutions to those produced by the 3D, multi-cycle earthquake simulator, RSQSim. We explore the relationship between geological conditions and the characteristics of the resulting explosion-induced aftershock sequence. We also test hypothesis that aftershock generation is dependent upon the frequency

  2. Observations on military exploitation of explosives detection technologies

    NASA Astrophysics Data System (ADS)

    Faust, Anthony A.; de Ruiter, C. J.; Ehlerding, Anneli; McFee, John E.; Svinsås, Eirik; van Rheenen, Arthur D.

    2011-06-01

    Accurate and timely detection of explosives, energetic materials, and their associated compounds would provide valuable information to military commanders in a wide range of military operations: protection of fast moving convoys from mobile or static IED threats; more deliberate countermine and counter-IED operations during route or area clearance; and static roles such as hasty or deliberate checkpoints, critical infrastructure protection and support to public security. The detection of hidden explosive hazards is an extremely challenging problem, as evidenced by the fact that related research has been ongoing in many countries for at least seven decades and no general purpose solution has yet been found. Technologies investigated have spanned all major scientific fields, with emphasis on the physical sciences, life sciences, engineering, robotics, computer technology and mathematics. This paper will present a limited, operationally-focused overview of the current status of detection technologies. Emphasis will be on those technologies that directly detect the explosive hazard, as opposed to those that detect secondary properties of the threat, such as the casing, associated wires or electronics. Technologies that detect explosives include those based on nuclear radiation and terahertz radiation, as well as trace and biological detection techniques. Current research areas of the authors will be used to illustrate the practical applications.

  3. Nanoengineered explosives

    DOEpatents

    Makowiecki, D.M.

    1996-04-09

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

  4. Multi-dimensional simulations of core-collapse supernova explosions with CHIMERA

    NASA Astrophysics Data System (ADS)

    Messer, O. E. B.; Harris, J. A.; Hix, W. R.; Lentz, E. J.; Bruenn, S. W.; Mezzacappa, A.

    2018-04-01

    Unraveling the core-collapse supernova (CCSN) mechanism is a problem that remains essentially unsolved despite more than four decades of effort. Spherically symmetric models with otherwise high physical fidelity generally fail to produce explosions, and it is widely accepted that CCSNe are inherently multi-dimensional. Progress in realistic modeling has occurred recently through the availability of petascale platforms and the increasing sophistication of supernova codes. We will discuss our most recent work on understanding neutrino-driven CCSN explosions employing multi-dimensional neutrino-radiation hydrodynamics simulations with the Chimera code. We discuss the inputs and resulting outputs from these simulations, the role of neutrino radiation transport, and the importance of multi-dimensional fluid flows in shaping the explosions. We also highlight the production of 48Ca in long-running Chimera simulations.

  5. Neutron Star Kicks by the Gravitational Tug-boat Mechanism in Asymmetric Supernova Explosions: Progenitor and Explosion Dependence

    NASA Astrophysics Data System (ADS)

    Janka, Hans-Thomas

    2017-03-01

    Asymmetric mass ejection in the early phase of supernova (SN) explosions can impart a kick velocity to the new-born neutron star (NS). For neutrino-driven explosions the NS acceleration has been shown to be mainly caused by the gravitational attraction of the anisotropically expelled inner ejecta, while hydrodynamic forces contribute on a subdominant level, and asymmetric neutrino emission plays only a secondary role. Two- and three-dimensional hydrodynamic simulations have demonstrated that this gravitational tug-boat mechanism can explain the observed space velocities of young NSs up to more than 1000 km s-1. Here, we discuss how the NS kick depends on the energy, ejecta mass, and asymmetry of the SN explosion, and what role the compactness of the pre-collapse stellar core plays for the momentum transfer to the NS. We also provide simple analytic expressions for the NS velocity in terms of these quantities. Referring to results of hydrodynamic simulations in the literature, we argue why, within the discussed scenario of NS acceleration, electron-capture SNe, low-mass Fe-core SNe, and ultra-stripped SNe can be expected to have considerably lower intrinsic NS kicks than core-collapse SNe of massive stellar cores. Our basic arguments also remain valid if progenitor stars possess large-scale asymmetries in their convective silicon and oxygen burning layers. Possible scenarios for spin-kick alignment are sketched. Much of our discussion stays on a conceptual and qualitative level, and more work is necessary on the numerical modeling side to determine the dependences of involved parameters, whose prescriptions will be needed for recipes that can be used to better describe NS kicks in binary evolution and population synthesis studies.

  6. Large-Amplitude Deformation and Bond Breakage in Shock-Induced Reactions of Explosive Molecules

    NASA Astrophysics Data System (ADS)

    Kay, Jeffrey

    The response of explosive molecules to large-amplitude mechanical deformation plays an important role in shock-induced reactions and the initiation of detonation in explosive materials. In this presentation, the response of a series of explosive molecules (nitromethane, 2,4,6-trinitrotoluene [TNT], and 2,4,6-triamino-1,3,5-trinitrobenzene [TATB]) to a variety of large-amplitude deformations are examined using ab initio quantum chemical calculations. Large-amplitude motions that result in bond breakage are described, and the insights these results provide into both previous experimental observations and previous theoretical predictions of shock-induced reactions are discussed.

  7. Molecular hydrodynamics of high explosives

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Belak, J.

    1994-11-01

    High explosives release mechanical energy through chemical reactions. Applications of high explosives are vast in the mining and military industries and are beginning to see more civilian applications such as the deployment of airbags in modern automobiles. One of the central issues surrounding explosive materials is decreasing their sensitivity, necessary for their safe handling, while maintaining a high yield. Many practical tests have been devised to determine the sensitivity of explosive materials to shock, to impact, to spark, and to friction. These tests have great value in determining yield and setting precautions for safe handling but tell little of themore » mechanisms of initiation. How is the mechanical energy of impact or friction transformed into the chemical excitation that initiates explosion? The answer is intimately related to the structure of the explosive material, the size and distribution of grains, the size and presence of open areas such as voids and gas bubbles, and inevitably the bonding between explosive molecules.« less

  8. Two Sources of Nonisotropic Radiation From Underground Explosions in Granite

    DOE PAGES

    Vorobiev, O. Yu.

    2017-10-23

    Significant tangential ground motion observed during underground explosions makes it difficult to distinguish them from natural earthquakes. Such motion can be generated by the source geometry and emplacement conditions, by the heterogeneous nature of the rock mass (mechanical properties may vary in space due to the presence of cracks, joints, faults, and various geologic layers) and also by the nonuniform in situ stress state. The last mechanism is increasingly important with depth when the difference in main principal stresses becomes significant. This paper is focused on the role of material strength of the rock mass in generation of nonradial motionmore » during explosions in prestressed media. Numerical modeling of underground chemical explosions in granite at various depths has been conducted to compare two possible mechanisms of shear wave generation. The first, caused by rock mass anisotropy, is important at shallow depth. The second is related to elastic-plastic relaxation around the cavity created by the explosion. As a result, tangential motions for these two mechanisms have different signatures.« less

  9. Two Sources of Nonisotropic Radiation From Underground Explosions in Granite

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vorobiev, O. Yu.

    Significant tangential ground motion observed during underground explosions makes it difficult to distinguish them from natural earthquakes. Such motion can be generated by the source geometry and emplacement conditions, by the heterogeneous nature of the rock mass (mechanical properties may vary in space due to the presence of cracks, joints, faults, and various geologic layers) and also by the nonuniform in situ stress state. The last mechanism is increasingly important with depth when the difference in main principal stresses becomes significant. This paper is focused on the role of material strength of the rock mass in generation of nonradial motionmore » during explosions in prestressed media. Numerical modeling of underground chemical explosions in granite at various depths has been conducted to compare two possible mechanisms of shear wave generation. The first, caused by rock mass anisotropy, is important at shallow depth. The second is related to elastic-plastic relaxation around the cavity created by the explosion. As a result, tangential motions for these two mechanisms have different signatures.« less

  10. Insensitive fuze train for high explosives

    DOEpatents

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

    1994-01-01

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

  11. Snap, crack and pop of explosive fruit.

    PubMed

    Galstyan, Anahit; Hay, Angela

    2018-05-09

    There is an increasing appreciation for the role of physical forces in plant development. Mechanics are fundamental to how explosive fruit eject their seeds, and recent studies have successfully combined mechanics with developmental genetics to help explain how these dispersal traits are produced and how they evolved. Computational modeling is used more and more to address developmental questions, and explosive fruit are particularly good systems for combining biology and modeling approaches. Finite element models have been recently used to explore questions such as: Why do touch-me-not species with similar fruits, differ so much in how efficiently they transfer stored energy to eject seeds? And how do popping cress fruits use the expansive force of turgor pressure for tissue contraction? Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Explosion suppression system

    DOEpatents

    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.

  13. Sensitivities of ionic explosives

    NASA Astrophysics Data System (ADS)

    Politzer, Peter; Lane, Pat; Murray, Jane S.

    2017-03-01

    We have investigated the relevance for ionic explosive sensitivity of three factors that have been demonstrated to be related to the sensitivities of molecular explosives. These are (1) the maximum available heat of detonation, (2) the amount of free space per molecule (or per formula unit) in the crystal lattice and (3) specific features of the electrostatic potential on the molecular or ionic surface. We find that for ionic explosives, just as for molecular ones, there is an overall tendency for impact sensitivity to increase as the maximum detonation heat release is greater. This means that the usual emphasis upon designing explosives with large heats of detonation needs to be tempered somewhat. We also show that a moderate detonation heat release does not preclude a high level of detonation performance for ionic explosives, as was already demonstrated for molecular ones. Relating the free space per formula unit to sensitivity may require a modified procedure for ionic explosives; this will continue to be investigated. Finally, an encouraging start has been made in linking impact sensitivities to the electrostatic potentials on ionic surfaces, although limited so far to ammonium salts.

  14. Insensitive fuze train for high explosives

    DOEpatents

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

    1994-01-04

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

  15. Cell phone explosion.

    PubMed

    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. © The Author(s) 2015.

  16. Multi-dimensional simulations of core-collapse supernova explosions with CHIMERA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Messer, Bronson; Harris, James Austin; Hix, William Raphael

    Unraveling the core-collapse supernova (CCSN) mechanism is a problem that remains essentially unsolved despite more than four decades of effort. Spherically symmetric models with otherwise high physical fidelity generally fail to produce explosions, and it is widely accepted that CCSNe are inherently multi-dimensional. Progress in realistic modeling has occurred recently through the availability of petascale platforms and the increasing sophistication of supernova codes. We will discuss our most recent work on understanding neutrino-driven CCSN explosions employing multi-dimensional neutrino-radiation hydrodynamics simulations with the Chimera code. We discuss the inputs and resulting outputs from these simulations, the role of neutrino radiation transport,more » and the importance of multi-dimensional fluid flows in shaping the explosions. We also highlight the production of 48Ca in long-running Chimera simulations.« less

  17. Calibration methods for explosives detectors

    NASA Astrophysics Data System (ADS)

    MacDonald, Stephen J.; Rounbehler, David P.

    1992-05-01

    Airport security has become an important concern to cultures in every corner of the world. Presently, efforts to improve airport security have brought additional technological solutions, in the form of advanced instrumentation for the detection of explosives, into use at airport terminals in many countries. This new generation of explosives detectors is often used to augment existing security measures and provide a more encompassing screening capability for airline passengers. This paper describes two calibration procedures used for the Thermedics' EGIS explosives detectors. The systems were designed to screen people, electronic components, luggage, automobiles, and other objects for the presence of concealed explosives. The detectors have the ability to detect a wide range of explosives in both the vapor state or as surface adsorbed solids, therefore, calibrations were designed to challenge the system with explosives in each form.

  18. Free radical explosive composition

    DOEpatents

    Walker, Franklin E.; Wasley, Richard J.

    1979-01-01

    An improved explosive composition is disclosed and comprises a major portion of an explosive having a detonation velocity between about 1500 and 10,000 meters per second and a minor amount of a getter additive comprising a compound or mixture of compounds capable of capturing or deactivating free radicals or ions under mechanical or electrical shock conditions and which is not an explosive. Exemplary getter additives are isocyanates, olefins and iodine.

  19. Neutron Star Kicks by the Gravitational Tug-boat Mechanism in Asymmetric Supernova Explosions: Progenitor and Explosion Dependence

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Janka, Hans-Thomas

    Asymmetric mass ejection in the early phase of supernova (SN) explosions can impart a kick velocity to the new-born neutron star (NS). For neutrino-driven explosions the NS acceleration has been shown to be mainly caused by the gravitational attraction of the anisotropically expelled inner ejecta, while hydrodynamic forces contribute on a subdominant level, and asymmetric neutrino emission plays only a secondary role. Two- and three-dimensional hydrodynamic simulations have demonstrated that this gravitational tug-boat mechanism can explain the observed space velocities of young NSs up to more than 1000 km s{sup −1}. Here, we discuss how the NS kick depends onmore » the energy, ejecta mass, and asymmetry of the SN explosion, and what role the compactness of the pre-collapse stellar core plays for the momentum transfer to the NS. We also provide simple analytic expressions for the NS velocity in terms of these quantities. Referring to results of hydrodynamic simulations in the literature, we argue why, within the discussed scenario of NS acceleration, electron-capture SNe, low-mass Fe-core SNe, and ultra-stripped SNe can be expected to have considerably lower intrinsic NS kicks than core-collapse SNe of massive stellar cores. Our basic arguments also remain valid if progenitor stars possess large-scale asymmetries in their convective silicon and oxygen burning layers. Possible scenarios for spin-kick alignment are sketched. Much of our discussion stays on a conceptual and qualitative level, and more work is necessary on the numerical modeling side to determine the dependences of involved parameters, whose prescriptions will be needed for recipes that can be used to better describe NS kicks in binary evolution and population synthesis studies.« less

  20. Role of the 5-HT₂A receptor in the locomotor hyperactivity produced by phenylalkylamine hallucinogens in mice.

    PubMed

    Halberstadt, Adam L; Powell, Susan B; Geyer, Mark A

    2013-07-01

    The 5-HT₂A receptor mediates the effects of serotonergic hallucinogens and may play a role in the pathophysiology of certain psychiatric disorders, including schizophrenia. Given these findings, there is a need for animal models to assess the behavioral effects of 5-HT₂A receptor activation. Our previous studies demonstrated that the phenylalkylamine hallucinogen and 5-HT₂A/₂C agonist 2,5-dimethoxy-4-iodoamphetamine (DOI) produces dose-dependent effects on locomotor activity in C57BL/6J mice, increasing activity at low to moderate doses and reducing activity at high doses. DOI did not increase locomotor activity in 5-HT₂A knockout mice, indicating the effect is a consequence of 5-HT₂A receptor activation. Here, we tested a series of phenylalkylamine hallucinogens in C57BL/6J mice using the Behavioral Pattern Monitor (BPM) to determine whether these compounds increase locomotor activity by activating the 5-HT₂A receptor. Low doses of mescaline, 2,5-dimethoxy-4-ethylamphetamine (DOET), 2,5-dimethoxy-4-propylamphetamine (DOPR), 2,4,5-trimethoxyamphetamine (TMA-2), and the conformationally restricted phenethylamine (4-bromo-3,6-dimethoxybenzocyclobuten-1-yl)methylamine (TCB-2) increased locomotor activity. By contrast, the non-hallucinogenic phenylalkylamine 2,5-dimethoxy-4-tert-butylamphetamine (DOTB) did not alter locomotor activity at any dose tested (0.1-10 mg/kg i.p.). The selective 5-HT₂A antagonist M100907 blocked the locomotor hyperactivity induced by mescaline and TCB-2. Similarly, mescaline and TCB-2 did not increase locomotor activity in 5-HT₂A knockout mice. These results confirm that phenylalkylamine hallucinogens increase locomotor activity in mice and demonstrate that this effect is mediated by 5-HT₂A receptor activation. Thus, locomotor hyperactivity in mice can be used to assess phenylalkylamines for 5-HT₂A agonist activity and hallucinogen-like behavioral effects. These studies provide additional support for the link between 5

  1. Excitation of nonaxisymmetric perturbations by the axisymmetric explosive magnetorotational instability in Keplerian discs

    NASA Astrophysics Data System (ADS)

    Shtemler, Yu.; Mond, M.; Liverts, E.

    2018-02-01

    The excitation of nonaxisymmetric quasi-resonant triads by clustering around a dominant axisymmetric explosively unstable magnetorotational instability (MRI) in Keplerian discs is investigated. Clustering, namely, the mutual interactions of a large number of quasi-resonant triads that are connected by a single dominant explosively unstable axisymmetric triad, is invoked in order to provide a viable mechanism for the stabilization of the explosive nature of the latter. The results, however, are of wider scope as the proposed clustering scenario also provides a strong mechanism for the excitation of high-amplitude nonaxisymmetric perturbations. The latter play a major role in the nonlinear evolution of the MRI on the route to fully developed turbulence.

  2. The Role of Oxophytodienoate Reductases in the Detoxification of the Explosive 2,4,6-Trinitrotoluene by Arabidopsis1[W][OA

    PubMed Central

    Beynon, Emily R.; Symons, Zoe C.; Jackson, Rosamond G.; Lorenz, Astrid; Rylott, Elizabeth L.; Bruce, Neil C.

    2009-01-01

    The explosive 2,4,6-trinitrotoluene (TNT) is a significant environmental pollutant that is both toxic and recalcitrant to degradation. Phytoremediation is being increasingly proposed as a viable alternative to conventional remediation technologies to clean up explosives-contaminated sites. Despite the potential of this technology, relatively little is known about the innate enzymology of TNT detoxification in plants. To further elucidate this, we used microarray analysis to identify Arabidopsis (Arabidopsis thaliana) genes up-regulated by exposure to TNT and found that the expression of oxophytodienoate reductases (OPRs) increased in response to TNT. The OPRs share similarity with the Old Yellow Enzyme family, bacterial members of which have been shown to transform explosives. The three predominantly expressed forms, OPR1, OPR2, and OPR3, were recombinantly expressed and affinity purified. Subsequent biochemical characterization revealed that all three OPRs are able to transform TNT to yield nitro-reduced TNT derivatives, with OPR1 additionally producing the aromatic ring-reduced products hydride and dihydride Meisenheimer complexes. Arabidopsis plants overexpressing OPR1 removed TNT more quickly from liquid culture, produced increased levels of transformation products, and maintained higher fresh weight biomasses than wild-type plants. In contrast, OPR1,2 RNA interference lines removed less TNT, produced fewer transformation products, and had lower biomasses. When grown on solid medium, two of the three OPR1 lines and all of the OPR2-overexpressing lines exhibited significantly enhanced tolerance to TNT. These data suggest that, in concert with other detoxification mechanisms, OPRs play a physiological role in xenobiotic detoxification. PMID:19605548

  3. Effective centrality and explosive synchronization in complex networks

    NASA Astrophysics Data System (ADS)

    Navas, A.; Villacorta-Atienza, J. A.; Leyva, I.; Almendral, J. A.; Sendiña-Nadal, I.; Boccaletti, S.

    2015-12-01

    Synchronization of networked oscillators is known to depend fundamentally on the interplay between the dynamics of the graph's units and the microscopic arrangement of the network's structure. We here propose an effective network whose topological properties reflect the interplay between the topology and dynamics of the original network. On that basis, we are able to introduce the effective centrality, a measure that quantifies the role and importance of each network's node in the synchronization process. In particular, in the context of explosive synchronization, we use such a measure to assess the propensity of a graph to sustain an irreversible transition to synchronization. We furthermore discuss a strategy to induce the explosive behavior in a generic network, by acting only upon a fraction of its nodes.

  4. Detection of explosives in soils

    DOEpatents

    Chambers, William B.; Rodacy, Philip J.; Phelan, James M.; Woodfin, Ronald L.

    2002-01-01

    An apparatus and method for detecting explosive-indicating compounds in subsurface soil. The apparatus has a probe with an adsorbent material on some portion of its surface that can be placed into soil beneath the ground surface, where the adsorbent material can adsorb at least one explosive-indicating compound. The apparatus additional has the capability to desorb the explosive-indicating compound through heating or solvent extraction. A diagnostic instrument attached to the probe detects the desorbed explosive-indicating compound. In the method for detecting explosive-indicating compounds in soil, the sampling probe with an adsorbent material on at least some portion of a surface of the sampling probe is inserted into the soil to contact the adsorbent material with the soil. The explosive-indicating compounds are then desorbed and transferred as either a liquid or gas sample to a diagnostic tool for analysis. The resulting gas or liquid sample is analyzed using at least one diagnostic tool selected from the group consisting of an ion-mobility spectrometer, a gas chromatograph, a high performance liquid chromatograph, a capillary electrophoresis chromatograph, a mass spectrometer, a Fourier-transform infrared spectrometer and a Raman spectrometer to detect the presence of explosive-indicating compounds.

  5. The characterization and evaluation of accidental explosions

    NASA Technical Reports Server (NTRS)

    Strehlow, R. A.; Baker, W. E.

    1975-01-01

    Accidental explosions are discussed from a number of viewpoints. First, all accidental explosions, intentional explosions and natural explosions are characterized by type. Second, the nature of the blast wave produced by an ideal (point source or HE) explosion is discussed to form a basis for describing how other explosion processes yield deviations from ideal blast wave behavior. The current status blast damage mechanism evaluation is also discussed. Third, the current status of our understanding of each different category of accidental explosions is discussed in some detail.

  6. Explosively separable casing

    DOEpatents

    Jacobson, A.K.; Rychnovsky, R.E.; Visbeck, C.N.

    An explosively separable casing including a cylindrical afterbody and a circular cover for one end of the afterbody is disclosed. The afterbody has a cylindrical tongue extending longitudinally from one end which is matingly received in a corresponding groove in the cover. The groove is sized to provide a picket between the end of the tongue and the remainder of the groove so that an explosive can be located therein. A seal is also provided between the tongue and the groove for sealing the pocket from the atmosphere. A frangible holding device is utilized to hold the cover to the afterbody. When the explosive is ignited, the increase in pressure in the pocket causes the cover to be accelerated away from the afterbody. Preferably, the inner wall of the afterbody is in the same plane as the inner wall of the tongue to provide a maximum space for storage in the afterbody and the side wall of the cover is thicker than the side wall of the afterbody so as to provide a sufficiently strong surrounding portion for the pocket in which the explosion takes place. The detonator for the explosive is also located on the cover and is carried away with the cover during separation. The seal is preferably located at the longitudinal end of the tongue and has a chevron cross section.

  7. Explosively separable casing

    DOEpatents

    Jacobson, Albin K.; Rychnovsky, Raymond E.; Visbeck, Cornelius N.

    1985-01-01

    An explosively separable casing including a cylindrical afterbody and a circular cover for one end of the afterbody is disclosed. The afterbody has a cylindrical tongue extending longitudinally from one end which is matingly received in a corresponding groove in the cover. The groove is sized to provide a pocket between the end of the tongue and the remainder of the groove so that an explosive can be located therein. A seal is also provided between the tongue and the groove for sealing the pocket from the atmosphere. A frangible holding device is utilized to hold the cover to the afterbody. When the explosive is ignited, the increase in pressure in the pocket causes the cover to be accelerated away from the afterbody. Preferably, the inner wall of the afterbody is in the same plane as the inner wall of the tongue to provide a maximum space for storage in the afterbody and the side wall of the cover is thicker than the side wall of the afterbody so as to provide a sufficiently strong surrounding portion for the pocket in which the explosion takes place. The detonator for the explosive is also located on the cover and is carried away with the cover during separation. The seal is preferably located at the longitudinal end of the tongue and has a chevron cross section.

  8. 30 CFR 7.306 - Explosion tests.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Explosion tests. 7.306 Section 7.306 Mineral... MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Electric Motor Assemblies § 7.306 Explosion tests. (a) The following shall be used for conducting an explosion test: (1) An explosion test chamber designed...

  9. 30 CFR 7.306 - Explosion tests.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Explosion tests. 7.306 Section 7.306 Mineral... MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Electric Motor Assemblies § 7.306 Explosion tests. (a) The following shall be used for conducting an explosion test: (1) An explosion test chamber designed...

  10. 30 CFR 7.306 - Explosion tests.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Explosion tests. 7.306 Section 7.306 Mineral... MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Electric Motor Assemblies § 7.306 Explosion tests. (a) The following shall be used for conducting an explosion test: (1) An explosion test chamber designed...

  11. Big Explosives Experimental Facility - BEEF

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

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

  12. Big Explosives Experimental Facility - BEEF

    ScienceCinema

    None

    2018-01-16

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

  13. Spot test kit for explosives detection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pagoria, Philip F; Whipple, Richard E; Nunes, Peter J

    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 dispensermore » 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.« less

  14. Sensitivity to friction for primary explosives.

    PubMed

    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.

  15. Zirconium hydride containing explosive composition

    DOEpatents

    Walker, Franklin E.; Wasley, Richard J.

    1981-01-01

    An improved explosive composition is disclosed and comprises a major portion of an explosive having a detonation velocity between about 1500 and 10,000 meters per second and a minor amount of a donor additive comprising a non-explosive compound or mixture of non-explosive compounds which when subjected to an energy fluence of 1000 calories/cm.sup.2 or less is capable of releasing free radicals each having a molecular weight between 1 and 120. Exemplary donor additives are dibasic acids, polyamines and metal hydrides.

  16. Explosive scabbling of structural materials

    DOEpatents

    Bickes, Jr., Robert W.; Bonzon, Lloyd L.

    2002-01-01

    A new approach to scabbling of surfaces of structural materials is disclosed. A layer of mildly energetic explosive composition is applied to the surface to be scabbled. The explosive composition is then detonated, rubbleizing the surface. Explosive compositions used must sustain a detonation front along the surface to which it is applied and conform closely to the surface being scabbled. Suitable explosive compositions exist which are stable under handling, easy to apply, easy to transport, have limited toxicity, and can be reliably detonated using conventional techniques.

  17. Role of the 5-HT2A receptor in the locomotor hyperactivity produced by phenylalkylamine hallucinogens in mice

    PubMed Central

    Halberstadt, Adam L.; Powell, Susan B.; Geyer, Mark A.

    2014-01-01

    The 5-HT2A receptor mediates the effects of serotonergic hallucinogens and may play a role in the pathophysiology of certain psychiatric disorders, including schizophrenia. Given these findings, there is a need for animal models to assess the behavioral effects of 5-HT2A receptor activation. Our previous studies demonstrated that the phenylalkylamine hallucinogen and 5-HT2A/2C agonist 2,5-dimethoxy-4-iodoamphetamine (DOI) produces dose-dependent effects on locomotor activity in C57BL/6J mice, increasing activity at low to moderate doses and reducing activity at high doses. DOI did not increase locomotor activity in 5-HT2A knockout mice, indicating the effect is a consequence of 5-HT2A receptor activation. Here, we tested a series of phenylalkylamine hallucinogens in C57BL/6J mice using the Behavioral Pattern Monitor (BPM) to determine whether these compounds increase locomotor activity by activating the 5-HT2A receptor. Low doses of mescaline, 2,5-dimethoxy-4-ethylamphetamine (DOET), 2,5-dimethoxy-4-propylamphetamine (DOPR), 2,4,5-trimethoxyamphetamine (TMA-2), and the conformationally restricted phenethylamine (4-bromo-3,6-dimethoxybenzocyclobuten-1-yl)methylamine (TCB-2) increased locomotor activity. By contrast, the non-hallucinogenic phenylalkylamine 2,5-dimethoxy-4-tert-butylamphetamine (DOTB) did not alter locomotor activity at any dose tested (0.1-10 mg/kg i.p.). The selective 5-HT2A antagonist M100907 blocked the locomotor hyperactivity induced by mescaline and TCB-2. Similarly, mescaline and TCB-2 did not increase locomotor activity in 5-HT2A knockout mice. These results confirm that phenylalkylamine hallucinogens increase locomotor activity in mice and demonstrate that this effect is mediated by 5-HT2A receptor activation. Thus, locomotor hyperactivity in mice can be used to assess phenylalkylamines for 5-HT2A agonist activity and hallucinogen-like behavioral effects. These studies provide additional support for the link between 5-HT2A activation and

  18. The acoustic field in the ionosphere caused by an underground nuclear explosion

    NASA Astrophysics Data System (ADS)

    Krasnov, V. M.; Drobzheva, Ya. V.

    2005-07-01

    The problem of describing the generation and propagation of an infrasonic wave emitted by a finite extended source in the inhomogeneous absorbing atmosphere is the focus of this paper. It is of interest since the role of infrasonic waves in the energy balance of the upper atmosphere remains largely unknown. We present an algorithm, which allows adaptation of a point source model for calculating the infrasonic field from an underground nuclear explosion at ionospheric altitudes. Our calculations appear to agree remarkably well with HF Doppler sounding data measured for underground nuclear explosions at the Semipalatinsk Test Site. We show that the temperature and ionospheric electron density perturbation caused by an acoustic wave from underground nuclear explosion can reach 10% of background levels.

  19. Genetic and cellular analysis of cross-incompatibility in Zea mays.

    PubMed

    Lu, Yongxian; Kermicle, Jerry L; Evans, Matthew M S

    2014-03-01

    Three genetic systems conferring cross-incompatibility have been described in Zea mays: Teosinte crossing barrier1-strong (Tcb1-s) found in teosinte, and Gametophyte factor1-strong (Ga1-s) and Ga2-s found in maize and teosinte. The reproductive barrier between maize and some weedy teosintes is controlled by the Tcb1-s locus. Multi-generation inheritance experiments on two independent Tcb1-s lineages show that the Tcb1-s barrier is unstable in some maize lines. Reciprocal crosses between Tcb1-s tester plants and three recombinants in the Tcb1-s mapping region demonstrate that the Tcb1-s haplotype contains separable male and female components. In vivo assays of the dynamics of pollen tube growth and pollen tube morphology during rejection of incompatible pollen in silks carrying the Tcb1-s, Ga1-s, or Ga2-s barriers showed that, in all three, pollen tube growth is slower than in compatible crosses at early stages and had ceased by 24 h after pollination. In all three crossing barrier systems, incompatible pollen tubes have clustered callose plugs in contrast to pollen tubes of compatible crosses. Incompatible pollen tubes growing in the Tcb1-s, Ga1-s, and Ga2-s silks have different morphologies: straight, curved, and kinked, respectively. The distinct morphologies suggest that these crossing barriers block incompatible pollen through different mechanisms. This study lays the foundation for cloning the Tcb1 genes and provides clues about the cellular mechanisms involved in pollen rejection in the Tcb1-s, Ga1-s, and Ga2-s crossing barriers.

  20. The Interplay of Opacities and Rotation in Promoting the Explosion of Core-Collapse Supernovae

    NASA Astrophysics Data System (ADS)

    Vartanyan, David; Burrows, Adam; Radice, David

    2018-01-01

    For over five decades, the mechanism of explosion in core-collapse supernovae has been a central unsolved problem in astrophysics, challenging both our computational capabilities and our understanding of relevant physics. Current simulations often produce explosions, but they are at times underenergetic. The neutrino mechanism, wherein a fraction of emitted neutrinos is absorbed in the mantle of the star to reignite the stalled shock, remains the dominant model for reviving explosions in massive stars undergoing core collapse. We present here a diverse suite of 2D axisymmetric simulations produced by FORNAX, a highly parallelizable multidimensional supernova simulation code. We explore the effects of various corrections, including the many-body correction, to neutrino-matter opacities and the possible role of rotation in promoting explosion amongst various core-collapse progenitors.

  1. Stellar Explosions: Hydrodynamics and Nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Jose, Jordi

    2016-01-01

    Stars are the main factories of element production in the universe through a suite of complex and intertwined physical processes. Such stellar alchemy is driven by multiple nuclear interactions that through eons have transformed the pristine, metal-poor ashes leftover by the Big Bang into a cosmos with 100 distinct chemical species. The products of stellar nucleosynthesis frequently get mixed inside stars by convective transport or through hydrodynamic instabilities, and a fraction of them is eventually ejected into the interstellar medium, thus polluting the cosmos with gas and dust. The study of the physics of the stars and their role as nucleosynthesis factories owes much to cross-fertilization of different, somehow disconnected fields, ranging from observational astronomy, computational astrophysics, and cosmochemistry to experimental and theoretical nuclear physics. Few books have simultaneously addressed the multidisciplinary nature of this field in an engaging way suitable for students and young scientists. Providing the required multidisciplinary background in a coherent way has been the driving force for Stellar Explosions: Hydrodynamics and Nucleosynthesis. Written by a specialist in stellar astrophysics, this book presents a rigorous but accessible treatment of the physics of stellar explosions from a multidisciplinary perspective at the crossroads of computational astrophysics, observational astronomy, cosmochemistry, and nuclear physics. Basic concepts from all these different fields are applied to the study of classical and recurrent novae, type I and II supernovae, X-ray bursts and superbursts, and stellar mergers. The book shows how a multidisciplinary approach has been instrumental in our understanding of nucleosynthesis in stars, particularly during explosive events.

  2. Stellar Explosions: Hydrodynamics and Nucleosynthesis

    NASA Astrophysics Data System (ADS)

    José, Jordi

    2015-12-01

    Stars are the main factories of element production in the universe through a suite of complex and intertwined physical processes. Such stellar alchemy is driven by multiple nuclear interactions that through eons have transformed the pristine, metal-poor ashes leftover by the Big Bang into a cosmos with 100 distinct chemical species. The products of stellar nucleosynthesis frequently get mixed inside stars by convective transport or through hydrodynamic instabilities, and a fraction of them is eventually ejected into the interstellar medium, thus polluting the cosmos with gas and dust. The study of the physics of the stars and their role as nucleosynthesis factories owes much to cross-fertilization of different, somehow disconnected fields, ranging from observational astronomy, computational astrophysics, and cosmochemistry to experimental and theoretical nuclear physics. Few books have simultaneously addressed the multidisciplinary nature of this field in an engaging way suitable for students and young scientists. Providing the required multidisciplinary background in a coherent way has been the driving force for Stellar Explosions: Hydrodynamics and Nucleosynthesis. Written by a specialist in stellar astrophysics, this book presents a rigorous but accessible treatment of the physics of stellar explosions from a multidisciplinary perspective at the crossroads of computational astrophysics, observational astronomy, cosmochemistry, and nuclear physics. Basic concepts from all these different fields are applied to the study of classical and recurrent novae, type I and II supernovae, X-ray bursts and superbursts, and stellar mergers. The book shows how a multidisciplinary approach has been instrumental in our understanding of nucleosynthesis in stars, particularly during explosive events.

  3. Explosives tester with heater

    DOEpatents

    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.

  4. Discrimination of non-explosive and explosive samples through nitrocellulose fingerprints obtained by capillary electrophoresis.

    PubMed

    Fernández de la Ossa, Ma Ángeles; Ortega-Ojeda, Fernando; García-Ruiz, Carmen

    2013-08-09

    This work is focused on a novel procedure to discriminate nitrocellulose-based samples with non-explosive and explosive properties. The nitrocellulose study has been scarcely approached in the literature due to its special polymeric properties such as its high molar mass and complex chemical and structural characteristics. These properties require the nitrocellulose analysis to be performed by using a few organic solvents and in consequence, they limit the number of adequate analytical techniques for its study. In terms of identification of pre-blast explosives, mass spectrometry is one of the most preferred technique because it allows to obtain structural information. However, it has never been used to analyze polymeric nitrocellulose. In this study, the differentiation of non-explosive and explosive samples through nitrocellulose fingerprints obtained by capillary electrophoresis was investigated. A batch of 30 different smokeless gunpowders and 23 different everyday products were pulverized, derivatized with a fluorescent agent and analyzed by capillary electrophoresis with laser-induced fluorescence detection. Since this methodology is specific to d-glucopyranose derivatives (cellulosic and related compounds), and paper samples could be easily found in explosion scenes, 11 different paper samples were also included in the study as potential interference samples. In order to discriminate among samples, multivariate analysis (principal component analysis and soft independent modeling of class analogy) was applied to the obtained electrophoretic profiles. To the best of our knowledge, this represents the first study that achieve a successful discrimination between non-explosive and explosive nitrocellulose-based samples, as well as potential cellulose interference samples, and posterior classification of unknown samples into their corresponding groups using CE-LIF and chemometric tools. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. 27 CFR 70.445 - Commerce in explosives.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2013-04-01 2013-04-01 false Commerce in explosives. 70... Cartridges, and Explosives § 70.445 Commerce in explosives. Part 555 of title 27 CFR contains the regulations..., explosives, (b) Permits for users who buy or transport explosives in interstate or foreign commerce, (c...

  6. 27 CFR 70.445 - Commerce in explosives.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2012-04-01 2011-04-01 true Commerce in explosives. 70... Cartridges, and Explosives § 70.445 Commerce in explosives. Part 555 of title 27 CFR contains the regulations..., explosives, (b) Permits for users who buy or transport explosives in interstate or foreign commerce, (c...

  7. 27 CFR 70.445 - Commerce in explosives.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2014-04-01 2014-04-01 false Commerce in explosives. 70... Cartridges, and Explosives § 70.445 Commerce in explosives. Part 555 of title 27 CFR contains the regulations..., explosives, (b) Permits for users who buy or transport explosives in interstate or foreign commerce, (c...

  8. 27 CFR 70.445 - Commerce in explosives.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2011-04-01 2011-04-01 false Commerce in explosives. 70... Cartridges, and Explosives § 70.445 Commerce in explosives. Part 555 of title 27 CFR contains the regulations..., explosives, (b) Permits for users who buy or transport explosives in interstate or foreign commerce, (c...

  9. 27 CFR 70.445 - Commerce in explosives.

    Code of Federal Regulations, 2010 CFR

    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, (c...

  10. Seismic explosive charge loader and anchor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mcreynolds, O.B.

    1981-07-14

    An improved seismic explosive charge loader and anchor for loading and anchoring explosives in cylindrical containers in bore holes is disclosed, which includes a snap in spring band shaped anchor which effectively anchors the loader in the well bore against upward movement, one aspect of the invention includes a snap lock threaded connection for securing an explosive container having interrupted threads to the loader and anchor, and the loader and anchor is constructed and arranged to maintain a detonator in place in the explosive container thereby assuring detonation of the explosive.

  11. Method for fabricating non-detonable explosive simulants

    DOEpatents

    Simpson, Randall L.; Pruneda, Cesar O.

    1995-01-01

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

  12. Solid state gas sensors for detection of explosives and explosive precursors

    NASA Astrophysics Data System (ADS)

    Chu, Yun

    The increased number of terrorist attacks using improvised explosive devices (IEDs) over the past few years has made the trace detection of explosives a priority for the Department of Homeland Security. Considerable advances in early detection of trace explosives employing spectroscopic detection systems and other sensing devices have been made and have demonstrated outstanding performance. However, modern IEDs are not easily detectable by conventional methods and terrorists have adapted to avoid using metallic or nitro groups in the manufacturing of IEDs. Instead, more powerful but smaller compounds, such as TATP are being more frequently used. In addition, conventional detection techniques usually require large capital investment, labor costs and energy input and are incapable of real-time identification, limiting their application. Thus, a low cost detection system which is capable of continuous online monitoring in a passive mode is needed for explosive detection. In this dissertation, a thermodynamic based thin film gas sensor which can reliably detect various explosive compounds was developed and demonstrated. The principle of the sensors is based on measuring the heat effect associated with the catalytic decomposition of explosive compounds present in the vapor phase. The decomposition mechanism is complicated and not well known, but it can be affected by many parameters including catalyst, reaction temperature and humidity. Explosives that have relatively high vapor pressure and readily sublime at room temperature, like TATP and 2, 6-DNT, are ideal candidate for vapor phase detection using the thermodynamic gas sensor. ZnO, W2O 3, V2O5 and SnO2 were employed as catalysts. This sensor exhibited promising sensitivity results for TATP, but poor selectivity among peroxide based compounds. In order to improve the sensitivity and selectivity of the thermodynamic sensor, a Pd:SnO2 nanocomposite was fabricated and tested as part of this dissertation. A

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maienschein, J L; Wardell, J F

    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)more » 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.« less

  14. Trace explosives sensor testbed (TESTbed)

    NASA Astrophysics Data System (ADS)

    Collins, Greg E.; Malito, Michael P.; Tamanaha, Cy R.; Hammond, Mark H.; Giordano, Braden C.; Lubrano, Adam L.; Field, Christopher R.; Rogers, Duane A.; Jeffries, Russell A.; Colton, Richard J.; Rose-Pehrsson, Susan L.

    2017-03-01

    A novel vapor delivery testbed, referred to as the Trace Explosives Sensor Testbed, or TESTbed, is demonstrated that is amenable to both high- and low-volatility explosives vapors including nitromethane, nitroglycerine, ethylene glycol dinitrate, triacetone triperoxide, 2,4,6-trinitrotoluene, pentaerythritol tetranitrate, and hexahydro-1,3,5-trinitro-1,3,5-triazine. The TESTbed incorporates a six-port dual-line manifold system allowing for rapid actuation between a dedicated clean air source and a trace explosives vapor source. Explosives and explosives-related vapors can be sourced through a number of means including gas cylinders, permeation tube ovens, dynamic headspace chambers, and a Pneumatically Modulated Liquid Delivery System coupled to a perfluoroalkoxy total-consumption microflow nebulizer. Key features of the TESTbed include continuous and pulseless control of trace vapor concentrations with wide dynamic range of concentration generation, six sampling ports with reproducible vapor profile outputs, limited low-volatility explosives adsorption to the manifold surface, temperature and humidity control of the vapor stream, and a graphical user interface for system operation and testing protocol implementation.

  15. Near-Source Scattering of Explosion-Generated Rg: Insight From Difference Spectrograms of NTS Explosions

    NASA Astrophysics Data System (ADS)

    Gupta, I.; Chan, W.; Wagner, R.

    2005-12-01

    Several recent studies of the generation of low-frequency Lg from explosions indicate that the Lg wavetrain from explosions contains significant contributions from (1) the scattering of explosion-generated Rg into S and (2) direct S waves from the non-spherical spall source associated with a buried explosion. The pronounced spectral nulls observed in Lg spectra of Yucca Flats (NTS) and Semipalatinsk explosions (Patton and Taylor, 1995; Gupta et al., 1997) are related to Rg excitation caused by spall-related block motions in a conical volume over the shot point, which may be approximately represented by a compensated linear vector dipole (CLVD) source (Patton et al., 2005). Frequency-dependent excitation of Rg waves should be imprinted on all scattered P, S and Lg waves. A spectrogram may be considered as a three-dimensional matrix of numbers providing amplitude and frequency information for each point in the time series. We found difference spectrograms, derived from a normal explosion and a closely located over-buried shot recorded at the same common station, to be remarkably useful for an understanding of the origin and spectral contents of various regional phases. This technique allows isolation of source characteristics, essentially free from path and recording site effects, since the overburied shot acts as the empirical Green's function. Application of this methodology to several pairs of closely located explosions shows that the scattering of explosion-generated Rg makes significant contribution to not only Lg and its coda but also to the two other regional phases Pg (presumably by the scattering of Rg into P) and Sn. The scattered energy, identified by the presence of a spectral null at the appropriate frequency, generally appears to be more prominent in the somewhat later-arriving sections of Pg, Sn, and Lg than in the initial part. Difference spectrograms appear to provide a powerful new technique for understanding the mechanism of near-source scattering

  16. Method for fabricating non-detonable explosive simulants

    DOEpatents

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

    1995-05-09

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

  17. Thermally stable, plastic-bonded explosives

    DOEpatents

    Benziger, Theodore M.

    1979-01-01

    By use of an appropriate thermoplastic rubber as the binder, the thermal stability and thermal stress characteristics of plastic-bonded explosives may be greatly improved. In particular, an HMX-based explosive composition using an oil-extended styrene-ethylenebutylene-styrene block copolymer as the binder exhibits high explosive energy and thermal stability and good handling safety and physical properties.

  18. Low voltage nonprimary explosive detonator

    DOEpatents

    Dinegar, Robert H.; Kirkham, John

    1982-01-01

    A low voltage, electrically actuated, nonprimary explosive detonator is disclosed wherein said detonation is achieved by means of an explosive train in which a deflagration-to-detonation transition is made to occur. The explosive train is confined within a cylindrical body and positioned adjacent to low voltage ignition means have electrical leads extending outwardly from the cylindrical confining body. Application of a low voltage current to the electrical leads ignites a self-sustained deflagration in a donor portion of the explosive train which then is made to undergo a transition to detonation further down the train.

  19. Low Frequency Electromagnetic Pulse and Explosions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sweeney, J J

    2011-02-01

    This paper reviews and summarizes prior work related to low frequency (< 100 Hz) EMP (ElectroMagnetic Pulse) observed from explosions. It focuses on how EMP signals might, or might not, be useful in monitoring underground nuclear tests, based on the limits of detection, and physical understanding of these signals. In summary: (1) Both chemical and nuclear explosions produce an EMP. (2) The amplitude of the EMP from underground explosions is at least two orders of magnitude lower than from above ground explosions and higher frequency components of the signal are rapidly attenuated due to ground conductivity. (3) In general, inmore » the near field, that is distances (r) of less than 10s of kilometers from the source, the amplitude of the EMP decays approximately as 1/r{sup 3}, which practically limits EMP applications to very close (<{approx}1km) distances. (4) One computational model suggests that the EMP from a decoupled nuclear explosion may be enhanced over the fully coupled case. This has not been validated with laboratory or field data. (5) The magnitude of the EMP from an underground nuclear explosion is about two orders of magnitude larger than that from a chemical explosion, and has a larger component of higher frequencies. In principle these differences might be used to discriminate a nuclear from a chemical explosion using sensors at very close (<{approx}1 km) distances. (6) Arming and firing systems (e.g. detonators, exploding bridge wires) can also produce an EMP from any type of explosion. (7) To develop the understanding needed to apply low frequency EMP to nuclear explosion monitoring, it is recommended to carry out a series of controlled underground chemical explosions with a variety of sizes, emplacements (e.g. fully coupled and decoupled), and arming and firing systems.« less

  20. 3-D explosions: a meditation on rotation (and magnetic fields)

    NASA Astrophysics Data System (ADS)

    Wheeler, J. C.

    This is the text of an introduction to a workshop on asymmetric explosions held in Austin in June, 2003. The great progress in supernova research over thirty-odd years is briefly reviewed. The context in which the meeting was called is then summarized. The theoretical success of the intrinsically multidimensional delayed detonation paradigm in explaining the nature of Type Ia supernovae coupled with new techniques of observations in the near IR and with spectropolarimetry promise great advances in understanding binary progenitors, the explosion physics, and the ever more accurate application to cosmology. Spectropolarimetry has also revealed the strongly asymmetric nature of core collapse and given valuable perspectives on the supernova - gamma-ray burst connection. The capability of the magneto-rotational instability to rapidly create strong toroidal magnetic fields in the core collapse ambiance is outlined. This physics may be the precursor to driving MHD jets that play a role in asymmetric supernovae. Welcome to the brave new world of three-dimensional explosions!

  1. Effects of water states on steam explosion of lignocellulosic biomass.

    PubMed

    Sui, Wenjie; Chen, Hongzhang

    2016-01-01

    The work aimed to identify the complexity and roles of water states in steam explosion process of corn stalk to enhance the treatment efficiency. Results showed that two main water states with different mobility existed in corn stalk and influenced steam explosion treatment. By correlating dynamic water states data to feedstock mechanical properties and treatment process characteristics, the bound water being the excellent plasticizer that reduced the mechanical strength of fibers by over 30%, was conducive to treatment; while, the free water presenting buffering effects in treatment by hindering heat transfer which was reflected by the increase of temperature rising time by 1.29 folds and steam consumption by 2.18 folds, was not conducive. The distinguished point of these two waters was fiber saturated point. By considering treatment efficacy and energy consumption, the significance of fiber saturated point was highlighted as the optimal water states for steam explosion of corn stalk. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. The foliar uptake and downward translocation of trichloroethylene and 1,2,3-trichlorobenzene in air-plant-water systems.

    PubMed

    Su, Yuhong; Liang, Yongchao

    2013-05-15

    The foliar uptake and downward translocation of trichloroethylene (TCE) and 1,2,3-trichlorobenzene (TCB) in wheat, corn, and tomato seedlings were investigated following 2-48-h exposure of the plant shoots to vapor-contaminated air. The results showed that both TCE and TCB could be rapidly transported from air to plant rhizosphere solution through the foliar uptake and downward transport; the TCE and TCB concentrations in rhizosphere solutions increased with exposure time and external contaminant concentration. Among the three plant species studied, the TCE and TCB downward transport followed the order of wheat>tomato>corn. The transport efficiency of TCE by the three plants was far greater than that of TCB. With a 24-h uptake time, the amounts of TCE transported into the rhizosphere solution by wheat, tomato, and corn seedlings were 2.39 ± 0.42, 1.50 ± 0.22 and 1.45 ± 0.08 μg TCE per gram of fresh weight biomass, respectively, when the initial external TCE concentration was set at 12 mg l(-1). In a 48-h uptake experiment with corn seedlings, the TCE concentration in the rhizosphere solutions was lower in the TCE-TCB mixture system than in the single TCE system, whereas there was no significant difference in TCB concentration between the single TCB and TCE-TCB mixture systems at 48 h. The downward transport processes of TCE were inhibited, while those of TCB were enhanced in the mixed contaminant system within a 48-h uptake time. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Microbial bioreporters of trace explosives.

    PubMed

    Shemer, Benjamin; Koshet, Ori; Yagur-Kroll, Sharon; Belkin, Shimshon

    2017-06-01

    Since its introduction as an explosive in the late 19th century, 2,4,6-trinitrotoluene (TNT), along with other explosive compounds, has left numerous environmental marks. One of these is widespread soil and water pollution by trace explosives in military proving grounds, manufacturing facilities, or actual battlefields. Another dramatic impact is that exerted by the millions of landmines and other explosive devices buried in large parts of the world, causing extensive loss of life, injuries, and economical damage. In this review we highlight recent advances in the design and construction of microbial bioreporters, molecularly engineered to generate a quantifiable dose-dependent signal in the presence of trace amounts of explosives. Such sensor strains may be employed for monitoring environmental pollution as well as for the remote detection of buried landmines. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Comparative toxicology of tetrachlorobiphenyls in mink and rats. I. Changes in hepatic enzyme activity and smooth endoplasmic reticulum volume

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gillette, D.M.; Corey, R.D.; Helferich, W.G.

    1987-01-01

    Mink have been shown previously to be extraordinarily sensitive to polychlorinated biphenyls (PCBs) and related classes of halogenated hydrocarbons. This study explored several aspects of the acute response of mink to two purified tetrachlorobiphenyl (TCB) congeners and compared their response with that of the rat, a less sensitive and more thoroughly studied species. Young female pastel mink and young female Sprague-Dawley rats received three daily intraperitoneal injections with equimolar doses of either 2,4,2',4'-TCB or 3,4,3',4'-TCB, and were sacrificed after 7 days. Two control groups were used for each species; one was allowed free access to food and the other wasmore » pair-fed to the 3,4,3',4'-TCB treatment group. Rats remained clinically normal, while mink treated with 3,4,3',4'-TCB developed severe anorexia, diarrhea, and melena. Both species had significant increases in hepatic cytochrome P-450 content and the characteristic shift in the spectral maxima from 450 to 448 nm in the 3,4,3',4'-TCB- but not in the 2,4,2',4'-TCB-treated animals. Rats but not mink had increased activities of several hepatic monooxygenases in response to both congeners while microsomal epoxide hydrolase was increased in rats after 2,4,2',4'-TCB and in mink after 3,4,3',4'-TCB. Significant increases in the relative volume of smooth endoplasmic reticulum within hepatocytes of 2,4,2',4'-TCB-treated rats but not mink were confirmed by ultrastructural morphometry. Accumulation of both congeners was greater in adipose tissue than in the liver of either species. In both species, concentrations in adipose tissue were much greater for 2,4,2',4'-TCB than for 3,4,3',4'-TCB. PCB toxicosis in mink, as in other species, appeared to be dependent on isomeric arrangement of chlorine substituents. However, unlike other species, the toxicosis was not associated with biochemical or morphological evidence of hepatic enzyme induction.« less

  5. Detection of Explosive Vapors: The Roles of Exciton and Molecular Diffusion in Real-Time Sensing.

    PubMed

    Ali, Mohammad A; Shoaee, Safa; Fan, Shengqiang; Burn, Paul L; Gentle, Ian R; Meredith, Paul; Shaw, Paul E

    2016-11-04

    Time-resolved quartz crystal microbalance with in situ fluorescence measurements are used to monitor the sorption of the nitroaromatic (explosive) vapor, 2,4-dinitrotoluene (DNT) into a porous pentiptycene-containing poly(phenyleneethynylene) sensing film. Correlation of the nitroaromatic mass uptake with fluorescence quenching shows that the analyte diffusion follows the Case-II transport model, a film-swelling-limited process, in which a sharp diffusional front propagates at a constant velocity through the film. At a low vapor pressure of DNT of ≈16 ppb, the analyte concentration in the front is sufficiently high to give an average fluorophore-analyte separation of ≈1.5 nm. Hence, a long exciton diffusion length is not required for real-time sensing in the solid state. Rather the diffusion behavior of the analyte and the strength of the binding interaction between the analyte and the polymer play first-order roles in the fluorescence quenching process. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Conventional Weapons Underwater Explosions

    DTIC Science & Technology

    1988-12-01

    Nitromethane," UCRL 52903, December 1980. 22 I >I I 20 0--0 AIcN 23 0 I0 0 0 c W * ’S * / 0 o ---. 0 / nEil~ 24 Unreacted explosive Shock front t t...1976. 57 7. B. M. Dobratz LLNL Explosives Handbook - Properties of Explosives and Ex- plosive Simulants, UCRL -52997, March 1981. 8. M. H. Rice and J...Canada (403) 549- 3701 Ext. 4787 39. Joel C. W. Rogers Dept. of Mathemantics Polytechnic University 333 Jay Street Brooklyn, NY 11201 (718) 260-3501 40

  7. Normative data for the Tygerberg Cognitive Battery and Mini-Mental Status Examination in a South African population.

    PubMed

    Roos, Annerine; Calata, Dorothy; Jonkers, Liesl; Maritz, Stephan J; Kidd, Martin; Daniels, Willie M U; Hugo, Frans J

    2010-01-01

    Normative data for the Tygerberg Cognitive Battery (TCB) and Mini-Mental Status Examination (MMSE) (in South Africa) have not been formally examined before. The TCB was developed for the bedside pen-and-paper screening of cognitive impairment in each of the 6 main cognitive domains, including attention and concentration, speech, memory, praxis, gnosis, and executive functioning. The test is also used to diagnose different neuropsychiatric conditions. The MMSE is an established screen of cognitive status, which is often used as a comparative standard for novel screening tests such as the TCB. The TCB was initially developed in English and Afrikaans, and a Xhosa version was also initiated with this study so that the 3 most common languages of the region could be accommodated. The first aim of the study was to estimate normative test performance on the TCB and MMSE among controls, and the second aim was to develop a Xhosa version of the TCB. Assessments of the TCB and MMSE were carried out in a population of healthy individuals (n = 157). In addition, healthy Xhosa-speaking participants (n = 14) were screened using a Xhosa version of the TCB. Reliability scores for all forms of the TCB were satisfactory. Age and education correlated significantly with TCB scores (r = -0.26, P < .01; r = 0.64, P < .01, respectively), whereas only education significantly correlated with MMSE scores (r = 0.32, P < .05). Normative values were calculated accordingly, that is, controlled for the effects of age and education. The TCB scores also correlated significantly with MMSE scores (r = 0.49, P < .05), demonstrating the potential of the TCB to serve as an alternate cognitive assessment tool, along with the MMSE, to focus neuropsychiatric investigations. Scores on the Xhosa version differed significantly on speech, praxis, and gnosis between the Afrikaans and English participant scores. These normative data can be used to increase precision and to provide an impartial evaluation when

  8. Terrorism and Drug Trafficking: Responsibilities for Developing Explosives and Narcotics Detection Technologies

    DOT National Transportation Integrated Search

    1997-04-01

    This report discusses (1) the roles, responsibilities, and authority of : agencies that establish policy, provide funds or oversee funding requests, : and develop explosives and narcotics detection technologies; : (2) mechanisms used to coordinate th...

  9. The explosive origin of obsidian lava (Invited)

    NASA Astrophysics Data System (ADS)

    Castro, J. M.; Bindeman, I. N.; Tuffen, H.; Schipper, C.

    2013-12-01

    A long-standing challenge in volcanology has been to explain why explosive eruptions of rhyolite magma transition into outpourings of lava. Many studies suggest that lava is the product of non-explosive processes that allow magmatic vapour to escape in an open-system manner without wholesale fragmentation. Recent eruptions at Chaitén and Cordón Caulle volcanoes have shown that effusive rhyolites are anything but 'non-explosive' and may erupt simultaneously with vigourous pyroclastic fountains for months from a common vent. This behaviour implies that pyroclastic processes play a critical if not dominant role in degassing magma sufficiently such that it erupts effusively. Here we use H-isotope and bulk H2O measurements paired with textural evidence from the 2008 Chaitén and 2011 Cordón Caulle eruptions to demonstrate that effusion requires explosion(s)--lavas are the direct product of brittle deformation that fosters batched degassing into transient pyroclastic channels that repetitively and explosively vent from effusing lava. Evidence for cyclical brecciation and collapse of porous and permeable magmatic foams is abundant in the textures and structures of tuffisites--ash and lapilli-filled pyroclastic channels--found in volcanic bombs at both Chaitén and Cordón Caulle. We have used FTIR and a TCEA-MAT 253 system to precisely measure total water and D/H in erupted glass. Bulk H2O measurements on tuffisite and adjacent bomb obsidian indicate significantly lower H2O (~0.2-1.0 wt.%) in the tuffisite veins. These depletions imply effective local degassing and rapid advective transport of exsolved vapour through the veins. The H-isotopic signatures of tuffisites are also different from the hosting material insofar as being enriched in deuterium (up to -20‰). Such deuterium enrichments are inconsistent with isotope fractionation during both closed- and open-system degassing, but can be explained if an abundant and more primitive volatile phase from less degassed

  10. Explosive detection technology

    NASA Astrophysics Data System (ADS)

    Doremus, Steven; Crownover, Robin

    2017-05-01

    The continuing proliferation of improvised explosive devices is an omnipresent threat to civilians and members of military and law enforcement around the world. The ability to accurately and quickly detect explosive materials from a distance would be an extremely valuable tool for mitigating the risk posed by these devices. A variety of techniques exist that are capable of accurately identifying explosive compounds, but an effective standoff technique is still yet to be realized. Most of the methods being investigated to fill this gap in capabilities are laser based. Raman spectroscopy is one such technique that has been demonstrated to be effective at a distance. Spatially Offset Raman Spectroscopy (SORS) is a technique capable of identifying chemical compounds inside of containers, which could be used to detect hidden explosive devices. Coherent Anti-Stokes Raman Spectroscopy (CARS) utilized a coherent pair of lasers to excite a sample, greatly increasing the response of sample while decreasing the strength of the lasers being used, which significantly improves the eye safety issue that typically hinders laser-based detection methods. Time-gating techniques are also being developed to improve the data collection from Raman techniques, which are often hindered fluorescence of the test sample in addition to atmospheric, substrate, and contaminant responses. Ultraviolet based techniques have also shown significant promise by greatly improved signal strength from excitation of resonance in many explosive compounds. Raman spectroscopy, which identifies compounds based on their molecular response, can be coupled with Laser Induced Breakdown Spectroscopy (LIBS) capable of characterizing the sample's atomic composition using a single laser.

  11. Raman scattering spectroscopy for explosives identification

    NASA Astrophysics Data System (ADS)

    Nagli, L.; Gaft, M.

    2007-04-01

    Real time detection and identification of explosives at a standoff distance is a major issue in efforts to develop defense against so-called Improvised Explosive Devices (IED). It is recognized that the only technique, which is potentially capable to standoff detection of minimal amounts of explosives is laser-based spectroscopy. LDS technique belongs to trace detection, namely to its micro-particles variety. We applied gated Raman and time-resolved luminescence spectroscopy for detection of main explosive materials, both factory and homemade. Raman system was developed and tested by LDS for field remote detection and identification of minimal amounts of explosives on relevant surfaces at a distance of up to 30 meters.

  12. Chemical analysis kit for the presence of explosives

    DOEpatents

    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.

  13. Optical Pressure Measurements of Explosions

    DTIC Science & Technology

    2013-09-01

    near field detonation product gases can have a significant effect upon afterburn ignition times (4). The implication being that afterburning times...can be tuned to bring detonation product afterburning into proximity of the leading shock, influencing brisance, and explosive impulse on target. 3...R. Z.; McAndrew, B. A. Afterburn Ignition Delay and Shock Augmentation in Fuel Rich Solid Explosives. Propellants, Explosives, Pyrotechnics 2010

  14. Explosive plane-wave lens

    DOEpatents

    Marsh, S.P.

    1987-03-12

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 3 figs., 3 tabs.

  15. Explosive plane-wave lens

    DOEpatents

    Marsh, S.P.

    1988-03-08

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 4 figs.

  16. Explosive plane-wave lens

    DOEpatents

    Marsh, Stanley P.

    1988-01-01

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive.

  17. Standoff detection of explosive substances at distances of up to 150 m.

    PubMed

    Mukherjee, Anadi; Von der Porten, Steven; Patel, C Kumar N

    2010-04-10

    We report detection and identification of trace quantities of explosives at standoff distances up to 150 m with high sensitivity (signal-to-noise ratio of approximately 70) and high selectivity. The technique involves illuminating the target object with laser radiation at a wavelength that is strongly absorbed by the target. The resulting temperature rise is observed by remotely monitoring the increased blackbody radiation from the sample. An unambiguous determination of the target, TNT, in soil samples collected from an explosives test site in China Lake Naval Air Weapons Station is achieved through the use of a tunable CO(2) laser that scans over the absorption fingerprint of the target explosives. The theoretical analysis supports the observation and indicates that, with optimized detectors and data processing algorithms, the measurement capability can be improved significantly, permitting rapid standoff detection of explosives at distances approaching 1 km. The detection sensitivity varies as R(-2) and, thus, with the availability of high power, room-temperature, tunable mid-wave infrared and long-wave infrared quantum cascade lasers, this technology may play an important role in screening personnel and their belongings at short distances, such as in airports, for detecting and identifying explosives material residue on persons.

  18. Analysis of different materials subjected to open-air explosions in search of explosive traces by Raman microscopy.

    PubMed

    Zapata, Félix; García-Ruiz, Carmen

    2017-06-01

    Post-explosion scenes offer such chaos and destruction that evidence recovery and detection of post-blast residues from the explosive in the surrounding materials is highly challenging and difficult. The suitability of materials to retain explosives residues and their subsequent analysis has been scarcely investigated. Particularly, the use of explosive mixtures containing inorganic oxidizing salts to make improvised explosive devices (IEDs) is a current security concern due to their wide availability and lax control. In this work, a wide variety of materials such as glass, steel, plywood, plastic bag, brick, cardboard or cotton subjected to open-air explosions were examined using confocal Raman microscopy, aiming to detect the inorganic oxidizing salts contained in explosives as black powder, chloratite, dynamite, ammonium nitrate fuel oil and ammonal. Post-blast residues were detected through microscopic examination of materials surfaces. In general, the more homogeneous and smoother the surface was, the less difficulties and better results in terms of identification were obtained. However, those highly irregular surfaces were the most unsuitable collectors for the posterior identification of explosive traces by Raman microscopy. The findings, difficulties and some recommendations related to the identification of post-blast particles in the different materials studied are thoroughly discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Interplay of explosive thermal reaction dynamics and structural confinement

    NASA Astrophysics Data System (ADS)

    Perry, W. Lee; Zucker, Jonathan; Dickson, Peter M.; Parker, Gary R.; Asay, Blaine W.

    2007-04-01

    Explosives play a significant role in human affairs; however, their behavior in circumstances other than intentional detonation is poorly understood. Accidents may have catastrophic consequences, especially if additional hazardous materials are involved. Abnormal ignition stimuli, such as impact, spark, friction, and heat may lead to a very violent outcome, potentially including detonation. An important factor influencing the behavior subsequent to abnormal ignition is the strength and inertia of the vessel confining the explosive, i.e., the near-field structural/mechanical environment, also known as confinement (inertial or mechanical). However, a comprehensive and quantified understanding of how confinement affects reaction violence does not yet exist. In the research discussed here, we have investigated a wide range of confinement conditions and related the explosive response to the fundamentals of the combustion process in the explosive. In our experiments, a charge of an octahydrotetranitrotetrazine-based plastic bonded explosive (PBX 9501) was loaded into a gun assembly having variable confinement conditions and subjected to a heating profile. The exploding charge breached the confinement and accelerated a projectile down the gun barrel. High bandwidth pressure and volume measurements were made and a first-law analysis was used to obtain enthalpy and power from the raw data. These results were then used to quantify reaction violence. Enthalpy change and power ranged from 0-1.8 kJ and 0-12 MW for 300 mg charges, respectively. Below a confinement strength of 20 MPa, violence was found to decline precipitously with decreasing confinement, while the violence for the heaviest confinement experiments was found to be relatively constant. Both pressure and pressurization rate were found to have critical values to induce and sustain violent reaction.

  20. Lithium niobate explosion monitor

    DOEpatents

    Bundy, Charles H.; Graham, Robert A.; Kuehn, Stephen F.; Precit, Richard R.; Rogers, Michael S.

    1990-01-01

    Monitoring explosive devices is accomplished with a substantially z-cut lithium niobate crystal in abutment with the explosive device. Upon impact by a shock wave from detonation of the explosive device, the crystal emits a current pulse prior to destruction of the crystal. The current pulse is detected by a current viewing transformer and recorded as a function of time in nanoseconds. In order to self-check the crystal, the crystal has a chromium film resistor deposited thereon which may be heated by a current pulse prior to detonation. This generates a charge which is detected by a charge amplifier.

  1. Lithium niobate explosion monitor

    DOEpatents

    Bundy, C.H.; Graham, R.A.; Kuehn, S.F.; Precit, R.R.; Rogers, M.S.

    1990-01-09

    Monitoring explosive devices is accomplished with a substantially z-cut lithium niobate crystal in abutment with the explosive device. Upon impact by a shock wave from detonation of the explosive device, the crystal emits a current pulse prior to destruction of the crystal. The current pulse is detected by a current viewing transformer and recorded as a function of time in nanoseconds. In order to self-check the crystal, the crystal has a chromium film resistor deposited thereon which may be heated by a current pulse prior to detonation. This generates a charge which is detected by a charge amplifier. 8 figs.

  2. The behavior limestone under explosive load

    NASA Astrophysics Data System (ADS)

    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.

  3. 76 FR 64974 - Commerce in Explosives; List of Explosive Materials (2011R-18T)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-19

    ... [dinitropentano nitrile]. Dynamite. E EDDN [ethylene diamine dinitrate]. EDNA [ethylenedinitramine]. Ednatol. EDNP [ethyl 4,4-dinitropentanoate]. EGDN [ethylene glycol dinitrate]. Erythritol tetranitrate explosives..., trinitroglycerine]. Nitroglycide. Nitroglycol [ethylene glycol dinitrate, EGDN]. Nitroguanidine explosives...

  4. Patched Skin Bilirubin Assay to Monitor Neonates Born Extremely Preterm Undergoing Phototherapy.

    PubMed

    De Luca, Daniele; Dell'Orto, Valentina

    2017-09-01

    To verify the reliability and safety of transcutaneous bilirubin (TcB) measurements in patched skin areas in neonates born extremely preterm under phototherapy. Sixty neonates (<30 weeks' gestation) receiving phototherapy were enrolled and TcB was measured via a second-generation transcutaneous bilirubinometer in patched skin areas (of at least 2.5 cm diameter). Total serum bilirubin (TSB), lactate, pH, hemoglobin, and skin temperature were measured within 10 minutes of the TcB assay. Clinicians were blinded to TcB values, and clinical decisions about phototherapy were made with the TSB measurement only. TcB and TSB significantly were correlated (r = 0.84; P <.001), even after adjustment for hemoglobin, pH, lactate, gestational and postnatal age (standardized β = 0.8; P <.001; adjusted R 2  = 0.75), or treatment duration (standardized β = 0.8; P <.001; adjusted R 2  = 0.7). When the Bland-Altman analysis was used, TcB overestimated TSB at high values (mean difference TSB - TcB: -2.8 [2.4] mg/dL). If clinicians used the TcB only, no neonate would have had phototherapy stopped prematurely, and 21 (35%) would have continued phototherapy when it could have been stopped. The correlation between TSB and TcB (measured in patched skin areas) was comparable with that obtained in more mature neonates, and it was not influenced by clinical variables or factors affecting skin bilirubin passage. TcB overestimated TSB, and this may expose infants born preterm to unnecessary phototherapy, although it could spare approximately 65% of TSB assays. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. 33 CFR 401.68 - Explosives Permission Letter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... granted and the vessel shall not transit. (c) A written application for a Seaway Explosives Permission... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Explosives Permission Letter. 401... Permission Letter. (a) A Seaway Explosives Permission Letter is required for an explosive vessel in the...

  6. Concussive brain injury from explosive blast

    PubMed Central

    de Lanerolle, Nihal C; Hamid, Hamada; Kulas, Joseph; Pan, Jullie W; Czlapinski, Rebecca; Rinaldi, Anthony; Ling, Geoffrey; Bandak, Faris A; Hetherington, Hoby P

    2014-01-01

    Objective Explosive blast mild traumatic brain injury (mTBI) is associated with a variety of symptoms including memory impairment and posttraumatic stress disorder (PTSD). Explosive shock waves can cause hippocampal injury in a large animal model. We recently reported a method for detecting brain injury in soldiers with explosive blast mTBI using magnetic resonance spectroscopic imaging (MRSI). This method is applied in the study of veterans exposed to blast. Methods The hippocampus of 25 veterans with explosive blast mTBI, 20 controls, and 12 subjects with PTSD but without exposure to explosive blast were studied using MRSI at 7 Tesla. Psychiatric and cognitive assessments were administered to characterize the neuropsychiatric deficits and compare with findings from MRSI. Results Significant reductions in the ratio of N-acetyl aspartate to choline (NAA/Ch) and N-acetyl aspartate to creatine (NAA/Cr) (P < 0.05) were found in the anterior portions of the hippocampus with explosive blast mTBI in comparison to control subjects and were more pronounced in the right hippocampus, which was 15% smaller in volume (P < 0.05). Decreased NAA/Ch and NAA/Cr were not influenced by comorbidities – PTSD, depression, or anxiety. Subjects with PTSD without blast had lesser injury, which tended to be in the posterior hippocampus. Explosive blast mTBI subjects had a reduction in visual memory compared to PTSD without blast. Interpretation The region of the hippocampus injured differentiates explosive blast mTBI from PTSD. MRSI is quite sensitive in detecting and localizing regions of neuronal injury from explosive blast associated with memory impairment. PMID:25493283

  7. Role of Thermochemical Decomposition in Energetic Material Initiation Sensitivity and Explosive Performance

    DTIC Science & Technology

    2007-02-05

    Electronic excitation has been suggested as one contributing mechanistic step in a multiprocess detonation model [18], and such electronic...and, (b) Dick, J. J., Orientation Dependence of the Shock Initiation Sensitivity of PETN: A Steric Hindrance Model , Workshop on Desensitization of...Explosives and Propellants, Rijswijk, The Netherlands, 11-13 Nov 1991. [15] Piermarini, G. J., Block, S., Miller , P. J., Effects of Pressure on

  8. Atmospheric emission of NOx from mining explosives: A critical review

    NASA Astrophysics Data System (ADS)

    Oluwoye, Ibukun; Dlugogorski, Bogdan Z.; Gore, Jeff; Oskierski, Hans C.; Altarawneh, Mohammednoor

    2017-10-01

    High-energy materials such as emulsions, slurries and ammonium-nitrate fuel-oil (ANFO) explosives play crucial roles in mining, quarrying, tunnelling and many other infrastructure activities, because of their excellent transport and blasting properties. These explosives engender environmental concerns, due to atmospheric pollution caused by emission of dust and nitrogen oxides (NOx) from blasts, the latter characterised by the average emission factor of 5 kg (t AN explosive)-1. This first-of-its-kind review provides a concise literature account of the formation of NOx during blasting of AN-based explosives, employed in surface operations. We estimate the total NOx emission rate from AN-based explosives as 0.05 Tg (i.e., 5 × 104 t) N per annum, compared to the total global annual anthropogenic NOx emissions of 41.3 × 106 t N y-1. Although minor in the global sense, the large localised plumes from blasting exhibit high NOx concentration (500 ppm) exceeding up to 3000 times the international standards. This emission has profound consequences at mining sites and for adjacent atmospheric environment, necessitating expensive management of exclusion zones. The review describes different types of AN energetic materials for civilian applications, and summarises the essential properties and terminologies pertaining to their use. Furthermore, we recapitulate the mechanisms that lead to the formation of the reactive nitrogen species in blasting of AN-based explosives, review their implications to atmospheric air pollution, and compare the mechanisms with those experienced in other thermal and combustion operations. We also examine the mitigation approaches, including guidelines and operational-control measures. The review discusses the abatement technologies such as the formulation of new explosive mixtures, comprising secondary fuels, spin traps and other additives, in light of their effectiveness and efficiency. We conclude the review with a summary of unresolved problems

  9. Supernova explosions.

    NASA Technical Reports Server (NTRS)

    Cameron, A. G. W.

    1971-01-01

    The recent history of theoretical investigations of the supernova mechanism is considered, giving attention also to a number of nuclear physical problems which have yet to be solved in connection with the thermonuclear detonation. A variety of different processes of nucleo-synthesis are expected to occur in association with the supernova explosions. Aspects of the chemical evolution of the galaxy are discussed including the cosmic ray production of lithium, beryllium, and boron in the interstellar medium. Various hypotheses to account for the very large amount of light that comes from a supernova explosion are also examined.

  10. Explosive laser

    DOEpatents

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

    1975-09-01

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

  11. Emergent explosive synchronization in adaptive complex networks

    NASA Astrophysics Data System (ADS)

    Avalos-Gaytán, Vanesa; Almendral, Juan A.; Leyva, I.; Battiston, F.; Nicosia, V.; Latora, V.; Boccaletti, S.

    2018-04-01

    Adaptation plays a fundamental role in shaping the structure of a complex network and improving its functional fitting. Even when increasing the level of synchronization in a biological system is considered as the main driving force for adaptation, there is evidence of negative effects induced by excessive synchronization. This indicates that coherence alone cannot be enough to explain all the structural features observed in many real-world networks. In this work, we propose an adaptive network model where the dynamical evolution of the node states toward synchronization is coupled with an evolution of the link weights based on an anti-Hebbian adaptive rule, which accounts for the presence of inhibitory effects in the system. We found that the emergent networks spontaneously develop the structural conditions to sustain explosive synchronization. Our results can enlighten the shaping mechanisms at the heart of the structural and dynamical organization of some relevant biological systems, namely, brain networks, for which the emergence of explosive synchronization has been observed.

  12. Emergent explosive synchronization in adaptive complex networks.

    PubMed

    Avalos-Gaytán, Vanesa; Almendral, Juan A; Leyva, I; Battiston, F; Nicosia, V; Latora, V; Boccaletti, S

    2018-04-01

    Adaptation plays a fundamental role in shaping the structure of a complex network and improving its functional fitting. Even when increasing the level of synchronization in a biological system is considered as the main driving force for adaptation, there is evidence of negative effects induced by excessive synchronization. This indicates that coherence alone cannot be enough to explain all the structural features observed in many real-world networks. In this work, we propose an adaptive network model where the dynamical evolution of the node states toward synchronization is coupled with an evolution of the link weights based on an anti-Hebbian adaptive rule, which accounts for the presence of inhibitory effects in the system. We found that the emergent networks spontaneously develop the structural conditions to sustain explosive synchronization. Our results can enlighten the shaping mechanisms at the heart of the structural and dynamical organization of some relevant biological systems, namely, brain networks, for which the emergence of explosive synchronization has been observed.

  13. Explosive Characteristics of Carbonaceous Nanoparticles

    NASA Astrophysics Data System (ADS)

    Turkevich, Leonid; Fernback, Joseph; Dastidar, Ashok

    2013-03-01

    Explosion testing has been performed on 20 codes of carbonaceous particles. These include SWCNTs (single-walled carbon nanotubes), MWCNTs (multi-walled carbon nanotubes), CNFs (carbon nanofibers), graphene, diamond, fullerene, carbon blacks and graphites. Explosion screening was performed in a 20 L explosion chamber (ASTM E1226-10 protocol), at a (dilute) concentration of 500 g/m3, using a 5 kJ ignition source. Time traces of overpressure were recorded. Samples exhibited overpressures of 5-7 bar, and deflagration index KSt = V1/3 (dp/pt)max ~ 10 - 80 bar-m/s, which places these materials in European Dust Explosion Class St-1 (similar to cotton and wood dust). There was minimal variation between these different materials. The explosive characteristics of these carbonaceous powders are uncorrelated with particle size (BET specific surface area). Additional tests were performed on selected materials to identify minimum explosive concentration [MEC]. These materials exhibit MEC ~ 101 -102 g/m3 (lower than the MEC for coals). The concentration scans confirm that the earlier screening was performed under fuel-rich conditions (i.e. the maximum over-pressure and deflagration index exceed the screening values); e.g. the true fullerene KSt ~ 200 bar-m/s, placing it borderline St-1/St-2. Work supported through the NIOSH Nanotechnology Research Center (NTRC)

  14. 27 CFR 555.181 - Reporting of plastic explosives.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2011-04-01 2010-04-01 true 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 States...

  15. 27 CFR 555.181 - Reporting of plastic explosives.

    Code of Federal Regulations, 2010 CFR

    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 States...

  16. 27 CFR 555.181 - Reporting of plastic explosives.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2013-04-01 2013-04-01 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 States...

  17. 27 CFR 555.181 - Reporting of plastic explosives.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2014-04-01 2014-04-01 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 States...

  18. 27 CFR 555.181 - Reporting of plastic explosives.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2012-04-01 2010-04-01 true 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 States...

  19. Observational properties of SNe Ia progenitors close to the explosion

    NASA Astrophysics Data System (ADS)

    Tornambé, A.; Piersanti, L.; Raimondo, G.; Delgrande, R.

    2018-04-01

    We determine the expected signal in various observational bands of supernovae Ia progenitors just before the explosion by assuming the rotating double-degenerate scenario. Our results are valid also for all the evolutionary scenarios invoking rotation as the driving mechanism of the accretion process as well as the evolution up to the explosion. We find that the observational properties depend mainly on the mass of the exploding object, even if the angular momentum evolution after the end of the mass accretion phase and before the onset of C-burning plays a non-negligible role. Just before the explosion, the magnitude MV ranges between 9 and 11 mag, while the colour (F225W - F555W) is about -1.64 mag. The photometric properties remain constant for a few decades before the explosion. During the last few months, the luminosity decreases very rapidly. The corresponding decline in the optical bands varies from a few hundredths up to one magnitude, the exact value depending on both the white dwarf total mass and the braking efficiency at the end of the mass transfer. This feature is related to the exponentially increasing energy production, which drives the formation of a convective core rapidly extending over a large part of the exploding object. Also, a drop in the angular velocity occurs. We find that observations in the soft X band (0.5-2 keV) may be used to check if the evolution of the SNe Ia progenitors up to the explosion is driven by rotation and, hence, to discriminate among different progenitor scenarios.

  20. Method and apparatus for detecting explosives

    DOEpatents

    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.

  1. The ins and outs of terrorist bus explosions: injury profiles of on-board explosions versus explosions occurring adjacent to a bus.

    PubMed

    Golan, Ron; Soffer, Dror; Givon, Adi; Peleg, Kobi

    2014-01-01

    Terrorist explosions occurring in varying settings have been shown to lead to significantly different injury patterns among the victims, with more severe injuries generally arising in confined space attacks. Increasing numbers of terrorist attacks have been targeted at civilian buses, yet most studies focus on events in which the bomb was detonated within the bus. This study focuses on the injury patterns and hospital utilisation among casualties from explosive terrorist bus attacks with the bomb detonated either within a bus or adjacent to a bus. All patients hospitalised at six level I trauma centres and four large regional trauma centres following terrorist explosions that occurred in and adjacent to buses in Israel between November 2000 and August 2004 were reviewed. Injury severity scores (ISS) were used to assess severity. Hospital utilisation data included length of hospital stay, surgical procedures performed, and intensive care unit (ICU) admission. The study included 262 victims of 22 terrorist attacks targeted at civilian bus passengers and drivers; 171 victims were injured by an explosion within a bus (IB), and 91 were injured by an explosion adjacent to a bus (AB). Significant differences were noted between the groups, with the IB population having higher ISS scores, more primary blast injury, more urgent surgical procedures performed, and greater ICU utilisation. Both groups had percentages of nearly 20% for burn injury, had high percentages of injuries to the head/neck, and high percentages of surgical wound and burn care. Explosive terrorist attacks detonated within a bus generate more severe injuries among the casualties and require more urgent surgical and intensive level care than attacks occurring adjacent to a bus. The comparison and description of the outcomes to these terrorist attacks should aid in the preparation and response to such devastating events. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Seismic Analysis of Three Bomb Explosions in Turkey

    NASA Astrophysics Data System (ADS)

    Necmioglu, O.; Semin, K. U.; Kocak, S.; Destici, C.; Teoman, U.; Ozel, N. M.

    2016-12-01

    Seismic analysis of three vehicle-installed bomb explosions occurred on 13 March 2016 in Ankara, 12 May 2016 in Diyarbakır and 9 July 2016 in Mardin have been conducted using data from the nearest stations (LOD, DYBB and MAZI) of the Boğaziçi University - Kandilli Observatory and Earthquake Research Institute's (KOERI) seismic network and compared with low-magnitude earthquakes in similar distance based on phase readings and frequency content. Amplitude spectra has been compared through Fourier transformation and earthquake-explosion frequency discrimination has been performed using various filter bands. Time-domain and spectral analysis have been performed using Geotool software provided by CTBTO. Local magnitude (ML) values have been calculated for each explosion by removing instrument-response and adding Wood-Anderson type instrument response. Approximate amount of explosives used in these explosions have been determined using empirical methods of Koper (2002). Preliminary results indicated that 16 tons TNT equivalent explosives have been used in 12 May 2016 Diyarbakır explosion, which is very much in accordance with the media reports claiming 15 tons of TNT. Our analysis for 9 July 2016 Mardin explosion matched the reported 5 tons of explosives. Results concerning 13 March 2016 Ankara explosion indicated that approximately 1,7 ton of TNT equivalent explosives were used in the attack whereas security and intelligence reports claimed 300 kg explosives as a combination of TNT, RDX and ammonium nitrate. The overestimated results obtained in our analysis for the Ankara explosion may be related due to i) high relative effectiveness factor of the RDX component of the explosive ii) inefficiency of Koper (2002) method in lower yields (since the method was developed using explosions with yields of 3-12 tons of TNT), iii) combination of both.

  3. Light metal explosives and propellants

    DOEpatents

    Wood, Lowell L.; Ishikawa, Muriel Y.; Nuckolls, John H.; Pagoria, Phillip F.; Viecelli, James A.

    2005-04-05

    Disclosed herein are light metal explosives, pyrotechnics and propellants (LME&Ps) comprising a light metal component such as Li, B, Be or their hydrides or intermetallic compounds and alloys containing them and an oxidizer component containing a classic explosive, such as CL-20, or a non-explosive oxidizer, such as lithium perchlorate, or combinations thereof. LME&P formulations may have light metal particles and oxidizer particles ranging in size from 0.01 .mu.m to 1000 .mu.m.

  4. Explosive acceleration of plates using nonconventional explosives heavily loaded with inert and reactive materials

    NASA Astrophysics Data System (ADS)

    Loiseau, Jason; Petel, Oren; Huneault, Justin; Serge, Matthew; Frost, David; Higgins, Andrew

    2013-06-01

    The detonation behavior of high explosives containing dispersed quantities or packed beds of dense additives has been previously investigated with the observation that such systems depart from the ``gamma law'' behavior typical of homogeneous explosives due to momentum transfer and thermalization between particles and detonation products. However, the influence of this non-ideal detonation behavior on the divergence speed of plates has been far less rigorously studied and existing literature suggests that the effect of dense additives cannot be explained solely through the straightforward application of the Gurney method with energy and density averaging of the explosive. In the current study, the acceleration history and terminal velocity of aluminum flyers launched by packed beds of granular material saturated by amine-sensitized nitromethane is reported. Two experimental configurations are used to study acceleration either by a purely grazing detonation in a finite thickness slab of explosive or by a normal detonation from an effectively infinite thickness of explosive. Flyer acceleration and velocity is measured via Photonic Doppler Velocimetry. Packed beds of plastic, aluminum, glass, iron, and bismuth are considered and the data is compared to Gurney velocity predictions.

  5. Explosions of Thorne-Żytkow objects

    NASA Astrophysics Data System (ADS)

    Moriya, Takashi J.

    2018-03-01

    We propose that massive Thorne-Żytkow objects can explode. A Thorne-Żytkow object is a theoretically predicted star that has a neutron core. When nuclear reactions supporting a massive Thorne-Żytkow object terminate, a strong accretion occurs towards the central neutron core. The accretion rate is large enough to sustain a super-Eddington accretion towards the neutron core. The neutron core may collapse to a black hole after a while. A strong large-scale outflow or a jet can be launched from the super-Eddington accretion disc and the collapsing Thorne-Żytkow object can be turned into an explosion. The ejecta have about 10 M⊙ but the explosion energy depends on when the accretion is suppressed. We presume that the explosion energy could be as low as ˜1047 erg and such a low-energy explosion could be observed like a failed supernova. The maximum possible explosion energy is ˜1052 erg and such a high-energy explosion could be observed as an energetic Type II supernova or a superluminous supernova. Explosions of Thorne-Żytkow objects may provide a new path to spread lithium and other heavy elements produced through the irp process such as molybdenum in the Universe.

  6. Explosively pumped laser light

    DOEpatents

    Piltch, Martin S.; Michelotti, Roy A.

    1991-01-01

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

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Springer, H K; Glascoe, E A; Reaugh, J E

    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.more » 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.« less

  8. Explosives mimic for testing, training, and monitoring

    DOEpatents

    Reynolds, John G.; Durban, Matthew M.; Gash, Alexander E.; Grapes, Michael D.; Kelley, Ryan S.; Sullivan, Kyle T.

    2018-02-13

    Additive Manufacturing (AM) is used to make mimics for explosives. The process uses mixtures of explosives and matrices commonly used in AM. The explosives are formulated into a mixture with the matrix and printed using AM techniques and equipment. The explosive concentrations are kept less than 10% by wt. of the mixture to conform to requirements of shipping and handling.

  9. Effect of type of explosives and physical-mechanical properties of explosive rock on formation of toxic gases in atmosphere of shafts

    NASA Technical Reports Server (NTRS)

    Mindeli, E. O.; Khudyakov, M. Y.

    1981-01-01

    The quality of toxic gases formed during explosive work in underground shafts depends upon the type of explosives and the conditions of explosion. Several types of explosives and rocks were examined. All remaining conditions were maintained the same (sandy-argillaceous stemming, electrical method of explosions, diameter of blast holes, and the direct triggering of charges).

  10. Transcutaneous bilirubin levels in newborns <35 weeks' gestation.

    PubMed

    Maisels, M J; Coffey, M P; Kring, E

    2015-09-01

    In infants <35 weeks' gestation, we sought to define the transcutaneous bilirubin (TcB) levels at which a total serum bilirubin (TSB) level suggesting the need for phototherapy is unlikely to occur and a TSB measurement can, therefore, be avoided. Nursing staff performed 896 TcB measurements within 1 h of a TSB on 225 neonates 26 0/7-34 6/7 weeks' postmenstrual age (PMA). Generalized linear models were fit with generalized estimating equations (GEEs) to model the probability of having a TSB level at or above the phototherapy initiation cutpoint as a function of the TcB; these methods allow for multiple tests per infant. The mean difference between TcB and TSB measurements was <1 mg dl(-1) for each PMA category. When the TcB was at least 3 mg dl(-1) below the TSB cutpoint for phototherapy, there was a ⩾98% probability that the TSB was not at, or above, the recommended phototherapy level. The single exception to this was a phototherapy level of 6 mg dl(-1) for infants of 28 0/7-29 6/7 weeks' PMA, where a TcB of 4 mg dl(-1) below the phototherapy level (ie a TcB ⩽2 mg dl(-1)) was necessary to achieve ⩾98% probability. Our data support the use of routine TcB screening for infants 28-34 6/7 weeks' gestation. TcB screening in the neonatal intensive care unit can identify infants who require a TSB to confirm or exclude the need for phototherapy.

  11. Molecular Outflows: Explosive versus Protostellar

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zapata, Luis A.; Rodríguez, Luis F.; Palau, Aina

    2017-02-10

    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 {sup 12}CO( 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, butmore » 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.« less

  12. Fallback Accretion in Core-Collapse Supernova Explosions

    NASA Astrophysics Data System (ADS)

    Gerling-Dunsmore, Hannalore J.; Ott, Christian D.

    2015-04-01

    Core-collapse supernovae (CCSNe) are expected to result in one of two kinds remnants: neutron stars (NSs) and black holes (BHs). It is believed that if a CCSN explosion fails, a BH results, and if the explosion is successful, a NS results. This certainly is the case if there is a strong explosion that unbinds the entire stellar mantle. However, in the case of a weak or severely asymmetric explosion, a substantial quantity of material may fall back. This is commonly called fallback accretion, and it is a potential means of BH formation. We study fallback accretion in spherically-symmetric (1D) neutrino-driven CCSNe using the open-source GR1D code. We obtain explosions by artificially enchancing neutrino energy deposition and in this way also control the explosion energy. We present results on the mapping from progenitor structure and explosion energy to amount and rate of fallback accretion. This research was partially supported by NSF Award No. AST-1212170.

  13. Method for laser machining explosives and ordnance

    DOEpatents

    Muenchausen, Ross E.; Rivera, Thomas; Sanchez, John A.

    2003-05-06

    Method for laser machining explosives and related articles. A laser beam is directed at a surface portion of a mass of high explosive to melt and/or vaporize the surface portion while directing a flow of gas at the melted and/or vaporized surface portion. The gas flow sends the melted and/or vaporized explosive away from the charge of explosive that remains. The method also involves splitting the casing of a munition having an encased explosive. The method includes rotating a munition while directing a laser beam to a surface portion of the casing of an article of ordnance. While the beam melts and/or vaporizes the surface portion, a flow of gas directed at the melted and/or vaporized surface portion sends it away from the remaining portion of ordnance. After cutting through the casing, the beam then melts and/or vaporizes portions of the encased explosive and the gas stream sends the melted/vaporized explosive away from the ordnance. The beam is continued until it splits the article, after which the encased explosive, now accessible, can be removed safely for recycle or disposal.

  14. Relationship between transcutaneous bilirubin and circulating unbound bilirubin in jaundiced neonates.

    PubMed

    Letamendia-Richard, Emmanuelle; Ammar, Rafik Ben; Tridente, Ascanio; De Luca, Daniele

    2016-12-01

    Transcutaneous bilirubin (TcB) consists of the skin-deposited bilirubin. Free bilirubin represents the protein-unbound bilirubin (UB) that is able to pass into the tissues. We aimed to describe the relationship UB-TcB and study the passage of UB into the skin. We prospectively enrolled 194 neonates and we measured TcB, UB, serum bilirubin and albumin. Multiple sites TcB measurement was performed, bilirubin-albumin equilibrium constant and plasma bilirubin avidity (PBA) were calculated. TcB has a similar correlation with UB and TSB. There is a quadratic relationship between UB and TcB (R 2 =0.48; p<0.001), remaining significant (β for UB 2 =-0.8; p<0.001. β for UB=1.1; p<0.001) after adjustment for gestational age, birth weight, postnatal age and albumin (Adj-R 2 =0.72). UB contributes to the skin bilirubin deposition, as there are significant correlations between albumin and TcB (r=-0.202; p=0.01) and between PBA and ΔTcB (r=0.323; p=0.017). TcB assay does not seem to directly replace UB measurement. However, TcB and UB are linked by a quadratic relationship: UB contributes to the skin bilirubin deposition but it is not the only bilirubin species measured by transcutaneous bilirubinometry. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Explosives characterization in terahertz range

    NASA Astrophysics Data System (ADS)

    Maestrojuán, I.; Palacios, I.; Etayo, D.; Iriarte, J. C.; Teniente, J.; Ederra, I.; Gonzalo, R.

    2011-11-01

    A Thz spectral characterization of the behaviour of different explosives is presented in this paper. This characterization will be done in the frequency range from 20 GHz to 4 THz using a Teraview Spectra 3000. This system has a capacity of measuring from 20 GHz to 4 THz fed by a laser source. With the Teraview Spectra 3000 equipment will be possible to calculate the refractive index, the absorbance and other important parameters of the explosive samples. With this study it will be possible to characterize some of the most common used explosives, i.e., gun explosive, gunpowder mine, pent, TNT, RDX, etc, and it will allow to determine their electromagnetic peculiarities in order to design a future imaging system that allow detecting them in security and defense sectors.

  16. The concurrence of atmospheric rivers and explosive cyclogenesis in the North Atlantic and North Pacific basins

    NASA Astrophysics Data System (ADS)

    Eiras-Barca, Jorge; Ramos, Alexandre M.; Pinto, Joaquim G.; Trigo, Ricardo M.; Liberato, Margarida L. R.; Miguez-Macho, Gonzalo

    2018-01-01

    The explosive cyclogenesis of extratropical cyclones and the occurrence of atmospheric rivers are characteristic features of a baroclinic atmosphere, and are both closely related to extreme hydrometeorological events in the mid-latitudes, particularly on coastal areas on the western side of the continents. The potential role of atmospheric rivers in the explosive cyclone deepening has been previously analysed for selected case studies, but a general assessment from the climatological perspective is still missing. Using ERA-Interim reanalysis data for 1979-2011, we analyse the concurrence of atmospheric rivers and explosive cyclogenesis over the North Atlantic and North Pacific basins for the extended winter months (ONDJFM). Atmospheric rivers are identified for almost 80 % of explosive deepening cyclones. For non-explosive cyclones, atmospheric rivers are found only in roughly 40 % of the cases. The analysis of the time evolution of the high values of water vapour flux associated with the atmospheric river during the cyclone development phase leads us to hypothesize that the identified relationship is the fingerprint of a mechanism that raises the odds of an explosive cyclogenesis occurrence and not merely a statistical relationship. These new insights on the relationship between explosive cyclones and atmospheric rivers may be helpful to a better understanding of the associated high-impact weather events.

  17. Yield Determination of Underground and Near Surface Explosions

    NASA Astrophysics Data System (ADS)

    Pasyanos, M.

    2015-12-01

    As seismic coverage of the earth's surface continues to improve, we are faced with signals from a wide variety of explosions from various sources ranging from oil train and ordnance explosions to military and terrorist attacks, as well as underground nuclear tests. We present on a method for determining the yield of underground and near surface explosions, which should be applicable for many of these. We first review the regional envelope method that was developed for underground explosions (Pasyanos et al., 2012) and more recently modified for near surface explosions (Pasyanos and Ford, 2015). The technique models the waveform envelope templates as a product of source, propagation (geometrical spreading and attenuation), and site terms, while near surface explosions include an additional surface effect. Yields and depths are determined by comparing the observed envelopes to the templates and minimizing the misfit. We then apply the method to nuclear and chemical explosions for a range of yields, depths, and distances. We will review some results from previous work, and show new examples from ordnance explosions in Scandinavia, nuclear explosions in Eurasia, and chemical explosions in Nevada associated with the Source Physics Experiments (SPE).

  18. Portable SERS Instrument for Explosives Monitoring

    DTIC Science & Technology

    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

  19. Energetic Trend in Explosive Activity of Stromboli

    NASA Astrophysics Data System (ADS)

    Coltelli, M.; Cristaldi, A.; Mangiagli, S.; Nunnari, G.; Pecora, E.

    2003-12-01

    The typical activity of Stromboli consists of intermittent mild explosions lasting a few seconds, which take place at different vents and at variable intervals, the most common time interval being 10-20 minutes. However, the routine activity can be interrupted by more violent, paroxysmal explosions, that eject m-sized scoriaceous bombs and lava blocks to a distance of several hundreds of meters from the craters, endangering the numerous tourists that watch the spectacular activity from the volcano's summit located about two hundreds meters from the active vents. On average, 1-2 paroxysmal explosions occurred per year over the past century, but this statistic may be underestimated in absence of continuous monitoring. For this reason from summer 1996 a remote surveillance camera works on Stromboli recording continuously the volcanic activity. It is located on Pizzo Sopra la Fossa, 100 metres above the crater terrace where are the active vents. Using image analysis we seeks to identify any change of the explosive activity trend that could precede a particular eruptive event, like paroxysmal explosions, fire fountains, lava flows. The analysis include the counting of the explosions occurred at the different craters and the parameterization in classes of intensity for each explosion on the base of tephra dispersion and kinetics energy. Associating at each class a corresponding Index of energy in order to compute an heuristic value of the Average Daily Energy Released (ADER) of the explosive activity at Stromboli and plotting this value for each crater versus time, the diagram shows a cyclic behavior with max and min of explosive activity ranging from a few days to a month. Often the craters show opposite trends so when the activity decreases in a crater, increases in the other. Before every paroxysmal explosions recorded, the crater that produced the event decreased and then stopped its activity from a few days to weeks before. The other crater tried to compensate

  20. Explosion risk evaluation during production of coating powder.

    PubMed

    Li, Gang; Yuan, Chunmiao; Chen, Baozhi

    2007-10-22

    Powder coating is widely used in industry to prevent equipment corrosion. More than 600 companies produce coating powder in China, but most do not understand the explosion hazard of such products. In the present investigation the explosibility parameters of a coating powder were determined. Results showed that the coating powder is explosible, though the ignition energy is higher than those of normal dusts such as coal powder and corn starch. Based on these experimental findings, a systematic explosion protection method is proposed, with explosion isolation and explosion venting being adopted as the main protective methods.

  1. A Prospective Comparison of Transcutaneous and Serum Bilirubin Within Brief Time Intervals.

    PubMed

    Jones, Denise F; McRea, Abigail R; Knowles, James D; Lin, Feng-Chang; Burnette, Erin; Reller, Lara A; Lohr, Jacob A

    2017-10-01

    The American Academy of Pediatrics recommends screening newborns ≥35 weeks' gestation with total serum bilirubin (TSB) or transcutaneous bilirubin (TcB) to detect hyperbilirubinemia. Retrospective studies show TcB measurements strongly correlate with TSB; however, few prospective trials document this relationship. Furthermore, Dräger's newest TcB instrument, JM-105, remains unstudied in the United States. We measure TcB on foreheads and sternums of newborns using JM-105 and Bilichek devices within 30 minutes of TSB measurement. We find best overall TcB/TSB correlation with JM-105 on the sternum (mean TcB-TSB difference: -0.21 ± 1.15 mg/dL). Correlations between paired measurements for TcB on the sternum using JM-105 were 0.93 for all TSB levels (n = 178), 0.82 for TSB > 10 (n = 19), 0.69 for TSB > 12 (n = 11), and 0.52 for TSB > 15 (n = 6). TcB accuracy via JM-105 on the sternum significantly differed among races ( P < .001). For 5% of paired measurements, TcB with JM-105 on the sternum underestimated TSB by ≥2 mg/dL, and for <1% by ≥3 mg/dL.

  2. Individual heterogeneity generating explosive system network dynamics.

    PubMed

    Manrique, Pedro D; Johnson, Neil F

    2018-03-01

    Individual heterogeneity is a key characteristic of many real-world systems, from organisms to humans. However, its role in determining the system's collective dynamics is not well understood. Here we study how individual heterogeneity impacts the system network dynamics by comparing linking mechanisms that favor similar or dissimilar individuals. We find that this heterogeneity-based evolution drives an unconventional form of explosive network behavior, and it dictates how a polarized population moves toward consensus. Our model shows good agreement with data from both biological and social science domains. We conclude that individual heterogeneity likely plays a key role in the collective development of real-world networks and communities, and it cannot be ignored.

  3. Individual heterogeneity generating explosive system network dynamics

    NASA Astrophysics Data System (ADS)

    Manrique, Pedro D.; Johnson, Neil F.

    2018-03-01

    Individual heterogeneity is a key characteristic of many real-world systems, from organisms to humans. However, its role in determining the system's collective dynamics is not well understood. Here we study how individual heterogeneity impacts the system network dynamics by comparing linking mechanisms that favor similar or dissimilar individuals. We find that this heterogeneity-based evolution drives an unconventional form of explosive network behavior, and it dictates how a polarized population moves toward consensus. Our model shows good agreement with data from both biological and social science domains. We conclude that individual heterogeneity likely plays a key role in the collective development of real-world networks and communities, and it cannot be ignored.

  4. Explosive cell lysis as a mechanism for the biogenesis of bacterial membrane vesicles and biofilms

    PubMed Central

    Turnbull, Lynne; Toyofuku, Masanori; Hynen, Amelia L.; Kurosawa, Masaharu; Pessi, Gabriella; Petty, Nicola K.; Osvath, Sarah R.; Cárcamo-Oyarce, Gerardo; Gloag, Erin S.; Shimoni, Raz; Omasits, Ulrich; Ito, Satoshi; Yap, Xinhui; Monahan, Leigh G.; Cavaliere, Rosalia; Ahrens, Christian H.; Charles, Ian G.; Nomura, Nobuhiko; Eberl, Leo; Whitchurch, Cynthia B.

    2016-01-01

    Many bacteria produce extracellular and surface-associated components such as membrane vesicles (MVs), extracellular DNA and moonlighting cytosolic proteins for which the biogenesis and export pathways are not fully understood. Here we show that the explosive cell lysis of a sub-population of cells accounts for the liberation of cytosolic content in Pseudomonas aeruginosa biofilms. Super-resolution microscopy reveals that explosive cell lysis also produces shattered membrane fragments that rapidly form MVs. A prophage endolysin encoded within the R- and F-pyocin gene cluster is essential for explosive cell lysis. Endolysin-deficient mutants are defective in MV production and biofilm development, consistent with a crucial role in the biogenesis of MVs and liberation of extracellular DNA and other biofilm matrix components. Our findings reveal that explosive cell lysis, mediated through the activity of a cryptic prophage endolysin, acts as a mechanism for the production of bacterial MVs. PMID:27075392

  5. Current shunting and formation of stationary shock waves during electric explosions of metal wires in air

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ivanenkov, G. V.; Gus'kov, S. Yu.; Barishpol'tsev, D. V.

    2010-01-15

    Results of experiments on the generation of shock waves during electric explosions of fine copper and tungsten wires in air are analyzed. The generation mechanism of stationary shock wave by a plasma piston formed during the shunting breakdown of the electrode gap in the course of a wire explosion is investigated. The role of structural elements of such discharges, such as the core, corona, and wire environment, is analyzed.

  6. Identification of improvised explosives residues using physical-chemical analytical methods under real conditions after an explosion

    NASA Astrophysics Data System (ADS)

    Kotrlý, Marek; Mareš, Bohumil; Turková, Ivana; Beroun, Ivo

    2016-05-01

    Within the analysis of cases relating to the use of explosives for crimes, we have experienced a shift from using industrial explosives towards substances made in amateur and illegal way. Availability of industrial explosives is increasingly limited to a narrow sphere of subjects with a relevant permission. Thus, on the part of perpetrators, terrorists, ever greater attention is paid to illegal production of explosives that are easily made from readily available raw materials. Another alarming fact is the availability of information found on the internet. Procedures of preparation are often very simple and do not require even a deeper professional knowledge. Explosive characteristics are not actually accessible for many of these substances (detonation velocity, sensitivity, working capacity, brisance, physical and chemical stability, etc.). Therefore, a project is being implemented, which on grounds of assessment of individual information available in literature and on the internet, aiming at choosing individual areas of potentially abusable substances (e.g. mixtures of nitric acid (98%) with organic substances, mixtures nitromethane and tetranitromethane with organic substances, mixtures of chlorates and perchlorates of alkali metals with organic substances, chemically individual compounds of organic base type of perchloric acid, azides, fulminates, acetylides, picrates, styphnates of heavy metals, etc.). It is directed towards preparation of these explosives also in non-stoichiometric mixtures, conducting test explosives, determination of explosive characteristics (if they are unknown) and analysis of both primary phases and post-blast residues through available analytical techniques, such as gas and liquid chromatography with mass detection, FTIR, micro-Raman spectrometry, electron microscopy with microanalysis and Raman microspectrometry directly in SEM chamber for analysis at the level of individual microparticles. The received characteristics will be used to

  7. Fragment structure from vapor explosions during the impact of molten metal droplets into a liquid pool

    NASA Astrophysics Data System (ADS)

    Kouraytem, Nadia; Li, Er Qiang; Vakarelski, Ivan Uriev; Thoroddsen, Sigurdur

    2015-11-01

    High-speed video imaging is used in order to look at the impact of a molten metal drop falling into a liquid pool. The interaction regimes are three: film boiling, nucleate boiling or vapor explosion. Following the vapor explosion, the metal fragments and different textures are observed. It was seen that, using a tin alloy, a porous structure results whereas using a distinctive eutectic metal, Field's metal, micro beads are formed. Different parameters such as the metal type, molten metal temperature, pool surface tension and pool boiling temperature have been altered in order to assess the role they play on the explosion dynamics and the molten metal's by product.

  8. Thermodynamic States in Explosion Fields

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    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. Formore » 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.« less

  9. How Turbulence Enables Core-collapse Supernova Explosions

    NASA Astrophysics Data System (ADS)

    Mabanta, Quintin A.; Murphy, Jeremiah W.

    2018-03-01

    An important result in core-collapse supernova (CCSN) theory is that spherically symmetric, one-dimensional simulations routinely fail to explode, yet multidimensional simulations often explode. Numerical investigations suggest that turbulence eases the condition for explosion, but how it does it is not fully understood. We develop a turbulence model for neutrino-driven convection, and show that this turbulence model reduces the condition for explosions by about 30%, in concordance with multidimensional simulations. In addition, we identify which turbulent terms enable explosions. Contrary to prior suggestions, turbulent ram pressure is not the dominant factor in reducing the condition for explosion. Instead, there are many contributing factors, with ram pressure being only one of them, but the dominant factor is turbulent dissipation (TD). Primarily, TD provides extra heating, adding significant thermal pressure and reducing the condition for explosion. The source of this TD power is turbulent kinetic energy, which ultimately derives its energy from the higher potential of an unstable convective profile. Investigating a turbulence model in conjunction with an explosion condition enables insight that is difficult to glean from merely analyzing complex multidimensional simulations. An explosion condition presents a clear diagnostic to explain why stars explode, and the turbulence model allows us to explore how turbulence enables explosion. Although we find that TD is a significant contributor to successful supernova explosions, it is important to note that this work is to some extent qualitative. Therefore, we suggest ways to further verify and validate our predictions with multidimensional simulations.

  10. Surface waves generated by shallow underwater explosions

    NASA Technical Reports Server (NTRS)

    Falade, A.; Holt, M.

    1978-01-01

    Surface water waves generated by surface and near surface point explosions are calculated. Taking the impulse distribution imparted at the water surface by the explosion as the overriding mechanism for transferring energy of the explosive to surface wave motion, the linearized theory of Kranzer and Keller is used to obtain the wave displacement in the far field. The impulse distribution is obtained by integrating the pressure wave over an appropriate time interval on a horizontal surface just beneath the undisturbed water surface. For surface explosions, a modified form of the similarity method first used by Collins and Holt is used to obtain the flow field. In the case of submerged explosions, the flow field is estimated by making necessary modifications to Sedov's similarity solution to account for the venting that accompanies the interaction of the leading (blast) wave with the ocean surface. Surface waves generated by a charge at six depths of placement (0.15 m, 0.30 m, 0.61 m, 0.91 m, 1.37 m, 3.05 m) are considered in addition to surface explosions. The results seem to support the existence of an upper critical depth phenomenon (of the type already established for chemical explosions) for point (nuclear) explosions.

  11. 40 CFR 265.382 - Open burning; waste explosives.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 27 2013-07-01 2013-07-01 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...

  12. 40 CFR 265.382 - Open burning; waste explosives.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 26 2014-07-01 2014-07-01 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...

  13. 40 CFR 265.382 - Open burning; waste explosives.

    Code of Federal Regulations, 2010 CFR

    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...

  14. 40 CFR 265.382 - Open burning; waste explosives.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 27 2012-07-01 2012-07-01 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...

  15. 40 CFR 265.382 - Open burning; waste explosives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 26 2011-07-01 2011-07-01 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...

  16. 33 CFR 401.68 - Explosives Permission Letter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... following cases: (1) For all vessels carrying any quantity of explosives with a mass explosive risk, up to a... and up to a maximum of 50 tonnes of explosives that do not explode en masse (IMO Class 1, Division 1.2...

  17. 29 CFR 1926.902 - Surface transportation of explosives.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Surface transportation of explosives. 1926.902 Section 1926... Explosives § 1926.902 Surface transportation of explosives. (a) Transportation of explosives shall meet the provisions of Department of Transportation regulations contained in 46 CFR parts 146-149, Water Carriers; 49...

  18. 29 CFR 1926.902 - Surface transportation of explosives.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Surface transportation of explosives. 1926.902 Section 1926... Explosives § 1926.902 Surface transportation of explosives. (a) Transportation of explosives shall meet the provisions of Department of Transportation regulations contained in 46 CFR parts 146-149, Water Carriers; 49...

  19. 29 CFR 1926.902 - Surface transportation of explosives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Surface transportation of explosives. 1926.902 Section 1926... Explosives § 1926.902 Surface transportation of explosives. (a) Transportation of explosives shall meet the provisions of Department of Transportation regulations contained in 46 CFR parts 146-149, Water Carriers; 49...

  20. 29 CFR 1926.902 - Surface transportation of explosives.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Surface transportation of explosives. 1926.902 Section 1926... Explosives § 1926.902 Surface transportation of explosives. (a) Transportation of explosives shall meet the provisions of Department of Transportation regulations contained in 46 CFR parts 146-149, Water Carriers; 49...

  1. Visible-Near Infrared Imaging Spectrometer Data of Explosion Craters

    NASA Technical Reports Server (NTRS)

    Farr, T. G.

    2005-01-01

    In a continuing study to capture a realistic terrain applicable to studies of cratering processes and landing hazards on Mars, we have obtained new high resolution visible-near infrared images of several explosion craters at the Nevada Test Site. We used the Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) to obtain images in 224 spectral bands from 0.4-2.5 microns [1]. The main craters that were imaged were Sedan, Scooter, Schooner, Buggy, and Danny Boy [2]. The 390 m diameter Sedan crater, located on Yucca Flat, is the largest and freshest explosion crater on Earth that was formed under conditions similar to hypervelocity impact cratering. As such, it is effectively pristine, having been formed in 1962 as a result of the detonation of a 104 kiloton thermonuclear device, buried at the appropriate equivalent depth of burst required to make a "simple" crater [2]. Sedan was formed in alluvium of mixed lithology [3] and subsequently studied using a variety of field-based methods. Nearby secondary craters were also formed at the time and were also imaged by AVIRIS. Adjacent to Sedan and also in alluvium is Scooter, about 90 m in diameter and formed by a high-explosive event. Schooner (240 m) and Danny Boy (80 m, Fig. 1) craters were also important targets for AVIRIS as they were excavated in hard welded tuff and basaltic andesite, respectively [3, 4]. This variation in targets will allow the study of ejecta patterns, compositional modifications due to the explosions, and the role of craters as subsurface probes.

  2. 30 CFR 56.6903 - Burning explosive material.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Burning explosive material. 56.6903 Section 56... Requirements § 56.6903 Burning explosive material. If explosive material is suspected of burning at the blast... after the burning or suspected burning has stopped. ...

  3. 30 CFR 56.6903 - Burning explosive material.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Burning explosive material. 56.6903 Section 56... Requirements § 56.6903 Burning explosive material. If explosive material is suspected of burning at the blast... after the burning or suspected burning has stopped. ...

  4. 30 CFR 56.6903 - Burning explosive material.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Burning explosive material. 56.6903 Section 56... Requirements § 56.6903 Burning explosive material. If explosive material is suspected of burning at the blast... after the burning or suspected burning has stopped. ...

  5. 30 CFR 56.6903 - Burning explosive material.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Burning explosive material. 56.6903 Section 56... Requirements § 56.6903 Burning explosive material. If explosive material is suspected of burning at the blast... after the burning or suspected burning has stopped. ...

  6. 30 CFR 56.6903 - Burning explosive material.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Burning explosive material. 56.6903 Section 56... Requirements § 56.6903 Burning explosive material. If explosive material is suspected of burning at the blast... after the burning or suspected burning has stopped. ...

  7. Explosives Detection: Exploitation of the Physical Signatures

    NASA Astrophysics Data System (ADS)

    Atkinson, David

    2010-10-01

    Explosives based terrorism is an ongoing threat that is evolving with respect to implementation, configuration and materials used. There are a variety of devices designed to detect explosive devices, however, each technology has limitations and operational constraints. A full understanding of the signatures available for detection coupled with the array of detection choices can be used to develop a conceptual model of an explosives screening operation. Physics based sensors provide a robust approach to explosives detection, typically through the identification of anomalies, and are currently used for screening in airports around the world. The next generation of detectors for explosives detection will need to be more sensitive and selective, as well as integrate seamlessly with devices focused on chemical signatures. An appreciation for the details of the physical signature exploitation in cluttered environments with time, space, and privacy constraints is necessary for effective explosives screening of people, luggage, cargo, and vehicles.

  8. Evaluation of BiliCare™ transcutaneous bilirubin device in Japanese newborns.

    PubMed

    Yamana, Keiji; Morioka, Ichiro; Kurokawa, Daisuke; Fukushima, Sachiyo; Nishida, Kosuke; Ohyama, Shohei; Nishimura, Noriyuki; Nozu, Kandai; Taniguchi-Ikeda, Mariko; Nagase, Hiroaki; Fujioka, Kazumichi; Iwatani, Sota; Nakamura, Hajime; Iijima, Kazumoto

    2017-10-01

    Non-invasive transcutaneous bilirubin (TcB) monitoring has been widely used to screen for hyperbilirubinemia. TcB measured using the recently developed BiliCare™ system, however, has not been fully evaluated. One hundred and seven TcB measurements were obtained from 82 Japanese newborns ≥35 weeks' gestational age within 2 weeks after birth. Measurements were taken at the scaphoid fossa, conchal cavity, and lobe of the ear using BiliCare. BiliCare TcB were compared with total serum bilirubin (TB) and TcB obtained using another bilirubinometer (JM-105™). Transcutaneous bilirubin measured at all three sites significantly correlated with TB (r = 0.91, 0.93, and 0.93 at the scaphoid fossa, conchal cavity, and lobe, respectively). The mean differences were 0.1, -0.3, and 3.6 at the scaphoid fossa, conchal cavity, and lobe, respectively. BiliCare TcB at the scaphoid fossa significantly correlated with that using the JM-105 (r = 0.91). The mean difference was 0.0. BiliCare, however, produced a significantly higher and lower TcB than the JM-105 for TB <7 and ≥15 mg/dL, respectively. Transcutaneous bilirubin measurements taken at the scaphoid fossa or conchal cavity using BiliCare were more reliable than those at the earlobe. BiliCare TcB differed from those of the JM-105, for TB <7 or ≥15 mg/dL. © 2017 Japan Pediatric Society.

  9. Determination of JWL Parameters for Non-Ideal Explosive

    NASA Astrophysics Data System (ADS)

    Hamashima, H.; Kato, Y.; Itoh, S.

    2004-07-01

    JWL equation of state is widely used in numerical simulation of detonation phenomena. JWL parameters are determined by cylinder test. Detonation characteristics of non-ideal explosive depend strongly on confinement, and JWL parameters determined by cylinder test do not represent the state of detonation products in many applications. We developed a method to determine JWL parameters from the underwater explosion test. JWL parameters were determined through a method of characteristics applied to the configuration of the underwater shock waves of cylindrical explosives. The numerical results obtained using JWL parameters determined by the underwater explosion test and those obtained using JWL parameters determined by cylinder test were compared with experimental results for typical non-ideal explosive; emulsion explosive. Good agreement was confirmed between the results obtained using JWL parameters determined by the underwater explosion test and experimental results.

  10. Concepts of Ideal and Nonideal Explosives.

    DTIC Science & Technology

    1981-12-01

    Akst and J. Hershkowitz, "Explosive Performance Modification by Cosolidifaction of Ammonium Nitrate with Fuels ," Technical Report 4987, Picatinny...explosives Equations of state Diameter effect Ammonium nitrate 20. ASSrRACr (ca’mes r w re t N netwezy ad identity by block number) The purpose of...this report is to stimulate discussion on the nonideality of ammonium nitrate and its composite explosives. The concept of ideal and non- ideal

  11. Regional Seismic Methods of Identifying Explosions

    NASA Astrophysics Data System (ADS)

    Walter, W. R.; Ford, S. R.; Pasyanos, M.; Pyle, M. L.; Hauk, T. F.

    2013-12-01

    A lesson from the 2006, 2009 and 2013 DPRK declared nuclear explosion Ms:mb observations is that our historic collection of data may not be representative of future nuclear test signatures (e.g. Selby et al., 2012). To have confidence in identifying future explosions amongst the background of other seismic signals, we need to put our empirical methods on a firmer physical footing. Here we review the two of the main identification methods: 1) P/S ratios and 2) Moment Tensor techniques, which can be applied at the regional distance (200-1600 km) to very small events, improving nuclear explosion monitoring and confidence in verifying compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Amplitude ratios of seismic P-to-S waves at sufficiently high frequencies (~>2 Hz) can identify explosions among a background of natural earthquakes (e.g. Walter et al., 1995). However the physical basis for the generation of explosion S-waves, and therefore the predictability of this P/S technique as a function of event properties such as size, depth, geology and path, remains incompletely understood. Calculated intermediate period (10-100s) waveforms from regional 1-D models can match data and provide moment tensor results that separate explosions from earthquakes and cavity collapses (e.g. Ford et al. 2009). However it has long been observed that some nuclear tests produce large Love waves and reversed Rayleigh waves that complicate moment tensor modeling. Again the physical basis for the generation of these effects from explosions remains incompletely understood. We are re-examining regional seismic data from a variety of nuclear test sites including the DPRK and the former Nevada Test Site (now the Nevada National Security Site (NNSS)). Newer relative amplitude techniques can be employed to better quantify differences between explosions and used to understand those differences in term of depth, media and other properties. We are also making use of the Source Physics

  12. Explosives for Lunar Seismic Profiling Experiment (LSPE)

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Explosive charges of various sizes were investigated for use in lunar seismic studies. Program logistics, and the specifications for procurement of bulk explosives are described. The differential analysis, thermal properties, and detonation velocity measurements on HNS/Teflon 7C 90/10 are reported along with the field tests of the hardware. It is concluded that nearly all large explosive charges crack after fabrication, from aging or thermal shock. The cracks do not affect the safety, or reliability of the explosives.

  13. High-explosive driven crowbar switch

    DOEpatents

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

    1976-01-13

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

  14. Donor free radical explosive composition

    DOEpatents

    Walker, Franklin E. [15 Way Points Rd., Danville, CA 94526; Wasley, Richard J. [4290 Colgate Way, Livermore, CA 94550

    1980-04-01

    An improved explosive composition is disclosed and comprises a major portion of an explosive having a detonation velocity between about 1500 and 10,000 meters per second and a minor amount of a donor additive comprising an organic compound or mixture of organic compounds capable of releasing low molecular weight free radicals or ions under mechanical or electrical shock conditions and which is not an explosive, or an inorganic compound or mixture of inorganic compounds capable of releasing low molecular weight free radicals or ions under mechanical or electrical shock conditions and selected from ammonium or alkali metal persulfates.

  15. Novel high explosive compositions

    DOEpatents

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

    1968-04-16

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

  16. Eigenvalue Detonation of Combined Effects Aluminized Explosives

    NASA Astrophysics Data System (ADS)

    Capellos, Christos; Baker, Ernest; Balas, Wendy; Nicolich, Steven; Stiel, Leonard

    2007-06-01

    This paper reports on the development of theory and performance for recently developed combined effects aluminized explosives. Traditional high energy explosives used for metal pushing incorporate high loading percentages of HMX or RDX, whereas blast explosives incorporate some percentage of aluminum. However, the high blast explosives produce increased blast energies, with reduced metal pushing capability due to late time aluminum reaction. Metal pushing capability refers to the early volume expansion work produced during the first few volume expansions associated with cylinder wall velocities and Gurney energies. Our Recently developed combined effects aluminized explosives (PAX-29C, PAX-30, PAX-42) are capable of achieving excellent metal pushing and high blast energies. Traditional Chapman-Jouguet detonation theory does not explain the observed detonation states achieved by these combined effects explosives. This work demonstrates, with the use of cylinder expansion data and thermochemical code calculations (JAGUAR and CHEETAH), that eigenvalue detonation theory explains the observed behavior.

  17. Separation of cis and trans geometric isomers by Coulomb explosion imaging

    NASA Astrophysics Data System (ADS)

    Ablikim, Utuq; Kaderiya, B.; Kumarapan, V.; Rudenko, A.; Rolles, D.; Bomme, C.; Savelyev, E.; Xiong, H.; Berrah, N.; Kilcoyne, D.

    2016-05-01

    Isomers, i.e. molecules with the same chemical formula but different chemical structure, play an important role in many biological processes. Recently, it was shown that it is possible to identify different isomers of a chiral molecule by Coulomb explosion imaging. Here, we show that by imaging the Coulomb explosion of C2 H2 Br2 molecules after inner-shell photoionization, we are able to separate a mixture of cis and trans structures using the momentum correlation between ionic fragments measured in coincidence. Furthermore, we used this capability to investigate the isomer-selective photoionization and fragmentation dynamics of C2 H2 Br2 after Br (3d) ionization. Coulomb explosion simulation results for momentum correlation as well as kinetic energies match closely the experimental results. This project is supported by the DOE, Office of Science, BES, Division of Chemical, Geological and Biological Sciences under Award Number DE-FG02-86ER13491 (U.A., B.K., V.K., A.R., D.R.) and Award Number DE-SC0012376 (H.X., N.B.).

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

    NASA Astrophysics Data System (ADS)

    Balakrishnan, Kaushik

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

  19. Parameterization of strombolian explosions: constraint from simultaneous physical and geophysical measurements (Invited)

    NASA Astrophysics Data System (ADS)

    gurioli, L.; Harris, A. J.

    2013-12-01

    Stromboli, and other volcanoes like it, are to plot in the strombolian fields of deposit-based classifications. We also quenched a number of bombs soon explosion at Stromboli. This enabled us to quantify the degassing history and rheology of the magma(s) resident in the shallow, near-surface, system. The different textural facies observed in these bombs showed that fresh magma, mingled with partially or completely degassed, oxidized, re-crystallized, evolved and high viscosity magma, was ejected. The degassed magma appears to sit at the top of the conduit, playing only a passive role in the explosive process. Our best model, is that the degassed, oxidized magma forms a plug, or rheologically defined layer, at the top of the conduit, through which the fresh magma bursts. Integration of geophysical measurements with sample analyses, indicates that popular (bubble-bursting) models may not fit this case, thus also changeling the model-based definition of this eruption type.

  20. 7 CFR 502.13 - Weapons and explosives.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Weapons and explosives. 502.13 Section 502.13....13 Weapons and explosives. No person while in or on BARC property shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except as officially authorized for...

  1. 36 CFR 520.15 - Weapons and explosives.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Weapons and explosives. 520... Weapons and explosives. No person while on the premises shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except for official purposes, nor shall any person...

  2. 36 CFR 504.14 - Weapons and explosives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Weapons and explosives. 504... GOVERNING SMITHSONIAN INSTITUTION BUILDINGS AND GROUNDS § 504.14 Weapons and explosives. No person while on the premises shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or...

  3. 36 CFR 520.15 - Weapons and explosives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Weapons and explosives. 520... Weapons and explosives. No person while on the premises shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except for official purposes, nor shall any person...

  4. 36 CFR 504.14 - Weapons and explosives.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Weapons and explosives. 504... GOVERNING SMITHSONIAN INSTITUTION BUILDINGS AND GROUNDS § 504.14 Weapons and explosives. No person while on the premises shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or...

  5. 7 CFR 502.13 - Weapons and explosives.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Weapons and explosives. 502.13 Section 502.13....13 Weapons and explosives. No person while in or on BARC property shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except as officially authorized for...

  6. 36 CFR 520.15 - Weapons and explosives.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Weapons and explosives. 520... Weapons and explosives. No person while on the premises shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except for official purposes, nor shall any person...

  7. 7 CFR 502.13 - Weapons and explosives.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 6 2012-01-01 2012-01-01 false Weapons and explosives. 502.13 Section 502.13....13 Weapons and explosives. No person while in or on BARC property shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except as officially authorized for...

  8. 36 CFR 504.14 - Weapons and explosives.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Weapons and explosives. 504... GOVERNING SMITHSONIAN INSTITUTION BUILDINGS AND GROUNDS § 504.14 Weapons and explosives. No person while on the premises shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or...

  9. 31 CFR 700.11 - Weapons and explosives.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Weapons and explosives. 700.11... FEDERAL LAW ENFORCEMENT TRAINING CENTER (FLETC) BUILDINGS AND GROUNDS § 700.11 Weapons and explosives. No person, while on the property, shall carry firearms, other dangerous or deadly weapons, or explosives...

  10. 7 CFR 502.13 - Weapons and explosives.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Weapons and explosives. 502.13 Section 502.13....13 Weapons and explosives. No person while in or on BARC property shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except as officially authorized for...

  11. 36 CFR 520.15 - Weapons and explosives.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Weapons and explosives. 520... Weapons and explosives. No person while on the premises shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except for official purposes, nor shall any person...

  12. 7 CFR 502.13 - Weapons and explosives.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Weapons and explosives. 502.13 Section 502.13....13 Weapons and explosives. No person while in or on BARC property shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except as officially authorized for...

  13. 40 CFR 258.23 - Explosive gases control.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Explosive gases control. 258.23... FOR MUNICIPAL SOLID WASTE LANDFILLS Operating Criteria § 258.23 Explosive gases control. (a) Owners or... facility does not exceed 25 percent of the lower explosive limit for methane in facility structures...

  14. 40 CFR 258.23 - Explosive gases control.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Explosive gases control. 258.23... FOR MUNICIPAL SOLID WASTE LANDFILLS Operating Criteria § 258.23 Explosive gases control. (a) Owners or... facility does not exceed 25 percent of the lower explosive limit for methane in facility structures...

  15. 30 CFR 57.6903 - Burning explosive material.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Burning explosive material. 57.6903 Section 57... General Requirements-Surface and Underground § 57.6903 Burning explosive material. If explosive material is suspected of burning at the blast site, persons shall be evacuated from the endangered area and...

  16. 30 CFR 57.6903 - Burning explosive material.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Burning explosive material. 57.6903 Section 57... General Requirements-Surface and Underground § 57.6903 Burning explosive material. If explosive material is suspected of burning at the blast site, persons shall be evacuated from the endangered area and...

  17. 30 CFR 57.6903 - Burning explosive material.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Burning explosive material. 57.6903 Section 57... General Requirements-Surface and Underground § 57.6903 Burning explosive material. If explosive material is suspected of burning at the blast site, persons shall be evacuated from the endangered area and...

  18. 30 CFR 57.6903 - Burning explosive material.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Burning explosive material. 57.6903 Section 57... General Requirements-Surface and Underground § 57.6903 Burning explosive material. If explosive material is suspected of burning at the blast site, persons shall be evacuated from the endangered area and...

  19. 30 CFR 57.6903 - Burning explosive material.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Burning explosive material. 57.6903 Section 57... General Requirements-Surface and Underground § 57.6903 Burning explosive material. If explosive material is suspected of burning at the blast site, persons shall be evacuated from the endangered area and...

  20. Explosive Leidenfrost droplets

    NASA Astrophysics Data System (ADS)

    Colinet, Pierre; Moreau, Florian; Dorbolo, Stéphane

    2017-11-01

    We show that Leidenfrost droplets made of an aqueous solution of surfactant undergo a violent explosion in a wide range of initial volumes and concentrations. This unexpected behavior turns out to be triggered by the formation of a gel-like shell, followed by a sharp temperature increase. Comparing a simple model of the radial surfactant distribution inside a spherical droplet with experiments allows highlighting the existence of a critical surface concentration for the shell to form. The temperature rise (attributed to boiling point elevation with surface concentration) is a key feature leading to the explosion, instead of the implosion (buckling) scenario reported by other authors. Indeed, under some conditions, this temperature increase is shown to be sufficient to trigger nucleation and growth of vapor bubbles in the highly superheated liquid bulk, stretching the surrounding elastic shell up to its rupture limit. The successive timescales characterizing this explosion sequence are also discussed. Funding sources: F.R.S. - FNRS (ODILE and DITRASOL projects, RD and SRA positions of P. Colinet and S. Dorbolo), BELSPO (IAP 7/38 MicroMAST project).

  1. Explosive Spot Joining of Metals

    NASA Technical Reports Server (NTRS)

    Bement, Laurence J. (Inventor); Perry, Ronnie B. (Inventor)

    1997-01-01

    The invention is an apparatus and method for wire splicing using an explosive joining process. The apparatus consists of a prebend, U-shaped strap of metal that slides over prepositioned wires. A standoff means separates the wires from the strap before joining. An adhesive means holds two ribbon explosives in position centered over the U-shaped strap. A detonating means connects to the ribbon explosives. The process involves spreading strands of each wire to be joined into a flat plane. The process then requires alternating each strand in alignment to form a mesh-like arrangement with an overlapped area. The strap slides over the strands of the wires. and the standoff means is positioned between the two surfaces. The detonating means then initiates the ribbon explosives that drive the strap to accomplish a high velocity. angular collision between the mating surfaces. This collision creates surface melts and collision bonding resulting in electron-sharing linkups.

  2. The challenge of improvised explosives

    DOE PAGES

    Maienschein, Jon L.

    2012-06-14

    Energetic materials have been developed for decades, and indeed centuries, with a common set of goals in mind. Performance (as a detonating explosive, a propellant, or a pyrotechnic) has always been key, equally important have been the attributes of safety, stability, and reproducibility. Research and development with those goals has led to the set of energetic materials commonly used today. In the past few decades, the adoption and use of improvised explosives in attacks by terrorists or third-world parties has led to many questions about these materials, e.g., how they may be made, what threat they pose to the intendedmore » target, how to handle them safely, and how to detect them. The unfortunate advent of improvised explosives has opened the door for research into these materials, and there are active programs in many countries. I will discuss issues and opportunities facing research into improvised explosives.« less

  3. Micro-explosion of compound drops

    NASA Astrophysics Data System (ADS)

    Chen, Chun-Kuei; Lin, Ta-Hui

    2014-08-01

    Introducing water into spray combustion systems, by either water-in-oil emulsification or supplementary water injection, is one of the major techniques for combustion improvement and NOx reduction. Plentiful researches are available on combustion of water-in-oil emulsion fuel drops. The emulsified liquid is a heterogeneous mixture of immiscible liquids. One component forms the continuous phase and the other component forms the discrete phase. The discrete phase consists of globules of the one fluid that are suspended in the continuous phase fluid. Water-in-oil emulsions are commonly considered for combustion applications because emulsions can result in micro-explosion, thereby reducing the average drop diameter to enhance liquid vaporization, and suppressing the formation of soot and NOx. However, the water addition generally does not exceed about 20% for smooth engine operations[!, 21. The combustion characteristics and micro-explosion of emulsion drop were studied by many researchers. The micro-explosion of water in fuel emulsion drops was caused by very fast growth of superheated water vapor bubbles, its superheat limits must be lower than the boiling point temperature of the fuel. These bubbles were primarily governed by the pressure difference between the superheated vapor and the liquid, and by the inertia imparted to the liquid by the motion of the bubble surface[3 6 In this study, we used a coaxial nozzle to generation the multi-component drop. The different type of water-in-oil fuel drops called the compound drops. Unlike an emulsion drop, a compound drop consists of a water core and a fuel shell, which can originate from the phase separation of emulsion[7, 81 or a water drop colliding with a fuel drop[9, 101 Burning and micro-explosion of compound drops have been found to be distinct from those of emulsion drops[9-111 Wang et al.[9 , 101 studied the combustion characteristics of collision merged alkane-water drops. The merged drops appeared in adhesive

  4. 31 CFR 700.11 - Weapons and explosives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Weapons and explosives. 700.11 Section... ENFORCEMENT TRAINING CENTER (FLETC) BUILDINGS AND GROUNDS § 700.11 Weapons and explosives. No person, while on the property, shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or...

  5. 31 CFR 700.11 - Weapons and explosives.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Weapons and explosives. 700.11 Section... ENFORCEMENT TRAINING CENTER (FLETC) BUILDINGS AND GROUNDS § 700.11 Weapons and explosives. No person, while on the property, shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or...

  6. 31 CFR 91.13 - Weapons and explosives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance: Treasury 1 2011-07-01 2011-07-01 false Weapons and explosives. 91.13 Section... GROUNDS § 91.13 Weapons and explosives. No person while on the property shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except for official purposes. ...

  7. 31 CFR 700.11 - Weapons and explosives.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Weapons and explosives. 700.11 Section... ENFORCEMENT TRAINING CENTER (FLETC) BUILDINGS AND GROUNDS § 700.11 Weapons and explosives. No person, while on the property, shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or...

  8. 31 CFR 91.13 - Weapons and explosives.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance: Treasury 1 2012-07-01 2012-07-01 false Weapons and explosives. 91.13 Section... GROUNDS § 91.13 Weapons and explosives. No person while on the property shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except for official purposes. ...

  9. 31 CFR 91.13 - Weapons and explosives.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance: Treasury 1 2014-07-01 2014-07-01 false Weapons and explosives. 91.13 Section... GROUNDS § 91.13 Weapons and explosives. No person while on the property shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except for official purposes. ...

  10. 31 CFR 91.13 - Weapons and explosives.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance: Treasury 1 2013-07-01 2013-07-01 false Weapons and explosives. 91.13 Section... GROUNDS § 91.13 Weapons and explosives. No person while on the property shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except for official purposes. ...

  11. 31 CFR 700.11 - Weapons and explosives.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Weapons and explosives. 700.11 Section... ENFORCEMENT TRAINING CENTER (FLETC) BUILDINGS AND GROUNDS § 700.11 Weapons and explosives. No person, while on the property, shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or...

  12. 40 CFR 258.23 - Explosive gases control.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Explosive gases control. 258.23 Section... MUNICIPAL SOLID WASTE LANDFILLS Operating Criteria § 258.23 Explosive gases control. (a) Owners or operators... does not exceed 25 percent of the lower explosive limit for methane in facility structures (excluding...

  13. Ecotoxicology of Explosives

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Efroymson, Rebecca Ann; Giffen, Neil R; Morrill, Valerie

    Managing sites contaminated with munitions constituents is an international challenge. Although the choice of approach and the use of Ecological Risk Assessment (ERA) tools may vary from country to country, the assurance of quality and the direction of ecotoxicological research are universally recognized as shared concerns. Drawing on a multidisciplinary team of contributors, 'Ecotoxicology of Explosives' provides comprehensive and critical reviews available to date on fate, transport, and effects of explosives. The book delineates the state of the science of the ecotoxicology of explosives, past, present, and recently developed. It reviews the accessible fate and ecotoxicological data for energetic materialsmore » (EMs) and the methods for their development. The chapters characterize the fate of explosives in the environment, then provide information on their ecological effects in key environmental media, including aquatic, sedimentary, and terrestrial habitats. The book also discusses approaches for assembling these lines of evidence for risk assessment purposes. The chapter authors have critically examined the peer-reviewed literature to identify and prioritize the knowledge gaps and to recommend future areas of research. The editors include a review of the genotoxic effects of the EMs and the cellular and molecular mechanisms underlying the toxicity of these chemicals. They also discuss the transport, transformation, and degradation pathways of these chemicals in the environment that underlie the potential hazardous impact and bioaccumulation of EMs in different terrestrial and aquatic ecological receptors. This information translates into practical applications for the environmental risk assessment of EM-contaminated sites and into recommendations for the sustainable use of defense installations.« less

  14. Dynamic Fracture Behavior of Plastic-Bonded Explosives

    NASA Astrophysics Data System (ADS)

    Fu, Hua; Li, Jun-Ling; Tan, Duo-Wang; Ifp, Caep Team

    2011-06-01

    Plastic-Bonded Explosives (PBX) are used as important energetic materials in nuclear or conventional weapons. Arms Warhead in the service process and the ballistic phase, may experience complex process such as long pulse and higher loading, compresson, tension and reciprocating compression - tension, friction with the projectile shell, which would lead to explosive deformation and fracture.And the dynamic deformation and fracture behavior of PBX subsequently affect reaction characteristics and initiation mechanism in explosives, then having influence on explosives safety. The dynamic fracure behavior of PBX are generally complex and not well studied or understood. In this paper, the dynamic fracture of explosives are conducted using a Kolsky bar. The Brazilian test, also known as a indirect tensile test or splitting test, is chosen as the test method. Tensile strength under different strain rates are obtained using quartz crystal embedded in rod end. The dynamic deformation and fracture process are captured in real-time by high-speed digital camera, and the displacement and strain fields distribution before specimen fracture are obtained by digital correlation method. Considering the non-uniform microstructure of explosives,the dynamic fracture behavior of explosive are simulated by discrete element method, the simulation results can reproduce the deformation and fracture process in Brazilian test using a maximum tensile strain criterion.

  15. 7 CFR 503.13 - Weapons and explosives.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Weapons and explosives. 503.13 Section 503.13... OF AGRICULTURE CONDUCT ON PLUM ISLAND ANIMAL DISEASE CENTER § 503.13 Weapons and explosives. No person while in or on the PIADC shall carry firearms or other dangerous or deadly weapons or explosives...

  16. 7 CFR 503.13 - Weapons and explosives.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 6 2012-01-01 2012-01-01 false Weapons and explosives. 503.13 Section 503.13... OF AGRICULTURE CONDUCT ON PLUM ISLAND ANIMAL DISEASE CENTER § 503.13 Weapons and explosives. No person while in or on the PIADC shall carry firearms or other dangerous or deadly weapons or explosives...

  17. 46 CFR 386.23 - Weapons and explosives.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false Weapons and explosives. 386.23 Section 386.23 Shipping... AND GROUNDS AT THE UNITED STATES MERCHANT MARINE ACADEMY § 386.23 Weapons and explosives. No person shall carry or possess firearms, other dangerous or deadly weapons or parts thereof, explosives or items...

  18. 46 CFR 386.23 - Weapons and explosives.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Weapons and explosives. 386.23 Section 386.23 Shipping... AND GROUNDS AT THE UNITED STATES MERCHANT MARINE ACADEMY § 386.23 Weapons and explosives. No person shall carry or possess firearms, other dangerous or deadly weapons or parts thereof, explosives or items...

  19. 7 CFR 503.13 - Weapons and explosives.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Weapons and explosives. 503.13 Section 503.13... OF AGRICULTURE CONDUCT ON PLUM ISLAND ANIMAL DISEASE CENTER § 503.13 Weapons and explosives. No person while in or on the PIADC shall carry firearms or other dangerous or deadly weapons or explosives...

  20. 7 CFR 503.13 - Weapons and explosives.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Weapons and explosives. 503.13 Section 503.13... OF AGRICULTURE CONDUCT ON PLUM ISLAND ANIMAL DISEASE CENTER § 503.13 Weapons and explosives. No person while in or on the PIADC shall carry firearms or other dangerous or deadly weapons or explosives...

  1. 46 CFR 386.23 - Weapons and explosives.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Weapons and explosives. 386.23 Section 386.23 Shipping... AND GROUNDS AT THE UNITED STATES MERCHANT MARINE ACADEMY § 386.23 Weapons and explosives. No person shall carry or possess firearms, other dangerous or deadly weapons or parts thereof, explosives or items...

  2. 7 CFR 503.13 - Weapons and explosives.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Weapons and explosives. 503.13 Section 503.13... OF AGRICULTURE CONDUCT ON PLUM ISLAND ANIMAL DISEASE CENTER § 503.13 Weapons and explosives. No person while in or on the PIADC shall carry firearms or other dangerous or deadly weapons or explosives...

  3. 46 CFR 386.23 - Weapons and explosives.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Weapons and explosives. 386.23 Section 386.23 Shipping... AND GROUNDS AT THE UNITED STATES MERCHANT MARINE ACADEMY § 386.23 Weapons and explosives. No person shall carry or possess firearms, other dangerous or deadly weapons or parts thereof, explosives or items...

  4. Explosion probability of unexploded ordnance: expert beliefs.

    PubMed

    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

  5. Wireless sensor for detecting explosive material

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lamberti, Vincent E; Howell, Jr., Layton N; Mee, David K

    Disclosed is a sensor for detecting explosive devices. The sensor includes a ferromagnetic metal and a molecular recognition reagent coupled to the ferromagnetic metal. The molecular recognition reagent is operable to expand upon absorption of vapor from an explosive material such that the molecular recognition reagent changes a tensile stress upon the ferromagnetic metal. The explosive device is detected based on changes in the magnetic switching characteristics of the ferromagnetic metal caused by the tensile stress.

  6. Supernova simulations from a 3D progenitor model - Impact of perturbations and evolution of explosion properties

    NASA Astrophysics Data System (ADS)

    Müller, Bernhard; Melson, Tobias; Heger, Alexander; Janka, Hans-Thomas

    2017-11-01

    We study the impact of large-scale perturbations from convective shell burning on the core-collapse supernova explosion mechanism using 3D multigroup neutrino hydrodynamics simulations of an 18M⊙ progenitor. Seed asphericities in the O shell, obtained from a recent 3D model of O shell burning, help trigger a neutrino-driven explosion 330 ms after bounce whereas the shock is not revived in a model based on a spherically symmetric progenitor for at least another 300 ms. We tentatively infer a reduction of the critical luminosity for shock revival by ˜ 20 {per cent} due to pre-collapse perturbations. This indicates that convective seed perturbations play an important role in the explosion mechanism in some progenitors. We follow the evolution of the 18M⊙ model into the explosion phase for more than 2 s and find that the cycle of accretion and mass ejection is still ongoing at this stage. With a preliminary value of 7.7 × 1050 erg for the diagnostic explosion energy, a baryonic neutron star mass of 1.85M⊙, a neutron star kick of ˜ 600 km s^{-1} and a neutron star spin period of ˜ 20 ms at the end of the simulation, the explosion and remnant properties are slightly atypical, but still lie comfortably within the observed distribution. Although more refined simulations and a larger survey of progenitors are still called for, this suggests that a solution to the problem of shock revival and explosion energies in the ballpark of observations is within reach for neutrino-driven explosions in 3D.

  7. [Aging explosive detection using terahertz time-domain spectroscopy].

    PubMed

    Meng, Kun; Li, Ze-ren; Liu, Qiao

    2011-05-01

    Detecting the aging situation of stock explosive is essentially meaningful to the research on the capability, security and stability of explosive. Existing aging explosive detection techniques, such as scan microscope technique, Fourier transfer infrared spectrum technique, gas chromatogram mass spectrum technique and so on, are either not able to differentiate whether the explosive is aging or not, or not able to image the structure change of the molecule. In the present paper, using the density functional theory (DFT), the absorb spectrum changes after the explosive aging were calculated, from which we can clearly find the difference of spectrum between explosive molecule and aging ones in the terahertz band. The terahertz time-domain spectrum (THz-TDS) system as well as its frequency spectrum resolution and measured range are analyzed. Combined with the existing experimental results and the essential characters of the terahertz wave, the application of THz-TDS technique to the detection of aging explosive was demonstrated from the aspects of feasibility, veracity and practicability. On the base of that, the authors advance the new method of aging explosive detection using the terahertz time-domain spectrum technique.

  8. Pyroclast acceleration and energy partitioning in fake explosive eruptions

    NASA Astrophysics Data System (ADS)

    Gaudin, Damien; Taddeucci, Jacopo; Scheu, Bettina; Valentine, Greg; Capponi, Antonio; Kueppers, Ulrich; Graettiger, Allison; Sonder, Ingo

    2014-05-01

    Explosive eruptions are characterized by the fast release of energy, with gas expansion playing a lead role. An excess of pressure may be generated either by the exsolution and accumulation of volatiles (e.g., vulcanian and strombolian explosions) or by in situ vaporization of water (e.g., phreato-magmatic explosions). The release of pressurized gas ejects magma and country rock pyroclasts at velocities that can reach several hundred of meters per second. The amount and velocity of pyroclasts is determined not only by the total released energy, but also by the system-specific dynamics of the energy transfer from gas to pyroclasts. In this context, analogue experiments are crucial, since the amount of available energy is determined. Here, we analyze three different experiments, designed to reproduce different aspects of explosive volcanism, focusing on the acceleration phase of the pyroclasts, in order to compare how the potential energy is transferred to the pyroclasts in different systems. In the first, shock-tube-type experiment, salt crystals resting in a pressurized Plexiglas cylinder are accelerated when a diaphragm set is suddenly opened, releasing the gas. In the second experiment, a pressurized air bubble is released in a water-filled Plexiglas pipe; diaphragm opening causes sudden expansion and bursting of the bubble and ejection of water droplets. In the last experiment, specifically focusing on phreatomagmatic eruptions, buried explosive charges accelerate the overlying loose material. All experiments were monitored by multiple high speed cameras and a variety of sensors. Despite the largely differing settings and processes, particle ejection velocity above the vent from the three experiments share a non-linear decay over time. Fitting this decay allows to estimate a characteristic depth that is related to the specific acceleration processes. Given that the initial available energy is experimentally controlled a priori, the information on the

  9. 4 CFR 25.14 - Weapons and explosives.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 4 Accounts 1 2010-01-01 2010-01-01 false Weapons and explosives. 25.14 Section 25.14 Accounts... AND ON ITS GROUNDS § 25.14 Weapons and explosives. No person while entering or in the GAO Building or on its grounds shall carry or possess firearms, other dangerous or deadly weapons, explosives or...

  10. 4 CFR 25.14 - Weapons and explosives.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 4 Accounts 1 2011-01-01 2011-01-01 false Weapons and explosives. 25.14 Section 25.14 Accounts... AND ON ITS GROUNDS § 25.14 Weapons and explosives. No person while entering or in the GAO Building or on its grounds shall carry or possess firearms, other dangerous or deadly weapons, explosives or...

  11. 4 CFR 25.14 - Weapons and explosives.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 4 Accounts 1 2012-01-01 2012-01-01 false Weapons and explosives. 25.14 Section 25.14 Accounts... AND ON ITS GROUNDS § 25.14 Weapons and explosives. No person while entering or in the GAO Building or on its grounds shall carry or possess firearms, other dangerous or deadly weapons, explosives or...

  12. 4 CFR 25.14 - Weapons and explosives.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 4 Accounts 1 2014-01-01 2013-01-01 true Weapons and explosives. 25.14 Section 25.14 Accounts... AND ON ITS GROUNDS § 25.14 Weapons and explosives. No person while entering or in the GAO Building or on its grounds shall carry or possess firearms, other dangerous or deadly weapons, explosives or...

  13. 4 CFR 25.14 - Weapons and explosives.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 4 Accounts 1 2013-01-01 2013-01-01 false Weapons and explosives. 25.14 Section 25.14 Accounts... AND ON ITS GROUNDS § 25.14 Weapons and explosives. No person while entering or in the GAO Building or on its grounds shall carry or possess firearms, other dangerous or deadly weapons, explosives or...

  14. Electromagnetic field effects in explosives

    NASA Astrophysics Data System (ADS)

    Tasker, Douglas

    2009-06-01

    Present and previous research on the effects of electromagnetic fields on the initiation and detonation of explosives and the electromagnetic properties of explosives are reviewed. Among the topics related to detonating explosives are: measurements of conductivity; enhancement of performance; and control of initiation and growth of reaction. Hayes...()^1 showed a strong correlation of peak electrical conductivity with carbon content of the detonation products. Ershov.......^2 linked detailed electrical conductivity measurements with reaction kinetics and this work was extended to enhance detonation performance electrically;...^3 for this, electrical power densities of the order of 100 TW/m^2 of explosive surface normal to the detonation front were required. However, small electrical powers are required to affect the initiation and growth of reaction.......^4,5 A continuation of this work will be reported. LA-UR 09-00873 .^1 B. Hayes, Procs. of 4th Symposium (International) on Detonation (1965), p. 595. ^2 A. Ershov, P. Zubkov, and L. Luk'yanchikov, Combustion, Explosion, and Shock Waves 10, 776-782 (1974). ^3 M. Cowperthwaite, Procs. 9th Detonation Symposium (1989), p. 388-395. ^4 M. A. Cook and T. Z. Gwyther, ``Influence of Electric Fields on Shock to Detonation Transition,'' (1965). ^5 D. Salisbury, R. Winter, and L. Biddle, Procs. of the APS Topical Conference on Shock Compression of Condensed Matter (2005) p. 1010-1013.

  15. Explosive synchronization as a process of explosive percolation in dynamical phase space

    PubMed Central

    Zhang, Xiyun; Zou, Yong; Boccaletti, S.; Liu, Zonghua

    2014-01-01

    Explosive synchronization and explosive percolation are currently two independent phenomena occurring in complex networks, where the former takes place in dynamical phase space while the latter in configuration space. It has been revealed that the mechanism of EP can be explained by the Achlioptas process, where the formation of a giant component is controlled by a suppressive rule. We here introduce an equivalent suppressive rule for ES. Before the critical point of ES, the suppressive rule induces the presence of multiple, small sized, synchronized clusters, while inducing the abrupt formation of a giant cluster of synchronized oscillators at the critical coupling strength. We also show how the explosive character of ES degrades into a second-order phase transition when the suppressive rule is broken. These results suggest that our suppressive rule can be considered as a dynamical counterpart of the Achlioptas process, indicating that ES and EP can be unified into a same framework. PMID:24903808

  16. Prediction of explosive yield and other characteristics of liquid rocket propellant explosions

    NASA Technical Reports Server (NTRS)

    Farber, E. A.; Smith, J. H.; Watts, E. H.

    1973-01-01

    Work which has been done at the University of Florida in arriving at credible explosive yield values for liquid rocket propellants is presented. The results are based upon logical methods which have been well worked out theoretically and verified through experimental procedures. Three independent methods to predict explosive yield values for liquid rocket propellants are described. All three give the same end result even though they utilize different parameters and procedures. They are: (1) mathematical model; (2) seven chart approach; and (3) critical mass method. A brief description of the methods, how they were derived, how they were applied, and the results which they produced are given. The experimental work used to support and verify the above methods both in the laboratory and in the field with actually explosive mixtures are presented. The methods developed are used and their value demonstrated in analyzing real problems, among them the destruct system of the Saturn 5, and the early configurations of the space shuttle.

  17. 30 CFR 77.1301 - Explosives; magazines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... than 6 feet high. (h) Ammonium nitrate-fuel oil blasting agents shall be physically separated from... explosion hazard. (d) Box-type magazines used to store explosives or detonators in work areas shall be...

  18. Blast overpressure after tire explosion: a fatal case.

    PubMed

    Pomara, Cristoforo; D'Errico, Stefano; Riezzo, Irene; Perilli, Gabriela; Volpe, Umberto; Fineschi, Vittorio

    2013-12-01

    Fatal blast injuries are generally reported in literature as a consequence of the detonation of explosives in war settings. The pattern of lesion depends on the position of the victim in relation to the explosion, on whether the blast tracks through air or water, and whether it happens in the open air or within an enclosed space and the distance from the explosion. Tire explosion-related injuries are rarely reported in literature. This study presents a fatal case of blast overpressure due to the accidental explosion of a truck tire occurring in a tire repair shop. A multidisciplinary approach to the fatality involving forensic pathologists and engineers revealed that the accidental explosion, which caused a series of primary and tertiary blast wave injuries, was due to tire deterioration.

  19. Mechanism of cyanoacetylene photochemistry at 185 and 254 nm

    NASA Technical Reports Server (NTRS)

    Clarke, D. W.; Ferris, J. P.

    1996-01-01

    The role of cyanoacetylene (HC3N) in the atmospheric photochemistry of Titan and its relevance to polymer formation are discussed. Investigation of the relative light absorption of HC3N, acetylene (C2H2), and diacetylene (C4H2) revealed that HC3N is an important absorber of UV light in the 205- to 225-nanometer wavelength region in Titan's polar regions. Laboratory studies established that photolysis of C2H2 initiates the polymerization of HC3N even though the HC3N is not absorbing the UV light. Quantum yield measurements establish that HC3N is 2-5 times as reactive as C2H2 for polymer formation. Photolysis of HC3N with 185-nanometer light in the presence of N2, H2, Ar, or CF4 results in a decrease in the yield of 1,3,5-tricyanobenzene (1,3,5-tcb), while photolysis in the presence of CH4, C2H6, or n-C4H10 results in an increase in 1,3,5-tcb. The rate of loss of HC3N is increased by all gases except H2, where it is unchanged. It was not possible to detect 1,3,5-tcb as a photoproduct when the partial pressure of HC3N was decreased to 1 torr. Photolysis of HC3N with 254-nanometer light in the presence of H2 or N2 results in the formation of 1,2,4-tcb, while photolysis in the presence of CH4, C2H6, or n-C4H10 results in the formation of increasing amounts of 1,3,5-tcb. Mechanisms for the formation of polymers are presented.

  20. Turbulent mixing& combustion in TNT explosions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kuhl, A L; Ferguson, R E; Oppenheim, A K

    2000-12-12

    Effects of turbulent mixing induced by explosion of a 1-g spherical TNT charge in air are investigated. The detonation wave in the charge transforms the solid explosive (C{sub 7}H{sub 5}N{sub 3}O{sub 6}) to gaseous products, rich in C{sub (S)}, and CO. The detonation pressure ({approx}210 kb) causes the products to expand rapidly, driving a blast wave into the surrounding air (Brode, 1959). The interface between the products and air is unstable (Richtmyer, 1960; Meshkov, 1960; Anisimov & Zel'dovich, 1977). As shown in Collage Ia-c, this region rapidly transitions into a turbulent mixing layer (Kuhl, 1996). As the embedded shock, I,more » implodes, it draws the mixing structures (Taylor cavities) into the origin (Collage Id-e). In this way air becomes distributed throughout the hot detonation products gases. This process is enhanced by shock reflections from confining walls. In either case (confined or unconfined), rapid combustion takes place where the expanded detonation products play the role of fuel. This leads to a dramatic increase in chamber pressure (Fig. 1)-in contrast to a corresponding TNT explosion in nitrogen. The problem was modeled as turbulent combustion in an unmixed system at large Reynolds, Peclet and Damkohler numbers (Kuhl et al, 1997). The numerical solution was obtained by a high-order Godunov scheme (Colella & Glaz, 1985). Adaptive Mesh Refinement (Berger & Colella, 1989) was used to follow the turbulent mixing on the computational grid in as much detail as possible. The results reveal all the dynamic features (Fig. 2) of the exothermic process of combustion controlled by fluid-mechanic transport in a highly turbulent field (Kuhl & Oppenheim, 1997), in contrast to the conventional reaction-diffusion mechanism of Zel'dovich & Frank-Kamenetskii (1938).« less

  1. Current trends in explosive detection techniques.

    PubMed

    Caygill, J Sarah; Davis, Frank; Higson, Seamus P J

    2012-01-15

    The detection of explosives and explosive-related compounds has become a heightened priority in recent years for homeland security and counter-terrorism applications. There has been a huge increase in research within this area-through both the development of new, innovative detection approaches and the improvement of existing techniques. Developments for miniaturisation, portability, field-ruggedisation and improvements in stand-off distances, selectivity and sensitivity have been necessary to develop and improve techniques. This review provides a consolidation of information relating to recent advances in explosive detection techniques without being limited to one specific research area or explosive type. The focus of this review will be towards advances in the last 5 years, with the reader being referred to earlier reviews where appropriate. Copyright © 2011. Published by Elsevier B.V.

  2. Toward an Empirically-Based Parametric Explosion Spectral Model

    DTIC Science & Technology

    2010-09-01

    estimated (Richards and Kim, 2009). This archive could potentially provide 200 recordings of explosions at Semipalatinsk Test Site of the former Soviet...estimates of explosion yield, and prior work at the Nevada Test Site (NTS) (e.g., Walter et al., 1995) has found that explosions in weak materials have...2007). Corner frequency scaling of regional seismic phases for underground nuclear explosions at the Nevada Test Site , Bull. Seismol. Soc. Am. 97

  3. 30 CFR 57.6201 - Separation of transported explosive material.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Separation of transported explosive material... MINES Explosives Transportation-Surface and Underground § 57.6201 Separation of transported explosive material. Detonators shall not be transported on the same vehicle or conveyance with other explosives...

  4. 30 CFR 57.6201 - Separation of transported explosive material.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Separation of transported explosive material... MINES Explosives Transportation-Surface and Underground § 57.6201 Separation of transported explosive material. Detonators shall not be transported on the same vehicle or conveyance with other explosives...

  5. New Suspect Identified in Supernova Explosion

    NASA Image and Video Library

    2014-06-04

    Supernovas are often thought of as the tremendous explosions that mark the ends of massive stars' lives. While this is true, not all supernovas occur in this fashion. A common supernova class, called Type Ia, involves the detonation of white dwarfs -- small, dense stars that are already dead. New results from NASA's Spitzer Space Telescope have revealed a rare example of Type Ia explosion, in which a dead star "fed" off an aging star like a cosmic zombie, triggering a blast. The results help researchers piece together how these powerful and diverse events occur. "It's kind of like being a detective," said Brian Williams of NASA's Goddard Space Flight Center in Greenbelt, Maryland, lead author of a study submitted to the Astrophysical Journal. "We look for clues in the remains to try to figure out what happened, even though we weren't there to see it." Read more: 1.usa.gov/1i0PAaa NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  6. Process and apparatus for producing ultrafine explosive particles

    DOEpatents

    McGowan, Michael J.

    1992-10-20

    A method and an improved eductor apparatus for producing ultrafine explosive particles is disclosed. The explosive particles, which when incorporated into a binder system, have the ability to propagate in thin sheets, and have very low impact sensitivity and very high propagation sensitivity. A stream of a solution of the explosive dissolved in a solvent is thoroughly mixed with a stream of an inert nonsolvent by obtaining nonlaminar flow of the streams by applying pressure against the flow of the nonsolvent stream, to thereby diverge the stream as it contacts the explosive solution, and violently agitating the combined stream to rapidly precipitate the explosive particles from the solution in the form of generally spheroidal, ultrafine particles. The two streams are injected coaxially through continuous, concentric orifices of a nozzle into a mixing chamber. Preferably, the nonsolvent stream is injected centrally of the explosive solution stream. The explosive solution stream is injected downstream of and surrounds the nonsolvent solution stream for a substantial distance prior to being ejected into the mixing chamber.

  7. 30 CFR 56.6201 - Separation of transported explosive material.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Separation of transported explosive material... Explosives Transportation § 56.6201 Separation of transported explosive material. Detonators shall not be transported on the same vehicle or conveyance with other explosives except as follows: (a) Detonators in...

  8. 30 CFR 77.1302 - Vehicles used to transport explosives.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Vehicles used to transport explosives. 77.1302... COAL MINES Explosives and Blasting § 77.1302 Vehicles used to transport explosives. (a) Vehicles used to transport explosives, other than blasting agents, shall have substantially constructed bodies, no...

  9. 30 CFR 56.6201 - Separation of transported explosive material.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Separation of transported explosive material... Explosives Transportation § 56.6201 Separation of transported explosive material. Detonators shall not be transported on the same vehicle or conveyance with other explosives except as follows: (a) Detonators in...

  10. 30 CFR 77.1302 - Vehicles used to transport explosives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Vehicles used to transport explosives. 77.1302... COAL MINES Explosives and Blasting § 77.1302 Vehicles used to transport explosives. (a) Vehicles used to transport explosives, other than blasting agents, shall have substantially constructed bodies, no...

  11. Scientific Support for NQR Explosive Detection Development

    DTIC Science & Technology

    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. A critical review of ion mobility spectrometry for the detection of explosives and explosive related compounds.

    PubMed

    Ewing, R G; Atkinson, D A; Eiceman, G A; Ewing, G J

    2001-05-10

    Ion mobility spectrometry has become the most successful and widely used technology for the detection of trace levels of nitro-organic explosives on handbags and carry on-luggage in airports throughout the US. The low detection limits are provided by the efficient ionization process, namely, atmospheric pressure chemical ionization (APCI) reactions in negative polarity. An additional level of confidence in a measurement is imparted by characterization of ions for mobilities in weak electric fields of a drift tube at ambient pressure. Findings from over 30 years of investigations into IMS response to these explosives have been collected and assessed to allow a comprehensive view of the APCI reactions characteristic of nitro-organic explosives. Also, the drift tube conditions needed to obtain particular mobility spectra have been summarized. During the past decade, improvements have occurred in IMS on the understanding of reagent gas chemistries, the influence of temperature on ion stability, and sampling methods. In addition, commercial instruments have been refined to provide fast and reliable measurements for on-site detection of explosives. The gas phase ion chemistry of most explosives is mediated by the fragile CONO(2) bonds or the acidity of protons. Thus, M(-) or M.Cl(-) species are found with only a few explosives and loss of NO(2), NO(3) and proton abstraction reactions are common and complicating pathways. However, once ions are formed, they appear to have stabilities on time scales equal to or longer than ion drift times from 5-20 ms. As such, peak shapes in IMS are suitable for high selectivity and sensitivity.

  13. Insensitive detonator apparatus for initiating large failure diameter explosives

    DOEpatents

    Perry, III, William Leroy

    2015-07-28

    A munition according to a preferred embodiment can include a detonator system having a detonator that is selectively coupled to a microwave source that functions to selectively prime, activate, initiate, and/or sensitize an insensitive explosive material for detonation. The preferred detonator can include an explosive cavity having a barrier within which an insensitive explosive material is disposed and a waveguide coupled to the explosive cavity. The preferred system can further include a microwave source coupled to the waveguide such that microwaves enter the explosive cavity and impinge on the insensitive explosive material to sensitize the explosive material for detonation. In use the preferred embodiments permit the deployment and use of munitions that are maintained in an insensitive state until the actual time of use, thereby substantially preventing unauthorized or unintended detonation thereof.

  14. Global climatology of explosive cyclones

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2013-03-01

    Explosive cyclones, which have rapidly intensifying winds and heavy rain, can seriously threaten life and property. These "meteorological bombs" are difficult to forecast, in part because scientists need a better understanding of the physical mechanisms by which they form. In particular, the large-scale circulation conditions that may contribute to explosive cyclone formation are not well understood.

  15. 49 CFR 172.411 - EXPLOSIVE 1.1, 1.2, 1.3, 1.4, 1.5 and 1.6 labels, and EXPLOSIVE Subsidiary label.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false EXPLOSIVE 1.1, 1.2, 1.3, 1.4, 1.5 and 1.6 labels..., 1.2, 1.3, 1.4, 1.5 and 1.6 labels, and EXPLOSIVE Subsidiary label. (a) Except for size and color....5 and EXPLOSIVE 1.6 labels must be as follows: EXPLOSIVE 1.4: EC02MR91.016 EXPLOSIVE 1.5: EC02MR91...

  16. Underground Nuclear Explosions and Release of Radioactive Noble Gases

    NASA Astrophysics Data System (ADS)

    Dubasov, Yuri V.

    2010-05-01

    Over a period in 1961-1990 496 underground nuclear tests and explosions of different purpose and in different rocks were conducted in the Soviet Union at Semipalatinsk and anovaya Zemlya Test Sites. A total of 340 underground nuclear tests were conducted at the Semipalatinsk Test Site. One hundred seventy-nine explosions (52.6%) among them were classified as these of complete containment, 145 explosions (42.6%) as explosions with weak release of radioactive noble gases (RNG), 12 explosions (3.5%) as explosions with nonstandard radiation situation, and four excavation explosions with ground ejection (1.1%). Thirty-nine nuclear tests had been conducted at the Novaya Zemlya Test Site; six of them - in shafts. In 14 tests (36%) there were no RNG release. Twenty-three tests have been accompanied by RNG release into the atmosphere without sedimental contamination. Nonstandard radiation situation occurred in two tests. In incomplete containment explosions both early-time RNG release (up to ~1 h) and late-time release from 1 to 28 h after the explosion were observed. Sometimes gas release took place for several days, and it occurred either through tunnel portal or epicentral zone, depending on atmospheric air temperature.

  17. Solid Rocket Launch Vehicle Explosion Environments

    NASA Technical Reports Server (NTRS)

    Richardson, E. H.; Blackwood, J. M.; Hays, M. J.; Skinner, T.

    2014-01-01

    Empirical explosion data from full scale solid rocket launch vehicle accidents and tests were collected from all available literature from the 1950s to the present. In general data included peak blast overpressure, blast impulse, fragment size, fragment speed, and fragment dispersion. Most propellants were 1.1 explosives but a few were 1.3. Oftentimes the data from a single accident was disjointed and/or missing key aspects. Despite this fact, once the data as a whole was digitized, categorized, and plotted clear trends appeared. Particular emphasis was placed on tests or accidents that would be applicable to scenarios from which a crew might need to escape. Therefore, such tests where a large quantity of high explosive was used to initiate the solid rocket explosion were differentiated. Also, high speed ground impacts or tests used to simulate such were also culled. It was found that the explosions from all accidents and applicable tests could be described using only the pressurized gas energy stored in the chamber at the time of failure. Additionally, fragmentation trends were produced. Only one accident mentioned the elusive "small" propellant fragments, but upon further analysis it was found that these were most likely produced as secondary fragments when larger primary fragments impacted the ground. Finally, a brief discussion of how this data is used in a new launch vehicle explosion model for improving crew/payload survival is presented.

  18. What factors control superficial lava dome explosivity?

    PubMed

    Boudon, Georges; Balcone-Boissard, Hélène; Villemant, Benoît; Morgan, Daniel J

    2015-09-30

    Dome-forming eruption is a frequent eruptive style and a major hazard on numerous volcanoes worldwide. Lava domes are built by slow extrusion of degassed, viscous magma and may be destroyed by gravitational collapse or explosion. The triggering of lava dome explosions is poorly understood: here we propose a new model of superficial lava-dome explosivity based upon a textural and geochemical study (vesicularity, microcrystallinity, cristobalite distribution, residual water contents, crystal transit times) of clasts produced by key eruptions. Superficial explosion of a growing lava dome may be promoted through porosity reduction caused by both vesicle flattening due to gas escape and syn-eruptive cristobalite precipitation. Both processes generate an impermeable and rigid carapace allowing overpressurisation of the inner parts of the lava dome by the rapid input of vesiculated magma batches. The relative thickness of the cristobalite-rich carapace is an inverse function of the external lava dome surface area. Explosive activity is thus more likely to occur at the onset of lava dome extrusion, in agreement with observations, as the likelihood of superficial lava dome explosions depends inversely on lava dome volume. This new result is of interest for the whole volcanological community and for risk management.

  19. Revisiting Shock Initiation Modeling of Homogeneous Explosives

    NASA Astrophysics Data System (ADS)

    Partom, Yehuda

    2013-04-01

    Shock initiation of homogeneous explosives has been a subject of research since the 1960s, with neat and sensitized nitromethane as the main materials for experiments. A shock initiation model of homogeneous explosives was established in the early 1960s. It involves a thermal explosion event at the shock entrance boundary, which develops into a superdetonation that overtakes the initial shock. In recent years, Sheffield and his group, using accurate experimental tools, were able to observe details of buildup of the superdetonation. There are many papers on modeling shock initiation of heterogeneous explosives, but there are only a few papers on modeling shock initiation of homogeneous explosives. In this article, bulk reaction reactive flow equations are used to model homogeneous shock initiation in an attempt to reproduce experimental data of Sheffield and his group. It was possible to reproduce the main features of the shock initiation process, including thermal explosion, superdetonation, input shock overtake, overdriven detonation after overtake, and the beginning of decay toward Chapman-Jouget (CJ) detonation. The time to overtake (TTO) as function of input pressure was also calculated and compared to the experimental TTO.

  20. Isolator fragmentation and explosive initiation tests

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dickson, Peter; Rae, Philip John; Foley, Timothy J.

    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 estimatesmore » 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.« less

  1. Isolator fragmentation and explosive initiation tests

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dickson, Peter; Rae, Philip John; Foley, Timothy J.

    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 thatmore » 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.« less

  2. Maintenance energy requirements of odor detection, explosive detection and human detection working dogs.

    PubMed

    Mullis, Rebecca A; Witzel, Angela L; Price, Joshua

    2015-01-01

    Despite their important role in security, little is known about the energy requirements of working dogs such as odor, explosive and human detection dogs. Previous researchers have evaluated the energy requirements of individual canine breeds as well as dogs in exercise roles such as sprint racing. This study is the first to evaluate the energy requirements of working dogs trained in odor, explosive and human detection. This retrospective study evaluated twenty adult dogs who maintained consistent body weights over a six month period. During this time, the average energy consumption was [Formula: see text] or two times the calculated resting energy requirement ([Formula: see text]). No statistical differences were found between breeds, age or sex, but a statistically significant association (p = 0.0033, R-square = 0.0854) was seen between the number of searches a dog performs and their energy requirement. Based on this study's population, it appears that working dogs have maintenance energy requirements similar to the 1974 National Research Council's (NRC) maintenance energy requirement of [Formula: see text] (National Research Council (NRC), 1974) and the [Formula: see text] reported for young laboratory beagles (Rainbird & Kienzle, 1990). Additional research is needed to determine if these data can be applied to all odor, explosive and human detection dogs and to determine if other types of working dogs (tracking, search and rescue etc.) have similar energy requirements.

  3. 29 CFR 1926.905 - Loading of explosives or blasting agents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Loading of explosives or blasting agents. 1926.905 Section... Explosives § 1926.905 Loading of explosives or blasting agents. (a) Procedures that permit safe and efficient... have contained explosives or blasting agents. (g) No explosives or blasting agents shall be left...

  4. Raman chemical imaging of explosive-contaminated fingerprints.

    PubMed

    Emmons, E D; Tripathi, A; Guicheteau, J A; Christesen, S D; Fountain, A W

    2009-11-01

    Raman chemical imaging (RCI) has been used to detect and identify explosives in contaminated fingerprints. Bright-field imaging is used to identify regions of interest within a fingerprint, which can then be examined to determine their chemical composition using RCI and fluorescence imaging. Results are presented where explosives in contaminated fingerprints are identified and their spatial distributions are obtained. Identification of explosives is obtained using Pearson's cosine cross-correlation technique using the characteristic region (500-1850 cm(-1)) of the spectrum. This study shows the ability to identify explosives nondestructively so that the fingerprint remains intact for further biometric analysis. Prospects for forensic examination of contaminated fingerprints are discussed.

  5. [Discussion of the Roles of Medical Social Workers in the Response to the Explosion Incident at Formosa Fun Coast].

    PubMed

    Yueh, Hsin-Tien; Sung, Hsien-Yi; Wu, Chia-Feng

    2016-02-01

    Medical social workers apply the theories of "person in the environment" (PIE) and "ecological perspective" as practical foundations. Furthermore, they emphasize the people, the environment, and the interactions between these two. When burn patients from the explosion at Formosa Fun Coast were sent to hospitals, social workers not only provided care and assessed the impact on burn patients but also assisted in supporting the family members of these patients. This article discusses the various roles of social workers within different systems. In the individual system, we use Eric Erickson's theory of psychosocial development to evaluate the patient's crisis and the tasks of social workers. Secondly, in the systems of family, school, and work, we assess the relationships between a patient, his/her significant others, and caregivers as well as the interactions among sub-systems in the family. In the community and cultural systems, we focus on the social resources that may be utilized by the burn patients after discharge. Moreover, we add a time frame to examine our major tasks, including the initial stage, the middle stage, and the preparation-for-discharge stage. We explore the roles of social workers, the applicable theories, and the goals for each stage.

  6. Determining the explosion risk level and the explosion hazard area for a group of natural gas wells

    NASA Astrophysics Data System (ADS)

    Gligor, A.; Petrescu, V.; Deac, C.; Bibu, M.

    2016-11-01

    Starting from the fact that the natural gas engineering profession is generally associated with a high occupational risk, the current paper aims to help increase the safety of natural gas wells and reduce the risk of work-related accidents, as well as the occurrence of professional illnesses, by applying an assessment method that has proven its efficiency in other industrial areas in combination with a computer-aided design software. More specifically, the paper focuses on two main research directions: assessing the explosion risk for employees working at natural gas wells and indicating areas with a higher explosion hazard by using a modern software that allows their presentation in 3D. The appropriate zoning of industrial areas allows to group the various functional areas function of the probability of the occurrence of a dangerous element, such as an explosive atmosphere and subsequently it allows also to correctly select the electrical and mechanical equipment that will be used in that area, since electrical apparatuses that are otherwise found in normal work environments cannot generally be used in areas with explosion hazard, because of the risk that an electric spark, an electrostatic discharge etc. ignites the explosive atmosphere.

  7. Biodegradation of 1,2,3- and 1,2,4-Trichlorobenzene in Soil and in Liquid Enrichment Culture †

    PubMed Central

    Marinucci, A. C.; Bartha, R.

    1979-01-01

    The biodegradation of radiochemically pure (99%) 1,2,3- and 1,2,4-trichlorobenzene (TCB) in soil was investigated. Experimental difficulties posed by the high volatility and slow biodegradation rate of the TCBs were partially overcome by using a specially designed incubation and trapping apparatus. Evolution of 14CO2 from active versus poisoned soil dosed with 50 μg of the individual TCBs per g gave conclusive proof that both isomers are biodegradable. At 20°C, 1,2,4-TCB was mineralized at an approximate rate of 1 nmol/day per 20 g of soil sample, and 1,2,3-TCB was mineralized at one-half to one-third that rate. Mineral fertilizers or cosubstrates failed to increase TCB mineralization rates in soil. Anaerobic conditions had a negative effect on mineralization, and increased temperatures had a positive effect. With increasing 1,2,4-TCB concentrations, 14CO2 evolution exhibited saturation kinetics with an apparent Km of 55.5 nmol per g of soil. Recovery of total radioactivity was good from soil containing high organic matter concentrations. From low-organic-matter soil, some of the radioactivity was recovered only on combustion, and overall recovery was lower. In soil-inoculated liquid culture, the cosubstrates glucose and benzene caused a slight stimulation of 1,2,4-TCB mineralization. Cochromatography of known standards with the extracts of soil pretreated with [14C]TCBs indicated that 3,4,5-trichlorophenol, 2,6-dichlorophenol and, to a lesser degree, 2,3-dichlorophenol were present in soils incubated with 1,2,3-TCB. 2,4-, 2,5-, and 3,4-dichlorophenol were present in soils incubated with 1,2,4-TCB. PMID:120698

  8. Utility of Decision Rules for Transcutaneous Bilirubin Measurements

    PubMed Central

    Burgos, Anthony E.; Flaherman, Valerie; Chung, Esther K.; Simpson, Elizabeth A.; Goyal, Neera K.; Von Kohorn, Isabelle; Dhepyasuwan, Niramol

    2016-01-01

    BACKGROUND: Transcutaneous bilirubin (TcB) meters are widely used for screening newborns for jaundice, with a total serum bilirubin (TSB) measurement indicated when the TcB value is classified as “positive” by using a decision rule. The goal of our study was to assess the clinical utility of 3 recommended TcB screening decision rules. METHODS: Paired TcB/TSB measurements were collected at 34 newborn nursery sites. At 27 sites (sample 1), newborns were routinely screened with a TcB measurement. For sample 2, sites that typically screen with TSB levels also obtained a TcB measurement for the study. Three decision rules to define a positive TcB measurement were evaluated: ≥75th percentile on the Bhutani nomogram, 70% of the phototherapy level, and within 3 mg/dL of the phototherapy threshold. The primary outcome was a TSB level at/above the phototherapy threshold. The rate of false-negative TcB screens and percentage of blood draws avoided were calculated for each decision rule. RESULTS: For sample 1, data were analyzed on 911 paired TcB-TSB measurements from a total of 8316 TcB measurements. False-negative rates were <10% with all decision rules; none identified all 31 newborns with a TSB level at/above the phototherapy threshold. The percentage of blood draws avoided ranged from 79.4% to 90.7%. In sample 2, each rule correctly identified all 8 newborns with TSB levels at/above the phototherapy threshold. CONCLUSIONS: Although all of the decision rules can be used effectively to screen newborns for jaundice, each will “miss” some infants with a TSB level at/above the phototherapy threshold. PMID:27244792

  9. Rotor Systems Research Aircraft /RSRA/ canopy explosive severance/fracture

    NASA Technical Reports Server (NTRS)

    Bement, L. J.

    1976-01-01

    The Rotor Systems Research Aircraft (RSRA), a compound rotor/fixed-wing aircraft, incorporates an emergency escape system for the three crew members; to achieve unobstructed egress, the overhead acrylic canopies of each crew member will be explosively severed and fractured into predictably small, low-mass pieces. A canopy explosive severance/fracture system was developed under this investigation that included the following system design considerations: selection of canopy and explosive materials, determining the acrylic's explosive severance and fracture characteristics, evaluating the effects of installation variables and temperature, determining the most effective explosive patterns, conducting full-scale, flat and double-curvature canopy tests, and evaluating the effects of back-blast of the explosive into the cockpit.

  10. Standoff laser-based spectroscopy for explosives detection

    NASA Astrophysics Data System (ADS)

    Gaft, M.; Nagli, L.

    2007-10-01

    Real time detection and identification of explosives at a standoff distance is a major issue in efforts to develop defense against so-called Improvised Explosive Devices (IED). It is recognized that the only technique, which is potentially capable to standoff detection of minimal amounts of explosives is laser-based spectroscopy. LDS activity is based on a combination of laser-based spectroscopic methods with orthogonal capabilities. Our technique belongs to trace detection, namely to its micro-particles variety. It is based on commonly held belief that surface contamination was very difficult to avoid and could be exploited for standoff detection. We has applied optical techniques including gated Raman and time-resolved luminescence spectroscopy for detection of main explosive materials, both factory and homemade. We developed and tested a Raman system for the field remote detection and identification of minimal amounts of explosives on relevant surfaces at a distance of up to 30 meters.

  11. Explosion interaction with water in a tube

    NASA Astrophysics Data System (ADS)

    Homae, T.; Sugiyama, Y.; Wakabayashi, K.; Matsumura, T.; Nakayama, Y.

    2017-02-01

    As proposed and legislated in Japan, subsurface magazines have an explosive storage chamber, a horizontal passageway, and a vertical shaft for a vent. The authors found that a small amount of water on the floor of the storage chamber mitigated blast pressure remarkably. The mitigation mechanism has been examined more closely. To examine the effect of water, the present study assesses explosions in a transparent, square cross section, and a straight tube. A high-speed camera used to observe the tube interior. Blast pressure in and around the tube was also measured. Images obtained using the high-speed camera revealed that water inside the tube did not move after the explosion. Differences between cases of tubes without water and with water were unclear. Along with blast pressure measurements, these study results suggest that blast pressure mitigation by water occurs because of interaction between the explosion and the water near the explosion point.

  12. Explosives remain preferred methods for platform abandonment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pulsipher, A.; Daniel, W. IV; Kiesler, J.E.

    1996-05-06

    Economics and safety concerns indicate that methods involving explosives remain the most practical and cost-effective means for abandoning oil and gas structures in the Gulf of Mexico. A decade has passed since 51 dead sea turtles, many endangered Kemp`s Ridleys, washed ashore on the Texas coast shortly after explosives helped remove several offshore platforms. Although no relationship between the explosions and the dead turtles was ever established, in response to widespread public concern, the US Minerals Management Service (MMS) and National Marine Fisheries Service (NMFS) implemented regulations limiting the size and timing of explosive charges. Also, more importantly, they requiredmore » that operators pay for observers to survey waters surrounding platforms scheduled for removal for 48 hr before any detonations. If observers spot sea turtles or marine mammals within the danger zone, the platform abandonment is delayed until the turtles leave or are removed. However, concern about the effects of explosives on marine life remains.« less

  13. 27 CFR 555.205 - Movement of explosive materials.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Movement of explosive materials. 555.205 Section 555.205 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO... Movement of explosive materials. All explosive materials must be kept in locked magazines meeting the...

  14. 30 CFR 19.7 - Protection against explosion hazard.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC CAP LAMPS § 19.7 Protection against explosion hazard. Unless properly designed, electric cap lamps may present two sources of probable explosion hazards..., if the lamp is designed and constructed to prevent the ignition of explosive mixtures of methane and...

  15. 30 CFR 19.7 - Protection against explosion hazard.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC CAP LAMPS § 19.7 Protection against explosion hazard. Unless properly designed, electric cap lamps may present two sources of probable explosion hazards..., if the lamp is designed and constructed to prevent the ignition of explosive mixtures of methane and...

  16. 30 CFR 19.7 - Protection against explosion hazard.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC CAP LAMPS § 19.7 Protection against explosion hazard. Unless properly designed, electric cap lamps may present two sources of probable explosion hazards..., if the lamp is designed and constructed to prevent the ignition of explosive mixtures of methane and...

  17. 30 CFR 19.7 - Protection against explosion hazard.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC CAP LAMPS § 19.7 Protection against explosion hazard. Unless properly designed, electric cap lamps may present two sources of probable explosion hazards..., if the lamp is designed and constructed to prevent the ignition of explosive mixtures of methane and...

  18. 30 CFR 57.6102 - Explosive material storage practices.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Explosive material storage practices. 57.6102... Storage-Surface and Underground § 57.6102 Explosive material storage practices. (a) Explosive material... instructions and the date-plant-shift code are maintained with the product. Storage—Surface Only ...

  19. 30 CFR 57.6130 - Explosive material storage facilities.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Explosive material storage facilities. 57.6130 Section 57.6130 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage-Surface Only § 57.6130 Explosive material storage facilities. (a) Detonators and explosives shall...

  20. 30 CFR 57.6102 - Explosive material storage practices.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Explosive material storage practices. 57.6102... Storage-Surface and Underground § 57.6102 Explosive material storage practices. (a) Explosive material... instructions and the date-plant-shift code are maintained with the product. Storage—Surface Only ...

  1. 30 CFR 57.6130 - Explosive material storage facilities.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Explosive material storage facilities. 57.6130 Section 57.6130 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage-Surface Only § 57.6130 Explosive material storage facilities. (a) Detonators and explosives shall...

  2. 49 CFR 173.54 - Forbidden explosives.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... subpart. (b) An explosive mixture or device containing a chlorate and also containing: (1) An ammonium... explosive. (d) Propellants that are unstable, condemned or deteriorated. (e) Nitroglycerin, diethylene... detonator. (h) Fireworks containing yellow or white phosphorus. (i) A toy torpedo, the maximum outside...

  3. 49 CFR 173.54 - Forbidden explosives.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... subpart. (b) An explosive mixture or device containing a chlorate and also containing: (1) An ammonium... explosive. (d) Propellants that are unstable, condemned or deteriorated. (e) Nitroglycerin, diethylene... detonator. (h) Fireworks containing yellow or white phosphorus. (i) A toy torpedo, the maximum outside...

  4. Disrupting Improvised Explosive Device Terror Campaigns: Basic Research Opportunities

    DTIC Science & Technology

    2008-01-01

    2008 2. REPORT TYPE 3. DATES COVERED 00-00-2008 to 00-00-2008 4. TITLE AND SUBTITLE Disrupting Improvised Explosive Device Terror Campaigns... Explosive Device Terror Campaigns: Basic Research Opportunities A WORKSHOP REPORT Committee on Defeating Improvised Explosive Devices...iv v COMMITTEE ON DEFEATING IMPROVISED EXPLOSIVE DEVICES: BASIC RESEARCH TO INTERRUPT THE IED DELIVERY CHAIN Chairperson

  5. The Nuclear Barcode: a New Taggant for Identifying Explosives

    NASA Astrophysics Data System (ADS)

    Seman, James; Johnson, Catherine; Castaño, Carlos

    2017-06-01

    Creating an effective taggant system for explosives is a challenging problem since the taggant used must be designed to endure the detonation process. A new taggant for use in explosives has been recently developed and named the `nuclear barcode'. The nuclear barcode tags explosives by adding low concentrations of eight different elements to the explosive, and then reads the tag from the post-blast residue using neutron activation analysis (NAA) to identify the elements and their concentrations. The nuclear barcode can be used to identify explosives after detonation by sampling the post-blast residue that is deposited due to incomplete reaction of the explosives. This method of tagging explosives creates an identifying taggant that survives detonation as NAA detects atomic nuclei as opposed to using any chemical or physical properties of the taggant that don't always survive the detonation process. Additional advantages this taggant method offers is ease of recovery of the taggant after detonation, and a total of 25.6 billion possible taggants as currently conceived, which enables the nuclear barcode to be used to tag individual batches of explosives. This paper describes the development of the nuclear barcode taggant system and its potential use in the explosives industry.

  6. Classification of explosives transformation products in plant tissue

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Larson, S.L.; Jones, R.P.; Escalon, L.

    Explosives contamination in surface or groundwater used for the irrigation of food crops and phytoremediation of explosives-contaminated soil or water using plant-assisted biodegradation have brought about concerns as to the fate of explosives in plants. Liquid scintillation counting, high-performance liquid chromatography, and gel permeation chromatography were utilized to characterize explosives (hexahydro-1,3,5-trinitro-1,3,5-triazine and trinitrotoluene) and their metabolites in plant tissues obtained from three separate studies. Analyzing tissues of yellow nutsedge (Cyperus esculentus), corn (Zea mays), lettuce (Lacuta sativa), tomato (Lyopersicum esculentum), radish (Raphanus sativus), and parrot feather (Myriophyllum aquaticum) from three studies where exposure to explosives at nontoxic levels occurred showedmore » that extensive transformation of the explosive contaminant occurred, variations were noted in uptake and transformation between terrestrial and aquatic plants, the products had significantly higher polarity and water solubility than the parent compounds, and the molecular sizes of the transformation products were significantly greater than those of the parent compounds.« less

  7. Liquid explosions induced by X-ray laser pulses

    DOE PAGES

    Stan, Claudiu A.; Milathianaki, Despina; Laksmono, Hartawan; ...

    2016-05-23

    Explosions are spectacular and intriguing phenomena that expose the dynamics of matter under extreme conditions. We investigated, using time-resolved imaging, explosions induced by ultraintense X-ray laser pulses in water drops and jets. Our observations revealed an explosive vaporization followed by high-velocity interacting flows of liquid and vapour, and by the generation of shock trains in the liquid jets. These flows are different from those previously observed in laser ablation, owing to a simpler spatial pattern of X-ray absorption. We show that the explosion dynamics in our experiments is consistent with a redistribution of absorbed energy, mediated by a pressure ormore » shock wave in the liquid, and we model the effects of explosions, including their adverse impact on X-ray laser experiments. As a result, X-ray laser explosions have predictable dynamics that may prove useful for controlling the state of pure liquids over broad energy scales and timescales, and for triggering pressure-sensitive molecular dynamics in solutions.« less

  8. Detonation Properties Measurements for Inorganic Explosives

    NASA Astrophysics Data System (ADS)

    Morgan, Brent A.; Lopez, Angel

    2005-03-01

    Many commonly available explosive materials have never been quantitatively or theoretically characterized in a manner suitable for use in analytical models. This includes inorganic explosive materials used in spacecraft ordnance, such as zirconium potassium perchlorate (ZPP). Lack of empirical information about these materials impedes the development of computational techniques. We have applied high fidelity measurement techniques to experimentally determine the pressure and velocity characteristics of ZPP, a previously uncharacterized explosive material. Advances in measurement technology now permit the use of very small quantities of material, thus yielding a significant reduction in the cost of conducting these experiments. An empirical determination of the explosive behavior of ZPP derived a Hugoniot for ZPP with an approximate particle velocity (uo) of 1.0 km/s. This result compares favorably with the numerical calculations from the CHEETAH thermochemical code, which predicts uo of approximately 1.2 km/s under ideal conditions.

  9. Electromagnetic effects on explosive reaction and plasma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tasker, Douglas G; Whitley, Von H; Mace, Jonathan L

    2010-01-01

    A number of studies have reported that electric fields can have quantifiable effects on the initiation and growth of detonation, yet the mechanisms of these effects are not clear. Candidates include Joule heating of the reaction zone, perturbations to the activation energy for chemical reaction, reduction of the Peierls energy barrier that facilitates dislocation motion, and acceleration of plasma projected from the reaction zone. In this study the possible role of plasma in the initiation and growth of explosive reaction is investigated. The effects of magnetic and electric field effects on reaction growth will be reviewed and recent experiments reported.

  10. 30 CFR 57.6960 - Mixing of explosive material.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Mixing of explosive material. 57.6960 Section... General Requirements-Underground Only § 57.6960 Mixing of explosive material. (a) The mixing of... to the hazards associated with the mixing of the bulk explosive material underground. (b) Storage...

  11. 30 CFR 57.6960 - Mixing of explosive material.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Mixing of explosive material. 57.6960 Section... General Requirements-Underground Only § 57.6960 Mixing of explosive material. (a) The mixing of... to the hazards associated with the mixing of the bulk explosive material underground. (b) Storage...

  12. 30 CFR 57.6960 - Mixing of explosive material.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Mixing of explosive material. 57.6960 Section... General Requirements-Underground Only § 57.6960 Mixing of explosive material. (a) The mixing of... to the hazards associated with the mixing of the bulk explosive material underground. (b) Storage...

  13. 30 CFR 57.6960 - Mixing of explosive material.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Mixing of explosive material. 57.6960 Section... General Requirements-Underground Only § 57.6960 Mixing of explosive material. (a) The mixing of... to the hazards associated with the mixing of the bulk explosive material underground. (b) Storage...

  14. 30 CFR 57.6960 - Mixing of explosive material.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Mixing of explosive material. 57.6960 Section... General Requirements-Underground Only § 57.6960 Mixing of explosive material. (a) The mixing of... to the hazards associated with the mixing of the bulk explosive material underground. (b) Storage...

  15. 29 CFR 1926.902 - Surface transportation of explosives.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... electric) shall not be transported in the same vehicle with other explosives. (e) Vehicles used for... prevent contact with containers of explosives. (h) Every motor vehicle or conveyance used for transporting... Carriers. (b) Motor vehicles or conveyances transporting explosives shall only be driven by, and be in the...

  16. 30 CFR 56.6130 - Explosive material storage facilities.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Explosive material storage facilities. 56.6130 Section 56.6130 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage § 56.6130 Explosive material storage facilities. (a) Detonators and explosives shall be stored in...

  17. 30 CFR 56.6102 - Explosive material storage practices.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Explosive material storage practices. 56.6102 Section 56.6102 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage § 56.6102 Explosive material storage practices. (a) Explosive material shall be— (1) Stored in a...

  18. 30 CFR 56.6102 - Explosive material storage practices.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Explosive material storage practices. 56.6102 Section 56.6102 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage § 56.6102 Explosive material storage practices. (a) Explosive material shall be— (1) Stored in a...

  19. 30 CFR 56.6130 - Explosive material storage facilities.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Explosive material storage facilities. 56.6130 Section 56.6130 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage § 56.6130 Explosive material storage facilities. (a) Detonators and explosives shall be stored in...

  20. What factors control superficial lava dome explosivity?

    PubMed Central

    Boudon, Georges; Balcone-Boissard, Hélène; Villemant, Benoît; Morgan, Daniel J.

    2015-01-01

    Dome-forming eruption is a frequent eruptive style and a major hazard on numerous volcanoes worldwide. Lava domes are built by slow extrusion of degassed, viscous magma and may be destroyed by gravitational collapse or explosion. The triggering of lava dome explosions is poorly understood: here we propose a new model of superficial lava-dome explosivity based upon a textural and geochemical study (vesicularity, microcrystallinity, cristobalite distribution, residual water contents, crystal transit times) of clasts produced by key eruptions. Superficial explosion of a growing lava dome may be promoted through porosity reduction caused by both vesicle flattening due to gas escape and syn-eruptive cristobalite precipitation. Both processes generate an impermeable and rigid carapace allowing overpressurisation of the inner parts of the lava dome by the rapid input of vesiculated magma batches. The relative thickness of the cristobalite-rich carapace is an inverse function of the external lava dome surface area. Explosive activity is thus more likely to occur at the onset of lava dome extrusion, in agreement with observations, as the likelihood of superficial lava dome explosions depends inversely on lava dome volume. This new result is of interest for the whole volcanological community and for risk management. PMID:26420069

  1. Thermodynamic Model of Afterburning in Explosions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    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. Decreasing Friction Sensitivity for Primary Explosives

    NASA Astrophysics Data System (ADS)

    Matyáš, Robert; Šelešovský, Jakub

    2014-04-01

    Primary explosives are a group of explosives that are widely used in various initiating devices. One of their properties is sufficient sensitivity to initiating stimuli. However, their sensitivity often introduces a safety risk during their production and subsequent handling. It is generally known that water can be used to desensitize these compounds. The most commonly used industrial primary explosives (lead azide, lead styphnate, tetrazene, and diazodinitrophenol) were mixed with water in various ratios and the sensitivity to friction was determined for all mixtures. It was found that even a small addition of water (5-10%) considerably lowered the friction sensitivity.

  3. PUSHing core-collapse simulations to explosion

    NASA Astrophysics Data System (ADS)

    Fröhlich, C.; Perego, A.; Hempe, M.; Ebinger, K.; Eichler, M.; Casanova, J.; Liebendörfer, M.; Thielemann, F.-K.

    2018-01-01

    We report on the PUSH method for artificially triggering core-collapse supernova explosions of massive stars in spherical symmetry. The PUSH method increases the energy deposition in the gain region proportionally to the heavy flavor neutrino fluxes.We summarize the parameter dependence of the method and calibrate PUSH to reproduce SN 1987A observables. We identify a best-fit progenitor and set of parameters that fit the explosion properties of SN 1987A, assuming 0.1 M⊙ of fallback. For the explored progenitor range of 18-21 M⊙, we find correlations between explosion properties and the compactness of the progenitor model.

  4. Measuring explosive non-ideality

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    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}.more » 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.« less

  5. Airport testing an explosives detection portal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rhykerd, C.; Linker, K.; Hannum, D.

    1998-08-01

    At the direction of the US Congress, following the Pan Am 103 and TWA 800 crashes, the Federal Aviation Administration funded development of non-invasive techniques to screen airline passengers for explosives. Such an explosives detection portal, developed at Sandia National Laboratories, was field tested at the Albuquerque International airport in September 1997. During the 2-week field trial, 2,400 passengers were screened and 500 surveyed. Throughput, reliability, maintenance and sensitivity were studied. Follow-up testing at Sandia and at Idaho National Engineering and Environmental Laboratory was conducted. A passenger stands in the portal for five seconds while overhead fans blow air overmore » his body. Any explosive vapors or dislodged particles are collected in vents at the feet. Explosives are removed from the air in a preconcentrator and subsequently directed into an ion mobility spectrometer for detection. Throughput measured 300 passengers per hour. The non-invasive portal can detect subfingerprint levels of explosives residue on clothing. A survey of 500 passengers showed a 97% approval rating, with 99% stating that such portals, if effective, should be installed in airports to improve security. Results of the airport test, as well as operational issues, are discussed.« less

  6. Swell Sleeves for Testing Explosive Devices

    NASA Technical Reports Server (NTRS)

    Hinkel, Todd J.; Dean, Richard J.; Hohmann, Carl W.; Hacker, Scott C.; Harrington, Douglas W.; Bacak, James W.

    2003-01-01

    A method of testing explosive and pyrotechnic devices involves exploding the devices inside swell sleeves. Swell sleeves have been used previously for measuring forces. In the present method, they are used to obtain quantitative indications of the energy released in explosions of the devices under test. A swell sleeve is basically a thick-walled, hollow metal cylinder threaded at one end to accept a threaded surface on a device to be tested (see Figure 1). Once the device has been tightly threaded in place in the swell sleeve, the device-and-swell-sleeve assembly is placed in a test fixture, then the device is detonated. After the explosion, the assembly is removed from the test fixture and placed in a coordinate-measuring machine for measurement of the diameter of the swell sleeve as a function of axial position. For each axial position, the original diameter of the sleeve is subtracted from the diameter of the sleeve as swollen by the explosion to obtain the diametral swelling as a function of axial position (see Figure 2). The amount of swelling is taken as a measure of the energy released in the explosion. The amount of swelling can be compared to a standard amount of swelling to determine whether the pyrotechnic device functioned as specified.

  7. 36 CFR § 504.14 - Weapons and explosives.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Weapons and explosives. § 504... REGULATIONS GOVERNING SMITHSONIAN INSTITUTION BUILDINGS AND GROUNDS § 504.14 Weapons and explosives. No person while on the premises shall carry firearms, other dangerous or deadly weapons, or explosives, either...

  8. 30 CFR 75.1311 - Transporting explosives and detonators.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Transporting explosives and detonators. 75.1311... Transporting explosives and detonators. (a) When explosives and detonators are to be transported underground... transported by any cars or vehicles— (1) The cars or vehicles shall be marked with warnings to identify the...

  9. 30 CFR 75.1311 - Transporting explosives and detonators.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Transporting explosives and detonators. 75.1311... Transporting explosives and detonators. (a) When explosives and detonators are to be transported underground... transported by any cars or vehicles— (1) The cars or vehicles shall be marked with warnings to identify the...

  10. Explosive cord

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Device, jetcord, is metal-clad linear explosive of sufficient flexibility to allow forming into intricate shapes. Total effect is termed ''cutting'' with jetcord consistently ''cutting'' a target of greater thickness than can be penetrated. Applications include sheet metal working, pipe cutting and fire-fighting.

  11. Validation of transcutaneous bilirubin nomogram for identifying neonatal hyperbilirubinemia in healthy Chinese term and late-preterm infants: a multicenter study.

    PubMed

    Yu, Zhangbin; Han, Shuping; Wu, Jinxia; Li, Mingxia; Wang, Huaiyan; Wang, Jimei; Liu, Jiebo; Pan, Xinnian; Yang, Jie; Chen, Chao

    2014-01-01

    to prospectively validate a previously constructed transcutaneous bilirubin (TcB) nomogram for identifying severe hyperbilirubinemia in healthy Chinese term and late-preterm infants. this was a multicenter study that included 9,174 healthy term and late-preterm infants in eight hospitals of China. TcB measurements were performed using a JM-103 bilirubinometer. TcB values were plotted on a previously developed TcB nomogram, to identify the predictive ability for subsequent significant hyperbilirubinemia. in the present study, 972 neonates (10.6%) developed significant hyperbilirubinemia. The 40(th) percentile of the nomogram could identify all neonates who were at risk of significant hyperbilirubinemia, but with a low positive predictive value (PPV) (18.9%). Of the 453 neonates above the 95(th) percentile, 275 subsequently developed significant hyperbilirubinemia, with a high PPV (60.7%), but with low sensitivity (28.3%). The 75(th) percentile was highly specific (81.9%) and moderately sensitive (79.8%). The area under the curve (AUC) for the TcB nomogram was 0.875. this study validated the previously developed TcB nomogram, which could be used to predict subsequent significant hyperbilirubinemia in healthy Chinese term and late-preterm infants. However, combining TcB nomogram and clinical risk factors could improve the predictive accuracy for severe hyperbilirubinemia, which was not assessed in the study. Further studies are necessary to confirm this combination. Copyright © 2014 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  12. One-Dimensional Time to Explosion (Thermal Sensitivity) of ANPZ

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hsu, P.; Hust, G.; McClelland, M.

    Incidents caused by fire and combat operations can heat energetic materials that may lead to thermal explosion and result in structural damage and casualty. Some explosives may thermally explode at fairly low temperatures (< 100 C) and the violence from thermal explosion may cause a significant damage. Thus it is important to understand the response of energetic materials to thermal insults. The One Dimensional Time to Explosion (ODTX) system at the Lawrence Livermore National Laboratory has been used for decades to measure times to explosion, threshold thermal explosion temperature, and determine kinetic parameters of energetic materials. Samples of different configurationsmore » (pressed part, powder, paste, and liquid) can be tested in the system. The ODTX testing can also provide useful data for assessing the thermal explosion violence of energetic materials. This report summarizes the recent ODTX experimental data and modeling results for 2,6-diamino-3,5-dintropyrazine (ANPZ).« less

  13. Resource recycling technique of abandoned TNT-RDX-AL mixed explosive

    NASA Astrophysics Data System (ADS)

    Chen, Siyang; Ding, Yukui

    2017-08-01

    TNT-RDX-AL mixed explosive is a kind of high energy mixed explosive. It has the detonation characteristics even when reaching the scrapping standard. Inappropriate disposal often causes serious accident. Employing the resource recycling technique, the abandoned TNT-RDX-AL mixed explosive can be recycled. This paper summarized the progress of recycling of abandoned mixed explosive. What's more, three kinds of technological process of resource recycling abandoned TNT-RDX-AL mixed explosives are introduced. The author analysis of the current recovery processes and provided a reference for the recycling of the other same type explosive.

  14. Microcantilever detector for explosives

    DOEpatents

    Thundat, Thomas G.

    1999-01-01

    Methods and apparatus for detecting the presence of explosives by analyzing a vapor sample from the suspect vicinity utilize at least one microcantilever. Explosive gas molecules which have been adsorbed onto the microcantilever are subsequently heated to cause combustion. Heat, along with momentum transfer from combustion, causes bending and a transient resonance response of the microcantilever which may be detected by a laser diode which is focused on the microcantilever and a photodetector which detects deflection of the reflected laser beam caused by heat-induced deflection and resonance response of the microcantilever.

  15. Laser initiation of explosives

    NASA Astrophysics Data System (ADS)

    Singh, Manpreet; Sethi, V. S.

    2002-09-01

    Through laser initiation of explosives offers many advantages like controlled threshold energy over wide range, replacement of complicated safety arming mechanisms to simple and better system, immunity to RF/EMI environment etc, but there is greater difficulty to build detonator for all purpose applications and regular field trials. The challenges are to understand the interaction of laser radiation or its induced plasma with explosives, launching and transmission of high power laser beam, coupling and focussing to desired target area. This paper looks into the details of those facts.

  16. Microcantilever detector for explosives

    DOEpatents

    Thundat, T.G.

    1999-06-29

    Methods and apparatus for detecting the presence of explosives by analyzing a vapor sample from the suspect vicinity utilize at least one microcantilever. Explosive gas molecules which have been adsorbed onto the microcantilever are subsequently heated to cause combustion. Heat, along with momentum transfer from combustion, causes bending and a transient resonance response of the microcantilever which may be detected by a laser diode which is focused on the microcantilever and a photodetector which detects deflection of the reflected laser beam caused by heat-induced deflection and resonance response of the microcantilever. 2 figs.

  17. Method for digesting a nitro-bearing explosive compound

    DOEpatents

    Shah, Manish M.

    2000-01-01

    The present invention is a process wherein superoxide radicals from superoxide salt are used to break down the explosive compounds. The process has an excellent reaction rate for degrading explosives, and operates at ambient temperature and atmospheric pressure in aqueous or non-aqueous conditions. Because the superoxide molecules are small, much smaller than an enzyme molecule for example, they can penetrate the microstructure of plastic explosives faster. The superoxide salt generates reactive hydroxyl radicals, which can destroy other organic contaminants, if necessary, along with digesting the explosive nitro-bearing compound.

  18. Explosive activity associated with the growth of volcanic domes

    USGS Publications Warehouse

    Newhall, C.G.; Melson, W.G.

    1983-01-01

    Domes offer unique opportunities to measure or infer the characteristics of magmas that, at domes and elsewhere, control explosive activity. A review of explosive activity associated with historical dome growth shows that: 1. (1) explosive activity has occurred in close association with nearly all historical dome growth; 2. (2) whole-rock SiO2 content, a crude but widely reported indicator of magma viscosity, shows no systematic relationship to the timing and character of explosions; 3. (3) the average rate of dome growth, a crude indicator of the rate of supply of magma and volatiles to the near-surface enviornment, shows no systematic relationship to the timing or character of explosions; and 4. (4) new studies at Arenal and Mount St. Helens suggest that water content is the dominant control on explosions from water-rich magmas, whereas the crystal content and composition of the interstitial melt (and hence magma viscosity) are equally or more important controls on explosions from water-poor magmas. New efforts should be made to improve current, rather limited techniques for monitoring pre-eruption volatile content and magma viscosity, and thus the explosive potential of magmas. ?? 1983.

  19. Relationship between pressure and reaction violence in thermal explosions

    NASA Astrophysics Data System (ADS)

    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.

  20. 78 FR 64246 - Commerce in Explosives; List of Explosives Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-28

    ... [2,2-dinitropropyl acrylate]. DNPD [dinitropentano nitrile]. Dynamite. E EDDN [ethylene diamine dinitrate]. EDNA [ethylenedinitramine]. Ednatol. EDNP [ethyl 4,4-dinitropentanoate]. EGDN [ethylene glycol.... Nitroglycol [ethylene glycol dinitrate, EGDN]. Nitroguanidine explosives. Nitronium perchlorate propellant...

  1. Scaled experiments of explosions in cavities

    DOE PAGES

    Grun, J.; Cranch, G. A.; Lunsford, R.; ...

    2016-05-11

    Consequences of an explosion inside an air-filled cavity under the earth's surface are partly duplicated in a laboratory experiment on spatial scales 1000 smaller. The experiment measures shock pressures coupled into a block of material by an explosion inside a gas-filled cavity therein. The explosion is generated by suddenly heating a thin foil that is located near the cavity center with a short laser pulse, which turns the foil into expanding plasma, most of whose energy drives a blast wave in the cavity gas. Variables in the experiment are the cavity radius and explosion energy. Measurements and GEODYN code simulationsmore » show that shock pressuresmeasured in the block exhibit a weak dependence on scaled cavity radius up to ~25 m/kt 1/3, above which they decrease rapidly. Possible mechanisms giving rise to this behavior are described. As a result, the applicability of this work to validating codes used to simulate full-scale cavityexplosions is discussed.« less

  2. 36 CFR § 520.15 - Weapons and explosives.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Weapons and explosives. § 520... § 520.15 Weapons and explosives. No person while on the premises shall carry firearms, other dangerous or deadly weapons, or explosives, either openly or concealed, except for official purposes, nor shall...

  3. 29 CFR 1910.109 - Explosives and blasting agents.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... devices. Examples of explosive-actuated power devices are jet tappers and jet perforators. (3) Explosive... more magazines, as a group, must be considered as one magazine, and the total quantity of explosives... located in the same building when one is used only for blasting caps in quantities not in excess of 5,000...

  4. 29 CFR 1910.109 - Explosives and blasting agents.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... devices. Examples of explosive-actuated power devices are jet tappers and jet perforators. (3) Explosive... more magazines, as a group, must be considered as one magazine, and the total quantity of explosives... located in the same building when one is used only for blasting caps in quantities not in excess of 5,000...

  5. 29 CFR 1910.109 - Explosives and blasting agents.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... devices. Examples of explosive-actuated power devices are jet tappers and jet perforators. (3) Explosive... more magazines, as a group, must be considered as one magazine, and the total quantity of explosives... located in the same building when one is used only for blasting caps in quantities not in excess of 5,000...

  6. The Expansion of Explosives Safety Education for the 21st Century

    DTIC Science & Technology

    2010-07-01

    shape charges, explosive welding, thermite reaction – Sensitivity testing: drop hammer, electrospark discharge, friction – Physics of explosives, history... ATF ) • Phytoremediation workers use plants to remove explosives from soil and render the explosives harmless • Sales of explosives detection

  7. Explosion characteristics of flammable organic vapors in nitrous oxide atmosphere.

    PubMed

    Koshiba, Yusuke; Takigawa, Tomihisa; Matsuoka, Yusaku; Ohtani, Hideo

    2010-11-15

    Despite unexpected explosion accidents caused by nitrous oxide have occurred, few systematic studies have been reported on explosion characteristics of flammable gases in nitrous oxide atmosphere compared to those in air or oxygen. The objective of this paper is to characterize explosion properties of mixtures of n-pentane, diethyl ether, diethylamine, or n-butyraldehyde with nitrous oxide and nitrogen using three parameters: explosion limit, peak explosion pressure, and time to the peak explosion pressure. Then, similar mixtures of n-pentane, diethyl ether, diethylamine, or n-butyraldehyde with oxygen and nitrogen were prepared to compare their explosion characteristics with the mixtures containing nitrous oxide. The explosion experiments were performed in a cylindrical vessel at atmospheric pressure and room temperature. The measurements showed that explosion ranges of the mixtures containing nitrous oxide were narrow compared to those of the mixtures containing oxygen. On the other hand, the maximum explosion pressures of the mixtures containing nitrous oxide were higher than those of the mixtures containing oxygen. Moreover, our experiments revealed that these mixtures differed in equivalence ratios at which the maximum explosion pressures were observed: the pressures of the mixtures containing nitrous oxide were observed at stoichiometry; in contrast, those of the mixtures containing oxygen were found at fuel-rich area. Chemical equilibrium calculations confirmed these behaviors. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. Multi-scale fracture damage associated with underground chemical explosions

    NASA Astrophysics Data System (ADS)

    Swanson, E. M.; Sussman, A. J.; Wilson, J. E.; Townsend, M. J.; Prothro, L. B.; Gang, H. E.

    2018-05-01

    Understanding rock damage induced by explosions is critical for a number of applications including the monitoring and verification of underground nuclear explosions, mine safety issues, and modeling fluid flow through fractured rock. We use core observations, televiewer logs, and thin section observations to investigate fracture damage associated with two successive underground chemical explosions (SPE2 and SPE3) in granitic rock at both the mesoscale and microscale. We compare the frequency and orientations of core-scale fractures, and the frequency of microfractures, between a pre-experiment core and three post-experiment cores. Natural fault zones and explosion-induced fractures in the vicinity of the explosive source are readily apparent in recovered core and in thin sections. Damage from faults and explosions is not always apparent in fracture frequency plots from televiewer logs, although orientation data from these logs suggests explosion-induced fracturing may not align with the pre-existing fracture sets. Core-scale observations indicate the extent of explosion-induced damage is 10.0 m after SPE2 and 6.8 m after SPE3, despite both a similar size and location for both explosions. At the microscale, damage is observed to a range distance of 10.2 ± 0.9 m after SPE2, and 16.6 ± 0.9 and 11.2 ± 0.6 in two different cores collected after SPE3. Additional explosion-induced damage, interpreted to be the result of spalling, is readily apparent near the surface, but only in the microfracture data. This depth extent and intensity of damage in the near-surface region also increased after an additional explosion. This study highlights the importance of evaluating structural damage at multiple scales for a more complete characterization of the damage, and particularly shows the importance of microscale observations for identifying spallation-induced damage.

  9. Multi-scale fracture damage associated with underground chemical explosions

    DOE PAGES

    Swanson, Erika M.; Sussman, A. J.; Wilson, J. E.; ...

    2018-02-22

    Understanding rock damage induced by explosions is critical for a number of applications including the monitoring and verification of underground nuclear explosions, mine safety issues, and modeling fluid flow through fractured rock. We use core observations, televiewer logs, and thin section observations to investigate fracture damage associated with two successive underground chemical explosions (SPE2 and SPE3) in granitic rock at both the mesoscale and microscale. We compare the frequency and orientations of core-scale fractures, and the frequency of microfractures, between a pre-experiment core and three post-experiment cores. Natural fault zones and explosion-induced fractures in the vicinity of the explosive sourcemore » are readily apparent in recovered core and in thin sections. Damage from faults and explosions is not always apparent in fracture frequency plots from televiewer logs, although orientation data from these logs suggests explosion-induced fracturing may not align with the pre-existing fracture sets. Core-scale observations indicate the extent of explosion-induced damage is 10.0 m after SPE2 and 6.8 m after SPE3, despite both a similar size and location for both explosions. At the microscale, damage is observed to a range distance of 10.2 ± 0.9 m after SPE2, and 16.6 ± 0.9 and 11.2 ± 0.6 in two different cores collected after SPE3. Additional explosion-induced damage, interpreted to be the result of spalling, is readily apparent near the surface, but only in the microfracture data. This depth extent and intensity of damage in the near-surface region also increased after an additional explosion. This study highlights the importance of evaluating structural damage at multiple scales for a more complete characterization of the damage, and particularly shows the importance of microscale observations for identifying spallation-induced damage.« less

  10. Multi-scale fracture damage associated with underground chemical explosions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Swanson, Erika M.; Sussman, A. J.; Wilson, J. E.

    Understanding rock damage induced by explosions is critical for a number of applications including the monitoring and verification of underground nuclear explosions, mine safety issues, and modeling fluid flow through fractured rock. We use core observations, televiewer logs, and thin section observations to investigate fracture damage associated with two successive underground chemical explosions (SPE2 and SPE3) in granitic rock at both the mesoscale and microscale. We compare the frequency and orientations of core-scale fractures, and the frequency of microfractures, between a pre-experiment core and three post-experiment cores. Natural fault zones and explosion-induced fractures in the vicinity of the explosive sourcemore » are readily apparent in recovered core and in thin sections. Damage from faults and explosions is not always apparent in fracture frequency plots from televiewer logs, although orientation data from these logs suggests explosion-induced fracturing may not align with the pre-existing fracture sets. Core-scale observations indicate the extent of explosion-induced damage is 10.0 m after SPE2 and 6.8 m after SPE3, despite both a similar size and location for both explosions. At the microscale, damage is observed to a range distance of 10.2 ± 0.9 m after SPE2, and 16.6 ± 0.9 and 11.2 ± 0.6 in two different cores collected after SPE3. Additional explosion-induced damage, interpreted to be the result of spalling, is readily apparent near the surface, but only in the microfracture data. This depth extent and intensity of damage in the near-surface region also increased after an additional explosion. This study highlights the importance of evaluating structural damage at multiple scales for a more complete characterization of the damage, and particularly shows the importance of microscale observations for identifying spallation-induced damage.« less

  11. Pacemaker explosions in crematoria: problems and possible solutions

    PubMed Central

    Gale, Christopher P; Mulley, Graham P

    2002-01-01

    The number of artificial cardiac pacemakers is increasing, as is the number of bodies being cremated. Because of the explosive potential of pacemakers when heated, a statutory question on the cremation form asks whether the deceased has a pacemaker and if so whether it has been removed. We sent a questionnaire to all the crematoria in the UK enquiring about the frequency, consequences and prevention of pacemaker explosions. We found that about half of all crematoria in the UK experience pacemaker explosions, that pacemaker explosions may cause structural damage and injury and that most crematoria staff are unaware of the explosive potential of implantable cardiac defibrillators. Crematoria staff rely on the accurate completion of cremation forms, and doctors who sign cremation forms have a legal obligation to provide such information. PMID:12091510

  12. Adaptive radiation versus 'radiation' and 'explosive diversification': why conceptual distinctions are fundamental to understanding evolution.

    PubMed

    Givnish, Thomas J

    2015-07-01

    Adaptive radiation is the rise of a diversity of ecological roles and role-specific adaptations within a lineage. Recently, some researchers have begun to use 'adaptive radiation' or 'radiation' as synonymous with 'explosive species diversification'. This essay aims to clarify distinctions between these concepts, and the related ideas of geographic speciation, sexual selection, key innovations, key landscapes and ecological keys. Several examples are given to demonstrate that adaptive radiation and explosive diversification are not the same phenomenon, and that focusing on explosive diversification and the analysis of phylogenetic topology ignores much of the rich biology associated with adaptive radiation, and risks generating confusion about the nature of the evolutionary forces driving species diversification. Some 'radiations' involve bursts of geographic speciation or sexual selection, rather than adaptive diversification; some adaptive radiations have little or no effect on speciation, or even a negative effect. Many classic examples of 'adaptive radiation' appear to involve effects driven partly by geographic speciation, species' dispersal abilities, and the nature of extrinsic dispersal barriers; partly by sexual selection; and partly by adaptive radiation in the classical sense, including the origin of traits and invasion of adaptive zones that result in decreased diversification rates but add to overall diversity. © 2015 The Author. New Phytologist © 2015 New Phytologist Trust.

  13. DoD Contractors’ Safety Manual for Ammunition and Explosives.

    DTIC Science & Technology

    1997-09-01

    grit, and other foreign material into operating buildings. 9. Windows and skylights . Non-shatterable glazing is preferred where an explosion...with the explosives being processed. Dull or damaged tools shall not be used for machining high explosives. k. The explosives products resulting from

  14. Explosion characteristics of LPG-air mixtures in closed vessels.

    PubMed

    Razus, Domnina; Brinzea, Venera; Mitu, Maria; Oancea, D

    2009-06-15

    The experimental study of explosive combustion of LPG (liquefied petroleum gas)-air mixtures at ambient initial temperature was performed in two closed vessels with central ignition, at various total initial pressures within 0.3-1.3bar and various fuel/air ratios, within the flammability limits. The transient pressure-time records were used to determine several explosion characteristics of LPG-air: the peak explosion pressure, the explosion time (the time necessary to reach the peak pressure), the maximum rate of pressure rise and the severity factor. All explosion parameters are strongly dependent on initial pressure of fuel-air mixture and on fuel/air ratio. The explosion characteristics of LPG-air mixtures are discussed in comparison with data referring to the main components of LPG: propane and butane, obtained in identical conditions.

  15. Evolutionary Engineering Improves Tolerance for Replacement Jet Fuels in Saccharomyces cerevisiae

    PubMed Central

    Brennan, Timothy C. R.; Williams, Thomas C.; Schulz, Benjamin L.; Palfreyman, Robin W.; Nielsen, Lars K.

    2015-01-01

    Monoterpenes are liquid hydrocarbons with applications ranging from flavor and fragrance to replacement jet fuel. Their toxicity, however, presents a major challenge for microbial synthesis. Here we evolved limonene-tolerant Saccharomyces cerevisiae strains and sequenced six strains across the 200-generation evolutionary time course. Mutations were found in the tricalbin proteins Tcb2p and Tcb3p. Genomic reconstruction in the parent strain showed that truncation of a single protein (tTcb3p1-989), but not its complete deletion, was sufficient to recover the evolved phenotype improving limonene fitness 9-fold. tTcb3p1-989 increased tolerance toward two other monoterpenes (β-pinene and myrcene) 11- and 8-fold, respectively, and tolerance toward the biojet fuel blend AMJ-700t (10% cymene, 50% limonene, 40% farnesene) 4-fold. tTcb3p1-989 is the first example of successful engineering of phase tolerance and creates opportunities for production of the highly toxic C10 alkenes in yeast. PMID:25746998

  16. Effect of Crystallizable Solvent on Phase Separation and Charge Transport in Polymer-fullerene Films

    NASA Astrophysics Data System (ADS)

    Kaewprajak, A.; Lohawet, K.; Wutikhun, T.; Meemuk, B.; Kumnorkaew, P.; Sagawa, T.

    2017-09-01

    The effect of 1,3,5-trichlorobenzene (TCB) as crystallizable solvent on poly[N-9‧-heptadecanyl-2,7-carbazole-alt-5,5-(4‧,7‧-di-2-thienyl-2‧,1‧,3‧-benzothiadiazole)] (PCDTBT) and [6,6]-phenyl C71 butyric acid methyl ester (PC71BM) bulk heterojunction (BHJ) was investigated. We found that phase separation of PCDTBT and PC71BM and formation of the condensed network of polymers were appropriately regulated by addition of TCB in the BHJ films, which were confirmed by optical microscopic, AFM, and TEM observations in addition to current-voltage analyses. Through the formation of a good continuous pathway for carrier transport by the addition of TCB, 2.5 times enhancement of the hole mobility in the BHJ film was attained from 5.82 × 10-5 cm2 V-1 s-1 without TCB to 1.48 × 10-4 cm2 V-1 s-1 with 20 mg ml-1 of TCB.

  17. 30 CFR 56.6102 - Explosive material storage practices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Explosive material storage practices. 56.6102 Section 56.6102 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Storage § 56.6102 Explosive material storag...

  18. 30 CFR 56.6102 - Explosive material storage practices.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Explosive material storage practices. 56.6102 Section 56.6102 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Storage § 56.6102 Explosive material storag...

  19. 30 CFR 56.6102 - Explosive material storage practices.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Explosive material storage practices. 56.6102 Section 56.6102 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Storage § 56.6102 Explosive material storag...

  20. 33 CFR 401.67 - Explosive vessels.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Dangerous Cargo § 401.67 Explosive vessels. A vessel carrying explosives, either Government or commercial, as defined in the Dangerous Cargo Act of the United States and in the International Maritime Dangerous Goods Code, Class 1, Divisions 1.1 to 1.5 inclusive...

  1. 33 CFR 401.67 - Explosive vessels.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Dangerous Cargo § 401.67 Explosive vessels. A vessel carrying explosives, either Government or commercial, as defined in the Dangerous Cargo Act of the United States and in the International Maritime Dangerous Goods Code, Class 1, Divisions 1.1 to 1.5 inclusive...

  2. 33 CFR 401.67 - Explosive vessels.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Dangerous Cargo § 401.67 Explosive vessels. A vessel carrying explosives, either Government or commercial, as defined in the Dangerous Cargo Act of the United States and in the International Maritime Dangerous Goods Code, Class 1, Divisions 1.1 to 1.5 inclusive...

  3. Explosive Joining for Nuclear-Reactor Repair

    NASA Technical Reports Server (NTRS)

    Bement, L. J.; Bailey, J. W.

    1983-01-01

    In explosive joining technique, adapter flange from fuel channel machined to incorporate a V-notch interface. Ribbon explosive, 1/2 inch (1.3 cm) in width, drives V-notched wall of adapter into bellows assembly, producing atomic-level metallurgical bond. Ribbon charge yields joint with double parent metal strength.

  4. Explaining the morphology of supernova remnant (SNR) 1987A with the jittering jets explosion mechanism

    NASA Astrophysics Data System (ADS)

    Bear, Ealeal; Soker, Noam

    2018-07-01

    We find that the remnant of supernova (SN) 1987A shares some morphological features with four supernova remnants (SNRs) that have signatures of shaping by jets, and from that we strengthen the claim that jets played a crucial role in the explosion of SN 1987A. Some of the morphological features appear also in planetary nebulae (PNe) where jets are observed. The clumpy ejecta brings us to support the claim that the jittering jets explosion mechanism can account for the structure of the remnant of SN 1987A, i.e. SNR 1987A. We conduct a preliminary attempt to quantify the fluctuations in the angular momentum of the mass that is accreted on to the newly born neutron star via an accretion disc or belt. The accretion disc/belt launches jets that explode core collapse supernovae (CCSNe). The relaxation time of the accretion disc/belt is comparable to the duration of a typicalfigu jet-launching episode in the jittering jets explosion mechanism, and hence the disc/belt has no time to relax. We suggest that this might explain the two unequal opposite jets that later lead to the unequal sides of the elongated structures in some SNRs of CCSNe. We reiterate our earlier call for a paradigm shift from a neutrino-driven explosion to a jet-driven explosion of CCSNe.

  5. Explaining the morphology of supernova remnant (SNR) 1987A with the jittering jets explosion mechanism

    NASA Astrophysics Data System (ADS)

    Bear, Ealeal; Soker, Noam

    2018-04-01

    We find that the remnant of supernova (SN) 1987A shares some morphological features with four supernova remnants (SNRs) that have signatures of shaping by jets, and from that we strengthen the claim that jets played a crucial role in the explosion of SN 1987A. Some of the morphological features appear also in planetary nebulae (PNe) where jets are observed. The clumpy ejecta bring us to support the claim that the jittering jets explosion mechanism can account for the structure of the remnant of SN 1987A, i.e., SNR 1987A. We conduct a preliminary attempt to quantify the fluctuations in the angular momentum of the mass that is accreted on to the newly born neutron star via an accretion disk or belt. The accretion disk/belt launches the jets that explode core collapse supernovae (CCSNe). The relaxation time of the accretion disk/belt is comparable to the duration of a typical jet-launching episode in the jittering jets explosion mechanism, and hence the disk/belt has no time to relax. We suggest that this might explain two unequal opposite jets that later lead to unequal sides of the elongated structures in some SNRs of CCSNe. We reiterate our earlier call for a paradigm shift from neutrino-driven explosion to a jet-driven explosion of CCSNe.

  6. Shock Initiated Reactions of Reactive Multiphase Blast Explosives

    NASA Astrophysics Data System (ADS)

    Wilson, Dennis; Granier, John; Johnson, Richard; Littrell, Donald

    2015-06-01

    This paper describes a new class of reactive multiphase blast explosives (RMBX) and characterization of their blast characteristics. These RMBXs are non-ideal explosive compositions of perfluoropolyether (PFPE), nano aluminum, and a micron-size high-density reactive metal - Tantalum, Zirconium, or Zinc in mass loadings of 66 to 83 percent. Unlike high explosives, these PFPE-metal compositions release energy via a fast self-oxidized combustion wave (rather than a true self-sustaining detonation) that is shock dependent, and can be overdriven to control energy release rate. The term ``reactive multiphase blast'' refers to the post-dispersion blast behavior: multiphase in that there are a gas phase that imparts pressure and a solid (particulate) phase that imparts momentum; and reactive in that the hot metal particles react with atmospheric oxygen and the explosive gas products to give an extended pressure pulse. The RMBX formulations were tested in two spherical core-shell geometries - an RMBX shell exploded by a high explosive core, and an RMBX core imploded by a high explosive shell. The fireball and blast characteristics were compared to a C-4 baseline charge.

  7. Surface Instabilities From Buried Explosives

    DTIC Science & Technology

    2009-07-21

    interface between soil and air during buried explosions. The purpose of understanding this instability is to determine its effect on local vehicle loading...Except when the target is on the surface, e.g., a tank track, the most important loading mechanism from a buried charge is the impact of soil propelled...rising soil and the air. This unstable 15. SUBJECT TERMS Buried Explosions, Richtmyer-Meshkov Instability, Target Loading, Jetting, 16 SECURITY

  8. System for analysis of explosives

    DOEpatents

    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.

  9. Damage-Sensitivity Correlations in Explosives

    DTIC Science & Technology

    2014-07-25

    matrix material” • “Friction between sliding or impacting surfaces, or between explosive crystals and/or grit particles in an explosive...particulates • Viscoelastic dissipation in binder temperature rise • Grain -matrix debonding, binder tearing damage • Grain - grain contact fracture and...DISTRIBUTION STATEMENT A – Unlimited Distribution. Case Number: 96ABW-2013-0209, 9 August 2013 3 Voids and Defects Cracked Crystals Crystal - Crystal

  10. Method of digesting an explosive nitro compound

    DOEpatents

    Shah, Manish M.

    2000-01-01

    The present invention is a process wherein bleaching oxidants are used to digest explosive nitro compounds. The process has an excellent reaction rate for digesting explosives and operates under multivariate conditions. Reaction solutions may be aqueous, non-aqueous or a combination thereof, and can also be any pH, but preferably have a pH between 2 and 9. The temperature may be ambient as well as any temperature above which freezing of the solution would occur and below which any degradation of the bleaching oxidant would occur or below which any explosive reaction would be initiated. The pressure may be any pressure, but is preferably ambient or atmospheric, or a pressure above a vapor pressure of the aqueous solution to avoid boiling of the solution. Because the bleaching oxidant molecules are small, much smaller than an enzyme molecule for example, they can penetrate the microstructure of plastic explosives faster. The bleaching oxidants generate reactive hydroxyl radicals, which can destroy other organic contaminants, if necessary, along with digesting the explosive nitro compound.

  11. Anatomy of a diffracting detonation in a circular arc of explosive

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bdzil, John Bohdan

    Using high-resolution numerical simulation, study diffraction of a detonation as it traverses a 270° finite-thickness condensed-phase explosive arc. This geometry admits a steady solution in a frame rotating with angular speed ω 0, which thereby facilitates a detailed analysis of how the loss of energy from the detonation reaction zone due to the diffraction process slows the propagation of the detonation. There exists a region of subsonic flow, between the detonation shock and the curve of sonic flow (labelled the DDZ), which is responsible for setting ω 0. Although the DDZ spans the entire thickness for thin arcs, it ismore » localized to a region near the inside surface as the arc is thickened. Furthermore the explosive energy release near this inside surface plays a disproportionate role in the diffraction process.« less

  12. Anatomy of a diffracting detonation in a circular arc of explosive

    DOE PAGES

    Bdzil, John Bohdan

    2018-02-08

    Using high-resolution numerical simulation, study diffraction of a detonation as it traverses a 270° finite-thickness condensed-phase explosive arc. This geometry admits a steady solution in a frame rotating with angular speed ω 0, which thereby facilitates a detailed analysis of how the loss of energy from the detonation reaction zone due to the diffraction process slows the propagation of the detonation. There exists a region of subsonic flow, between the detonation shock and the curve of sonic flow (labelled the DDZ), which is responsible for setting ω 0. Although the DDZ spans the entire thickness for thin arcs, it ismore » localized to a region near the inside surface as the arc is thickened. Furthermore the explosive energy release near this inside surface plays a disproportionate role in the diffraction process.« less

  13. Different kinetic pathways of the binding of two biphenyl analogues of colchicine to tubulin.

    PubMed

    Dumortier, C; Gorbunoff, M J; Andreu, J M; Engelborghs, Y

    1996-04-09

    The kinetics of the interaction of tubulin with two biphenyl analogues of colchicine were measured by fluorescence stopped flow. The ligands were 2,3,4-trimethoxy-4'-carbomethoxy-1,1'-biphenyl (TCB) and 2,3,4-trimethoxy-4'-acetyl-1,1'-biphenyl (TKB). The binding of both analogues is accompanied by a fluorescence increase with monophasic kinetics, which indicates that these drugs, unlike colchicine, do not discriminate between the isoforms of tubulin. The observed pseudo-first-order rate constant increases in a nonlinear way with the drug concentration, indicating that the binding of the biphenyl analogues to tubulin occurs, like colchicine, in two steps: a fast reversible equilibrium followed by an isomerization of the initial complex. Kinetic analysis shows that TCB and TKB exhibit differences in their K1 values. At 25 degrees C, these are 114,000 +/- 15,000 M(-1) for TCB and 8,300 +/- 900 M(-1) for TKB. Both molecules show a much higher affinity than colchicine for the initial binding site. Also at 25 degrees C, the k2 value is 0.66 +/- 0.04 s(-1) for TCB and 3.0 +/- 0.2 s(-1) for TKB. From the temperature dependence, a reaction enthalpy change for the initial binding (deltaH(zero)1) of 44 +/- 9 kJ x mol(-1) (TCB) and -40 +/- 14 kJ x mol(-1) (TKB) and an activation energy for the second forward step of 64 +/- 2 kJ x mol(-1) (TCB) and 101 +/- 10 kJ x mol(-1) (TKB) were calculated. The dissociation kinetics were studied by displacement experiments, in which podophyllotoxin was used as a displacing ligand. The rate constant for the second step in the off direction (k(-2)) is 0.25 +/- 0.05 s(-1) for TCB and 0.093 +/- 0.009 s(-1) for TKB at 25 degrees C. The activation energies for the backward isomerization of the complexes were found to be 86 +/- 20 kJ x mol(-1) (TCB) and 79 +/- 5 kJ x mol(-1) (TKB). Combination of these results with the kinetic parameters for association gives a full characterization of the enthalpy pathway for the binding of TCB and TKB. The

  14. Source spectral variation and yield estimation for small, near-source explosions

    NASA Astrophysics Data System (ADS)

    Yoo, S.; Mayeda, K. M.

    2012-12-01

    Significant S-wave generation is always observed from explosion sources which can lead to difficulty in discriminating explosions from natural earthquakes. While there are numerous S-wave generation mechanisms that are currently the topic of significant research, the mechanisms all remain controversial and appear to be dependent upon the near-source emplacement conditions of that particular explosion. To better understand the generation and partitioning of the P and S waves from explosion sources and to enhance the identification and discrimination capability of explosions, we investigate near-source explosion data sets from the 2008 New England Damage Experiment (NEDE), the Humble-Redwood (HR) series of explosions, and a Massachusetts quarry explosion experiment. We estimate source spectra and characteristic source parameters using moment tensor inversions, direct P and S waves multi-taper analysis, and improved coda spectral analysis using high quality waveform records from explosions from a variety of emplacement conditions (e.g., slow/fast burning explosive, fully tamped, partially tamped, single/ripple-fired, and below/above ground explosions). The results from direct and coda waves are compared to theoretical explosion source model predictions. These well-instrumented experiments provide us with excellent data from which to document the characteristic spectral shape, relative partitioning between P and S-waves, and amplitude/yield dependence as a function of HOB/DOB. The final goal of this study is to populate a comprehensive seismic source reference database for small yield explosions based on the results and to improve nuclear explosion monitoring capability.

  15. Morphologically manipulated Ag/ZnO nanostructures as surface enhanced Raman scattering probes for explosives detection

    NASA Astrophysics Data System (ADS)

    Shaik, Ummar Pasha; Hamad, Syed; Ahamad Mohiddon, Md.; Soma, Venugopal Rao; Ghanashyam Krishna, M.

    2016-03-01

    The detection of secondary explosive molecules (e.g., ANTA, FOX-7, and CL-20) using Ag decorated ZnO nanostructures as surface enhanced Raman scattering (SERS) probes is demonstrated. ZnO nanostructures were grown on borosilicate glass substrates by rapid thermal oxidation of metallic Zn films at 500 °C. The oxide nanostructures, including nanosheets and nanowires, emerged over the surface of the Zn film leaving behind the metal residue. We demonstrate that SERS measurements with concentrations as low as 10 μM, of the three explosive molecules ANTA, FOX-7, and CL-20 over ZnO/Ag nanostructures, resulted in enhancement factors of ˜107, ˜107, and ˜104, respectively. These measurements validate the high sensitivity of detection of explosive molecules using Ag decorated ZnO nanostructures as SERS substrates. The Zn metal residue and conditions of annealing play an important role in determining the detection sensitivity.

  16. Spectroscopic characterization of nitroaromatic landmine signature explosives

    NASA Astrophysics Data System (ADS)

    Hernandez-Rivera, Samuel P.; Manrique-Bastidas, Cesar A.; Blanco, Alejandro; Primera, Oliva M.; Pacheco, Leonardo C.; Castillo-Chara, Jairo; Castro, Miguel E.; Mina, Nairmen

    2004-09-01

    TNT and DNT are important explosives used as base charges of landmines and other explosive devices. They are often combined with RDX in specific explosive formulations. Their detection in vapor phase as well as in soil in contact with the explosives is important in landmine detection technology. The spectroscopic signatures of nitroaromatic compounds in neat forms: crystals, droplets, and recrystallized samples were determined by Raman Microspectroscopy (RS), Fourier Transform Infrared Microscopy (FTIR) and Fiber Optics Coupled - Fourier Transform Infrared Spectroscopy (FOC-FTIR) using a grazing angle (GA) probe. TNT exhibits a series of characteristic bands: vibrational signatures, which allow its detection in soil. The spectroscopic signature of neat TNT is dominated by strong bands about 1380 and 2970 cm-1. The intensity and position of these bands were found remarkably different in soil samples spiked with TNT. The 1380 cm-1 band is split into a number of bands in that region. The 2970 cm-1 band is reduced in intensity and new bands are observed about 2880 cm-1. The results are consistent with a different chemical environment of TNT in soil as compared to neat TNT. Interactions were found to be dependent on the physical source of the explosive. In the case of DNT-sand interactions, shifts in vibrational frequencies of the explosives as well as the substrates were found.

  17. Metal explosion chambers: designing, manufacturing, application

    NASA Astrophysics Data System (ADS)

    Stoyanovskii, O. I.; Zlobin, B. S.; Shtertser, A. A.; Meshcheryakov, Y. P.

    2017-10-01

    Designing of explosion chambers is based on research investigations of the chamber body stress-strain state, which is determined by numerical computation and experimentally by the strain gage technique. Studies show that chamber bottoms are the most loaded elements, and maximal stresses arise in chamber poles. Increasing the shell thickness around poles by welding-in an insert is a simple and saving way to solve this problem. There are structural solutions, enabling reliable hermetic closure and preventing leakage of detonation products from the chamber. Explosion chambers are employed in scientific research and in different industrial applications: explosive welding and hardening, synthesis of new materials, disposal of expired ammunition, and etc.

  18. Explosive genetic evidence for explosive human population growth

    PubMed Central

    Gao, Feng; Keinan, Alon

    2016-01-01

    The advent of next-generation sequencing technology has allowed the collection of vast amounts of genetic variation data. A recurring discovery from studying larger and larger samples of individuals had been the extreme, previously unexpected, excess of very rare genetic variants, which has been shown to be mostly due to the recent explosive growth of human populations. Here, we review recent literature that inferred recent changes in population size in different human populations and with different methodologies, with many pointing to recent explosive growth, especially in European populations for which more data has been available. We also review the state-of-the-art methods and software for the inference of historical population size changes that lead to these discoveries. Finally, we discuss the implications of recent population growth on personalized genomics, on purifying selection in the non-equilibrium state it entails and, as a consequence, on the genetic architecture underlying complex disease and the performance of mapping methods in discovering rare variants that contribute to complex disease risk. PMID:27710906

  19. The Role of the Stratosphere in Explosive Deepening of Extratropical Cyclones

    NASA Astrophysics Data System (ADS)

    Knippertz, Peter; Wilbraham, Robert; Trzeciak, Tomek; Owen, Jenny; Odell, Luke; Fink, Andreas H.; Pinto, Joaquim G.

    2014-05-01

    Using a combination of an automatic cyclone tracking method and a special version of the classical pressure tendency equation (PTE), changes in surface core pressure of extra-tropical cyclones can be related to contributions from horizontal temperature advection, vertical motion and diabatic processes, i.e. mainly latent heat release in clouds. Here, the PTE is evaluated in 3°x3° boxes located over the cyclone positions at 6-hourly basis, thus following the movement of a given storm at each time step. PTE calculations are performed from the surface to 100 hPa. Previous work has shown that this approach can be used to quantify the contribution of diabatic processes to cyclone deepening in an automated way, and can easily be applied to large gridded datasets, in this case ERA-Interim reanalyses. In order to close the mass budget in the PTE, geopotential height tendencies at the upper integration boundary (usually 100 hPa) need to be taken into account. Older studies have assumed this term to be negligible, and this has been confirmed with modern re-analysis data for many explosively deepening storms. However, some historical storms show a remarkable contribution from this term, indicating a substantial warming of the levels above 100hPa. An outstanding example is the Braer Storm of January 1993, which reached a record minimum core pressure of 914 hPa near Iceland. A stepwise increase of the upper integration boundary reveals that substantial geopotential height tendencies reach above 1 hPa. This unusual behaviour appears to be related to the propagation of a deep planetary wave trough from North America towards the North Atlantic basin. A similar but somewhat less dramatic behaviour was found for cyclone Wiebke. Another interesting example is storm Emma, which managed to sustain substantial deepening rates despite adverse positive geopotential height tendencies at 100 hPa. Future work will include a more robust statistical analysis of this problem and a better

  20. 27 CFR 555.180 - Prohibitions relating to unmarked plastic explosives.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... unmarked plastic explosives. 555.180 Section 555.180 Alcohol, Tobacco Products, and Firearms BUREAU OF... Marking of Plastic Explosives § 555.180 Prohibitions relating to unmarked plastic explosives. (a) No person shall manufacture any plastic explosive that does not contain a detection agent. (b) No person...

  1. Advancing Explosives Detection Capabilities: Vapor Detection

    ScienceCinema

    Atkinson, David

    2018-05-11

    A new, PNNL-developed method provides direct, real-time detection of trace amounts of explosives such as RDX, PETN and C-4. The method selectively ionizes a sample before passing the sample through a mass spectrometer to detect explosive vapors. The method could be used at airports to improve aviation security.

  2. 46 CFR 188.10-25 - Explosive.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Explosive. 188.10-25 Section 188.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-25 Explosive. This term means a chemical compound or...

  3. 46 CFR 188.10-25 - Explosive.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Explosive. 188.10-25 Section 188.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-25 Explosive. This term means a chemical compound or...

  4. 46 CFR 188.10-25 - Explosive.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Explosive. 188.10-25 Section 188.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-25 Explosive. This term means a chemical compound or...

  5. 46 CFR 188.10-25 - Explosive.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Explosive. 188.10-25 Section 188.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-25 Explosive. This term means a chemical compound or...

  6. 46 CFR 188.10-25 - Explosive.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Explosive. 188.10-25 Section 188.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-25 Explosive. This term means a chemical compound or...

  7. Advancing Explosives Detection Capabilities: Vapor Detection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Atkinson, David

    2012-10-15

    A new, PNNL-developed method provides direct, real-time detection of trace amounts of explosives such as RDX, PETN and C-4. The method selectively ionizes a sample before passing the sample through a mass spectrometer to detect explosive vapors. The method could be used at airports to improve aviation security.

  8. Numerical Simulations of Thermobaric Explosions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

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

    2007-05-04

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

  9. CFD analysis of gas explosions vented through relief pipes.

    PubMed

    Ferrara, G; Di Benedetto, A; Salzano, E; Russo, G

    2006-09-21

    Vent devices for gas and dust explosions are often ducted to safe locations by means of relief pipes. However, the presence of the duct increases the severity of explosion if compared to simply vented vessels (i.e. compared to cases where no duct is present). Besides, the identification of the key phenomena controlling the violence of explosion has not yet been gained. Multidimensional models coupling, mass, momentum and energy conservation equations can be valuable tools for the analysis of such complex explosion phenomena. In this work, gas explosions vented through ducts have been modelled by a two-dimensional (2D) axi-symmetric computational fluid dynamic (CFD) model based on the unsteady Reynolds Averaged Navier Stokes (RANS) approach in which the laminar, flamelet and distributed combustion models have been implemented. Numerical test have been carried out by varying ignition position, duct diameter and length. Results have evidenced that the severity of ducted explosions is mainly driven by the vigorous secondary explosion occurring in the duct (burn-up) rather than by the duct flow resistance or acoustic enhancement. Moreover, it has been found out that the burn-up affects explosion severity due to the reduction of venting rate rather than to the burning rate enhancement through turbulization.

  10. Comparative techno-economic analysis of steam explosion, dilute sulfuric acid, ammonia fiber explosion and biological pretreatments of corn stover.

    PubMed

    Baral, Nawa Raj; Shah, Ajay

    2017-05-01

    Pretreatment is required to destroy recalcitrant structure of lignocelluloses and then transform into fermentable sugars. This study assessed techno-economics of steam explosion, dilute sulfuric acid, ammonia fiber explosion and biological pretreatments, and identified bottlenecks and operational targets for process improvement. Techno-economic models of these pretreatment processes for a cellulosic biorefinery of 113.5 million liters butanol per year excluding fermentation and wastewater treatment sections were developed using a modelling software-SuperPro Designer. Experimental data of the selected pretreatment processes based on corn stover were gathered from recent publications, and used for this analysis. Estimated sugar production costs ($/kg) via steam explosion, dilute sulfuric acid, ammonia fiber explosion and biological methods were 0.43, 0.42, 0.65 and 1.41, respectively. The results suggest steam explosion and sulfuric acid pretreatment methods might be good alternatives at present state of technology and other pretreatment methods require research and development efforts to be competitive with these pretreatment methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. 27 CFR 555.180 - Prohibitions relating to unmarked plastic explosives.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... person shall manufacture any plastic explosive that does not contain a detection agent. (b) No person..., receive, or possess any plastic explosive that does not contain a detection agent. This paragraph does not... Plastic Explosives means the Convention on the Marking of Plastic Explosives for the Purposes of Detection...

  12. 27 CFR 555.180 - Prohibitions relating to unmarked plastic explosives.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... person shall manufacture any plastic explosive that does not contain a detection agent. (b) No person..., receive, or possess any plastic explosive that does not contain a detection agent. This paragraph does not... Plastic Explosives means the Convention on the Marking of Plastic Explosives for the Purposes of Detection...

  13. 27 CFR 555.180 - Prohibitions relating to unmarked plastic explosives.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... person shall manufacture any plastic explosive that does not contain a detection agent. (b) No person..., receive, or possess any plastic explosive that does not contain a detection agent. This paragraph does not... Plastic Explosives means the Convention on the Marking of Plastic Explosives for the Purposes of Detection...

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

    PubMed

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

    2014-12-01

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

  15. 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.

    PubMed

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

    2015-12-30

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

  16. Towards an Empirically Based Parametric Explosion Spectral Model

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ford, S R; Walter, W R; Ruppert, S

    2009-08-31

    Small underground nuclear explosions need to be confidently detected, identified, and characterized in regions of the world where they have never before been tested. The focus of our work is on the local and regional distances (< 2000 km) and phases (Pn, Pg, Sn, Lg) necessary to see small explosions. We are developing a parametric model of the nuclear explosion seismic source spectrum that is compatible with the earthquake-based geometrical spreading and attenuation models developed using the Magnitude Distance Amplitude Correction (MDAC) techniques (Walter and Taylor, 2002). The explosion parametric model will be particularly important in regions without any priormore » explosion data for calibration. The model is being developed using the available body of seismic data at local and regional distances for past nuclear explosions at foreign and domestic test sites. Parametric modeling is a simple and practical approach for widespread monitoring applications, prior to the capability to carry out fully deterministic modeling. The achievable goal of our parametric model development is to be able to predict observed local and regional distance seismic amplitudes for event identification and yield determination in regions with incomplete or no prior history of underground nuclear testing. The relationship between the parametric equations and the geologic and containment conditions will assist in our physical understanding of the nuclear explosion source.« less

  17. Explosive composition with group VIII metal nitroso halide getter

    DOEpatents

    Walker, Franklin E.; Wasley, Richard J.

    1982-01-01

    An improved explosive composition is disclosed and comprises a major portion of an explosive having a detonation velocity between about 1,500 and 10,000 meters per second and a minor amount of a getter additive comprising a non-explosive compound or mixture of non-explosive compounds capable of chemically reacting with free radicals or ions under shock initiation conditions of 2,000 calories/cm.sup.2 or less of energy fluence.

  18. Explosive composition with group VIII metal nitroso halide getter

    DOEpatents

    Walker, F.E.; Wasley, R.J.

    1982-06-22

    An improved explosive composition is disclosed and comprises a major portion of an explosive having a detonation velocity between about 1,500 and 10,000 meters per second and a minor amount of a getter additive comprising a non-explosive compound or mixture of non-explosive compounds capable of chemically reacting with free radicals or ions under shock initiation conditions of 2,000 calories/cm[sup 2] or less of energy fluence.

  19. An Empirical Non-TNT Approach to Launch Vehicle Explosion Modeling

    NASA Technical Reports Server (NTRS)

    Blackwood, James M.; Skinner, Troy; Richardson, Erin H.; Bangham, Michal E.

    2015-01-01

    In an effort to increase crew survivability from catastrophic explosions of Launch Vehicles (LV), a study was conducted to determine the best method for predicting LV explosion environments in the near field. After reviewing such methods as TNT equivalence, Vapor Cloud Explosion (VCE) theory, and Computational Fluid Dynamics (CFD), it was determined that the best approach for this study was to assemble all available empirical data from full scale launch vehicle explosion tests and accidents. Approximately 25 accidents or full-scale tests were found that had some amount of measured blast wave, thermal, or fragment explosion environment characteristics. Blast wave overpressure was found to be much lower in the near field than predicted by most TNT equivalence methods. Additionally, fragments tended to be larger, fewer, and slower than expected if the driving force was from a high explosive type event. In light of these discoveries, a simple model for cryogenic rocket explosions is presented. Predictions from this model encompass all known applicable full scale launch vehicle explosion data. Finally, a brief description of on-going analysis and testing to further refine the launch vehicle explosion environment is discussed.

  20. [Effects of chlorobenzene stress on seedling growth and cell division of Vicia faba].

    PubMed

    Liu, Wan; Zhou, Qixing; Li, Peijun; Sun, Tieheng; Tai, Peidong; Xu, Huaxia; Zhang, Chungui; Zhang, Hairong

    2003-04-01

    Effects of 1, 2, 4-trichlorobenzene (TCB) stress on seedling growth, cell division and chromosomal aberration frequency of root-tip cells of Vicia faba were studied. The results indicated that the growth of the root length and mitotic index of root tip cells were successively decreased and even stopped with the increase of TCB concentrations and treatment duration. Numerical and structural chromosomal aberrations at metaphase and anaphase of root-tip cells in Vicia faba seedlings were produced by 50-300 micrograms.g-1 TCB treatment for 12-96 h. The percentage of c-mitosis, chromosomal bridge and chromosomal asymmetry array in root tip cells exposed to 50-100 micrograms.g-1 TCB for 12-24 h was up to 1.0-10.3%. The percentage of chromosomal stickness (S), chromosomal stickiness + chromosomal breakage (S + B), chromosomal stickness + chromosomal ring (S + R), chromosomal stickiness + chromosomal asymmetry array (S + A) and chromosomal stickness + chromosomal bridge (S + Be) in root tip cells reached 47.9-88.9%, and 18.1-29.6% for different kinds of chromosomal breakage at 300 micrograms.g-1 TCB for 12-96 h. Thus, the chromosomal aberration of root tip cells in Vicia faba seedlings could be used as a sensitive biomarker of monitoring soil contaminated with TCB.

  1. 30 CFR 7.100 - Explosion tests.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Explosion tests. 7.100 Section 7.100 Mineral... Underground Coal Mines Where Permissible Electric Equipment is Required § 7.100 Explosion tests. (a) Test procedures. (1) Prepare to test the diesel power package as follows: (i) Perform a detailed check of parts...

  2. 30 CFR 7.100 - Explosion tests.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Explosion tests. 7.100 Section 7.100 Mineral... Underground Coal Mines Where Permissible Electric Equipment is Required § 7.100 Explosion tests. (a) Test procedures. (1) Prepare to test the diesel power package as follows: (i) Perform a detailed check of parts...

  3. 30 CFR 7.100 - Explosion tests.

    Code of Federal Regulations, 2010 CFR

    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 procedures. (1) Prepare to test the diesel power package as follows: (i) Perform a detailed check of parts...

  4. Projectile-generating explosive access tool

    DOEpatents

    Jakaboski, Juan-Carlos [Albuquerque, NM; Hughs, Chance G [Tijeras, NM; Todd, Steven N [Rio Rancho, NM

    2011-10-18

    An explosive device that can generate a projectile from the opposite side of a wall from the side where the explosive device is detonated. The projectile can be generated without breaching the wall of the structure or container. The device can optionally open an aperture in a solid wall of a structure or a container and form a high-kinetic-energy projectile from the portion of the wall removed to create the aperture.

  5. Nuclear technologies for explosives detection

    NASA Astrophysics Data System (ADS)

    Bell, Curtis J.

    1992-12-01

    This paper presents an exploration of several techniques for detection of Improvised Explosive Devices (IED) using interactions of specific nuclei with gammarays or fast neutrons. Techniques considered use these interactions to identify the device by measuring the densities and/or relative concentrations of the elemental constituents of explosives. These techniques are to be compared with selected other nuclear and non-nuclear methods. Combining of nuclear and non-nuclear techniques will also be briefly discussed.

  6. Mesoscale Modeling of Deflagration-Induced Deconsolidation in Polymer-Bonded Explosives

    NASA Astrophysics Data System (ADS)

    Springer, H. Keo; Reaugh, J. E.; Glascoe, E. A.; Kercher, J. R.; Friedman, G.

    2011-06-01

    Initially intact 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 deflagration-induced damage on the transition to convective burning is not well understood. The objective of this study is to investigate the role of explosive constituent properties, microstructure, and deflagration velocity on deconsolidation. We performed simulations using the multi-physics hydrocode, ALE3D. HMX was used as the model energetic grain. We used a JWL form for the unreacted and reacted equation-of-state of the HMX. Simplified strength and failure models were used for the HMX and the binder. The propensity for deconsolidation increased with increasing grain volume fraction, increasing porosity, decreasing binder strength, and increasing deflagration velocity. These studies are important because they enable the development of deflagration-induced damage models, as well as the design of inherently safer explosives. This work performed under the auspices of the U.S. DOE by LLNL under Contract DE-AC52-07NA27344. This work was funded by the Joint DoD/DOE Munitions Technology Development Program.

  7. Toward an Empirically-Based Parametric Explosion Spectral Model

    DTIC Science & Technology

    2011-09-01

    Site (NNSS, formerly the Nevada Test Site ) with data from explosions at the Semipalatinsk Test ...Nevada Test Site ) with data from explosions at the Semipalatinsk Test Site recorded at the Borovoye Geophysical Observatory (BRV). The BRV data archive...explosions at Semipalatinsk Test Site of the former Soviet Union (Figure 4). As an example, we plot the regional phase spectra of one of

  8. Gas Retention in a Heated Plastic Bonded Explosive (LX-14).

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hobbs, Michael L.; Kaneshige, Michael J.; Erikson, William W.

    In prior work, we found that the nitroplasticizer in the plastic bonded explosive PBX 9501 played a crucial role in cookoff, especially when predicting response in larger systems [1]. We have recently completed experiments with a similar explosive, LX-14, that has a relatively nonreactive binder. We expected the ignition times for LX-14 to be longer than PBX 9501 since PBX 9501 has a more reactive binder. However, our experiments show the opposite trend. This paradox can be explained by retention of reactive gases within the interior of LX-14 by the higher strength binder resulting in faster ignition times. In contrast,more » the binder in PBX 9501 melts at low temperatures and does not retain decomposition gases as well as the LX-14 binder. Retention of reactive gases in LX-14 may also explain the more violent response in oblique impact tests [2] when compared to PBX 9501.« less

  9. Cosmological explosions from cold dark matter perturbations

    NASA Technical Reports Server (NTRS)

    Scherrer, Robert J.

    1992-01-01

    The cosmological-explosion model is examined for a universe dominated by cold dark matter in which explosion seeds are produced from the growth of initial density perturbations of a given form. Fragmentation of the exploding shells is dominated by the dark-matter potential wells rather than the self-gravity of the shells, and particular conditions are required for the explosions to bootstrap up to very large scales. The final distribution of dark matter is strongly correlated with the baryons on small scales, but uncorrelated on large scales.

  10. Statistical Hotspot Model for Explosive Detonation

    NASA Astrophysics Data System (ADS)

    Nichols, Albert

    2005-07-01

    The presence and need for energy localization in the ignition and detonation of high explosives is a corner stone in our understanding of explosive behavior. This energy localization, known as hot spots, provides the match that starts the energetic response that is integral to the detonation. In our model, we use the life cycle of a hot spot to predict explosive response. This life cycle begins with a random distribution of inhomogeneities in the explosive that we describe as a potential hot spot. A shock wave can transform these into hot spots that can then grow by consuming the explosive around them. The fact that the shock wave can collapse a potential hot spot without causing ignition is required in order to model phenomena like dead pressing. The burn rate of the hot spot is taken directly from experimental data. In our approach we do not assume that every hot spot is burning in an identical environment, but rather we take a statistical approach to the burning process. We also do not make a uniform temperature assumption in order to close the mixture equation of state, but track the flow of energy from reactant to product. Finally, we include both the hot spot burn model and a thermal decomposition path, required to explain certain long time behaviors. Building on work performed by Reaugh et. al., we have developed a set of reaction parameters for an HMX based heterogeneous explosive. These parameters have been determined from computer models on the micron scale, and experimental data. This model will be compared to experimental rate stick data. This work was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.

  11. Constraining the Energetics of Explosive Lava-Water Interactions

    NASA Astrophysics Data System (ADS)

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

    2017-12-01

    During volcanic eruptions, water, such as groundwater or melted ice or snow, may interact with magma within the conduit during eruption, generating explosions when the heat of the magma causes the water to rapidly turn to steam and expand, resulting in what we call a "phreatomagmatic" eruption. In 2010, the eruption of Eyjafjallajökull volcano in Iceland produced a plume of fine ash, through the interaction between magma and glacial melt water, which resulted in the closure of substantial airspace, ultimately costing a total of almost 5 billion dollars. Although an important area of study, it is difficult to quantify the effect of eternal water on eruption intensity when the gas inside of magma is also expanding and fragmenting the magma. In an attempt to understand the energetics of magma-water interactions, small-scale laboratory experiments have been performed. Explosion energy is found to depend mostly on kinetic energy, which is proportional to dispersal distance, and fragmentation energy, which is proportional to the mean grain size of the ejecta, and the mass percent of ash-sized grains. It is thought that in order to generate heat transfer rates sufficiently rapid to cause explosive detonation, the source melt must be finely fragmented, producing ash-sized grains. Those grains undergo brittle fragmentation due to rapid cooling and weak shock waves generated by the vaporization of superheated water. We take the novel approach of studying explosive interactions between lava and water to obtain additional explosion energy constraints. We identified and analyzed numerous beds of lava-water explosion ejecta of varying explosion energy, and we analyzed the ash-sized grains of these beds in detail. We verified that the mass of ash-sized grains increases with increasing explosion energy, and can form at the interface between lava and water. We found that brittle fragmentation occurs to a greater degree as grain size decreases and that the ash of highly

  12. Recent Advances in the Synthesis of High Explosive Materials

    DTIC Science & Technology

    2015-12-29

    explosives and secondary high explosives, and the sensitivities and properties of these molecules are provided. In addition to the synthesis of such materials...This review discusses the recent advances in the syntheses of high explosive energetic materials. Syntheses of some relevant modern primary

  13. Supersensitive fingerprinting of explosives by chemically modified nanosensors arrays.

    PubMed

    Lichtenstein, Amir; Havivi, Ehud; Shacham, Ronen; Hahamy, Ehud; Leibovich, Ronit; Pevzner, Alexander; Krivitsky, Vadim; Davivi, Guy; Presman, Igor; Elnathan, Roey; Engel, Yoni; Flaxer, Eli; Patolsky, Fernando

    2014-06-24

    The capability to detect traces of explosives sensitively, selectively and rapidly could be of great benefit for applications relating to civilian national security and military needs. Here, we show that, when chemically modified in a multiplexed mode, nanoelectrical devices arrays enable the supersensitive discriminative detection of explosive species. The fingerprinting of explosives is achieved by pattern recognizing the inherent kinetics, and thermodynamics, of interaction between the chemically modified nanosensors array and the molecular analytes under test. This platform allows for the rapid detection of explosives, from air collected samples, down to the parts-per-quadrillion concentration range, and represents the first nanotechnology-inspired demonstration on the selective supersensitive detection of explosives, including the nitro- and peroxide-derivatives, on a single electronic platform. Furthermore, the ultrahigh sensitivity displayed by our platform may allow the remote detection of various explosives, a task unachieved by existing detection technologies.

  14. Supersensitive fingerprinting of explosives by chemically modified nanosensors arrays

    NASA Astrophysics Data System (ADS)

    Lichtenstein, Amir; Havivi, Ehud; Shacham, Ronen; Hahamy, Ehud; Leibovich, Ronit; Pevzner, Alexander; Krivitsky, Vadim; Davivi, Guy; Presman, Igor; Elnathan, Roey; Engel, Yoni; Flaxer, Eli; Patolsky, Fernando

    2014-06-01

    The capability to detect traces of explosives sensitively, selectively and rapidly could be of great benefit for applications relating to civilian national security and military needs. Here, we show that, when chemically modified in a multiplexed mode, nanoelectrical devices arrays enable the supersensitive discriminative detection of explosive species. The fingerprinting of explosives is achieved by pattern recognizing the inherent kinetics, and thermodynamics, of interaction between the chemically modified nanosensors array and the molecular analytes under test. This platform allows for the rapid detection of explosives, from air collected samples, down to the parts-per-quadrillion concentration range, and represents the first nanotechnology-inspired demonstration on the selective supersensitive detection of explosives, including the nitro- and peroxide-derivatives, on a single electronic platform. Furthermore, the ultrahigh sensitivity displayed by our platform may allow the remote detection of various explosives, a task unachieved by existing detection technologies.

  15. The point explosion with radiation transport

    NASA Astrophysics Data System (ADS)

    Lin, Zhiwei; Zhang, Lu; Kuang, Longyu; Jiang, Shaoen

    2017-10-01

    Some amount of energy is released instantaneously at the origin to generate simultaneously a spherical radiative heat wave and a spherical shock wave in the point explosion with radiation transport, which is a complicated problem due to the competition between these two waves. The point explosion problem possesses self-similar solutions when only hydrodynamic motion or only heat conduction is considered, which are Sedov solution and Barenblatt solution respectively. The point explosion problem wherein both physical mechanisms of hydrodynamic motion and heat conduction are included has been studied by P. Reinicke and A.I. Shestakov. In this talk we numerically investigate the point explosion problem wherein both physical mechanisms of hydrodynamic motion and radiation transport are taken into account. The radiation transport equation in one dimensional spherical geometry has to be solved for this problem since the ambient medium is optically thin with respect to the initially extremely high temperature at the origin. The numerical results reveal a high compression of medium and a bi-peak structure of density, which are further theoretically analyzed at the end.

  16. Numerical Simulation of Energy Conversion Mechanism in Electric Explosion

    NASA Astrophysics Data System (ADS)

    Wanjun, Wang; Junjun, Lv; Mingshui, Zhu; Qiubo, Fu; EFIs Integration R&D Group Team

    2017-06-01

    Electric explosion happens when micron-scale metal films such as copper film is stimulated by short-time current pulse, while generating high temperature and high pressure plasma. The expansion process of the plasma plays an important role in the study of the generation of shock waves and the study of the EOS of matter under high pressure. In this paper, the electric explosion process is divided into two stages: the energy deposition stage and the quasi-isentropic expansion stage, and a dynamic EOS of plasma considering the energy replenishment is established. On this basis, flyer driven by plasma is studied numerically, the pressure and the internal energy of plasma in the energy deposition stage and the quasi - isentropic expansion stage are obtained by comparing the velocity history of the flyer with the experimental results. An energy conversion model is established, and the energy conversion efficiency of each process is obtained, and the influence of impedance matching relationship between flyer and metal plasma on the energy conversion efficiency is proposed in this paper.

  17. Accuracy of transcutaneous bilirubin measured by the BiliCare device in late preterm and term neonates.

    PubMed

    Kitsommart, Ratchada; Yangthara, Buranee; Wutthigate, Punnanee; Paes, Bosco

    2016-11-01

    The objective of this study is to explore the accuracy and performance of a new transcutaneous bilirubinometer (TCB) for the screening of jaundice in late preterm and term infants. A cross-sectional study was conducted. TCB measurements were performed using the BiliCare(TM) bilirubinometer. Paired TCB and serum bilirubin (SB) measurements were analysed. One hundred and fourteen paired samples were collected from 93 healthy late preterm and term infants. Bilirubin measurements were done at median (interquartile range) of 50.5 (34, 72) hours. The mean (SD) difference between the TCB and SB was 1.87 (1.98) mg/dL. A TCB cut-off level at 8.0 mg/dL provides a sensitivity of 97.3% with a negative predictive value (NPV) of 87.5% to detect a SB level of at least 8.0 mg/dL. For SB levels of at least 10.0 mg/dL, a TCB cut-off at 9.0 mg/dL shows a sensitivity of 97.5%; NPV 95.4%. For a SB level of at least 13.0 mg/dL, a TCB cut-off at 12 or 13 mg/dL had a sensitivity of 92.9% and NPV of 98.7%. The BiliCare(TM) demonstrated good performance with positive bias for the screening of jaundice in healthy late preterm or term infants. However, if adopted, proper cut-off levels should be chosen because of sub-optimal device precision.

  18. Underwater sympathetic detonation of pellet explosive

    NASA Astrophysics Data System (ADS)

    Kubota, Shiro; Saburi, Tei; Nagayama, Kunihito

    2017-06-01

    The underwater sympathetic detonation of pellet explosives was taken by high-speed photography. The diameter and the thickness of the pellet were 20 and 10 mm, respectively. The experimental system consists of the precise electric detonator, two grams of composition C4 booster and three pellets, and these were set in water tank. High-speed video camera, HPV-X made by Shimadzu was used with 10 Mfs. The underwater explosions of the precise electric detonator, the C4 booster and a pellet were also taken by high-speed photography to estimate the propagation processes of the underwater shock waves. Numerical simulation of the underwater sympathetic detonation of the pellet explosives was also carried out and compared with experiment.

  19. Characterization of Detonation Products of RSI-007 Explosive

    NASA Astrophysics Data System (ADS)

    Ager, Timothy; Neel, Christopher; Chhabildas, Lalit

    2011-06-01

    PDV and VISAR have been employed to characterize the detonation products of a production quality RSI-007 explosive. The explosive was part of an exploding foil initiator (EFI) detonator assembly in which the explosive was contained within a Kovar (Fe-Ni-Co alloy) cup. The free surface of the Kovar serves as the witness plate for the interferometry measurements. Detailed shock reverberations are recorded on the witness plate and the isentropic release path of the explosive is inferred though the velocity history. Two separate window materials are bonded to the Kovar cup in subsequent experiments and are used to further determine the release state in different pressure regimes. Presenter

  20. Characterization of detonation products of RSI-007 explosive

    NASA Astrophysics Data System (ADS)

    Ager, Timothy; Neel, Christopher; Breaux, Bradley; Vineski, Christopher; Welle, Eric; Lambert, David; Chhabildas, Lalit

    2012-03-01

    PDV and VISAR have been employed to characterize the detonation products of a high-purity CL-20 based explosive. The explosive was part of an exploding foil initiator (EFI) detonator assembly in which the explosive was contained within a Kovar (Fe-Ni-Co alloy) cup. The back surface of the Kovar serves as the witness plate for interferometry measurements. Detailed reverberations corresponding to shock arrival and release are recorded on the witness plate and the isentropic release path of the explosive is inferred though the velocity history. Two separate window materials are bonded to the Kovar cup in subsequent experiments and are used to further refine the release states.

  1. Explosive vapor detection payload for small robots

    NASA Astrophysics Data System (ADS)

    Stimac, Phil J.; Pettit, Michael; Wetzel, John P.; Haas, John W.

    2013-05-01

    Detection of explosive hazards is a critical component of enabling and improving operational mobility and protection of US Forces. The Autonomous Mine Detection System (AMDS) developed by the US Army RDECOM CERDEC Night Vision and Electronic Sensors Directorate (NVESD) is addressing this challenge for dismounted soldiers. Under the AMDS program, ARA has developed a vapor sampling system that enhances the detection of explosive residues using commercial-off-the-shelf (COTS) sensors. The Explosives Hazard Trace Detection (EHTD) payload is designed for plug-and-play installation and operation on small robotic platforms, addressing critical Army needs for more safely detecting concealed or exposed explosives in areas such as culverts, walls and vehicles. In this paper, we describe the development, robotic integration and performance of the explosive vapor sampling system, which consists of a sampling "head," a vapor transport tube and an extendable "boom." The sampling head and transport tube are integrated with the boom, allowing samples to be collected from targeted surfaces up to 7-ft away from the robotic platform. During sample collection, an IR lamp in the sampling head is used to heat a suspected object/surface and the vapors are drawn through the heated vapor transport tube to an ion mobility spectrometer (IMS) for detection. The EHTD payload is capable of quickly (less than 30 seconds) detecting explosives such as TNT, PETN, and RDX at nanogram levels on common surfaces (brick, concrete, wood, glass, etc.).

  2. Explosion-Induced Implosions of Cylindrical Shell Structures

    NASA Astrophysics Data System (ADS)

    Ikeda, C. M.; Duncan, J. H.

    2010-11-01

    An experimental study of the explosion-induced implosion of cylindrical shell structures in a high-pressure water environment was performed. The shell structures are filled with air at atmospheric pressure and are placed in a large water-filled pressure vessel. The vessel is then pressurized to various levels P∞=αPc, where Pc is the natural implosion pressure of the model and α is a factor that ranges from 0.1 to 0.9. An explosive is then set off at various standoff distances, d, from the model center line, where d varies from R to 10R and R is the maximum radius of the explosion bubble. High-speed photography (27,000 fps) was used to observe the explosion and resulting shell structure implosion. High-frequency underwater blast sensors recorded dynamic pressure waves at 6 positions. The cylindrical models were made from aluminum (diameter D = 39.1 mm, wall thickness t = 0.89 mm, length L = 240 mm) and brass (D = 16.7 mm, t = 0.36 mm, L=152 mm) tubes. The pressure records are interpreted in light of the high-speed movies. It is found that the implosion is induced by two mechanisms: the shockwave generated by the explosion and the jet formed during the explosion-bubble collapse. Whether an implosion is caused by the shockwave or the jet depends on the maximum bubble diameter and the standoff distance.

  3. Explosive-residue compounds resulting from snow avalanche control in the Wasatch Mountains of Utah

    USGS Publications Warehouse

    Naftz, David L.; Kanagy, Leslie K.; Susong, David D.; Wydoski, Duane S.; Kanagy, Christopher J.

    2003-01-01

    A snow avalanche is a powerful force of nature that can play a significant role in developing mountain landscapes (Perla and Martinelli, 1975). More importantly, loss of life can occur when people are caught in the path of snow avalanches (Grossman, 1999). Increasing winter recreation, including skiing, snowboarding, snowmobiling, snowshoeing, and climbing in mountainous areas, has increased the likelihood of people encountering snow avalanches (fig. 1). Explosives are used by most ski areas and State highway departments throughout the Western United States to control the release of snow avalanches, thus minimizing the loss of human life during winter recreation and highway travel (fig. 2).Common explosives used for snow avalanche control include trinitrotoluene (TNT), pentaerythritoltetranitrate (PETN), cyclotrimethylenetrinitramine (RDX), tetrytol, ammonium nitrate, and nitroglycerin (Perla and Martinelli, 1975). During and after snowfall or wind loading of potential avalanche slopes, ski patrollers and Utah Department of Transportation personnel deliver explosive charges onto predetermined targets to artificially release snow avalanches, thereby rendering the slope safer for winter activities. Explosives can be thrown by hand onto target zones or shot from cannons for more remote delivery of explosive charges. Hand-delivered charges typically contain about 2 pounds of TNT or its equivalent (Perla and Martinelli, 1975).Depending on the size of the ski area, acreage of potential avalanche terrain, and weather conditions, the annual quantity of explosives used during a season of snow avalanche control can be substantial. For example, the three ski areas of Alta, Snowbird, and Brighton, plus the Utah Department of Transportation, may use as many as 11,200 hand charges per year (Wasatch Powderbird Guides, unpub. data, 1999) for snow avalanche control in Big and Little Cottonwood Canyons (fig. 3). If each charge is assumed to weigh 2 pounds, this equates to about 22

  4. Explosive complexes

    DOEpatents

    Huynh, My Hang V [Los Alamos, NM

    2009-09-22

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

  5. Explosive complexes

    DOEpatents

    Huynh, My Hang V [Los Alamos, NM

    2011-08-16

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

  6. Optimum performance of explosives in a quasistatic detonation cycle

    NASA Astrophysics Data System (ADS)

    Baker, Ernest L.; Stiel, Leonard I.

    2017-01-01

    Analyses were conducted on the behavior of explosives in a quasistatic detonation cycle. This type of cycle has been proposed for the determination of the maximum work that can be performed by the explosive. The Jaguar thermochemical equilibrium program enabled the direct analyses of explosive performance at the various steps in the detonation cycle. In all cases the explosive is initially detonated to a point on the Hugoniot curve for the reaction products. The maximum useful work that can be obtained from the explosive is equal to the P-V work on the isentrope for expansion after detonation to atmospheric pressure, minus one-half the square of the particle velocity at the detonation point. This quantity is calculated form the internal energy of the explosive at the initial and final atmospheric temperatures. Cycle efficiencies (net work/ heat added) are also calculated with these procedures. For several explosives including TNT, RDX, and aluminized compositions, maximum work effects were established through the Jaguar calculations for Hugoniot points corresponding to C-J, overdriven, underdriven and constant volume detonations. Detonation to the C-J point is found to result in the maximum net work in all cases.

  7. Direct real-time detection of vapors from explosive compounds.

    PubMed

    Ewing, Robert G; Clowers, Brian H; Atkinson, David A

    2013-11-19

    The real-time detection of vapors from low volatility explosives including PETN, tetryl, RDX, and nitroglycerine along with various compositions containing these substances was demonstrated. This was accomplished with an atmospheric flow tube (AFT) using a nonradioactive ionization source coupled to a mass spectrometer. Direct vapor detection was accomplished in less than 5 s at ambient temperature without sample preconcentration. The several seconds of residence time of analytes in the AFT provided a significant opportunity for reactant ions to interact with analyte vapors to achieve ionization. This extended reaction time, combined with the selective ionization using the nitrate reactant ions (NO3(-) and NO3(-)·HNO3), enabled highly sensitive explosives detection from explosive vapors present in ambient laboratory air. Observed signals from diluted explosive vapors indicated detection limits below 10 ppqv using selected ion monitoring (SIM) of the explosive-nitrate adduct at m/z 349, 378, 284, and 289 for tetryl, PETN, RDX, and NG, respectively. Also provided is a demonstration of the vapor detection from 10 different energetic formulations sampled in ambient laboratory air, including double base propellants, plastic explosives, and commercial blasting explosives using SIM for the NG, PETN, and RDX product ions.

  8. Optical measurements of flyer plate acceleration by emulsion explosive

    NASA Astrophysics Data System (ADS)

    Kubota, Shiro; Shimada, Hideki; Matsui, Kikuo; Ogata, Yuji; Seto, Masahiro; Masui, Akira; Wada, Yuji; Liu, Zhi-Yue; Itoh, Shigeru

    2001-04-01

    This paper presents the study on the application of explosive welding technique to the field of the urgent repair of the gas and water pipe networks. The essential parameters related to the explosive welding are scrutinized from the point of view of the minimizing the damage to the steel pipe after welded explosively with a flyer plate. The emulsion explosive is contained in a rectangular hard-paper box whose bottom is the flyer plate with 100 mm length, 25 mm width and 1.5 mm thickness. The flyer motions of the flyer plates accelerated by emulsion explosive are observed by high-speed photography from the side and front view of the flyer plate. The damage to the pipe by the flyer plate is discussed with the results of the observation of flyer motion and explosive welding test under various experimental conditions. Moreover, one way to control the motion of the flyer plate is proposed. We put a PMMA buffer block into the explosive. The flying process of flyer plate is calculated by the finite different scheme based on the ALE method. The effectiveness of this method is demonstrated by the experimental and numerical studies.

  9. Eigenvalue Detonation of Combined Effects Aluminized Explosives

    NASA Astrophysics Data System (ADS)

    Capellos, C.; Baker, E. L.; Nicolich, S.; Balas, W.; Pincay, J.; Stiel, L. I.

    2007-12-01

    Theory and performance for recently developed combined—effects aluminized explosives are presented. Our recently developed combined-effects aluminized explosives (PAX-29C, PAX-30, PAX-42) are capable of achieving excellent metal pushing, as well as high blast energies. Metal pushing capability refers to the early volume expansion work produced during the first few volume expansions associated with cylinder and wall velocities and Gurney energies. Eigenvalue detonation explains the observed detonation states achieved by these combined effects explosives. Cylinder expansion data and thermochemical calculations (JAGUAR and CHEETAH) verify the eigenvalue detonation behavior.

  10. The physics, chemistry and dynamics of explosions.

    PubMed

    Oran, Elaine S; Williams, Forman A

    2012-02-13

    The motivation for devoting a Theme Issue to explosions is discussed. As subsequent articles in the issue are written with the assumption that the reader has had a certain amount of previous exposure to the subject, some of the history and necessary background information are presented here. The topics on explosions that will be encountered in the remaining articles are previewed. Finally, several important future outstanding research problems, beyond those addressed in the following articles, are discussed, with the objective of complementing the coverage of explosions in this issue.

  11. Intermittent Explosive Disorder

    MedlinePlus

    ... explosive disorder have an increased risk of: Impaired interpersonal relationships. They're often perceived by others as ... logo are trademarks of Mayo Foundation for Medical Education and Research. © 1998-2018 Mayo Foundation for Medical ...

  12. 49 CFR 173.160 - Bombs, smoke, non-explosive (corrosive).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Bombs, smoke, non-explosive (corrosive). 173.160 Section 173.160 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS... Class 1 and Class 7 § 173.160 Bombs, smoke, non-explosive (corrosive). Bombs, smoke, non-explosive may...

  13. 49 CFR 173.160 - Bombs, smoke, non-explosive (corrosive).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Bombs, smoke, non-explosive (corrosive). 173.160 Section 173.160 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS... Class 1 and Class 7 § 173.160 Bombs, smoke, non-explosive (corrosive). Bombs, smoke, non-explosive may...

  14. 49 CFR 173.160 - Bombs, smoke, non-explosive (corrosive).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Bombs, smoke, non-explosive (corrosive). 173.160 Section 173.160 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS... Class 1 and Class 7 § 173.160 Bombs, smoke, non-explosive (corrosive). Bombs, smoke, non-explosive may...

  15. 49 CFR 173.160 - Bombs, smoke, non-explosive (corrosive).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Bombs, smoke, non-explosive (corrosive). 173.160 Section 173.160 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS... Class 1 and Class 7 § 173.160 Bombs, smoke, non-explosive (corrosive). Bombs, smoke, non-explosive may...

  16. 49 CFR 173.160 - Bombs, smoke, non-explosive (corrosive).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Bombs, smoke, non-explosive (corrosive). 173.160 Section 173.160 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS... Class 1 and Class 7 § 173.160 Bombs, smoke, non-explosive (corrosive). Bombs, smoke, non-explosive may...

  17. The Soviet Program for Peaceful Uses of Nuclear Explosions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nordyke, M.D.

    2000-07-26

    During a period of some 23 years between 1965 and 1988, the Soviet Union's ''Program for the Utilization of Nuclear Explosions in the National Economy'' carried out 122 nuclear explosions to study and put into industrial use some 13 applications. In all, 128 explosives with yields ranging from 0.01 to 140 kt were used, with the vast majority being between 2 and 20 kt. Most peaceful applications of nuclear explosions in the Soviet PNE Program were explored in depth with a number of tests, but unfortunately little has been reported on the technical results other than general outcomes. Two applications,more » deep seismic sounding of the Earth's crust and upper mantle and the creation of underground cavities in salt for the storage of gas condensate, found widespread use, representing over 50% of all the explosions. Explosions to explore the technical possibilities of stimulating the production of oil and gas reservoirs accounted for an additional 17%.« less

  18. Potential Explosion Hazard of Carbonaceous Nanoparticles: Screening of Allotropes

    PubMed Central

    Turkevich, Leonid A.; Fernback, Joseph; Dastidar, Ashok G.; Osterberg, Paul

    2016-01-01

    There is a concern that engineered carbon nanoparticles, when manufactured on an industrial scale, will pose an explosion hazard. Explosion testing has been performed on 20 codes of carbonaceous powders. These include several different codes of SWCNTs (single-walled carbon nanotubes), MWCNTs (multi-walled carbon nanotubes) and CNFs (carbon nanofibers), graphene, diamond, fullerene, as well as several different control carbon blacks and graphites. Explosion screening was performed in a 20 L explosion chamber (ASTM E1226 protocol), at a concentration of 500 g/m3, using a 5 kJ ignition source. Time traces of overpressure were recorded. Samples typically exhibited overpressures of 5–7 bar, and deflagration index KSt = V1/3 (dP/dt)max ~ 10 – 80 bar-m/s, which places these materials in European Dust Explosion Class St-1. There is minimal variation between these different materials. The explosive characteristics of these carbonaceous powders are uncorrelated with primary particle size (BET specific surface area). PMID:27468178

  19. SWAN - Detection of explosives by means of fast neutron activation analysis

    NASA Astrophysics Data System (ADS)

    Gierlik, M.; Borsuk, S.; Guzik, Z.; Iwanowska, J.; Kaźmierczak, Ł.; Korolczuk, S.; Kozłowski, T.; Krakowski, T.; Marcinkowski, R.; Swiderski, L.; Szeptycka, M.; Szewiński, J.; Urban, A.

    2016-10-01

    In this work we report on SWAN, the experimental, portable device for explosives detection. The device was created as part of the EU Structural Funds Project "Accelerators & Detectors" (POIG.01.01.02-14-012/08-00), with the goal to increase beneficiary's expertise and competencies in the field of neutron activation analysis. Previous experiences and budged limitations lead toward a less advanced design based on fast neutron interactions and unsophisticated data analysis with the emphasis on the latest gamma detection and spectrometry solutions. The final device has been designed as a portable, fast neutron activation analyzer, with the software optimized for detection of carbon, nitrogen and oxygen. SWAN's performance in the role of explosives detector is elaborated in this paper. We demonstrate that the unique features offered by neutron activation analysis might not be impressive enough when confronted with practical demands and expectations of a generic homeland security customer.

  20. Shallow magma diversions during explosive diatreme-forming eruptions.

    PubMed

    Le Corvec, Nicolas; Muirhead, James D; White, James D L

    2018-04-13

    The diversion of magma is an important mechanism that may lead to the relocation of a volcanic vent. Magma diversion is known to occur during explosive volcanic eruptions generating subterranean excavation and remobilization of country and volcanic rocks. However, feedbacks between explosive crater formation and intrusion processes have not been considered previously, despite their importance for understanding evolving hazards during volcanic eruptions. Here, we apply numerical modeling to test the impacts of excavation and subsequent infilling of diatreme structures on stress states and intrusion geometries during the formation of maar-diatreme complexes. Explosive excavation and infilling of diatremes affects local stress states which inhibits magma ascent and drives lateral diversion at various depths, which are expected to promote intra-diatreme explosions, host rock mixing, and vent migration. Our models demonstrate novel mechanisms explaining the generation of saucer-shaped sills, linked with magma diversion and enhanced intra-diatreme explosive fragmentation during maar-diatreme volcanism. Similar mechanisms will occur at other volcanic vents producing crater-forming eruptions.

  1. Controlled Detonation Dynamics in Additively Manufactured High Explosives

    NASA Astrophysics Data System (ADS)

    Schmalzer, Andrew; Tappan, Bryce; Bowden, Patrick; Manner, Virginia; Clements, Brad; Menikoff, Ralph; Ionita, Axinte; Branch, Brittany; Dattelbaum, Dana; Espy, Michelle; Patterson, Brian; Wu, Ruilian; Mueller, Alexander

    2017-06-01

    The effect of structure in explosives has long been a subject of interest to explosives engineers and scientists. Through structure, detonation dynamics in explosives can be manipulated, introducing a new level of safety and directed performance into these previously difficult to control materials. New advances in additive manufacturing (AM) allow the deliberate introduction of exact internal structures at dimensions approaching the mesoscale of these energetic materials. We show through simulation and experiment that this structure can be used to control detonation behavior by manipulating complex shockwave interactions. We use high-speed video and shorting mag-wires to determine the detonation velocity in AM generated explosive structures, demonstrating, for the first time, a method of controlling the directional propagation of reactive flow through the controlled introduction of structure within a high explosive. With ongoing improvement in the AM methods available coupled with guidance through modeling and simulations, more complex interactions are being explored. LANL LDRD Office.

  2. Phreatic and Hydrothermal Explosions: A Laboratory Approach

    NASA Astrophysics Data System (ADS)

    Scheu, B.; Dingwell, D. B.

    2010-12-01

    Phreatic eruptions are amongst the most common eruption types on earth. They might be precursory to another type of volcanic eruption but often they stand on their one. Despite being the most common eruption type, they also are one of the most diverse eruptions, in appearance as well as on eruption mechanism. Yet steam is the common fuel behind all phreatic eruptions. The steam-driven explosions occur when water beneath the ground or on the surface is heated by magma, lava, hot rocks, or fresh volcanic deposits (such as ignimbrites, tephra and pyroclastic-flow deposits) and result in crater, tuff rings and debris avalanches. The intense heat of such material may cause water to boil and flash to steam, thereby generating an explosion of steam, water, ash, blocks, and bombs. Another wide and important field affected by phreatic explosions are hydrothermal areas; here phreatic explosions occur every few months creating explosion craters and resemble a significant hazard to hydrothermal power plants. Despite of their hazard potential, phreatic explosions have so far been overlooked by the field of experimental volcanology. A part of their hazard potential in owned by the fact that phreatic explosions are hardly predictable in occurrence time and size as they have manifold triggers (variances in groundwater and heat systems, earthquakes, material fatigue, water level, etc..) A new set of experiments has been designed to focus on this phreatic type of steam explosion, whereas classical phreatomagmatic experiments use molten fuel-coolant interaction (e.g., Zimanowski, et al., 1991). The violent transition of the superheated water to vapour adds another degree of explosivity to the dry magmatic fragmentation, driven mostly by vesicle bursting due to internal gas overpressure. At low water fractions the fragmentation is strongly enforced by the mixture of these two effects and a large fraction of fine pyroclasts are produced, whereas at high water fraction in the sample the

  3. Explosives signatures and analysis

    NASA Astrophysics Data System (ADS)

    Fountain, Augustus Way, III; Oyler, Jonathan M.; Ostazeski, Stanley A.

    2008-04-01

    The challenge of sampling explosive materials for various high threat military and civilian operational scenarios requires the community to identify and exploit other chemical compounds within the mixtures that may be available to support stand-off detection techniques. While limited surface and vapor phase characterization of IEDs exist, they are insufficient to guide the future development and evaluation of field deployable explosives detection (proximity and standoff) capabilities. ECBC has conducted a limited investigation of three artillery ammunition types to determine what chemical vapors, if any, are available for sensing; the relative composition of the vapors which includes the more volatile compounds in munitions, i.e., plastersizers and binders; and the sensitivity needed detect these vapors at stand-off. Also in partnership with MIT-Lincoln Laboratory, we performed a background measurement campaign at the National Training Center to determine the baseline ambient amounts and variability of nitrates and nitro-ester compounds as vapors, particulates, and on surfaces; as well as other chemical compounds related to non-energetic explosive additives. Environmental persistence studies in contexts relevant to counter-IED sensing operations, such as surface residues, are still necessary.

  4. Infrasound Studies for Yield Estimation of HE Explosions

    DTIC Science & Technology

    2011-03-05

    AFRL-RV-HA-TR-2011-1022 Infrasound Studies for Yield Estimation of HE Explosions Paul Golden Petru Negraru Southern Methodist...DATES COVERED (From - To) 5 Mar 2010 to 5 Mar 2011 4. TITLE AND SUBTITLE Infrasound Studies for Yield Estimation of HE Explosions 5a. CONTRACT NUMBER...conducting investigations to determine the yield of HE explosions from infrasound signals. In particular SMU is investigating how the period and amplitude

  5. Application of paper spray ionization for explosives analysis.

    PubMed

    Tsai, Chia-Wei; Tipple, Christopher A; Yost, Richard A

    2017-10-15

    A desired feature in the analysis of explosives is to decrease the time of the entire analysis procedure, including sampling. A recently utilized ambient ionization technique, paper spray ionization (PSI), provides the possibility of combining sampling and ionization. However, an interesting phenomenon that occurs in generating negatively charged ions pose some challenges in applying PSI to explosives analysis. The goal of this work is to investigate the possible solutions for generating explosives ions in negative mode PSI. The analysis of 2,4,6-trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) was performed. Several solvent systems with different surface tensions and additives were compared to determine their effect on the ionization of explosives. The solvents tested include tert-butanol, isopropanol, methanol, and acetonitrile. The additives tested were carbon tetrachloride and ammonium nitrate. Of the solvents tested, isopropanol yielded the best results. In addition, adding ammonium nitrate to the isopropanol enhanced the analyte signal. Experimentally determined limits of detection (LODs) as low as 0.06 ng for PETN, on paper, were observed with isopropanol and the addition of 0.4 mM ammonium nitrate as the spray solution. In addition, the explosive components of two plastic explosive samples, Composition 4 and Semtex, were successfully analyzed via surface sampling when using the developed method. The analysis of explosives using PSI-MS in negative ion mode was achieved. The addition of ammonium nitrate to isopropanol, in general, enhanced the analyte signal and yielded better ionization stability. Real-world explosive samples were analyzed, which demonstrates one of the potential applications of PSI-MS analysis. Copyright © 2017 John Wiley & Sons, Ltd.

  6. 31 CFR 0.215 - Possession of weapons and explosives.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance: Treasury 1 2012-07-01 2012-07-01 false Possession of weapons and explosives... OF THE TREASURY EMPLOYEE RULES OF CONDUCT Rules of Conduct § 0.215 Possession of weapons and explosives. (a) Employees shall not possess firearms, explosives, or other dangerous or deadly weapons...

  7. 31 CFR 0.215 - Possession of weapons and explosives.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance: Treasury 1 2014-07-01 2014-07-01 false Possession of weapons and explosives... OF THE TREASURY EMPLOYEE RULES OF CONDUCT Rules of Conduct § 0.215 Possession of weapons and explosives. (a) Employees shall not possess firearms, explosives, or other dangerous or deadly weapons...

  8. 31 CFR 0.215 - Possession of weapons and explosives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance: Treasury 1 2011-07-01 2011-07-01 false Possession of weapons and explosives... OF THE TREASURY EMPLOYEE RULES OF CONDUCT Rules of Conduct § 0.215 Possession of weapons and explosives. (a) Employees shall not possess firearms, explosives, or other dangerous or deadly weapons...

  9. 31 CFR 0.215 - Possession of weapons and explosives.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance: Treasury 1 2013-07-01 2013-07-01 false Possession of weapons and explosives... OF THE TREASURY EMPLOYEE RULES OF CONDUCT Rules of Conduct § 0.215 Possession of weapons and explosives. (a) Employees shall not possess firearms, explosives, or other dangerous or deadly weapons...

  10. 31 CFR 0.215 - Possession of weapons and explosives.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Possession of weapons and explosives... OF THE TREASURY EMPLOYEE RULES OF CONDUCT Rules of Conduct § 0.215 Possession of weapons and explosives. (a) Employees shall not possess firearms, explosives, or other dangerous or deadly weapons...

  11. 49 CFR 1544.213 - Use of explosives detection systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 9 2011-10-01 2011-10-01 false Use of explosives detection systems. 1544.213...: AIR CARRIERS AND COMMERCIAL OPERATORS Operations § 1544.213 Use of explosives detection systems. (a) Use of explosive detection equipment. If TSA so requires by an amendment to an aircraft operator's...

  12. 49 CFR 1544.213 - Use of explosives detection systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 9 2014-10-01 2014-10-01 false Use of explosives detection systems. 1544.213...: AIR CARRIERS AND COMMERCIAL OPERATORS Operations § 1544.213 Use of explosives detection systems. (a) Use of explosive detection equipment. If TSA so requires by an amendment to an aircraft operator's...

  13. 49 CFR 1544.213 - Use of explosives detection systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 9 2013-10-01 2013-10-01 false Use of explosives detection systems. 1544.213...: AIR CARRIERS AND COMMERCIAL OPERATORS Operations § 1544.213 Use of explosives detection systems. (a) Use of explosive detection equipment. If TSA so requires by an amendment to an aircraft operator's...

  14. 49 CFR 1544.213 - Use of explosives detection systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 9 2012-10-01 2012-10-01 false Use of explosives detection systems. 1544.213...: AIR CARRIERS AND COMMERCIAL OPERATORS Operations § 1544.213 Use of explosives detection systems. (a) Use of explosive detection equipment. If TSA so requires by an amendment to an aircraft operator's...

  15. Explosive origin of silicic lava: Textural and δD-H2O evidence for pyroclastic degassing during rhyolite effusion

    NASA Astrophysics Data System (ADS)

    Castro, Jonathan M.; Bindeman, Ilya N.; Tuffen, Hugh; Ian Schipper, C.

    2014-11-01

    A long-standing challenge in volcanology is to explain why explosive eruptions of silicic magma give way to lava. A widely cited idea is that the explosive-to-effusive transition manifests a two-stage degassing history whereby lava is the product of non-explosive, open-system gas release following initial explosive, closed-system degassing. Direct observations of rhyolite eruptions indicate that effusive rhyolites are in fact highly explosive, as they erupt simultaneously with violent volcanic blasts and pyroclastic fountains for months from a common vent. This explosive and effusive overlap suggests that pyroclastic processes play a key role in rendering silicic magma sufficiently degassed to generate lava. Here we use precise H-isotope and magmatic H2O measurements and textural evidence to demonstrate that effusion results from explosion(s)-lavas are the direct product of brittle deformation that fosters batched degassing into transient pyroclastic channels (tuffisites) that repetitively and explosively vent from effusing lava. Our measurements show, specifically that D/H ratios and H2O contents of a broad suite of explosive and effusive samples from Chaitén volcano (hydrous bombs, Plinian pyroclasts, tuffisite veins, and lava) define a single and continuous degassing trend that links wet explosive pyroclasts (∼ 1.6 wt.% H2O, δD = - 76.4 ‰) to dry obsidian lavas (∼ 0.13 wt.% H2O, δD = - 145.7 ‰). This geochemical pattern is best fit with batched degassing model that comprises small repeated closed-system degassing steps followed by pulses of vapour extraction. This degassing mechanism is made possible by the action of tuffisite veins, which, by tapping already vesicular or brecciated magma, allow batches of exsolved gas to rapidly and explosively escape from relatively isolated closed-system domains and large tracts of conduit magma by giving them long-range connectivity. Even though tuffisite veins render magma degassed and capable of effusing, they

  16. Optically-energized, emp-resistant, fast-acting, explosion initiating device

    DOEpatents

    Benson, David A.; Kuswa, Glenn W.

    1987-01-01

    Optical energy, provided from a remote user-operated source, is utilized to initially electrically charge a capacitor in a circuit that also contains an explosion initiating transducer in contact with a small explosive train contained in an attachable housing. Additional optical energy is subsequently supplied in a preferred embodiment to an optically responsive phototransistor acting in conjunction with a silicon controlled rectifer to release the stored electrical energy through the explosion initiating transducer to set off the explosive train. All energy transfers between the user and the explosive apparatus, either for charging it up or for setting it off, are conveyed optically and may be accomplished in a single optical fiber with coding to distinguish between specific optical energy transfers and between these and any extraneous signals.

  17. Green primary explosives: 5-Nitrotetrazolato-N2-ferrate hierarchies

    PubMed Central

    Huynh, My Hang V.; Coburn, Michael D.; Meyer, Thomas J.; Wetzler, Modi

    2006-01-01

    The sensitive explosives used in initiating devices like primers and detonators are called primary explosives. Successful detonations of secondary explosives are accomplished by suitable sources of initiation energy that is transmitted directly from the primaries or through secondary explosive boosters. Reliable initiating mechanisms are available in numerous forms of primers and detonators depending upon the nature of the secondary explosives. The technology of initiation devices used for military and civilian purposes continues to expand owing to variations in initiating method, chemical composition, quantity, sensitivity, explosive performance, and other necessary built-in mechanisms. Although the most widely used primaries contain toxic lead azide and lead styphnate, mixtures of thermally unstable primaries, like diazodinitrophenol and tetracene, or poisonous agents, like antimony sulfide and barium nitrate, are also used. Novel environmentally friendly primary explosives are expanded here to include cat[FeII(NT)3(H2O)3], cat2[FeII(NT)4(H2O)2], cat3[FeII(NT)5(H2O)], and cat4[FeII(NT)6] with cat = cation and NT− = 5-nitrotetrazolato-N2. With available alkaline, alkaline earth, and organic cations as partners, four series of 5-nitrotetrazolato-N2-ferrate hierarchies have been prepared that provide a plethora of green primaries with diverse initiating sensitivity and explosive performance. They hold great promise for replacing not only toxic lead primaries but also thermally unstable primaries and poisonous agents. Strategies are also described for the systematic preparation of coordination complex green primaries based on appropriate selection of ligands, metals, and synthetic procedures. These strategies allow for maximum versatility in initiating sensitivity and explosive performance while retaining properties required for green primaries. PMID:16803957

  18. Green primary explosives: 5-nitrotetrazolato-N2-ferrate hierarchies.

    PubMed

    Huynh, My Hang V; Coburn, Michael D; Meyer, Thomas J; Wetzler, Modi

    2006-07-05

    The sensitive explosives used in initiating devices like primers and detonators are called primary explosives. Successful detonations of secondary explosives are accomplished by suitable sources of initiation energy that is transmitted directly from the primaries or through secondary explosive boosters. Reliable initiating mechanisms are available in numerous forms of primers and detonators depending upon the nature of the secondary explosives. The technology of initiation devices used for military and civilian purposes continues to expand owing to variations in initiating method, chemical composition, quantity, sensitivity, explosive performance, and other necessary built-in mechanisms. Although the most widely used primaries contain toxic lead azide and lead styphnate, mixtures of thermally unstable primaries, like diazodinitrophenol and tetracene, or poisonous agents, like antimony sulfide and barium nitrate, are also used. Novel environmentally friendly primary explosives are expanded here to include cat[Fe(II)(NT)(3)(H(2)O)(3)], cat(2)[Fe(II)(NT)(4)(H(2)O)(2)], cat(3)[Fe(II)(NT)(5)(H(2)O)], and cat(4)[Fe(II)(NT)(6)] with cat = cation and NT(-) = 5-nitrotetrazolato-N(2). With available alkaline, alkaline earth, and organic cations as partners, four series of 5-nitrotetrazolato-N(2)-ferrate hierarchies have been prepared that provide a plethora of green primaries with diverse initiating sensitivity and explosive performance. They hold great promise for replacing not only toxic lead primaries but also thermally unstable primaries and poisonous agents. Strategies are also described for the systematic preparation of coordination complex green primaries based on appropriate selection of ligands, metals, and synthetic procedures. These strategies allow for maximum versatility in initiating sensitivity and explosive performance while retaining properties required for green primaries.

  19. Projectile-generating explosive access tool

    DOEpatents

    Jakaboski, Juan-Carlos; Hughs, Chance G; Todd, Steven N

    2013-06-11

    A method for generating a projectile using an explosive device that can generate a projectile from the opposite side of a wall from the side where the explosive device is detonated. The projectile can be generated without breaching the wall of the structure or container. The device can optionally open an aperture in a solid wall of a structure or a container and form a high-kinetic-energy projectile from the portion of the wall removed to create the aperture.

  20. Explosive destruction system for disposal of chemical munitions

    DOEpatents

    Tschritter, Kenneth L [Livermore, CA; Haroldsen, Brent L [Manteca, CA; Shepodd, Timothy J [Livermore, CA; Stofleth, Jerome H [Albuquerque, NM; DiBerardo, Raymond A [Baltimore, MD

    2005-04-19

    An explosive destruction system and method for safely destroying explosively configured chemical munitions. The system comprises a sealable, gas-tight explosive containment vessel, a fragment suppression system positioned in said vessel, and shaped charge means for accessing the interior of the munition when the munition is placed within the vessel and fragment suppression system. Also provided is a means for treatment and neutralization of the munition's chemical fills, and means for heating and agitating the contents of the vessel. The system is portable, rapidly deployable and provides the capability of explosively destroying and detoxifying chemical munitions within a gas-tight enclosure so that there is no venting of toxic or hazardous chemicals during detonation.

  1. Estimating Equivalency of Explosives Through A Thermochemical Approach

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maienschein, J L

    2002-07-08

    The Cheetah thermochemical computer code provides an accurate method for estimating the TNT equivalency of any explosive, evaluated either with respect to peak pressure or the quasi-static pressure at long time in a confined volume. Cheetah calculates the detonation energy and heat of combustion for virtually any explosive (pure or formulation). Comparing the detonation energy for an explosive with that of TNT allows estimation of the TNT equivalency with respect to peak pressure, while comparison of the heat of combustion allows estimation of TNT equivalency with respect to quasi-static pressure. We discuss the methodology, present results for many explosives, andmore » show comparisons with equivalency data from other sources.« less

  2. Numerical Simulation of the Detonation of Condensed Explosives

    NASA Astrophysics Data System (ADS)

    Wang, Cheng; Ye, Ting; Ning, Jianguo

    Detonation process of a condensed explosive was simulated using a finite difference method. Euler equations were applied to describe the detonation flow field, an ignition and growth model for the chemical reaction and Jones-Wilkins-Lee (JWL) equations of state for the state of explosives and detonation products. Based on the simple mixture rule that assumes the reacting explosives to be a mixture of the reactant and product components, 1D and 2D codes were developed to simulate the detonation process of high explosive PBX9404. The numerical results are in good agreement with the experimental results, which demonstrates that the finite difference method, mixture rule and chemical reaction proposed in this paper are adequate and feasible.

  3. Seismic and source characteristics of large chemical explosions. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Adushkin, V.V.; Kostuchenko, V.N.; Pernik, L.M.

    From the very beginning of its arrangement in 1947, the Institute for Dynamics of the Geospheres RAS (former Special Sector of the Institute for physics of the Earth, RAS) was providing scientific observations of effects of nuclear explosions, as well as large-scale detonations of HE, on environment. This report presents principal results of instrumental observations obtained from various large-scale chemical explosions conducted in the Former-Soviet Union in the period of time from 1957 to 1989. Considering principal aim of the work, tamped and equivalent chemical explosions have been selected with total weights from several hundreds to several thousands ton. Inmore » particular, the selected explosions were aimed to study scaling law from excavation explosions, seismic effect of tamped explosions, and for dam construction for hydropower stations and soil melioration. Instrumental data on surface explosions of total weight in the same range aimed to test military technics and special objects are not included.« less

  4. Detection of vehicle-based improvised explosives using ultra-trace detection equipment

    NASA Astrophysics Data System (ADS)

    Fisher, Mark; Sikes, John; Prather, Mark; Wichert, Clint

    2005-05-01

    Vehicle-borne improvised explosive devices (VBIEDs) have become the weapon of choice for insurgents in Iraq. At the same time, these devices are becoming increasingly sophisticated and effective. VBIEDs can be difficult to detect during visual inspection of vehicles. This is especially true when explosives have been hidden behind a vehicle"s panels, inside seat cushions, under floorboards, or behind cargo. Even though the explosive may not be visible, vapors of explosive emanating from the device are often present in the vehicle, but the current generation of trace detection equipment has not been sensitive enough to detect these low concentrations of vapor. This paper presents initial test results using the Nomadics Fido sensor for detection of VBIEDs. The sensor is a small, explosives detector with unprecedented levels of sensitivity for detection of nitroaromatic explosives. Fido utilizes fluorescence quenching of novel polymer materials to detect traces of explosive vapor emanating from targets containing explosives. These materials, developed by collaborators at the Massachusetts Institute of Technology (MIT), amplify the quenching response that occurs when molecules of explosive bind to films of the polymer. These materials have enabled development of sensors with performance approaching that of canines trained to detect explosives. The ability of the sensor to detect explosives in vehicles and on persons who have recently been in close proximity to explosives has recently been demonstrated. In these tests, simulated targets were quickly and easily detected using a Fido sensor in conjunction with both direct vapor and swipe sampling methods. The results of these tests suggest that chemical vapor sensing has utility as a means of screening vehicles for explosives at checkpoints and on patrols.

  5. Explosive laser light initiation of propellants

    DOEpatents

    Piltch, Martin S.

    1993-01-01

    A improved initiator for artillery shell using an explosively generated laser light to uniformly initiate the propellent. A small quantity of a high explosive, when detonated, creates a high pressure and temperature, causing the surrounding noble gas to fluoresce. This fluorescence is directed into a lasing material, which lases, and directs laser light into a cavity in the propellant, uniformly initiating the propellant.

  6. Explosive laser light initiation of propellants

    DOEpatents

    Piltch, M.S.

    1993-05-18

    A improved initiator for artillery shell using an explosively generated laser light to uniformly initiate the propellent. A small quantity of a high explosive, when detonated, creates a high pressure and temperature, causing the surrounding noble gas to fluoresce. This fluorescence is directed into a lasing material, which lases, and directs laser light into a cavity in the propellant, uniformly initiating the propellant.

  7. Electronic cigarette explosions involving the oral cavity.

    PubMed

    Harrison, Rebecca; Hicklin, David

    2016-11-01

    The use of electronic cigarettes (e-cigarettes) is a rapidly growing trend throughout the United States. E-cigarettes have been linked to the risk of causing explosion and fire. Data are limited on the associated health hazards of e-cigarette use, particularly long-term effects, and available information often presents conflicting conclusions. In addition, an e-cigarette explosion and fire can pose a unique treatment challenge to the dental care provider because the oral cavity may be affected heavily. In this particular case, the patient's injuries included intraoral burns, luxation injuries, and alveolar fractures. This case report aims to help clinicians gain an increased knowledge about e-cigarette design, use, and risks; discuss the risk of spontaneous failure and explosion of e-cigarettes with patients; and understand the treatment challenges posed by an e-cigarette explosion. Copyright © 2016 American Dental Association. Published by Elsevier Inc. All rights reserved.

  8. The hydrodynamics of off-center explosions. [of supernovae

    NASA Technical Reports Server (NTRS)

    Fryxell, B. A.

    1979-01-01

    The behavior of off-center supernova explosions is investigated using a two-dimensional hydrodynamic code. An important application of these calculations is the possible formation of high-velocity pulsars. The dependence of the final velocity of the collapsed remnant on the location and energy of the explosion is computed. The largest remnant velocities result from explosions located at a mass fraction of 0.5. An explosion energy 50% greater than the binding energy of the star ejects 0.51 solar masses, producing a 1.4 solar mass remnant with a velocity of 400 km/s. However, this energy must be generated in a very small region of the star in order to create the required asymmetry in the explosion. Because of this, a specific energy of about 10 to the 20th ergs/g is needed. Nuclear reactions can produce no more than about 5 x 10 to the 17th erg/g, and it is unclear how the energy produced in gravitational collapse models can be sufficiently localized. Unless a supernova mechanism can be found which can produce enough energy in a small region of the star, off-center explosions do not provide a satisfactory explanation for high-velocity pulsars.

  9. Photodegradation of Selected PCBs in the Presence of Nano-TiO2 as Catalyst and H2O2 as an Oxidant

    PubMed Central

    Dasary, Samuel S. R.; Saloni, Julia; Fletcher, Amanda; Anjaneyulu, Yerramilli; Yu, Hongtao

    2010-01-01

    Photodegradation of five strategically selected PCBs was carried out in acetonitrile/water 80:20. Quantum chemical calculations reveal that PCBs without any chlorine on ortho-positions are closer to be planar, while PCBs with at least one chlorine atoms at the ortho-positions causes the two benzene rings to be nearly perpendicular. Light-induced degradation of planar PCBs is much slower than the perpendicular ones. The use of nano-TiO2 speeds up the degradation of the planar PCBs, but slows down the degradation of the non-planar ones. The use of H2O2 speeds up the degradation of planar PCBs greatly (by >20 times), but has little effect on non-planar ones except 2,3,5,6-TCB. The relative photodegradation rate is: 2,2′,4,4′-TCB > 2,3,5,6-TCB > 2,6-DCB ≈ 3,3′,4,4′-TCB > 3,4′,5-TCB. The use of H2O2 in combination with sunlight irradiation could be an efficient and “green” technology for PCB remediation. PMID:21139872

  10. Regional Seismic Amplitude Modeling and Tomography for Earthquake-Explosion Discrimination

    DTIC Science & Technology

    2008-09-01

    explosions from earthquakes, using closely located pairs of earthquakes and explosions recorded on common, publicly available stations at test sites ...Battone et al., 2002). For example, in Figure 1 we compare an earthquake and an explosion at each of four major test sites (rows), bandpass filtered...explosions as the frequency increases. Note also there are interesting differences between the test sites , indicating that emplacement conditions (depth

  11. Infrasound Studies for Yield Estimation of HE Explosions

    DTIC Science & Technology

    2012-06-05

    AFRL-RV-PS- AFRL-RV-PS- TR-2012-0084 TR-2012-0084 INFRASOUND STUDIES FOR YIELD ESTIMATION OF HE EXPLOSIONS Paul Golden, et al...05 Mar 2010 to 05 Mar 2012 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER FA9453-10-C-0212 Infrasound Studies for Yield Estimation of HE...report we discuss the capability of estimating the yield of an explosion from infrasound signals generated by low yield chemical explosions. We used

  12. 14 CFR 417.417 - Propellants and explosives.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 417.417 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING LAUNCH SAFETY Ground Safety § 417.417 Propellants and explosives. (a) A launch operator must comply with the explosive safety criteria in part 420 of this chapter. (b) A...

  13. Muon Creation in Supernova Matter Facilitates Neutrino-Driven Explosions.

    PubMed

    Bollig, R; Janka, H-T; Lohs, A; Martínez-Pinedo, G; Horowitz, C J; Melson, T

    2017-12-15

    Muons can be created in nascent neutron stars (NSs) due to the high electron chemical potentials and the high temperatures. Because of their relatively lower abundance compared to electrons, their role has so far been ignored in numerical simulations of stellar core collapse and NS formation. However, the appearance of muons softens the NS equation of state, triggers faster NS contraction, and thus leads to higher luminosities and mean energies of the emitted neutrinos. This strengthens the postshock heating by neutrinos and can facilitate explosions by the neutrino-driven mechanism.

  14. Modeling normal shock velocity curvature relations for heterogeneous explosives

    NASA Astrophysics Data System (ADS)

    Yoo, Sunhee; Crochet, Michael; Pemberton, Steven

    2017-01-01

    The theory of Detonation Shock Dynamics (DSD) is, in part, an asymptotic method to model a functional form of the relation between the shock normal, its time rate and shock curvature κ. In addition, the shock polar analysis provides a relation between shock angle θ and the detonation velocity Dn that is dependent on the equations of state (EOS) of two adjacent materials. For the axial detonation of an explosive material confined by a cylinder, the shock angle is defined as the angle between the shock normal and the normal to the cylinder liner, located at the intersection of the shock front and cylinder inner wall. Therefore, given an ideal explosive such as PBX-9501 with two functional models determined, a unique, smooth detonation front shape ψ can be determined that approximates the steady state detonation shock front of the explosive. However, experimental measurements of the Dn(κ) relation for heterogeneous explosives such as PBXN-111 [D. K. Kennedy, 2000] are challenging due to the non-smoothness and asymmetry usually observed in the experimental streak records of explosion fronts. Out of many possibilities the asymmetric character may be attributed to the heterogeneity of the explosives; here, material heterogeneity refers to compositions with multiple components and having a grain morphology that can be modeled statistically. Therefore in extending the formulation of DSD to modern novel explosives, we pose two questions: (1) is there any simple hydrodynamic model that can simulate such an asymmetric shock evolution, and (2) what statistics can be derived for the asymmetry using simulations with defined structural heterogeneity in the unreacted explosive? Saenz, Taylor and Stewart [1] studied constitutive models for derivation of the Dn(κ) relation for porous homogeneous explosives and carried out simulations in a spherical coordinate frame. In this paper we extend their model to account for heterogeneity and present shock evolutions in heterogeneous

  15. On the Violence of High Explosive Reactions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tarver, C M; Chidester, S K

    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.

  16. Nucleosynthesis during a Thermonuclear Supernova Explosion

    NASA Astrophysics Data System (ADS)

    Panov, I. V.; Glazyrin, S. I.; Röpke, F. K.; Blinnikov, S. I.

    2018-05-01

    Supernovae are such bright objects that they can be observed even at high redshifts. Some types of such events, for example, type Ia (thermonuclear), have peculiarities of the light curve, which allows them to be used for cosmological applications. The light curve is determined by the details of the explosion dynamics and nucleosynthesis: in particular, it depends on the amount of iron-peak elements produced during the explosion. We discuss the burning processes in such objects and the peculiarities of turbulence simulations in them, which is needed for a proper hydrodynamic description of the explosion process. A direct nucleosynthesis calculation is performed for the temperature and density profiles derived in the available 3D hydrodynamic explosion simulations. We show that in the supernova progenitor model considered the calculated abundances of elements from carbon to iron-peak elements are in good agreement both with the observations and with the calculations of other authors. At the same time, no r-elements are produced even at the maximum neutron excess for this model ( Y e 0.47) due to the slow evolution of the density and temperature.

  17. Action Replay of Powerful Stellar Explosion

    NASA Astrophysics Data System (ADS)

    2008-03-01

    Astronomers have made the best ever determination of the power of a supernova explosion that was visible from Earth long ago. By observing the remnant of a supernova and a light echo from the initial outburst, they have established the validity of a powerful new method for studying supernovas. Using data from NASA's Chandra X-ray Observatory, ESA's XMM-Newton Observatory, and the Gemini Observatory, two teams of researchers studied the supernova remnant and the supernova light echo that are located in the Large Magellanic Cloud (LMC), a small galaxy about 160,000 light years from Earth. They concluded that the supernova occurred about 400 years ago (in Earth’s time frame), and was unusually bright and energetic. X-ray Image of SNR 0509-67.5 X-ray Image of SNR 0509-67.5 This result is the first time two methods - X-ray observations of a supernova remnant and optical observations of the expanding light echoes from the explosion - have both been used to estimate the energy of a supernova explosion. Up until now, scientists had only made such an estimate using the light seen soon after a star exploded, or using remnants that are several hundred years old, but not from both. "People didn't have advanced telescopes to study supernovas when they went off hundreds of years ago," said Armin Rest of Harvard University, who led the light echo observations using Gemini. "But we've done the next best thing by looking around the site of the explosion and constructing an action replay of it." People Who Read This Also Read... Milky Way's Super-efficient Particle Accelerators Caught in The Act Oldest Known Objects Are Surprisingly Immature Discovery of Most Recent Supernova in Our Galaxy NASA Unveils Cosmic Images Book in Braille for Blind Readers In 2004, scientists used Chandra to determine that a supernova remnant, known as SNR 0509-67.5 in the LMC, was a so-called Type Ia supernova, caused by a white dwarf star in a binary system that reaches a critical mass and explodes. In

  18. UV gated Raman spectroscopy for standoff detection of explosives

    NASA Astrophysics Data System (ADS)

    Gaft, M.; Nagli, L.

    2008-07-01

    Real-time detection and identification of explosives at a standoff distance is a major issue in efforts to develop defense against so-called improvised explosive devices (IED). It is recognized that the only method, which is potentially capable to standoff detection of minimal amounts of explosives is laser-based spectroscopy. LDS technique belongs to trace detection, namely to its micro-particles variety. It is based on commonly held belief that surface contamination was very difficult to avoid and could be exploited for standoff detection. We have applied gated Raman spectroscopy for detection of main explosive materials, both factory and homemade. We developed and tested a Raman system for the field remote detection and identification of minimal amounts of explosives on relevant surfaces at a distance of up to 30 m.

  19. Sensitivity of solid explosives: Minimum energy of a dangerous impact

    NASA Technical Reports Server (NTRS)

    Afanasyev, G. T.

    1986-01-01

    A method which uses initiating explosives for determining the sensitivity of solid explosives is described. The energy index of sensitivity is determined by the mechanical properties of the explosives. The results of the calculations are discussed.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tringe, J W; Molitoris, J D; Smilowitz, L

    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 frontmore » 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.« less