WorldWideScience

Sample records for events chemical explosions

  1. Chemical profiling of explosives

    NARCIS (Netherlands)

    Brust, G.M.H.

    2014-01-01

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

  2. Chemical explosive stimulation

    Energy Technology Data Exchange (ETDEWEB)

    LaRocca, S.J.; McLamore, R.T.; Spencer, A.M. Jr.

    1974-02-01

    A safe, reliable chemical explosive fracturing process has been demonstrated and prototype equipment for its use has been successfully field tested.Called the Astro-Flow II process, it utilizes a highly energetic, hydrazine-based family of liquid explosives known as Astrolite. A unique property of these explosives is that they can be divided into 2 nonexplosive pumpable components that can be handled safely. The 2 components are pumped independently and simultaneously into the well and blended together downhole to form the explosive which is circulated in place or displaced into formation fractures. Explosive hazards to surface equipment and personnel are eliminated. Extensive testing of the physical and chemical stability of the mixed explosive indicates that the material can be reliable and safely used at elevated temperatures, pressures, and in the adverse chemical environment often found in deep oil and gas wells. These tests of prototype equipment proved that the 2 components could be independently pumped with precision and blended together to form the desired explosive formulation. How the process works is described.

  3. Terrorist Event Training in US Medical Schools. A Survey of Chemical, Biologic, Radiologic, Nuclear, and High-Yield Explosives Training in US Medical Schools.

    Science.gov (United States)

    Feeney, James M; Ziegler, Kristina; Armstrong, Jessica M; Shapiro, David

    2015-01-01

    September 11, 2001 saw the dawn of the US-led global war on terror, a combined diplomatic, military, social, and cultural war on terrorist activities. Chemical, biological, radiological, nuclear, and high-yield explosives (CBRNE), as a group of tactics, are often the preferred weapons of terrorists across the globe. We undertook a survey of US medical schools to determine what their self-reported level of training for terrorist events encompasses during the four years of undergraduate medical education. We surveyed 170 medical schools in the US and Puerto Rico using a five-question, internet-based survey, followed by telephone calls to curriculum offices for initial nonresponders. We used simple descriptive statistics to analyze the data. A majority of US medical schools that completed the survey (79 schools or 65.3%) have no required lecture or course on CBRNE or terrorist activities during the first or second year (preclinical years). Ninety-eight out of the 121 respondents (81.0%), however, believed that CBRNE training was either very important or somewhat important, as reflected in survey answers. Most physician educators believe that training in CBRNE is important; however this belief has not resulted in widespread acceptance of a CBRNE curriculum in US medical schools.

  4. Data base of chemical explosions in Kazakhstan

    Energy Technology Data Exchange (ETDEWEB)

    Demin, V.N. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Malahova, M.N. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Martysevich, P.N. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Mihaylova, N.N. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Nurmagambetov, A. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Kopnichev, Yu.F. D. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Edomin, V.I. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan)

    1996-12-01

    Within the bounds of this report, the following works were done: (1) Information about explosion quarries, located in Southern, Eastern and Northern Kasakstan was summarized. (2) The general information about seismicity of areas of location of explosion quarries was adduced. (3) The system of observation and seismic apparatus, recording the local earthquakes and quarry explosions at the territory of Kazakstan were described. (4) Data base of quarry explosions, that were carried out in Southern, Eastern and Northern Kazakstan during 1995 and first half of 1996 year was adduced. (5) Upon the data of registration of explosions in Southern Kazakstan the correlative dependences between power class of explosions and summary weight of charge were constructed. (6) Seismic records of quarry explosions were adduced. It is necessary to note, that the collection of data about quarry explosions in Kazakstan in present time is very difficult task. Organizations, that makes these explosions, are always suffering reorganizations and sometimes it is actually impossible to receive all the necessary information. Some quarries are situated in remote, almost inaccessible regions, and within the bounds of supplier financing not the every quarry was in success to visit. So the present data base upon the chemical explosions for 1995 is not full and in further it`s expansion is possible.

  5. Source analysis of underground chemical explosions

    Science.gov (United States)

    Chiang, A.; Ford, S. R.; Pitarka, A.

    2016-12-01

    Several physical mechanisms have been proposed to explain the generation of S-waves from underground explosions, such as asymmetries in the source, release of tectonic pre-stress, interactions with the free-surface, and heterogeneities in the Earth. An accurate description of the explosion source processes is an important step towards understanding which of these plausible mechanisms are actively contributing to the generation of S-waves and under what conditions. In this study we investigate the sensitivity of far-field waveforms to seismic source mechanisms by comparing simulated and recorded data from underground chemical explosions performed during the Source Physics Experiment. We use both forward and inverse waveform modeling approaches to estimate the source properties of the explosions, and compare solutions using different velocity models and at different frequency bands and distances. 1D and 3D velocity models are used to characterize wave propagation between the source and receiver. The 3D velocity models are constructed using available geological and geophysical data, and ambient noise seismic tomography. The 3D Green's functions are computed using a numerical finite-difference approach. We will investigate the sensitivity of far-field ground motion to different levels of source complexities, such as a single isotropic source or complex sources with non-isotropic radiation in the frequency range of 0.5 to 6 Hz.

  6. 46 CFR 189.25-47 - Chemical and explosive hazards.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Chemical and explosive hazards. 189.25-47 Section 189.25... INSPECTION AND CERTIFICATION Inspection for Certification § 189.25-47 Chemical and explosive hazards. (a) The marine inspector shall inspect every chemistry laboratory, scientific laboratory, and chemical storeroom...

  7. Explosive Infrasonic Events: Sensor Comparison Experiment (SCE)

    Energy Technology Data Exchange (ETDEWEB)

    Schnurr, J. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Garces, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rodgers, A. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-02-06

    SCE (sensor comparison experiment) 1 through 4 consists of a series of four controlled above-ground explosions designed to provide new data for overpressure propagation. Infrasound data were collected by LLNL iPhones and other sensors. Origin times, locations HOB, and yields are not being released at this time and are therefore not included in this report. This preliminary report will be updated as access to additional data changes, or instrument responses are determined.

  8. Seismic and source characteristics of large chemical explosions. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Adushkin, V.V.; Kostuchenko, V.N.; Pernik, L.M.; Sultanov, D.D.; Zcikanovsky, V.I.

    1995-01-01

    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. In 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.

  9. Supersensitive fingerprinting of explosives by chemically modified nanosensors arrays

    Science.gov (United States)

    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.

  10. Characteristics of regional seismic waves from large explosive events including Korean nuclear explosions

    Science.gov (United States)

    Jo, Eunyoung; Lee, Ha-sung

    2015-04-01

    Three North Korean underground nuclear explosion (UNE) tests were conducted in 2006, 2009 and 2013. Discrimination of explosions from natural earthquakes is important in monitoring the seismic activity in the Korean Peninsula. The UNEs were well recorded by dense regional seismic networks in South Korea. The UNEs provide unique regional seismic waveforms with high signal-to-noise ratios. However, the continental crust in the Korean Peninsula changes abruptly into a transitional structure between continental and oceanic crusts across the eastern coast. The complex geological and tectonic structures around the Korean Peninsula cause significant variations in regional waveforms. Outstanding question is whether conventional discrimination techniques can be applicable for explosions including the North Korean UNEs. P/S amplitude ratios are widely used for seismic discrimination. To understand the regional shear-energy composition, we analyze the frequency contents of waveforms. The shear-energy contents for the UNEs are compared with those for natural earthquakes with comparable magnitudes. The result shows that the UNEs are successfully discriminated from earthquakes in the Korean Peninsula. We also analyze the explosive events from North Korean not UNEs to test the applicability of the discrimination technique. The result of high frequency Pn/Sn regional discrimination in the explosions show that as magnitude of event is smaller, available distance of discrimination is decreased particularly in high frequency range. The poor signal to noise ratio of Pn phase in the explosions, and inefficient propagation of Sn phase in the Western part of the peninsula frustrate Pn/Sn discriminant, while the UNEs show good performance using both discriminants because of propagation path effects in the eastern part of the peninsula.

  11. Reduction of Allowed Inventory When Chemicals are Located in Close Proximity with Explosives

    Energy Technology Data Exchange (ETDEWEB)

    Chong, Y P; Nguyen, S N

    2006-09-27

    The objective of this report is to determine the allowed inventory of chemicals stored in the same bay, building or magazine, i.e., in close proximity, with high explosives (HE) that would, in the event of an accident, result in acceptable risks to colocated workers and the public.

  12. Ascertaining the impact of catastrophic events on dengue outbreak: The 2014 gas explosions in Kaohsiung, Taiwan.

    Science.gov (United States)

    Hsieh, Ying-Hen

    2017-01-01

    Infectious disease outbreaks often occur in the aftermath of catastrophic events, either natural or man-made. While natural disasters such as typhoons/hurricanes, flooding and earthquakes have been known to increase the risk of infectious disease outbreak, the impact of anthropogenic disasters is less well-understood. Kaohsiung City is located in southern Taiwan, where most dengue outbreaks had occurred in the past two decades. It is also the center of petrochemical industry in Taiwan with pipelines running underneath city streets. Multiple underground gas explosions occurred in Kaohsiung in the evening of July 31, 2014 due to chemical leaks in the pipelines. The explosions caused 32 deaths, including five firefighters and two volunteer firefighters, and injured 321 persons. Historically, dengue outbreaks in southern Taiwan occurred mostly in small numbers of around 2000 cases or less, except in 2002 with over 5000 cases. However, in the months after the gas explosions, the city reported 14528 lab-confirmed dengue cases from August to December. To investigate the possible impact, if any, of the gas explosions on this record-breaking dengue outbreak, a simple mathematical model, the Richards model, is utilized to study the temporal patterns of the spread of dengue in the districts of Kaohsiung in the proximity of the explosion sites and to pinpoint the waves of infections that had occurred in each district in the aftermath of the gas explosions. The reproduction number of each wave in each district is also computed. In the aftermath of the gas explosions, early waves occurred 4-5 days (which coincides with the minimum of human intrinsic incubation period for dengue) later in districts with multiple waves. The gas explosions likely impacted the timing of the waves, but their impact on the magnitude of the 2014 outbreak remains unclear. The modeling suggests the need for public health surveillance and preparedness in the aftermath of future disasters.

  13. VideoSAR collections to image underground chemical explosion surface phenomena

    Science.gov (United States)

    Yocky, David A.; Calloway, Terry M.; Wahl, Daniel E.

    2017-05-01

    Fully-polarimetric X-band (9.6 GHz center frequency) VideoSAR with 0.125-meter ground resolution flew collections before, during, and after the fifth Source Physics Experiment (SPE-5) underground chemical explosion. We generate and exploit synthetic aperture RADAR (SAR) and VideoSAR products to characterize surface effects caused by the underground explosion. To our knowledge, this has never been done. Exploited VideoSAR products are "movies" of coherence maps, phase-difference maps, and magnitude imagery. These movies show two-dimensional, time-varying surface movement. However, objects located on the SPE pad created unwanted, vibrating signatures during the event which made registration and coherent processing more difficult. Nevertheless, there is evidence that dynamic changes are captured by VideoSAR during the event. VideoSAR provides a unique, coherent, time-varying measure of surface expression of an underground chemical explosion.

  14. Cavity Radius Scaling for Chemical Explosions in Granite

    Science.gov (United States)

    Stroujkova, A. F.; Vorobiev, O.; Carnevale, M.

    2015-12-01

    It was long argued that the far-field seismic amplitudes from explosions are determined by the volume change in the source region, mainly due to a formation of the explosive cavities (e.g. Denny and Johnson, 1991). Weston Geophysical performed measurements of the cavities left by small chemical explosions in hard rock in New England. The comparison of the measured cavity sizes with historical data from nuclear and chemical explosions in hard rock (e.g. granite) shows that the cavity radii scale as W1/3 and appear to be depth independent because the rock strength significantly exceeds the overburden pressure for all possible explosion depths. The cavity sizes produced by nuclear explosions in softer rock (e.g. alluvium) deviate from the cubic root scaling and depend on the confining pressure. Cavity size calculations as a function of yield using hydrodynamic simulations with GEODYN, an Eulerian hydrodynamic code developed at Lawrence Livermore National Laboratory, support these observations. We investigate the effects of the cavity size as well as the extent of the damage zones on seismic radiation.

  15. High explosive characterization for the dice throw event

    Energy Technology Data Exchange (ETDEWEB)

    Helm, F.; Finger, M.; Hayes, B.; Lee, E.; Cheung, H.; Walton, J.

    1976-06-16

    An equation of state for detonation products was developed to describe the detonation of large charges of ammonium nitrate/fuel oil (ANFO). The equation of state will be used to predict air-blast and ground-motion effects in the Dice Throw Event. The explosive performance of ANFO is highly dependent on charge size. The equation developed from this work is applicable to heavily confined detonations 101.6 mm in diameter or larger. The equation of state is based on results from experiments in cylinders and hemispheres, and a large field test. The report contains a detailed discussion of the diagnostic and initiation techniques used in these experiments.

  16. Weapons of mass destruction: Overview of the CBRNEs (Chemical, Biological, Radiological, Nuclear, and Explosives).

    Science.gov (United States)

    Prockop, Leon D

    2006-11-01

    The events of September 11, 2001, made citizens of the world acutely aware of disasters consequent to present-day terrorism. This is a war being waged for reasons obscure to many of its potential victims. The term "NBCs" was coined in reference to terrorist weapons of mass destruction, i.e., nuclear, biological and chemical. The currently accepted acronym is "CBRNE" which includes Chemical, Biological, Radiological, Nuclear, and Explosive weapons. Non-nuclear explosives are the most common terrorist weapon now in use. Nuclear and radiological weapons are beyond the scope of this publication, which focuses on the "CBEs", i.e. chemical, biological and explosive weapons. Although neurologists will not be the first responders to CBEs, they must know about the neurological effects in order to provide diagnosis and treatment to survivors. Neurological complications of chemical, biological and explosive weapons which have or may be used by terrorists are reviewed by international experts in this publication. Management and treatment profiles are outlined.

  17. Liquid contents verification for explosives, chemical agents, and dissolved narcotics

    Science.gov (United States)

    Kumar, Sankaran; McMichael, W. Casey; Magnuson, Erik E.; Lee, Young K.; Moeller, Charles R.; Czipott, Peter V.; Rayner, Timothy J.; Newman, David E.; Wroblewski, Dariusz

    2001-02-01

    An increasingly important need today is to guard against terrorist attacks at key locations such as airports and public buildings. Liquid explosives can avoid detection at security checkpoints by being concealed as beverages or other benign liquids. Magnetic resonance (MR) offers a safe, non-invasive technology for probing and classifying the liquid contents inside sealed non-metallic containers or packages. Quantum Magnetics has developed a Liquid Explosives Screening System or `Bottle Scanner' to screen for liquid explosives and flammables, described at an earlier SPIE conference in 1996. Since then, the Bottle Scanner's performance has been significantly improved by the incorporation of neural network-based liquid classification. Recently we have shown that the incorporation of additional discrimination parameters can further enhance liquid classification. In addition to screening for explosives and flammables, the Bottle Scanner can be effective against chemical agents, many of which contain fluorine or phosphorous, both of which have MR signatures. Finally, we have evidence that the Bottle Scanner may also be able to detect narcotics dissolved in beverages, one of the methods used to smuggle narcotics across international borders. The development of the Bottle Scanner has been funded by the Federal Aviation Administration.

  18. Health complaints after a malodorous chemical explosion: a longitudinal study.

    Science.gov (United States)

    Tjalvin, G; Lygre, S H L; Hollund, B E; Moen, B E; Bråtveit, M

    2015-04-01

    Physical and psychological symptoms are prevalent in populations recently affected by industrial accidents. Follow-up studies of human health effects are scarce, and as most of them focus on residents, little is known about the long-term health effects among workers exposed to malodorous emissions following a chemical explosion. To assess whether subjective health complaints (SHC) among workers declined over a 4-year period after an oil tank explosion that emitted malodorous sulphurous compounds. A longitudinal survey from 2008 (18 months after the explosion) to 2012, performed using the SHC inventory. Questionnaire data were analysed using a linear mixed effects model. There was a decrease in SHCs among the exposed workers, but they still had significantly more subjective neurological symptoms (P explosion. Although there was a downward trend in SHCs among exposed workers in the follow-up period, they reported more subjective neurological complaints than controls. Symptoms may be mediated by perceived pollution and health risk perception, and adaptation or anxiety may cause a chronic effect, manifested by a dysfunctional and persistent neuropsychological response. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. SNhunt151: an explosive event inside a dense cocoon

    Science.gov (United States)

    Elias-Rosa, N.; Benetti, S.; Cappellaro, E.; Pastorello, A.; Terreran, G.; Morales-Garoffolo, A.; Howerton, S. C.; Valenti, S.; Kankare, E.; Drake, A. J.; Djorgovski, S. G.; Tomasella, L.; Tartaglia, L.; Kangas, T.; Ochner, P.; Filippenko, A. V.; Ciabattari, F.; Geier, S.; Howell, D. A.; Isern, J.; Leonini, S.; Pignata, G.; Turatto, M.

    2018-01-01

    SNhunt151 was initially classified as a supernova (SN) impostor (nonterminal outburst of a massive star). It exhibited a slow increase in luminosity, lasting about 450 d, followed by a major brightening that reaches MV ≈ -18 mag. No source is detected to MV ≳ -13 mag in archival images at the position of SNhunt151 before the slow rise. Low-to-mid-resolution optical spectra obtained during the pronounced brightening show very little evolution, being dominated at all times by multicomponent Balmer emission lines, a signature of interaction between the material ejected in the new outburst and the pre-existing circumstellar medium. We also analyzed mid-infrared images from the Spitzer Space Telescope, detecting a source at the transient position in 2014 and 2015. Overall, SNhunt151 is spectroscopically a Type IIn SN, somewhat similar to SN 2009ip. However, there are also some differences, such as a slow pre-discovery rise, a relatively broad light-curve peak showing a longer rise time (˜50 d) and a slower decline, along with a negligible change in the temperature around the peak (T ≤ 104 K). We suggest that SNhunt151 is the result of an outburst, or a SN explosion, within a dense circumstellar nebula, similar to those embedding some luminous blue variables like η Carinae and originating from past mass-loss events.

  20. Chemical, Biological, and Explosive Sensors for Field Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Kyle, Manuel Manard, Stephan Weeks

    2009-01-31

    Special Technologies Laboratory (STL) is developing handheld chemical, biological, and explosive (CBE) detection systems and sensor motes for wireless networked field operations. The CBE sensors are capable of detecting and identifying multiple targeted toxic industrial chemicals (TICs) and high-explosive vapor components. The CBE devices are based on differential mobility spectrometry (DMS) coupled with fast gas chromatography (GC) or mass spectrometry. The systems all include the concepts of: 1. Direct air/particulate “smart” sampling 2. Selective, continuous real-time (~1 sec) alert monitoring using DMS 3. Highly selective, rapid dual technology separation/verification analysis The biosensor technology is based on Raman aerosol particle flow cytometry for target detection and identification. Monitoring and identifying trace level chemical vapors directly from ambient air will allow First Responders to quickly adapt situational response strategies and personal protective equipment needs to the specific response scenario being encountered. First Responders require great confidence in the measurements and ability of a given system to detect CBE below threshold levels without interferences. The concept of determining the background matrix in near real-time to allow subsequent automated field-programmable method selection and cueing of high-value assets in a wide range of environs will be presented. This provides CBE information for decisions prior to First Responders entering the response site or sending a portable mobile unit for a remote site survey of the hazards. The focus is on real-time information needed by those responsible for emergency response and national security.

  1. A comparative evaluation of explosion hazards in chemical and mechanical pulp bleaching systems

    Science.gov (United States)

    Peter W. Hart; Alan W. Rudie

    2010-01-01

    Over the past several years, at least three pulp mills in North America have experienced catastrophic events that resulted in the explosion of pumps, mixers, and tanks. All these mills were using 50% concentration hydrogen peroxide at the site of the explosions. In at least two instances, alkali catalyzed decomposition of peroxide is implicated in the explosion....

  2. Hand-Held Devices Detect Explosives and Chemical Agents

    Science.gov (United States)

    2010-01-01

    Ion Applications Inc., of West Palm Beach, Florida, partnered with Ames Research Center through Small Business Innovation Research (SBIR) agreements to develop a miniature version ion mobility spectrometer (IMS). While NASA was interested in the instrument for detecting chemicals during exploration of distant planets, moons, and comets, the company has incorporated the technology into a commercial hand-held IMS device for use by the military and other public safety organizations. Capable of detecting and identifying molecules with part-per-billion sensitivity, the technology now provides soldiers with portable explosives and chemical warfare agent detection. The device is also being adapted for detecting drugs and is employed in industrial processes such as semiconductor manufacturing.

  3. Blast event simulation for a vehicle subjected to an explosion

    NARCIS (Netherlands)

    Zhang, G.; Vlahopoulos, N.; Goetz, R.; Velde, R. van de

    2007-01-01

    One of the main threats to military vehicles originates from blasts. In order to improve the survivability of the occupants it is important to design a military vehicle for increased occupant safety. Simulation technology that combines modeling of the blast loads from an explosion, the response of

  4. Generation of low-frequency electric and magnetic fields during large- scale chemical and nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Adushkin, V.V. [Academy of Sciences, Moscow (Russian Federation). Inst. for Dynamics of the Geospheres; Dubinya, V.A.; Karaseva, V.A.; Soloviev, S.P.; Surkov, V.V. [Lawrence Livermore National Lab., CA (United States)

    1995-06-01

    We discuss the main parameters of the electric field in the surface layer of the atmosphere and the results of the investigations of the natural electric field variations. Experimental investigations of the electromagnetic field for explosions in air are presented. Electromagnetic signals generated by underground nuclear and chemical explosions are discussed and explosions for 1976--1991 are listed. Long term anomalies of the earth`s electromagnetic field in the vicinity of underground explosions were also investigated. Study of the phenomenon of the irreversible shock magnetization showed that in the zone nearest to the explosion the quasistatic magnetic field decreases in inverse proportion to the distance.

  5. An exemplary case of a bromine explosion event linked to cyclone development in the Arctic

    Science.gov (United States)

    Blechschmidt, A.-M.; Richter, A.; Burrows, J. P.; Kaleschke, L.; Strong, K.; Theys, N.; Weber, M.; Zhao, X.; Zien, A.

    2016-02-01

    Intense, cyclone-like shaped plumes of tropospheric bromine monoxide (BrO) are regularly observed by GOME-2 on board the MetOp-A satellite over Arctic sea ice in polar spring. These plumes are often transported by high-latitude cyclones, sometimes over several days despite the short atmospheric lifetime of BrO. However, only few studies have focused on the role of polar weather systems in the development, duration and transport of tropospheric BrO plumes during bromine explosion events. The latter are caused by an autocatalytic chemical chain reaction associated with tropospheric ozone depletion and initiated by the release of bromine from cold brine-covered ice or snow to the atmosphere. In this manuscript, a case study investigating a comma-shaped BrO plume which developed over the Beaufort Sea and was observed by GOME-2 for several days is presented. By making combined use of satellite data and numerical models, it is shown that the occurrence of the plume was closely linked to frontal lifting in a polar cyclone and that it most likely resided in the lowest 3 km of the troposphere. In contrast to previous case studies, we demonstrate that the dry conveyor belt, a potentially bromine-rich stratospheric air stream which can complicate interpretation of satellite retrieved tropospheric BrO, is spatially separated from the observed BrO plume. It is concluded that weather conditions associated with the polar cyclone favoured the bromine activation cycle and blowing snow production, which may have acted as a bromine source during the bromine explosion event.

  6. An exemplary case of a bromine explosion event linked to cyclone development in the Arctic

    Directory of Open Access Journals (Sweden)

    A.-M. Blechschmidt

    2016-02-01

    Full Text Available Intense, cyclone-like shaped plumes of tropospheric bromine monoxide (BrO are regularly observed by GOME-2 on board the MetOp-A satellite over Arctic sea ice in polar spring. These plumes are often transported by high-latitude cyclones, sometimes over several days despite the short atmospheric lifetime of BrO. However, only few studies have focused on the role of polar weather systems in the development, duration and transport of tropospheric BrO plumes during bromine explosion events. The latter are caused by an autocatalytic chemical chain reaction associated with tropospheric ozone depletion and initiated by the release of bromine from cold brine-covered ice or snow to the atmosphere. In this manuscript, a case study investigating a comma-shaped BrO plume which developed over the Beaufort Sea and was observed by GOME-2 for several days is presented. By making combined use of satellite data and numerical models, it is shown that the occurrence of the plume was closely linked to frontal lifting in a polar cyclone and that it most likely resided in the lowest 3 km of the troposphere. In contrast to previous case studies, we demonstrate that the dry conveyor belt, a potentially bromine-rich stratospheric air stream which can complicate interpretation of satellite retrieved tropospheric BrO, is spatially separated from the observed BrO plume. It is concluded that weather conditions associated with the polar cyclone favoured the bromine activation cycle and blowing snow production, which may have acted as a bromine source during the bromine explosion event.

  7. Behavioural and Genetic Evidence for C. elegans' Ability to Detect Volatile Chemicals Associated with Explosives

    OpenAIRE

    Chunyan Liao; Andrew Gock; Michelle Michie; Bethany Morton; Alisha Anderson; Stephen Trowell

    2010-01-01

    BACKGROUND: Automated standoff detection and classification of explosives based on their characteristic vapours would be highly desirable. Biologically derived odorant receptors have potential as the explosive recognition element in novel biosensors. Caenorhabditis elegans' genome contains over 1,000 uncharacterised candidate chemosensory receptors. It was not known whether any of these respond to volatile chemicals derived from or associated with explosives. METHODOLOGY/PRINCIPAL FINDINGS: W...

  8. Behavioural and genetic evidence for C. elegans' ability to detect volatile chemicals associated with explosives.

    Science.gov (United States)

    Liao, Chunyan; Gock, Andrew; Michie, Michelle; Morton, Bethany; Anderson, Alisha; Trowell, Stephen

    2010-09-07

    Automated standoff detection and classification of explosives based on their characteristic vapours would be highly desirable. Biologically derived odorant receptors have potential as the explosive recognition element in novel biosensors. Caenorhabditis elegans' genome contains over 1,000 uncharacterised candidate chemosensory receptors. It was not known whether any of these respond to volatile chemicals derived from or associated with explosives. We assayed C. elegans for chemotactic responses to chemical vapours of explosives and compounds associated with explosives. C. elegans failed to respond to many of the explosive materials themselves but showed strong chemotaxis with a number of compounds associated with commercial or homemade explosives. Genetic mutant strains were used to identify the likely neuronal location of a putative receptor responding to cyclohexanone, which is a contaminant of some compounded explosives, and to identify the specific transduction pathway involved. Upper limits on the sensitivity of the nematode were calculated. A sensory adaptation protocol was used to estimate the receptive range of the receptor. The results suggest that C. elegans may be a convenient source of highly sensitive, narrowly tuned receptors to detect a range of explosive-associated volatiles.

  9. Behavioural and genetic evidence for C. elegans' ability to detect volatile chemicals associated with explosives.

    Directory of Open Access Journals (Sweden)

    Chunyan Liao

    Full Text Available BACKGROUND: Automated standoff detection and classification of explosives based on their characteristic vapours would be highly desirable. Biologically derived odorant receptors have potential as the explosive recognition element in novel biosensors. Caenorhabditis elegans' genome contains over 1,000 uncharacterised candidate chemosensory receptors. It was not known whether any of these respond to volatile chemicals derived from or associated with explosives. METHODOLOGY/PRINCIPAL FINDINGS: We assayed C. elegans for chemotactic responses to chemical vapours of explosives and compounds associated with explosives. C. elegans failed to respond to many of the explosive materials themselves but showed strong chemotaxis with a number of compounds associated with commercial or homemade explosives. Genetic mutant strains were used to identify the likely neuronal location of a putative receptor responding to cyclohexanone, which is a contaminant of some compounded explosives, and to identify the specific transduction pathway involved. Upper limits on the sensitivity of the nematode were calculated. A sensory adaptation protocol was used to estimate the receptive range of the receptor. CONCLUSIONS/SIGNIFICANCE: The results suggest that C. elegans may be a convenient source of highly sensitive, narrowly tuned receptors to detect a range of explosive-associated volatiles.

  10. Physical Constraints on Seismic Waves from Chemical and Nuclear Explosions

    Science.gov (United States)

    1992-04-22

    dwell indicative of spall. Solid and heavy dashed lines are bounds on the depth of the spall zone. 107 Q LUJ 0 02 oo XLUj 0 0 2 (1) Cc 2t S-3NAO...explosives in the bottom of the hole and 57 kg of ammonium nitrate fuel oil ( ANFO ). The explo.;ives were initiated from the top of the hole. The charges...borehole pressure can bc expressed as a percentage of the explosive detonation pressure although variations can be quite high for ANFO (30-70

  11. Explosion of limit cycles and chaotic waves in a simple nonlinear chemical system

    DEFF Research Database (Denmark)

    Brøns, Morten; Sturis, Jeppe

    2001-01-01

    A model of an autocatalytic chemical reaction was employed to study the explosion of limit cycles and chaotic waves in a nonlinear chemical system. The bifurcation point was determined using asymptotic analysis and perturbations. Scaling laws for amplitude and period were derived. A strong...

  12. Laser-based standoff detection of surface-bound explosive chemicals

    Science.gov (United States)

    Huestis, David L.; Smith, Gregory P.; Oser, Harald

    2010-04-01

    Avoiding or minimizing potential damage from improvised explosive devices (IEDs) such as suicide, roadside, or vehicle bombs requires that the explosive device be detected and neutralized outside its effective blast radius. Only a few seconds may be available to both identify the device as hazardous and implement a response. As discussed in a study by the National Research Council, current technology is still far from capable of meeting these objectives. Conventional nitrocarbon explosive chemicals have very low vapor pressures, and any vapors are easily dispersed in air. Many pointdetection approaches rely on collecting trace solid residues from dust particles or surfaces. Practical approaches for standoff detection are yet to be developed. For the past 5 years, SRI International has been working toward development of a novel scheme for standoff detection of explosive chemicals that uses infrared (IR) laser evaporation of surfacebound explosive followed by ultraviolet (UV) laser photofragmentation of the explosive chemical vapor, and then UV laser-induced fluorescence (LIF) of nitric oxide. This method offers the potential of long standoff range (up to 100 m or more), high sensitivity (vaporized solid), simplicity (no spectrometer or library of reference spectra), and selectivity (only nitrocompounds).

  13. Explosive Events in the Quiet Sun: Extreme Ultraviolet Imaging Spectroscopy Instrumentation and Observations

    Science.gov (United States)

    Rust, Thomas Ludwell

    Explosive event is the name given to slit spectrograph observations of high spectroscopic velocities in solar transition region spectral lines. Explosive events show much variety that cannot yet be explained by a single theory. It is commonly believed that explosive events are powered by magnetic reconnection. The evolution of the line core appears to be an important indicator of which particular reconnection process is at work. The Multi-Order Solar Extreme Ultraviolet Spectrograph (MOSES) is a novel slitless spectrograph designed for imaging spectroscopy of solar extreme ultraviolet (EUV) spectral lines. The spectrograph design forgoes a slit and images instead at three spectral orders of a concave grating. The images are formed simultaneously so the resulting spatial and spectral information is co-temporal over the 20' x 10' instrument field of view. This is an advantage over slit spectrographs which build a field of view one narrow slit at a time. The cost of co-temporal imaging spectroscopy with the MOSES is increased data complexity relative to slit spectrograph data. The MOSES data must undergo tomographic inversion for recovery of line profiles. I use the unique data from the MOSES to study transition region explosive events in the He ii 304 A spectral line. I identify 41 examples of explosive events which include 5 blue shifted jets, 2 red shifted jets, and 10 bi-directional jets. Typical doppler speeds are approximately 100kms-1. I show the early development of one blue jet and one bi-directional jet and find no acceleration phase at the onset of the event. The bi-directional jets are interesting because they are predicted in models of Petschek reconnection in the transition region. I develop an inversion algorithm for the MOSES data and test it on synthetic observations of a bi-directional jet. The inversion is based on a multiplicative algebraic reconstruction technique (MART). The inversion successfully reproduces synthetic line profiles. I then use

  14. Prediction of injuries caused by explosive events: A case study of a hand grenade incident in South Africa

    CSIR Research Space (South Africa)

    Whyte, TN

    2008-11-01

    Full Text Available injuries when the subject is in very close proximity to the explosive charge is still unknown. Further such case studies and research into injury mechanisms and injury criteria are necessary to enable injuries caused by explosive events to be accurately...

  15. Psychosocial risk factors for depressive symptoms after the AZF chemical factory explosion in Toulouse, France.

    Science.gov (United States)

    Rivière, Stéphanie; Albessard, Artus; Gardette, Virginie; Lapierre-Duval, Karine; Schwoebel, Valérie; Lang, Thierry

    2010-12-01

    On 21 September 2001, a huge explosion occurred in a chemical plant in Toulouse. The hypothesis of the study was that the level of depressive symptoms after an industrial disaster would be related to the intensity of exposure and the characteristics of the exposed population, as well as to the consequences of the disaster during the following months. A random sample of the population living close to the plant at the time of the explosion was included in a cross-sectional study, and 811 persons aged > 18 years were interviewed at home. The depressive symptoms score was analysed by gender in relation to characteristics of the population before the explosion, immediate exposure to the explosion and post-trauma factors. The mean depressive symptoms scores (± SD) 18 months after the explosion were 17.8 (± 1) in women and 13.5 (± 1) in men. Age >  45 years and psychiatric treatment in the previous year; high immediate exposure (proximity to the site at the time of the explosion explosion, individual vulnerability, exposure and post-trauma factors were associated with depressive symptoms. All three sets of factors need to be taken into account when planning a response to a disaster and reducing the psychological aftermath.

  16. Atmospheric Pressure Chemical Ionization Sources Used in The Detection of Explosives by Ion Mobility Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Waltman, Melanie J. [New Mexico Inst. of Mining and Technology, Socorro, NM (United States)

    2010-05-01

    Explosives detection is a necessary and wide spread field of research. From large shipping containers to airline luggage, numerous items are tested for explosives every day. In the area of trace explosives detection, ion mobility spectrometry (IMS) is the technique employed most often because it is a quick, simple, and accurate way to test many items in a short amount of time. Detection by IMS is based on the difference in drift times of product ions through the drift region of an IMS instrument. The product ions are created when the explosive compounds, introduced to the instrument, are chemically ionized through interactions with the reactant ions. The identity of the reactant ions determines the outcomes of the ionization process. This research investigated the reactant ions created by various ionization sources and looked into ways to manipulate the chemistry occurring in the sources.

  17. Near-field non-radial motion generation from underground chemical explosions in jointed granite

    Science.gov (United States)

    Vorobiev, Oleg; Ezzedine, Souheil; Hurley, Ryan

    2018-01-01

    This paper describes analysis of non-radial ground motion generated by chemical explosions in a jointed rock formation during the Source Physics Experiment (SPE). Such motion makes it difficult to discriminate between various subsurface events such as explosions, implosions (i.e. mine collapse) and earthquakes. We apply 3-D numerical simulations to understand experimental data collected during the SPEs. The joints are modelled explicitly as compliant thin inclusions embedded into the rock mass. Mechanical properties of the rock and the joints as well as the joint spacing and orientation are inferred from experimental test data, and geophysical and geological characterization of the SPE site which is dominantly Climax Stock granitic outcrop. The role of various factors characterizing the joints such as joint spacing, frictional properties, orientation and persistence in generation of non-radial motion is addressed. The joints in granite at the SPE site are oriented in nearly orthogonal directions with two vertical sets dipping at 70-80 degrees with the same strike angle, one vertical set almost orthogonal to the first two and one shallow angle joint set dipping 15 degrees. In this study we establish the relationship between the joint orientation and azimuthal variations in the polarity of the observed shear motion. The majority of the shear motion is generated due to the effects of non-elastic sliding on the joints near the source, where the wave can create significant shear stress to overcome the cohesive forces at the joints. Near the surface the joints are less confined and are subject to sliding when the pressure waves are reflected. In the far field, where the cohesive forces on the joints cannot be overcome, additional shear motion can be generated due to elastic anisotropy of the rock mass given by preferred spatial orientations of compliant joints.

  18. Forensic analysis methodology for thermal and chemical characterization of homemade explosives

    Energy Technology Data Exchange (ETDEWEB)

    Nazarian, Ashot; Presser, Cary, E-mail: cpresser@nist.gov

    2014-01-20

    Highlights: • Identification of homemade explosives (HME) is critical for determining the origin of explosive precursor materials. • A novel laser-heating technique was used to obtain the thermal/chemical signatures of HME precursor materials. • Liquid-fuel saturation of the pores of a solid porous oxidizer affected the total specific heat release. • Material thermal signatures were dependent on sample mass and heating rate. • This laser-heating technique can be a useful diagnostic tool for characterizing the thermochemical behavior of HMEs. - Abstract: Forensic identification of homemade explosives is critical for determining the origin of the explosive materials and precursors, and formulation procedures. Normally, the forensic examination of the pre- and post-blast physical evidence lacks specificity for homemade-explosive identification. The focus of this investigation was to use a novel measurement technique, referred to as the laser-driven thermal reactor, to obtain the thermal/chemical signatures of homemade-explosive precursor materials. Specifically, nitromethane and ammonium nitrate were studied under a variety of operating conditions and protocols. Results indicated that liquid-fuel saturation of the internal pores of a solid particle oxidizer appear to be a limiting parameter for the total specific heat release during exothermic processes. Results also indicated that the thermal signatures of these materials are dependent on sample mass and heating rate, for which this dependency may not be detectable by other commercially available thermal analysis techniques. This study has demonstrated that the laser-driven thermal reactor can be a useful diagnostic tool for characterizing the thermal and chemical behavior of trace amounts of homemade-explosive materials.

  19. A new type of functional chemical sensitizer MgH2 for improving pressure desensitization resistance of emulsion explosives

    Science.gov (United States)

    Cheng, Y. F.; Yan, S. L.; Ma, H. H.; Shen, Z. W.; Liu, R.

    2016-03-01

    In millisecond-delay blasting and deep water blasting projects, traditional emulsion explosives sensitized by the chemical sensitizer NaNO2 often encounter incomplete explosion or misfire problems because of the "pressure desensitization" phenomenon, which seriously affects blasting safety and construction progress. A MgH2-sensitized emulsion explosive was invented to solve these problems. Experimental results show that MgH2 can effectively reduce the problem of pressure desensitization. In this paper, the factors which influence the pressure desensitization of two types of emulsion explosives are studied, and resistance to this phenomenon of MgH2-sensitized emulsion explosives is discussed.

  20. Primary explosives

    Energy Technology Data Exchange (ETDEWEB)

    Matyas, Robert; Pachman, Jiri [Pardubice Univ. (Czech Republic). Faculty of Chemical Technology

    2013-06-01

    The first chapter provides background such as the basics of initiation and differences between requirements on primary explosives used in detonators and igniters. The authors then clarify the influence of physical characteristics on explosive properties, focusing on those properties required for primary explosives. Furthermore, the issue of sensitivity is discussed. All the chapters on particular groups of primary explosives are structured in the same way, including introduction, physical and chemical properties, explosive properties, preparation and documented use.

  1. Comparison of the effects in the rock mass of large-scale chemical and nuclear explosions. Final technical report, June 9, 1994--October 9, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Spivak, A.A.

    1995-04-01

    It was found that in the first approximation the mechanical effect of underground nuclear explosion is analogous to the effect of chemical explosion. Really qualitative analysis shows that accompanying mechanical effects of nuclear and chemical explosions are the same: in the both cases explosion consequences are characterized by formation of the camouplet cavity (crater after explosion near free surface), destruction of the rock massif near explosion centre, creation of the stress wave, which forms seismoexplosive effect a long distance from explosion epicentre. Qualitative likeness of underground nuclear explosions and chemical explosions is the base of modelling the mechanical effects of the underground nuclear explosion. In this paper we`ll compare two explosions: nuclear (15-04-84) and chemical (27.06.95) with large power. These explosions were realized at the same geological conditions at Degelen test area, which is a part of the Semipalatinsk Test Site. In the case of the nuclear explosion, the charge was disposed in the face of the deep horizontal gallery. The charge of the chemical explosion was a semisphere from explosives at the rock massif surface. In the both case rock massif behavior after explosions was investigated at underground conditions (in the case of chemical explosion -- in the long underground excavation from explosion epicentre). Mechanical effects from the nuclear and chemical explosions were investigated with the same methods. The changes in geological medium after a large-scale explosive actions will be analyzed in detail too. Investigations of the influence of tectonic energy on the mechanical effects after underground nuclear, explosions represents the main interest. In this paper we`ll discuss this question on the data from underground nuclear explosion, realized 08.09.89 in the deep well at the Balapan test area, at the Semipalatinsk Test Site.

  2. Explosive events in active region observed by IRIS and SST/CRISP

    Science.gov (United States)

    Huang, Z.; Madjarska, M. S.; Scullion, E. M.; Xia, L.-D.; Doyle, J. G.; Ray, T.

    2017-01-01

    Transition-region explosive events (EEs) are characterized by non-Gaussian line profiles with enhanced wings at Doppler velocities of 50-150 km s-1. They are believed to be the signature of solar phenomena that are one of the main contributors to coronal heating. The aim of this study is to investigate the link of EEs to dynamic phenomena in the transition region and chromosphere in an active region. We analyse observations simultaneously taken by the Interface Region Imaging Spectrograph (IRIS) in the Si IV 1394 Å line and the slit-jaw (SJ) 1400 Å images, and the Swedish 1-m Solar Telescope in the Hα line. In total 24 events were found. They are associated with small-scale loop brightenings in SJ 1400 Å images. Only four events show a counterpart in the Hα-35 km s-1 and Hα+35 km s-1 images. Two of them represent brightenings in the conjunction region of several loops that are also related to a bright region (granular lane) in the Hα-35 km s-1 and Hα+35 km s-1 images. 16 are general loop brightenings that do not show any discernible response in the Hα images. Six EEs appear as propagating loop brightenings, from which two are associated with dark jet-like features clearly seen in the Hα-35 km s-1 images. We found that chromospheric events with jet-like appearance seen in the wings of the Hα line can trigger EEs in the transition region and in this case the IRIS Si IV 1394 Å line profiles are seeded with absorption components resulting from Fe II and Ni II. Our study indicates that EEs occurring in active regions have mostly upper-chromosphere/transition-region origin. We suggest that magnetic reconnection resulting from the braidings of small-scale transition region loops is one of the possible mechanisms of energy release that are responsible for the EEs reported in this paper.

  3. The Foggy EUV Corona and Coronal Heating by MHD Waves from Explosive Reconnection Events

    Science.gov (United States)

    Moore, Ron L.; Cirtain, Jonathan W.; Falconer, David A.

    2008-01-01

    In 0.5 arcsec/pixel TRACE coronal EUV images, the corona rooted in active regions that are at the limb and are not flaring is seen to consist of (1) a complex array of discrete loops and plumes embedded in (2) a diffuse ambient component that shows no fine structure and gradually fades with height. For each of two not-flaring active regions, found that the diffuse component is (1) approximately isothermal and hydrostatic and (2) emits well over half of the total EUV luminosity of the active-region corona. Here, from a TRACE Fe XII coronal image of another not-flaring active region, the large sunspot active region AR 10652 when it was at the west limb on 30 July 2004, we separate the diffuse component from the discrete loop component by spatial filtering, and find that the diffuse component has about 60% of the total luminosity. If under much higher spatial resolution than that of TRACE (e. g., the 0.1 arcsec/pixel resolution of the Hi-C sounding-rocket experiment proposed by J. W. Cirtain et al), most of the diffuse component remains diffuse rather being resolved into very narrow loops and plumes, this will raise the possibility that the EUV corona in active regions consists of two basically different but comparably luminous components: one being the set of discrete bright loops and plumes and the other being a truly diffuse component filling the space between the discrete loops and plumes. This dichotomy would imply that there are two different but comparably powerful coronal heating mechanisms operating in active regions, one for the distinct loops and plumes and another for the diffuse component. We present a scenario in which (1) each discrete bright loop or plume is a flux tube that was recently reconnected in a burst of reconnection, and (2) the diffuse component is heated by MHD waves that are generated by these reconnection events and by other fine-scale explosive reconnection events, most of which occur in and below the base of the corona where they are

  4. Explosive and chemical threat detection by surface-enhanced Raman scattering: a review.

    Science.gov (United States)

    Hakonen, Aron; Andersson, Per Ola; Stenbæk Schmidt, Michael; Rindzevicius, Tomas; Käll, Mikael

    2015-09-17

    Acts of terror and warfare threats are challenging tasks for defense agencies around the world and of growing importance to security conscious policy makers and the general public. Explosives and chemical warfare agents are two of the major concerns in this context, as illustrated by the recent Boston Marathon bombing and nerve gas attacks on civilians in the Middle East. To prevent such tragic disasters, security personnel must be able to find, identify and deactivate the threats at multiple locations and levels. This involves major technical and practical challenges, such as detection of ultra-low quantities of hazardous compounds at remote locations for anti-terror purposes and monitoring of environmental sanitation of dumped or left behind toxic substances and explosives. Surface-enhanced Raman scattering (SERS) is one of todays most interesting and rapidly developing methods for label-free ultrasensitive vibrational "fingerprinting" of a variety of molecular compounds. Performance highlights include attomolar detection of TNT and DNT explosives, a sensitivity that few, if any, other technique can compete with. Moreover, instrumentation needed for SERS analysis are becoming progressively better, smaller and cheaper, and can today be acquired for a retail price close to 10,000 US$. This contribution aims to give a comprehensive overview of SERS as a technique for detection of explosives and chemical threats. We discuss the prospects of SERS becoming a major tool for convenient in-situ threat identification and we summarize existing SERS detection methods and substrates with particular focus on ultra-sensitive real-time detection. General concepts, detection capabilities and perspectives are discussed in order to guide potential users of the technique for homeland security and anti-warfare purposes. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Numerical Simulations as Tool to Predict Chemical and Radiological Hazardous Diffusion in Case of Nonconventional Events

    Directory of Open Access Journals (Sweden)

    J.-F. Ciparisse

    2016-01-01

    Full Text Available CFD (Computational Fluid Dynamics simulations are widely used nowadays to predict the behaviour of fluids in pure research and in industrial applications. This approach makes it possible to get quantitatively meaningful results, often in good agreement with the experimental ones. The aim of this paper is to show how CFD calculations can help to understand the time evolution of two possible CBRNe (Chemical-Biological-Radiological-Nuclear-explosive events: (1 hazardous dust mobilization due to the interaction between a jet of air and a metallic powder in case of a LOVA (Loss Of Vacuum Accidents that is one of the possible accidents that can occur in experimental nuclear fusion plants; (2 toxic gas release in atmosphere. The scenario analysed in the paper has consequences similar to those expected in case of a release of dangerous substances (chemical or radioactive in enclosed or open environment during nonconventional events (like accidents or man-made or natural disasters.

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

    Energy Technology Data Exchange (ETDEWEB)

    Chipman, V D

    2011-09-20

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

  7. Multidisciplinary constraints of hydrothermal explosions based on the 2013 Gengissig lake events, Kverkfjöll volcano, Iceland

    Science.gov (United States)

    Montanaro, Cristian; Scheu, Bettina; Gudmundsson, Magnus Tumi; Vogfjörd, Kristín; Reynolds, Hannah Iona; Dürig, Tobias; Strehlow, Karen; Rott, Stefanie; Reuschlé, Thierry; Dingwell, Donald Bruce

    2016-01-01

    Hydrothermal explosions frequently occur in geothermal areas showing various mechanisms and energies of explosivity. Their deposits, though generally hardly recognised or badly preserved, provide important insights to quantify the dynamics and energy of these poorly understood explosive events. Furthermore the host rock lithology of the geothermal system adds a control on the efficiency in the energy release during an explosion. We present results from a detailed study of recent hydrothermal explosion deposits within an active geothermal area at Kverkfjöll, a central volcano at the northern edge of Vatnajökull. On August 15th 2013, a small jökulhlaup occurred when the Gengissig ice-dammed lake drained at Kverkfjöll. The lake level dropped by approximately 30 m, decreasing pressure on the lake bed and triggering several hydrothermal explosions on the 16th. Here, a multidisciplinary approach combining detailed field work, laboratory studies, and models of the energetics of explosions with information on duration and amplitudes of seismic signals, has been used to analyse the mechanisms and characteristics of these hydrothermal explosions. Field and laboratory studies were also carried out to help constrain the sedimentary sequence involved in the event. The explosions lasted for 40-50 s and involved the surficial part of an unconsolidated and hydrothermally altered glacio-lacustrine deposit composed of pyroclasts, lavas, scoriaceous fragments, and fine-grained welded or loosely consolidated aggregates, interbedded with clay-rich levels. Several small fans of ejecta were formed, reaching a distance of 1 km north of the lake and covering an area of approximately 0.3 km2, with a maximum thickness of 40 cm at the crater walls. The material (volume of approximately 104 m3) has been ejected by the expanding boiling fluid, generated by a pressure failure affecting the surficial geothermal reservoir. The maximum thermal, craterisation and ejection energies, calculated

  8. Colorimetric Sensor Arrays for the Detection and Identification of Chemical Weapons and Explosives.

    Science.gov (United States)

    Kangas, Michael J; Burks, Raychelle M; Atwater, Jordyn; Lukowicz, Rachel M; Williams, Pat; Holmes, Andrea E

    2017-03-04

    There is a significant demand for devices that can rapidly detect chemical-biological-explosive (CBE) threats on-site and allow for immediate responders to mitigate spread, risk, and loss. The key to an effective reconnaissance mission is a unified detection technology that analyzes potential threats in real time. In addition to reviewing the current state of the art in the field, this review illustrates the practicality of colorimetric arrays composed of sensors that change colors in the presence of analytes. This review also describes an outlook toward future technologies, and describes how they could possibly be used in areas such as war zones to detect and identify hazardous substances.

  9. Remote chemical biological and explosive agent detection using a robot-based Raman detector

    Science.gov (United States)

    Gardner, Charles W.; Wentworth, Rachel; Treado, Patrick J.; Batavia, Parag; Gilbert, Gary

    2008-04-01

    Current practice for the detection of chemical, biological and explosive (CBE) agent contamination on environmental surfaces requires a human to don protective gear, manually take a sample and then package it for subsequent laboratory analysis. Ground robotics now provides an operator-safe way to make these critical measurements. We describe the development of a robot-deployed surface detection system for CBE agents that does not require the use of antibodies or DNA primers. The detector is based on Raman spectroscopy, a reagentless technique that has the ability to simultaneously identify multiple chemical and biological hazards. Preliminary testing showed the ability to identify CBE simulants in 10 minutes or less. In an operator-blind study, this detector was able to correctly identify the presence of trace explosive on weathered automobile body panels. This detector was successfully integrated on a highly agile robot platform capable of both high speed and rough terrain operation. The detector is mounted to the end of five-axis arm that allows precise interrogation of the environmental surfaces. The robot, arm and Raman detector are JAUS compliant, and are controlled via a radio link from a single operator control unit. Results from the integration testing and from limited field trials are presented.

  10. Odour as a determinant of persistent symptoms after a chemical explosion, a longitudinal study.

    Science.gov (United States)

    Tjalvin, Gro; Magerøy, Nils; Bråtveit, Magne; Lygre, Stein Håkon Låstad; Hollund, Bjørg Eli; Moen, Bente Elisabeth

    2017-04-07

    Foul-smelling environmental pollution was a major concern following a chemical workplace explosion. Malodorous pollution has previously been associated with aggravated physical and psychological health, and in persons affected by a trauma, an incidence-related odour can act as a traumatic reminder. Olfaction may even be of significance in the development and persistence of post-traumatic stress symptoms (PTSS). The present longitudinal study assessed whether perceived smell related to malodorous environmental pollution in the aftermath of the explosion was a determinant of subjective health complaints (SHC) and PTSS among gainfully employed adults, when the malodorous pollution was present, and after pollution clean-up. Questionnaire data from validated instruments were analysed using mixed effects models. Individual odour scores were computed, and the participants (n=486) were divided into high and low odour score groups, respectively. Participants in the high odour score group (n=233) reported more SHC and PTSS than those in the low odour score group (n=253), before and even after the pollution was eliminated. These associations lasted for at least three years after the pollution was removed, and might indicate that prompt clean-up is important to avoid persistent health effects after malodorous chemical spills.

  11. Photo-vibrational sensing of trace chemicals and explosives by long-distance differential laser Doppler vibrometer

    Science.gov (United States)

    Fu, Yu; Liu, Huan; Hu, Qi; Xie, Jiecheng

    2017-05-01

    Photoacoustic/photothermal spectroscopy is an established technique for trace detection of chemicals and explosives. Normally high-sensitive microphone or PZT sensor is used to detect the signal in photoacoustic cell. In recent years, laser Doppler vibrometer (LDV) is proposed to remote-sense photoacoustic signal on various substrates. It is a highsensitivity sensor with a displacement resolution of laser (QCL) at their absorbance peak. A home-developed differential LDV at 1550nm wavelength is applied to detect the vibration signal at 100m. A differential configuration is applied to minimize the environment factors, such as environment noise and vibration, air turbulence, etc. and increase the detection sensitivity. The photo-vibrational signal of chemicals and explosives on different substrates are detected. The results show the potential of the proposed technique on detection of trace chemicals and explosives at long standoff distance.

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

    Science.gov (United States)

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

    2014-12-01

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

  13. Incorporating Love- and Rayleigh-wave magnitudes, unequal earthquake and explosion variance assumptions and interstation complexity for improved event screening

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Dale N [Los Alamos National Laboratory; Bonner, Jessie L [WESTON GEOPHYSICAL; Stroujkova, Anastasia [WESTON GEOPHYSICAL; Shumway, Robert [UC/DAVIS; Russell, David R [AFTAC

    2009-01-01

    Our objective is to improve seismic event screening using the properties of surface waves, We are accomplishing this through (1) the development of a Love-wave magnitude formula that is complementary to the Russell (2006) formula for Rayleigh waves and (2) quantifying differences in complexities and magnitude variances for earthquake and explosion-generated surface waves. We have applied the M{sub s} (VMAX) analysis (Bonner et al., 2006) using both Love and Rayleigh waves to events in the Middle East and Korean Peninsula, For the Middle East dataset consisting of approximately 100 events, the Love M{sub s} (VMAX) is greater than the Rayleigh M{sub s} (VMAX) estimated for individual stations for the majority of the events and azimuths, with the exception of the measurements for the smaller events from European stations to the northeast. It is unclear whether these smaller events suffer from magnitude bias for the Love waves or whether the paths, which include the Caspian and Mediterranean, have variable attenuation for Love and Rayleigh waves. For the Korean Peninsula, we have estimated Rayleigh- and Love-wave magnitudes for 31 earthquakes and two nuclear explosions, including the 25 May 2009 event. For 25 of the earthquakes, the network-averaged Love-wave magnitude is larger than the Rayleigh-wave estimate. For the 2009 nuclear explosion, the Love-wave M{sub s} (VMAX) was 3.1 while the Rayleigh-wave magnitude was 3.6. We are also utilizing the potential of observed variances in M{sub s} estimates that differ significantly in earthquake and explosion populations. We have considered two possible methods for incorporating unequal variances into the discrimination problem and compared the performance of various approaches on a population of 73 western United States earthquakes and 131 Nevada Test Site explosions. The approach proposes replacing the M{sub s} component by M{sub s} + a* {sigma}, where {sigma} denotes the interstation standard deviation obtained from the

  14. Predicting Heats of Explosion of Nitroaromatic Compounds through NBO Charges and 15N NMR Chemical Shifts of Nitro Groups

    Directory of Open Access Journals (Sweden)

    Ricardo Infante-Castillo

    2012-01-01

    Full Text Available This work presents a new quantitative model to predict the heat of explosion of nitroaromatic compounds using the natural bond orbital (NBO charge and 15N NMR chemical shifts of the nitro groups (15NNitro as structural parameters. The values of the heat of explosion predicted for 21 nitroaromatic compounds using the model described here were compared with experimental data. The prediction ability of the model was assessed by the leave-one-out cross-validation method. The cross-validation results show that the model is significant and stable and that the predicted accuracy is within 0.146 MJ kg−1, with an overall root mean squared error of prediction (RMSEP below 0.183 MJ kg−1. Strong correlations were observed between the heat of explosion and the charges (R2 = 0.9533 and 15N NMR chemical shifts (R2 = 0.9531 of the studied compounds. In addition, the dependence of the heat of explosion on the presence of activating or deactivating groups of nitroaromatic explosives was analyzed. All calculations, including optimizations, NBO charges, and 15NNitro NMR chemical shifts analyses, were performed using density functional theory (DFT and a 6-311+G(2d,p basis set. Based on these results, this practical quantitative model can be used as a tool in the design and development of highly energetic materials (HEM based on nitroaromatic compounds.

  15. Explosive and chemical threat detection by surface-enhanced Raman scattering: A review

    DEFF Research Database (Denmark)

    Hakonen, Aron; Andersson, Per Ola; Schmidt, Michael Stenbæk

    2015-01-01

    Acts of terror and warfare threats are challenging tasks for defense agencies around the world and of growing importance to security conscious policy makers and the general public. Explosives and chemical warfare agents are two of the major concerns in this context, as illustrated by the recent...... Boston Marathon bombing and nerve gas attacks on civilians in the Middle East. To prevent such tragic disasters, security personnel must be able to find, identify and deactivate the threats at multiple locations and levels. This involves major technical and practical challenges, such as detection......-situ threat identification and we summarize existing SERS detection methods and substrates with particular focus on ultra-sensitive real-time detection. General concepts, detection capabilities and perspectives are discussed in order to guide potential users of the technique for homeland security and anti...

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

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Audrey Noreen [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2006-01-01

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

  17. EPA and DuPont Reach Major Settlement After Fatal Chemical Explosion in Tonawanda, N.Y.

    Science.gov (United States)

    (New York, N.Y.) The U.S. Environmental Protection Agency announced that E.I. du Pont de Nemours & Co. (DuPont) has agreed to pay a fine of $724,000 in settlement of Clean Air Act violations relating to a fire and explosion at its chemical plant in Ton

  18. The Nose Knows: Developing Advanced Chemical Sensors for the Remote Detection of Improvised Explosive Devices in 2030

    Science.gov (United States)

    2009-04-01

    insect algorithms into a reliable artificial intelligence will permit minimal human controller input. 58 In nature, pheromones are chemical...developing bio-chemical sensing and urban operations will translate into tangible gains with explosive sensing. Converting insect behaviors into... pheromones ” similar to the way that ants mark their territory, a UAV can detect how much of an individual terrain has been covered by itself and

  19. Nonlinear Methodologies for Identifying Seismic Event and Nuclear Explosion Using Random Forest, Support Vector Machine, and Naive Bayes Classification

    Directory of Open Access Journals (Sweden)

    Longjun Dong

    2014-01-01

    Full Text Available The discrimination of seismic event and nuclear explosion is a complex and nonlinear system. The nonlinear methodologies including Random Forests (RF, Support Vector Machines (SVM, and Naïve Bayes Classifier (NBC were applied to discriminant seismic events. Twenty earthquakes and twenty-seven explosions with nine ratios of the energies contained within predetermined “velocity windows” and calculated distance are used in discriminators. Based on the one out cross-validation, ROC curve, calculated accuracy of training and test samples, and discriminating performances of RF, SVM, and NBC were discussed and compared. The result of RF method clearly shows the best predictive power with a maximum area of 0.975 under the ROC among RF, SVM, and NBC. The discriminant accuracies of RF, SVM, and NBC for test samples are 92.86%, 85.71%, and 92.86%, respectively. It has been demonstrated that the presented RF model can not only identify seismic event automatically with high accuracy, but also can sort the discriminant indicators according to calculated values of weights.

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

    Science.gov (United States)

    Hohil, Myron E.; Desai, Sachi

    2005-10-01

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

  1. NMIS With Gamma Spectrometry for Attributes of Pu and HEU, Explosives and Chemical Agents

    Energy Technology Data Exchange (ETDEWEB)

    Mihalczo, J. T.; Mattingly, J. K.; Mullens, J. A.; Neal, J. S.

    2002-05-10

    The concept for the system described herein is an active/passive Nuclear Materials Identification System{sup 2} (NMIS) that incorporates gamma ray spectrometry{sup 3}. This incorporation of gamma ray spectrometry would add existing capability into this system. This Multiple Attribute System can determine a wide variety of attributes for Pu and highly enriched uranium (HEU) of which a selected subset could be chosen. This system can be built using commercial off the shelf (COTS) components. NMIS systems are at All-Russian Scientific Research Institute of Experimental Physics (VNIIEF) and Russian Federal Nuclear Center Institute of Technical Physics, (VNIITF) and measurements with Pu have been performed at VNIIEF and analyzed successfully for mass and thickness of Pu. NMIS systems are being used successfully for HEU at the Y-12 National Security Complex. The use of active gamma ray spectrometry for high explosive HE and chemical agent detection is a well known activation analysis technique, and it is incorporated here. This report describes the system, explains the attribute determination methods for fissile materials, discusses technical issues to be resolved, discusses additional development needs, presents a schedule for building from COTS components, and assembly with existing components, and discusses implementation issues such as lack of need for facility modification and low radiation exposure.

  2. The 2010 explosive eruption of Java's Merapi volcano—A ‘100-year’ event

    Science.gov (United States)

    Surono,; Jousset, Philippe; Pallister, John S.; Boichu, Marie; Buongiorno, M. Fabrizia; Budisantoso, Agus; Costa, Fidel; Andreastuti, Supriyati; Prata, Fred; Schneider, David; Clarisse, Lieven; Humaida, Hanik; Sumarti, Sri; Bignami, Christian; Griswold, Julia P.; Carn, Simon A.; Oppenheimer, Clive; Lavigne, Franck

    2012-01-01

    Merapi volcano (Indonesia) is one of the most active and hazardous volcanoes in the world. It is known for frequent small to moderate eruptions, pyroclastic flows produced by lava dome collapse, and the large population settled on and around the flanks of the volcano that is at risk. Its usual behavior for the last decades abruptly changed in late October and early November 2010, when the volcano produced its largest and most explosive eruptions in more than a century, displacing at least a third of a million people, and claiming nearly 400 lives. Despite the challenges involved in forecasting this ‘hundred year eruption’, we show that the magnitude of precursory signals (seismicity, ground deformation, gas emissions) was proportional to the large size and intensity of the eruption. In addition and for the first time, near-real-time satellite radar imagery played an equal role with seismic, geodetic, and gas observations in monitoring eruptive activity during a major volcanic crisis. The Indonesian Center of Volcanology and Geological Hazard Mitigation (CVGHM) issued timely forecasts of the magnitude of the eruption phases, saving 10,000–20,000 lives. In addition to reporting on aspects of the crisis management, we report the first synthesis of scientific observations of the eruption. Our monitoring and petrologic data show that the 2010 eruption was fed by rapid ascent of magma from depths ranging from 5 to 30 km. Magma reached the surface with variable gas content resulting in alternating explosive and rapid effusive eruptions, and released a total of ~ 0.44 Tg of SO2. The eruptive behavior seems also related to the seismicity along a tectonic fault more than 40 km from the volcano, highlighting both the complex stress pattern of the Merapi region of Java and the role of magmatic pressurization in activating regional faults. We suggest a dynamic triggering of the main explosions on 3 and 4 November by the passing seismic waves generated by regional

  3. School Siting Near Industrial Chemical Facilities: Findings from the U.S. Chemical Safety Board?s Investigation of the West Fertilizer Explosion

    OpenAIRE

    Tinney, Veronica A.; Denton, Jerad M.; Sciallo-Tyler, Lucy; Paulson, Jerome A.

    2016-01-01

    Background: The U.S. Chemical Safety and Hazard Investigation Board (CSB) investigated the 17 April 2013 explosion at the West Fertilizer Company (WFC) that resulted in 15 fatalities, more than 260 injuries, and damage to more than 150 buildings. Among these structures were four nearby school buildings cumulatively housing children in grades kindergarten?12, a nursing care facility, and an apartment complex. The incident occurred during the evening when school was not in session, which reduce...

  4. Coupled phase transformation, chemical decomposition, and deformation in plastic-bonded explosive: Models

    Science.gov (United States)

    Levitas, Valery I.; Henson, Bryan F.; Smilowitz, Laura B.; Zerkle, David K.; Asay, Blaine W.

    2007-12-01

    A continuum thermomechanochemical model of the behavior of a plastic-bonded explosive (PBX) 9501 formulation consisting of the energetic crystal octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) embedded in a polymeric binder is developed. Our main focus is on the study of the β ↔δ phase transformations (PTs) in crystalline HMX under a complex pressure-temperature path. To reproduce the pressure-temperature path, in particular during heating of PBX inside of a rigid cylinder, the β ↔δ PTs in HMX are coupled to chemical decomposition of the HMX and binder leading to gas formation, gas leaking from the cylinder, elastic, thermal, and transformational straining as well as straining due to mass loss. A fully physically based thermodynamic and kinetic model of the β ↔δ PT in HMX crystal is developed. It is based on a suggested nucleation mechanism via melt mediated nanocluster transformation and the recently revealed growth mechanism via internal stress-induced virtual melting. During the nucleation, nanosize clusters of the β phase dissolve in a molten binder and transform diffusionally into δ phase clusters. During the interface propagation, internal stresses induced by transformation strain cause the melting of the stressed δ phase much below (120 K) the melting temperature and its immediate resolidification into the unstressed δ phase. These mechanisms explain numerous puzzles of HMX polymorphism and result in overall transformation kinetics that is in good agreement with experiments. Simple phenomenological equations for kinetics of chemical decomposition of the HMX and the binder are in good correspondence with experiments as well. A continuum deformation model is developed in two steps. The geometrically linear (small strain) theory is used to prove that the internal stresses and macroscopic shear stresses are negligible. Then a large strain theory is developed under hydrostatic loading. The developed continuum thermomechanochemical model is

  5. Estimation Source Parameters of Large-Scale Chemical Surface Explosions and Recent Underground Nuclear Tests

    Science.gov (United States)

    Gitterman, Y.; Kim, S.; Hofstetter, R.

    2013-12-01

    Large-scale surface explosions were conducted by the Geophysical Institute of Israel at Sayarim Military Range (SMR), Negev desert: 82 tons of strong HE explosives in August 2009, and 10&100 tons of ANFO explosives in January 2011. The main goal was to provide strong controlled sources in different wind conditions, for calibration of IMS infrasound stations. Numerous dense observations of blast waves were provided by high-pressure, acoustic and seismic sensors at near-source ( 2000 tons) ANFO surface shots at White Sands Military Range (WSMR) were analyzed for SS time delay. The Secondary Shocks were revealed on the records in the range 1.5-60 km and showed consistency with the SMR data, thus extending the charge and distance range for the developed SS delay relationship. Obtained results suggest that measured SS delays can provide important information about an explosion source character, and can be used as a new simple cost-effective yield estimator for explosions with known type of explosives. The new results are compared with analogous available data of surface nuclear explosions. Special distinctions in air-blast waves are revealed and analyzed, resulting from the different source phenomenology (energy release). Two underground nuclear explosions conducted by North Korea in 2009 and 2013 were recorded by several stations of Israel Seismic Network. Pronounced minima (spectral nulls) at 1.2-1.3 Hz were revealed in the spectra of teleseismic P-waves. For a ground-truth explosion with a shallow source depth (relatively to an earthquake), this phenomenon can be interpreted in terms of the interference between the down-going P-wave energy and the pP phase reflected from the Earth's surface. A similar effect was observed before at ISN stations for the Pakistan explosion (28.05.98) at a different frequency 1.7 Hz indicating the source- and not site-effect. Based on the null frequency dependency on the near-surface acoustic velocity and the source depth, the depth of

  6. School Siting Near Industrial Chemical Facilities: Findings from the U.S. Chemical Safety Board's Investigation of the West Fertilizer Explosion.

    Science.gov (United States)

    Tinney, Veronica A; Denton, Jerad M; Sciallo-Tyler, Lucy; Paulson, Jerome A

    2016-10-01

    The U.S. Chemical Safety and Hazard Investigation Board (CSB) investigated the 17 April 2013 explosion at the West Fertilizer Company (WFC) that resulted in 15 fatalities, more than 260 injuries, and damage to more than 150 buildings. Among these structures were four nearby school buildings cumulatively housing children in grades kindergarten-12, a nursing care facility, and an apartment complex. The incident occurred during the evening when school was not in session, which reduced the number of injuries. The goal of this commentary is to illustrate the consequences of siting schools near facilities that store or use hazardous chemicals, and highlight the need for additional regulations to prevent future siting of schools near these facilities. We summarize the findings of the CSB's investigation related to the damaged school buildings and the lack of regulation surrounding the siting of schools near facilities that store hazardous chemicals. In light of the current lack of federal authority for oversight of land use near educational institutions, state and local governments should take a proactive role in promulgating state regulations that prohibit the siting of public receptors, such as buildings occupied by children, near facilities that store hazardous chemicals. Tinney VA, Denton JM, Sciallo-Tyler L, Paulson JA. 2016. School siting near industrial chemical facilities: findings from the U.S. Chemical Safety Board's investigation of the West Fertilizer Explosion. Environ Health Perspect 124:1493-1496; http://dx.doi.org/10.1289/EHP132.

  7. Multi-wavelength Observations of Two Explosive Events and Their Effects on the Solar Atmosphere

    Directory of Open Access Journals (Sweden)

    Agustinus G. Admiranto

    2016-09-01

    Full Text Available We investigated two flares in the solar atmosphere that occurred on June 3, 2012 and July 6, 2012 and caused propagation of Moreton and EIT waves. In the June 3 event, we noticed a filament winking which presumably was caused by the wave propagation from the flare. An interesting feature of this event is that there was a reflection of this wave by a coronal hole located alongside the wave propagation, but not all of this wave was transmitted by the coronal hole. Using the running difference method, we calculated the speed of Moreton and EIT waves and we found values of 926 km/s before the reflection and 276 km/s after the reflection (Moreton wave and 1,127 km/s before the reflection and 46 km/s after the reflection (EIT wave. In the July 6 event, this phenomenon was accompanied by type II and type III solar radio bursts, and we also performed a running difference analysis to find the speed of the Moreton wave, obtaining a value of 988 km/s. The speed derived from the analysis of the solar radio burst was 1,200 km/s, and we assume that this difference was caused by the different nature of the motions in these phenomena, where the solar radio burst was caused by the propagating particles, not waves.

  8. Chemical and physical modification of hemp fibres by steam explosion technology

    Science.gov (United States)

    Sutka, Anna; Kukle, Silvija; Gravitis, Janis; Berzins, Agris

    2013-12-01

    In current research attempt has been made to analyse hemp fibres treated with steam explosion (SE) technology. Disintegration of hemp fibres separated from non-retted, dew-retted and dried stems of hemp ('Purini')[1] by alkali treatment and steam explosion (SE) were investigated. An average intensive SE in combination with the hydro-thermal and alkali after-treatment allows decreasing the diameter of hemp fibres and reduce the concentration of non-celluloses components, among them hemicelluloses, lignin, pectin, waxes and water [1;2].

  9. Safety in the Chemical Laboratory: Group Contribution Method for Predicting the Potential of a Chemical Composition to Cause an Explosion.

    Science.gov (United States)

    Seaton, William H.

    1989-01-01

    Provided is an empirical method to train students to avoid physical disaster in their work experience. Discussed is a computer program, CHETAH, which can be used in advance of synthesis to classify the possible explosive nature of the products. Plosophoric and auxoplosive weights of many organic groups are listed. (MVL)

  10. A Comparison of Neutron-Based Non-Destructive Assessment Methods for Chemical Warfare Materiel and High Explosives

    Energy Technology Data Exchange (ETDEWEB)

    E.H. Seabury; D.L. Chichester; C.J. Wharton; A.J. Caffrey

    2008-08-01

    Prompt Gamma Neutron Activation Analysis (PGNAA) systems employ neutrons as a probe to interrogate items, e.g. chemical warfare materiel-filled munitions. The choice of a neutron source in field-portable systems is determined by its ability to excite nuclei of interest, operational concerns such as radiological safety and ease-of-use, and cost. Idaho National Laboratory’s PINS Chemical Assay System has traditionally used a Cf-252 isotopic neutron source, but recently a Deuterium-Tritium (DT) Electronic Neutron Generator (ENG) has been tested as an alternate neutron source. This paper presents the results of using both of these neutron sources to interrogate chemical warfare materiel (CWM) and high explosive (HE) filled munitions.

  11. Calorimetric studies and lessons on fires and explosions of a chemical plant producing CHP and DCPO

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Jing-Ming; Su, Mao-Sheng; Huang, Chiao-Ying [Department of Occupational Safety and Health, Chia Nan University of Pharmacy and Science, Tainan, Taiwan, ROC (China); Duh, Yih-Shing, E-mail: yihshingduh@yahoo.com.tw [Department of Safety, Health and Environmental Engineering, National United University, No. 1 Lien-Da, Miaoli, Taiwan, ROC (China)

    2012-05-30

    Highlights: Black-Right-Pointing-Pointer We analyzed fire and explosion incidents in a plant producing CHP and DCPO. Black-Right-Pointing-Pointer Data from calorimeters reveal causes and phenomena associated with the incidents. Black-Right-Pointing-Pointer The credible worst scenario was thermal explosion. Black-Right-Pointing-Pointer Incidents may be avoided by implementing DIERS methodology. - Abstract: Cumene hydroperoxide (CHP) has been used in producing phenol, dicumyl peroxide (DCPO) and as an initiator for synthesizing acrylonitrile-butadiene-styrene (ABS) resin by copolymerization in Taiwan. Four incidents of fire and explosion induced by thermal runaway reactions were occurred in a same plant producing CHP, DCPO and bis-(tert-butylperoxy isopropyl) benzene peroxide (BIBP). The fourth fire and explosion occurred in the CHP reactor that resulted in a catastrophic damage in reaction region and even spread throughout storage area. Descriptions on the occurrences of these incidents were assessed by the features of processes, reaction schemes and unexpected side reactions. Calorimetric data on thermokinetics and pressure were used for explaining the practical consequences or which the worst cases encountered in this kind of plant. Acceptable risk associated with emergency relief system design is vital for a plant producing organic peroxide. These basic data for designing an inherently safer plant can be conducted from adiabatic calorimetry. An encouraging deduction has been drawn here, these incidents may be avoided by the implementation of API RP 520, API RP 521, DIERS technology, OSHA 1910.119 and AIChE's CCPS recommended PSM elements.

  12. Polymeric binder for explosives

    Science.gov (United States)

    Bissell, E. R.

    1972-01-01

    Chemical reaction for producing a polymer which can be mixed with explosives to produce a rigid material is discussed. Physical and chemical properties of polymers are described and chemical structure of the polymer is illustrated.

  13. Laser based in-situ and standoff detection of chemical warfare agents and explosives

    Science.gov (United States)

    Patel, C. Kumar N.

    2009-09-01

    Laser based detection of gaseous, liquid and solid residues and trace amounts has been developed ever since lasers were invented. However, the lack of availability of reasonably high power tunable lasers in the spectral regions where the relevant targets can be interrogated as well as appropriate techniques for high sensitivity, high selectivity detection has hampered the practical exploitation of techniques for the detection of targets important for homeland security and defense applications. Furthermore, emphasis has been on selectivity without particular attention being paid to the impact of interfering species on the quality of detection. Having high sensitivity is necessary but not a sufficient condition. High sensitivity assures a high probability of detection of the target species. However, it is only recently that the sensor community has come to recognize that any measure of probability of detection must be associated with a probability of false alarm, if it is to have any value as a measure of performance. This is especially true when one attempts to compare performance characteristics of different sensors based on different physical principles. In this paper, I will provide a methodology for characterizing the performance of sensors utilizing optical absorption measurement techniques. However, the underlying principles are equally application to all other sensors. While most of the current progress in high sensitivity, high selectivity detection of CWAs, TICs and explosives involve identifying and quantifying the target species in-situ, there is an urgent need for standoff detection of explosives from safe distances. I will describe our results on CO2 and quantum cascade laser (QCL) based photoacoustic sensors for the detection of CWAs, TICs and explosives as well the very new results on stand-off detection of explosives at distances up to 150 meters. The latter results are critically important for assuring safety of military personnel in battlefield

  14. Explosive nucleosynthesis in tidal disruption events of massive white dwarfs, and their debris

    Science.gov (United States)

    Tanikawa, Ataru; Sato, Yushi; Nomoto, Ken'Ichi; Maeda, Keiichi; Nakasato, Naohito; Hachisu, Izumi

    We perform SPH simulations coupled with nuclear reactions to follow tidal disruption events (TDEs) of white dwarfs (WDs) by intermediate mass black holes (IMBHs). We consider an oxygen-neon-magnesium (ONeMg) WD with 1.2M ⊙ as well as a helium (He) WD with 0.3M ⊙, and a carbon-oxygen (CO) WD with 0.6M ⊙. Our WD models have different numbers of SPH particles, N, up to a few 10 million. We find that nucleosynthesis does not converge against N even for N > 107. For all the WDs, the amount of radioactive nuclei, such as 56Ni, decreases with increasing N. Nuclear reactions might be extinguished for infinitely large N. Our results show that these kinds of TDEs, if solely powered by radioactive decays, are much dimmer optical transients similar to Type Ia supernovae as previously suggested.

  15. School Siting Near Industrial Chemical Facilities: Findings from the U.S. Chemical Safety Board’s Investigation of the West Fertilizer Explosion

    Science.gov (United States)

    Tinney, Veronica A.; Denton, Jerad M.; Sciallo-Tyler, Lucy; Paulson, Jerome A.

    2016-01-01

    Background: The U.S. Chemical Safety and Hazard Investigation Board (CSB) investigated the 17 April 2013 explosion at the West Fertilizer Company (WFC) that resulted in 15 fatalities, more than 260 injuries, and damage to more than 150 buildings. Among these structures were four nearby school buildings cumulatively housing children in grades kindergarten–12, a nursing care facility, and an apartment complex. The incident occurred during the evening when school was not in session, which reduced the number of injuries. Objectives: The goal of this commentary is to illustrate the consequences of siting schools near facilities that store or use hazardous chemicals, and highlight the need for additional regulations to prevent future siting of schools near these facilities. Discussion: We summarize the findings of the CSB’s investigation related to the damaged school buildings and the lack of regulation surrounding the siting of schools near facilities that store hazardous chemicals. Conclusions: In light of the current lack of federal authority for oversight of land use near educational institutions, state and local governments should take a proactive role in promulgating state regulations that prohibit the siting of public receptors, such as buildings occupied by children, near facilities that store hazardous chemicals. Citation: Tinney VA, Denton JM, Sciallo-Tyler L, Paulson JA. 2016. School siting near industrial chemical facilities: findings from the U.S. Chemical Safety Board’s investigation of the West Fertilizer Explosion. Environ Health Perspect 124:1493–1496; http://dx.doi.org/10.1289/EHP132 PMID:27483496

  16. 6 ka anoxic condition in the Sibuyan Sea Basin, Philippines - possible link with an explosive eruption event?

    Science.gov (United States)

    Catane, S. G.; Fernando, A.; Peleo-Alampay, A.; Tejada, M. G.

    2010-12-01

    Marine tephra layers in Philippine inland seas were studied to evaluate the history of explosive volcanism in the region and their impact on the marine environment. Two discrete andesitic (SiO*blc*2*elc* = 55-63 wt%) tephra layers were found at depths 446.5-448.4 cm and 454.9-455.8 cm in the gravity core MD 3057 recovered during the Marion Dufresne Marco Polo 2 cruise in 2006. The 7m-long core was retrieved from the northern portion of the Sibuyan Sea Basin at 1660 m below sea level. A C-14 age of 6 ka was obtained for the lower tephra using benthic foraminifera collected immediately below the tephra layer. The tephra layers have similar major element compositions and follow the same fractionation trend on the basis of glass geochemistry. Compositions are distinct from the nearby active andesitic volcanoes, Taal and Mayon. Microprobe imaging showed the occurrence of authigenic pyrite within the lower andesitic tephra layer. Pyrite occurs as euhedral crystals or granular masses (framboids), which are isolated particles or foraminiferal infillings. Framboidal pyrite is associated with anoxic environments where anaerobic bacteria reduces SO*blc*4*elc* dissolved in sea water, initiating the formation of H*blc*2*elc*S. H2S reacts with iron in sediments to form pyrite. Anoxic conditions occur in ocean basins with restricted water exchange due to a physical barrier (sill), density stratification or where input of organic material is high. Alternatively, anoxic conditions may have been caused by the death of benthic organisms due to tephra deposition by depriving the organisms of their food supply. The effect of this apparent anoxic event on benthic foraminifera will be analyzed in detail. It is postulated that these anoxic conditions may cause a decline in the benthic foraminifera occurrence. The extent and duration of anoxic condition of the northern part of the Sibuyan Sea Basin 6 ka needs to be clarified because present-day water condition in the basin is normal. If

  17. Reliable Classification of High Explosive and Chemical/Biological Artillery Using Acoustic Sensors

    National Research Council Canada - National Science Library

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

    2006-01-01

    .... In contrast, the current detection of chemical/biological (CB) agents expelled into a battlefield environment is limited to the response of chemical sensors that must be located within close proximity to the CB agent...

  18. Strengthening Hospital Surge Capacity in the Event of Explosive or Chemical Terrorist Attacks

    Science.gov (United States)

    2009-03-01

    Orthopedics 8 1.95% Emergency Medicine 7 1.70% Ear, Nose, and Throat 7 1.70% Urology 5 1.22% Dental 5 1.22% Neurology 4 0.97% Podiatry 1 0.24...1.15% Ear, Nose, and Throat 2 1.15% Ophthalmology 1 0.57% Podiatry 1 0.57% Plastic Surgery 1 0.57% Table 2. Disciplines of Attending...obstetrics-gynecology, ophthalmology, podiatry , plastics, orthopedics, urology, ear-nose-throat, and dentistry. A total of 293 respondents are identified

  19. Identification of Groundwater Nitrate Contamination from Explosives Used in Road Construction: Isotopic, Chemical, and Hydrologic Evidence.

    Science.gov (United States)

    Degnan, James R; Böhlke, J K; Pelham, Krystle; Langlais, David M; Walsh, Gregory J

    2016-01-19

    Explosives used in construction have been implicated as sources of NO3(-) contamination in groundwater, but direct forensic evidence is limited. Identification of blasting-related NO3(-) can be complicated by other NO3(-) sources, including agriculture and wastewater disposal, and by hydrogeologic factors affecting NO3(-) transport and stability. Here we describe a study that used hydrogeology, chemistry, stable isotopes, and mass balance calculations to evaluate groundwater NO3(-) sources and transport in areas surrounding a highway construction site with documented blasting in New Hampshire. Results indicate various groundwater responses to contamination: (1) rapid breakthrough and flushing of synthetic NO3(-) (low δ(15)N, high δ(18)O) from dissolution of unexploded NH4NO3 blasting agents in oxic groundwater; (2) delayed and reduced breakthrough of synthetic NO3(-) subjected to partial denitrification (high δ(15)N, high δ(18)O); (3) relatively persistent concentrations of blasting-related biogenic NO3(-) derived from nitrification of NH4(+) (low δ(15)N, low δ(18)O); and (4) stable but spatially variable biogenic NO3(-) concentrations, consistent with recharge from septic systems (high δ(15)N, low δ(18)O), variably affected by denitrification. Source characteristics of denitrified samples were reconstructed from dissolved-gas data (Ar, N2) and isotopic fractionation trends associated with denitrification (Δδ(15)N/Δδ(18)O ≈ 1.31). Methods and data from this study are expected to be applicable in studies of other aquifers affected by explosives used in construction.

  20. Calorimetric studies and lessons on fires and explosions of a chemical plant producing CHP and DCPO.

    Science.gov (United States)

    Hsu, Jing-Ming; Su, Mao-Sheng; Huang, Chiao-Ying; Duh, Yih-Shing

    2012-05-30

    Cumene hydroperoxide (CHP) has been used in producing phenol, dicumyl peroxide (DCPO) and as an initiator for synthesizing acrylonitrile-butadiene-styrene (ABS) resin by copolymerization in Taiwan. Four incidents of fire and explosion induced by thermal runaway reactions were occurred in a same plant producing CHP, DCPO and bis-(tert-butylperoxy isopropyl) benzene peroxide (BIBP). The fourth fire and explosion occurred in the CHP reactor that resulted in a catastrophic damage in reaction region and even spread throughout storage area. Descriptions on the occurrences of these incidents were assessed by the features of processes, reaction schemes and unexpected side reactions. Calorimetric data on thermokinetics and pressure were used for explaining the practical consequences or which the worst cases encountered in this kind of plant. Acceptable risk associated with emergency relief system design is vital for a plant producing organic peroxide. These basic data for designing an inherently safer plant can be conducted from adiabatic calorimetry. An encouraging deduction has been drawn here, these incidents may be avoided by the implementation of API RP 520, API RP 521, DIERS technology, OSHA 1910.119 and AIChE's CCPS recommended PSM elements. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  1. Acute effects of pre-event lower limb massage on explosive and high speed motor capacities and flexibility.

    Science.gov (United States)

    Arabaci, Ramiz

    2008-01-01

    The aim of this study was to examine the acute effects of pre- performance lower limb massage after warm-up on explosive and high-speed motor capacities and flexibility. Twenty-four physically active healthy Caucasian male subjects volunteered to participate in this study. All subjects were from a Physical Education and Sport Department in a large university in Turkey. The study had a counterbalanced crossover design. Each of the subjects applied the following intervention protocols in a randomised order; (a) massage, (b) stretching, and (c) rest. Before (pre) and after (post) each of the interventions, the 10 meter acceleration (AS), flying start 20 meter sprint (FS), 30 meter sprint from standing position (TS), leg reaction time (LR), vertical jump (VJ) and sit & reach (SR) tests were performed. A Wilcoxon's signed rank test was used to compare before and after test values within the three interventions (massage, stretching and rest). The data showed a significant worsening, after massage and stretching interventions, in the VJ, LR (only in stretching intervention), AS and TS tests (p performance (p performing 10 minute posterior and 5 minute anterior lower limb Swedish massage has an adverse effect on vertical jump, speed, and reaction time, and a positive effect on sit and reach test results. Key pointsPerforming 10 minute posterior and 5 minute anterior lower limb Swedish massages has an adverse affect on vertical jump, speed, and reaction time and a positive effect on sit and reach test results.According to the present results, long duration massage should not be recommended for warm-ups.Larger subject pools are needed to verify these events.

  2. Demonstrated Wavelength Portability of Raman Reference Data for Explosives and Chemical Detection

    Directory of Open Access Journals (Sweden)

    Timothy J. Johnson

    2012-01-01

    Full Text Available As Raman spectroscopy continues to evolve, questions arise as to the portability of Raman data: dispersive versus Fourier transform, wavelength calibration, intensity calibration, and in particular the frequency of the excitation laser. While concerns about fluorescence arise in the visible or ultraviolet, most modern (portable systems use near-infrared excitation lasers, and many of these are relatively close in wavelength. We have investigated the possibility of porting reference data sets from one NIR wavelength system to another: We have constructed a reference library consisting of 145 spectra, including 20 explosives, as well as sundry other compounds and materials using a 1064 nm spectrometer. These data were used as a reference library to evaluate the same 145 compounds whose experimental spectra were recorded using a second 785 nm spectrometer. In 128 cases of 145 (or 88.3% including 20/20 for the explosives, the compounds were correctly identified with a mean “hit score” of 954 of 1000. Adding in criteria for when to declare a correct match versus when to declare uncertainty, the approach was able to correctly categorize 134 out of 145 spectra, giving a 92.4% accuracy. For the few that were incorrectly identified, either the matched spectra were spectroscopically similar to the target or the 785 nm signal was degraded due to fluorescence. The results indicate that imported data recorded at a different NIR wavelength can be successfully used as reference libraries, but key issues must be addressed: the reference data must be of equal or higher resolution than the resolution of the current sensor, the systems require rigorous wavelength calibration, and wavelength-dependent intensity response should be accounted for in the different systems.

  3. Physical and chemical evidence remaining after the explosion of large improvised bombs. Part 1: firings of ammonium nitrate/sugar and urea nitrate.

    Science.gov (United States)

    Phillips, S A; Lowe, A; Marshall, M; Hubbard, P; Burmeister, S G; Williams, D R

    2000-03-01

    Recent criminal acts in the United Kingdom, United States and other countries have demonstrated the dangers to public safety from the criminal use of improvised explosives on a large scale. Four sets of trials were carried out over four years, partly in collaboration with the United States Federal Bureau of Investigation, involving the firing of large bombs, mostly fertilizer based. The principal objectives of the firings were to measure the physical effects of the explosions upon objects representative of those that would be found at a real bomb scene and to recover any chemical traces deposited on these objects. The results are intended for use as an aid in determining the approximate size and type of an explosive employed in a terrorist attack. This paper describes the background behind the trials, the procedures for preparation of witness materials and charges, and the collection and analysis of physical and chemical evidence.

  4. Establishment of a Center for Development of Chemical Sensors for Explosives at University of Puerto Rico-Mayaguez

    Science.gov (United States)

    2011-02-08

    1345. 61. Luna-Pineda, T., Gonzalez, L., Mendez, J., Cabanzo-Olarte, A.C., Rizo- Vivas , O.L., Hernandez-Rivera, S.P, Mina, N. and Castro-Rosario, M.E...of explosives; published chapter on state of art of vibrational spectroscopy standoff detection of explosives.  Started experiments on remote IR...spectroscopy standoff detection of explosives; published chapter on state of art of vibrational spectroscopy standoff detection of explosives

  5. Thermal-mechanical-chemical responses of polymer-bonded explosives using a mesoscopic reactive model under impact loading.

    Science.gov (United States)

    Wang, XinJie; Wu, YanQing; Huang, FengLei

    2017-01-05

    A mesoscopic framework is developed to quantify the thermal-mechanical-chemical responses of polymer-bonded explosive (PBX) samples under impact loading. A mesoscopic reactive model is developed for the cyclotetramethylenetetranitramine (HMX) crystal, which incorporates nonlinear elasticity, crystal plasticity, and temperature-dependent chemical reaction. The proposed model was implemented in the finite element code ABAQUS by the user subroutine VUMAT. A series of three-dimensional mesoscale models were constructed and calculated under low-strength impact loading scenarios from 100m/s to 600m/s where only the first wave transit is studied. Crystal anisotropy and microstructural heterogeneity are responsible for the nonuniform stress field and fluctuations of the stress wave front. At a critical impact velocity (≥300m/s), a chemical reaction is triggered because the temperature contributed by the volumetric and plastic works is sufficiently high. Physical quantities, including stress, temperature, and extent of reaction, are homogenized from those across the microstructure at the mesoscale to compare with macroscale measurements, which will advance the continuum-level models. The framework presented in this study has important implications in understanding hot spot ignition processes and improving predictive capabilities in energetic materials. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Dielectric Sensing of Toxic and Explosive Chemicals via Impedance Spectroscopy and Plasmonic Resonance

    Science.gov (United States)

    2017-05-07

    to identify material(s) that have interaction potential with chemicals of interest. In particular, specific reaction chemistry allows for resulting...chemicals of interest. In particular, specific reaction chemistry allows for resulting materials to exhibit specificity. Based on the most favorable...effects in a significant fraction of the population. Although fine for a military advance team, this sensor is not adequate for defense applications

  7. Combined Biological and Chemical Mechanisms for Degradation of Insensitive Munitions in the Presence of Alternate Explosives

    Science.gov (United States)

    2017-06-21

    research was to quantify the rate and extent to which IM can be transformed by combined biological and chemical reactions with iron and Fe(III...in battle conditions. The objective of this research was to quantify the rate and extent to which IM can be transformed by combined biological and...MATERIALS AND METHODS ................................................................. 10 III. IRON AND ELECTRON SHUTTLE MEDIATED DEGRADATION OF

  8. Characterization of the improvised explosive urea nitrate using electrospray ionization and atmospheric pressure chemical ionization.

    Science.gov (United States)

    Tamiri, Tsippy

    2005-01-01

    Mass spectra of urea nitrate were measured in electrospray ionization and in atmospheric pressure chemical ionization in the negative mode. In both ionization methods two characteristic adduct ions containing the intact molecule [urea nitrate+NO3]- and [urea nitrate+HNO3+NO3]- are shown. The structure of the two adduct ions was deduced using measurements of isotopically labeled urea nitrate. Collision-induced dissociation measurements of the adduct ions show typical losses enabling the identification of urea nitrate in trace amounts. Using these methods urea nitrate was identified in real cases. Copyright (c) 2005 John Wiley & Sons, Ltd.

  9. [A nitrite poisoning event associated with intentional chemical releases].

    Science.gov (United States)

    Li, Gang; Li, Bin; Lin, Lin; Zhang, Mao-tang; Liu, Qu; Huang, Wei; Xie, Xian-qing; Chen, Lin; Zhang, Shun-xiang

    2013-04-01

    To compare the field epidemiological investigation and the criminal investigation on a nitrite poisoning event caused by deliberate contamination. Cases were searched according to the definition of the disease. Information on the histories of onset and diet of all the cases and normal population on site, were investigated face to face. Information as ingredients, processing and sales of foods was also gathered. Samples were collected and nitrite detection were performed. Relevant materials were searched, cases were interviewed and data related to criminal results were collected. Poisoned persons were staff of a big company in Longgang district of Shenzhen. The overall attack rate was 56.25% (63/112), with suspected and confirmed rates as 41.96% and 14.28%, respectively. The fatality rate was 3.17% (2/63). Clinical manifestation and effect of treatment were in accordance with the characteristics of an episode related to acute nitrite food poisoning in terms of factors as the time of onset, involving different age, sex and jobs of the patients. A total of 191 samples, including vomits from patients and seven batches of food and environment samples, were collected, with a positive detected rate of nitrite as 18.84%. Information gathered from the field environment, food distribution and processing supported the assumption that this was an incident of nitrite poisoning event with intention. from the criminal investigation showed that the suspect stemmed from the market management rivalry, bought nitrite, dissolved and spread on food stalls F9 and F10. This event of intentional nitrite release resulting in food contamination which further leading to food poisoning, was completely proved by the joint efforts of the teams and expertise from the field epidemiology survey and the criminal investigation.

  10. Luminescent metal-organic frameworks for chemical sensing and explosive detection.

    Science.gov (United States)

    Hu, Zhichao; Deibert, Benjamin J; Li, Jing

    2014-08-21

    Metal-organic frameworks (MOFs) are a unique class of crystalline solids comprised of metal cations (or metal clusters) and organic ligands that have shown promise for a wide variety of applications. Over the past 15 years, research and development of these materials have become one of the most intensely and extensively pursued areas. A very interesting and well-investigated topic is their optical emission properties and related applications. Several reviews have provided a comprehensive overview covering many aspects of the subject up to 2011. This review intends to provide an update of work published since then and focuses on the photoluminescence (PL) properties of MOFs and their possible utility in chemical and biological sensing and detection. The spectrum of this review includes the origin of luminescence in MOFs, the advantages of luminescent MOF (LMOF) based sensors, general strategies in designing sensory materials, and examples of various applications in sensing and detection.

  11. Express analysis of explosives, chemical warfare agents and drugs with multicapillary column gas chromatography and ion mobility increment spectrometry.

    Science.gov (United States)

    Buryakov, Igor A

    2004-02-05

    Description of a gas chromatograph designed for express analysis of explosives (2,4-dinitrotoluene, 2,4,6-trinitrotoluene, pentaerythritol tetranitrate), chemical warfare agents (mustard gas, lewisite, sarin) and drugs (heroin, cocaine hydrochloride, crack) is given. The devices comprises a multicapillary chromatographic column and an ion mobility increment spectrometer (MCC-IMIS). The main analytical characteristics of an IMIS (estimated detection limit (DL), linear dynamic range (LDR), speed of response) and a chromatographic column (separation power, degree of separation, a number of possible peaks at a chromatogram section, divided by analysis time) are determined. The maximum value of DL equal to 5 pg/ml was registered for cis-alpha-LW, and the lowest one of 0.001 pg/ml was for cocaine. The maximum value of LDR equal to 1000 was registered for sarin and the lowest one of 150 was for the ions of lewisite. Speed of response of one compound detection with the IMIS was 0.7 s.

  12. A review of explosion prevention and protection systems suitable as ultimate layer of protection in chemical process installations

    NARCIS (Netherlands)

    Pekalski, A.A.; Zevenbergen, J.F.; Lemkowitz, S.M.; Pasman, H.J.

    2005-01-01

    Ideally, explosion risk is identified and prevented at an early stage of process design, forming a key part of the inherently safer design (ISD) approach. However, in practice, explosion risk often cannot be eliminated completely. Reliable preventive and protective systems must therefore be applied,

  13. Development of a handheld widefield hyperspectral imaging (HSI) sensor for standoff detection of explosive, chemical, and narcotic residues

    Science.gov (United States)

    Nelson, Matthew P.; Basta, Andrew; Patil, Raju; Klueva, Oksana; Treado, Patrick J.

    2013-05-01

    The utility of Hyper Spectral Imaging (HSI) passive chemical detection employing wide field, standoff imaging continues to be advanced in detection applications. With a drive for reduced SWaP (Size, Weight, and Power), increased speed of detection and sensitivity, developing a handheld platform that is robust and user-friendly increases the detection capabilities of the end user. In addition, easy to use handheld detectors could improve the effectiveness of locating and identifying threats while reducing risks to the individual. ChemImage Sensor Systems (CISS) has developed the HSI Aperio™ sensor for real time, wide area surveillance and standoff detection of explosives, chemical threats, and narcotics for use in both government and commercial contexts. Employing liquid crystal tunable filter technology, the HSI system has an intuitive user interface that produces automated detections and real-time display of threats with an end user created library of threat signatures that is easily updated allowing for new hazardous materials. Unlike existing detection technologies that often require close proximity for sensing and so endanger operators and costly equipment, the handheld sensor allows the individual operator to detect threats from a safe distance. Uses of the sensor include locating production facilities of illegal drugs or IEDs by identification of materials on surfaces such as walls, floors, doors, deposits on production tools and residue on individuals. In addition, the sensor can be used for longer-range standoff applications such as hasty checkpoint or vehicle inspection of residue materials on surfaces or bulk material identification. The CISS Aperio™ sensor has faster data collection, faster image processing, and increased detection capability compared to previous sensors.

  14. Single Particle Analysis by Combined Chemical Imaging to Study Episodic Air Pollution Events in Vienna

    Science.gov (United States)

    Ofner, Johannes; Eitenberger, Elisabeth; Friedbacher, Gernot; Brenner, Florian; Hutter, Herbert; Schauer, Gerhard; Kistler, Magdalena; Greilinger, Marion; Lohninger, Hans; Lendl, Bernhard; Kasper-Giebl, Anne

    2017-04-01

    The aerosol composition of a city like Vienna is characterized by a complex interaction of local emissions and atmospheric input on a regional and continental scale. The identification of major aerosol constituents for basic source appointment and air quality issues needs a high analytical effort. Exceptional episodic air pollution events strongly change the typical aerosol composition of a city like Vienna on a time-scale of few hours to several days. Analyzing the chemistry of particulate matter from these events is often hampered by the sampling time and related sample amount necessary to apply the full range of bulk analytical methods needed for chemical characterization. Additionally, morphological and single particle features are hardly accessible. Chemical Imaging evolved to a powerful tool for image-based chemical analysis of complex samples. As a complementary technique to bulk analytical methods, chemical imaging can address a new access to study air pollution events by obtaining major aerosol constituents with single particle features at high temporal resolutions and small sample volumes. The analysis of the chemical imaging datasets is assisted by multivariate statistics with the benefit of image-based chemical structure determination for direct aerosol source appointment. A novel approach in chemical imaging is combined chemical imaging or so-called multisensor hyperspectral imaging, involving elemental imaging (electron microscopy-based energy dispersive X-ray imaging), vibrational imaging (Raman micro-spectroscopy) and mass spectrometric imaging (Time-of-Flight Secondary Ion Mass Spectrometry) with subsequent combined multivariate analytics. Combined chemical imaging of precipitated aerosol particles will be demonstrated by the following examples of air pollution events in Vienna: Exceptional episodic events like the transformation of Saharan dust by the impact of the city of Vienna will be discussed and compared to samples obtained at a high alpine

  15. In situ trace detection of peroxide explosives by desorption electrospray ionization and desorption atmospheric pressure chemical ionization.

    Science.gov (United States)

    Cotte-Rodríguez, Ismael; Hernandez-Soto, Heriberto; Chen, Hao; Cooks, R Graham

    2008-03-01

    Desorption electrospray ionization (DESI) mass spectrometry is used for the rapid (process triggered by an unusual homolytic cleavage of the peroxide bond, forming a distonic ion. This is followed by elimination of a fragment of 30 mass units, shown to be the expected neutral molecule, formaldehyde, in the case of HMTD, but shown by isotopic labeling experiments to be ethane in the cases of TATP and TrATrP. Density functional theory (DFT) calculations support the suggested fragmentation mechanisms for the complexes. Binding energies of Na+ of 40.2 and 33.1 kcal/mol were calculated for TATP-Na(+) and HMTD-Na(+) complexes, suggesting a strong interaction between the peroxide groups and the sodium ion. Increased selectivity is obtained either by MS/MS or by doping the spray solvent with additives that produce the lithium and potassium complexes of TATP, HMTD, and TrATrP. Addition of dopants into the solvent spray increased the signal intensity by an order of magnitude. When pure alcohol or aqueous hydrogen peroxide was used as the spray solvent, the (HMTD + Na)+ complex was able to bind a molecule of alcohol (methanol or ethanol) or hydrogen peroxide, providing additional characteristic ions to increase the selectivity of analysis. DESI also allowed the rapid detection of peroxide explosives in complex matrixes such as diesel fuel and lubricants using single or multiple cation additives (Na(+), K(+), and Li(+), and NH4(+)) in the spray solvent. Low-nanogram detection limits were achieved for HMTD, TrATrP, and TATP in these complex matrixes. The DESI response was linear over 3 orders of magnitude for HMTD and TATP on paper surfaces (1-5000 ng), and quantification of both peroxide explosives from paper gave precisions (RSD) of less than 3%. The use of pure water and compressed air as the DESI spray solution and nebulizing gas, respectively, showed similar ionization efficiencies to those obtained using methanol/water mixtures and nitrogen gas (the typical choices). An

  16. Chemical and explosives point detection through opaque containers using spatially offset Raman spectroscopy (SORS)

    Science.gov (United States)

    Loeffen, Paul W.; Maskall, Guy; Bonthron, Stuart; Bloomfield, Matthew; Tombling, Craig; Matousek, Pavel

    2011-05-01

    Spatially Offset Raman Spectroscopy (SORS) is a novel technique used to identify the chemical Raman signature of threat materials within a few seconds through common non-metallic containers, including those containers which may not yield to inspection by conventional backscatter Raman. In particular, some opaque plastic containers and coloured glass bottles can be difficult to analyze using conventional backscatter Raman because the signal from the contents is often overwhelmed by the much stronger Raman signal and/or fluorescence originating from the container itself. SORS overcomes these difficulties and generates clean Raman spectra from both the container and the contents with no prior knowledge of either. This is achieved by making two, or more, Raman measurements at various offsets between the collection and illumination areas, each containing different proportions of the fingerprint signals from the container and content materials. Using scaled subtraction, or multivariate statistical methods, the two orthogonal signals can be separated numerically, thereby providing a clean Raman spectrum of the contents without contamination from the container. Consequently, SORS promises to significantly improve threat detection capability and decrease the falsealarm rate compared with conventional Raman spectroscopy making it considerably more suitable as an alarm resolution methodology (e.g. at airports). In this paper, the technique and method are described and a study of offset value optimization is described illustrating the difference between one and two fixed spatial offsets. It is concluded that two fixed offsets yield an improvement in the SORS measurement which will help maximize the threat detection capability.

  17. Tropical shoreline ice in the late Cambrian: Implications for earth's climate between the Cambrian Explosion and the Great Ordovician Biodiversification Event

    Science.gov (United States)

    Runkel, Anthony C.; MacKey, T.J.; Cowan, Clinton A.; Fox, David L.

    2010-01-01

    Middle to late Cambrian time (ca. 513 to 488 Ma) is characterized by an unstable plateau in biodiversity, when depauperate shelf faunas suffered repeated extinctions. This poorly understood interval separates the Cambrian Explosion from the Great Ordovician Biodiversification Event and is generally regarded as a time of sustained greenhouse conditions. We present evidence that suggests a drastically different climate during this enigmatic interval: Features indicative of meteoric ice are well preserved in late Cambrian equatorial beach deposits that correspond to one of the shelf extinction events. Thus, the middle to late Cambrian Earth was at least episodically cold and might best be considered a muted analogue to the environmental extremes that characterized the Proterozoic, even though cooling in the two periods may have occurred in response to different triggers. Such later Cambrian conditions may have significantly impacted evolution preceding the Ordovician radiation.

  18. Explosive Components Facility

    Data.gov (United States)

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

  19. Chemical analysis of pharmaceuticals and explosives in fingermarks using matrix-assisted laser desorption ionization/time-of-flight mass spectrometry.

    Science.gov (United States)

    Kaplan-Sandquist, Kimberly; LeBeau, Marc A; Miller, Mark L

    2014-02-01

    Chemical analysis of latent fingermarks, "touch chemistry," has the potential of providing intelligence or forensically relevant information. Matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (MALDI/TOF MS) was used as an analytical platform for obtaining mass spectra and chemical images of target drugs and explosives in fingermark residues following conventional fingerprint development methods and MALDI matrix processing. There were two main purposes of this research: (1) develop effective laboratory methods for detecting drugs and explosives in fingermark residues and (2) determine the feasibility of detecting drugs and explosives after casual contact with pills, powders, and residues. Further, synthetic latent print reference pads were evaluated as mimics of natural fingermark residue to determine if the pads could be used for method development and quality control. The results suggest that artificial amino acid and sebaceous oil residue pads are not suitable to adequately simulate natural fingermark chemistry for MALDI/TOF MS analysis. However, the pads were useful for designing experiments and setting instrumental parameters. Based on the natural fingermark residue experiments, handling whole or broken pills did not transfer sufficient quantities of drugs to allow for definitive detection. Transferring drugs or explosives in the form of powders and residues was successful for preparing analytes for detection after contact with fingers and deposition of fingermark residue. One downfall to handling powders was that the analyte particles were easily spread beyond the original fingermark during development. Analyte particles were confined in the original fingermark when using transfer residues. The MALDI/TOF MS was able to detect procaine, pseudoephedrine, TNT, and RDX from contact residue under laboratory conditions with the integration of conventional fingerprint development methods and MALDI matrix. MALDI/TOF MS is a nondestructive

  20. Explosives tester

    Science.gov (United States)

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

    2011-01-11

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

  1. Real-time, wide-area hyperspectral imaging sensors for standoff detection of explosives and chemical warfare agents

    Science.gov (United States)

    Gomer, Nathaniel R.; Tazik, Shawna; Gardner, Charles W.; Nelson, Matthew P.

    2017-05-01

    Hyperspectral imaging (HSI) is a valuable tool for the detection and analysis of targets located within complex backgrounds. HSI can detect threat materials on environmental surfaces, where the concentration of the target of interest is often very low and is typically found within complex scenery. Unfortunately, current generation HSI systems have size, weight, and power limitations that prohibit their use for field-portable and/or real-time applications. Current generation systems commonly provide an inefficient area search rate, require close proximity to the target for screening, and/or are not capable of making real-time measurements. ChemImage Sensor Systems (CISS) is developing a variety of real-time, wide-field hyperspectral imaging systems that utilize shortwave infrared (SWIR) absorption and Raman spectroscopy. SWIR HSI sensors provide wide-area imagery with at or near real time detection speeds. Raman HSI sensors are being developed to overcome two obstacles present in standard Raman detection systems: slow area search rate (due to small laser spot sizes) and lack of eye-safety. SWIR HSI sensors have been integrated into mobile, robot based platforms and handheld variants for the detection of explosives and chemical warfare agents (CWAs). In addition, the fusion of these two technologies into a single system has shown the feasibility of using both techniques concurrently to provide higher probability of detection and lower false alarm rates. This paper will provide background on Raman and SWIR HSI, discuss the applications for these techniques, and provide an overview of novel CISS HSI sensors focusing on sensor design and detection results.

  2. Handheld and mobile hyperspectral imaging sensors for wide-area standoff detection of explosives and chemical warfare agents

    Science.gov (United States)

    Gomer, Nathaniel R.; Gardner, Charles W.; Nelson, Matthew P.

    2016-05-01

    Hyperspectral imaging (HSI) is a valuable tool for the investigation and analysis of targets in complex background with a high degree of autonomy. HSI is beneficial for the detection of threat materials on environmental surfaces, where the concentration of the target of interest is often very low and is typically found within complex scenery. Two HSI techniques that have proven to be valuable are Raman and shortwave infrared (SWIR) HSI. Unfortunately, current generation HSI systems have numerous size, weight, and power (SWaP) limitations that make their potential integration onto a handheld or field portable platform difficult. The systems that are field-portable do so by sacrificing system performance, typically by providing an inefficient area search rate, requiring close proximity to the target for screening, and/or eliminating the potential to conduct real-time measurements. To address these shortcomings, ChemImage Sensor Systems (CISS) is developing a variety of wide-field hyperspectral imaging systems. Raman HSI sensors are being developed to overcome two obstacles present in standard Raman detection systems: slow area search rate (due to small laser spot sizes) and lack of eye-safety. SWIR HSI sensors have been integrated into mobile, robot based platforms and handheld variants for the detection of explosives and chemical warfare agents (CWAs). In addition, the fusion of these two technologies into a single system has shown the feasibility of using both techniques concurrently to provide higher probability of detection and lower false alarm rates. This paper will provide background on Raman and SWIR HSI, discuss the applications for these techniques, and provide an overview of novel CISS HSI sensors focused on sensor design and detection results.

  3. Regional Seismic Methods of Identifying Explosions

    Science.gov (United States)

    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

  4. Paleoenvironmental changes affected on the diversity explosion and extinction events of the fossil diatom resting spore assemblage across the E/O boundary

    Science.gov (United States)

    Suto, I.; Jordan, R. W.; Watanabe, M.

    2007-12-01

    The marine diatom genus Chaetoceros is known as a major contributor to primary production in near-shore upwelling regions and coastal areas, where it accounts for 20-25% of the total marine primary production. They produce heavily silicified resting spores which are easily preserved as fossils under nutrient-poor conditions. The diatom resting spores are therefore preserved as significant constituents in fossil marine diatom assemblages providing useful information for reconstructing paleoproductivity and paleoenvironmental changes. However, due to the importance of Chaetoceros in marine primary production, it is crucial to investigate fossil resting spores in upwelling regions. As the result of revising the taxonomy of fossil diatom Chaetoceros resting spores using DSDP 338, 436 and 438, and onland-samples (Newport Beach Section, California) from the late Eocene to the Recent, the Chaetoceros Explosion Event (when there was an increase in diversity and abundance, and a 50% reduction in valve size) across the Eocene/Oligocene (E/O) boundary was clarified. On the other hand, investigation of middle Eocene samples from the Integrated Ocean Drilling Program (IODP) Expedition 302, revealed an Extinction Event across the E/O boundary of diatom resting spores other than Chaetoceros. These two events indicate increased amounts of nutrient supply via upwelling and a change from a stable water column with a constant nutrient supply in the Eocene to an unstable one with sporadic nutrient supply due to increased vertical mixing in the Oligocene.

  5. ACUTE EFFECTS OF PRE-EVENT LOWER LIMB MASSAGE ON EXPLOSIVE AND HIGH SPEED MOTOR CAPACITIES AND FLEXIBILITY

    Directory of Open Access Journals (Sweden)

    Ramiz Arabaci

    2008-12-01

    Full Text Available The aim of this study was to examine the acute effects of pre- performance lower limb massage after warm-up on explosive and high-speed motor capacities and flexibility. Twenty-four physically active healthy Caucasian male subjects volunteered to participate in this study. All subjects were from a Physical Education and Sport Department in a large university in Turkey. The study had a counterbalanced crossover design. Each of the subjects applied the following intervention protocols in a randomised order; (a massage, (b stretching, and (c rest. Before (pre and after (post each of the interventions, the 10 meter acceleration (AS, flying start 20 meter sprint (FS, 30 meter sprint from standing position (TS, leg reaction time (LR, vertical jump (VJ and sit & reach (SR tests were performed. A Wilcoxon's signed rank test was used to compare before and after test values within the three interventions (massage, stretching and rest. The data showed a significant worsening, after massage and stretching interventions, in the VJ, LR (only in stretching intervention, AS and TS tests (p < 0.05, and significant improvement in the SR test (p < 0.05. In contrast, the rest intervention led only to a significant decrement in TS performance (p < 0.05. In conclusion, the present findings suggest that performing 10 minute posterior and 5 minute anterior lower limb Swedish massage has an adverse effect on vertical jump, speed, and reaction time, and a positive effect on sit and reach test results

  6. Sulfate Aerosols from Non-Explosive Volcanoes: Chemical-Radiative Effects in the Troposphere and Lower Stratosphere

    Directory of Open Access Journals (Sweden)

    Giovanni Pitari

    2016-06-01

    Full Text Available SO2 and H2S are the two most important gas-phase sulfur species emitted by volcanoes, with a global amount from non-explosive emissions of the order 10 Tg-S/yr. These gases are readily oxidized forming SO42− aerosols, which effectively scatter the incoming solar radiation and cool the surface. They also perturb atmospheric chemistry by enhancing the NOx to HNO3 heterogeneous conversion via hydrolysis on the aerosol surface of N2O5 and Br-Cl nitrates. This reduces formation of tropospheric O3 and the OH to HO2 ratio, thus limiting the oxidation of CH4 and increasing its lifetime. In addition to this tropospheric chemistry perturbation, there is also an impact on the NOx heterogeneous chemistry in the lower stratosphere, due to vertical transport of volcanic SO2 up to the tropical tropopause layer. Furthermore, the stratospheric O3 formation and loss, as well as the NOx budget, may be slightly affected by the additional amount of upward diffused solar radiation and consequent increase of photolysis rates. Two multi-decadal time-slice runs of a climate-chemistry-aerosol model have been designed for studying these chemical-radiative effects. A tropopause mean global net radiative flux change (RF of −0.23 W·m−2 is calculated (including direct and indirect aerosol effects with a 14% increase of the global mean sulfate aerosol optical depth. A 5–15 ppt NOx decrease is found in the mid-troposphere subtropics and mid-latitudes and also from pole to pole in the lower stratosphere. The tropospheric NOx perturbation triggers a column O3 decrease of 0.5–1.5 DU and a 1.1% increase of the CH4 lifetime. The surface cooling induced by solar radiation scattering by the volcanic aerosols induces a tropospheric stabilization with reduced updraft velocities that produce ice supersaturation conditions in the upper troposphere. A global mean 0.9% decrease of the cirrus ice optical depth is calculated with an indirect RF of −0.08 W·m−2.

  7. Lessons Learned from Near Field Modeling and Data Collected at the SPE Chemical Explosions in Jointed Rock Masses

    Science.gov (United States)

    Vorobiev, O.; Ezzedine, S. M.; Hurley, R.; Antoun, T.; Glenn, L.

    2016-12-01

    This work describes the near-field modeling of wave propagation from underground chemicalexplosions conducted at the Nevada National Security Site (NNSS) in fractured granitic rock. Lab testsperformed on granite samples excavated from various locations at the SPE site have shown littlevariability in mechanical properties. Granite at this scale can be considered as an isotropic medium. Wehave shown, however, that on the scale of the pressure waves generated during chemical explosions(tens of meters), the effective mechanical properties may vary significantly and exhibit both elastic andplastic anisotropies due to local variations in joint properties such as spacing orientation, joint aperture,cohesion and saturation. Since including every joint in a discrete fashion in computational model is notfeasible, especially for large-scale calculations ( 1.5 km domain), we have developed a computationaltechnique to upscale mechanical properties for various scales (frequencies) using geophysicalcharacterization conducted during recent SPE tests at the NNSS. Stochastic representation of thesefeatures based on the field characterizations has been implemented into LLNL's Geodyn-L hydrocode.Scale dependency in mechanical properties is important in order to understand how the ground motionscales with yield. We hope that such an approach will not only provide a better prediction of theground motion observed in the SPE (where the yield varies from 100 kg to few tons of TNT equivalent)but also will allow us to extrapolate results of the SPE to sources with bigger yields. We have validatedour computational results by comparing the measured and computed ground motion at various rangesfor experiments of various yields (SPE1-SPE5). Using the new model we performed severalcomputational studies to identify the most important mechanical properties of the rock mass specific tothe SPE site and to understand their roles in the observed ground motion in the near-field. We willpresent a series

  8. Pool chemical--associated health events in public and residential settings - United States, 1983-2007.

    Science.gov (United States)

    2009-05-15

    Swimming is the second most popular exercise in the United States, with approximately 339 million swimming visits to recreational water venues, including disinfected ones (e.g., pools, water parks, and interactive fountains), each year. Pool chemicals are added to the water in these venues to prevent transmission of infectious pathogens. These chemicals can cause injury when handled inappropriately or when operators fail to use appropriate personal protective equipment. This report summarizes 36 pool chemical--associated health events reported to the New York State Department of Health (NYSDOH) for public aquatic venues during 1983--2006 and includes analyses of 1998-2007 data from the National Electronic Injury Surveillance System (NEISS) and 2007 data from the National Poison Data System (NPDS). NYSDOH reported primarily summertime health events resulting in acute respiratory illness. NEISS and NPDS data revealed that pool chemical--associated injuries or exposures led to thousands of estimated annual emergency department (ED) visits or actual poison center consultations, respectively. These pool chemical--associated health events can be prevented through 1) improved design and engineering and 2) education and training that stresses safe pool-chemical handling and storage practices and safe and preventive maintenance of equipment.

  9. Effects of charge design features on parameters of acoustic and seismic waves and cratering, for SMR chemical surface explosions

    Science.gov (United States)

    Gitterman, Y.

    2012-04-01

    A series of experimental on-surface shots was designed and conducted by the Geophysical Institute of Israel at Sayarim Military Range (SMR) in Negev desert, including two large calibration explosions: about 82 tons of strong IMI explosives in August 2009, and about 100 tons of ANFO explosives in January 2011. It was a collaborative effort between Israel, CTBTO, USA and several European countries, with the main goal to provide fully controlled ground truth (GT0) infrasound sources in different weather/wind conditions, for calibration of IMS infrasound stations in Europe, Middle East and Asia. Strong boosters and the upward charge detonation scheme were applied to provide a reduced energy release to the ground and an enlarged energy radiation to the atmosphere, producing enhanced infrasound signals, for better observation at far-regional stations. The following observations and results indicate on the required explosives energy partition for this charge design: 1) crater size and local seismic (duration) magnitudes were found smaller than expected for these large surface explosions; 2) small test shots of the same charge (1 ton) conducted at SMR with different detonation directions showed clearly lower seismic amplitudes/energy and smaller crater size for the upward detonation; 3) many infrasound stations at local and regional distances showed higher than expected peak amplitudes, even after application of a wind-correction procedure. For the large-scale explosions, high-pressure gauges were deployed at 100-600 m to record air-blast properties, evaluate the efficiency of the charge design and energy generation, and provide a reliable estimation of the charge yield. Empirical relations for air-blast parameters - peak pressure, impulse and the Secondary Shock (SS) time delay - depending on distance, were developed and analyzed. The parameters, scaled by the cubic root of estimated TNT equivalent charges, were found consistent for all analyzed explosions, except of SS

  10. Variations in Aerosol Chemical Composition during New Particle Formation and Growth Events Downwind of Seoul, Korea

    Science.gov (United States)

    Park, J.; Choi, Y.; Ghim, Y. S.

    2016-12-01

    New particle formation and growth has been characterized through various field studies using scanning mobility particle sizer (SMPS). However, there is insufficient knowledge of the variation of aerosol chemical compositions during those events. We investigated the variation of aerosol chemical composition during new particle formation and growth events downwind of Seoul. New particle formation and growth events were identified based on the evolution of the number size distribution measured by SMPS. The concentrations of inorganic ions and black carbon were measured using a particle-into-liquid sampler (PILS) coupled with an ion chromatograph (IC) and multi-angle absorption photometer (MAAP), respectively. We also measured concentrations of gaseous precursors (SO2, NO2) along with meteorological parameters using an automatic weather station. The measurements were conducted on the rooftop of a five-story building on a hill (37.34°N, 127.27°E, 167 m above sea level) at the Global Campus of Hankuk University of Foreign Studies, located about 35 km southeast of downtown Seoul. The measurement periods were from February 12 to April 1, 2015 and from April 13 to June 12, 2016. We investigated the difference in chemical compositions between event and non-event days and its association with the variations in precursor concentrations and meteorological parameters.

  11. Comparison of ground motion from tremors and explosions in deep gold mines

    Science.gov (United States)

    McGarr, A.; Bicknell, J.; Churcher, J.; Spottiswoode, S.

    1990-01-01

    Seismic body waves, from tamped chemical explosions, two with yields of 50 and one of 150 kg, were compared with corresponding data from three mining-induced tremors with a view to testing methods of discriminating between the two types of events. It is concluded that for events of fixed low-frequency spectral asymptotes, the explosions typically have higher corner frequencies than tremors or earthquakes, although counterexamples certainly exist. Interestingly, the 150-kg explosion was identified as such on the basis of P and S wave polarities that are incompatible with the normally expected double-couple source model; instead these initial motions are consistent with an explosion in conjunction with normal faulting. The body wave spectra of this explosion and those of a nearby tremor, however, were indistinguishable. -from Authors

  12. Human and organizational factors in Chinese hazardous chemical accidents: a case study of the '8.12' Tianjin Port fire and explosion using the HFACS-HC.

    Science.gov (United States)

    Zhou, Lin; Fu, Gui; Xue, Yujingyang

    2017-11-07

    Human and organizational factors have been proven to be the prime causes of Chinese hazardous chemical accidents (HCAs). A modified version of the Human Factors Analysis and Classification System (HFACS), namely the HFACS-Hazardous Chemicals (HC), was developed to identify the human factors involved in Chinese HCAs. The '8.12' Tianjin Port fire and explosion, the costliest HCA in recent years, was reanalyzed using this framework, and the results were compared with the official accident inquiry report to determine their differences related to the identification of human and organizational factors. The study revealed that interacting human factors from different levels in Ruihai Company led to this catastrophe, and the inquiry report had limitations in the identification of human factors and the guidance for similar accident prevention. This study showed the applicability of the HFACS-HC in HCA analyses as well as the necessity to recommend this approach for future HCA investigations.

  13. Accident investigation board report on the May 14, 1997, chemical explosion at the Plutonium Reclamation Facility, Hanford Site,Richland, Washington - summary report

    Energy Technology Data Exchange (ETDEWEB)

    Gerton, R.E.

    1997-08-07

    This report is a summary of the Accident Investigation Board Report on the May 14, 1997, Chemical Explosion at the Plutonium Reclamation Facility, Hanford Site, Richland, Washington (DOE/RL-97-59). The referenced report provides a greater level of detail and includes a complete discussion of the facts identified, analysis of those facts, conclusions derived from the analysis, identification of the accident`s causal factors, and recommendations that should be addressed through follow-up action by the U.S. Department of Energy and its contractors. This companion document provides a concise summary of that report, with emphasis on management issues. Evaluation of emergency and occupational health response to, and radiological and chemical releases from, this accident was not within the scope of this investigation, but is the subject of a separate investigation and report (see DOE/RL-97-62).

  14. Liquid explosives

    CERN Document Server

    Liu, Jiping

    2015-01-01

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

  15. Biodegradation of nitro-explosives.

    Science.gov (United States)

    Kanekar, Pradnya; Dautpure, Premlata; Sarnaik, Seema

    2003-09-01

    Environmental contamination by nitro compounds is associated principally with the explosives industry. However, global production and use of explosives is unavoidable. The presently widely used nitro-explosives are TNT (Trinitrotoluene), RDX (Royal Demolition Explosive) and HMX (High Melting Explosive). Nevertheless, the problems of these nitro-explosives are almost parallel due to their similarities of production processes, abundance of nitro-explosives and resembling chemical structures. The nitro-explosives per se as well as their environmental transformation products are toxic, showing symptoms as methaemoglobinaemia, kidney trouble, jaundice etc. Hence their removal/degradation from soil/water is essential. Aerobic and anaerobic degradation of TNT and RDX have been reported, while for HMX anaerobic or anoxic degradation have been described in many studies. A multisystem involvement using plants in remediation is gaining importance. Thus the information about degradation of nitro-explosives is available in jigsaw pieces which needs to be arranged and lacunae filled to get concrete degradative schemes so that environmental pollution from nitro-explosives can be dealt with more successfully at a macroscale. An overview of the reports on nitro-explosives degradation, future outlook and studies done by us are presented in this review.

  16. Does Explosive Nuclear Burning Occur in Tidal Disruption Events of White Dwarfs by Intermediate-mass Black Holes?

    Energy Technology Data Exchange (ETDEWEB)

    Tanikawa, Ataru; Sato, Yushi; Hachisu, Izumi [Department of Earth Science and Astronomy, College of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Nomoto, Ken’ichi; Maeda, Keiichi [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Nakasato, Naohito, E-mail: tanikawa@ea.c.u-tokyo.ac.jp [Department of Computer Science and Engineering, University of Aizu, Tsuruga Ikki-machi Aizu-Wakamatsu, Fukushima 965-8580 (Japan)

    2017-04-20

    We investigate nucleosynthesis in tidal disruption events (TDEs) of white dwarfs (WDs) by intermediate-mass black holes. We consider various types of WDs with different masses and compositions by means of three-dimensional (3D) smoothed particle hydrodynamics (SPH) simulations. We model these WDs with different numbers of SPH particles, N , from a few 10{sup 4} to a few 10{sup 7} in order to check mass resolution convergence, where SPH simulations with N > 10{sup 7} (or a space resolution of several 10{sup 6} cm) have unprecedentedly high resolution in this kind of simulation. We find that nuclear reactions become less active with increasing N and that these nuclear reactions are excited by spurious heating due to low resolution. Moreover, we find no shock wave generation. In order to investigate the reason for the absence of a shock wave, we additionally perform one-dimensional (1D) SPH and mesh-based simulations with a space resolution ranging from 10{sup 4} to 10{sup 7} cm, using a characteristic flow structure extracted from the 3D SPH simulations. We find shock waves in these 1D high-resolution simulations, one of which triggers a detonation wave. However, we must be careful of the fact that, if the shock wave emerged in an outer region, it could not trigger the detonation wave due to low density. Note that the 1D initial conditions lack accuracy to precisely determine where a shock wave emerges. We need to perform 3D simulations with ≲10{sup 6} cm space resolution in order to conclude that WD TDEs become optical transients powered by radioactive nuclei.

  17. A Computational Approach to Extinction Events in Chemical Reaction Networks with Discrete State Spaces

    OpenAIRE

    Johnston, Matthew D.

    2017-01-01

    Recent work of M.D. Johnston et al. has produced sufficient conditions on the structure of a chemical reaction network which guarantee that the corresponding discrete state space system exhibits an extinction event. The conditions consist of a series of systems of equalities and inequalities on the edges of a modified reaction network called a domination-expanded reaction network. In this paper, we present a computational implementation of these conditions written in Python and apply the prog...

  18. Transport and chemical evolution of trace species following convective events during DC3

    Science.gov (United States)

    Apel, E. C.; Hornbrook, R. S.; Hills, A. J.; Emmons, L. K.; Weinheimer, A. J.; Knapp, D. J.; Campos, T. L.; Flocke, F. M.; Fried, A.; Weibring, P.; Richter, D.; Ryerson, T. B.; Olson, J. R.; Wisthaler, A.; Blake, D. R.; Blake, N. J.; Riemer, D. D.

    2013-12-01

    A wide range of trace species including more than 50 volatile organic compounds (VOCs) were measured during the Deep Convective Cloud and Chemistry (DC3) experiment. The NCAR Trace Organic Gas Analyzer (TOGA) measured VOCs on board the NSF GV aircraft and the UCI Whole Air Sampler (WAS) and University of Innsbruck PTR-MS measured VOCs on board the NASA DC8. Coordinated flights between the two aircraft produced a rich dataset that aimed to characterize the inflow and outflow of convective events. Because of the wide range of solubilities and reactivities the suite of measured VOCs encompasses, these species provide critical information on the transport and chemical and/or physical processing occurring through the storm systems as well as the chemical evolution observed in the outflow following convective events. All of these processes have a direct influence on the oxidant chemistry perturbations that occur in the upper troposphere following such events. This influence is quantified with observations and modeling of the chemical outflow from selected storms during DC3.

  19. Calculations on seismic coupling of underground explosions in salt

    Energy Technology Data Exchange (ETDEWEB)

    Heusinkveld, M.E.

    1981-01-20

    This report details the results of a theoretical study of seismic coupling and decoupling of underground explosions in a salt medium. A series of chemical and nuclear explosions was carried out years ago in salt domes for the Cowboy and the Dribble programs to provide experimental data on seismic coupling for both tamped explosions and explosions in cavities. The Cowboy program consisted of a series of chemical explosions, and the Dribble program consisted of the tamped nuclear Salmon event, the Sterling nuclear event in the Salmon cavity, and an associated site calibration effort. This report presents the results of extensive computer calculations, which are in satisfactory agreement with the experimental data. The calculations were extended to give general results on seismic coupling in salt. The measure of seismic coupling for most of this work was the residual reduced displacement potential (residual RDP). The decoupling associated with a shot in a cavity was expressed as the ratio of the resulting residual RDP to that of an equal-sized tamped shot.

  20. Advances IN Explosive Nuclear Astrophysics

    Science.gov (United States)

    Lotay, Gavin

    2016-09-01

    Breathtaking results from the Planck satellite mission and Hubble space telescope have highlighted the key role modern Astronomy is playing for our understanding of Big Bang Cosmology. However, not so widely publicized is the similar wealth of observational data now available on explosive stellar phenomena, such as X-ray bursts, novae and Supernovae. These astronomical events are responsible for the synthesis of almost all the chemical elements we find on Earth and observe in our Galaxy, as well as energy generation throughout the cosmos. Regrettably, understanding the latest collection of observational data is severely hindered by the current, large uncertainties in the underlying nuclear physics processes that drive such stellar scenarios. In order to resolve this issue, it is becoming increasingly clear that there is a need to explore the unknown properties and reactions of nuclei away from the line of stability. Consequently, state-of-the-art radioactive beam facilities have become terrestrial laboratories for the reproduction of explosive astrophysical events. In this talk, both direct and indirect methods for studying key astrophysical reactions using radioactive beams will be discussed.

  1. Prediction of the wounded and rescue algorithm for emergent events during destruction of Japanese-abandoned chemical weapons(JACW in transportable system

    Directory of Open Access Journals (Sweden)

    Yue-cheng YU

    2011-05-01

    Full Text Available Objective To explore the potential injuries and amount of the wounded during destruction of JACW in transportable system(TSD,thereby to formulate the rational allocation of medical staff at the scene and the scientific algorithm of medical rescue in emergent events.Methods Prediction of the different injuries and amount of the wounded,allocation of the force for emergency medical rescue(EMR,and EMR algorithm were formulated based on the detailed investigation on the types of chemical weapons,working processes and risks during the elimination of JACW in the TSD background.Results The JACW in Nanjing Depository were diphenylcyanarsine,diphenylchloroarsine,chloroacetophenone,mustard gas and lewisite,among them the foremost two were in the majority.Red tanks containing the chemical toxicants are the main types of chemical weapons in warfare,and there were also a few chemical bombs.It was estimated that four to seven workers might be injured in one accident,of them two or three might be seriously injured.The types of injury might be due to intoxication of chemical agent,chemical burn,explosion injury,or combined injuries.The rational allocation of EMR force combined with the scientific rescue algorithm was made according to the information.Conclusions It is of great significance to scientifically allocate the EMR force and formulate algorithm based on the rational prediction of the types and amount of the wounded during elimination process of JACW with TSD in Nanjing.Theory and experience from this research will provide important reference for the same kind of work in other cities later.

  2. High Explosives Research and Development (HERD) Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The purpose is to provide high explosive formulation, chemical analysis, safety and performance testing, processing, X-ray, quality control and loading support for...

  3. Early chemical and ecotoxicological responses of the Varano lagoon (SE Italy) to a flood event.

    Science.gov (United States)

    Fabbrocini, Adele; Cassin, Daniele; Santucci, Angela; Scirocco, Tommaso; Specchiulli, Antonietta; D'Adamo, Raffaele

    2017-10-01

    The effects on coastal lagoons of floods resulting from intense rainfall need to be assessed using a multidisciplinary approach, able to describe in real time the occurrence of changes in sediment quality, anticipating risk situations. In the present study the effectiveness as pre-screening tool of the MOT-test, an innovative bioassay that uses sperm motility as endpoint, has been evaluated; its response has been compared with the sediment chemical characterization, in order to determine the effects of a flood event occurred in the Varano lagoon, a poorly anthropized Mediterranean coastal lagoon. The MOT-test effect percentages ranged from 10% to 30%, fully reflecting data from chemical analyses. Organic pollutants showed concentrations always below the critical levels. The highest metal values were found in the south-eastern area; however, only for few metals (mainly Cd), and in few sites, they reached the limits defined by the sediment quality guidelines; consistently, these sites are located in the area where a higher stressors' impact was expected and the highest MOT-test effect percentages were recorded. In conclusion, even if results exclude the occurrence of serious contamination events as a consequence of the flood, the runoff resulting from the intense rainfall event has caused a pollutant load in the lagoon, consistent with the localization of the main anthropogenic activities in the catchment area. Moreover, preliminary data indicate the validity of the approach adopted for the post-flood quality assessment, proving the usefulness of the MOT-test as early-screening tool in the case of extreme events. Copyright © 2017. Published by Elsevier Inc.

  4. Explosive compositions

    Energy Technology Data Exchange (ETDEWEB)

    Craig, J.F.M.; Falconer, E.L.

    1971-04-13

    A thickening agent for an aqueous slurry explosive composition consists of the combination of a cross-linked galactomannan with psyllium flour in specific proportions. This thickener provides good fluidity and reduced tackiness. (7 claims)

  5. The 1914 Taisho eruption of Sakurajima volcano: stratigraphy and dynamics of the largest explosive event in Japan during the twentieth century

    Science.gov (United States)

    Todde, A.; Cioni, R.; Pistolesi, M.; Geshi, N.; Bonadonna, C.

    2017-10-01

    The 1914 Taisho eruption of Sakurijima volcano was Japan's highest intensity and magnitude eruption of the twentieth century. After a 35-year period of quiescence, the volcano suddenly rewoke a few days before the eruption, when earthquakes began to be felt on Sakurajima Island. The eruption began on January 12, 1914, from two fissures located on opposite sides of the volcano, and was characterized by a complex time evolution and changes in eruptive styles. The eruption began with a subPlinian explosive phase in which two convective columns rose from the two fissures. Both plumes were sustained for at least 2 days. This resulted in deposition of a widely dispersed tephra sequence. After this phase, the eruption evolved to a final, waning phase, shifting toward effusive activity that lasted until April 1914. During the first weeks, effusive activity was also accompanied by ash emission. The complex sequence of events, characterized by contemporaneous explosive and effusive activity, is typical of several recently observed mid-intensity eruptions, such as during the 2011 eruption of Cordón Caulle, Chile. The stratigraphic sequence of the eruptive deposits from the Taisho eruption comprises alternating coarse-to-fine lapilli beds with ash beds dispersed toward the ESE and SE. These deposits can be subdivided into three lapilli-bearing units (Units T1, T2 and T3, which correspond to the subPlinian phase) and one ash-bearing unit (Unit T4, which corresponds to the final ash venting, accompanying the first day/weeks of lava flow activity). Grain size analyses from each unit reveal a marked polymodal distribution generally described by the sum of two or three Gaussian subpopulations. Both the modes and the relative amounts of the coarse subpopulations vary with distance from vent, with those of the fine subpopulation remaining nearly constant. Within the vertical sequence, component analysis shows a progressive increase in lithic fragments, suggesting that conduit

  6. A population-based temporal logic gate for timing and recording chemical events.

    Science.gov (United States)

    Hsiao, Victoria; Hori, Yutaka; Rothemund, Paul Wk; Murray, Richard M

    2016-05-17

    Engineered bacterial sensors have potential applications in human health monitoring, environmental chemical detection, and materials biosynthesis. While such bacterial devices have long been engineered to differentiate between combinations of inputs, their potential to process signal timing and duration has been overlooked. In this work, we present a two-input temporal logic gate that can sense and record the order of the inputs, the timing between inputs, and the duration of input pulses. Our temporal logic gate design relies on unidirectional DNA recombination mediated by bacteriophage integrases to detect and encode sequences of input events. For an E. coli strain engineered to contain our temporal logic gate, we compare predictions of Markov model simulations with laboratory measurements of final population distributions for both step and pulse inputs. Although single cells were engineered to have digital outputs, stochastic noise created heterogeneous single-cell responses that translated into analog population responses. Furthermore, when single-cell genetic states were aggregated into population-level distributions, these distributions contained unique information not encoded in individual cells. Thus, final differentiated sub-populations could be used to deduce order, timing, and duration of transient chemical events. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

  7. Recent advances in medical device triage technologies for chemical, biological, radiological, and nuclear events.

    Science.gov (United States)

    Lansdowne, Krystal; Scully, Christopher G; Galeotti, Loriano; Schwartz, Suzanne; Marcozzi, David; Strauss, David G

    2015-06-01

    In 2010, the US Food and Drug Administration (Silver Spring, Maryland USA) created the Medical Countermeasures Initiative with the mission of development and promoting medical countermeasures that would be needed to protect the nation from identified, high-priority chemical, biological, radiological, or nuclear (CBRN) threats and emerging infectious diseases. The aim of this review was to promote regulatory science research of medical devices and to analyze how the devices can be employed in different CBRN scenarios. Triage in CBRN scenarios presents unique challenges for first responders because the effects of CBRN agents and the clinical presentations of casualties at each triage stage can vary. The uniqueness of a CBRN event can render standard patient monitoring medical device and conventional triage algorithms ineffective. Despite the challenges, there have been recent advances in CBRN triage technology that include: novel technologies; mobile medical applications ("medical apps") for CBRN disasters; electronic triage tags, such as eTriage; diagnostic field devices, such as the Joint Biological Agent Identification System; and decision support systems, such as the Chemical Hazards Emergency Medical Management Intelligent Syndromes Tool (CHEMM-IST). Further research and medical device validation can help to advance prehospital triage technology for CBRN events.

  8. Explosive Yield Estimation using Fourier Amplitude Spectra of Velocity Histories

    Science.gov (United States)

    Steedman, D. W.; Bradley, C. R.

    2016-12-01

    The Source Physics Experiment (SPE) is a series of explosive shots of various size detonated at varying depths in a borehole in jointed granite. The testbed includes an extensive array of accelerometers for measuring the shock environment close-in to the explosive source. One goal of SPE is to develop greater understanding of the explosion phenomenology in all regimes: from near-source, non-linear response to the far-field linear elastic region, and connecting the analyses from the respective regimes. For example, near-field analysis typically involves review of kinematic response (i.e., acceleration, velocity and displacement) in the time domain and looks at various indicators (e.g., peaks, pulse duration) to facilitate comparison among events. Review of far-field data more often is based on study of response in the frequency domain to facilitate comparison of event magnitudes. To try to "bridge the gap" between approaches, we have developed a scaling law for Fourier amplitude spectra of near-field velocity histories that successfully collapses data from a wide range of yields (100 kg to 5000 kg) and range to sensors in jointed granite. Moreover, we show that we can apply this scaling law to data from a new event to accurately estimate the explosive yield of that event. This approach presents a new way of working with near-field data that will be more compatible with traditional methods of analysis of seismic data and should serve to facilitate end-to-end event analysis. The goal is that this new approach to data analysis will eventually result in improved methods for discrimination of event type (i.e., nuclear or chemical explosion, or earthquake) and magnitude.

  9. School Siting Near Industrial Chemical Facilities: Findings from the U.S. Chemical Safety Board's Investigation of the West Fertilizer Explosion

    National Research Council Canada - National Science Library

    Veronica A Tinney; Jerad M Denton; Lucy Sciallo-Tyler; Jerome A Paulson

    2016-01-01

    ...: The goal of this commentary is to illustrate the consequences of siting schools near facilities that store or use hazardous chemicals, and highlight the need for additional regulations to prevent...

  10. Understanding Coatings that Protect Plasmonic Structures for Materials Characterization and Detection and Identification of Chemical, Biological and Explosive Agents

    Science.gov (United States)

    2013-04-11

    the Auger peak, which is consistent with metallic silver and silver sulfide , but not with silver oxide . 10 Figure 9. XPS spectrum from a ten...and Physics. 84th ed.; CRC Press: New York, 2003. 49. Piranha etching consists of using hydrogen peroxide and sulfuric acid, which can be dangerous...transparent and has a very low porosity and high chemical stability. Composite samples of alumina (or silicon oxide ) coating on silver film on a flat

  11. The 2009 paroxysmal explosions at Stromboli (Italy): magma mixing and eruption dynamics

    Science.gov (United States)

    La Felice, Sonia; Landi, Patrizia

    2011-11-01

    Three small-scale paroxysmal explosions (also called major explosions) interrupted ordinary mild Strombolian activity at Stromboli on May 3, November 8 and 24, 2009. Products were largely confined to the summit area, except in the November 24 event, during which coarse pumiceous lapilli reached the coast. Emission of crystal-poor pumice closely mingled with crystal-rich products characterized the three events. The textural and chemical study of minerals and glassy matrices revealed that the two end-members are mingled together physically in the May 3 and November 24 pumice, whereas November 8 products contain heterogeneous glass with intermediate compositions derived from chemical mixing between crystal-rich and crystal-poor magmas. We here discuss the different degrees of interaction between the two magmas in the three explosions in terms of magma dynamics during small-scale paroxysms.

  12. Toxicology of explosives and fireworks in small animals.

    Science.gov (United States)

    Gahagan, Patti; Wismer, Tina

    2012-03-01

    Intoxication with explosives or fireworks in dogs or cats is not common, but serious toxicosis can result from exposure to different types of explosives depending on the chemical class of explosive involved. This article will discuss the different types of materials/chemicals, clinical signs of toxicosis, and their treatment. Despite the complexities of explosives and plethora of different devices currently in use worldwide, the toxic potential is more easily explained by looking at the relatively short list of chemical classes used to produce these materials. This article combines structurally similar explosives into different groups and focuses on the toxicity of the most commonly available explosives.

  13. A computational approach to extinction events in chemical reaction networks with discrete state spaces.

    Science.gov (United States)

    Johnston, Matthew D

    2017-12-01

    Recent work of Johnston et al. has produced sufficient conditions on the structure of a chemical reaction network which guarantee that the corresponding discrete state space system exhibits an extinction event. The conditions consist of a series of systems of equalities and inequalities on the edges of a modified reaction network called a domination-expanded reaction network. In this paper, we present a computational implementation of these conditions written in Python and apply the program on examples drawn from the biochemical literature. We also run the program on 458 models from the European Bioinformatics Institute's BioModels Database and report our results. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Atomistic-scale simulations of the initial chemical events in triacetonetriperoxide (TATP) detonation

    Science.gov (United States)

    van Duin, Adri; Zeiri, Yehuda; Goddard, William

    2005-03-01

    To study the initial chemical events related to the detonation of triacetonetriperoxide (TATP) we have performed a series of molecular dynamics (MD) simulations using the ReaxFF reactive force field [1,2], extended to reproduce the quantumchemical (QM)-derived relative energies of the reactants, products, intermediates and transition states related to the TATP unimolecular decomposition. We find excellent agreement between the reaction products predicted from QM and those observed from ReaxFF unimolecular cookoff simulations. Furthermore, the primary reaction products observed in the unimolecular cookoff simulations match closely with those observed from a TATP-condensed phase cookoff simulation, indicating that unimolecular decomposition dominates TATP-condensed phase initiation. [1] A.C.T. van Duin, S. Dasgupta, F. Lorant and W.A. Goddard (2001), J. Phys. Chem. A 105, 9396-9409.. [2] A. Strachan, A.C.T. van Duin, D. Chakraborty, S. Dasgupta and W.A. Goddard III (2003) Phys. Rev. Letters 91, 09301.

  15. Spatially and chemically resolved source apportionment analysis: Case study of high particulate matter event

    Science.gov (United States)

    Kim, Byeong-Uk; Bae, Changhan; Kim, Hyun Cheol; Kim, Eunhye; Kim, Soontae

    2017-08-01

    This article presents the results of a detailed source apportionment study of the high particulate matter (PM) event in the Seoul Metropolitan Area (SMA), South Korea, during late February 2014. Using the Comprehensive Air Quality Model with Extensions with its Particulate Source Apportionment Technology (CAMx-PSAT), we defined 10 source regions, including five in China, for spatially and chemically resolved analyses. During the event, the spatially averaged PM10 concentration at all PM10 monitors in the SMA was 129 μg/m3, while the PM10 and PM2.5 concentrations at the BulGwang Supersite were 143 μg/m3 and 123 μg/m3, respectively. CAMx-PSAT showed reasonably good PM model performance in both China and the SMA. For February 23-27, CAMx-PSAT estimated that Chinese contributions to the SMA PM10 and PM2.5 were 84.3 μg/m3 and 80.0 μg/m3, respectively, or 64% and 70% of the respective totals, while South Korea's respective domestic contributions were 36.5 μg/m3 and 23.3 μg/m3. We observed that the spatiotemporal pattern of PM constituent concentrations and contributions did not necessarily follow that of total PM10 and PM2.5 concentrations. For example, Beijing-Tianjin-Hebei produced high nitrate concentrations, but the two most-contributing regions to PM in the SMA were the Near Beijing area and South Korea. In addition, we noticed that the relative contributions from each region changed over time. We found that most ammonium mass that neutralized Chinese sulfate mass in the SMA came from South Korean sources, indicating that secondary inorganic aerosol in the SMA, especially ammonium sulfates, during this event resulted from different major precursors originating from different regions.

  16. Intraperitoneal explosion following gastric perforation.

    Science.gov (United States)

    Mansfield, Scott K; Borrowdale, Roderick

    2014-04-01

    The object of this study is to report a rare case of explosion during laparotomy where diathermy ignited intraperitoneal gas from a spontaneous stomach perforation. Fortunately, the patient survived but the surgeon experienced a finger burn. A literature review demonstrates other examples of intraoperative explosion where gastrointestinal gases were the fuel source. Lessons learned from these cases provide recommendations to prevent this potentially lethal event from occurring. Copyright © 2012. Published by Elsevier B.V.

  17. Intraperitoneal explosion following gastric perforation

    Directory of Open Access Journals (Sweden)

    Scott K. Mansfield

    2014-04-01

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

  18. Events

    Directory of Open Access Journals (Sweden)

    Igor V. Karyakin

    2016-02-01

    Full Text Available The 9th ARRCN Symposium 2015 was held during 21st–25th October 2015 at the Novotel Hotel, Chumphon, Thailand, one of the most favored travel destinations in Asia. The 10th ARRCN Symposium 2017 will be held during October 2017 in the Davao, Philippines. International Symposium on the Montagu's Harrier (Circus pygargus «The Montagu's Harrier in Europe. Status. Threats. Protection», organized by the environmental organization «Landesbund für Vogelschutz in Bayern e.V.» (LBV was held on November 20-22, 2015 in Germany. The location of this event was the city of Wurzburg in Bavaria.

  19. Explosives signatures and analysis

    Science.gov (United States)

    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.

  20. Deep water gravity core from the Marsili Basin (Tyrrhenian Sea) records Pleistocenic Holocenic explosive events and instability of the Aeolian Archipelago, (Italy)

    Science.gov (United States)

    Di Roberto, A.; Rosi, M.; Bertagnini, A.; Marani, M. P.; Gamberi, F.; Del Principe, A.

    2008-10-01

    A 4.8 m long gravity core was recovered on a relative topographic high in the northern part of the Marsili Basin (southern Tyrrhenian Sea) at a water depth of 3200 m. The core was taken in order to decipher the sedimentary record of the past volcanic events of the nearby Aeolian arc. A succession of thin (2 cm to 5 cm thick) fine-grained turbidites, mainly of volcaniclastic origin, topped by hemipelagic mud layers and a number of primary tephra layers were recovered by the core. The most prominent turbidite occurs in the lower part of the core at 385 cm. It consists of a 20 cm-thick, thinning-upward, pebble to sand-sized bed. Grain-size analysis and component compositions in the 0.063-0.250 mm size fractions were determined on thirty samples taken from primary tephra beds and the silty-sandy basal part of the volcaniclastic turbidite units. SEM scans and glass fraction chemical analyses were successively carried out on a selection of 17 samples. To aid source correlation and comparison, sub-aerial tephras of the Lower Pollara (Salina, 24 ± 3.6 ka), Gabellotto-Fiumebianco (Lipari, 8.5 or 11.5 ka), Monte Pilato (Lipari, 749 or 580 AD) and Secche di Lazzaro (Stromboli, ~ 5 ka) eruptions were also analyzed with the same procedure. Primary tephra respectively belonging to the eruptions of Lower Pollara, Gabellotto-Fiumebianco and Vesuvius (AP eruptions 3.5 ka-79 AD) were identified in the core at the expected relative stratigraphic depths. Two turbidite beds composed of monogenic glass shards were also identified and interpreted as the remobilisation of primary tephras of Secche di Lazzaro (Stromboli, 5 ka) and Pilato (Lipari, 580 or 749 AD). Tephrochronology results indicate that the cored sequence formed in the last 30 ka suggesting an average sedimentation rate of 0.15-0.17 mm/y. The thick pebbly sandy turbidite unit in the lower part of the core has component and glass composition compatible with the Lower Pollara volcanic sequence of Salina Island. In view of the

  1. The Quiet Explosion

    Science.gov (United States)

    2008-07-01

    . "Since the masses and energies involved are smaller than in every known gamma-ray burst related supernova, we think that the collapse of the star gave rise to a weak jet, and that the presence of the Helium layer made it even more difficult for the jet to remain collimated, so that when it emerged from the stellar surface the signal was weak," says Massimo Della Valle, co-author. "The scenario we propose implies that gamma-ray burst-like inner engine activity exists in all supernovae that form a black hole," adds co-author Stefano Valenti. "As our X-ray and gamma-ray instruments become more advanced, we are slowly uncovering the very diverse properties of stellar explosions," explains Guido Chincarini, co-author and the Principal Investigator of the Italian research on gamma-ray bursts. "The bright gamma-ray bursts were the easiest to discover, and now we are seeing variations on a theme that link these special events to more normal ones." These are however very important discoveries, as they continue to paint a picture of how massive star end their lives, producing dense objects, and injecting new chemical elements back into the gas from which new stars will be formed.

  2. Explosive detection technology

    Science.gov (United States)

    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.

  3. Estimation of body exposure to explosion.

    Science.gov (United States)

    Oliver, William R; Baker, Andrew M; Powell, James D; Cotone, Chris M; Meeker, Jeffrey

    2002-09-01

    An ordnance-disposal expert was killed while disposing of a cache of explosives. The likely position of the body was reconstructed by modeling the explosion as an omnidirectional emission of particles from a model of the explosion site and noting the distribution of particles on a model of a human. The applications and limitations of this method in reconstructing the events and correlation with the injuries noted at autopsy are discussed.

  4. Top five chemicals resulting in injuries from acute chemical incidents—Hazardous Substances Emergency Events Surveillance, nine states, 1999-2008.

    Science.gov (United States)

    Anderson, Ayana R

    2015-04-10

    The Toxic Substances Control Act Chemical Substance Inventory lists >84,000 chemicals used in commerce (http://www.epa.gov/oppt/existingchemicals/pubs/tscainventory/basic.html). With chemicals having a multitude of uses, persons are potentially at risk daily for exposure to chemicals as a result of an acute chemical incident (lasting chemical, exposure can result in morbidity and, in some cases, mortality. 1999-2008. The Hazardous Substances Emergency Events Surveillance (HSEES) system was operated by the Agency for Toxic Substances and Disease Registry during January 1991-September 2009 to collect data that would enable researchers to describe the public health consequences of chemical incidents and to develop activities aimed at reducing the harm from such incidents. This report identifies the top five chemicals that caused injuries in the nine states (Colorado, Iowa, Minnesota, New York, North Carolina, Oregon, Texas, Washington, and Wisconsin) that participated in HSEES during its last 10 full years of data collection (1999-2008). Of the 57,975 incidents that were reported, 54,989 (95%) involved the release of only one chemical. The top five chemicals associated with injury were carbon monoxide (2,364), ammonia (1,153), chlorine (763), hydrochloric acid (326), and sulfuric acid (318). Carbon monoxide and ammonia by far caused the most injuries, deaths, and evacuations. Chlorine, while not in the top 10 chemicals released, was in the top five chemicals associated with injury because of its hazardous properties. Multiple measures can be taken to prevent injuries associated with the top five chemicals. Because many carbon monoxide releases occur in residential settings, use of carbon monoxide detectors can prevent injuries. Substituting chemicals with less lethal alternatives can result in mitigating injuries associated with ammonia. Routine maintenance of equipment and engineering controls can reduce injuries associated with chlorine and sulfuric acid, and proper

  5. Results of joint processing of data on nuclear and chemical explosions recorded on the long-range Quartz profile (Murmansk-Kyzyl)

    Science.gov (United States)

    Pavlenkova, G. A.; Pavlenkova, N. I.

    2008-04-01

    The long-range seismic profile Quartz, measured by the GEON Center (Ministry of Geology of the USSR), crosses a few large geostructures: the East European platform, Timan-Pechora plate, Northern Urals, West Siberian plate (WSP), and Altai. Observations of nuclear and chemical explosions were conducted on the profile. Joint processing of records from sources of both types provided detailed structures of the crust and upper mantle. They have confirmed the known patterns in the structure of these shells of the Earth and revealed new ones. Mountain roots are observed beneath the Urals and Altai, and areas of a higher heat flow are matched by lower velocity zones in the upper mantle. Moreover, it is shown that the Timan-Pechora plate is characterized by a two-layer crust untypical of other young plates of central Eurasia and the upper mantle has the same velocities beneath the ancient East European platform and the young Altai orogen. It is also shown that the vast region including the Timan-Pechora plate, Urals, and WSP is bounded on both sides by deep faults in the upper mantle dipping toward the center of Western Siberia. A few nearly continuous reflectors traceable in the upper mantle are represented by thin-layered heterogeneous beds. The largest horizontal heterogeneity is observed in the upper 100-km layer, often underlain by a lower velocity zone. The asthenosphere, as a layer of lower seismic velocities at the depth of a possible solidus (200 250 km), has not been revealed. The latter is evidently a feature specific to inner parts of the Eurasian continent; in marginal regions, e.g., in Western Europe, the asthenospheric layer is identified almost ubiquitously.

  6. Explosive Pleuritis

    Directory of Open Access Journals (Sweden)

    Jasdeep K Sharma

    2001-01-01

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

  7. Fine particles at a background site in Central France: Chemical compositions, seasonal variations and pollution events.

    Science.gov (United States)

    He, Lin; Chen, Hui; Rangognio, Jérôme; Yahyaoui, Abderrazak; Colin, Patrice; Wang, Jinhe; Daële, Véronique; Mellouki, Abdelwahid

    2018-01-15

    To expand our knowledge of regional fine particles in Central France (Centre-Val de Loire region), a field observation study of PM 2.5 was carried out at Verneuil site (46.81467N, 2.61012E, 180m.a.s.l.) from 2011 to 2014. The mass concentrations of water-soluble inorganic ions (WSIIs), organic carbon (OC), elemental carbon (EC) and biomass burning tracer (Levoglucosan) in PM 2.5 were measured. Annual average PM 2.5 mass concentrations were 11.8, 9.5, 12.6 and 10.2μg·m -3 in 2011, 2012, 2013 and 2014, respectively, three of four higher than the WHO guideline of 10μg·m -3 . Secondary inorganic aerosol (SIA) and organic matter (OM) appeared to be the major components in PM 2.5 in Verneuil, contributing 30.1-41.8% and 36.9-46.3%, respectively. Main chemical species were observed in the following order: winter≥spring>autumn>summer. Backward atmospheric trajectories were performed using Hysplit model and suggested that the PM 2.5 pollutants caused by atmospheric transport were mainly originated from European inland, mainly east to north-east areas. During the observation period, five pollution events were reported and indicated that not only the polluted air masses from central Europe but also the biomass burning from East Europe significantly influenced the air quality in Verneuil site. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Explosive Formulation Pilot Plant

    Data.gov (United States)

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

  9. Underground Explosions

    Science.gov (United States)

    2015-09-09

    is viewed as a result of the propulsion of broken rock mass by explosion gas by-products. The physical model used to recreate the second and the third...period seismographs. Seismologists of the                                                              5  Edinaya  Sistema   Seismicheskih  Nablyudenii...d’explosifs chiniques dans le sable: Programme Dynasol, Centre d’etudes Nucl. De Grenoble Lab. D’applications Speciales de la Physique, Grenoble. 9

  10. Rapid on-site detection of explosives on surfaces by ambient pressure laser desorption and direct inlet single photon ionization or chemical ionization mass spectrometry.

    Science.gov (United States)

    Ehlert, S; Hölzer, J; Rittgen, J; Pütz, M; Schulte-Ladbeck, R; Zimmermann, R

    2013-09-01

    Considering current security issues, powerful tools for detection of security-relevant substances such as traces of explosives and drugs/drug precursors related to clandestine laboratories are required. Especially in the field of detection of explosives and improvised explosive devices, several relevant compounds exhibit a very low vapor pressure. Ambient pressure laser desorption is proposed to make these substances available in the gas phase for the detection by adapted mass spectrometers or in the future with ion-mobility spectrometry as well. In contrast to the state-of-the-art thermal desorption approach, by which the sample surface is probed for explosive traces by a wipe pad being transferred to a thermal desorber unit, by the ambient pressure laser desorption approach presented here, the sample is directly shockwave ablated from the surface. The laser-dispersed molecules are sampled by a heated sniffing capillary located in the vicinity of the ablation spot into the mass analyzer. This approach has the advantage that the target molecules are dispersed more gently than in a thermal desorber unit where the analyte molecules may be decomposed by the thermal intake. In the technical realization, the sampling capillary as well as the laser desorption optics are integrated in the tip of an endoscopic probe or a handheld sampling module. Laboratory as well as field test scenarios were performed, partially in cooperation with the Federal Criminal Police Office (Bundeskriminalamt, BKA, Wiesbaden, Germany), in order to demonstrate the applicability for various explosives, drugs, and drug precursors. In this work, we concentrate on the detection of explosives. A wide range of samples and matrices have been investigated successfully.

  11. Chemical Weapons Improved Response Program (CWIRP) Playbook. Guidelines for Responding to and Managing a Chemical Weapons of Mass Destruction Terrorist Event

    Science.gov (United States)

    2003-12-01

    against standard procedures. This is particularly true during stealth operations or when confronting a suspect. Level A protection also does not...technicians face critical challenges of both agent and explosive hazards when confronted with conventional improvised explosive devices (IED) inside a...care (e.g., dialysis ), victims who may inadvertently contaminate family members, large numbers of deceased, and those psychologically hampered by

  12. Acute chemical incidents surveillance—Hazardous Substances Emergency Events Surveillance, nine states, 1999-2008.

    Science.gov (United States)

    Orr, Maureen F; Wu, Jennifer; Sloop, Sue L

    2015-04-10

    Although they are infrequent, acute chemical incidents (i.e., uncontrolled or illegal release or threatened release of hazardous substances lasting inherently safer design, developing geographic mapping of chemically vulnerable areas, and adopting the principles of green chemistry (design of chemical products and processes that reduce or eliminate the generation of hazardous substances). Because the more populous states such as New York and Texas had the most incidents, areas with high population density should be carefully assessed for preparedness and prevention measures. NTSIP develops estimated incident numbers for states that do not collect data to help with state and national planning. NTSIP also collects more detailed data on chemical incidents with mass casualties. HSEES and NTSIP data can be used by public and environmental health and safety practitioners, worker representatives, emergency planners, preparedness coordinators, industries, emergency responders, and others to prepare for and prevent chemical incidents and injuries.

  13. Chemical Leukoderma Associated with Methylphenidate Transdermal System: Data From the US Food and Drug Administration Adverse Event Reporting System.

    Science.gov (United States)

    Cheng, Carmen; La Grenade, Lois; Diak, Ida-Lina; Brinker, Allen; Levin, Robert L

    2017-01-01

    To identify and characterize cases of chemical leukoderma, an underrecognized adverse event, associated with the methylphenidate transdermal system (MTS) reported to the US Food and Drug Administration Adverse Event Reporting System (FAERS). We searched the Food and Drug Administration Adverse Event Reporting System for reports of chemical leukoderma associated with MTS, received by the Food and Drug Administration from April 6, 2006 to December 23, 2014. We identified 51 cases of chemical leukoderma reported with the use of MTS. The median age was 11 years; 43 cases reported leukoderma at or near the application site only, and 7 reported leukoderma at other parts of the body in addition to the application site; 1 case did not provide enough information to confirm the affected site. The time to onset ranged from 2 months to 4 years after the initiation of MTS. MTS was discontinued in 31 cases. Thirteen patients were prescribed treatment for repigmentation. Three cases reported continued spread of leukoderma after MTS was discontinued. Nineteen cases were diagnosed as vitiligo, including 5 cases reporting histologic features consistent with vitiligo. Leukoderma was persistent in all cases. The median follow-up interval after the discontinuation of MTS in 23 cases was 14 months. As outlined in recent changes to the prescribing information for MTS, health care professionals need to be aware of the potential risk of chemical leukoderma caused by MTS, especially given that chemical leukoderma is often misdiagnosed as idiopathic vitiligo. MTS should be discontinued at the earliest sign of pigment loss and other treatment options considered. Published by Elsevier Inc.

  14. Chemical Events in Oligo(3-methoxythiophene) Coating Solutions and Their Effect on the Goldlike Coating Film Properties.

    Science.gov (United States)

    Takashina, Yumi; Mitogawa, Terumasa; Saito, Kota; Hoshino, Katsuyoshi

    2018-02-19

    Metal-free, metal-like lustrous films may find applications in a variety of fields, and a study of the factors affecting their stability is highly desirable. In particular, chemical events occurring in the coating solutions might affect the supramolecular organization of the films and therefore the metal-like luster. Herein, the chemical events occurring in acetonitrile and nitromethane coating solutions of oligo(3-methoxythiophene) and their effect on the optical properties of the films were investigated by X-ray diffraction, UV-vis absorption, and viscosity measurements. In acetonitrile, the oligomers underwent gradual dedoping with time, but only small changes in viscosity were observed. The solution was applied to a glass plate to yield a dark brown film, which turned into a goldlike lustrous film by rubbing. In nitromethane, the supramolecular structure of the oligomers changed with time from the nonaggregated state to π-dimers and then to π-stacks, and the viscosity increased. The properties of the goldlike films prepared from this solution were greatly affected by this chemical event. Remarkably, the π-dimer solution provided the film with the highest specular reflectance, yellowness, greenness, brightness, and crystallinity.

  15. Intravesical explosion during transurethral electrosurgery.

    Science.gov (United States)

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

    2015-05-01

    Intravesical explosion is a very rare complication of transurethral resection of prostate and transurethral resection of bladder tumour operations. In vitro studies have shown that the gases produced during the procedure could result in a blast once they are mixed with air from the atmosphere. A 79-year-old male experienced an explosion in his bladder while undergoing a transurethral resection of bladder tumour. The case is presented as well as the way that it was treated as an emergency. Precautions of such events are finally suggested. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  16. Forensic analyses of explosion debris from the January 2, 1992 Pd/D{sub 2}O electrochemistry incident at SRI International

    Energy Technology Data Exchange (ETDEWEB)

    Andresen, B.; Whipple, R.; Vandervoort, D.; Grant, P.

    1992-08-15

    The January 2, 1992 explosion in an electrochemistry laboratory at SRI International (SRI) resulted in the death of scientist Andrew Riley, and gained some notoriety due to its association with experimental work in the controversial field of cold fusion research. Selected components of explosion debris were subjected to forensic analyses at LLNL to elucidate potential causes of, or contributing factors to, the explosion. Interrogation of the debris by LLNL encompassed nuclear, chemical, physical, and materials investigations. Nuclear studies for the determination of tritium and neutron-activation products in stainless steel and brass were negative. No evidence of signature species indicative of orthodox nuclear events was detected. The inorganic and particulate analyses were likewise negative with respect to residues of unexpected chemical species. Such target compounds included conventional explosives, accelerants, propellants, or any exceptional industrial chemicals. The GC-MS analyses of trace organic components in the explosion debris provided perhaps the most interesting results obtained at LLNL. Although no evidence of organic explosives, oxidizers, or other unusual compounds was detected, the presence of a hydrocarbon oil in the interior of the electrochemical cell was established. It is likely that its source was lubricating fluid from the machining of the metal cell components. If residues of organic oils are present during electrolysis experiments, the potential exists for an explosive reaction in the increasingly enriched oxygen atmosphere within the headspace of a metal cell.

  17. Supernova explosions

    CERN Document Server

    Branch, David

    2017-01-01

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

  18. How Unique is Any Given Seismogram? - Exploring Correlation Methods to Identify Explosions

    Science.gov (United States)

    Walter, W. R.; Dodge, D. A.; Ford, S. R.; Pyle, M. L.; Hauk, T. F.

    2015-12-01

    As with conventional wisdom about snowflakes, we would expect it unlikely that any two broadband seismograms would ever be exactly identical. However depending upon the resolution of our comparison metric, we do expect, and often find, bandpassed seismograms that correlate to very high levels (>0.99). In fact regional (e.g. Schaff and Richards, 2011) and global investigations (e.g. Dodge and Walter, 2015) find large numbers of highly correlated seismograms. Decreasing computational costs are increasing the tremendous potential for correlation in lowering detection, location and identification thresholds for explosion monitoring (e.g. Schaff et al., 2012, Gibbons and Ringdal, 2012; Zhang and Wen, 2015). We have shown in the case of Source Physics Experiment (SPE) chemical explosions, templates at local and near regional stations can detect, locate and identify very small explosions, which might be applied to monitoring active test sites (Ford and Walter, 2015). In terms of elastic theory, seismograms are the convolution between source and Green function terms. Thus high correlation implies similar sources, closely located. How do we quantify this physically? For example it is well known that as the template event and target events are increasingly separated spatially, their correlation diminishes, as the difference in the Green function between the two events grows larger. This is related to the event separation in terms of wavelength, the heterogeneity of the Earth structure, and the time-bandwidth of the correlation parameters used, but this has not been well quantified. We are using the historic dataset of nuclear explosions in southern Nevada to explore empirically where and how well these events correlate as a function of location, depth, size, time-bandwidth and other parameters. A goal is to develop more meaningful and physical metrics that go beyond the correlation coefficient and can be applied to explosion monitoring problems, particularly event

  19. Coulomb explosion of polycyclic aromatic hydrocarbons induced by heavy cosmic rays: carbon chains production rates

    OpenAIRE

    Chabot, Marin; Béroff, Karine; Dartois, Emmanuel; Pino, Thomas; Godard, Marie

    2017-01-01

    Cosmic Rays (CR) process the matter of the Interstellar Medium. Such energetic processing not only modifies the interstellar matter but also injects chemical species in the gas phase. In this work, we study the effect of the CR on the astrophysical polycyclic aromatic hydrocarbons (PAH). For events in which many electrons are stripped out from the PAH by interaction with a heavy cosmic ray particle, coulomb explosion takes place and carbon chains are produced. The fragments production rates o...

  20. Shaping a novel security approach in chemical industrial clusters to prevent large-scale domino events

    NARCIS (Netherlands)

    Reniers, Genserik L L; Dullaert, Wout; Soudan, Karel

    2009-01-01

    Two aspects are important when it comes to guaranteeing an effective and efficient security policy in a chemical industrial cluster. The first issue involves obtaining an acceptable level of collaboration between the different enterprises forming the cluster. The second topic is to ensure that an

  1. Understanding vented gas explosions

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-12-31

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

  2. Independence day explosion on lovers key.

    Science.gov (United States)

    Harding, Brett A; Wolf, Barbara C

    2007-09-01

    The display of fireworks is a popular holiday celebration in the United States. Because injuries due to recreational fireworks-related explosions among private consumers are relatively common, the sale of fireworks is regulated by the federal government and is also limited by state and local laws. In contrast, because fireworks display companies are under tight safety regulations, explosions in the professional pyrotechnics industry are uncommon occurrences, and the literature contains rare reports of injuries and fatalities resulting from such explosions. We report the 2003 Fourth of July commercial fireworks explosion on Lovers Key in southwest Florida that resulted in five fatalities. Events occurring during the investigation of the scene of this explosion illustrate the unique considerations and hazards for medicolegal death investigators, law enforcement and other investigative agencies. Additionally, this case demonstrates unusual aspects of the postmortem examinations performed on victims of fireworks-related incidents.

  3. Sacrificial fragmentation and superheated foaming trigger of explosive volcanism

    Science.gov (United States)

    Lavallée, Yan; Cimarelli, Corrado; Hornby, Adrian; Johnson, Jeffrey; Kendrick, Jackie; von Aulock, Felix; Wadsworth, Fabian; Rhodes, Emma; Kennedy, Ben; Andrews, Benjamin; Chigna, Gustavo; Dingwell, Donald

    2015-04-01

    The most common occurrence of volcanic activity is at lava domes. Active domes tend to experience near sudden episodes of gas-and-ash explosion on a daily basis and sometimes several times per day. This unpredictable behaviour is an expression of magma forced to undergo fragmentation due to gas overpressure. Here, Examination of dome activity reveals that gas-and-ash explosions are concordant with inflation/deflation cycles that are faster than during simple outgassing episodes. Although frequent, these gas-and-ash explosions usually leave the dome intact as strain is almost entirely accommodated along repeatedly activated marginal faults, as seen at Santiaguito, Guatemala. We present petrological evidence that gas-and-ash eruptions are the product of fragmentation due to "superheated foaming" along fault zones. Textural analysis reveals chemically heterogeneous melt filaments emerging from crystals in the ash generated by fragmentation in these events. The same texture is observed in high-velocity, rotary-shear experiments on Santiaguito dome lava. The frictional melting is experimentally generated after mere centimetres of slip of these lavas, and yields foaming of the interstitial melt adjacent to the slip zone. Rapid and intense local frictional heating can explain both the foaming and the fragmentation cycles of these magmas. Gas-and-ash explosions exhibited in the dome at Santiaguito are hence controlled by the inevitable frictional heating which results from tenacious strain localisation, whereby lava is "sacrificially" fragmented along faults in order to preserve the bulk of the dome. We discuss how this new fragmentation trigger may underline the most common type of explosive activity.

  4. Analysis of Simplified Hydrogen and Dust Explosion in the Vacuum Vessel Accident using MELCOR Code

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Soo Min; Moon, Sung Bo; Bang, In Cheol [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The failure of the confinement barriers inside a penetration line between the VV and a port cell initiates the accident. Air ingress in VV results in formation of hydrogen/air explosive mixture and further explosion. Hydrogen explosion is assumed to trigger a dust explosion which leads to a large pressure peak creating a connection between VV and NBI Cell. Any other components related to the accident other than VV, suppression tank (ST), port cell, NBI Cell and Gallery are ignored in the analysis. Additional Free volume is assumed connected to the VV to simulate hydrogen/dust explosions. Figure 1 presents schematics of modeling of thermal-hydraulic analysis used in the accident analysis. For ITER design, three volumes of accident analysis report (AAR) presents analysis of selected postulated events important in ITER safety studies including hypothetical events. MELCOR 1.8.2 code was chosen as one of the several codes to perform ITER safety analysis because it models wide range of physical phenomena such as thermal-hydraulics, heat transfer, and other phenomena including aerosol physics. MELCOR can also predict structural temperatures using energy produced by radioactive heat or chemical reactions. Analysis has shown that hydrogen/dust explosion damaged the VV confinement barriers transporting dust from VV to the port cell, NBI cell and other penetrating lines. Unlike the accident analysis performed in the accident analysis report (AAR), the radioactive material was released into the environment shortly after the event. Simplified accident analysis was performed in attempt to perform fast safety analysis, however, multiple components and initial conditions not under consideration caused significant difference from the AAR analysis results.

  5. Nucleosynthesis in stellar explosions

    Energy Technology Data Exchange (ETDEWEB)

    Woosley, S.E.; Axelrod, T.S.; Weaver, T.A.

    1983-01-01

    The final evolution and explosion of stars from 10 M/sub solar/ to 10/sup 6/ M/sub solar/ are reviewed with emphasis on factors affecting the expected nucleosynthesis. We order our paper in a sequence of decreasing mass. If, as many suspect, the stellar birth function was peaked towards larger masses at earlier times (see e.g., Silk 1977; but also see Palla, Salpeter, and Stahler 1983), this sequence of masses might also be regarded as a temporal sequence. At each stage of Galactic chemical evolution stars form from the ashes of preceding generations which typically had greater mass. A wide variety of Type I supernova models, most based upon accreting white dwarf stars, are also explored using the expected light curves, spectra, and nucleosynthesis as diagnostics. No clearly favored Type I model emerges that is capable of simultaneously satisfying all three constraints.

  6. DOE TMD transportation training module 14 transportation of explosives

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, R.L. Jr.

    1994-07-01

    The Department of Energy Transportation Management Division has developed training module 14, entitled {open_quotes}Transportation of Explosives{close_quotes} to compliment the basic {open_quotes}core ten{close_quotes} training modules of the Hazardous Materials Modular Training Program. The purpose of this training module is to increase awareness of the Department of Transportation (DOT) requirements concerning the packaging and transportation of explosives. Topics covered in module 14 include the classification of explosives, approval and registration of explosives, packaging requirements, hazard communication requirements, separation and segregation compatibility requirements, loading and unloading operations, as well as safety measures required in the event of a vehicle accident involving explosives.

  7. Inspection tester for explosives

    Science.gov (United States)

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

    2007-11-13

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

  8. On the Violence of High Explosive Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Tarver, C M; Chidester, S K

    2004-02-09

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

  9. PINS Testing and Modification for Explosive Identification

    Energy Technology Data Exchange (ETDEWEB)

    E.H. Seabury; A.J. Caffrey

    2011-09-01

    The INL's Portable Isotopic Neutron Spectroscopy System (PINS)1 non-intrusively identifies the chemical fill of munitions and sealed containers. PINS is used routinely by the U.S. Army, the Defense Threat Reduction Agency, and foreign military units to determine the contents of munitions and other containers suspected to contain explosives, smoke-generating chemicals, and chemical warfare agents such as mustard and nerve gas. The objects assayed with PINS range from softball-sized M139 chemical bomblets to 200 gallon DOT 500X ton containers. INL had previously examined2 the feasibility of using a similar system for the identification of explosives, and based on this proof-of-principle test, the development of a dedicated system for the identification of explosives in an improvised nuclear device appears entirely feasible. INL has been tasked by NNSA NA-42 Render Safe Research and Development with the development of such a system.

  10. 75 FR 5545 - Explosives

    Science.gov (United States)

    2010-02-03

    ... for classifying, labeling, and providing safety data sheets for explosives. By withdrawing this.... OSHA-S031-2006-0665 and OSHA-S-031)] RIN 1218-AC09 Explosives AGENCY: Occupational Safety and Health... the rulemaking to amend its Explosives and Blasting Agents Standard at 29 CFR 1910.109. OSHA is taking...

  11. Dynamics of explosive degassing of magma: Observations of fragmenting two-phase flows

    Science.gov (United States)

    Mader, H. M.; Phillips, J. C.; Sparks, R. S. J.; Sturtevant, B.

    1996-03-01

    Liquid explosions, generated by rapid degassing of strongly supersaturated liquids, have been investigated in the laboratory with a view to understanding the basic physical processes operating during bubble nucleation and growth and the subsequent behavior of the expanding two-phase flow. Experiments are carried out in a shock tube and are monitored by high-speed photography and pressure transducers. Theoretical CO2 supersaturations up to 455 times the ambient saturation concentration are generated by a chemical reaction; K2CO3 solution is suddenly injected into an excess of HCl solution in such a way as to mix the two solutions rapidly. Immediately after the injection event, a bubble nucleation delay of a few milliseconds is followed by rapid nucleation and explosive expansion of CO2 bubbles forming a highly heterogeneous foam. Enhanced diffusion due to advection in the flow coupled with continuous mixing of the reactants, and hence on-going bubble nucleation after injection, generates an increasingly accelerating flow until the reactants become depleted at peak accelerations of around 150 g and velocities of about 15 ms-1. Stretching of the accelerating two-phase mixture enhances the mixing. Liberation of CO2 vapor is spatially inhomogeneous leading to ductile fragmentation occurring throughout the flow in regions of greatest gas release as the consequence of the collision and stretching of fluid streams. The violence of the eruptions is controlled by using different concentrations of the HCl and K2CO3 solutions, which alters the CO2 supersaturation and yield and also the efficiency of the mixing process. Peak acceleration is proportional to theoretical supersaturation. Pressure measurements at the base of the shock tube show an initial nucleation delay and a pressure pulse related to the onset of explosive bubble formation. These chemically induced explosions differ from liquid explosions created in other experiments. In explosions caused by sudden

  12. Nuclear explosives testing readiness evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Valk, T.C.

    1993-09-01

    This readiness evaluation considers hole selection and characterization, verification, containment issues, nuclear explosive safety studies, test authorities, event operations planning, canister-rack preparation, site preparation, diagnostic equipment setup, device assembly facilities and processes, device delivery and insertion, emplacement, stemming, control room activities, readiness briefing, arming and firing, test execution, emergency response and reentry, and post event analysis to include device diagnostics, nuclear chemistry, and containment. This survey concludes that the LLNL program and its supporting contractors could execute an event within six months of notification, and a second event within the following six months, given the NET group`s evaluation and the following three restraints: (1) FY94 (and subsequent year) funding is essentially constant with FY93, (2) Preliminary work for the initial event is completed to the historical sic months status, (3) Critical personnel, currently working in dual use technologies, would be recallable as needed.

  13. Youngest Stellar Explosion in Our Galaxy Discovered

    Science.gov (United States)

    2008-05-01

    supernova explosions with optical telescopes across half of the Universe, but when they're in this murk, we can miss them in our own cosmic back yard," Reynolds said. "Fortunately, the expanding gas cloud from the explosion shines brightly in radio waves and X-rays for thousands of years. X-ray and radio telescopes can see through all that obscuration and show us what we've been missing," he added. Because of the obscuration, no one could have seen the original explosion 140 years ago. The astronomers are reporting their results in papers published in the Astrophysical Journal Letters and Monthly Notices of the Royal Astronomical Society. Background Information: Supernova Explosions Supernova explosions are the violent death throes of stars. These explosions release in one event as much energy as is being released by all the rest of the stars in a galaxy -- typically 100 billion or so. Supernovae seen in other galaxies can outshine the rest of their galaxy for days. The supernovae that have occurred in our own Galaxy and were not obscured by the gas and dust that obscured G1.9+0.3 have often provided a spectacular sight. Historical records indicate that ancient astronomers noted supernova explosions at least as early as A.D. 393, and probably earlier. The pre-telescopic astronomers Tycho Brahe and Johannes Kepler made extensive observations of supernovae in 1572 and 1604. Chinese astronomers noted that a supernova in 1054 was bright enough to be seen in the daytime. A supernova in 1006 remained visible for two years. Supernovae that result from the deaths of stars much more massive than the Sun enrich the galaxy with chemical elements that are produced in the cores of those stars before they explode. The heavy elements, such as carbon, oxygen, iron, siicon and calcium, that make up planets and their inhabitants were made available by supernova explosions. In addition to enriching the material between stars with heavy elements, supernovae stir up that material through the

  14. Filamentary structure in chemical tracer distributions near the subtropical jet following a wave breaking event

    Directory of Open Access Journals (Sweden)

    J. Ungermann

    2013-10-01

    Full Text Available This paper presents a set of observations and analyses of trace gas cross sections in the extratropical upper troposphere/lower stratosphere (UTLS. The spatially highly resolved (≈0.5 km vertically and 12.5 km horizontally cross sections of ozone (O3, nitric acid (HNO3, and peroxyacetyl nitrate (PAN, retrieved from the measurements of the CRISTA-NF infrared limb sounder flown on the Russian M55-Geophysica, revealed intricate layer structures in the region of the subtropical tropopause break. The chemical structure in this region shows an intertwined stratosphere and troposphere. The observed filaments in all discussed trace gases are of a spatial scale of less than 0.8 km vertically and about 200 km horizontally across the jet stream. Backward trajectory calculations confirm that the observed filaments are the result of a breaking Rossby wave in the preceding days. An analysis of the trace gas relationships between PAN and O3 identifies four distinct groups of air mass: polluted subtropical tropospheric air, clean tropical upper-tropospheric air, the lowermost stratospheric air, and air from the deep stratosphere. The tracer relationships further allow the identification of tropospheric, stratospheric, and the transitional air mass made of a mixture of UT and LS air. Mapping of these air mass types onto the geo-spatial location in the cross sections reveals a highly structured extratropical transition layer (ExTL. Finally, the ratio between the measured reactive nitrogen species (HNO3 + PAN + ClONO2 and O3 is analysed to estimate the influence of tropospheric pollution on the extratropical UTLS. In combination, these diagnostics provide the first example of a multi-species two-dimensional picture of the inhomogeneous distribution of chemical species within the UTLS region. Since Rossby wave breaking occurs frequently in the region of the tropopause break, these observed fine-scale filaments are likely ubiquitous in the region. The

  15. Geology of the Vilama caldera: A new interpretation of a large-scale explosive event in the Central Andean plateau during the Upper Miocene

    Science.gov (United States)

    Soler, M. M.; Caffe, P. J.; Coira, B. L.; Onoe, A. T.; Kay, S. Mahlburg

    2007-07-01

    The Vilama caldera is one of the very large-volume volcanic structures that formed during the ignimbrite flare-up that lasted from 10 Ma to 4 Ma on the central Andean plateau. Formerly, the Vilama structure was interpreted as a 65 × 40 km wide caldera with a two stage evolution. New field correlations, petrographical, geochemical and geochronological data lead to a substantially larger reinterpreted Vilama ignimbrite, whose outcrops cover more than 4000 km 2. New and existing K/Ar and Ar/Ar dating shows that the dacitic Vilama ignimbrite erupted from the Vilama caldera at 8.4-8.5 Ma. The ignimbrite can be divided into extracaldera outflow and intracaldera deposits. The outflow has a mean thickness of ˜ 40 m and is separated into a restricted valley-ponded lower cooling unit, and a laterally extensive low aspect ratio upper cooling unit. The Vilama caldera, which is roughly rectangular (35-40 km × 15-18 km) in shape and has central coordinates of 22°24' S and 66°57' W, is considered to have formed in a single-stage collapse event. As the topographic rim is only seen on the western side, the extent of collapse and geometry of the caldera are incompletely known and inferred from indirect data. Possible collapse geometries include a slightly asymmetric single-block subsidence and non-chaotic multiple-block collapse. Estimated erupted volumes range from ˜ 1800 to 1200 km 3, or 1400 to 1000 km 3 in dense rock equivalents. The properties of the Vilama ignimbrite which include a crystal-rich and pumice-poor nature, a high degree of welding and induration and a prodigious volume, suggest that an external drive, rather than volatile overpressures, controlled and maintained the eruption. The best candidate is caldera subsidence triggered by the instability of a magma chamber roof above a batholith-scale magma body. Transtensive/distensive tectonic stresses resulted in the northwest elongation of the magma chamber and/or influenced the roughly rectangular

  16. Simulating thermal explosion of RDX-based explosives: Model comparison with experiment

    Energy Technology Data Exchange (ETDEWEB)

    Yoh, J J; McClelland, M A; Maienschein, J L; Wardell, J F; Tarver, C M

    2004-10-11

    We compare two-dimensional model results with measurements for the thermal, chemical and mechanical behavior in a thermal explosion experiment. Confined high explosives are heated at a rate of 1 C per hour until an explosion is observed. The heating, ignition, and deflagration phases are modeled using an Arbitrarily Lagrangian-Eulerian code (ALE3D) that can handle a wide range of time scales that vary from a structural to a dynamic hydro time scale. During the pre-ignition phase, quasi-static mechanics and diffusive thermal transfer from a heat source to the HE are coupled with the finite chemical reactions that include both endothermic and exothermic processes. Once the HE ignites, a hydro dynamic calculation is performed as a burn front propagates through the HE. Two RDX-based explosives, C-4 and PBXN-109, are considered, whose chemical-thermal-mechanical models are constructed based on measurements of thermal and mechanical properties along with small scale thermal explosion measurements. The simulated dynamic response of HE confinement during the explosive phase is compared to measurements in large scale thermal explosion tests. The explosion temperatures for both HE's are predicted to within 5 C. Calculated and measured wall strains provide an indication of vessel pressurization during the heating phase and violence during the explosive phase. During the heating phase, simulated wall strains provide only an approximate representation of measured values indicating a better numerical treatment is needed to provide accurate results. The results also show that more numerical accuracy is needed for vessels with lesser confinement strength. For PBXN-109, the measured wall strains during the explosion are well represented by the ALE3D calculations.

  17. Methamphetamine laboratory-related burns in Western Australia--why the explosion?

    Science.gov (United States)

    O'Neill, Tomas B; Rawlins, J M; Rea, S; Wood, F M

    2011-09-01

    With increasing numbers of illicit drug users in both urban and rural communities, users and producers are becoming increasingly enterprising in their sourcing of mind altering drugs. An example of this is the 'amateur' production of methamphetamine in domestic dwellings. We describe the mechanism of burn seen in methamphetamine production, the pattern of clinical injury, and the difficulties in treating these patients. A 12 month retrospective study of five patient groups presenting to our burn service with injuries following methamphetamine laboratory explosion. Out of five patient groups we have treated 9 individual patients (with one patient presenting on two different occasions) with burns following methamphetamine laboratory explosion. All patients were male and required hospital admission. The cause of the explosive injury was initially reported as barbeque or oven related, assault, or accident in all patients. Two patients (in separate events) required intubation for associated inhalation injury. Burn size varied from 1% to 40% BSA. 7 patients required surgical debridement and skin grafting. Injury type was thermal and chemical. All patients had difficult follow-up due to low levels of clinic attendance. Methamphetamine laboratory explosion burns are difficult injuries from the start. Invariably the true circumstances surrounding the injury are not clear, and clinicians should be suspicious of a meth lab explosion in suspect individuals with burns plus airway injury. Patient management is complex and often requires substantial analgesic and anxiolytic medication in conjunction with clinical psychology and psychiatry as an inpatient. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.

  18. Water Chemical Change in a Storm Event in a Karst River

    Science.gov (United States)

    Shi, Y.

    2016-12-01

    Rainfall (P), discharge (Q), water temperature, pH, and specific electrical conductivity (EC) of the karst surface river(Li river) in Guangxi Province, Southwest China were continuously monitored during a period 50 hours from 7 to 9 in April, 2015 using ODEON high-resolution multi-parameter data loggers. In addition, HCO3- and calcium concentrations were titrated in the field using portable test kit. Water samples were collected at 2-h sampling interval, which were analyzed in the laboratory for major parameters. The primary goal of this study is to assess evolution process of river water which was affected by both natural and human activity during a storm event in study catchment. Results show that 1)the main anion and cation was HCO3- and Ca2+ respectively in Li river. Besides, the variation of HCO3- and Ca2+ are closely related to the calcite saturation index (SIc), partial pressure of CO2 (Pco2) and conductivity (EC) in different hydrology processes, 2) The significantly linear correlation between total suspended material (TSM) concentration and discharge indicated that the TSM concentration was controlled by the intensity of mechanical erosion in the watershed. However, there were two peak values during the flood period, which might be caused by the relatively distributed sample sites. 3) The weak positive correlation between DOC concentration and discharge indicated that DOC was not only related to rainfall and hydrology process, but also affected by the biogeochemical process, such as the adsorption by the suspended solids in the river, biological degradation and regeneration and so on.

  19. Analogies Between Digital Radio and Chemical Orthogonality as a Method for Enhanced Analysis of Molecular Recognition Events

    Directory of Open Access Journals (Sweden)

    Sang-Hun Lee

    2008-02-01

    Full Text Available Acoustic wave biosensors are a real-time, label-free biosensor technology, which have been exploited for the detection of proteins and cells. One of the conventional biosensor approaches involves the immobilization of a monolayer of antibodies onto the surface of the acoustic wave device for the detection of a specific analyte. The method described within includes at least two immobilizations of two different antibodies onto the surfaces of two separate acoustic wave devices for the detection of several analogous analytes. The chemical specificity of the molecular recognition event is achieved by virtue of the extremely high (nM to pM binding affinity between the antibody and its antigen. In a standard ELISA (Enzyme-Linked ImmunoSorbent Assay test, there are multiple steps and the end result is a measure of what is bound so tightly that it does not wash away easily. The fact that this “gold standard” is very much not real time, masks the dance that is the molecular recognition event. X-Ray Crystallographer, Ian Wilson, demonstrated more than a decade ago that antibodies undergo conformational change during a binding event[1, 2]. Further, it is known in the arena of immunochemistry that some antibodies exhibit significant cross-reactivity and this is widely termed antibody promiscuity. A third piece of the puzzle that we will exploit in our system of acoustic wave biosensors is the notion of chemical orthogonality. These three biochemical constructs, the dance, antibody promiscuity and chemical orthogonality will be combined in this paper with the notions of Int. J. Mol. Sci. 2008, 9 155 in-phase (I and quadrature (Q signals from digital radio to manifest an approach to molecular recognition that allows a level of discrimination and analysis unobtainable without the aggregate. As an example we present experimental data on the detection of TNT, RDX, C4, ammonium nitrate and musk oil from a system of antibody-coated acoustic

  20. Size-resolved aerosol chemical analysis of extreme haze pollution events during early 2013 in urban Beijing, China.

    Science.gov (United States)

    Tian, Shili; Pan, Yuepeng; Liu, Zirui; Wen, Tianxue; Wang, Yuesi

    2014-08-30

    Using size-resolved filter sampling and chemical characterization, high concentrations of water-soluble ions, carbonaceous species and heavy metals were found in both fine (PM2.1) and coarse (PM2.1-9) particles in Beijing during haze events in early 2013. Even on clear days, average mass concentration of submicron particles (PM1.1) was several times higher than that previously measured in most of abroad urban areas. A high concentration of particulate matter on haze days weakens the incident solar radiation, which reduces the generation rate of secondary organic carbon in PM1.1. We show that the peak mass concentration of particles shifted from 0.43-0.65μm on clear days to 0.65-1.1μm on lightly polluted days and to 1.1-2.1μm on heavily polluted days. The peak shifts were also found for the following species: organic carbon, elemental carbon, NH4(+), SO4(2-), NO3(-), K, Cu, Zn, Cd and Pb. Our findings demonstrate that secondary inorganic aerosols (36%) and organic matter (26%) dominated the fine particle mass on heavily polluted days, while their contribution reduced to 29% and 18%, respectively, on clear days. Besides fine particles, anthropogenic chemical species also substantially accumulated in the coarse mode, which suggests that particles with aerodynamic diameter larger than 2.1μm cannot be neglected during severe haze events. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. PM2.5in the Yangtze River Delta, China: Chemical compositions, seasonal variations, and regional pollution events.

    Science.gov (United States)

    Ming, Lili; Jin, Ling; Li, Jun; Fu, Pingqing; Yang, Wenyi; Liu, Di; Zhang, Gan; Wang, Zifa; Li, Xiangdong

    2017-04-01

    Fine particle (PM 2.5 ) samples were collected simultaneously at three urban sites (Shanghai, Nanjing, and Hangzhou) and one rural site near Ningbo in the Yangtze River Delta (YRD) region, China, on a weekly basis from September 2013 to August 2014. In addition, high-frequency daily sampling was conducted in Shanghai and Nanjing for one month during each season. Severe regional PM 2.5 pollution episodes were frequently observed in the YRD, with annual mean concentrations of 94.6 ± 55.9, 97.8 ± 40.5, 134 ± 54.3, and 94.0 ± 57.6 μg m -3 in Shanghai, Nanjing, Hangzhou, and Ningbo, respectively. The concentrations of PM 2.5 and ambient trace metals at the four sites showed clear seasonal trends, with higher concentrations in winter and lower concentrations in summer. In Shanghai, similar seasonal patterns were found for organic carbon (OC), elemental carbon (EC), and water-soluble inorganic ions (K + , NH 4 + , Cl - , NO 3 - , and SO 4 2- ). Air mass backward trajectory and potential source contribution function (PSCF) analyses implied that areas of central and northern China contributed significantly to the concentration and chemical compositions of PM 2.5 in Shanghai during winter. Three heavy pollution events in Shanghai were observed during autumn and winter. The modelling results of the Nested Air Quality Prediction Modeling System (NAQPMS) showed the sources and transport of PM 2.5 in the YRD during the three pollution processes. The contribution of secondary species (SOC, NH 4 + , NO 3 - , and SO 4 2- ) in pollution event (PE) periods was much higher than in BPE (before pollution event) and APE (after pollution event) periods, suggesting the importance of secondary aerosol formation during the three pollution events. Furthermore, the bioavailability of Cu, and Zn in the wintertime PM 2.5 samples from Shanghai was much higher during the pollution days than during the non-pollution days. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. New Mix Explosives for Explosive Welding

    Science.gov (United States)

    Andreevskikh, Leonid

    2011-06-01

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

  3. Fast Chromatographic Method for Explosive Profiling

    Directory of Open Access Journals (Sweden)

    Pierre-Hugues Stefanuto

    2015-05-01

    Full Text Available Security control is becoming a major global issue in strategic locations, such as airports, official buildings, and transit stations. The agencies responsible for public security need powerful and sensitive tools to detect warfare agents and explosives. Volatile signature detection is one of the fastest and easiest ways to achieve this task. However, explosive chemicals have low volatility making their detection challenging. In this research, we developed and evaluated fast chromatographic methods to improve the characterization of volatile signatures from explosives samples. The headspace of explosives was sampled with solid phase micro-extraction fiber (SPME. Following this step, classical gas chromatography (GC and comprehensive two-dimensional GC (GC×GC were used for analysis. A fast GC approach allows the elution temperature of each analyte to be decreased, resulting in decreased thermal degradation of sensitive compounds (e.g., nitro explosives. Using fast GC×GC, the limit of detection is further decreased based on the cryo-focusing effect of the modulator. Sampling of explosives and chromatographic separation were optimized, and the methods then applied to commercial explosives samples. Implementation of fast GC methods will be valuable in the future for defense and security forensics applications.

  4. Imaging an Explosion with a 1000 Sensors: The SPE Large N Array

    Science.gov (United States)

    Mellors, R. J.; Snelson, C. M.; Pitarka, A.; Chen, T.; Matzel, E.; Walter, W. R.

    2016-12-01

    The Source Physics Experiment (SPE) is a series of heavily instrumented chemical explosions at the Nevada National Security Site (NNSS) designed to improve understanding of seismic wave generation and propagation from explosions. On April 26, 2016, a 5000 kg TNT equivalent chemical explosion (SPE5) was detonated at a depth of 76.5 meters (center) in a stemmed hole. The explosion was recorded by a temporary deployment of 1000 geophones with a variable spacing from 25 to 100 m and consisting of 500 vertical and 500 three-component 5 Hz geophones. Distance from ground zero to the geophones range from 400 to 3000 m. The shot is located in a weathered granite intrusive body surrounded by volcanic tuffs, Paleozoic carbonates, and alluvium. The purpose is to map the 3D waveform propagation with emphasis on the generation of S waves and to compare with synthetics. A focus is the transition from the granite to alluvium that occurs at a steeply dipping strike-slip fault. A secondary goal is to record ambient noise data for tomography. An active source experiment using a weight drop was also conducted. Data recovery was good, with approximately 95% of data recovered from the shot and up to 99% in the following weeks. In addition to the SPE5 shot, a variety of local earthquakes and teleseismic events were recorded. Prepared by LLNL under Contract DE-AC52-07NA27344.

  5. Observing a Chemically and/or Climatically Important Volcano: Facilitating Rapid Response to an Unanticipated yet Inevitable Event

    Science.gov (United States)

    Kaye, J. A.

    2015-12-01

    A large volcanic event has the potential to influence the chemical and/or physical state of the Earth's atmosphere in a significant way. In particular, changes in the trace constituent and/or particulate composition of the stratosphere, as well as the temperature distribution of the troposphere and stratosphere can both take place (and persist over a period of time), as has been observed in several eruptions in recent years (e.g., the Mount Pinatubo eruption in 1991). Characterizing the impacts of these eruptions and predicting their impacts on the evolution of the atmosphere requires observations of gas and particle distributions over time period from as soon after eruption as possible to the longer time period over which the Earth system is affected. This characterization may make use of observation capabilities from ongoing surface-based and existing satellite-based observing systems, and can also benefit significantly from focused airborne campaigns that make use of both in situ and remote sensing instrumentation. This presentation will review the relevant surface- and space-based observing capability operated by NASA in the broader context of the global observing capabilities of the international community, and and will discuss potential approaches to airborne campaigns (platforms, sensors, systems, logistical consideration) that would provide the data most useful for both characterization and forecasting of both the chemical and climatic forcing and impacts associated with the eruption.

  6. A proposal for field-level medical assistance in an international humanitarian response to chemical, biological, radiological or nuclear events.

    Science.gov (United States)

    Malich, Gregor; Coupland, Robin; Donnelly, Steve; Baker, David

    2013-10-01

    A capacity for field-level medical assistance for people exposed to chemical, biological, radiological or nuclear (CBRN) agents or medical support for people potentially exposed to these agents is intrinsically linked to the overall risk management approach adopted by the International Committee of the Red Cross (ICRC) for an international humanitarian response to a CBRN event. This medical assistance articulates: ▸the characteristics of the agent concerned (if known) ▸the need for immediate care particularly for people exposed to agents with high toxicity and short latency ▸the imperative for those responding to be protected from exposure to the same agents. This article proposes two distinct capacities for medical assistance--CBRN field medical care and CBRN first aid--that take the above into account and the realities of a CBRN event including the likelihood that qualified medical staff may not be present with the right equipment. These capacities are equally pertinent whether in support of ICRC staff or for assistance of victims of a CBRN event. Training of those who will undertake CBRN field medical care and CBRN first aid must include: ▸knowledge of CBRN agents, their impact on health and the corresponding toxidromes ▸skills to use appropriate equipment ▸use of appropriate means of self-protection ▸an understanding of the additional complexities brought by the need for and interaction of triage, transfer and decontamination. The development of CBRN field medical care and CBRN first aid continues within the ICRC while acknowledging that the opportunities for learning in real situations are extremely limited. Comments from others who work in this domain are welcome.

  7. Impact of the AD 79 explosive eruption on Pompeii, I. Relations amongst the depositional mechanisms of the pyroclastic products, the framework of the buildings and the associated destructive events

    Science.gov (United States)

    Luongo, Giuseppe; Perrotta, Annamaria; Scarpati, Claudio

    2003-08-01

    A quantitative and qualitative evaluation of the damage caused by the products of explosive eruptions to buildings provides an excellent contribution to the understanding of the various eruptive processes during such dramatic events. To this end, the impact of the products of the two main phases (pumice fallout and pyroclastic density currents) of the Vesuvius AD 79 explosive eruption onto the Pompeii buildings has been evaluated. Based on different sources of data, such as photographs and documents referring to the archaeological excavations of Pompeii, the stratigraphy of the pyroclastic deposits, and in situ inspection of the damage suffered by the buildings, the present study has enabled the reconstruction of the events that occurred inside the city when the eruption was in progress. In particular, we present new data related to the C.J. Polibius' house, a large building located inside Pompeii. From a comparison of all of the above data sets, it has been possible to reconstruct, in considerable detail, the stratigraphy of the pyroclastic deposits accumulated in the city, to understand the direction of collapse of the destroyed walls, and to evaluate the stratigraphic level at which the walls collapsed. Finally, the distribution and style of the damage allow us to discuss how the emplacement mechanisms of the pyroclastic currents are influenced by their interaction with the urban centre. All the data suggest that both structure and shape of the town buildings affected the transport and deposition of the erupted products. For instance, sloping roofs 'drained' a huge amount of fall pumice into the 'impluvia' (a rectangular basin in the centre of the hall with the function to collect the rain water coming from a hole in the centre of the roof), thus producing anomalous deposit thicknesses. On the other hand, flat and low-sloping roofs collapsed under the weight of the pyroclastic material produced during the first phase of the eruption (pumice fall). In addition

  8. Studying stellar explosions with Athena

    Science.gov (United States)

    O'Brien, P.; Jonker, P.

    Athena is the second large mission selected in the ESA Cosmic Vision plan. With its large collecting area, high spectral-energy resolution (X-IFU instrument) and impressive grasp (WFI instrument), Athena will truly revolutionise X-ray astronomy. The most prodigious sources of high-energy photons are often transitory in nature. Athena will provide the sensitivity and spectral resolution coupled with rapid response to enable the study of the dynamic sky. Potential sources include: distant Gamma-Ray Bursts to probe the reionisation epoch and find missing baryons in the cosmic web; tidal disruption events to reveal dormant supermassive and intermediate-mass black holes; and supernova explosions to understand progenitors and their environments. We illustrate Athenas capabilities and show how it will be able to constrain the nature of explosive transients including gas metallicity and dynamics.

  9. Explosive Outflows from Forming Massive Stars

    OpenAIRE

    Bally, J.; Ginsburg, A.; Kasliwal, M. M.

    2016-01-01

    AO imaging of the near IR [Fe ii] and H_2 lines and ALMA CO J = 2 − 1 data confirms the explosive nature of the BN/KL outflow in Orion. N-body interactions in compact groups may be responsible for the production of powerful, explosive protostellar outflows and luminous infrared flares. The Orion event may have been triggered by a protostellar merger. First results of a search for Orion-like events in 200 nearby galaxies with the SPitzer InfraRed Intensive Transients Survey (SPIRITS) are brief...

  10. Development in the Detection and Identification of Explosive Residues.

    Science.gov (United States)

    Beveridge, A D

    1992-06-01

    In the past 2 decades, developments in the sensitivity and selectivity of instrument detectors have significantly improved the detection limits for explosives, particularly nitrated organic compounds. Significant improvements have also been made in clean up and recovery procedures for explosive residues. Methods which also have met the criterion of proven effectiveness in identifying explosive components in "real-world" residues from test explosions have been incorporated into systematic analysis protocols for explosive residues. This article first reviews developments in the application of both traditional and novel methods to analysis of unreacted explosives and explosive residues. Compounds used to formulate commercial, military, and "homemade" explosives are then cross-referenced to the analytical methods that have been specifically applied to them, both as pure chemicals and in explosive mixtures. The subsequent focus is on the combinations of methods used to systematically analyze and positively identify residues from improvised explosive devices, from handswabs derived from persons suspected of handling explosives, and from organic gunshot residue. Technology is available to positively identify virtually any unreacted explosive in residue, but no one method can detect all components of all explosives. Investigators and the courts are best served by well-equipped forensic science laboratories staffed with scientists who have gained experience by the successful analysis of post-blast residues from an explosives range and have comprehensive reference collections of physical material, analytical data, and literature. The greatest progress has been made with respect to nitrated organic compounds, but the new generation of commercial explosive slurries and emulsions which are primarily formulated with inorganic salts and non-nitrated organic compounds offer an ongoing challenge. Copyright © 1992 Central Police University.

  11. Explosives tester with heater

    Science.gov (United States)

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

    2010-08-10

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

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

    Science.gov (United States)

    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.

  13. Explosive Technology Group

    Data.gov (United States)

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

  14. Chemical and radiological vulnerability assessment in urban areas

    OpenAIRE

    Stojanović Božidar; Jovašević-Stojanović Milena

    2006-01-01

    Cities and towns are faced with various types of threat from the extraordinary events involving chemical and radiological materials as exemplified by major chemical accidents, radiological incidents, fires, explosions, traffic accidents, terrorist attacks, etc. On the other hand, many sensitive or vulnerable assets exist within cities, such as: settlements, infrastructures, hospitals, schools, churches, businesses, government, and others. Besides emergency planning, the land use planning also...

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

    National Research Council Canada - National Science Library

    J. J. L. du Plessis

    2015-01-01

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

  16. Chemical Reactivity Test (CRT)

    Energy Technology Data Exchange (ETDEWEB)

    Zaka, F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-12-13

    The Chemical Reactivity Test (CRT) is used to determine the thermal stability of High Explosives (HEs) and chemical compatibility between (HEs) and alien materials. The CRT is one of the small-scale safety tests performed on HE at the High Explosives Applications Facility (HEAF).

  17. REHABILITATION OF PATIENTS WITH ENCEPHALOPATHY CAUSED BY ACUTE CHEMICAL AGENTS POISONING. P300 OF AUDITORY EVENT RELATED POTENTIALS AND ELECTROENCEPHALOGRAPHY

    Directory of Open Access Journals (Sweden)

    I. U. Berezina

    2014-01-01

    Full Text Available RELEVANCE. Patients with encephalopathy due to acute chemical agents poisoning have some brain functioning changes and a cognitive impairment during the rehabilitation program. These changes require correction of appropriate diagnostic protocol and treatment.AIM. The aim of this study was to estimate changes of electroencephalography (EEG and the P3 component of the event related potential (P300 ERP that are observed in patients with encephalopathy due to acute chemical agents poisoning during stage of rehabilitation.MATERIAL AND METHODS. The study was included 25 patients (age 37 (32; 51 poisoned different kind of neurotoxic substances (drugs, ethanol and complicated by toxic and hypoxic encephalopathy. They have got the treatment of encephalopathy by mexidol intravenously, mesodiencephalic modulation (MDM and hyperbaric oxygen therapy (HBOT. All patients were recoded EEG (electroencephalograph of “MBN” company, Russia and P300 ERP (“Neuron-Spectrum-5/EP” of “Neurosoft”, Russia according to the international recommendations of clinical neurophysiologists. Neuropsychological testing was used for the assessment of cognitive functions.RESULTS. There were some disturbances in primary electroencephalograms of all subjects. The follow-up EEG recording showed the main group of patients who had got the treatment (mexidol, MDM, HBOT had more often (11 patients the EEG improvements compared to the controls (1 patient. The main group had more rarely the EEG impairments compared to the control group. 6 patients of main group and 3 patients of controls did not have EEG changes during the follow-up EEG recordings. All controls and 17 patients of the main group patients had different cognitive disturbances. After the treatment 15 patients of the main group had improved on neuropsychological tests (MMSE, Munsterberg test, Schulte table, Number Connecting Test. They also had a decrease in the N200, P300 peak latency and an increase in the N200, P300

  18. The Department of Defense Chemical, Biological, Nuclear and High Yield Explosive Response Enterprise: Have We Learned the Lessons to Ensure an Effective Response?

    Science.gov (United States)

    2011-06-10

    storage techniques in Niagara Falls, New York. The Three Mile Island nuclear power plant nearly melted down in 1979. In 1918 , the Spanish Flu pandemic...event of a natural spread of a disease such as avian flu among the human population or a foot and mouth outbreak among the cattle population. Nuclear...Earth, wind, flu , flood, and fire: Early evolution of U.S. nation policy for natural disaster response. Thesis, Command and General Staff College

  19. Explosions and static electricity

    DEFF Research Database (Denmark)

    Jonassen, Niels M

    1995-01-01

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

  20. Cell phone explosion.

    Science.gov (United States)

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

    2016-03-01

    Cell phone explosions and resultant burn injuries are rarely reported in the scientific literature. We report a case of cell phone explosion that occurred when a young male was listening to music while the mobile was plugged in for charging. © The Author(s) 2015.

  1. Steam explosion studies review

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Moon Kyu; Kim, Hee Dong

    1999-03-01

    When a cold liquid is brought into contact with a molten material with a temperature significantly higher than the liquid boiling point, an explosive interaction due to sudden fragmentation of the melt and rapid evaporation of the liquid may take place. This phenomenon is referred to as a steam explosion or vapor explosion. Depending upon the amount of the melt and the liquid involved, the mechanical energy released during a vapor explosion can be large enough to cause serious destruction. In hypothetical severe accidents which involve fuel melt down, subsequent interactions between the molten fuel and coolant may cause steam explosion. This process has been studied by many investigators in an effort to assess the likelihood of containment failure which leads to large scale release of radioactive materials to the environment. In an effort to understand the phenomenology of steam explosion, extensive studies has been performed so far. The report presents both experimental and analytical studies on steam explosion. As for the experimental studies, both small scale tests which involve usually less than 20 g of high temperature melt and medium/large scale tests which more than 1 kg of melt is used are reviewed. For the modelling part of steam explosions, mechanistic modelling as well as thermodynamic modelling is reviewed. (author)

  2. Melt Cast High Explosives

    Directory of Open Access Journals (Sweden)

    Stanisław Cudziło

    2014-12-01

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

  3. Top five industries resulting in injuries from acute chemical incidents—Hazardous Substance Emergency Events Surveillance, nine states, 1999-2008.

    Science.gov (United States)

    Anderson, Ayana R; Wu, Jennifer

    2015-04-10

    Because industries using and/or producing chemicals are located in close proximity to populated areas, U.S. residents are at risk for unintentional chemical exposures. 1999-2008. The Hazardous Substances Emergency Events Surveillance (HSEES) system was operated by the Agency for Toxic Substances and Disease Registry during January 1991-September 2009 to collect data that would enable researchers to describe the public health consequences of chemical releases and to develop activities aimed at reducing the harm from such releases. This report summarizes data for the top five industries resulting in injuries from an acute chemical incident (lasting truck transportation, educational services, chemical manufacturing, utilities, and food manufacturing) accounted for approximately one third of all incidents in which persons were injured as a result of unintentional release of chemicals; the same five industries were responsible for approximately one third of all persons injured as a result of such releases. Acute chemical incidents in these five industries resulted in serious public health implications including the need for evacuations, morbidity, and mortality. PUBLIC HEALTH IMPLICATIONS: Targeting chemical incident prevention and preparedness activities towards these five industries provides an efficient use of resources for reducing chemical exposures. A variety of methods can be used to minimize chemical releases in industries. One example is the Occupational Safety and Health Administration's hierarchy of controls model, which focuses on controlling exposures to occupational hazards. The hierarchy includes elimination, substitution, engineering controls, administrative controls, and use of personal protective equipment.

  4. Hyperspectral requirements for detection of trace explosives agents

    Science.gov (United States)

    Schau, Harvey C.; Jennette, Bryan D.

    2006-05-01

    The ability to remotely detect explosive devices and explosive materials has generated considerable interest over the last several years. The study of remote sensing of explosives date back many decades but recent world events have forced the technology to respond to changing events and bring new technologies to the field in shorter development times than previously thought possible. Several applications have proven both desirable and illusive to date. Most notable is the desire to sense explosives within containers, sealed or otherwise. This requires a sensing device to penetrate the walls of the container, a difficult task when the container is steel or thick cement. Another is the desire to detect explosive vapors which escape from a container into the ambient air. This has been made difficult because explosives are generally formulated to have extremely low vapor pressure. (This has made many gas detection technique not strong candidates for explosive vapor detection due to the low vapor pressure of explosive materials [1].) Because of the many difficulties in a general explosive remote detection, we have attempted to bound the problem into a series of achievable steps with the first step a simple remote detection of TNT-bearing compounds. Prior to discussing our technology, we will first discuss our choice for attacking the problem in this manner.

  5. The November 2009 paroxysmal explosions at Stromboli

    Science.gov (United States)

    Andronico, Daniele; Pistolesi, Marco

    2010-09-01

    Two paroxysmal explosions occurred at Stromboli volcano (Italy) on 8 and 24 November 2009. Analysis of recordings (from video-camera surveillance) indicates that each paroxysm consisted of multiple bursts from different vents. Field surveys, carried out within a few days after the two paroxysmal events, allowed us to gather crucial data on eruptive deposits and document morphological variations occurring at the source vents. Integration of video-analysis and field observations allowed making inferences on the eruptive dynamics of each explosive paroxysm. The 24 November event, in particular, erupted a larger volume and coarser products dispersed further from the summit area, resulting in a more hazardous event compared to the 8 November event that was largely confined to the upper part of the volcano.

  6. Characterization of explosives processing waste decomposition due to composting

    Energy Technology Data Exchange (ETDEWEB)

    Griest, W.H.; Tyndall, R.L.; Stewart, A.J.; Ho, C.H.; Ironside, K.S.; Caton, J.E.; Caldwell, W.M.; Tan, E.

    1991-11-01

    Static pile and mechanically stirred composts generated at the Umatilla Army Depot Activity in a field composting optimization study were chemically and toxicologically characterized to provide data for the evaluation of composting efficiency to decontaminate and detoxify explosives-contaminated soil. Characterization included determination of explosives and 2,4,6,-trinitrotoluene metabolites in composts and their EPA Synthetic Precipitation Leaching Procedure Leachates, leachate toxicity to Ceriodaphnia Dubia and mutagenicity of the leachates and organic solvent extracts of the composts to Ames bacterial strains TA-98 and TA-100. The main conclusion from this study is that composting can effectively reduce the concentrations of explosives and bacterial mutagenicity in explosives -- contaminated soil, and can reduce the aquatic toxicity of leachable compounds. Small levels of explosive and metabolites, bacterial mutagenicity, and leachable aquatic toxicity remain after composting. The ultimate fate of the biotransformed explosives, and the source(s) of residual toxicity and mutagenicity remain unknown.

  7. Grain-scale Dynamics in Explosives

    Energy Technology Data Exchange (ETDEWEB)

    Reaugh, J E

    2002-09-30

    High explosives can have reactions to external stimuli that range from mild pressure bursts to full detonation. The ability to predict these responses is important for understanding the performance as well as the safety and reliability of these important materials. At present, we have only relatively simple phenomenological computational models for the behavior of high explosives under these conditions. These models are limited by the assumption that the explosive can be treated as homogeneous. In reality the explosive is a highly heterogeneous composite of irregular crystallites and plastic binder. The heterogeneous nature of explosives is responsible for many of their unique mechanical and chemical properties. We use computational models to simulate the response of explosives to external mechanical stimuli at the grain-scale level. The ultimate goal of this work is to understand the detailed processes involved with the material response, so that we can develop realistic material models, which can be used in a hydrodynamics/multi-physics code to model real systems. The new material models will provide a more realistic description of the explosive system during the most critical period of ignition and initiation. The focus of this work is to use the results of grain-scale simulations to develop an advanced macroscopic reactive flow model that is consistent with our understanding of the grain-scale details, and that can incorporate such information quantitatively. The objective is to connect changes to observed properties of the explosive (grain size distribution, binder thickness distribution, void shape, size, and separation distribution, binder mechanical properties, etc.) with predictions of the resulting sensitivity and performance.

  8. Diameter effect and detonation front curvature of ideal and non-ideal explosives

    Science.gov (United States)

    Sandstrom, F. W.; Abernathy, R. L.; Leone, M. G.; Banks, M. L.

    2000-04-01

    Diameter effect and detonation front curvature data are presented for several representative ideal and non-ideal explosives, including cast TNT, Tritonal, urea nitrate (UN), ANFO, and two variants of ammonium nitrate (AN)/solid fuel explosives. The ideal vs. non-ideal detonation characteristics of these various explosives are compared and contrasted with respect to particle size and chemical composition.

  9. Venting of gas explosion through relief ducts: interaction between internal and external explosions.

    Science.gov (United States)

    Ferrara, G; Willacy, S K; Phylaktou, H N; Andrews, G E; Di Benedetto, A; Salzano, E; Russo, G

    2008-06-30

    Relief ducts fitted to venting openings is a widespread configuration in the industrial practice. The presence of a duct has been reported to severely increase the violence of the vented explosion posing a problem for the proper design of the venting device. Several studies have reported the leading importance--in the whole complex explosion phenomenology--of a secondary explosion in the duct. Modern approaches in the study of simply vented explosions (without ducts) have focused on the study of the interaction between internal and external explosion as a key issue in the mechanisms of pressure generation. The issue is even more relevant when a duct is fitted to the vent due the confined nature of the external explosion. In this work the interaction between internal and external events is experimentally investigated for gas explosions vented through a relief duct. The work has aimed at studying mechanisms underlying the pressure rise of this venting configuration. The study has put the emphasis on the mutual nature of the interaction. A larger scale than laboratory has been investigated allowing drawing results with a greater degree of generality with respect to data so far presented in literature.

  10. Synthesis of Magnetized Nuclei at Supernova Explosion

    Science.gov (United States)

    Kondratyev, V. N.; Nurtayeva, U. M.; Zhomartova, A. Zh.; Mishenina, T. V.

    Influence of magnetorotational instabilities in astrophysical plasma at supernova explosion on synthesis of chemical elements is investigated. At field strength less than 10 teratesla nuclear magnetic susceptibility exhibits linear regime with enhanced nuclear binding energy for open shell nuclei. Effects of ultra-strong nuclear magnetization are demonstrated to enhance the portion of titanium product. The relation to an excess of titanium isotopes revealed from the Integral mission data and galactic chemical evolution is discussed.

  11. ENVIRONMENTAL TOXICOLOGY OF EXPLOSIVES

    OpenAIRE

    KOYUNCU, Hülya

    2017-01-01

    Explosives are used on a large scale byboth the military and by various civilian industries (e.g. mining, high-energymetalwork, and civil engineering). Explosives utilization contributes to the high environmentalcontamination. TNT(2,4,6-trinitrotoluene), RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) are found mainly in soils and surface waters; there havealso been cases of groundwater contamination. Most explosives are stable du...

  12. CHEMICALS

    CERN Multimedia

    Medical Service

    2002-01-01

    It is reminded that all persons who use chemicals must inform CERN's Chemistry Service (TIS-GS-GC) and the CERN Medical Service (TIS-ME). Information concerning their toxicity or other hazards as well as the necessary individual and collective protection measures will be provided by these two services. Users must be in possession of a material safety data sheet (MSDS) for each chemical used. These can be obtained by one of several means : the manufacturer of the chemical (legally obliged to supply an MSDS for each chemical delivered) ; CERN's Chemistry Service of the General Safety Group of TIS ; for chemicals and gases available in the CERN Stores the MSDS has been made available via EDH either in pdf format or else via a link to the supplier's web site. Training courses in chemical safety are available for registration via HR-TD. CERN Medical Service : TIS-ME :73186 or service.medical@cern.ch Chemistry Service : TIS-GS-GC : 78546

  13. Characterization of rainwater chemical composition after a Southeast Asia haze event: insight of transboundary pollutant transport during the northeast monsoon.

    Science.gov (United States)

    Nadzir, Mohd Shahrul Mohd; Lin, Chin Yik; Khan, Md Firoz; Latif, Mohd Talib; Dominick, Doreena; Hamid, Haris Hafizal Abdul; Mohamad, Noorlin; Maulud, Khairul Nizam Abdul; Wahab, Muhammad Ikram Abdul; Kamaludin, Nurul Farahana; Lazim, Mohamad Azwani Shah Mat

    2017-06-01

    Open biomass burning in Peninsula Malaysia, Sumatra, and parts of the Indochinese region is a major source of transboundary haze pollution in the Southeast Asia. To study the influence of haze on rainwater chemistry, a short-term investigation was carried out during the occurrence of a severe haze episode from March to April 2014. Rainwater samples were collected after a prolonged drought and analyzed for heavy metals and major ion concentrations using inductively coupled plasma mass spectroscopy (ICP-MS) and ion chromatography (IC), respectively. The chemical composition and morphology of the solid particulates suspended in rainwater were examined using a scanning electron microscope coupled with energy-dispersive X-ray spectroscopy (SEM-EDS). The dataset was further interpreted using enrichment factors (EF), statistical analysis, and a back trajectory (BT) model to find the possible sources of the particulates and pollutants. The results show a drop in rainwater pH from near neutral (pH 6.54) to acidic (event in the study area. These findings can be useful in identifying contributions of pollutants from single or multiple sources in rainwater samples during haze episodes.

  14. Laser-Induced Plasma Chemistry of the Explosive RDX with Various Metallic Nanoparticles

    Science.gov (United States)

    2013-04-01

    investigation of shock-produced chemical products in pseudo- aluminized explosive powders explosion,” J. Phys. D 40, 3541–3544 (2007). 6. Y. Song, J.-H. Wu, M...molecular explosives alone. Aluminum powder (typi- cally ∼50 μm average diameter) is frequently added to explosives and propellants to improve their...mixtures is crucial. In a recent study, Song et al. investigated the formation of C and AlO in an aluminized -cyclotrimethylenetrinitra- mine (RDX) shock

  15. Aging of civil explosives (Poster)

    NARCIS (Netherlands)

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

    2014-01-01

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

  16. Shock waves & explosions

    CERN Document Server

    Sachdev, PL

    2004-01-01

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

  17. Intermittent Explosive Disorder

    Science.gov (United States)

    ... Headache Intermittent explosive disorder Symptoms & causes Diagnosis & treatment Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  18. Parametric Explosion Spectral Model

    Energy Technology Data Exchange (ETDEWEB)

    Ford, S R; Walter, W R

    2012-01-19

    Small underground nuclear explosions need to be confidently detected, identified, and characterized in regions of the world where they have never before occurred. We develop a parametric model of the nuclear explosion seismic source spectrum derived from regional phases that is compatible with earthquake-based geometrical spreading and attenuation. Earthquake spectra are fit with a generalized version of the Brune spectrum, which is a three-parameter model that describes the long-period level, corner-frequency, and spectral slope at high-frequencies. Explosion spectra can be fit with similar spectral models whose parameters are then correlated with near-source geology and containment conditions. We observe a correlation of high gas-porosity (low-strength) with increased spectral slope. The relationship between the parametric equations and the geologic and containment conditions will assist in our physical understanding of the nuclear explosion source.

  19. Ammonium nitrate explosion hazards

    Directory of Open Access Journals (Sweden)

    Negovanović Milanka

    2015-01-01

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

  20. Intermittent Explosive Disorder

    Directory of Open Access Journals (Sweden)

    Lut Tamam

    2011-09-01

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

  1. Modeling nuclear explosion

    Science.gov (United States)

    Redd, Jeremy; Panin, Alexander

    2012-10-01

    As a result of the Nuclear Test Ban Treaty, no nuclear explosion tests have been performed by the US since 1992. This appreciably limits valuable experimental data needed for improvement of existing weapons and development of new ones, as well as for use of nuclear devices in non-military applications (such as making underground oil reservoirs or compressed air energy storages). This in turn increases the value of numerical modeling of nuclear explosions and of their effects on the environment. We develop numerical codes simulating fission chain reactions in a supercritical U and Pu core and the dynamics of the subsequent expansion of generated hot plasma in order to better understand the impact of such explosions on their surroundings. The results of our simulations (of both above ground and underground explosions) of various energy yields are presented.

  2. Explosion suppression system

    Science.gov (United States)

    Sapko, Michael J.; Cortese, Robert A.

    1992-01-01

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

  3. Criticality safety in high explosives dissolution

    Energy Technology Data Exchange (ETDEWEB)

    Troyer, S.D.

    1997-06-01

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

  4. [First aid to persons with explosion trauma].

    Science.gov (United States)

    Shapovalov, V M; Samokhvalov, I M

    2012-10-01

    Modern organization providing medical aid to victims of explosion trauma in peace time, the success of which largely depends on the timely and professional interaction among the structures involeved into emergency relief operation is represented in the article. Content and sequence of events providing emergency medical and first medical aid to victims of the explosions, and the appropriateness of allocation affected groups, based on the predicted effectiveness of medical care is analyzed. The algorithm, currently used by ambulance crews, of assistance to victims with explosion and order evacuations is analyzed. The content of therapeutic measures in receipt of the wounded on the steps of skilled and specialized surgical care in accordance with the idea of a separation surgery on three stages (damage control). The content of the main levels of damage control orthopedics is introduced.

  5. Discrimination Analysis of Earthquakes and Man-Made Events Using ARMA Coefficients Determination by Artificial Neural Networks

    Energy Technology Data Exchange (ETDEWEB)

    AllamehZadeh, Mostafa, E-mail: dibaparima@yahoo.com [International Institute of Earthquake Engineering and Seismology (Iran, Islamic Republic of)

    2011-12-15

    A Quadratic Neural Networks (QNNs) model has been developed for identifying seismic source classification problem at regional distances using ARMA coefficients determination by Artificial Neural Networks (ANNs). We have devised a supervised neural system to discriminate between earthquakes and chemical explosions with filter coefficients obtained by windowed P-wave phase spectra (15 s). First, we preprocess the recording's signals to cancel out instrumental and attenuation site effects and obtain a compact representation of seismic records. Second, we use a QNNs system to obtain ARMA coefficients for feature extraction in the discrimination problem. The derived coefficients are then applied to the neural system to train and classification. In this study, we explore the possibility of using single station three-component (3C) covariance matrix traces from a priori-known explosion sites (learning) for automatically recognizing subsequent explosions from the same site. The results have shown that this feature extraction gives the best classifier for seismic signals and performs significantly better than other classification methods. The events have been tested, which include 36 chemical explosions at the Semipalatinsk test site in Kazakhstan and 61 earthquakes (mb = 5.0-6.5) recorded by the Iranian National Seismic Network (INSN). The 100% correct decisions were obtained between site explosions and some of non-site events. The above approach to event discrimination is very flexible as we can combine several 3C stations.

  6. Local Explosion Monitoring using Rg

    Science.gov (United States)

    O'Rourke, C. T.; Baker, G. E.

    2016-12-01

    Rg is the high-frequency fundamental-mode Rayleigh wave, which is only excited by near-surface events. As such, an Rg detection indicates that a seismic source is shallow, generally less than a few km depending on the velocity structure, and so likely man-made. Conversely, the absence of Rg can indicate that the source is deeper and so likely naturally occurring. We have developed a new automated method of detecting Rg arrivals from various explosion sources at local distances, and a process for estimating the likelihood that a source is not shallow when no Rg is detected. Our Rg detection method scans the spectrogram of a seismic signal for a characteristic frequency peak. We test this on the Bighorn Arch Seismic Experiment data, which includes earthquakes, active source explosions in boreholes, and mining explosions recorded on a dense network that spans the Bighorn Mountains and Powder River Basin. The Rg passbands used were 0.4-0.8 Hz for mining blasts and 0.8-1.2 Hz for borehole shots. We successfully detect Rg across the full network for most mining blasts. The lower-yield shots are detectable out to 50 km. We achieve methods that use cross-correlation to detect retrograde motion of the surface waves. Our method shows more complete detection across the network, especially in the Powder River Basin where Rg exhibits prograde motion that does not trigger the existing detector. We also estimate the likelihood that Rg would have been detected from a surface source, based on the measured P amplitude. For example, an event with a large P wave and no detectable Rg would have a high probability of being a deeper event, whereas we cannot confidently determine whether an event with a small P wave and no Rg detection is shallow or not. These results allow us to detect Rg arrivals, which indicate a shallow source, and to use the absence of Rg to estimate the likelihood that a source in a calibrated region is not shallow enough to be man-made.

  7. Caracterização física, química e ecotoxicológica de efluente da indústria de fabricação de explosivos Physical, chemical and ecotoxicological characterization of an effluent from an explosives industry

    Directory of Open Access Journals (Sweden)

    Marcio Barreto-Rodrigues

    2007-01-01

    Full Text Available The production and use of nitroaromatic explosives have resulted in their dissemination into the environment, where their presence in waterways and soil represents an ecological and health hazard. The hazardous characteristics of these compounds need to be carefully studied, so that the impact of their discharge on the environment can be better evaluated. This work presents the characterization of wastewater from Brazilian TNT industry using as analytical techniques mass spectroscopy, chromatography, toxicity assays and other physico-chemical analyses.

  8. Uncertainty in Explosive Yields of Core-Collapse Supernovae

    Science.gov (United States)

    Andrews, Sydney; Fryer, Chris; Even, Wesley P.; Jones, Samuel; Pignatari, Marco; NuGrid Collaboration

    2017-01-01

    The chemical composition of the ejecta from the violent explosions of massive stars has been vital for probing the nature of the explosions and their effect on galactic chemical evolution and universal chemical composition. The sensitivity of numerical explosive nucleosynthetic yields in core-collapse supernovae to several key parameters is examined in one dimension. This uncertainty study is applied to 15, 20, and 25 solar mass stars with different energy prescriptions for shock revival. The effects of the resolution of the temperature and density profiles run through the NuGrid nuclear network are explored, as well as the differences between large and small isotope networks for the initial conditions of the explosion calculations.

  9. Soundless Chemical Demolition Agents

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    The traditional approach to demolishing concrete structures or reducing the size of large rocks or boulders has typically included the use of explosives. The resulting explosions are associated with the obvious risks posed by shock waves and fly rock. Soundless chemical demolition agents (SCDAs) have proven to be viable substitutes for the use of explosives. SCDAs are powdery materials that will expand considerably when mixed with water.

  10. Experimental validation of advanced explosive/metal interactions

    Science.gov (United States)

    Lambert, D. E.

    2005-08-01

    The extremely high power density stored in explosives drives their selection of use in military, mining, demolition, cladding, shock consolidation of powders, shock-induced chemical synthesis and magnetic flux compression processes. The use of distributed initiation locations has emerged as a primary method to customize the detonation front and create desirable output. Explosive/metal systems with multiple, distributed initiation locations create detonation states that do not follow the simple line of sight, or Huygens model and, hence, advanced detonation physics with associated theory are required. The theory of detonation shock dynamics (DSD) is one such description used to provide high fidelity modeling of complex wave structures. A collection of experiments using simultaneous ultra-high speed digital framing and streak film cameras is presented as a means of obtaining spatial and temporal characteristics of complex detonation fronts that validate the DSD descriptions. The method of test, operational conditions and results are given to demonstrate the use of high rate imaging of detonation events and how this validates our understanding of the physics and the capability of advanced detonation wave tracking models.

  11. Thermal Impulse Sensors for use in Explosions

    Science.gov (United States)

    Eilers, Hergen; Gunawidjaja, Ray; Anderson, Benjamin

    2017-06-01

    We have developed temperature and thermal impulse (temperature and duration) sensors for use in explosive fireballs. These sensors are seeded into an explosive fireball and record temperature and duration via morphological phase changes that are optically probed. The thermal impulse sensors include two sensor materials with different phase transition kinetics, and may include a reference material which does not undergo temperature-induced phase changes, and can aid in the optical analysis. Analyzing the sensor materials allows us to determine heating temperature and heating duration of an explosion. The temperature sensors and thermal impulse sensors were recently tested and showed promising results. However, we found that the different components of the thermal impulse sensors tend to get separated during the explosion. We are now evaluating several approaches for redesigning our thermal impulse sensors so that the components remain together during the explosion. These approaches include a core/shell assembly, crosslinking, and co-synthesis. The integrity of the chemically bonded components is evaluated by subjecting the sensors to dispersing forces, while temperature-dependent phase changes of these sensors are assessed by rapid heating using a CO2 laser.

  12. PROLIFERATION AS A KEY EVENT IN DEVELOPMENTAL TOXICITY: "CHEMICAL SCREENING IN HUMAN NEURAL STEM CELLS USING HIGH CONTENT IMAGING

    Science.gov (United States)

    New toxicity testing approaches will rely on in vitro assays to assess chemical effects at the cellular and molecular level. Cell proliferation is imperative to normal development, and chemical disruption of this process can be detrimental to the organism. As part of an effort to...

  13. Seismic Events in Australia and the Aum Shinrikyo

    Science.gov (United States)

    Hennet, C. B.; van der Vink, G. E.; Harvey, D.

    2002-05-01

    On March 20, 1995 the Aum Shinrikyo terrorist group staged a sarin gas attack in the Tokyo Subway system in Japan that killed 12 and injured 5,000 people. Following the subway attack, the U.S. Senate initiated an investigation into the activities of this previously little known yet powerful religious cult. As part of the investigation, the U.S. Senate's Permanent Subcommittee on Investigations requested the IRIS consortium to determine the nature of a seismic event that occurred in 1993 in a remote part of western Australia, where members of the Aum Shinrikyo cult had been trying to mine uranium and had carried out tests with chemical weapons. The time and location of the seismic event coincided with eyewitness accounts of a low flying, bright object and a large explosion. The analysis of seismic data suggests that the magnitude 3.6 event occurred with a force of up to 2,000 tons of high explosive equivalent, but was unlikely to be an explosive detonation. However, the observations and data could be consistent with the impact of an approximately 3 to 4 meter wide iron meteorite, an event that can be expected to occur on land about every 30 years.

  14. Explosion containment device

    Science.gov (United States)

    Benedick, William B.; Daniel, Charles J.

    1977-01-01

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

  15. Surface explosion cavities

    CERN Document Server

    Benusiglio, Adrien; Clanet, Christophe

    2012-01-01

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

  16. The performance of environmental impact assessment in the explosives manufacturing industry in South Africa

    OpenAIRE

    Sandham, Luke Alan; Van der Vyver, Felicity; Retief, Francois Pieter

    2013-01-01

    Explosives manufacture in South Africa is a major component of the chemical and mining industry, and as an important producer of hazardous chemicals it is also a potential contributor to significant environmental impacts. Environmental authorisation of explosives manufacturing activities is based primarily upon the quality of information made available in the Environmental Impact Report (EIR), but the quality of EIR for explosives manufacturing projects has never been investigated. A modified...

  17. Extreme Energy Events Monitoring report

    CERN Document Server

    Baimukhamedova, Nigina

    2015-01-01

    Following paper reflects the progress I made on Summer Student Program within Extreme Energy Events Monitor project I was working on. During 8 week period I managed to build a simple detector system that is capable of triggering events similar to explosions (sudden change in sound levels) and measuring approximate location of the event. Source codes are available upon request and settings described further.

  18. Vapor explosion studies for nuclear and non-nuclear industries

    Energy Technology Data Exchange (ETDEWEB)

    Taleyarkhan, Rusi P. [Arden L. Bement, Jr. Professor Nuclear Engineering, School of Nuclear Engineering, 1290 Nuclear Engineering Building, Room 108C, Purdue University, West Lafayette, IN 47905 (United States)]. E-mail: rusi@purdue.edu

    2005-05-01

    systems during severe accident conditions. Energetics of entrapment boiling induced shocks for explosive and non-explosive conditions were quantified using a modified zero-crossing technique. In honor of Professor R.T. Lahey Jr. the non-dimensional parameter 'L {sub T}' was proposed to delineate the explosion-onset boundary. Experimental evidence suggests that a system with L {sub T} above a threshold value of {approx}65 leads to the growth of perturbations and onset of propagating melt-water explosions. The data appear to offer valuable insights into explosion prevention in nuclear reactors during beyond-design basis accident conditions. An unresolved issue concerns the potential for trigger shocks from chemical ignition reactions between reactive metals in contact with oxide coatings such as rust.

  19. On the spot ethical decision-making in CBRN (chemical, biological, radiological or nuclear event) response: approaches to on the spot ethical decision-making for first responders to large-scale chemical incidents.

    Science.gov (United States)

    Rebera, Andrew P; Rafalowski, Chaim

    2014-09-01

    First responders to chemical, biological, radiological, or nuclear (CBRN) events face decisions having significant human consequences. Some operational decisions are supported by standard operating procedures, yet these may not suffice for ethical decisions. Responders will be forced to weigh their options, factoring-in contextual peculiarities; they will require guidance on how they can approach novel (indeed unique) ethical problems: they need strategies for "on the spot" ethical decision making. The primary aim of this paper is to examine how first responders should approach on the spot ethical decision-making amid the stress and uncertainty of a CBRN event. Drawing on the long-term professional CBRN experience of one of the authors, this paper sets out a series of practical ethical dilemmas potentially arising in the context of a large-scale chemical incident. We propose a broadly consequentialist approach to on the spot ethical decision-making, but one which incorporates ethical values and rights as "side-constraints".

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

    Science.gov (United States)

    2013-10-28

    ... hydrocarbons. Explosive organic nitrate mixtures. Explosive powders. F Flash powder. ] Fulminate of mercury. Fulminate of silver. Fulminating gold. Fulminating mercury. Fulminating platinum. Fulminating silver. G... fulminate. Mercury oxalate. Mercury tartrate. Metriol trinitrate. Minol-2 . MMAN ; methylamine nitrate...

  1. Tools to prevent process safety events at university research facility - chemical risk assessment and experimental set-up risk assessment

    DEFF Research Database (Denmark)

    Jensen, Niels; Jørgensen, Sten Bay

    2014-01-01

    The article discusses the two forms developed to examine the hazards of the chemicals to be used in the experiments in the experimental setup in the Department of Chemical and Biochemical Engineering of the Technical University of Denmark. A system for the safety assessment of new experimental...... setups in university research and teaching laboratories is presented. The significance of the forms for the effort of researchers in improving work with significant hazards is described....

  2. POM Pulses: Characterizing the Physical and Chemical Properties of Particulate Organic Matter (POM) Mobilized by Large Storm Events and its Influence on Receiving Fluvial Systems

    Science.gov (United States)

    Johnson, E. R.; Rowland, R. D.; Protokowicz, J.; Inamdar, S. P.; Kan, J.; Vargas, R.

    2016-12-01

    Extreme storm events have tremendous erosive energy which is capable of mobilizing vast amounts of material from watershed sources into fluvial systems. This complex mixture of sediment and particulate organic matter (POM) is a nutrient source, and has the potential to impact downstream water quality. The impact of POM on receiving aquatic systems can vary not only by the total amount exported but also by the various sources involved and the particle sizes of POM. This study examines the composition of POM in potential sources and within-event POM by: (1) determining the amount and quality of dissolved organic matter (DOM) that can be leached from coarse, medium and fine particle classes; (2) assessing the C and N content and isotopic character of within-event POM; and (3) coupling physical and chemical properties to evaluate storm event POM influence on stream water. Storm event POM samples and source sediments were collected from a forested headwater catchment (second order stream) in the Piedmont region of Maryland. Samples were sieved into three particle classes - coarse (2mm-1mm), medium (1mm-250µm) and fine (organic matter was analyzed. Carbon (C) and Nitrogen (N) amount, C:N ratio, and isotopic analysis of 13C and 15N were performed on solid state event and source material. Future work will include examination of microbial communities associated with POM particle size classes. Physical size class separation of within-event POM exhibited differences in C:N ratios, δ15N composition, and extracted DOM lability. Smaller size classes exhibited lower C:N ratios, more enriched δ15N and more recalcitrant properties in leached DOM. Source material had varying C:N ratios and contributions to leached DOM. These results indicate that both source and size class strongly influence the POM contribution to fluvial systems during large storm events.

  3. The Biggest Explosions in the Universe

    Indian Academy of Sciences (India)

    G am m a ray bursts { w hich are ¯rst detected in energetic gam m a rays and w hich then glow in. X -ray, visible and radio w avelengths { are the result of the biggest explosions in the universe. A stronom ers w onder w hat causes these violent events, and som e of their ideas are discussed in th is article. 1. S eren d ip itou s ...

  4. Concentration-discharge relationships during an extreme event: Contrasting behavior of solutes and changes to chemical quality of dissolved organic material in the Boulder Creek Watershed during the September 2013 flood: SOLUTE FLUX IN A FLOOD EVENT

    Energy Technology Data Exchange (ETDEWEB)

    Rue, Garrett P. [Institute of Arctic and Alpine Research, University of Colorado, Boulder Colorado USA; Rock, Nathan D. [Institute of Arctic and Alpine Research, University of Colorado, Boulder Colorado USA; Gabor, Rachel S. [Institute of Arctic and Alpine Research, University of Colorado, Boulder Colorado USA; Pitlick, John [Department of Geography, University of Colorado, Boulder Colorado USA; Tfaily, Malak [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland Washington USA; McKnight, Diane M. [Institute of Arctic and Alpine Research, University of Colorado, Boulder Colorado USA

    2017-07-01

    During the week of September 10-17, 2013, close to 20 inches of rain fell across Boulder County, Colorado, USA. This rainfall represented a 1000-year event that caused massive hillslope erosion, landslides, and mobilization of sediments. The resultant stream flows corresponded to a 100-year flood. For the Boulder Creek Critical Zone Observatory (BC-CZO), this event provided an opportunity to study the effect of extreme rainfall on solute concentration-discharge relationships and biogeochemical catchment processes. We observed base cation and dissolved organic carbon (DOC) concentrations at two sites on Boulder Creek following the recession of peak flow. We also isolated three distinct fractions of dissolved organic matter (DOM) for chemical characterization. At the upper site, which represented the forested mountain catchment, the concentrations of the base cations Ca, Mg and Na were greatest at the peak flood and decreased only slightly, in contrast with DOC and K concentrations, which decreased substantially. At the lower site within urban corridor, all solutes decreased abruptly after the first week of flow recession, with base cation concentrations stabilizing while DOC and K continued to decrease. Additionally, we found significant spatiotemporal trends in the chemical quality of organic matter exported during the flood recession, as measured by fluorescence, 13C-NMR spectroscopy, and FTICR-MS. Similar to the effect of extreme rainfall events in driving landslides and mobilizing sediments, our findings suggest that such events mobilize solutes by the flushing of the deeper layers of the critical zone, and that this flushing regulates terrestrial-aquatic biogeochemical linkages during the flow recession.

  5. Design optimization of Cassegrain telescope for remote explosive trace detection

    Science.gov (United States)

    Bhavsar, Kaushalkumar; Eseller, K. E.; Prabhu, Radhakrishna

    2017-10-01

    The past three years have seen a global increase in explosive-based terror attacks. The widespread use of improvised explosives and anti-personnel landmines have caused thousands of civilian casualties across the world. Current scenario of globalized civilization threat from terror drives the need to improve the performance and capabilities of standoff explosive trace detection devices to be able to anticipate the threat from a safe distance to prevent explosions and save human lives. In recent years, laser-induced breakdown spectroscopy (LIBS) is an emerging approach for material or elemental investigations. All the principle elements on the surface are detectable in a single measurement using LIBS and hence, a standoff LIBS based method has been used to remotely detect explosive traces from several to tens of metres distance. The most important component of LIBS based standoff explosive trace detection system is the telescope which enables remote identification of chemical constituents of the explosives. However, in a compact LIBS system where Cassegrain telescope serves the purpose of laser beam delivery and light collection, need a design optimization of the telescope system. This paper reports design optimization of a Cassegrain telescope to detect explosives remotely for LIBS system. A design optimization of Schmidt corrector plate was carried out for Nd:YAG laser. Effect of different design parameters was investigated to eliminate spherical aberration in the system. Effect of different laser wavelengths on the Schmidt corrector design was also investigated for the standoff LIBS system.

  6. Spraying explosive formulations. [Quarterly report], July--September 1970

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, G.T.

    1970-12-31

    A composition of 98/2 weight percent PETN/polybutadiene elastomer was formulated, sprayed on bridgewires and electrically initiated, to determine the,feasibility of such deposition of explosives bonded to test surfaces. Test firing resulted in a detonation reaction which could mean that explosive compositions sprayed on test surfaces may be an important tool in testing structural integrity, e.g., as presently in the Vulnerability Testing Program. A semi-automatic apparatus for spraying explosive formulations on chemically etched electric circuits, support membranes and/or test vehicle surfaces has been designed, and improved application processes are being developed.

  7. Fluid Interactions with Explosion-Induced Fractures

    Science.gov (United States)

    Swanson, E.; Sussman, A. J.; Wilson, J.; Broome, S.

    2016-12-01

    Fluids can chemically interact with the fractures they flow through, a process that may affect the movement of fluids in the subsurface. This is a topic of interest to a large variety of research areas, including (but not limited to) production of oil and gas, contaminant tracking, geothermal energy production, CO2 sequestration, and nuclear test monitoring. A study performed as part of the Source Physics Experiment, designed to look at the effects of underground chemical explosions, provides a rare opportunity to compare cores from pre-shot and post-shot rock, from damage created in situ. We present data on the variability of microfracture density with distance from the explosion, as well as the occurrence of fractures that either open or contain clay infill. We find that both open and filled fractures occur more frequently within the post-shot samples (by a factor of up to 4x), with similar spatial distributions. This calls into question the validity of the commonly made assumption that all filled fractures were present prior to the explosive shot, and only open fractures can represent explosion-induced damage. These results suggest that fluid-rock interactions might have a significant influence on the permeabilities that result from explosions, even within a few weeks. Additional data on the mechanical properties of the pre-shot and post-shot core samples show an unexpected pattern during unconfined compressive strength tests: the samples retrieved following 2 successive shots failed at higher stresses than did samples retrieved after 1 shot. We present these results, along with some evidence this behavior may arise from trace differences in water content during testing.

  8. XIT Commercial Explosives Identification Tool

    Science.gov (United States)

    2014-05-01

    Explosives Identification Tool (XIT) was supported by the Canadian Safety and Security Program ( CSSP ) which is led by Defence Research and Development...Explosives Training Unit, and Toronto Police Service, Explosives Disposal Unit. CSSP is a federally-funded program to strengthen Canada’s ability to

  9. Supernova Explosions Stay In Shape

    Science.gov (United States)

    2009-12-01

    remnants. This type of supernova is thought to be caused by a thermonuclear explosion of a white dwarf, and is often used by astronomers as "standard candles" for measuring cosmic distances. On the other hand, the remnants tied to the "core-collapse" supernova explosions were distinctly more asymmetric. This type of supernova occurs when a very massive, young star collapses onto itself and then explodes. "If we can link supernova remnants with the type of explosion", said co-author Enrico Ramirez-Ruiz, also of University of California, Santa Cruz, "then we can use that information in theoretical models to really help us nail down the details of how the supernovas went off." Models of core-collapse supernovas must include a way to reproduce the asymmetries measured in this work and models of Type Ia supernovas must produce the symmetric, circular remnants that have been observed. Out of the 17 supernova remnants sampled, ten were classified as the core-collapse variety, while the remaining seven of them were classified as Type Ia. One of these, a remnant known as SNR 0548-70.4, was a bit of an "oddball". This one was considered a Type Ia based on its chemical abundances, but Lopez finds it has the asymmetry of a core-collapse remnant. "We do have one mysterious object, but we think that is probably a Type Ia with an unusual orientation to our line of sight," said Lopez. "But we'll definitely be looking at that one again." While the supernova remnants in the Lopez sample were taken from the Milky Way and its close neighbor, it is possible this technique could be extended to remnants at even greater distances. For example, large, bright supernova remnants in the galaxy M33 could be included in future studies to determine the types of supernova that generated them. The paper describing these results appeared in the November 20 issue of The Astrophysical Journal Letters. NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA's Science

  10. Insights into a dust event transported through Beijing in spring 2012: Morphology, chemical composition and impact on surface aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Wei [State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871 (China); Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto 862-8502 (Japan); Niu, Hongya [State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871 (China); Key Laboratory of Resource Exploration Research of Hebei Province, Hebei University of Engineering, Handan, Hebei 056038 (China); Zhang, Daizhou [Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto 862-8502 (Japan); Wu, Zhijun [State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871 (China); Chen, Chen [State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871 (China); Beijing Municipal Environmental Monitoring Center, Beijing 100044 (China); Wu, Yusheng; Shang, Dongjie [State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871 (China); Hu, Min, E-mail: minhu@pku.edu.cn [State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871 (China)

    2016-09-15

    Multiple approaches were used to investigate the evolution of surface aerosols in Beijing during the passage of a dust event at high altitude, which was from the Gobi areas of southern Mongolia and covered a wide range of North China. Single particle analysis with electron microscope showed that the majority of coarse particles were mineral ones, and most of them were in the size range of 1–7 μm with a peak of number concentration at about 3.5 μm. Based on elemental composition and morphology, the mineral particles could be classified into several groups, including Si-rich (71%), Ca-rich (15%), Fe-rich (6%), and halite-rich (2%), etc., and they were the main contributors to the aerosol optical depth as the dust occurred. The size distributions of surface aerosols were significantly affected by the dust intrusion. The average number concentration of accumulation mode particles during the event was about 400 cm{sup −3}, which was much lower than that in heavily polluted days (6300 cm{sup −3}). At the stage of floating dust, the number concentration of accumulation mode particles decreased, and coarse particles contributed to total volume concentration of particulate matter as much as 90%. The accumulation mode particles collected in this stage were mostly in the size range of 0.2–0.5 μm, and were rectangular or spherical. They were considered to be particles consisting of ammonium sulfate. New particle formation (NPF) was observed around noon in the three days during the dust event, indicating that the passage of the dust was probably favorable for NPF. - Highlights: • A dust event transported at high altitude through Beijing was investigated. • The dust event caused high variation in surface aerosol number concentrations. • Fine particles in the floating dust period probably consisted of ammonium sulfate. • Passage of the dust induced a favorable condition for new particle formation.

  11. Comparison of results of relative location methods and moment tensor inversion for the nuclear explosions experimented in North Korea

    Science.gov (United States)

    Cho, C.; Shin, J. S.; Kim, G.

    2016-12-01

    The fourth nuclear explosion testing in North Korea was executed in January 6, 2006. This event was located near the previous. The master event method and double difference method(Waldhauser and Ellsworth, 2000) were used to improve the relative location of the events accurately. The master event method with searching for optimal grid was revised. Two results show the very similar locations. First arrival times were picked with cross-correlation method for data of stations surrounding the event location. The distance from the third event to the fourth is about 0.88 km with azimuth 352 356o. Depths from sea level of the events are similar. The fourth location was guessed under the higher elevation of the Mantap mountain. Comparison between cross-correlation of the waveforms of the events show that the value of cross-correlation with the second and the third is higher than that of cross-correlation with the third and the fourth. The results of moment tensor inversion for the events were acquired with the modified TDMT(Minson and Dreger, 2008; Cho, 2015) with frequency band of 0.04 0.08 Hz. The results show the typical characteristics of explosion in T-k plot. The moment magnitude of the second, the third, fourth in the same depth 0.7 km is about 4.4, 4.7, 4.5 respectively. The fourth event has higher amplitude of the vertical component than the others. The third showed the highest amplitude of tangential component among the events. But the real data showed the tangential component. It may be caused by the tectonic stress, topography effect, inhomogeneous structure near source or anomalous chemical effect. The fourth has lower tangential component. This may mean that the depth from the surface was deeper. Moment tensor inversion with 3D viscoelastic FDM was applied with 3D velocity structure derived from Bayesian hierarchical method(Rhie, et al, 2015).

  12. Planar blast scaling with condensed-phase explosives in a shock tube

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Scott L [Los Alamos National Laboratory

    2011-01-25

    Blast waves are strong shock waves that result from large power density deposition into a fluid. The rapid energy release of high-explosive (HE) detonation provides sufficiently high power density for blast wave generation. Often it is desirable to quantify the energy released by such an event and to determine that energy relative to other reference explosives to derive an explosive-equivalence value. In this study, we use condensed-phase explosives to drive a blast wave in a shock tube. The explosive material and quantity were varied to produce blast waves of differing strengths. Pressure transducers at varying lengths measured the post-shock pressure, shock-wave arrival time and sidewall impulse associated with each test. Blast-scaling concepts in a one-dimensional geometry were then used to both determine the energy release associated with each test and to verify the scaling of the shock position versus time, overpressure versus distance, and impulse. Most blast scaling measurements to-date have been performed in a three-dimensional geometry such as a blast arena. Testing in a three-dimensional geometry can be challenging, however, as spherical shock-wave symmetry is required for good measurements. Additionally, the spherical wave strength decays rapidly with distance and it can be necessary to utilize larger (several kg) quantities of explosive to prevent significant decay from occurring before an idealized blast wave has formed. Such a mode of testing can be expensive, require large quantities of explosive, and be limited by both atmospheric conditions (such as rain) and by noise complaints from the population density near the test arena. Testing is possible in more compact geometries, however. Non-planar blast waves can be formed into a quasi-planar shape by confining the shock diffraction with the walls of a shock tube. Regardless of the initial form, the wave shape will begin to approximate a planar front after successive wave reflections from the tube

  13. Construction of hydrogenation stalls for explosions

    Energy Technology Data Exchange (ETDEWEB)

    Raichle, L.

    1943-05-03

    This report contained explanations for different questions that had been asked by the Association of Chemical Manufacturers. The first item discussed was the pressure occurring in hydrogenation stalls in hydrogen explosions. The pressures actually used were much smaller than the maximum design pressure due to burning gases being allowed to escape from the top and front of the stalls since these areas were open and it could not be assumed that the whole stall space was filled with a 32% hydrogen concentration at the beginning of an explosion. The second item discussed was specifications and rules for the building of hydrogenation stalls. These included the calculations for simple wind pressure according to the Building Code with the usual safety factors and the calculations for an inner pressure of 300 kg/m/sup 2/ with the usual safety factors. An explanation of a stall explosion in Poelitz and reinforced stall construction in Poelitz were two other items that were discussed. Appendix I of the report involved maximum pressures and temperature in hydrogen explosions. Diagram I was involved with this. Appendix II discussed the behavior of a hydrogen flame at high emerging velocities and Appendix III discussed stall construction at Poelitz.

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

    Science.gov (United States)

    Hurley, Christoph

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

  15. National Infrastructure Advisory Council: Chemical, Biological, and Radiological Events and the Critical Infrastructure Workforce. Final Report and Recommendations

    Science.gov (United States)

    2008-01-08

    discuss findings and formulate recommendations. SMEs included multiple representatives from DHS, emergency responders, the FBI, the NIH, chemical...World Health Organization (WHO) is available at www.who.int/ csr /disease/influenza/pandemic/en/. • The WHO checklist for pandemic influenza...preparedness planning is available online at: www.who.int/ csr /resources/publications/influenza/FluCheck6web.pdf • To learn more about the WHO’s November

  16. Services Textbook of Explosives

    Science.gov (United States)

    1972-03-01

    and shock effects is obtained by the use of ’primary’ (also known as ’initiatory’) explosives, among the most important of which are mercury fulminate ...Brown had discovered that compressed dry guncotton could be detonated by a mercury fulminate detonator, and a little later they found that compressed wet...of his powder (a mixture of mercury fulminate and potassium chlorate) enclosed in thin copper caps. This idea did not at once meet with the approval

  17. Explosive Welding of Pipes

    Science.gov (United States)

    Drennov, Oleg; Drennov, Andrey; Burtseva, Olga

    2013-06-01

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

  18. Infrasonic and seismic signals from earthquakes and explosions observed with Plostina seismo-acoustic array

    Science.gov (United States)

    Ghica, D.; Ionescu, C.

    2012-04-01

    -wave number analysis). Spectrograms of the recorded infrasonic and seismic data were examined, showing that an earthquake produces acoustic signals with a high energy in the 1 to 5 Hz frequency range, while, for the explosion, this range lays below 0.6 Hz. Using the combined analysis of the seismic and acoustic data, Plostina array can greatly enhance the event detection and localization in the region. The analysis can be, as well, particularly important in identifying sources of industrial explosion, and therefore, in monitoring of the hazard created both by earthquakes and anthropogenic sources of pollution (chemical factories, nuclear and power plants, refineries, mines).

  19. Removal of chemical oxygen demand and dissolved nutrients by a sunken lawn infiltration system during intermittent storm events.

    Science.gov (United States)

    Hou, Lizhu; Yang, Huan; Li, Ming

    2014-01-01

    Urban surface water runoff typically contains high but varying amounts of organic matter and nutrients that require removal before reuse. Infiltration systems such as sunken lawns can improve water quality. However, there is currently insufficient information describing the treatment efficiency of lawn-based infiltration systems. In this study, novel sunken lawn infiltration systems (SLISs) were designed and their pollutant removal effectiveness was assessed. The results revealed that SLISs with Poa pratensis and Lolium perenne effectively removed most chemical oxygen demand (CODCr) and dissolved nutrients. Average CODCr, total nitrogen (TN), ammonium-nitrogen (NH4(+)-N) and total phosphorus (TP) concentrations were reduced by 78.93, 66.64, 71.86 and 75.83%, respectively, and the corresponding effluent concentrations met the standard for urban miscellaneous water consumption in China. The NH4(+)-N in the synthetic runoff was shown to be removed by adsorption during the stormwater dosing and nitrification during subsequent dry days, as well as through uptake by plants. Phosphorus was mainly removed by adsorption and chemical precipitation. The NH4(+)-N and phosphorus Langmuir isotherm model fitted the clay loam soil adsorption process better than the Freundlich model. Overall, these results indicate that an SLIS provides an alternative means of removing runoff pollutants owing to its efficiency, easy operation and maintenance.

  20. Aluminum-Enhanced Underwater Electrical Discharges for Steam Explosion Triggering

    Energy Technology Data Exchange (ETDEWEB)

    HOGELAND, STEVE R.; NELSON, LLOYD S.; ROTH, THOMAS CHRISTOPHER

    1999-07-01

    For a number of years, we have been initiating steam explosions of single drops of molten materials with pressure and flow (bubble growth) transients generated by discharging a capacitor bank through gold bridgewires placed underwater. Recent experimental and theoretical advances in the field of steam explosions, however, have made it important to substantially increase these relatively mild transients in water without using high explosives, if possible. To do this with the same capacitor bank, we have discharged similar energies through tiny strips of aluminum foil submerged in water. By replacing the gold wires with the aluminum strips, we were able to add the energy of the aluminum-water combustion to that normally deposited electrically by the bridgewire explosion in water. The chemical enhancement of the explosive characteristics of the discharges was substantial: when the same electrical energies were discharged through the aluminum strips, peak pressures increased as much as 12-fold and maximum bubble volumes as much as 5-fold above those generated with the gold wires. For given weights of aluminum, the magnitudes of both parameters appeared to exceed those produced by the underwater explosion of equivalent weights of high explosives.

  1. Initiation and Propagation in Primary Explosives

    Science.gov (United States)

    Dickson, P. M.; Field, J. E.

    1993-05-01

    The initiation and propagation of deflagration and detonation in mercury fulminate, lead azide, mercuric-5-nitrotetrazole and silver-5-nitrotetrazole have been studied using various techniques. Streak and framing high-speed photography were used to observe these events directly. The main aim has been to investigate the factors which affect deflagration-to-detonation transition (DDT) and the related phenomenon of dead-pressing, which may be regarded as a failure of the DDT process at high pressed densities. These factors include the variable properties of pressed density, void structure, confinement and charge dimension and geometry, and also fixed properties (for a given explosive) such as shock and thermal sensitivities, heat of explosion and the quantity and state of the reaction products. The nature and strength of the initiating stimulus also have a major effect on the subsequent reaction.

  2. Electronic Nose for Detection of Explosives.

    Science.gov (United States)

    Oakes, Landon; Dobrokhotov, Vladimir

    2010-03-01

    The ability to sense the environment is of critical importance for a broad array of applications ranging from ecosystem health, hazardous materials avoidance/chemical warfare to medical applications. In this research project we use the self-assembled monolayer (SAM)-functionalized nanoparticle-decorated nanosprings as a novel design for sensing vapors associated with explosives. The common requirements for any sensor application are sensitivity, selectivity, refreshability, repeatability, low cost of manufacture, and ease of use. The project goal is to answer these needs through the use of mats of functionalized metal nanoparticle-coated nanosprings as a novel type of low-cost nanomaterials-based gas sensor. The advantage of this approach is that very dilute quantities of airborne explosive products can be accumulated over a few seconds to a few minutes onto our high surface area nanospring electrodes. This will facilitate electronic detection, which in contrast to optical detection methods reduces false positive signals, reduces detector sizes and complexity.

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

    Science.gov (United States)

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

    2017-05-01

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

  4. EXPLOSION AIRBLAST PROGRAM "BLASTO", FOR WEATHER-DEPENDENT PREDICTIONS ON A PERSONAL COMPUTER

    OpenAIRE

    Reed, J.

    1990-01-01

    An airblast prediction program for explosions, called BLASTO has been written for use with IBM-PC (or compatible) computers, to produce overpressure-distance curves for a variety of interactive input conditions. Several common units are allowed for each input, but calculation and output are in SI metric units. Explosion yield (chemical or nuclear) and ambient atmospheric pressure are used to generate a referenced 'Standard' overpressure-distance curve. Explosives may be point charges at any h...

  5. Seismicity and infrasound associated with explosions at Mount St. Helens, 2004-2005: Chapter 6 in A volcano rekindled: the renewed eruption of Mount St. Helens, 2004-2006

    Science.gov (United States)

    Moran, Seth C.; McChesney, Patrick J.; Lockhart, Andrew B.; Sherrod, David R.; Scott, William E.; Stauffer, Peter H.

    2008-01-01

    Six explosions occurred during 2004-5 in association with renewed eruptive activity at Mount St. Helens, Washington. Of four explosions in October 2004, none had precursory seismicity and two had explosion-related seismic tremor that marked the end of the explosion. However, seismicity levels dropped following each of the October explosions, providing the primary instrumental means for explosion detection during the initial vent-clearing phase. In contrast, explosions on January 16 and March 8, 2005, produced noticeable seismicity in the form of explosion-related tremor, infrasonic signals, and, in the case of the March 8 explosion, an increase in event size ~2 hours before the explosion. In both 2005 cases seismic tremor appeared before any infrasonic signals and was best recorded on stations located within the crater. These explosions demonstrated that reliable explosion detection at volcanoes like Mount St. Helens requires seismic stations within 1-2 km of the vent and stations with multiple acoustic sensors.

  6. Reviews of experimental studies on various geometrical contact modes of vapor explosions

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyun-sun; Yamano, Norihiro; Maruyama, Yu; Moriyama, Kiyofumi; Kudo, Tamotsu; Sugimoto, Jun [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-11-01

    The review aims to collect the available experimental information mainly on the stratified and injection modes of vapor explosions and identify areas requiring additional research. A substantial number of works have been performed on the pouring mode of vapor explosions since the pouring mode of vapor explosions is considered to be the most predominant geometric conditions in hypothetical severe accidents in nuclear power plants. However, other types of mode of vapor explosions are relatively less focused. Because of their different sequential progresses and mechanisms of vapor explosions especially at the initial stage of the event, it is essential to identify their mechanisms to make more clear understanding and eventually to provide a methodology for prevention in these types of vapor explosions. It has been recognized that the development of scaling methodologies in the experimental view points to bridge the experiment to prototypic conditions is of great importance under the circumstances of no relevant theoretical models in vapor explosion phenomena. In the sense, it will be useful to perform vapor explosion experiments in an experimental facility which can not only well control the initial and boundary experimental conditions, but also directly measure the energetics of vapor explosions. In particular, it is recommended to study the vapor explosion phenomena in such a facility which has additional capability of providing various contact modes to identify their mechanisms and to scale the energetics of vapor explosions in various contact modes in terms of a precisely measured conversion ratio. (J.P.N.). 51 refs.

  7. Chemical and radiological vulnerability assessment in urban areas

    Directory of Open Access Journals (Sweden)

    Stojanović Božidar

    2006-01-01

    Full Text Available Cities and towns are faced with various types of threat from the extraordinary events involving chemical and radiological materials as exemplified by major chemical accidents, radiological incidents, fires, explosions, traffic accidents, terrorist attacks, etc. On the other hand, many sensitive or vulnerable assets exist within cities, such as: settlements, infrastructures, hospitals, schools, churches, businesses, government, and others. Besides emergency planning, the land use planning also represents an important tool for prevention or reduction of damages on people and other assets due to unwanted events. This paper considers development of method for inclusion vulnerability assessment in land use planning with objective to assess and limit the consequences in cities of likely accidents involving hazardous materials. We made preliminary assessment of criticality and vulnerability of the assets within Belgrade city area in respect to chemical sites and transportation roads that can be exposed to chemical accidents, or terrorist attacks.

  8. Green primary explosives: 5-nitrotetrazolato-N2-ferrate hierarchies.

    Science.gov (United States)

    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.

  9. Action Replay of Powerful Stellar Explosion

    Science.gov (United States)

    2008-03-01

    the new optical study, an estimate of the explosion's energy came from studying an echo of the original light of the explosion. Just as sound bounces off walls of a canyon, so too can light waves create an echo by bouncing off dust clouds in space. The light from these echoes travels a longer path than the light that travels straight toward us, and so can be seen hundreds of years after the supernova itself. First seen by the Cerro-Tololo Inter-American Observatory in Chile, the light echoes were observed in greater detail by Gemini Observatory in Chile. The optical spectra of the light echo were used to confirm that the supernova was a Type Ia and to unambiguously determine the particular class of explosion and therefore its energy. The Chandra data, along with XMM data obtained in 2000, were then independently used to calculate the amount of energy involved in the original explosion, using an analysis of the supernova remnant and state-of-the-art explosion models. Their conclusion confirmed the results from the optical data, namely that the explosion was an especially energetic and bright variety of Type Ia supernova. This agreement provides strong evidence that the detailed explosion models are accurate. "Having these two methods agree lets us breathe a sigh of relief," said Carlos Badenes of Princeton University who led the Chandra and XMM study. "It looks like we're on the right track with trying to understand these big explosions. Their stellar debris really can retain a memory of what created them hundreds of years earlier." Both methods estimated a similar time since the explosion of about 400 years. An extra constraint on the age comes from the lack of recorded historical evidence for a recent supernova in the LMC. Because this star appears in the Southern Hemisphere, it likely would have been seen by navigators who noted similarly bright celestial events if it had occurred less than about 400 years ago. Because Type Ia supernovas have nearly uniform

  10. Primary events in dim light vision: a chemical and spectroscopic approach toward understanding protein/chromophore interactions in rhodopsin.

    Science.gov (United States)

    Fishkin, Nathan; Berova, Nina; Nakanishi, Koji

    2004-01-01

    The visual pigment rhodopsin (bovine) is a 40 kDa protein consisting of 348 amino acids, and is a prototypical member of the subfamily A of G protein-coupled receptors (GPCRs). This remarkably efficient light-activated protein (quantum yield = 0.67) binds the chromophore 11-cis-retinal covalently by attachment to Lys296 through a protonated Schiff base. The 11-cis geometry of the retinylidene chromophore keeps the partially active opsin protein locked in its inactive state (inverse agonist). Several retinal analogs with defined configurations and stereochemistry have been incorporated into the apoprotein to give rhodopsin analogs. These incorporation results along with the spectroscopic properties of the rhodopsin analogs clarify the mode of entry of the chromophore into the apoprotein and the biologically relevant conformation of the chromophore in the rhodopsin binding site. In addition, difference UV, CD, and photoaffinity labeling studies with a 3-diazo-4-oxo analog of 11-cis-retinal have been used to chart the movement of the retinylidene chromophore through the various intermediate stages of visual transduction. Copyright 2004 The Japan Chemical Journal Forum and Wiley Periodicals, Inc.

  11. Photoacoustic Sensing of Explosives

    Science.gov (United States)

    2013-11-01

    weight (6 kg), and its power require- ments (24 W) allow for the high portability of the system. Laser vibrometer measurement, 2 meters from target...2515 P ar tic le v el oc ity (× 1 0 μ m /s ) −1 −2 2 0 1 −1 −2 2 0 1 −1 −2 2 0 1 The laser vibrometer and processing algorithms clearly...technique is depicted for a moving system. Note that the laser vibrometer measures the vibrations caused by the explosive vaporization process. At the same

  12. Laser machining of explosives

    Science.gov (United States)

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

    2000-01-01

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

  13. Femtosecond Studies Of Coulomb Explosion Utilizing Covariance Mapping

    CERN Document Server

    Card, D A

    2000-01-01

    The studies presented herein elucidate details of the Coulomb explosion event initiated through the interaction of molecular clusters with an intense femtosecond laser beam (≥1 PW/cm2). Clusters studied include ammonia, titanium-hydrocarbon, pyridine, and 7-azaindole. Covariance analysis is presented as a general technique to study the dynamical processes in clusters and to discern whether the fragmentation channels are competitive. Positive covariance determinations identify concerted processes such as the concomitant explosion of protonated cluster ions of asymmetrical size. Anti- covariance mapping is exploited to distinguish competitive reaction channels such as the production of highly charged nitrogen atoms formed at the expense of the protonated members of a cluster ion ensemble. This technique is exemplified in each cluster system studied. Kinetic energy analyses, from experiment and simulation, are presented to fully understand the Coulomb explosion event. A cutoff study strongly suggests that...

  14. Robustness Assessment of Building Structures under Explosion

    Directory of Open Access Journals (Sweden)

    Mark Waggoner

    2012-12-01

    Full Text Available Over the past decade, much research has focused on the behaviour of structures following the failure of a key structural component. Particular attention has been given to sudden column loss, though questions remain as to whether this event-independent scenario is relevant to actual extreme events such as explosion. Few studies have been conducted to assess the performance of floor slabs above a failed column, and the computational tools used have not been validated against experimental results. The research program presented in this paper investigates the adequacy of sudden column loss as an idealisation of local damage caused by realistic explosion events, and extends prior work by combining the development of accurate computational models with large-scale testing of a typical floor system in a prototypical steel-framed structure. The floor system consists of corrugated decking topped by a lightly reinforced concrete slab that is connected to the floor beams through shear studs. The design is consistent with typical building practices in the US. The first test has been completed, and subsequent tests are currently being planned. This paper addresses the importance of robustness design for localized damage and includes a detailed description regarding how the research program advances the current state of knowledge for assessing robustness of compositely constructed steel-framed buildings.

  15. SUBJECTIVE ASSESSMENTS OF RADIATION RISK ON THE TERRITORIES ADJACENT TO THE PLACES OF PEACEFUL NUCLEAR EXPLOSIONS

    Directory of Open Access Journals (Sweden)

    G. V. Arkhangelskaya

    2009-01-01

    Full Text Available The article contains results of public opinion assessment of the radiation hazard due to consequences of two accidental peaceful nuclear explosions: Globus-1 in the Ivanovo region and Dnepr-1, Dnepr-2 in the Murmansk region. Results of query poll reveal that population knows about peaceful nuclear explosions that were done many years ago near their settlement. Radiation hazard and territory contamination due to these events is estimated by population as rather high. This public opinion is reflected in the information about consequences of peaceful nuclear explosions presented in the Internet and local printed mass media, especially due to consequences of accidental peaceful nuclear explosion Globus-1.

  16. Explosives detection for aviation security.

    Science.gov (United States)

    Fainberg, A

    1992-03-20

    The threat of terrorism against commercial aviation has received much attention in the past few years. In response, new ways to detect explosives and to combine techniques based on different phenomena into integrated security systems are being developed to improve aviation security. Several leading methods for explosives and weapons detection are presented.

  17. Introduction to High Explosives Science

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-11-17

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

  18. Numerical Model for Hydrovolcanic Explosions.

    Science.gov (United States)

    Mader, Charles; Gittings, Michael

    2007-03-01

    A hydrovolcanic explosion is generated by the interaction of hot magma with ground water. It is called Surtseyan after the 1963 explosive eruption off Iceland. The water flashes to steam and expands explosively. Liquid water becomes water gas at constant volume and generates pressures of about 3GPa. The Krakatoa hydrovolcanic explosion was modeled using the full Navier-Stokes AMR Eulerian compressible hydrodynamic code called SAGE [1] which includes the high pressure physics of explosions. The water in the hydrovolcanic explosion was described as liquid water heated by magma to 1100 K. The high temperature water is treated as an explosive with the hot liquid water going to water gas. The BKW [2] steady state detonation state has a peak pressure of 8.9 GPa, a propagation velocity of 5900 meters/sec and the water is compressed to 1.33 g/cc. [1] Numerical Modeling of Water Waves, Second Edition, Charles L. Mader, CRC Press 2004. [2] Numerical Modeling of Explosions and Propellants, Charles L. Mader, CRC Press 1998.

  19. Explosive microfractures induced by K-metasomatism

    Science.gov (United States)

    Xu, Xing-Wang; Cai, Xin-Ping; Zhang, Bao-Lin; Wang, Jie

    2004-07-01

    Ultra-fine mineral aggregates in K-metasomatic rocks of the Hougou area, northwestern Hebei Province, China contain peculiar and distinct intergranular and intragranular geometries, compositions, and textures. These features indicate solidification of expanded and enclosed relict fluids within tensile microfractures. Two basic morphologic types of textures are present: saw-toothed and wheel-shaped, and several composite patterns also are present, such as X-shaped, grid, and network. The appearance of these features indicate explosion from an instantaneous force. These microscopic explosive microfractures are directly related to the enclosed relict fluids. Theoretical estimates show that volume expansion induced by mineral replacements during K-metasomatism may have caused the K-metasomatic fluids to be confined and strongly compressed in order to build up powerful forces that produced the ultra-fine mineral aggregates and explosive microfractures. The thick-walled texture of K-metasomatic rocks confined fractures that propagated only in the replaced rocks with the lowest strength. Both pumping pressures and the propagation of the K-metasomatism were self-governed and controlled by introduced chemical elements, specially K +.

  20. Microbial bioreporters of trace explosives.

    Science.gov (United States)

    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.

  1. Pyroshock Prediction of Ridge-Cut Explosive Bolts Using Hydrocodes

    Directory of Open Access Journals (Sweden)

    Juho Lee

    2016-01-01

    Full Text Available Pyrotechnic release devices such as explosive bolts are prevalent for many applications due to their merits: high reliability, high power-to-weight ratio, reasonable cost, and more. However, pyroshock generated by an explosive event can cause failures in electric components. Although pyroshock propagations are relatively well understood through many numerical and experimental studies, the prediction of pyroshock generation is still a very difficult problem. This study proposes a numerical method for predicting the pyroshock of a ridge-cut explosive bolt using a commercial hydrocode (ANSYS AUTODYN. A numerical model is established by integrating fluid-structure interaction and complex material models for high explosives and metals, including high explosive detonation, shock wave transmission and propagation, and stress wave propagation. To verify the proposed numerical scheme, pyroshock measurement experiments of the ridge-cut explosive bolts with two types of surrounding structures are performed using laser Doppler vibrometers (LDVs. The numerical analysis results provide accurate prediction in both the time (acceleration and frequency domains (maximax shock response spectra. In maximax shock response spectra, the peaks due to vibration modes of the structures are observed in both the experimental and numerical results. The numerical analysis also helps to identify the pyroshock generation source and the propagation routes.

  2. Effects of Containment on Radionuclide Releases from Underground Nuclear Explosions

    Science.gov (United States)

    Carrigan, C. R.; Sun, Y.

    2016-12-01

    Confirming the occurrence of an underground nuclear explosion can require capturing short-lived noble gas radioisotopes produced by the explosion, sometimes referred to as the "smoking gun" for nuclear explosion detection. It is well known that the radioisotopic distribution resulting from the detonation evolves with time in the explosion cavity. In effect, the explosion cavity or chimney behaves as a chemical reactor. As long as the parent and daughter radionuclides remain in a closed and well-mixed cavity, parameters, such as radioxenon isotopic ratios, can be calculated analytically from a decay-chain network model. When gases from the cavity migrate into the containment regime, consideration of a "leaky reactor" model is more appropriate. We consider several implications of such a leaky reactor model relevant to interpretations of gas samples from the subsurface during an on-site inspection that could potentially be carried out under the Comprehensive Nuclear Test Ban Treaty. Additionally, we have attempted to validate our leaky reactor model against atmospheric observations of radioactive xenon isotopes detected by radionuclide monitoring stations in Japan and Russia following the February 2013 DPRK underground nuclear explosion (Carrigan et al., 2016). While both model uncertainty and observational error are significant, our model of isotopic evolution appears to be in broad agreement with radionuclide observations, and for the first time links atmospheric measurements of radioxenon isotopic ratios to estimates of seismic yield. Carrigan et al., Scientific Reports 6, Article number: 23032 (2016) doi:10.1038/srep23032

  3. Mobility of plume-derived volcanogenic elements in meteoric water at Nyiragongo volcano (Congo) inferred from the chemical composition of single rainfall events

    Science.gov (United States)

    Liotta, Marcello; Shamavu, Patient; Scaglione, Sarah; D'Alessandro, Walter; Bobrowski, Nicole; Bruno Giuffrida, Giovanni; Tedesco, Dario; Calabrese, Sergio

    2017-11-01

    The chemical composition of single rainfall events was investigated at Nyiragongo volcano (Democratic Republic of Congo) with the aim of determining the relative contributions of plume-derived elements. The different locations of the sampling sites allowed both plume-affected samples (hereafter referred to as ;fumigated samples;) and samples representative of the local background to be collected. The chemical composition of the local background reflects the peculiar geographic features of the area, being influenced by biomass burning, geogenic dust, and biological activity. Conversely, fumigated samples contain large amounts of volcanogenic elements that can be clearly distinguished from the local background. These elements are released into the atmosphere from the persistently boiling lava lake of the Nyiragongo crater and from the neonate lava lake of Nyamulagira. These emissions result in a volcanic plume that includes solid particles, acidic droplets, and gaseous species. The chemical signature of the volcanic emissions appears in falling raindrops as they interact with the plume. HCl and HBr readily dissolve in water, and so their ratio in rain samples reflects that of the volcanic plume. The transport of HF is mediated by the large amount of silicate particles generated at the magma-air interface. SO2 is partially converted into SO42- that dissolves in water. The refractory elements dissolved in rain samples derive from the dissolution of silicate particles, and most of them (Al, Mg, Ca, and Sr) are present at exactly the same molar ratios as in the rocks. In contrast, elements such as Na, K, Rb, Cu, and Pb are enriched relative to the whole-rock composition, suggesting that they are volatilized during magma degassing. After correcting for the dissolution of silicate particles, we can define that the volatility of the elements decreases in the following order: Pb ≫ Rb > K > Na. This finding, which is the first for a volcanic plume, is consistent with

  4. Cause and Prevention of Explosions Involving DC Casting of Aluminum Sheet Ingot

    Science.gov (United States)

    Richter, Ray T.; Ekenes, J. Martin

    The casting of aluminum alloy sheet ingot and T-bar presents the potential for some of the most volatile situations that can occur in DC (direct chill) and EMC (Electromagnetic) casting processes. Aluminum Association explosion incident data from over 300 explosions spanning a twenty-year period were reviewed and analyzed looking for common factors and repetitive reasons for explosions. Analysis of explosions occurring during the three stages of sheet ingot casting, `start of cast', `steady state' and `end of cast', were examined and prioritized. Case studies illustrate the need for understanding both technical and non-technical factors contributing to explosions involving molten metal. This paper identifies the major causes of explosions involving DC casting of aluminum alloy sheet ingot and makes recommendations for how to prevent the recurrence of such events and minimize the risk of injury.

  5. Caribbean AIDS explosion examined.

    Science.gov (United States)

    2000-03-13

    Homophobia, sex tourism, infidelity, and poverty are major factors causing a rapid explosion of AIDS and increasingly infecting women in the Caribbean. The region has the second largest incidence of AIDS in the world after Africa. The number of people with the HIV virus is likely greater than 500,000 and could be as high as 700,000, about twice the previously reported figures. Societal norms encourage homosexuals to have heterosexual relationships, and married men to have extramarital affairs, while poverty forces men and women to prostitution, often with tourists. In addition, a survey of 8100 school children in 4 English-speaking Caribbean islands revealed that 42% of the children had experienced sex before the age of 10 years; 62% had experienced it by age 12. This finding may reflect a high rate of child molestation in the region.

  6. Mixing in explosions

    Energy Technology Data Exchange (ETDEWEB)

    Kuhl, A.L.

    1993-12-01

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

  7. An examination of the spatial distribution of the tissue fragments created during a single explosive attack.

    Science.gov (United States)

    DuBois, E; Bowers, K; Rando, C

    2017-10-01

    Throughout the course of a forensic investigation following an explosive attack, the identification and recovery of tissue fragments is of extreme importance. There are few universally accepted methods to achieve this end. This project aims to explore this issue through the examination of the spatial distribution of the tissue fragments resulting from an explosive event. To address this, a two stage pilot study was conducted: first, a series of controlled explosions on porcine carcases was undertaken. Second, the data produced from these explosions were used to chart the spatial distribution of the tissue debris. In the controlled explosions, 3kg military grade explosive was chosen to create the maximum amount of fragmentation; this level of explosive also prevented the complete disappearance of forensic evidence through evaporation. Additionally, the blast created by military grade explosive is highly powerful and would mean that the maximum possible distance was achieved and would therefore allow the recorded distances and pattern spread to be a guideline for forensic recovery of associated with an explosive amount of an unknown size and quality. A total station was employed to record the location of the resulting forensic evidence, with the collected data analysed using R Studio. The observed patterns suggested that the distribution of remains is fairly consistent in trials under similar environmental conditions. This indicates potential for some general guidelines for forensic evidence collection (for example, the distance from the explosion that a search should cover). Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Terror explosive injuries: a comparison of children, adolescents, and adults.

    Science.gov (United States)

    Jaffe, Dena H; Peleg, Kobi

    2010-01-01

    We sought to characterize injuries and outcomes from terror explosions with specific attention to children (0-10 years) and adolescents (11-15 years) compared to adults (16-45 years). Terror explosions target vulnerable populations and result in multidimensional injuries that may vary according to age group. The relative dearth of information regarding terror-related injuries among children inhibits proper preparedness and optimum management during such an event. A retrospective study was performed using data from the national Israel Trauma Registry (October 2000 to December 2005). Included were civilians and nonactive military personnel hospitalized as a result of a terror explosion. During the 5.3-year study period, 49 children (0-10 years), 65 adolescents (11-15 years), and 723 adults (16-45 years) were hospitalized from terror explosions. Children were more likely than adults to sustain severe injuries (27% vs. 12%) and traumatic brain injury (35% vs. 20%) and less likely to sustain injuries to their extremities (35% vs. 57%) or open wounds (39% vs. 59%) (P terror explosions present with different injuries and hospital utilization and outcomes. These results further confirm that preparedness of a pediatric healthcare system is essential for effective management in the event of a future mass casualty incident.

  9. Characterization of explosives processing waste decomposition due to composting. Phase 2, Final report

    Energy Technology Data Exchange (ETDEWEB)

    Griest, W.H.; Tyndall, R.L.; Stewart, A.J.; Ho, C.H.; Ironside, K.S.; Caton, J.E.; Caldwell, W.M.; Tan, E.

    1991-11-01

    Static pile and mechanically stirred composts generated at the Umatilla Army Depot Activity in a field composting optimization study were chemically and toxicologically characterized to provide data for the evaluation of composting efficiency to decontaminate and detoxify explosives-contaminated soil. Characterization included determination of explosives and 2,4,6,-trinitrotoluene metabolites in composts and their EPA Synthetic Precipitation Leaching Procedure Leachates, leachate toxicity to Ceriodaphnia Dubia and mutagenicity of the leachates and organic solvent extracts of the composts to Ames bacterial strains TA-98 and TA-100. The main conclusion from this study is that composting can effectively reduce the concentrations of explosives and bacterial mutagenicity in explosives -- contaminated soil, and can reduce the aquatic toxicity of leachable compounds. Small levels of explosive and metabolites, bacterial mutagenicity, and leachable aquatic toxicity remain after composting. The ultimate fate of the biotransformed explosives, and the source(s) of residual toxicity and mutagenicity remain unknown.

  10. Szilard Prize Lecture: Seismic Monitoring of Nuclear Explosions

    Science.gov (United States)

    Richards, Paul

    2006-04-01

    Seismic monitoring of the more than 2000 nuclear test explosions since 1945 has been vigorously pursued, both to track the weapons development of potential adversaries, and to support initiatives in nuclear arms control, including various test ban treaties. Major funding from the US Department of Defense built up new global seismographic networks and over several decades established practical capability in monitoring nuclear explosions ``teleseismically'' (i.e. from distances more than about 1500 km), for tests that the testing nation did not attempt to conceal. What then is the capability to monitor compliance with, for example, the Comprehensive Nuclear-Test-Ban Treaty (CTBT) of 1996, particularly if evasion scenarios are considered? Note that the CTBT, though not ratified by some countries (including the US), is now being monitored by networks that include seismographic stations at ``regional'' distances (< 1500 km) from candidate explosion locations. Years of R and D have shown that regional signals can be used to monitor down to yields significantly lower than can be detected and identified teleseismically. A US National Academy of Sciences study in 2002 concluded that ``an underground nuclear explosion cannot be confidently hidden if its yield is larger than 1 or 2 kt.'' About 1000 earthquakes and chemical explosions are now detected per day, and documented via seismic data, providing plenty of challenges for nuclear explosion monitoring organizations. Explosion monitoring capability will improve in many parts of the world, due to the growth of networks that monitor even small earthquakes to study seismic hazard. But political problems can impede improved international explosion monitoring, due to national restrictions on data access.

  11. Substorm‐associated explosive magnetic field stretching near the earthward edge of the plasma sheet

    National Research Council Canada - National Science Library

    Kozelova, T. V; Kozelov, B. V

    2013-01-01

    We report a detailed analysis of explosive local magnetic field line stretching just before dipolarization observed by one of Time History of Events and Macroscale Interactions during Substorms (THEMIS...

  12. Discriminating between explosions and earthquakes

    Science.gov (United States)

    Cho, Kwang-Hyun

    2014-12-01

    Earthquake, explosion, and a nuclear test data are compared with forward modeling and band-pass filtered surface wave amplitude data for exploring methodologies to improve earthquake-explosion discrimination. The proposed discrimination method is based on the solutions of a double integral transformation in the wavenumber and frequency domains. Recorded explosion data on June 26, 2001 (39.212°N, 125.383°E) and October 30, 2001 (38.748°N, 125.267°E), a nuclear test on October 9, 2006 (41.275°N, 129.095°E), and two earthquakes on April 14, 2002 (39.207°N, 125.686°E) and June 7, 2002 (38.703°N, 125.638°E), all in North Korea, are used to discriminate between explosions and earthquakes by seismic wave analysis and numerical modeling. The explosion signal is characterized by first P waves with higher energy than that of S waves. Rg waves are clearly dominant at 0.05-0.5 Hz in the explosion data but not in the earthquake data. This feature is attributed to the dominant P waves in the explosion and their coupling with the SH components.

  13. Explosive signatures: Pre & post blast

    Science.gov (United States)

    Bernier, Evan Thomas

    Manuscripts 1 and 2 of this dissertation both involve the pre-blast detection of trace explosive material. The first manuscript explores the analysis of human hair as an indicator of exposure to explosives. Field analysis of hair for trace explosives is quick and non-invasive, and could prove to be a powerful linkage to physical evidence in the form of bulk explosive material. Individuals tested were involved in studies which required handling or close proximity to bulk high explosives such as TNT, PETN, and RDX. The second manuscript reports the results of research in the design and application of canine training aids for non-traditional, peroxide-based explosives. Organic peroxides such as triacetonetriperoxide (TATP) and hexamethylenetriperoxidediamine (HMTD) can be synthesized relatively easily with store-bought ingredients and have become popular improvised explosives with many terrorist groups. Due to the hazards of handling such sensitive compounds, this research established methods for preparing training aids which contained safe quantities of TATP and HMTD for use in imprinting canines with their characteristic odor. Manuscripts 3 and 4 of this dissertation focus on research conducted to characterize pipe bombs during and after an explosion (post-blast). Pipe bombs represent a large percentage of domestic devices encountered by law enforcement. The current project has involved the preparation and controlled explosion of over 90 pipe bombs of different configurations in order to obtain data on fragmentation patterns, fragment velocity, blast overpressure, and fragmentation distance. Physical data recorded from the collected fragments, such as mass, size, and thickness, was correlated with the relative power of the initial device. Manuscript 4 explores the microstructural analysis of select pipe bomb fragments. Shock-loading of the pipe steel led to plastic deformation and work hardening in the steel grain structure as evidenced by optical microscopy and

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

    Science.gov (United States)

    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.

  15. High Frequency Attenuation Modeling and Event Amplitude Estimation in the Southern Nevada Region

    Science.gov (United States)

    Pyle, M. L.; Walter, W. R.; Pasyanos, M.

    2016-12-01

    Measurement of seismic amplitudes plays a critical role in underground explosion monitoring and the discrimination between earthquakes and explosions, which is crucial for global security. In order to improve amplitude estimation at small event-to-station distances, an accurate 2D model of attenuation is important. As part of the Source Physics Experiment (SPE), we develop a detailed attenuation model for the region around southern Nevada and test the model's usefulness in predicting amplitudes of local events. The SPE consists of a series of chemical explosions at the Nevada National Security Site (NNSS) designed to improve our understanding of explosion physics and enable better modeling of explosion sources. A high-resolution attenuation model will aid in the waveform modeling efforts of these experiments, and enable us to take a more detailed look at local event discrimination. To improve our understanding of the propagation of energy from sources in the area to local and regional stations in the western U.S., we invert regional phases to examine the crust and upper mantle attenuation structure of southern Nevada and the surrounding region. We consider observed amplitudes as the frequency-domain product of a source term, a site term, a geometrical spreading term, and an attenuation (Q) term (e.g. Walter and Taylor, 2001). Initially we take a staged approach to first determine the best 1D Q values; next we calculate source terms using the 1D model, and finally we solve for the best 2D Q parameters and site terms considering all frequencies simultaneously. Preliminary results show that our attenuation model correlates quite well with the regional geology, and a small number of comparisons of predicted and observed amplitudes from past SPE shots show reasonable agreement. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  16. Nuclear Explosion Monitoring Research and Engineering Program - Strategic Plan

    Energy Technology Data Exchange (ETDEWEB)

    Casey, Leslie A. [DOE/NNSA

    2004-09-01

    The Department of Energy (DOE)/National Nuclear Security Administration (NNSA) Nuclear Explosion Monitoring Research and Engineering (NEM R&E) Program is dedicated to providing knowledge, technical expertise, and products to US agencies responsible for monitoring nuclear explosions in all environments and is successful in turning scientific breakthroughs into tools for use by operational monitoring agencies. To effectively address the rapidly evolving state of affairs, the NNSA NEM R&E program is structured around three program elements described within this strategic plan: Integration of New Monitoring Assets, Advanced Event Characterization, and Next-Generation Monitoring Systems. How the Program fits into the National effort and historical accomplishments are also addressed.

  17. Hydrogen-poor superluminous stellar explosions.

    Science.gov (United States)

    Quimby, R M; Kulkarni, S R; Kasliwal, M M; Gal-Yam, A; Arcavi, I; Sullivan, M; Nugent, P; Thomas, R; Howell, D A; Nakar, E; Bildsten, L; Theissen, C; Law, N M; Dekany, R; Rahmer, G; Hale, D; Smith, R; Ofek, E O; Zolkower, J; Velur, V; Walters, R; Henning, J; Bui, K; McKenna, D; Poznanski, D; Cenko, S B; Levitan, D

    2011-06-08

    Supernovae are stellar explosions driven by gravitational or thermonuclear energy that is observed as electromagnetic radiation emitted over weeks or more. In all known supernovae, this radiation comes from internal energy deposited in the outflowing ejecta by one or more of the following processes: radioactive decay of freshly synthesized elements (typically (56)Ni), the explosion shock in the envelope of a supergiant star, and interaction between the debris and slowly moving, hydrogen-rich circumstellar material. Here we report observations of a class of luminous supernovae whose properties cannot be explained by any of these processes. The class includes four new supernovae that we have discovered and two previously unexplained events (SN 2005ap and SCP 06F6) that we can now identify as members of the same class. These supernovae are all about ten times brighter than most type Ia supernova, do not show any trace of hydrogen, emit significant ultraviolet flux for extended periods of time and have late-time decay rates that are inconsistent with radioactivity. Our data require that the observed radiation be emitted by hydrogen-free material distributed over a large radius (∼10(15) centimetres) and expanding at high speeds (>10(4) kilometres per second). These long-lived, ultraviolet-luminous events can be observed out to redshifts z > 4.

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

    Science.gov (United States)

    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.

  19. Chemical Sniffing Instrumentation for Security Applications.

    Science.gov (United States)

    Giannoukos, Stamatios; Brkić, Boris; Taylor, Stephen; Marshall, Alan; Verbeck, Guido F

    2016-07-27

    Border control for homeland security faces major challenges worldwide due to chemical threats from national and/or international terrorism as well as organized crime. A wide range of technologies and systems with threat detection and monitoring capabilities has emerged to identify the chemical footprint associated with these illegal activities. This review paper investigates artificial sniffing technologies used as chemical sensors for point-of-use chemical analysis, especially during border security applications. This article presents an overview of (a) the existing available technologies reported in the scientific literature for threat screening, (b) commercially available, portable (hand-held and stand-off) chemical detection systems, and (c) their underlying functional and operational principles. Emphasis is given to technologies that have been developed for in-field security operations, but laboratory developed techniques are also summarized as emerging technologies. The chemical analytes of interest in this review are (a) volatile organic compounds (VOCs) associated with security applications (e.g., illegal, hazardous, and terrorist events), (b) chemical "signatures" associated with human presence, and (c) threat compounds (drugs, explosives, and chemical warfare agents).

  20. Quantification of m(Lg) for Small Explosions

    Science.gov (United States)

    1993-03-12

    associated with the minimum wave velocity (usually the S-wave velocity, but may be the P-wave velocity of a fluid layer) at the current angular...frequency w and let kU be the wavenumber associated with the minimum wave velocity but at the maximum desired fre- quency in the synthetics, wma.. The steps...yield relations for small chemical explosions, in Quantification of mi, for small explosions, Scientific Report No. 1, PL-TR-92-2109, Phillips Lafora

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-04-02

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

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

    Science.gov (United States)

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

    2014-10-01

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

  3. Explosives mimic for testing, training, and monitoring

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. Microglass spheres in ammonium nitrate explosives

    OpenAIRE

    Y. Kazakov; G. Turesheva; Olga Golovchenko; N. Bergeneva; R. Seisembayev

    2010-01-01

    Developed consisting the explosive ammonium nitrate, paraffin and mikrosteklosfer. Due to the input of the explosive paraffin increased water resistance of explosives to 60 minutes. By entering into the explosive mikrosteklosfers been improved caking indices, since steklomikrosfers and paraffin was formed seal between the granules of ammonium nitrate.

  5. Microglass spheres in ammonium nitrate explosives

    Directory of Open Access Journals (Sweden)

    Y. Kazakov

    2010-03-01

    Full Text Available Developed consisting the explosive ammonium nitrate, paraffin and mikrosteklosfer. Due to the input of the explosive paraffin increased water resistance of explosives to 60 minutes. By entering into the explosive mikrosteklosfers been improved caking indices, since steklomikrosfers and paraffin was formed seal between the granules of ammonium nitrate.

  6. Suppression of stratified explosive interactions

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-01-01

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

  7. Explosive Blast Neuropathology and Seizures

    Directory of Open Access Journals (Sweden)

    S. Krisztian eKovacs

    2014-04-01

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

  8. Causes of the Cambrian Explosion

    National Research Council Canada - National Science Library

    M. Paul Smith; David A. T. Harper

    2013-01-01

    .... Recent hypotheses for the Cambrian explosion fall into three main categories: developmental/genetic, ecologic, and abiotic/environmental, with geochemical hypotheses forming an abundant and distinctive subset of the last...

  9. Advances in Raman spectroscopy for explosive identification in aviation security

    Science.gov (United States)

    Santillán, Javier D.; Brown, Christopher D.; Jalenak, Wayne

    2007-04-01

    In the operational airport environment, the rapid identification of potentially hazardous materials such as improvised explosive devices, chemical warfare agents and flammable and explosive liquids is increasingly critical. Peroxide-based explosives pose a particularly insidious threat because they can be made from commonly available and relatively innocuous household chemicals, such as bleach and hydrogen peroxide. Raman spectroscopy has been validated as a valuable tool for rapid identification of chemicals, explosives, and narcotics and their precursors while allowing "line-of-sight" interrogation through bottles or other translucent containers. This enables safe identification of both precursor substances, such as acetone, and end-products, such as TATP, without direct sampling, contamination and exposure by security personnel. To date, Raman systems have been laboratory-based, requiring careful operation and maintenance by technology experts. The capital and ongoing expenses of these systems is also significant. Recent advances in Raman component technologies have dramatically reduced the footprint and cost, while improving the reliability and ease of use of Raman spectroscopy systems. Such technologies are not only bringing the lab to the field, but are also protecting civilians and security personnel in the process.

  10. RELATIONSHIP BETWEEN MEDICINE BALL EXPLOSIVE POWER TESTS, THROWING BALL VELOCITY AND JUMP PERFORMANCE IN TEAM HANDBALL PLAYERS

    Directory of Open Access Journals (Sweden)

    Mourad Fathloun

    2011-04-01

    Full Text Available In this study, the relationships between medicine ball explosive power tests, jump and handball throwing velocity performance in team handball players were investigated. Explosive test was measured by a medicine ball throw. Specific explosive strength was evaluated by making 3 types of overarm throw: standing position, using an adapted chair (without run-up, T w , a 3-step running throw (T 3-Steps and a jump shot (J S . The jump test (SJ, CMJ and FCMJ were determined using the OptoJump. The medicine ball explosive power test was closely related to T 3-Steps . Significant relationships were observed between medicine ball explosive power tests and (J S and (T w . The Medicine ball explosive power test is also positively related to vertical jump ability represented by Squat Jump (SJ and Countermovement Jump (CMJ. The results suggest an association of the medicine ball explosive power tests to performance in throwing events

  11. Furball Explosive Breakout Test

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-08-05

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

  12. Lidar Detection of Explosives Traces

    Directory of Open Access Journals (Sweden)

    Bobrovnikov Sergei M.

    2016-01-01

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

  13. exLOPA for explosion risks assessment.

    Science.gov (United States)

    Markowski, Adam S

    2007-04-11

    The European Union regulations require safety and health protection of workers who are potentially at risk from explosive atmosphere areas. According to the requirements, the operators of installations where potentially explosive atmosphere can occur are obliged to produce an explosion protection document. The key objective of this document is the assessment of explosion risks. This paper is concerned with the so-called explosion layer of protection analysis (exLOPA), which allows for semi-quantitative explosion risk assessment for process plants where explosive atmospheres occur. The exLOPA is based on the original work of CCPS for LOPA but takes into account some typical factors appropriate for explosion, like the probability that an explosive atmosphere will occur, probability that sources of ignition will be present and become effective as well as the probability of failure on demand for appropriate explosion prevention and mitigation means.

  14. Modifications of the chemical structure of phenolics differentially affect physiological activities in pulvinar cells of Mimosa pudica L. I. Multimode effect on early membrane events.

    Science.gov (United States)

    Rocher, Françoise; Dédaldéchamp, Fabienne; Saeedi, Saed; Fleurat-Lessard, Pierrette; Chollet, Jean-Francois; Roblin, Gabriel

    2014-11-01

    A study of the structure-activity relationship carried out on several benzoic acid-related phenolics indicates that this type of compounds hinders the osmocontractile reaction of pulvinar cells in the range of 0-100%. Tentatively, we tried to find a way that could explain this differential action. With this aim, the relationship between the inhibitory effect and important molecular physico-chemical parameters (namely lipophilicity and degree of dissociation) was drawn. In addition, the effect of a variety of these compounds was investigated on their capacity to modify the electrical transmembrane potential and induce modifications in proton fluxes. Finally, using plasma membrane vesicles purified from pulvinar tissues, we examined the effects of some selected compounds on the proton pump activity and catalytic activity of the plasma membrane H(+)-ATPase. Taken together, the results indicate that a modification of the molecular structure of phenolics may induce important variation in the activity of the compound on these early membrane events. Among the tested phenolics, salicylic acid (SA) and acetylsalicylic acid (ASA, aspirin) are of particuler note, as they showed atypical effects on the physiological processes studied. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  15. NQR detection of explosive simulants using RF atomic magnetometers

    Science.gov (United States)

    Monti, Mark C.; Alexson, Dimitri A.; Okamitsu, Jeffrey K.

    2016-05-01

    Nuclear Quadrupole Resonance (NQR) is a highly selective spectroscopic method that can be used to detect and identify a number of chemicals of interest to the defense, national security, and law enforcement community. In the past, there have been several documented attempts to utilize NQR to detect nitrogen bearing explosives using induction sensors to detect the NQR RF signatures. We present here our work on the NQR detection of explosive simulants using optically pumped RF atomic magnetometers. RF atomic magnetometers can provide an order of magnitude (or more) improvement in sensitivity versus induction sensors and can enable mitigation of RF interference, which has classically has been a problem for conventional NQR using induction sensors. We present the theory of operation of optically pumped RF atomic magnetometers along with the result of laboratory work on the detection of explosive simulant material. An outline of ongoing work will also be presented along with a path for a fieldable detection system.

  16. [An investigation to an accident of occupational trichloroethylene explosion].

    Science.gov (United States)

    Yu, L J; Jian, X D; Wang, W J; Wu, Y Z; Wang, K; Jia, J E; Zhang, Z C

    2017-11-20

    Objective: To investigation to an accident of occupational trichloroethylene explosion and analyze the clinical datas. Methods: An investigation was carried out on the explosion of trichloroethylene in a place in shandong province in June 2016, and the clinical data of 4 patients with trichloroethylene poisoning were analyzed. Results: The incident is caused by irregularities in workers, 4 patients were characterized by different levels of the respiratory system, nervous system, liver, and skin lesions. Among them, respiratory system damage was more prominent, mainly manifested as chemical bronchitis and pneumonia, after positive rescue and treatment all recovered and discharged. Conclusions: Trichloroethylene leak can cause severe ex-plosion accidents, can cause workers of the respiratory system, nervous system, liver and skin lesions, mainly glucocorticoids comprehensive therapy has good curative effect.

  17. Sublimation rates of explosive materials : method development and initial results.

    Energy Technology Data Exchange (ETDEWEB)

    Phelan, James M.; Patton, Robert Thomas

    2004-08-01

    Vapor detection of explosives continues to be a technological basis for security applications. This study began experimental work to measure the chemical emanation rates of pure explosive materials as a basis for determining emanation rates of security threats containing explosives. Sublimation rates for TNT were determined with thermo gravimetric analysis using two different techniques. Data were compared with other literature values to provide sublimation rates from 25 to 70 C. The enthalpy of sublimation for the combined data was found to be 115 kJ/mol, which corresponds well with previously reported data from vapor pressure determinations. A simple Gaussian atmospheric dispersion model was used to estimate downrange concentrations based on continuous, steady-state conditions at 20, 45 and 62 C for a nominal exposed block of TNT under low wind conditions. Recommendations are made for extension of the experimental vapor emanation rate determinations and development of turbulent flow computational fluid dynamics based atmospheric dispersion estimates of standoff vapor concentrations.

  18. A Window on Surface Explosions: Tartaric Acid on Cu(110)

    Energy Technology Data Exchange (ETDEWEB)

    Mhatre, B S; Pushkarev, V; Holsclaw, B; Lawton, T J; Sykes, E C. H.; Gellman, A J

    2013-04-18

    Autocatalytic reaction mechanisms are observed in a range of important chemical processes including catalysis, radical-mediated explosions, and biosynthesis. Because of their complexity, the microscopic details of autocatalytic reaction mechanisms have been difficult to study on surfaces and heterogeneous catalysts. Autocatalytic decomposition reactions of S,S- and R,R-tartaric acid (TA) adsorbed on Cu(110) offer molecular-level insight into aspects of these processes, which until now, were largely a matter of speculation. The decomposition of TA/Cu(110) is initiated by a slow, irreversible process that forms vacancies in the adsorbed TA layer, followed by a vacancy-mediated, explosive decomposition process that yields CO{sub 2} and small hydrocarbon products. Initiation of the explosive decomposition of TA/Cu(110) has been studied by measurement of the reaction kinetics, time-resolved low energy electron diffraction (LEED), and time-resolved scanning tunneling microscopy (STM). Initiation results in a decrease in the local coverage of TA and a concomitant increase in the areal vacancy concentration. Observations of explosive TA decomposition on the Cu(651)S surface suggest that initiation does not occur at structural defects in the surface, as has been suggested in the past. Once the vacancy concentration reaches a critical value, the explosive, autocatalytic decomposition step dominates the TA decomposition rate. The onset of the explosive decomposition of TA on Cu(110) is accompanied by the extraction of Cu atoms from the surface to form a (±6,7; {-+}2,1) overlayer that is readily observable using LEED and STM. The explosive decomposition step is second-order in vacancy concentration and accelerates with increasing extent of reaction.

  19. Reducing aluminum dust explosion hazards: case study of dust inerting in an aluminum buffing operation.

    Science.gov (United States)

    Myers, Timothy J

    2008-11-15

    Metal powders or dusts can represent significant dust explosion hazards in industry, due to their relatively low ignition energy and high explosivity. The hazard is well known in industries that produce or use aluminum powders, but is sometimes not recognized by facilities that produce aluminum dust as a byproduct of bulk aluminum processing. As demonstrated by the 2003 dust explosion at aluminum wheel manufacturer Hayes Lemmerz, facilities that process bulk metals are at risk due to dust generated during machining and finishing operations [U.S. Chemical Safety and Hazard Investigation Board, Investigation Report, Aluminum Dust Explosion Hayes Lemmerz International, Inc., Huntington, Indiana, Report No. 2004-01-I-IN, September 2005]. Previous studies have shown that aluminum dust explosions are more difficult to suppress with flame retardants or inerting agents than dust explosions fueled by other materials such as coal [A.G. Dastidar, P.R. Amyotte, J. Going, K. Chatrathi, Flammability limits of dust-minimum inerting concentrations, Proc. Saf. Progr., 18-1 (1999) 56-63]. In this paper, an inerting method is discussed to reduce the dust explosion hazard of residue created in an aluminum buffing operation as the residue is generated. This technique reduces the dust explosion hazard throughout the buffing process and within the dust collector systems making the process inherently safer. Dust explosion testing results are presented for process dusts produced during trials with varying amounts of flame retardant additives.

  20. Craters produced by explosions in a granular medium

    Science.gov (United States)

    Pacheco-Vázquez, F.; Tacumá, A.; Marston, J. O.

    2017-09-01

    We report on an experimental investigation of craters generated by explosions at the surface of a model granular bed. Following the initial blast, a pressure wave propagates through the bed, producing high-speed ejecta of grains and ultimately a crater. We analyzed the crater morphology in the context of large-scale explosions and other cratering processes. The process was analyzed in the context of large-scale explosions, and the crater morphology was compared with those resulting from other cratering processes in the same energy range. From this comparison, we deduce that craters formed through different mechanisms can exhibit fine surface features depending on their origin, at least at the laboratory scale. Moreover, unlike laboratory-scale craters produced by the impact of dense spheres, the diameter and depth do not follow a 1 /4 -power-law scaling with energy, rather the exponent observed herein is approximately 0.30, as has also been found in large-scale events. Regarding the ejecta curtain of grains, its expansion obeys the same time dependence followed by shock waves produced by underground explosions. Finally, from experiments in a two-dimensional system, the early cavity growth is analyzed and compared to a recent study on explosions at the surface of water.

  1. Infrasound signals from the underground nuclear explosions of North Korea

    Science.gov (United States)

    Che, Il-Young; Park, Junghyun; Kim, Inho; Kim, Tae Sung; Lee, Hee-Il

    2014-07-01

    We investigated the infrasound signals from seismic ground motions induced by North Korea's underground nuclear explosions, including the recent third explosion on 2013 February 12. For the third explosion, the epicentral infrasound signals were detected not only by three infrasound network stations (KSGAR, ULDAR and YAGAR) in South Korea but also by two nearby International Monitoring System infrasound stations, IS45 and IS30. The detectability of the signals was limited at stations located on the relatively east side of the epicentre, with large azimuth deviations due to very favourable atmospheric conditions for eastward propagation at stratospheric height in 2013. The stratospheric wind direction was the reverse of that when the second explosion was conducted in 2009 May. The source location of the epicentral infrasound with wave parameters determined at the multiple stations has an offset by about 16.6 km from the reference seismic location. It was possible to determine the infrasonic location with moderate accuracy by the correction of the azimuth deviation due to the eastward winds in the stratosphere. In addition to the epicentral infrasonic signals, diffracted infrasound signals were observed from the second underground nuclear explosion in 2009. The exceptional detectability of the diffracted infrasound was a consequence of the temporal formation of a thin atmospheric inversion layer over the ocean surface when the event occurred.

  2. Molecular Outflows: Explosive versus Protostellar

    Energy Technology Data Exchange (ETDEWEB)

    Zapata, Luis A.; Rodríguez, Luis F.; Palau, Aina; Loinard, Laurent [Instituto de Radioastronomía y Astrofísica, UNAM, Apdo. Postal 3-72 (Xangari), 58089 Morelia, Michoacán, México (Mexico); Schmid-Burgk, Johannes [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121, Bonn (Germany)

    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, but with the full availability of ALMA we expect that more examples will be found in the near future. The main results are the largely different spatial distributions of the explosive flows, consisting of numerous narrow straight filament-like ejections with different orientations and in almost an isotropic configuration, the redshifted with respect to the blueshifted components of the flows (maximally separated in protostellar, largely overlapping in explosive outflows), the very-well-defined Hubble flow-like increase of velocity with distance from the origin in the explosive filaments versus the mostly non-organized CO velocity field in protostellar objects, and huge inequalities in mass, momentum, and energy of the two classes, at least for the case of low-mass flows. Finally, all the molecular filaments in the explosive outflows point back to approximately a central position (i.e., the place where its “exciting source” was located), contrary to the bulk of the molecular material within the protostellar outflows.

  3. Explosion-Earthquake Discrimination at Local Distances

    Science.gov (United States)

    O'Rourke, C. T.; Baker, G. E.; Sheehan, A. F.; Harder, S. H.

    2014-12-01

    Event discrimination research has largely focused on regional distances over the last couple of decades. Most regional discriminants have not been thoroughly tested at local distances, and a recent investigation of P/S ratios from the Source Physics Experiment (SPE) found that they were less effective locally. As discrimination thresholds are reduced, local methods will need to be validated and the physical bases for their performance will need to be understood. We are assessing new and existing methods of source discrimination at 10 to 200 km distance. We use data from a temporary array deployed around the Bighorn Mountains in Wyoming and from nearby US Array stations. Small magnitude local earthquakes, coal mine explosions, and controlled borehole shots were recorded at over 200 broadband and short-period seismometers spaced at 5-35 km intervals across the tectonically complex area. We assess the local discrimination performance of the P/S amplitude ratio, the presence of the fundamental Rayleigh wave Rg, and the signature of scattered Rg in the coda. P/S amplitudes are used because earthquakes typically have higher S-wave energy relative to P than shallow explosions, but the separation of populations is not always effective at local distances. Site effects have a significant impact that may need to be accounted for, along with propagation effects. Specifically, relative P and S site amplifications at basin and mountain stations vary in such a way that they limit separation of the event populations. The Rg phase is only excited by near-surface events, so its presence indicates the likelihood of a man-made source since most earthquakes occur at too great a depth to excite Rg. We implement two methods for detecting Rg: one that uses the cross-correlation of the Hilbert transformed vertical and the radial seismograms, and one that scans a time-frequency representation for the signature of scattered Rg in the coda. These methods are effective in low signal

  4. A mass spectrometer based explosives trace detector

    Science.gov (United States)

    Vilkov, Andrey; Jorabchi, Kaveh; Hanold, Karl; Syage, Jack A.

    2011-05-01

    In this paper we describe the application of mass spectrometry (MS) to the detection of trace explosives. We begin by reviewing the issue of explosives trace detection (ETD) and describe the method of mass spectrometry (MS) as an alternative to existing technologies. Effective security screening devices must be accurate (high detection and low false positive rate), fast and cost effective (upfront and operating costs). Ion mobility spectrometry (IMS) is the most commonly deployed method for ETD devices. Its advantages are compact size and relatively low price. For applications requiring a handheld detector, IMS is an excellent choice. For applications that are more stationary (e.g., checkpoint and alternatives to IMS are available. MS is recognized for its superior performance with regard to sensitivity and specificity, which translate to lower false negative and false positive rates. In almost all applications outside of security where accurate chemical analysis is needed, MS is usually the method of choice and is often referred to as the gold standard for chemical analysis. There are many review articles and proceedings that describe detection technologies for explosives. 1,2,3,4 Here we compare MS and IMS and identify the strengths and weaknesses of each method. - Mass spectrometry (MS): MS offers high levels of sensitivity and specificity compared to other technologies for chemical detection. Its traditional disadvantages have been high cost and complexity. Over the last few years, however, the economics have greatly improved and MS is now capable of routine and automated operation. Here we compare MS and IMS and identify the strengths and weaknesses of each method. - Ion mobility spectrometry (IMS): 5 MS-ETD Screening System IMS is similar in concept to MS except that the ions are dispersed by gas-phase viscosity and not by molecular weight. The main advantage of IMS is that it does not use a vacuum system, which greatly reduces the size, cost, and complexity

  5. TRACER-II: a complete computational model for mixing and propagation of vapor explosions

    Energy Technology Data Exchange (ETDEWEB)

    Bang, K.H. [School of Mechanical Engineering, Korea Maritime Univ., Pusan (Korea, Republic of); Park, I.G.; Park, G.C.

    1998-01-01

    A vapor explosion is a physical process in which very rapid energy transfer occurs between a hot liquid and a volatile, colder liquid when the two liquids come into a sudden contact. For the analyses of potential impacts from such explosive events, a computer program, TRACER-II, has been developed, which contains a complete description of mixing and propagation phases of vapor explosions. The model consists of fuel, fragmented fuel (debris), coolant liquid, and coolant vapor in two-dimensional Eulerian coordinates. The set of governing equations are solved numerically using finite difference method. The results of this numerical simulation of vapor explosions are discussed in comparison with the recent experimental data of FARO and KROTOS tests. When compared to some selected FARO and KROTOS data, the fuel-coolant mixing and explosion propagation behavior agree reasonably with the data, although the results are yet sensitive primarily to the melt breakup and fragmentation modeling. (author)

  6. The Development of Explosive Metalworking in Poland

    Directory of Open Access Journals (Sweden)

    Babul W.

    2014-10-01

    Full Text Available The author coordinated the research in Poland by the collaboration with civil and military scientific and research centres. In result they elaborated detonation process of spraying coats designed and constructed stands equipped with detonative devices, they also elaborated the techniques of basic coating parameter measurement and built devices for commercial and scientific services. In the research the author's achievements within the range of explosive welding have been used. The experience of the scientific teams was very effective. It was observed that many phenomena that take place in the processes of detonative layer coating and explosive welding are the same. In order to obtain a required connection the plastic strain of the connected material surfaces has to be achieved and cumulative flows have to be formed. There are a similar range of the connecting process conditions and the mechanisms of plastic strain. The highest connection strength is obtained when an intermediate zone is formed. The zone has to be composed of the two connected materials. The intermediate layer is formed as a result of mechanical alloying of the materials due to large plastic strain. The plastic strain leads to forming meta-stable phases that have properties of pseudo solid solution, chemical compounds, intermetallic phases and fragmentation corresponding to nanomaterials and amorphous states.

  7. An Analysis of the Initiation Process of Electro-Explosive Devices

    Directory of Open Access Journals (Sweden)

    Paulo Cesar de Carvalho Faria

    2012-03-01

    Full Text Available Electro-explosive devices (an electric resistance encapsulated by a primary explosive fundamentally convert electrical energy into thermal energy, to start off an explosive chemical reaction. Obviously, the activation of those devices shall not happen by accident or, even worse, by intentional exogenous influence. From an ordinary differential equation, which describes the electro-explosive thermal behavior, a remarkable, but certainly not intuitive, dependence of the temperature response on the time constant of the heat transfer process is verified: the temperature profile dramatically changes as the time constant spans a wide range of values, from much lesser than the pulse width to much greater than the pulse period. Based on this dependence, important recommendations, concerning the efficient and safety operation of electro-explosive devices, are proposed.

  8. Nonequilibrium phase coexistence and criticality near the second explosion limit of hydrogen combustion

    Science.gov (United States)

    Newcomb, Lucas B.; Alaghemandi, Mohammad; Green, Jason R.

    2017-07-01

    While hydrogen is a promising source of clean energy, the safety and optimization of hydrogen technologies rely on controlling ignition through explosion limits: pressure-temperature boundaries separating explosive behavior from comparatively slow burning. Here, we show that the emergent nonequilibrium chemistry of combustible mixtures can exhibit the quantitative features of a phase transition. With stochastic simulations of the chemical kinetics for a model mechanism of hydrogen combustion, we show that the boundaries marking explosive domains of kinetic behavior are nonequilibrium critical points. Near the pressure of the second explosion limit, these critical points terminate the transient coexistence of dynamical phases—one that autoignites and another that progresses slowly. Below the critical point temperature, the chemistry of these phases is indistinguishable. In the large system limit, the pseudo-critical temperature converges to the temperature of the second explosion limit derived from mass-action kinetics.

  9. Experiments with vertically and laterally migrating subsurface explosions with applications to the geology of phreatomagmatic and hydrothermal explosion craters and diatremes

    Science.gov (United States)

    Valentine, Greg A.; Graettinger, Alison H.; Macorps, Élodie; Ross, Pierre-Simon; White, James D. L.; Döhring, Erika; Sonder, Ingo

    2015-03-01

    We present results of experiments that use small chemical explosive charges buried in layered aggregates to simulate the effects of subsurface hydrothermal and phreatomagmatic explosions at varying depths and lateral locations, extending earlier experimental results that changed explosion locations only along a vertical axis. The focus is on the resulting crater size and shape and subcrater structures. Final crater shapes tend to be roughly circular if subsurface explosion epicenters occur within each other's footprints (defined as the plan view area of reference crater produced by a single explosion of a given energy, as predicted by an empirical relationship). Craters are elongate if an epicenter lies somewhat beyond the footprint of the previous explosion, such that their footprints overlap, but if epicenters are too far apart, the footprints do not overlap and separate craters result. Explosions beneath crater walls formed by previous blasts tend to produce inclined (laterally directed) ejecta jets, while those beneath crater centers are vertically focused. Lateral shifting of explosion sites results in mixing of subcrater materials by development of multiple subvertical domains of otherwise pure materials, which progressively break down with repeated blasts, and by ejection and fallback of deeper-seated material that had experienced net upward displacement to very shallow levels by previous explosions. A variably developed collar of material that experienced net downward displacement surrounds the subvertical domains. The results demonstrate key processes related to mixing and ejection of materials from different depths during an eruptive episode at a maar-diatreme volcano as well as at other phreatomagmatic and hydrothermal explosion sites.

  10. Thickened aqueous slurry explosive composition

    Energy Technology Data Exchange (ETDEWEB)

    Craig, J.F.M.; Matts, T.C.; Seto, P.F.L.

    1979-01-04

    A thickened slurry explosive composition consists of water, inorganic oxidizing salt, fuel, and thickener wherein the thickener is a mixture of an unmodified guar gum and a hydroxypropyl-modified guar gum. The thickener mixture improves the stability and rheologic properties of the explosive. The preferred thickener mixture contains from 15 to 85% by weight of unmodified guar to 15 to 85% by weight of hydroxypropyl-modified guar and the composition preferably comprises 0.2% to 2.0% by weight of the thickener mixture. The thickener mixture is especially effective in explosive compositions sensitized with gas bubbles or with water-soluble organic nitrate for example, ethylene glycol mononitrate, propylene glycol mononitrate, ethanolamine nitrate, propanolamine nitrate, methylamine nitrate, ethylamine nitrate, ethylenediamine dinitrate, urea nitrate, or aniline nitrate. 14 claims.

  11. Optimal dynamic detection of explosives

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-01-01

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

  12. Seismic Methods of Identifying Explosions and Estimating Their Yield

    Science.gov (United States)

    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. Imaging Detonations of Explosives

    Science.gov (United States)

    2016-04-01

    made using a full-color single-camera pyrometer where wavelength resolution is achieved using the Bayer-type mask covering the sensor chip17 and a...repetition rates up to 10 kHz, were first reported in 1987.44 In 2002, Frost et al., using a combination of high-speed imaging and piezo-resistive gauges...unreferenced). Essentially, 2 light sensors (cameras), each filtered over a narrow wavelength region, observe an event over the same line of sight. The

  14. Hydrothermal processes above the Yellowstone magma chamber: Large hydrothermal systems and large hydrothermal explosions

    Science.gov (United States)

    Morgan, L.A.; Shanks, W.C. Pat; Pierce, K.L.

    2009-01-01

    Hydrothermal explosions are violent and dramatic events resulting in the rapid ejection of boiling water, steam, mud, and rock fragments from source craters that range from a few meters up to more than 2 km in diameter; associated breccia can be emplaced as much as 3 to 4 km from the largest craters. Hydrothermal explosions occur where shallow interconnected reservoirs of steam- and liquid-saturated fluids with temperatures at or near the boiling curve underlie thermal fields. Sudden reduction in confi ning pressure causes fluids to fl ash to steam, resulting in signifi cant expansion, rock fragmentation, and debris ejection. In Yellowstone, hydrothermal explosions are a potentially signifi cant hazard for visitors and facilities and can damage or even destroy thermal features. The breccia deposits and associated craters formed from hydrothermal explosions are mapped as mostly Holocene (the Mary Bay deposit is older) units throughout Yellowstone National Park (YNP) and are spatially related to within the 0.64-Ma Yellowstone caldera and along the active Norris-Mammoth tectonic corridor. In Yellowstone, at least 20 large (>100 m in diameter) hydrothermal explosion craters have been identifi ed; the scale of the individual associated events dwarfs similar features in geothermal areas elsewhere in the world. Large hydrothermal explosions in Yellowstone have occurred over the past 16 ka averaging ??1 every 700 yr; similar events are likely in the future. Our studies of large hydrothermal explosion events indicate: (1) none are directly associated with eruptive volcanic or shallow intrusive events; (2) several historical explosions have been triggered by seismic events; (3) lithic clasts and comingled matrix material that form hydrothermal explosion deposits are extensively altered, indicating that explosions occur in areas subjected to intense hydrothermal processes; (4) many lithic clasts contained in explosion breccia deposits preserve evidence of repeated fracturing

  15. Luck Reveals Stellar Explosion's First Moments

    Science.gov (United States)

    2008-05-01

    Through a stroke of luck, astronomers have witnessed the first violent moments of a stellar explosion known as a supernova. Astronomers have seen thousands of these stellar explosions, but all previous supernovae were discovered days after the event had begun. This is the first time scientists have been able to study a supernova from its very beginning. Seeing one just moments after the event began is a major breakthrough that points the way to unraveling longstanding mysteries about how such explosions really work. Galaxy Before Supernova Explosion NASA's Swift satellite took these images of SN 2007uy in galaxy NGC 2770 before SN 2008D exploded. An X-ray image is on the left; image at right is in visible light. CREDIT: NASA/Swift Science Team/Stefan Immler. Large Image With Labels Large Image Without Labels Galaxy After Supernova Explosion On January 9, 2008, Swift caught a bright X-ray burst from an exploding star. A few days later, SN 2008D appeared in visible light. CREDIT: NASA/Swift Science Team/Stefan Immler. Large Image With Labels Large Image Without Labels "For years, we have dreamed of seeing a star just as it was exploding," said team leader Alicia Soderberg, a Hubble and Carnegie-Princeton Fellow at Princeton University. "This newly-born supernova is going to be the Rosetta Stone of supernova studies for years to come." Theorists had predicted for four decades that a bright burst of X-rays should be produced as the shock wave from a supernova blasts out of the star and through dense material surrounding the star. However, in order to see this burst, scientists faced the nearly-impossible challenge of knowing in advance where to point their telescopes to catch a supernova in the act of exploding. On January 9, luck intervened. Soderberg and her colleagues were making a scheduled observation of the galaxy NGC 2770, 88 million light-years from Earth, using the X-ray telescope on NASA's Swift satellite. During that observation, a bright burst of X

  16. Experiments in gasdynamics of explosions.

    Science.gov (United States)

    Oppenheim, A. K.; Soloukhin, R. I.

    1973-01-01

    Various topics concerning recent accomplishments in experimental studies of gasdynamics of explosions are reviewed. Detonations, shocks, and blast waves form these topics. The most important feature of current studies is the particular attention paid to transient processes and the concomitant progress made in the development of novel experimental means for the study of such processes. The most exciting prospects for the future are associated with possibilities of exploiting knowledge of explosion phenomena for the development of such interesting devices as the gasdynamic laser and the apparatus based on the use of lasers to achieve controlled thermonuclear reaction.

  17. Air Blasts from Cased and Uncased Explosives

    Energy Technology Data Exchange (ETDEWEB)

    Glenn, L. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-04-12

    The problem of a spherical blast in air is solved using the STUN code. For bare charges, the calculations are shown to be in excellent agreement with previous published results. It is demonstrated that, for an unconfined (uncased) chemical explosive, both range and time to effect scale inversely as the cube root of the yield and directly as the cube root of the ambient air density. It is shown that the peak overpressure decays to roughly 1/10 of ambient pressure in a scaled range of roughly 10 m/kg1/3 at sea level. At a height of 30 km, where the ambient density is a factor of 64 less, the range to the same decay increases to 40 m/kg1/3 . As a direct result of the scaling a single calculation suffices for all charge sizes and altitudes. Although the close-in results are sensitive to the nature of the explosive source and the equation of state of the air, this sensitivity is shown to virtually disappear at scaled ranges > 0.5 m/kg1/3 . For cased explosives the case thickness introduces an additional scale factor. Moreover, when the blast wave arrives at the inner case radius the case begins to expand. Fracture occurs when a critical value of the resulting hoop strain is reached, causing the case to shatter into fragments. A model is proposed to describe the size distribution of the fragments and their subsequent motion via drag interaction with the explosion products and ambient air. It is shown that a significant fraction of the charge energy is initially transmitted to the case fragments in the form of kinetic energy; for example, a 1 kg spherical charge with a 5 mm thick steel case has almost 29% of the total charge energy as initial kinetic energy of case fragments. This percentage increases with increasing case thickness and decreases with increasing charge size. The peak overpressure at a given range is 70-85% for cased explosives as compared with uncased and the peak impulse per unit area is 90-95%. The peak overpressure and

  18. Sédimentation détritique continentale synchrone d'un volcanisme explosif dans le Trias terminal à infra-Lias du domaine atlasique (Haute Moulouya, Maroc) (Late Triassic to infra-Liassic continental detrital sedimentation synchronous with an explosive volcanic event in the Atlas area [Hgh Moulouya, Morocco])

    Science.gov (United States)

    Ouarhache, D.; Charriere, A.; Chalot-Prat, F.; El-Wartiti, M.

    2000-11-01

    A volcano-detrital formation (the Tizi-n-Ghachou Formation), essentially composed of reworked basaltic material and volcanic fallout deposits, has been discovered in a southwest-northeast-trending intracontinental decakilometric sedimentary basin. This basin is located on the South Middle Atlas Fault, which separates the Middle Atlas in the northwest from the high Moulouya area to the southeast. The study of the space and the time distribution of these epi- and pyroclastic deposits enables the palæomorphology and the dynamics of this basin to be deciphered. In the subsiding axis of the southern part of the basin, sedimentation was roughly organised in a positive mesosequence with, from bottom to top: coarse conglomerates with basement pebbles corresponding to a piedmont fan; relatively finer fluvial deposits found in conglomeratic channels and drainage deposits from floodplains; clayish siltstones and carbonate sediments (limestones and dolomites) includeing pyroclastic basaltic fragments. This formation was mainly derived from the erosion of Late Triassic tholeiitic continental flood basalts contemporaneous with aerial explosive volcanic events. Erosion, as well as limited distribution of the deposits, suggests regional uplift of the basaltic traps after their emplacement, synchronous with reactivation of magmatic activity on the uplifted margins of the intracontinental basin. Laterally, toward the northwest, an important asymmetry suggests two discrete blocks, whose mobility was controlled by southwest-northeast syn-sedimentary active faults. Lower Liassic carbonate platform deposits overlay these structures. A wide area nalysis of these deposits shows structural trends superimposed on a major crustal suture zone, and suggests a tectono-sedimentary evolution in an uplift-related, extentional, or transtensional, geodynamic setting during the Late Triassic-infra-Liassic period.

  19. Explosive Hydrogen and Helium Burning in Astrophysical Events.

    Science.gov (United States)

    Wallace, Richard Kent

    The nuclear energy generation and nucleosynthesis that occur in hydrogen-rich compositions at temperatures substantially greater than 10('8) K are examined in detail. At these high temperatures, a new kind of nucleosynthetic process (the "rp-process") involving the rapid capture of protons on seed nuclei (or on the products of helium burning in a situation with zero initial metallicity) can lead to the production of heavy elements up to and beyond the iron group with an accompanying energy generation rate greatly modified from that of the (beta)-limited CNO cycle customarily employed in such calculations. New nuclear reaction rates of interest are tabulated, and reaction network calculations are presented to illustrate the application of this process to exploding supermassive stars, accreting neutron stars, novae, and certain chaotic cosmologies. Implications for (gamma)-line astronomy and x-ray burst models are discussed. To further explore the importance of thermonuclear instabilities for accreting neutron stars, the evolution of a 1.41 M(,(CIRCLE)) neutron star accreting both solar and metal-deficient mixtures of hydrogen, helium, and heavy elements at rates ranging from about 10('-11) to 10('-10) M(,(CIRCLE)) per year is examined using a one-dimensional numerical model. The metal deficient compositions may result either from placement of the neutron star in a binary system with a Population II Red Giant or from gravitational settling of heavy ions in the accreted material. For such accretion rates and metallicities, hydrogen burning, mediated by the (beta)-limited CNO cycle, is stable and leads to the accumulation of a thick helium layer with mass 10('23) to 10('25) g and temperature 0.7 (LESSTHEQ) T(,8) (LESSTHEQ) 1.2. Helium ignition occurs under extremely degenerate circumstances and is catastrophically violent. In the lower mass helium shells this runaway is propagated as a convective deflagration; for the thicker layers a detonation front is set up which steepens into a strong relativistic shock wave in the neutron star envelope. In all models greatly super-Eddington luminosities in the outer layers of the neutron star lead to a sustained epoch of radiatively driven mass loss. Observationally, such models may correspond to rapid x-ray transients. The hopeless prospect for constructing a one-dimensional model for (gamma)-ray bursts without magnetic field confinement is reviewed and uncertainties pointed out in the strong screening correction for the helium burning reaction.

  20. Experimental investigation of the effectiveness of the matching of a magnetoplasma compressor with an explosive magnetohydrodynamic generator

    Energy Technology Data Exchange (ETDEWEB)

    Kamrukov, A.S.; Kashnikov, G.N.; Kozlov, N.P.; Kondratenko, M.M.; Lebedev, E.F.; Orlov, V.K.; Ostashev, V.E.; Protasov, Y.S.; Semenov, A.M.

    1984-03-01

    The results of an experimental investigation of the matching of an explosive MHD generator with an actively inductive plasma load--a high-current discharge of an magnetoplasma compressor-are presented. The efficiency of the conversion of the chemical energy of the explosive into the light energy of the discharge was eta/sub rad/approx. = 0.3% and constituted 12--15 J of the radiation energy with 1 g of explosive charge. The possibility of using explosive MHD generators as very efficient (eta/sub rad/> or approx. =1%) sources of electrical power in experiments with high-current radiating discharges is demonstrated.

  1. Test of the stress sensitization model in adolescents following the pipeline explosion.

    Science.gov (United States)

    Shao, Di; Gao, Qing-Ling; Li, Jie; Xue, Jiao-Mei; Guo, Wei; Long, Zhou-Ting; Cao, Feng-Lin

    2015-10-01

    The stress sensitization model states that early traumatic experiences increase vulnerability to the adverse effects of subsequent stressful life events. This study examined the effect of stress sensitization on development of posttraumatic stress disorder (PTSD) symptoms in Chinese adolescents who experienced the pipeline explosion. A total of 670 participants completed self-administered questionnaires on demographic characteristics and degree of explosion exposure, the Childhood Trauma Questionnaire (CTQ), and the Posttraumatic Stress Disorder Checklist-Civilian Version (PCL-C). Associations among the variables were explored using MANOVA, and main effects and interactions were analyzed. Overall MANOVA tests with the PCL-C indicated significant differences for gender (F=6.86, p=.000), emotional abuse (F=6.79, p=.000), and explosion exposure (F=22.40, p=.000). There were significant interactions between emotional abuse and explosion exposure (F=3.98, p=.008) and gender and explosion exposure (F=2.93, p=.033). Being female, childhood emotional abuse, and a high explosion exposure were associated with high PTSD symptom levels. Childhood emotional abuse moderated the effect of explosion exposure on PTSD symptoms. Thus, stress sensitization influenced the development of PTSD symptoms in Chinese adolescents who experienced the pipeline explosion as predicted by the model. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Detecting Weak Explosions at Local Distances by Fusing Multiple Geophysical Phenomenologies

    Energy Technology Data Exchange (ETDEWEB)

    Carmichael, Joshua D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Nemzek, Robert J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Arrowsmith, Stephen J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sentz, Kari [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-23

    Comprehensive explosion monitoring requires the technical capability to identify certain signatures at low signal strengths. For particularly small, evasively conducted explosions, conventional monitoring methods that use single geophysical phenomenologies may produce marginal or absent detections. To address this challenge, we recorded coincident acoustic, seismic and radio-frequency emissions during the above-ground detonation of ~ 2-12 kg solid charges and assessed how waveform data could be fused to increase explosion-screening capability. Our data provided identifiable explosion signatures that we implemented as template-events in multichannel correlation detectors to search for similar, matching waveforms. We thereby observed that these highly sensitive correlation detectors missed explosive events when applied separately to data streams that were heavily contaminated with noise and signal clutter. By then adding the p-values of these statistics through Fisher’s combined probability test, we correctly identified the explosion signals at thresholds consistent with the false alarm rates of the correlation detectors. This resulting Fisher test thereby provided high-probability detections, zero false alarms, and higher theoretical detection capability. We conclude that inclusion of these fusion methods in routine monitoring operations will likely lower both detection thresholds for small explosions, while reducing false attribution rates.

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

    Directory of Open Access Journals (Sweden)

    J. Eiras-Barca

    2018-01-01

    Full Text Available 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.

  4. Pulmonary contusion and hemothorax due to explosion

    National Research Council Canada - National Science Library

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

    2006-01-01

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

  5. Towards the Core-Collapse Supernova Explosion Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Cardall, Christian Y [ORNL; Endeve, Eirik [ORNL; Budiardja, R. D. [University of Tennessee, Knoxville (UTK); Marronetti, Pedro [Florida Atlantic University, Boca Raton; Mezzacappa, Anthony [ORNL

    2012-01-01

    Core-collapse supernovae are amazing displays of astrohysical fireworks - and the optical emission is only a tiny part of the story. These events involve virtually all branches of physics and spawn phenomena observale by every kind of astronomical observation. This richness of theory and observation presents a formidable challenge to their understanding via computer simulations, but we are entering a new era of realism and maturity in modeling the key processes by collapse and explosion.

  6. The Chinese Media Framing of the 2015's Tianjin Explosion

    OpenAIRE

    Yan, Li; Lidong, Lin

    2017-01-01

    This study compares the framing’s patterns of the Chinese traditional media and social media in reporting the incident of Tianjin explosion in 2015. Applying frame-building and framesetting theory, this study explores the interplay between online opinions available on Weibo and the Chinese newspapers in different phases of the crisis event. Moreover, it examines the differences in framing the incident between the state-owned party media and the commercial media. The results reveal that variou...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-08-05

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

  8. In-injection port thermal desorption for explosives trace evidence analysis.

    Science.gov (United States)

    Sigman, M E; Ma, C Y

    1999-10-01

    A gas chromatographic method utilizing thermal desorption of a dry surface wipe for the analysis of explosives trace chemical evidence has been developed and validated using electron capture and negative ion chemical ionization mass spectrometric detection. Thermal desorption was performed within a split/splitless injection port with minimal instrument modification. Surface-abraded Teflon tubing provided the solid support for sample collection and desorption. Performance was characterized by desorption efficiency, reproducibility, linearity of the calibration, and method detection and quantitation limits. Method validation was performed with a series of dinitrotoluenes, trinitrotoluene, two nitroester explosives, and one nitramine explosive. The method was applied to the sampling of a single piece of debris from an explosion containing trinitrotoluene.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-05-09

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-05-31

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

  11. Just-in-time learning is effective in helping first responders manage weapons of mass destruction events.

    Science.gov (United States)

    Motola, Ivette; Burns, William A; Brotons, Angel A; Withum, Kelly F; Rodriguez, Richard D; Hernandez, Salma; Rivera, Hector F; Issenberg, Saul Barry; Schulman, Carl I

    2015-10-01

    Chemical, biologic, radiologic, nuclear, and explosive (CBRNE) incidents require specialized training. The low frequency of these events leads to significant skill decay among first responders. To address skill decay and lack of experience with these high-impact events, educational modules were developed for mobile devices to provide just-in-time training to first responders en route to a CBRNE event. This study assessed the efficacy and usability of the mobile training. Ninety first responders were randomized to a control or an intervention group. All participants completed a pretest to measure knowledge of CBRNE topics. The intervention group then viewed personal protective equipment and weapons of mass destruction field management videos as an overview. Both groups were briefed on a disaster scenario (chemical nerve agent, radiologic, or explosives) requiring them to triage, assess, and manage a patient. Intervention group participants watched a mobile training video corresponding to the scenario. The control group did not receive prescenario video training. Observers rated participant performance in each scenario. After completing the scenarios, all participants answered a cognitive posttest. Those in the intervention group also answered a questionnaire on their impressions of the training. The intervention group outperformed the control group in the explosives and chemical nerve agent scenarios; the differences were statistically significant (explosives, mean of 26.32 for intervention and 22.85 for control, p < 0.01; nerve agent, mean of 23.14 for intervention and 16.61 for control, p < 0.01). There was no statistically significant difference between the groups in the radiologic scenario (mean, 12.7 for intervention and 11.8 for control; p = 0.51). The change in pretest to posttest cognitive scores was significantly higher in the intervention group than in the control group (t = 3.28, p < 0.05). Mobile just-in-time training improved first-responder knowledge

  12. Development of new model for high explosives detonation parameters calculation

    Directory of Open Access Journals (Sweden)

    Jeremić Radun

    2012-01-01

    Full Text Available The simple semi-empirical model for calculation of detonation pressure and velocity for CHNO explosives has been developed, which is based on experimental values of detonation parameters. Model uses Avakyan’s method for determination of detonation products' chemical composition, and is applicable in wide range of densities. Compared with the well-known Kamlet's method and numerical model of detonation based on BKW EOS, the calculated values from proposed model have significantly better accuracy.

  13. Synthesis and characterization of metal carbides nanoparticles produced by electrical explosion of wires.

    Science.gov (United States)

    Ilyin, Alexander P; Nazarenko, Olga B; Tikhonov, Dmitriy V

    2012-10-01

    Tungsten, titanium, tantalum, aluminum carbides nanoparticles were produced by electrical explosion of wires. The explosions were carried out in gaseous mixtures of argon and acetylene at different ratios, argon and propane, and in liquids such as benzene, toluene, decane. The effects of the synthesis conditions on the size and phase composition of metal carbide nanoparticles were investigated. The thermal activity of the prepared powders was studied by the method of differential thermal analysis at the heating in air. Thermodynamic analysis of carbides formation during the process of electrical explosion has been made. The output of the chemical compounds depends on their thermal stability: the more thermally stable they are, the higher their output.

  14. Building national public health capacity for managing chemical events: A case study of the development of health protection services in the United Kingdom

    OpenAIRE

    Palmer, Stephen; Coleman, Gary

    2013-01-01

    The revised International Health Regulations (2005) require that countries develop plans for chemical threats. In 2012, the World Health Assembly reported that most countries had not yet achieved ?adequate capacity'. We review the evolution of chemical hazards services in the United Kingdom, the result of 15 years of grass-roots pressure and an accumulating weight of chemical incidents that eventually convinced the UK Department of Health of the need for a new national public health function,...

  15. Innovative permeable cover system to reduce risks at a chemical munitions burial site

    Energy Technology Data Exchange (ETDEWEB)

    Powels, C.C. [Army Garrison, Aberdeen Proving Ground, MD (United States); Bon, I. [Army Corps. of Engineers, Aberdeen Proving Ground, MD (United States); Okusu, N.M. [ICF Kaiser Engineering, Savannah, GA (United States)

    1997-12-31

    An innovative permeable sand cover with various integrated systems has been designed to contain and treat the Old O-Field chemical munitions landfill at Aberdeen Proving Ground, Maryland. The 18,200 m{sup 2} (4.5 acre) landfill was used from the mid 1930s to the mid 1950s for the disposal of chemical, incendiary, and explosive munitions from domestic and foreign origins, together with contaminated wastes associated with the development and production of chemical warfare agents (CWA). The site is suspected to be contaminated with white phosphorous (WP) (which when dry, spontaneously burns when exposed to air), shock sensitive picric acid fuses and has the potential to contain large quantities of CWA-filled munitions. Historically, one to three explosions or fires occurred per ten-year period at the landfill. Such events have the potential to cause a CWA release to the environment, which could potentially affect densely populated areas. Recovery and decontamination projects conducted at the site in the late 1940s and early 1950s used large amounts of decontamination chemicals (containing solvents) and fuels which further contaminated the area. The groundwater downgradient of the landfill is contaminated with volatile organic compounds, metals, explosives and CWA degradation compounds and is currently being contained by a groundwater extraction and treatment system. This report describes a remedial action program for the site.

  16. Experimental Investigations of Multiphase Explosions

    Science.gov (United States)

    Carney, Joel R.; Lightstone, James M.; McGrath, Thomas P.

    2009-12-01

    The addition of solid fuel particles to explosive formulations generally reduces the detonation velocity, but can enhance the blast performance if prompt combustion of the particles occurs in the detonation products and surrounding air early enough to support the shock. The degree to which fuel particles burn heavily depends on their dispersal throughout the explosion field and access to oxidizers. To distinguish the factors affecting the dispersal of fuel particles from those controlling their combustion, we began by analyzing the dispersal of equivalent mock inert particles. Solid glass spheres embedded in detonating small explosive charges were tracked using high-speed digital shadowgraphy. Two different particle sizes, 3 and 30 μm, and different mass fractions in the explosive compositions were considered. Shadowgraphs and pressure measurements were compared to the predictions of a newly developed multiphase numerical model. Reactive aluminum particles in the range of 1 to 120 μm in diameter were also analyzed. During the first 50 μs of the expansion, the general trend for both reactive and inert particles is for the smaller particles to expand near or beyond the leading shock wave to a greater extent than the larger particles. Expansion beyond the initial shock from the detonation is presumed to occur when particles agglomerate. The results are consistent with the predictions of the numerical models, highlighting the role of simple factors such as particle size and density in the early time expansion and mixing of fuels for enhanced blast applications.

  17. Explosive micro-bubble actuator

    NARCIS (Netherlands)

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

    2007-01-01

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

  18. Risperidone and Explosive Aggressive Autism.

    Science.gov (United States)

    Horrigan, Joseph P.; Barnhill, L. Jarrett

    1997-01-01

    In this study, 11 males with autism and mental retardation were administered risperidone. Substantial clinical improvement was noted almost immediately; patients with aggression, self-injury, explosivity, and poor sleep hygiene were most improved. The modal dose for optimal response was 0.5 mg bid. Weight gain was a significant side effect.…

  19. Lead-free primary explosives

    Science.gov (United States)

    Huynh, My Hang V.

    2010-06-22

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

  20. The Core-Collapse Supernova Explosion Mechanism

    Science.gov (United States)

    Müller, Bernhard

    2017-11-01

    The explosion mechanism of core-collapse supernovae is a long-standing problem in stellar astrophysics. We briefly outline the main contenders for a solution and review recent efforts to model core-collapse supernova explosions by means of multi-dimensional simulations. Focusing on the neutrino-driven mechanism, we summarize currents efforts to predict supernova explosion and remnant properties.

  1. 30 CFR 7.100 - Explosion tests.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Explosion tests. 7.100 Section 7.100 Mineral... Underground Coal Mines Where Permissible Electric Equipment is Required § 7.100 Explosion tests. (a) Test... agree. (ii) Remove all parts that do not contribute to the operation or ensure the explosion-proof...

  2. Successful treatment of a severely injured victim from 8.12 Tianjin Port Explosion, China.

    Science.gov (United States)

    Zhang, Wen-Xu; Gao, Sheng-Ting; Zhang, Xiao-Ning; Zhen, Wei-Feng; Zhu, Yu; Wang, Na; Shi, Zhen-Hua; Guo, Ying; Ding, Dong-Rui; Meng, Xiang-Zhong

    2015-01-01

    A male patient, 55 years old, was found from a container yard 65 h later following a chemical warehouse explosion in Tianjin, China on August 12, 2015. He was about 50 m away from the explosion center. He was subjected to compound multiple trauma, multi-viscera function damage, multiple fractures, hemothorax, traumatic wet lung, respiratory failure I, hypovolemic shock and impaired liver and kidney functions. After a series of successful treatments, he was rescued and recovered well.

  3. Explosion Power and Pressure Desensitization Resisting Property of Emulsion Explosives Sensitized by MgH2

    Science.gov (United States)

    Cheng, Yangfan; Ma, Honghao; Liu, Rong; Shen, Zhaowu

    2014-07-01

    Due to low detonation power and pressure desensitization problems that traditional emulsion explosives encounter in utilization, a hydrogen-based emulsion explosives was devised. This type of emulsion explosives is sensitized by hydrogen-containing material MgH2, and MgH2 plays a double role as a sensitizer and an energetic material in emulsion explosives. Underwater explosion experiments and shock wave desensitization experiments show that an MgH2 emulsion explosives has excellent detonation characteristics and is resistant to pressure desensitization. The pressure desensitization-resistant mechanism of MgH2 emulsion explosives was investigated using scanning electron microscopy.

  4. Numerical Simulation and Experimental Study on Formation of High Concentration of H2 Generated by Gas Explosion

    Directory of Open Access Journals (Sweden)

    Lei Baiwei

    2016-10-01

    Full Text Available In coal mine fire rescues, if the abnormal increase of gas concentration occurs, it is the primary thing to analyze the reasons and identify sources of the abnormal forming, which is also the basis of judge the combustion state of fire area and formulate proper fire reliefs. Nowadays, related researches have recognized the methane explosion as the source of high concentration of H2 formation, but there are few studies about the conditions and reaction mechanism of gas explosion generating high concentration of H2.Therefore, this paper uses the chemical kinetic calculation software, ChemKin, and the 20L spherical explosion experimental device to simulate the generating process and formation conditions of H2 in gas explosion. The experimental results show that: the decomposition of water vapor is the main base element reaction (R84 which leads to the generation of H2.The free radical H is the key factor to influence the formation of H2 generated from gas explosion. With the gradual increase of gas explosion concentration, the explosive reaction becomes more incomplete, and then the generating quantity of H2 increases gradually. Experimental results of 20L spherical explosion are consistent with the change trend about simulation results, which verifies the accuracy of simulation analysis. The results of explosion experiments show that when gas concentration is higher than 9%, the incomplete reaction of methane explosion increases which leads to the gradual increase of H2 formation.

  5. Chemical equilibrium modeling of detonation

    Energy Technology Data Exchange (ETDEWEB)

    Fried, Laurence E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bastea, Sorin [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2010-05-19

    Energetic materials are unique for having a strong exothermic reactivity, which has made them desirable for both military and commercial applications. Energetic materials are commonly divided into high explosives, propellants, and pyrotechnics. We will focus on high explosive (HE) materials here, although there is a great deal of commonality between the classes of energetic materials. Furthermore the history of HE materials is long, their condensed-phase chemical properties are poorly understood.

  6. Florida county health department, environmental health 2006 survey: do rural counties know "what to do' in a chemical or all-hazards event?

    Science.gov (United States)

    Becker, Alan; Suther, Sandra; Dutton, Matthew; Kearney, Gregory D; Xu, Xiaohui

    2015-01-01

    The objective of the study described here was to determine basic plans and collaboration with first responder stakeholders and to identify perceived roles and responsibilities in preparing for and responding to a chemical disaster. A survey was developed and provided to environmental health personnel at county health departments (CHDs) in Florida. Most of the counties had good collaborative relationships with first responder stakeholders. A little more than half of the respondents had access to a resource manual with contact information and had developed and maintained a chemical plan. Rural counties were less likely to know "what to do" or their responsibility in a chemical disaster; however, both rural and nonrural counties were equally likely not to have a written plan. Public health agencies at the local CHD must be the communicators of public health messages in coordination with the incident commander and the state communications office in a chemical disaster, so it is important to strengthen collaboration and cooperation with chemical response stakeholders.

  7. An Improved Shock Model for Bare and Covered Explosives

    Science.gov (United States)

    Scholtes, Gert; Bouma, Richard

    2017-06-01

    TNO developed a toolbox to estimate the probability of a violent event on a ship or other platform, when the munition bunker is hit by e.g. a bullet or fragment from a missile attack. To obtain the proper statistical output, several millions of calculations are needed to obtain a reliable estimate. Because millions of different scenarios have to be calculated, hydrocode calculations cannot be used for this type of application, but a fast and good engineering solutions is needed. At this moment the Haskins and Cook-model is used for this purpose. To obtain a better estimate for covered explosives and munitions, TNO has developed a new model which is a combination of the shock wave model at high pressure, as described by Haskins and Cook, in combination with the expanding shock wave model of Green. This combined model gives a better fit with the experimental values for explosives response calculations, using the same critical energy fluence values for covered as well as for bare explosives. In this paper the theory is explained and results of the calculations for several bare and covered explosives will be presented. To show this, the results will be compared with the experimental values from literature for composition B, Composition B-3 and PBX-9404.

  8. Electrochemical Sensor for Explosives Precursors’ Detection in Water

    Directory of Open Access Journals (Sweden)

    Cloé Desmet

    2017-03-01

    Full Text Available Although all countries are intensifying their efforts against terrorism and increasing their mutual cooperation, terrorist bombing is still one of the greatest threats to society. The discovery of hidden bomb factories is of primary importance in the prevention of terrorism activities. Criminals preparing improvised explosives (IE use chemical substances called precursors. These compounds are released in the air and in the waste water during IE production. Tracking sources of precursors by analyzing air or wastewater can then be an important clue for bomb factories’ localization. We are reporting here a new multiplex electrochemical sensor dedicated to the on-site simultaneous detection of three explosive precursors, potentially used for improvised explosive device preparation (hereafter referenced as B01, B08, and B15, for security disclosure reasons and to avoid being detrimental to the security of the counter-explosive EU action. The electrochemical sensors were designed to be disposable and to combine ease of use and portability in a screen-printed eight-electrochemical cell array format. The working electrodes were modified with different electrodeposited metals: gold, palladium, and platinum. These different coatings giving selectivity to the multi-sensor through a “fingerprint”-like signal subsequently analyzed using partial least squares-discriminant analysis (PLS-DA. Results are given regarding the detection of the three compounds in a real environment and in the presence of potentially interfering species.

  9. Development of mine explosion ground truth smart sensors

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Steven R. [Rocky Mountain Geophysics, Inc., Los Alamos, NM (United States); Harben, Phillip E. [Rocky Mountain Geophysics, Inc., Los Alamos, NM (United States); Jarpe, Steve [Jarpe Data Solutions, Prescott, AZ (United States); Harris, David B. [Deschutes Signal Processing, Maupin, OR (United States)

    2015-09-14

    Accurate seismo-acoustic source location is one of the fundamental aspects of nuclear explosion monitoring. Critical to improved location is the compilation of ground truth data sets for which origin time and location are accurately known. Substantial effort by the National Laboratories and other seismic monitoring groups have been undertaken to acquire and develop ground truth catalogs that form the basis of location efforts (e.g. Sweeney, 1998; Bergmann et al., 2009; Waldhauser and Richards, 2004). In particular, more GT1 (Ground Truth 1 km) events are required to improve three-dimensional velocity models that are currently under development. Mine seismicity can form the basis of accurate ground truth datasets. Although the location of mining explosions can often be accurately determined using array methods (e.g. Harris, 1991) and from overhead observations (e.g. MacCarthy et al., 2008), accurate origin time estimation can be difficult. Occasionally, mine operators will share shot time, location, explosion size and even shot configuration, but this is rarely done, especially in foreign countries. Additionally, shot times provided by mine operators are often inaccurate. An inexpensive, ground truth event detector that could be mailed to a contact, placed in close proximity (< 5 km) to mining regions or earthquake aftershock regions that automatically transmits back ground-truth parameters, would greatly aid in development of ground truth datasets that could be used to improve nuclear explosion monitoring capabilities. We are developing an inexpensive, compact, lightweight smart sensor unit (or units) that could be used in the development of ground truth datasets for the purpose of improving nuclear explosion monitoring capabilities. The units must be easy to deploy, be able to operate autonomously for a significant period of time (> 6 months) and inexpensive enough to be discarded after useful operations have expired (although this may not be part of our business

  10. Sensitivity to friction for primary explosives.

    Science.gov (United States)

    Matyáš, Robert; Šelešovský, Jakub; Musil, Tomáš

    2012-04-30

    The sensitivity to friction for a selection of primary explosives has been studied using a small BAM friction apparatus. The probit analysis was used for the construction of a sensitivity curve for each primary explosive tested. Two groups of primary explosives were chosen for measurement (a) the most commonly used industrially produced primary explosives (e.g. lead azide, tetrazene, dinol, lead styphnate) and (b) the most produced improvised primary explosives (e.g. triacetone triperoxide, hexamethylenetriperoxide diamine, mercury fulminate, acetylides of heavy metals). A knowledge of friction sensitivity is very important for determining manipulation safety for primary explosives. All the primary explosives tested were carefully characterised (synthesis procedure, shape and size of crystals). The sensitivity curves obtained represent a unique set of data, which cannot be found anywhere else in the available literature. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Spot test kit for explosives detection

    Science.gov (United States)

    Pagoria, Philip F; Whipple, Richard E; Nunes, Peter J; Eckels, Joel Del; Reynolds, John G; Miles, Robin R; Chiarappa-Zucca, Marina L

    2014-03-11

    An explosion tester system comprising a body, a lateral flow membrane swab unit adapted to be removeably connected to the body, a first explosives detecting reagent, a first reagent holder and dispenser operatively connected to the body, the first reagent holder and dispenser containing the first explosives detecting reagent and positioned to deliver the first explosives detecting reagent to the lateral flow membrane swab unit when the lateral flow membrane swab unit is connected to the body, a second explosives detecting reagent, and a second reagent holder and dispenser operatively connected to the body, the second reagent holder and dispenser containing the second explosives detecting reagent and positioned to deliver the second explosives detecting reagent to the lateral flow membrane swab unit when the lateral flow membrane swab unit is connected to the body.

  12. The IASPEI Reference Event List to Support 3D Velocity Model Validation Studies

    Science.gov (United States)

    Bondar, I.; Storchak, D. A.

    2013-05-01

    The IASPEI Reference Event List (Ground Truth database) maintained and hosted by the International Seismological Centre (ISC) on behalf of the IASPEI became an indispensable tool for the validation of 3D seismic velocity models. The Ground Truth database is regularly updated and currently consists of some 7,600 GT0-5 events (earthquakes, chemical and nuclear explosions). Recently the CTBTO has launched a global initiative to facilitate the development of the Regional Seismic Travel Time (RSTT) velocity model on a global scale by forming regional expert groups. We make a concentrated effort to increase the number and the coverage of ground truth events in Latin America. To further support the RSTT development and validation studies, the ISC has developed a version of its location software to accommodate local and regional travel-time predictions provided by the RSTT software package. The RSTT-enabled ISC locator is made available through the ISC website.

  13. Electron microprobe chemical U-Th-Pb and La-ICP-MS U-Pb dating of multiple hydrothermal and metamorphic events recorded in minerals of the Lagoa Real uraniferous albitites (Brazil)

    Energy Technology Data Exchange (ETDEWEB)

    Chaves, Alexandre de Oliveira, E-mail: alochaves@yahoo.com.b [Universidade Federal do Espirito Santo (UFES), Vitoria (Brazil); Tubrett, Michael [Memorial University of Newfoundland (Canada); Avelar, Simone Cristina Pires; Rios, Francisco Javier; Neves, Jose Marques Correia; Alves, James Vieira; Fuzikawa, Kazuo; Prates, Sonia Pinto [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Sgarbi, Geraldo Norberto Chaves [Universidade Federal de Minas Gerais (IG/UFMG), Belo Horizonte (Brazil). Inst. de Geociencias; Matos, Evando Carele de [Industrias Nucleares do Brasil, Caetite, BA (Brazil)

    2009-05-15

    Lagoa Real uraniferous albitites are rocks which went through multiple modifications after formation. Electron microprobe chemical U-Th-Pb and LA-ICP-MS U-Pb dating of minerals of albitites reveal protolith (U-bearing sodic syenites) crystallization and isochemical metamorphism at ca. 2.0-1.9 Ga during the final stages of the Orosirian orogenic event, when the first generation of uraninites was formed. Multiple uranium and lead mobilization promoted by at least five hydrothermal events (ca. 1.7 Ga, ca. 1.5 Ga, ca. 1.3 Ga, ca. 1.1 Ga, and ca. 1.0 Ga) was detected in the albitites. A probable formation of a second uraninite group and/or resetting of UPb clock of older uraninites during the Brasiliano orogenic event at ca. 0.5 Ga also took place.(author)

  14. Ranchero Explosive Pulsed Power Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Goforth, J.H.; Atchison, W.L.; Deninger, W.J.; Fowler, C.M.; Herrera, D.H.; King, J.C.; Lopez, E.A.; Oona, H.; Reinovsky, R.E.; Stokes, J.L.; Sena, F.C.; Tabaka, L.J.; Tasker, D.G.; Torres, D.T.; Lindemuth, I.R.; Faehl, R.J.; Keinigs, R.K.; Taylor, A.J.; Rodriguez, G.; Oro, D.M.; Garcia, O.F.; parker, J.V.; Broste, W.B.

    1999-06-27

    The authors are developing the Ranchero high explosive pulsed power (HEPP) system to power cylindrically imploding solid-density liners for hydrodynamics experiments. The near-term goal is to conduct experiments in the regime pertinent to the Atlas Capacitor bank. That is, they will attempt to implode liners of {approximately}50 g mass at velocities approaching 15 km/sec. The basic building block of the HEPP system is a coaxial generator with a 304.8 mm diameter stator, and an initial armature diameter of 152 mm. The armature is expanded by a high explosive (HE) charge detonated simultaneously along its axis. They have reported a variety of experiments conducted with generator modules 43 cm long and have presented an initial design for hydrodynamic liner experiments. In this paper they give a synopsis of their first system test, and a status report on the development of a generator module that is 1.4 m long.

  15. RANCHERO explosive pulsed power experiments

    CERN Document Server

    Goforth, J H; Armijo, E V; Atchison, W L; Bartos, Yu; Clark, D A; Day, R D; Deninger, W J; Faehl, R J; Fowler, C M; García, F P; García, O F; Herrera, D H; Herrera, T J; Keinigs, R K; King, J C; Lindemuth, I R; López, E; Martínez, E C; Martínez, D; McGuire, J A; Morgan, D; Oona, H; Oro, D M; Parker, J V; Randolph, R B; Reinovsky, R E; Rodríguez, G; Stokes, J L; Sena, F C; Tabaka, L J; Tasker, D G; Taylor, A J; Torres, D T; Anderson, H D; Broste, W B; Johnson, J B; Kirbie, H C

    1999-01-01

    The authors are developing the RANCHERO high explosive pulsed power (HEPP) system to power cylindrically imploding solid-density liners for hydrodynamics experiments. Their near-term goal is to conduct experiments in the regime pertinent to the Atlas capacitor bank. That is, they will attempt to implode liners of ~50 g mass at velocities approaching 15 km/sec. The basic building block of the HEPP system is a coaxial generator with a 304.8 mm diameter stator, and an initial armature diameter of 152 mm. The armature is expanded by a high explosive (HE) charge detonated simultaneously along its axis. The authors have reported a variety of experiments conducted with generator modules 43 cm long and have presented an initial design for hydrodynamic liner experiments. In this paper, they give a synopsis of their first system test, and a status report on the development of a generator module that is 1.4 m long. (6 refs).

  16. Chemical Facility Preparedness: A Comprehensive Approach

    National Research Council Canada - National Science Library

    Pennington, Daniel

    2006-01-01

    .... Many sites are clustered together in densely populated areas. If terrorists cause catastrophic chemical releases or explosions at these key facilities, large numbers of Americans will be put at risk of injury or death...

  17. Studying transient events with Athena

    Science.gov (United States)

    O'Brien, Paul

    2016-07-01

    Athena is the second large mission selected in the ESA Cosmic Vision plan. With its large collecting area, high spectral-energy resolution (X-IFU instrument) and impressive grasp (WFI instrument), Athena will truly revolutionise X-ray astronomy. The most prodigious sources of high-energy photons are often transitory in nature. Athena will provide the sensitivity and spectral resolution coupled with rapid response to enable the study of the dynamic sky. Potential sources include: distant Gamma-Ray Bursts to probe the reionisation epoch and find 'missing' baryons in the cosmic web; tidal disruption events to reveal dormant supermassive and intermediate-mass black holes; and supernova explosions to understand progenitors and their environments. I will illustrate Athena's capabilities and show how it will be able to constrain the nature of explosive events.

  18. Explosives Removal from Munitions Wastewaters

    Science.gov (United States)

    1975-01-01

    Rohm and Haas Company, Philadelphia, Pa., 19105 2 Background Generally, pollation in munitions plant waste water stems from washing and steam cleaning...290131 EXPLOSIVES REMOVAL FROM MUNITIONS WST- WATERS B. W. STEVENS, R. P. MCDONNELL ROHM. AND HAAS CO?*ANY, PHILAD2ELPHIA, PENNSYLVANIA R. K. PXDREN...operations. Waste water from a typical TNT manufacturing J21 plant may contain from 40 to 120 ppm of TNT and lesser aimounts of 2,4, DNT. K. Waste

  19. Shell and explosive hydrogen burning

    CERN Document Server

    Boeltzig, A; Cavanna, F; Cristallo, S; Davinson, T; Depalo, R; deBoer, R J; Di Leva, A; Ferraro, F; Imbriani, G; Marigo, P; Terrasi, F; Wiescher, M

    2016-01-01

    The nucleosynthesis of light elements, from helium up to silicon, mainly occurs in Red Giant and Asymptotic Giant Branch stars and Novae. The relative abundances of the synthesized nuclides critically depend on the rates of the nuclear processes involved, often through non-trivial reaction chains, combined with complex mixing mechanisms. In this review, we summarize the contributions made by LUNA experiments in furthering our understanding of nuclear reaction rates necessary for modeling nucleosynthesis in AGB stars and Novae explosions.

  20. Nuclear Explosions 1945-1998

    Energy Technology Data Exchange (ETDEWEB)

    Bergkvist, Nils-Olov; Ferm, Ragnhild

    2000-07-01

    The main part of this report is a list of nuclear explosions conducted by the United States, the Soviet Union, the United Kingdom, France, China, India and Pakistan in 1945-98. The list includes all known nuclear test explosions and is compiled from a variety of sources including officially published information from the USA, Russia and France. The details given for each explosion (date, origin time, location, yield, type, etc.) are often compiled from more than one source because the individual sources do not give complete information. The report includes a short background to nuclear testing and provides brief information on the Comprehensive Nuclear-Test-Ban Treaty and the verification regime now being established to verify compliance with the treaty. It also summarizes nuclear testing country by country. The list should be used with some caution because its compilation from a variety of sources means that some of the data could be incorrect. This report is the result of cooperation between the Defence Research Establishment (FOA) and the Stockholm International Peace Research Institute (SIPRI)

  1. Gamma-ray line measurements from supernova explosions

    Science.gov (United States)

    Diehl, Roland

    2017-02-01

    Gamma ray lines are expected to be emitted as part of the afterglow of supernova explosions, because radioactive decay of freshly synthesised nuclei occurs. Significant radioactive gamma ray line emission is expected from 56Ni and 44Ti decay on time scales of the initial explosion (56Ni, τ ~days) and the young supernova remnant (44Ti,τ ~90 years). Less specific, and rather informative for the supernova population as a whole, are lessons from longer lived isotopes such as 26Al and 60Fe. From isotopes of elements heavier than iron group elements, any interesting gamma-ray line emission is too faint to be observable. Measurements with space-based gamma-ray telescopes have obtained interesting gamma ray line emissions from two core collapse events, Cas A and SN1987A, and one thermonuclear event, SN2014J. We discuss INTEGRAL data from all above isotopes, including all line and continuum signatures from these two objects, and the surveys for more supernovae, that have been performed by gamma ray spectrometry. Our objective here is to illustrate what can be learned from gamma-ray line emission properties about the explosions and their astrophysics.

  2. Water-soaked evidence: detectability of explosive traces after immersion in water.

    Science.gov (United States)

    Kamyshny, Alexander; Magdassi, Shlomo; Avissar, Yaniv; Almog, Joseph

    2003-03-01

    Various factors governing the detectability of explosive traces after being soaked in water were studied. The variables are: the type of the surface (surfaces liable to be found in aircraft were chosen), the type of explosive, the type of water (tap or seawater), and movement of the immersed surface in the water. The maximal immersion times (tmax) after which explosive detection was possible were evaluated. This datum was found to depend on the type of explosive (one of the important factors is solubility in water), the surface material and the environmental conditions (tap or seawater movement). Detection of PETN on high-density polyethylene, linoleum, glass and aluminum, by the chemical Explosive Testing Kit (ETK), was possible even after a month of soaking in seawater. In addition, it has been found that movement of bulk water around the samples with deposited explosives considerably decreases tmax values. It is, therefore, recommended to retrieve samples for explosive analysis as soon as possible and in areas where the currents of water is minimal.

  3. Fault tree analysis of fire and explosion accidents for dual fuel (diesel/natural gas) ship engine rooms

    Science.gov (United States)

    Guan, Yifeng; Zhao, Jie; Shi, Tengfei; Zhu, Peipei

    2016-09-01

    In recent years, China's increased interest in environmental protection has led to a promotion of energy-efficient dual fuel (diesel/natural gas) ships in Chinese inland rivers. A natural gas as ship fuel may pose dangers of fire and explosion if a gas leak occurs. If explosions or fires occur in the engine rooms of a ship, heavy damage and losses will be incurred. In this paper, a fault tree model is presented that considers both fires and explosions in a dual fuel ship; in this model, dual fuel engine rooms are the top events. All the basic events along with the minimum cut sets are obtained through the analysis. The primary factors that affect accidents involving fires and explosions are determined by calculating the degree of structure importance of the basic events. According to these results, corresponding measures are proposed to ensure and improve the safety and reliability of Chinese inland dual fuel ships.

  4. Medical consequences of suicide bombing mass casualty incidents: the impact of explosion setting on injury patterns.

    Science.gov (United States)

    Kosashvili, Yona; Loebenberg, Mark I; Lin, Guy; Peleg, Kobi; Zvi, Feigenberg; Kluger, Yoram; Blumenfeld, Amir

    2009-07-01

    The increase in the incidence of suicide bombings on urban civilian populations in the recent years necessitates a better understanding of the related epidemiology in order to improve the outcome of future casualties. To characterise the epidemiology of mass casualty incidents following suicide explosions in relation to the surrounding settings. This study presents an analysis of the immediate medical consequences of 12 consecutive multiple casualty incidents (MCI's). Both pre-hospital and in-hospital data was assessed for each event including EMS evacuation times, types of injuries, body regions involved, Emergency Department (ED) triage, ED interventions and surgical procedures performed. The average arrival time of the first ambulance to the scene was 6.8+/-2.3 min. The first "urgent" patient was evacuated in average of 7.6+/-5.3 min later, while the last "urgent" patient was evacuated 27.8+/-7.9 min after the explosion. Explosions that occurred in buses had the worst rates of overall mortality (21.2%). However, those who survived closed space explosions suffered from the highest number of severe and moderate (ISS>8) injuries (22.9%). Casualties in this group underwent the largest number of both Emergency Room and Surgical interventions. Of the three settings, open space explosions resulted in the largest numbers of casualties with the smallest percentage of severe injuries or death. MCIs resulting from suicide explosions can be classified according to the setting of the event since each group was found to have distinct epidemiological characteristics.

  5. Trends in Nuclear Explosion Monitoring Research & Development - A Physics Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Maceira, Monica [Los Alamos National Laboratory; Blom, Philip Stephen [Los Alamos National Laboratory; Maccarthy, Jonathan K. [Los Alamos National Laboratory; Marcillo, Omar Eduardo [Los Alamos National Laboratory; Euler, Garrett Gene [Los Alamos National Laboratory; Begnaud, Michael Lee [Los Alamos National Laboratory; Ford, Sean R. [Lawrence Livermore National Laboratory; Pasyanos, Michael E. [Lawrence Livermore National Laboratory; Orris, Gregory J. [Naval Research Laboratory; Foxe, Michael P. [Pacific Northwest National Laboratory; Arrowsmith, Stephen J. [Sandia National Laboratory; Merchant, B. John [Sandia National Laboratory; Slinkard, Megan E. [Sandia National Laboratory

    2017-06-01

    This document entitled “Trends in Nuclear Explosion Monitoring Research and Development – A Physics Perspective” reviews the accessible literature, as it relates to nuclear explosion monitoring and the Comprehensive Nuclear-Test-Ban Treaty (CTBT, 1996), for four research areas: source physics (understanding signal generation), signal propagation (accounting for changes through physical media), sensors (recording the signals), and signal analysis (processing the signal). Over 40 trends are addressed, such as moving from 1D to 3D earth models, from pick-based seismic event processing to full waveform processing, and from separate treatment of mechanical waves in different media to combined analyses. Highlighted in the document for each trend are the value and benefit to the monitoring mission, key papers that advanced the science, and promising research and development for the future.

  6. Kamchatkan Volcanoes Explosive Eruptions in 2014 and Danger to Aviation

    Science.gov (United States)

    Girina, Olga; Manevich, Alexander; Melnikov, Dmitry; Demyanchuk, Yury; Nuzhdaev, Anton; Petrova, Elena

    2015-04-01

    There are 30 active volcanoes in the Kamchatka, and several of them are continuously active. In 2014, three of the Kamchatkan volcanoes - Sheveluch, Karymsky and Zhupanovsky - had strong and moderate explosive eruptions. Moderate gas-steam activity was observing of Klyuchevskoy, Bezymianny, Avachinsky, Koryaksky, Gorely, Mutnovsky and other volcanoes. Strong explosive eruption of volcanoes is the most dangerous for aircraft because in a few hours or days in the atmosphere and the stratosphere can produce about several cubic kilometers of volcanic ash and aerosols. Ash plumes and the clouds, depending on the power of the eruption, the strength and wind speed, can travel thousands of kilometers from the volcano for several days, remaining hazardous to aircraft, as the melting temperature of small particles of ash below the operating temperature of jet engines. The eruptive activity of Sheveluch Volcano began since 1980 (growth of the lava dome) and is continuing at present. Strong explosive events of the volcano occurred in 2014: on January 08 and 12, May 12, September 24, October 02 and 28, November 16, 22 and 26, and December 05, 17, 26 and 29: ash plumes rose up to 9-12 km a.s.l. and extended more 900 km to the eastern and western directions of the volcano. Ashfalls occurred at Klyuchi Village (on January 12, June 11, and November 16). Activity of the volcano was dangerous to international and local aviation. Karymsky volcano has been in a state of explosive eruption since 1996. The moderate ash explosions of this volcano were noting during 2014: from March 24 till April 02; and from September 03 till December 10. Ash plumes rose up to 5 km a.s.l. and extended more 300 km mainly to the eastern directions of the volcano. Activity of the volcano was dangerous to local aviation. Explosive eruption of Zhupanovsky volcano began on June 06, 2014 and continues in January 2015 too. Ash explosions rose up to 8-10 km a.s.l. on June 19, September 05 and 07, October 11

  7. Chemistry Resolved Kinetic Flow Modeling of TATB Based Explosives

    Energy Technology Data Exchange (ETDEWEB)

    Vitello, P A; Fried, L E; Howard, W M; Levesque, G; Souers, P C

    2011-07-21

    Detonation waves in insensitive, TATB based explosives are believed to have multi-time scale regimes. The initial burn rate of such explosives has a sub-microsecond time scale. However, significant late-time slow release in energy is believed to occur due to diffusion limited growth of carbon. In the intermediate time scale concentrations of product species likely change from being in equilibrium to being kinetic rate controlled. They use the thermo-chemical code CHEETAH linked to an ALE hydrodynamics code to model detonations. They term their model chemistry resolved kinetic flow as CHEETAH tracks the time dependent concentrations of individual species in the detonation wave and calculates EOS values based on the concentrations. A HE-validation suite of model simulations compared to experiments at ambient, hot, and cold temperatures has been developed. They present here a new rate model and comparison with experimental data.

  8. ATEX explosive atmospheres : risk assessment, control and compliance

    CERN Document Server

    Jespen, Torben

    2016-01-01

    This book details how safety (i.e. the absence of unacceptable risks) is ensured in areas where potentially explosive atmospheres (ATEX) can arise. The book also offers readers essential information on how to comply with the newest (April 2016) EU legislation when the presence of ATEX cannot be avoided. By presenting general guidance on issues arising out of the EU ATEX legislation – especially on zone classification, explosion risk assessment, equipment categorization, Ex-marking and related technical/chemical aspects – the book provides equipment manufacturers, responsible employers, and others with the essential knowledge they need to be able to understand the different – and often complicated – aspects of ATEX and to implement the necessary safety precautions. As such, it represents a valuable resource for all those concerned with maintaining high levels of safety in ATEX environments.

  9. The role of turbulence in explosive magma-water mixing

    Science.gov (United States)

    Mastin, L. G.; Walder, J. S.; Stern, L. A.

    2003-12-01

    Juvenile tephra from explosive hydromagmatic eruptions differs from that of dry magmatic eruptions by its fine average grain size and highly variable vesicularity. These characteristics are generally interpreted to indicate that fragmentation, which occurs in dry magmas by bubble growth, is supplemented in hydromagmatic eruptions by quench-fracturing. Quench fragmentation is thought to accelerate heat transfer to water, driving violent steam expansion and increasing eruptive violence. Although some observed hydromagmatic events (e.g. at Surtsey) are indeed violent, others (e.g. quiescent entry of lava into the ocean at Kilauea) are not. We suggest that the violence of magma-water mixing and the grain size and dispersal of hydromagmatic tephras are controlled largely by the turbulence of magma-water mixing. At Surtsey, fine-grained, widely dispersed hydromagmatic tephras were produced primarily during continuous uprush events in which turbulent jets of magma and gas passed through shallow water (Thorarinsson, 1967). During Kilauea's current eruption, videos show generation of fine-grained tephras when turbulent jets of magma, steam, and seawater exited through skylights at the coastline. Turbulence intensity, or the fraction of total jet kinetic energy contained in fine-scale turbulent velocity oscillations, has long been known to control the scale of atomization in spray nozzles and the rate of heat transfer and chemical reaction in fuel injectors. We hypothesize that turbulence intensity also influences grain size and heat transfer rate in magma-water mixing, though such processes are complicated by boiling (in water) and quench fracturing (in magma). We are testing this hypothesis in experiments involving turbulent injection of water (a magma analog) into liquid nitrogen (a water analog). We also suggest that turbulent mixing influences relative proportions of magma and water in hydromagmatic eruptions. Empirical studies indicate that pressure-neutral turbulent

  10. The ALMA View of the OMC1 Explosion in Orion

    Energy Technology Data Exchange (ETDEWEB)

    Bally, John; Youngblood, Allison [Astrophysical and Planetary Sciences Department University of Colorado, UCB 389 Boulder, Colorado 80309 (United States); Ginsburg, Adam [ESO Headquarters Karl-Schwarzschild-Str. 2 D-85748, Garching bei Munchen (Germany); Arce, Hector [Department of Astronomy Steinbach Hall, 52 Hillhouse Avenue, Yale University, New Haven, CT 06511 (United States); Eisner, Josh [Steward Observatory University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Zapata, Luis [Instituto de Radioastronomía y Astrofísíca, UNAM Apdo. Postal 3-72 (Xangari), 58089 Morelia, Michoacán, México (Mexico); Zinnecker, Hans, E-mail: john.bally@colorado.edu [Deutsches SOFIA Institut (DSI) University of Stuttgart, Pfaffenwaldring 29, D-70569 (Germany)

    2017-03-01

    Most massive stars form in dense clusters where gravitational interactions with other stars may be common. The two nearest forming massive stars, the BN object and Source I, located behind the Orion Nebula, were ejected with velocities of ∼29 and ∼13 km s{sup −1} about 500 years ago by such interactions. This event generated an explosion in the gas. New ALMA observations show in unprecedented detail, a roughly spherically symmetric distribution of over a hundred {sup 12}CO J = 2−1 streamers with velocities extending from V {sub LSR} = −150 to +145 km s{sup −1}. The streamer radial velocities increase (or decrease) linearly with projected distance from the explosion center, forming a “Hubble Flow” confined to within 50″ of the explosion center. They point toward the high proper-motion, shock-excited H{sub 2} and [Fe ii] “fingertips” and lower-velocity CO in the H{sub 2} wakes comprising Orion's “fingers.” In some directions, the H{sub 2} “fingers” extend more than a factor of two farther from the ejection center than the CO streamers. Such deviations from spherical symmetry may be caused by ejecta running into dense gas or the dynamics of the N -body interaction that ejected the stars and produced the explosion. This ∼10{sup 48} erg event may have been powered by the release of gravitational potential energy associated with the formation of a compact binary or a protostellar merger. Orion may be the prototype for a new class of stellar explosiozn responsible for luminous infrared transients in nearby galaxies.

  11. Exploring the explosive-effusive transition using permanent ultraviolet cameras

    Science.gov (United States)

    Delle Donne, D.; Tamburello, G.; Aiuppa, A.; Bitetto, M.; Lacanna, G.; D'Aleo, R.; Ripepe, M.

    2017-06-01

    Understanding the mechanisms that cause effusive eruptions is the key to mitigating their associated hazard. Here we combine results from permanent ultraviolet (UV) cameras, and from other geophysical observations (seismic very long period, thermal, and infrasonic activity), to characterize volcanic SO2 flux regime in the period prior, during, and after Stromboli's August-November 2014 effusive eruption. We show that, in the 2 months prior to effusion onset, the SO2 flux levels are 2 times average level. We explain this anomalously high SO2 regime as primarily determined by venting of rapidly rising, pressurized SO2-rich gas pockets produced by strombolian explosions being more frequent and intense than usual. We develop a procedure to track (and count), in the UV camera record, the SO2 flux pulses produced by individual explosions and puffing activity (active degassing). We find that these SO2 pulses are far more numerous (67 ± 47 events per hour) before the effusion onset than during normal activity (20 ± 15 events per hour). This observation, combined with geophysical evidence, demonstrates an elevated gas bubble supply to the shallow conduits, causing elevated explosive and puffing activity. This increase (≥0.1 m3 s-1) in magma transport rate in the north-east feeding conduits finally triggers effusion onset. Active degassing remains elevated also during the effusive phase, supporting the persistence of explosive and puffing activity during the effusive eruption, deep in the volcanic conduit. Our results demonstrate that permanent UV cameras can valuably contribute to monitoring at high-sampling frequency gas dynamics and fluxes, thus opening the way to direct comparison with more established geophysical observations.

  12. Experiments To Demonstrate Chemical Process Safety Principles.

    Science.gov (United States)

    Dorathy, Brian D.; Mooers, Jamisue A.; Warren, Matthew M.; Mich, Jennifer L.; Murhammer, David W.

    2001-01-01

    Points out the need to educate undergraduate chemical engineering students on chemical process safety and introduces the content of a chemical process safety course offered at the University of Iowa. Presents laboratory experiments demonstrating flammability limits, flash points, electrostatic, runaway reactions, explosions, and relief design.…

  13. Haz-Mat Refresher: Chemical Precautions

    Science.gov (United States)

    Caliendo, Louis A.

    2012-01-01

    It is important that first responders remain aware of the possible hazards resulting from chemical accidents or the intentional use of chemicals in destructive devices. Chemical components can be utilized in the manufacturing of improvised explosive devices (IEDs), can enhance the effect of a more conventional device, or can pose hazards based on…

  14. Atmospheric pressure chemical ionization of explosives induced by soft X-radiation in ion mobility spectrometry: mass spectrometric investigation of the ionization reactions of drift gasses, dopants and alkyl nitrates.

    Science.gov (United States)

    Riebe, Daniel; Erler, Alexander; Ritschel, Thomas; Beitz, Toralf; Löhmannsröben, Hans-Gerd; Beil, Andreas; Blaschke, Michael; Ludwig, Thomas

    2016-08-01

    A promising replacement for the radioactive sources commonly encountered in ion mobility spectrometers is a miniaturized, energy-efficient photoionization source that produce the reactant ions via soft X-radiation (2.8 keV). In order to successfully apply the photoionization source, it is imperative to know the spectrum of reactant ions and the subsequent ionization reactions leading to the detection of analytes. To that end, an ionization chamber based on the photoionization source that reproduces the ionization processes in the ion mobility spectrometer and facilitates efficient transfer of the product ions into a mass spectrometer was developed. Photoionization of pure gasses and gas mixtures containing air, N2 , CO2 and N2 O and the dopant CH2 Cl2 is discussed. The main product ions of photoionization are identified and compared with the spectrum of reactant ions formed by radioactive and corona discharge sources on the basis of literature data. The results suggest that photoionization by soft X-radiation in the negative mode is more selective than the other sources. In air, adduct ions of O2- with H2 O and CO2 were exclusively detected. Traces of CO2 impact the formation of adduct ions of O2- and Cl- (upon addition of dopant) and are capable of suppressing them almost completely at high CO2 concentrations. Additionally, the ionization products of four alkyl nitrates (ethylene glycol dinitrate, nitroglycerin, erythritol tetranitrate and pentaerythritol tetranitrate) formed by atmospheric pressure chemical ionization induced by X-ray photoionization in different gasses (air, N2 and N2 O) and dopants (CH2 Cl2 , C2 H5 Br and CH3 I) are investigated. The experimental studies are complemented by density functional theory calculations of the most important adduct ions of the alkyl nitrates (M) used for their spectrometric identification. In addition to the adduct ions [M + NO3 ]- and [M + Cl]- , adduct ions such as [M + N2 O2 ]- , [M + Br]- and [M

  15. 75 FR 70291 - Commerce in Explosives; List of Explosive Materials (2010R-27T)

    Science.gov (United States)

    2010-11-17

    ... hydrocarbons. Explosive organic nitrate mixtures. Explosive powders. F Flash powder. Fulminate of mercury. Fulminate of silver. Fulminating gold. Fulminating mercury. Fulminating platinum. Fulminating silver. G... fulminate. Mercury oxalate. Mercury tartrate. Metriol trinitrate. Minol-2 . MMAN ; methylamine nitrate...

  16. 77 FR 58410 - Commerce in Explosives; List of Explosive Materials (2012R-10T)

    Science.gov (United States)

    2012-09-20

    ... hydrocarbons. Explosive organic nitrate mixtures. Explosive powders. F Flash powder. ] Fulminate of mercury. Fulminate of silver. Fulminating gold. Fulminating mercury. Fulminating platinum. Fulminating silver. G... fulminate. Mercury oxalate. Mercury tartrate. Metriol trinitrate. Minol-2 . MMAN ; methylamine nitrate...

  17. Shock Initiation of Damaged Explosives

    Energy Technology Data Exchange (ETDEWEB)

    Chidester, S K; Vandersall, K S; Tarver, C M

    2009-10-22

    Explosive and propellant charges are subjected to various mechanical and thermal insults that can increase their sensitivity over the course of their lifetimes. To quantify this effect, shock initiation experiments were performed on mechanically and thermally damaged LX-04 (85% HMX, 15% Viton by weight) and PBX 9502 (95% TATB, 5% Kel-F by weight) to obtain in-situ manganin pressure gauge data and run distances to detonation at various shock pressures. We report the behavior of the HMX-based explosive LX-04 that was damaged mechanically by applying a compressive load of 600 psi for 20,000 cycles, thus creating many small narrow cracks, or by cutting wedge shaped parts that were then loosely reassembled, thus creating a few large cracks. The thermally damaged LX-04 charges were heated to 190 C for long enough for the beta to delta solid - solid phase transition to occur, and then cooled to ambient temperature. Mechanically damaged LX-04 exhibited only slightly increased shock sensitivity, while thermally damaged LX-04 was much more shock sensitive. Similarly, the insensitive explosive PBX 9502 was mechanically damaged using the same two techniques. Since PBX 9502 does not undergo a solid - solid phase transition but does undergo irreversible or 'rachet' growth when thermally cycled, thermal damage to PBX 9502 was induced by this procedure. As for LX-04, the thermally damaged PBX 9502 demonstrated a greater shock sensitivity than mechanically damaged PBX 9502. The Ignition and Growth reactive flow model calculated the increased sensitivities by igniting more damaged LX-04 and PBX 9502 near the shock front based on the measured densities (porosities) of the damaged charges.

  18. Explosives detection technology for commercial aviation security

    Science.gov (United States)

    Schafrik, Robert E.

    1994-03-01

    The threat posed to commercial aviation by small, concealed plastic explosives is particularly onerous. Small amounts of these highly energetic explosives are difficult to reliably detect using current technologies. But they can cause significant damage to an aircraft that can result in the destruction of the aircraft, resulting in loss of life. The key issues regarding explosive detection technologies include: What methods can detect plastic explosives? How do these methods perform in practice? How can the different methods be best employed to counter the terrorist threat?

  19. Theoretical basis of explosion effects using al - granules in bulk explosives

    OpenAIRE

    Dambov, Risto; Nikolic, Miroslav; Dambov, Ilija; Cacarov, Vladimir

    2013-01-01

    Use of bulk explosives such as AN-FO, heavy AN-FO, SLLURY and various Emulsions significantly improves explosive energy efficiency in the rock massif. Many operating engineers have the opportunity to examine and modify the technical characteristics of explosives and technologists especially, in the production of explosives where the main goal is improvement, the energy capacity by adding various components. The question is when is technically and economically most suitable to use ...

  20. Explosive transition in amorphous microwire

    Science.gov (United States)

    Borisenko, I. Yu.; Tulin, V. A.

    2017-11-01

    An amorphous microwire in a glass shell offers a quick thermal response and can be rapidly heated to the crystallization point. When heated by a current pulse with a small amplitude and duration, the wire passes from the amorphous to microcrystalline state. The crystallization of the amorphous state may represent a slow or explosive process depending on the parameters of the pulse. In the latter case, the emission of electromagnetic waves (flash of light) and a sharp rise in the resistance are observed. The rate of propagation of the crystallization front in our experiments has been found to be about 1 m/s.

  1. Explosives detection using nanoporous coatings

    Science.gov (United States)

    Pina, María P.; Pellejero, Ismael; Urbiztondo, Miguel; Sesé, Javier; Santamaría, J.

    2011-06-01

    Zeolite-coated cantilevers provided with internal heating elements have been developed and used for the selective detection of nitroderivates, in particular o-nitrotoluene as an example of an explosive-related molecule. In particular, Co exchanged commercial BEA zeolites have been deployed of rectangular Si cantilevers by microdropping technique. In particular, two different strategies have been demonstrated to increase the zeolite modified cantilevers performance: the sensing coating and the operating temperature. As a result, o-nitrotoluene LOD values below 1 ppm are attained at room temperature conditions; whereas the interference of toluene at concentrations below 1000 ppm is completely suppressed by heating the cantilever.

  2. The gas dynamics of explosions

    CERN Document Server

    Lee,\tJohn H S

    2016-01-01

    Explosions, and the non-steady shock propagation associated with them, continue to interest researchers working in different fields of physics and engineering (such as astrophysics and fusion). Based on the author's course in shock dynamics, this book describes the various analytical methods developed to determine non-steady shock propagation. These methods offer a simple alternative to the direct numerical integration of the Euler equations and offer a better insight into the physics of the problem. Professor Lee presents the subject systematically and in a style that is accessible to graduate students and researchers working in shock dynamics, combustion, high-speed aerodynamics, propulsion and related topics.

  3. Power of TATP based explosives.

    Science.gov (United States)

    Matyás, Robert; Selesovský, Jakub

    2009-06-15

    The power of various explosive mixtures based on triacetone triperoxide (3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexoxonane, TATP), ammonimum nitrate (AN), urea nitrate (UrN) and water (W), namely TATP/AN, oil/AN, TATP/UrN, TATP/W and TATP/AN/W, was studied using the ballistic mortar test. The ternary mixtures of TATP/AN/W have relatively high power in case of the low water contents. Their power decrease significantly with increasing the water content in the mixture to more than 30%.

  4. 27 CFR 70.445 - Commerce in explosives.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Commerce in explosives. 70... Cartridges, and Explosives § 70.445 Commerce in explosives. Part 55 of title 27 CFR contains the regulations..., explosives, (b) Permits for users who buy or transport explosives in interstate or foreign commerce, (c...

  5. 29 CFR 1926.902 - Surface transportation of explosives.

    Science.gov (United States)

    2010-07-01

    ... of explosives shall be equipped with a fully charged fire extinguisher, in good condition. An... 29 Labor 8 2010-07-01 2010-07-01 false Surface transportation of explosives. 1926.902 Section 1926... Explosives § 1926.902 Surface transportation of explosives. (a) Transportation of explosives shall meet the...

  6. Personal Chemical Exposure informatics

    Science.gov (United States)

    Chemical Exposure science is the study of human contact with chemicals (from manufacturing facilities, everyday products, waste) occurring in their environments and advances knowledge of the mechanisms and dynamics of events that cause or prevent adverse health outcomes. (adapted...

  7. ANALYSIS OF HAZARDS OF FIRE AND EXPLOSION DURING TREATMENT WITH AMMONIUM SELITRENNOE EXPLOSIVES

    OpenAIRE

    Luchko, Ivan Andriiovych; Pashkov, Anatolii Pavlovych

    2016-01-01

    Dangerous factors at the handling ammonium nitrate explosives are covered. Dependence of influence of critical diameter for detonation on degree of compaction of the explosives is specified, causes of self-ignition of liquid explosive mixes are determined and measures according to their elimination are recommended.

  8. A structured approach to forensic study of explosions: The TNO Inverse Explosion Analysis tool

    NARCIS (Netherlands)

    Voort, M.M. van der; Wees, R.M.M. van; Brouwer, S.D.; Jagt-Deutekom, M.J. van der; Verreault, J.

    2015-01-01

    Forensic analysis of explosions consists of determining the point of origin, the explosive substance involved, and the charge mass. Within the EU FP7 project Hyperion, TNO developed the Inverse Explosion Analysis (TNO-IEA) tool to estimate the charge mass and point of origin based on observed damage

  9. Chronology of magmatic and biological events during mass extinctions

    Science.gov (United States)

    Schaltegger, U.; Davies, J.; Baresel, B.; Bucher, H.

    2016-12-01

    For mass extinctions, high-precision geochronology is key to understanding: 1) the age and duration of mass extinction intervals, derived from palaeo-biodiversity or chemical proxies in marine sections, and 2) the age and duration of the magmatism responsible for injecting volatiles into the atmosphere. Using high-precision geochronology, here we investigate the sequence of events linked to the Triassic-Jurassic boundary (TJB) and the Permian-Triassic boundary (PTB) mass extinctions. At the TJB, the model of Guex et al. (2016) invokes degassing of early magmas produced by thermal erosion of cratonic lithosphere as a trigger of climate disturbance in the late Rhaetian. We provide geochronological evidence that such early intrusives from the CAMP (Central Atlantic Magmatic Province), predate the end-Triassic extinction event (Blackburn et al. 2013) by 100 kyr (Davies et al., subm.). We propose that these early intrusions and associated explosive volcanism (currently unidentified) initiate the extinction, followed by the younger basalt eruptions of the CAMP. We also provide accurate and precise calibration of the PTB in marine sections in S. China: The PTB and the extinction event coincide within 30 kyr in deep water settings; a hiatus followed by microbial limestone deposition in shallow water settings is of <100 kyr duration. The PTB extinction interval is preceded by up to 300 kyr by the onset of partly alkaline explosive, extrusive and intrusive rocks, which are suggested as the trigger of the mass extinction, rather than the subsequent basalt flows of the Siberian Traps (Burgess and Bowring 2015). From temporal constraints, the main inferences that can be made are: The duration of extinction events is in the x10 kyr range during the initial intrusive activity of a Large Igneous Province, and is postdated by the majority of basalt flows over several 100 kyr. For modeling climate change associated with mass extinctions, volatiles released from the basalt flows may

  10. Type Ia supernovae: explosions and progenitors

    Science.gov (United States)

    Kerzendorf, Wolfgang Eitel

    2011-08-01

    Supernovae are the brightest explosions in the universe. Supernovae in our Galaxy, rare and happening only every few centuries, have probably been observed since the beginnings of mankind. At first they were interpreted as religious omens but in the last half millennium they have increasingly been used to study the cosmos and our place in it. Tycho Brahe deduced from his observations of the famous supernova in 1572, that the stars, in contrast to the widely believe Aristotelian doctrine, were not immutable. More than 400 years after Tycho made his paradigm changing discovery using SN 1572, and some 60 years after supernovae had been identified as distant dying stars, two teams changed the view of the world again using supernovae. The found that the Universe was accelerating in its expansion, a conclusion that could most easily be explained if more than 70% of the Universe was some previously un-identified form of matter now often referred to as `Dark Energy'. Beyond their prominent role as tools to gauge our place in the Universe, supernovae themselves have been studied well over the past 75 years. We now know that there are two main physical causes of these cataclysmic events. One of these channels is the collapse of the core of a massive star. The observationally motivated classes Type II, Type Ib and Type Ic have been attributed to these events. This thesis, however is dedicated to the second group of supernovae, the thermonuclear explosions of degenerate carbon and oxygen rich material and lacking hydrogen - called Type Ia supernovae (SNe Ia). White dwarf stars are formed at the end of a typical star's life when nuclear burning ceases in the core, the outer envelope is ejected, with the degenerate core typically cooling for eternity. Theory predicts that such stars will self ignite when close to 1.38 Msun (called the Chandrasekhar Mass). Most stars however leave white dwarfs with 0.6 Msun, and no star leaves a remnant as heavy as 1.38 M! sun, which suggests

  11. Explosive Activity at Tungurahua Volcano: Analysis of Seismic and Infrasonic Data from 2006 - 2011

    Science.gov (United States)

    Steele, A. L.; Ruiz, M. C.; Lyons, J. J.

    2012-12-01

    Tungurahua is an active, steep-sided andesitic stratovolcano, located in central Ecuador. Historic eruptions are characterized by strong explosions, lava and pyroclastic flows, lahars and tephra fallout. After 75 years of quiescence, a renewed phase of explosive activity began in October 1999. Since, Tungurahua has experienced a series of eruptive cycles, with almost continuous activity separated by only short periods (months) of repose. We apply several statistical techniques to a continuous catalog of over 4500 volcanic explosions, recorded between July 2006 and May 2011. Reduced amplitudes and energies are calculated for each event using four collocated broadband seismic and infrasound sensors. An initial time series analysis isolates 8 phases of activity: Jul-Aug 2006, Feb-Apr 2007, Jul 2007-Feb 2008, Mar 2008-Jun 2009, Jan-Mar 2010, May-Jul 2010, Nov-Dec 2010 and Apr-May 2011. Small temporal changes in the volcanic eruption mechanism across successive episodes are identified by a lack of dependency in event rate auto-correlation and a continuous fluctuation in the proxy b-value of moving-window, frequency-amplitude distributions. We highlight the May-July 2010 episode because it is statistically distinct from the other periods of explosive activity. Peak explosion event rate during this time is approximately six times that of any other episode across the observation period (max ~ 242 events; 31 May 2010), while cumulative daily seismo-acoustic explosion energies are at least an order of magnitude greater. The coefficient of variation (Cv = σ/μ, where; σ is the standard deviation; and μ is the mean repose time of explosions) is used to show a strong clustering of events with time (episodes 1-5 & 7-8 = Cv ~ 2-5) and not representative of a Poisson controlled process. A Cv ~ 13.7 in May-July 2010 (episode 6) further highlights the anomalous nature of activity during this period. The volcano acoustic-seismic ratio (VASR, or η), the ratio of elastic energy

  12. Comparison of Reduced Displacement Potentials from Spe Free Field Measurements: SPE-4PRIME Versus Previous Events

    Science.gov (United States)

    Patton, H. J.; Rougier, E.

    2015-12-01

    Since 2010, the U. S. Department of Energy has funded a series of chemical tests at the National Nuclear Security Site (NNSS) in Climax Stock granite as part of the Source Physics Experiment (SPE) with the aim of gaining a better understanding of the generation and propagation of seismic energy from underground explosions in hard rock media. To date, four tests have been conducted in the same borehole with yields of 100, 1000, 900 and 100 kg at different depths of burials. The nominal scaled depths of burial are 938, 363, 376 and 1556 m/kt1/3 compared to standard containment practices of ~120 m/kt1/3. A quite dense array of free field accelerometers were installed around the borehole, both on and off shot depth. Acceleration data were corrected for shock-generated baseline-shifts, and free field ground velocity waveforms were obtained. This work concentrates on the qualitative analysis of the reduced displacement potentials and the explosion source spectra for the last shot of the series (SPE-4Prime) and the comparison of the obtained results against the previous events. Finally, the results obtained from the experimental data are compared to the Mueller-Murphy empirical explosion model both using the Heard and Ackerman and Denny and Johnson cavity radius scaling laws.

  13. High temperature two component explosive

    Science.gov (United States)

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

    1981-01-01

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

  14. Geotechnical Aspects of Explosive Compaction

    Directory of Open Access Journals (Sweden)

    Mahdi Shakeran

    2016-01-01

    Full Text Available Explosive Compaction (EC is the ground modification technique whereby the energy released from setting off explosives in subsoil inducing artificial earthquake effects, which compact the soil layers. The efficiency of EC predominantly depends on the soil profile, grain size distribution, initial status, and the intensity of energy applied to the soil. In this paper, in order to investigate the geotechnical aspects, which play an important role in performance of EC, a database has been compiled from thirteen-field tests or construction sites around the world, where EC has been successfully applied for modifying soil. This research focuses on evaluation of grain size distribution and initial stability status of deposits besides changes of soil penetration resistance due to EC. Results indicated suitable EC performance for unstable and liquefiable deposits having particle sizes ranging from gravel to silty sand with less than 40% silt content and less than 10% clay content. However, EC is most effective in fine-to-medium sands with a fine content less than 5% and hydraulically deposited with initial relative density ranging from 30% to 60%. Moreover, it has been observed that EC can be an effective method to improve the density, stability, and resistance of the target soils.

  15. LOW OZONE-DEPLETING HALOCARBONS AS TOTAL-FLOOD AGENTS: VOLUME 2. LABORATORY-SCALE FIRE SUPPRESSION AND EXPLOSION PREVENTION TESTING

    Science.gov (United States)

    The report gives results from (1) flame suppression testing of potential Halon-1301 (CF3Br) replacement chemicals in a laboratory cup burner using n-heptane fuel and (2) explosion prevention (inertion) testing in a small-scale explosion sphere using propane and methane as fuels. ...

  16. Stress wave propagationin the site 12 hydraulic/explosive fracturing experiment

    Energy Technology Data Exchange (ETDEWEB)

    Boade, R. R.; Reed, R. P.

    1980-05-01

    The Site 12 experiment was a heavily instrumented field event performed to examine the hydraulic/explosive fracturing concept for preparing an underground oil shale bed for true in situ processing. One of the key phases of this fracturing concept is the blasting operation which involves the insertion and detonation of slurry explosive in a pre-formed system of hydrofractures. To obtain a sound understanding of the nature of the blasting operations, a rather extensive array of stress gages, accelerometers, and time-of-arrival gages was installed in the rock mass in the vacinity of the explosive to monitor the dynamic events initiated by the detonation. These gages provided considerable amounts of information which were useful in evaluating overall results of the experiment. Details of the gage array, of the data, of analysis methods, and of the results and conclusions are considered in the report.

  17. SEM-based methods for the analysis of basaltic ash from weak explosive activity at Etna in 2006 and the 2007 eruptive crisis at Stromboli

    Science.gov (United States)

    Lautze, Nicole C.; Taddeucci, Jacopo; Andronico, Daniele; Cannata, Chiara; Tornetta, Lauretta; Scarlato, Piergiorgio; Houghton, Bruce; Lo Castro, Maria Deborah

    2012-01-01

    We present results from a semi-automated field-emission scanning electron microscope investigation of basaltic ash from a variety of eruptive processes that occurred at Mount Etna volcano in 2006 and at Stromboli volcano in 2007. From a methodological perspective, the proposed techniques provide relatively fast (about 4 h per sample) information on the size distribution, morphology, and surface chemistry of several hundred ash particles. Particle morphology is characterized by compactness and elongation parameters, and surface chemistry data are shown using ternary plots of the relative abundance of several key elements. The obtained size distributions match well those obtained by an independent technique. The surface chemistry data efficiently characterize the chemical composition, type and abundance of crystals, and dominant alteration phases in the ash samples. From a volcanological perspective, the analyzed samples cover a wide spectrum of relatively minor ash-forming eruptive activity, including weak Hawaiian fountaining at Etna, and lava-sea water interaction, weak Strombolian explosions, vent clearing activity, and a paroxysm during the 2007 eruptive crisis at Stromboli. This study outlines subtle chemical and morphological differences in the ash deposited at different locations during the Etna event, and variable alteration patterns in the surface chemistry of the Stromboli samples specific to each eruptive activity. Overall, we show this method to be effective in quantifying the main features of volcanic ash particles from the relatively weak - and yet frequent - explosive activity occurring at basaltic volcanoes.

  18. A false explosion for a real intervention

    CERN Multimedia

    2006-01-01

    Together with their French and Swiss counterparts, the CERN Fire Brigade carried out a spectacular exercise in the LHCb cavern. It was designed to test the coordination of the fire and rescue services of the Organization's two Host States. Inside a temporary medical station set up above ground, the emergency teams deliver medical care to the injured before they are taken to hospital.An accident victim in the underground cavern about to be evacuated. 'I was taking a group of visitors on a tour of the LHCb cavern when there was a huge explosion and I suffered serious burns to the thorax. The rescue services arrived on the scene and I was taken to the medical station'. Fortunately, this is not an account of real events but a scenario given to one of 20 volunteer 'victims' who took part in a large-scale safety exercise in the LHCb cavern. On 26 September, the CERN Fire Brigade organised a spectacular exercise in collaboration with the CERN Medical Service, the Fire and Rescue Service (SDIS) of the Department of t...

  19. 'Home Plate' Evidence for an Explosive Past

    Science.gov (United States)

    2006-01-01

    This view of layers around the edge of a low plateau called 'Home Plate' inside Mars' Gusev Crater includes a feature that may be what geologists call a 'bomb sag' and interpret as evidence of an explosive event, such as a volcanic eruption. The layers seen here are generally straight and parallel except in the lower right, where they dip around a greyish rock that is about 4 centimeters (about 1.5 inches) in diameter. When layered deposits are struck by a falling rock while the layers are still soft, this type of pattern can be created. The rock might have been lofted by a volcanic burst or as part of the material ejected by the crater-forming impact of a meteorite. The panoramic camera (Pancam) on NASA's Mars Exploration Rover Spirit acquired the exposures for this image on Spirit's 754th Martian day (Feb. 15, 2006). This view is an approximately true-color rendering mathematically generated from separate images taken through all of the left Pancam's 432-nanometer to 753-nanometer filters.

  20. Color camera pyrometry for high explosive detonations

    Science.gov (United States)

    Densmore, John; Biss, Matthew; Homan, Barrie; McNesby, Kevin

    2011-06-01

    Temperature measurements of high-explosive and combustion processes are difficult because of the speed and environment of the events. We have characterized and calibrated a digital high-speed color camera that may be used as an optical pyrometer to overcome these challenges. The camera provides both high temporal and spatial resolution. The color filter array of the sensor uses three color filters to measure the spectral distribution of the imaged light. A two-color ratio method is used to calculate a temperature using the color filter array raw image data and a gray-body assumption. If the raw image data is not available, temperatures may be calculated from processed images or movies depending on proper analysis of the digital color imaging pipeline. We analyze three transformations within the pipeline (demosaicing, white balance, and gamma-correction) to determine their effect on the calculated temperature. Using this technique with a Vision Research Phantom color camera, we have measured the temperature of exploded C-4 charges. The surface temperature of the resulting fireball rapidly increases after detonation and then decayed to a constant value of approximately 1980 K. Processed images indicates that the temperature remains constant until the light intensity decreased below the background value.

  1. Characteristics of acoustic wave from atmospheric nuclear explosions conducted at the USSR Test Sites

    Science.gov (United States)

    Sokolova, Inna

    2015-04-01

    Availability of the acoustic wave on the record of microbarograph is one of discriminate signs of atmospheric (surface layer of atmosphere) and contact explosions. Nowadays there is large number of air wave records from chemical explosions recorded by the IMS infrasound stations installed during recent decade. But there is small number of air wave records from nuclear explosions as air and contact nuclear explosions had been conducted since 1945 to 1962, before the Limited Test Ban Treaty was signed in 1963 (the treaty banning nuclear weapon tests in the atmosphere, in outer space and under water) by the Great Britain, USSR and USA. That time there was small number of installed microbarographs. First infrasound stations in the USSR appeared in 1954, and by the moment of the USSR collapse the network consisted of 25 infrasound stations, 3 of which were located on Kazakhstan territory - in Kurchatov (East Kazakhstan), in Borovoye Observatory (North Kazakhstan) and Talgar Observatory (Northern Tien Shan). The microbarograph of Talgar Observatory was installed in 1962 and recorded large number of air nuclear explosions conducted at Semipalatinsk Test Site and Novaya Zemlya Test Site. The epicentral distance to the STS was ~700 km, and to Novaya Zemlya Test Site ~3500 km. The historical analog records of the microbarograph were analyzed on the availability of the acoustic wave. The selected records were digitized, the database of acoustic signals from nuclear explosions was created. In addition, acoustic signals from atmospheric nuclear explosions conducted at the USSR Test Sites were recorded by analogue broadband seismic stations at wide range of epicentral distances, 300-3600 km. These signals coincide well by its form and spectral content with records of microbarographs and can be used for monitoring tasks and discrimination in places where infrasound observations are absent. Nuclear explosions which records contained acoustic wave were from 0.03 to 30 kt yield for

  2. Photoluminescent Detection of Dissolved Underwater Trace Explosives

    Directory of Open Access Journals (Sweden)

    Tye Langston

    2010-01-01

    Full Text Available A portable, rapid, and economical method for in situ trace explosive detection in aqueous solutions was demonstrated using photoluminescence. Using europium/thenoyltrifluoroacetone as the reagent, dissolved nitroglycerin was fluorescently tagged and detected in seawater solutions without sample preparation, drying, or preconcentration. The chemical method was developed in a laboratory setting and demonstrated in a flow-through configuration using lightweight, inexpensive, commercial components by directly injecting the reagents into a continually flowing seawater stream using a small amount of organic solvent (approximately 8% of the total solution. Europium's vulnerability to vibrational fluorescence quenching by water provided the mode of detection. Without nitroglycerin in the seawater solution, the reagent's fluorescence was quenched, but when dissolved nitroglycerin was present, it displaced the water molecules from the europium/thenoyltrifluoroacetone compound and restored fluorescence. This effort focused on developing a seawater sensor, but performance comparisons were made to freshwater. The method was found to perform better in freshwater and it was shown that certain seawater constituents (such as calcium have an adverse impact. However, the concentrations of these constituents are not expected to vary significantly from the natural seawater used herein.

  3. Could a nearby supernova explosion have caused a mass extinction?

    Science.gov (United States)

    Ellis, J; Schramm, D N

    1995-01-03

    We examine the possibility that a nearby supernova explosion could have caused one or more of the mass extinctions identified by paleontologists. We discuss the possible rate of such events in the light of the recent suggested identification of Geminga as a supernova remnant less than 100 parsec (pc) away and the discovery of a millisecond pulsar about 150 pc away and observations of SN 1987A. The fluxes of gamma-radiation and charged cosmic rays on the Earth are estimated, and their effects on the Earth's ozone layer are discussed. A supernova explosion of the order of 10 pc away could be expected as often as every few hundred million years and could destroy the ozone layer for hundreds of years, letting in potentially lethal solar ultraviolet radiation. In addition to effects on land ecology, this could entail mass destruction of plankton and reef communities, with disastrous consequences for marine life as well. A supernova extinction should be distinguishable from a meteorite impact such as the one that presumably killed the dinosaurs at the "KT boundary." The recent argument that the KT event was exceedingly large and thus quite rare supports the need for other catastrophic events.

  4. Could a nearby supernova explosion have caused a mass extinction?

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, J. [European Organization for Nuclear Research, Geneva (Switzerland); Schramm, D.N. [Univ. of Chicago, IL (United States)]|[Fermi National Accelerator Lab., Batavia, IL (United States)

    1995-01-03

    We examine the possibility that a nearby supernova explosion could have caused one or more of the mass extinctions identified by paleontologists. We discuss the possible rate of such events in the light of the recent suggested identification of Geminga as a supernova remnant less than 100 parsec (pc) away and the discovery of a millisecond pulsar about 150 pc away and observations of SN 1987A. The fluxes of {gamma}-radiation and charged cosmic rays on the Earth are estimated, and their effects on the Earth`s ozone layer are discussed. A supernova explosion of the order of 10 pc away could be expected as often as every few hundred million years and could destroy the ozone layer for hundreds of years, letting in potentially lethal solar ultraviolet radiation. In addition to effects on land ecology, this could entail mass destruction of plankton and reef communities, with disastrous consequences for marine life as well. A supernova extinction should be distinguishable from a meteorite impact such as the one that presumably killed the dinosaurs at the {open_quotes}KT boundary.{close_quotes} The recent argument that the KT event was exceedingly large and thus quite rare supports the need for other catastrophic events. 24 refs.

  5. Fossils, molecules and embryos: new perspectives on the Cambrian explosion

    Science.gov (United States)

    Valentine, J. W.; Jablonski, D.; Erwin, D. H.

    1999-01-01

    The Cambrian explosion is named for the geologically sudden appearance of numerous metazoan body plans (many of living phyla) between about 530 and 520 million years ago, only 1.7% of the duration of the fossil record of animals. Earlier indications of metazoans are found in the Neoproterozic; minute trails suggesting bilaterian activity date from about 600 million years ago. Larger and more elaborate fossil burrows appear near 543 million years ago, the beginning of the Cambrian Period. Evidence of metazoan activity in both trace and body fossils then increased during the 13 million years leading to the explosion. All living phyla may have originated by the end of the explosion. Molecular divergences among lineages leading to phyla record speciation events that have been earlier than the origins of the new body plans, which can arise many tens of millions of years after an initial branching. Various attempts to date those branchings by using molecular clocks have disagreed widely. While the timing of the evolution of the developmental systems of living metazoan body plans is still uncertain, the distribution of Hox and other developmental control genes among metazoans indicates that an extensive patterning system was in place prior to the Cambrian. However, it is likely that much genomic repatterning occurred during the Early Cambrian, involving both key control genes and regulators within their downstream cascades, as novel body plans evolved.

  6. Explosion Testing of a Polycarbonate Safe Haven Wall

    Science.gov (United States)

    Perry, Kyle A.; Meyr, Rex A.

    2016-12-01

    The MINER Act of 2006 was enacted by MSHA following the major mining accidents and required every underground coal mine to install refuge areas to help prevent future fatalities of trapped miners in the event of a disaster where the miners cannot escape. A polycarbonate safe haven wall for use in underground coal mines as component of a complete system was designed and modeled using finite element modeling in ANSYS Explicit Dynamics to withstand the MSHA required 15 psi (103.4 kPa) blast loading spanning 200 milliseconds. The successful design was constructed at a uniform height in both half-width scale and quarter-width scale in the University of Kentucky Explosives Research Team's (UKERT) explosives driven shock tube for verification of the models. The constructed polycarbonate walls were tested multiple times to determine the walls resistance to pressures generated by an explosion. The results for each test were analyzed and averaged to create one pressure versus time waveform which was then imported into ANSYS Explicit Dynamics and modeled to compare results to that which was measured during testing for model validation. This paper summarizes the results.

  7. Assessment of steam explosion impact on KNGR plant

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Moon Kyu; Park, Soo Yong; Park, Ik Kyu

    1999-03-01

    In present day light water reactors, if complete and prolonged failure of normal and emergency coolant flow occurs, fission product decay heat could cause melting of the reactor fuel. If the molten fuel mass accumulates it may relocate into reactor lower plenum and if the lower head fails it may eventually be brought into the reactor cavity. In such course of core melt relocation, the opportunity for fuel-coolant interactions (FCI) arises as the core melt relocates into water pool in reactor vessel as well as in reactor cavity and also, as a consequence of implementing accident management strategies involving water addition to a degraded or molten core. This report presents the methodologies and their results for assessment of steam explosion impact on KNGR plant integrity. Both in-vessel and ex-vessel phenomena are addressed. For in-vessel steam explosion, TRACER-II code is used for assessment of pressure load, while bounding calculations are applied for ex-vessel analysis. Analysis shows that the integrity of reactor pressure vessel lower head is preserved during the in-vessel event and the probability that the containment integrity is challenged is very low, even when ex-vessel steam explosion is allowed due to reactor vessel failure. (Author). 15 refs., 2 tabs., 4 figs.

  8. Computational Study of Scenarios Regarding Explosion Risk Mitigation

    Science.gov (United States)

    Vlasin, Nicolae-Ioan; Mihai Pasculescu, Vlad; Florea, Gheorghe-Daniel; Cornel Suvar, Marius

    2016-10-01

    Exploration in order to discover new deposits of natural gas, upgrading techniques to exploit these resources and new ways to convert the heat capacity of these gases into industrial usable energy is the research areas of great interest around the globe. But all activities involving the handling of natural gas (exploitation, transport, combustion) are subjected to the same type of risk: the risk to explosion. Experiments carried out physical scenarios to determine ways to reduce this risk can be extremely costly, requiring suitable premises, equipment and apparatus, manpower, time and, not least, presenting the risk of personnel injury. Taking in account the above mentioned, the present paper deals with the possibility of studying the scenarios of gas explosion type events in virtual domain, exemplifying by performing a computer simulation of a stoichiometric air - methane explosion (methane is the main component of natural gas). The advantages of computer-assisted imply are the possibility of using complex virtual geometries of any form as the area of deployment phenomenon, the use of the same geometry for an infinite number of settings of initial parameters as input, total elimination the risk of personnel injury, decrease the execution time etc. Although computer simulations are hardware resources consuming and require specialized personnel to use the CFD (Computational Fluid Dynamics) techniques, the costs and risks associated with these methods are greatly diminished, presenting, in the same time, a major benefit in terms of execution time.

  9. TWO-DIMENSIONAL SIMULATIONS OF EXPLOSIVE ERUPTIONS OF KICK-EM JENNY AND OTHER SUBMARINE VOLCANOS

    Directory of Open Access Journals (Sweden)

    Galen Gisler

    2006-01-01

    Full Text Available Kick-em Jenny, in the Eastern Caribbean, is a submerged volcanic cone that has erupted a dozen or more times since its discovery in 1939. The most likely hazard posed by this volcano is to shipping in the immediate vicinity (through volcanic missiles or loss-of-buoyancy, but it is of interest to estimate upper limits on tsunamis that might be produced by a catastrophic explosive eruption. To this end, we have performed two-dimensional simulations of such an event in a geometry resembling that of Kick-em Jenny with our SAGE adaptive mesh Eulerian multifluid compressible hydrocode. We use realistic equations of state for air, water, and basalt, and follow the event from the initial explosive eruption, through the generation of a transient water cavity and the propagation of waves away from the site. We find that even for extremely catastrophic explosive eruptions, tsunamis from Kick-em Jenny are unlikely to pose significant danger to nearby islands. For comparison, we have also performed simulations of explosive eruptions at the much larger shield volcano Vailulu'u in the Samoan chain, where the greater energy available can produce a more impressive wave. In general, however, we conclude that explosive eruptions do not couple well to water waves. The waves that are produced from such events are turbulent and highly dissipative, and don't propagate well. This is consistent with what we have found previously in simulations of asteroid-impact generated tsunamis. Non-explosive events, however, such as landslides or gas hydrate releases, do couple well to waves, and our simulations of tsunamis generated by sub- aerial and sub-aqueous landslides demonstrate this.

  10. Two-dimensional simulations of explosive eruptions of Kick-em Jenny and other submarine volcanos

    Energy Technology Data Exchange (ETDEWEB)

    Gisler, Galen R.; Weaver, R. P. (Robert P.); Mader, Charles L.; Gittings, M. L. (Michael L.)

    2004-01-01

    Kick-em Jenny, in the Eastern Caribbean, is a submerged volcanic cone that has erupted a dozen or more times since its discovery in 1939. The most likely hazard posed by this volcano is to shipping in the immediate vicinity (through volcanic missiles or loss-of-buoyancy), but it is of interest to estimate upper limits on tsunamis that might be produced by a catastrophic explosive eruption. To this end, we have performed two-dimensional simulations of such an event in a geometry resembling that of Kick-em Jenny with our SAGE adaptive mesh Eulerian multifluid compressible hydrocode. We use realistic equations of state for air, water, and basalt, and follow the event from the initial explosive eruption, through the generation of a transient water cavity and the propagation of waves away from the site. We find that even for extremely catastrophic explosive eruptions, tsunamis from Kick-em Jenny are unlikely to pose significant danger to nearby islands. For comparison, we have also performed simulations of explosive eruptions at the much larger shield volcano Vailuluu in the Samoan chain, where the greater energy available can produce a more impressive wave. In general, however, we conclude that explosive eruptions do not couple well to water waves. The waves that are produced from such events are turbulent and highly dissipative, and don't propagate well. This is consistent with what we have found previously in simulations of asteroid-impact generated tsunamis. Non-explosive events, however, such as landslides or gas hydrate releases, do couple well to waves, and our simulations of tsunamis generated by subaerial and sub-aqueous landslides demonstrate this.

  11. Fire and explosion hazards of oil shale

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    The US Bureau of Mines publication presents the results of investigations into the fire and explosion hazards of oil shale rocks and dust. Three areas have been examined: the explosibility and ignitability of oil shale dust clouds, the fire hazards of oil shale dust layers on hot surfaces, and the ignitability and extinguishment of oil shale rubble piles. 10 refs., 54 figs., 29 tabs.

  12. Sensitivity to friction for primary explosives

    Energy Technology Data Exchange (ETDEWEB)

    Matyas, Robert, E-mail: robert.matyas@upce.cz [Institute of Energetic Materials, Faculty of Chemical Technology, University of Pardubice, Pardubice 532 10 (Czech Republic); Selesovsky, Jakub; Musil, Tomas [Institute of Energetic Materials, Faculty of Chemical Technology, University of Pardubice, Pardubice 532 10 (Czech Republic)

    2012-04-30

    Highlights: Black-Right-Pointing-Pointer The friction sensitivity of 14 samples of primary explosives was determined. Black-Right-Pointing-Pointer The same apparatus (small scale BAM) and the same method (probit analysis) was used. Black-Right-Pointing-Pointer The crystal shapes and sizes were documented with microscopy. Black-Right-Pointing-Pointer Almost all samples are less sensitive than lead azide, which is commercially used. Black-Right-Pointing-Pointer The organic peroxides (TATP, DADP, HMTD) are not as sensitive as often reported. - Abstract: The sensitivity to friction for a selection of primary explosives has been studied using a small BAM friction apparatus. The probit analysis was used for the construction of a sensitivity curve for each primary explosive tested. Two groups of primary explosives were chosen for measurement (a) the most commonly used industrially produced primary explosives (e.g. lead azide, tetrazene, dinol, lead styphnate) and (b) the most produced improvised primary explosives (e.g. triacetone triperoxide, hexamethylenetriperoxide diamine, mercury fulminate, acetylides of heavy metals). A knowledge of friction sensitivity is very important for determining manipulation safety for primary explosives. All the primary explosives tested were carefully characterised (synthesis procedure, shape and size of crystals). The sensitivity curves obtained represent a unique set of data, which cannot be found anywhere else in the available literature.

  13. Explosive Joining for Nuclear-Reactor Repair

    Science.gov (United States)

    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.

  14. Forecasting volcanic explosions based on seismic quiescence

    Science.gov (United States)

    Roman, D.; La Femina, P.; Rodgers, M.; Geirsson, H.; Tenorio, V.

    2016-12-01

    Volcanic eruptions are generally forecast based on strong increases in monitoring parameters such as seismicity or gas emissions above a relatively low background level. Because of this, forecasting individual explosions during an ongoing eruption, or at persistently restless volcanoes, is difficult as seismicity, gas emissions, and other indicators of unrest are already in a heightened state. Therefore, identification of short-term precursors to individual explosions at volcanoes already in heightened states of unrest, and an understanding of explosion trigger mechanisms, is important for the reduction of volcanic risk worldwide. Seismic and visual observations at Telica Volcano, Nicaragua, demonstrate that a) episodes of seismic quiescence reliably preceded explosions during an eruption in May 2011 and b) the duration of precursory quiescence and the energy released in the ensuing explosion were strongly correlated. Precursory seismic quiescence is interpreted as the result of sealing of shallow gas pathways, leading to pressure accumulation and eventual catastrophic failure of the system, culminating in an explosion. Longer periods of sealing and pressurization lead to greater energy release in the ensuing explosion. Near-real-time observations of seismic quiescence at restless or erupting volcanoes can thus be useful for both timely eruption warnings and for forecasting the energy of impending explosions.

  15. Some analytical methods for explosives: Part 2

    Energy Technology Data Exchange (ETDEWEB)

    Selig, W.

    1965-12-08

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

  16. Detection and dispersal of explosives by ants

    Science.gov (United States)

    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.

  17. 76 FR 8923 - Explosive Siting Requirements

    Science.gov (United States)

    2011-02-16

    ... launch site in Title 14, Code of Federal Regulations (14 CFR) part 420. Part of the application for a... operational requirements of other regulatory regimes, they do not pose a risk of fire or explosion. Isolating... explosion due to the mixing of the two. In accordance with current DDESB and National Fire Protection...

  18. Characterization of mock high-explosive powder

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, C.R.; Dorsey, G.F.

    1979-03-01

    Analytical characterization and explosibility tests were made on a simulative high-explosive powder consisting of cyanuric acid, melamine, nitrocellulose, and tris-(..beta..-chloroethyl)-phosphate. Tests indicated that the powder presents no unusual safety or health hazards in isostatic-pressing and dry-machining operations.

  19. Explosion risks and consequences for tunnels

    NARCIS (Netherlands)

    Weerheijm, J.; Berg, A.C. van den

    2014-01-01

    Tunnel accidents with transports of dangerous goods may lead to explosions. Risk assessment for these accidents is complicated because of the low probability and the unknown, but disastrous effects expected. Especially the lack of knowledge on the strength of the explosion and the consequences for

  20. 33 CFR 401.67 - Explosive vessels.

    Science.gov (United States)

    2010-07-01

    ... 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. 49 CFR 173.54 - Forbidden explosives.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Forbidden explosives. 173.54 Section 173.54 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... SHIPMENTS AND PACKAGINGS Definitions, Classification and Packaging for Class 1 § 173.54 Forbidden explosives...

  2. The St Marys fragmentation grenade explosion.

    Science.gov (United States)

    Nocera, A

    1997-05-19

    The accidental explosion of a fragmentation grenade in a munitions factory at St Marys injured four workers, two critically. The prompt response by ambulances and physician-staffed helicopter emergency medical service prevented deaths, but the incident suggests lessons for the future handling of urban explosions.

  3. The ALMA View of the OMC1 Explosion in Orion

    OpenAIRE

    Bally, John; Ginsburg, Adam; Arce, Hector; Eisner, Josh; Youngblood, Allison; Zapata, Luis; Zinnecker, Hans

    2017-01-01

    Most massive stars form in dense clusters where gravitational interactions with other stars may be common. The two nearest forming massive stars, the BN object and Source I, located behind the Orion Nebula, were ejected with velocities of $\\sim$29 and $\\sim$13 km s$^{-1}$ about 500 years ago by such interactions. This event generated an explosion in the gas. New ALMA observations show in unprecedented detail, a roughly spherically symmetric distribution of over a hundred $^{12}$CO J=2$-$1 str...

  4. Hydrodynamics of Explosion Experiments and Models

    CERN Document Server

    Kedrinskii, Valery K

    2005-01-01

    Hydronamics of Explosion presents the research results for the problems of underwater explosions and contains a detailed analysis of the structure and the parameters of the wave fields generated by explosions of cord and spiral charges, a description of the formation mechanisms for a wide range of cumulative flows at underwater explosions near the free surface, and the relevant mathematical models. Shock-wave transformation in bubbly liquids, shock-wave amplification due to collision and focusing, and the formation of bubble detonation waves in reactive bubbly liquids are studied in detail. Particular emphasis is placed on the investigation of wave processes in cavitating liquids, which incorporates the concepts of the strength of real liquids containing natural microinhomogeneities, the relaxation of tensile stress, and the cavitation fracture of a liquid as the inversion of its two-phase state under impulsive (explosive) loading. The problems are classed among essentially nonlinear processes that occur unde...

  5. [Explosion injuries - prehospital care and management].

    Science.gov (United States)

    Holsträter, Thorsten; Holsträter, Susanne; Rein, Daniela; Helm, Matthias; Hossfeld, Björn

    2013-11-01

    Explosion injuries are not restricted to war-like military conflicts or terrorist attacks. The emergency physician may also encounter such injuries in the private or industrial fields, injuries caused by fireworks or gas explosions. In such cases the injury patterns are especially complex and may consist of blunt and penetrating injuries as well as thermal damage. Emergency medical personnel must be prepared to cope with explosion trauma not only in individual cases but also in major casualty incidents (MCI). This necessitates a sound knowledge about the mechanisms and processes of an explosion as well as the particular pathophysiological relationships of explosion injuries in order to be able to initiate the best possible, guideline-conform trauma therapy. © Georg Thieme Verlag Stuttgart · New York.

  6. Explosion interaction with water in a tube

    Science.gov (United States)

    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.

  7. Quantification of non-ideal explosion violence with a shock tube

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-01-01

    There is significant interest in quantifying the blast violence associated with various nonideal explosions. Such data is essential to evaluate the damage potential of both explosive cookoff and terrorist explosive scenarios. We present a technique designed to measure the source energy associated with a non-ideal, asymmetrical, and three-dimensional explosion. A tube is used to confine and focus energy from a blast event into a one-dimensional, quasi-planar shock front. During propagation along the length of the tube, the wave is allowed to shocksteepen into a more ideal form. Pressure transducers then measure the shock overpressure as a function of the distance from the source. One-dimensional blast scaling theory allows calculation of the source energy from this data. This small-scale test method addresses cost and noise concerns as well as boosting and symmetry issues associated with large-scale, three-dimensional, blast arena tests. Results from both ideal explosives and non-ideal explosives are discussed.

  8. Explosively produced megagauss fields and recent solid state applications

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, C.M.; Freeman, B.L.; Hults, W.L.; King, J.C.; Mueller, F.M.; Rickel, D.G.; Smith, J.L. [Los Alamos National Lab., NM (United States); Brooks, J.S.; Goettee, J.D. [Boston Univ., MA (United States). Dept. of Physics

    1993-12-31

    Large magnetic fields may be generated by compression of an initial magnetic flux generated over a large area at relatively low magnetic field into a region of smaller area. Following a discussion of flux compression principles, the authors discuss megagauss field systems in use at Los Alamos where chemical explosives are used to compress the flux. Their use in some solid state experiments will be discussed briefly, including a planned set of experiments on YBCO to be done jointly with a Russian team, whose aim is to determine the low temperature, critical magnetic field of YBCO.

  9. Introduction to Physics and Chemistry of Combustion Explosion, Flame, Detonation

    CERN Document Server

    Liberman, Michael A

    2008-01-01

    Most of the material covered in this book deals with the fundamentals of chemistry and physics of key processes and fundamental mechanisms for various combustion and combustion related phenomena in gaseous combustible mixture. It provides the reader with basic knowledge of burning processes and mechanisms of reaction wave propagation. The combustion of a gas mixture (flame, explosion, detonation) is necessarily accompanied by motion of the gas. The process of combustion is therefore not only a chemical phenomenon but also one of gas dynamics. The material selection focuses on the gas phase and

  10. Multichannel Discriminative Detection of Explosive Vapors with an Array of Nanofibrous Membranes Loaded with Quantum Dots

    Science.gov (United States)

    Wu, Zhaofeng; Duan, Haiming; Li, Zhijun; Guo, Jixi; Zhong, Furu; Cao, Yali; Jia, Dianzeng

    2017-01-01

    The multichannel fluorescent sensor array based on nanofibrous membranes loaded with ZnS quantum dots (QDs) was created and demonstrated for the discriminative detection of explosives. The synergistic effect of the high surface-to-volume ratio of QDs, the good permeability of nanofibrous membranes and the differential response introduced by surface ligands was played by constructing the sensing array using nanofibrous membranes loaded with ZnS QDs featuring several surface ligands. Interestingly, although the fluorescence quenching of the nanofibrous membranes is not linearly related to the exposure time, the fingerprint of each explosive at different times is very similar in shape, and the fingerprints of the three explosives show different shapes. Three saturated vapors of nitroaromatic explosives could be reliably detected and discriminated by the array at room temperature. This work is the first step toward devising a monitoring system for explosives in the field of public security and defense. It could, for example, be coupled with the technology of image recognition and large data analysis for a rapid diagnostic test of explosives. This work further highlights the power of differential, multichannel arrays for the rapid and discriminative detection of a wide range of chemicals. PMID:29156627

  11. Multichannel Discriminative Detection of Explosive Vapors with an Array of Nanofibrous Membranes Loaded with Quantum Dots

    Directory of Open Access Journals (Sweden)

    Zhaofeng Wu

    2017-11-01

    Full Text Available The multichannel fluorescent sensor array based on nanofibrous membranes loaded with ZnS quantum dots (QDs was created and demonstrated for the discriminative detection of explosives. The synergistic effect of the high surface-to-volume ratio of QDs, the good permeability of nanofibrous membranes and the differential response introduced by surface ligands was played by constructing the sensing array using nanofibrous membranes loaded with ZnS QDs featuring several surface ligands. Interestingly, although the fluorescence quenching of the nanofibrous membranes is not linearly related to the exposure time, the fingerprint of each explosive at different times is very similar in shape, and the fingerprints of the three explosives show different shapes. Three saturated vapors of nitroaromatic explosives could be reliably detected and discriminated by the array at room temperature. This work is the first step toward devising a monitoring system for explosives in the field of public security and defense. It could, for example, be coupled with the technology of image recognition and large data analysis for a rapid diagnostic test of explosives. This work further highlights the power of differential, multichannel arrays for the rapid and discriminative detection of a wide range of chemicals.

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

    Energy Technology Data Exchange (ETDEWEB)

    Villa-Aleman, E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-10-08

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

  13. Explosion probability of unexploded ordnance: expert beliefs.

    Science.gov (United States)

    MacDonald, Jacqueline Anne; Small, Mitchell J; Morgan, M G

    2008-08-01

    This article reports on a study to quantify expert beliefs about the explosion probability of unexploded ordnance (UXO). Some 1,976 sites at closed military bases in the United States are contaminated with UXO and are slated for cleanup, at an estimated cost of $15-140 billion. Because no available technology can guarantee 100% removal of UXO, information about explosion probability is needed to assess the residual risks of civilian reuse of closed military bases and to make decisions about how much to invest in cleanup. This study elicited probability distributions for the chance of UXO explosion from 25 experts in explosive ordnance disposal, all of whom have had field experience in UXO identification and deactivation. The study considered six different scenarios: three different types of UXO handled in two different ways (one involving children and the other involving construction workers). We also asked the experts to rank by sensitivity to explosion 20 different kinds of UXO found at a case study site at Fort Ord, California. We found that the experts do not agree about the probability of UXO explosion, with significant differences among experts in their mean estimates of explosion probabilities and in the amount of uncertainty that they express in their estimates. In three of the six scenarios, the divergence was so great that the average of all the expert probability distributions was statistically indistinguishable from a uniform (0, 1) distribution-suggesting that the sum of expert opinion provides no information at all about the explosion risk. The experts' opinions on the relative sensitivity to explosion of the 20 UXO items also diverged. The average correlation between rankings of any pair of experts was 0.41, which, statistically, is barely significant (p= 0.049) at the 95% confidence level. Thus, one expert's rankings provide little predictive information about another's rankings. The lack of consensus among experts suggests that empirical studies

  14. Noble Gas Migration Experiment to Support the Detection of Underground Nuclear Explosions

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, Khris B.; Kirkham, Randy R.; Woods, Vincent T.; Haas, Derek A.; Hayes, James C.; Bowyer, Ted W.; Mendoza, Donaldo P.; Lowrey, Justin D.; Lukins, Craig D.; Suarez, Reynold; Humble, Paul H.; Ellefson, Mark D.; Ripplinger, Mike D.; Zhong, Lirong; Mitroshkov, Alexandre V.; Aalseth, Craig E.; Prinke, Amanda M.; Mace, Emily K.; McIntyre, Justin I.; Stewart, Timothy L.; Mackley, Rob D.; Milbrath, Brian D.; Emer, Dudley; Biegalski, S.

    2016-03-01

    A Noble Gas Migration Experiment (NGME) funded by the National Center for Nuclear Security and conducted at the Nevada National Security Site (NNSS) in collaboration with Lawrence Livermore national Laboratory and National Security Technology provided critical on-site inspection (OSI) information related to the detection of an underground nuclear explosion (UNE) event using noble gas signatures.

  15. Detonating Failed Deflagration Model of Thermonuclear Supernovae. I. Explosion Dynamics

    Science.gov (United States)

    Plewa, Tomasz

    2007-03-01

    We present a detonating failed deflagration model of Type Ia supernovae. In this model, the thermonuclear explosion of a massive white dwarf follows an off-center deflagration. We conduct a survey of asymmetric ignition configurations initiated at various distances from the stellar center. In all cases studied, we find that only a small amount of stellar fuel is consumed during deflagration phase, no explosion is obtained, and the released energy is mostly wasted on expanding the progenitor. Products of the failed deflagration quickly reach the stellar surface, polluting and strongly disturbing it. These disturbances eventually evolve into small and isolated shock-dominated regions that are rich in fuel. We consider these regions as seeds capable of forming self-sustained detonations that, ultimately, result in the thermonuclear supernova explosion. Preliminary nucleosynthesis results indicate that the model supernova ejecta are typically composed of about 0.1-0.25 Msolar of silicon group elements and 0.9-1.2 Msolar of iron group elements and are essentially carbon-free. The ejecta have a composite morphology, are chemically stratified, and display a modest amount of intrinsic asymmetry. The innermost layers are slightly egg shaped with the axis ratio ~1.2-1.3 and dominated by the products of silicon burning. This central region is surrounded by a shell of silicon group elements. The outermost layers of ejecta are highly inhomogeneous and contain products of incomplete oxygen burning with only small admixture of unburned stellar material. The explosion energies are ~(1.3-1.5)×1051 ergs.

  16. Surface Signatures of an Underground Explosion as Captured by Photogrammetry

    Science.gov (United States)

    Schultz-Fellenz, E. S.; Sussman, A. J.; Swanson, E.; Coppersmith, R.; Cooley, J.; Rougier, E.; Larmat, C. S.; Norskog, K.

    2016-12-01

    This study employed high-resolution photogrammetric modeling to quantify cm-scale surface topographic changes resulting from a 5000kg underground chemical explosion. The test occurred in April 2016 at a depth of 76m within a quartz monzonite intrusion in southern Nevada. The field area was a 210m x 150m polygon broadly centered on the explosion's emplacement hole. A grid of ground control points (GCPs) installed in the field area established control within the collection boundaries and ensured high-resolution digital model parameterization. Using RTK GPS techniques, GCP targets were surveyed in the days before and then again immediately after the underground explosion. A quadcopter UAS with a 12MP camera payload captured overlapping imagery at two flight altitudes (10m and 30m AGL) along automated flight courses for consistency and repeatability. The overlapping imagery was used to generate two digital elevation models, pre-shot and post-shot, for each of the flight altitudes. Spatial analyses of the DEMs and orthoimagery show uplift on the order of 1 to 18cm in the immediate area near ground zero. Other features such as alluvial fracturing appear in the photogrammetric and topographic datasets. Portions of the nearby granite outcrop experienced rock fall and rock rotation. The study detected erosional and depositional features on the test bed and adjacent to it. In addition to vertical change, pre-shot and post-shot surveys of the GCPs suggest evidence for lateral motion on the test bed surface, with movement away from surface ground zero on the order of 1 to 3cm. Results demonstrate that UAS photogrammetry method provides an efficient, high-fidelity, non-invasive method to quantify surface deformation. The photogrammetry data allow quantification of permanent surface deformation and of the spatial extent of damage. These constraints are necessary to develop hydrodynamic and seismic models of explosions that can be verified against recorded seismic data.

  17. Significant impacts of heterogeneous reactions on the chemical composition and mixing state of dust particles: A case study during dust events over northern China

    Science.gov (United States)

    Wang, Zhe; Pan, Xiaole; Uno, Itsushi; Li, Jie; Wang, Zifa; Chen, Xueshun; Fu, Pingqing; Yang, Ting; Kobayashi, Hiroshi; Shimizu, Atsushi; Sugimoto, Nobuo; Yamamoto, Shigekazu

    2017-06-01

    The impact of heterogeneous reactions on the chemical components and mixing state of dust particles are investigated by observations and an air quality model over northern China between March 27, 2015 and April 2, 2015. Synergetic observations were conducted using a polarization optical particle counter (POPC), a depolarized two-wavelength Lidar and filter samples in Beijing. During this period, dust plume passed through Beijing on March 28, and flew back on March 29 because of synoptic weather changes. Mineral dust mixed with anthropogenic pollutants was simulated using the Nested Air Quality Prediction Modeling System (NAQPMS) to examine the role of heterogeneous processes on the dust. A comparison of observations shows that the NAQPMS successfully reproduces the time series of the vertical profile, particulate matter concentration, and chemical components of fine mode (diameter ≤ 2.5 μm) and coarse mode (2.5 μm < diameter ≤ 10 μm) particles. After considering the heterogeneous reactions, the simulated nitrate, ammonium, and sulfate are in better agreement with the observed values during this period. The modeling results with observations show that heterogeneous reactions are the major mechanisms producing nitrate reaching 19 μg/m3, and sulfate reaching 7 μg/m3, on coarse mode dust particles, which were almost 100% of the coarse mode nitrate and sulfate. The heterogeneous reactions are also important for fine mode secondary aerosols, for producing 17% of nitrate and 11% of sulfate on fine mode dust particles, with maximum mass concentrations of 6 μg/m3 and 4 μg/m3. In contrast, due to uptake of acid gases (e.g. HNO3 and SO2) by dust particles, the fine mode anthropogenic ammonium nitrate and ammonium sulfate decreased. As a result, the total fine mode nitrate decreased with a maximum of 14 μg/m3, while the total fine mode sulfate increased with a maximum of 2 μg/m3. Because of heterogeneous reactions, 15% of fine mode secondary inorganic aerosols and

  18. Hydrocarbon Biomarker Stratigraphy of C-Isotopic Excursions Marking Chemical Changes in the Ocean with Contemporanious Biotic Extinction-Radiation Events

    Science.gov (United States)

    Summons, Roger E.

    2004-01-01

    One paper recording progress in this topic has been accepted for publication. We report a method for the rigorous identification of biomarkers (crocetane and PMI) that may be specific for methanotrophic and methanogenic archaea and, perhaps, the process of anaerobic oxidation of methane. If catastrophic methane efflux from sub-sea methane hydrate is responsible for extinction events, as has been hypothesized by many workers, then we might expect to find biomarkers for methane oxidation in sediments marking some extinction boundaries. Unfortunately, identifying crocetane and PMI with certainty is not a trivial exercise and these biomarkers appear to have been mis-identified in a recent publication by workers from Curtin University. Barber et al. (2001) identified crocetane and PMI in sediments deposited in the basal Triassic of the Perth Basin, Australia. However, Barber et al. (2001) also found crocetane and PMI in many other sediments and oils in a way that was inconsistent with our knowledge of these systems.

  19. Onset of the Magnetic Explosion in Solar Polar Coronal X-Ray Jets

    Science.gov (United States)

    Moore, Ronald L.; Sterling, Alphonse C.; Panesar, Navdeep

    2017-08-01

    We examine the onset of the driving magnetic explosion in 15 random polar coronal X-ray jets. Each eruption is observed in a coronal X-ray movie from Hinode and in a coronal EUV movie from Solar Dynamics Observatory. Contrary to the Sterling et al (2015, Nature, 523, 437) scenario for minifilament eruptions that drive polar coronal jets, these observations indicate: (1) in most polar coronal jets (a) the runaway internal tether-cutting reconnection under the erupting minifilament flux rope starts after the spire-producing breakout reconnection starts, not before it, and (b) aleady at eruption onset, there is a current sheet between the explosive closed magnetic field and ambient open field; and (2) the minifilament-eruption magnetic explosion often starts with the breakout reconnection of the outside of the magnetic arcade that carries the minifilament in its core. On the other hand, the diversity of the observed sequences of occurrence of events in the jet eruptions gives further credence to the Sterlling et al (2015, Nature, 523, 437) idea that the magnetic explosions that make a polar X-ray jet work the same way as the much larger magnetic explosions that make and flare and CME. We point out that this idea, and recent observations indicating that magnetic flux cancelation is the fundamental process that builds the field in and around pre-jet minifilaments and triggers the jet-driving magnetic explosion, together imply that usually flux cancelation inside the arcade that explodes in a flare/CME eruption is the fundamental process that builds the explosive field and triggers the explosion.This work was funded by the Heliophysics Division of NASA's Science Mission Directorate through its Living With a Star Targeted Research and Technology Program, its Heliophsyics Guest Investigators Program, and the Hinode Project.

  20. Determining VCE damage zones using the GAME correlations and explosion regions

    NARCIS (Netherlands)

    Boot, H.; Voort, M.M. van der

    2013-01-01

    Predicting potential consequences of Vapor Cloud Explosions (VCEs) has always been an important issue in safety assessments, because of the devastating damage that this phenomenon can create on (petro chemical) production sites. Although the TNO Multi-Energy method has been recognized as one of the

  1. Canard explosion of limit cycles in templator models of self-replication mechanisms

    DEFF Research Database (Denmark)

    Brøns, Morten

    2011-01-01

    Templators are differential equation models for self-replicating chemical systems. Beutel and Peacock-López [J. Chem. Phys. 126, 125104 (2007)]10.1063/1.2716396 have numerically analyzed a model for a cross-catalytic self-replicating system and found two cases of canard explosion, that is, a sub...

  2. Application of neutron generators for high explosives, toxic agents and fissile material detection.

    Science.gov (United States)

    Aleksandrov, V D; Bogolubov, E P; Bochkarev, O V; Korytko, L A; Nazarov, V I; Polkanov, Yu G; Ryzhkov, V I; Khasaev, T O

    2005-01-01

    The portable pulsed neutron generators developed and designed by VNIIA are presented. The neutron methods are good tools for non-destructive assay of dangerous materials. The samples of various systems for the detection of high explosives in luggage, identification of toxic agents in chemical munitions, and also for the prevention of illicit trafficking of fissile elements in passengers' luggage are discussed.

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

    Science.gov (United States)

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

    2017-08-01

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

  4. Numerical modelling of the effect of using multi-explosives on the explosive forming of steel cones

    OpenAIRE

    De Vuyst, T; Kong, K.; Djordjevic, N.; Vignjevic, R.; Campbell, JC; Hughes, K

    2016-01-01

    Modelling and analysis of underwater explosive forming process by using FEM and SPH formulation is presented in this work. The explosive forming of a steel cone is studied. The model setup includes a low carbon steel plate, plate holder, forming die as well as water and C4 explosive. The effect of multiple explosives on rate of targets deformation has been studied. Four different multi-explosives models have been developed and compared to the single explosive model. The formability of the ste...

  5. Facies distribution of ejecta in analog tephra rings from experiments with single and multiple subsurface explosions

    Science.gov (United States)

    Graettinger, A. H.; Valentine, G. A.; Sonder, I.; Ross, P.-S.; White, J. D. L.

    2015-08-01

    The volume, grain size, and depositional facies of material deposited outside an explosion crater, ejecta, are sensitive to the depth of the explosion, the explosion energy, and the presence or absence of a crater before the explosion. We detonate buried chemical explosives as an analog for discrete volcanic explosions in experiments to identify unique characteristics of proximal, medial, and distal ejecta facies and their distribution from a range of scaled depths in undisturbed and cratered ground. Ejecta are here discussed in terms of three facies: (1) proximal ejecta, which form a constructional landform around a crater; (2) medial ejecta, which form a continuous sheet deposit that thins much more gradually with distance; and (3) distal ejecta that are deposited as isolated clasts. The extent of proximal ejecta away from the crater, relative to crater size, is not sensitive to scaled depth, but the volume proportion of proximal ejecta to the total ejecta deposit is sensitive to the presence of a crater and scaled depth. Medial ejecta distribution and volume contributions are both sensitive to the presence of a crater and to scaled depth. Distal ejecta distance is dependent on scaled depth and the presence of a crater, while the volume proportion of distal ejecta is less sensitive to scaled depth or presence of a crater. Experimental facies and deposit structures inferred from observations of jet dynamics are used to suggest facies associations anticipated from eruptions dominated by explosions of different scaled depth configurations. We emphasize that significant differences in tephra ring deposits can result from the effects of scaled depth and preexisting craters on ejecta dynamics, and are not necessarily related to fundamental differences in explosion mechanisms or degree of magma fragmentation.

  6. Explosive Chemical Signature-Based Detection of IEDs

    National Research Council Canada - National Science Library

    Fisher, Mark

    2004-01-01

    ...; Modify and adapt the Fido sensor device to operation on a small robot; Integrate the Fido and high-volume sampling functions into a small footprint commensurate with operation of a small robot...

  7. Stellar survivor from explosion in 1572 AD

    Science.gov (United States)

    2004-10-01

    burned-out 'white dwarf' star. The normal star spills material onto the dwarf, eventually triggering an explosion. The results of this research, led by Pilar Ruiz-Lapuente of the University of Barcelona, Spain, are published in the 28 October issue of the British science journal Nature. "There was no previous evidence pointing to any specific kind of companion star out of the many that had been proposed. Here we have identified a clear path: the feeding star is similar to our sun, but slightly older," said Ruiz-Lapuente. "The high speed of the star called our attention to it," she added. Type Ia supernovae are used to measure the history of the expansion rate of the Universe and so are fundamental in helping astronomers understand the behaviour of 'dark energy', an unknown force that is accelerating the expansion of the Universe. Finding evidence to confirm the theory as to how Type Ia supernovae explode is critical to assuring astronomers that the objects can be better understood as reliable calibrators of the expansion of space. Although today's astronomers are looking at this event 432 years too late, they were still able to see a star rushing away from the location of the explosion (which is now enveloped in a vast bubble of hot gas called 'Tycho's Supernova Remnant'). The runaway star and its surroundings have been studied with a variety of telescopes for the past seven years. The NASA/ESA Hubble Space Telescope played a key role in the process by measuring the star's motion against the sky background precisely. The star is breaking the speed limit for that particular region of the Milky Way Galaxy by moving three times faster than the surrounding stars. When the system was disrupted by the white dwarf's explosion, the companion star went hurtling off into space, like a stone thrown by a sling, retaining the velocity of its orbital motion. However there are alternative explanations for this motion. It could be falling into the region from the galactic halo that

  8. 46 CFR 194.05-3 - Chemical stores.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Chemical stores. 194.05-3 Section 194.05-3 Shipping..., AND CONTROL OF EXPLOSIVES AND OTHER HAZARDOUS MATERIALS Stowage and Marking § 194.05-3 Chemical stores. (a) Chemical stores are those chemicals which possess one or more of the following properties and...

  9. Event Modeling

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    2001-01-01

    are dynamic and we present a modeling approach that can be used to model such dynamics. We characterize events as both information objects and change agents (Bækgaard 1997). When viewed as information objects events are phenomena that can be observed and described. For example, borrow events in a library can......The purpose of this chapter is to discuss conceptual event modeling within a context of information modeling. Traditionally, information modeling has been concerned with the modeling of a universe of discourse in terms of information structures. However, most interesting universes of discourse...... be characterized by their occurrence times and the participating books and borrowers. When we characterize events as information objects we focus on concepts like information structures. When viewed as change agents events are phenomena that trigger change. For example, when borrow event occurs books are moved...

  10. Chemical composition based aerosol optical properties according to size distribution and mixture types during smog and Asian dust events in Seoul, Korea

    Science.gov (United States)

    Jung, Chang Hoon; Lee, Ji Yi; Um, Junshik; Lee, Seung Soo; Kim, Yong Pyo

    2017-09-01

    This study investigated the optical properties of aerosols involved in different meteorological events, including smog and Asian dust days. Carbonaceous components and inorganic species were measured in Seoul, Korea between 25 and 31 March 2012. Based on the measurements, the optical properties of aerosols were calculated by considering composition, size distribution, and mixing state of aerosols. To represent polydisperse size distributions of aerosols, a lognormal size distribution with a wide range of geometric mean diameters and geometric standard deviations was used. For the optical property calculations, the Mie theory was used to compute single-scattering properties of aerosol particles with varying size and composition. Analysis of the sampled data showed that the water-soluble components of organic matter increased on smog days, whereas crustal elements increased on dust days. The water content significantly influenced the optical properties of aerosols during the smog days as a result of high relative humidity and an increase in the water-soluble component. The absorption coefficients depended on the aerosol mixture type and the aerosol size distributions. Therefore, to improve our knowledge on radiative impacts of aerosols, especially the regional impacts of aerosols in East Asia, accurate measurements of aerosols, such as size distribution, composition, and mixture type, under different meteorological conditions are required.

  11. Numerical modeling of the 1840s major eruption of η Carinae as an explosion

    Science.gov (United States)

    González, Ricardo F.

    2018-01-01

    In this paper, new two-dimensional hydrodynamical simulations of η Car's nebulae are performed. In the 1840s, the massive star η Car suffered a major eruption that resulted in the formation of a bipolar structure, which is commonly known as the large Homunculus. During this event, η Car expelled into the circumstellar material a total mass of 10 M⊙ and released a total energy of Ek 1050 erg over a very short time (≤5 yr). These kinds of explosive events are frequently called supernova impostors due to their resemblance to a type II supernova, but the stars survive the explosion. In the case of η Car, a brief explosion scenario provides a potential explanation for the behavior of the historical light curve of η Car a few years ( 10 yr) after the nineteenth century outburst. Here, such an alternative scenario of an explosion is assumed (instead of a super-Eddington wind) in order to investigate whether an explosive event is also able to explain the shape and kinematics of the large Homunculus. I show that the numerical simulations presented here indeed resemble some of the observed features of the nebula, such as the present-day double-shell structure of the Homunculus, with a thin outer dense shell and a thicker inner layer, as well as thermal instabilities (Rayleigh-Taylor and Kelvin-Helmholtz) along the dense shell that may lead to the current mottled appearance of the large Homunculus. Nonetheless, the explosion model for the 1840s major eruption of η Car is not able to account for the estimated age of the large Homunculus.

  12. Laser-Induced Explosion of Nitrated Carbon Nanotubes: Nonadiabatic and Reactive Molecular Dynamics Simulations.

    Science.gov (United States)

    Chaban, Vitaly V; Pal, Sougata; Prezhdo, Oleg V

    2016-12-14

    Laser-initiated decomposition of carbon nanotubes (CNTs) can lead to medical, military, and other applications. In medicine, CNTs give rise to efficient remedies against diseases and malignant cells, since they encapsulate drug molecules, can be delivered inside living organisms, and absorb light that penetrates through biological tissues. As explosives, pyrotechnics, and propellants, CNTs can be activated remotely by a visible or infrared laser, avoiding the need for a detonating cord. The reported non-equilibrium investigation demonstrates the possibility of photoinduced polynitro-CNT explosion and provides a detailed chemical mechanism of the decomposition process, explicitly in the time domain. Nonadiabatic molecular dynamics (MD) performed with real-time time-dependent tight-binding density functional theory demonstrates that the photogenerated exciton deposits its energy into a broad range of phonon modes within less than a picosecond, resulting in a rapid polynitro-CNT heating. Following the heating, reactive MD demonstrates an explosion, during which the local temperature of polynitro-CNTs and its fragments rises as high as 4000 K. Photoexcitation of nitro groups by a high-energy laser is not required; the energy can be delivered to polynitro-CNTs using near-infrared light within the biological window. Furthermore, the explosion is possible both with and without an external oxygen source. Anaerobic explosion could be particularly beneficial in confined biological and nanoscale environments. The products of the polynitro-CNT decomposition are nontoxic: carbon dioxide and molecular nitrogen. The in silico demonstration of the laser-induced polynitro-CNT explosion, its chemical mechanism, and the time scales of physical and chemical transformations can be tested experimentally using time-resolved laser techniques.

  13. Metal explosion chambers: designing, manufacturing, application

    Science.gov (United States)

    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.

  14. Wave dynamics of electric explosion in solids

    Science.gov (United States)

    Burkin, V. V.; Kuznetsova, N. S.; Lopatin, V. V.

    2009-05-01

    A mathematical model of an electric explosion is developed that consistently describes the expansion of the explosion channel with regard to the parameters of the discharge circuit of a high-voltage pulse generator, radiation, and propagation of stress waves in a solid. The dynamics of conversion of the stored energy to a wave and the formation of mechanical stresses due to electric explosion in a solid immersed in a liquid are considered. In the context of electro-discharge destruction of hard materials, the resulting stress field and the relationship between the discharge circuit parameters and characteristics of the wave are analyzed and the most efficient discharge modes are determined.

  15. The mathematical modeling of supernova explosion

    Science.gov (United States)

    Denisov, A. A.; Koldoba, A. V.; Poveshchenko, Iu. A.; Popov, Iu. P.; Chechetkin, V. M.

    An essentially two-dimensional model of supernova explosion is developed, with emphasis on the role of rotation in the thermonuclear explosion process. Attention is given to a star with a carbon-oxygen core, which is transformed into a nickel core as a result of nuclear reaction. In this case, the development of thermal instability leads to the generation of a detonation wave propagating to the periphery of the star. Rapid rotation is found to produce a strong asymmetry of the hydrodynamic processs of the explosion.

  16. Water waves generated by underwater explosion

    CERN Document Server

    Mehaute, Bernard Le

    1996-01-01

    This is the first book on explosion-generated water waves. It presents the theoretical foundations and experimental results of the generation and propagation of impulsively generated waves resulting from underwater explosions. Many of the theories and concepts presented herein are applicable to other types of water waves, in particular, tsunamis and waves generated by the fall of a meteorite. Linear and nonlinear theories, as well as experimental calibrations, are presented for cases of deep and shallow water explosions. Propagation of transient waves on dissipative, nonuniform bathymetries to

  17. Explosive Detection and Identification by PGNAA

    Energy Technology Data Exchange (ETDEWEB)

    E.H. Seabury; A.J. Caffrey

    2004-11-01

    The goal of this project was to determine the feasibility of using field-portable prompt gamma-ray neutron activation analysis (PGNAA) to detect and identify explosives in improvised nuclear devices (INDs). The studies were carried out using the Monte Carlo N-Particle (MCNP) code developed at Los Alamos National Laboratory. The model results were tested experimentally using explosive simulants and the PINS PGNAA system developed at Idaho National Engineering and Environmental Laboratory (INEEL). The results of the MCNP calculations and PINS measurements are presented in this report. The calculations and measurements were in good agreement and indicate that most explosives are readily distinguishable from one another.

  18. Effective responder communication improves efficiency and psychological outcomes in a mass decontamination field experiment: implications for public behaviour in the event of a chemical incident.

    Science.gov (United States)

    Carter, Holly; Drury, John; Amlôt, Richard; Rubin, G James; Williams, Richard

    2014-01-01

    The risk of incidents involving mass decontamination in response to a chemical, biological, radiological, or nuclear release has increased in recent years, due to technological advances, and the willingness of terrorists to use unconventional weapons. Planning for such incidents has focused on the technical issues involved, rather than on psychosocial concerns. This paper presents a novel experimental study, examining the effect of three different responder communication strategies on public experiences and behaviour during a mass decontamination field experiment. Specifically, the research examined the impact of social identity processes on the relationship between effective responder communication, and relevant outcome variables (e.g. public compliance, public anxiety, and co-operative public behaviour). All participants (n = 111) were asked to visualise that they had been involved in an incident involving mass decontamination, before undergoing the decontamination process, and receiving one of three different communication strategies: 1) 'Theory-based communication': Health-focused explanations about decontamination, and sufficient practical information; 2) 'Standard practice communication': No health-focused explanations about decontamination, sufficient practical information; 3) 'Brief communication': No health-focused explanations about decontamination, insufficient practical information. Four types of data were collected: timings of the decontamination process; observational data; and quantitative and qualitative self-report data. The communication strategy which resulted in the most efficient progression of participants through the decontamination process, as well as the fewest observations of non-compliance and confusion, was that which included both health-focused explanations about decontamination and sufficient practical information. Further, this strategy resulted in increased perceptions of responder legitimacy and increased identification with

  19. Effective responder communication improves efficiency and psychological outcomes in a mass decontamination field experiment: implications for public behaviour in the event of a chemical incident.

    Directory of Open Access Journals (Sweden)

    Holly Carter

    Full Text Available The risk of incidents involving mass decontamination in response to a chemical, biological, radiological, or nuclear release has increased in recent years, due to technological advances, and the willingness of terrorists to use unconventional weapons. Planning for such incidents has focused on the technical issues involved, rather than on psychosocial concerns. This paper presents a novel experimental study, examining the effect of three different responder communication strategies on public experiences and behaviour during a mass decontamination field experiment. Specifically, the research examined the impact of social identity processes on the relationship between effective responder communication, and relevant outcome variables (e.g. public compliance, public anxiety, and co-operative public behaviour. All participants (n = 111 were asked to visualise that they had been involved in an incident involving mass decontamination, before undergoing the decontamination process, and receiving one of three different communication strategies: 1 'Theory-based communication': Health-focused explanations about decontamination, and sufficient practical information; 2 'Standard practice communication': No health-focused explanations about decontamination, sufficient practical information; 3 'Brief communication': No health-focused explanations about decontamination, insufficient practical information. Four types of data were collected: timings of the decontamination process; observational data; and quantitative and qualitative self-report data. The communication strategy which resulted in the most efficient progression of participants through the decontamination process, as well as the fewest observations of non-compliance and confusion, was that which included both health-focused explanations about decontamination and sufficient practical information. Further, this strategy resulted in increased perceptions of responder legitimacy and increased

  20. Changes in toxicity and Ah receptor agonist activity of suspended particulate matter during flood events at the rivers Neckar and Rhine - a mass balance approach using in vitro methods and chemical analysis.

    Science.gov (United States)

    Wölz, Jan; Engwall, Magnus; Maletz, Sibylle; Olsman Takner, Helena; van Bavel, Bert; Kammann, Ulrike; Klempt, Martin; Weber, Roland; Braunbeck, Thomas; Hollert, Henner

    2008-10-01

    carbon fractions was determined in the EROD assay and expressed as biological toxicity equivalency concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (bio-TEQs). The calculation of chemical equivalency concentrations (chem-TEQs) and comparison to bio-TEQ values allowed the determination of the contribution of the analyzed persistent compounds to the total biological effects measured. Soluble compounds in native and extracted water samples resulted in no or minor activity in the toxicity tests, respectively. Filter residues of native water caused increased AhR-mediated activity at the peak of the flood. Activities of SPM of the river Neckar correlated well with the flow rate indicating a flood-dependent increase of toxicity culminating at the peak of flow. River Rhine SPM showed a decrease of activity regarding an SPM sample of the flood event compared to a long-term sample. Excellent correlations with AhR agonistic activity were determined for DR-CALUX and EROD assay, while the GPC.2D assay did not correlate with both other biotests. The activity of persistent dioxin-like acting compounds in multilayer and carbon fractionated PCDD/F and PCB fractions was low if compared to corresponding crude extracts. The congener pattern of PCDD/F revealed that the contaminations mainly originated from products and productions of the chlorine and organochlorine industries. Native and extracted water samples could be shown to contain little or no cytotoxic or AhR agonistic compounds. In contrast, particle-bound compounds were shown to be the relevant effect-causing fraction, as indicated by the activities of filter residues of native water and SPM. Compounds other than fractionated persistent PCBs and PCDD/Fs were more relevant to explain AhR-mediated activities of crude flood SPM at both rivers assessed. Biologically detected activities could at least in part be traced back to chemically analyzed and quantified compounds. The calculation of the portion of persistent PCBs and PCDD

  1. The steam explosion potential for an unseated SRS reactor septifoil

    Energy Technology Data Exchange (ETDEWEB)

    Allison, D.K.; Hyder, M.L.; Yau, W.W.F. [Westinghouse Savannah River Co., Aiken, SC (United States); Smith, D.C. [Science Applications International Corp., Albuquerque, NM (United States)

    1992-09-01

    Control rods in the Savannah River Site`s K Reactor are contained within housings composed of seven channels (``septifoils``). Each septifoil is suspended from the top of the reactor and is normally seated on an upflow pin that channels coolant to the septifoil. Forced flow to the septifoil would be eliminated in the unlikely event of a septifoil unseated upon installation, i.e., if the septifoil is not aligned with its upflow pin. If this event were not detected, control rod melting and the interaction of molten metal with water might occur. This paper describes a methodology used to address the issue of steam explosions that might arise by this mechanism. The probability of occurrence of a damaging steam explosion given an unseated septifoil was found to be extremely low. The primary reasons are: (1) the high probability that melting will not occur, (2) the possibility of material holdup by contact with the outer septifoil housing, (3) the relative shallowness of the pool `Of water into which molten material might fall, (4) the probable absence of a trigger, and (5) the relatively large energy release required to damage a nearby fuel assembly. The methodology is based upon the specification of conditions prevailing within the septifoil at the time molten material is expected to contact water, and upon information derived from the available experimental data base, supplemented by recent prototypic experiments.

  2. The steam explosion potential for an unseated SRS reactor septifoil

    Energy Technology Data Exchange (ETDEWEB)

    Allison, D.K.; Hyder, M.L.; Yau, W.W.F. (Westinghouse Savannah River Co., Aiken, SC (United States)); Smith, D.C. (Science Applications International Corp., Albuquerque, NM (United States))

    1992-01-01

    Control rods in the Savannah River Site's K Reactor are contained within housings composed of seven channels ( septifoils''). Each septifoil is suspended from the top of the reactor and is normally seated on an upflow pin that channels coolant to the septifoil. Forced flow to the septifoil would be eliminated in the unlikely event of a septifoil unseated upon installation, i.e., if the septifoil is not aligned with its upflow pin. If this event were not detected, control rod melting and the interaction of molten metal with water might occur. This paper describes a methodology used to address the issue of steam explosions that might arise by this mechanism. The probability of occurrence of a damaging steam explosion given an unseated septifoil was found to be extremely low. The primary reasons are: (1) the high probability that melting will not occur, (2) the possibility of material holdup by contact with the outer septifoil housing, (3) the relative shallowness of the pool 'Of water into which molten material might fall, (4) the probable absence of a trigger, and (5) the relatively large energy release required to damage a nearby fuel assembly. The methodology is based upon the specification of conditions prevailing within the septifoil at the time molten material is expected to contact water, and upon information derived from the available experimental data base, supplemented by recent prototypic experiments.

  3. SENTINEL EVENTS

    Directory of Open Access Journals (Sweden)

    Andrej Robida

    2004-09-01

    Full Text Available Background. The Objective of the article is a two year statistics on sentinel events in hospitals. Results of a survey on sentinel events and the attitude of hospital leaders and staff are also included. Some recommendations regarding patient safety and the handling of sentinel events are given.Methods. In March 2002 the Ministry of Health introduce a voluntary reporting system on sentinel events in Slovenian hospitals. Sentinel events were analyzed according to the place the event, its content, and root causes. To show results of the first year, a conference for hospital directors and medical directors was organized. A survey was conducted among the participants with the purpose of gathering information about their view on sentinel events. One hundred questionnaires were distributed.Results. Sentinel events. There were 14 reports of sentinel events in the first year and 7 in the second. In 4 cases reports were received only after written reminders were sent to the responsible persons, in one case no reports were obtained. There were 14 deaths, 5 of these were in-hospital suicides, 6 were due to an adverse event, 3 were unexplained. Events not leading to death were a suicide attempt, a wrong side surgery, a paraplegia after spinal anaesthesia, a fall with a femoral neck fracture, a damage of the spleen in the event of pleural space drainage, inadvertent embolization with absolute alcohol into a femoral artery and a physical attack on a physician by a patient. Analysis of root causes of sentinel events showed that in most cases processes were inadequate.Survey. One quarter of those surveyed did not know about the sentinel events reporting system. 16% were having actual problems when reporting events and 47% beleived that there was an attempt to blame individuals. Obstacles in reporting events openly were fear of consequences, moral shame, fear of public disclosure of names of participants in the event and exposure in mass media. The majority of

  4. Short-pulse shock initiation of granular explosives. [PBX-9404

    Energy Technology Data Exchange (ETDEWEB)

    Setchell, R. E.

    1981-01-01

    An experimental investigation has examined how different rates of unloading affect the release of chemical energy in a granular explosive experiencing transient shock compression. A compressed-gas gun was used to generate two types of short-pulse shocks in the explosive PBX-9404. A shock pressure of 3.2 GPa sustained for 0.37 ..mu..s was produced in both cases, but differences in flyer-plate properties resulted in different unloading histories. In one case the impact interface was rapidly unloaded by the initial release wave, while in the second case the unloading required multiple release waves over several microseconds. A VISAR system was used to observe the evolution of these two waves for distances up to 10 mm. The recorded waveforms showed that the unloading rates had a dominant effect on chemical energy release and growth towards detonation. This effect is important for considerations of critical impact criteria, and should provide a strong test for predictive shock-initiation models.

  5. Broadband seismology and the detection and verification of underground nuclear explosions

    Science.gov (United States)

    Tinker, Mark Andrew

    1997-10-01

    On September 24, 1996, President Clinton signed the Comprehensive Test Ban Treaty (CTBT), which bans the testing of all nuclear weapons thereby limiting their future development. Seismology is the primary tool used for the detection and identification of underground explosions and thus, will play a key role in monitoring a CTBT. The detection and identification of low yield explosions requires seismic stations at regional distances (nuclear testing program after a four year moratorium and conducted six tests during a five month period starting in September of 1995. Using teleseismic data, a joint hypocenter determination algorithm was used to determine the hypocenters of these six explosions. One of the most important problems in monitoring a CTBT is the detection and location of small seismic events. Although seismic arrays have become the central tool for event detection, in the context of a global monitoring treaty, there will be some dependence on sparse regional networks of three-component broadband seismic stations to detect low yield explosions. However, the full power of the data has not been utilized, namely using phases other than P and S. Therefore, the information in the surface wavetrain is used to improve the locations of small seismic events recorded on a sparse network in Bolivia. Finally, as a discrimination example in a complex region, P to S ratios are used to determine source parameters of the Msb{w} 8.3 deep Bolivia earthquake.

  6. Polarisation Spectral Synthesis For Type Ia Supernova Explosion Models

    Science.gov (United States)

    Bulla, Mattia

    2017-02-01

    Despite their relevance across a broad range of astrophysical research topics, Type Ia supernova explosions are still poorly understood and answers to the questions of when, why and how these events are triggered remain unclear. In this respect, polarisation offers a unique opportunity to discriminate between the variety of possible scenarios. The observational evidence that Type Ia supernovae are associated with rather low polarisation signals (smaller than a few per cent) places strong constraints for models and calls for modest asphericities in the progenitor system and/or explosion mechanism.The goal of this thesis is to assess the validity of contemporary Type Ia supernova explosion models by testing whether their predicted polarisation signatures can account for the small signals usually observed. To this end, we have implemented and tested an innovative Monte Carlo scheme in the radiative transfer code artis. Compared to previous Monte Carlo approaches, this technique produces synthetic observables (light curves, flux and polarisation spectra) with a substantial reduction in the Monte Carlo noise and therefore in the required computing time. This improvement is particularly crucial for our study as we aim to extract very weak polarisation signals, comparable to those detected in Type Ia supernovae. We have also demonstrated the applicability of this method to other classes of supernovae via a preliminary study of the first spectropolarimetry observations of superluminous supernovae.Using this scheme, we have calculated synthetic spectropolarimetry for three multi-dimensional explosion models recently proposed as promising candidates to explain Type Ia supernovae. Our findings highlight the power of spectropolarimetry in testing and discriminating between different scenarios. While all the three models predict light curves and flux spectra that are similar to each others and reproduce those observed in Type Ia supernovae comparably well, polarisation does

  7. Equations of state for explosive detonation products: The PANDA model

    Energy Technology Data Exchange (ETDEWEB)

    Kerley, G.I.

    1994-05-01

    This paper discusses a thermochemical model for calculating equations of state (EOS) for the detonation products of explosives. This model, which was first presented at the Eighth Detonation Symposium, is available in the PANDA code and is referred to here as ``the Panda model``. The basic features of the PANDA model are as follows. (1) Statistical-mechanical theories are used to construct EOS tables for each of the chemical species that are to be allowed in the detonation products. (2) The ideal mixing model is used to compute the thermodynamic functions for a mixture of these species, and the composition of the system is determined from assumption of chemical equilibrium. (3) For hydrocode calculations, the detonation product EOS are used in tabular form, together with a reactive burn model that allows description of shock-induced initiation and growth or failure as well as ideal detonation wave propagation. This model has been implemented in the three-dimensional Eulerian code, CTH.

  8. Event Modeling

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    2001-01-01

    The purpose of this chapter is to discuss conceptual event modeling within a context of information modeling. Traditionally, information modeling has been concerned with the modeling of a universe of discourse in terms of information structures. However, most interesting universes of discourse...... are dynamic and we present a modeling approach that can be used to model such dynamics.We characterize events as both information objects and change agents (Bækgaard 1997). When viewed as information objects events are phenomena that can be observed and described. For example, borrow events in a library can...

  9. 30 CFR 75.1314 - Sheathed explosive units.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Sheathed explosive units. 75.1314 Section 75... explosive units. (a) A separate instantaneous detonator shall be used to fire each sheathed explosive unit. (b) Sheathed explosive units shall be primed and placed in position for firing only by a qualified...

  10. Detection of Nuclear Explosions Using Infrasound Techniques

    National Research Council Canada - National Science Library

    Christie, D. R; Kennett, B. L

    2007-01-01

    The performance of typical IMS infrasound monitoring stations has been examined in detail in order to evaluate the detection capability of the global network for regional and distant nuclear explosions...

  11. Isolator fragmentation and explosive initiation tests

    Energy Technology Data Exchange (ETDEWEB)

    Dickson, Peter [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rae, Philip John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Foley, Timothy J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Novak, Alan M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Armstrong, Christopher Lee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Baca, Eva V. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gunderson, Jake Alfred [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-19

    Three tests were conducted to evaluate the effects of firing an isolator in proximity to a barrier or explosive charge. The tests with explosive were conducted without a barrier, on the basis that since any barrier will reduce the shock transmitted to the explosive, bare explosive represents the worst-case from an inadvertent initiation perspective. No reaction was observed. The shock caused by the impact of a representative plastic material on both bare and cased PBX 9501 is calculated in the worst-case, 1-D limit, and the known shock response of the HE is used to estimate minimum run-to-detonation lengths. The estimates demonstrate that even 1-D impacts would not be of concern and that, accordingly, the divergent shocks due to isolator fragment impact are of no concern as initiating stimuli.

  12. Electronic cigarette explosions involving the oral cavity.

    Science.gov (United States)

    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.

  13. Explosives Detection and Identification by PGNAA

    Energy Technology Data Exchange (ETDEWEB)

    E. H. Seabury; A. J. Caffrey

    2006-04-01

    The feasibility of using field-portable prompt gamma-ray neutron activation analysis (PGNAA) to detect and identify explosives in improvised nuclear devices has been studied computationally, using the Monte Carlo N-Particle (MCNP) code developed at Los Alamos National Laboratory. The Monte Carlo results, in turn were tested experimentally using explosive simulants and the PINS PGNAA system developed at Idaho National Laboratory (INL). The results of the MCNP calculations and PINS measurements have been previously reported. In this report we describe measurements performed on actual explosives and compare the results with calculations. The calculations and measurements were in good agreement and indicate that most explosives are readily distinguishable from one another by PGNAA

  14. Highly explosive nanosilicon-based composite materials

    Energy Technology Data Exchange (ETDEWEB)

    Clement, D.; Diener, J.; Gross, E.; Kuenzner, N.; Kovalev, D. [Technical University of Munich, Physics Department, James-Franck-Str., 85747 Garching (Germany); Timoshenko, V.Yu. [Moscow State M.V. Lomonosov University, Physics Department, 119899 Moscow (Russian Federation)

    2005-06-01

    We present a highly explosive binary system based on porous silicon layers with their pores filled with solid oxidizers. The porous layers are produced by a standard electrochemical etching process and exhibit properties that are different from other energetic materials. Its production is completely compatible with the standard silicon technology and full bulk silicon wafers can be processed and therefore a large number of explosive elements can be produced simultaneously. The application-relevant parameters: the efficiency and the long-term stability of various porous silicon/oxidizer systems have been studied in details. Structural properties of porous silicon, its surface termination, the atomic ratio of silicon to oxygen and the chosen oxidizers were optimized to achieve the highest efficiency of the explosive reaction. This explosive system reveals various possible applications in different industrial fields, e.g. as a novel, very fast airbag igniter. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. Hamiltonian approach for explosive percolation.

    Science.gov (United States)

    Moreira, A A; Oliveira, E A; Reis, S D S; Herrmann, H J; Andrade, J S

    2010-04-01

    We present a cluster growth process that provides a clear connection between equilibrium statistical mechanics and an explosive percolation model similar to the one recently proposed by D. Achlioptas [Science 323, 1453 (2009)]. We show that the following two ingredients are sufficient for obtaining an abrupt (first-order) transition in the fraction of the system occupied by the largest cluster: (i) the size of all growing clusters should be kept approximately the same, and (ii) the inclusion of merging bonds (i.e., bonds connecting vertices in different clusters) should dominate with respect to the redundant bonds (i.e., bonds connecting vertices in the same cluster). Moreover, in the extreme limit where only merging bonds are present, a complete enumeration scheme based on treelike graphs can be used to obtain an exact solution of our model that displays a first-order transition. Finally, the presented mechanism can be viewed as a generalization of standard percolation that discloses a family of models with potential application in growth and fragmentation processes of real network systems.

  16. Effects of Explosions in Underground Magazines

    Science.gov (United States)

    1989-10-01

    values of confined explosion gas pressure for PETN in air at sea level.. 23 2.3 An example of the scaling procedure employed to predict peak pressures in...compared to -thoso currently eowployed in the 1980 Department of )fise, O0D) - Amunititon and Explosivo Safety Standards (Refotetce 1). The details are...comparisons of Proctor’s (1974, Reference 5) theoretical predictions with experimontal data for TNT and PETN explosives. Stromsoo (Reference 8) calculated

  17. Non-shock initiation of explosives

    National Research Council Canada - National Science Library

    Asay, B. W

    2010-01-01

    ... explosives. Before 1942, explosives were used in munitions and commercial pursuits that demanded proper chemistry and confinement for the necessary effect, but little else. The needs and requirements of the Manhattan project were of a much more precise and specific nature. Spatial and temporal specifications were reduced from centimeters and milliseconds to micrometers and nanoseconds. New theory and computational tools were required along with a raft of new experimental techniques and novel ways of interpreting...

  18. Weapons Experiments Division Explosives Operations Overview

    Energy Technology Data Exchange (ETDEWEB)

    Laintz, Kenneth E. [Los Alamos National Laboratory

    2012-06-19

    Presentation covers WX Division programmatic operations with a focus on JOWOG-9 interests. A brief look at DARHT is followed by a high level overview of explosives research activities currently being conducted within in the experimental groups of WX-Division. Presentation covers more emphasis of activities and facilities at TA-9 as these efforts have been more traditionally aligned with ongoing collaborative explosive exchanges covered under JOWOG-9.

  19. Explosively Bonded Gun Tube Liner Development

    Science.gov (United States)

    2015-04-01

    some concern was the occasional appearance of iron-Ta intermetallics near the liner-steel interface. This is a brittle phase and subject to...Montgomery JS, de Rosset WS. Examination of intermetallic phases and residual stresses resulting from explosive bonding of refractory metal gun tube...caliber smoothbore gun tube. The metallic bond produced by explosive bonding is extremely strong and presumably would keep the liner in place. In Phase

  20. Deaths related to chemical burns.

    Science.gov (United States)

    Pavelites, Joseph J; Kemp, Walter L; Barnard, Jeffrey J; Prahlow, Joseph A

    2011-12-01

    The authors present a series of 6 deaths due to the uncommon cause of chemical burns. Of the 6 deaths due to chemical burns, 4 deaths were due to ingestion of a chemical, 1 death was caused by chemical burns of the skin, and 1 death resulted from rectal insufflation of a chemical. Seven additional cases where chemical burns may have been a contributing factor to the death or an incidental finding are also presented. Four cases are related to an incident involving chemical exposure during an industrial explosion. Three cases involve motor fuel burns of the skin. Two cases concern a plane crash incident, and 1 case involved a vehicular collision. Cases are derived from the records of the Dallas County Medical Examiner's Office and those of the authors' consultation practices. Each of the cases is presented, followed by a discussion of the various mechanisms of chemical injury.