Vulnerability of industrial facilities to attacks with improvised explosive devices aimed at triggering domino scenarios

International Nuclear Information System (INIS)

Landucci, Gabriele; Reniers, Genserik; Cozzani, Valerio; Salzano, Ernesto

2015-01-01

Process- and chemical plants may constitute a critical target for a terrorist attack. In the present study, the analysis of industrial accidents induced by intentional acts of interference is carried out focusing on accident chains triggered by attacks with home-made (improvised) explosives. The effects of blast waves caused by improvised explosive devices are compared with those expected from a net equivalent charge of TNT by using a specific methodology for the assessment of stand-off distances. It is demonstrated that a home-made explosive device has a TNT efficiency comprised between 0.2 and 0.5. The model was applied to a case study, demonstrating the potentiality of improvised explosives in causing accident escalation sequences and severe effects on population and assets. The analysis of the case-study also allowed obtaining suggestions for an adequate security management. - Highlights: • Improvised explosives possibly used for terrorist attacks were described. • The TNT efficiency of ANFO and TATP was characterized. • Domino effects caused by an attack with improvised explosive were analyzed. • Domino scenarios induced by an attack were compared to conventional scenarios

Study on film resistivity of Energy Conversion Components for MEMS Initiating Explosive Device

Science.gov (United States)

Ren, Wei; Zhang, Bin; Zhao, Yulong; Chu, Enyi; Yin, Ming; Li, Hui; Wang, Kexuan

2018-03-01

Resistivity of Plane-film Energy Conversion Components is a key parameter to influence its resistance and explosive performance, and also it has important relations with the preparation of thin film technology, scale, structure and etc. In order to improve the design of Energy Conversion Components for MEMS Initiating Explosive Device, and reduce the design deviation of Energy Conversion Components in microscale, guarantee the design resistance and ignition performance of MEMS Initiating Explosive Device, this paper theoretically analyzed the influence factors of film resistivity in microscale, through the preparation of Al film and Ni-Cr film at different thickness with micro/nano, then obtain the film resistivity parameter of the typical metal under different thickness, and reveals the effect rule of the scale to the resistivity in microscale, at the same time we obtain the corresponding inflection point data.

A portable device for fast analysis of explosives in the environment

Czech Academy of Sciences Publication Activity Database

Čapka, Lukáš; Večeřa, Zbyněk; Mikuška, Pavel; Šesták, Jozef; Kahle, Vladislav; Bumbová, A.

2015-01-01

Roč. 1388, APR (2015), s. 167-173 ISSN 0021-9673 Institutional support: RVO:68081715 Keywords : analysis of explosives * portable device * chemiluminescence detector Subject RIV: CB - Analytical Chemistry , Separation Impact factor: 3.926, year: 2015

Multi-arm multilateral haptics-based immersive tele-robotic system (HITS) for improvised explosive device disposal

Science.gov (United States)

Erickson, David; Lacheray, Hervé; Lai, Gilbert; Haddadi, Amir

2014-06-01

This paper presents the latest advancements of the Haptics-based Immersive Tele-robotic System (HITS) project, a next generation Improvised Explosive Device (IED) disposal (IEDD) robotic interface containing an immersive telepresence environment for a remotely-controlled three-articulated-robotic-arm system. While the haptic feedback enhances the operator's perception of the remote environment, a third teleoperated dexterous arm, equipped with multiple vision sensors and cameras, provides stereo vision with proper visual cues, and a 3D photo-realistic model of the potential IED. This decentralized system combines various capabilities including stable and scaled motion, singularity avoidance, cross-coupled hybrid control, active collision detection and avoidance, compliance control and constrained motion to provide a safe and intuitive control environment for the operators. Experimental results and validation of the current system are presented through various essential IEDD tasks. This project demonstrates that a two-armed anthropomorphic Explosive Ordnance Disposal (EOD) robot interface can achieve complex neutralization techniques against realistic IEDs without the operator approaching at any time.

Perspective pulse devices and automatic systems fire explosive protection of the radioactive infected objects

International Nuclear Information System (INIS)

Zakhmatov, V.D.; Kozhemyakin, A.S.; Pyatova, A.V.

1999-01-01

The suppression of fires in Chernobyl zone has shown complete unprofitable of traditional fire engineering to work on is radioactive of the infected district. In this connection as effective ways extinguishive in object 'Shelter' alongside with known traditional means and the systems offer to apply more perspective pulse systems, based on use energy small practically safe charges of gunpowder or explosive substances, in particular. Pulse explosive cone extinguishive of the device various sizes

The development of a ballistic method for simulating fragments from buried explosive devices

NARCIS (Netherlands)

Jagt-Deutekom, M.J. van der

2016-01-01

No standard scientific methodology currently exists to assess the performance of personal protection equipment (PPE) against secondary debris, such as soil, grit and stones, ejected when a buried improvised explosive device (IED) detonates. Different test methods are used for this evaluation. The

High Explosive Radiological Dispersion Device: Time and Distance Multiscale Study

International Nuclear Information System (INIS)

Sharon, A.; Sattinger, I.; Halevy, D.; Banaim, P.; Yaar, I.; Krantz, L.

2014-01-01

A wide range of explosion tests imitates different explosive RDD scenarios were conducted and aimed at increasing the preparedness for possible terrorism events, where radioactive (RA) materials disperse via an explosive charge. About 20 atmospheric dispersion tests were conducted using6-8 Ci of 99mTc which were coupled to TNT charges within the range of 0.2525 kg. Tests performed above different typical urban ground surfaces (in order to study the surface effect on the activity ground deposition pattern due to different in particles size distribution). We have used an efficient aerosolizing devices, means that most of the RA particles were initially created within the size of fine aerosols, mostly respirable. Ground activity measurements were performed both, around the dispersion point and up to few hundred meters downwind. Micrometeorology parameters (wind intensity and direction, potential temperature, relative humidity, solar radiation and atmospheric stability) were collected allowing comparisons topredictions of existing atmospheric dispersion models’1. Based on the experimental results, new model parameterizations were performed. Improvements in the models’ predictions were achieved and a set of thumb rules for first responders was formulated. This paper describes the project objectives, some of the experimental setups and results obtained. Post detonation nuclear forensic considerations can be made based upon results achieved

Methods and apparatus for field blasting of earth formations using inflatable devices for suspending explosives in boreholes

International Nuclear Information System (INIS)

Fitzgibbon, D.F. Jr.

1991-01-01

This patent describes an inflatable device for supporting a mass of stemming material or explosive material within an uncased borehole formed vertically or essentially vertically in the earth prior to initiation of blasting within the borehole, walls of the borehole being irregular due to drilling of the borehole into the earth. It comprises body means comprising flexible portions of the inflatable device for extending into contact with walls of the borehole and for transferring pressure from an inflating fluid introduced into the inflatable device to the irregular walls of the borehole, the pressure being adequate to provide an essentially vertical force component directed against the stemming material or explosive material supporting the material at a desired location within the borehole, the inflatable device being capable of inflation within the borehole; and means carried by the inflatable device for connection to a source of inflating fluid and through which the inflatable device is filled with the fluid to expand the flexible portions into engagement with the irregular walls of the borehole

Research topics in explosives - a look at explosives behaviors

International Nuclear Information System (INIS)

Maienschein, J L

2014-01-01

The behaviors of explosives under many conditions - e.g., sensitivity to inadvertent reactions, explosion, detonation - are controlled by the chemical and physical properties of the explosive materials. Several properties are considered for a range of improvised and conventional explosives. Here I compare these properties across a wide range of explosives to develop an understanding of explosive behaviors. For improvised explosives, which are generally heterogeneous mixtures of ingredients, a range of studies is identified as needed to more fully understand their behavior and properties. For conventional explosives, which are generally comprised of crystalline explosive molecules held together with a binder, I identify key material properties that determine overall sensitivity, including the extremely safe behavior of Insensitive High Explosives, and discuss an approach to predicting the sensitivity or insensitivity of an explosive.

Digital micromirror devices in Raman trace detection of explosives

Science.gov (United States)

Glimtoft, Martin; Svanqvist, Mattias; Ågren, Matilda; Nordberg, Markus; Östmark, Henric

2016-05-01

Imaging Raman spectroscopy based on tunable filters is an established technique for detecting single explosives particles at stand-off distances. However, large light losses are inherent in the design due to sequential imaging at different wavelengths, leading to effective transmission often well below 1 %. The use of digital micromirror devices (DMD) and compressive sensing (CS) in imaging Raman explosives trace detection can improve light throughput and add significant flexibility compared to existing systems. DMDs are based on mature microelectronics technology, and are compact, scalable, and can be customized for specific tasks, including new functions not available with current technologies. This paper has been focusing on investigating how a DMD can be used when applying CS-based imaging Raman spectroscopy on stand-off explosives trace detection, and evaluating the performance in terms of light throughput, image reconstruction ability and potential detection limits. This type of setup also gives the possibility to combine imaging Raman with non-spatially resolved fluorescence suppression techniques, such as Kerr gating. The system used consists of a 2nd harmonics Nd:YAG laser for sample excitation, collection optics, DMD, CMOScamera and a spectrometer with ICCD camera for signal gating and detection. Initial results for compressive sensing imaging Raman shows a stable reconstruction procedure even at low signals and in presence of interfering background signal. It is also shown to give increased effective light transmission without sacrificing molecular specificity or area coverage compared to filter based imaging Raman. At the same time it adds flexibility so the setup can be customized for new functionality.

Electromagnetic coupling between transmitters and electro-explosive devices located within an enclosure.

Energy Technology Data Exchange (ETDEWEB)

Warne, Larry Kevin; Jorgenson, Roy Eberhardt; Coats, Rebecca Sue

2010-04-01

This report documents calculations conducted to determine if 42 low-power transmitters located within a metallic enclosure can initiate electro-explosive devices (EED) located within the same enclosure. This analysis was performed for a generic EED no-fire power level of 250 mW. The calculations show that if the transmitters are incoherent, the power available is 32 mW - approximately one-eighth of the assumed level even with several worst-case assumptions in place.

Gas explosion in domestic buildings. The vented gas explosion[sub][/sub

Directory of Open Access Journals (Sweden)

Tadeusz Chyży

2014-08-01

Full Text Available In this paper, the basic information, related to the so-called vented gas explosion, has been presented. The vented explosion it is an explosion, during which the destruction of the weakest elements of the structure occurs. Through the resulting holes (decompressing surfaces can flow both combustion products and non-burned gas mixture. In consequence, reduction of the maximum explosion pressure[i] P[sub]red [/sub][/i] may be significant. Often, a gas explosion occurs inside residential buildings. In this case, natural vents are window and door openings.[b]Keywords[/b]: gas, explosion, combustion, explosion vents

Green primary explosives: 5-Nitrotetrazolato-N2-ferrate hierarchies

OpenAIRE

Huynh, My Hang V.; Coburn, Michael D.; Meyer, Thomas J.; Wetzler, Modi

2006-01-01

The sensitive explosives used in initiating devices like primers and detonators are called primary explosives. Successful detonations of secondary explosives are accomplished by suitable sources of initiation energy that is transmitted directly from the primaries or through secondary explosive boosters. Reliable initiating mechanisms are available in numerous forms of primers and detonators depending upon the nature of the secondary explosives. The technology of initiation devices used for mi...

Wireless sensor for detecting explosive material

Science.gov (United States)

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

2014-10-28

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

Do peaceful nuclear explosions have a future

International Nuclear Information System (INIS)

Anon.

1988-01-01

The idea of peaceful uses for nuclear explosive devices arose almost simultaneously with the concept of the nuclear explosion itself. It has been a powerful idea in that it soon generated major study efforts in the United States and the USSR and also captured the interest of many developing nations. But in spite of this considerable interest and much expenditure of funds and effort, the expectation that economically viable uses will be found for peaceful nuclear explosions looks even more distant now that when the first studies were initiated. This, at least, is the conclusion of two recent U.S. studies of the economic feasibility and time scale for application of peaceful nuclear explosions by the United States. The larger of these two studies was prepared by the Gulf Universities Research Consortium, and dealt particularly with possibilities for use in the United States by 1990 of contained, i.e., underground, peaceful nuclear explosions. This paper provides briefer analysis by an ad hoc panel assesses the implications of the Gulf report, considers other uses for peaceful nuclear explosions, and summarizes the reasons why there is only a small possibility that there will be significant use of them by the United States before the year 2000

Nuclear explosives and hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Cohen, P

1971-10-01

A nuclear explosive 12 in. in diam and producing very little tritium is feasible in France. Such a device would be well adapted for contained nuclear explosions set off for the purpose of hydrocarbon storage or stimulation. The different aspects of setting off the explosive are reviewed. In the particular case of gas storage in a nuclear cavity in granite, it is demonstrated that the dose of irradiation received is extremely small. (18 refs.)

Multilateral haptics-based immersive teleoperation for improvised explosive device disposal

Science.gov (United States)

Erickson, David; Lacheray, Hervé; Daly, John

2013-05-01

Of great interest to police and military organizations is the development of effective improvised explosive device (IED) disposal (IEDD) technology to aid in activities such as mine field clearing, and bomb disposal. At the same time minimizing risk to personnel. This paper presents new results in the research and development of a next generation mobile immersive teleoperated explosive ordnance disposal system. This system incorporates elements of 3D vision, multilateral teleoperation for high transparency haptic feedback, immersive augmented reality operator control interfaces, and a realistic hardware-in-the-loop (HIL) 3D simulation environment incorporating vehicle and manipulator dynamics for both operator training and algorithm development. In the past year, new algorithms have been developed to facilitate incorporating commercial off-the-shelf (COTS) robotic hardware into the teleoperation system. In particular, a real-time numerical inverse position kinematics algorithm that can be applied to a wide range of manipulators has been implemented, an inertial measurement unit (IMU) attitude stabilization system for manipulators has been developed and experimentally validated, and a voice­operated manipulator control system has been developed and integrated into the operator control station. The integration of these components into a vehicle simulation environment with half-car vehicle dynamics has also been successfully carried out. A physical half-car plant is currently being constructed for HIL integration with the simulation environment.

CFD analysis of gas explosions vented through relief pipes.

Science.gov (United States)

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

2006-09-21

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

Detection of chemical explosives using multiple photon signatures

International Nuclear Information System (INIS)

Loschke, K.W.; Dunn, W.L.

2008-01-01

Full text: A template-matching procedure to aid in rapid detection of improvised explosive devices (IEDs) is being investigated. Multiple photon-scattered and photon-induced positron annihilation radiation responses are being used as part of a photon-neutron signature-based radiation scanning (SBRS) approach (see companion reference for description of the neutron component), in an attempt to detect chemical explosives at safe standoff distances. Many past and present photon interrogation methods are based on imaging. Imaging techniques seek to determine at high special resolution the internal structure of a target of interest. Our technique simply seeks to determine if an unknown target contains a detectable amount of chemical explosives by comparing multiple responses (signatures) that depend on both density and composition of portions of a target. In the photon component, beams of photons are used to create back-streaming signatures, which are dependent on the density and composition of part of the target being interrogated. These signatures are compared to templates, which are collections of the same signatures if the interrogated volume contained a significant amount of explosives. The signature analysis produces a figure-of-merit and a standard deviation of the figure-of-merit. These two metrics are used to filter safe from dangerous targets. Experiments have been conducted that show that explosive surrogates (fertilizers) can be distinguished from several inert materials using these photon signatures, demonstrating that these signatures can be used effectively to help IEDs

Filling bore-holes with explosive

Energy Technology Data Exchange (ETDEWEB)

Alfredsson, S H

1965-03-02

In this device for filling boreholes formed in a rock formation with particulate explosive, the explosive is conveyed into the hole by means of a pressure fluid through a tube which has a lesser diameter than the hole. The tube is characterized by a lattice work arranged externally on it, and having a structure adapted to allow passage of a pressure fluid returning between the tube and the wall of the hole, but retaining particles of explosive entrained by the returning pressure fluid. In another arrangement of the device, the lattice work has the form of a brush, including filaments or bristles which are dimensioned to bridge the spacing between the tube and the wall of the hole. (12 claims)

Improved Overpressure Recording and Modeling for Near-Surface Explosion Forensics

Science.gov (United States)

Kim, K.; Schnurr, J.; Garces, M. A.; Rodgers, A. J.

2017-12-01

The accurate recording and analysis of air-blast acoustic waveforms is a key component of the forensic analysis of explosive events. Smartphone apps can enhance traditional technologies by providing scalable, cost-effective ubiquitous sensor solutions for monitoring blasts, undeclared activities, and inaccessible facilities. During a series of near-surface chemical high explosive tests, iPhone 6's running the RedVox infrasound recorder app were co-located with high-fidelity Hyperion overpressure sensors, allowing for direct comparison of the resolution and frequency content of the devices. Data from the traditional sensors is used to characterize blast signatures and to determine relative iPhone microphone amplitude and phase responses. A Wiener filter based source deconvolution method is applied, using a parameterized source function estimated from traditional overpressure sensor data, to estimate system responses. In addition, progress on a new parameterized air-blast model is presented. The model is based on the analysis of a large set of overpressure waveforms from several surface explosion test series. An appropriate functional form with parameters determined empirically from modern air-blast and acoustic data will allow for better parameterization of signals and the improved characterization of explosive sources.

Inadequate peak expiratory flow meter characteristics detected by a computerised explosive decompression device

DEFF Research Database (Denmark)

Miller, M.R.; Atkins, P.R.; Pedersen, O.F.

2003-01-01

Methods: The dynamic response of mini-Wright (MW), Vitalograph (V), TruZone (TZ), MultiSpiro (MS) and pneumotachograph (PT) flow meters was tested by delivering two differently shaped flow-time profiles from a computer controlled explosive decompression device fitted with a fast response solenoid.......1) and 257 (39.2), respectively, and at ≈200 l/min they were 51 (23.9) and 1 (0.5). All the meters met ATS accuracy requirements when tested with their waveforms. Conclusions: An improved method for testing the dynamic response of flow meters detects marked overshoot (underdamping) of TZ and MS responses...

Front to back ocular injury from a vaping-related explosion.

Science.gov (United States)

Khairudin, Muhammad Najmi; Mohd Zahidin, Aida Zairani; Bastion, Mae-Lynn Catherine

2016-04-05

We describe a case of extensive ocular injury secondary to an electronic cigarette (e-cigarette)-related explosion. The explosion was the result of modifications made to a heating element of the e-cigarette device by a non-professional. Extensive ocular injuries that result from an explosion of an e-cigarette device can potentially cause significant and permanent visual impairment. 2016 BMJ Publishing Group Ltd.

Fizičko-hemijske i detonacione karakteristike nitraminskih eksploziva - RDX, HMX i CL-20 / Physico-chemical and detonation properties of nitramine explosives: RDX, HMX and CL-20

Directory of Open Access Journals (Sweden)

Mirjana Anđelković-Lukić

2002-11-01

Full Text Available U radu su prikazane fizičko-hemijske i detonacione karakteristike nitraminskih brizantnih eksploziva, heksogena i oktogena, uporedene sa osobinama novog cikličnog nitraminskog eksploziva CL-20. Novi visokobrizantni eksploziv CL-20 postoji u četiri kristalne forme, stabilne na različitim temepraturama. Ima bolje detonacione karakteristike od heksogena i oktogena veću gustinu i brzinu detonacije, all mnogo veću osetljivost na udar i trenje, reda PETN. Zbog toga se ovaj eksploziv flegmatizuje sa polimerima etilenvinilacetatom (EVA i estanom. Da bi se povećale energetske performanse eksploziva i smanjila osetljivost na mehanička dejstva eksplozivu CL-20 dodaju se visokoenergetski materijali, fluoronitrojedinjenja (FEFO. / In this paper the physico-chemical and detonation properties of nitramine high explosives, hexogen and octogen, are presented and compared with a polycyclic nitramine high explosive CL-20. This new high explosive CL-20 exists in four crystalline forms, stable at different temperatures. CL-20 has better detonation properties than hexogen and octogen, higher density and detonation rate, but greater impact and friction sensitivity (of PETN class. So it is necessary to bond this explosive with polymers-ethylenvinil acetat (EVA and estane to reduce sensitivity to mechanical effects. CL-20 can be prepared by adding high energy materials-fluoro-nitro compounds (FEFO as regulators of energy performances.

[Emotional Profile of a Group of Colombian Military Victims of Landmines or Improvised Explosive Devices].

Science.gov (United States)

Restrepo, Jorge Emiro; Yara, Eduardo Alfonso; Cano Betancur, Jessica; Tavera, Luz Navia

2014-01-01

Antipersonnel Mines (MAP) and Improvised Explosive Devices (IEDs) are frequently used in Colombia as an armed resource without the need for direct combat. The Department of Antioquia has the highest number of events associated with the detonation of such battle techniques. There are no studies on the psychological effects that appear as a result of accidents with Antipersonnel Mines and IEDs in the military population. To establish the psychological profile of a group of military victims of MAP and AEI, and a control group of soldiers who were not victims from the analysis of four emotional variables (depression, anxiety, anger and stress). The research was conducted using a case-control design in a .quantitative, comparative, descriptive and cross-sectional study. A sample of 80 soldiers assigned to the Seventh Division of the National Army of Colombia at Medellin, Antioquia. The sample included a group of 30 military cases and 50 soldiers as controls. The anxiety state, trait anxiety, state anger, and trait anger variables showed statistically significant differences between groups. There were no significant differences in the variables depression and stress between groups variables. There was no depression, anxiety, or stress in either of the two groups, but there were clinically significant levels of anger in both groups. Copyright © 2013 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

Using of explosive technologies for development of a compact current-limiting device for operation on 110 kV class systems

Science.gov (United States)

Shurupov, A. V.; Shurupov, M. A.; Kozlov, A. A.; Kotov, A. V.

2016-11-01

This paper considers the possibility of creating on new physical principles a highspeed current-limiting device (CLD) for the networks with voltage of 110 kV, namely, on the basis of the explosive switching elements. The device is designed to limit the steady short-circuit current to acceptable values for the time does not exceed 3 ms at electric power facilities. The paper presents an analysis of the electrical circuit of CLD. The main features of the scheme are: a new high-speed switching element with high regenerating voltage; fusible switching element that enables to limit the overvoltage after sudden breakage of network of the explosive switch; non-inductive resistor with a high heat capacity and a special reactor with operating time less than 1 s. We analyzed the work of the CLD with help of special software PSPICE, which is based on the equivalent circuit of single-phase short circuit to ground in 110 kV network. Analysis of the equivalent circuit operation CLD shows its efficiency and determines the CLD as a perspective direction of the current-limiting devices of new generation.

Using of explosive technologies for development of a compact current-limiting device for operation on 110 kV class systems

International Nuclear Information System (INIS)

Shurupov, A V; Shurupov, M A; Kozlov, A A; Kotov, A V

2016-01-01

This paper considers the possibility of creating on new physical principles a highspeed current-limiting device (CLD) for the networks with voltage of 110 kV, namely, on the basis of the explosive switching elements. The device is designed to limit the steady short-circuit current to acceptable values for the time does not exceed 3 ms at electric power facilities. The paper presents an analysis of the electrical circuit of CLD. The main features of the scheme are: a new high-speed switching element with high regenerating voltage; fusible switching element that enables to limit the overvoltage after sudden breakage of network of the explosive switch; non-inductive resistor with a high heat capacity and a special reactor with operating time less than 1 s. We analyzed the work of the CLD with help of special software PSPICE, which is based on the equivalent circuit of single-phase short circuit to ground in 110 kV network. Analysis of the equivalent circuit operation CLD shows its efficiency and determines the CLD as a perspective direction of the current-limiting devices of new generation. (paper)

Sinteza i fizičko-hemijske karakteristike eksploziva HNIW (CL-20 / Synthesis and physicochemical properties of the HNIW (CL-20 explosive

Directory of Open Access Journals (Sweden)

Mirjana Lukić-Anđelković

2009-04-01

Full Text Available Novo jedinjenje CL-20 je ciklični nitramin sa najvećom kristalnom gustinom (iznad 2,0 g/cm3 i najsnažniji nenuklearni eksploziv. Opisana je sinteza HNIW ili CL-20 u tri stepena. CL-20 ima najveću gustinu i brzinu detonacije među poznatim eksplozivima, kao i najveću energiju među energetskim dodacima koji se koriste kao dodaci za eksplozive, barute i kompozitna raketna goriva. Prikazani su neki sastavi na bazi CL-20, energetskih polimera, aluminijuma i amonijumperhlorata, kao i gustine i brzine njihove detonacije. / The new compound CL-20, a cyclic nitramine with the highest crystal density (over 2.0 g/cm3, is the most powerful non-nuclear explosive. The three-step synthesis of hexanitrohexaazaisowurtzitane (HNIW or CL-20 has been described. The CL-20 has the highest density and the highest detonation velocity among existing explosives as well as the highest energy among existing energetic ingredients for explosives, gun propellants and rocket propellants. Same explosive formulations based on the CL-20, energetic polymers, aluminium and ammoniumperchlorate are presented. Their densities and detonation velocities are also presented.

Vapor generation methods for explosives detection research

Energy Technology Data Exchange (ETDEWEB)

Grate, Jay W.; Ewing, Robert G.; Atkinson, David A.

2012-12-01

The generation of calibrated vapor samples of explosives compounds remains a challenge due to the low vapor pressures of the explosives, adsorption of explosives on container and tubing walls, and the requirement to manage (typically) multiple temperature zones as the vapor is generated, diluted, and delivered. Methods that have been described to generate vapors can be classified as continuous or pulsed flow vapor generators. Vapor sources for continuous flow generators are typically explosives compounds supported on a solid support, or compounds contained in a permeation or diffusion device. Sources are held at elevated isothermal temperatures. Similar sources can be used for pulsed vapor generators; however, pulsed systems may also use injection of solutions onto heated surfaces with generation of both solvent and explosives vapors, transient peaks from a gas chromatograph, or vapors generated by s programmed thermal desorption. This article reviews vapor generator approaches with emphasis on the method of generating the vapors and on practical aspects of vapor dilution and handling. In addition, a gas chromatographic system with two ovens that is configurable with up to four heating ropes is proposed that could serve as a single integrated platform for explosives vapor generation and device testing. Issues related to standards, calibration, and safety are also discussed.

Surface motion near underground nuclear explosions in desert alluvium Operation Nougat I, Area 3, Nevada Test Site

International Nuclear Information System (INIS)

Perret, W.R.

1978-05-01

During Operation Nougat I, which was conducted in late 1961 and the first half of 1962, Sandia Laboratories measured surface motion in the vicinity of all contained underground nuclear explosions conducted by the Los Alamos Scientific Laboratory in Area 3 of the Nevada Test Site. This report presents and analyses most of the data derived from that study. Propagation velocities in the desert alluvium, 4440 ft/sec, and underlying tuff, 6020 ft/sec, are typical of those derived from later measurements. Motion attenuation data exhibit considerable scatter, in part because of early measurement and data reduction techniques but primarily because of differences in the characteristics of the geologic media which had not then been recognized. However, regression fits to the scaled data show attenuation of scaled acceleration at a rate 35% greater than that observed for Merlin event data (Merlin was conducted later in Area 3). The attenuation rate for particle velocity data from Nougat I events was 47% less than that for Merlin data, and the Nougat I scaled displacement data attenuation rate was 87% less than that for Merlin data. Analysis of data from a vertical string of gages extending to the surface above the Mink explosion has established a significant difference between normal spallation above contained explosions in competent rock and the reaction of uncemented alluvium to similar explosive loading

Identification of inorganic improvised explosive devices by analysis of postblast residues using portable capillary electrophoresis instrumentation and indirect photometric detection with a light-emitting diode.

Science.gov (United States)

Hutchinson, Joseph P; Evenhuis, Christopher J; Johns, Cameron; Kazarian, Artaches A; Breadmore, Michael C; Macka, Miroslav; Hilder, Emily F; Guijt, Rosanne M; Dicinoski, Greg W; Haddad, Paul R

2007-09-15

A commercial portable capillary electrophoresis (CE) instrument has been used to separate inorganic anions and cations found in postblast residues from improvised explosive devices (IEDs) of the type used frequently in terrorism attacks. The purpose of this analysis was to identify the type of explosive used. The CE instrument was modified for use with an in-house miniaturized light-emitting diode (LED) detector to enable sensitive indirect photometric detection to be employed for the detection of 15 anions (acetate, benzoate, carbonate, chlorate, chloride, chlorite, cyanate, fluoride, nitrate, nitrite, perchlorate, phosphate, sulfate, thiocyanate, thiosulfate) and 12 cations (ammonium, monomethylammonium, ethylammonium, potassium, sodium, barium, strontium, magnesium, manganese, calcium, zinc, lead) as the target analytes. These ions are known to be present in postblast residues from inorganic IEDs constructed from ammonium nitrate/fuel oil mixtures, black powder, and chlorate/perchlorate/sugar mixtures. For the analysis of cations, a blue LED (470 nm) was used in conjunction with the highly absorbing cationic dye, chrysoidine (absorption maximum at 453 nm). A nonaqueous background electrolyte comprising 10 mM chrysoidine in methanol was found to give greatly improved baseline stability in comparison to aqueous electrolytes due to the increased solubility of chrysoidine and its decreased adsorption onto the capillary wall. Glacial acetic acid (0.7% v/v) was added to ensure chrysoidine was protonated and to enhance separation selectivity by means of complexation with transition metal ions. The 12 target cations were separated in less than 9.5 min with detection limits of 0.11-2.30 mg/L (calculated at a signal-to-noise ratio of 3). The anions separation system utilized a UV LED (370 nm) in conjunction with an aqueous chromate electrolyte (absorption maximum at 371 nm) consisting of 10 mM chromium(VI) oxide and 10 mM sodium chromate, buffered with 40 mM tris

36 CFR 327.13 - Explosives, firearms, other weapons and fireworks.

Science.gov (United States)

2010-07-01

... weapons and fireworks. 327.13 Section 327.13 Parks, Forests, and Public Property CORPS OF ENGINEERS... ADMINISTERED BY THE CHIEF OF ENGINEERS § 327.13 Explosives, firearms, other weapons and fireworks. (a) The... explosives or explosive devices of any kind, including fireworks or other pyrotechnics, is prohibited unless...

Inexpensive semi-autonomous ground vehicles for defusing IEDs

Science.gov (United States)

Davenport, Chris; Lodmell, James; Womble, Phillip C.; Barzilov, Alexander; Paschal, Jon; Hernandez, Robert; Moss, Kyle T.; Hopper, Lindsay

2008-04-01

Improvised explosive devices (IEDs) are an important concern to coalition forces during the conflicts in the Middle East. These devices are responsible for many casualties to American armed forces in the Middle East. These explosives are particularly dangerous because they are improvised with materials readily available to the designer, and there is no systematic way of explosive ordinance disposal. IEDs can be made from things such as standard military ammunition and can be detonated with common electronic devices such as cell phones and garage door openers. There is a great need for a low cost solution to neutralize these IEDs. At the Applied Physics Institute we are building a single function disrupter robot whose sole purpose is to neutralize these IEDs. We are modifying a toy remote control car to control it either wirelessly using WI-FI (IEEE 802.11) or wired by tethering the vehicle with an Ethernet cable (IEEE 802.3). The robot will be equipped with a high velocity fuze disrupter to neutralize the IED as well as a video camera for inspection and aiming purposes. This robot utilizes commercial-off-the-shelf (COTS) components which keeps the cost relatively low. Currently, similar robot systems have been deployed in Iraq and elsewhere but their method of operation is such that it is impractical to use in non-combat situations. We will discuss our design and possible deployment scenarios.

Methane Explosion Mitigation in Coal Mines by Water Mist

Science.gov (United States)

Chikhradze, Nikoloz; Mataradze, Edgar; Chikhradze, Mikheil; Krauthammer, Ted; Mansurov, Zulkhair; Alyiev, Erhan

2017-12-01

Statistics shows that the majority of accidents with fatal outcome are caused by methane and/or coal dust explosion. This leads to assume that contemporary counter-explosion systems of various designs cannot be considered effective. Considering the growing threat of methane explosion in the coming years along with the development of deeper levels, the improvement of a system for protecting people in underground opening appears urgent. This paper focuses on technical solutions to be used in designing a protective system for minimizing the consequences of methane explosions in coalmines. The new protective system consists of three main modules: i) a high-speed shock wave suppression section; ii) a suppression section with a long-term action and iii) a system activating device. The shock wave suppressor contains a 200 litre volume water tank with a built-in gas generator and nozzles. It is activated after 12ms from the blast moment, the duration of discharge is 40 s. The suppression section with a long-term action contains a 2000 litre volume water tank, a high-pressure pump, a hydraulic accumulator, solenoid valves, and a system of pipes with built-in nozzles. It is activated after 4 s from the blast moment, the duration of discharge is 8 min. The activation device includes a detection block containing sensors, an emergency signal generation module, a signal transmission module, a signal receiving module and a power supply module. The system operates in a waiting mode and activates immediately upon the receipt of the start signal generated by the detector. The paper also addresses the preliminary results of the system prototype testing in the tunnel.

Decreasing Friction Sensitivity for Primary Explosives

Science.gov (United States)

Matyáš, Robert; Šelešovský, Jakub

2014-04-01

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

Oral Trauma and Tooth Avulsion Following Explosion of E-Cigarette.

Science.gov (United States)

Rogér, James M; Abayon, Maricelle; Elad, Sharon; Kolokythas, Antonia

2016-06-01

Electronic cigarettes (E-cigarettes), or personal vaporizers, were introduced in 2003 and have been available in the United States since 2007. In addition to the health and safety concerns of the aerosol delivery of nicotine through E-cigarettes, during the past 8 years, reports of explosions and fires caused by the E-cigarette devices have led the US Fire Administration to evaluate the safety of these devices. These explosions have been observed frequently enough that the US Department of Transportation has recently banned E-cigarette devices in checked baggage aboard airplanes. This report contributes to existing knowledge about the hazards related to E-cigarettes by describing oral hard and soft tissue injuries from an E-cigarette explosion. Copyright © 2016 The American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Common Chemicals as Precursors of Improvised Explosive Devices: The Challenges of Controlling Domestic Terrorism

National Research Council Canada - National Science Library

Rostberg, James I

2005-01-01

...). Explosives in the hands of terrorists continue to pose a significant threat. Lessons learned indicate that when traditional explosives become difficult to obtain, bomb makers turn to common chemicals as precursors to manufacture explosives...

Neutron albedo effects of underground nuclear explosion

International Nuclear Information System (INIS)

Yang Bo; Ying Yangjun; Li Jinhong; Bai Yun

2013-01-01

The neutron field distribution is affected by the surrounding medium in the underground nuclear explosion. It will influence the radiation chemical diagnosis. By Monte Carlo simulation, the fuel burnup induced by device and neutron albedo was calculated. The analysis method of albedo effect on radiation chemical diagnosis result under special environment was proposed. Neutron albedo should be considered when capture reaction burnup fraction is used, and then correct analysis can be carried out on the nuclear device.The neutron field distribution is affected by the surrounding medium in the underground nuclear explosion. It will influence the radiation chemical diagnosis. By Monte Carlo simulation, the fuel burnup induced by device and neutron albedo was calculated. The analysis method of albedo effect on radiation chemical diagnosis result under special environment was proposed. Neutron albedo should be considered when capture reaction burnup fraction is used, and then correct analysis can be carried out on the nuclear device. (authors)

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.

Detection of Materials Used for Improvised Explosive Devices Employing D-T (14 MeV) Neutron Source

International Nuclear Information System (INIS)

Shyam, Anurag; Sharma, Surender Kumar; Das, Basanta

2010-01-01

There is an increased use of improvised explosive devices (IED), especially for human targets. One of the substances used in these devices is ammonium nitrate. Since this IED substance also contains elements - hydrogen (H), carbon (C), nitrogen (N), oxygen (O). The elemental density (of H, C, O, and N) and elemental density ratio (C/O, N/O, H/N etc) can be used to differentiate it from other substances. Neutrons based techniques are one of the methods for non-destructive these elemental characterization. For our experiments we are using two sealed neutron tubes. First tubes can produce 10 8 (maximum) D-T neutrons in ∼0.8 μs pulse and 100 (maximum) pulses can be generated per second. Second tube can produce (maximum) 10 10 D-T neutrons/s. The neutron output can be pulsed. Pulses of 1.5 μs duration and pulse repetition rate of 10 Hz to 10 kHz can be obtained. D-T neutrons pulses are impinged on ammonium nitrate samples (0.5 to 1.5 kg) and resultant gamma rays (prompt and due to activation) are recorded using sodium iodide (NaI) and bismuth germanium orthosilicate (BGO) scintillation detectors. To facilitate recording of high count rate a 2 GS/s high speed digitizer with large on board memory and high transfer rate has been used (instead of conventional multi channel analyzer). Preliminary results and analysis will be presented at the conference. To further refine the technique we are also developing a D-T neutron generator with associated particle detection facility. For this system we have already developed a penning ion source and a 140 kV battery operated SMPS. (author)

Techniques for detecting explosives and contraband

International Nuclear Information System (INIS)

Vourvopoulos, G.

1994-01-01

Because terrorism continues to be a societal threat, scientists are still searching for ways to identify concealed weapons that can be used in terrorist attacks. Explosives are singled out for particular attention because they can easily be shaped to look innocuous, and are still hard to detect. At present, there are three methods under development for the detection of explosives: X-ray imaging, vapour detection and nuclear techniques, and this article will concentrate on the latter. Since there is no single technology that can address all the questions concerning the detection of explosives and other illicit contraband, the philosophy that emerges is that of an integral system combining methodologies. Such a system could contain a nuclear technology device, a vapour detector, and an X-ray imaging device, all backed by an intelligence gathering system. In this paper methods are suggested for identifying explosives which may be used in terrorist attacks and for detecting concealed drugs. Techniques discussed are X-ray imaging, combining high and low energy x-ray machines, vapour detection using a ''sniffer'' to collect vapour samples then analysing the vapour by gas chromatography, chemiluminescence and mass spectroscopy and nuclear techniques. Nuclear techniques, such as neutron activation analysis, are discussed in detail but it is stressed that they need to be carried out at speed to eliminate disruption and delay at airports etc. (UK)

Research and Development of a portable microfocus x-ray system capable of providing ultra-high resolutions images of improvised explosive devices

International Nuclear Information System (INIS)

Korkala, G.

1989-01-01

The utilization of x-ray screening has long been a recognized valuable tool as a means to evaluate and identify suspect articles for possible improvised explosive devices. Recent bombings indicate an increase in technical sophistication by the terrorist which demand additional means to further the possibility of detecting these devices before they reach their target or detonate. This paper discusses history of the use of x-ray and the design parameters of a portable micro-focus x-ray system capable of providing ultra high resolution radiographs as well as being able to be used with additional state-of-the-art imaging systems

Screening sealed bottles for liquid explosives

Science.gov (United States)

Kumar, Sankaran; McMichael, W. Casey; Kim, Y.-W.; Sheldon, Alan G.; Magnuson, Erik E.; Ficke, L.; Chhoa, T. K.; Moeller, C. R.; Barrall, Geoffrey A.; Burnett, Lowell J.; Czipott, Peter V.; Pence, J. S.; Skvoretz, David C.

1997-01-01

A particularly disturbing development affecting transportation safety and security is the increasing use of terrorist devices which avoid detection by conventional means through the use of liquid explosives and flammables. The hazardous materials are generally hidden in wine or liquor bottles that cannot be opened routinely for inspection. This problem was highlighted by the liquid explosives threat which disrupted air traffic between the US an the Far East for an extended period in 1995. Quantum Magnetics has developed a Liquid Explosives Screening systems capable of scanning unopened bottles for liquid explosives. The system can be operated to detect specific explosives directly or to verify the labeled or bar-coded contents of the container. In this system, magnetic resonance (MR) is used to interrogate the liquid. MR produces an extremely rich data set and many characteristics of the MR response can be determined simultaneously. As a result, multiple MR signatures can be defined for any given set of liquids, and the signature complexity then selected according to the level of threat. The Quantum Magnetics Liquid Explosives Screening System is currently operational. Following extensive laboratory testing, a field trial of the system was carried out at the Los Angeles International Airport.

Underground nuclear explosions. Study of the cavity radius

International Nuclear Information System (INIS)

Michaud, L.

1968-11-01

An underground nuclear explosion creates a cavity due to the expansion of the surrounding medium vaporized by the shot. The cavity radius is related to the energy of explosion and to the overburden pressure of the medium. The introduction of new elements such as the environment of the device (in a deep hole or in a tunnel) and the cohesion of the medium leads to a relationship which determines this radius. The known French and American underground explosions performed in various media, energy and overburden conditions, satisfy this relationship with a good precision. (author) [fr

49 CFR 173.54 - Forbidden explosives.

Science.gov (United States)

2010-10-01

... dimension of which exceeds 23 mm (0.906 inch), or a toy torpedo containing a mixture of potassium chlorate... subpart. (b) An explosive mixture or device containing a chlorate and also containing: (1) An ammonium...

Application of factor analysis to the explosive detection

International Nuclear Information System (INIS)

Park, Yong Joon; Song, Byung Chul; Im, Hee Jung; Kim, Won Ho; Cho, Jung Hwan

2005-01-01

The detection of explosive devices hidden in airline baggage is significant problem, particularly in view of the development of modern plastic explosives which can formed into various innocent-appearing shapes and which are sufficiently powerful that small quantities can destroy an aircraft in flight. Besides, the biggest difficulty occurs from long detection time required for the explosive detection system based on thermal neutron interrogation, which involves exposing baggage to slow neutrons having energy in the order of 0.025 eV. The elemental compositions of explosives can be determined by the Neutron Induced Prompt gamma Spectroscopy (NIPS) which has been installed in Korea Atomic Energy Research Institute as a tool for the detection of explosives in passenger baggage. In this work, the factor analysis has been applied to the NIPS system to increase the signal-to-noise ratio of the prompt gamma spectrum for the detection of explosive hidden in a passenger's baggage, especially for the noisy prompt gamma spectrum obtained with short measurement time

Idaho Explosives Detection System

International Nuclear Information System (INIS)

Reber, Edward L.; Blackwood, Larry G.; Edwards, Andrew J.; Jewell, J. Keith; Rohde, Kenneth W.; Seabury, Edward H.; Klinger, Jeffery B.

2005-01-01

The Idaho Explosives Detection System was developed at the Idaho National Laboratory (INL) to respond to threats imposed by delivery trucks potentially carrying explosives into military bases. A full-scale prototype system has been built and is currently undergoing testing. The system consists of two racks, one on each side of a subject vehicle. Each rack includes a neutron generator and an array of NaI detectors. The two neutron generators are pulsed and synchronized. A laptop computer controls the entire system. The control software is easily operable by minimally trained staff. The system was developed to detect explosives in a medium size truck within a 5-min measurement time. System performance was successfully demonstrated with explosives at the INL in June 2004 and at Andrews Air Force Base in July 2004

Idaho Explosives Detection System

Energy Technology Data Exchange (ETDEWEB)

Reber, Edward L. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States)]. E-mail: reber@inel.gov; Blackwood, Larry G. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States); Edwards, Andrew J. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States); Jewell, J. Keith [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States); Rohde, Kenneth W. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States); Seabury, Edward H. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States); Klinger, Jeffery B. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States)

2005-12-15

The Idaho Explosives Detection System was developed at the Idaho National Laboratory (INL) to respond to threats imposed by delivery trucks potentially carrying explosives into military bases. A full-scale prototype system has been built and is currently undergoing testing. The system consists of two racks, one on each side of a subject vehicle. Each rack includes a neutron generator and an array of NaI detectors. The two neutron generators are pulsed and synchronized. A laptop computer controls the entire system. The control software is easily operable by minimally trained staff. The system was developed to detect explosives in a medium size truck within a 5-min measurement time. System performance was successfully demonstrated with explosives at the INL in June 2004 and at Andrews Air Force Base in July 2004.

Improvised Explosive Devices (IEDs) in Iraq and Afghanistan: Effects and Countermeasures

National Research Council Canada - National Science Library

Wilson, Clay

2006-01-01

.... IEDs are hidden behind signs and guardrails, under roadside debris, or inside animal carcasses, and encounters with these bombs are becoming more numerous and deadly in both Iraq and Afghanistan...

Explosion-protected electric heating systems

Energy Technology Data Exchange (ETDEWEB)

Elsner, H

1984-02-01

Different constructions of explosion-protected heating systems are described concerning the different types of protection, the service conditions, the installation and the surveillance devices. Interpretations and regulations derived from the VDE Standards are discussed and their relation to the European Standards EN 50014 ... 50020 is considered in a survey.

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.

Book Review: iPhone and iOS Forensic: Investigation, Analysis and Mobile Security for Apple iPhone, iPad and iOS Devices

OpenAIRE

Garfinkel, Simson

2013-01-01

Hoog, A., & Strzempka, K. (2011). iPhone and iOS Forensics: Investigation, Analysis and Mobile Security for Apple iPhone, iPad and iOS Devices. Waltham, MA: Syngress. 336 pages, ISBN: 978-1-59749-659-9, US$69.95.Reviewed by Christopher Schulte, EnCE & ACE, LuciData Inc., Minneapolis, Minnesota ()These are exciting times for Digital Forensics practitioners. While our examinations of mobile devices (including cell phones and tablet computers) continue to bring ne...

Book Review: iPhone and iOS Forensics: Investigation, Analysis and Mobile Security for Apple iPhone, iPad and iOS Devices

OpenAIRE

Schulte Christopher

2011-01-01

Hoog, A., & Strzempka, K. (2011). iPhone and iOS Forensics: Investigation, Analysis and Mobile Security for Apple iPhone, iPad and iOS Devices. Waltham, MA: Syngress. 336 pages, ISBN: 978-1-59749-659-9, US$69.95.Reviewed by Christopher Schulte, EnCE & ACE, LuciData Inc., Minneapolis, Minnesota ()These are exciting times for Digital Forensics practitioners. While our examinations of mobile devices (including cell phones and tablet computers) continue to bring ne...

Parameter extraction from I-V characteristics of PV devices

Energy Technology Data Exchange (ETDEWEB)

Macabebe, Erees Queen B. [Department of Electronics, Computer and Communications Engineering, Ateneo de Manila University, Loyola Heights, Quezon City 1108 (Philippines); Department of Physics and Centre for Energy Research, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa); Sheppard, Charles J. [Department of Physics, University of Johannesburg, PO Box 524, Auckland Park 2006 (South Africa); Dyk, E. Ernest van [Department of Physics and Centre for Energy Research, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa)

2011-01-15

Device parameters such as series and shunt resistances, saturation current and diode ideality factor influence the behaviour of the current-voltage (I-V) characteristics of solar cells and photovoltaic modules. It is necessary to determine these parameters since performance parameters are derived from the I-V curve and information provided by the device parameters are useful in analyzing performance losses. This contribution presents device parameters of CuIn(Se,S){sub 2}- and Cu(In,Ga)(Se,S){sub 2}-based solar cells, as well as, CuInSe{sub 2}, mono- and multicrystalline silicon modules determined using a parameter extraction routine that employs Particle Swarm Optimization. The device parameters of the CuIn(Se,S){sub 2}- and Cu(In,Ga)(Se,S){sub 2}-based solar cells show that the contribution of recombination mechanisms exhibited by high saturation current when coupled with the effects of parasitic resistances result in lower maximum power and conversion efficiency. Device parameters of photovoltaic modules extracted from I-V characteristics obtained at higher temperature show increased saturation current. The extracted values also reflect the adverse effect of temperature on parasitic resistances. The parameters extracted from I-V curves offer an understanding of the different mechanisms involved in the operation of the devices. The parameter extraction routine utilized in this study is a useful tool in determining the device parameters which reveal the mechanisms affecting device performance. (author)

The explosion-proof container, satisfying the IAEA norms on safety

International Nuclear Information System (INIS)

Syrunin, M.A.; Fedorenko, A.G.; Ivanov, A.G.; Abakumov, A.I.; Nizovtsev, P.N.; Loginov, P.G.; Smolyakov, A.A.; Solov'ev, V.P.

1998-01-01

Safety of radioactive materials (RM) transportation is under strict control of the international norms of IAEA, aimed to ensure non-proliferation of hazardous materials in the environments. At the same time the nuclear countries use much more dangerous transportations of two types of hazardous materials. Probability of emergency explosion of high explosives (HE) during transportation and storage of such constructions is not equal to zero. HE explosion can be caused by: 1)excess of mechanical effects, allowable by the norms, on an explosive 2)lightening or fire 3)terrorist attack 4)radio controlled or time controlled mechanism in case of the terrorist device. It is obvious that an accident with explosion HE element of the nuclear weapon in an usual container, which meets the IAEA norms, but is not explosion-proof, will result in its destruction, RM dispersal, and inadmissible pollution of the environments. Therefore, it is urgent need for development of the container, which is able to withstand explosion of HE, placed in it, and to confine released RM inside of it. The experimental prototype of the load-bearing shell of the explosion-proof container (EC) can be the successfully tested spherical steel - glass plastic shell, having high-strength throats and lids. Having weight of 45-50 kg it is able to withstand internal explosion with energy more than 1.4 kg of the TNT equivalent. To preserve the explosion-proofness property in the abnormal environments during transportation, the explosion-proof container should be placed in the protective supporting transport device or the transport container (TC), consisting of the external thin-walled steel shell and the damping heat-proof layer from heat-resistant foam plastic. To justify the design parameters of such container, the tests for development and revision of the numerical model parameters were carried out. With use of this model the calculations were performed to calculate loads and the container response to 1

The incidence of pelvic fractures with traumatic lower limb amputation in modern warfare due to improvised explosive devices.

Science.gov (United States)

Cross, A M; Davis, C; Penn-Barwell, J; Taylor, D M; De Mello, W F; Matthews, J J

2014-01-01

A frequently-seen injury pattern in current military experience is traumatic lower limb amputation as a result of improvised explosive devices (IEDs). This injury can coexist with fractures involving the pelvic ring. This study aims to assess the frequency of concomitant pelvic fracture in IED-related lower limb amputation. A retrospective analysis of the trauma charts, medical notes, and digital imaging was undertaken for all patients arriving at the Emergency Department at the UK military field hospital in Camp Bastion, Afghanistan, with a traumatic lower limb amputation in the six months between September 2009 and April 2010, in order to determine the incidence of associated pelvic ring fractures. Of 77 consecutive patients with traumatic lower limb amputations, 17 (22%) had an associated pelvic fracture (eleven with displaced pelvic ring fractures, five undisplaced fractures and one acetabular fracture). Unilateral amputees (n = 31) had a 10% incidence of associated pelvic fracture, whilst 30 % of bilateral amputees (n = 46) had a concurrent pelvic fracture. However, in bilateral, trans-femoral amputations (n = 28) the incidence of pelvic fracture was 39%. The study demonstrates a high incidence of pelvic fractures in patients with traumatic lower limb amputations, supporting the routine pre-hospital application of pelvic binders in this patient group.

Emergency response guidance for the first 48 hours after the outdoors detonation of an explosive radiological dispersal device

International Nuclear Information System (INIS)

Harper, Frederick Taylor; Musolino, Stephen V.

2006-01-01

Strategies and decisions to protect emergency responders, the public, and critical infrastructure against the effects of a radiological dispersal device detonated outdoors must be made in the planning stage, not in the early period just after an attack. This contrasts with planning for small-scale types of radiological or nuclear emergencies, or for a large-scale nuclear-power-type accident that evolves over many hours or days before radioactivity is released to the environment, such that its effects can be prospectively modeled and analyzed. By the time it is known an attack has occurred, most likely there will have been casualties, all the radioactive material will have been released, plume growth will be progressing, and there will be no time left for evaluating possible countermeasures. This paper offers guidance to planners, first responders, and senior decision makers to assist them in developing strategies for protective actions and operational procedures for the first 48 hours after an explosive radiological dispersal device has been detonated

Technology of Rock Destruction by Combined Explosion-Mechanical Load

Directory of Open Access Journals (Sweden)

Oleg M. Terentiev

2017-10-01

Full Text Available Background. Rock drilling is characterized by an energy capacity of more than 120 kWh/m3. This is due to the fact that about 90 % of the energy is expended on the “preparation” of rocks for destruction. This study proposes to combine explosive and mechanical loads to reduce specific energy consumption of rock destruction. Objective. The aim of the paper is energy effective technology development for rock destruction by combined explosive-mechanical loads. Methods. Analytical studies; regression analysis; math modeling; experimental research; technical and economic analysis. Results. Specific energy decreasing for explosive-mechanical rock drilling by 4–16 % was experimentally proved. Conclusions. As a result of the implementation of explosive-mechanical rock drilling on the created full-sized experimental device, the efficiency coefficient increased from 77 to 80 %.

Explosive simulants for testing explosive detection systems

Science.gov (United States)

Kury, John W.; Anderson, Brian L.

1999-09-28

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

Bioeffects on an In Vitro Model by Small-Scale Explosives and Shock Wave Overpressure Impacts

Science.gov (United States)

2017-11-01

Many TBIs are associated with blast from improvised explosive devices.2–4 Explosions are physical, chemical , or nuclear reactions involving a rapid...ARL-TR-8210 ● NOV 2017 US Army Research Laboratory Bioeffects on an In Vitro Model by Small-Scale Explosives and Shock Wave...Research Laboratory Bioeffects on an In Vitro Model by Small-Scale Explosives and Shock Wave Overpressure Impacts by Nicole E Zander, Thuvan

Method for lowering explosives into a well and hoisting the equipment therefrom

Energy Technology Data Exchange (ETDEWEB)

Grigoryan, N G; Gushchin, N I; Fridlyander, L Ya; Vitseni, E M

1962-06-05

In order to lower the cost and simplifying the shooting and explosives procedure, the explosives and other equipment are lowered into a well on a wire line by means of their own weight. The hoisting of the shooting equipment is accomplished by means of a reactive engine attached to the device.

A Computational Investigation of Various Water-Induced Explosion Mitigation Mechanisms

Science.gov (United States)

2007-01-01

Guidelines for Evaluating the Characteristics of Vapor Cloud Explosions, Flash Fires, and BLEVEs , Center for Chemical Process Safety, AIChE, New York, NY...1994. [6]. Liebman and J. K. Richmond, Suppression of Coal Dust Explosions by Passive Water Barriers in a single Entry Mine , U.S. Bureau of Mines ...R.I. 8294, 1974. [7]. Liebman, J. Corry and J. K. Richmond, Water Barriers for Suppressing Coal Dust Explosions, U.S. Bureau of Mines R.I. 8170

Close-in airblast from underground explosions

Energy Technology Data Exchange (ETDEWEB)

Vortman, L J [Sandia Laboratories, Albuquerque, NM (United States)

1970-05-15

Air overpressures as a function of time have been measured from surface zero to about 170 ft/lb{sup 1/3} along the ground from nuclear and chemical explosions. Charge depths varied from the surface to depths below which explosion gases are contained. A ground-shock-induced air pressure pulse is clearly distinguishable from the pulse caused by venting gases. Measured peak overpressures show reasonable agreement with the theoretical treatment by Monta. In a given medium the suppression of blast with explosion burial depth is a function of the relative distance at which the blast is observed. Rates of suppression of peak overpressure with charge burial are different for the two pulses. Rates are determined for each pulse over the range of distances at which measurements have been made of air overpressure from chemical explosions in several media. Nuclear data are available from too few shots for similar dependence on burial depth and distance to be developed, but it is clear that the gas venting peak overpressure from nuclear explosions is much more dependent on medium than that from chemical explosions. For above-ground explosions, experiment has shown that airblast from a I-kiloton nuclear explosion is equal to that from a 0.5-kiloton TNT explosion. Data on ground-shock-induced airblast is now sufficient to show that a similar relationship may exist for buried explosions. Because of medium dependence of the gas venting pulse from nuclear explosions, data from additional nuclear events will be required before a chemical/nuclear airblast equivalence can be determined for the gas-venting pulse. (author)

Effects of GeI2 or ZnI2 addition to perovskite CH3NH3PbI3 photovoltaic devices

Science.gov (United States)

Tanaka, Hiroki; Ohishi, Yuya; Oku, Takeo

2018-01-01

CH3NH3PbI3 added with GeI2 or ZnI2 perovskite photovoltaic devices were fabricated characterized. The surface coverages of the perovskite layers were improved by the addition of GeI2 or ZnI2. Formation of PbI2 observed for the pristine CH3NH3PbI3 was suppressed by the GeI2 or ZnI2 addition, which resulted in the improvement of the conversion efficiencies of the perovskite photovoltaic devices.

Explosive Characteristics of Carbonaceous Nanoparticles

Science.gov (United States)

Turkevich, Leonid; Fernback, Joseph; Dastidar, Ashok

2013-03-01

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

Forensic analysis of social networking application on iOS devices

Science.gov (United States)

Zhang, Shuhui; Wang, Lianhai

2013-12-01

The increased use of social networking application on iPhone and iPad make these devices a goldmine for forensic investigators. Besides, QQ, Wechat, Sina Weibo and skype applications are very popular in China and didn't draw attention to researchers. These social networking applications are used not only on computers, but also mobile phones and tablets. This paper focuses on conducting forensic analysis on these four social networking applications on iPhone and iPad devices. The tests consisted of installing the social networking applications on each device, conducting common user activities through each application and correlation analysis with other activities. Advices to the forensic investigators are also given. It could help the investigators to describe the crime behavior and reconstruct the crime venue.

Railguns powered by explosive driven flux compression generators

International Nuclear Information System (INIS)

Fowler, C.M.; Zimmermann, E.L.; Cummings, C.E.

1986-01-01

Explosive driven flux compression generators (FCG's) are single-shot devices that convert part of the energy of high explosives into electromagnetic energy. Some classes of these generators have served quite well as railgun power sources. In this paper and the following paper we describe strip and helical type FCG's, both of which are in use in the Los Alamos railgun program. Advantages and disadvantages these generators have for railgun power supplies will be discussed, together with experimental results obtained and some of the diagnostics we have found particularly useful

Polymer nanocomposite nanomechanical cantilever sensors: material characterization, device development and application in explosive vapour detection

International Nuclear Information System (INIS)

Seena, V; Fernandes, Avil; Ramgopal Rao, V; Pant, Prita; Mukherji, Soumyo

2011-01-01

This paper reports an optimized and highly sensitive piezoresistive SU-8 nanocomposite microcantilever sensor and its application for detection of explosives in vapour phase. The optimization has been in improving its electrical, mechanical and transduction characteristics. We have achieved a better dispersion of carbon black (CB) in the SU-8/CB nanocomposite piezoresistor and arrived at an optimal range of 8-9 vol% CB concentration by performing a systematic mechanical and electrical characterization of polymer nanocomposites. Mechanical characterization of SU-8/CB nanocomposite thin films was performed using the nanoindentation technique with an appropriate substrate effect analysis. Piezoresistive microcantilevers having an optimum carbon black concentration were fabricated using a design aimed at surface stress measurements with reduced fabrication process complexity. The optimal range of 8-9 vol% CB concentration has resulted in an improved sensitivity, low device variability and low noise level. The resonant frequency and spring constant of the microcantilever were found to be 22 kHz and 0.4 N m -1 respectively. The devices exhibited a surface stress sensitivity of 7.6 ppm (mN m -1 ) -1 and the noise characterization results support their suitability for biochemical sensing applications. This paper also reports the ability of the sensor in detecting TNT vapour concentration down to less than six parts per billion with a sensitivity of 1 mV/ppb.

Polymer nanocomposite nanomechanical cantilever sensors: material characterization, device development and application in explosive vapour detection

Energy Technology Data Exchange (ETDEWEB)

Seena, V; Fernandes, Avil; Ramgopal Rao, V [Centre for Excellence in Nanoelectronics, Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra (India); Pant, Prita [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai, Maharashtra (India); Mukherji, Soumyo, E-mail: seenapradeep@iitb.ac.in, E-mail: rrao@ee.iitb.ac.in [Department of Biosciences and Bio-engineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra (India)

2011-07-22

This paper reports an optimized and highly sensitive piezoresistive SU-8 nanocomposite microcantilever sensor and its application for detection of explosives in vapour phase. The optimization has been in improving its electrical, mechanical and transduction characteristics. We have achieved a better dispersion of carbon black (CB) in the SU-8/CB nanocomposite piezoresistor and arrived at an optimal range of 8-9 vol% CB concentration by performing a systematic mechanical and electrical characterization of polymer nanocomposites. Mechanical characterization of SU-8/CB nanocomposite thin films was performed using the nanoindentation technique with an appropriate substrate effect analysis. Piezoresistive microcantilevers having an optimum carbon black concentration were fabricated using a design aimed at surface stress measurements with reduced fabrication process complexity. The optimal range of 8-9 vol% CB concentration has resulted in an improved sensitivity, low device variability and low noise level. The resonant frequency and spring constant of the microcantilever were found to be 22 kHz and 0.4 N m{sup -1} respectively. The devices exhibited a surface stress sensitivity of 7.6 ppm (mN m{sup -1}){sup -1} and the noise characterization results support their suitability for biochemical sensing applications. This paper also reports the ability of the sensor in detecting TNT vapour concentration down to less than six parts per billion with a sensitivity of 1 mV/ppb.

Polymer nanocomposite nanomechanical cantilever sensors: material characterization, device development and application in explosive vapour detection.

Science.gov (United States)

Seena, V; Fernandes, Avil; Pant, Prita; Mukherji, Soumyo; Rao, V Ramgopal

2011-07-22

This paper reports an optimized and highly sensitive piezoresistive SU-8 nanocomposite microcantilever sensor and its application for detection of explosives in vapour phase. The optimization has been in improving its electrical, mechanical and transduction characteristics. We have achieved a better dispersion of carbon black (CB) in the SU-8/CB nanocomposite piezoresistor and arrived at an optimal range of 8-9 vol% CB concentration by performing a systematic mechanical and electrical characterization of polymer nanocomposites. Mechanical characterization of SU-8/CB nanocomposite thin films was performed using the nanoindentation technique with an appropriate substrate effect analysis. Piezoresistive microcantilevers having an optimum carbon black concentration were fabricated using a design aimed at surface stress measurements with reduced fabrication process complexity. The optimal range of 8-9 vol% CB concentration has resulted in an improved sensitivity, low device variability and low noise level. The resonant frequency and spring constant of the microcantilever were found to be 22 kHz and 0.4 N m(-1) respectively. The devices exhibited a surface stress sensitivity of 7.6 ppm (mN m(-1))(-1) and the noise characterization results support their suitability for biochemical sensing applications. This paper also reports the ability of the sensor in detecting TNT vapour concentration down to less than six parts per billion with a sensitivity of 1 mV/ppb.

EVENT, Explosive Transients in Flow Networks

International Nuclear Information System (INIS)

Andrae, R.W.; Tang, P.K.; Bolstad, J.W.; Gregory, W.S.

1985-01-01

1 - Description of problem or function: A major concern of the chemical, nuclear, and mining industries is the occurrence of an explosion in one part of a facility and subsequent transmission of explosive effects through the ventilation system. An explosive event can cause performance degradation of the ventilation system or even structural failures. A more serious consequence is the release of hazardous materials to the environment if vital protective devices such as air filters, are damaged. EVENT was developed to investigate the effects of explosive transients through fluid-flow networks. Using the principles of fluid mechanics and thermodynamics, governing equations for the conservation of mass, energy, and momentum are formulated. These equations are applied to the complete network subdivided into two general components: nodes and branches. The nodes represent boundaries and internal junctions where the conservation of mass and energy applies. The branches can be ducts, valves, blowers, or filters. Since in EVENT the effect of the explosion, not the characteristics of the explosion itself, is of interest, the transient is simulated in the simplest possible way. A rapid addition of mass and energy to the system at certain locations is used. This representation is adequate for all of the network except the region where the explosion actually occurs. EVENT84 is a modification of EVENT which includes a new explosion chamber model subroutine based on the NOL BLAST program developed at the Naval Ordnance Laboratory, Silver Spring, Maryland. This subroutine calculates the confined explosion near-field parameters and supplies the time functions of energy and mass injection. Solid-phase or TNT-equivalent explosions (which simulate 'point source' explosions in nuclear facilities) as well as explosions in gas-air mixtures can be simulated. The four types of explosions EVENT84 simulates are TNT, hydrogen in air, acetylene in air, and tributyl phosphate (TBP or 'red oil

PINS Testing and Modification for Explosive Identification

International Nuclear Information System (INIS)

Seabury, E.H.; Caffrey, A.J.

2011-01-01

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.

Surface motion induced by nuclear explosions beneath Pahute Mesa. Part I. Halfbreak, Greeley, Scotch, Boxcar events

International Nuclear Information System (INIS)

Perret, W.R.

1976-10-01

Results of surface motion studies conducted by Sandia Laboratories during seven underground nuclear explosions detonated beneath Pahute Mesa, Areas 19 and 20 of the Nevada Test Site, between 1966 and 1973 are reported. The report is divided into two parts of which this, Part I, includes (1) descriptions of the Pahute Mesa geological environment and of the purposes and instrumentation used in these programs (Chapter 1), and (2) description of four events, the data derived from each, and analysis of these data. These Part I events are HALFBEAK (Chapter 2), GREELEY (Chapter 3), SCOTCH (Chapter 4), and BOXCAR (Chapter 5) for all of which a nominally radial array of gage stations yielded data as a function of distance primarily, although in a few cases data were derived from stations at widely separated azimuths from the explosion. Results of the analysis indicate that average propagation velocity through the geologic column between the explosions and mesa surface was about 8800 ft/sec and that for horizontal distances greater than shot depth, refraction occurred within rhyolite flows with characteristic velocity of about 12,300 ft/sec. There is evidence which suggests possible deeper refraction at a velocity between 18,000 and 21,000 ft/sec. Only the verticle motion peaks follow a pattern amenable to regression analysis because geometrical effects influence horizontal motion amplitudes differently as horizontal distances increase. Particle velocities vary roughly as the inverse square of slant or radial range with exponent values ranging from -3.9 to -1.3. Displacements follow a similar pattern with exponents ranging from about -6 to -2. Displacement profiles at various times during the motion and displacement hodographs in the vertical-radial plane aid in understanding several local phenomena implied by individual motion records

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.

Explosion-proof actuators according to EU directive 94/9/EC (ATEX)

Energy Technology Data Exchange (ETDEWEB)

Herbstritt, M. [AUMA Riester GmbH und Co. KG. Muellheim (Germany)

2004-07-01

Since July, 1, 2003 only explosion-proof devices which conform to the new EU Directive 94/9/EC, better known as the ATEX Directive, are introduced to the market. Especially the explosion protection of non-electrical equipment is a completely new task for many manufacturers. AUMA has qualified its electric actuators for the automation of industrial valves in accordance with the new regulations. In addition the design has been improved. (orig.)

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

Directory of Open Access Journals (Sweden)

Qingjie Jiao

2018-03-01

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

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

Science.gov (United States)

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

2018-03-01

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

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

Science.gov (United States)

2013-10-28

..., including non-cap sensitive slurry and water gel explosives. Blasting caps. Blasting gelatin. Blasting.... Explosive conitrates. Explosive gelatins. Explosive liquids. Explosive mixtures containing oxygen-releasing... powder. [[Page 64247

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

OpenAIRE

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

2018-01-01

To control the explosion energy output by optimizing explosive components is a key requirement in a number of different application areas. The effect of different Al/O Ratio on underwater explosion of aluminized explosives has been studied detailedly. However, the effect of explosive percentage in the same Al/O Ratio is rarely researched, especially for Hexanitrohexaazaisowurtzitane (CL-20) based aluminized explosives. In this study, we performed the underwater explosion experiments with 1.2-...

Book Review: iPhone and iOS Forensics: Investigation, Analysis and Mobile Security for Apple iPhone, iPad and iOS Devices

Directory of Open Access Journals (Sweden)

Schulte Christopher

2011-12-01

Full Text Available Hoog, A., & Strzempka, K. (2011. iPhone and iOS Forensics: Investigation, Analysis and Mobile Security for Apple iPhone, iPad and iOS Devices. Waltham, MA: Syngress. 336 pages, ISBN: 978-1-59749-659-9, US$69.95.Reviewed by Christopher Schulte, EnCE & ACE, LuciData Inc., Minneapolis, Minnesota (cschulte@lucidatainc.comThese are exciting times for Digital Forensics practitioners. While our examinations of mobile devices (including cell phones and tablet computers continue to bring new and sometimes hair-pulling challenges into our labs and on-site engagements, research and understanding of these tiny computers is increasing at what seems an exponential rate. This is especially true in the iOS (Apple Computer’s mobile operating system that powers the iPhone, iPad, iPod Touch and Apple TV space. The diligent work of talented computer scientists in this field allows examiners everywhere to reap the benefits of easier, faster and more effective examinations that yield more accurate and defendable results.(see PDF for full review

Development of graphene nanoplatelet embedded polymer microcantilever for vapour phase explosive detection applications

International Nuclear Information System (INIS)

Ray, Prasenjit; Pandey, Swapnil; Ramgopal Rao, V.

2014-01-01

In this work, a graphene based strain sensor has been reported for explosive vapour detection applications by exploiting the piezoresistive property of graphene. Instead of silicon based cantilevers, a low cost polymeric micro-cantilever platform has been used to fabricate this strain sensor by embedding the graphene nanoplatelet layer inside the beam. The fabricated devices were characterized for their mechanical and electromechanical behaviour. This device shows a very high gauge factor which is around ∼144. Also the resonant frequency of these cantilevers is high enough such that the measurements are not affected by environmental noise. These devices have been used in this work for reliable detection of explosive vapours such as 2,4,6-Trinitrotoluene down to parts-per-billion concentrations in ambient conditions.

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.

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

International Nuclear Information System (INIS)

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

2016-01-01

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

iPosture: The Size of Electronic Consumer Devices Affects our Behavior

OpenAIRE

Bos, Maarten W.; Cuddy, Amy J. C.

2013-01-01

We examined whether incidental body posture, prompted by working on electronic devices of different sizes, affects power-related behaviors. Grounded in research showing that adopting expansive body postures increases psychological power, we hypothesized that working on larger devices, which forces people to physically expand, causes users to behave more assertively. Participants were randomly assigned to interact with one of four electronic devices that varied in size: an iPod Touch, an iPad,...

Nano-Evaluris: an inhalation and explosion risk evaluation method for nanoparticle use. Part I: description of the methodology

Science.gov (United States)

Bouillard, Jacques X.; Vignes, Alexis

2014-02-01

In this paper, an inhalation health and explosion safety risk assessment methodology for nanopowders is described. Since toxicological threshold limit values are still unknown for nanosized substances, detailed risk assessment on specific plants may not be carried out. A simple approach based on occupational hazard/exposure band expressed in mass concentrations is proposed for nanopowders. This approach is consolidated with an iso surface toxicological scaling method, which has the merit, although incomplete, to provide concentration threshold levels for which new metrological instruments should be developed for proper air monitoring in order to ensure safety. Whenever the processing or use of nanomaterials is introducing a risk to the worker, a specific nano pictogram is proposed to inform the worker. Examples of risk assessment of process equipment (i.e., containment valves) processing various nanomaterials are provided. Explosion risks related to very reactive nanomaterials such as aluminum nanopowders can be assessed using this new analysis methodology adapted to nanopowders. It is nevertheless found that to formalize and extend this approach, it is absolutely necessary to develop new relevant standard apparatuses and to qualify individual and collective safety barriers with respect to health and explosion risks. In spite of these uncertainties, it appears, as shown in the second paper (Part II) that health and explosion risks, evaluated for given MWCNTs and aluminum nanoparticles, remain manageable in their continuous fabrication mode, considering current individual and collective safety barriers that can be put in place. The authors would, however, underline that peculiar attention must be paid to non-continuous modes of operations, such as process equipment cleaning steps, that are often under-analyzed and are too often forgotten critical steps needing vigilance in order to minimize potential toxic and explosion risks.

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.

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.

Assessment of Safety Parameters for Radiological Explosion Based on Gaussian Dispersion Model

Energy Technology Data Exchange (ETDEWEB)

Pandey, Alok [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Yu, Hyungjoon; Kim, Hong Suk [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

2014-10-15

These sources if used with explosive (called RDD - radiological dispersion device), can cause dispersion of radioactive material resulting in public exposure and contamination of the environment. Radiological explosion devices are not weapons for the mass destruction like atom bombs, but can cause the death of few persons and contamination of large areas. The reduction of the threat of radiological weapon attack by terrorist groups causing dispersion of radioactive material is one of the priority tasks of the IAEA Nuclear Safety and Security Program.Emergency preparedness is an essential part for reducing and mitigating radiological weapon threat. Preliminary assessment of dispersion study followed by radiological explosion and its quantitative effect will be helpful for the emergency preparedness team for an early response. The effect of the radiological dispersion depends on various factors like radioisotope, its activity, physical form, amount of explosive used and meteorological factors at the time of an explosion. This study aim to determine the area affected by the radiological explosion as pre assessment to provide feedback to emergency management teams for handling and mitigation the situation after an explosion. Most practical scenarios of radiological explosion are considered with conservative approach for the assessment of the area under a threat for emergency handling and management purpose. Radioisotopes under weak security controls can be used for a radiological explosion to create terror and socioeconomic threat for the public. Prior assessment of radiological threats is helpful for emergency management teams to take prompt decision about evacuation of the affected area and other emergency handling actions. Comparable activities of Co-60 source used in radiotherapy and Sr-90 source of disused and orphaned RTGs with two different quantities of TNT were used for the scenario development of radiological explosion. In the Basic Safety Standard (BSS

Assessment of Safety Parameters for Radiological Explosion Based on Gaussian Dispersion Model

International Nuclear Information System (INIS)

Pandey, Alok; Yu, Hyungjoon; Kim, Hong Suk

2014-01-01

These sources if used with explosive (called RDD - radiological dispersion device), can cause dispersion of radioactive material resulting in public exposure and contamination of the environment. Radiological explosion devices are not weapons for the mass destruction like atom bombs, but can cause the death of few persons and contamination of large areas. The reduction of the threat of radiological weapon attack by terrorist groups causing dispersion of radioactive material is one of the priority tasks of the IAEA Nuclear Safety and Security Program.Emergency preparedness is an essential part for reducing and mitigating radiological weapon threat. Preliminary assessment of dispersion study followed by radiological explosion and its quantitative effect will be helpful for the emergency preparedness team for an early response. The effect of the radiological dispersion depends on various factors like radioisotope, its activity, physical form, amount of explosive used and meteorological factors at the time of an explosion. This study aim to determine the area affected by the radiological explosion as pre assessment to provide feedback to emergency management teams for handling and mitigation the situation after an explosion. Most practical scenarios of radiological explosion are considered with conservative approach for the assessment of the area under a threat for emergency handling and management purpose. Radioisotopes under weak security controls can be used for a radiological explosion to create terror and socioeconomic threat for the public. Prior assessment of radiological threats is helpful for emergency management teams to take prompt decision about evacuation of the affected area and other emergency handling actions. Comparable activities of Co-60 source used in radiotherapy and Sr-90 source of disused and orphaned RTGs with two different quantities of TNT were used for the scenario development of radiological explosion. In the Basic Safety Standard (BSS

21 CFR 822.28 - If I stop marketing the device subject to postmarket surveillance, what must I do?

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false If I stop marketing the device subject to postmarket surveillance, what must I do? 822.28 Section 822.28 Food and Drugs FOOD AND DRUG ADMINISTRATION... of Manufacturers § 822.28 If I stop marketing the device subject to postmarket surveillance, what...

Control solutions for robots using Android and iOS devices

Science.gov (United States)

Evans, A. William, III; Gray, Jeremy P.; Rudnick, Dave; Karlsen, Robert E.

2012-06-01

As more Soldiers seek to utilize robots to enhance their mission capabilities, controls are needed which are intuitive, portable, and adaptable to a wide range of mission tasks. Android™ and iOS™ devices have the potential to meet each of these requirements as well as being based on readily available hardware. This paper will focus on some of the ways in which an Android™ or iOS™ device could be used to control specific and varied robot mobility functions and payload tools. Several small unmanned ground vehicle (SUGV) payload tools will have been investigated at Camp Pendleton during a user assessment and mission feasibility study for automatic remote tool changing. This group of payload tools will provide a basis, to researchers, concerning what types of control functions are needed to fully utilize SUGV robotic capabilities. Additional, mobility functions using tablet devices have been used as part of the Safe Operation of Unmanned systems for Reconnaissance in Complex Environments Army Technology Objective (SOURCE ATO) which is investigating the safe operation of robotics. Using Android™ and iOS™ hand-held devices is not a new concept in robot manipulation. However, the authors of this paper hope to introduce some novel concepts that may serve to make the interaction between Soldier and machine more fluid and intuitive. By creating a better user experience, Android™ and iOS™ devices could help to reduce training time, enhance performance, and increase acceptance of robotics as valuable mission tools for Soldiers.

Finite element investigation of explosively formed projectiles (EFP)

International Nuclear Information System (INIS)

Ahmad, I.

1999-01-01

This thesis report represents the numerical simulation of explosively formed projectiles (EFP), a type of linear self-forging fragment device. The simulation is performed using a finite element code DYNA2D. It also explicates that how the shape, velocity and kinetic energy of an explosively formed projectile is effected by various parameters. Different parameters investigated are mesh density, material, thickness, contour and types of liner. Effect of shape of casing and material model is also analyzed. The shapes of projectiles at different times after detonation are shown. The maximum velocity and kinetic energy of the projectile have been used to ascertain the effect of above mentioned parameters. (author)

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

Energy Technology Data Exchange (ETDEWEB)

Gierlik, M., E-mail: m.gierlik@ncbj.gov.pl; Borsuk, S.; Guzik, Z.; Iwanowska, J.; Kaźmierczak, Ł.; Korolczuk, S.; Kozłowski, T.; Krakowski, T.; Marcinkowski, R.; Swiderski, L.; Szeptycka, M.; Szewiński, J.; Urban, A.

2016-10-21

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

Degassing Processes at Persistently Active Explosive Volcanoes

Science.gov (United States)

Smekens, Jean-Francois

Among volcanic gases, sulfur dioxide (SO2) is by far the most commonly measured. More than a monitoring proxy for volcanic degassing, SO 2 has the potential to alter climate patterns. Persistently active explosive volcanoes are characterized by short explosive bursts, which often occur at periodic intervals numerous times per day, spanning years to decades. SO 2 emissions at those volcanoes are poorly constrained, in large part because the current satellite monitoring techniques are unable to detect or quantify plumes of low concentration in the troposphere. Eruption plumes also often show high concentrations of ash and/or aerosols, which further inhibit the detection methods. In this work I focus on quantifying volcanic gas emissions at persistently active explosive volcanoes and their variations over short timescales (minutes to hours), in order to document their contribution to natural SO2 flux as well as investigate the physical processes that control their behavior. In order to make these measurements, I first develop and assemble a UV ground-based instrument, and validate it against an independently measured source of SO2 at a coal-burning power plant in Arizona. I establish a measurement protocol and demonstrate that the instrument measures SO 2 fluxes with Indonesia), a volcano that has been producing cycles of repeated explosions with periods of minutes to hours for the past several decades. Semeru produces an average of 21-71 tons of SO2 per day, amounting to a yearly output of 8-26 Mt. Using the Semeru data, along with a 1-D transient numerical model of magma ascent, I test the validity of a model in which a viscous plug at the top of the conduit produces cycles of eruption and gas release. I find that it can be a valid hypothesis to explain the observed patterns of degassing at Semeru. Periodic behavior in such a system occurs for a very narrow range of conditions, for which the mass balance between magma flux and open-system gas escape repeatedly

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.

iPhone and iOS Forensics Investigation, Analysis and Mobile Security for Apple iPhone, iPad and iOS Devices

CERN Document Server

Hoog, Andrew

2011-01-01

As sales and usage of iPhones increase so does the demand on organizations that conduct examinations on this device. iPhone and iOS Forensics takes an in-depth look at methods and processes that analyze the iPhone/iPod in an official legal manner. All of the methods and procedures outlined in the book can be taken into any court room. This book details the iPhone with information data sets that are new and evolving, with official hardware knowledge from Apple itself to help aid investigators.  iPhone market share has increased to 50% of worldwide mobile phone usageEmployment in digital fo

Conversion of chemical energy in an explosive by a magnetohydrodynamic method

International Nuclear Information System (INIS)

Lebedev, E.F.; Ostashev, V.E.; Svetsov, G.A.

1983-01-01

In this paper, the authors examine different methods for realizing the MHD method for converting chemical energy of a condensed explosive into pulsed electrical energy. It is shown that explosive MHD generators, which are compact sources of powerful pulses of electrical energy, are characterized by their relative simplicity, autonomy and maneuverability of firing and they are capable of operating in the frequency-periodic mode. A number of projects have been proposed for explosive MHD generators in the megajoule range. Practical experience has been gained in creating frequency-periodic action generators as well as autonomous setups using superconducting magnetic systems. The increase in the operational efficiency of an explosive MHD generator is primarily related to increasing the magnetic Reynolds number of the flow, which can be attained, in particular, by using different schemes for accumulating the energy of the explosion. The use of a metallic liner, which expands under the pressure of the detonation products, in an explosive MHD generator is, in the practical sense, apparently hopeless. The general information available on the parameters and properties of explosive MHD generators gives a basis for concluding that this generator is a promising source of powerful energy pulses. In a certain range of parameters, it can be an alternative to the use of conventional high-energy pulse devices

Vapour cloud explosion hazard greater with light feedstocks

Energy Technology Data Exchange (ETDEWEB)

Windebank, C.S.

1980-03-03

Because lighter chemical feedstocks such as propylene and butylenes are more reactive than LPG's they pose a greater risk of vapor cloud explosion, particularly during their transport. According to C.S. Windebank (Insurance Tech. Bur.), percussive unconfined vapor cloud explosions (PUVCE's) do not usually occur below the ten-ton threshold for saturated hydrocarbons but can occur well below this threshold in the case of unsaturated hydrocarbons such as propylene and butylenes. Boiling liquid expanding vapor explosions (BLEVE's) are more likely to be ''hot'' (i.e., the original explosion is associated with fire) than ''cold'' in the case of unsaturated hydrocarbons. No PUVCE or BLEVE incident has been reported in the UK. In the US, 16 out of 20 incidents recorded between 1970 and 1975 were related to chemical feedstocks, including propylene and butylenes, and only 4 were LPG-related. The average losses were $20 million per explosion. Between 1968 and 1978, 8% of LPG pipeline spillages led to explosions.

Increasing the selectivity and sensitivity of gas sensors for the detection of explosives

Science.gov (United States)

Mallin, Daniel

Over the past decade, the use of improvised explosive devices (IEDs) has increased, domestically and internationally, highlighting a growing need for a method to quickly and reliably detect explosive devices in both military and civilian environments before the explosive can cause damage. Conventional techniques have been successful in explosive detection, however they typically suffer from enormous costs in capital equipment and maintenance, costs in energy consumption, sampling, operational related expenses, and lack of continuous and real-time monitoring. The goal was thus to produce an inexpensive, portable sensor that continuously monitors the environment, quickly detects the presence of explosive compounds and alerts the user. In 2012, here at URI, a sensor design was proposed for the detection of triacetone triperoxide (TATP). The design entailed a thermodynamic gas sensor that measures the heat of decomposition between trace TATP vapor and a metal oxide catalyst film. The sensor was able to detect TATP vapor at the part per million level (ppm) and showed great promise for eventual commercial use, however, the sensor lacked selectivity. Thus, the specific objective of this work was to take the original sensor design proposed in 2012 and to make several key improvements to advance the sensor towards commercialization. It was demonstrated that a sensor can be engineered to detect TATP and ignore the effects of interferent H2O2 molecules by doping SnO2 films with varying amounts of Pd. Compared with a pure SnO2 catalyst, a SnO2, film doped with 8 wt. % Pd had the highest selectivity between TATP and H2O2. Also, at 12 wt. % Pd, the response to TATP and H2O2 was enhanced, indicating that sensitivity, not only selectivity, can be increased by modifying the composition of the catalyst. An orthogonal detection system was demonstrated. The platform consists of two independent sensing mechanisms, one thermodynamic and one conductometric, which take measurements from

Simulation of steam explosion in stratified melt-coolant configuration

International Nuclear Information System (INIS)

Leskovar, Matjaž; Centrih, Vasilij; Uršič, Mitja

2016-01-01

Highlights: • Strong steam explosions may develop spontaneously in stratified configurations. • Considerable melt-coolant premixed layer formed in subcooled water with hot melts. • Analysis with MC3D code provided insight into stratified steam explosion phenomenon. • Up to 25% of poured melt was mixed with water and available for steam explosion. • Better instrumented experiments needed to determine dominant mixing process. - Abstract: A steam explosion is an energetic fuel coolant interaction process, which may occur during a severe reactor accident when the molten core comes into contact with the coolant water. In nuclear reactor safety analyses steam explosions are primarily considered in melt jet-coolant pool configurations where sufficiently deep coolant pool conditions provide complete jet breakup and efficient premixture formation. Stratified melt-coolant configurations, i.e. a molten melt layer below a coolant layer, were up to now believed as being unable to generate strong explosive interactions. Based on the hypothesis that there are no interfacial instabilities in a stratified configuration it was assumed that the amount of melt in the premixture is insufficient to produce strong explosions. However, the recently performed experiments in the PULiMS and SES (KTH, Sweden) facilities with oxidic corium simulants revealed that strong steam explosions may develop spontaneously also in stratified melt-coolant configurations, where with high temperature melts and subcooled water conditions a considerable melt-coolant premixed layer is formed. In the article, the performed study of steam explosions in a stratified melt-coolant configuration in PULiMS like conditions is presented. The goal of this analytical work is to supplement the experimental activities within the PULiMS research program by addressing the key questions, especially regarding the explosivity of the formed premixed layer and the mechanisms responsible for the melt-water mixing. To

U.S. nuclear exotica: Peaceful use of nuclear explosives

International Nuclear Information System (INIS)

Sylves, R.T.

1986-01-01

Project Plowshare, the U.S. Atomic Energy Commission (AEC) program to investigate possible non-military uses for nuclear explosives, was an offshoot of President Eisenhower's ''Atoms for Peace'' proposal. Plowshare was, in a sense, two separate programs. One was for nuclear excavation projects applied to grand-scale civil engineering ventures. Much of what had sustained nuclear excavation Plowshare in the 1960s was the hope and belief that this new instrument of civil engineering would prove its value in construction of a second great Pan-American canal. The other was for contained underground blasting to serve parties interested in mining, underground natural gas storage, and long-term disposal of toxic and radioactive materials. Both programs were intertwined with military and national security-related experiments. Given the heavy security which justifiably surrounded AEC use of thermonuclear devices, and fears of nuclear terrorism as well as nuclear proliferation concerns, even Plowshare's most ardent supporters never expected the project to hand private industry a thermonuclear explosive device

Ground deposition pattern of an explosive radiological dispersal device (RDD)

International Nuclear Information System (INIS)

Sharon, A.; Halevy, I.; Sattinger, D.; Berenstein, Z.; Neuman, R.; Banaim, P.; Pinhas, M.; Yaar, I.

2014-01-01

Activity deposition pattern of outdoor explosive RDD experiments were discussed and analyzed. In cases of fine, respirable size, aerosols dispersion, most of the activity deposited inside a circle of up to 4 fireball radii around the detonation point. About an order of magnitude less was deposited in the rest of the wide open area, in the downwind direction. The effects of different RA particles size distribution on the ground deposition pattern is still being studying under the framework of GF project

Explosive device of conduit using Ti Ni alloy

Directory of Open Access Journals (Sweden)

A. Yu. Kolobov

2014-01-01

Full Text Available Presently, materials have been developed which are capable at changing temperate to return significant inelastic deformations, exhibit rubber-like elasticity, convert heat into mechanical work, etc. The aggregate of these effects is usually called the shape memory effect.At present a great number of compounds and alloys with a shape memory effect has been known.These are alloys based on titanium nickelide (TiNi, copper-based alloys (Cu-Al, Cu-Sn, Cu-Al-Ni, Cu-Zn-Si, etc., gold and silver (Ag-Cd, Au-Ag-Cd, Au-Cd-Cu, Au-Zn-Cu, etc., manganese (Mn-Cr, Fe-Cu, Mn-Cu-Ni, Mn-Cu-Zr, Mn-Ni, etc., iron (Fe-Mn, Fe-Ni, Fe-Al, etc., and other compounds.The alloys based on titanium nickelide (nitinol are the most widely used.Alloys with shape memory effect find various applications in engineering and medicine, namely connecting devices, actuators, transformable design, multipurpose medical implants, etc.There is a task of breaking fuel conduit during separating the spacecraft from the rocket in space technology.The paper examines the procedure for design calculation of the separating device of conduit with the use of Ti-Ni alloy. This device can be used instead of the pyro-knives.The device contains two semi-rings from Ti-Ni alloy. In the place of break on the conduit an annular radius groove is made.At a temperature of martensite passage the semi-rings undergo deformation and in the strained state are set in the device. With heating to the temperature of the austenitic passage of bushing macro-deformation the energy stored by the nitinol bushing is great enough to break the conduit on the neck.The procedures of design calculation and response time of device are given.

Explosive strength training improves speed and agility in wheelchair basketball athletes

OpenAIRE

Tarik Ozmen; Bekir Yuktasir; Necmiye Un Yildirim; Birol Yalcin; Mark ET Willems

2014-01-01

INTRODUCTION: Wheelchair basketball is a paralympic sport characterized by intermittent high-intensity activities that require explosive strength and speed. OBJECTIVE: To investigate the effect of explosive strength training on speed and agility performance in wheelchair basketball players. METHODS: Ten male wheelchair basketball players (Mage=31±4 yrs) were divided into two groups [i.e. explosive strength training (ES); control (CN)] based on International Wheelchair Basketball Fede...

Study on explosion field temperature testing system based on wireless data transmission

International Nuclear Information System (INIS)

Wang Xinling; Sun Yunqiang

2011-01-01

The accurate measurement of the transient temperature value produced by explosive blasting may provide the basis for distinguishing the types of the explosive, the power contrast of the explosive and the performance evaluation in the weapons research process. To solve the problems of the Universal Test System emplaced inconveniently and the stored testing system need to be recycled, it has designed the explosion field application in wireless sensor system of temperature measurement. The system based on PIC16F877A micro controller, CPLD complex programmable logic devices and nRF24L01 wireless transmission chip sensor. The system adopts the Tungsten-Rhenium Thermocouple as the temperature sensor, DS600 temperature sensor for cold temperature compensation. This system has arrangement convenient, high-speed data acquisition, trigger and working parameters of adjustable characteristics, has been successfully applied in a test system. (authors)

Frictional properties of single crystals HMX, RDX and PETN explosives

International Nuclear Information System (INIS)

Wu, Y.Q.; Huang, F.L.

2010-01-01

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

Explosive processes in nucleosynthesis

International Nuclear Information System (INIS)

Boyd, R.N.

2002-01-01

There are many explosive processes in nucleosynthesis: big bang nucleosynthesis, the rp-process, the γ-process, the ν-process, and the r-process. However, I will discuss just the rp-process and the r-process in detail, primarily because both seem to have been very active research areas of late, and because they have great potential for studies with radioactive nuclear beams. I will also discuss briefly the γ-process because of its inevitability in conjunction with the rp-process. (orig.)

A seismic recording device

Energy Technology Data Exchange (ETDEWEB)

Dixon, R; Kind, A G; Thompson, S R

1983-06-08

A method and a device for noting the moment of an explosion on a seismic recording is proposed, in which the moment of the explosion is recorded as a result of a break in an electrical circuit under the effects of the explosive charge used to excite the seismic waves. The electrical circuit being broken is connected to the same energy source as the electric detonator which initiates the explosion, which is attached to a high frequency, alternating current source, where the circuit being broken is either the primary or the secondary winding of a transformer, through which the electric detonator is switched in to the source. The moment the circuit is broken is determined from the ceasation of current in the circuit or by the sharp rise in voltage in the broken sector. The method makes it possible to more precisely fix the moment of the break than the existing methods. When insulated copper wires are used the recording of the time occurs 100 microseconds after the explosion.

Influence of external-detonation-generated plasmas on the performance of semi-confined explosive charges

Energy Technology Data Exchange (ETDEWEB)

Udy, L.L.

1979-02-01

External-detonation-generated plasmas, highly ionized zones of reacting material ejected from the surface of detonating explosive charges, are shown to be the cause of channel desensitization, i.e., the self-quenching of a detonating explosive column loaded in a borehole with an air annulus between the explosive and the borehole wall. The effects of this phenomenon on several explosive compositions and types are demonstrated and discussed. The explosives tested include aluminum-sensitized and explosive-sensitized slurries, ANFO, liquid explosives and dynamites. Various techniques are described that can be used to reduce or eliminate the plasma effect.

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

International Nuclear Information System (INIS)

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

2001-01-01

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

MEMS-based Porous Silicon Preconcentrators Filled with Carbopack-B for Explosives Detection

OpenAIRE

Camara , El Hadji Malik; James , Franck; Breuil , Philippe; Pijolat , Christophe; Briand , Danick; De Rooij , Nicolaas F

2014-01-01

International audience; In this paper we report the detection of explosive compounds using a miniaturized gas preconcentrator (μGP) made of porous silicon (PS) filled in with Carbopack B as an adsorbent material. The μGP includes also a platinum heater patterned at the backside and fluidic connectors sealed on the glass cover. Our μGP is designed and optimized through fluidic and thermal simulations for meeting the requirements of trace explosives detection. The thermal mass of the device was...

General phenomenology of underground nuclear explosions; Phenomenologie generale des explosions nucleaires souterraines

Energy Technology Data Exchange (ETDEWEB)

Derlich, S; Supiot, F [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

1969-07-01

An essentially qualitatively description is given of the phenomena related to underground nuclear explosions (explosion of a single unit, of several units in line, and simultaneous explosions). In the first chapter are described the phenomena which are common to contained explosions and to explosions forming craters (formation and propagation of a shock-wave causing the vaporization, the fusion and the fracturing of the medium). The second chapter describes the phenomena related to contained explosions (formation of a cavity with a chimney). The third chapter is devoted to the phenomenology of test explosions which form a crater; it describes in particular the mechanism of formation and the different types of craters as a function of the depth of the explosion and of the nature of the ground. The aerial phenomena connected with explosions which form a crater: shock wave in the air and focussing at a large distance, and dust clouds, are also dealt with. (authors) [French] On donne une description essentiellement qualitative des phenomenes lies aux explosions nucleaires souterraines (explosion d'un seul engin, d'engins en ligne et explosions simultanees). Dans un premier chapitre sont decrits les phenomenes communs aux explosions contenues et aux explosions formant un cratere (formation et propagation d'une onde de choc provoquant la vaporisation, la fusion et la fracturation du milieu). Le deuxieme chapitre decrit les phenomenes lies aux tirs contenus (formation d'une cavite et d'une cheminee). Le troisieme chapitre est consacre a la phenomenologie des tirs formant un cratere et decrit notamment le mecanisme de formation et les differents types de crateres en fonction de la profondeur d'explosion et de la nature du terrain. Les phenomenes aeriens lies aux explosions formant un cratere: onde de pression aerienne et focalisation a grande distance, nuages de poussieres, sont egalement abordes. (auteurs)

Explosive component acceptance tester using laser interferometer technology

Science.gov (United States)

Wickstrom, Richard D.; Tarbell, William W.

1993-01-01

Acceptance testing of explosive components requires a reliable and simple to use testing method that can discern less than optimal performance. For hot-wire detonators, traditional techniques use dent blocks or photographic diagnostic methods. More complicated approaches are avoided because of their inherent problems with setup and maintenance. A recently developed tester is based on using a laser interferometer to measure the velocity of flying plates accelerated by explosively actuated detonators. Unlike ordinary interferometers that monitor displacement of the test article, this device measures velocity directly and is commonly used with non-spectral surfaces. Most often referred to as the VISAR technique (Velocity Interferometer System for Any Reflecting Surface), it has become the most widely-accepted choice for accurate measurement of velocity in the range greater than 1 mm/micro-s. Traditional VISAR devices require extensive setup and adjustment and therefore are unacceptable in a production-testing environment. This paper describes a new VISAR approach which requires virtually no adjustments, yet provides data with accuracy comparable to the more complicated systems. The device, termed the Fixed-Cavity VISAR, is currently being developed to serve as a product verification tool for hot-wire detonators and slappers. An extensive data acquisition and analysis computer code was also created to automate the manipulation of raw data into final results.

A Hydrogen Ignition Mechanism for Explosions in Nuclear Facility Piping Systems

Energy Technology Data Exchange (ETDEWEB)

Leishear, Robert A.

2013-09-18

Hydrogen explosions may occur simultaneously with water hammer accidents in nuclear facilities, and a theoretical mechanism to relate water hammer to hydrogen deflagrations and explosions is presented herein. Hydrogen and oxygen generation due to the radiolysis of water is a recognized hazard in pipe systems used in the nuclear industry, where the accumulation of hydrogen and oxygen at high points in the pipe system is expected, and explosive conditions may occur. Pipe ruptures in nuclear reactor cooling systems were attributed to hydrogen explosions inside pipelines, i.e., Hamaoka, Nuclear Power Station in Japan, and Brunsbuettel in Germany. Prior to these accidents, an ignition source for hydrogen was not clearly demonstrated, but these accidents demonstrated that a mechanism was, in fact, available to initiate combustion and explosion. A new theory to identify an ignition source and explosion cause is presented here, and further research is recommended to fully understand this explosion mechanism.

PERFORMANCE EVALUATION OF TYPE I MARINE SANITATION DEVICES

Science.gov (United States)

This performance test was designed to evaluate the effectiveness of two Type I Marine Sanitation Devices (MSDs): the Electro Scan Model EST 12, manufactured by Raritan Engineering Company, Inc., and the Thermopure-2, manufactured by Gross Mechanical Laboratories, Inc. Performance...

Systems Approach to Defeating Maritime Improvised Explosive Devices in U.S. Ports

Science.gov (United States)

2008-12-01

with a few pounds of explosive in plastic pipes and a timer wrapped in trash bags to keep it afloat. One possible target was presidential hopeful...sonar, laser, gps, control system Benthos Modem Network REMUS reference Bouy WIFI Few equipment and parts N.A 5 3 2 1 5 4 Reliability prediction

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

Science.gov (United States)

Zhang, Zhichao; Ye, Longzhen

2018-04-01

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

An integral condition for core-collapse supernova explosions

International Nuclear Information System (INIS)

Murphy, Jeremiah W.; Dolence, Joshua C.

2017-01-01

Here, we derive an integral condition for core-collapse supernova (CCSN) explosions and use it to construct a new diagnostic of explodability. The fundamental challenge in CCSN theory is to explain how a stalled accretion shock revives to explode a star. In this manuscript, we assume that the shock revival is initiated by the delayed-neutrino mechanism and derive an integral condition for spherically symmetric shock expansion, v_s > 0. One of the most useful one-dimensional explosion conditions is the neutrino luminosity and mass-accretion rate (L_ν-- M-dot ) critical curve. Below this curve, steady-state stalled solutions exist, but above this curve, there are no stalled solutions. Burrows & Goshy suggested that the solutions above this curve are dynamic and explosive. In this manuscript, we take one step closer to proving this supposition; we show that all steady solutions above this curve have v_s > 0. Assuming that these steady v_s > 0 solutions correspond to explosion, we present a new dimensionless integral condition for explosion, Ψ > 0. Ψ roughly describes the balance between pressure and gravity, and we show that this parameter is equivalent to the τ condition used to infer the L_ν-- M-dot critical curve. The illuminating difference is that there is a direct relationship between Ψ and v_s. Below the critical curve, Ψ may be negative, positive, and zero, which corresponds to receding, expanding, and stalled-shock solutions. At the critical curve, the minimum Ψ solution is zero; above the critical curve, Ψ_m_i_n > 0, and all steady solutions have v_s > 0. Using one-dimensional simulations, we confirm our primary assumptions and verify that Ψ_m_i_n > 0 is a reliable and accurate explosion diagnostic.

Microcantilever technology for law enforcement and anti-terrorism applications: chemical, biological, and explosive material detection

Science.gov (United States)

Adams, J. D.; Rogers, B.; Whitten, R.

2005-05-01

The remarkable sensitivity, compactness, low cost, low power-consumption, scalability, and versatility of microcantilever sensors make this technology among the most promising solutions for detection of chemical and biological agents, as well as explosives. The University of Nevada, Reno, and Nevada Nanotech Systems, Inc (NNTS) are currently developing a microcantilever-based detection system that will measure trace concentrations of explosives, toxic chemicals, and biological agents in air. A baseline sensor unit design that includes the sensor array, electronics, power supply and air handling has been created and preliminary demonstrations of the microcantilever platform have been conducted. The envisioned device would measure about two cubic inches, run on a small watch battery and cost a few hundred dollars. The device could be operated by untrained law enforcement personnel. Microcantilever-based devices could be used to "sniff out" illegal and/or hazardous chemical and biological agents in high traffic public areas, or be packaged as a compact, low-power system used to monitor cargo in shipping containers. Among the best detectors for such applications at present is the dog, an animal which is expensive, requires significant training and can only be made to work for limited time periods. The public is already accustomed to explosives and metal detection systems in airports and other public venues, making the integration of the proposed device into such security protocols straightforward.

Explosive strength training improves speed and agility in wheelchair basketball athletes

Directory of Open Access Journals (Sweden)

Tarik Ozmen

2014-04-01

Full Text Available INTRODUCTION: Wheelchair basketball is a paralympic sport characterized by intermittent high-intensity activities that require explosive strength and speed. OBJECTIVE: To investigate the effect of explosive strength training on speed and agility performance in wheelchair basketball players. METHODS: Ten male wheelchair basketball players (Mage=31±4 yrs were divided into two groups [i.e. explosive strength training (ES; control (CN] based on International Wheelchair Basketball Federation (IWBF classification scores. The ES group underwent 6-weeks of training, twice weekly, at 50% 1RM, 10-12 repetitions and 3-4 sets in addition to routine training. Effects of training were measured by the 20 m sprint test and Illinois agility test. RESULTS: The ES group, showed significantly higher increases in speed and agility performance (p ≤ .05. CONCLUSION: A short-duration (i.e. 6-week explosive strength training programme in wheelchair basketball athletes results in significant improvements in sprint and agility performance.

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.

Novel methods for detecting buried explosive devices

Energy Technology Data Exchange (ETDEWEB)

Kercel, S.W.; Burlage, R.S.; Patek, D.R.; Smith, C.M. [Oak Ridge National Lab., TN (United States); Hibbs, A.D.; Rayner, T.J. [Quantum Magnetics, Inc., San Diego, CA (United States)

1997-04-01

Oak Ridge National Laboratory (ORNL) and Quantum Magnetics, Inc. (QM) are exploring novel landmine detection technologies. Technologies considered here include bioreporter bacteria, swept acoustic resonance, nuclear quadrupole resonance (NQR), and semiotic data fusion. Bioreporter bacteria look promising for third-world humanitarian applications; they are inexpensive, and deployment does not require high-tech methods. Swept acoustic resonance may be a useful adjunct to magnetometers in humanitarian demining. For military demining, NQR is a promising method for detecting explosive substances; of 50,000 substances that have been tested, none has an NQR signature that can be mistaken for RDX or TNT. For both military and commercial demining, sensor fusion entails two daunting tasks, identifying fusible features in both present-day and emerging technologies, and devising a fusion algorithm that runs in real-time on cheap hardware. Preliminary research in these areas is encouraging. A bioreporter bacterium for TNT detection is under development. Investigation has just started in swept acoustic resonance as an approach to a cheap mine detector for humanitarian use. Real-time wavelet processing appears to be a key to extending NQR bomb detection into mine detection, including TNT-based mines. Recent discoveries in semiotics may be the breakthrough that will lead to a robust fused detection scheme.

Experimental study on the influence of chemical sensitizer on pressure resistance in deep water of emulsion explosives

Science.gov (United States)

Liu, Lei; zhang, Zhihua; Wang, Ya; Qin, hao

2018-03-01

The study on the pressure resistance performance of emulsion explosives in deep water can provide theoretical basis for underwater blasting, deep-hole blasting and emulsion explosives development. The sensitizer is an important component of emulsion explosives. By using reusable experimental devices to simulate the charge environment in deep water, the influence of the content of chemical sensitizer on the deep-water pressure resistance performance of emulsion explosives was studied. The experimental results show that with the increasing of the content of chemical sensitizer, the deep-water pressure resistance performance of emulsion explosives gradually improves, and when the pressure is fairly large, the effect is particularly pronounced; in a certain range, with the increase of the content of chemical sensitizer, that emulsion explosives’ explosion performance also gradually improve, but when the content reaches a certain value, the explosion properties declined instead; under the same emulsion matrix condition, when the content of NANO2 is 0.2%, that the emulsion explosives has good resistance to water pressure and good explosion properties. The correctness of the results above was testified in model blasting.

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.

Understanding vented gas explosions

Energy Technology Data Exchange (ETDEWEB)

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

1998-12-31

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.

Explosive material treatment in particular the explosive compaction of powders

International Nuclear Information System (INIS)

Pruemmer, R.

1985-01-01

The constructive use of explosives in the last decades has led to new procedures in manufacturing techniques. The most important of these are explosive forming and cladding, the latter especially for the production of compound materials. The method of explosive compaction has the highest potential for further innovation. Almost theoretical densities are achievable in the green compacts as the pressure released by detonating explosives are very high. Also, the production of new conditions of materials (metastable high pressure phases) is possible. (orig.) [de

The nonproliferation treaty and peaceful uses of nuclear explosives

Energy Technology Data Exchange (ETDEWEB)

Ehrlich, Thomas [School of Law, Stanford University, CA (United States)

1970-05-01

In the past, nuclear arms control and peaceful uses of nuclear explosives were seen by many proponents of each as competing - if not opposing - interests. At one extreme, some viewed peaceful uses as an annoying irritant on the way to general and complete disarmament. At the other extreme, some considered arms-control arrangements - particularly those limiting nuclear testing - as bothersome barriers to realizing the full benefits of peaceful nuclear explosions. Most people found themselves somewhere between those extremes. But most also felt a continuing tension between essentially opposing forces. This polarity has been significantly altered by the 1968 Treaty on the Nonproliferation of Nuclear Weapons. It is believed that the future use of nuclear explosives for peaceful purposes will depend in large measure on the international arrangements worked out under the treaty. I also believe that the success of the treaty in checking proliferation of nuclear weapons is contingent, in substantial part, on those peaceful-uses arrangements. In the areas covered by the treaty, therefore, one could view an active development of peaceful uses for nuclear explosives as complementing rather than conflicting with nuclear arms control. The treaty is primarily a security agreement. It is aimed at reducing the risk of nuclear war by establishing permanency in the current separation of nuclear-weapon and non-nuclear-weapon nations. By its terms, each nuclear-weapon state agrees not to transfer nuclear weapons or other nuclear explosive devices to any recipient, and each non-nuclear-weapon state agrees not to receive such weapons or devices. The non-nuclear- weapon parties are also obligated to negotiate safeguards agreements with the International Atomic Energy Agency covering peaceful-uses activities. And all signatories agree not to transfer fissionable material to those parties unless they are subject to such agreements. These provisions are all part of a scheme to limit the

The nonproliferation treaty and peaceful uses of nuclear explosives

International Nuclear Information System (INIS)

Ehrlich, Thomas

1970-01-01

In the past, nuclear arms control and peaceful uses of nuclear explosives were seen by many proponents of each as competing - if not opposing - interests. At one extreme, some viewed peaceful uses as an annoying irritant on the way to general and complete disarmament. At the other extreme, some considered arms-control arrangements - particularly those limiting nuclear testing - as bothersome barriers to realizing the full benefits of peaceful nuclear explosions. Most people found themselves somewhere between those extremes. But most also felt a continuing tension between essentially opposing forces. This polarity has been significantly altered by the 1968 Treaty on the Nonproliferation of Nuclear Weapons. It is believed that the future use of nuclear explosives for peaceful purposes will depend in large measure on the international arrangements worked out under the treaty. I also believe that the success of the treaty in checking proliferation of nuclear weapons is contingent, in substantial part, on those peaceful-uses arrangements. In the areas covered by the treaty, therefore, one could view an active development of peaceful uses for nuclear explosives as complementing rather than conflicting with nuclear arms control. The treaty is primarily a security agreement. It is aimed at reducing the risk of nuclear war by establishing permanency in the current separation of nuclear-weapon and non-nuclear-weapon nations. By its terms, each nuclear-weapon state agrees not to transfer nuclear weapons or other nuclear explosive devices to any recipient, and each non-nuclear-weapon state agrees not to receive such weapons or devices. The non-nuclear- weapon parties are also obligated to negotiate safeguards agreements with the International Atomic Energy Agency covering peaceful-uses activities. And all signatories agree not to transfer fissionable material to those parties unless they are subject to such agreements. These provisions are all part of a scheme to limit the

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.

Pruning-Based, Energy-Optimal, Deterministic I/O Device Scheduling for Hard Real-Time Systems

Science.gov (United States)

2005-02-01

However, DPM via I/O device scheduling for hard real - time systems has received relatively little attention. In this paper,we present an offline I/O...polynomial time. We present experimental results to show that EDS and MDO reduce the energy consumption of I/O devices significantly for hard real - time systems .

Study by Monte Carlo methods of an explosives detection system made up with a D-D neutron generator and NaI(Tl) gamma detectors.

Science.gov (United States)

Cevallos Robalino, Lenin E; García Fernández, Gonzalo Felipe; Gallego, Eduardo; Guzmán-García, Karen A; Vega-Carrillo, Hector Rene

2018-02-17

Detection of hidden explosives is of utmost importance for homeland security. Several configurations of an Explosives Detection System (EDS) to intercept hidden threats, made up with a Deuterium-Deuterium (D-D) compact neutron generator and NaI (Tl) scintillation detectors, have been evaluated using MCNP6 code. The system's response to various samples of explosives, such as RDX and Ammonium Nitrate, is analysed. The D-D generator is able to produce fast neutrons with 2.5 MeV energy in a maximum yield of 10 10 n/s. It is surrounded by high-density polyethylene to thermalize the fast neutrons and to optimize interactions with the sample inspected, whose emission of gamma rays gives a characteristic spectrum of the elements that constitute it. This procedure allows to determine its chemical composition and to identify the type of substance. The necessary shielding is evaluated to estimate its thicknesses depending on the admissible dose of operation, using lead and polyethylene. The results show that its functionality is promising in the field of national security for explosives inspection. Copyright © 2018 Elsevier Ltd. All rights reserved.

40 CFR 63.3350 - If I use a control device to comply with the emission standards, what monitoring must I do?

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 12 2010-07-01 2010-07-01 true If I use a control device to comply with the emission standards, what monitoring must I do? 63.3350 Section 63.3350 Protection of... for Monitoring and Performance Tests § 63.3350 If I use a control device to comply with the emission...

The detection of improvised nonmilitary peroxide based explosives using a titania nanotube array sensor

International Nuclear Information System (INIS)

Banerjee, Subarna; Mohapatra, Susanta K; Misra, Mano; Mishra, Indu B

2009-01-01

There is a critical need to develop an efficient, reliable and highly selective sensor for the detection of improvised nonmilitary explosives. This paper describes the utilization of functionalized titania nanotube arrays for sensing improvised organic peroxide explosives such as triacetone triperoxide (TATP). TATP forms complexes with titania nanotube arrays (prepared by anodization and sensitized with zinc ions) and thus affects the electron state of the nanosensing device, which is signaled as a change in current of the overall nanotube material. The response is rapid and a signal of five to eight orders of magnitude is observed. These nanotube array sensors can be used as hand-held miniaturized devices as well as large scale portable units for military and homeland security applications.

The detection of improvised nonmilitary peroxide based explosives using a titania nanotube array sensor.

Science.gov (United States)

Banerjee, Subarna; Mohapatra, Susanta K; Misra, Mano; Mishra, Indu B

2009-02-18

There is a critical need to develop an efficient, reliable and highly selective sensor for the detection of improvised nonmilitary explosives. This paper describes the utilization of functionalized titania nanotube arrays for sensing improvised organic peroxide explosives such as triacetone triperoxide (TATP). TATP forms complexes with titania nanotube arrays (prepared by anodization and sensitized with zinc ions) and thus affects the electron state of the nanosensing device, which is signaled as a change in current of the overall nanotube material. The response is rapid and a signal of five to eight orders of magnitude is observed. These nanotube array sensors can be used as hand-held miniaturized devices as well as large scale portable units for military and homeland security applications.

Explosive coalescence of magnetic islands and explosive particle acceleration

International Nuclear Information System (INIS)

Tajima, T.; Sakai, J.I.

1985-07-01

An explosive reconnection process associated with the nonlinear evolution of the coalescence instability is found through studies of the electromagnetic particle simulation and the magnetohydrodynamic particle simulation. The explosive coalescence is a process of magnetic collapse, in which we find the magnetic and electrostatic field energies and temperatures (ion temperature in the coalescing direction, in particular) explode toward the explosion time t 0 as (t 0 - t)/sup -8/3/, (t 0 - t) -4 , and (t 0 - t)/sup -8/3/, respectively for a canonical case. Single-peak, double-peak, and triple-peak structures of magnetic energy, temperature, and electrostatic energy, respectively, are observed on the simulation as overshoot amplitude oscillations and are theoretically explained. The heuristic model of Brunel and Tajima is extended to this explosive coalescence in order to extract the basic process. Since the explosive coalescence exhibits self-similarity, a temporal universality, we theoretically search for a self-similar solution to the two-fluid plasma equations

75 FR 1085 - Commerce in Explosives; List of Explosive Materials (2009R-18T)

Science.gov (United States)

2010-01-08

... sensitive slurry and water gel explosives. Blasting caps. Blasting gelatin. Blasting powder. BTNEC [bis.... Explosive conitrates. Explosive gelatins. Explosive liquids. Explosive mixtures containing oxygen-releasing... powder. Fulminate of mercury. Fulminate of silver. Fulminating gold. Fulminating mercury. Fulminating...

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

Science.gov (United States)

2010-11-17

..., including non-cap sensitive slurry and water gel explosives. Blasting caps. Blasting gelatin. Blasting.... Explosive conitrates. Explosive gelatins. Explosive liquids. Explosive mixtures containing oxygen-releasing... powder. Fulminate of mercury. Fulminate of silver. Fulminating gold. Fulminating mercury. Fulminating...

Wireless device for activation of an underground shock wave absorber

Science.gov (United States)

Chikhradze, M.; Akhvlediani, I.; Bochorishvili, N.; Mataradze, E.

2011-10-01

The paper describes the mechanism and design of the wireless device for activation of energy absorber for localization of blast energy in underground openings. The statistics shows that the greatest share of accidents with fatal results associate with explosions in coal mines due to aero-methane and/or air-coal media explosion. The other significant problem is terrorist or accidental explosions in underground structures. At present there are different protective systems to reduce the blast energy. One of the main parts of protective Systems is blast Identification and Registration Module. The works conducted at G. Tsulukidze Mining Institute of Georgia enabled to construct the wireless system of explosion detection and mitigation of shock waves. The system is based on the constant control on overpressure. The experimental research continues to fulfill the system based on both threats, on the constant control on overpressure and flame parameters, especially in underground structures and coal mines. Reaching the threshold value of any of those parameters, the system immediately starts the activation. The absorber contains a pyrotechnic device ensuring the discharge of dispersed water. The operational parameters of wireless device and activation mechanisms of pyrotechnic element of shock wave absorber are discussed in the paper.

Impacts of explosive compounds on vegetation: A need for community scale investigations

International Nuclear Information System (INIS)

Via, Stephen M.; Zinnert, Julie C.

2016-01-01

Explosive compounds are distributed heterogeneously across the globe as a result of over a century of human industrial and military activity. RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and TNT (2-methyl-1,3,5-trinitrobenzene) are the most common and most abundant explosives in the environment. Vegetation exhibits numerous physiological and morphological stress responses in the presence of RDX and TNT. Varied stress responses act as physiological filters that facilitate the proliferation of tolerant species and the extirpation of intolerant species. Contaminants alter community composition as they differentially impact plants at each life stage (i.e. germination, juvenile, adult), subsequently modifying larger scale ecosystem processes. This review summarizes the current explosives-vegetation literature, focusing on RDX and TNT as these are well documented in the literature, linking our current understanding to ecological theory. A conceptual framework is provided that will aid future efforts in predicting plant community response to residual explosive compounds. - Highlights: • There is a strong need for community scale explosives research. • Contaminants alter community composition as they impact plants at each life stage. • These small scale changes modify larger scale ecosystem processes. • This review summarizes the current explosives-vegetation literature. • We focus on RDX and TNT as these are well documented in the literature. - Explosives act as physiological filters that alter community composition as they differentially affect plants at each life stage (i.e. germination, juvenile, adult).

Sorbent Film-Coated Passive Samplers for Explosives Vapour Detection Part A: Materials Optimisation and Integration with Analytical Technologies.

Science.gov (United States)

McEneff, Gillian L; Murphy, Bronagh; Webb, Tony; Wood, Dan; Irlam, Rachel; Mills, Jim; Green, David; Barron, Leon P

2018-04-11

A new thin-film passive sampler is presented as a low resource dependent and discrete continuous monitoring solution for explosives-related vapours. Using 15 mid-high vapour pressure explosives-related compounds as probes, combinations of four thermally stable substrates and six film-based sorbents were evaluated. Meta-aramid and phenylene oxide-based materials showed the best recoveries from small voids (~70%). Analysis was performed using liquid chromatography-high resolution accurate mass spectrometry which also enabled tentative identification of new targets from the acquired data. Preliminary uptake kinetics experiments revealed plateau concentrations on the device were reached between 3-5 days. Compounds used in improvised explosive devices, such as triacetone triperoxide, were detected within 1 hour and were stably retained by the sampler for up to 7 days. Sampler performance was consistent for 22 months after manufacture. Lastly, its direct integration with currently in-service explosives screening equipment including ion mobility spectrometry and thermal desorption mass spectrometry is presented. Following exposure to several open environments and targeted interferences, sampler performance was subsequently assessed and potential interferences identified. High-security building and area monitoring for concealed explosives using such cost-effective and discrete passive samplers can add extra assurance to search routines while minimising any additional burden on personnel or everyday site operation.

An Impaled Potential Unexploded Device in the Civilian Training Trauma Setting: A Case Report and Review of the Literature

Science.gov (United States)

2017-12-11

responsibility.(!) 62 Additionally, eme rgency physicians need to know how to manage a patient with 63 an impaled unexploded device. Improper...his leg during the explosion. He was evaluated by EMS in 76 the field where his limb was noted to be grossly unstable with a large anterior soft 77...including roadside 127 explosives, explosive formed projectile devices and suicide bombs .(S) 128 In the United States military medical literature

Mobile Digital Recording: Adequacy of the iRig and iOS Device for Acoustic and Perceptual Analysis of Normal Voice.

Science.gov (United States)

Oliveira, Gisele; Fava, Gaetano; Baglione, Melody; Pimpinella, Michael

2017-03-01

To determine whether the iRig and iOS device recording system is comparable with a standard computer recording system for digital voice recording. Thirty-seven vocally healthy adults, between ages 20 and 62, with a mean age of 33.9 years, 13 males and 24 females, were recruited. Recordings were simultaneously digitalized in an iPad and iPhone using a unidirectional condenser microphone for smartphones/tablets (iRig Mic, IK Multimedia) and in a computer laptop (Dell-Inspiron) using a unidirectional condenser microphone (Samson-CL5) connected to a preamplifier with phantom power. Both microphones were lined up at an equal fixed distance from the subject's mouth. Speech tasks consisted of a sustained vowel "ah" at comfortable pitch/loudness, counting from 1 to 10, and a glissando "ah" from a low to a high note. The samples captured on the iOS devices were transferred via SoundCloud in WAV format, and analyzed using the Praat software. The acoustic parameters measured were mean, min, and max F0, SD F0, jitter local, jitter rap, jitter ppq5, jitter ddp, shimmer local, shimmer local-dB, shimmer apq3, shimmer apq5, shimmer apq11, shimmer dda, NHR, and HNR. There were no statistically significant differences for any parameter and speech task analyzed for both iOS devices as compared with the gold standard computer/preamp system (all P values > 0.050). In addition, there were no statistical differences in the perceptual identification of the recordings among devices (P device may provide reliable digital recording of normal voices. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

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

Energy Technology Data Exchange (ETDEWEB)

Wooten, Hasani Omar [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Aslam, Tariq Dennis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Whitley, Von Howard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-12-12

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

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.

Keanakākoʻi Tephra produced by 300 years of explosive eruptions following collapse of Kīlauea's caldera in about 1500 CE

Science.gov (United States)

Swanson, Donald A.; Rose, Timothy R.; Fiske, Richard S.; McGeehin, John P.

2012-01-01

The Keanakākoʻi Tephra at Kīlauea Volcano has previously been interpreted by some as the product of a caldera-forming eruption in 1790 CE. Our study, however, finds stratigraphic and 14C evidence that the tephra instead results from numerous eruptions throughout a 300-year period between about 1500 and 1800. The stratigraphic evidence includes: (1) as many as six pure lithic ash beds interleaved in sand dunes made of earlier Keanakākoʻi vitric ash, (2) three lava flows from Kīlauea and Mauna Loa interbedded with the tephra, (3) buried syneruptive cultural structures, (4) numerous intraformational water-cut gullies, and (5) abundant organic layers rich in charcoal within the tephra section. Interpretation of 97 new accelerator mass spectrometry (AMS) 14C ages and 4 previous conventional ages suggests that explosive eruptions began in 1470–1510 CE, and that explosive activity continued episodically until the early 1800s, probably with two periods of quiescence lasting several decades. Kīlauea's caldera, rather than forming in 1790, predates the first eruption of the Keanakākoʻi and collapsed in 1470–1510, immediately following, and perhaps causing, the end of the 60-year-long, 4–6 km3 ʻAilāʻau eruption from the east side of Kīlauea's summit area. The caldera was several hundred meters deep when the Keanakākoʻi began erupting, consistent with oral tradition, and probably had a volume of 4–6 km3. The caldera formed by collapse, but no eruption of lava coincided with its formation. A large volume of magma may have quickly drained from the summit reservoir and intruded into the east rift zone, perhaps in response to a major south-flank slip event, leading to summit collapse. Alternatively, magma may have slowly drained from the reservoir during the prolonged ʻAilāʻau eruption, causing episodic collapses before the final, largest downdrop took place. Two prolonged periods of episodic explosive eruptions are known at Kīlauea, the Keanakākoʻi

Keanakākoʻi Tephra produced by 300 years of explosive eruptions following collapse of Kīlauea's caldera in about 1500 CE

Science.gov (United States)

Swanson, Donald A.; Rose, Timothy R.; Fiske, Richard S.; McGeehin, John P.

2012-01-01

The Keanakākoʻi Tephra at Kīlauea Volcano has previously been interpreted by some as the product of a caldera-forming eruption in 1790 CE. Our study, however, finds stratigraphic and 14C evidence that the tephra instead results from numerous eruptions throughout a 300-year period between about 1500 and 1800. The stratigraphic evidence includes: (1) as many as six pure lithic ash beds interleaved in sand dunes made of earlier Keanakākoʻi vitric ash, (2) three lava flows from Kīlauea and Mauna Loa interbedded with the tephra, (3) buried syneruptive cultural structures, (4) numerous intraformational water-cut gullies, and (5) abundant organic layers rich in charcoal within the tephra section. Interpretation of 97 new accelerator mass spectrometry (AMS) 14C ages and 4 previous conventional ages suggests that explosive eruptions began in 1470–1510 CE, and that explosive activity continued episodically until the early 1800s, probably with two periods of quiescence lasting several decades. Kīlauea's caldera, rather than forming in 1790, predates the first eruption of the Keanakākoʻi and collapsed in 1470–1510, immediately following, and perhaps causing, the end of the 60-year-long, 4–6 km3 ʻAilāʻau eruption from the east side of Kīlauea's summit area. The caldera was several hundred meters deep when the Keanakākoʻi began erupting, consistent with oral tradition, and probably had a volume of 4–6 km3. The caldera formed by collapse, but no eruption of lava coincided with its formation. A large volume of magma may have quickly drained from the summit reservoir and intruded into the east rift zone, perhaps in response to a major south-flank slip event, leading to summit collapse. Alternatively, magma may have slowly drained from the reservoir during the prolonged ʻAilāʻau eruption, causing episodic collapses before the final, largest downdrop took place. Two prolonged periods of episodic explosive eruptions are known at Kīlauea, the Keanakākoʻi

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

Science.gov (United States)

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

2016-01-01

Steam explosion pretreatment has been examined in many studies for enhancing the enzymatic digestibility of lignocellulosic biomass and is currently the most common pretreatment method in commercial biorefineries. The information available about the effect of the explosive decompression on the biochemical conversion is, however, very limited, and no studies prove that the latter is actually enhanced by the explosion. Hence, it is of great value to discern between the effect of the explosion on the one hand and the steaming on the other hand, to identify their particular influences on enzymatic digestibility. The effect of the explosive decompression in the steam explosion pretreatment of spruce wood chips on their enzymatic cellulose digestibility was studied systematically. The explosion had a high influence on digestibility, improving it by up to 90 % compared to a steam pretreatment without explosion. Two factors were identified to be essentially responsible for the effect of the explosion on enzymatic digestibility: pretreatment severity and pressure difference of the explosion. A higher pretreatment severity can soften up and weaken the lignocellulose structure more, so that the explosion can better break up the biomass and decrease its particle size, which enhances its digestibility. In particular, increasing the pressure difference of the explosion leads to more defibration, a smaller particle size and a better digestibility. Though differences were found in the micro- and nanostructure of exploded and non-exploded biomass, the only influence of the explosion on digestibility was found to be the macroscopic particle size reduction. Steam explosion treatments with a high severity and a high pressure difference of the explosion lead to a comparatively high cellulose digestibility of the-typically very recalcitrant-softwood biomass. This is the first study to show that explosion can enhance the enzymatic digestibility of lignocellulosic biomass. If the

A fast and simple approach for the estimation of a radiological source from localised measurements after the explosion of a radiological dispersal device

International Nuclear Information System (INIS)

Urso, L.; Kaiser, J.C.; Woda, C.; Helebrant, J.; Hulka, J.; Kuca, P.; Prouza, Z.

2014-01-01

After an explosion of a radiological dispersal device, decision-makers need to implement countermeasures as soon as possible to minimise the radiation-induced risks to the population. In this work, the authors present a tool, which can help providing information about the approximate size of source term and radioactive contamination based on a Gaussian Plume model with the use of available measurements for liquid or aerosolised radioactivity. For two-field tests, the source term and spatial distribution of deposited radioactivity are estimated. A sensitivity analysis of the dependence on deposition velocity is carried out. In case of weak winds, a diffusive process along the wind direction is retained in the model. (authors)

Collection of trace evidence of explosive residues from the skin in a death due to a disguised letter bomb. The synergy between confocal laser scanning microscope and inductively coupled plasma atomic emission spectrometer analyses.

Science.gov (United States)

Turillazzi, Emanuela; Monaci, Fabrizio; Neri, Margherita; Pomara, Cristoforo; Riezzo, Irene; Baroni, Davide; Fineschi, Vittorio

2010-04-15

In most deaths caused by explosive, the victim's body becomes a depot for fragments of explosive materials, so contributing to the collection of trace evidence which may provide clues about the specific type of device used with explosion. Improvised explosive devices are used which contain "homemade" explosives rather than high explosives because of the relative ease with which such components can be procured. Many methods such as chromatography-mass spectrometry, scanning electron microscopy, stereomicroscopy, capillary electrophoresis are available for use in the identification of explosive residues on objects and bomb fragments. Identification and reconstruction of the distribution of explosive residues on the decedent's body may give additional hints in assessing the position of the victim in relation to the device. Traditionally these residues are retrieved by swabbing the body and clothing during the early phase, at autopsy. Gas chromatography-mass spectrometry and other analytical methods may be used to analyze the material swabbed from the victim body. The histological examination of explosive residues on skin samples collected during the autopsy may reveal significant details. The information about type, quantity and particularly about anatomical distribution of explosive residues obtained utilizing confocal laser scanning microscope (CLSM) together with inductively coupled plasma atomic emission spectrometer (ICP-AES), may provide very significant evidence in the clarification and reconstruction of the explosive-related events. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Loose-Lipped Mobile Device Intelligent Personal Assistants: A Discussion of Information Gleaned from Siri on Locked iOS Devices.

Science.gov (United States)

Horsman, Graeme

2018-04-23

The forensic analysis of mobile handsets is becoming a more prominent factor in many criminal investigations. Despite such devices frequently storing relevant evidential content to support an investigation, accessing this information is becoming an increasingly difficult task due to enhanced effective security features. Where access to a device's resident data is not possible via traditional mobile forensic methods, in some cases it may still be possible to extract user information via queries made to an installed intelligent personal assistant. This article presents an evaluation of the information which is retrievable from Apple's Siri when interacted with on a locked iOS device running iOS 11.2.5 (the latest at the time of testing). The testing of verbal commands designed to elicit a response from Siri demonstrate the ability to recover call log, SMS, Contacts, Apple Maps, Calendar, and device information which may support any further investigation. © 2018 American Academy of Forensic Sciences.

Underbody Blast Models of TBI Caused by Hyper-Acceleration and Secondary Head Impact

Science.gov (United States)

2017-10-01

brain injury (TBI), with most of these head injuries caused by explosive munitions such as bombs , land mines, improvised explosive devices and missiles...with most of these injuries caused by explosive munitions such as bombs , land mines, improvised explosive devices (IEDs), and missiles.1,2 Little is...Neurosurg. 2008;108: 124–131. 21. Richards EM , Fiskum G, Rosenthal RE, Hopkins I, McKenna MC. Hyperoxic reperfusion after global ischemia decreases

Initiation devices, initiation systems including initiation devices and related methods

Energy Technology Data Exchange (ETDEWEB)

Daniels, Michael A.; Condit, Reston A.; Rasmussen, Nikki; Wallace, Ronald S.

2018-04-10

Initiation devices may include at least one substrate, an initiation element positioned on a first side of the at least one substrate, and a spark gap electrically coupled to the initiation element and positioned on a second side of the at least one substrate. Initiation devices may include a plurality of substrates where at least one substrate of the plurality of substrates is electrically connected to at least one adjacent substrate of the plurality of substrates with at least one via extending through the at least one substrate. Initiation systems may include such initiation devices. Methods of igniting energetic materials include passing a current through a spark gap formed on at least one substrate of the initiation device, passing the current through at least one via formed through the at least one substrate, and passing the current through an explosive bridge wire of the initiation device.

Possible hazard reduction by using distributed phased nuclear explosions

Energy Technology Data Exchange (ETDEWEB)

Chilton, Frank [Theoretical Physics Program, Stanford Research Institute, Menio Park, CA (United States); [Department of Applied Science, University of California, Davis, CA (United States); Cheney, James A [Department of Civil Engineering, University of California, Davis, CA (United States)

1970-05-15

The use of two or more nuclear devices, phased together in order to constructively add their respective particle velocities, is proposed herein. By directing the seismic waves of the nuclear explosions to make them more efficient in accomplishing the intended construction, we hope to be able to reduce the radioactivity, seismic, and airblast hazards substantially. Experiments are being performed with one gram charges of PETN. (author)

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

Energy Technology Data Exchange (ETDEWEB)

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

2006-10-01

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

A systematic study of the explosion energy issue in core collapse supernova theory

Science.gov (United States)

Yamamoto, Yu

2016-06-01

Massive stars with main sequence masses greater than 8 solar mass (Msun) the main target of CCSNe researches. According to initial mass function (IMF) they occupy about 15As a matter of fact, supernova theorists have failed to reproduce this energetic stellar explosion for about a half century because micro and macro physics are highly complex and are mutual influenced. The theoretical investigation of the explosion mechanism is based on numerical simulations, which will ultimately require computational sources of exsa scales. With recent remarkable developments both in hardware and software, however, more realistic physics are incorporated and research group are beginning to overcome the difficulties, reporting successful explosions in their numerical models. The successful is still partial, unfortunately, since in the most of the cases the explosion energy hardly reaches the typical value (10^51erg). What is worse other groups found no explosion for almost same setups. The robust explosion mechanism has not yet been ascertained and is still a remaining issue. The purpose of this paper is to study how far our understanding of "neutrino heating mechanism", the current paradigm, has reached, or put another way, to expose what kind of physics are still missing to explain observations , such as explosion energy and nickel mass. As already remarked the physics in CCSNe are quite complicated with extremely high Reynolds number, highly uncertain equation of state (EOS) at supra-nuclear densities, copious neutrinos not in thermal nor chemical equilibrium with matter normally. I believe that it is justified to devote a somewhat large number of pages to the introduction. It will be also helpful for understanding the motivation of this paper. Starting with evidence from supernova light curves I will then move to the basics idea of neutrino heating mechanism and summarize some recent developments in various micro and macro physics. Key factors in the theory of massive

Newest Developments in the German Explosive Safety Quantitative Risk Analysis Software (ESQRA-GE)

Science.gov (United States)

2010-07-01

Software (ESQRA-GE) F.K.F. Radtke , I. Stacke, C. Rizzuti, B. Brombacher, M. Voss, I. Häring Fraunhofer-Institute for High-Speed Dynamics – Ernst-Mach...Institute, Am Klingelberg 1, 79588 Efringen-Kirchen, Germany radtke @emi.fhg.de, haering@emi.fhg.de Keywords: explosive ordnance disposal, EOD...Prescribed by ANSI Std Z39-18 34th DoD Explosives Safety Seminar 2010, Portland, Oregon 2 Brief presenter biography Frank Radtke started his

Lightning vulnerability of nuclear explosive test systems at the Nevada Test Site

International Nuclear Information System (INIS)

Hasbrouck, R.T.

1985-01-01

A task force chartered to evaluate the effects of lightning on nuclear explosives at the Nevada Test Site has made several recommendations intended to provide lightning-invulnerable test device systems. When these recommendations have been implemented, the systems will be tested using full-threat-level simulated lightning

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

Science.gov (United States)

2011-10-19

... slurry and water gel explosives. Blasting caps. Blasting gelatin. Blasting powder. BTNEC [bis.... Esters of nitro-substituted alcohols. Ethyl-tetryl. Explosive conitrates. Explosive gelatins. Explosive... silver. Fulminating gold. Fulminating mercury. Fulminating platinum. Fulminating silver. G Gelatinized...

Low-frequency electromagnetic measurements as a zero-time discriminant of nuclear and chemical explosions - OSI research final report

International Nuclear Information System (INIS)

Sweeney, J.J.

1996-12-01

This is the final report on a series of investigations of low frequency (1-40 Hz) electromagnetic signals produced by above ground and underground chemical explosions and their use for confidence building under the Comprehensive Test-Ban Treaty. I conclude that low frequency electromagnetic measurements can be a very powerful tool for zero-time discrimination of chemical and nuclear explosions for yields of 1 Kt or greater, provided that sensors can be placed within 1-2 km of the suspected detonation point in a tamper-proof, low noise environment. The report includes descriptions and analyses of low frequency electromagnetic measurements associated with chemical explosions carried out in a variety of settings (shallow borehole, open pit mining, underground mining). I examine cavity pressure data from the Non-Proliferation Experiment (underground chemical explosion) and present the hypothesis that electromagnetic signals produced by underground chemical explosions could be produced during rock fracturing. I also review low frequency electromagnetic data from underground nuclear explosions acquired by Lawrence Livermore National Laboratory during the late 1980s. (author)

Short term forecasting of explosions at Ubinas volcano, Perú

Science.gov (United States)

Traversa, P.; Lengliné, O.; Macedo, O.; Metaxian, J. P.; Grasso, J. R.; Inza, A.; Taipe, E.

2011-11-01

Most seismic eruption forerunners are described using Volcano-Tectonic earthquakes, seismic energy release, deformation rates or seismic noise analyses. Using the seismic data recorded at Ubinas volcano (Perú) between 2006 and 2008, we explore the time evolution of the Long Period (LP) seismicity rate prior to 143 explosions. We resolve an average acceleration of the LP rate above the background level during the 2-3 hours preceding the explosion onset. Such an average pattern, which emerges when stacking over LP time series, is robust and stable over all the 2006-2008 period, for which data is available. This accelerating pattern is also recovered when conditioning the LP rate on the occurrence of an other LP event, rather than on the explosion time. It supports a common mechanism for the generation of explosions and LP events, the magma conduit pressure increase being the most probable candidate. The average LP rate acceleration toward an explosion is highly significant prior to the higher energy explosions, supposedly the ones associated with the larger pressure increases. The dramatic decay of the LP activity following explosions, still reinforce the strong relationship between these two processes. We test and we quantify the retrospective forecasting power of these LP rate patterns to predict Ubinas explosions. The prediction quality of the forecasts (e.g. for 17% of alarm time, we predict 63% of Ubinas explosions, with 58% of false alarms) is evaluated using error diagrams. The prediction results are stable and the prediction algorithm validated, i.e. its performance is better than the random guess.

Standardized Method for Measuring Collection Efficiency from Wipe-sampling of Trace Explosives.

Science.gov (United States)

Verkouteren, Jennifer R; Lawrence, Jeffrey A; Staymates, Matthew E; Sisco, Edward

2017-04-10

One of the limiting steps to detecting traces of explosives at screening venues is effective collection of the sample. Wipe-sampling is the most common procedure for collecting traces of explosives, and standardized measurements of collection efficiency are needed to evaluate and optimize sampling protocols. The approach described here is designed to provide this measurement infrastructure, and controls most of the factors known to be relevant to wipe-sampling. Three critical factors (the applied force, travel distance, and travel speed) are controlled using an automated device. Test surfaces are chosen based on similarity to the screening environment, and the wipes can be made from any material considered for use in wipe-sampling. Particle samples of the explosive 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) are applied in a fixed location on the surface using a dry-transfer technique. The particle samples, recently developed to simulate residues made after handling explosives, are produced by inkjet printing of RDX solutions onto polytetrafluoroethylene (PTFE) substrates. Collection efficiency is measured by extracting collected explosive from the wipe, and then related to critical sampling factors and the selection of wipe material and test surface. These measurements are meant to guide the development of sampling protocols at screening venues, where speed and throughput are primary considerations.

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

Science.gov (United States)

2012-09-20

... sensitive slurry and water gel explosives. Blasting caps. Blasting gelatin. Blasting powder. BTNEC [bis.... Esters of nitro-substituted alcohols. Ethyl-tetryl. Explosive conitrates. Explosive gelatins. Explosive.... Fulminate of silver. Fulminating gold. Fulminating mercury. Fulminating platinum. Fulminating silver. G...

Supernovae Ia in 2017: a long time delay from merger/accretion to explosion

Science.gov (United States)

Soker, Noam

2018-04-01

I use recent observational and theoretical studies of type Ia supernovae (SNe Ia) to further constrain the viable SN Ia scenarios and to argue that there must be a substantial time delay between the end of the merger of the white dwarf (WD) with a companion or the end of mass accretion on to the WD and its terminal explosion. This merger/accretion to explosion delay (MED) is required to allow the binary system to lead to a more or less spherical explosion and to prevent a pre-explosion ionizing radiation. Considering these recent results and the required MED, I conclude that the core degenerate scenario is somewhat more favorable over the other scenarios, followed by the double degenerate scenario. Although the single degenerate scenario is viable as well, it is less likely to account for common (normal) SN Ia. As all scenarios require substantial MED, the MED has turned from a disadvantage of the core degenerate scenario to a challenge that theory should overcome. I hope that the requirement for a MED will stimulate the discussion of the different SN Ia scenarios and the comparison of the scenarios to each other.

Detection of drugs and plastic explosives using neutron tomography

Energy Technology Data Exchange (ETDEWEB)

Ferreira, F.J.O. [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil)], E-mail: fferreira@ien.gov.br; Crispim, V.R; Silva, A.X. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Programa de Engenharia Nuclear], E-mail: ademir@con.ufrj.br, E-mail: verginia@com.ufrj.br

2007-07-01

The unique ability of neutrons to image certain elements and isotopes that are either completely undetectable or poorly detected by other Non-Destructive-Assay (NDA) methods makes neutron radiography an important tool for the NDA community. Neutron radiography, like other imaging techniques takes a number of different forms (i.e. / that is film, radioscopic, transfer methods, tomography, etc.) In this work report the Neutron Tomography System developed, which will allow inspections NDA of samples with high efficiency, in terms of minors measure time and the result analysis, and the application for detection of drugs and plastic explosives, which is very important for the combat to the terrorism and drug trafficking. The neutron tomography system developed is third generation. Therefore a rotary table driven by a step motor connected to a computerized motion control system has been installed at the sample position. In parallel to this a suitable electronic imaging device has been designed and can be controlled by a computer in order to synchronize the software the detector and of the rotary table with the aim of an automation of measurements. To obtain 2D tomography image, a system with an electronic imaging system for producing real time neutron radiography. Images are processing digital for cancel random noise effects and to optimize spatial resolution. Finally, using a (ARIEN) algorithm reconstruction of tomography images by finite element maximum entropy. The system was installed adjacent to the exit of the J-9 irradiation channel of the Argonauta Reactor in the Nuclear Engineering Institute (IEN) - which is an organ of the National Nuclear Energy Commission (CNEN - Brazil).The Argonauta reactor operates at 340 watts, being that the characteristics of the neutron beam on the plane of the image: thermal neutron flux 4,46 x10{sup 5} n/cm{sup 2}s. In the tomography assays, several encapsulated samples of paste, rock and cocaine powder and plastic explosives devices

Detection of drugs and plastic explosives using neutron tomography

International Nuclear Information System (INIS)

Ferreira, F.J.O.; Crispim, V.R; Silva, A.X.

2007-01-01

The unique ability of neutrons to image certain elements and isotopes that are either completely undetectable or poorly detected by other Non-Destructive-Assay (NDA) methods makes neutron radiography an important tool for the NDA community. Neutron radiography, like other imaging techniques takes a number of different forms (i.e. / that is film, radioscopic, transfer methods, tomography, etc.) In this work report the Neutron Tomography System developed, which will allow inspections NDA of samples with high efficiency, in terms of minors measure time and the result analysis, and the application for detection of drugs and plastic explosives, which is very important for the combat to the terrorism and drug trafficking. The neutron tomography system developed is third generation. Therefore a rotary table driven by a step motor connected to a computerized motion control system has been installed at the sample position. In parallel to this a suitable electronic imaging device has been designed and can be controlled by a computer in order to synchronize the software the detector and of the rotary table with the aim of an automation of measurements. To obtain 2D tomography image, a system with an electronic imaging system for producing real time neutron radiography. Images are processing digital for cancel random noise effects and to optimize spatial resolution. Finally, using a (ARIEN) algorithm reconstruction of tomography images by finite element maximum entropy. The system was installed adjacent to the exit of the J-9 irradiation channel of the Argonauta Reactor in the Nuclear Engineering Institute (IEN) - which is an organ of the National Nuclear Energy Commission (CNEN - Brazil).The Argonauta reactor operates at 340 watts, being that the characteristics of the neutron beam on the plane of the image: thermal neutron flux 4,46 x10 5 n/cm 2 s. In the tomography assays, several encapsulated samples of paste, rock and cocaine powder and plastic explosives devices. (author)

High Altitude Electromagnetic Pulse (HEMP) and High Power Microwave (HPM) Devices: Threat Assessments

National Research Council Canada - National Science Library

Wilson, Clay

2004-01-01

.... civilian computer systems to the effects of EMP has been discussed in the media. EMP can be produced on a large scale using a single nuclear explosion, and on a smaller, non-nuclear scale using a device with batteries or chemical explosives...

Underground nuclear explosions

International Nuclear Information System (INIS)

Higgins, Gary H.

1970-01-01

In the Third Plowshare Symposium, held in 1964, data from a number of nuclear explosions were presented. At that time the basic elements of the nuclear explosion appeared to be well understood and relationships for predicting the gross nuclear effects were presented. Since that time, additional work has been done and many of the concepts have been extended. For example, nuclear explosions have been conducted at greater depths and with much greater yields. The physical and chemical properties of the material in which the explosions occur have been more accurately measured and related to explosion effects. Interpretation of the new information seems to indicate that the earlier relationships are valid over the ranges of energy and depths for which data is available but that effects relating to cavity and chimney sizes or fracturing had been overestimated at great depths of burst and higher yields. (author)

Underground nuclear explosions

Energy Technology Data Exchange (ETDEWEB)

Higgins, Gary H [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-01

In the Third Plowshare Symposium, held in 1964, data from a number of nuclear explosions were presented. At that time the basic elements of the nuclear explosion appeared to be well understood and relationships for predicting the gross nuclear effects were presented. Since that time, additional work has been done and many of the concepts have been extended. For example, nuclear explosions have been conducted at greater depths and with much greater yields. The physical and chemical properties of the material in which the explosions occur have been more accurately measured and related to explosion effects. Interpretation of the new information seems to indicate that the earlier relationships are valid over the ranges of energy and depths for which data is available but that effects relating to cavity and chimney sizes or fracturing had been overestimated at great depths of burst and higher yields. (author)

RF and dc desensitized electroexplosive device

Science.gov (United States)

Krainiak, John W.; Speaks, Paul D.; Cornett, Michael S.

1989-07-01

This patent application relates to electroexplosive devices (EEDs) such as detonators, blasting caps and squibs, in particular to a method and device for desensitizing EEDs to electromagnetic radiation and electrostatic charges with the added ability to desensitize the device to essentially dc currents. An insensitive electroexplosive device to electrically ignite explosive is disclosed. This device is inherently immune to radio frequency (RF) radiation, and also provides protection against dc or very low frequency RF induced by arcing. A central feature is use of zeners and capacitors to form a reactively balanced bridge circuit. When constructed in semiconductor form, as described in this application, the device is capable of incorporation in small caliber ordnance.

Real-time volume rendering of digital medical images on an iOS device

Science.gov (United States)

Noon, Christian; Holub, Joseph; Winer, Eliot

2013-03-01

Performing high quality 3D visualizations on mobile devices, while tantalizingly close in many areas, is still a quite difficult task. This is especially true for 3D volume rendering of digital medical images. Allowing this would empower medical personnel a powerful tool to diagnose and treat patients and train the next generation of physicians. This research focuses on performing real time volume rendering of digital medical images on iOS devices using custom developed GPU shaders for orthogonal texture slicing. An interactive volume renderer was designed and developed with several new features including dynamic modification of render resolutions, an incremental render loop, a shader-based clipping algorithm to support OpenGL ES 2.0, and an internal backface culling algorithm for properly sorting rendered geometry with alpha blending. The application was developed using several application programming interfaces (APIs) such as OpenSceneGraph (OSG) as the primary graphics renderer coupled with iOS Cocoa Touch for user interaction, and DCMTK for DICOM I/O. The developed application rendered volume datasets over 450 slices up to 50-60 frames per second, depending on the specific model of the iOS device. All rendering is done locally on the device so no Internet connection is required.

System for remote control of underground device

Science.gov (United States)

Brumleve, T.D.; Hicks, M.G.; Jones, M.O.

1975-10-21

A system is described for remote control of an underground device, particularly a nuclear explosive. The system includes means at the surface of the ground for transmitting a seismic signal sequence through the earth having controlled and predetermined signal characteristics for initiating a selected action in the device. Additional apparatus, located with or adjacent to the underground device, produces electrical signals in response to the seismic signals received and compares these electrical signals with the predetermined signal characteristics.

System for remote control of underground device

International Nuclear Information System (INIS)

Brumleve, T.D.; Hicks, M.G.; Jones, M.O.

1975-01-01

A system is described for remote control of an underground device, particularly a nuclear explosive. The system includes means at the surface of the ground for transmitting a seismic signal sequence through the earth having controlled and predetermined signal characteristics for initiating a selected action in the device. Additional apparatus, located with or adjacent to the underground device, produces electrical signals in response to the seismic signals received and compares these electrical signals with the predetermined signal characteristics

Phase velocity enhancement of linear explosive shock tubes

Science.gov (United States)

Loiseau, Jason; Serge, Matthew; Szirti, Daniel; Higgins, Andrew; Tanguay, Vincent

2011-06-01

Strong, high density shocks can be generated by sequentially detonating a hollow cylinder of explosives surrounding a thin-walled, pressurized tube. Implosion of the tube results in a pinch that travels at the detonation velocity of the explosive and acts like a piston to drive a shock into the gas ahead of it. In order to increase the maximum shock velocities that can be obtained, a phase velocity generator can be used to drag an oblique detonation wave along the gas tube at a velocity much higher than the base detonation velocity of the explosive. Since yielding and failure of the gas tube is the primary limitation of these devices, it is desirable to retain the dynamic confinement effects of a heavy-walled tamper without interfering with operation of the phase velocity generator. This was accomplished by cutting a slit into the tamper and introducing a phased detonation wave such that it asymmetrically wraps around the gas tube. This type of configuration has been previously experimentally verified to produce very strong shocks but the post-shock pressure and shock velocity limits have not been investigated. This study measured the shock trajectory for various fill pressures and phase velocities to ascertain the limiting effects of tube yield, detonation obliquity and pinch aspect ratio.

Studies of radioactivity from nuclear explosions for peaceful purposes

Energy Technology Data Exchange (ETDEWEB)

Siddons, R A [AWRE, Aldermaston (United Kingdom)

1970-05-01

Estimates are made of the extent and duration of hazards from radioactivity to the general public due to fallout from a cratering explosion. The nuclear explosive is assumed to be 'clean' in the sense that only a small fraction of the yield is derived from fission. Hypothetical examples take an explosive of total yield 100 kT, of which 10 kT, 1 kT and zero - the ultimate in cleanliness - are derived from fission. The maximum permitted level to the public is taken as 0.5 rem in a period of one year. Sources of activity considered are fission products, residual thermonuclear material (tritium), neutron induced activity in the device materials and neutron induced activity in the surrounding rock. Estimates of the production are made, and are associated with a distribution function derived from the Sedan fallout measurements. The hazards from radioactivity associated with the creation of a storage reservoir for natural gas have also been considered. In this case the main problem is contamination of the product by tritium left in the chimney. The possibility of flushing out this tritium with water is discussed. (author)

Studies of radioactivity from nuclear explosions for peaceful purposes

International Nuclear Information System (INIS)

Siddons, R.A.

1970-01-01

Estimates are made of the extent and duration of hazards from radioactivity to the general public due to fallout from a cratering explosion. The nuclear explosive is assumed to be 'clean' in the sense that only a small fraction of the yield is derived from fission. Hypothetical examples take an explosive of total yield 100 kT, of which 10 kT, 1 kT and zero - the ultimate in cleanliness - are derived from fission. The maximum permitted level to the public is taken as 0.5 rem in a period of one year. Sources of activity considered are fission products, residual thermonuclear material (tritium), neutron induced activity in the device materials and neutron induced activity in the surrounding rock. Estimates of the production are made, and are associated with a distribution function derived from the Sedan fallout measurements. The hazards from radioactivity associated with the creation of a storage reservoir for natural gas have also been considered. In this case the main problem is contamination of the product by tritium left in the chimney. The possibility of flushing out this tritium with water is discussed. (author)

Stellar explosion

International Nuclear Information System (INIS)

Suraud, E.

1987-01-01

What is the energy source and which physical processes are powerful enough to generate this explosion which scatters the star. The knowledge progress of very dense matter allows the scenario reconstitution. An instability in the star core which is developing during milliseconds is the cause of this explosion [fr

Mass Spectrometric Analysis of Eight Common Chemical Explosives Using Ion Trap Mass Spectrometer

Energy Technology Data Exchange (ETDEWEB)

Park, Sehwan; Lee, Jihyeon; KIm, Jeongkwon [Chungnam National Univ., Daejeon (Korea, Republic of); Cho, Soo Gyeong; Goh, Eun Mee [Agency for Defense Development, Daejeon (Korea, Republic of); Lee, Sungman; Koh, Sungsuk [Sensor Tech Inc., Seoul (Korea, Republic of)

2013-12-15

Eight representative explosives (ammonium perchlorate (AP), ammonium nitrate (AN), trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), cyclonite (RDX), cyclotetramethylenetetranitramine (HMX), pentaerythritol tetranitrate (PETN), and hexanitrostilbene (HNS)) were comprehensively analyzed with an ion trap mass spectrometer in negative ion mode using direct infusion electrospray ionization. MS/MS experiments were performed to generate fragment ions from the major parent ion of each explosive. Explosives in salt forms such as AP or AN provided cluster parent ions with their own anions. Explosives with an aromatic ring were observed as either [M.H]{sup -} for TNT and DNT or [M]{sup ·-}. for HNS, while explosives without an aromatic ring such as RDX, HMX, and PETN were detected as an adduct ion with a formate anion, i. e., [M+HCOO]{sup -}. These findings provide a guideline for the rapid and accurate detection of explosives once portable MS instruments become more readily available.

Mass Spectrometric Analysis of Eight Common Chemical Explosives Using Ion Trap Mass Spectrometer

International Nuclear Information System (INIS)

Park, Sehwan; Lee, Jihyeon; KIm, Jeongkwon; Cho, Soo Gyeong; Goh, Eun Mee; Lee, Sungman; Koh, Sungsuk

2013-01-01

Eight representative explosives (ammonium perchlorate (AP), ammonium nitrate (AN), trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), cyclonite (RDX), cyclotetramethylenetetranitramine (HMX), pentaerythritol tetranitrate (PETN), and hexanitrostilbene (HNS)) were comprehensively analyzed with an ion trap mass spectrometer in negative ion mode using direct infusion electrospray ionization. MS/MS experiments were performed to generate fragment ions from the major parent ion of each explosive. Explosives in salt forms such as AP or AN provided cluster parent ions with their own anions. Explosives with an aromatic ring were observed as either [M.H] - for TNT and DNT or [M] ·- . for HNS, while explosives without an aromatic ring such as RDX, HMX, and PETN were detected as an adduct ion with a formate anion, i. e., [M+HCOO] - . These findings provide a guideline for the rapid and accurate detection of explosives once portable MS instruments become more readily available

Steam explosion studies review

International Nuclear Information System (INIS)

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)

Fragment capture device

Science.gov (United States)

Payne, Lloyd R.; Cole, David L.

2010-03-30

A fragment capture device for use in explosive containment. The device comprises an assembly of at least two rows of bars positioned to eliminate line-of-sight trajectories between the generation point of fragments and a surrounding containment vessel or asset. The device comprises an array of at least two rows of bars, wherein each row is staggered with respect to the adjacent row, and wherein a lateral dimension of each bar and a relative position of each bar in combination provides blockage of a straight-line passage of a solid fragment through the adjacent rows of bars, wherein a generation point of the solid fragment is located within a cavity at least partially enclosed by the array of bars.

Device Applications of Nonlinear Dynamics

CERN Document Server

Baglio, Salvatore

2006-01-01

This edited book is devoted specifically to the applications of complex nonlinear dynamic phenomena to real systems and device applications. While in the past decades there has been significant progress in the theory of nonlinear phenomena under an assortment of system boundary conditions and preparations, there exist comparatively few devices that actually take this rich behavior into account. "Device Applications of Nonlinear Dynamics" applies and exploits this knowledge to make devices which operate more efficiently and cheaply, while affording the promise of much better performance. Given the current explosion of ideas in areas as diverse as molecular motors, nonlinear filtering theory, noise-enhanced propagation, stochastic resonance and networked systems, the time is right to integrate the progress of complex systems research into real devices.

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.

The one device the secret history of the iPhone

CERN Document Server

Merchant, Brian

2017-01-01

The secret history of the invention that changed everything-and became the most profitable product in the world. Odds are that as you read this, an iPhone is within reach. But before Steve Jobs introduced us to "the one device," as he called it, a cell phone was merely what you used to make calls on the go. How did the iPhone transform our world and turn Apple into the most valuable company ever? Veteran technology journalist Brian Merchant reveals the inside story you won't hear from Cupertino-based on his exclusive interviews with the engineers, inventors, and developers who guided every stage of the iPhone's creation. This deep dive takes you from inside One Infinite Loop to 19th century France to WWII America, from the driest place on earth to a Kenyan pit of toxic e-waste, and even deep inside Shenzhen's notorious "suicide factories." It's a firsthand look at how the cutting-edge tech that makes the world work-touch screens, motion trackers, and even AI-made their way into our pockets. The One Device...

Summary of a joint US-Japan study of potential approaches to reduce the attractiveness of various nuclear materials for use in a nuclear explosive device by a terrorist group

Energy Technology Data Exchange (ETDEWEB)

Bathke, C.G. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM (United States); Inoue, N.; Kuno, Y.; Mihara, T.; Sagara, H. [Japan Atomic Energy Agency, 4-49 Muramatsu, Tokai-mura, Naka-gun, Ibaraki 319-1184 (Japan); Ebbinghaus, B.B. [Lawrence Livermore National Laboratory, P.O. Box L-168, Livermore, CA 94551 (United States); Murphy, J.; Dalton, D. [National Nuclear Security Administration, Department of Energy, 1000 Independence Ave, SW, Washington, DC 20585 (United States); Nagayama, Y. [Ministry of Education, Culture, Sports, Science and Technology, 3-2-2 Kasumigaseki, Chiyoda-ku, Tokyo 100-8959 (Japan)

2013-07-01

This paper summarizes the results of a joint US-Japan study to establish a mutual understanding, through scientific-based study, of potential approaches to reduce the attractiveness of various nuclear materials for use in a terrorist nuclear explosive device (NED). 4 approaches that can reduce materials attractiveness with a very high degree of effectiveness are: -) diluting HEU with natural or depleted U to an enrichment of less than 10% U-235; -) storing Pu in nuclear fuel that is not man portable and with a dose rate greater or equal to 10 Gy/h at 1 m; -) storing Pu or HEU in heavy items, i.e. not transportable, provided the removal of the Pu or HEU from the item requires a purification/processing capability; and -) converting Pu and HEU to very dilute forms (such as wastes) that, without any security barriers, would require very long acquisition times to acquire a Category I quantity of Pu or of HEU. 2 approaches that can reduce materials attractiveness with a high degree of effectiveness are: -) converting HEU-fueled research reactors into LEU-fueled research reactors or dilute HEU with natural or depleted U to an enrichment of less than 20% U-235; -) converting U/Al reactor fuel into U/Si reactor fuel. Other approaches have been assessed as moderately or totally inefficient to reduce the attractiveness of nuclear materials.

Analysis of the Explosive Internal Impact on the Barriers of Building Structures

Science.gov (United States)

Siwiński, Jarosław; Stolarski, Adam

2017-10-01

Work issues concern the safety of construction in relation to the hazards arising from explosion of the explosive charge located inside the building. The algorithms proposed in the paper for determining the parameters of the overpressure wave resulting from the detonation of clustered explosive charges, determine the basis for numerical simulation analyzes. Determination of the maximum value of peak pressure on the wave forehead of an internal explosion is presented on the basis of reflected wave analysis. Changeability in time of the internal explosion action describes the overpressure phase only. The analysis of the load caused by the internal explosive charge detonation was carried out under conditions of the undisturbed standard atmosphere. A load determination algorithm has been developed, taking into account the geometrical characteristics of the building barriers and the rooms as well as the parameters of environment in which the detonation occurs. The way of taking into account the influence of venting surfaces, i.e. windows, doors, ventilation ducts, on the overpressure wave parameters, was presented. Discloses a method to take into account the effect of the surface relief, i.e. windows, doors, air ducts, pressure wave parameters. Modification of the method for explosive overpressure determination presented by Cormie, Smith, Mays (2009), was proposed in the paper. This modification was developed on the basis of substitute impulse analysis for multiple overpressure pulses. In order to take into account the pressure distribution of explosive gases on the barrier surface, the method of modification the relationship for determination the changeability over time and space of the pressure of explosive gases, was presented. For this purpose, the changeability of the pressure wave angles of incidence to the barrier and the distance of the explosive charge to any point on the surface of the barrier, was taken into account. Based on the developed procedure, the

Source characterization of underground explosions from hydrodynamic-to-elastic coupling simulations

Science.gov (United States)

Chiang, A.; Pitarka, A.; Ford, S. R.; Ezzedine, S. M.; Vorobiev, O.

2017-12-01

A major improvement in ground motion simulation capabilities for underground explosion monitoring during the first phase of the Source Physics Experiment (SPE) is the development of a wave propagation solver that can propagate explosion generated non-linear near field ground motions to the far-field. The calculation is done using a hybrid modeling approach with a one-way hydrodynamic-to-elastic coupling in three dimensions where near-field motions are computed using GEODYN-L, a Lagrangian hydrodynamics code, and then passed to WPP, an elastic finite-difference code for seismic waveform modeling. The advancement in ground motion simulation capabilities gives us the opportunity to assess moment tensor inversion of a realistic volumetric source with near-field effects in a controlled setting, where we can evaluate the recovered source properties as a function of modeling parameters (i.e. velocity model) and can provide insights into previous source studies on SPE Phase I chemical shots and other historical nuclear explosions. For example the moment tensor inversion of far-field SPE seismic data demonstrated while vertical motions are well-modeled using existing velocity models large misfits still persist in predicting tangential shear wave motions from explosions. One possible explanation we can explore is errors and uncertainties from the underlying Earth model. Here we investigate the recovered moment tensor solution, particularly on the non-volumetric component, by inverting far-field ground motions simulated from physics-based explosion source models in fractured material, where the physics-based source models are based on the modeling of SPE-4P, SPE-5 and SPE-6 near-field data. The hybrid modeling approach provides new prospects in modeling explosion source and understanding the uncertainties associated with it.

Optical detection of explosives: spectral signatures for the explosive bouquet

Science.gov (United States)

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

2009-05-01

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

"I Just bought my residents iPads… now what?" The integration of mobile devices into radiology resident education.

Science.gov (United States)

Bedi, Harprit S; Yucel, Edgar K

2013-10-01

This article describes how mobile technologies can improve the way we teach radiology and offers ideas to bridge the clinical gap with technology. Radiology programs across the country are purchasing iPads and other mobile devices for their residents. Many programs, however, do not have a concrete vision for how a mobile device can enhance the learning environment.

The control and prevention of dust explosions

Energy Technology Data Exchange (ETDEWEB)

1982-01-01

Papers presented discussed: explosion characteristics and hybrid mixtures explosion characteristics and influencing factors, propagation of dust explosions in ducts, prevention of dust explosions, desensitization, explosion-proof type of construction, explosion pressure relief, optical flame barriers, slide-valves for explosion protection, Ventex explosion barrier valves, grinding and mixing plants, spray driers, dust explosions in silos, and explosion-proof bucket elevators. One paper has been abstracted separately.

An assessment of potential risk resulting from a maximum credible accident scenario at the proposed explosive waste storage facility (EWSF)

International Nuclear Information System (INIS)

Otsuki, K.; Harrach, R.; Berger, R.

1992-10-01

Lawrence Livermore National Laboratory (LLNL) proposes to build, permit, and operate a storage facility for explosive wastes at LLNL's Explosive Test Site, Site 300. The facility would consist of four existing magazines, four new magazettes (small concrete vaults), and a new prefabricated metal building. Ash from on-site treatment of explosive waste would also be stored in the prefabricated metal building prior to sampling analysis, and shipment. The magazettes would be installed at each magazine-and would provide segregated storage for explosive waste types including detonators, actuators, and other initiating devices. The proposed facility would be used to store explosive wastes generated by the Hydrotest and Explosive Development Programs at LLNL prior to treatment on-site or shipment to permitted, commercial, off-site treatment facilities. Explosive wastes to be stored in the proposed facility represent a full spectrum of Department of Energy (DOE) and LLNL explosive wastes. This document identifies and evaluates the risk to human health and the environment associated with the operation of the proposed EWSF

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.

Development of a calibration system for airborne "1"3"1I monitoring devices

International Nuclear Information System (INIS)

Zhao, C.; Tang, F.; He, L.; Xu, Y.; Lu, X.

2016-01-01

A prototype calibration system for airborne "1"3"1I monitoring devices was developed at the Shanghai Institute of Measurement and Testing Technology (SIMT). This system consists of a gaseous "1"3"1I_2 generator, an airborne storage chamber, an airborne iodine sampler, and an HPGe spectrometer. With this system, "1"3"1I reference samples in the form of charcoal filters and charcoal cartridges, with activities ranging from 100 to 10,000 Bq, were produced with overall relative standard uncertainties of 2.8% (for filter samples) and 3.5% (for cartridge samples); the activities range could be extended according to need. - Highlights: • Original calibration system for airborne "1"3"1I monitoring devices was developed. • Two types of "1"3"1I reference samples was prepared. • The activity of the produced "1"3"1I reference sample could be easily controlled. • The influence of uneven distribution of "1"3"1I in cartridge samples was considered.

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.

Chernobyl explosion bombshell

International Nuclear Information System (INIS)

Martin, S.; Arnott, D.

1988-01-01

It is suggested that the explosion at the Chernobyl-4 reactor in April 1986 was a nuclear explosion. The evidence for this is examined. The sequence of events at Chernobyl is looked at to see if the effects were like those from a nuclear explosion. The question of whether a United Kingdom reactor could go prompt critical is discussed. It is concluded that prompt criticality excursions are possible, but the specific Chernobyl sequence is impossible. (UK)

EEC-sponsored theoretical studies of gas cloud explosion pressure loadings

International Nuclear Information System (INIS)

Briscoe, F.; Curtress, N.; Farmer, C.L.; Fogg, G.J.; Vaughan, G.J.

1979-01-01

Estimates of the pressure loadings produced by unconfined gas cloud explosions on the surface of structures are required to assist the design of strong secondary containments in countries where the protection of nuclear installations against these events is considered to be necessary. At the present time, one difficulty in the specification of occurate pressure loadings arises from our lack of knowledge concerning the interaction between the incident pressure waves produced by unconfined gas cloud explosions and large structures. Preliminary theoretical studies include (i) general theoretical considerations, especially with regard to scaling (ii) investigations of the deflagration wave interaction with a wall based on an analytic solution for situations with planar symmetry and the application of an SRD gas cloud explosion code (GASEX 1) for situations with planar and spherical symmetry, and (iii) investigations of the interaction between shock waves and structures for situations with two-dimensional symmetry based on the application of another SRD gas cloud explosion code (GASEX 2)

Design and validation of inert homemade explosive simulants for ground penetrating radar

Science.gov (United States)

VanderGaast, Brian W.; McFee, John E.; Russell, Kevin L.; Faust, Anthony A.

2015-05-01

The Canadian Armed Forces (CAF) identified a requirement for inert simulants to act as improvised, or homemade, explosives (IEs) when training on, or evaluating, ground penetrating radar (GPR) systems commonly used in the detection of buried landmines and improvised explosive devices (IEDs). In response, Defence R and D Canada (DRDC) initiated a project to develop IE simulant formulations using commonly available inert materials. These simulants are intended to approximate the expected GPR response of common ammonium nitrate-based IEs, in particular ammonium nitrate/fuel oil (ANFO) and ammonium nitrate/aluminum (ANAl). The complex permittivity over the range of electromagnetic frequencies relevant to standard GPR systems was measured for bulk quantities of these three IEs that had been fabricated at DRDC Suffield Research Centre. Following these measurements, published literature was examined to find benign materials with both a similar complex permittivity, as well as other physical properties deemed desirable - such as low-toxicity, thermal stability, and commercial availability - in order to select candidates for subsequent simulant formulation. Suitable simulant formulations were identified for ANFO, with resulting complex permittivities measured to be within acceptable limits of target values. These IE formulations will now undergo end-user trials with CAF operators in order to confirm their utility. Investigations into ANAl simulants continues. This progress report outlines the development program, simulant design, and current validation results.

33 CFR 159.123 - Coliform test: Type I devices.

Science.gov (United States)

2010-07-01

... as follows: During each of the 10-test days, one sample must be taken at the beginning, middle, and end of an 8-consecutive hour period with one additional sample taken immediately following the peak...: Type I devices. (a) The arithmetic mean of the fecal coliform bacteria in 38 of 40 samples of effluent...

A study on vapor explosions

International Nuclear Information System (INIS)

Takagi, N.; Shoji, M.

1979-01-01

An experimental study was carried out for vapor explosions of molten tin falling in water. For various initial metal temperatures and subcooling of water, transient pressure of the explosions, relative frequency of the explosions and the position where the explosions occur were measured in detail. The influence of ambient pressure was also investigated. From the results, it was concluded that the vapor explosion is closely related to the collapse of a vapor film around the molten metal. (author)

Automation in airport security X-ray screening of cabin baggage: Examining benefits and possible implementations of automated explosives detection.

Science.gov (United States)

Hättenschwiler, Nicole; Sterchi, Yanik; Mendes, Marcia; Schwaninger, Adrian

2018-10-01

Bomb attacks on civil aviation make detecting improvised explosive devices and explosive material in passenger baggage a major concern. In the last few years, explosive detection systems for cabin baggage screening (EDSCB) have become available. Although used by a number of airports, most countries have not yet implemented these systems on a wide scale. We investigated the benefits of EDSCB with two different levels of automation currently being discussed by regulators and airport operators: automation as a diagnostic aid with an on-screen alarm resolution by the airport security officer (screener) or EDSCB with an automated decision by the machine. The two experiments reported here tested and compared both scenarios and a condition without automation as baseline. Participants were screeners at two international airports who differed in both years of work experience and familiarity with automation aids. Results showed that experienced screeners were good at detecting improvised explosive devices even without EDSCB. EDSCB increased only their detection of bare explosives. In contrast, screeners with less experience (tenure automated decision provided better human-machine detection performance than on-screen alarm resolution and no automation. This came at the cost of slightly higher false alarm rates on the human-machine system level, which would still be acceptable from an operational point of view. Results indicate that a wide-scale implementation of EDSCB would increase the detection of explosives in passenger bags and automated decision instead of automation as diagnostic aid with on screen alarm resolution should be considered. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Development of steam explosion simulation code JASMINE

Energy Technology Data Exchange (ETDEWEB)

Moriyama, Kiyofumi; Yamano, Norihiro; Maruyama, Yu; Kudo, Tamotsu; Sugimoto, Jun [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Nagano, Katsuhiro; Araki, Kazuhiro

1995-11-01

A steam explosion is considered as a phenomenon which possibly threatens the integrity of the containment vessel of a nuclear power plant in a severe accident condition. A numerical calculation code JASMINE (JAeri Simulator for Multiphase INteraction and Explosion) purposed to simulate the whole process of steam explosions has been developed. The premixing model is based on a multiphase flow simulation code MISTRAL by Fuji Research Institute Co. In JASMINE code, the constitutive equations and the flow regime map are modified for the simulation of premixing related phenomena. The numerical solution method of the original code is succeeded, i.e. the basic equations are discretized semi-implicitly, BCGSTAB method is used for the matrix solver to improve the stability and convergence, also TVD scheme is applied to capture a steep phase distribution accurately. Test calculations have been performed for the conditions correspond to the experiments by Gilbertson et al. and Angelini et al. in which mixing of solid particles and water were observed in iso-thermal condition and with boiling, respectively. (author).

Development of steam explosion simulation code JASMINE

International Nuclear Information System (INIS)

Moriyama, Kiyofumi; Yamano, Norihiro; Maruyama, Yu; Kudo, Tamotsu; Sugimoto, Jun; Nagano, Katsuhiro; Araki, Kazuhiro.

1995-11-01

A steam explosion is considered as a phenomenon which possibly threatens the integrity of the containment vessel of a nuclear power plant in a severe accident condition. A numerical calculation code JASMINE (JAeri Simulator for Multiphase INteraction and Explosion) purposed to simulate the whole process of steam explosions has been developed. The premixing model is based on a multiphase flow simulation code MISTRAL by Fuji Research Institute Co. In JASMINE code, the constitutive equations and the flow regime map are modified for the simulation of premixing related phenomena. The numerical solution method of the original code is succeeded, i.e. the basic equations are discretized semi-implicitly, BCGSTAB method is used for the matrix solver to improve the stability and convergence, also TVD scheme is applied to capture a steep phase distribution accurately. Test calculations have been performed for the conditions correspond to the experiments by Gilbertson et al. and Angelini et al. in which mixing of solid particles and water were observed in iso-thermal condition and with boiling, respectively. (author)

A cost-benefit analysis of alternative device configurations for aviation-checked baggage security screening.

Science.gov (United States)

Jacobson, Sheldon H; Karnani, Tamana; Kobza, John E; Ritchie, Lynsey

2006-04-01

The terrorist attacks of September 11, 2001 have resulted in dramatic changes in aviation security. As of early 2003, an estimated 1,100 explosive detection systems (EDS) and 6,000 explosive trace detection machines (ETD) have been deployed to ensure 100% checked baggage screening at all commercial airports throughout the United States. The prohibitive costs associated with deploying and operating such devices is a serious issue for the Transportation Security Administration. This article evaluates the cost effectiveness of the explosive detection technologies currently deployed to screen checked baggage as well as new technologies that could be used in the future. Both single-device and two-device systems are considered. In particular, the expected annual direct cost of using these devices for 100% checked baggage screening under various scenarios is obtained and the tradeoffs between using single- and two-device strategies are studied. The expected number of successful threats under the different checked baggage screening scenarios with 100% checked baggage screening is also obtained. Lastly, a risk-based screening strategy proposed in the literature is analyzed. The results reported suggest that for the existing security setup, with current device costs and probability parameters, single-device systems are less costly and have fewer expected number of successful threats than two-device systems due to the way the second device affects the alarm or clear decision. The risk-based approach is found to have the potential to significantly improve security. The cost model introduced provides an effective tool for the execution of cost-benefit analyses of alternative device configurations for aviation-checked baggage security screening.

Aspects regarding explosion risk assessment

Directory of Open Access Journals (Sweden)

Părăian Mihaela

2017-01-01

Full Text Available Explosive risk occurs in all activities involving flammable substances in the form of gases, vapors, mists or dusts which, in mixture with air, can generate an explosive atmosphere. As explosions can cause human losses and huge material damage, the assessment of the explosion risk and the establishment of appropriate measures to reduce it to acceptable levels according to the standards and standards in force is of particular importance for the safety and health of people and goods.There is no yet a recognized method of assessing the explosion risk, but regardless of the applied method, the likelihood of an explosive atmosphere occurrence has to be determined, together with the occurrence of an efficient ignition source and the magnitude of foreseeable consequences. In assessment processes, consequences analysis has a secondary importance since it’s likely that explosions would always involve considerable damage, starting from important material damages and up to human damages that could lead to death.The purpose of the work is to highlight the important principles and elements to be taken into account for a specific risk assessment. An essential element in assessing the risk of explosion in workplaces where explosive atmospheres may occur is technical installations and personal protective equipment (PPE that must be designed, manufactured, installed and maintained so that they cannot generate a source of ignition. Explosion prevention and protection requirements are governed by specific norms and standards, and a main part of the explosion risk assessment is related to the assessment of the compliance of the equipment / installation with these requirements.

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...

The dynamic behaviour of the floor of a surrogate vehicle under explosive blast loading

CSIR Research Space (South Africa)

Newell, N

2016-01-01

Full Text Available Improvised Explosive Devices have been the signature weapon in the recent conflicts in Iraq and Afghanistan. High-rate axial forces exerted by the vehicle floor to the lower limbs of occupants have been the cause of severe injuries. In order to gain...

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.

Measurements and standards for bulk-explosives detection

Energy Technology Data Exchange (ETDEWEB)

Hudson, Larry, E-mail: larry.hudson@nist.gov [National Institute of Standards and Technology, 100 Bureau Drive, Stop 8460, Gaithersburg, MD 20899 (United States); Bateman, Fred; Bergstrom, Paul; Cerra, Frank; Glover, Jack; Minniti, Ronaldo; Seltzer, Stephen; Tosh, Ronald [National Institute of Standards and Technology, 100 Bureau Drive, Stop 8460, Gaithersburg, MD 20899 (United States)

2012-07-15

Recent years have seen a dramatic expansion in the application of radiation and isotopes to security screening. This has been driven primarily by increased incidents involving improvised explosive devices as well as their ease of assembly and leveraged disruption of transportation and commerce. With global expenditures for security-screening systems in the hundreds of billions of dollars, there is a pressing need to develop, apply, and harmonize standards for x-ray and gamma-ray screening systems used to detect explosives and other contraband. The National Institute of Standards and Technology has been facilitating the development of standard measurement tools that can be used to gauge the technical performance (imaging quality) and radiation safety of systems used to screen luggage, persons, vehicles, cargo, and left-behind objects. After a review of this new suite of national standard test methods, test objects, and radiation-measurement protocols, we highlight some of the technical trends that are enhancing the revision of baseline standards. Finally we advocate a more intentional use of technical-performance standards by security stakeholders and outline the advantages this would accrue. - Highlights: Black-Right-Pointing-Pointer This work responds to the need for standards for x-ray screening systems used to detect explosives. Black-Right-Pointing-Pointer Described are new measurement tools to gage the performance and radiation safety of such systems. Black-Right-Pointing-Pointer A more intentional use of technical-performance standards by security stakeholders is argued.

Measurements and standards for bulk-explosives detection

International Nuclear Information System (INIS)

Hudson, Larry; Bateman, Fred; Bergstrom, Paul; Cerra, Frank; Glover, Jack; Minniti, Ronaldo; Seltzer, Stephen; Tosh, Ronald

2012-01-01

Recent years have seen a dramatic expansion in the application of radiation and isotopes to security screening. This has been driven primarily by increased incidents involving improvised explosive devices as well as their ease of assembly and leveraged disruption of transportation and commerce. With global expenditures for security-screening systems in the hundreds of billions of dollars, there is a pressing need to develop, apply, and harmonize standards for x-ray and gamma-ray screening systems used to detect explosives and other contraband. The National Institute of Standards and Technology has been facilitating the development of standard measurement tools that can be used to gauge the technical performance (imaging quality) and radiation safety of systems used to screen luggage, persons, vehicles, cargo, and left-behind objects. After a review of this new suite of national standard test methods, test objects, and radiation-measurement protocols, we highlight some of the technical trends that are enhancing the revision of baseline standards. Finally we advocate a more intentional use of technical-performance standards by security stakeholders and outline the advantages this would accrue. - Highlights: ► This work responds to the need for standards for x-ray screening systems used to detect explosives. ► Described are new measurement tools to gage the performance and radiation safety of such systems. ► A more intentional use of technical-performance standards by security stakeholders is argued.

Explosive double salts and preparation

Science.gov (United States)

Cady, Howard H.; Lee, Kien-yin

1984-01-01

Applicants have discovered a new composition of matter which is an explosive addition compound of ammonium nitrate (AN) and diethylenetriamine trinitrate (DETN) in a 50:50 molar ratio. The compound is stable over extended periods of time only at temperatures higher than 46.degree. C., decomposing to a fine-grained eutectic mixture (which is also believed to be new) of AN and DETN at temperatures lower than 46.degree. C. The compound of the invention has an x-ray density of 1.61 g/cm.sup.3, explodes to form essentially only gaseous products, has higher detonation properties (i.e., detonation velocity and pressure) than those of any mechanical mixture having the same density and composition as the compound of the invention, is a quite insensitive explosive material, can be cast at temperatures attainable by high pressure steam, and is prepared from inexpensive ingredients. Methods of preparing the compound of the invention and the fine-grained eutectic composition of the invention are given.

Cutting of CO2 primary circuit pipes of G 2/G 3 using explosive charges

International Nuclear Information System (INIS)

Imbard, G.; Le Goaller, C.; Ravera, J.P.; Bonnier, Y.; Guilbert, J.P.; Puntous, R.

1994-01-01

The objective of this work is to cut large diameter contaminated pipes from the CO 2 cooling system of the gas-cooled reactors by means of explosive charges and to use the resulting shock wave to remove part of the contamination fixed inside the pipe. Two types of tests have been conducted using different explosives in different forms (the decontamination and the cutting tests) and are described. After testing the cutting modules and decontamination fuses, the effects of the detonations on the environment have been measured and were greater than expected. A metal containment device was therefore designed to absorb part of the energy dissipated by the shock wave and retain the debris from the explosions. A description of the tests conducted for this purpose is given. (O.L.). 7 figs., 3 tabs

Explosive magnetorotational instability in Keplerian disks

Energy Technology Data Exchange (ETDEWEB)

Shtemler, Yu., E-mail: shtemler@bgu.ac.il; Liverts, E., E-mail: eliverts@bgu.ac.il; Mond, M., E-mail: mond@bgu.ac.il [Department of Mechanical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel)

2016-06-15

Differentially rotating disks under the effect of axial magnetic field are prone to a nonlinear explosive magnetorotational instability (EMRI). The dynamic equations that govern the temporal evolution of the amplitudes of three weakly detuned resonantly interacting modes are derived. As distinct from exponential growth in the strict resonance triads, EMRI occurs due to the resonant interactions of an MRI mode with stable Alfvén–Coriolis and magnetosonic modes. Numerical solutions of the dynamic equations for amplitudes of a triad indicate that two types of perturbations behavior can be excited for resonance conditions: (i) EMRI which leads to infinite values of the three amplitudes within a finite time, and (ii) bounded irregular oscillations of all three amplitudes. Asymptotic explicit solutions of the dynamic equations are obtained for EMRI regimes and are shown to match the numerical solutions near the explosion time.

[Protecting Safety During Dust Fires and Dust Explosions - The Example of the Formosa Fun Coast Water Park Accident].

Science.gov (United States)

Hsieh, Ming-Hong; Wu, Jia-Wun; Li, Ya-Cing; Tang, Jia-Suei; Hsieh, Chun-Chien

2016-02-01

This paper will explore the fire and explosion characteristics of cornstarch powder as well as strategies for protecting the safety of people who are involved a dust fire or dust explosion. We discuss the 5 elements of dust explosions and conduct tests to analyze the fire and explosion characteristics of differently colored powders (yellow, golden yellow, pink, purple, orange and green). The results show that, while all of the tested powders were difficult to ignite, low moisture content was associated with significantly greater risks of ignition and flame spread. We found the auto-ignition temperature (AIT) of air-borne cornstarch powder to be between 385°C and 405°C, with yellow-colored cornstarch powder showing the highest AIT and pink-colored cornstarch powder showing the lowest AIT. The volume resistivity of all powder samples was approximately 108 Ω.m, indicating that they were nonconductive. Lighters and cigarettes are effective ignition sources, as their lit temperatures are higher than the AIT of cornstarch powder. In order to better protect the safety of individuals at venues where cornstarch powder is released, explosion control measures such as explosion containment facilities, vents, and explosion suppression and isolation devices should be installed. Furthermore, employees that work at these venues should be better trained in explosion prevention and control measures. We hope this article is a reminder to the public to recognize the fire and explosion characteristics of flammable powders as well as the preventive and control measures for dust explosions.

Explosive hazards analysis of the eutectic solution NaK and KO2

International Nuclear Information System (INIS)

Commander, J.C.

1975-06-01

Planning, preparation, conductance, and evaluation of field tests are reported to determine the explosive hazards associated with the combining of the sodium-potassium eutectic alloy (NaK) with the superoxide of potassium (KO 2 ) under various conditions of state, contamination, and detonation initiation. The planning and preparation was conducted by Aerojet Nuclear Company (ANC) at the Idaho National Engineering Laboratory, and the explosive hazards testing was done by Cook Associates, Inc., at IRECO Chemicals Pelican Point Research and Development facility in Utah. The test results showed that binary combinations of pure NaK and KO 2 could not be made to detonate, although the mixtures will spontaneously ignite and burn. However, tertiary combinations of NaK, KO 2 plus a water or hydrocarbon contaminant produced explosive hazards under a variety of conditions. The work was performed as part of the Decontamination and Decommissioning (D and D) of the first Experimental Breeder Reactor (EBR-I) and was funded by 189c I-215. (U.S.)

Non-destructive visualization of linear explosive-induced Pyroshock using phase arrayed laser-induced shock in a space launcher composite

International Nuclear Information System (INIS)

Jang, Jae Kyeong; Lee, Jung Ryul

2015-01-01

Separation mechanism of Space launch vehicles are used in various separation systems and pyrotechnic devices. The operation of these pyrotechnic devices generates Pyroshock that can cause failures in electronic components. The prediction of high frequency structural response, especially the shock response spectrum (SRS), is important. This paper presents a non-destructive visualization and simulation of linear explosive-induced Pyroshock using phase arrayed Laser-induced shock. The proposed method includes a laser shock test based on laser beam and filtering zone conditioning to predict the SRS of Pyroshock. A ballistic test based on linear explosive and non-contact Laser Doppler Vibrometers and a nondestructive Laser shock measurement using laser excitation and several PZT sensors, are performed using a carbon composite sandwich panel. The similarity of the SRS of the conditioned laser shock to that of the real explosive Pyroshock is evaluated with the Mean Acceleration Difference. The average of MADs over the two training points was 33.64%. And, MAD at verification point was improved to 31.99%. After that, experimentally found optimal conditions are applied to any arbitrary points in laser scanning area. Finally, it is shown that linear explosive-induced real Pyroshock wave propagation can be visualized with high similarity based on the proposed laser technology. (paper)

Design and construction of an explosive detection system by Tna methods, using 252Cf radioisotope source

International Nuclear Information System (INIS)

Tavakkoli Farsouli, A.

1999-01-01

Bombs concealed in luggage have threatened human life and property throughout the world's traffic. The plastic explosives could not checked by the X-ray detecting device. Thermal Neutron Activation method has been tested in the present work for non-destructive detection of explosives. A radioisotope neutron source 252 Cf and two gamma spectroscopy systems have been used as a tool to find explosives, regardless of the bomb's shape and the packing materials. The MCNP code has been used to design the neutronic section of the system. The measured thermal neutron fluxes by the gold foils in some location of the system were in good agreement with those data obtained by the MCNP code. Also, detection limits for nitrogen in various counting times were measured. The measurements show that the system is capable to detect 417 gr of HMX explosive material (158 gr nitrogen) by 10 minutes of counting time. To modify the system and to decrease the detection limits some opinions are given

General phenomenology of underground nuclear explosions

International Nuclear Information System (INIS)

Derlich, S.; Supiot, F.

1969-01-01

An essentially qualitatively description is given of the phenomena related to underground nuclear explosions (explosion of a single unit, of several units in line, and simultaneous explosions). In the first chapter are described the phenomena which are common to contained explosions and to explosions forming craters (formation and propagation of a shock-wave causing the vaporization, the fusion and the fracturing of the medium). The second chapter describes the phenomena related to contained explosions (formation of a cavity with a chimney). The third chapter is devoted to the phenomenology of test explosions which form a crater; it describes in particular the mechanism of formation and the different types of craters as a function of the depth of the explosion and of the nature of the ground. The aerial phenomena connected with explosions which form a crater: shock wave in the air and focussing at a large distance, and dust clouds, are also dealt with. (authors) [fr

AND EXPLOSIVE STRENGTH OF YOUNG GYMNASTS

Directory of Open Access Journals (Sweden)

G. Dallas

2014-08-01

Full Text Available The purpose of this study was to examine the acute effect of a single bout of whole body vibration (WBV on flexibility and explosive strength of lower limbs in young artistic gymnasts. Thirty-two young competitive gymnasts volunteered to participate in this study, and were allocated to either the vibration group or traditional body weight training according to the vibration protocol. The vibration intervention consisted of a single bout of eccentric and concentric squatting movements on a vibration platform that was turned on (vibration group: VG n=15, whereas the traditional body weight (no vibration group performed the same training protocol with the WBV device turned off (NVG: n= 17. Flexibility (sit and reach test and explosive strength tests [squat jump (SJ, counter movement jump (CMJ, and single leg squat (right leg (RL and left leg (LL] were performed initially (pre-test, immediately after the intervention (post-test 1, and 15 minutes after the end of the intervention programme (post-test 15. Four 2x3 ANOVAs were used to examine the interaction between group (VG vs NVG and time (pre, post 1, and post 15 with respect to examined variables. The results revealed that a significant interaction between group and time was found with respect to SJ (p 0.05. Further, the percentage improvement of the VG was significantly greater in all examined variables compared to the NVG. This study concluded that WBV training improves flexibility and explosive strength of lower limbs in young trained artistic gymnasts and maintains the initial level of performance for at least 15 minutes after the WBV intervention programme.

Sensitivities of ionic explosives

Science.gov (United States)

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

2017-03-01

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

An Impaled Potential Unexploded Device in the Civilian Trauma Setting: A Case Report and Review of the Literature.

Science.gov (United States)

Thaut, Lane C; Murtha, Andrew S; Johnson, Anthony E; Roper, Jamie L

2018-05-01

The management of patients with impaled unexploded devices is rare in the civilian setting. However, as the lines of the traditional battlefield are blurred by modern warfare and terrorist activity, emergency providers should be familiar with facility protocols, plans, and contact information of their local resources for unexploded devices. A 44-year-old male sustained a close-proximity blast injury to his lower extremities while manipulating a mortar-type firework. He presented to the regional trauma center with an open, comminuted distal femur fracture and radiographic evidence of a potential explosive device in his thigh. His management was coordinated with the local Explosive Ordinance Disposal and the fire department. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Explosive devices pose a grave threat when encountered. Familiarization with protocols to manage these patients can mitigate disaster. Emergency providers should expect and be prepared to coordinate care for these patients. Copyright © 2017 Elsevier Inc. All rights reserved.

An experimental study of an explosively driven flat plate launcher

Science.gov (United States)

Rae, Philip; Haroz, Erik; Armstrong, Chris; Perry, Lee; M Division Team

2017-06-01

For some upcoming experiments it is desired to impact a large explosive assembly with one or more moderate diameter flat metal plates traveling at high velocity (2-3 km s-1). The time of arrival of these plates will need to carefully controlled and delayed (i.e. the time(s) of arrival known to approximately a microsecond). For this reason, producing a flyer plate from more traditional gun assemblies is not possible. Previous researchers have demonstrated the ability to throw reasonably flat metal flyers from the so-called Forest flyer geometry. The defining characteristics of this design are a carefully controlled reduction in explosive area from a larger explosive plane-wave-lens and booster pad to a smaller flyer plate to improve the planarity of the drive available and an air gap between the explosive booster and the plate to reduce the peak tensile stresses generated in the plate to suppress spalling. This experimental series comprised a number of different design variants and plate and explosive drive materials. The aim was to calibrate a predictive computational modeling capability on this kind of system in preparation for later more radical design ideas best tested in a computer before undertaking the expensive business of construction.

Peaceful nuclear explosions

Energy Technology Data Exchange (ETDEWEB)

NONE

1975-07-01

Article V of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) specifies that the potential benefits of peaceful applications of nuclear explosions be made available to non-nuclear weapon states party to the Treaty 'under appropriate international observation and through appropriate international procedures'. The International Atomic Energy Agency's responsibility and technical competence in this respect have been recognized by its Board of Governors, the Agency's General Conference and the United Nations' General Assembly. Since 1968 when the United Nations Conference of Non-Nuclear Weapon States also recommended that the Agency initiate the necessary studies in the peaceful nuclear explosions (PNE) field, the Agency has taken the following steps: 1. The exchange of scientific and technical information has been facilitated by circulating information on the status of the technology and through the Agency's International Nuclear Information System. A bibliography of PNE-related literature was published in 1970. 2. In 1972, guidelines for 'the international observation of PNE under the provisions of NPT and analogous provisions in other international agreements' were developed and approved by the Board of Governors. These guidelines defined the basic purpose of international observation as being to verify that in the course of conducting a PNE project the intent and letter of Articles I and II of the NPT are not violated. 3. In 1974, an advisory group developed 'Procedures for the Agency to Use in Responding to Requests for PNE-Related Services'. These procedures have also been approved by the Board of Governors. 4. The Agency has convened a series of technical meetings which reviewed the 'state-of-the- art'. These meetings were convened in 1970, 1971, 1972 and in January 1975. The Fourth Technical Committee was held in Vienna from 20-24 January 1975 under the chairmanship of Dr. Allen Wilson of Australia with Experts from: Australia, France, Federal

iConnected use AirPlay, iCloud, apps, and more to bring your Apple devices together

CERN Document Server

Harvell, Ben

2013-01-01

Bring your Apple products together and enjoy an orchard of intelligent, unified technology! Whether at work or at home, syncing multiple Apple devices can help you achieve an organized, streamlined, harmonized life. With this unique resource, you discover how to get the most out of AirPlay and iCloud, Apple's streaming and cloud services. Featuring a four-color design and packed with helpful codes, tips, and tricks, this accessible book shows you how to write a document on an iMac at home and then continue editing it on an iPad while on the go without worrying about synching the de

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.

Book Review: iPhone and iOS Forensic: Investigation, Analysis and Mobile Security for Apple iPhone, iPad and iOS Devices

Directory of Open Access Journals (Sweden)

Simson Garfinkel

2013-12-01

Full Text Available Hoog, A., and Strzempka, K. (2011.  iPhone and iOS Forensic: Investigation, Analysis and Mobile Security for Apple iPhone, iPad and iOS Devices. Syngress, Elsevier, xv + 310 pages; ISBN-10: 1597496596; ISBN-13: 978-1597496599, $69.95Reviewed by Simson Garfinkel, Naval Postgraduate SchoolIn April 2011 news outlets around the world revealed shocking news about Apple’s iPhone: for reasons that were not apparently clear, every iPhone contained a small SQLite database that logged where and when the user had been whenever the phone was turned on, and those records went back for pretty much as long as the user had owned their phone. Apple eventually declared that the data cache was the result of a bug and issued a software update to prune the database (it had previously grown without limit. Privacy activists rejoiced that their beloved iPhones were once again trustworthy. But forensics examiners just shook their heads: many had known about the iPhone’s tracking capabilities for more than a year and had kept quiet. They had made good use of that data. Apple’s pro-privacy patch was actually a setback for law enforcement.(see PDF for full review

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

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

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 ...

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.

Radiological dispersal device outdoor simulation test: Cesium chloride particle characteristics

Energy Technology Data Exchange (ETDEWEB)

Lee, Sang Don, E-mail: lee.sangdon@epa.gov [U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Snyder, Emily G.; Willis, Robert [U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Fischer, Robert; Gates-Anderson, Dianne; Sutton, Mark [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Viani, Brian [Simbol Mining Corp., Pleasanton, CA 94566 (United States); Drake, John [U.S. Environmental Protection Agency, Cincinnati, OH 45268 (United States); MacKinney, John [U.S. Department of Homeland Security, Washington, DC 20528 (United States)

2010-04-15

Particles were generated from the detonation of simulated radiological dispersal devices (RDDs) using non-radioactive CsCl powder and explosive C4. The physical and chemical properties of the resulting particles were characterized. Two RDD simulation tests were conducted at Lawrence Livermore National Laboratory: one of the simulated RDDs was positioned 1 m above a steel plate and the other was partially buried in soil. Particles were collected with filters at a distance of 150 m from the origin of the RDD device, and particle mass concentrations were monitored to identify the particle plume intensity using real time particle samplers. Particles collected on filters were analyzed via computer-controlled scanning electron microscopy coupled with energy dispersive X-ray spectrometry (CCSEM/EDX) to determine their size distribution, morphology, and chemical constituents. This analysis showed that particles generated by the detonation of explosives can be associated with other materials (e.g., soil) that are in close proximity to the RDD device and that the morphology and chemical makeup of the particles change depending on the interactions of the RDD device with the surrounding materials.

Radiological dispersal device outdoor simulation test: Cesium chloride particle characteristics

International Nuclear Information System (INIS)

Lee, Sang Don; Snyder, Emily G.; Willis, Robert; Fischer, Robert; Gates-Anderson, Dianne; Sutton, Mark; Viani, Brian; Drake, John; MacKinney, John

2010-01-01

Particles were generated from the detonation of simulated radiological dispersal devices (RDDs) using non-radioactive CsCl powder and explosive C4. The physical and chemical properties of the resulting particles were characterized. Two RDD simulation tests were conducted at Lawrence Livermore National Laboratory: one of the simulated RDDs was positioned 1 m above a steel plate and the other was partially buried in soil. Particles were collected with filters at a distance of 150 m from the origin of the RDD device, and particle mass concentrations were monitored to identify the particle plume intensity using real time particle samplers. Particles collected on filters were analyzed via computer-controlled scanning electron microscopy coupled with energy dispersive X-ray spectrometry (CCSEM/EDX) to determine their size distribution, morphology, and chemical constituents. This analysis showed that particles generated by the detonation of explosives can be associated with other materials (e.g., soil) that are in close proximity to the RDD device and that the morphology and chemical makeup of the particles change depending on the interactions of the RDD device with the surrounding materials.

Free radical explosive composition

Science.gov (United States)

Walker, Franklin E.; Wasley, Richard J.

1979-01-01

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

Nano-powder production by electrical explosion of wires

International Nuclear Information System (INIS)

Mao Zhiguo; Zou Xiaobing; Wang Xinxin; Jiang Weihua

2010-01-01

A device for nano-powder production by electrical explosion of wires was designed and built. Eight wires housed in the discharge chamber are exploded one by one before opening the chamber for the collection of the produced nano-powder. To increase the rate of energy deposition into a wire, the electrical behavior of the discharge circuit including the exploding wire was simulated. The results showed that both reducing the circuit inductance and reducing the capacitance of the energy-storage capacitor (keeping the storage energy constant) can increase the energy deposition rate. To better understand the physical processes of the nano-powder formation by the wire vapor, a Mach-Zehnder interferometer was used to record the time evolution of the wire vapor as well as the plasma. A thermal expansion lag of the dense vapor core as well as more than one times of the vapor burst was observed for the first time. Finally, nano-powders of titanium nitride, titanium dioxide, copper oxides and zinc oxide were produced by electrical explosion of wires. (authors)

Correlations between the disintegration of melt and the measured impulses in steam explosions

Energy Technology Data Exchange (ETDEWEB)

Froehlich, G.; Linca, A.; Schindler, M. [Univ. of Stuttgart (Germany)

1995-09-01

To find our correlations in steam explosions (melt water interactions) between the measured impulses and the disintegration of the melt, experiments were performed in three configurations i.e. stratified, entrapment and jet experiments. Linear correlations were detected between the impulse and the total surface of the fragments. Theoretical considerations point out that a linear correlation assumes superheating of a water layer around the fragments of a constant thickness during the fragmentation process to a constant temperature (here the homogeneous nucleation temperature of water was assumed) and a constant expansion velocity of the steam in the main expansion time. The correlation constant does not depend on melt temperature and trigger pressure, but it depends on the configuration of the experiment or of a scenario of an accident. Further research is required concerning the correlation constant. For analysing steam explosion accidents the explosivity is introduced. The explosivity is a mass specific impulse. The explosivity is linear correlated with the degree of fragmentation. Knowing the degree of fragmentation with proper correlation constant the explosivity can be calculated and from the explosivity combined with the total mass of fragments the impulse is obtained which can be used to an estimation of the maximum force.

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.

High-nitrogen explosives

Energy Technology Data Exchange (ETDEWEB)

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

2002-01-01

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

30 CFR 77.1301 - Explosives; magazines.

Science.gov (United States)

2010-07-01

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

Explosion metal welding

International Nuclear Information System (INIS)

Popoff, A.A.

1976-01-01

Process parameters pertaining to welding similar and dissimilar metals using explosives are reviewed. The discussion centers on the interrelationship of physical parameters which play a part in achieving desirable metallurgical results. Present activities in explosion metal welding at LASL are presented and shown how they related to the interests of the ERDA community

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.

Zirconium hydride containing explosive composition

Science.gov (United States)

Walker, Franklin E.; Wasley, Richard J.

1981-01-01

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

Seismic measurements of explosions in the Tatum Salt Dome, Mississippi

Science.gov (United States)

Borcherdt, Roger D.; Healy, J.H.; Jackson, W.H.; Warren, D.R.

1967-01-01

Project Sterling provided for the detonation of a nuclear device in the cavity resulting from the Salmon nuclear explosion in the Tatum salt dome in southern Mississippi. It also provided for a high explosive (HE) comparison shot in a nearby drill hole. The purpose of the experiment was to gather information on the seismic decoupling of a nuclear explosion in a cavity by comparing seismic signals from a nuclear shot in the Salmon cavity with seismic signals recorded from Salmon and with seismic signals recorded from a muall (about 2 tons) HE shot in the salt dome. Surface seismic measurements were made by the U.S. Geological Survey, the U.S. Coast and Geodetic Survey, and the Air Force Technical Applications Center with coordination and overall direction by the Lawrence Radiation Laboratory. This report covers only the seismic measurements made by the U. S. Geological Survey. The first objective of this report is to describe the field recording procedures and the data obtained by the U. S. Geological Survey from these events. The second objective is to describe the spectral analyses which have been made on the data and the relative seismic amplitudes which have been determined from these analyses.

Experimental and theoretical study of helical explosive electrical current generators with magnetic field compression

International Nuclear Information System (INIS)

Antoni, Bernard; Nazet, Christian.

1975-07-01

A generator of electrical energy in which magnetic field compression is achieved by a solid explosive is described. The magnetic flux losses have been calculated for generators of various configurations by the skin depth concept. Calculations take the Joule heating of conductors into account. In helical generators the magnetic flux losses are higher than those calculated by considering diffusion only. Additional losses approximately as important as diffusion losses have already been observed elsewhere on similar devices. Detailed calculations of the motion of the explosively driven inner conductor show that losses come from the jumps encountered by sliding contact moving along the helix. The jumps are caused by little geometrical defects and the consequence on losses is strongly dependent on current intensity. The jumps decrease when the pitch of helix increases. The jumps are detrimental to the efficient use of the explosive energy. With helical generators only 5% of the energy is transferred into magnetic energy [fr

Using of acoustic technologies for detection of explosives in gas, liquid and solid medium

International Nuclear Information System (INIS)

Valyaev, A. N.; Yanushkevich, V.A.

2004-01-01

contained acoustic radiator and detector, with probe selection of diagnostic material. That is why at first the acoustic passports will be obtained for all types of explosives and their data bank will be formed. This bank will included C (ω,T), α (ω,T) and ρ (ω,T) dependences, which will identify a presence and a specific type of explosive. We propose the universal system, that may be quickly adapted for search and diagnostics of different types of matter, including a qualitative and quantitative analysis of their few main components. This system may be realized in the development of devices, that used the acoustic techniques. The principles of system function is discussed. The practical realization of this method on example of image of alcohol beverage type. The presented 2a and 3D diagrams for system of ethyl alcohol-sugar-water solutions proved the possibilities of our technique for the operative and reliable diagnostic. The similar technique we successfully used in the development and the application of new devices for monitoring and measurements of alcohol and sugar concentrations in industrial flood plains of vodka, brandies, liqueurs, wines and champagnes at Russian plants. The principle advantages and disadvantages of the proposed technique, including the special engineering and design elements of the devices for diagnostic of explosives are under consideration. It is noticed, that this technique may be used for detection of solid and liquid explosives in grounds and in another solid materials, in water and gas mediums and we recommend to use it as the special monitoring method for very important large objects, such as dams of uranium tailing storages in Tyan-Shan Mountains

8. Peaceful uses of nuclear explosions

International Nuclear Information System (INIS)

Musilek, L.

1992-01-01

The chapter deals with peaceful uses of nuclear explosions. Described are the development of the underground nuclear explosion, properties of radionuclides formed during the explosion, their distribution, the release of radioactive products of underground nuclear explosions into the air, their propagation in the atmosphere, and fallout in the landscape. (Z.S.). 1 tab., 8 figs., 19 refs

Interim guidance risk assessment of the device assembly facility at the Nevada test site

International Nuclear Information System (INIS)

Altenbach, T.J.

1996-05-01

The risks of plutonium dispersal and/or high explosive detonation from nuclear explosive operations at the Device Assembly Facility were examined in accordance with DOE Order 5610.11 and the Interim Guidance. The assessment consisted of a qualitative task and hazards analysis, and a quantitative risk screening. Results are displayed on risk matrices for the major types of operations. Most accident scenarios were considered to have Low risk; a few scenarios have Moderate risk; and none have High risk. The highest risk scenarios (Moderate category) consist of a high explosive detonation during assembly operations in a cell, with bare conventional high explosive surrounding the pit

Fundamental characteristics of microwave explosion pretreatment of wood. I, Properties of temperature development

Science.gov (United States)

Xian-jun Li; Ke-yang Lu; Lan-ying Lin; Yong-dong Zhou; Zhi-yong Cai; Feng Fu

2010-01-01

In this study, the effects of microwave radiation intensity, radiation time and initial wood moisture content (MC) on the properties of temperature development in Eucalyptus urophylla wood samples during the microwave explosion pretreatment have been investigated using a new microwave pretreatment equipment. The results show that 1) with the increase of microwave...

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...

Neutrino oscillations in magnetically driven supernova explosions

Energy Technology Data Exchange (ETDEWEB)

Kawagoe, Shio; Kotake, Kei [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan); Takiwaki, Tomoya, E-mail: shio.k@nao.ac.jp, E-mail: takiwaki.tomoya@nao.ac.jp, E-mail: kkotake@th.nao.ac.jp [Center for Computational Astrophysics, National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan)

2009-09-01

We investigate neutrino oscillations from core-collapse supernovae that produce magnetohydrodynamic (MHD) explosions. By calculating numerically the flavor conversion of neutrinos in the highly non-spherical envelope, we study how the explosion anisotropy has impacts on the emergent neutrino spectra through the Mikheyev-Smirnov-Wolfenstein effect. In the case of the inverted mass hierarchy with a relatively large θ{sub 13} (sin{sup 2} 2θ{sub 13} ∼> 10{sup −3}), we show that survival probabilities of ν-bar {sub e} and ν{sub e} seen from the rotational axis of the MHD supernovae (i.e., polar direction), can be significantly different from those along the equatorial direction. The event numbers of ν-bar {sub e} observed from the polar direction are predicted to show steepest decrease, reflecting the passage of the magneto-driven shock to the so-called high-resonance regions. Furthermore we point out that such a shock effect, depending on the original neutrino spectra, appears also for the low-resonance regions, which could lead to a noticeable decrease in the ν{sub e} signals. This reflects a unique nature of the magnetic explosion featuring a very early shock-arrival to the resonance regions, which is in sharp contrast to the neutrino-driven delayed supernova models. Our results suggest that the two features in the ν-bar {sub e} and ν{sub e} signals, if visible to the Super-Kamiokande for a Galactic supernova, could mark an observational signature of the magnetically driven explosions, presumably linked to the formation of magnetars and/or long-duration gamma-ray bursts.

Neutrino oscillations in magnetically driven supernova explosions

Science.gov (United States)

Kawagoe, Shio; Takiwaki, Tomoya; Kotake, Kei

2009-09-01

We investigate neutrino oscillations from core-collapse supernovae that produce magnetohydrodynamic (MHD) explosions. By calculating numerically the flavor conversion of neutrinos in the highly non-spherical envelope, we study how the explosion anisotropy has impacts on the emergent neutrino spectra through the Mikheyev-Smirnov-Wolfenstein effect. In the case of the inverted mass hierarchy with a relatively large θ13 (sin2 2θ13 gtrsim 10-3), we show that survival probabilities of bar nue and νe seen from the rotational axis of the MHD supernovae (i.e., polar direction), can be significantly different from those along the equatorial direction. The event numbers of bar nue observed from the polar direction are predicted to show steepest decrease, reflecting the passage of the magneto-driven shock to the so-called high-resonance regions. Furthermore we point out that such a shock effect, depending on the original neutrino spectra, appears also for the low-resonance regions, which could lead to a noticeable decrease in the νe signals. This reflects a unique nature of the magnetic explosion featuring a very early shock-arrival to the resonance regions, which is in sharp contrast to the neutrino-driven delayed supernova models. Our results suggest that the two features in the bar nue and νe signals, if visible to the Super-Kamiokande for a Galactic supernova, could mark an observational signature of the magnetically driven explosions, presumably linked to the formation of magnetars and/or long-duration gamma-ray bursts.

Nucleosynthesis in stellar explosions

International Nuclear Information System (INIS)

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 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

High-Efficiency, Nanowire Based Thermoelectric Devices for Radioisotope Power Conversion, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — This SBIR Phase I proposal responds to topic S3.03 of the 2010 NASA SBIR solicitation, for Power Generation and Conversion. Thermoelectric devices offer a simple and...

Trace explosives sensor testbed (TESTbed)

Science.gov (United States)

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

2017-03-01

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

Stability and Performance of CsPbI2Br Thin Films and Solar Cell Devices.

Science.gov (United States)

Mariotti, Silvia; Hutter, Oliver S; Phillips, Laurie J; Yates, Peter J; Kundu, Biswajit; Durose, Ken

2018-01-31

In this manuscript, the inorganic perovskite CsPbI 2 Br is investigated as a photovoltaic material that offers higher stability than the organic-inorganic hybrid perovskite materials. It is demonstrated that CsPbI 2 Br does not irreversibly degrade to its component salts as in the case of methylammonium lead iodide but instead is induced (by water vapor) to transform from its metastable brown cubic (1.92 eV band gap) phase to a yellow phase having a higher band gap (2.85 eV). This is easily reversed by heating to 350 °C in a dry environment. Similarly, exposure of unencapsulated photovoltaic devices to water vapor causes current (J SC ) loss as the absorber transforms to its more transparent (yellow) form, but this is also reversible by moderate heating, with over 100% recovery of the original device performance. NMR and thermal analysis show that the high band gap yellow phase does not contain detectable levels of water, implying that water induces the transformation but is not incorporated as a major component. Performances of devices with best efficiencies of 9.08% (V OC = 1.05 V, J SC = 12.7 mA cm -2 and FF = 68.4%) using a device structure comprising glass/ITO/c-TiO 2 /CsPbI 2 Br/Spiro-OMeTAD/Au are presented, and further results demonstrating the dependence of the performance on the preparation temperature of the solution processed CsPbI 2 Br films are shown. We conclude that encapsulation of CsPbI 2 Br to exclude water vapor should be sufficient to stabilize the cubic brown phase, making the material of interest for use in practical PV devices.

Report on the treatability study for inerting small quantities of radioactive explosives and explosive components

International Nuclear Information System (INIS)

Loyola, V.M.; Reber, S.D.

1996-02-01

As a result of Sandia's radiation hardening testing on a variety of its explosive components, radioactive waste streams were generated and have to be disposed of as radioactive waste. Due to the combined hazards of explosives and radioactivity, Sandia's Radioactive and Mixed Waste Management organization did not have a mechanism for disposal of these waste streams. This report documents the study done to provide a method for the removal of the explosive hazard from those waste streams. The report includes the design of the equipment used, procedures followed, results from waste stream analog tests and the results from the actual explosive inerting tests on radioactive samples. As a result of the inerting treatment, the waste streams were rendered non-explosive and, thus, manageable through normal radioactive waste disposal channels

Radioactive gaseous waste processing device

International Nuclear Information System (INIS)

Kawabe, Ken-ichi; Uchiyama, Yoshio; Konno, Masanobu; Suzuki, Kunihiko; Kimura, Tadahiro.

1991-01-01

A main steam bypass line is disposed to a main steam line of an air extractor for directly sending diluting steams to an exhaust gas line disposed upstream of a preheater not by way of the extractor. Then, a hydrogen flowmeter is disposed to a hydrogen injection line of a hydrogen supply device for measuring the amount of hydrogen to be injected. Further, a control means is disposed to the main steam bypass line for controlling the injection of the diluting steams based on a signal from the hydrogen flowmeter. With such a constitution, the amount of the hydrogen gas supplied from the hydrogen supply device is detected by the hydrogen flowmeter. The control means disposed to the main steam bypass line or the control means disposed directly to the main steam line injects the diluting steams to the exhaust gas line based on the signal from the hydrogen flowmeter. This can reduce the hydrogen concentration in the exhaust gas upstream of the pre-heater to less than an explosive limit, to enable a countermeasure for preventing hydrogen explosion upon hydrogen injection. (T.M.)

Scaling laws governing the multiple scattering of diatomic molecules under Coulomb explosion

International Nuclear Information System (INIS)

Sigmund, P.

1992-01-01

The trajectories of fast molecules during and after penetration through foils are governed by Coulomb explosion and distorted by multiple scattering and other penetration phenomena. A scattering event may cause the energy available for Coulomb explosion to increase or decrease, and angular momentum may be transferred to the molecule. Because of continuing Coulomb explosion inside and outside the target foil, the transmission pattern recorded at a detector far away from the target is not just a linear superposition of Coulomb explosion and multiple scattering. The velocity distribution of an initially monochromatic and well-collimated, but randomly oriented, beam of molecular ions is governed by a generalization of the standard Bothe-Landau integral that governs the multiple scattering of atomic ions. Emphasis has been laid on the distribution in relative velocity and, in particular, relative energy. The statistical distributions governing the longitudinal motion (i.e., the relative motion along the molecular axis) and the rotational motion can be scaled into standard multiple-scattering distributions of atomic ions. The two scaling laws are very different. For thin target foils, the significance of rotational energy transfer is enhanced by an order of magnitude compared to switched-off Coulomb explosion. A distribution for the total relative energy (i.e., longitudinal plus rotational motion) has also been found, but its scaling behavior is more complex. Explicit examples given for all three distributions refer to power-law scattering. As a first approximation, scattering events undergone by the two atoms in the molecule were assumed uncorrelated. A separate section has been devoted to an estimate of the effect of impact-parameter correlation on the multiple scattering of penetrating molecules

Standoff laser-induced thermal emission of explosives

Science.gov (United States)

Galán-Freyle, Nataly Y.; Pacheco-Londoño, Leonardo C.; Figueroa-Navedo, Amanda; Hernandez-Rivera, Samuel P.

2013-05-01

A laser mediated methodology for remote thermal excitation of analytes followed by standoff IR detection is proposed. The goal of this study was to determine the feasibility of using laser induced thermal emission (LITE) from vibrationally excited explosives residues deposited on surfaces to detect explosives remotely. Telescope based FT-IR spectral measurements were carried out to examine substrates containing trace amounts of threat compounds used in explosive devices. The highly energetic materials (HEM) used were PETN, TATP, RDX, TNT, DNT and ammonium nitrate with concentrations from 5 to 200 μg/cm2. Target substrates of various thicknesses were remotely heated using a high power CO2 laser, and their mid-infrared (MIR) thermally stimulated emission spectra were recorded. The telescope was configured from reflective optical elements in order to minimize emission losses in the MIR frequencies and to provide optimum overall performance. Spectral replicas were acquired at a distance of 4 m with an FT-IR interferometer at 4 cm- 1 resolution and 10 scans. Laser power was varied from 4-36 W at radiation exposure times of 10, 20, 30 and 60 s. CO2 laser powers were adjusted to improve the detection and identification of the HEM samples. The advantages of increasing the thermal emission were easily observed in the results. Signal intensities were proportional to the thickness of the coated surface (a function of the surface concentration), as well as the laser power and laser exposure time. For samples of RDX and PETN, varying the power and time of induction of the laser, the calculated low limit of detections were 2 and 1 μg/cm2, respectively.

R-22 vapor explosions

International Nuclear Information System (INIS)

Anderson, R.P.; Armstrong, D.R.

1977-01-01

Previous experimental and theoretical studies of R-22 vapor explosions are reviewed. Results from two experimental investigations of vapor explosions in a medium scale R-22/water system are reported. Measurements following the drop of an unrestrained mass of R-22 into a water tank demonstrated the existence of two types of interaction behavior. Release of a constrained mass of R-22 beneath the surface of a water tank improved the visual resolution of the system thus allowing identification of two interaction mechansims: at low water temperatures, R-22/water contact would produce immediate violent boiling; at high water temperatures a vapor film formed around its R-22 as it was released, explosions were generated by a surface wave which initiated at a single location and propagated along the vapor film as a shock wave. A new vapor explosion model is proposed, it suggests explosions are the result of a sequence of three independent steps: an initial mixing phase, a trigger and growth phase, and a mature phase where a propagating shock wave accelerates the two liquids into a collapsing vapor layer causing a high velocity impact which finely fragments and intermixes the two liquids

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.

Augmented communication with haptic I/O in mobile devices

OpenAIRE

Haverinen, Laura

2012-01-01

Nonverbal communication is a very important part of face to face communication. Both explicit and implicit additions to verbal communication augment the information content of communication. Before telephones did not provide any means for adding nonverbal information to the communication, but now, as the technology has advanced, it is possible to start augmenting also the communication on the phone. Adding a haptic I/O device to a regular mobile phone opens possibilities to add value to commu...

Expediency of application of explosion-relief constructions to ensure explosion resistance of production buildings

Directory of Open Access Journals (Sweden)

Lyapin Anton

2016-01-01

Full Text Available The article presents a model of economic evaluation and selection of explosion-relief constructions (ERC, as well as determination of explosion protection efficiency of buildings and structures provided on a stage of construction. It has been shown that definition of economic efficiency of ERС is the evaluation of its application for buildings with remote or automatically controlled production. It has been determined that an important role in design of explosive industrial facilities is played by selection of the economically feasible and effective materials for ERC. When selecting materials it is necessary to consider probability and yield of explosions. Necessity to create the methods allow considering such probability has been revealed.

Explosives 92. Conference proceedings

Energy Technology Data Exchange (ETDEWEB)

Farnfield, R.A. (ed.)

1992-01-01

17 papers are presented. Topics covered include: the POG system - a new concept in the use of ANFO; demolition of a motorway bridge; presplit and smooth blasting; VIBReX - a predictive code for assessing the effect of blast design on ground vibration; ground vibrations from blasting; digital seismographs; human response to blasting and the effects on planning conditions; landform construction by restoration blasting; use of small diameter explosives; efficient priming; safety management in the explosives industry; and the law on packaging of explosives. Two papers have been abstracted separately.

Problems in the theory of point explosions

Science.gov (United States)

Korobeinikov, V. P.

The book is concerned with the development of the theory of point explosions, which is relevant to the study of such phenomena as the initiation of detonation, high-power explosions, electric discharges, cosmic explosions, laser blasts, and hypersonic aerodynamics. The discussion covers the principal equations and the statement of problems; linearized non-self-similar one-dimensional problems; spherical, cylindrical, and plane explosions with allowance for counterpressure under conditions of constant initial density; explosions in a combustible mixture of gases; and point explosions in inhomogeneous media with nonsymmetric energy release. Attention is also given to point explosions in an electrically conducting gas with allowance for the effect of the magnetic field and to the propagation of perturbations from solar flares.

The Magnetar Model of the Superluminous Supernova GAIA16apd and the Explosion Jet Feedback Mechanism

International Nuclear Information System (INIS)

Soker, Noam

2017-01-01

Under the assumption that jets explode core collapse supernovae (CCSNe) in a negative jet feedback mechanism (JFM), this paper shows that rapidly rotating neutron stars are likely to be formed when the explosion is very energetic. Under the assumption that an accretion disk or an accretion belt around the just-formed neutron star launch jets and that the accreted gas spins-up the just-formed neutron star, I derive a crude relation between the energy that is stored in the spinning neutron star and the explosion energy. This relation is ( E _N_S_-_s_p_i_n/ E _e_x_p) ≈ E _e_x_p/10"5"2 erg; It shows that within the frame of the JFM explosion model of CCSNe, spinning neutron stars, such as magnetars, might have significant energy in super-energetic explosions. The existence of magnetars, if confirmed, such as in the recent super-energetic supernova GAIA16apd, further supports the call for a paradigm shift from neutrino-driven to jet-driven CCSN mechanisms.

Safety engineering experiments of explosives

Energy Technology Data Exchange (ETDEWEB)

Ishikawa, Noboru

1987-07-24

The outline of large scale experiments carried out every year since 1969 to obtain fundamental data and then establish the safety engineering standards concerning the manufacturing, storage and transportation, etc. of all explosives was described. Because it becomes recently difficult to ensure the safety distance in powder magazines and powder plants, the sandwich structure with sand is thought to be suitable as the neighboring barrier walls. The special vertical structure for embankments to provide against a emergency explosion is effective to absorb the blast. Explosion behaviors such as initiating sensitivity, detonation, sympathetic detonation, and shock occurence of the ANFO explosives in place of dynamite and the slurry explosives were studied. The safety engineering standards for the manufacturing and application of explosives were studied to establish because accidents by tabacco fire are not still distinguished. Much data concerning early stage fire fighting, a large quantity of flooding and shock occurence from a assumption of ignition during machining in the propellants manufacturing plant, could be obtained. Basic studies were made to prevent pollution in blasting sites. Collected data are utilized for the safety administration after sufficient discussion. (4 figs, 2 tabs, 3 photos, 17 refs)

Sensitivity to friction for primary explosives

International Nuclear Information System (INIS)

Matyáš, Robert; Šelešovský, Jakub; Musil, Tomáš

2012-01-01

Highlights: ► The friction sensitivity of 14 samples of primary explosives was determined. ► The same apparatus (small scale BAM) and the same method (probit analysis) was used. ► The crystal shapes and sizes were documented with microscopy. ► Almost all samples are less sensitive than lead azide, which is commercially used. ► 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.

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.

Explosive eruptions triggered by rockfalls at Kīlauea volcano, Hawaii

Science.gov (United States)

Orr, Tim R.; Thelen, Weston A.; Patrick, Matthew R.; Swanson, Donald A.; Wilson, David C.

2012-01-01

Ongoing eruptive activity at Kīlauea volcano’s (Hawai‘i) summit has been controlled in part by the evolution of its vent from a 35-m-diameter opening into a collapse crater 150 m across. Geologic observations, in particular from a network of webcams, have provided an unprecedented look at collapse crater development, lava lake dynamics, and shallow outgassing processes. These observations show unequivocally that the hundreds of transient outgassing bursts and weak explosive eruptions that have punctuated the vent’s otherwise nearly steady-state behavior, and that are associated with composite seismic events, were triggered by rockfalls from the vent walls onto the top of the lava column. While the process by which rockfalls drive the explosive bursts is not fully understood, we believe that it is initiated by the generation of a rebound splash, or Worthington jet, which then undergoes fragmentation. The external triggering of low-energy outgassing events by rockfalls represents a new class of small transient explosive eruptions.

Field Prototype of the ENEA Neutron Active Interrogation Device for the Detection of Dirty Bombs

Directory of Open Access Journals (Sweden)

Nadia Cherubini

2016-10-01

Full Text Available The Italian National Agency for New Technologies, Energy, and Sustainable Economic Development (ENEA Neutron Active Interrogation (NAI device is a tool designed to improve CBRNE defense. It is designed to uncover radioactive and nuclear threats including those in the form of Improvised Explosive Devices (IEDs, the so-called “dirty bombs”. The NAI device, at its current development stage, allows to detect 6 g of 235U hidden in a package. It is easily transportable, light in weight, and with a real-time response. Its working principle is based on two stages: (1 an “active” stage in which neutrons are emitted by a neutron generator to interact with the item under inspection, and (2 a “passive” stage in which secondary neutrons are detected originating a signal that, once processed, allows recognition of the offence. In particular, a clear indication of the potential threat is obtained by a dedicated software based on the Differential Die-Away Time Analysis method.

Proceedings of the CSNI specialist meeting on interaction of fire and explosion with ventilation systems in nuclear facilities. Volume I

International Nuclear Information System (INIS)

1983-10-01

Separate abstracts were prepared for the papers presented in the following areas: (1) fire and explosion perspectives; (2) fire, explosion, and radioactive source terms; and (3) development and verification of codes (a) mathematical and computer simulation and (b) analytical and experimental comparisons

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.

Laser ignitibility of insensitive secondary explosive 1,1-diamino-2,2-dinitroethene (FOX-7)

International Nuclear Information System (INIS)

Fang, Xiao; McLuckie, Warren G

2015-01-01

Highlights: • Carbon black (CB) is an efficient optical sensitizer compatible with 1,1-diamino-2,2-dinitroethene (FOX-7). • A CB doped insensitive explosive FOX-7 can be ignited by a low-power diode laser. • Laser ignitibility of the optically sensitized FOX-7 is mainly affected by laser power among the other parameters. • Inhomogeneities in the explosive affect laser ignition reliability. - Abstract: An experimental investigation into laser ignitibility of insensitive secondary explosives, 1,1-diamino-2,2-dinitroethene (FOX-7) has been carried out, using a diode laser of continuous wave at the laser wavelength of 974 nm. The direct optical ignition of an insensitive explosive will add more safety features to insensitive munitions (IM) or explosive devices. In this study, effects of laser parameters on the ignitibility were analysed in terms of laser ignition threshold, the times to initiate the ignition and full combustion, and burning sustainability. The results have shown that carbon black (CB) as an optical sensitizer is compatible with FOX-7, and significantly enhances laser ignitibility of the explosive when a small amount of CB is uniformly doped in FOX-7. The delay times for ignition and subsequent development of sustainable burning of the material are mainly determined by ignition laser power, although the other laser parameters have effects. The minimum laser power required to ignite the optically sensitized FOX-7 was found below 10 W and a fast ignition was initiated in as short as 70 μs by a laser power of 40 W. Also the effect of the mixture uniformity of FOX-7/CB on laser ignition performance was evaluated in this study

Explosive performance on the non-proliferation experiment

Energy Technology Data Exchange (ETDEWEB)

McKown, T.O. [Los Alamos National Lab., NM (United States)

1994-12-31

The Explosive Effects Physics Project at the Los Alamos National Laboratory planned and conducted experiments on the Non-Proliferation Experiment (NPE) as part of its effort to define source functions for seismic waves. Since all investigations were contingent on the performance of the emplaced chemical explosive, an array of diagnostic measurements was fielded in the emplaced explosive. The CORRTEX (COntinuous Reflectometry for Radius vs Time EXperiment) system was used to investigate the explosive initiation and to determine the detonation velocities on three levels and in a number of radial directions. The CORRTEX experiments fielded in the explosive chamber will be described, including a description of the explosive emplacement from the perspective of its impact on the CORRTEX results. The data obtained are reviewed and the resulting detonation velocities are reported. A variation of detonation velocity with depth in the explosive and the apparent underdetonation and overdetonation of the explosive in different radial directions is reported.

Residual Stress Development in Explosive-Bonded Bi-Metal Composite Materials

Science.gov (United States)

2014-03-01

solidification cracking in steels and stainless steels . He has also undertaken extensive work on improving the weld zone toughness of high strength steels ...information on microstructural characterisation at the interface of ferritic- martensitic and austenitic steels produced using the EW process, the...957. [3] I. Tatsukawa, I. Oda, ‘Residual Stress Measurements on Explosive Clad Stainless Steel ’, Trans. Japan Welding Soc., 2(2), 1971, p26-34

Development of a non-explosive release actuator using shape memory alloy wire.

Science.gov (United States)

Yoo, Young Ik; Jeong, Ju Won; Lim, Jae Hyuk; Kim, Kyung-Won; Hwang, Do-Soon; Lee, Jung Ju

2013-01-01

We have developed a newly designed non-explosive release actuator that can replace currently used release devices. The release mechanism is based on a separation mechanism, which relies on segmented nuts and a shape memory alloy (SMA) wire trigger. A quite fast and simple trigger operation is made possible through the use of SMA wire. This actuator is designed to allow a high preload with low levels of shock for the solar arrays of medium-size satellites. After actuation, the proposed device can be easily and instantly reset. Neither replacement, nor refurbishment of any components is necessary. According to the results of a performance test, the release time, preload capacity, and maximum shock level are 50 ms, 15 kN, and 350 G, respectively. In order to increase the reliability of the actuator, more than ten sets of performance tests are conducted. In addition, the proposed release actuator is tested under thermal vacuum and extreme vibration environments. No degradation or damage was observed during the two environment tests, and the release actuator was able to operate successfully. Considering the test results as a whole, we conclude that the proposed non-explosive release actuator can be applied reliably to intermediate-size satellites to replace existing release systems.

The behavior limestone under explosive load

Science.gov (United States)

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

2016-11-01

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

Nuclear explosions and their effects

Energy Technology Data Exchange (ETDEWEB)

1958-01-01

A brief historical background is given of the development of the atomic bomb. Also included is an account of the Hiroshima-Nagasaki bombing, plus some information on the testing and production of nuclear weapons by the United States, United Kingdom, and Russia. More detailed consideration is given to the following: the scientific principles of fission and fusion explosions; the energy released in fission and the radioactivity of fission products; blast, thermal, and radiologicalal effects of nuclear explosions; long-term radiological hazards from fall-out; and genetic effects of nuclear explosions. A brief account is given of the fission chain process, the concept of critical size, and the principles of implosion as applied to nuclear explosions. Limited information is presented on the controlled release of thermonuclear energy and catalyzed fusion reaction. Discussions are included on dose rates from radiation sources inside and outside the body, the effect of nuclear explosions on the weather, and the contamination of fish and marine organisms.

Phenomenological modelling of steam explosions

International Nuclear Information System (INIS)

Corradini, M.L.; Drumheller, D.S.

1980-01-01

During a hypothetical core meltdown accident, an important safety issue to be addressed is the potential for steam explosions. This paper presents analysis and modelling of experimental results. There are four observations that can be drawn from the analysis: (1) vapor explosions are suppressed by noncondensible gases generated by fuel oxidation, by high ambient pressure, and by high water temperatures; (2) these effects appear to be trigger-related in that an explosion can again be induced in some cases by increasing the trigger magnitude; (3) direct fuel liquid-coolant liquid contact can explain small scale fuel fragmentation; (4) heat transfer during the expansion phase of the explosion can reduce the work potential

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...

The role of fragmentation mechanism in large-scale vapor explosions

International Nuclear Information System (INIS)

Liu, Jie

2003-01-01

A non-equilibrium, multi-phase, multi-component code PROVER-I is developed for propagation phase of vapor explosion. Two fragmentation models are used. The hydrodynamic fragmentation model is the same as Fletcher's one. A new thermal fragmentation model is proposed with three kinds of time scale for modeling instant fragmentation, spontaneous nucleation fragmentation and normal boiling fragmentation. The role of fragmentation mechanisms is investigated by the simulations of the pressure wave propagation and energy conversion ratio of ex-vessel vapor explosion. The spontaneous nucleation fragmentation results in a much higher pressure peak and a larger energy conversion ratio than hydrodynamic fragmentation. The instant fragmentation gives a slightly larger energy conversion ratio than spontaneous nucleation fragmentation, and the normal boiling fragmentation results in a smaller energy conversion ratio. The detailed analysis of the structure of pressure wave makes it clear that thermal detonation exists only under the thermal fragmentation circumstance. The high energy conversion ratio is obtained in a small vapor volume fraction. However, in larger vapor volume fraction conditions, the vapor explosion is weak. In a large-scale vapor explosion, the hydrodynamic fragmentation is essential when the pressure wave becomes strong, so a small energy conversion ratio is expected. (author)

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.

Effects of CuBr addition to CH3NH3PbI3(Cl) perovskite photovoltaic devices

Science.gov (United States)

Oku, Takeo; Ohishi, Yuya; Tanaka, Hiroki

2018-01-01

Effects of CuBr addition to perovskite CH3NH3PbI3(Cl) precursor solutions on photovoltaic properties were investigated. The CH3NH3Pb(Cu)I3(Cl,Br)-based photovoltaic devices were fabricated by a spin-coating technique, and the microstructures of the devices were investigated by X-ray diffraction, optical microscopy and scanning electron microscopy. Current density-voltage characteristics were improved by a small amount of CuBr addition, which resulted in improvement of the conversion efficiencies of the devices. The structure analysis showed decrease of unit cell volume and increase of Cu/Br composition by the CuBr addition, which would indicate the Cu/Br substitution at the Pb/I sites in the perovskite crystal, respectively.

27 CFR 555.181 - Reporting of plastic explosives.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Reporting of plastic..., FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of Plastic Explosives § 555.181 Reporting of plastic explosives. All persons, other than an agency of the United States...

STIDP: A U.S. Department of Homeland Security program for countering explosives attacks at large public events and mass transit facilities

Science.gov (United States)

Knudson, Christa K.; Kemp, Michael C.; Lombardo, Nicholas J.

2009-05-01

The U.S. Department of Homeland Security's Standoff Technology Integration and Demonstration Program is designed to accelerate the development and integration of technologies, concepts of operations, and training to defeat explosives attacks at large public events and mass transit facilities. The program will address threats posed by suicide bombers, vehicle-borne improvised explosive devices, and leave-behind bombs. The program is focused on developing and testing explosives countermeasure architectures using commercial off-the-shelf and near-commercial standoff and remotely operated detection technologies in prototypic operational environments. An important part of the program is the integration of multiple technologies and systems to protect against a wider range of threats, improve countermeasure performance, increase the distance from the venue at which screening is conducted, and reduce staffing requirements. The program will routinely conduct tests in public venues involving successively more advanced technology, higher levels of system integration, and more complex scenarios. This paper describes the initial field test of an integrated countermeasure system that included infrared, millimeter-wave, and video analytics technologies for detecting person-borne improvised explosive devices at a public arena. The test results are being used to develop a concept for the next generation of integrated countermeasures, to refine technical and operational requirements for architectures and technologies, and engage industry and academia in solution development.

On-site inspection for the radionuclide observables of an underground nuclear explosion

International Nuclear Information System (INIS)

Burnett, J.L.

2015-01-01

Under the Comprehensive Nuclear-Test-Ban Treaty an on-site inspection (OSI) may be undertaken to identify signatures from a potential nuclear explosion. This includes the measurement of 17 particulate radionuclides ( 95 Zr, 95 Nb, 99 Mo, 99m Tc, 103 Ru, 106 Rh, 132 Te, 131 I, 132 I, 134 Cs, 137 Cs, 140 Ba, 140 La, 141 Ce, 144 Ce, 144 Pr, 147 Nd). This research provides an assessment of the potential to detect these radionuclides during an OSI within 1 week to 2 years after a nuclear explosion at two locations. A model has been developed that simulates the underground detonation of a 1 kT 235 U nuclear weapon with 1 % venting. This indicates a requirement to minimise the time since detonation with accurate determination of the test location. (author)

Monte Carlo simulation of explosive detection system based on a Deuterium-Deuterium (D-D) neutron generator.

Science.gov (United States)

Bergaoui, K; Reguigui, N; Gary, C K; Brown, C; Cremer, J T; Vainionpaa, J H; Piestrup, M A

2014-12-01

An explosive detection system based on a Deuterium-Deuterium (D-D) neutron generator has been simulated using the Monte Carlo N-Particle Transport Code (MCNP5). Nuclear-based explosive detection methods can detect explosives by identifying their elemental components, especially nitrogen. Thermal neutron capture reactions have been used for detecting prompt gamma emission (10.82MeV) following radiative neutron capture by (14)N nuclei. The explosive detection system was built based on a fully high-voltage-shielded, axial D-D neutron generator with a radio frequency (RF) driven ion source and nominal yield of about 10(10) fast neutrons per second (E=2.5MeV). Polyethylene and paraffin were used as moderators with borated polyethylene and lead as neutron and gamma ray shielding, respectively. The shape and the thickness of the moderators and shields are optimized to produce the highest thermal neutron flux at the position of the explosive and the minimum total dose at the outer surfaces of the explosive detection system walls. In addition, simulation of the response functions of NaI, BGO, and LaBr3-based γ-ray detectors to different explosives is described. Copyright © 2014 Elsevier Ltd. All rights reserved.

Atmospheric emission of NOx from mining explosives: A critical review

Science.gov (United States)

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

2017-10-01

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

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.

Electron and nuclear dynamics of molecular clusters in ultraintense laser fields. IV. Coulomb explosion of molecular heteroclusters.

Science.gov (United States)

Last, Isidore; Jortner, Joshua

2004-11-01

In this paper we present a theoretical and computational study of the temporal dynamics and energetics of Coulomb explosion of (CD4)(n) and (CH4)(n) (n=55-4213) molecular heteroclusters in ultraintense (I=10(16)-10(19) W cm(-2)) laser fields, addressing the manifestation of electron dynamics, together with nuclear energetic and kinematic effects on the heterocluster Coulomb instability. The manifestations of the coupling between electron and nuclear dynamics were explored by molecular dynamics simulations for these heteroclusters coupled to Gaussian laser fields (pulse width tau=25 fs), elucidating outer ionization dynamics, nanoplasma screening effects (being significant for Icharges and masses. Nonuniform heterocluster Coulomb explosion (eta >1) manifests an overrun effect of the light ions relative to the heavy ions, exhibiting the expansion of two spatially separated subclusters, with the light ions forming the outer subcluster at the outer edge of the spatial distribution. Important features of the energetics of heterocluster Coulomb explosion originate from energetic triggering effects of the driving of the light ions by the heavy ions (C(4+) for I=10(17)-10(18) W cm(-2) and C(6+) for I=10(19) W cm(-2)), as well as for kinematic effects. Based on the CVI assumption, scaling laws for the cluster size (radius R(0)) dependence of the energetics of uniform Coulomb explosion of heteroclusters (eta=1) were derived, with the size dependence of the average (E(j,av)) and maximal (E(j,M)) ion energies being E(j,av)=aR(0) (2) and E(j,M)=(5a/3)R(0) (2), as well as for the ion energy distributions P(E(j)) proportional to E(j) (1/2); E(j)1) result in an isotope effect, predicting the enhancement (by 9%-11%) of E(H,av) for Coulomb explosion of (C(4+)H(4) (+))(eta) (eta=3) relative to E(D,av) for Coulomb explosion of (C(4+)D(4) (+))(eta) (eta=1.5), with the isotope effect being determined by the ratio of the kinematic parameters for the pair of Coulomb exploding clusters

Analysis, comparison, and modeling of radar interferometry, date of surface deformation signals associated with underground explosions, mine collapses and earthquakes. Phase I: underground explosions, Nevada Test Site

International Nuclear Information System (INIS)

Foxall, W; Vincent, P; Walter, W

1999-01-01

We have previously presented simple elastic deformation modeling results for three classes of seismic events of concern in monitoring the CTBT-underground explosions, mine collapses and earthquakes. Those results explored the theoretical detectability of each event type using synthetic aperture radar interferometry (InSAR) based on commercially available satellite data. In those studies we identified and compared the characteristics of synthetic interferograms that distinguish each event type, as well the ability of the interferograms to constrain source parameters. These idealized modeling results, together with preliminary analysis of InSAR data for the 1995 mb 5.2 Solvay mine collapse in southwestern Wyoming, suggested that InSAR data used in conjunction with regional seismic monitoring holds great potential for CTBT discrimination and seismic source analysis, as well as providing accurate ground truth parameters for regional calibration events. In this paper we further examine the detectability and ''discriminating'' power of InSAR by presenting results from InSAR data processing, analysis and modeling of the surface deformation signals associated with underground explosions. Specifically, we present results of a detailed study of coseismic and postseismic surface deformation signals associated with underground nuclear and chemical explosion tests at the Nevada Test Site (NTS). Several interferograms were formed from raw ERS-1/2 radar data covering different time spans and epochs beginning just prior to the last U.S. nuclear tests in 1992 and ending in 1996. These interferograms have yielded information about the nature and duration of the source processes that produced the surface deformations associated with these events. A critical result of this study is that significant post-event surface deformation associated with underground nuclear explosions detonated at depths in excess of 600 meters can be detected using differential radar interferometry. An

Reduction of radioactivity produced by nuclear explosives

Energy Technology Data Exchange (ETDEWEB)

Lessler, Richard M [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-15

Four main sources contribute to the radioactivity produced by a nuclear explosive: 1. Fission products from the nuclear explosive, 2. Fusion products from the nuclear explosive, 3. Induced radioactivity in the nuclear explosive, 4. Induced radioactivity in the environment. This paper will summarize some of the work done at the Lawrence Radiation Laboratory at Livermore to reduce the radioactivity from these sources to levels acceptable for peaceful applications. Although it is theoretically possible to have no radioactivity produced by nuclear explosives, this goal has not been achieved.

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.

Investigation of the explosion hazards of hydrogen sulphide

International Nuclear Information System (INIS)

Saber, A.J.; Sulmistras, A.; Moen, I.O.; Thibault, P.A.

1986-03-01

The results of Phase I of an investigation directed towards quantifying the explosion hazards of hydrogen sulphide in air are described. The first phase is focussed on detonation in free hydrogen sulphide/air clouds. Detonation properties, including velocity and pressure, have been calculated and compared with experimental results. The observed detonation structure together with critical tube tests tests are used to assess the detonability of hydrogen sulphide/air mixtures relative to hydrogen and common hydrocarbon gases. Detailed chemical kinetic modelling of hydrogen sulphide combustion in air has been performed to correlate the detonation cell size data and to determine the influence of water vapour on the detonability of hydrogen sulphide in air. Calculations of the blast wave properties for detonation of a hydrogen sulphide/air cloud provide the data required to assess the blast effects of such explosions

Simulated nuclear optical signatures using explosive light sources (ELS)

International Nuclear Information System (INIS)

Glaser, R.F.

1979-05-01

Four Explosive Light Source (aluminium powder and oxygen) tests were conducted on the test range at Sandia Laboratories in Albuquerque (SLA) from 28 February through 7 March 1978. Although several types of measuring devices were used, the report documents only the optical time histories measured by the bhangmeters and the NBDS, and explains the conclusions reached. In general, the four shots made it possible to gather clear-air optical transmission data, determine the suitability of ELS to simulate the optical effects of a nuclear burst, and provide experience for the larger scale ELS tests to be conducted at Fort Ord, CA in April

Simulated nuclear optical signatures using explosive light sources (ELS)

Energy Technology Data Exchange (ETDEWEB)

Glaser, R.F.

1979-05-01

Four Explosive Light Source (aluminium powder and oxygen) tests were conducted on the test range at Sandia Laboratories in Albuquerque (SLA) from 28 February through 7 March 1978. Although several types of measuring devices were used, the report documents only the optical time histories measured by the bhangmeters and the NBDS, and explains the conclusions reached. In general, the four shots made it possible to gather clear-air optical transmission data, determine the suitability of ELS to simulate the optical effects of a nuclear burst, and provide experience for the larger scale ELS tests to be conducted at Fort Ord, CA in April.

On-site comprehensive analysis of explosives using HPLC-UV-PAED

Science.gov (United States)

Marple, Ronita L.; LaCourse, William R.

2004-03-01

High-performance liquid chromatography with ultra violet and photo-assisted electrochemical detection (HPLC-UV-PAED) has been developed for the sensitive and selective detection of explosives in ground water and soil extracts. Fractionation and preconcentration of explosives is accomplished with on-line solid phase extraction (SPE), which minimizes sample pretreatment and enables faster and more accurate on-site assessment of a contaminated site. Detection limits are equivalent or superior (i.e., applicable, as it is capable of determining a wider range of organic nitro compounds. Soil samples are extracted using pressurized fluid extraction (PFE), and this technique is automatable, field-compatible, and environmentally friendly, adding to the overall efficiency of the methodology.

Explosions of Thorne-Żytkow objects

Science.gov (United States)

Moriya, Takashi J.

2018-03-01

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

Explosives mimic for testing, training, and monitoring

Science.gov (United States)

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.

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

Science.gov (United States)

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

1981-01-01

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

Near-Source Mechanism for Creating Shear Content from Buried Explosions

Science.gov (United States)

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

2017-12-01

The Source Physics Experiment (SPE) has the goal of developing a greater understanding of explosion phenomenology at various spatial scales, from near-source to the far-field. SPE Phase I accomplished a series of six chemical explosive tests of varying scaled depth of burial within a borehole in granite. The testbed included an extensive array of triaxial accelerometers. Velocity traces derived from these accelerometers allow for detailed study of the shock environment close in to the explosion. A specific goal of SPE is to identify various mechanisms for generating shear within the propagation environment and how this might be informative on the identification of explosive events that otherwise fail historic compression wave energy/shear wave energy (P/S) event discrimination. One of these sources was hypothesized to derive from slippage along joint sets near to the source. Velocity traces from SPE Phase I events indicate that motion tangential to a theoretically spherical shock wave are initially quiescent after shock arrival. But this period of quiescence is followed by a sudden increase in amplitude that consistently occurs just after the peak of the radial velocity (i.e., onset of shock unloading). The likelihood of occurrence of this response is related to yield-scaled depth-of-burial (SDOB). We describe a mechanism where unloading facilitates dilation of closed joints accompanied by a release of shear energy stored during compression. However, occurrence of this mechanism relies on relative amplitudes between the shock loading caused at a point and the in situ stress: at too large a SDOB the stored energy is insufficient to overcome the combination of the overburden stress and traction on the joint. On the other hand, too small of a SDOB provides that the in situ stress is insufficient to keep joints from storing stress, thus overriding the release mechanism and mitigating rupture-like slippage. We develop a notional relationship between SPE Phase I SDOB and

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)

Glass produced by underground nuclear explosions

International Nuclear Information System (INIS)

Schwartz, L.; Piwinskii, A.; Ryerson, F.; Tewes, H.; Beiriger, W.

1983-01-01

Detonation of an underground nuclear explosive produces a strong shock wave which propagates spherically outward, vaporizing the explosive and nearby rock and melting, the surrounding rock. The vaporized material expands adiabatically, forming a cavity. As the energy is dissipated during the cavity formation process, the explosive and rock debris condense and mix with the melted rock. The melt flows to the bottom of the cavity where it is quenched by fractured rock fragments falling from above as the cavity collapses. Measurements indicate that about 740 tonnes of rock and/or soil are melted for every kiloton (10 12 calories) of explosive energy, or about 25% of the explosive energy goes to melting rock. The resulting glass composition reflects the composition of the unaltered rock with explosive debris. The appearance ranges from white pumice to dense, dark lava. The bulk composition and color vary with the amount of explosive iron incorporated into the glass. The refractory explosion products are mixed with the solidified melt, although the degree of mixing is variable. Electron microprobe studies of glasses produced by Rainier in welded tuff have produced the following results: glasses are dehydrated relative to the host media, glasses are extremely heterogeneous on a 20 μm scale, a ubiquitous feature is the presence of dark marble-cake regions in the glass, which were locally enriched in iron and may be related to the debris, optically amorphous regions provide evidence of shock melting, only limited major element redistribution and homogenization occur within the cavity

Optimizing IEEE 802.11i resource and security essentials for mobile and stationary devices

CERN Document Server

Amiri, IS; Saberi, Iman

2014-01-01

In the past decade, the number of wireless devices has grown exponentially. Decades ago, all systems were wired computer systems. Wireless technology was not accessible in mobile and portable devices until in recent years, and has followed a variety of methods for encryption and resource management. The purpose of the research in Optimizing IEE 802.11i Resources and Security Essentials is to determine the issues of the performance in current encryption methods in AES-CCMP in different types of devices and handle it so that an optimized resource usage would be achieved with the required securi

English language learners' reading self-efficacy and achievement using 1:1 mobile learning devices

OpenAIRE

Walters, Jennifer L.

2012-01-01

Handheld technology devices allow users to be mobile and access the Internet, personal data, and third-party content applications in many different environments at the users' convenience. The explosion of these mobile learning devices around the globe has led adults to value them for communication, productivity, and learning. Outside of the school setting, many adolescents and children have access to, or own mobile devices. The use of these individual devices by children on a daily basis in s...

Nucleosynthesis in cold white dwarf explosions

International Nuclear Information System (INIS)

Canal, R.; Hernanz, M.

1986-01-01

Type I supernovae (SNI) are generally thought to be the main contributors to the galactic nucleosynthesis of iron-peak elements and their yields of intermediate-mass elements may also be important. We concentrate here upon a different class of models, based on the explosion of cold, massive, partially solid white dwarfs. We show that such white dwarfs must be relatively frequent among SNI progenitors and how their hydrodynamics upon ignition is very different from that of hotter, fluid white dwarfs. The implications for nucleosynthesis are briefly discussed and some preliminary results are presented

Aerosol can puncture device operational test plan

International Nuclear Information System (INIS)

Leist, K.J.

1994-01-01

Puncturing of aerosol cans is performed in the Waste Receiving and Processing Facility Module 1 (WRAP 1) process as a requirement of the waste disposal acceptance criteria for both transuranic (TRU) waste and low-level waste (LLW). These cans have contained such things as paints, lubricating oils, paint removers, insecticides, and cleaning supplies which were used in radioactive facilities. Due to Westinghouse Hanford Company (WHC) Fire Protection concerns of the baseline system's fire/explosion proof characteristics, a study was undertaken to compare the baseline system's design to commercially available puncturing devices. While the study found no areas which might indicate a risk of fire or explosion, WHC Fire Protection determined that the puncturing system must have a demonstrated record of safe operation. This could be obtained either by testing the baseline design by an independent laboratory, or by substituting a commercially available device. As a result of these efforts, the commercially available Aerosolv can puncturing device was chosen to replace the baseline design. Two concerns were raised with the system. Premature blinding of the coalescing/carbon filter, due to its proximity to the puncture and draining operation; and overpressurization of the collection bottle due to its small volume and by blinding of the filter assembly. As a result of these concerns, testing was deemed necessary. The objective of this report is to outline test procedures for the Aerosolv

Performance of electrical contact pins near a nuclear explosion

International Nuclear Information System (INIS)

Ragan, C.E.; Silbert, M.G.; Ellis, A.N.; Robinson, E.E.; Daddario, M.J.

1977-09-01

The pressures attainable in equation-of-state studies using nuclear-explosion-driven shock waves greatly exceed those that can be reached in normal laboratory conditions. However, the diagnostic instrumentation must survive in the high-radiation environment present near such an explosion. Therefore, a set of experiments were fielded on the Redmud event to test the feasibility of using electrical contact pins in this environment. In these experiments a 60-cm-high shield of boron-lead was placed on the rack lid approximately 1 m from the device. A sample consisting of slabs of molybdenum and 238 U was placed on top of the shield, and twelve electrical contact pins were embedded to five different depths in the materials. Five different multiplexing-charging circuits were used for the pins, and a piezoelectric quartz gauge was placed on top of the uranium to obtain an estimate of the fission-energy deposition. All of the charged pins survived the radiation and produced signals indicating shock arrival. The uncertainty in determining the pin-closure time was approximately 3 ns. The signal from the quartz gauge corresponded to a pressure that was consistent with the calculated neutron fluence

Study on explosives and their quality performance

Energy Technology Data Exchange (ETDEWEB)

Nabiullah, M.; Pingua, B.M.P.; Jagdish Khan, M.; Emranuzzaman [Central Mining Research Institute, Dhanbad (India)

2005-07-01

There are about forty suppliers of explosive and blasting accessories in India manufacturing site mixed emulsion, site mixed slurry, ANFO, HANFO, packed products, and blasting accessories of use in surface and underground mines. A field laboratory was set up to measure explosive properties of explosive samples, cast booster, detonating fuse, detonators, cord relay, MS connector, and shock tubes. Density, velocity of detonation, water percentage, water resistance, and energy output were considered as the important properties of explosives. A rating system was designed for selection of good explosive products. The delay interval and delay scattering in cord relay and shock tube was studied to improve blast performance. This paper describes in detail the method of measurement and vender rating system for explosive products as per marking system accepted by Coal India. 12 refs., 4 figs., 22 tabs.

Explosive coalescence of Magnetic Islands

International Nuclear Information System (INIS)

Tajima, T.; Sakai, J.I.

1985-04-01

An explosive reconnection process associated with nonlinear evolution of the coalescence instability is found through studies of particle and magnetohydrodynamic simulations. The explosive coalescence is a self-similar process of magnetic collapse, in which the magnetic and electrostatic energies and temperatures explode toward the explosion time t 0 as (t 0 -t)/sup 8/3/,(t 0 -t) -4 , and (t 0 -t)/sup -8/3/, respectively. Ensuing amplitude oscillations in these quantities are identified by deriving an equation of motion for the scale factor in the Sagdeev potential

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...

Gas induced fire and explosion frequencies

International Nuclear Information System (INIS)

Coutts, D.A.

1997-01-01

The use and handling of flammable gases poses a fire and explosion hazard to many DOE nuclear facilities. This hazard is not unique to DOE facilities. Each year over 2,900 non-residential structural fires occur in the U.S. where a gas is the first item ignited. Details from these events are collected by the National Fire Incident Reporting System (NFIRS) through an extensive reporting network. This extensive data set (800,000 fires in non-residential structures over a 5-year period) is an underutilized resource within the DOE community. Explosions in nuclear facilities can have very severe consequences. The explosion can both damage the facility containment and provide a mechanism for significant radiological dispersion. In addition, an explosion can have significant worker safety implications. Because of this a quantitative frequency estimate for explosions in an SRS laboratory facility has been prepared using the NFIRS data. 6 refs., 1 tab

Computational evaluation of some lower limbs protective systems under explosive loading

Directory of Open Access Journals (Sweden)

Casas J.P.

2012-08-01

Full Text Available Different types of protective equipment for human lower limb, such as boots and gaiters, have been developed in order to reduce the injury caused by blast antipersonnel-mines. Damage is mainly studied by the energy transmitted to the extremity that has stepped on the mine; nonetheless, side effects that may affect adjacent limbs cannot be left aside. This study is divided into three stages due to the complexity in modeling the different phenomena related to the problem. The first stage is the study of the energy transmitted when a mine is activated. Different results are gathered according to the variation of parameters such as: deep of burial, standoff between ground and protective equipment, explosive mass, energy absorbing material placed between the ground and the protected limb, and computational issues like the distance of the boundary conditions and the discretization level. The second stage is the base and first approximation to the modeling and evaluation of lower limb behavior. It includes the interaction of the detonation products and a lower limb that is placed in a mechanical measuring device. The energy transferred to the mechanical device is correlated to the damage caused by the explosion products in an attempt to validate previously experimental data. Finally, in the third stage, the side effect on the lower contiguous leg is assessed: pressure and temperature measures are taken at different distances according to the human pace in order to evaluate the worst-case scenario. The first and third stages propose different material arrangements or configurations to reduce the energy transmitted to the mechanical device and to mitigate damage caused to the contiguous limb respectively. All the three stages are simulated using two-dimensional (2D hydrocode Ansys AUTODYN ® and material previously reported in literature.

Computational evaluation of some lower limbs protective systems under explosive loading

Science.gov (United States)

Calle, J. C.; Coronado, R.; Rodriguez, J.; Casas, J. P.

2012-08-01

Different types of protective equipment for human lower limb, such as boots and gaiters, have been developed in order to reduce the injury caused by blast antipersonnel-mines. Damage is mainly studied by the energy transmitted to the extremity that has stepped on the mine; nonetheless, side effects that may affect adjacent limbs cannot be left aside. This study is divided into three stages due to the complexity in modeling the different phenomena related to the problem. The first stage is the study of the energy transmitted when a mine is activated. Different results are gathered according to the variation of parameters such as: deep of burial, standoff between ground and protective equipment, explosive mass, energy absorbing material placed between the ground and the protected limb, and computational issues like the distance of the boundary conditions and the discretization level. The second stage is the base and first approximation to the modeling and evaluation of lower limb behavior. It includes the interaction of the detonation products and a lower limb that is placed in a mechanical measuring device. The energy transferred to the mechanical device is correlated to the damage caused by the explosion products in an attempt to validate previously experimental data. Finally, in the third stage, the side effect on the lower contiguous leg is assessed: pressure and temperature measures are taken at different distances according to the human pace in order to evaluate the worst-case scenario. The first and third stages propose different material arrangements or configurations to reduce the energy transmitted to the mechanical device and to mitigate damage caused to the contiguous limb respectively. All the three stages are simulated using two-dimensional (2D) hydrocode Ansys AUTODYN ® and material previously reported in literature.

Safety problems with abandoned explosive facilities

International Nuclear Information System (INIS)

Courtright, W.C.

1969-01-01

Procedures were developed for the safe removal of explosive and radioactive contaminated materials structures and drains from abandoned sites, including explosives processing and service buildings with a goal to return the entire area to its natural state and to permit public access. The safety problems encountered in the cleanup and their solutions are applicable to modification and maintenance work in operating explosive facilities. (U.S.)

Steam explosions in sodium cooled breeder reactors

International Nuclear Information System (INIS)

Lundell, B.

1982-01-01

Steam explosion is considered a physical process which transport heat from molten fuel to liquid coolant so fast that the coolant starts boiling in an explosion-like manner. The arising pressure waves transform part of the thermal energy to mechanical energy. This can stress the reactor tank and threaten its hightness. The course of the explosion has not been theoretical explained. Experimental results indicate that the probability of steam explosions in a breeder reactor is small. The efficiency of the transformation of the heat of fusion into mechanical energy in substantially lower than the theoretical maximum value. The mechanical stress from the steam explosion on the reactor tank does not seem to jeopardize its tightness. (G.B.)

Hydrocarbon production with nuclear explosives

International Nuclear Information System (INIS)

Wade Watkins, J.

1970-01-01

The tremendous energy of nuclear explosives and the small dimensions of the explosive package make an ideal combination for drill-hole explosive emplacement in deep, thick hydrocarbon deposits. Potential applications exist in fracturing low permeability natural-gas and petroleum formations for stimulating production, fracturing oil shale to permit in situ retorting, and creating storage chimneys for natural gas, liquefied petroleum gas, petroleum, petroleum products, helium, and other fluids. Calculations show, for example, that less than 100 shots per year would be needed to stabilize the natural gas reserves to production ratio. Under the Government-industry Plowshare program, two experiments, Projects Gasbuggy and Rulison, were conducted to stimulate natural gas production from low-permeability formations. Incomplete information indicates that both were technically successful. Potential problems associated with the use of nuclear explosives for underground engineering applications are radioactive contamination, maximum yield limitations, high costs of detonating contained nuclear explosives, and adverse public opinion. Results at Project Gasbuggy and other considerations indicated that the problem of radioactive contamination was about as predicted and not an insurmountable one. Also, it was demonstrated that shots at adequate depths could be detonated without appreciable damage to existing surface and subsurface buildings, natural features, and equipment. However, costs must be reduced and the public must be better informed before these techniques can be widely used in field operations. On the basis of present knowledge, the potential of nuclear-explosive stimulation of hydrocarbon production appears good. Additional field experiments will be required to adequately explore that potential. (author)

Hydrocarbon production with nuclear explosives

Energy Technology Data Exchange (ETDEWEB)

Wade Watkins, J [Petroleum Research, Bureau of Mines, U.S. Department of the Interior, Washington, DC (United States)

1970-05-01

The tremendous energy of nuclear explosives and the small dimensions of the explosive package make an ideal combination for drill-hole explosive emplacement in deep, thick hydrocarbon deposits. Potential applications exist in fracturing low permeability natural-gas and petroleum formations for stimulating production, fracturing oil shale to permit in situ retorting, and creating storage chimneys for natural gas, liquefied petroleum gas, petroleum, petroleum products, helium, and other fluids. Calculations show, for example, that less than 100 shots per year would be needed to stabilize the natural gas reserves to production ratio. Under the Government-industry Plowshare program, two experiments, Projects Gasbuggy and Rulison, were conducted to stimulate natural gas production from low-permeability formations. Incomplete information indicates that both were technically successful. Potential problems associated with the use of nuclear explosives for underground engineering applications are radioactive contamination, maximum yield limitations, high costs of detonating contained nuclear explosives, and adverse public opinion. Results at Project Gasbuggy and other considerations indicated that the problem of radioactive contamination was about as predicted and not an insurmountable one. Also, it was demonstrated that shots at adequate depths could be detonated without appreciable damage to existing surface and subsurface buildings, natural features, and equipment. However, costs must be reduced and the public must be better informed before these techniques can be widely used in field operations. On the basis of present knowledge, the potential of nuclear-explosive stimulation of hydrocarbon production appears good. Additional field experiments will be required to adequately explore that potential. (author)

iStethoscope: a demonstration of the use of mobile devices for auscultation.

Science.gov (United States)

Bentley, Peter J

2015-01-01

iStethoscope Pro is the first piece of software (an "App") produced for iOS devices, which enabled users to exploit their smartphones, music players, or tablets as stethoscopes. The software exploits the built-in microphone (and supports externally added microphones) and performs real-time amplification and filtering to enable heart sounds to be heard with high fidelity. The software also enables the heart sounds to be recorded, analyzed using a spectrogram, and to be transmitted to others via e-mail. This chapter describes the motivation, functionality, and results from this work.

High-explosive driven crowbar switch

International Nuclear Information System (INIS)

Dike, R.S.; Kewish, R.W. Jr.

1976-01-01

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

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.

Mechanical constraints on the triggering of vulcanian explosions at Santiaguito volcano, Guatemala

Science.gov (United States)

Hornby, Adrian; Lavallée, Yan; Collinson, Amy; Neuberg, Jurgen; De Angelis, Silvio; Kendrick, Jackie; Lamur, Anthony

2016-04-01

to failure shows a non-linear increase as viscous deformation becomes more important (i.e. temperature is increased or strain rate decreased). This allows us to constrain timescales for fracture propagation for given temperature-strain rate scenarios. We use these results, together with monitoring data and the results of numerical modelling to compare the probability of fractures propagating from the top-down or bottom-up prior to explosions at Santiaguito. Thus, we shed light on the triggers and signals leading to vulcanian explosions, which may be widely applicable to vulcanian explosions at active volcanoes.

Type I supernova models

International Nuclear Information System (INIS)

Canal, Ramon; Labay, Javier; Isern, Jordi

1987-01-01

We briefly describe the characteristics of Type I supernova outbursts and we present the theoretical models so far advanced to explain them. We especially insist on models based on the thermonuclear explosion of a white dwarf in a close binary system, even regarding the recent division of Type I supernovae into the Ia and Ib subtypes. Together with models assuming explosive thermonuclear burning in a fluid interior, we consider in some detail those based on partially solid interiors. We finally discuss models that incorporate nonthermonuclear energy contributions, suggested in order to explain Type Ib outbursts. (Author)

Donor free radical explosive composition

Science.gov (United States)

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

1980-04-01

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

Peaceful applications of nuclear explosions

International Nuclear Information System (INIS)

Wallin, L.B.

1975-12-01

The intension of this report is to give a survey of the field of peaceful applications of nuclear explosions. As an introduction some examples of possibilities of application are given together with a simple description of nuclear explosions under ground. After a summary of what has been done and will be done in this field nationally and internationally, a short discussion of advantages and problems with peaceful application of nuclear explosions follows. The risks of spreading nuclear weapons due to this applications are also touched before the report is finished with an attempt to judge the future development in this field. (M.S.)

Novel high explosive compositions

Science.gov (United States)

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

1968-04-16

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

Teaching Functional Use of an iPod-Based Speech-Generating Device to Individuals with Developmental Disabilities

Science.gov (United States)

van der Meer, Larah; Kagohara, Debora; Achmadi, Donna; Green, Vanessa A.; Herrington, Christina; Sigafoos, Jeff; O'Reilly, Mark F.; Lancioni, Giulio E.; Lang, Russell; Rispoli, Mandy

2011-01-01

Anecdotal reports suggest that individuals with developmental disabilities who lack speech may be enabled to communicate through the use of a new iPod-based communication device. However, there appear to be limited empirical data demonstrating successful use of this new device by such individuals. This study was designed to provide empirical…

Explosion approach for external safety assessment: a case study

Energy Technology Data Exchange (ETDEWEB)

Johnson, D. Michael; Halford, Ann [Germanischer Lloyd, Loughborough (United Kingdom); Mendes, Renato F. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

2009-07-01

Several questions related to the potential for explosions are explored as this became an important subject during an enterprise risk analysis. The understanding of explosions underwent a substantial evolution in the final 20 years of the 20{sup th} century following international research projects in Europe involving several research institutes, as well gas and oil companies. This led to the development of techniques that could be used to assess the potential consequences of explosions on oil, gas and petrochemical facilities. This paper presents an overview of the potential for explosions in communities close to industrial sites or pipelines right of way (RoW), where the standard explosion assessment methods cannot be applied. With reference to experimental studies, the potential for confined explosions in buildings and Vapor Cloud Explosions is explored. Vapor Cloud Explosion incidents in rural or urban areas are also discussed. The method used for incorporating possible explosion and fire events in risk studies is also described using a case study. Standard explosion assessment methodologies and a revised approach are compared as part of an on going evaluation of risk (author)

Risk Quantitative Determination of Fire and Explosion in a Process Unit By Dow’s Fire and Explosion Index

Directory of Open Access Journals (Sweden)

S. Varmazyar

2008-04-01

Full Text Available Background and aims   Fire and explosion hazards are the first and second of major hazards in process industries, respectively. This study has been done to determine fire and explosion risk severity,radius of exposure and estimating of most probable loss.   Methods   In this quantitative study process unit has been selected with affecting parameters on  fire and explosion risk. Then, it was analyzed by DOW's fire and explosion index (F&EI. Technical data were obtained from process documents and reports, fire and explosion guideline.After calculating of DOW's index, radius of exposure determined and finally most  probable loss was estimated.   Results   The results showed an F&EI value of 226 for this process unit.The F&EI was extremely  high and unacceptable.Risk severity was categorized in sever class.Radius of exposure and damage factor were calculated 57 meters and 83%,respectively. As well as most probable loss was  estimated about 6.7 million dollars.   Conclusion   F&EI is a proper technique for risk assessment and loss estimation of fire and  explosion in process industries.Also,It is an important index for detecting high risk and low risk   areas in an industry. At this technique, all of factors affecting on fire and explosion risk was  showed as index that is a base for judgement risk class. Finally, estimated losses could be used as  a base of fire and explosion insurance.

27 CFR 555.63 - Explosives magazine changes.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Explosives magazine... § 555.63 Explosives magazine changes. (a) General. (1) The requirements of this section are applicable to magazines used for other than temporary (under 24 hours) storage of explosives. (2) A magazine is...

Explosive Leidenfrost droplets

Science.gov (United States)

Colinet, Pierre; Moreau, Florian; Dorbolo, Stéphane

2017-11-01

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

Risk of dust explosions of combustible nanomaterials

International Nuclear Information System (INIS)

Dobashi, Ritsu

2009-01-01

Nanomaterials have several valuable properties and are widely used for various practical applications. However, safety matters are suspected such as the influence on health and environment, and fire and explosion hazards. To minimize the risk of nanomaterials, appropriate understanding of these hazards is indispensable. Nanoparticles of combustible materials have potential hazard of dust explosion accidents. However, the explosion risk of nanomaterials has not yet been understood adequately because of the lack of data for nanomaterials. In this presentation, the risk of dust explosions of nanomaterials is discussed.

Kaliski's explosive driven fusion experiments

International Nuclear Information System (INIS)

Marshall, J.

1979-01-01

An experiment performed by a group in Poland on the production of DD fusion neutrons by purely explosive means is discussed. A method for multiplying shock velocities ordinarily available from high explosives by a factor of ten is described, and its application to DD fusion experiments is discussed

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

Science.gov (United States)

Patel, C. K. N.

2008-01-01

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

Assessment of the critical neutron number for internal break-even in explosion-induced thermonuclear fusion

International Nuclear Information System (INIS)

Kaliski, S.

1979-01-01

An analysis is performed of the systems of an explosion-induced thermonuclear microfusion from the angle of attaining an internal break-even. A critical-state meter is defined, i.e. the critical neutron yield Nsub(cr) as the most convenient for characterizing the experimental setups. It is demonstrated that in a number of designed systems of an explosion-induced microfusion, Nsub(cr) is attained. In the experiments actually carried out the N-yield efficiency is of about three orders of magnitude. (author)

The experimental investigation of explosive opening switch

Energy Technology Data Exchange (ETDEWEB)

Jiande, Zhang; Huihuang, Zhong; Chuanlu, Li; Yonggui, Liu; Dongqun, Cheng; Xianyang, Peng [National Univ. of Defense Technology, Changsha (China). Dept. of Applied Physics

1997-12-31

The explosive opening switch (EOS) used in explosive-driven magnetic-flux compression generator (EMCG) circuits was investigated. It is shown that (1) under certain conditions, the EOS voltage is hardly dependent on the size of the explosive and aluminium foil used in EOS; (2) with the explosive coated by an insulator pipe, the opening effect of EOS is better; (3) by use of EOS, a pulse with 5 kA current, 100 kV voltage and 250 ns risetime has been transferred into a resistance load. (author). 12 figs., 5 refs.

The experimental investigation of explosive opening switch

International Nuclear Information System (INIS)

Zhang Jiande; Zhong Huihuang; Li Chuanlu; Liu Yonggui; Cheng Dongqun; Peng Xianyang

1996-01-01

The explosive opening switch (EOS) used in explosive-driven magnetic-flux compression generator (EMCG) circuits was investigated. It is shown that (1) under certain conditions, the EOS voltage is hardly dependent on the size of the explosive and aluminium foil used in EOS; (2) with the explosive coated by an insulator pipe, the opening effect of EOS is better; (3) by use of EOS, a pulse with 5 kA current, 100 kV voltage and 250 ns risetime has been transferred into a resistance load. (author). 12 figs., 5 refs

Apparatus for forming an explosively expanded tube-tube sheet joint

International Nuclear Information System (INIS)

Schroeder, J.W.

1984-01-01

The invention relates to apparatus for expanding a tube into a bore formed in a tube sheet. According to the invention, a primary explosive containing a relatively high number of grains of explosive per unit length extends within the tube coextensive with that portion of the tube to be expanded. An energy transfer cord extends between a detonator and the primary explosive and includes a relatively low number of grains of explosive per unit length which are insufficient to detonate the primary explosive. The transfer cord is covered by a sheath to contain the debris and gases associated with the explosion of the explosive therein. A booster extends between the energy transfer cord and the primary explosive and contains an explosive which can be detonated by the explosive in the energy transfer cord and can, upon exploding, in turn detonate the primary explosive. (author)

Explosions on a gas-vacuum interface

International Nuclear Information System (INIS)

Nutt, G.; Klein, L.; Ratcliffe, A.E.

1981-01-01

A finite-difference computer code is used to calculate the time development of an explosion on a gas-vacuum interface. An analytic theory of the shape of the shock wave produced in the explosion is compared with the results of the computer simulation. The assumptions used in obtaining this analytic solution are verified, and the degree to which the variables describing the explosion are self-similar is examined. Finally, certain consistency relations among the similarity exponents are tested

Remote laser drilling and sampling system for the detection of concealed explosives

Science.gov (United States)

Wild, D.; Pschyklenk, L.; Theiß, C.; Holl, G.

2017-05-01

The detection of hazardous materials like explosives is a central issue in national security in the field of counterterrorism. One major task includes the development of new methods and sensor systems for the detection. Many existing remote or standoff methods like infrared or raman spectroscopy find their limits, if the hazardous material is concealed in an object. Imaging technologies using x-ray or terahertz radiation usually yield no information about the chemical content itself. However, the exact knowledge of the real threat potential of a suspicious object is crucial for disarming the device. A new approach deals with a laser drilling and sampling system for the use as verification detector for suspicious objects. Central part of the system is a miniaturised, diode pumped Nd:YAG laser oscillator-amplifier. The system allows drilling into most materials like metals, synthetics or textiles with bore hole diameters in the micron scale. During the drilling process, the hazardous material can be sampled for further investigation with suitable detection methods. In the reported work, laser induced breakdown spectroscopy (LIBS) is used to monitor the drilling process and to classify the drilled material. Also experiments were carried out to show the system's ability to not ignite even sensitive explosives like triacetone triperoxide (TATP). The detection of concealed hazardous material is shown for different explosives using liquid chromatography and ion mobility spectrometry.

Electromagnetic field effects in explosives

Science.gov (United States)

Tasker, Douglas

2009-06-01

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

Dynamics of explosively imploded pressurized tubes

Science.gov (United States)

Szirti, Daniel; Loiseau, Jason; Higgins, Andrew; Tanguay, Vincent

2011-04-01

The detonation of an explosive layer surrounding a pressurized thin-walled tube causes the formation of a virtual piston that drives a precursor shock wave ahead of the detonation, generating very high temperatures and pressures in the gas contained within the tube. Such a device can be used as the driver for a high energy density shock tube or hypervelocity gas gun. The dynamics of the precursor shock wave were investigated for different tube sizes and initial fill pressures. Shock velocity and standoff distance were found to decrease with increasing fill pressure, mainly due to radial expansion of the tube. Adding a tamper can reduce this effect, but may increase jetting. A simple analytical model based on acoustic wave interactions was developed to calculate pump tube expansion and the resulting effect on the shock velocity and standoff distance. Results from this model agree quite well with experimental data.

Development of Network Devices Supporting Communication Independence In NPP I and C Systems

International Nuclear Information System (INIS)

Jeong, K.-I.; Suh, Y.S.; Park, G.-O.; Park, J.-Y.

2013-06-01

As advanced digital I and C systems of nuclear power plants or research reactors are being introduced to replace analog systems, a data communication network is necessary for data exchanges between I and C systems of nuclear power plants or research reactors. Data communication network technology may have significant impact on I and C systems. As the safety I and C system is composed of redundant channels to enhance the performance of the safety functions and data communication system is used to transmit the data generated by the digital I and C systems, communication independence is required to mitigate the risk of safety I and C system failure. Therefore this paper mainly discusses the issues related to the communication independence and the current status of network devices we designed, developed, and validated to satisfy the requirements of function, performance, and communication independence. (authors)

Research on Initiation Sensitivity of Solid Explosive and Planer Initiation System

Directory of Open Access Journals (Sweden)

N Matsuo

2016-09-01

Full Text Available Firstly, recently, there are a lot of techniques being demanded for complex process, various explosive initiation method and highly accurate control of detonation are needed. In this research, the metal foil explosion using high current is focused attention on the method to obtain linear or planate initiation easily, and the main evaluation of metal foil explosion to initiate explosive was conducted. The explosion power was evaluated by observing optically the underwater shock wave generated from the metal foil explosion. Secondly, in high energy explosive processing, there are several applications, such as shock compaction, explosive welding, food processing and explosive forming. In these explosive applications, a high sensitive explosive has been mainly used. The high sensitive explosive is so dangerous, since it can lead to explosion suddenly. So, for developing explosives, the safety is the most important thing as well as low manufacturing cost and explosive characteristics. In this work, we have focused on the initiation sensitivity of a solid explosive and performed numerical analysis of sympathetic detonation. The numerical analysis is calculated by LS-DYNA 3D (commercial code. To understand the initiation reaction of an explosive, Lee-Tarver equation was used and impact detonation process was analyzed by ALE code. Configuration of simulation model is a quarter of circular cylinder. The donor type of explosive (SEP was used as initiation explosive. When the donor explosive is exploded, a shock wave is generated and it propagates into PMMA, air and metallic layers in order. During passing through the layers, the shock wave is attenuated and finally, it has influence on the acceptor explosive, Comp. B. Here, we evaluate the initiation of acceptor explosive and discuss about detonation pressure, reactive rate of acceptor explosive and attenuation of impact pressure.

Blast overpressure after tire explosion: a fatal case.

Science.gov (United States)

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

2013-12-01

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

Engineering effects of underground nuclear explosions

International Nuclear Information System (INIS)

Boardman, Charles R.

1970-01-01

Useful effects of contained underground nuclear explosions are discussed in light of today's most promising potential applications. Relevant data obtained through exploration of explosion environments of nine U.S. tests in competent rock are summarized and presented as a practical basis for estimating magnitudes of effects. Effects discussed include chimney configuration, permeability, and volume as well as rubble particle size distributions and extents of permeability change in the chimney wall rock. Explosion mediums include shale, granite, dolomite, and salt. (author)

Engineering effects of underground nuclear explosions

Energy Technology Data Exchange (ETDEWEB)

Boardman, Charles R [CER Geonuclear Corporation, Las Vegas, NV (United States)

1970-05-01

Useful effects of contained underground nuclear explosions are discussed in light of today's most promising potential applications. Relevant data obtained through exploration of explosion environments of nine U.S. tests in competent rock are summarized and presented as a practical basis for estimating magnitudes of effects. Effects discussed include chimney configuration, permeability, and volume as well as rubble particle size distributions and extents of permeability change in the chimney wall rock. Explosion mediums include shale, granite, dolomite, and salt. (author)

An Intercomparison of Model Predictions for an Urban Contamination Resulting from the Explosion of a Radiological Dispersal Device

Energy Technology Data Exchange (ETDEWEB)

Hwang, Won Tae; Jeong, Hyo Jun; Kim, Eun Han; Han, Moon Hee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2009-03-15

The METRO-K is a model for a radiological dose assessment due to a radioactive contamination in the Korean urban environment. The model has been taken part in the Urban Remediation Working Group within the IAEA's (International Atomic Energy Agency) EMRAS (Environmental Modeling for Radiation Safety) program. The Working Croup designed for the intercomparison of radioactive contamination to be resulted from the explosion of a radiological dispersal device in a hypothetical city. This paper dealt intensively with a part among a lot of predictive results which had been performed in the EMRAS program. The predictive results of three different models (METRO-K, RESRAD-RDD, CPHR) were submitted to the Working Group. The gap of predictive results was due to the difference of mathematical modeling approaches, parameter values, understanding of assessors. Even if final results (for example, dose rates from contaminated surfaces which might affect to a receptor) are similar, the understanding on the contribution of contaminated surfaces showed a great difference. Judging from the authors, it is due to the lack of understanding and information on radioactive terrors as well as the social and cultural gaps which assessors have been experienced. Therefore, it can be known that the experience of assessors and their subjective judgements might be important factors to get reliable results. If the acquisition of a little additional information is possible, it was identified that the METRO-K might be a useful tool for decision support against contamination resulting from radioactive terrors by improving the existing model.

An Intercomparison of Model Predictions for an Urban Contamination Resulting from the Explosion of a Radiological Dispersal Device

International Nuclear Information System (INIS)

Hwang, Won Tae; Jeong, Hyo Jun; Kim, Eun Han; Han, Moon Hee

2009-01-01

The METRO-K is a model for a radiological dose assessment due to a radioactive contamination in the Korean urban environment. The model has been taken part in the Urban Remediation Working Group within the IAEA's (International Atomic Energy Agency) EMRAS (Environmental Modeling for Radiation Safety) program. The Working Croup designed for the intercomparison of radioactive contamination to be resulted from the explosion of a radiological dispersal device in a hypothetical city. This paper dealt intensively with a part among a lot of predictive results which had been performed in the EMRAS program. The predictive results of three different models (METRO-K, RESRAD-RDD, CPHR) were submitted to the Working Group. The gap of predictive results was due to the difference of mathematical modeling approaches, parameter values, understanding of assessors. Even if final results (for example, dose rates from contaminated surfaces which might affect to a receptor) are similar, the understanding on the contribution of contaminated surfaces showed a great difference. Judging from the authors, it is due to the lack of understanding and information on radioactive terrors as well as the social and cultural gaps which assessors have been experienced. Therefore, it can be known that the experience of assessors and their subjective judgements might be important factors to get reliable results. If the acquisition of a little additional information is possible, it was identified that the METRO-K might be a useful tool for decision support against contamination resulting from radioactive terrors by improving the existing model.

Research of explosives in an environment of high pressure and temperature using a new test stand

Directory of Open Access Journals (Sweden)

Jan Drzewiecki

2015-01-01

Full Text Available In this article the test stand for determining the blast abilities of explosives in high pressure and temperature conditions as well as the initial results of the research are presented. Explosives are used in rock burst and methane prevention to destroy precisely defined fragments of the rock mass where energy and methane are accumulated. Using this preventive method for fracturing the structure of the rocks which accumulate the energy or coal of the methane seam very often does not bring the anticipated results. It is because of the short range of destructive action of the post-blast gases around the blast hole. Evaluation of the blast dynamics of explosives in a test chamber, i.e. in the pressure and temperature conditions comparable to those found “in situ”, will enable evaluation of their real usefulness in commonly used mining hazard preventive methods. At the same time, it will enable the development of new designs of the explosive charges used for precisely determined mining hazards. In order to test the explosives for their use in difficult environmental conditions and to determine the characteristics of their explosion, a test chamber has been built. It is equipped with a system of sensors and a high-frequency recording system of pressure and temperature during a controlled explosion of an explosive charge. The results of the research will enable the development of new technologies for rock burst and methane prevention which will significantly increase workplace health and safety level. This paper presented results constitute the initial phase of research started in the middle of 2014.

Shot H3837: Darht's First Dual-Axis Explosive Experiment

Science.gov (United States)

Mendez, Jacob; McNeil, Wendy Vogan; Harsh, James; Hull, Lawrence

2011-06-01

Test H3837 was the first explosive shot performed in front of both flash x-ray axes at the Los Alamos Dual Axis Radiographic HydroTest (DARHT) facility. Executed in November 2009, the shot was an explosively-driven metal flyer plate in a series of experiments designed to explore equation-of-state properties of shocked materials. Imaging the initial shock wave traveling through the flyer plate, DARHT Axis II captured the range of motion from the shock front emergence in the flyer to breakout at the free surface; the Axis I pulse provided a perpendicular perspective of the shot at a time coinciding with the third pulse of Axis II. Since the days of the Manhattan Project, penetrating radiography with multiple frames from different viewing angles has remained a high-profile goal at the Laboratory. H3837 is merely the beginning of a bright future for two-axis penetrating radiography.

In-vessel coolability and steam explosion in Nordic BWRs

International Nuclear Information System (INIS)

Ma, W.; Hansson, R.; Li, L.; Kudinov, P.; Cadinu, F.; Tran, C-.T.

2010-05-01

The INCOSE project is to reduce the uncertainty in quantification of steam explosion risk and in-vessel coolability in Nordic BWR plants with the cavity flooding as a severe accident management (SAM) measure. During 2009 substantial advances and new insights into physical mechanisms were gained for studies of: (i) in-vessel corium coolability - development of the methodologies to assess the efficiency of the control rod guide tube (CRGT) cooling as a potential SAM measure; (ii) debris bed coolability - characterization of the effective particle diameter of multi-size particles and qualification of friction law for two-phase flow in the beds packed with multi-size particles; and (iii) steam explosion - investigation of the effect of binary oxides mixtures properties on steam explosion. An approach for coupling of ECM/PECM models with RELAP5 was developed to enhance predictive fidelity for melt pool heat transfer. MELCOR was employed to examine the CRGT cooling efficiency by considering an entire accident scenario, and the simulation results show that the nominal flowrate (∼10kg/s) of CRGT cooling is sufficient to maintain the integrity of the vessel in a BWR of 3900 MWth, if the water injection is activated no later than 1 hour after scram. The POMECO-FL experimental data suggest that for a particulate bed packed with multi-size particles, the effective particle diameter can be represented by the area mean diameter of the particles, while at high velocity (Re>7) the effective particle diameter is closer to the length mean diameter. The pressure drop of two-phase flow through the particulate bed can be predicted by Reed's model. The steam explosion experiments performed at high melt superheat (>200oC) using oxidic mixture of WO3-CaO didn't detect an apparent difference in steam explosion energetics and preconditioning between the eutectic and noneutectic melts. This points out that the next step of MISTEE experiment will be conducted at lower superheat. (author)

Laser-based optical detection of explosives

CERN Document Server

Pellegrino, Paul M; Farrell, Mikella E

2015-01-01

Laser-Based Optical Detection of Explosives offers a comprehensive review of past, present, and emerging laser-based methods for the detection of a variety of explosives. This book: Considers laser propagation safety and explains standard test material preparation for standoff optical-based detection system evaluation Explores explosives detection using deep ultraviolet native fluorescence, Raman spectroscopy, laser-induced breakdown spectroscopy, reflectometry, and hyperspectral imaging Examines photodissociation followed by laser-induced fluorescence, photothermal methods, cavity-enhanced absorption spectrometry, and short-pulse laser-based techniques Describes the detection and recognition of explosives using terahertz-frequency spectroscopic techniques Each chapter is authored by a leading expert on the respective technology, and is structured to supply historical perspective, address current advantages and challenges, and discuss novel research and applications. Readers are left with an in-depth understa...

Effects of iPod Touch™ Technology as Communication Devices on Peer Social Interactions across Environments

Science.gov (United States)

Mancil, G. Richmond; Lorah, Elizabeth R.; Whitby, Peggy Schaefer

2016-01-01

The purpose of the study was to evaluate the use of the iPod Touch™ as a Speech Generated Device (SGD) for Functional Communication Training (FCT). The evaluation of the effects on problem behavior, the effects on generalization and maintenance of the acquired communication repertoire, and the social initiations of peers between the new SGD (iPod…

Regulatory Experience of the Embedded Digital Devices for Safety I and C Systems on Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Kim, Y. M.; Lee, H. K.; Park, H. S. [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

2016-10-15

Conventional I and C(Instrumentation and Control) systems are tend to becoming unavailable and being replaced by smart equipment. These smart equipment is usually called embedded digital devices (EDDs) or industrial digital devices of limited functionality. Usually, some of these devices are found embedded in plant equipment such as sensing instrumentation, motors, pumps, actuators and breakers. They typically have a micro-processor, RAM, communication interface, a power source, etc. The U.S. Nuclear Regulatory Commission (US NRC) is concerning that these EDDs might exist in procured equipment used in safety systems without the devices having been explicitly identified in procurement documentation. This paper addresses the regulatory experiences of KINS of the EDDs for safety I and C systems and the future works for them. In this paper, we showed regulatory experiences of EDDs which used for safety grade equipment. EDDs might exist in safety grade procured equipment without explicit identification. Undetected defects of EDDs might be the potential safety concerns. EDDs should meet certain specific requirements in order to be selected and used in safety I and C system. We have plan to develop technical positions for identification and qualifying them. The technical position will address, but may not be limited to, quality and reliability, CCFs via software errors, EMC, and CGID for EDDs.

Review of Soviet studies related to peaceful underground nuclear explosions

International Nuclear Information System (INIS)

Lin, W.

1978-01-01

Theoretical and empirical studies of contained and crater-forming underground nuclear explosions by USSR investigators are reviewed and summarized. Published data on U.S., USSR, and French cavity-forming nuclear explosions are compared with those predicted by the formula. Empirical studies on U.S. and USSR cratering explosions, both high explosions, both high explosive and nuclear are summarized. The parameters governing an excavation explosion are reviewed

The CTBT Verification Regime: Monitoring the Earth for nuclear explosions

International Nuclear Information System (INIS)

2011-03-01

The Comprehensive nuclear-Test-Ban Treaty (CTBT) bans all nuclear weapon tests. Its unique verification regime is designed to detect nuclear explosions anywhere on the planet - in the oceans, underground and in the atmosphere. once complete, the international Monitoring system (iMs) will consist of 337 facilities located in 89 countries around the globe. The iMs is currently operating in test mode so that data are already transmitted for analysis from monitoring facilities to the international Data Centre (iDC) at the headquarters of the preparatory Commission for the Comprehensive nuclear-Test-Ban Treaty Organization (CTBTO) in Vienna. Data and analysis results are shared with Member states.

Inhomogeneous wire explosion in water

International Nuclear Information System (INIS)

Hwangbo, C.K.; Kong, H.J.; Lee, S.S.

1980-01-01

Inhomogeneous processes are observed in underwater copper wire explosion induced by a condensed capacitor discharge. The wire used is 0.1 mm in diameter and 10 mm long, and the capacitor of 2 μF is charged to 5 KV. A N 2 laser is used for the diagnostic of spatial extension of exploding copper vapour. The photographs obtained in this experiment show unambiguously the inhomogeneous explosion along the exploding wire. The quenching of plasma by the surrounding water inhibits the expansion of the vapour. It is believed the observed inhomogeneous explosion along the wire is located and localized around Goronkin's striae, which was first reported by Goronkin and discussed by Froengel as a pre-breakdown phenomenon. (author)

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

Ultrafast Coulomb explosion of a diiodomethane molecule induced by an X-ray free-electron laser pulse.

Science.gov (United States)

Takanashi, Tsukasa; Nakamura, Kosuke; Kukk, Edwin; Motomura, Koji; Fukuzawa, Hironobu; Nagaya, Kiyonobu; Wada, Shin-Ichi; Kumagai, Yoshiaki; Iablonskyi, Denys; Ito, Yuta; Sakakibara, Yuta; You, Daehyun; Nishiyama, Toshiyuki; Asa, Kazuki; Sato, Yuhiro; Umemoto, Takayuki; Kariyazono, Kango; Ochiai, Kohei; Kanno, Manabu; Yamazaki, Kaoru; Kooser, Kuno; Nicolas, Christophe; Miron, Catalin; Asavei, Theodor; Neagu, Liviu; Schöffler, Markus; Kastirke, Gregor; Liu, Xiao-Jing; Rudenko, Artem; Owada, Shigeki; Katayama, Tetsuo; Togashi, Tadashi; Tono, Kensuke; Yabashi, Makina; Kono, Hirohiko; Ueda, Kiyoshi

2017-08-02

Coulomb explosion of diiodomethane CH 2 I 2 molecules irradiated by ultrashort and intense X-ray pulses from SACLA, the Japanese X-ray free electron laser facility, was investigated by multi-ion coincidence measurements and self-consistent charge density-functional-based tight-binding (SCC-DFTB) simulations. The diiodomethane molecule, containing two heavy-atom X-ray absorbing sites, exhibits a rather different charge generation and nuclear motion dynamics compared to iodomethane CH 3 I with only a single heavy atom, as studied earlier. We focus on charge creation and distribution in CH 2 I 2 in comparison to CH 3 I. The release of kinetic energy into atomic ion fragments is also studied by comparing SCC-DFTB simulations with the experiment. Compared to earlier simulations, several key enhancements are made, such as the introduction of a bond axis recoil model, where vibrational energy generated during charge creation processes induces only bond stretching or shrinking. We also propose an analytical Coulomb energy partition model to extract the essential mechanism of Coulomb explosion of molecules from the computed and the experimentally measured kinetic energies of fragment atomic ions by partitioning each pair Coulomb interaction energy into two ions of the pair under the constraint of momentum conservation. Effective internuclear distances assigned to individual fragment ions at the critical moment of the Coulomb explosion are then estimated from the average kinetic energies of the ions. We demonstrate, with good agreement between the experiment and the SCC-DFTB simulation, how the more heavily charged iodine fragments and their interplay define the characteristic features of the Coulomb explosion of CH 2 I 2 . The present study also confirms earlier findings concerning the magnitude of bond elongation in the ultrashort X-ray pulse duration, showing that structural damage to all but C-H bonds does not develop to a noticeable degree in the pulse length of ∼10

Ideas for peaceful nuclear explosions in USSR

International Nuclear Information System (INIS)

1970-01-01

Three papers prepared in USSR have been made available to the Agency for circulation among Member States. One examines radioactive contamination and methods for predicting it, of natural environments during underground explosions. Another deals with the mechanical effect of underground explosions. The third, which forms the basis of this article, reviews possible applications of peaceful nuclear explosions in the Soviet economy. (author)

Inelastic processes in seismic wave generation by underground explosions

Energy Technology Data Exchange (ETDEWEB)

Rodean, H.C.

1980-08-01

Theories, computer calculations, and measurements of spherical stress waves from explosions are described and compared, with emphasis on the transition from inelastic to almost-elastic relations between stress and strain. Two aspects of nonspherical explosion geometry are considered: tectonic strain release and surface spall. Tectonic strain release affects the generation of surface waves; spall closure may also. The reduced-displacement potential is a common solution (the equivalent elastic source) of the forward and inverse problems, assuming a spherical source. Measured reduced-displacement potentials are compared with potentials calculated as solutions of the direct and inverse problems; there are significant differences between the results of the two types of calculations and between calculations and measurements. The simple spherical model of an explosion is not sufficient to account for observations of explosions over wide ranges of depth and yield. The explosion environment can have a large effect on explosion detection and yield estimation. The best sets of seismic observations for use in developing discrimination techniques are for high-magnitude high-yield explosions; the identification problem is most difficult for low-magnitude low-yield explosions. Most of the presently available explosion data (time, medium, depth, yield, etc.) are for explosions in a few media at the Nevada Test Site; some key questions concerning magnitude vs yield and m/sub b/ vs M/sub s/ relations can be answered only by data for explosions in other media at other locations.

Inelastic processes in seismic wave generation by underground explosions

International Nuclear Information System (INIS)

Rodean, H.C.

1980-01-01

Theories, computer calculations, and measurements of spherical stress waves from explosions are described and compared, with emphasis on the transition from inelastic to almost-elastic relations between stress and strain. Two aspects of nonspherical explosion geometry are considered: tectonic strain release and surface spall. Tectonic strain release affects the generation of surface waves; spall closure may also. The reduced-displacement potential is a common solution (the equivalent elastic source) of the forward and inverse problems, assuming a spherical source. Measured reduced-displacement potentials are compared with potentials calculated as solutions of the direct and inverse problems; there are significant differences between the results of the two types of calculations and between calculations and measurements. The simple spherical model of an explosion is not sufficient to account for observations of explosions over wide ranges of depth and yield. The explosion environment can have a large effect on explosion detection and yield estimation. The best sets of seismic observations for use in developing discrimination techniques are for high-magnitude high-yield explosions; the identification problem is most difficult for low-magnitude low-yield explosions. Most of the presently available explosion data (time, medium, depth, yield, etc.) are for explosions in a few media at the Nevada Test Site; some key questions concerning magnitude vs yield and m/sub b/ vs M/sub s/ relations can be answered only by data for explosions in other media at other locations

The fracture of concrete under explosive shock loading

International Nuclear Information System (INIS)

Watson, A.J.; Sanderson, A.J.

1982-01-01

Concrete fracture close to the point of application of high explosive shock pressures has been studied experimentally by placing an explosive charge on the edge of a concrete slab. The extent of the crushing and cracking produced by a semi cylindrical diverging plane compressive stress pulse has been measured and complementary experiments gave the pressure transmitted at an explosive to concrete interface and the stress-strain relation for concrete at explosive strain rates. (orig.) [de

Insensitive detonator apparatus for initiating large failure diameter explosives

Science.gov (United States)

Perry, III, William Leroy

2015-07-28

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

Underground Nuclear Explosions and Release of Radioactive Noble Gases

Science.gov (United States)

Dubasov, Yuri V.

2010-05-01

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

THE BIGGEST EXPLOSIONS IN THE UNIVERSE

International Nuclear Information System (INIS)

Johnson, Jarrett L.; Whalen, Daniel J.; Smidt, Joseph; Even, Wesley; Fryer, Chris L.; Heger, Alex; Chen, Ke-Jung

2013-01-01

Supermassive primordial stars are expected to form in a small fraction of massive protogalaxies in the early universe, and are generally conceived of as the progenitors of the seeds of supermassive black holes (BHs). Supermassive stars with masses of ∼55, 000 M ☉ , however, have been found to explode and completely disrupt in a supernova (SN) with an energy of up to ∼10 55 erg instead of collapsing to a BH. Such events, ∼10, 000 times more energetic than typical SNe today, would be among the biggest explosions in the history of the universe. Here we present a simulation of such a SN in two stages. Using the RAGE radiation hydrodynamics code, we first evolve the explosion from an early stage through the breakout of the shock from the surface of the star until the blast wave has propagated out to several parsecs from the explosion site, which lies deep within an atomic cooling dark matter (DM) halo at z ≅ 15. Then, using the GADGET cosmological hydrodynamics code, we evolve the explosion out to several kiloparsecs from the explosion site, far into the low-density intergalactic medium. The host DM halo, with a total mass of 4 × 10 7 M ☉ , much more massive than typical primordial star-forming halos, is completely evacuated of high-density gas after ∼ ☉ after ∼> 70 Myr. The chemical signature of supermassive star explosions may be found in such long-lived second-generation stars today

The Magnetar Model of the Superluminous Supernova GAIA16apd and the Explosion Jet Feedback Mechanism

Energy Technology Data Exchange (ETDEWEB)

Soker, Noam, E-mail: soker@physics.technion.ac.il [Department of Physics, Technion—Israel Institute of Technology, Haifa 32000 (Israel)

2017-04-10

Under the assumption that jets explode core collapse supernovae (CCSNe) in a negative jet feedback mechanism (JFM), this paper shows that rapidly rotating neutron stars are likely to be formed when the explosion is very energetic. Under the assumption that an accretion disk or an accretion belt around the just-formed neutron star launch jets and that the accreted gas spins-up the just-formed neutron star, I derive a crude relation between the energy that is stored in the spinning neutron star and the explosion energy. This relation is ( E {sub NS-spin}/ E {sub exp}) ≈ E {sub exp}/10{sup 52} erg; It shows that within the frame of the JFM explosion model of CCSNe, spinning neutron stars, such as magnetars, might have significant energy in super-energetic explosions. The existence of magnetars, if confirmed, such as in the recent super-energetic supernova GAIA16apd, further supports the call for a paradigm shift from neutrino-driven to jet-driven CCSN mechanisms.

Establishment of data base of regional seismic recordings from earthquakes, chemical explosions and nuclear explosions in the Former Soviet Union

Energy Technology Data Exchange (ETDEWEB)

Ermolenko, N.A.; Kopnichev, Yu.F.; Kunakov, V.G.; Kunakova, O.K.; Rakhmatullin, M.Kh.; Sokolova, I.N.; Vybornyy, Zh.I. [AN SSSR, Moscow (Russian Federation). Inst. Fiziki Zemli

1995-06-01

In this report results of work on establishment of a data base of regional seismic recordings from earthquakes, chemical explosions and nuclear explosions in the former Soviet Union are described. This work was carried out in the Complex Seismological Expedition (CSE) of the Joint Institute of Physics of the Earth of the Russian Academy of Sciences and Lawrence Livermore National Laboratory. The recording system, methods of investigations and primary data processing are described in detail. The largest number of digital records was received by the permanent seismic station Talgar, situated in the northern Tien Shan, 20 km to the east of Almaty city. More than half of the records are seismograms of underground nuclear explosions and chemical explosions. The nuclear explosions were recorded mainly from the Semipalatinsk test site. In addition, records of the explosions from the Chinese test site Lop Nor and industrial nuclear explosions from the West Siberia region were obtained. Four records of strong chemical explosions were picked out (two of them have been produced at the Semipalatinsk test site and two -- in Uzbekistan). We also obtained 16 records of crustal earthquakes, mainly from the Altai region, close to the Semipalatinsk test site, and also from the West China region, close to the Lop Nor test site. In addition, a small number of records of earthquakes and underground nuclear explosions, received by arrays of temporary stations, that have been working in the southern Kazakhstan region are included in this report. Parameters of the digital seismograms and file structure are described. Possible directions of future work on the digitizing of unique data archive are discussed.

Workshop on explosions, BLEVEs, fires, etc.

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-31

The purpose of this workshop will be to provide a bridge between engineering practices, modeling, and measurement of fires and explosions, and use this information in a practical manner to improve the fire safety of the process facility. New techniques and information are available on the means to prevent, predict and mitigate fires and explosions. A review of BLEVEs and methods for preventing and protecting against the effects of BLEVES in large petrochemical facilities. Observations and the use of models that have been successful in predicting the effects of vapor explosions for the prevention of collapse of structures and mitigation of the effects of vapor explosions in process facilities are presented. Recent work involving the measurement of radiation from large jet fires at the Kuwaiti oil fields and fire tests of crude oil spills on the sea is discussed. Fire radiation measurement can be used to predict effects on structures, facilities, and the complexity of fire fighting operations required for control of spill and pool fires. Practical applications of techniques for prevention and control of explosions within building, resulting from failures of autoclaves or release of flammable gas to the atmosphere of the building are discussed.

What factors control superficial lava dome explosivity?

Science.gov (United States)

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

2015-09-30

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

Vent control device for nuclear reactor container

International Nuclear Information System (INIS)

Kubota, Ryuji.

1989-01-01

The present invention concerns automatic prevention of abnormal over-pressure and hydrogen gas flashing in a BWR type reactor container. That is, (1) if the pressure in the container is abnormally increased, the gas in the pressure suppression chamber is released to reduce the pressure thereby preventing over-pressure damage to the container. (2) Then, if exhaust gases are burnt to cause flashing explosion danger for the gases in the reactor container, the gas release is interrupted. The foregoing two functioins are automatically conducted in this device. Specifically, when the pressure in the reactor container reaches a predetermined allowable limit, a remote control operation valve is opened by automatic control means to release the gas in the vessel. Since the gas flow rate at the start of the release exceeds flame propagation velocity, there is no worry for flashing explosion. Further, if the pipeway flow velocity near the atmospheric release is reduced to less than the flame propagation velocity of the hydrogen gas, the opened valve is automatically closed. Accordingly, propagation of hydrogen gas flame into the container thus causing explosion can surely be prevented. (K.M.)

Search for isotopic signatures of a supernova explosion close to the solar system in marine sediments; Recherche de signatures isotopiques dans les sediments marins de l'explosion d'une supernova proche du systeme solaire

Energy Technology Data Exchange (ETDEWEB)

Fitoussi, Caroline [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, (CSNSM) IN2P3/CNRS, Campus d' Orsay, Bat 108, 91405 Orsay (France)

2006-06-15

The recent observation of a {sup 60}Fe peak in a deep-sea ferro-manganese crust has been interpreted as due to a supernova explosion relatively close to the solar system 2.8 {+-} 0.4 Myr ago. To confirm this interpretation with better time-resolved measurements, and the simultaneous access, on the same sample, to other isotopes and geochemical phases, marine sediments seem to be a tool of choice. The objective of this work was to search for isotopic anomalies which would be characteristic for residues of this supernova. More specifically, {sup 129}I, {sup 60}Fe, and {sup 26}Al have been investigated, being measured by Accelerator Mass Spectrometry (AMS). Quantifying these nuclides' fluxes would help constrain stellar nucleosynthesis models. These residues are isotopes initially produced during hydrostatic and/or explosive nucleosynthesis. The physical conditions during the explosion (temperature, neutron density) are such that supernovae are thought to be good candidates for the astrophysical site of the r-process. The {sup 129}I study showed that measurement of pre-anthropogenic {sup 129}I/{sup 127}I ratios need a very strict control of the various potential {sup 129}I sources, especially when working with small quantities (micrograms) of iodine. This study revealed that the expected pre-anthropogenic {sup 129}I/{sup 127}I ratio for pre-nuclear samples in the marine environment shows a large discrepancy between theoretical calculations and experimental measurements. {sup 60}Fe and {sup 26}Al measurements allow us to conclude that, in the authigenic phase of the marine sediments, there is no {sup 60}Fe anomaly in the time interval defined by the signal found on the Fe-Mn crust (from 2.4 to 3.2 Myr), and no {sup 26}Al anomaly from 2.6 to 3.2 Myr. (author)

Maritime Improvised Explosive Devices: A Threat Based Technology Study

Science.gov (United States)

2015-06-12

id/3078682/ns/technology_and_science- science/t/dolphins-go-front-lines-iraq-war/#.VPsmDZU5DIV. Carnegie , Dale , and Rita Kiley. 1948. How to Stop...Besides, if I let those things get me, I wouldn’t last long. ( Carnegie and Kiley 1948, 6) ― Admiral Ernest J. King Admiral King’s focus on

Photodissociation of aligned CH3I and C6H3F2I molecules probed with time-resolved Coulomb explosion imaging by site-selective extreme ultraviolet ionization.

Science.gov (United States)

Amini, Kasra; Savelyev, Evgeny; Brauße, Felix; Berrah, Nora; Bomme, Cédric; Brouard, Mark; Burt, Michael; Christensen, Lauge; Düsterer, Stefan; Erk, Benjamin; Höppner, Hauke; Kierspel, Thomas; Krecinic, Faruk; Lauer, Alexandra; Lee, Jason W L; Müller, Maria; Müller, Erland; Mullins, Terence; Redlin, Harald; Schirmel, Nora; Thøgersen, Jan; Techert, Simone; Toleikis, Sven; Treusch, Rolf; Trippel, Sebastian; Ulmer, Anatoli; Vallance, Claire; Wiese, Joss; Johnsson, Per; Küpper, Jochen; Rudenko, Artem; Rouzée, Arnaud; Stapelfeldt, Henrik; Rolles, Daniel; Boll, Rebecca

2018-01-01

We explore time-resolved Coulomb explosion induced by intense, extreme ultraviolet (XUV) femtosecond pulses from a free-electron laser as a method to image photo-induced molecular dynamics in two molecules, iodomethane and 2,6-difluoroiodobenzene. At an excitation wavelength of 267 nm, the dominant reaction pathway in both molecules is neutral dissociation via cleavage of the carbon-iodine bond. This allows investigating the influence of the molecular environment on the absorption of an intense, femtosecond XUV pulse and the subsequent Coulomb explosion process. We find that the XUV probe pulse induces local inner-shell ionization of atomic iodine in dissociating iodomethane, in contrast to non-selective ionization of all photofragments in difluoroiodobenzene. The results reveal evidence of electron transfer from methyl and phenyl moieties to a multiply charged iodine ion. In addition, indications for ultrafast charge rearrangement on the phenyl radical are found, suggesting that time-resolved Coulomb explosion imaging is sensitive to the localization of charge in extended molecules.

Use of explosives in pipeline construction work

Energy Technology Data Exchange (ETDEWEB)

Ball, M J

1976-08-01

Explosives are an essential tool in Great Britain's pipeline-construction industry, with applications on dry land and under water, in trench blasting and tunneling for road and service crossings, demolition of unwanted sections, and removal of coatings. Nobels Explosive Co. Ltd. describes basic explosives operations as pertaining to the requirements of rock trenching, submarine operations, thrust-bore and tunneling operations, demolitions, and precision blasting.

Health Consequences and Management of Explosive Events

Directory of Open Access Journals (Sweden)

Abbas Ostadtaghizadeh

2016-01-01

Conclusion: Because of the wide range and adverse impacts of explosions, healthcare authorities and staff should have a good grasp of preventive principles, as well as protection and management of explosion sites. Besides they have to be familiar with treating the injured. It is recommended that training courses and simulated explosive events be designed and run by the healthcare sector.

Impact of an iDevice application on student learning in an occupational therapy kinesiology course.

Science.gov (United States)

Hughes, Jason K; Kearney, Pamalyn

2017-01-01

As technology continues to evolve, and information is increasingly accessed through smartphones and tablets, it is essential for university faculty to reassess teaching methodologies. This study explored how use of an iDevice application (app) by participants enrolled in an entry-level occupational therapy kinesiology course affected student learning in the course. This iDevice app was developed through a collaboration between the lead author and the Department of Technology Enhanced Learning and Innovation at Augusta University. The iDevice app was released to the public via the Apple ® App Store at the midpoint of the kinesiology course. All students were invited to use the app. Focus groups were conducted with 19 students recruited from the first year cohort of occupational therapy graduate students. These focus groups were conducted at the end of the semester once grades had been submitted. Thematic analysis of focus group transcripts revealed three themes reflecting how participants perceived app use impacting their learning. Participants report the app facilitated learning through provision of visual content, serving as a reliable source of information, and generally supporting the learning process. The Kinesiology Pro Consult App provided on demand learning, allowing students to be more autonomous with their learning and take advantage of opportunities to learn anywhere and anytime. Finally, participants reported the app allowed them to be more efficient in their learning, possibly allowing more time for other courses. Mobile device apps that support student learning in specific content areas may provide positive benefits to student learning both in the specific course related to the app but also in other courses as a result of increased efficiency in learning.

The ALMA View of the OMC1 Explosion in Orion

International Nuclear Information System (INIS)

Bally, John; Youngblood, Allison; Ginsburg, Adam; Arce, Hector; Eisner, Josh; 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 ∼29 and ∼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 streamers with velocities extending from V LSR = −150 to +145 km s −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 2 and [Fe ii] “fingertips” and lower-velocity CO in the H 2 wakes comprising Orion's “fingers.” In some directions, the H 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 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.

Burn propagation in a PBX 9501 thermal explosion

International Nuclear Information System (INIS)

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

2007-01-01

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

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

Science.gov (United States)

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

2016-11-01

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

Improvised Explosive Devices in Iraq: Effects and Countermeasures

National Research Council Canada - National Science Library

Wilson, Clay

2005-01-01

.... and coalition forces since the invasion of Iraq. The bombs have been hidden behind signs and guardrails, under roadside debris, or inside animal carcasses, and encounters with IEDs are becoming more numerous and deadly...

Time-resolved dynamics of nanosecond laser-induced phase explosion

International Nuclear Information System (INIS)

Porneala, Cristian; Willis, David A

2009-01-01

Visualization of Nd : YAG laser ablation of aluminium targets was performed by a shadowgraph apparatus capable of imaging the dynamics of ablation with nanosecond time resolution. Direct observations of vaporization, explosive phase change and shock waves were obtained. The influence of vaporization and phase explosion on shock wave velocity was directly measured. A significant increase in the shock wave velocity was observed at the onset of phase explosion. However, the shock wave behaviour followed the form of a Taylor-Sedov spherical shock below and above the explosive phase change threshold. The jump in the shock wave velocity above phase explosion threshold is attributed to the release of stored enthalpy in the superheated liquid surface. The energy released during phase explosion was estimated by fitting the transient shock wave position to the Taylor scaling rules. Results of temperature calculations indicate that the vapour temperature at the phase explosion threshold is slightly higher than the critical temperature at the early stages of the shock wave formation. The shock wave pressure nearly doubled when transitioning from normal vaporization to phase explosion.

Calculating overpressure from BLEVE explosions

Energy Technology Data Exchange (ETDEWEB)

Planas-Cuchi, E.; Casal, J. [Universitat Politecnica de Catalunya, Barcelona (Spain). Department of Chemical Engineering, Centre for Technological Risk Studies; Salla, J.M. [Universitat Politecnica de Catalunya, Barcelona (Spain). Department of Heat Engines

2004-11-01

Although a certain number of authors have analyzed the prediction of boiling liquid expanding vapour explosion (BLEVE) and fireball effects, only very few of them have proposed methodologies for predicting the overpressure from such explosions. In this paper, the methods previously published are discussed and shown to introduce a significant overestimation due to erroneous thermodynamic assumptions - ideal gas behaviour and isentropic vapour expansion - on which they are based (in fact, they give the maximum value of overpressure which can be caused by a BLEVE). A new approach is proposed, based on the - more realistic - assumption of an adiabatic and irreversible expansion process; the real properties of the substance involved in the explosion are used. The two methods are compared through the application to a given case. (author)

Evidence for nearby supernova explosions

International Nuclear Information System (INIS)

Benitez, Narciso; Maiz-Apellaniz, Jesus; Canelles, Matilde

2002-01-01

Supernova (SN) explosions are one of the most energetic--and potentially lethal--phenomena in the Universe. We show that the Scorpius-Centaurus OB association, a group of young stars currently located at ∼130 pc from the Sun, has generated 20 SN explosions during the last 11 Myr, some of them probably as close as 40 pc to our planet. The deposition on Earth of 60 Fe atoms produced by these explosions can explain the recent measurements of an excess of this isotope in deep ocean crust samples. We propose that ∼2 Myr ago, one of the SNe exploded close enough to Earth to seriously damage the ozone layer, provoking or contributing to the Pliocene-Pleistocene boundary marine extinction

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

Science.gov (United States)

Bement, L. J.

1976-01-01

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

Development of an FPGA-based multipoint laser pyroshock measurement system for explosive bolts

International Nuclear Information System (INIS)

Abbas, Syed Haider; Lee, Jung-Ryul; Jang, Jae-Kyeong; Kim, Zaeill

2016-01-01

Pyroshock can cause failure to the objective of an aerospace structure by damaging its sensitive electronic equipment, which is responsible for performing decisive operations. A pyroshock is the high intensity shock wave that is generated when a pyrotechnic device is explosively triggered to separate, release, or activate structural subsystems of an aerospace architecture. Pyroshock measurement plays an important role in experimental simulations to understand the characteristics of pyroshock on the host structure. This paper presents a technology to measure a pyroshock wave at multiple points using laser Doppler vibrometers (LDVs). These LDVs detect the pyroshock wave generated due to an explosive-based pyrotechnical event. Field programmable gate array (FPGA) based data acquisition is used in the study to acquire pyroshock signals simultaneously from multiple channels. This paper describes the complete system design for multipoint pyroshock measurement. The firmware architecture for the implementation of multichannel data acquisition on an FPGA-based development board is also discussed. An experiment using explosive bolts was configured to test the reliability of the system. Pyroshock was generated using explosive excitation on a 22-mm-thick steel plate. Three LDVs were deployed to capture the pyroshock wave at different points. The pyroshocks captured were displayed as acceleration plots. The results showed that our system effectively captured the pyroshock wave with a peak-to-peak magnitude of 303 741 g. The contribution of this paper is a specialized architecture of firmware design programmed in FPGA for data acquisition of large amount of multichannel pyroshock data. The advantages of the developed system are the near-field, multipoint, non-contact, and remote measurement of a pyroshock wave, which is dangerous and expensive to produce in aerospace pyrotechnic tests.

Development of an FPGA-based multipoint laser pyroshock measurement system for explosive bolts

Energy Technology Data Exchange (ETDEWEB)

Abbas, Syed Haider; Lee, Jung-Ryul [Department of Aerospace Engineering, Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Jang, Jae-Kyeong [The Engineering Institute-Korea, Chonbuk National University, Jeonju (Korea, Republic of); Kim, Zaeill [The 4th R& D Institute-1st directorate, Agency for Defense Development, Daejeon (Korea, Republic of)

2016-07-15

Pyroshock can cause failure to the objective of an aerospace structure by damaging its sensitive electronic equipment, which is responsible for performing decisive operations. A pyroshock is the high intensity shock wave that is generated when a pyrotechnic device is explosively triggered to separate, release, or activate structural subsystems of an aerospace architecture. Pyroshock measurement plays an important role in experimental simulations to understand the characteristics of pyroshock on the host structure. This paper presents a technology to measure a pyroshock wave at multiple points using laser Doppler vibrometers (LDVs). These LDVs detect the pyroshock wave generated due to an explosive-based pyrotechnical event. Field programmable gate array (FPGA) based data acquisition is used in the study to acquire pyroshock signals simultaneously from multiple channels. This paper describes the complete system design for multipoint pyroshock measurement. The firmware architecture for the implementation of multichannel data acquisition on an FPGA-based development board is also discussed. An experiment using explosive bolts was configured to test the reliability of the system. Pyroshock was generated using explosive excitation on a 22-mm-thick steel plate. Three LDVs were deployed to capture the pyroshock wave at different points. The pyroshocks captured were displayed as acceleration plots. The results showed that our system effectively captured the pyroshock wave with a peak-to-peak magnitude of 303 741 g. The contribution of this paper is a specialized architecture of firmware design programmed in FPGA for data acquisition of large amount of multichannel pyroshock data. The advantages of the developed system are the near-field, multipoint, non-contact, and remote measurement of a pyroshock wave, which is dangerous and expensive to produce in aerospace pyrotechnic tests.

Explosives remain preferred methods for platform abandonment

International Nuclear Information System (INIS)

Pulsipher, A.; Daniel, W. IV; Kiesler, J.E.; Mackey, V. III

1996-01-01

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

Modeling the explosion-source region: An overview

International Nuclear Information System (INIS)

Glenn, L.A.

1993-01-01

The explosion-source region is defined as the region surrounding an underground explosion that cannot be described by elastic or anelastic theory. This region extends typically to ranges up to 1 km/(kt) 1/3 but for some purposes, such as yield estimation via hydrodynamic means (CORRTEX and HYDRO PLUS), the maximum range of interest is less by an order of magnitude. For the simulation or analysis of seismic signals, however, what is required is the time resolved motion and stress state at the inelastic boundary. Various analytic approximations have been made for these boundary conditions, but since they rely on near-field empirical data they cannot be expected to reliably extrapolate to different explosion sites. More important, without some knowledge of the initial energy density and the characteristics of the medium immediately surrounding the explosion, these simplified models are unable to distinguish chemical from nuclear explosions, identify cavity decoupling, or account for such phenomena as anomalous dissipation via pore collapse

Off-center point explosion in a spheroid

International Nuclear Information System (INIS)

Morita, Kazuhiko; Sakashita, Shiro

1978-01-01

An off-center point explosion in a spheroid with exponential or Gaussian density distribution is investigated by applying the generalized Laumbach and Probstein method. For a typical example, we calculate the explosion in a spheroid with the eccentricity e = 0.7. If the separation distance between the center of the spheroid and the explosion point is larger than three times of the density scale height, the shock wave may almost propagate toward the direction of the minor axis of symmetry, within the polar angle of 30 0 . The shock envelope elongates toward the same direction and may form a polar jet and/or a tilted jet. But, in the case of an explosion in the equatorial plane (perpendicular to the minor axis of symmetry), two plasmas with the same form may be ejected into two different directions with the angle smaller than 180 0 . Explosion models of double radio sources and related objects are suggested. (author)

A fault tree analysis (FTA) of hydrogen explosion potentiality on reduction furnace ME-11 in nuclear power fuel element fabrication process

International Nuclear Information System (INIS)

Achmad Suntoro

2012-01-01

Fault Tree Analysis (FTA) diagrams for the potentiality of hydrogen gas explosion in reduction furnace of ME-11 has been created after modification of its logic control. These FTA diagrams can be used as additional information in designing preventive maintenance program and operational steps of the furnace. The encountering of two conditions, i.e. explosion ignition and the potentially explosive of hydrogen gas, is the search focus of the FTA, and it may be done by breaking and tracing down to any possibility of initial causes for these two conditions to occur coincidently. Two locations of the potentially explosive area were identified: furnace chamber and combustion chamber of the exhaust gas. The possible explosion ignitions for the furnace are only from spark, fire and hot material because the operation of the furnace does not use high-pressure hydrogen. However, these explosion ignitions are part of the on going reduction process, therefore it is important that the hydrogen gas volume composition during the process always be supervised. (author)

Mobile Device Applications for the Visualization of Functional Connectivity Networks and EEG electrodes: iBraiN and iBraiNEEG.

Directory of Open Access Journals (Sweden)

Gonzalo Mauricio Rojas

2016-10-01

Full Text Available Multiple fMRI-based functional connectivity networks were obtained by Yeo et al., and the visualization of these complex networks is a difficult task. Also, the combination of functional connectivity networks determined by fMRI with EEG data could be a very useful tool. Mobile devices are becoming increasingly common among users, and for this reason, we describe here two applications for Android and iOS mobile devices: one that shows in an interactive way the seven Yeo functional connectivity networks, and another application that shows the relative position of 10-20 EEG electrodes with Yeo’s seven functional connectivity networks.

Mobile Device Applications for the Visualization of Functional Connectivity Networks and EEG Electrodes: iBraiN and iBraiNEEG.

Science.gov (United States)

Rojas, Gonzalo M; Fuentes, Jorge A; Gálvez, Marcelo

2016-01-01

Multiple functional MRI (fMRI)-based functional connectivity networks were obtained by Yeo et al. (2011), and the visualization of these complex networks is a difficult task. Also, the combination of functional connectivity networks determined by fMRI with electroencephalography (EEG) data could be a very useful tool. Mobile devices are becoming increasingly common among users, and for this reason, we describe here two applications for Android and iOS mobile devices: one that shows in an interactive way the seven Yeo functional connectivity networks, and another application that shows the relative position of 10-20 EEG electrodes with Yeo's seven functional connectivity networks.

Search for isotopic signatures of a supernova explosion close to the solar system in marine sediments

International Nuclear Information System (INIS)

Fitoussi, Caroline

2006-06-01

The recent observation of a 60 Fe peak in a deep-sea ferro-manganese crust has been interpreted as due to a supernova explosion relatively close to the solar system 2.8 ± 0.4 Myr ago. To confirm this interpretation with better time-resolved measurements, and the simultaneous access, on the same sample, to other isotopes and geochemical phases, marine sediments seem to be a tool of choice. The objective of this work was to search for isotopic anomalies which would be characteristic for residues of this supernova. More specifically, 129 I, 60 Fe, and 26 Al have been investigated, being measured by Accelerator Mass Spectrometry (AMS). Quantifying these nuclides' fluxes would help constrain stellar nucleosynthesis models. These residues are isotopes initially produced during hydrostatic and/or explosive nucleosynthesis. The physical conditions during the explosion (temperature, neutron density) are such that supernovae are thought to be good candidates for the astrophysical site of the r-process. The 129 I study showed that measurement of pre-anthropogenic 129 I/ 127 I ratios need a very strict control of the various potential 129 I sources, especially when working with small quantities (micrograms) of iodine. This study revealed that the expected pre-anthropogenic 129 I/ 127 I ratio for pre-nuclear samples in the marine environment shows a large discrepancy between theoretical calculations and experimental measurements. 60 Fe and 26 Al measurements allow us to conclude that, in the authigenic phase of the marine sediments, there is no 60 Fe anomaly in the time interval defined by the signal found on the Fe-Mn crust (from 2.4 to 3.2 Myr), and no 26 Al anomaly from 2.6 to 3.2 Myr. (author)

Explosive Evaporating Phenomena of Cryogenic Fluids by Direct Contacting Normal Temperature Fluids

Directory of Open Access Journals (Sweden)

T Watanabe

2016-09-01

Full Text Available Cryogenic fluids have characteristics such as thermal stratification and flashing by pressure release in storage vessel. The mixture of the extreme low temperature fluid and the normal temperature fluid becomes the cause which causes pressure vessel and piping system crush due to explosive boiling and rapid freezing. In recent years in Japan, the demand of cryogenic fluids like a LH2, LNG is increasing because of the advance of fuel cell device technology, hydrogen of engine, and stream of consciousness for environmental agreement. These fuel liquids are cryogenic fluids. On the other hand, as for fisheries as well, the use of a source of energy that environment load is small has been being a pressing need. And, the need of the ice is high, as before, for keeping freshness of marine products in fisheries. Therefore, we carried out the experiments related to promotion of evaporating cryogenic fluids and generation of ice, in the contact directly of the water and liquid nitrogen. From the results of visualization, phenomena of explosive evaporating and ice forming were observed by using video camera.

Explosions and light curves of supernovae

International Nuclear Information System (INIS)

Gaffet, B.

1975-01-01

The models developed to explain supernovae explosions are reviewed. The first one is thermonuclear explosion (simple or preceded by an implosion phase); the neutrino emission which results of such an explosion can have an important dynamical effect, according as the star is opaque or transparent to them; another theory involves the radiation pressure of the pulsar which is formed in the center of the star. The origin of the supernovae brightness is also uncertain: the initial heat due to the explosion does not seem to be sufficient; the brightness can result from the diffusion of the heat through the ejected matter or can be transported more rapidly by a shock wave. A model in which the heat is produced by the pulsar seems compatible with most observations (shapes of the brightness curves and the continuum spectra, expansion velocities, temperature and luminosity at the peak, total kinetic energy) [fr

Device and performance parameters of Cu(In,Ga)(Se,S)2-based solar cells with varying i-ZnO layer thickness

International Nuclear Information System (INIS)

Macabebe, E.Q.B.; Sheppard, C.J.; Dyk, E.E. van

2009-01-01

In pursuit of low-cost and highly efficient thin film solar cells, Cu(In,Ga)(Se,S) 2 /CdS/i-ZnO/ZnO:Al (CIGSS) solar cells were fabricated using a two-step process. The thickness of i-ZnO layer was varied from 0 to 454 nm. The current density-voltage (J-V) characteristics of the devices were measured, and the device and performance parameters of the solar cells were obtained from the J-V curves to analyze the effect of varying i-ZnO layer thickness. The device parameters were determined using a parameter extraction method that utilized particle swarm optimization. The method is a curve-fitting routine that employed the two-diode model. The J-V curves of the solar cells were fitted with the model and the parameters were determined. Results show that as the thickness of i-ZnO was increased, the average efficiency and the fill factor (FF) of the solar cells increase. Device parameters reveal that although the series resistance increased with thicker i-ZnO layer, the solar cells absorbed more photons resulting in higher short-circuit current density (J sc ) and, consequently, higher photo-generated current density (J L ). For solar cells with 303-454 nm-thick i-ZnO layer, the best devices achieved efficiency between 15.24% and 15.73% and the fill factor varied between 0.65 and 0.67.

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

Energy Technology Data Exchange (ETDEWEB)

Hsu, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hust, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McClelland, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gresshoff, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2014-11-12

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

An examination of Southwest Pacific explosive cyclones, 1989 to 2009

International Nuclear Information System (INIS)

Black, M T; Pezza, A B; Kreft, P

2010-01-01

This study has assembled a climatology of Southwest Pacific explosively developing cyclones, based on the European Centre for Medium-Range Weather Forecasts' ERA-Interim reanalysis data, over the 21-year period from 1989 to 2009. The recently developed 'combined explosive' expression, a refinement of the 'relative explosive' criterion, was used to identify cyclones deemed explosive with respect to both the drop in central pressure and the climatological pressure gradient. Over the period of analysis, 47 explosive cyclones were identified within the Southwest Pacific, equating to an average of 2.2 explosive events per year. Seasonally, explosive cyclones are most frequent during the winter months, while least frequent during the summer. Two case explosive systems are briefly considered, with their corresponding measures of intensity and scale placed into climatological perspective.

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

Energetic melt-water explosions are a well-established contributor to risk for nuclear reactors, and even more so for the metal casting industry. In-depth studies were undertaken in an industry-national laboratory collaborative effort to understand the root causes of explosion triggering and to evaluate methods for prevention. The steam explosion triggering studies (SETS) facility was devised and implemented for deriving key insights into explosion prevention. Data obtained indicated that onset of base surface-entrapment induced explosive boiling-caused trigger shocks is a result of complex combination of surface wettability, type of coating (organic versus inorganic), degree of coating wearoff, existence of bypass pathways for pressure relief, charring and non-condensable gas (NCG) release potential. Of these parameters NCGs were found to play a preeminent role on explosion prevention by stabilizing the melt-water steam interface and acting as a shock absorber. The role of NCGs was experimentally confirmed using SETS for their effect on stable film boiling using a downward facing heated body through which gases were injected. The presence of NCGs in the steam film layer caused a significant delay in the transitioning of film-to-nucleate boiling. The role of NCGs on explosion prevention was thereafter demonstrated more directly by introducing molten metal drops into water pools with and without NCG bubbling. Whereas spontaneous and energetic explosions took place without NCG injection, only benign quenching occurred in the presence of NCGs. Gravimetric analyses of organic coatings which are known to prevent explosion onset were also found to release significant NCGs during thermal attack by melt in the presence of water. These findings offer a novel, simple, cost-effective technique for deriving fundamental insights into melt-water explosions as well as for explosion prevention under most conditions of interest to metal casting, and possibly for nuclear reactor

The use of light detectors to discriminate between detonation and deflagration of explosive charges

CSIR Research Space (South Africa)

Olivier, M

2015-10-01

Full Text Available It is well known that reacting explosives emit light of varying intensity across the spectrum. Measurement of this light emission could have many applications, i.a. the local or stand-off discrimination between full detonation and deflagration...

30 CFR 75.1311 - Transporting explosives and detonators.

Science.gov (United States)

2010-07-01

... noncombustible materials. (c) When explosives and detonators are transported on conveyor belts— (1) Containers of... explosives or detonators, a person shall be at each transfer point between belts and at the unloading location; and (4) Conveyor belts shall be stopped before explosives or detonators are loaded or unloaded...

29 CFR 1926.902 - Surface transportation of explosives.

Science.gov (United States)

2010-07-01

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

Design and characterization of GaN p-i-n diodes for betavoltaic devices

Science.gov (United States)

Khan, Muhammad R.; Smith, Joshua R.; Tompkins, Randy P.; Kelley, Stephen; Litz, Marc; Russo, John; Leathersich, Jeff; Shahedipour-Sandvik, Fatemeh (Shadi); Jones, Kenneth A.; Iliadis, Agis

2017-10-01

The performance of gallium nitride (GaN) p-i-n diodes were investigated for use as a betavoltaic device. Dark IV measurements showed a turn on-voltage of approximately 3.2 V, specific-on-resistance of 15.1 mΩ cm2 and a reverse leakage current of -0.14 mA/cm2 at -10 V. A clear photo-response was observed when IV curves were measured under a light source at a wavelength of 310 nm (4.0 eV). In addition, GaN p-i-n diodes were tested under an electron-beam in order to simulate common beta radiation sources ranging from that of 3H (5.6 keV average) to 63Ni (17 keV average). From this data, we estimated output powers of 53 nW and 750 nW with overall efficiencies of 0.96% and 4.4% for our device at incident electron energies of 5.6 keV and 17 keV corresponding to 3H and 63Ni beta sources respectively.

Numerical Simulation of Explosive Forming Using Detonating Fuse

Directory of Open Access Journals (Sweden)

H Iyama

2017-09-01

Full Text Available The explosive forming is a characteristic method. An underwater shock wave is generated by underwater explosion of an explosive. A metal plate is affected high strain rate by the shock loading and is formed along a metal die. Although this method has the advantage of mirroring the shape of the die, a free forming was used in this paper. An expensive metal die is not necessary for this free forming. It is possible that a metal plate is formed with simple supporting parts. However, the forming shape is depend on the shock pressure distribution act on the metal plate. This pressure distribution is able to change by the shape of explosive, a mass of explosive and a shape of pressure vessel. On the other hand, we need the pressure vessel for food processing by the underwater shock wave. Therefore, we propose making the pressure vessel by this explosive forming. One design suggestion of pressure vessel made of stainless steel was considered. However, we cannot decide suitable conditions, the mass of the explosive and the distance between the explosive and the metal plate to make the pressure vessel. In order to decide these conditions, we have tried the numerical simulation on this explosive forming. The basic simulation method was ALE (Arbitrary Laglangian Eulerian method including with Mie-Grümeisen EOS (equation of state, JWL EOS, Johnson-Cook constitutive equation for a material model. In this paper, the underwater pressure contours to clear the propagations of the underwater shock wave, forming processes and deformation velocity of the metal plate is shown and it will be discussed about those results.

Minutes of the Explosives Safety Seminar (20th) Held at OMNI international Hotel, Norfolk, Virginia on 24-26 August 1982. Volume II

Science.gov (United States)

1982-08-01

hue an mvwe old* I noe.*iy and identify by Stoc* nowm -P) Ammunition Explosives Safety 20. AGSTRACT (Conth. an rever. sid. it noeeeary wtd identify by...explosive. All tests have been monitoreo by remote television; most also used cinematography at 500 to 1000 frames per second. Figure 2 shows an

Explosion-produced ground motion: technical summary with respect to seismic hazards

Energy Technology Data Exchange (ETDEWEB)

Rodean, Howard C [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-15

perfectly elastic but anelastic. If an underground explosion is spherical and the surrounding medium is homogeneous and isotropic, only compressional or P waves are generated. This is an idealization; both P and shear or S waves are produced, with P waves being predominant. The interaction of these waves with the inhomogeneities within the earth and the free surface of the earth produce additional reflected and refracted P and S waves, plus Rayleigh (or R) and Love (or L) waves that travel along the surface. As a consequence, the surface ground motion at a location where seismic damage is of concern is a complex mixture of several types of waves: some are generated in the vicinity of the explosion, and others at various points along different propagation paths. They arrive at different times because of different propagation velocities and transmission paths. In addition, the surface or receiver response to these waves is a function of local geology; e. g., the least severe motion occurs on hard rock. The problem of seismic motion pertinent to property damage is therefore very complicated because the damage-producing part of the wave train does not appear to be the first arrival but some subsequent portion. There may be some valid correlations between damage (i.e., architectural like cracked plaster as well as structural) and measured values of frequency-dependent displacement, velocity, and acceleration; but it is not known which waves are associated with these measurements. Therefore, the prediction of ground motion for seismic damage assessment is, at present, based on extrapolation of past experience and not upon calculations from the first principles of mechanics. This does not mean that these calculations are not of value in damage prediction. However, correlation between theoretical calculations and experimental measurements of ground motion will probably be on a statistical basis because it generally will be impractical to determine all pertinent details of the

Explosion-produced ground motion: technical summary with respect to seismic hazards

International Nuclear Information System (INIS)

Rodean, Howard C.

1970-01-01

perfectly elastic but anelastic. If an underground explosion is spherical and the surrounding medium is homogeneous and isotropic, only compressional or P waves are generated. This is an idealization; both P and shear or S waves are produced, with P waves being predominant. The interaction of these waves with the inhomogeneities within the earth and the free surface of the earth produce additional reflected and refracted P and S waves, plus Rayleigh (or R) and Love (or L) waves that travel along the surface. As a consequence, the surface ground motion at a location where seismic damage is of concern is a complex mixture of several types of waves: some are generated in the vicinity of the explosion, and others at various points along different propagation paths. They arrive at different times because of different propagation velocities and transmission paths. In addition, the surface or receiver response to these waves is a function of local geology; e. g., the least severe motion occurs on hard rock. The problem of seismic motion pertinent to property damage is therefore very complicated because the damage-producing part of the wave train does not appear to be the first arrival but some subsequent portion. There may be some valid correlations between damage (i.e., architectural like cracked plaster as well as structural) and measured values of frequency-dependent displacement, velocity, and acceleration; but it is not known which waves are associated with these measurements. Therefore, the prediction of ground motion for seismic damage assessment is, at present, based on extrapolation of past experience and not upon calculations from the first principles of mechanics. This does not mean that these calculations are not of value in damage prediction. However, correlation between theoretical calculations and experimental measurements of ground motion will probably be on a statistical basis because it generally will be impractical to determine all pertinent details of the

iPad and computer devices in preschool : A tool for literacy development among teachers and children in preschool

OpenAIRE

Oladunjoye, Olayemi Kemi

2013-01-01

The title of this thesis is "iPad and Computer devices in Preschool: A tool for literacy development among teachers and children in preschool." The study was an exploration of how teachers and their pupils put iPad and other computer devices into use in early childhood education. This study was a qualitative research study, based on the observation of the pupils and the interviews of the teachers. In this study, observation of the children and interviewing of the teachers over a period of fiv...

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...

Investigation on energetics of ex-vessel vapor explosion based on spontaneous nucleation fragmentation

International Nuclear Information System (INIS)

Liu, Jie; Koshizuka, Seiichi; Oka, Yoshiaki

2002-01-01

A computer code PROVER-I is developed for propagation phase of vapor explosion. A new thermal fragmentation model is proposed with three kinds of time scale for modeling instant fragmentation, spontaneous nucleation fragmentation and normal boiling fragmentation. The energetics of ex-vessel vapor explosion is investigated based on different fragmentation models. A higher pressure peak and a larger mechanical energy conversion ratio are obtained by spontaneous nucleation fragmentation. A smaller energy conversion ratio results from normal boiling fragmentation. When the delay time in thermal fragmentation model is near 0.0 ms, the pressure propagation behavior tends to be analogous with that in hydrodynamic fragmentation. If the delay time is longer, pressure attenuation occurs at the shock front. The high energy conversion ratio (>4%) is obtained in a small vapor volume fraction together with spontaneous nucleation fragmentation. These results are consistent with fuel-coolant interaction experiments with alumina melt. However, in larger vapor volume fraction conditions (α υ >0.3), the vapor explosion is weak. For corium melt, a coarse mixture with void fraction of more than 30% can be generated in the pre-mixing process because of its physical properties. In the mixture with such a high void fraction the energetic vapor explosion hardly takes place. (author)

Blasting and Blast Effects in Cold Regions. Part 3. Explosions in Ground Materials

Science.gov (United States)

1989-05-01

121- York, Ontario: Technical Marketing Services- 123. Explosives, Canadian Industries, 6th edition. Gaffney, E.S. (1984b) Hugoniot of water ice. In...Mines, blasting. U.S. Bureau of Nlines , Report of Insesti- Report of lnsestigations RI 7751. gations 8507. Piekutoiski. A.J. (1974) I.aborator,, scale

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

International Nuclear Information System (INIS)

Nutt, G.L.

1991-01-01

This papent describes a method for suppressing the tendency of a porous solid high explosive to ignite and detonate. It comprises: filling substantially all the press of the solid high explosive material with a predetermined pore radius of at least 10μm with a relatively inert, stable, pore filling material in liquid form, the pore filling being selected from gallium, rubidium-potassium eutectic, and Wood's metal; and solidifying the pore filling material in the pores of the explosive material

Contained fission explosion breeder reactor system

International Nuclear Information System (INIS)

Juhl, N.H.; Marwick, E.F.

1983-01-01

A reactor system for producing useful thermal energy and valuable isotopes, such as plutonium-239, uranium-233, and/or tritium, in which a pair of sub-critical masses of fissile and fertile actinide slugs are propelled into an ellipsoidal pressure vessel. The propelled slugs intercept near the center of the chamber where the concurring slugs become a more than prompt configuration thereby producing a fission explosion. Re-useable accelerating mechanisms are provided external of the vessel for propelling the slugs at predetermined time intervals into the vessel. A working fluid of lean molten metal slurry is injected into the chamber prior to each explosion for the attenuation of the explosion's effects, for the protection of the chamber's walls, and for the absorbtion of thermal energy and debris from the explosion. The working fluid is injected into the chamber in a pattern so as not to interfere with the flight paths of the slugs and to maximize the concentration of working fluid near the chamber's center. The heated working fluid is drained from the vessel and is used to perform useful work. Most of the debris from the explosion is collected as precipitate and is used for the manufacture of new slugs

Bulk-loaded emulsion explosives technology

Energy Technology Data Exchange (ETDEWEB)

Borg, D.G. [Blasting Analysis International, Inc., Allentown, PA (United States)

1995-01-01

The largest use of emulsion explosives and emulsion-Anfo blends is in surface mining operations. An emulsion explosive is a two-phase system: the inner phase is madeup of an oxidizer solution; the outer phase is made up of oils or an oil/wax blend. Emulsion Anfo blends have been used to expand drill patterns, increase fragmentation, and provide extra energy for blast casting. 3 tabs.

Regional moment: Magnitude relations for earthquakes and explosions

Energy Technology Data Exchange (ETDEWEB)

Patton, H.J.; Walter, W.R. (Lawrence Livermore National Lab., CA (United States))

1993-02-19

The authors present M[sub o]:m[sub b] relations using m[sub b](P[sub n]) and m[sub b](L[sub g]) for earthquakes and explosions occurring in tectonic and stable areas. The observations for m[sub b](P[sub n]) range from about 3 to 6 and show excellent separation between earthquakes and explosions on M[sub o]:m[sub b] plots, independent of the magnitude. The scatter in M[sub o]:M[sub b] observations for NTS explosions is small compared to the earthquake data. The M[sub o]:m[sub b](L[sub g]) data for Soviet explosions overlay the observations for US explosions. These results, and the small scatter for NTS explosions, suggest weak dependence of M[sub o]:m[sub b] relations on emplacement media. A simple theoretical model is developed which matches all these observations. The model uses scaling similarity and conservation of energy to provide a physical link between seismic moment and a broadband seismic magnitude. Three factors, radiation pattern, material property, and apparent stress, contribute to the separation between earthquakes and explosions. This theoretical separation is independent of broadband magnitude. For US explosions in different media, the material property and apparent stress contributions are shown to compensate for one another, supporting the observations that M[sub o]:M[sub b] is nearly independent of source geology. 19 refs., 2 figs., 1 tab.

Mobile authentication and access: any time, any place, any device?

Directory of Open Access Journals (Sweden)

Mark Williams

2012-11-01

Full Text Available The move from IP-based authentication to that of federated access has seen the sector support single sign-on to web-based resources, but the simplified user experience is at risk due to the rapid growth of mobile platforms and increasing variety of accompanying access methods for such devices. The user authentication experience on mobile devices is often further complicated by the poor discovery and delivery design of websites. While the introduction of tools such as Raptor permit accurate tracking of usage statistics via the UK Access Management Federation, the variety of mobile authentication methods such as native apps on devices and device paring pose additional challenges to librarians trying to gather a complete picture of resource use within their institution. In this article we examine the access challenges posed by the explosion of mobile device use.

Ultraviolet Resonant Raman Enhancements in the Detection of Explosives

Energy Technology Data Exchange (ETDEWEB)

Short Jr., Billy Joe [Naval Postgraduate School, Monterey, CA (United States)

2009-06-01

Raman-based spectroscopy is potentially militarily useful for standoff detection of high explosives. Normal (non-resonance) and resonance Raman spectroscopies are both light scattering techniques that use a laser to measure the vibrational spectrum of a sample. In resonance Raman, the laser is tuned to match the wavelength of a strong electronic absorbance in the molecule of interest, whereas, in normal Raman the laser is not tuned to any strong electronic absorbance bands. The selection of appropriate excitation wavelengths in resonance Raman can result in a dramatic increase in the Raman scattering efficiency of select band(s) associated with the electronic transition. Other than the excitation wavelength, however, resonance Raman is performed experimentally the same as normal Raman. In these studies, normal and resonance Raman spectral signatures of select solid high explosive (HE) samples and explosive precursors were collected at 785 nm, 244 nm and 229 nm. Solutions of PETN, TNT, and explosive precursors (DNT & PNT) in acetonitrile solvent as an internal Raman standard were quantitatively evaluated using ultraviolet resonance Raman (UVRR) microscopy and normal Raman spectroscopy as a function of power and select excitation wavelengths. Use of an internal standard allowed resonance enhancements to be estimated at 229 nm and 244 nm. Investigations demonstrated that UVRR provided ~2000-fold enhancement at 244 nm and ~800-fold improvement at 229 nm while PETN showed a maximum of ~25-fold at 244 nm and ~190-fold enhancement at 229 nm solely from resonance effects when compared to normal Raman measurements. In addition to the observed resonance enhancements, additional Raman signal enhancements are obtained with ultraviolet excitation (i.e., Raman scattering scales as !4 for measurements based on scattered photons). A model, based partly on the resonance Raman enhancement results for HE solutions, is presented for estimating Raman enhancements for solid HE samples.

Study of the initiation and the escalade phases of a vapour explosion; Etude de la phase d'initiation et d'escalade d'une explosion de vapeur

Energy Technology Data Exchange (ETDEWEB)

Lamome, J

2007-09-15

The steam explosion triggering issue is discussed here by studying at the thermal fragmentation (small pressure perturbation) of a hot water droplet surrounded by a stable steam film. Fragmentation seems to be the consequence of local contacts between the droplet and the coolant. However, the exact mechanism altering the droplet following the above mentioned contacts is uncertain. After a study of the proportions in place, we realized a contact can fragment the droplet in a very short period of time. Therefore, we adopted an approach considering the contact as the explosion criteria. In order to validate this approach, we researched the explosion levels of the experimental variations based on the surrounding pressure and on the coolant's temperature. The model found again the experimental variations, the levels were found again with some uncertainty. The contact is obtained by 2 mechanisms inducing liquid's proximity: a steam film global compression due to the disturbance and the amplification of the interface defaults between the coolant and the steam. It appears it is the mechanism of global compression that explains mostly the experimental variations. Following these results, we conducted model's extrapolations in order to come as close as possible of the conditions in which steam explosion can occur on an industrial scale (i.e. in the water pressured nuclear reactors). (author)

Explosion-proof lighting units according to EC standards

Energy Technology Data Exchange (ETDEWEB)

Olenik, H; Weyer, K

1982-03-01

Electrical equipment, e.g. lights, may be the cause of ignition in explosive atmospheres unless special measures are taken to prevent ignition. For an exact definition and description of explosion protection measures, the German VDE regulations contain specifications for construction and testing. There is a special administrative procedure to ensure that these explosion protection measures are checked by an official testing authority and that electrical equipment will receive a certificate of its suitability for explosive environments. The construction specifications have been elaborated by a VDE commission and are constantly updated.

Dimensional analysis of small-scale steam explosion experiments

International Nuclear Information System (INIS)

Huh, K.; Corradini, M.L.

1986-01-01

Dimensional analysis applied to Nelson's small-scale steam explosion experiments to determine the qualitative effect of each relevant parameter for triggering a steam explosion. According to experimental results, the liquid entrapment model seems to be a consistent explanation for the steam explosion triggering mechanism. The three-dimensional oscillatory wave motion of the vapor/liquid interface is analyzed to determine the necessary conditions for local condensation and production of a coolant microjet to be entrapped in fuel. It is proposed that different contact modes between fuel and coolant may involve different initiation mechanisms of steam explosions

77 FR 55108 - Explosive Siting Requirements

Science.gov (United States)

2012-09-07

... energy, or a chemical explosion requiring a chemical reaction. Furthermore, an accident may happen... for energetic liquids. \\4\\ Crowl, D.A., Understanding Explosions, AIAA Center for Chemical Process... chemical hazards of energetic liquids used at commercial launch sites. Finally, a site map must now be at a...

Multi-scale fracture damage associated with underground chemical explosions

Science.gov (United States)

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

2018-05-01

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

Influence of surface finish on the plasma formation at the skin explosion

International Nuclear Information System (INIS)

Datsko, I M; Chaikovsky, S A; Labetskaya, N A; Rybka, D V; Oreshkin, V I; Khishchenko, K V

2016-01-01

The paper reports on experiments to investigate how the quality of surface finish, i.e., surface roughness, influences the plasma formation in a skin explosion of conductors. The experiments were performed on a MIG terawatt generator with a current amplitude of up to 2.5 MA and current rise time of 100 ns. The plasma formation at the conductor surface and the evolution of the plasma boundary was recorded using a four-frame optical camera with an exposure time of 3 ns per frame. It is shown that the quality of surface finish little affects the onset of plasma formation in a skin explosion of stainless steel and St3 steel conductors at a magnetic field of up to 400 T. (paper)

The concept of explosives malfunctioning in rock blasting

Energy Technology Data Exchange (ETDEWEB)

Liu, Q.

1993-11-01

The purpose is to identify the critical conditions that cause malfunctioning for some commonly used explosives. Experiments are described that measure sympathetic detonation, desensitization, and cut-offs for two variables: spacing and delay. Explosive malfunctioning is depicted on a delay spacing chart that has different regions. On the chart, the shape and size of each region can vary from one explosive to another. Results are presented from over 70 blasts, that were conducted in the underground drift at the CANMET Experimental Mine, to identify the malfunctioning characteristics of specific emulsion, water gel, and dynamite explosives. For each experiment, two parallel blastholes (with diameter of 32 mm and depth of 1.7 m) were drilled downwards, and full coupling was achieved. The results are presented for the three types of explosives tested. 11 refs., 7 figs.

Identification of homemade inorganic explosives by ion chromatographic analysis of post-blast residues.

Science.gov (United States)

Johns, Cameron; Shellie, Robert A; Potter, Oscar G; O'Reilly, John W; Hutchinson, Joseph P; Guijt, Rosanne M; Breadmore, Michael C; Hilder, Emily F; Dicinoski, Greg W; Haddad, Paul R

2008-02-29

Anions and cations of interest for the post-blast identification of homemade inorganic explosives were separated and detected by ion chromatographic (IC) methods. The ionic analytes used for identification of explosives in this study comprised 18 anions (acetate, benzoate, bromate, carbonate, chlorate, chloride, chlorite, chromate, cyanate, fluoride, formate, nitrate, nitrite, perchlorate, phosphate, sulfate, thiocyanate and thiosulfate) and 12 cations (ammonium, barium(II), calcium(II), chromium(III), ethylammonium, magnesium(II), manganese(II), methylammonium, potassium(I), sodium(I), strontium(II), and zinc(II)). Two IC separations are presented, using suppressed IC on a Dionex AS20 column with potassium hydroxide as eluent for anions, and non-suppressed IC for cations using a Dionex SCS 1 column with oxalic acid/acetonitrile as eluent. Conductivity detection was used in both cases. Detection limits for anions were in the range 2-27.4ppb, and for cations were in the range 13-115ppb. These methods allowed the explosive residue ions to be identified and separated from background ions likely to be present in the environment. Linearity (over a calibration range of 0.05-50ppm) was evaluated for both methods, with r(2) values ranging from 0.9889 to 1.000. Reproducibility over 10 consecutive injections of a 5ppm standard ranged from 0.01 to 0.22% relative standard deviation (RSD) for retention time and 0.29 to 2.16%RSD for peak area. The anion and cation separations were performed simultaneously by using two Dionex ICS-2000 chromatographs served by a single autoinjector. The efficacy of the developed methods was demonstrated by analysis of residue samples taken from witness plates and soils collected following the controlled detonation of a series of different inorganic homemade explosives. The results obtained were also confirmed by parallel analysis of the same samples by capillary electrophoresis (CE) with excellent agreement being obtained.

Mesoscale modeling of metal-loaded high explosives

Energy Technology Data Exchange (ETDEWEB)

Bdzil, John Bohdan [Los Alamos National Laboratory; Lieberthal, Brandon [UNIV OF ILLINOIS; Srewart, Donald S [UNIV OF ILLINOIS

2010-01-01

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

Progress in the development of explosives materials detectors

International Nuclear Information System (INIS)

Williams, W.D.; Conrad, F.J.; Sandlin, L.L.; Burrows, T.A.

1978-01-01

Five hand-held explosives vapor detectors (Elscint Model EXD-2, ITI Model 70, Leigh-Marsland Model S-201, Pye Dynamics Model PD.2.A, and Xonics Model GC-710) were evaluated for sensitivity to a variety of explosives, identification of false alarm agents, and general performance and maintenance characteristics. The results of this evaluation, as presented, indicate that there is no single explosives detector which is best-suited for use at all nuclear facilities. Rather, there are several site-specific elements which must be considered when choosing an explosives detector. There are several new explosives detector technologies being developed which will out-perform existing commercial equipment. Some of these new detectors may be commercially available by the end of fiscal year 1980 and will be cost-effective to purchase and operate. The following areas of explosives detection research are discussed: nitrogen-phosphorous detectors, plasma chromatography, mass spectroscopy, small animal olfactory, vapor preconcentration, nuclear quadrupole resonance, far infrared radiation imaging, nuclear magnetic resonance, thermal neutron activation, and computerized tomography

Luck Reveals Stellar Explosion's First Moments

Science.gov (United States)

2008-05-01

-rays came from one of the galaxy's spiral arms. Soderberg led a 38-person international scientific team that quickly began an intensive effort to study the new object using both orbiting and ground-based telescopes. In order to conclude that they had, in fact, seen the predicted early burst of X-rays from a supernova, they needed to eliminate alternative explanations, such as a gamma-ray burst, and then to show that, as time went on, the object behaved like a normal supernova. The scientists scrutinized the object with Swift's gamma-ray instrument, the Chandra X-ray Observatory, and the Hubble Space Telescope. On the ground, they used the Gemini North telescope and the Keck I telescope in Hawaii, the 200-inch and 60-inch telescopes at Palomar Observatory in California, the 3.5-meter telescope at Apache Point Observatory in New Mexico, and the National Science Foundation's Very Large Array (VLA) and Very Long Baseline Array (VLBA) radio telescopes. The VLA and VLBA provided key information that showed the object evolving in a pattern similar to other supernovae. "The data from all these telescopes confirmed that what we were seeing is indeed a supernova and not some new type of object. That initial X-ray burst thus is the earliest observation ever of an exploding star," Soderberg said. The scientists are excited at the prospects of learning vital new details that will help them settle longstanding controversies about the mechanisms of supernova explosions. Stars much more massive than our Sun end their lives in supernova explosions, as they run out of fuel for the thermonuclear reactions that power them. With no more energy being released at the star's core, the core collapses. Further collapse of the star is thought to cause a violent rebound that blasts most of the stars's material into space. What remains is a superdense neutron star or a black hole. The details of this scenario, however, are not well understood, and astronomers differ over the exact mechanisms. Much of

Nuclear Explosions 1945-1998