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1

27 CFR 555.180 - Prohibitions relating to unmarked plastic explosives.  

Code of Federal Regulations, 2010 CFR

...false Prohibitions relating to unmarked plastic explosives. 555.180 Section 555... COMMERCE IN EXPLOSIVES Marking of Plastic Explosives § 555.180 Prohibitions relating to unmarked plastic explosives. (a) No person...

2010-04-01

2

27 CFR 555.180 - Prohibitions relating to unmarked plastic explosives.  

Code of Federal Regulations, 2011 CFR

...true Prohibitions relating to unmarked plastic explosives. 555.180 Section 555... COMMERCE IN EXPLOSIVES Marking of Plastic Explosives § 555.180 Prohibitions relating to unmarked plastic explosives. (a) No person...

2011-04-01

3

Plastic explosives Mike Hopkins  

E-print Network

Plastic explosives Mike Hill Mike Hopkins Doug Ravenel What this talk is about The poster The HHRH The reduced E4 -term 1.1 Plastic explosives: A C4 analog of the Kervaire invariant calculation Conference of Virginia Mike Hopkins Harvard University Doug Ravenel University of Rochester #12;Plastic explosives Mike

Ravenel, Douglas

4

27 CFR 555.181 - Reporting of plastic explosives.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2010-04-01 true Reporting of plastic explosives. 555.181 Section 555.181...EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of Plastic Explosives § 555.181 Reporting of plastic explosives. All persons, other...

2011-04-01

5

27 CFR 555.181 - Reporting of plastic explosives.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Reporting of plastic explosives. 555.181 Section 555.181...EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of Plastic Explosives § 555.181 Reporting of plastic explosives. All persons, other...

2010-04-01

6

Fluorine analysis of plastic-bonded explosives and plastics  

Microsoft Academic Search

A method for the analysis of 25 to 200 mg of fluorine in highly fluorinated plastics and plastic-bonded explosives is presented. Up to 1 g of the explosive is burned by the oxygen bomb technique. The polymers are burned with an excess of paraffin fuel. After removal of carbon dioxide from the combustion products, fluorine is determined gravimetrically as lithium

Walter Selig

1968-01-01

7

27 CFR 555.181 - Reporting of plastic explosives.  

Code of Federal Regulations, 2012 CFR

...2010-04-01 true Reporting of plastic explosives. 555.181 Section 555.181 Alcohol...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of...

2012-04-01

8

27 CFR 555.181 - Reporting of plastic explosives.  

...2014-04-01 false Reporting of plastic explosives. 555.181 Section 555.181 Alcohol...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of...

2014-04-01

9

27 CFR 555.181 - Reporting of plastic explosives.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Reporting of plastic explosives. 555.181 Section 555.181 Alcohol...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of...

2013-04-01

10

Dynamic Mechanical Analysis of Plastic Bonded Explosives  

Microsoft Academic Search

Aging processes that change the mechanical properties of the binder of plastic bonded explosives (PBX) could have a significant effect on the composite mechanical properties. It is essential to understand how the binder ages; however, it is more realistic to test the change of mechanical properties of aging PBX. Because PBX's and Mocks have only a small amount of binder,

Mary S. Campbell

11

Microstructural Characterization of Plastic Bonded Explosives  

Microsoft Academic Search

Plastic bonded explosives (PBX), a mixture of hard, anisotropic grains in a compliant matrix, represent an interesting case for understanding composite mechanical response and failure. PBX 9501 (0.95 cyclotetramethylene tetranitramine [HMX], 0.05 polymer binder) is relatively safe formulation of HMX, which is thought to be due to the high compliance of the binder. Crack formation between the crystals and the

John Yeager; Daniel Hooks; David Bahr

2010-01-01

12

Decomposition of Nitroplasticizer in Plastic Bonded Explosive PBX 9501  

Microsoft Academic Search

In the plastic bonded explosive PBX 9501, a 50\\/50 mixture of Estane 5703 (a polyester urethane random copolymer) and nitroplasticizer (NP) binds the HMX explosive crystals. Chemical kinetic mechanisms are being developed for the thermal degradation of NP for high temperatures (explosions) and low temperatures (natural and accelerated aging studies). The goal of this work is to investigate reaction mechanisms

D. K. Pauler; J. D. Kress; J. M. Lightfoot; L. Woods; B. G. Russell

2006-01-01

13

Fatigue of lx-14 and lx-19 plastic bonded explosives  

Microsoft Academic Search

The DOD uses the plastic bonded explosive (PBX) LX-14 in a wide variety of applications including shaped charges and explosively formed projectiles. LX-19 is a higher energy explosive, which could be easily substituted for LX-14 because it contains the identical Estane 5703p binder and more energetic CL-20 explosive. Delivery systems for large shaped charges, such as TOE 2, include the

D. Mark Hoffman

2000-01-01

14

Fatigue of LX14 and LX19 plastic bonded explosives  

Microsoft Academic Search

The DOD uses the plastic bonded explosive (PBX) LX-14 in a wide variety of applications including shaped charges and explosively forged projectiles. LX- 19 is a higher energy explosive, which could be easily substituted for LX-14 because it contains the identical Estane 5703p binder and more energetic CL-20 explosive. Delivery systems for large shaped charges, such as TOW-2, include the

Hoffman

1998-01-01

15

Microstructural Characterization of Plastic Bonded Explosives  

NASA Astrophysics Data System (ADS)

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

Yeager, John; Hooks, Daniel; Bahr, David

2010-03-01

16

Comparison of constitutive models for plastic-bonded explosives  

Microsoft Academic Search

A constitutive model for an explosive consists of three parts: equation of state of reactants, equation of state of products, and reaction rate. In the absence of a good physical theory, models are empirical and based on heuristics. For the HMX based plastic-bonded explosive PBX 9501, three models have previously been calibrated and used in numerical simulations. Here, these three

Ralph Menikoff

2008-01-01

17

A parametric pressing study using a plastic-bonded explosive  

SciTech Connect

Pressed plastic-bonded explosives, PBXs, are commonly used by defense and private industry. PBX 9501 is composed of HMX crystals held together with a plastic binder 'softened' with plasticizers. The detonation behavior of any explosive is very dependent upon its density, with the desire to have a uniform, high density throughout the explosive component. A parametric study has been performed pressing PBX 9501 hydrostatically and uniaxially. The effects of several pressing parameters on the bulk density and density profile, as well as mechanical properties, have been measured. The parameters investigated include pressure, temperature, number of cycles, dwell time, rest time, sack thickness, and particle distribution and size. Density distributions within the pressed explosives were also compared.

Hayden, D. J. (David J.); Maez, L. R. (Leland R.); Olinger, B. W. (Barton W.); Powell, S. J. (Sandra J.)

2002-01-01

18

27 CFR 555.183 - Importation of plastic explosives on or after April 24, 1997.  

...2014-04-01 false Importation of plastic explosives on or after April 24, 1997. 555.183...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of...

2014-04-01

19

27 CFR 555.183 - Importation of plastic explosives on or after April 24, 1997.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Importation of plastic explosives on or after April 24, 1997. 555.183...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of...

2013-04-01

20

27 CFR 555.183 - Importation of plastic explosives on or after April 24, 1997.  

Code of Federal Regulations, 2012 CFR

...2010-04-01 true Importation of plastic explosives on or after April 24, 1997. 555.183...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of...

2012-04-01

21

Aktau Plastics Plant Explosives Material Report  

SciTech Connect

The U.S. Department of Energy (DOE) has been cooperating with the Republic of Kazakhstanin Combined Threat Reduction (CTR) activities at the BN350 reactor located at the Mangyshlak Atomic Energy Complex (MAEC) in the city of Aktau, Kazakhstan since 1994. DOE contract personnel have been stationed at this facility for the last two years and DOE representatives regularly visit this location to oversee the continuing cooperative activities. Continued future cooperation is planned. A Russian news report in September 1999 indicated that 75 metric tons of organic peroxides stored at the Plastics Plant near Aktau were in danger of exploding and killing or injuring nearby residents. To ensure the health and safety of the personnel at the BN350 site, the DOE conducted a study to investigate the potential danger to the BN350 site posed by these materials at the Plastics Plant. The study conclusion was that while the organic peroxides do have hazards associated with them, the BN350 site is a safe distance from the Plastics Plant. Further, because the Plastics Plant and MAEC have cooperative fire-fighting agreements,and the Plastics Plant had exhausted its reserve of fire-fighting foam, there was the possibility of the Plastics Plant depleting the store of fire-fighting foam at the BN350 site. Subsequently, the DOE decided to purchase fire-fighting foam for the Plastics Plant to ensure the availability of free-fighting foam at the BN350 site.

CASE JR.,ROGER S.

1999-12-01

22

Microstructural characterization of simulated plastic-bonded explosives  

NASA Astrophysics Data System (ADS)

Plastic-bonded explosives (PBX) are highly complex molecular composites. Recent mechanical investigations of PBX properties, in particular deformation and failure under uniaxial and cyclic loading, have revealed microstructure-dependent fracture behavior. A methodology of characterizing the relationship between microstructure and mechanical properties of PBX materials has been developed and tested on simulated materials with particular focus on the interface. Synchrotron X-ray studies of molecular crystals, explosive binders and formulated simulant composites revealed some intriguing possibilities in real-time observation of cracks, bubbles, delamination, and void collapse during high-speed loading events. A surface energy and thermomechanical study of several molecular crystals, including explosives, and potential binder candidates revealed thermodynamic interactions were not likely to be more important than mechanical properties for insensitive explosives. Ellipsometry and neutron reflectometry were used to identify the interfacial structure of polymer-acetaminophen (an explosive simulant) composites. The crystal-polymer interfacial structure was altered by inclusion of a plasticizing agent -- an important result considering the commonality of plasticizing polymers in PBX formulation. The difference in interfacial properties was also observed mechanically with nanoindentation. Specifically, the plasticizer inhibited formation of a large, diffuse interface / interphase and resulted in a composite which was more likely to experience film delamination than the non-plasticized composite. The difference in mechanical behavior caused by the difference in interfacial structure has important implications for crack initiation and explosive sensitivity. Additionally, certain crystalbinder composites were investigated with a new delamination test, which, while preliminary, resulted in additional insights into fracture behavior. The methodology presented herein provides a pathway for studying PBXs, or similar composites, from the nano-scale to the macro-scale, both in terms of structure and processing, and shows important relationships between interfacial properties and mechanical behavior.

Yeager, John David

2011-12-01

23

Mechanical modeling of the plastic bonded explosive LX17  

E-print Network

The current research attempts to develop a model for a polycrystalline, composite solid with viscoelastic matrix known as LX17. It is a highly-filled plastic bonded explosive with a shelf-life of up to 50 years. Experimentation is too costly...

Clayton, Kyle Martin

2012-06-07

24

Decomposition of Nitroplasticizer in Plastic Bonded Explosive PBX 9501  

NASA Astrophysics Data System (ADS)

In the plastic bonded explosive PBX 9501, a 50/50 mixture of Estane 5703 (a polyester urethane random copolymer) and nitroplasticizer (NP) binds the HMX explosive crystals. Chemical kinetic mechanisms are being developed for the thermal degradation of NP for high temperatures (explosions) and low temperatures (natural and accelerated aging studies). The goal of this work is to investigate reaction mechanisms using density functional electronic structure theory in addition to the data obtained from explosion and aging experiments. Very little is known of the mechanisms for the oxidation of polymers by oxidants other than molecular oxygen. As the first step in the aging of PBX 9501 in a low moisture and low oxygen environment, we propose that NP decomposes into oxidizing gases (NO2 and NO).

Pauler, D. K.; Kress, J. D.; Lightfoot, J. M.; Woods, L.; Russell, B. G.

2006-07-01

25

Dynamic Fracture Behavior of Plastic-Bonded Explosives  

NASA Astrophysics Data System (ADS)

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

Fu, Hua; Li, Jun-Ling; Tan, Duo-Wang

2011-06-01

26

Fatigue of LX-14 and LX-19 plastic bonded explosives  

SciTech Connect

The DOD uses the plastic bonded explosive (PBX) LX-14 in a wide variety of applications including shaped charges and explosively forged projectiles. LX- 19 is a higher energy explosive, which could be easily substituted for LX-14 because it contains the identical Estane 5703p binder and more energetic CL-20 explosive. Delivery systems for large shaped charges, such as TOW-2, include the Apache helicopter. Loads associated with vibrations and expansion from thermal excursions in field operations may, even at low levels over long time periods, cause flaws, already present in the PBX to grow. Flaws near the explosive/liner interface of a shaped charge can reduce performance. Small flaws in explosives are one mechanism (the hot spot mechanism) proposed for initiation and growth to detonation of PBXs like LX-14, PBXN 5, LX-04 and LX-17 among others. Unlike cast-cured explosives and propellants, PBXs cannot usually be compression molded to full density. Generally, the amount of explosive ignited by a shock wave is approximately equal to the original void volume. Whether or not these flaws or cracks grow during field operations to an extent sufficient to adversely affect the shaped charge performance or increase the vulnerability of the PBX is the ultimate question this effort could address. Currently the fatigue life of LX-14 under controlled conditions is being studied in order to generate its failure stress as a function of the number of fatigue cycles (S- N curve). Proposed future work will address flaw and crack growth and their relationship to hot-spot concentration and explosive vulnerability to shock and/or fragment initiation.

Hoffman, D. M., LLNL

1998-04-23

27

Thermal analyses for quality control of plastics, ceramics, and explosives  

SciTech Connect

Thermal analyses are performed for production quality control (q.c.) and for surveillance at Mound on plastic, ceramic, explosive and pyrotechnic materials. For the weapons surveillance program, weapon components are disassembled after varying times in the field; thermal and other analyses are then performed on the component materials. The types of thermal analyses done include: differential scanning calorimetry (DSC), differential thermal analysis (DTA), thermogravimetry (TG), thermomechanical analysis (TMA), and high temperature TG/DTA. 5 refs., 4 figs.

Brown, C.R.; Garrod, M.J.; Whitaker, R.B.

1990-01-01

28

On the Unreacted Hugoniots of Three Plastic Bonded Explosives  

NASA Astrophysics Data System (ADS)

There is a continuing interest in determining the detonation characteristics of loaded plastic-bonded explosives (PBXs). The UK licensing agency for explosives, DOSG, wishes to better understand the response of insensitive high explosives. This has required more detailed investigation of the transit of reaction from the unreacted state to products. The starting condition, before application of a kinetic scheme to describe reaction, is thus the unreacted Hugoniot for the material. In this work three PBXs, manufactured by BAE Land Systems, are investigated and modelled. All contain RDX in differing quantities in an HTPB binder. One of them contains aluminium. Two of the materials have the same weight percentage of filler and binder but differ in the grain size distribution entrained. The experimental Hugoniots are presented, and a composite equation of state is derived using an engineering model and shown to describe the measurements well. Further applications of the technique are described and future uses are outlined.

Milne, A. M.; Bourne, N. K.; Millett, J. C. F.

2006-07-01

29

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

Microsoft Academic Search

There are concerns about the lifetime of the nation`s stockpile of high explosives (HEs) and their components. The DOE`s Core Surveillance and Enhanced Surveillance programs specifically target degradation of HE, binders, and plastic-bonded explosives (PBXs) for determination of component lifetimes and handling procedures. The principal goal of this project is to identify the decomposition mechanisms of HEs, plasticizers, and plastic

Caroline E. Burgess; James D. Woodyard; K. A. Rainwater; J. M. Lightfoot; B. R. Richardson

1998-01-01

30

Decomposition of Nitroplasticizer in Plastic Bonded Explosive PBX 9501  

NASA Astrophysics Data System (ADS)

In the plastic bonded explosive PBX 9501, a 50/50 mixture of Estane 5703, a polyester urethane random copolymer, and nitroplastizer (NP) binds the HMX explosive crystals. Chemical kinetic mechanisms are being developed for the thermal degradation of NP for high temperatures (explosions) and low temperatures (natural and accelerated aging studies). The goal of this work is to investigate reaction mechanisms using density functional electronic structure theory in addition to the data obtained from explosion and aging experiments. NP consists of a 50/50 mixture of bis-2,2-dinitropropyl acetal and formal. Using 2,2-dinitro-1-methoxypropane as a model compound, a library of reactions was investigated to propose a mechanism for the decomposition of NP. The current mechanism begins with the elimination of HONO, which remains trapped within the material. HONO then adds onto the backbone of NP, which can lead to the formation of esters and oximes that may react further to produce carbon monoxide, carbon dioxide, and NOx gases. This work is supported by the Enhanced Surveillance Campaign and the Advanced Simulation and Computing program.

Pauler, Denise

2005-07-01

31

Dynamic mechanical signatures of aged LX17-1 plastic bonded explosive  

Microsoft Academic Search

The complex shear modulus of the plastic bonded explosive (PBX) LX-17-1 from stockpile returns, core tests and historical billets was measured over the temperature range from ?150 to 120°C at five frequencies from 0.1 to 10 Hz. LX-17-1 is composed of 92.5% insensitive high explosive triaminotrinitro-benzene (TATB) and 7.5% plastic binder, KF-800. Three relaxations were observed as peaks in the

D. Mark Hoffman

2001-01-01

32

Atomistic studies of RDX and FOX7 Based Plastic-Bonded explosives: molecular dynamics simulation  

Microsoft Academic Search

Molecular dynamics simulations were carried out to study the effects of interface interactions between a crystalline structure and a plastic bonded explosive (PBX) system. In this work, the hydroxyl-terminated polybutadiene (HTPB) represents the polymer, isophorone diisocyanate (IPDI) is the diisocyanate and dioctyl adipate (DOA) is the plasticizer. Two different crystal high explosives components were used, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), which is characterized

Mounir Jaidann; Hakima Abou-Rachid; Xavier Lafleur-Lambert; Josée Brisson

2011-01-01

33

Plastic explosive RDX: Cyclotrimethylenetrinitramine. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the properties and handling of plastics explosive RDX. Production, decomposition, toxicology studies, and desensitizing techniques are discussed. RDX detection in munitions plant wastewater and air samples is described along with methods of eliminating this explosive from the effluent. Molecular dynamics, sensitivity to shock and heat, burning behavior, and explosion velocity are presented. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

NONE

1996-12-01

34

Plastic explosive RDX: Cyclotrimethylenetrinitramine. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the properties and handling of plastics explosive RDX. Production, decomposition, toxicology studies, and desensitizing techniques are discussed. RDX detection in munitions plant wastewater and air samples is described along with methods of eliminating this explosive from the effluent. Molecular dynamics, sensitivity to shock and heat, burning behavior, and explosion velocity are presented. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

NONE

1995-10-01

35

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

Microsoft Academic Search

Various plastic bonded explosives (PBXs) contain about 5wt.% polymer, plasticizer, and stabilizer as binder. The glass-transition temperature (Tg) determines, in part, if the binder will reduce or increase the sensitivity of the PBX to impact. A soft binder reduces the impact sensitivity; however, too soft a binder compromises the mechanical strength below that desirable for dimensional stability. Glass transitions were

Mary Stinecipher Campbell; Danielle Garcia; Deanne Idar

2000-01-01

36

Thermal properties and shelf life of HMX–HTPB based plastic-bonded explosives  

Microsoft Academic Search

Plastic-bonded explosives (PBXs) with different amounts of polymer and based on explosives with different particle size distributions have been compared for their thermal properties and shelf life. Chung Shan Institute of Science and Technology has extensive experience with the processing of hydroxyl terminated polybutadiene (HTPB)-based PBXs. The investigation showed that the shelf life of HMX-based formulations is longer than 60

Jinn-Shing Lee; Chung-King Hsu

2002-01-01

37

NQR Characteristics of an RDX Plastic Explosives Simulant.  

PubMed

For reliable detection of explosives, a combination of methods integrated within a single measurement platform may increase detection performance. However, the efficient field testing of such measurement platforms requires the use of inexplosive simulants that are detectable by a wide range of methods. Physical parameters such as simulant density, elemental composition and crystalline structure must closely match those of the target explosive. The highly discriminating bulk detection characteristics of nuclear quadrupole resonance (NQR) especially constrain simulant design. This paper describes the development of an inexplosive RDX simulant suited to a wide range of measurement methods, including NQR. Measurements are presented that confirm an RDX NQR response from the simulant. The potential use of the simulant for field testing a prototype handheld NQR-based RDX detector is analyzed. Only modest changes in prototype operation during field testing would be required to account for the use of simulant rather than real explosive. PMID:23204647

Turecek, J; Schwitter, B; Miljak, D; Stancl, M

2012-12-01

38

Development of a high-tensile-strain plastic-bonded TATB explosive  

SciTech Connect

Typical plastic-bonded explosives (PBX) with greater than 90 weight-percent explosive filler in a fluorocarbon binder have tensile strains which range from 0.2 to 0.6{percent}. We have recently developed a TATB-based PBX with a tensile strain approaching 1{percent} while maintaining a high-volume loading of the crystalline explosive component. We discuss our formulation efforts to design a TATB/poly(styrene-(ethylene-butylene)-styrene)(Kraton){sup 1} PBX and the critical processing parameters which affect the ultimate mechanical properties of this PBX. 9 refs., 3 figs., 5 tabs.

Pruneda, C.; McGuire, R.; Clements, R.

1990-04-05

39

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

Microsoft Academic Search

Various plastic bonded explosives (PBXs) contain about 5-wt% polymer, plasticizer, and stabilizer as binder. The glass-transition temperature (T{sub g}) determines, in part, if the binder will reduce or increase the sensitivity of the PBX to impact. A soft binder reduces the impact sensitivity; however, too soft a binder compromises the mechanical strength below that desirable for dimensional stability. Glass transitions

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

1998-01-01

40

HIGH PERFORMANCE MELT-CAST PLASTIC-BONDED EXPLOSIVES  

Microsoft Academic Search

DRDC Valcartier has been developing new melt-cast explosives containing nitramines, TNT and a family of energetic thermoplastic elastomers (ETPEs) based on Glycidyl Azide Polymer. It was proven that the ETPEs, added in small amounts to the TNT, modified the glassy behaviour of the compositions and created a new product that showed enough elasticity to pass mechanical Insensitive Munitions tests such

P. Brousseau; G. Ampleman; S. Thiboutot; E Diaz; S. Trudel

41

Towards Accurate Molecular Modeling of Plastic Bonded Explosives  

Microsoft Academic Search

There is substantial interest in identifying the controlling factors that influence the susceptibility of polymer bonded explosives (PBXs) to accidental initiation. Numerous Molecular Dynamics (MD) simulations of PBXs using the COMPASS force field have been reported in recent years, where the validity of the force field in modeling the solid EM fill has been judged solely on its ability to

T. L. Chantawansri; J. Andzelm; D. Taylor; E. Byrd; B. Rice

2010-01-01

42

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

SciTech Connect

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

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

1998-09-01

43

Thermal Decomposition of Plastic Bonded Explosives by Molecular Dynamic Simulations with the ReaxFF Force Field  

Microsoft Academic Search

Plastic bonded explosives (PBX) are a type of composite energetic materials in which a high explosive is dispersed in a polymer matrix. The main purpose of making such high explosive polymer bound is to reduce their sensitivity to shock, friction, impact, etc. Thermal decomposition is an essential process to characterize an energetic material, because it is one of main causes

Luzheng Zhang

2005-01-01

44

The Strength of Plastic Bonded Explosives as a Function of Pressure, Strain Rate and Temperature  

Microsoft Academic Search

Measurements as a function of strain rate and temperature have indicated the importance of the polymer binder in determining the strength of plastic bonded explosives at ambient conditions and low strain rate. Recent measurements of strength as a function of pressure further support this conclusion. As pressure or strain rate are increased or temperature is decreased the strength increases as

Donald Wiegand

2005-01-01

45

The Strength of Plastic Bonded Explosives as a Function of Pressure, Strain Rate and Temperature  

NASA Astrophysics Data System (ADS)

Measurements as a function of strain rate and temperature have indicated the importance of the polymer binder in determining the strength of plastic bonded explosives at ambient conditions and low strain rate. Recent measurements of strength as a function of pressure further support this conclusion. As pressure or strain rate are increased or temperature is decreased the strength increases as does the strength of many polymers. In addition, at relatively large values of pressure or strain rate and/or relatively low values of temperature the strength is less sensitive to changes of these quantities. These trends suggest that as the polymer binder becomes stronger with increasing pressure or strain rate or with decreasing temperature, the strength of the explosive component of these composites becomes more important in determining the strength of the composite. Results will be presented for plastic bonded explosives, e.g., LX-14, that demonstrate these trends as a function of pressure, strain rate and temperature.

Wiegand, Donald

2005-07-01

46

Towards Accurate Molecular Modeling of Plastic Bonded Explosives  

NASA Astrophysics Data System (ADS)

There is substantial interest in identifying the controlling factors that influence the susceptibility of polymer bonded explosives (PBXs) to accidental initiation. Numerous Molecular Dynamics (MD) simulations of PBXs using the COMPASS force field have been reported in recent years, where the validity of the force field in modeling the solid EM fill has been judged solely on its ability to reproduce lattice parameters, which is an insufficient metric. Performance of the COMPASS force field in modeling EMs and the polymeric binder has been assessed by calculating structural, thermal, and mechanical properties, where only fair agreement with experimental data is obtained. We performed MD simulations using the COMPASS force field for the polymer binder hydroxyl-terminated polybutadiene and five EMs: cyclotrimethylenetrinitramine, 1,3,5,7-tetranitro-1,3,5,7-tetra-azacyclo-octane, 2,4,6,8,10,12-hexantirohexaazazisowurzitane, 2,4,6-trinitro-1,3,5-benzenetriamine, and pentaerythritol tetranitate. Predicted EM crystallographic and molecular structural parameters, as well as calculated properties for the binder will be compared with experimental results for different simulation conditions. We also present novel simulation protocols, which improve agreement between experimental and computation results thus leading to the accurate modeling of PBXs.

Chantawansri, T. L.; Andzelm, J.; Taylor, D.; Byrd, E.; Rice, B.

2010-03-01

47

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

SciTech Connect

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

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

1997-10-01

48

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

Microsoft Academic Search

Molecular dynamics simulations have been performed to investigate well-known energetic material cyclotrimethylene trinitramine (RDX) crystal and RDX-based plastic-bonded explosives (PBXs) with four typical fluorine-polymers, polyvinylidenedifluoride (PVDF), polychlorotri-fluoroethylene (PCTFE), fluorine rubber (F2311), and fluorine resin (F2314). The elastic coefficients, mechanical properties, binding energies, and detonation performances are obtained for the RDX crystal and RDX-based PBXs. The results indicate that the mechanical

Wei Zhu; Jijun Xiao; Weihua Zhu; Heming Xiao

2009-01-01

49

Creep Testing Plastic-Bonded Explosives in Uni-axial Compression  

SciTech Connect

High fidelity measurements of time-dependent strain in the plastic-bonded explosives LX-17-1 and PBX 9502 have been performed under constant, uni-axial, compressive load using a custom designed apparatus. The apparatus uses a combination of extensometers and linear variable differential transformers coupled with a data acquisition system, thermal controls, and gravitational loading. The materials being tested consist of a crystalline explosive material mixed with a polymeric binder. The behavior of each material is related to the type of explosive and to the percentage and type of binder. For any given plastic-bonded explosive, the creep behavior is also dependent on the stress level and test temperature. Experiments were conducted using a 3 x 3 stress-temperature matrix with a temperature range of 24 C to 70 C and with stresses ranging from 250-psi to 780-psi. Analysis of the data has shown that logarithmic curve fits provide an accurate means of quantification and facilitate a long-term predictive capability. This paper will discuss the design of the apparatus, experimental results, and analyses.

Gagliardi, F J; Cunningham, B J

2008-03-13

50

Marked and Unmarked Choices of Code Switching in Bilingual Poetry.  

ERIC Educational Resources Information Center

Presents a model of the speaker's sociopsychological motivations when he engages in code-switching (CS). The use of CS can be interpreted as a marked or an unmarked choice of discourse mode. (38 references) (Author/CK)

Mendieta-Lombardo, Eva; Cintron, Zaida A.

1995-01-01

51

Aspects of the Tribology of the Plastic Bonded Explosive LX-04  

SciTech Connect

The coefficient of friction, {mu}, of the plastic bonded explosive (PBX) LX-04 was measured on stainless steel, aluminum, Teflon and the explosive itself as a function of temperature between ambient and 135 C at a rotational speed of 0.0025 rad/sec{sup -1}. An optical profilometer was used to analyze the mean surface roughness, R{sub a}, of the various materials. LX-04 is a composite of the explosive 1,3,5,7-tetranitroazacyclooctane (HMX) and Viton A in an 85/15 weight ratio. The average roughness of the pressed explosive surface was R{sub a} = 0.55 {micro}m. The coefficient of friction for LX-04 on stainless steel of R{sub a} = 0.40 {micro}m decreased from 0.38 at ambient to 0.18 at 95 C. Above this temperature {mu} was nearly constant to about 125 C, where the coefficient began to increase again. The opposite behavior was observed with aluminum with R{sub a} = 0.31 {micro}m. The coefficient of friction increased from about 0.3 at ambient to 0.46 at 125 C. At this temperature or above, {mu} tended to increase during the measurement, indicating that the sample may have been sticking to the counter surface. The coefficient of friction against Teflon of R{sub a} = 0.054 {micro}m was nearly constant from ambient to 65 C at 0.43 {+-} 0.02, then decreased to 0.17 at 100 C and remained there up to 135 C. Against LX-04 itself at temperatures between 35 and 95 C the coefficient of friction averaged 0.64, but tended to increase during the measurement, probably due to adhesion of the Viton to itself. Above 95 C the coefficient dropped off and became nearly constant again at 0.16 from 115 up to 135 C. Some preliminary measurements on stainless steel with the mock explosive RM-04-BR, a composite of cyanuric acid and Viton A in the same weight ratio as the actual explosive, were made to evaluate the set up procedures and safety of the operation with live explosive. Both pressed, R{sub a} = 0.37 {micro}m, and machined, R{sub a} = 1.7 {micro}m, surfaces were evaluated for the mock. Results compared reasonably well with the explosive itself on steel, indicating that the binder plays a major role in determining the coefficient of friction for these types of composites.

Hoffman, D M; Chandler, J B

2004-07-08

52

On the Nature of Variations in Density and Composition within TATB-based Plastic Bonded Explosives  

SciTech Connect

Initiation of insensitive high explosives is affected by porosity in the 100 nm to micron size range. It is also recognized that as-pressed plastic bonded explosives (PBX) are heterogeneous in composition and density at much coarser length scale (10 microns-100 microns). However, variations in density and composition of these explosives have been poorly characterized. Here, we characterize the natural variations in composition and density of TATB-based PBX LX-17 with synchrotron radiation tomography and ultra small angle x-ray scattering. Large scale variations in composition occur as a result of binder enrichment at the prill particle boundaries. The pore fraction is twice as high in the prill particle as in the boundary. The pore distribution is bimodal, with small pores of 50-100 nm in radius and a broader distribution of pores in the 0.5-1.5 micron size range. The higher pore density within the prill particle is attributed to contact asperities between the crystallites that might inhibit complete consolidation and binder infiltration.

Kinney, J H; Willey, T M; Overturf, G

2006-06-27

53

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

SciTech Connect

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

Hoffman, D M; Chandler, J B

2004-07-08

54

Coupled phase transformation, chemical decomposition, and deformation in plastic-bonded explosive: Simulations  

NASA Astrophysics Data System (ADS)

Numerical simulations of the heating with constant rate of a PBX (plastic-bonded explosive) 9501 formulation consisting of the energetic crystal HMX embedded in a polymeric binder inside of a rigid cylinder is performed. The continuum thermo-mechanochemical model of the behavior of a PBX 9501 developed in the preceding paper [V. I. Levitas, B. F. Henson, L. B. Smilowitz, D. K. Zerkle, and B. W. Asay, J. Appl. Phys. 102, 113502 (2007)] is applied. The model describes the ? ?? phase transformations in crystalline HMX, chemical decomposition of the HMX and binder leading to gas formation, gas leaking from the cylinder, elastic, thermal, and transformational straining, as well as straining due to mass loss. We study the kinetics of the ? ?? phase transformations and pressure buildup, as well as how they are affected by the heating rate, initial porosity and prestrain, HMX and binder decomposition, and gas leaking rule.

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

2007-12-01

55

Meso-scale Origins of the Low Pressure Equation of State and High Rate Mechanical Properties of Plastic Bonded Explosives  

Microsoft Academic Search

Most modern high explosives are formulated from a selection of energetic crystalline materials and plastics to create a material that accommodates the performance and sensitivity characteristic of the desired application.1 These materials are exposed to a variety of thermal-mechanical loads during their service life. Recent interest has focused research on safety and survivability under conditions that produce long duration low

Joseph C. Foster Jr.; Joseph G. Glenn; Mike Gunger

1999-01-01

56

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

SciTech Connect

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

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

2009-01-01

57

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

SciTech Connect

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

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

1998-12-31

58

Portable standoff Raman system for fast detection of homemade explosives through glass, plastic, and water  

NASA Astrophysics Data System (ADS)

The University of Hawaii has been developing portable remote Raman systems capable of detecting chemicals in daylight from a safe standoff distance. We present data on standoff detection of chemicals used in the synthesis of homemade explosives (HME) using a portable standoff Raman system utilizing an 8-inch telescope. Data show that good-quality Raman spectra of various hazardous chemicals such as ammonium nitrate, potassium nitrate, potassium perchlorate, sulfur, nitrobenzene, benzene, acetone, various organic and inorganic chemicals etc. could be easily obtained from remote distances, tested up to 120 meters, with a single-pulse laser excitation and with detection time less than 1 ?s. The system uses a frequency-doubled Nd:YAG pulsed laser source (532 nm, 100 mJ/pulse, 15 Hz, pulse width 10 ns) capable of firing a single or double pulse. The double-pulse configuration also allows the system to perform standoff LIBS (Laser-Induced Breakdown Spectroscopy) at 50 m range. In the standoff Raman detection, the doublepulse sequence simply doubles the signal to noise ratio. Significant improvement in the quality of Raman spectra is observed when the standoff detection is made with 1s integration time. The system uses a 50-micron slit and has spectral resolution of 8 cm-1. The HME chemicals could be easily detected through clear and brown glass bottles, PP and HDPE plastic bottles, and also through fluorescent plastic water bottles. Standoff Raman detection of HME chemical from a 10 m distance through non-visible concealed bottles in plastic bubble wrap packaging is demonstrated with 1 s integration time. Possible applications of the standoff Raman system for homeland security and environmental monitoring are discussed.

Misra, Anupam K.; Sharma, Shiv K.; Acosta, Tayro E.; Porter, John N.; Lucey, Paul G.; Bates, David E.

2012-06-01

59

Performance evaluation of booster materials in the plastic bonded explosive PBX 9502 in a hemispherical wave breakout test  

SciTech Connect

An explosive booster is normally required to initiate detonation in an insensitive high explosive (lHE). Booster materials must be ignitable by a conventional detonator and deliver sufficient energy and favorable pulse shape to initiate the IHE charge. The explosive booster should be as insensitive as reasonably possible to maintain the overall safety margin of the explosive assembly. A hemispherical wave breakout test termed the on ionskin test is one of the methods of testing the performance of booster materials in an initiation train assembly. There are several variations of this basic test which are known by other names. In this test, the wave breakout time-position history at the surface of a hemispherical IHE acceptor charge is recorded, and the relative uniformity of breakout allows qualitative comparison between booster candidates and quantitative comparison of several metrics. The results of a series of onionskin experiments evaluating the performance of some new booster formulations in the triaminotrinitrobenzene (TA TB) -based plastic bonded explosive PBX 9502 will be presented. The boosters were tested in an onionskin arrangement in which the booster pellet was cylindrical, and the tests were performed at a temperature of-55{sup o}C to emphasize variations in spreading performance. The modification from the traditional hemispherical geometry facilitated efficient explosive fabrication and charge assembly, but the results indicate that this geometry was not ideal for several reasons. Despite the complications arising from geometry, promising performance was observed from booster formulations including 3,3' -diamino-4,4'azoxyfurazan.

Hooks, Daniel E [Los Alamos National Laboratory; Morris, John S [Los Alamos National Laboratory; Hill, Larry G [Los Alamos National Laboratory; Francois, Elizabeth [Los Alamos National Laboratory

2008-01-01

60

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

PubMed

Molecular dynamics simulations have been performed to investigate well-known energetic material cyclotrimethylene trinitramine (RDX) crystal and RDX-based plastic-bonded explosives (PBXs) with four typical fluorine-polymers, polyvinylidenedifluoride (PVDF), polychlorotri-fluoroethylene (PCTFE), fluorine rubber (F(2311)), and fluorine resin (F(2314)). The elastic coefficients, mechanical properties, binding energies, and detonation performances are obtained for the RDX crystal and RDX-based PBXs. The results indicate that the mechanical properties of RDX can be effectively improved by blending with a small amount of fluorine polymers and the overall effect of fluorine polymers on the mechanical properties of the PBXs along three crystalline surfaces is (001)>(010) approximately (100) and PVDF is regarded to best improve the mechanical properties of the PBXs on three surfaces. The order of the improvement in the ductibility made by the fluorine polymers on different surfaces is (001) approximately (010)>(100). The average binding energies between different RDX crystalline surfaces and different polymer binders are obtained, and the sequence of the binding energies of the PBXs with the four fluorine polymers on the three different surfaces is varied. Among the polymer binders, PVDF is considered as best one for RDX-based PBXs. The detonation performances of the PBXs decrease in comparison with the pure crystal but are superior to those of TNT. PMID:18938030

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

2009-05-30

61

Clean, agile alternative binders, additives and plasticizers for propellant and explosive formulations  

Microsoft Academic Search

As part of the Strategic Environmental Research and Development Program (SERDP) a clean, agile manufacturing of explosives, propellants and pyrotechniques (CANPEP) effort set about to identify new approaches to materials and processes for producing propellants, explosives and pyrotechniques (PEP). The RDX based explosive PBXN-109 and gun propellant M-43 were identified as candidates for which waste minimization and recycling modifications might

D. M. Hoffman; T. W. Hawkins; G. A. Lindsay

1994-01-01

62

Thermal Decomposition of Plastic Bonded Explosives by Molecular Dynamic Simulations with the ReaxFF Force Field  

NASA Astrophysics Data System (ADS)

Plastic bonded explosives (PBX) are a type of composite energetic materials in which a high explosive is dispersed in a polymer matrix. The main purpose of making such high explosive polymer bound is to reduce their sensitivity to shock, friction, impact, etc. Thermal decomposition is an essential process to characterize an energetic material, because it is one of main causes of initiation of the explosives. In this work, we used MD simulations with the reactive force field (ReaxFF) to study the thermal decomposition of RDX crystal boned with polyurethane chains (Estane) and with nitrocellulose chains. The simulation results showed that RDX's thermal decomposition processing varies when a polymer binder was bonded to the crystal. With addition of polymer binders, RDX's sensitivity is reduced. In all cases studied, the products such as N2, H2O, CO, CO2, OH, etc. can be identified. However, the contributions to these individual species are different: nitrocellulose has much more contributions to N2, CO2, and CO; but Estane has a little contributions to H2O and almost no contributions to N2, CO and CO2. In addition, we found that the decomposition of RDX with Estane along the Y-direction is slower than that along the X-direction.

Zhang, Luzheng

2005-03-01

63

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

NASA Astrophysics Data System (ADS)

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

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

2007-12-01

64

10 CFR 1045.45 - Review of unmarked documents with potential restricted data or formerly restricted data.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Review of unmarked documents with potential restricted data or formerly restricted data. 1045.45...Restricted Data § 1045.45 Review of unmarked documents with potential restricted data or formerly restricted data....

2010-01-01

65

27 CFR 555.183 - Importation of plastic explosives on or after April 24, 1997.  

Code of Federal Regulations, 2010 CFR

27 Alcohol, Tobacco Products and Firearms 3...Section 555.183 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES...amount” to be used for research, training, or testing...

2010-04-01

66

27 CFR 555.183 - Importation of plastic explosives on or after April 24, 1997.  

Code of Federal Regulations, 2011 CFR

27 Alcohol, Tobacco Products and Firearms 3...Section 555.183 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES...amount” to be used for research, training, or testing...

2011-04-01

67

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

SciTech Connect

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

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

2009-01-01

68

Cost-effective synthesis of 5,7-diamino-4,6-dinitrobenzofuroxan (CL-14) and its evaluation in plastic bonded explosives.  

PubMed

5,7-Diamino-4,6-dinitrobenzofuroxan (CL-14) has been synthesized by a cost-effective method. CL-14 was characterized by spectral data (IR, NMR and mass) and elemental analysis. The compound was evaluated in plastic bonded explosives (PBX) using polyurethane (PU) as binder. The thermal, mechanical and explosive properties of PBX composition from preliminary tests are also reported. Good thermal stability as well as good insensitiveness are indicated. PMID:12972233

Mehilal; Sikder, A K; Sinha, R K; Gandhe, B R

2003-08-29

69

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

Microsoft Academic Search

We have implemented the burn model in LS-DYNA. At present, the damage (porosity and specific surface area) is specified as initial conditions. However, history variables that are used by the strength model are reserved as placeholders for the next major revision, which will be a completely interactive model. We have implemented an improved strength model for explosives based on a

Reaugh

2009-01-01

70

Meso-scale origins of the low-pressure equation of state and high rate mechanical properties of plastic bonded explosives  

Microsoft Academic Search

Most modern high explosives are formulated from a selection of energetic crystalline materials and plastics to create a material that accommodates the performance and sensitivity characteristic of the desired application. These materials are exposed to a variety of thermal-mechanical loads during their service life. Recent interest has focused research on safety and survivability under conditions that produce long duration, low

Joseph C. Foster; Joseph G. Glenn; Mike Gunger

2000-01-01

71

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

SciTech Connect

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

Reaugh, J E

2009-05-07

72

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

Microsoft Academic Search

The coefficient of friction, ?, of PBX 9404 was measured on stainless steel, aluminum, polytetrafluoroethylene (PTFE), and the explosive itself between ambient and 135°C at a rotational speed of 0.0025 rad\\/s. The mean surface roughness, Ra, of the various materials was analyzed by an optical profilometer. For PBX 9404 on stainless steel, ? increased from 0.22 at 25?°C to 0.34 at

D. MARK HOFFMAN; JEFFREY B. CHANDLER

2004-01-01

73

Modeling structured population dynamics using data from unmarked individuals.  

PubMed

The study of population dynamics requires unbiased, precise estimates of abundance and vital rates that account for the demographic structure inherent in all wildlife and plant populations. Traditionally, these estimates have only been available through approaches that rely on intensive mark-recapture data. We extended recently developed N-mixture models to demonstrate how demographic parameters and abundance can be estimated for structured populations using only stage-structured count data. Our modeling framework can be used to make reliable inferences on abundance as well as recruitment, immigration, stage-specific survival, and detection rates during sampling. We present a range of simulations to illustrate the data requirements, including the number of years and locations necessary for accurate and precise parameter estimates. We apply our modeling framework to a population of northern dusky salamanders (Desmognathus fuscus) in the mid-Atlantic region (USA) and find that the population is unexpectedly declining. Our approach represents a valuable advance in the estimation of population dynamics using multistate data from unmarked individuals and should additionally be useful in the development of integrated models that combine data from intensive (e.g., mark-recapture) and extensive (e.g., counts) data sources. PMID:24649642

Zipkin, Elise F; Thorson, James T; See, Kevin; Lynch, Heather J; Grant, Evan H Campbell; Kanno, Yoichiro; Chandler, Richard B; Letcher, Benjamin H; Royle, J Andrew

2014-01-01

74

Explosive simulants for testing explosive detection systems  

DOEpatents

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.

Kury, John W. (Danville, CA); Anderson, Brian L. (Lodi, CA)

1999-09-28

75

Extrusion cast explosive  

DOEpatents

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

Scribner, Kenneth J. (Livermore, CA)

1985-01-01

76

On the low pressure shock initiation of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine based plastic bonded explosives  

NASA Astrophysics Data System (ADS)

In large explosive and propellant charges, relatively low shock pressures on the order of 1-2 GPa impacting large volumes and lasting tens of microseconds can cause shock initiation of detonation. The pressure buildup process requires several centimeters of shock propagation before shock to detonation transition occurs. In this paper, experimentally measured run distances to detonation for lower input shock pressures are shown to be much longer than predicted by extrapolation of high shock pressure data. Run distance to detonation and embedded manganin gauge pressure histories are measured using large diameter charges of six octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) based plastic bonded explosives (PBX's): PBX 9404; LX-04; LX-07; LX-10; PBX 9501; and EDC37. The embedded gauge records show that the lower shock pressures create fewer and less energetic "hot spot" reaction sites, which consume the surrounding explosive particles at reduced reaction rates and cause longer distances to detonation. The experimental data is analyzed using the ignition and growth reactive flow model of shock initiation in solid explosives. Using minimum values of the degrees of compression required to ignite hot spot reactions, the previously determined high shock pressure ignition and growth model parameters for the six explosives accurately simulate the much longer run distances to detonation and much slower growths of pressure behind the shock fronts measured during the shock initiation of HMX PBX's at several low shock pressures.

Vandersall, Kevin S.; Tarver, Craig M.; Garcia, Frank; Chidester, Steven K.

2010-05-01

77

A new proof of the Pythagorean using a compass and unmarked straight edge  

Microsoft Academic Search

In this note, a new proof of the Pythagorean Theorem will be presented using only a compass and an unmarked straight edge. As a background, interesting dissection proofs of the Hindu mathematician Bhaskara and the Arabic scholar Tabit ibn-Qorra are highlighted.

Medhat H. Rahim

2003-01-01

78

Extrusion cast explosive  

DOEpatents

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

Scribner, K.J.

1985-01-29

79

Extrusion cast explosive  

DOEpatents

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

Scribner, K.J.

1985-11-26

80

Method for preparation of fine TATB (2-5 microm) and its evaluation in plastic bonded explosive (PBX) formulations.  

PubMed

There is a need of fine 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) (2-5 microm) for various high explosive formulations to achieve desired mechanical strength, ease in processing and finally, provide better performance of end product. The reprecipitation method for TATB has been developed using concentrated sulfuric acid as a solvent. The reprecipitation parameters of TATB were optimized to achieve required fine TATB of particle size approximately 2-5 microm. The characteristic properties of fine TATB thus obtained have been confirmed by FTIR, DSC and TG-FTIR. The spectroscopic and thermal data obtained for fine TATB were compared with standard coarse TATB and found chemically unchanged during particle size reduction. In the present study, the preparation of fine TATB was also attempted using ultrasonication method. The fine (2-5 microm) TATB has been introduced to study in the bimodal high explosive formulations. High explosive formulations based on coarse (55 microm) and fine TATB ( approximately 2-5 microm) with 10% polyurethane were studied. It was observed that properties like bulk density (1.70 g/cm(3)), mechanical strength/compressed strength (115.9 mg/cm(2)), %elongation (6.36) were improved for fine TATB in comparison with coarse TATB ( approximately 55 microm) alone in high explosive formulations. PMID:16844291

Talawar, M B; Agarwal, A P; Anniyappan, M; Gore, G M; Asthana, S N; Venugopalan, S

2006-10-11

81

Molecular simulation of the influence of interface faceting on the shock sensitivity of a model plastic bonded explosive.  

PubMed

Molecular dynamics simulations are used to model the shock loading of an interface with various degrees of nanometer scale faceting between an inert binder and an energetic crystal. The facets create regions of local compression that induce exothermic reaction that leads to local hotspots and an increased shock sensitivity to detonation. Two mechanisms for compression and hotspot formation are identified that depend on the shock impedance mismatch between the binder and energetic crystal, namely shock focusing and local compression of the facets. These results provide a possible explanation for why spherical RDX crystals in cast polymer-bonded explosives appear less shock sensitive than RDX with more faceted morphologies. PMID:18973371

Shi, Yunfeng; Brenner, Donald W

2008-11-27

82

Abundance, stock origin, and length of marked and unmarked juvenile Chinook salmon in the surface waters of greater Puget Sound  

USGS Publications Warehouse

This study focuses on the use by juvenile Chinook salmon Oncorhynchus tshawytscha of the rarely studied neritic environment (surface waters overlaying the sublittoral zone) in greater Puget Sound. Juvenile Chinook salmon inhabit the sound from their late estuarine residence and early marine transition to their first year at sea. We measured the density, origin, and size of marked (known hatchery) and unmarked (majority naturally spawned) juveniles by means of monthly surface trawls at six river mouth estuaries in Puget Sound and the areas in between. Juvenile Chinook salmon were present in all months sampled (April-November). Unmarked fish in the northern portion of the study area showed broader seasonal distributions of density than did either marked fish in all areas or unmarked fish in the central and southern portions of the sound. Despite these temporal differences, the densities of marked fish appeared to drive most of the total density estimates across space and time. Genetic analysis and coded wire tag data provided us with documented individuals from at least 16 source populations and indicated that movement patterns and apparent residence time were, in part, a function of natal location and time passed since the release of these fish from hatcheries. Unmarked fish tended to be smaller than marked fish and had broader length frequency distributions. The lengths of unmarked fish were negatively related to the density of both marked and unmarked Chinook salmon, but those of marked fish were not. These results indicate more extensive use of estuarine environments by wild than by hatchery juvenile Chinook salmon as well as differential use (e.g., rearing and migration) of various geographic regions of greater Puget Sound by juvenile Chinook salmon in general. In addition, the results for hatchery-generated timing, density, and length differences have implications for the biological interactions between hatchery and wild fish throughout Puget Sound. ?? American Fisheries Society 2011.

Rice, C.A.; Greene, C.M.; Moran, P.; Teel, D.J.; Kuligowski, D.R.; Reisenbichler, R.R.; Beamer, E.M.; Karr, J.R.; Fresh, K.L.

2011-01-01

83

The role of the posterior superior temporal sulcus in the processing of unmarked transitivity.  

PubMed

Is it living or not? The ability to differentiate between animate and inanimate entities is of considerable value in everyday life, since it allows for the dissociation of individuals that may willfully cause an action from objects that cannot. The present fMRI study aimed to shed light on the neural correlates of animacy at a relational-interpretive level, i.e. on the role of animacy in the establishment of relations between entities that are more or less likely to cause an event and differ in their potential to act volitionally. To this end, we investigated the processing of visually presented transitive German sentences (nominative-accusative structures) in which the factors animacy and argument order were manipulated. The relations between the arguments differed in that the animate subject either acted on an inanimate object (a very natural construction in terms of transitivity) or on an animate object (resulting in a sentence deviating from an unmarked transitive structure). Participants performed an acceptability judgment task. Violations of unmarked transitivity yielded a significant activation increase within the posterior left superior temporal sulcus (pSTS), thus suggesting a specific role of this cortical region in the relational use of animacy information. This result indicates that the influence of animacy as a relational feature differs from the impact of this parameter on the word level and is in line with other neuroimaging studies showing an engagement of the pSTS when a matching between syntax and semantics is required. A comparison between object- and subject-initial conditions further revealed a robust effect of argument order in the pars opercularis of the left inferior frontal gyrus (a subregion of Broca's area), thereby replicating previous findings demonstrating a sensitivity of this region to fine-grained language-specific linearization rules. PMID:17222565

Grewe, Tanja; Bornkessel-Schlesewsky, Ina; Zysset, Stefan; Wiese, Richard; von Cramon, D Yves; Schlesewsky, Matthias

2007-03-01

84

Evaluation of novel Brucella melitensis unmarked deletion mutants for safety and efficacy in the goat model of brucellosis  

Microsoft Academic Search

Pregnant goats were employed to assess unmarked deletion mutant vaccine candidates BM?asp24, BM?cydBA, and BM?virB2, as the target host species naturally infected with Brucella melitensis. Goats were assessed for the degree of pathology associated with the vaccine strains as well as the protective immunity afforded by each strain against abortion and infection after challenge with wild-type Brucella melitensis 16M. Both

Melissa M. Kahl-McDonagh; Philip H. Elzer; Sue D. Hagius; Joel V. Walker; Quinesha L. Perry; Christopher M. Seabury; Andreas B. den Hartigh; Renee M. Tsolis; L. Garry Adams; Donald S. Davis; Thomas A. Ficht

2006-01-01

85

Efficient and simple generation of unmarked gene deletions in Mycobacterium smegmatis.  

PubMed

Genetic research in molecular laboratories relies heavily on directed mutagenesis and gene deletion techniques. In mycobacteria, however, genetic analysis is often hindered by difficulties in the preparation of deletion mutants. Indeed, in comparison to the allelic exchange systems available for the study of other common model organisms, such as Saccharomyces cerevisiae and Escherichia coli, mycobacterial gene disruption systems suffer from low mutant isolation success rates, mostly due to inefficient homologous recombination and a high degree of non-specific recombination. Here, we present a gene deletion system that combines efficient homologous recombination with advanced screening of mutants. This novel methodology allows for gene disruption in three consecutive steps. The first step relies on the use of phage Che9c recombineering proteins for directed insertion into the chromosome of a linear DNA fragment that encodes GFP and confers hygromycin resistance. In the second step, GFP positive and hygromycin resistant colonies are selected, and in the last step, the gfp-hyg cassette is excised from the chromosome, thus resulting in the formation of an unmarked deletion. We provide a detailed gene deletion methodology and demonstrate the use of this genetic system by deleting the prcSBA operon of Mycobacterium smegmatis. PMID:24100088

Shenkerman, Yael; Elharar, Yifat; Vishkautzan, Marina; Gur, Eyal

2014-01-01

86

Dynamic mechanical and molecular weight measurements on polymer bonded explosives from thermally accelerated aging tests. III. Kraton block copolymer binder and plasticizers  

Microsoft Academic Search

The dynamic mechanical properties and molecular weight distribution of two experimental polymer bonded explosives, X-0287 and X-0298, maintained at 23, 60, and 74°C for 3 years were examined. X-0287 is 97% 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane explosive, 1.8% Kraton G-1650, and 1.2% B² was 170. X-0298 is 97.4% explosive, 1.4% Kraton G-1650, and 1.2% Cenco Hi-vac oil. The relaxation associated with the Kraton rubber

L. E. Caley; D. M. Hoffman

1981-01-01

87

Explosives detection with quadrupole resonance analysis  

Microsoft Academic Search

The increase in international terrorist activity over the past decade has necessitated the exploration of new technologies for the detection of plastic explosives. Quadrupole resonance analysis (QRA) has proven effective as a technique for detecting the presence of plastic, sheet, and military explosive compounds in small quantities, and can also be used to identify narcotics such as heroin and cocaine

Timothy J. Rayner; Benjamin D. Thorson; Simon Beevor; Rebecca West; Ronald A. Krauss

1997-01-01

88

Explosives tester  

DOEpatents

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

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

2011-01-11

89

Appearances of internal micro bubbling, multiple micro explosions, multiple micro jets and micro diffusion flames around an abruptly heated micro plastic-resin particle  

Microsoft Academic Search

Heating, gasifying and burning processes of a micro plastic-resin particle, which has a diameter of about 200?m and is suddenly exposed to a hot oxidizing atmosphere, are observed and optically processed by combining a micro schlieren system with a high-speed CCD video camera. The following three devised approaches are introduced: the use of an oxidizing combustion gas downstream of a

Yojiro Ishino; Ryuji Yamakita; Norio Ohiwa

2007-01-01

90

Evaluation of novel Brucella melitensis unmarked deletion mutants for safety and efficacy in the goat model of brucellosis.  

PubMed

Pregnant goats were employed to assess unmarked deletion mutant vaccine candidates BMDeltaasp24, BMDeltacydBA, and BMDeltavirB2, as the target host species naturally infected with Brucella melitensis. Goats were assessed for the degree of pathology associated with the vaccine strains as well as the protective immunity afforded by each strain against abortion and infection after challenge with wild-type Brucella melitensis 16M. Both BMDeltaasp24 and BMDeltavirB2 were considered safe vaccine candidates in the pregnant goat model because they did not cause abortion or colonize fetal tissues. BMDeltaasp24 was isolated from the maternal tissues only, indicating a slower rate of clearance of the vaccine strain than for BMDeltavirB2, which was not isolated from any maternal or fetal tissues. Both strains were protective against abortion and against infection in the majority of pregnant goats, although BMDeltaasp24 was more efficacious than BMDeltavirB2 against challenge infection. PMID:16697090

Kahl-McDonagh, Melissa M; Elzer, Philip H; Hagius, Sue D; Walker, Joel V; Perry, Quinesha L; Seabury, Christopher M; den Hartigh, Andreas B; Tsolis, Renee M; Adams, L Garry; Davis, Donald S; Ficht, Thomas A

2006-06-12

91

Explosive nucleosynthesis  

E-print Network

Many radioactive nuclei relevant for gamma-ray astrophysics are synthesized during explosive events, such as classical novae and supernovae. A review of recent results of explosive nucleosynthesis in these scenarios is presented, with a special emphasis on the ensuing gamma-ray emission from individual nova and supernova explosions. The influence of the dynamic properties of the ejecta on the gamma-ray emission features, as well as the still remaining uncertainties in nova and supernova models is also reviewed.

M. Hernanz

2001-03-26

92

Spatial and trophic overlap of marked and unmarked Columbia River Basin spring Chinook salmon during early marine residence with implications for competition between hatchery and naturally produced fish  

Microsoft Academic Search

Ecological interactions between natural and hatchery juvenile salmon during their early marine residence, a time of high mortality,\\u000a have received little attention. These interactions may negatively influence survival and hamper the ability of natural populations\\u000a to recover. We examined the spatial distributions and size differences of both marked (hatchery) and unmarked (a high proportion\\u000a of which are natural) juvenile Chinook

Elizabeth A. Daly; Richard D. Brodeur; Joseph P. Fisher; Laurie A. Weitkamp; David J. Teel; Brian R. Beckman

93

An Analytic Tool to Investigate the Effect of Binder on the Sensitivity of HMX-Based Plastic Bonded Explosives in the Skid Test  

SciTech Connect

This project will develop an analytical tool to calculate performance of HMX based PBXs in the skid test. The skid-test is used as a means to measure sensitivity for large charges in handling situations. Each series of skid tests requires dozens of drops of large billets. It is proposed that the reaction (or lack of one) of PBXs in the skid test is governed by the mechanical properties of the binder. If true, one might be able to develop an analytical tool to estimate skid test behavior for new PBX formulations. Others over the past 50 years have tried to develop similar models. This project will research and summarize the works of others and couple the work of 3 into an analytical tool that can be run on a PC to calculate drop height of HMX based PBXs. Detonation due to dropping a billet is argued to be a dynamic thermal event. To avoid detonation, the heat created due to friction at impact, must be conducted into the charge or the target faster than the chemical kinetics can create additional energy. The methodology will involve numerically solving the Frank-Kamenetskii equation in one dimension. The analytical problem needs to be bounded in terms of how much heat is introduced to the billet and for how long. Assuming an inelastic collision with no rebound, the billet will be in contact with the target for a short duration determined by the equations of motion. For the purposes of the calculations, it will be assumed that if a detonation is to occur, it will transpire within that time. The surface temperature will be raised according to the friction created using the equations of motion of dropping the billet on a rigid surface. The study will connect the works of Charles Anderson, Alan Randolph, Larry Hatler, Alfonse Popolato, and Charles Mader into a single PC based analytic tool. Anderson's equations of motion will be used to calculate the temperature rise upon impact, the time this temperature is maintained (contact time) will be obtained from the work of Hatler et. al., and the reactive temperature rise will be obtained from Mader's work. Finally, the assessment of when a detonation occurs will be derived from Bowden and Yoffe's thermal explosion theory (hot spot).

D.W. Hayden

2005-02-01

94

An Orientation to Explosive Safety.  

ERIC Educational Resources Information Center

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

Harris, Betty W.

1987-01-01

95

"Explosive" Physics.  

ERIC Educational Resources Information Center

Describes a physics demonstration in which two-liter plastic bottles can be used to show how force relates to pressure and area. Identical drinking straws are launched out of similar plastic bottles with different-sized openings. This demonstration proves qualitatively that pressure is inversely proportional to the area exposed to an object when a…

Kienzynski, Mark J.

1998-01-01

96

Nanoengineered explosives  

DOEpatents

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

Makowiecki, Daniel M. (Livermore, CA)

1996-01-01

97

Nanoengineered explosives  

DOEpatents

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

Makowiecki, D.M.

1996-04-09

98

Plastic Surgery  

MedlinePLUS

... forehead lightened with a laser? What Is Plastic Surgery? Just because the name includes the word "plastic" ... such treatments. Continue Why Do Teens Get Plastic Surgery? Most teens don't, of course. But some ...

99

Soda Explosion  

NSDL National Science Digital Library

This hands-on activity lets participant explore chemical reactions as they create a soda explosion with lots of bubbles. The bubbles in soda are made of carbon dioxide gas. Using lifesaver mint candy, create a fun, foaming mess. Experimenting in an outside space is suggested.

Connecticut, Science C.

1999-01-01

100

Explosive complexes  

DOEpatents

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

Huynh, My Hang V. (Los Alamos, NM)

2011-08-16

101

Population Explosion  

NSDL National Science Digital Library

A series of experiments explore the effects of increased population growth on a population of Fast Plants. Through these inquiries, students will better understand the many substantial and pertinent issues surrounding human population explosion on Earth.These experiments can be adjusted toward middle, high school or post-secondary levels.

The Wisconsin Fast Plants Program

102

Explosive complexes  

DOEpatents

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

Huynh, My Hang V. (Los Alamos, NM)

2009-09-22

103

Demonstration Explosion  

NASA Astrophysics Data System (ADS)

Last week I did a demonstration that produced a serious explosion. After putting methanol in a big glass carboy and rotating the carboy to build up some methanol vapor, I lit the mouth of the carboy. What normally happens is a "jet engine" effect out of the mouth of the carboy. In my case, the carboy exploded. Two polycarbonate blast shields were shattered and glass was blown as far as 15 feet away. I was not seriously cut and bruised, but had I not been using the two blast shields, I would have been severely injured. At this time, I am not sure what caused the explosion. I have done this demonstration around one hundred times with no problem using the exact same amount of methanol and technique. I think it is important to get the word out that this demonstration may be more dangerous than previously thought. I would also welcome any hypotheses concerning what caused the carboy to explode.

Lee, Charles "Skip"

1998-05-01

104

Explosive Joining  

NASA Technical Reports Server (NTRS)

Laurence J. Bement of Langley Research Center invented a technique to permit metal joining operations under hazardous or inaccessible conditions. The process, which provides a joint with double the strength of the parent metal, involves the use of very small quantities of ribbon explosive to create hermetically sealed joints. When the metal plates are slammed together by the explosion's force, joining is accomplished. The collision causes a skin deep melt and ejection of oxide films on the surfaces, allowing a linkup of electrons that produce superstrong, uniform joints. The technique can be used to join metals that otherwise would not join and offers advantages over mechanical fasteners and adhesives. With Langley assistance, Demex International Ltd. refined and commercialized the technology. Applications include plugging leaking tubes in feedwater heaters. Demex produces the small plugs, associated sleeves and detonators. The technology allows faster plugging, reduces downtime, cuts plugging costs and increases reliability.

1989-01-01

105

Unmarked gene deletion mutagenesis of kstD, encoding 3-ketosteroid Delta1-dehydrogenase, in Rhodococcus erythropolis SQ1 using sacB as counter-selectable marker.  

PubMed

This paper reports the first method for the construction of unmarked gene deletion mutants in the genus Rhodococcus. Unmarked deletion of the kstD gene, encoding 3-ketosteroid Delta1-dehydrogenase (KSTD1) in Rhodococcus erythropolis SQ1, was achieved using the sacB counter-selection system. Conjugative mobilization of the mutagenic plasmid from Escherichia coli S17-1 to R. erythropolis strain SQ1 was used to avoid its random genomic integration. The kstD gene deletion mutant, designated strain RG1, still possessed about 10% of the KSTD enzyme activity of wild-type and was not affected in its ability to grow on the steroid substrates 4-androstene-3,17-dione (AD) and 9alpha-hydroxy-4-androstene-3,17-dione (9OHAD). Biochemical evidence subsequently was obtained for the presence of a second KSTD enzyme (KSTD2) in R. erythropolis SQ1. UV mutants of strain RG1 unable to grow on AD were isolated. One of these mutants, strain RG1-UV29, had lost all KSTD enzyme activity and was also unable to grow on 9OHAD. It stoichiometrically converted AD into 9OHAD in concentrations as high as 20 g x l(-1). The two KSTD enzymes apparently both function in AD and 9OHAD catabolism. These isoenzymes have been inactivated in strain RG1 (KSTD1 negative) and strain RG1-UV29 (KSTD1 and KSTD2 negative), respectively. PMID:11750802

van der Geize, R; Hessels, G I; van Gerwen, R; van der Meijden, P; Dijkhuizen, L

2001-12-18

106

Explosion risks from nanomaterials  

NASA Astrophysics Data System (ADS)

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

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

2009-05-01

107

Analysis of Explosives  

Microsoft Academic Search

The analysis of explosives is of major importance in several analytical fields:1. Forensic identification of explosives is a major problem in the criminalistic investigation of a bombing which involves connecting the type of explosive used with the suspect. The detection and identification of explosive residues in debris material constitutes a highly difficult task. The thermal instability of most explosives, along

Jehuda Yinon; John C. Hoffsommer

1977-01-01

108

Universe Explosions  

E-print Network

A scenario for a quantum big crunch to big bang transition is proposed. We first clarify the similarities between this transition and the final stages of black hole evaporation. The black hole and the universe are thought of as quantum states. The importance of an external observer for understanding the big crunch to big bang transition is emphasized. Then, relying on the similarities between the black hole and the universe, we propose that the transition should be described as an explosion that connects the contracting phase to the expanding one. The explosion occurs when entropy bounds are saturated, or equivalently when the states cease to be semiclassically (meta)stable. We discuss our scenario in three examples: collapsing dust, a brane universe falling into a bulk black hole in anti-de Sitter space, and a contracting universe filled with a negative cosmological constant and a small amount of matter. We briefly discuss the late time observables that may carry some information about the state of the universe before the transition.

Ram Brustein; Maximilian Schmidt-Sommerfeld

2012-09-24

109

Plastic Jellyfish.  

ERIC Educational Resources Information Center

Presents an environmental science activity designed to enhance students' awareness of the hazards of plastic waste for wildlife in aquatic environments. Discusses how students can take steps to reduce the effects of plastic waste. (WRM)

Moseley, Christine

2000-01-01

110

Chaotic Explosions  

E-print Network

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

Altmann, Eduardo G; Tél, Tamás

2015-01-01

111

Chaotic Explosions  

E-print Network

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

Eduardo G. Altmann; Jefferson S. E. Portela; Tamás Tél

2015-01-22

112

Method for digesting a nitro-bearing explosive compound  

DOEpatents

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

Shah, Manish M. (Richland, WA)

2000-01-01

113

Supernova Explosions  

NSDL National Science Digital Library

In this activity, students are reminded that the Universe is made up of elements and that the heavier elements are created inside of a star, as they learned in the "Elements and You" activity. They are introduced to the life cycle of a star and to the way in which a star's mass affects its process of fusion and eventual death. Students discuss the physical concept of equilibrium as a balancing of forces and observe an experiment to demonstrate what happens to a soda can when the interior and exterior forces are not in equilibrium. An analogy is made between this experiment and core collapse in stars, to show the importance of maintaining equilibrium in stars. Finally, students participate in an activity which demonstrates how mass is ejected from a collapsed star in a supernova explosion, thereby dispersing heavier elements throughout the Universe. This activity is part of a series that has been designed specifically for use with Girl Scouts, but the activities can be used in other settings. Most of the materials are inexpensive or easily found. It is recommended that a leader with astronomy knowledge lead the activities, or at least be available to answer questions, whenever possible.

114

Plastic Stretch  

NSDL National Science Digital Library

This learning activity will be helpful for students learning about plastic deformation. Specifically, the exercise looks at plastic deformation in polyethylene, which is found in plastic sheets, bags and other common items. Students will participate in plastic deformation of a polymer, observe "necking" in the material and its effect on strength and relate the behavior of the sample to crystallization. This activity would be suitable at any level, from elementary school to college, with each age group gaining different educational benefits. The lesson should take about 5 to 10 minutes of class time, plus time for discussion. This document will serve as a framework for instructors and may be downloaded in PDF format.

Stoebe, Thomas G.

2012-10-05

115

Plastic bottle  

NSDL National Science Digital Library

Many plastic items, like bags and especially bottles, can be recycled. Recycling the plastic rings that hold soda pop cans together is a major help for the environment. Birds sometimes get stuck in these rings and can't move or eat anymore.

Jake Wasdin (None; )

2006-07-08

116

Plastic Packaging  

NSDL National Science Digital Library

In this data collection and analysis activity students investigate the data in connection with recyclable materials and develop plans to help the environment. Through this activity, students explore recycling plastic containers and graph the frequency of different types of recyclable plastics. The lesson includes student worksheets, extension suggestions, and student questions.

2008-01-01

117

Mechanical Behavior of TNAZ/Hytemp Explosives during High Acceleration  

NASA Astrophysics Data System (ADS)

The mechanical behavior of TNAZ/Hytemp (1,3,3-trinitroazetidine/polyacrylic elastomer) explosives subjected to high acceleration has been studied in an ultracentrifuge. Pressed plastic-bonded TNAZ/Hytemp was studied as a function of the percentage of Hytemp at -10°C and 25°C. The percentage of Hytemp in the samples varied from 1% (weight percent) to 2% (weight percent). Failure occurs when the shear or tensile strength of the explosive is exceeded. The fracture acceleration of pressed plastic-bonded TNAZ/Hytemp decreases with increasing percentage of Hytemp in the explosive at -10°C and 25°C. The fracture acceleration of pressed plastic-bonded 98%/2% (weight percent) TNAZ/Hytemp at 25°C is about 1/3 that at -10°C.

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

2006-07-01

118

Terahertz reflection spectroscopy for the detection of explosives  

NASA Astrophysics Data System (ADS)

Terahertz (THz) technology has been demonstrated as a promising tool for detection of explosives and is being developed for aviation screening and sensing of improvised explosive devices. THz radiation is attractive for many applications due to its ability to penetrate through a wide range of dielectric materials including clothing, paper, cardboard, plastics, and wood. Of course, metals block THz waves as is the case for microwave, IR, and visible light. Our work has involved investigating the reflection spectroscopy of a variety of materials including explosives such as RDX and PETN, plastic explosive taggants such as DMDNB, and other organic materials. We have also investigated the changes of the reflection spectra in varying grades of sucrose. Spectral differences are observed between three grades of crystalline sugar in the region from 0.1 to 1 THz. By exploiting the unique spectral features, the discrimination capabilities of THz reflection spectroscopy points to the broad applicability of identifying a wide variety of materials.

Leahy-Hoppa, Megan R.; Fitch, Michael J.; Osiander, Robert

2008-02-01

119

Inspection tester for explosives  

DOEpatents

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

Haas, Jeffrey S. (San Ramon, CA); Simpson, Randall L. (Livermore, CA); Satcher, Joe H. (Patterson, CA)

2010-10-05

120

Inspection tester for explosives  

DOEpatents

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

Haas, Jeffrey S. (San Ramon, CA); Simpson, Randall L. (Livermore, CA); Satcher, Joe H. (Patterson, CA)

2007-11-13

121

Milk Plastic  

NSDL National Science Digital Library

In this activity, learners transform everyday milk into small plastic figurines and jewelry. Use this activity to introduce learners to monomers and polymers. Note: this activity requires adult supervision.

Workshop, Mission S.

2013-01-01

122

Gas gun for dynamic loading of explosives  

NASA Astrophysics Data System (ADS)

There has long been a need to understand the impact response of explosive materials, and continual improvements result from the design of careful, well-instrumented experiments. This article summarizes details of the design and construction of a laboratory facility capable of launching projectiles at explosive targets at velocities up to 1500 m s-1. There are two types of experiment that are required. In the first, a gun launches a plate of great planarity at an equally flat target. This geometry is known as plate impact and a target loaded in this manner experiences a state of one-dimensional strain. This loading is accomplished by launching plane impactors onto targets aligned to micron tolerances, normal to the impact axis to less than 0.5 mrad of tilt. In the second, it is required to attain the ability to recover impacted explosive targets that have been loaded in one-dimensional strain for subsequent microstructural assessment. The development of this capability will be described in a subsequent publication. The system is capable of containing reactive targets, where design must allow for complete detonation of the target (up to 250 g of explosive). The facility has been completed, is operational, and has been approved for use by the appropriate authorities. An example of a particle velocity sensor in use within a plastic-bonded explosive is given as illustration.

Bourne, N. K.

2004-01-01

123

Method of digesting an explosive nitro compound  

DOEpatents

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

Shah, Manish M. (Richland, WA)

2000-01-01

124

New Mix Explosives for Explosive Welding  

NASA Astrophysics Data System (ADS)

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 ?m. 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 = 2mm. 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.

Andreevskikh, Leonid

2011-06-01

125

Effects of radiation on DMSO solutions with polymeric binders and HMX high explosive  

SciTech Connect

A newly developed dismantlement process uses dimethyl sulfoxide (DMSO) solvent to remove plastic bonded HMX explosives (PBX-9404 and LX-10) from bonded nuclear assemblies. It is remotely possible in this process that DMSO solutions of the explosives will come into prolonged contact with plutonium. This paper addresses the anticipated chemistry and consequences of this contact.

Colmenares, C.A.; LeMay, J.D.

1994-08-01

126

The development of an inert simulant for HNS/teflon explosive  

NASA Technical Reports Server (NTRS)

The report describes the development and evaluation of an inert simulant for the thermally stable, heat-resistant plastic-bonded explosive HNS/Teflon. The simulant is made by dry blending vinylidene fluoride, melamine and Teflon which when compared has a pressed density and thermal properties corresponding closely to the explosive. In addition, the machinability and handling characteristics of the simulant are similar to the explosive.

Elban, W. L.

1972-01-01

127

Explosives tester with heater  

DOEpatents

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

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

2010-08-10

128

Plastics Technician.  

ERIC Educational Resources Information Center

This document contains 16 units to consider for use in a tech prep competency profile for the occupation of plastics technician. All the units listed will not necessarily apply to every situation or tech prep consortium, nor will all the competencies within each unit be appropriate. Several units appear within each specific occupation and would…

Ohio State Univ., Columbus. Center on Education and Training for Employment.

129

Modeling of buried explosions  

SciTech Connect

Los Alamos National Laboratory has been and continues developing techniques for modeling buried explosions using a large geotechnical centrifuge. When fully developed, the techniques should permit the accurate modeling of large explosions in complex geometries. Our intentional application is to study the phenomena of explosive cavity formation and collapse. However, the same methods should also be applicable to simulation of bursts shallow enough to produce craters, and perhaps even of airbursts in situations where soil overburden is important. We have placed primary emphasis on test bed construction methods and on accurate measurement of the ground shock produced by the explosions. 8 refs., 7 figs.

Gaffney, E.S.; Wohletz, K.H.; House, J.W.; Brown, J.A.

1987-01-01

130

Detection of explosives with laser-induced breakdown spectroscopy  

NASA Astrophysics Data System (ADS)

Our recent work on the detection of explosives by laser-induced breakdown spectroscopy (LIBS) is reviewed in this paper. We have studied the physical mechanism of laser-induced plasma of an organic explosive, TNT. The LIBS spectra of TNT under single-photon excitation are simulated using MATLAB. The variations of the atomic emission lines intensities of carbon, hydrogen, oxygen, and nitrogen versus the plasma temperature are simulated too. We also investigate the time-resolved LIBS spectra of a common inorganic explosive, black powder, in two kinds of surrounding atmospheres, air and argon, and find that the maximum value of the O atomic emission line SBR of black powder occurs at a gate delay of 596 ns. Another focus of our work is on using chemometic methods such as principle component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) to distinguish the organic explosives from organic materials such as plastics. A PLS-DA model for classification is built. TNT and seven types of plastics are chosen as samples to test the model. The experimental results demonstrate that LIBS coupled with the chemometric techniques has the capacity to discriminate organic explosive from plastics.

Wang, Qian-Qian; Liu, Kai; Zhao, Hua; Ge, Cong-Hui; Huang, Zhi-Wen

2012-12-01

131

Experimental and numerical analyses of explosive free forming  

Microsoft Academic Search

Explosive forming of metal blanks is accompanied by large plastic deformations at high strain rates. Mathematical models which include all of the variables in a complete rigorous manner do not exist. However, different aspects of the problem may be dealt width using numerical approximations. These analyses can be used to predict process parameters and can be used to eliminate most

S. A. A. Akbari Mousavi; M. Riahi; A. Hagh Parast

2007-01-01

132

Moderate Velocity Ball Impact of a Mock High-Explosive  

Microsoft Academic Search

Modeling of thermal and mechanical events in high-explosive materials is complicated by the composite nature of the material, which experiences viscoelastic and plastic deformations and sustains damage in the form of microcracks that can dominate its overall behavior. A mechanical event of interest is projectile interaction with the material, which leads to extreme local deformation and adiabatic heating, which can

Jevan Furmanski; Philip Rae; Bradford E. Clements

2012-01-01

133

Explosives detection with quadrupole resonance analysis  

NASA Astrophysics Data System (ADS)

The increase in international terrorist activity over the past decade has necessitated the exploration of new technologies for the detection of plastic explosives. Quadrupole resonance analysis (QRA) has proven effective as a technique for detecting the presence of plastic, sheet, and military explosive compounds in small quantities, and can also be used to identify narcotics such as heroin and cocaine base. QRA is similar to the widely used magnetic resonance (MR) and magnetic resonance imaging (MRI) techniques, but has the considerable advantage that the item being inspected does not need to be immersed in a steady, homogeneous magnetic field. The target compounds are conclusively identified by their unique quadrupole resonance frequencies. Quantum magnetics has develop and introduced a product line of explosives and narcotics detection devices based upon QRA technology. The work presented here concerns a multi-compound QRA detection system designed to screen checked baggage, cargo, and sacks of mail at airports and other high-security facilities. The design philosophy and performance are discussed and supported by test results from field trials conducted in the United States and the United Kingdom. This detection system represents the current state of QRA technology for field use in both commercial and government sectors.

Rayner, Timothy J.; Thorson, Benjamin D.; Beevor, Simon; West, Rebecca; Krauss, Ronald A.

1997-02-01

134

Cotton Gin Dust Explosibility Determinations  

E-print Network

Following the recent Imperial sugar dust explosion in 2008, a comprehensive survey of past dust explosions was conducted by the Occupational Safety and Health Administration (OSHA) to determine potential explosible dusts. After the survey, OSHA...

Vanderlick, Francis Jerome

2014-01-06

135

Coal dust explosibility  

Microsoft Academic Search

This paper reports US Bureau of Mines (USBM) research on the explosibility of coal dusts. The purpose of this work is to improve safety in mining and other industries that process or use coal. Most of the tests were conducted in the USBM 20 litre laboratory explosibility chamber. The laboratory data show relatively good agreement with those from full-scale experimental

Kenneth L. Cashdollar

1996-01-01

136

Inside an Explosion  

NSDL National Science Digital Library

From afar, an explosion may seem like one of the most incredible examples of chaotic interaction. But once you look closer, as in this video from QUEST, you will find that large-scale explosions require very precise interactions to occur in just the right sequence.

2009-08-20

137

Query Nuclear Explosions Database  

NSDL National Science Digital Library

NUCEXP, National Geoscience Database, provided by the Australian Geological Survey Organization (AGSO), contains entries on nuclear explosions around the world since 1945, with the location, time and size of explosions. To view the records, users must select site and country conducting the test and beginning/end dates.

2002-01-01

138

The Cambrian Explosion  

NSDL National Science Digital Library

This University of Bristol page discusses in detail the Cambrian Explosion event that occurred about 545 million years ago. This site covers what the 'explosion' was and when it happened, the Cambrian environment, what caused this event to occur, fossil groups and their significance, and controversies surrounding this theory as well as recent discoveries.

139

Non-detonable explosive simulators  

DOEpatents

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

Simpson, Randall L. (Livermore, CA); Pruneda, Cesar O. (Livermore, CA)

1994-01-01

140

Non-detonable explosive simulators  

DOEpatents

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

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

1994-11-01

141

Micro-Gap Experiments and Insensitive Explosives  

NASA Astrophysics Data System (ADS)

Early research on shock desensitized plastic-bonded explosives (circa 1970) also studied large single crystals of explosive. High quality crystals --- free from voids that serve as nucleation sites for hot spots --- have been found to be very insensitive to shock initiation. In fact, experiments were not able to initiate a large single crystal of HMX (˜ 10,m) with a detonation wave in PBX 9404, which is 94 weight,% HMX and has a Chapman-Jouget pressure of 35,Pa. Yet a single crystal of HMX can be initiated by a flyer plate that drives a shock at a similar pressure. This is especially puzzling since the detonation wave in PBX 9404 has a peak pressure at the von Neumann spike of nearly 60,Pa. An important difference between the two drive systems is a small gap at the PBX 9404/HMX interface due to surface roughness of the PBX; estimated to be 30 to 50 microns. Conceptually, the experiment is equivalent to the gap test used to compare the sensitivity of different explosives; albeit with a micro-gap and a very insensitive explosive. The inability of a PBX 9404 detonation wave to initiate a single crystal of HMX is due to the reaction zone in the PBX 9404 being of comparable length to the gap in the experiment and the rarefaction or Taylor wave behind the detonation wave.

Menikoff, Ralph

2007-06-01

142

Micro-Gap Experiments and Insensitive Explosives  

NASA Astrophysics Data System (ADS)

Early research on shock desensitized plastic-bonded explosives (circa 1970) also studied large single crystals of explosive. High quality crystals—free from voids that serve as nucleation sites for hot spots—have been found to be very insensitive to shock initiation. In fact, experiments were not able to initiate a 10 mm crystal of HMX with a detonation wave in PBX 9404, which is 94 weight% HMX. Yet a single crystal of the same size can be initiated by a flyer plate that drives a shock wave at about the Chapman-Jouguet pressure of PBX 9404 or 35 GPa. This is especially puzzling since the detonation wave in PBX 9404 has a peak pressure at the von Neumann spike of nearly 60 GPa. An important difference between the two drive systems is a small gap at the PBX 9404/HMX interface due to surface roughness of the PBX; estimated to be about 30 microns. Conceptually, the experiment is equivalent to the gap test used to compare the sensitivity of explosives; albeit with a micro-gap and a very insensitive explosive. The inability of a PBX 9404 detonation wave to initiate a single crystal of HMX is due to the reaction zone in the PBX 9404 being of comparable length to the gap and the rarefaction or Taylor wave behind the detonation front.

Menikoff, Ralph

2007-12-01

143

Optically measured explosive impulse  

NASA Astrophysics Data System (ADS)

An experimental technique is investigated to optically measure the explosive impulse produced by laboratory-scale spherical charges detonated in air. Explosive impulse has historically been calculated from temporal pressure measurements obtained via piezoelectric transducers. The presented technique instead combines schlieren flow visualization and high-speed digital imaging to optically measure explosive impulse. Prior to an explosive event, schlieren system calibration is performed using known light-ray refractions and resulting digital image intensities. Explosive charges are detonated in the test section of a schlieren system and imaged by a high-speed digital camera in pseudo-streak mode. Spatiotemporal schlieren intensity maps are converted using an Abel deconvolution, Rankine-Hugoniot jump equations, ideal gas law, triangular temperature decay profile, and Schardin's standard photometric technique to yield spatiotemporal pressure maps. Temporal integration of individual pixel pressure profiles over the positive pressure duration of the shock wave yields the explosive impulse generated for a given radial standoff. Calculated explosive impulses are shown to exhibit good agreement between optically derived values and pencil gage pressure transducers.

Biss, Matthew M.; McNesby, Kevin L.

2014-06-01

144

Fast Internal Temperature Measurements in PBX9501 Thermal Explosions  

NASA Astrophysics Data System (ADS)

We have made spatially and temporally resolved temperature measurements internal to a thermal explosion in PBX9501, which is a plastic bonded explosive composed of 95% HMX and 2.5% estane mixed with 2.5% nitroplasticizer (BDNPA/F). In order to study the evolution of ignition in a thermally treated piece of explosive, we have pushed the time resolution of several different temperature diagnostics. In this paper, we will discuss the details of the time response of these diagnostics including temperature uncertainties. The temperature measurements are made both by thermocouples with corrections applied to compensate for the thermocouple response time and with optical pyrometry. An additional goal of adding high energy radiography diagnostics to future experiments has motivated an effort to synchronize thermal explosions to an external clock. In this paper, I discuss our current capabilities for controlling and measuring the development of an ignition within a piece of heated PBX9501.

Smilowitz, L.; Henson, B. F.; Sandstrom, M. M.; Asay, B. W.; Oschwald, D. M.; Romero, J. J.; Novak, A. M.

2006-07-01

145

Performance evaluation of HSLA steel subjected to underwater explosion  

NASA Astrophysics Data System (ADS)

Performance evaluation of High Strength Low Alloy (HSLA) steel subjected to underwater explosion is of interest to materials engineers because of its structural applications in ships and submarines. Circular and rectangular plates were investigated for their explosive response because they represent panels of a ships plating. Underwater explosion bulge tests were carried out with increasing shock intensity on 4 mm thick circular plates of 290 mm diameter and rectangular plates of 300×250 mm to study the plastic deformation and the onset of fracture. Empirical models were developed for the prediction of depth of bulge of the plates. A fresh set of tests with various explosive charge quantities and stand offs were carried out which showed good agreement with the models. Failed edges of the plate showed slant fracture suggesting ductile mode of failure. Scanning Electron Microscopic (SEM) fractographic examination showed dimple features suggesting micro void coalescence.

Rajendran, R.; Narashimhan, K.

2001-02-01

146

Simulation of high explosive explosion using adaptive material point method  

Microsoft Academic Search

Numerical simulation of high explosive explosion problems is a big challenge to traditional numerical methods because explosion usually involves ex- tremely large deformation and multi-material interaction of different phases. Re- centlydevelopedmeshfreemethodsshowmuchadvantagesovermesh-basedmethod for problems associated with very large deformation. Some of them have been successfully applied to impact and explosion problems, such as smoothed particle hydrodynamics (SPH). Similar to SPH, material

Shang Ma; Xiong Zhang; Yanping Lian; Xu Zhou

2009-01-01

147

Lithium niobate explosion monitor  

DOEpatents

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

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

1990-01-09

148

Lithium niobate explosion monitor  

DOEpatents

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

Bundy, Charles H. (Clearwater, FL); Graham, Robert A. (Los Lunas, NM); Kuehn, Stephen F. (Albuquerque, NM); Precit, Richard R. (Albuquerque, NM); Rogers, Michael S. (Albuquerque, NM)

1990-01-01

149

The Pinch Explosion  

E-print Network

THE PINCH EXPLOSION DAVID BOLAND Technology Manager A.P. ROSSITER President ICI-TENSA Services Houston, Texas ABSTRACT* A dramatic growth in the range of applications of pinch technology has been seen in recent years. These include...

Rossiter, A. P.; Boland, D.

150

Idaho Explosive Detection System  

ScienceCinema

Learn how INL researchers are making the world safer by developing an explosives detection system that can inspect cargo. For more information about INL security research, visit http://www.facebook.com/idahonationallaboratory

Klinger, Jeff

2013-05-28

151

Explosive Collisions at RHIC?  

E-print Network

Motivated by experimental results from RHIC, we suggest how a condensate for the Polyakov loop might produce explosive behavior at the QCD phase transition. This is due to a rapid rollover of the condensate field below the transition temperature.

Adrian Dumitru; Robert D. Pisarski

2001-02-02

152

Disorder induces explosive synchronization  

E-print Network

We study explosive synchronization, a phenomenon characterized by first-order phase transitions between incoherent and synchronized states in networks of coupled oscillators. While explosive synchronization has been the subject of many recent studies, in each case strong conditions on either the heterogeneity of the network, its link weights, or its initial construction are imposed to engineer a first-order phase transition. This raises the question of how robust explosive synchronization is in view of more realistic structural and dynamical properties. Here we show that explosive synchronization can be induced in mildly heterogeneous networks by the addition of quenched disorder to the oscillators' frequencies, demonstrating that it is not only robust to, but moreover promoted by, this natural mechanism. We support these findings with numerical and analytical results, presenting simulations of a real neural network as well as a self-consistency theory used to study synthetic networks.

Per Sebastian Skardal; Alex Arenas

2014-04-03

153

Idaho Explosives Detection System  

SciTech Connect

The Idaho Explosives Detection System (IEDS) was developed at the Idaho National Laboratory (INL) to respond to threats imposed by delivery trucks 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-minute measurement time. System performance was successfully demonstrated with explosives at the INL in June 2004 and at Andrews Air Force Base in July 2004.

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

2004-10-01

154

Idaho Explosive Detection System  

SciTech Connect

Learn how INL researchers are making the world safer by developing an explosives detection system that can inspect cargo. For more information about INL security research, visit http://www.facebook.com/idahonationallaboratory

Klinger, Jeff

2011-01-01

155

Explosion suppression system  

DOEpatents

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

Sapko, Michael J. (Finleyville, PA); Cortese, Robert A. (Pittsburgh, PA)

1992-01-01

156

Parametric Explosion Spectral Model  

SciTech Connect

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.

Ford, S R; Walter, W R

2012-01-19

157

Explosive Nucleosynthesis: Prospects  

E-print Network

Explosive nucleosynthesis is a combination of the nuclear physics of thermonuclear reactions, and the hydrodynamics of the plasma in which the reactions occur. It depends upon the initial conditions---the stellar evolution up to the explosive instability, and the nature of the explosion mechanism. Some key issues for explosive nucleosynthesis are the interaction of burning with hydrodynamics, the degree of microscopic mixing in convective zones, and the breaking of spherical symmetry by convection and rotation. Recent experiments on high intensity lasers provides new opportunities for laboratory testing of astrophysical hydrodynamic codes. Implications of SN1987A, SN1998bw (GRB980425?), and eta Carina are discussed, as well as the formation of black holes or neutron stars.

David Arnett

1999-08-16

158

The Combustion of Explosives  

NASA Astrophysics Data System (ADS)

The safe use of energetic materials has been scientifically studied for over 100 years. Even with this long history of scientific inquiry, the level of understanding of the important phenomena in accidental initiations of high explosives remains inadequate to predict the response to all possible thermal and mechanical (impact) scenarios. The search also continues for more ideal explosives and propellants that perform well yet are insensitive. Once ignition occurs in an explosive, the question becomes what the resulting violence will be. The classical view is that simple wave propagation proceeds from the ignition point. Recently, several experiments have elucidated the importance of reactive cracks involved in reaction violence in both thermally ignited experiments and impacted explosives, in contract to classical assumptions. This work presents a view of reaction violence, in both thermal and mechanical insults, that argues for the importance of reactive cracks, rather than simple wave propagation processes. Recent work in this area will be reviewed and presented.

Son, Steven F.

2001-06-01

159

Direct real-time detection of vapors from explosive compounds.  

PubMed

The real-time detection of vapors from low volatility explosives including PETN, tetryl, RDX, and nitroglycerine along with various compositions containing these substances was demonstrated. This was accomplished with an atmospheric flow tube (AFT) using a nonradioactive ionization source coupled to a mass spectrometer. Direct vapor detection was accomplished in less than 5 s at ambient temperature without sample preconcentration. The several seconds of residence time of analytes in the AFT provided a significant opportunity for reactant ions to interact with analyte vapors to achieve ionization. This extended reaction time, combined with the selective ionization using the nitrate reactant ions (NO3(-) and NO3(-)·HNO3), enabled highly sensitive explosives detection from explosive vapors present in ambient laboratory air. Observed signals from diluted explosive vapors indicated detection limits below 10 ppqv using selected ion monitoring (SIM) of the explosive-nitrate adduct at m/z 349, 378, 284, and 289 for tetryl, PETN, RDX, and NG, respectively. Also provided is a demonstration of the vapor detection from 10 different energetic formulations sampled in ambient laboratory air, including double base propellants, plastic explosives, and commercial blasting explosives using SIM for the NG, PETN, and RDX product ions. PMID:24090362

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

2013-11-19

160

( 'tams Dlvllan LSPE EXPLOSIVE PACKAGE  

E-print Network

~ ( ·'tams Dlvl·lan LSPE EXPLOSIVE PACKAGE STOWAGE THERMAL CONSTRAINTS LSPE EXPLOSIVE PACKAGE presents the study of LSPE High Explosive Package and transport frame stowage thermal constraints subsequent to LM touchdown and prior to lunar deployment. Approved by: #12;LSPE EXPLOSIVE PACKAGE STOWAGE

Rathbun, Julie A.

161

Coal mine explosions: seasonal trends.  

PubMed

An analysis of disaster reports on coal mine explosions indicates that gas explosions are randomly distributed throughout the year, whereas dust explosions (which may or may not be triggered by a gas explosion) occur with greater frequency during the dry fall and winter months. The lack of adequate moisture during cold weather tends to increase the rate and severity of the dust explosions. PMID:17832768

Kissell, F N; Nagel, A E; Zabetakis, M G

1973-03-01

162

Introduction Explosions in evolution problems The explosion time Stochastic Differential Equations with explosions  

E-print Network

Introduction Explosions in evolution problems The explosion time Stochastic Differential Equations with explosions Pablo Groisman University of Buenos Aires Joint work with J. Fern´andez Bonder, UBA J.D. Rossi, UBA ERPEM, November 29th, 2006 Pablo Groisman UBA Stochastic Differential Equations with explosions

Groisman, Pablo

163

Plastic brains.  

PubMed

Memories fade, alas, and more rapidly with age, though the aging brain holds more tenaciously to the longer past. Or does it? The brain may be continually editing those seemingly clear memories. That the immature brain constructs, "sculpts" itself by configuring its neural linkages to make best use of the sensory input received in early life has been known for decades. The more recent news is that mature brains also re-arrange these linkages as sensory inputs change. So what? Well, by some estimates inadequate stimulation in early childhood leaves 25% of Canadians neurally challenged by the modern world. Countries with systematic early child development programs show better results. Are there also opportunities for exploiting the plasticity of adult brains? (Or is that already happening, all around us?). PMID:19305751

Evans, Robert G

2007-08-01

164

Non-detonable and non-explosive explosive simulators  

DOEpatents

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

Simpson, Randall L. (Livermore, CA); Pruneda, Cesar O. (Livermore, CA)

1997-01-01

165

Non-detonable and non-explosive explosive simulators  

DOEpatents

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

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

1997-07-15

166

Surface properties of potential plastic-bonded explosives (PBX)  

Microsoft Academic Search

A technique that measures the work of dewetting of a poly-coated glass slide using a liquid of known surface tension is described. The resultant data are analyzed using solvent pairs that give calculated values for solid-surface tension of the polymers. The solid-surface tension of a pressed TATB plate is similarly measured, and values for interfacial tension and work of adhesion

T. Rivera; M. L. Matuszak

1983-01-01

167

Surface properties of potential plastic-bonded explosives (PBX)  

SciTech Connect

A technique that measures the work of dewetting of a poly-coated glass slide using a liquid of known surface tension is described. The resultant data are analyzed using solvent pairs that give calculated values for solid-surface tension of the polymers. The solid-surface tension of a pressed TATB plate is similarly measured, and values for interfacial tension and work of adhesion between polymer and TATB are computed based on the experimental data. Resulting values can be used as a scale to evaluate potential TATB binders. 13 references, 4 tables.

Rivera, T.; Matuszak, M.L.

1983-05-01

168

Shear Band Formation in Plastic-Bonded Explosives (PBX)  

NASA Astrophysics Data System (ADS)

Adiabatic shear bands can be a source of ignition and lead to detonation. At low to moderate deformation rates, 10--1000 s-1, two other mechanisms can also give rise to shear bands. These mechanisms are: softening caused by micro-cracking and (2) a constitutive response with a non-associated flow rule as is observed in granular material such as soil. Brittle behavior at small strains and the granular nature of HMX suggest that PBX-9501 constitutive behavior may be similar to sand. A constitutive model for each of these mechanims is studied in a series of calculations. A viscoelastic constitutive model for PBX-9501 softens via a statistical crack model, based on the work of Dienes (1986). A sand model is used to provide a non-associated flow rule. Both models generate shear band formation at 1--2% strain at nominal strain rates at and below 1000 s-1. Shear band formation is suppressed at higher strain rates. The sand model gives qualitative agreement for location and orientation of shear bands observed in a punch experiment. Both mechanisms may accelerate the formation of adiabatic shear bands.

Dey, Thomas N.; Johnson, James N.

1997-07-01

169

Shear band formation in plastic bonded explosive (PBX)  

NASA Astrophysics Data System (ADS)

Adiabatic shear bands can be a source of ignition and lead to detonation. At low to moderate deformation rates, 10-1000 s-1, two other mechanisms can also give rise to shear bands. These mechanisms are: 1) softening caused by micro-cracking and 2) a constitutive response with a non-associated flow rule as is observed in granular material such as soil. Brittle behavior at small strains and the granular nature of HMX suggest that PBX-9501 constitutive behavior may be similar to sand. A constitutive model for the first of these mechanisms is studied in a series of calculations. This viscoelastic constitutive model for PBX-9501 softens via a statistical crack model. A sand model is used to provide a non-associated flow rule and detailed results will be reported elsewhere. Both models generate shear band formation at 1-2% strain at nominal strain rates at and below 1000 s-1. Shear band formation is suppressed at higher strain rates. Both mechanisms may accelerate the formation of adiabatic shear bands.

Dey, T. N.; Johnson, J. N.

1998-07-01

170

A real explosion: the requirement of steam explosion pretreatment.  

PubMed

The severity factor is a common term used in steam explosion (SE) pretreatment that describes the combined effects of the temperature and duration of the pretreatment. However, it ignores the duration of the explosion process. This paper describes a new parameter, the explosion power density (EPD), which is independent of the severity factor. Furthermore, we present the adoption of a 5m(3) SE model for a catapult explosion mode, which completes the explosion within 0.0875 s. The explosion duration ratio of this model to a conventional model of the same volume is 1:123. The comparison between the two modes revealed a qualitative change by explosion speed, demonstrating that this real explosion satisfied the two requirements of consistency, and suggested a guiding mechanism for the design of SE devices. PMID:22858504

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

2012-10-01

171

Twinning, texture and constitutive relations for explosively formed jets  

SciTech Connect

We have used crystallographic-texture calculations to simulate the evolution of preferred grain orientations, and the corresponding changes in anisotropic plasticity, during explosively-driven liner collapse in metallic shaped-charge jets. For hcp metals, twinning tends to be an important deformation mechanism, and twinning is known to be strongly influenced by shocks. We consider cases of enhanced and inhibited twinning for titanium and titanium-alloys; the consequences of these treatments for the evolution of plasticity in early jet formation are discussed. 10 refs., 3 figs., 1 tab.

Schiferl, S.K.

1989-01-01

172

Microcantilever detector for explosives  

DOEpatents

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

Thundat, Thomas G. (Knoxville, TN)

1999-01-01

173

Microcantilever detector for explosives  

DOEpatents

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

Thundat, T.G.

1999-06-29

174

Direct Real-Time Detection of Vapors from Explosive Compounds  

SciTech Connect

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

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

2013-10-03

175

Hydrogen explosion testing with a simulated transuranic drum  

SciTech Connect

Transuranic (TRU) waste generated at the Savannah River Site (SRS) is currently stored onsite for future retrieval and permanent disposal at the Waste Isolation Pilot Plant (WIPP). Some of the TRU waste is stored in vented 210-liter (55-gallon) drums and consists of gloves, wipes, plastic valves, tools, etc. Gas generation caused by radiolysis and biodegradation of these organic waste materials may produce a flammable hydrogen-air mixture (>4% v/v) in the multi-layer plastic waste bags. Using a worst case scenario, a drum explosion test program was carried out to determine the hydrogen concentration necessary to cause removal of the drum lid. Test results indicate an explosive mixture up to 15% v/v of hydrogen can be contained in an SRS TRU drum without total integrity failure via lid removal.

Dykes, K.L.; Meyer, M.L.

1990-01-01

176

Hydrogen explosion testing with a simulated transuranic drum  

SciTech Connect

Transuranic (TRU) waste generated at the Savannah River Site (SRS) is currently stored onsite for future retrieval and permanent disposal at the Waste Isolation Pilot Plant (WIPP). Some of the TRU waste is stored in vented 210-liter (55-gallon) drums and consists of gloves, wipes, plastic valves, tools, etc. Gas generation caused by radiolysis and biodegradation of these organic waste materials may produce a flammable hydrogen-air mixture (>4% v/v) in the multi-layer plastic waste bags. Using a worst case scenario, a drum explosion test program was carried out to determine the hydrogen concentration necessary to cause removal of the drum lid. Test results indicate an explosive mixture up to 15% v/v of hydrogen can be contained in an SRS TRU drum without total integrity failure via lid removal.

Dykes, K.L.; Meyer, M.L.

1990-12-31

177

Managing the data explosion  

USGS Publications Warehouse

The 'data explosion' brought on by electronic sensors and automatic samplers can strain the capabilities of existing water-quality data-management systems just when they're needed most to process the information. The U.S. Geological Survey has responded to the problem by setting up an innovative system that allows rapid data analysis.

Hooper, Richard P.; Aulenbach, Brent T.

1993-01-01

178

Environmental fate of explosives  

Microsoft Academic Search

Waste disposal practices associated with military production of weapons, especially before and during World War II, have resulted in significant contamination of soils and ground water with high explosives such as TNT, RDX and HMX. Development of remediation and risk management strategies for these contaminated sites as well as development of approaches for sustainable use of active training and weapons

Judith C. Pennington; James M. Brannon

2002-01-01

179

Explosive Z Pinch  

E-print Network

We propose an explanation for the recently observed powerful contained explosion in a Z pinch experiment performed at Sandia National Laboratories. Our arguments are based on the assumption that a pure SU(2) Yang-Mills theory of scale $\\sim 0.5 $MeV is responsible for the emergence of the electron and its neutrino.

Francesco Giacosa; Ralf Hofmann; Markus Schwarz

2006-04-20

180

CBC: Halifax Explosion  

NSDL National Science Digital Library

In the evening of December 6, 1917, a massive explosion rocked the harbor of the rapidly growing city of Halifax, Nova Scotia, located in eastern Canada. Caused by the collision of two ships (one of which was carrying a tremendous amount of explosive material), the explosion killed over 1500 people outright, and devastated the settlements around the area. Working with various historical groups, the Canadian Broadcasting Corporation has created this engrossing multimedia look into the events leading up to that dreadful incident, along with offering a broader historical perspective on the development of the city of Halifax and the aftermath of these tragic events. Starting from the main page, visitors will learn about Halifax's history, along with having the opportunity to view significant interactive features, such as maps of the area and recently-discovered archival footage of the city and its environs. The interactive features here are quite amazing, as visitors can view video clips of survivors' recollections, and watch footage of various commemoration activities associated with the explosion.

181

Portable raman explosives detection  

SciTech Connect

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

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

2008-01-01

182

Explosions During Galaxy Formation  

NASA Astrophysics Data System (ADS)

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

Martel, H.; Shapiro, P. R.

2001-03-01

183

The Combustion of Explosives  

NASA Astrophysics Data System (ADS)

The safe use of energetic materials has been scientifically studied for over 100 years. Even with this long history of scientific inquiry, the level of understanding of the important deflagration phenomena in accidental initiations of high explosives remains inadequate to predict the response to possible thermal and mechanical (impact) scenarios. The search also continues for improved explosives and propellants that perform well, yet are insensitive. Currently, the most significant uncertainties are in the processes immediately following ignition. Once ignition occurs in an explosive, the question then becomes what the resulting violence will be. The classical view is that simple wave propagation proceeds from the ignition point. Recently, several experiments have elucidated the importance of reactive cracks involved in reaction violence in both thermally ignited experiments and impacted explosives, in contrast to classical assumptions. This paper presents a view of reaction violence, in both thermal and mechanical insults, that argues for the importance of reactive cracks, rather than simple wave propagation processes. Recent work in this area will be reviewed and presented. Initial results involving novel energetic materials will also be discussed. Novel materials may yield insight into the mechanisms involved with rapid deflagration processes.

Son, S. F.

2002-07-01

184

Phytoremediation of Selected Explosives  

Microsoft Academic Search

The phytoremediation of trinitrotoluene (TNT), nitroglycerine (NG) and pentaerytritoltetranitrate (PETN) using in vitrocultures of Rheum palmatum, Saponaria officinalisand Populus simonii were studied. All above mentioned explosives were degradated to less toxic products and finally probably bound to the cell wall or further involved in the metabolism. The formation of trinitrobenzene (TNB) during degradation of TNT which is a product of

T. Van?k; A. Nepovím; R. Podlipná; S. Zeman; M. Vágner

2003-01-01

185

Determining the effects of routine fingermark detection techniques on the subsequent recovery and analysis of explosive residues on various substrates.  

PubMed

An offender who has recently handled bulk explosives would be expected to deposit latent fingermarks that are contaminated with explosive residues. However, fingermark detection techniques need to be applied in order for these fingermarks to be detected and recorded. Little information is available in terms of how routine fingermark detection methods impact on the subsequent recovery and analysis of any explosive residues that may be present. If an identifiable fingermark is obtained and that fingermark is found to be contaminated with a particular explosive then that may be crucial evidence in a criminal investigation (including acts of terrorism involving improvised explosive devices). The principal aims of this project were to investigate: (i) the typical quantities of explosive material deposited in fingermarks by someone who has recently handled bulk explosives; and (ii) the effects of routine fingermark detection methods on the subsequent recovery and analysis of explosive residues in such fingermarks. Four common substrates were studied: paper, glass, plastic (polyethylene plastic bags), and metal (aluminium foil). The target explosive compounds were 2,4,6-trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), as well as chlorate and nitrate ions. Recommendations are provided in terms of the application of fingermark detection methods on surfaces that may contain explosive residues. PMID:24314527

King, Sam; Benson, Sarah; Kelly, Tamsin; Lennard, Chris

2013-12-10

186

Explosive Percolation in Directed Networks  

E-print Network

Explosive Percolation in Directed Networks Diego Alcala and Katherine Sytwu With Shane Squires ­ Directed and undirected networks ­ Percolation ­ Explosive percolation · Methodology · Results · Conclusion, infrastructure, etc. · Grow by the addition of links · New class of transitions: "explosive percolation" Taken

Anlage, Steven

187

EXPLOSIONS AND ARBITRAGE IOANNIS KARATZAS  

E-print Network

EXPLOSIONS AND ARBITRAGE IOANNIS KARATZAS Abstract The Feller and Khas'minskii tests provide conditions, under which a given dif- fusion process X(·) in a domain D can have explosions. If such explosions happen with positive probability, what is the distribution F(t, x) = Px(S t) , 0

Columbia University

188

LSP EXPLOSIVE PACKAGES FRAGMENTATION STUDY  

E-print Network

ATM 1046 LSP EXPLOSIVE PACKAGES FRAGMENTATION STUDY Prepared by: ,11. 15. :n-~ G. B. Min Approved considerations the probability of fragments from an LSP explosive package striking the ALSEP Central Station Experiment requires that Explosive Charges be detonated on the luoar surface early in the ALSEP lunar mission

Rathbun, Julie A.

189

Hand held explosives detection system  

DOEpatents

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

Conrad, Frank J. (Albuquerque, NM)

1992-01-01

190

New explosive seam welding concepts  

NASA Technical Reports Server (NTRS)

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

Bement, L. J.

1973-01-01

191

Big Explosives Experimental Facility - BEEF  

ScienceCinema

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

None

2015-01-07

192

Big Explosives Experimental Facility - BEEF  

SciTech Connect

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

None

2014-10-31

193

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

NASA Astrophysics Data System (ADS)

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

Hurley, Christoph

194

Hidden explosives detector employing pulsed neutron and x-ray interrogation  

DOEpatents

Methods and systems for the detection of small amounts of modern, highly-explosive nitrogen-based explosives, such as plastic explosives, hidden in airline baggage. Several techniques are employed either individually or combined in a hybrid system. One technique employed in combination is X-ray imaging. Another technique is interrogation with a pulsed neutron source in a two-phase mode of operation to image both nitrogen and oxygen densities. Another technique employed in combination is neutron interrogation to form a hydrogen density image or three-dimensional map. In addition, deliberately-placed neutron-absorbing materials can be detected.

Schultz, F.J.; Caldwell, J.T.

1993-04-06

195

Detection of Explosives  

Microsoft Academic Search

\\u000a Since the development of modern analysis supported by electronic means several different methods are available for detection\\u000a of explosives, which have been improved within the last decades with regard to precision, reliability, quickness and minimum\\u000a test sample volume. These developments enable us to analyse substances very quickly - in some cases also on-line. The question\\u000a is, which methods are suitable

Hiltmar Schubert

196

QGP fireball explosion  

Microsoft Academic Search

We identify the major physics milestones in the development of strange\\u000ahadrons as an observable for both the formation of quark-gluon plasma, and of\\u000athe ensuing explosive disintegration of deconfined matter fireball formed in\\u000arelativistic heavy ion collisions at 160--20A GeV. We describe the physical\\u000aproperties of QGP phase and show agreement with the expectations based on an\\u000aanalysis of

J. Letessier; G. Torrieri; S. Hamieh; J. Rafelski

2000-01-01

197

Cast aluminized explosives (review)  

Microsoft Academic Search

This paper reviews the current status and future trends of aluminized explosives. The major focus is on cast compositions,\\u000a which encompass both the melt-cast trinitrotoluene (TNT) based and the slurry cast polymer-based compositions. Widely reported\\u000a RDX and HMX based aluminized compositions with TNT used as a binder are discussed in detail. Various researchers have suggested\\u000a a 15–20% Al content as

P. P. Vadhe; R. B. Pawar; R. K. Sinha; S. N. Asthana; A. Subhananda Rao

2008-01-01

198

Dust cluster explosion  

SciTech Connect

A model for the dust cluster explosion where micron/sub-micron sized particles are accelerated at the expense of plasma thermal energy, in the afterglow phase of a complex plasma discharge is proposed. The model is tested by molecular dynamics simulations of dust particles in a confining potential. The nature of the explosion (caused by switching off the discharge) and the concomitant dust acceleration is found to depend critically on the pressure of the background neutral gas. At low gas pressure, the explosion is due to unshielded Coulomb repulsion between dust particles and yields maximum acceleration, while in the high pressure regime it is due to shielded Yukawa repulsion and yields much feebler acceleration. These results are in agreement with experimental findings. Our simulations also confirm a recently proposed electrostatic (ES) isothermal scaling relation, P{sub E}{proportional_to}V{sub d}{sup -2} (where P{sub E} is the ES pressure of the dust particles and V{sub d} is the confining volume).

Saxena, Vikrant [School of Mathematics and Physics, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Institute for Plasma Research, Bhat, Gandhinagar (India); Avinash, K. [Department of Physics and Astrophysics, University of Delhi, New Delhi (India); Sen, A. [Institute for Plasma Research, Bhat, Gandhinagar (India)

2012-09-15

199

New plastic joints for plastic orthoses  

Microsoft Academic Search

Plastic joints for orthoses have more advantages than metal joints. They are lightweight, noiseless comfortable to use, rust proof, corrosion free, and radiolucent. Two types of plastic joints were developed by the authors, one for the ankle joint and the other for the knee joint, elbow joint or hip joint. Polypropylene was chosen as the joint material because of its

H. WATANABE; T. KUTSUNA; H. MORINAGA; T. OKABE

200

Metaplasticity: the plasticity of synaptic plasticity  

Microsoft Academic Search

In thi paper, we review experimental evidence for a novel form of persistent synaptic plasticity we call metaplasticity. Metaplasticity is induced by synaptic or cellular activity, but it is not necessarilly expressed as a change in the efficacy of normal synaptic transmission. Instead, it is manifest as a change in the ability to induce subsequent synaptic plasticity such as long-term

Wickliffe C. Abraham; Mark F. Bear

1996-01-01

201

Priming explosive devices  

Microsoft Academic Search

A special form of priming through toroidal waves for a projectile having a hollow charge is described. The priming is accomplished by an annular priming relay or booster, preferably frusto-conical in shape, placed in a seat made of an inert material, preferably a plastic, having low speed of transmission for shock waves. (6 claims)

Precoul

1969-01-01

202

Sensitivity of once-shocked, weathered high explosives  

SciTech Connect

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

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

1998-07-01

203

Particle characteristics of trace high explosives: RDX and PETN.  

PubMed

The sizes of explosives particles in fingerprint residues produced from C-4 and Semtex-1A were investigated with respect to a fragmentation model. Particles produced by crushing crystals of RDX and PETN were sized by using scanning electron microscopy, combined with image analysis, and polarized light microscopy was used for imaging and identifying explosive particles in fingerprint residues. Crystals of RDX and PETN fragment in a manner that concentrates mass in the largest particles of the population, which is common for a fragmentation process. Based on the fingerprints studied, the particle size to target for improving mass detection in fingerprint residues by ion mobility spectrometry (IMS) is > or = 10 microm in diameter. Although particles smaller than 10 microm in diameter have a higher frequency, they constitute < 20% of the total mass. Efforts to improve collection efficiency of explosives particles for detection by IMS, or other techniques, must take into consideration that the mass may be concentrated in a relatively few particles that may not be homogeneously distributed over the fingerprint area. These results are based on plastic-bonded explosives such as C-4 that contain relatively large crystals of explosive, where fragmentation is the main process leading to the presence of particles in the fingerprint residues. PMID:17316229

Verkouteren, Jennifer R

2007-03-01

204

Equations of State and High-Pressure Phases of Explosives  

NASA Astrophysics Data System (ADS)

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

Peiris, Suhithi M.; Gump, Jared C.

205

Find a Plastic Surgeon  

MedlinePLUS

... Shop ASPS Corporate Opportunities The PSF About Us Find a Plastic Surgeon Please provide search terms. ZIP ... by Procedure Filter by Procedure Do Your Homework Find a board-certified plastic surgeon you can trust ...

206

Ear Plastic Surgery  

MedlinePLUS

Ear Plastic Surgery Ear Plastic Surgery Patient Health Information News media interested in covering the latest from AAO-HNS/F can ... weight earrings. Does Insurance Pay for Cosmetic Ear Surgery? Insurance usually does not cover surgery solely for ...

207

Prompt Reaction of Aluminum in Detonating Explosives  

NASA Astrophysics Data System (ADS)

The potential of aluminum (Al) reaction to boost detonation energy has been studied for decades, most recently spurred by the availability of nanometer-sized particles. A literature review is consistent with results from the small-scale shock reactivity test (SSRT). In this test, <1/2-g samples in confinement are shock loaded on one end, and the output at the other end dents a soft witness block. For samples in which 0.3 g of cyclotetramethylenetetranitramine (HMX) was mixed with 8 ?m Al, the deepest dent occurred at 15% Al. When ammonium perchlorate (AP) was mixed with the same Al, the increased dents were consistent with changes in detonation velocity previously reported on similar mixtures. One outcome of this study is a new interpretation for the participation of Al in large scale gap tests on plastic-bonded explosives, which was discussed by Bernecker at this meeting in 1987.

Sandusky, H. W.; Granholm, R. H.

2006-07-01

208

Processing of plastics  

PubMed Central

An overview is given of the processing of plastic materials from the handling of polymers in the pellet and powder form to manufacturing of a plastic fabricated product. Various types of equipment used and melt processing ranges of various polymer formulations to make the myriad of plastic products that are commercially available are discussed. PMID:1175556

Spaak, Albert

1975-01-01

209

Migrability of PVC plasticizers  

Microsoft Academic Search

The ability of different PVC plasticizers to migrate towards a polymer in contact with flexible PVC has been investigated. A procedure based on the monitoring of the plasticizer concentration by infrared spectroscopy has been employed. The mathematical model applied to experimental data has permitted the calculation of average diffusion coefficients and, hence, a comparison among the plasticizers studied (citrates, phthalates

A. Marcilla; S. Garcia; J. C. Garcia-Quesada

2008-01-01

210

Sea of Plastic  

NSDL National Science Digital Library

Where do our used plastic cups, packaging and other plastic products go? In this audio report from QUEST produced by KQED, learn why some cities and counties are so concerned that they've passed ordinances to try to limit plastic consumption.

Kqed

2012-08-08

211

Tomorrow's Plastic World  

ERIC Educational Resources Information Center

Far from being just cheap packaging materials, plastics may be the materials of tomorrow. Plastic can conduct electricity, and this opens up a host of high-tech possibilities in the home and in energy generation. These possibilities are discussed here along with how plastic can be recycled and perhaps even grown.

Macdonald, Averil

2005-01-01

212

Epigenetics and Developmental Plasticity  

E-print Network

Epigenetics and Developmental Plasticity Across Species ABSTRACT: Plasticity is a typical feature of development and can lead to diver- gent phenotypes. There is increasing evidence that epigenetic mechanisms in developmental plasticity. Thus, in the context of the concept of developmental homology, epigenetic mechanisms

Champagne, Frances A.

213

Plastics in Building.  

ERIC Educational Resources Information Center

The evaluation and use of plastics in the construction industry are explained. The contributors offer extensive, timely, and thoroughly researched data on the chemistry, properties, functions, engineering behavior, and specific applications of plastics to building requirements. The major subjects discussed in depth are--(1) the role of plastics in…

Skeist, Irving, Ed.

214

Explosion Heat and Metal Acceleration Ability of High Explosives  

NASA Astrophysics Data System (ADS)

Investigations of explosion heats of TNT and HMX show that in tests of unconfined charges the explosion products undergo intense secondary heating when approaching the wall of calorimetric bomb cavity. This secondary heating causes "re-freezing" the explosion products in conditions of low pressure. An inert metal casing whose mass is more than four times greater than that of explosive charge prevents the secondary heating of products to the "re-freezing" temperature and rules out a change in their composition. Filling of calorimetric bomb cavity before explosion with an inert gas produces an effect similar to that of charge casing. The value of explosion heat, measured under conditions that preclude "re-freezing" of explosion products can serve as a measure of the energy content of high explosive. With the use of this parameter a simple method for predicting explosive performance in Cylinder Test has been developed. The method is based on the assumption that the coefficient of conversion of the chemical energy to the kinetic energy depends on the volumetric mole number of gaseous products.

Makhov, M. N.

2004-07-01

215

Effects of explosions in hard rocks  

SciTech Connect

This work relates to explosions in hard rocks (ex: basalt, granite, limestone{hor_ellipsis}). Hard rock masses typically have a blocky structure created by the existence of geologic discontinuities such as bedding contacts, faults, and joints. At very high pressure-hundreds of kilobars and above-these discontinuities do not act separately, and the rock appears to be an equivalent continuous medium. At stress of a few tens of kilobars and below, the geologic discontinuities control the kinematics of the rock masses. Hence, the simulation of rock dynamics, anywhere but in the very-near source region, should account for those kinematics. In the very high pressure range continuum-based analysis is appropriate. In the discrete motion range one could consider: an equivalent continuum approach with anisotropy and plasticity. However, this is unlikely to provide the right kinematics; embedding discontinuities in continuum models, such as using joint elements and slip surfaces in finite elements. Typically, these are limited in terms of the separation of elements which may reconnect arbitrarily to new elements; complete discrete methods; ex: discrete elements, discontinuous displacement analysis (DDA). Discrete elements have progressed further than DDA We have chosen to develop and apply discrete elements models to explosion phenomenology in rocks.

Heuze, F.E.; Walton, O.R.; Maddix, D.M.; Shaffer, R.J.; Butkovich, T.R.

1993-05-01

216

Biodegradability of Plastics  

PubMed Central

Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.). In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed. PMID:19865515

Tokiwa, Yutaka; Calabia, Buenaventurada P.; Ugwu, Charles U.; Aiba, Seiichi

2009-01-01

217

QGP fireball explosion  

E-print Network

We identify the major physics milestones in the development of strange hadrons as an observable for both the formation of quark-gluon plasma, and of the ensuing explosive disintegration of deconfined matter fireball formed in relativistic heavy ion collisions at 160--20A GeV. We describe the physical properties of QGP phase and show agreement with the expectations based on an analysis of hadron abundances. We than also demonstrate that the m_t shape of hadron spectra is in qualitative agreement with the sudden breakup of a supercooled QGP fireball.

J. Letessier; G. Torrieri; S. Hamieh; J. Rafelski

2000-11-13

218

Explosions on the Sun  

NASA Astrophysics Data System (ADS)

I describe two of the most dynamic and highly energetic phenomena in the Solar System - these are the eruptions and flaring that occur on the Sun. They can release as much energy as 10 million volcanoes, and throw out material into the solar system with similar mass to Mount Everest! The theories of what can produce such an explosion are based around the magnetic field that confines the gas. These events can produce emission right across the electromagnetic spectrum. The status of our ability to predict these events is discussed.

Harra, Louise K.

2005-10-01

219

Zirconium hydride containing explosive composition  

DOEpatents

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.

Walker, Franklin E. (18 Shadow Oak Rd., Danville, CA 94526); Wasley, Richard J. (4290 Colgate Way, Livermore, CA 94550)

1981-01-01

220

Neutrino Leakage and Supernova Explosion  

NASA Astrophysics Data System (ADS)

In the process of supernova explosion, the neutrino leakage is very important. With different neutrino leakage schemes, the type II supernova explosions are simulated respectively for the stars with the mass of 12 M_{?}, 14 M_{?}, and 15 M_{?} by using a one-dimensional spherically symmetric model. The results show that the different neutrino leakage schemes have influence on the supernova collapse, shock wave propagation, and explosion. And the best values of corrective parameters which are propitious to the type II supernova explosions are given. In addition, the impacts of the equation of state and the compression modulus on the simulating results are discussed.

Liao, D. B.; Zhang, M. J.; Li, Y.; Pan, J. H.; Chen, X.

2014-09-01

221

Explosive scabbling of structural materials  

DOEpatents

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

Bickes, Jr., Robert W. (Albuquerque, NM); Bonzon, Lloyd L. (Albuquerque, NM)

2002-01-01

222

Low voltage nonprimary explosive detonator  

DOEpatents

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

Dinegar, Robert H. (Los Alamos, NM); Kirkham, John (Newbury, GB2)

1982-01-01

223

Introduction Explosions in evolution problems Numerical approximations Adaptive numerical scheme Stochastic Differential Equations with explosions  

E-print Network

Introduction Explosions in evolution problems Numerical approximations Adaptive numerical scheme Stochastic Differential Equations with explosions Pablo Groisman University of Buenos Aires Joint work with J Stochastic Differential Equations with explosions #12;Introduction Explosions in evolution problems Numerical

Groisman, Pablo

224

Glassy metallic plastics  

NASA Astrophysics Data System (ADS)

This paper reports a class of bulk metallic glass including Ce-, LaCe-, CaLi-, Yb-, and Sr-based metallic glasses, which are regarded as glassy metallic plastics because they combine some unique properties of both plastics and metallic alloys. These glassy metallic plastics have very low glass transition temperature ( T g ˜25°C to 150°C) and low Young’s modulus (˜20 GPa to 35 GPa). Similar to glassy plastics, these metallic plastics show excellent plastic-like deformability on macro-, micro- and even nano-scale in their supercooled liquid range and can be processed, such as elongated, compressed, bent, and imprinted at low temperatures, in hot water for instance. Under ambient conditions, they display such metallic properties as high thermal and electric conductivities and excellent mechanical properties and other unique properties. The metallic plastics have potential applications and are also a model system for studying issues in glass physics.

Li, Jianfu; Wang, Junqiang; Liu, Xiaofeng; Zhao, Kun; Zhang, Bo; Bai, Haiyang; Pan, Mingxiang; Wang, Weihua

2010-03-01

225

Variations on the "Whoosh" Bottle Alcohol Explosion Demonstration Including Safety Notes  

NASA Astrophysics Data System (ADS)

The explosion or burning of methanol, ethanol, n-propanol, and isopropanol in large small-necked bottles when ignited with a match has been studied with respect to the nature of the alcohol, temperature, concentration dilutions with water, oxygen concentration, plastic versus glass bottles, and salts added for color. The various effects are explained in terms of vapor pressures. Safety guidelines are emphasized.

Fortman, John J.; Rush, Andrea C.; Stamper, Jennifer E.

1999-08-01

226

Aspects of dynamic recrystallization in shaped charge and explosively formed projectile devices  

Microsoft Academic Search

Under a shock wave, a shaped charge (SC) liner or an explosively formed projectile (EFP) device transforms into a jet and a slug. At various laboratories, it was found that the transformation was closely related to extensive plastic flow occurring at high strain rates. Along with the shape trans-formation, there is evidence of changes in hardness, strength, grain configuration, microstructure,

C. Feng; L. E. Murr; C.-S. Niou

1996-01-01

227

The vortex explosion transition  

NASA Astrophysics Data System (ADS)

In type-II superconductors an applied magnetic field B, between the lower and upper critical values, produces a mixed state containing Abrikosov vortices. These vortices contain a quantum of magnetic flux h/2e and consist of a core with depressed order parameter and a pattern of perpetually circulating supercurrents. When B is applied parallel to a thin film, the circulating supercurrents get squeezed by the film surfaces causing the vortex core to become unstable and explode all the way across the film when the thickness d is below the critical value of dc = 4.4?; here ? is the superconducting coherence length. For temperatures above the explosion condition dc(T) > d, the applied B cannot induce single parallel vortices, however perpendicular vortices can be generated spontaneously by thermal fluctuations. We observe a transition from non-dissipative to dissipative behavior at the explosion condition and find that the dynamics of the spontaneous perpendicular vortices can be tuned by the pairbreaking effect of the applied parallel field.

Kunchur, M. N.; Liang, M.; Gurevich, A.

2013-02-01

228

Controlled by Distant Explosions  

NASA Astrophysics Data System (ADS)

VLT Automatically Takes Detailed Spectra of Gamma-Ray Burst Afterglows Only Minutes After Discovery A time-series of high-resolution spectra in the optical and ultraviolet has twice been obtained just a few minutes after the detection of a gamma-ray bust explosion in a distant galaxy. The international team of astronomers responsible for these observations derived new conclusive evidence about the nature of the surroundings of these powerful explosions linked to the death of massive stars. At 11:08 pm on 17 April 2006, an alarm rang in the Control Room of ESO's Very Large Telescope on Paranal, Chile. Fortunately, it did not announce any catastrophe on the mountain, nor with one of the world's largest telescopes. Instead, it signalled the doom of a massive star, 9.3 billion light-years away, whose final scream of agony - a powerful burst of gamma rays - had been recorded by the Swift satellite only two minutes earlier. The alarm was triggered by the activation of the VLT Rapid Response Mode, a novel system that allows for robotic observations without any human intervention, except for the alignment of the spectrograph slit. ESO PR Photo 17a/07 ESO PR Photo 17a/07 Triggered by an Explosion Starting less than 10 minutes after the Swift detection, a series of spectra of increasing integration times (3, 5, 10, 20, 40 and 80 minutes) were taken with the Ultraviolet and Visual Echelle Spectrograph (UVES), mounted on Kueyen, the second Unit Telescope of the VLT. "With the Rapid Response Mode, the VLT is directly controlled by a distant explosion," said ESO astronomer Paul Vreeswijk, who requested the observations and is lead-author of the paper reporting the results. "All I really had to do, once I was informed of the gamma-ray burst detection, was to phone the staff astronomers at the Paranal Observatory, Stefano Bagnulo and Stan Stefl, to check that everything was fine." The first spectrum of this time series was the quickest ever taken of a gamma-ray burst afterglow, let alone with an instrument such as UVES, which is capable of splitting the afterglow light with uttermost precision. What is more, this amazing record was broken less than two months later by the same team. On 7 June 2006, the Rapid-Response Mode triggered UVES observations of the afterglow of an even more distant gamma-ray source a mere 7.5 minutes after its detection by the Swift satellite. Gamma-ray bursts are the most intense explosions in the Universe. They are also very brief. They randomly occur in galaxies in the distant Universe and, after the energetic gamma-ray emission has ceased, they radiate an afterglow flux at longer wavelengths (i.e. lower energies). They are classified as long and short bursts according to their duration and burst energetics, but hybrid bursts have also been discovered (see ESO PR 49/06). The scientific community agrees that gamma-ray bursts are associated with the formation of black holes, but the exact nature of the bursts remains enigmatic. ESO PR Photo 17b/07 ESO PR Photo 17b/07 Kueyen at Night Because a gamma-ray burst typically occurs at very large distances, its optical afterglow is faint. In addition, it fades very rapidly: in only a few hours the optical afterglow brightness can fade by as much as a factor of 500. This makes detailed spectral analysis possible only for a few hours after the gamma-ray detection, even with large telescopes. During the first minutes and hours after the explosion, there is also the important opportunity to observe time-dependent phenomena related to the influence of the explosion on its surroundings. The technical challenge therefore consists of obtaining high-resolution spectroscopy with 8-10 m class telescopes as quickly as possible. "The afterglow spectra provide a wealth of information about the composition of the interstellar medium of the galaxy in which the star exploded. Some of us even hoped to characterize the gas in the vicinity of the explosion," said team member Cédric Ledoux (ESO). ESO PR Photo 17c/07 ESO PR Photo 17c/07 The Kueyen Control Room

2007-03-01

229

Explosives Detection for Aviation Security  

Microsoft Academic Search

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

Anthony Fainberg

1992-01-01

230

The Scaled Thermal Explosion Experiment  

SciTech Connect

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

Wardell, J F; Maienschein, J L

2002-07-05

231

Trace Explosive Detection Using Nanosensors  

SciTech Connect

Selective and sensitive detection of explosives is very important in countering terrorist threats. Detecting trace explosives has become a very complex and expensive endeavor because of a number of factors, such as the wide variety of materials that can be used as explosives, the lack of easily detectable signatures, the vast number of avenues by which these weapons can be deployed, and the lack of inexpensive sensors with high sensitivity and selectivity. High sensitivity and selectivity, combined with the ability to lower the deployment cost of sensors using mass production, is essential in winning the war on explosives-based terrorism. Nanosensors have the potential to satisfy all the requirements for an effective platform for the trace detection of explosives.

Senesac, Larry R [ORNL; Thundat, Thomas George [ORNL

2008-01-01

232

Characterization of secondary grain dust explosions  

E-print Network

. Parnell, Jr. Presently, grain dust explosion research has been directed mainly into the mechanisms of the primary explosions with interest in the secondary explosion phenomena being virtually unrecord. ed. . Research 1n the area of' secondary grain... dust, explosions would provide new information as well as increase the understanding of the total dust explosion phenomena. This greater knowledge could potentially aid in the reduction of future grain dust explosions. This study on the mechanisms...

Schulman, Cheryl Wendler

1983-01-01

233

Crackling noise in plasticity  

NASA Astrophysics Data System (ADS)

Plastic deformation is a paradigmatic problem of multiscale materials modelling with relevant processes ranging from the atomistic scale up to macroscopic scales where deformation is treated by continuum mechanics. Recent experiments, investigating deformation fluctuations under conditions where plastic deformation was expected to occur in a smooth and stable manner, demonstrate that deformation is spatially heterogeneous and temporally intermittent, not only on atomic scales, where spatial heterogeneity is expected, but also on mesoscopic scales where plastic fluctuations involve collective events of widely different amplitudes. Evidence for crackling noise in plastic deformation comes from acoustic emission measurements and from deformation of micron-scale samples both in crystalline and amorphous materials. Here we provide a detailed account of our current understanding of crackling noise in crystal and amorphous plasticity stemming from experiments, computational models and scaling theories. We focus our attention on the scaling properties of plastic strain bursts and their interpretation in terms of non-equilibrium critical phenomena.

Alava, Mikko J.; Laurson, Lasse; Zapperi, Stefano

2014-10-01

234

Watersheds and Explosive percolation  

E-print Network

The recent work by Achlioptas, D'Souza, and Spencer opened up the possibility of obtaining a discontinuous (explosive) percolation transition by changing the stochastic rule of bond occupation. Despite the active research on this subject, several questions still remain open about the leading mechanism and the properties of the system. We review the largest cluster and the Gaussian models recently introduced. We show that, to obtain a discontinuous transition it is solely necessary to control the size of the largest cluster, suppressing the growth of a cluster differing significantly, in size, from the average one. As expected for a discontinuous transition, a Gaussian cluster-size distribution and compact clusters are obtained. The surface of the clusters is fractal, with the same fractal dimension of the watershed line.

Herrmann, Hans J

2011-01-01

235

Watersheds and Explosive percolation  

NASA Astrophysics Data System (ADS)

The recent work by Achlioptas, D'Souza, and Spencer opened up the possibility of obtaining a discontinuous (explosive) percolation transition by changing the stochastic rule of bond occupation. Despite the active research on this subject, several questions still remain open about the leading mechanism and the properties of the system. We review the largest cluster and the Gaussian models recently introduced. We show that, to obtain a discontinuous transition it is solely necessary to control the size of the largest cluster, suppressing the growth of a cluster di_ering significantly, in size, from the average one. As expected for a discontinuous transition, a Gaussian cluster-size distribution and compact clusters are obtained. The surface of the clusters is fractal, with the same fractal dimension of the watershed line.

Herrmann, Hans J.; Araujo, Nuno A. M.

236

Plasticized phenolphthalein polycarbonate  

NASA Technical Reports Server (NTRS)

Phenolphthalein polycarbonate was successfully plasticized with polychlorinated biphenyls (e.g., Aroclor 1231) or tricresyl phosphate and cast from tetrahydrofuran to give clear films without loss of fire resistance. At loadings of 20 to 30 percent plasticizer the Tg was lowered to approximately 100 C which would render phenolphthalein polycarbonate easily moldable. Although these materials had some mechanical integrity as shown by their film forming ability, the room temperature toughness of the plasticized polymer was not significantly improved over unmodified polymer.

Harrison, E. S.

1976-01-01

237

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

SciTech Connect

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

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

1999-03-01

238

On the violence of thermal explosion in solid explosives  

SciTech Connect

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

Chidester, S.K.; Tarver, C.M.; Green, L.G.; Urtiew, P.A. [Lawrence Livermore National Lab., CA (United States). Defense Technologies Engineering Div.] [Lawrence Livermore National Lab., CA (United States). Defense Technologies Engineering Div.

1997-07-01

239

Plastics and health risks.  

PubMed

By 2010, the worldwide annual production of plastics will surpass 300 million tons. Plastics are indispensable materials in modern society, and many products manufactured from plastics are a boon to public health (e.g., disposable syringes, intravenous bags). However, plastics also pose health risks. Of principal concern are endocrine-disrupting properties, as triggered for example by bisphenol A and di-(2-ethylhexyl) phthalate (DEHP). Opinions on the safety of plastics vary widely, and despite more than five decades of research, scientific consensus on product safety is still elusive. This literature review summarizes information from more than 120 peer-reviewed publications on health effects of plastics and plasticizers in lab animals and humans. It examines problematic exposures of susceptible populations and also briefly summarizes adverse environmental impacts from plastic pollution. Ongoing efforts to steer human society toward resource conservation and sustainable consumption are discussed, including the concept of the 5 Rs--i.e., reduce, reuse, recycle, rethink, restrain--for minimizing pre- and postnatal exposures to potentially harmful components of plastics. PMID:20070188

Halden, Rolf U

2010-01-01

240

Careers in Plastics  

NSDL National Science Digital Library

Teachers' Domain presents this video as part of a series on advanced technological education. Filmed at NPE: The International Plastics Showcase, the video features careers in the plastics industry. Degrees that lead to careers in plastics are discussed. The video also talks about emerging green technologies and how they relate to the plastics industry. The video may be viewed online or downloaded. To download the clip, users must create a free login for Teachers' Domain. Running time for this QuickTime video is 2:13. Educators will also find a background essay, discussion questions, and standards alignment for the material.

241

Plastic Race Car Competition  

NSDL National Science Digital Library

This video, presented by WGBH, looks at a high school outreach program to get students interested in plastic manufacturing by having them make plastic race cars. The students go through the entire process of design from both technical and hands-on perspectives. This video also serves as an overview of the different types of plastic manufacturing processes that are utilized in the industry. This video would be great for anyone interested in plastic manufacturing, or just looking to learn a little bit more about it. Educators will also find a background essay, discussion questions, and standards alignment for the material. Running time for the video is 4:32.

242

Shock desensitizing of solid explosive  

SciTech Connect

Solid explosive can be desensitized by a shock wave too weak to initiate it promptly, and desensitized explosive does not react although its chemical composition is almost unchanged. A strong second shock does not cause reaction until it overtakes the first shock. The first shock, if it is strong enough, accelerates very slowly at first, and then more rapidly as detonation approaches. These facts suggest that there are two competing reactions. One is the usual explosive goes to products with the release of energy, and the other is explosive goes to dead explosive with no chemical change and no energy release. The first reaction rate is very sensitive to the local state, and the second is only weakly so. At low pressure very little energy is released and the change to dead explosive dominates. At high pressure, quite the other way, most of the explosive goes to products. Numerous experiments in both the initiation and the full detonation regimes are discussed and compared in testing these ideas.

Davis, William C [Los Alamos National Laboratory

2010-01-01

243

Discriminating between explosions and earthquakes  

NASA Astrophysics Data System (ADS)

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

Cho, Kwang-Hyun

2014-12-01

244

Detection of explosives in soils  

DOEpatents

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

Chambers, William B. (Edgewood, NM); Rodacy, Philip J. (Albuquerque, NM); Phelan, James M. (Bosque Farms, NM); Woodfin, Ronald L. (Sandia Park, NM)

2002-01-01

245

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

SciTech Connect

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

Martineau, R.L.; Prime, M.B.; Anderson, C.A. [Los Alamos National Lab., NM (United States); Smith, F.W. [Colorado State Univ., Fort Collins, CO (United States)

1999-04-01

246

Donor free radical explosive composition  

DOEpatents

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.

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

1980-04-01

247

High Explosive Radio Telemetry System  

SciTech Connect

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

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

1998-11-04

248

Detecting plastics in seedcotton  

Technology Transfer Automated Retrieval System (TEKTRAN)

To increase global market share and value the US cotton industry needs to supply cotton lint that is free of contamination. Removing plastic contamination first requires developing a means to detect plastics in seedcotton. This study was conducted to validate a custom Ion Mobility Spectrometer (IM...

249

Plasticity in fretting contact  

Microsoft Academic Search

The fretting problem of a cyclically loaded cylinder on a flat elastic–plastic surface is analyzed under the assumption of plane strain. Severe fretting conditions are modeled by applying a constant normal load and a cyclic tangential load to the cylinder and describing the contact behavior using a Coulomb friction law. Detailed numerical results are presented for the evolution of plastic

J. M. Ambrico; M. R. Begley

2000-01-01

250

Explosive Microsphere Particle Standards for Trace Explosive Detection Instruments  

NASA Astrophysics Data System (ADS)

Increases in Homeland Security measures have led to a substantial deployment of trace explosive detection systems within the United States and US embassies around the world. One such system is a walk-through portal which aerodynamically screens people for trace explosive particles. Another system is a benchtop instrument that can detect explosives from swipes used to collect explosive particles from surfaces of luggage and clothing. The National Institute of Standards and Technology is involved in a chemical metrology program to support the operational deployment and effective utilization of trace explosive and narcotic detection devices and is working to develop a measurement infrastructure to optimize, calibrate and standardize these instruments. Well characterized test materials are essential for validating the performance of these systems. Particle size, chemical composition, and detector response are particularly important. Here, we describe one method for producing monodisperse polymer microspheres encapsulating trace explosives, simulants, and narcotics using a sonicated co-flow Berkland nozzle. The nozzle creates uniform droplets that undergo an oil/water emulsion process and cure to form hardened microspheres containing the desired analyte. Issues such as particle size, particle uniformity and levels of analyte composition will be discussed.

Staymates, Matthew; Fletcher, Robert; Gillen, Greg

2007-11-01

251

Explosive actuated valve  

DOEpatents

1. A device of the character described comprising the combination of a housing having an elongate bore and including a shoulder extending inwardly into said bore, a single elongate movable plunger disposed in said bore including an outwardly extending flange adjacent one end thereof overlying said shoulder, normally open conduit means having an inlet and an outlet perpendicularly piercing said housing intermediate said shoulder and said flange and including an intermediate portion intersecting and normally openly communicating with said bore at said shoulder, normally closed conduit means piercing said housing and intersecting said bore at a location spaced from said normally open conduit means, said elongate plunger including a shearing edge adjacent the other end thereof normally disposed intermediate both of said conduit means and overlying a portion of said normally closed conduit means, a deformable member carried by said plunger intermediate said flange and said shoulder and normally spaced from and overlying the intermediate portion of said normally open conduit means, and means on the housing communicating with the bore to retain an explosive actuator for moving said plunger to force the deformable member against the shoulder and extrude a portion of the deformable member out of said bore into portions of the normally open conduit means for plugging the same and to effect the opening of said normally closed conduit means by the plunger shearing edge substantially concomitantly with the plugging of the normally open conduit means.

Byrne, Kenneth G. (Livermore, CA)

1983-01-01

252

Explosive plane-wave lens  

DOEpatents

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

Marsh, S.P.

1987-03-12

253

Explosive Spot Joining of Metals  

NASA Technical Reports Server (NTRS)

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

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

1997-01-01

254

Explosives characterization in terahertz range  

NASA Astrophysics Data System (ADS)

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

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

2011-11-01

255

Explosive plane-wave lens  

DOEpatents

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

Marsh, S.P.

1988-03-08

256

JiTT - Cambrian Explosion  

NSDL National Science Digital Library

1) How do scientists come up with the number 2 billion years ago for the first branch of life? Explain the dating technique and information that is used. 2) Describe the evidence AGAINST the Cambrian Explosion. ...

Guertin, Laura

257

Detection of residues from explosive manipulation by near infrared hyperspectral imaging: a promising forensic tool.  

PubMed

In this study near infrared hyperspectral imaging (NIR-HSI) is used to provide a fast, non-contact, non-invasive and non-destructive method for the analysis of explosive residues on human handprints. Volunteers manipulated individually each of these explosives and after deposited their handprints on plastic sheets. For this purpose, classical explosives, potentially used as part of improvised explosive devices (IEDs) as ammonium nitrate, blackpowder, single- and double-base smokeless gunpowders and dynamite were studied. A partial-least squares discriminant analysis (PLS-DA) model was built to detect and classify the presence of explosive residues in handprints. High levels of sensitivity and specificity for the PLS-DA classification model created to identify ammonium nitrate, blackpowder, single- and double-base smokeless gunpowders and dynamite residues were obtained, allowing the development of a preliminary library and facilitating the direct and in situ detection of explosives by NIR-HSI. Consequently, this technique is showed as a promising forensic tool for the detection of explosive residues and other related samples. PMID:25086347

Fernández de la Ossa, Ma Ángeles; Amigo, José Manuel; García-Ruiz, Carmen

2014-09-01

258

Thermodynamic States in Explosion Fields  

Microsoft Academic Search

Here we investigate the thermodynamic states occurring in explosion fields from the detonation of condensed explosives in air. In typical applications, the pressure of expanded detonation products gases is modeled by a Jones-Wilkins-Lee (JWL) function: P{sub JWL} = f(v,s{sub CJ}); constants in that function are fit to cylinder test data. This function provides a specification of pressure as a function

Kuhl

2009-01-01

259

Explosive-powder compaction system  

Microsoft Academic Search

Sandia National Laboratories has developed a pressure-control system and a test fixture to study the behavior of explosive materials during compaction. Both the pressure-control system and the test fixture are self-contained and portable. Explosive materials are compacted in a bridged header charge holder assembly by means of a test fixture and a pneumatic cylinder arrangement. Forces are measured with load

A. P. Montoya; M. L. Reichenbach

1981-01-01

260

On coupling factors of explosion  

NASA Astrophysics Data System (ADS)

The question of the seismic effect of an explosion plays an important part in the theory and practice of demolition engineering, antiseismic engineering, nuclear explosion engineering, seismic exploration, and seismic depth sounding. A still unresolved issue in this regard is concerned with the calculation of energy conversion process. An attempt is made to explore this issue by drawing on the research done in the field of seismic depth sounding.

Shao-Quan, Z.

1985-04-01

261

The characterization and evaluation of accidental explosions  

NASA Technical Reports Server (NTRS)

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

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

1975-01-01

262

Quantitative understanding of explosive stimulus transfer  

NASA Technical Reports Server (NTRS)

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

Schimmel, M. L.

1973-01-01

263

77 FR 54930 - Carlyle Plastics and Resins, Formerly Known as Fortis Plastics, A Subsidiary of Plastics...  

Federal Register 2010, 2011, 2012, 2013

...DEPARTMENT OF LABOR Employment and Training Administration [TA-W-81,655] Carlyle Plastics and Resins, Formerly Known as Fortis Plastics, A Subsidiary of Plastics Acquisitions Inc., Including On-Site Leased Workers From Kelly Services...

2012-09-06

264

PLASTICIZER MOLECULAR WEIGHT AND PLASTICIZER RETENTION IN PVC GEOMEMBRANES  

Microsoft Academic Search

Plasticizers are used to make PVC flexible so it can be used as a geomembrane for containment purposes. Plasticizers can migrate from PVC geomembranes over time because of contact with air, liquid, and an absorbent solid material. Plasticizer migration can reduce the flexibility of PVC geomembranes resulting in brittle behaviour. This paper discusses the three mechanisms of plasticizer migration and

Timothy D. Stark; Patrick W. Diebel

265

Scientific Aspects of Plasticizer Migration from Plasticized Pvc Into Liquids  

Microsoft Academic Search

The polyvinyl chloride (PVC) industry plays an important role in the total plastics industry of today. In most plastics producing countries, PVC is the leading plastic material; in others, for instance the United States and Japan, it is second only to polyethylene. The greater part of PVC is used as soft and plasticized PVC, and PVC applications consume approximately 80%

Jean-Maurice Vergnaud

1983-01-01

266

Plastics Resource: Information on Plastics and the Environment  

NSDL National Science Digital Library

The American Plastics Council (APC) maintains the Plastics Resource: Information on Plastics and the Environment Web site. The APC, which is a major trade association for the US plastics industry, works to promote the benefits of plastics and the plastics industry. Visitors to the site can learn the development history of plastics and how they contribute to our health and safety in the Plastics 101 link. They can also find out how plastics are actually environmentally friendly, how much they really contribute to landfills, how plastic can protect the groundwater, and much more. Although the site is well designed and enjoyable to explore, readers should understand the likely biases associated with organization presenting the information.

267

A Plastic Menagerie  

ERIC Educational Resources Information Center

Bobble heads had become quite popular, depicting all sorts of sports figures, animals, and even presidents. In this article, the author describes how her fourth graders made bobble head sculptures out of empty plastic drink bottles. (Contains 1 online resource.)

Hadley, Mary Jane

2010-01-01

268

Introduction to Plastics  

NSDL National Science Digital Library

Teachers' Domain presents this video as part of a series on advanced technological education. This video illustrates the basics of the plastics industry. The clip teaches the physical properties of plastics, including examples of common plastics. It also includes an animation depicting how monomers join to form polymers, which plastics are made up of. The video goes on to show how polymers and resins are produced. The video may be viewed online or downloaded. To download the clip, users must create a free login for Teachers' Domain. Running time for this QuickTime video is 2:36. Educators will also find a background essay, discussion questions, and standards alignment for the material.

269

Biomechanics Phenotypic plasticity in  

E-print Network

Biomechanics Phenotypic plasticity in juvenile jellyfish medusae facilitates effective animal and altered functionality. Previous studies have indicated that Scyphozoan jellyfish ontogeny accommo- dates; ontogeny; jellyfish 1. INTRODUCTION The swimming and feeding performance of marine ani- mals depends

Dabiri, John O.

270

Plastic Race Car Competition  

NSDL National Science Digital Library

High school students learn about plastics technologies as they design and build car bodies for a remote-control race car competition in this video segment adapted from Pennsylvania College of Technology and WVIA.

2010-07-02

271

Careers in Plastics  

NSDL National Science Digital Library

Learn about opportunities for working in the growing field of plastics, including the emerging area of green technologies, in this video segment adapted from Pennsylvania College of Technology and WVIA.

2010-07-02

272

Breccias related to explosive volcanism  

NASA Astrophysics Data System (ADS)

Explosive breccia pipes were formed in the phreatomagmatic eruption of Taal volcano 60 km south of Manila, Philippines in September 1976. They were photographed in eruption which consisted of a series of small explosions occurring during the peak of activity at 10 sec intervals. These four breccia pipes formed on the collapse fault marking the margin of the much more intense eruption of 28 September 1965 when a diatreme 800 m in diameter formed. Renewed eruption in October 1977 on one of the breccia pipes blasted out the sealed plug and breccia fragments in all stages of alteration were included in the tephra. They ranged from barely agglomerated to strongly cemented through argillized and pyritized to totally replaced by silica and pyrite, fragments indistinguishable from those found in many mining districts. The violence of the explosion initiating a phreatomagmatic eruptive sequence results in strong crackling of the walls of the pipe and the crakle zone may become mineralized (cf. Braden, Chile). Usually the crater collapses on ring faults after eruption, forming a marginal tectonic breccia which can be mineralized (cf. Balatoc, Philippines.) The small craters with steep inner walls and tapering outer slopes which form during phreatomagmatic eruptions, sometimes containing lakes, are called maars and they are the surficial expression of an explosive breccia pipe or diatreme. Superficially similar craters are formed over kimberlite pipes. Hydrothermal explosion craters are somewhat similar. Collapse breccia pipes can form in the same sequence with explosive pipes. When one rising plug encounters ground water and explodes, fluostatic pressure on any other cupolas rising from the same magma drops rapidly, resulting in withdrawal of magma and collapse of walls and roof (Perry 1961). "Fluidization" is not thought to be of any significance in formation of breccia pipes (Wolfe 1980) contrary to Reynolds (1954) and many authors who have cited that work. An explosive breccia pipe is like an open window resulting in rapid depression of the isotherms of a pluton. A concentrated brine front can build up in minutes after an explosion. The very rapid cooling may explain why many explosive breccia pipes are altered by silica and pyrite only, the system being cooled before metallic solutions have time to replace breccia matrix or fragments.

Wolfe, John A.

273

The Need for Plastics Education.  

ERIC Educational Resources Information Center

In view of a lack of trained personnel in the industry, the Plastics Education Foundation proposes that educators (1) add more plastics programs, (2) establish plastics engineering degrees at appropriate 4-year institutions, (3) add plastics processing technology to current engineering curricula, and (4) interest younger students in courses and/or…

Society of Plastics Engineers, Inc., Stamford, CT.

274

PLASTICIZER RETENTION IN PVC GEOMEMBRANES  

Microsoft Academic Search

Plasticizers are used to make PVC flexible so it can be used as a geomembrane for containment purposes. Plasticizers can migrate from PVC geomembranes over time because of contact with air, liquid, and an absorbent solid material. Plasticizer migration can reduce the flexibility of PVC geomembranes. This paper discusses the three mechanisms of plasticizer migration and the factors influencing these

T. D. Stark; H. Choi; P. W. Diebel

275

Thermodynamic States in Explosion Fields  

SciTech Connect

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

Kuhl, A L

2009-10-16

276

Prompt Reaction of Aluminum in Detonating Explosives  

NASA Astrophysics Data System (ADS)

The potential of aluminum reaction to boost detonation energy has been studied for decades, most recently spurred by the availability of nanometer-sized particles. A review of the literature provides perspective for a recent study with the small-scale shock reactivity test. In this test, <1/2-g samples in confinement are shock loaded on one end, and the output at the other end dents a soft witness block. One test series had 0.3 g of HMX mixed with various forms of aluminum added in amounts of up to 25% of the total sample mass, with the deepest dent for H-5 aluminum occuring at 15%. Test results on ammonium perchlorate mixed with H-5 aluminum were consistent with the peak in detonation velocity reported in Combustion and Flame by Price in 1973 on similar mixtures. One outcome of this study is a new interpretation for the participation of aluminum in large scale gap tests on plastic-bonded explosives, which was discussed by Bernecker at this meeting in 1987.

Sandusky, Harold

2005-07-01

277

Insensitive fuze train for high explosives  

DOEpatents

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

Cutting, Jack L. (Livermore, CA); Lee, Ronald S. (Livermore, CA); Von Holle, William G. (Livermore, CA)

1994-01-01

278

Insensitive fuze train for high explosives  

SciTech Connect

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

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

1994-01-04

279

Possibility of compaction of explosion-produced high-velocity metal elements moving in a magnetic field  

Microsoft Academic Search

The accumulation of microdamage due to intense plastic deformation results in a decrease in the average density of high-velocity elements formed by explosive compression of shaped metal liners. For compaction of such elements in tests of the reliability of meteoroid protection, it is suggested that the elements be exposed to a magnetic field produced on their motion trajectory before interaction

S. V. Fedorov

2005-01-01

280

Optimal dynamic detection of explosives  

SciTech Connect

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

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

2009-01-01

281

Evidence for Nearby Supernova Explosions  

E-print Network

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

Narciso Benitez; Jesus Maiz-Apellaniz; Matilde Canelles

2002-01-02

282

The vapor pressures of explosives  

SciTech Connect

The vapor pressures of many explosive compounds are extremely low and thus determining accurate values proves difficult. Many researchers, using a variety of methods, have measured and reported the vapor pressures of explosives compounds at single temperatures, or as a function of temperature using vapor pressure equations. There are large variations in reported vapor pressures for many of these compounds, and some errors exist within individual papers. This article provides a review of explosive vapor pressures and describes the methods used to determine them. We have compiled primary vapor pressure relationships traceable to the original citations and include the temperature ranges for which they have been determined. Corrected values are reported as needed and described in the text. In addition, after critically examining the available data, we calculate and tabulate vapor pressures at 25 °C.

Ewing, Robert G.; Waltman, Melanie J.; Atkinson, David A.; Grate, Jay W.; Hotchkiss, Peter

2013-01-05

283

Saccharification of explosively dried corn  

SciTech Connect

Very rapid or explosive drying of grains such as corn leads to obvious physical changes in the macrostructure of the grain kernel, probable alteration in starch molecular structure, and reduction in starch average molecular weight. These changes lead to greater susceptibility to attack by liquefying and saccharifying enzymes. Rates of formation of nonreducing and reducing sugars by liquefying and saccharifying enzymes applied to explosively dried and milled yellow dent corn and small-kernel flint corn were 3.3-10.6 times greater then rates for the normally milled grains. The enzymatic conversion of explosively dried flint corn containing absorbed ethyl alcohol, as would be the case if it had been used as an adsorbent to dewater aqueous ethyl alcohol, was not significantly different from that of ethyl-alcohol-free flint corn. 15 references.

Robertson, G.H.; Zaragosa, E.M.; Pavlath, A.E.

1986-08-01

284

Permeability enhancement using explosive techniques  

SciTech Connect

In situ recovery methods for many of our hydrocarbon and mineral resources depend on the ability to create or enhance permeability in the resource bed to allow uniform and predictable flow. To meet this need, a new branch of geomechanics devoted to computer prediction of explosive rock breakage and permeability enhancement has developed. The computer is used to solve the nonlinear equations of compressible flow, with the explosive behavior and constitutive properties of the medium providing the initial/boundary conditions and material response. Once the resulting computational tool has been verified and calibrated with appropriate large-scale field tests, it can be used to develop and optimize commercially useful explosive techniques for in situ resource recovery.

Adams, T.F.; Schmidt, S.C.; Carter, W.J.

1980-01-01

285

Explosive evaporation in solar flares  

NASA Technical Reports Server (NTRS)

This paper develops a simple analytical model for the phenomenon of 'explosive evaporation' driven by nonthermal electron heating in solar flares. The model relates the electron energy flux and spectrum, plus details of the preflare atmosphere, to the time scale for explosive evaporation to occur, the maximum pressure and temperature to be reached, rough estimates for the UV pulse emission flux and duration, and the evolution of the blueshifted component of the soft X-ray lines. An expression is given for the time scale for buildup to maximum pressures and the onset of rapid motion of the explosively evaporating plasma. This evaporation can excite a rapid response of UV line and continuum emission. The emission lines formed in the plasma approach a given emissivity-weighted blueshift speed.

Fisher, George H.

1987-01-01

286

Some features of the fabrication of multilayer fiber composites by explosive welding  

NASA Technical Reports Server (NTRS)

The fabrication of multilayer fiber composites by explosive welding is characterized by intense plastic deformation of the matrix material as it fills the spaces between fibers and by high velocity of the collision between matrix layers due to acceleration in the channels between fibers. The plastic deformation of the matrix layers and fiber-matrix friction provide mechanical and thermal activation of the contact surfaces, which contributes to the formation of a bond. An important feature of the process is that the fiber-matrix adhesion strength can be varied over a wide range by varying the parameters of impulsive loading.

Kotov, V. A.; Mikhaylov, A. N.; Cabelka, D.

1985-01-01

287

Nonequilibrium detonation of composite explosives  

SciTech Connect

The effect of nonequilibrium diffusional flow on detonation velocities in composite explosives is examined. Detonation conditions are derived for complete equilibrium, temperature and pressure equilibrium, and two forms of pressure equilibrium. Partial equilibria are associated with systems which have not had sufficient time for transport to smooth out the gradients between spatially separate regions. The nonequilibrium detonation conditions are implemented in the CHEQ equation of state code. We show that the detonation velocity decreases as the non-chemical degrees of freedom of the explosive are allowed to equilibrate. It is only when the chemical degrees of freedom are allowed to equilibrate that the detonation velocity increases.

Nichols III, A.L.

1997-07-01

288

Lightning Protection for Explosive Facilities  

SciTech Connect

Lawrence Livermore National Laboratory funds construction of lightning protection systems to protect explosive processing and storage facilities. This paper provides an intuitive understanding of the lighting risks and types of lightning protection available. Managers can use this information to decide if limited funds should be spent constructing a lightning protection system for their own facilities. This paper answers the following questions: (1) Why do you need lightning protection systems? (2) How do lightning protection systems work? and (3) Why are there no documented cases of lightning problems at existing explosive facilities?

Ong, M

2001-12-01

289

Study on the effect of temperature rise on grain refining during fabrication of nanocrystalline copper under explosive loading  

NASA Astrophysics Data System (ADS)

Nanocrystalline (NC) copper was fabricated by severe plastic deformation of coarse-grained copper at a high strain rate under explosive loading. The feasibility of grain refinement under different explosive loading and the influence of overall temperature rise on grain refinement under impact compression were studied in this paper. The calculation model for the macroscopic temperature rise was established according to the adiabatic shock compression theory. The calculation model for coarse-grained copper was established by the Voronoi method and the microscopic temperature rise resulted from severe plastic deformation of grains was calculated by ANSYS/ls-dyna finite element software. The results show that it is feasible to fabricate NC copper by explosively dynamic deformation of coarse-grained copper and the average grain size of the NC copper can be controlled between 200˜400 nm. The whole temperature rise would increase with the increasing explosive thickness. Ammonium nitrate fuel oil explosive was adopted and five different thicknesses of the explosive, which are 20 mm, 25 mm, 30 mm, 35 mm, 45 mm, respectively, with the same diameter using 20 mm to the fly plate were adopted. The maximum macro and micro temperature rise is up to 532.4 K, 143.4 K, respectively, which has no great effect on grain refinement due to the whole temperature rise that is lower than grain growth temperature according to the high pressure melting theory.

Wang, Jinxiang; Yang, Rui; Jiang, Li; Wang, Xiaoxu; Zhou, Nan

2013-11-01

290

TeachingPlastics.org: Your Virtual Plastics Classroom  

NSDL National Science Digital Library

This site, operated by the American Plastics Council, has a huge amount of plastics resources for both teachers and students. The site is divided into two main sections. Hands On Plastics is geared primarily for middle and high school levels, and Hands On Plastics Jr. is better for elementary school. Educators will find many lesson plans and activities to help them introduce various topics, and they can order a free supplement kit with plastic products. Interactive multimedia walk-throughs of the activities show exactly what needs to be done and how to do it. There is also a large hyperlink list with information about many aspects of plastics.

291

78 FR 1143 - Explosive Siting Requirements; Correction  

Federal Register 2010, 2011, 2012, 2013

...operators in site planning for the storage and handling of energetic liquids and explosives. The FAA inadvertently did not correctly...operators in site planning for the storage and handling of energetic liquids and explosives. In the discussion of the...

2013-01-08

292

30 CFR 77.1301 - Explosives; magazines.  

Code of Federal Regulations, 2012 CFR

...containing explosives shall not be stored in magazines on their ends or sides nor stacked more than 6 feet high. (h) Ammonium nitrate-fuel oil blasting agents shall be physically separated from other explosives, safety fuse, or detonating...

2012-07-01

293

30 CFR 77.1301 - Explosives; magazines.  

...containing explosives shall not be stored in magazines on their ends or sides nor stacked more than 6 feet high. (h) Ammonium nitrate-fuel oil blasting agents shall be physically separated from other explosives, safety fuse, or detonating...

2014-07-01

294

30 CFR 77.1301 - Explosives; magazines.  

Code of Federal Regulations, 2011 CFR

...containing explosives shall not be stored in magazines on their ends or sides nor stacked more than 6 feet high. (h) Ammonium nitrate-fuel oil blasting agents shall be physically separated from other explosives, safety fuse, or detonating...

2011-07-01

295

30 CFR 77.1301 - Explosives; magazines.  

Code of Federal Regulations, 2013 CFR

...containing explosives shall not be stored in magazines on their ends or sides nor stacked more than 6 feet high. (h) Ammonium nitrate-fuel oil blasting agents shall be physically separated from other explosives, safety fuse, or detonating...

2013-07-01

296

30 CFR 77.1301 - Explosives; magazines.  

Code of Federal Regulations, 2010 CFR

...containing explosives shall not be stored in magazines on their ends or sides nor stacked more than 6 feet high. (h) Ammonium nitrate-fuel oil blasting agents shall be physically separated from other explosives, safety fuse, or detonating...

2010-07-01

297

14 CFR 420.63 - Explosive siting.  

Code of Federal Regulations, 2010 CFR

...each public area, including the launch site boundary; (2) A listing of the maximum quantities of liquid and solid propellants and other explosives to be located at each explosive hazard facility, including the class and division for...

2010-01-01

298

14 CFR 420.63 - Explosive siting.  

Code of Federal Regulations, 2011 CFR

...each public area, including the launch site boundary; (2) A listing of the maximum quantities of liquid and solid propellants and other explosives to be located at each explosive hazard facility, including the class and division for...

2011-01-01

299

Numerical Simulations of Thermobaric Explosions  

SciTech Connect

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

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

2007-05-04

300

Powerful explosions at Z = 0?  

NASA Astrophysics Data System (ADS)

Metal-free stars are assumed to evolve at constant mass because of the very low stellar winds. This leads to large CO-core mass at the end of the evolution, so primordial stars with an initial mass between 25 and 85 M? are expected to end as direct black holes, the explosion energy being too weak to remove the full envelope. We show that when rotation enters into play, some mass is lost because the stars are prone to reach the critical velocity during the main sequence evolution. Contrary to what happens in the case of very low- but non zero-metallicity stars, the enrichment of the envelope by rotational mixing is very small and the total mass lost remains modest. The compactness of the primordial stars lead to a very inefficient transport of the angular momentum inside the star, so the profile of ?(r) is close to ?r2 = const. As the core contracts, the rotation rate increases, and the star ends its life with a fast spinning core. Such a configuration has been shown to modify substantially the dynamics of the explosion. Where one expected a weak explosion or none at all, rotation might boost the explosion energy and drive a robust supernova. This will have important consequences in the way primordial stars enriched the early Universe.

Ekström, Sylvia; Meynet, Georges; Hirschi, Raphael; Maeder, André

2008-12-01

301

Turbulent Combustion in SDF Explosions  

SciTech Connect

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

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

2009-11-12

302

Soft container for explosive nuts  

NASA Technical Reports Server (NTRS)

Flexible fabric fits over variety of assembly shapes to contain debris produced by detonations or safety tests. Bag material is woven multifilament polyamide or aramid. Belt loops hold bag to clamp. Ring supports explosive nut structure and detonator wires, and after nut is mounted, bag and clamp are slipped over ring and fastened.

Glenn, D. C.; Drummond, W. E.; Miller, G.

1981-01-01

303

Type IA Supernova Explosion Models  

Microsoft Academic Search

Because calibrated light curves of type Ia supernovae have become a major tool to determine the local expansion rate of the universe and also its geometrical structure, considerable attention has been given to models of these events over the past couple of years. There are good reasons to believe that perhaps most type Ia supernovae are the explosions of white

Wolfgang Hillebrandt; Jens C. Niemeyer

2000-01-01

304

Electrical explosion of segmented wires  

Microsoft Academic Search

The phenomena occurring during the electrical explosion of segmented wires are described. It was observed that with a wire of varying thickness, the smaller diameter parts explode first, ejecting metal vapor radially. Breakdown occurs through the vapor, creating current carrying channels which bypass the larger diameter parts of the wire. This may result, in some cases, in the larger diameter

Y. Me-Bar; R. Harel

1996-01-01

305

Modeling Type Ia Supernova Explosions  

NASA Astrophysics Data System (ADS)

Type Ia Supernovae are one class of bright stellar explosions that are distinguished by a lack of hydrogen in the observed spectra. The most widely accepted scenario is a thermonuclear runaway occurring in a C/O white dwarf that has gained mass from a companion star. The details of the explosion mechanism are incompletely understood, and at present there are competing models that differ in the details of the initial conditions and the nature of the thermonuclear burning. I will present an overview of proposed mechanisms for the explosion and describe the requisite physics for each. Many scenarios invoke a deflagration born near the center of the white dwarf, and the subsequent evolution of the fireball sensitively depends on the relative size of the ignition point and its location. I will describe the flame and ash nuclear energetics and demonstrate that for the case of rising bubbles, featured in some explosion scenarios, the bubble evolution depends sensitively on the nuclear physics included in the models.

Calder, Alan

2008-04-01

306

Remote detector of explosive traces  

NASA Astrophysics Data System (ADS)

This paper presents the results of the research of possibility of remote detection of explosive traces using laser fragmentation/laser-induced fluorescence (LF/LIF) approach. Experimental data on the detection of traces of cyclonite in fingerprints at a distance of 4 m are presented.

Bobrovnikov, Sergey M.; Gorlov, Evgeny V.; Zharkov, Viktor I.; Panchenko, Yury N.; Aksenov, Valery A.; Kikhtenko, Andrey V.; Tivileva, Maria I.

2014-11-01

307

Gas Explosion Characterization, Wave Propagation  

E-print Network

of experiments have been performed with blast waves arising from the ignition .if homogeneous and well defined for this is that larger and larger quantities of dangerous materials are produced, transported and consumed ignition. This develop- ment has made it still more urgent to consider explosion loads in the design phase

308

30 CFR 75.1315 - Boreholes for explosives.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Boreholes for explosives. 75.1315 Section 75.1315 ...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1315 Boreholes for explosives. (a) All explosives fired...

2011-07-01

309

30 CFR 57.6305 - Unused explosive material.  

... 2014-07-01 false Unused explosive material. 57.6305 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground § 57.6305 Unused explosive material. Unused explosive...

2014-07-01

310

30 CFR 75.1315 - Boreholes for explosives.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Boreholes for explosives. 75.1315 Section 75.1315 ...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1315 Boreholes for explosives. (a) All explosives fired...

2012-07-01

311

30 CFR 56.6903 - Burning explosive material.  

...2014-07-01 2014-07-01 false Burning explosive material. 56.6903 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6903 Burning explosive material. If explosive material...

2014-07-01

312

30 CFR 57.6903 - Burning explosive material.  

...2014-07-01 false Burning explosive material. 57.6903 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and Underground § 57.6903 Burning explosive material. If explosive...

2014-07-01

313

30 CFR 56.6903 - Burning explosive material.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Burning explosive material. 56.6903 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6903 Burning explosive material. If explosive material...

2012-07-01

314

27 CFR 555.63 - Explosives magazine changes.  

... 2014-04-01 2014-04-01 false Explosives magazine changes. 555.63 Section 555...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Licenses and...

2014-04-01

315

30 CFR 56.6302 - Separation of explosive material.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Separation of explosive material. 56.6302 Section 56.6302...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Use § 56.6302 Separation of explosive material. Explosives and blasting...

2010-07-01

316

27 CFR 555.205 - Movement of explosive materials.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2010-04-01 true Movement of explosive materials. 555.205 Section 555.205...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Storage §...

2011-04-01

317

27 CFR 555.63 - Explosives magazine changes.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2010-04-01 false Explosives magazine changes. 555.63 Section 555...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Licenses and...

2010-04-01

318

30 CFR 75.1315 - Boreholes for explosives.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Boreholes for explosives. 75.1315 Section 75.1315 ...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1315 Boreholes for explosives. (a) All explosives fired...

2010-07-01

319

30 CFR 75.1315 - Boreholes for explosives.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Boreholes for explosives. 75.1315 Section 75.1315 ...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1315 Boreholes for explosives. (a) All explosives fired...

2013-07-01

320

30 CFR 57.6905 - Protection of explosive material.  

...2014-07-01 false Protection of explosive material. 57.6905 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and Underground § 57.6905 Protection of explosive material. (a) Explosive...

2014-07-01

321

30 CFR 56.6302 - Separation of explosive material.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Separation of explosive material. 56.6302 Section 56.6302...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Use § 56.6302 Separation of explosive material. Explosives and blasting...

2011-07-01

322

30 CFR 56.6305 - Unused explosive material.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Unused explosive material. 56.6305 Section 56.6305...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Use § 56.6305 Unused explosive material. Unused explosive material...

2011-07-01

323

30 CFR 57.6905 - Protection of explosive material.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Protection of explosive material. 57.6905 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and Underground § 57.6905 Protection of explosive material. (a) Explosive...

2012-07-01

324

30 CFR 57.6302 - Separation of explosive material.  

...2014-07-01 false Separation of explosive material. 57.6302 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground § 57.6302 Separation of explosive material. Explosives and...

2014-07-01

325

30 CFR 56.6905 - Protection of explosive material.  

...2014-07-01 false Protection of explosive material. 56.6905 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6905 Protection of explosive material. (a) Explosive...

2014-07-01

326

27 CFR 555.205 - Movement of explosive materials.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Movement of explosive materials. 555.205 Section 555.205...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Storage §...

2010-04-01

327

30 CFR 57.6903 - Burning explosive material.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Burning explosive material. 57.6903 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and Underground § 57.6903 Burning explosive material. If explosive...

2012-07-01

328

30 CFR 56.6305 - Unused explosive material.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Unused explosive material. 56.6305 Section 56.6305...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Use § 56.6305 Unused explosive material. Unused explosive material...

2010-07-01

329

29 CFR 1926.903 - Underground transportation of explosives.  

Code of Federal Regulations, 2010 CFR

...false Underground transportation of explosives. 1926.903 Section 1926.903...CONSTRUCTION Blasting and the Use of Explosives § 1926.903 Underground transportation of explosives. (a) All explosives or...

2010-07-01

330

30 CFR 57.6305 - Unused explosive material.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Unused explosive material. 57.6305 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground § 57.6305 Unused explosive material. Unused explosive...

2010-07-01

331

27 CFR 555.109 - Identification of explosive materials.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Identification of explosive materials. 555.109 Section 555.109...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Conduct of...

2010-04-01

332

30 CFR 56.6905 - Protection of explosive material.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Protection of explosive material. 56.6905 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6905 Protection of explosive material. (a) Explosive...

2011-07-01

333

30 CFR 57.6302 - Separation of explosive material.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Separation of explosive material. 57.6302 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground § 57.6302 Separation of explosive material. Explosives and...

2012-07-01

334

30 CFR 56.6905 - Protection of explosive material.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Protection of explosive material. 56.6905 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6905 Protection of explosive material. (a) Explosive...

2012-07-01

335

30 CFR 57.6302 - Separation of explosive material.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Separation of explosive material. 57.6302 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground § 57.6302 Separation of explosive material. Explosives and...

2011-07-01

336

30 CFR 57.6305 - Unused explosive material.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Unused explosive material. 57.6305 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground § 57.6305 Unused explosive material. Unused explosive...

2011-07-01

337

30 CFR 57.6905 - Protection of explosive material.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Protection of explosive material. 57.6905 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and Underground § 57.6905 Protection of explosive material. (a) Explosive...

2010-07-01

338

30 CFR 56.6302 - Separation of explosive material.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Separation of explosive material. 56.6302 Section 56.6302...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Use § 56.6302 Separation of explosive material. Explosives and blasting...

2013-07-01

339

30 CFR 57.6305 - Unused explosive material.  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Unused explosive material. 57.6305 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground § 57.6305 Unused explosive material. Unused explosive...

2012-07-01

340

30 CFR 57.6302 - Separation of explosive material.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Separation of explosive material. 57.6302 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground § 57.6302 Separation of explosive material. Explosives and...

2013-07-01

341

30 CFR 56.6905 - Protection of explosive material.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Protection of explosive material. 56.6905 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6905 Protection of explosive material. (a) Explosive...

2010-07-01

342

30 CFR 56.6905 - Protection of explosive material.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Protection of explosive material. 56.6905 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6905 Protection of explosive material. (a) Explosive...

2013-07-01

343

30 CFR 56.6302 - Separation of explosive material.  

... 2014-07-01 false Separation of explosive material. 56.6302 Section 56.6302...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Use § 56.6302 Separation of explosive material. Explosives and blasting...

2014-07-01

344

30 CFR 57.6903 - Burning explosive material.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Burning explosive material. 57.6903 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and Underground § 57.6903 Burning explosive material. If explosive...

2010-07-01

345

27 CFR 555.63 - Explosives magazine changes.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 2013-04-01 false Explosives magazine changes. 555.63 Section 555...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Licenses and...

2013-04-01

346

30 CFR 57.6905 - Protection of explosive material.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Protection of explosive material. 57.6905 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and Underground § 57.6905 Protection of explosive material. (a) Explosive...

2011-07-01

347

30 CFR 56.6305 - Unused explosive material.  

...2014-07-01 2014-07-01 false Unused explosive material. 56.6305 Section 56.6305...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Use § 56.6305 Unused explosive material. Unused explosive material...

2014-07-01

348

27 CFR 555.109 - Identification of explosive materials.  

Code of Federal Regulations, 2012 CFR

... 2010-04-01 true Identification of explosive materials. 555.109 Section 555.109...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Conduct of...

2012-04-01

349

30 CFR 57.6903 - Burning explosive material.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Burning explosive material. 57.6903 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and Underground § 57.6903 Burning explosive material. If explosive...

2013-07-01

350

29 CFR 1926.903 - Underground transportation of explosives.  

...false Underground transportation of explosives. 1926.903 Section 1926.903...CONSTRUCTION Blasting and the Use of Explosives § 1926.903 Underground transportation of explosives. (a) All explosives or...

2014-07-01

351

30 CFR 56.6305 - Unused explosive material.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Unused explosive material. 56.6305 Section 56.6305...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Use § 56.6305 Unused explosive material. Unused explosive material...

2013-07-01

352

27 CFR 555.63 - Explosives magazine changes.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 2010-04-01 true Explosives magazine changes. 555.63 Section 555...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Licenses and...

2011-04-01

353

30 CFR 75.1315 - Boreholes for explosives.  

...2014-07-01 false Boreholes for explosives. 75.1315 Section 75.1315 ...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1315 Boreholes for explosives. (a) All explosives fired...

2014-07-01

354

30 CFR 56.6302 - Separation of explosive material.  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Separation of explosive material. 56.6302 Section 56.6302...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Use § 56.6302 Separation of explosive material. Explosives and blasting...

2012-07-01

355

30 CFR 57.6903 - Burning explosive material.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Burning explosive material. 57.6903 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and Underground § 57.6903 Burning explosive material. If explosive...

2011-07-01

356

29 CFR 1926.903 - Underground transportation of explosives.  

Code of Federal Regulations, 2012 CFR

...false Underground transportation of explosives. 1926.903 Section 1926.903...CONSTRUCTION Blasting and the Use of Explosives § 1926.903 Underground transportation of explosives. (a) All explosives or...

2012-07-01

357

27 CFR 555.205 - Movement of explosive materials.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Movement of explosive materials. 555.205 Section 555.205...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Storage §...

2013-04-01

358

27 CFR 555.63 - Explosives magazine changes.  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 2010-04-01 true Explosives magazine changes. 555.63 Section 555...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Licenses and...

2012-04-01

359

30 CFR 56.6305 - Unused explosive material.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Unused explosive material. 56.6305 Section 56.6305...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Use § 56.6305 Unused explosive material. Unused explosive material...

2012-07-01

360

30 CFR 56.6903 - Burning explosive material.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Burning explosive material. 56.6903 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6903 Burning explosive material. If explosive material...

2013-07-01

361

29 CFR 1926.903 - Underground transportation of explosives.  

Code of Federal Regulations, 2013 CFR

...false Underground transportation of explosives. 1926.903 Section 1926.903...CONSTRUCTION Blasting and the Use of Explosives § 1926.903 Underground transportation of explosives. (a) All explosives or...

2013-07-01

362

30 CFR 56.6903 - Burning explosive material.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Burning explosive material. 56.6903 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6903 Burning explosive material. If explosive material...

2011-07-01

363

30 CFR 57.6302 - Separation of explosive material.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Separation of explosive material. 57.6302 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground § 57.6302 Separation of explosive material. Explosives and...

2010-07-01

364

27 CFR 555.205 - Movement of explosive materials.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2010-04-01 true Movement of explosive materials. 555.205 Section 555.205...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Storage §...

2012-04-01

365

30 CFR 57.6305 - Unused explosive material.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Unused explosive material. 57.6305 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground § 57.6305 Unused explosive material. Unused explosive...

2013-07-01

366

27 CFR 555.109 - Identification of explosive materials.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Identification of explosive materials. 555.109 Section 555.109...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Conduct of...

2013-04-01

367

30 CFR 57.6905 - Protection of explosive material.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Protection of explosive material. 57.6905 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and Underground § 57.6905 Protection of explosive material. (a) Explosive...

2013-07-01

368

30 CFR 56.6903 - Burning explosive material.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Burning explosive material. 56.6903 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6903 Burning explosive material. If explosive material...

2010-07-01

369

27 CFR 555.205 - Movement of explosive materials.  

...2014-04-01 2014-04-01 false Movement of explosive materials. 555.205 Section 555.205...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Storage §...

2014-04-01

370

29 CFR 1926.903 - Underground transportation of explosives.  

Code of Federal Regulations, 2011 CFR

...false Underground transportation of explosives. 1926.903 Section 1926.903...CONSTRUCTION Blasting and the Use of Explosives § 1926.903 Underground transportation of explosives. (a) All explosives or...

2011-07-01

371

Aspects of dynamic recrystallization in shaped charge and explosively formed projectile devices  

Microsoft Academic Search

Under a shock wave, a shaped charge (SC) liner or an explosively formed projectile (EFP) device transforms into a jet and\\u000a a slug. At various laboratories, it was found that the transformation was closely related to extensive plastic flow occurring\\u000a at high strain rates. Along with the shape trans-formation, there is evidence of changes in hardness, strength, grain configuration,\\u000a microstructure,

C. Feng; L. E. Murr; C.-S. Niou

1996-01-01

372

Curved detonation fronts in solid explosives 1 Curved detonation fronts in solid explosives  

E-print Network

Curved detonation fronts in solid explosives 1 Curved detonation fronts in solid explosives(). At the edges of the explosive, Dn() is supplemented with boundary conditons. By direct numerical simulation for simulating complex explosive-containing systems. Key words: Detonation, Curvature eect, Edge interactions

Aslam, Tariq

373

14 CFR 420.63 - Explosive siting.  

Code of Federal Regulations, 2012 CFR

...A listing of the maximum quantities of liquid and solid propellants and other explosives to be located at each explosive hazard...explosive and the hazard and compatibility group for each liquid propellant; and (3) A description of each activity to be...

2012-01-01

374

`Strangelove ocean' before the Cambrian explosion  

Microsoft Academic Search

The Palaeozoic and Mesozoic eras were terminated by faunal changes involving mass extinction of the old and explosive evolution of the new fauna, but the fossil record shows only a Cambrian Explosion at the end of the Precambrian. Stanley speculated that the explosion was only possible after the ubiquitous algae community had been largely eliminated1; ecological niches were thus liberated

Kenneth J. Hsu; Hedi Oberhänsli; J. Y. Gao; Sun Shu; Chen Haihong; Urs Krähenbühl

1985-01-01

375

Analysis of Picattiny Sample for Trace Explosives  

SciTech Connect

The sample received from Picatinny Arsenal was analyzed for trace amounts of high explosives (HE). A complete wash of the surface was performed, concentrated, and analyzed using two sensitive analysis techniques that are capable of detecting numerous types of explosives. No explosives were detected with either test.

Klunder, G; Whipple, R; Carman, L; Spackman, P E; Reynolds, J; Alcaraz, A

2008-05-23

376

Explosives remain preferred methods for platform abandonment  

Microsoft Academic Search

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

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

1996-01-01

377

Doping explosive materials for neutron radiographic enhancement.  

NASA Technical Reports Server (NTRS)

Discussion of studies relating to the selection of doping materials of high neutron absorption usable for enhancing the neutron radiographic imaging of explosive mixtures, without interfering with the proper chemical reaction of the explosives. The results of the studies show that gadolinium oxide is an excellent material for doping explosive mixtures to enhance the neutron radiographic image.

Golliher, K. G.

1971-01-01

378

Transuranic drum hydrogen explosion tests  

SciTech Connect

Radiolysis of transuranic (TRU) waste can produce flammable ({gt}4%) mixtures of hydrogen gas in 55 gallon vented waste storage drums. Explosion testing was conducted at the E. I. duPont Explosion Hazards Laboratory to determine the minimum concentration at which a drum lid removal occurs. A secondary objective was to investigate the maximum pressure and rate of pressure rise as a function of hydrogen concentration. Prior to beginning any drum explosion tests, small-scale pressure vessel tests and drum mixing tests were completed. The pressure vessel tests established a relationship between hydrogen concentration and the maximum pressure and pressure rise. These small-scale tests were used to establish the concentration range over which a drum lid removal might occur. Mixing tests were also conducted to determine the equilibration times for two different hydrogen-air mixtures in a TRU drum. Nine successful drum explosion tests were conducted over a hydrogen concentration range of 13--36% (v/v), test results suggest total integrity failure via drum lid removal will not occur below 15% (v/v). Controlled small-scale pressure vessel tests were conducted over a range of 5--50% (v/v) to determine the pressure and pressure rise as a function of hydrogen concentration. No similar relationship could be established for the drum explosion tests due to the variability in drum lid sealing and retaining ring closure. Mixing tests conducted at 5% and 25% (v/v) indicate adding pure hydrogen to the middle of a drum causes some initial stratification along the drum length, but the air and hydrogen become well-mixed after 50 minutes. 4 refs., 11 figs., 2 tabs.

Dykes, K.L.; Meyer, M.L.

1991-06-01

379

Fast and sensitive recognition of various explosive compounds using Raman spectroscopy and principal component analysis  

NASA Astrophysics Data System (ADS)

Recently, the development of methods for the identification of explosive materials that are faster, more sensitive, easier to use, and more cost-effective has become a very important issue for homeland security and counter-terrorism applications. However, limited applicability of several analytical methods such as, the incapability of detecting explosives in a sealed container, the limited portability of instruments, and false alarms due to the inherent lack of selectivity, have motivated the increased interest in the application of Raman spectroscopy for the rapid detection and identification of explosive materials. Raman spectroscopy has received a growing interest due to its stand-off capacity, which allows samples to be analyzed at distance from the instrument. In addition, Raman spectroscopy has the capability to detect explosives in sealed containers such as glass or plastic bottles. We report a rapid and sensitive recognition technique for explosive compounds using Raman spectroscopy and principal component analysis (PCA). Seven hundreds of Raman spectra (50 measurements per sample) for 14 selected explosives were collected, and were pretreated with noise suppression and baseline elimination methods. PCA, a well-known multivariate statistical method, was applied for the proper evaluation, feature extraction, and identification of measured spectra. Here, a broad wavenumber range (200- 3500 cm-1) on the collected spectra set was used for the classification of the explosive samples into separate classes. It was found that three principal components achieved 99.3 % classification rates in the sample set. The results show that Raman spectroscopy in combination with PCA is well suited for the identification and differentiation of explosives in the field.

Hwang, Joonki; Park, Aaron; Chung, Jin Hyuk; Choi, Namhyun; Park, Jun-Qyu; Cho, Soo Gyeong; Baek, Sung-June; Choo, Jaebum

2013-06-01

380

Gas chromatography/ion mobility spectrometry as a hyphenated technique for improved explosives detection and analysis  

NASA Technical Reports Server (NTRS)

Ion Mobility Spectrometry (IMS) is currently being successfully applied to the problem of on-line trace detection of plastic and other explosives in airports and other facilities. The methods of sample retrieval primarily consist of batch sampling for particulate residue on a filter card for introduction into the IMS. The sample is desorbed into the IMS using air as the carrier and negative ions of the explosives are detected, some as an adduct with a reagent ion such as Cl(-). Based on studies and tests conducted by different airport authorities, this method seems to work well for low vapor pressure explosives such as RDX and PETN, as well as TNT that are highly adsorptive and can be found in nanogram quantities on contaminated surfaces. Recently, the changing terrorist threat and the adoption of new marking agents for plastic explosives has meant that the sample introduction and analysis capabilities of the IMS must be enhanced in order to keep up with other detector developments. The IMS has sufficient analytical resolution for a few threat compounds but the IMS Plasmogram becomes increasingly more difficult to interpret when the sample mixture gets more complex.

Mercado, AL; Marsden, Paul

1995-01-01

381

2/13/2014 Household explosion replaces population explosion as world concern -UPI.com http://www.upiasia.com/Science-Technology/2014/02/11/Household-explosion-replaces-population-explosion-as-world-concern/UPI-87811392152198/ 1/1  

E-print Network

2/13/2014 Household explosion replaces population explosion as world concern - UPI.com http://www.upiasia.com/Science-Technology/2014/02/11/Household-explosion-replaces-population-explosion-as-world-concern/UPI-87811392152198/ 1 & Technology / Household explosion replaces population explosion as world concern Science & Technology

382

Plastics in Perspective.  

ERIC Educational Resources Information Center

The materials in this curriculum supplement, developed for middle school or high school science classes, present solid waste problems related to plastics. The set of curriculum materials is divided into two units to be used together or independently. Unit I begins by comparing patterns in solid waste from 1960 to 1990 and introducing methods for…

Bergandine, David R.; Holm, D. Andrew

383

STATIC ELECTRICITY Plastic combs  

E-print Network

plates · Plastic lids · Unflavored gelatin powder · Long hair, fleece jacket, wool sweater..... Questions or by having them blow up a balloon and use that instead of the comb. Gelatin Stalactites 1. Pour a little of the gelatin powder on a paper plate. 2. Have the kids blow up their own balloon. 3. Rub the balloon

Benitez-Nelson, Claudia

384

Periodontal Plastic Surgery  

MedlinePLUS

Periodontal plastic surgery is designed to restore form and function to the gum tissue, periodontal ligament, and the bone that supports your teeth ... tooth. The real long-term goal of any periodontal surgery is to increase the life expectancy of ...

385

Stem cell plasticity  

Microsoft Academic Search

The central dogma in stem cell biology has been that cells isolated from a particular tissue can renew and differentiate into lineages of the tissue it resides in. Several studies have challenged this idea by demonstrating that tissue specific cell have considerable plasticity and can cross-lineage restriction boundary and give rise to cell types of other lineages. However, the lack

Uma Lakshmipathy; Catherine Verfaillie

2005-01-01

386

Neural Plasticity in Schizophrenia  

Microsoft Academic Search

No current biological hypothesis can assimilate the genetic, environmental, and clinical features of schizophrenia. If, as some authors contend, environmental factors have important effects on the course of schizophrenia, then a fruitful research concern may be the adaptation of neuronal circuitry to environmental changes. The plasticity of neuronal connections has been studied by subjecting animals to neurosurgical lesions, brain electrostimulation,

John L. Haracz

1985-01-01

387

Plastics (Environmental Health Student Portal)  

MedlinePLUS

... how exposure occurs, and associated health effects. Plastics - Danger Where We Least Expect It? (PDF, 700.14 ... Harvard School of Public Health) - Information on the dangers of plastic: public health threats, regulations, solutions, and ...

388

Spot test kit for explosives detection  

DOEpatents

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.

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

389

Plasticity characteristic obtained by indentation  

Microsoft Academic Search

A dimensionless parameter ?H = ?p\\/?t (where ?p and ?t are the average values of plastic and total deformation of material on the contact area indenter–specimen) may be used as the plasticity characteristic of materials, which made it possible to characterize the plasticity of materials that are brittle in standard mechanical tests. ?H may be calculated from the values of

Yu V Milman

2008-01-01

390

Liquids and homemade explosive detection  

NASA Astrophysics Data System (ADS)

Excerpt from the US Transportation Security Agency website: "The ban on liquids, aerosols and gels was implemented on August 10 after a terrorist plot was foiled. Since then, experts from around the government, including the FBI and our national labs have analyzed the information we now have and have conducted extensive explosives testing to get a better understanding of this specific threat." In order to lift the ban and ease the burden on the flying public, Reveal began an extensive effort in close collaboration with the US and several other governments to help identify these threats. This effort resulted in the successful development and testing of an automated explosive detection system capable of resolving these threats with a high probability of detection and a low false alarm rate. We will present here some of the methodology and approach we took to address this problem.

Ellenbogen, Michael; Bijjani, Richard

2009-05-01

391

Medical imaging of explosion injuries.  

PubMed

Diagnosing and caring for injuries caused by explosives were once almost exclusively the province of combat medical personnel, but with the increase in foreign and domestic terrorism, civilians have become targets. Blasts create complicated medical pictures and paint a wide swath of injuries. Medical responders and hospitals must focus on planning for mass casualty incidents. Medical imaging personnel can learn from worldwide efforts to diagnose and treat blast-related injuries and apply these lessons to the potential for domestic terrorism and to caring for victims of accidental explosions. They also can better understand long-term effects on military and civilian personnel who have been exposed to blast injuries on foreign soil. PMID:20207791

Church, Elizabeth J

2010-01-01

392

Explosives detection system and method  

DOEpatents

A method of detecting explosives in a vehicle includes providing a first rack on one side of the vehicle, the rack including a neutron generator and a plurality of gamma ray detectors; providing a second rack on another side of the vehicle, the second rack including a neutron generator and a plurality of gamma ray detectors; providing a control system, remote from the first and second racks, coupled to the neutron generators and gamma ray detectors; using the control system, causing the neutron generators to generate neutrons; and performing gamma ray spectroscopy on spectra read by the gamma ray detectors to look for a signature indicative of presence of an explosive. Various apparatus and other methods are also provided.

Reber, Edward L. (Idaho Falls, ID); Jewell, James K. (Idaho Falls, ID); Rohde, Kenneth W. (Idaho Falls, ID); Seabury, Edward H. (Idaho Falls, ID); Blackwood, Larry G. (Idaho Falls, ID); Edwards, Andrew J. (Idaho Falls, ID); Derr, Kurt W. (Idaho Falls, ID)

2007-12-11

393

Applying NASA's explosive seam welding  

NASA Technical Reports Server (NTRS)

The status of an explosive seam welding process, which was developed and evaluated for a wide range of metal joining opportunities, is summarized. The process employs very small quantities of explosive in a ribbon configuration to accelerate a long-length, narrow area of sheet stock into a high-velocity, angular impact against a second sheet. At impact, the oxide films of both surface are broken up and ejected by the closing angle to allow atoms to bond through the sharing of valence electrons. This cold-working process produces joints having parent metal properties, allowing a variety of joints to be fabricated that achieve full strength of the metals employed. Successful joining was accomplished in all aluminum alloys, a wide variety of iron and steel alloys, copper, brass, titanium, tantalum, zirconium, niobium, telerium, and columbium. Safety issues were addressed and are as manageable as many currently accepted joining processes.

Bement, Laurence J.

1991-01-01

394

Printable sensors for explosive detonation  

NASA Astrophysics Data System (ADS)

Here, we report the development of an organic thin film transistor (OTFT) based on printable solution processed polymers and employing a quantum tunnelling composite material as a sensor to convert the pressure wave output from detonation transmission tubing (shock tube) into an inherently amplified electronic signal for explosives initiation. The organic electronic detector allows detection of the signal in a low voltage operating range, an essential feature for sites employing live ordinances that is not provided by conventional electronic devices. We show that a 30-fold change in detector response is possible using the presented detector assembly. Degradation of the OTFT response with both time and repeated voltage scans was characterised, and device lifetime is shown to be consistent with the requirements for on-site printing and usage. The integration of a low cost organic electronic detector with inexpensive shock tube transmission fuse presents attractive avenues for the development of cheap and simple assemblies for precisely timed initiation of explosive chains.

Griffith, Matthew J.; Cooling, Nathan A.; Elkington, Daniel C.; Muller, Elmar; Belcher, Warwick J.; Dastoor, Paul C.

2014-10-01

395

Combustion effects in confined explosions  

Microsoft Academic Search

Results of shock-dispersed-fuel (SDF) explosion experiments are presented. The SDF charge consisted of a spherical 0.5-g PETN booster surrounded by 1g of fuel, either flake aluminum (Al) powder or TNT. The charge was placed at the center of a sealed chamber. Three cylindrical chambers (volumes of 6.6, 20, and 40l with L\\/D=1) and three tunnels (L\\/D=3.8, 4.65, and 12.5) were

A. L. Kuhl; H. Reichenbach

2009-01-01

396

Electromagnetic Effects in SDF Explosions  

Microsoft Academic Search

The notion of high ion and electron concentrations in the detonation of aluminized explosive mixtures has aroused some interest in electro-magnetic effects that the SDF charges might generate when detonated. Motivated by this interest we have started to investigate whether significant electro-magnetic effects show up in our small-scale experiments. However, the design of instrumentation for this purpose is far from

H Reichenbach; P Neuwald; A L Kuhl

2010-01-01

397

Thermodynamic States in Explosion Fields  

SciTech Connect

We investigate the thermodynamic states occurring in explosion fields from condensed explosive charges. These states are often modeled with a Jones-Wilkins-Lee (JWL) function. However, the JWL function is not a Fundamental Equation of Thermodynamics, and therefore cannot give a complete specification of such states. We use the Cheetah code of Fried to study the loci of states of the expanded detonation products gases from C-4 charges, and their combustion products air. In the Le Chatelier Plane of specific-internal-energy versus temperature, these loci are fit with a Quadratic Model function u(T), which has been shown to be valid for T < 3,000 K and p < 1k-bar. This model is used to derive a Fundamental Equation u(v,s) for C-4. Given u(v,s), one can use Maxwell's Relations to derive all other thermodynamic functions, such as temperature: T(v,s), pressure: p(v,s), enthalpy: h(v,s), Gibbs free energy: g(v,s) and Helmholz free energy: f(v,s); these loci are displayed in figures for C-4. Such complete equations of state are needed for numerical simulations of blast waves from explosive charges, and their reflections from surfaces.

Kuhl, A L

2010-03-12

398

The Arson & Explosives National Repository  

NSDL National Science Digital Library

The Arson & Explosives National Repository, hosted by the US Bureau of Alcohol, Tobacco, and Firearms(ATF), currently includes three database systems, providing statistics gathered by the ATF, the US Federal Bureau of Investigation (FBI), and the US Fire Administration (USFA). The first database, the Explosives Incident System (EXIS), contains several data tables that detail the arson and explosives incidents reported to the ATF from 1975 to 1995. The second database, the USFA's National Fire Incident Reporting System (NFIRS), provides the "world's largest national annual database of fire incident information." NFIRS offers annual data tables for a range of fire incidents from 1981 to 1995. The third database in the repository, Church Arson Task Force Data, presents data on church arsons and bombings from 1995 to 1997; data are displayed in tables, charts, and graphs. Besides providing a list of available data, each system allows users to conduct customizable queries. Within each system, users may search for incident data within a specified date range, or produce a five-year incident summary for any state in the US.

399

Adipose tissue plasticity from WAT to BAT and in between.  

PubMed

Adipose tissue plays an essential role in regulating energy balance through its metabolic, cellular and endocrine functions. Adipose tissue has been historically classified into anabolic white adipose tissue and catabolic brown adipose tissue. An explosion of new data, however, points to the remarkable heterogeneity among the cells types that can become adipocytes, as well as the inherent metabolic plasticity of mature cells. These data indicate that targeting cellular and metabolic plasticity of adipose tissue might provide new avenues for treatment of obesity-related diseases. This review will discuss the developmental origins of adipose tissue, the cellular complexity of adipose tissues, and the identification of progenitors that contribute to adipogenesis throughout development. We will touch upon the pathological remodeling of adipose tissue and discuss how our understanding of adipose tissue remodeling can uncover new therapeutic targets. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease. PMID:23688783

Lee, Yun-Hee; Mottillo, Emilio P; Granneman, James G

2014-03-01

400

Stress-gradient plasticity.  

PubMed

A new model, stress-gradient plasticity, is presented that provides unique mechanistic insight into size-dependent phenomena in plasticity. This dislocation-based model predicts strengthening of materials when a gradient in stress acts over dislocation source-obstacle configurations. The model has a physical length scale, the spacing of dislocation obstacles, and is validated by several levels of discrete-dislocation simulations. When incorporated into a continuum viscoplastic model, predictions for bending and torsion in polycrystalline metals show excellent agreement with experiments in the initial strengthening and subsequent hardening as a function of both sample-size dependence and grain size, when the operative obstacle spacing is proportional to the grain size. PMID:21911403

Chakravarthy, Srinath S; Curtin, W A

2011-09-20

401

Stress-gradient plasticity  

PubMed Central

A new model, stress-gradient plasticity, is presented that provides unique mechanistic insight into size-dependent phenomena in plasticity. This dislocation-based model predicts strengthening of materials when a gradient in stress acts over dislocation source–obstacle configurations. The model has a physical length scale, the spacing of dislocation obstacles, and is validated by several levels of discrete-dislocation simulations. When incorporated into a continuum viscoplastic model, predictions for bending and torsion in polycrystalline metals show excellent agreement with experiments in the initial strengthening and subsequent hardening as a function of both sample-size dependence and grain size, when the operative obstacle spacing is proportional to the grain size. PMID:21911403

Chakravarthy, Srinath S.; Curtin, W. A.

2011-01-01

402

Data base of chemical explosions in Kazakhstan  

SciTech Connect

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

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

1996-12-01

403

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

NASA Technical Reports Server (NTRS)

A method and associated apparatus for confining the undesirable by-products and limiting noise of explosive welding are discussed. The apparatus consists fo a simple enclosure into which the explosive is placed and within which the explosion occurs. The shape of the enclosure, the placement of the explosive, and the manner in which the enclosure is placed upon the material to be welded determine the force of the explosion transmitted to the proposed bond area. The explosion is totally confined within the enclosure thus reducing the noise level and preventing debris from being strewn about to contaminate the weld area or create personnel hazards.

Bement, L. J. (inventor)

1974-01-01

404

Hydrodynamics of explosion: models and software for modeling explosions and estimation of their consequences  

NASA Astrophysics Data System (ADS)

Physical and hydrodynamic processes accompanying explosions of condensed explosives and fuel-air mixtures have been considered. Wide-range equations of state of explosion products and air have been used. A physical model and a program code based on the gas dynamics equations in the Lagrangian form have been developed for modeling one-dimensional hydrodynamic processes in the near zone of explosion. This firmware forms the basis for estimation of explosion consequences. The described model has shown its working efficiency within a wide range of explosion energies and environmental conditions.

Stepanov, K. L.; Stankevich, Y. A.; Smetannikov, A. S.

2012-11-01

405

Cutting the plastic  

Microsoft Academic Search

Students from The University of Notre Dame Australia recently turned Coles Supermarket Fremantle into their “laboratory” for a week, in an attempt to encourage shoppers to abandon plastic shopping bags in favour of the environmentally-friendly alternatives.\\u000aThrough collaboration between the University, City of Fremantle and Coles; Notre Dame environmental education students are getting the chance to learn about some of

Michelle Ebbs

2005-01-01

406

Compensatory plasticity: time matters  

PubMed Central

Plasticity in the human and animal brain is the rule, the base for development, and the way to deal effectively with the environment for making the most efficient use of all the senses. When the brain is deprived of one sensory modality, plasticity becomes compensatory: the exception that invalidates the general loss hypothesis giving the opportunity of effective change. Sensory deprivation comes with massive alterations in brain structure and function, behavioral outcomes, and neural interactions. Blind individuals do as good as the sighted and even more, show superior abilities in auditory, tactile and olfactory processing. This behavioral enhancement is accompanied with changes in occipital cortex function, where visual areas at different levels become responsive to non-visual information. The intact senses are in general used more efficiently in the blind but are also used more exclusively. New findings are disentangling these two aspects of compensatory plasticity. What is due to visual deprivation and what is dependent on the extended use of spared modalities? The latter seems to contribute highly to compensatory changes in the congenitally blind. Short-term deprivation through the use of blindfolds shows that cortical excitability of the visual cortex is likely to show rapid modulatory changes after few minutes of light deprivation and therefore changes are possible in adulthood. However, reorganization remains more pronounced in the congenitally blind. Cortico-cortical pathways between visual areas and the areas of preserved sensory modalities are inhibited in the presence of vision, but are unmasked after loss of vision or blindfolding as a mechanism likely to drive cross-modal information to the deafferented visual cortex. The development of specialized higher order visual pathways independently from early sensory experience is likely to preserve their function and switch to the intact modalities. Plasticity in the blind is also accompanied with neurochemical and morphological changes; both intrinsic connectivity and functional coupling at rest are altered but are likewise dependent on different sensory experience and training. PMID:24971056

Lazzouni, Latifa; Lepore, Franco

2014-01-01

407

Plastic footwear for leprosy.  

PubMed

The anaesthetic foot in leprosy poses the most major problem in the rehabilitation of its patients. Various attempts have been made to produce protective footwear such as the microcellular rubber-car-tyre sandals. Unfortunately these attempts have had little success on a large scale because of the inability to produce them in large numbers and the stigma attached to such unusual footwear. While such footwear may be superior to the 'tennis' shoe in protecting the foot from injury by the penetration of sharp objects, it fails to distribute the weight-bearing forces which is the major cause of plantar damage and ulceration in the anaesthetic foot. This can be achieved by providing rigidity to the sole, as demonstrated by the healing of ulcers in plaster of paris casts or the rigid wooden clog. A new type of moulded plastic footwear has been evolved in conjunction with the plastic footwear industry which provides footwear that can be mass produced at a low price and which overcomes the stigma of leprosy. Controlled rigidity is provided by the incorporation of a spring steel shank between the sponge insole and the hard wearing plastic sole. Trials have demonstrated both the acceptability of the footwear and its protective effects as well as its hard wearing properties. PMID:2319903

Antia, N H

1990-03-01

408

Plastics eLearning  

NSDL National Science Digital Library

The Plastics Resources for Educators Program (PREP) has developed a broad range of multimedia instructional resources on synthesis, structure, properties, applications and processing of plastics. The interactive programs and virtual instruments create an exploratory learning environment that allows students to explore complex multivariable problems. This project is to develop a sustainable dissemination effort that includes workshops for faculty and the construction of workbooks and CDROMs that customize the use of various modules to address educational needs of different audiences. Dissemination is done through a commercial publisher, but marketing is done through faculty contacts, industrial partners, a special interest group associated with the Society of Plastics Engineers and presentations at professional meetings. A PREP web site is a communications and distribution hub. Formative and summative evaluation of all components is done by a third party evaluator. The interactive electronic materials provide faculty with new ways of teaching. MERC Online reviewer comments: Innovative simulations allow students to virtually operate equipment. Animations show crow sections of processes. Free, easily downloadable animations, images, and simulations.

409

Respiratory muscle plasticity.  

PubMed

Muscle plasticity is defined as the ability of a given muscle to alter its structural and functional properties in accordance with the environmental conditions imposed on it. As such, respiratory muscle is in a constant state of remodeling, and the basis of muscle's plasticity is its ability to change protein expression and resultant protein balance in response to varying environmental conditions. Here, we will describe the changes of respiratory muscle imposed by extrinsic changes in mechanical load, activity, and innervation. Although there is a large body of literature on the structural and functional plasticity of respiratory muscles, we are only beginning to understand the molecular-scale protein changes that contribute to protein balance. We will give an overview of key mechanisms regulating protein synthesis and protein degradation, as well as the complex interactions between them. We suggest future application of a systems biology approach that would develop a mathematical model of protein balance and greatly improve treatments in a variety of clinical settings related to maintaining both muscle mass and optimal contractile function of respiratory muscles. PMID:23798306

Gransee, Heather M; Mantilla, Carlos B; Sieck, Gary C

2012-04-01

410

Microelectronics plastic molded packaging  

SciTech Connect

The use of commercial off-the-shelf (COTS) microelectronics for nuclear weapon applications will soon be reality rather than hearsay. The use of COTS for new technologies for uniquely military applications is being driven by the so-called Perry Initiative that requires the U.S. Department of Defense (DoD) to accept and utilize commercial standards for procurement of military systems. Based on this philosophy, coupled with several practical considerations, new weapons systems as well as future upgrades will contain plastic encapsulated microelectronics. However, a conservative Department of Energy (DOE) approach requires lifetime predictive models. Thus, the focus of the current project is on accelerated testing to advance current aging models as well as on the development of the methodology to be used during WR qualification of plastic encapsulated microelectronics. An additional focal point involves achieving awareness of commercial capabilities, materials, and processes. One of the major outcomes of the project has been the definition of proper techniques for handling and evaluation of modern surface mount parts which might be used in future systems. This program is also raising the familiarity level of plastic within the weapons complex, allowing subsystem design rules accommodating COTS to evolve. A two year program plan is presented along with test results and commercial interactions during this first year.

Johnson, D.R. [Ktech Corp., Albuquerque, NM (United States); Palmer, D.W.; Peterson, D.W. [Sandia National Lab., Albuquerque, NM (United States)] [and others

1997-02-01

411

Plasticity of loudness perception  

NASA Astrophysics Data System (ADS)

Evidence from the management of tinnitus and hyperacusis suggests that loudness perception is plastic and adaptable. We have undertaken a study to evaluate this idea. The motivation followed from clinical observations suggesting that the magnitude of perceived loudness and, in turn, the rate of loudness growth can be manipulated either upward or downward by prolonged reduction or enhancement in the level of background sound to which a listener is exposed. Accordingly, volunteers were fitted bilaterally with in-the-ear noise instruments (NI treatment) or sound-attenuating earplugs (EP treatment). Both treatments produced audibility threshold shifts, mainly above 1000 Hz. The effects of each treatment were evaluated after 2 weeks of continuous use relative to pretreatment loudness response data obtained using the Contour Test of loudness perception. The resulting loudness data for warble tones revealed opposite patterns of plasticity for the two treatments, with steeper and shallower (than pretreatment) loudness growth functions measured, respectively, for the EP and NI treatments. These effects were significantly different for loudness response categories judged to be comfortably loud or louder at both 500 and 2000 Hz. Possible mechanisms for this apparent plasticity of loudness will be discussed. [Research supported by NIDCD.

Formby, Craig; Sherlock, Laguinn P.; Gold, Susan L.

2002-05-01

412

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

SciTech Connect

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

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

1998-03-01

413

Explosives Detection: Exploitation of the Physical Signatures  

NASA Astrophysics Data System (ADS)

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

Atkinson, David

2010-10-01

414

Explosive Vapor Detection Using Microcantilever Sensors  

SciTech Connect

Explosive-based terrorism is an eminent threat to a civilized and free society. Accurate and cost-effective explosive sensors are, therefore, essential for combating the terrorist threat. Some of the main performance characteristics for explosive sensors include sensitivity, selectivity, and real-time fast operation. As the vapor pressures of commonly used explosives are extremely small, highly sensitive sensors are essential for detecting trace quantities of explosives. Moreover, the sensors should have high selectivity to have an acceptable rate of false positives. Also, these sensors should have the capability of mass deployment because of the breadth of terrorist threats involving explosives [1]. Finally, these sensors should have fast detection and regeneration time for fast operation. Currently available sensors are unable to satisfy these requirements.

Senesac, Larry R [ORNL; Thundat, Thomas George [ORNL

2007-01-01

415

Eigenvalue Detonation of Combined Effects Aluminized Explosives  

NASA Astrophysics Data System (ADS)

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

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

2007-06-01

416

Instrumentation advances in emissions characterization from propellant/explosive combustion  

SciTech Connect

Results from a chamber study to characterize emissions from combustion of selected pure energetic materials are presented in this paper. The study was carried out as a part of a comprehensive air pathways risk assessment for a propellant and explosive manufacturing facility that engages in open burning methods for manufacturing waste disposal. Materials selected for emissions characterization in this study included both aluminized and non-aluminized composite propellant, a double base propellant and a plastic bonded explosive. Combustion tests in a specialized chamber revealed very low emissions for gaseous products of incomplete combustion such as carbon monoxide and nitrogen oxides. Analysis of gaseous and aerosol emission products for a pre-selected target analyte list that included both volatile and semi-volatile organics revealed either low or non-detectable emissions for the four energetic types tested. Hydrogen chloride was detected as a major emission product from propellants containing ammonium perchlorate. Results from this work reveal that about one-half of the chlorine in the original material is released as hydrogen chloride. Based on earlier work, the balance of the chlorine emissions is expected to be in the form of chlorine gas.

Einfeld, W.; Morrison, D.J. [Sandia National Labs., Albuquerque, NM (United States); Mullins, S.E. [Alliant Techsystems, Inc., Rocket Center, WV (United States)

1995-12-31

417

Inhibitory Plasticity Dictates the Sign of Plasticity at Excitatory Synapses  

PubMed Central

The broad connectivity of inhibitory interneurons and the capacity of inhibitory synapses to be plastic make them ideal regulators of the level of excitability of many neurons simultaneously. Whether inhibitory synaptic plasticity may also contribute to the selective regulation of single neurons and local microcircuits activity has not been investigated. Here we demonstrate that in rat primary visual cortex inhibitory synaptic plasticity is connection specific and depends on the activation of postsynaptic GABAB–Gi/o protein signaling. Through the activation of this intracellular signaling pathway, inhibitory plasticity can alter the state of a single postsynaptic neuron and directly affect the induction of plasticity at its glutamatergic inputs. This interaction is modulated by sensory experience. Our data demonstrate that in recurrent circuits, excitatory and inhibitory forms of synaptic plasticity are not integrated as independent events, but interact to cooperatively drive the activity-dependent rewiring of local microcircuits. PMID:24453301

Wang, Lang

2014-01-01

418

Wireless sensor for detecting explosive material  

DOEpatents

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.

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

2014-10-28

419

Air Activation Following an Atmospheric Explosion  

SciTech Connect

In addition to thermal radiation and fission products, nuclear explosions result in a very high flux of unfissioned neutrons. Within an atmospheric nuclear explosion, these neutrons can activate the various elemental components of natural air, potentially adding to the radioactive signature of the event as a whole. The goal of this work is to make an order-of-magnitude estimate of the total amount of air activation products that can result from an atmospheric nuclear explosion.

Lowrey, Justin D.; McIntyre, Justin I.; Prichard, Andrew W.; Gesh, Christopher J.

2013-03-13

420

An analysis of spectral differences between Nevada Test Site and Shagan River nuclear explosions  

NASA Astrophysics Data System (ADS)

Spectral ratio discrimination studies carried out on events located in the western United States and Soviet Union (S.U.) illustrate that pronounced differences in radiated explosion-source spectra relative to nearby earthquakes exist between the two regions. Nevada Test Site (NTS) explosions are characterized by the existence of more low-frequency and/or less high-frequency energy (greater low-to high-frequency spectral ratios) than western U.S. earthquakes. The opposite pattern is observed in the S.U. with nuclear explosions appearing to have more high-frequency (and/or less low-frequency) energy than earthquakes. These observations may be caused by at least two principal effects that are probably acting in parallel: (1) variations in depth-dependent effects of attenuation acting between the shallow explosions and deeper earthquakes and (2) differences in the dynamic response of the near-source geology to the passing explosion shock wave. Anelastic synthetic seismogram calculations illustrate that depth-dependent attenuation effects may explain the spectral observations. However, a number of observations using near- and far-field data from NTS explosions suggest that near-source effects are the dominant factor. A quasi-empirical explosion source model is proposed that simultaneously fits the spectral ratio data from both the U.S. and S.U. relative to earthquakes in each of the respective regions. Additionally, the model fits the trends of the spectral ratios observed as a function of magnitude. The key to the model is the shape of the pressure time history acting at the elastic radius. For explosions detonated in weak, porous rock, the radiated shock wave divides into a two-wave system consisting of an elastic precursor followed by a plastic wave. The generation of this two-wave system introduces a rise time into the pressure time history. In the frequency domain a second corner frequency is established in a third-order model (with an ?-3 high-frequency decay) whose value is inversely proportional to the time separation of the two waves. In higher-strength, saturated rocks (or for overburied explosions) the effective rise time is short, and a second-order model is appropriate (with an ?-2 high-frequency decay). The second-order model provides a good fit to the S.U. data. In contrast, a hybrid model is required to fit the NTS data with an ?-3 high-frequency decay for shallow explosions detonated in unsaturated tuff that evolves to an ?-2 decay as depth of burials reach higher-strength, saturated rocks below the water table.

Taylor, Steven R.; Denny, Marvin D.

1991-04-01

421

Evaluation of surface storage facilities for explosives, blasting agents and other explosive materials  

NASA Astrophysics Data System (ADS)

The histories of recent and past magazine explosions were reviewed; present explosive storage conditions and practices were observed; and existing Federal regulations on explosive storage were examined. A recent increase in magazine explosion frequency must be attributed to a large increase in deliberate explosions; fires of various origins account for the remaining explosions of the past decade. During 1884-1926 several lightning generated explosions occurred in nonmetal magazines. It appears that the contents of a well constructed metal magazine are immune to direct lightning strikes, regardless of whether the magazine is grounded or not. Grounding a metal magazine cannot be harmful, but it maywell be superfluous. Mine Safety and Health Administration and Bureau of Alcohol, Tobacco and Firearms standards on explosive storage appear to cover safety aspects adequately. Certain revisions are recommended to clarify some of the standards and to reduce inconsistencies in their enforcement.

Roth, J.

1983-06-01

422

Shock Initiation of Damaged Explosives  

SciTech Connect

Explosive and propellant charges are subjected to various mechanical and thermal insults that can increase their sensitivity over the course of their lifetimes. To quantify this effect, shock initiation experiments were performed on mechanically and thermally damaged LX-04 (85% HMX, 15% Viton by weight) and PBX 9502 (95% TATB, 5% Kel-F by weight) to obtain in-situ manganin pressure gauge data and run distances to detonation at various shock pressures. We report the behavior of the HMX-based explosive LX-04 that was damaged mechanically by applying a compressive load of 600 psi for 20,000 cycles, thus creating many small narrow cracks, or by cutting wedge shaped parts that were then loosely reassembled, thus creating a few large cracks. The thermally damaged LX-04 charges were heated to 190 C for long enough for the beta to delta solid - solid phase transition to occur, and then cooled to ambient temperature. Mechanically damaged LX-04 exhibited only slightly increased shock sensitivity, while thermally damaged LX-04 was much more shock sensitive. Similarly, the insensitive explosive PBX 9502 was mechanically damaged using the same two techniques. Since PBX 9502 does not undergo a solid - solid phase transition but does undergo irreversible or 'rachet' growth when thermally cycled, thermal damage to PBX 9502 was induced by this procedure. As for LX-04, the thermally damaged PBX 9502 demonstrated a greater shock sensitivity than mechanically damaged PBX 9502. The Ignition and Growth reactive flow model calculated the increased sensitivities by igniting more damaged LX-04 and PBX 9502 near the shock front based on the measured densities (porosities) of the damaged charges.

Chidester, S K; Vandersall, K S; Tarver, C M

2009-10-22

423

Explosion Welding for Hermetic Containerization  

NASA Technical Reports Server (NTRS)

A container designed for storing samples of hazardous material features a double wall, part of which is sacrificed during an explosion-welding process in which the container is sealed and transferred to a clean environment. The major advantage of this container sealing process is that once the samples have been sealed inside, the outer wall of what remains of the container is a clean surface that has not come into contact with the environment from which the samples were taken. Thus, there is no need to devise a decontamination process capable of mitigating all hazards that might be posed by unanticipated radioactive, chemical, and/or biological contamination of the outside of the container. The container sealing method was originally intended to be used to return samples from Mars to Earth, but it could also be used to store samples of hazardous materials, without the need to decontaminate its outer surface. The process stages are shown. In its initial double-wall form, the volume between the walls is isolated from the environment; in other words, the outer wall (which is later sacrificed) initially serves to protect the inner container from contamination. The sample is placed inside the container through an opening at one end, then the container is placed into a transfer dock/lid. The surfaces that will be welded together under the explosive have been coated with a soft metallic sacrificial layer. During the explosion, the sacrificial layer is ejected, and the container walls are welded together, creating a strong metallic seal. The inner container is released during the same event and enters the clean environment.

Dolgin, Benjamin; Sanok, Joseph

2003-01-01

424

Use of recycled plastics in wood plastic composites - a review.  

PubMed

The use of recycled and waste thermoplastics has been recently considered for producing wood plastic composites (WPCs). They have great potential for WPCs manufacturing according to results of some limited researches. This paper presents a detailed review about some essential properties of waste and recycled plastics, important for WPCs production, and of research published on the effect of recycled plastics on the physical and mechanical properties of WPCs. PMID:23777666

Kazemi Najafi, Saeed

2013-09-01

425

Explosions  

MedlinePLUS

... about your plan. Make plans for your pets Bomb Threats If you receive a telephoned bomb threat, you should do the following: Get as ... to ask the following questions: When is the bomb going to explode? Where is it right now? ...

426

Big Explosions and Strong Gravity  

NSDL National Science Digital Library

This guide has been developed to assist people who would like to run the Big Explosions and Strong Gravity event with their local Girl Scout Council. The event is a one-day event in which a group of Girl Scouts spends their time doing a series of hands-on activities on spectroscopy, cosmic abundances, supernovae, and black holes. Professional scientists, engineers, and graduate students assist with these activities, giving the scouts a chance to interact with professionals in science and technology fields.

2011-01-01

427

Explosive demolition of activated concrete  

NASA Astrophysics Data System (ADS)

This paper describes the removal of a radiologically contaminated concrete pad. This pad was removed during 1979 by operating personnel under the direction of the Waste Management Program of EG and G Idaho, Inc. The concrete pad was the foundation for the Organic Moderated Reactor Experiment (OMRE) reactor vessel. The pad consisted of a cylindrical concrete slab 15 ft in diameter, 2 ft thick, and reinforced with steel bar. It was poured directly onto basalt rocks approximately 20 ft below grade. The entire pad contained induced radioactivity and was therefore demolished, boxed, and buried rather than being decontaminated. The pad was demolished by explosive blasting.

Smith, D. L.

1980-04-01

428

Supernova Explosions Stay In Shape  

NASA Astrophysics Data System (ADS)

At a very early age, children learn how to classify objects according to their shape. Now, new research suggests studying the shape of the aftermath of supernovas may allow astronomers to do the same. A new study of images from NASA's Chandra X-ray Observatory on supernova remnants - the debris from exploded stars - shows that the symmetry of the remnants, or lack thereof, reveals how the star exploded. This is an important discovery because it shows that the remnants retain information about how the star exploded even though hundreds or thousands of years have passed. "It's almost like the supernova remnants have a 'memory' of the original explosion," said Laura Lopez of the University of California at Santa Cruz, who led the study. "This is the first time anyone has systematically compared the shape of these remnants in X-rays in this way." Astronomers sort supernovas into several categories, or "types", based on properties observed days after the explosion and which reflect very different physical mechanisms that cause stars to explode. But, since observed remnants of supernovas are leftover from explosions that occurred long ago, other methods are needed to accurately classify the original supernovas. Lopez and colleagues focused on the relatively young supernova remnants that exhibited strong X-ray emission from silicon ejected by the explosion so as to rule out the effects of interstellar matter surrounding the explosion. Their analysis showed that the X-ray images of the ejecta can be used to identify the way the star exploded. The team studied 17 supernova remnants both in the Milky Way galaxy and a neighboring galaxy, the Large Magellanic Cloud. For each of these remnants there is independent information about the type of supernova involved, based not on the shape of the remnant but, for example, on the elements observed in it. The researchers found that one type of supernova explosion - the so-called Type Ia - left behind relatively symmetric, circular remnants. This type of supernova is thought to be caused by a thermonuclear explosion of a white dwarf, and is often used by astronomers as "standard candles" for measuring cosmic distances. On the other hand, the remnants tied to the "core-collapse" supernova explosions were distinctly more asymmetric. This type of supernova occurs when a very massive, young star collapses onto itself and then explodes. "If we can link supernova remnants with the type of explosion", said co-author Enrico Ramirez-Ruiz, also of University of California, Santa Cruz, "then we can use that information in theoretical models to really help us nail down the details of how the supernovas went off." Models of core-collapse supernovas must include a way to reproduce the asymmetries measured in this work and models of Type Ia supernovas must produce the symmetric, circular remnants that have been observed. Out of the 17 supernova remnants sampled, ten were classified as the core-collapse variety, while the remaining seven of them were classified as Type Ia. One of these, a remnant known as SNR 0548-70.4, was a bit of an "oddball". This one was considered a Type Ia based on its chemical abundances, but Lopez finds it has the asymmetry of a core-collapse remnant. "We do have one mysterious object, but we think that is probably a Type Ia with an unusual orientation to our line of sight," said Lopez. "But we'll definitely be looking at that one again." While the supernova remnants in the Lopez sample were taken from the Milky Way and its close neighbor, it is possible this technique could be extended to remnants at even greater distances. For example, large, bright supernova remnants in the galaxy M33 could be included in future studies to determine the types of supernova that generated them. The paper describing these results appeared in the November 20 issue of The Astrophysical Journal Letters. NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA's Scie

2009-12-01

429

Method and apparatus for detecting explosives  

DOEpatents

A method and apparatus is provided for detecting explosives by thermal imaging. The explosive material is subjected to a high energy wave which can be either a sound wave or an electromagnetic wave which will initiate a chemical reaction in the explosive material which chemical reaction will produce heat. The heat is then sensed by a thermal imaging device which will provide a signal to a computing device which will alert a user of the apparatus to the possibility of an explosive device being present.

Moore, David Steven (Santa Fe, NM)

2011-05-10

430

Detecting explosive substances by the IR spectrography  

NASA Astrophysics Data System (ADS)

Fast and safe detection methods of explosive substances are needed both before and after actualized explosions. This article presents an experiment of the detection of three selected explosives by the ATR FTIR spectrometer and by three different IR hyperspectral imaging devices. The IR spectrometers give accurate analyzing results, whereas hyperspectral imagers can detect and analyze desired samples without touching the unidentified target at all. In the controlled explosion experiment TNT, dynamite and PENO were at first analyzed as pure substances with the ATR FTIR spectrometer and with VNIR, SWIR and MWIR cameras. After three controlled explosions also the residues of TNT, dynamite and PENO were analyzed with the same IR devices. The experiments were performed in arctic outdoor conditions and the residues were collected on ten different surfaces. In the measurements the spectra of all three explosives were received as pure substances with all four IR devices. Also the explosion residues of TNT were found on cotton with the IR spectrometer and with VNIR, SWIR and MWIR hyperspectral imagers. All measurements were made directly on the test materials which had been placed on the explosion site and were collected for the analysis after each blast. Measurements were made with the IR spectrometer also on diluted sample. Although further tests are suggested, the results indicate that the IR spectrography is a potential detection method for explosive subjects, both as pure substances and as post-blast residues.

Kuula, J.; Rinta, Heikki J.; Pölönen, I.; Puupponen, H.-H.; Haukkamäki, Marko; Teräväinen, T.

2014-05-01

431

Flixborough revisited - an explosion simulation approach.  

PubMed

A literature study of explosion estimation reports from the Flixborough accident was performed and commented. The results from this survey were compared to the results obtained from explosion simulations. The simulations were done with a computer model of the Flixborough plant using the EXSIM software simulation tool. The comparison showed that explosion magnitude estimates in the literature based on visual inspection are much lower than the simulated results, while the estimates based on calculations to a large degree conform with the simulations. The simulations also showed that the exact location of the ignition source does not seem to be significant for the magnitude of the explosion. PMID:10946115

Høiset, S; Hjertager, B H; Solberg, T; Malo, K A

2000-10-01

432

The explosion problem in a flow  

E-print Network

We consider the explosion problem in an incompressible flow introduced in the paper of H. Berestycki, L. Kagan, G. Joulin and G. Sivashinsky. We use a novel $L^p-L^\\infty$ estimate for elliptic advection-diffusion problems to show that the explosion threshold obeys a positive lower bound which is uniform in the advecting flow. We also identify the flows for which the explosion threshold tends to infinity as their amplitude grows and obtain an effective description of the explosion threshold in the strong flow asymptotics in a two-dimensional one-cell flow.

Henri Berestycki; Alexander Kiselev; Alexei Novikov; Lenya Ryzhik

2009-07-29

433

27 CFR 555.26 - Prohibited shipment, transportation, receipt, possession, or distribution of explosive materials.  

Code of Federal Regulations, 2012 CFR

...receipt, possession, or distribution of explosive materials. 555.26 Section 555.26...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES...

2012-04-01

434

27 CFR 555.26 - Prohibited shipment, transportation, receipt, possession, or distribution of explosive materials.  

Code of Federal Regulations, 2013 CFR

...receipt, possession, or distribution of explosive materials. 555.26 Section 555.26...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES...

2013-04-01

435

27 CFR 555.26 - Prohibited shipment, transportation, receipt, possession, or distribution of explosive materials.  

...receipt, possession, or distribution of explosive materials. 555.26 Section 555.26...BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES...

2014-04-01

436

Metal objects mapping after small charge explosions. A study on AISI 304Cu steel with two different grain sizes.  

PubMed

Evidence of exposure of a metal component to a small charge explosion can be detected by observing microstructural modifications; they may be present even if the piece does not show noticeable overall plastic deformations. Particularly, if an austenitic stainless steel (or another metal having a face-centered cubic structure and a low stacking fault energy) is exposed to an explosive shock wave, high-speed deformation induces primarily mechanical twinning, whereas, in nonexplosive events, a lower velocity plastic deformation first induces slip. The occurrence of mechanical twins can be detected even if the surface is damaged or oxidized in successive events. In the present research, optical metallography (OM) and scanning electron microscopy (SEM), and scanning tunneling microscopy (STM) were used to detect microstructural modifications caused on AISI 304Cu steel disks by small-charge explosions. Spherical charges of 54.5 or 109 g TNT equivalent mass were used at explosive-to-target distances from 6.5 to 81.5 cm, achieving peak pressures from 160 to 0.5 MPa. Explosions induced limited or no macro-deformation. Two alloy grain sizes were tested. Surface OM and SEM evidenced partial surface melting, zones with recrystallization phenomena, and intense mechanical twinning, which was also detected by STM and X-ray diffraction. In the samples' interior, only twins were seen, up to some distance from the explosion impinged surface and again, at the shortest charge-to-sample distances, in a thin layer around the reflecting surface. For forensic science locating purposes after explosions, the maximum charge-to-target distance at which the phenomena disappear was singled out for each charge or grain size and related to the critical resolved shear stress for twinning. PMID:16696699

Firrao, Donato; Matteis, Paolo; Scavino, Giorgio; Ubertalli, Graziano; Ienco, Maria G; Pellati, Gabriella; Piccardo, Paolo; Pinasco, Maria R; Stagno, Enrica; Costanza, Girolamo; Montanari, Roberto; Tata, Maria E; Brandimarte, Giovanni; Petralia, Santo

2006-05-01

437

Fabrication of plastic biochips  

SciTech Connect

A versatile surface functionalization procedure based on rf magnetron sputtering of silica was performed on poly(methylmethacrylate), polycarbonate, polypropylene, and cyclic olefin copolymers (Topas 6015). The hybrid thermoplastic surfaces were characterized by x-ray photoelectron spectrometer analysis and contact angle measurements. The authors then used these hybrid materials to perform a sandwich assay targeting an HIV-1 antibody using fluorescent detection and biotinylated peptides immobilized using the bioaffinity of biotin-neutravidin. They found a limit of detection similar to arrays on glass surfaces and believed that this plastic biochip platform may be used for the development of disposable immunosensing and diagnostic applications.

Saaem, Ishtiaq; Ma, Kuo-Sheng; Alam, S. Munir; Tian Jingdong [Department of Biomedical Engineering and Institute for Genome Sciences and Policy, Duke University, Durham, North Carolina 27708 (United States); Department of Medicine and Human Vaccine Institute, Duke University, Durham, North Carolina 27708 (United States); Department of Biomedical Engineering and Institute for Genome Sciences and Policy, Duke University, Durham, North Carolina 27708 (United States)

2010-07-15

438

Psychotherapy and brain plasticity  

PubMed Central

In this paper, I will review why psychotherapy is relevant to the question of how consciousness relates to brain plasticity. A great deal of the research and theorizing on consciousness and the brain, including my own on hallucinations for example (Collerton and Perry, 2011) has focused upon specific changes in conscious content which can be related to temporal changes in restricted brain systems. I will argue that psychotherapy, in contrast, allows only a focus on holistic aspects of consciousness; an emphasis which may usefully complement what can be learnt from more specific methodologies. PMID:24046752

Collerton, Daniel

2013-01-01

439

[Update: blast and explosion trauma].  

PubMed

In recent decades, acoustic shock and explosion traumas have increased in frequency in the general population. Beside the use of fireworks and firearms, airbag ignitions and explosions caused by terror or suicidal acts are also relevant. Depending on duration and strength of the sound pressure affecting the human ear, isolated inner ear damage or additional ear drum perforation and interruption of the middle ear ossicle chain can result. By means of otoscopy, pure tone audiometry, measurement of otoacoustic emissions, and other neurootological examinations, the severity of the trauma can be determined. With prompt and adequate therapy, permanent hearing loss can be minimized. In particular, the measurement of otoacoustic emissions allows conclusions to be made on the functionality of the outer hair cells which are damaged first in most cases. Histological investigations on noise-exposed cochleas show extensive damage to the outer hair cells in the frequency range between 1.0 and 4.0 kHz, which correlates well with audiometric measurements. PMID:21769579

van de Weyer, P S; Praetorius, M; Tisch, M

2011-08-01

440

Explosive double salts and preparation  

DOEpatents

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.

Cady, Howard H. (Los Alamos, NM); Lee, Kien-yin (Los Alamos, NM)

1984-01-01

441

Immobile plasticizer in flexible PVC  

Microsoft Academic Search

Plasticized poly(vinyl chloride) (PVC) is one of the most widely used polymeric materials in medical and related applications, and usually contains up to 40 per cent di-(2-ethylhexyl)phthalate (DEHP), which acts as the `plasticizer' to impart flexibility to an otherwise rigid PVC. The plasticizer can migrate from PVC-based devices and storage bags into physiological fluids, however, and has been detected in

A. Jayakrishnan; S. Lakshmi

1998-01-01

442

Plastic plants and patchy soils  

Microsoft Academic Search

Soil nutrients are distributed in a non-uniform or 'patchy' manner. It is well established that the modular nature of root systems allows them to show both morphological and\\/or physiological plasticity upon encountering nutrient-rich patches. These plastic re- sponses are widely believed to be foraging mech- anisms by the plant to enhance nutrient resource capture. Although morphological plasticity has trad- itionally

A. Hodge

2010-01-01

443

Cosmic Explosions in Three Dimensions  

NASA Astrophysics Data System (ADS)

Introduction: 3-D Explosions: a meditation on rotation (and magnetic fields) J. C. Wheeler; Part I. Supernovae: Observations Today: 1. Supernova explosions: lessons from spectropolarimetry L. Wang; 2. Spectropolarimetric observations of Supernovae A. Filippenko and D. C. Leonard; 3. Observed and physical properties of type II plateau supernovae M. Hamuy; 4. SN1997B and the different types of Type Ic Supernovae A. Clocchiatti, B. Leibundgut, J. Spyromilio, S. Benetti, E. Cappelaro, M. Turatto and M. Phillips; 5. Near-infrared spectroscopy of stripped-envelope Supernovae C. L. Gerardy, R. A. Fesen, G. H. Marion, P. Hoeflich and J. C. Wheeler; 6. Morphology of Supernovae remnants R. Fesen; 7. The evolution of Supernova remnants in the winds of massive stars V. Dwarkadas; 8. Types for the galactic Supernovae B. E. Schaefer; Part II. Theory of Thermonuclear Supernovae: 9. Semi-steady burning evolutionary sequences for CAL 83 and CAL 87: supersoft X-ray binaries are Supernovae Ia progenitors S. Starrfield, F. X. Timmes, W. R. Hix, E. M. Sion, W. M. Sparks and S. Dwyer; 10. Type Ia Supernovae progenitors: effects of the spin-up of the white dwarfs S.-C. Yoon and N. Langer; 11. Terrestrial combustion: feedback to the stars E. S. Oran; 12. Non-spherical delayed detonations E. Livne; 13. Numerical simulations of Type Ia Supernovae: deflagrations and detonations V. N. Gamezo, A. M. Khokhlov and E. S. Oran; 14. Type Ia Supernovae: spectroscopic surprises D. Branch; 15. Aspherity effects in Supernovae P. Hoeflich, C. Gerardy and R. Quimby; 16. Broad light curve SneIa: asphericity or something else? A. Howell and P. Nugent; 17. Synthetic spectrum methods for 3-D SN models R. Thomas; 18. A hole in Ia' spectroscopic and polarimetric signatures of SN Ia asymmetry due to a companion star D. Kasen; 19. Hunting for the signatures of 3-D explosions with 1-D synthetic spectra E. Lentz, E. Baron and P. H. Hauschildt; 20. On the variation of the peak luminosity of Type Ia J. W. Truran, E. X. Timmes and E. F. Brown; Part III. Theory of Core Collapse Supernovae: 21. Rotation of core collapse progenitors: single and binary stars N. Langer; 22. Large scale convection and the convective Supernova mechanism S. Colgate and M. E. Herant; 23. Topics in core-collapse Supernova A. Burrows, C. D. Ott and C. Meakin; 24. MHD Supernova jets: the missing link D. Meier and M. Nakamura; 25. Effects of super strong magnetic fields in core collapse Supernovae I. S. Akiyama; 26. Non radial instability of stalled accretion shocks advective-acoustic cycle T. Foglizzo and P. Galletti; 27. Asymmetry effects in Hypernovae K. Maeda, K. Nomoto, J. Deng and P.A. Mazzali; 28. Turbulent MHD jet collimation and thermal driving P. T. Williams; Part IV. Magnetars, N-Stars, Pulsars: 29. Supernova remnants and pulsar wind nebulae R. Chevalier; 30. X-Ray signatures of Supernovae D. Swartz; 31. Asymmetric Supernovae and Neutron Star Kicks D. Lai and D. Q. Lamb; 32. Triggers of magnetar outbursts R. Duncan; 33. Turbulent MHD Jet Collimation and Thermal Driving P. Williams; 34. The interplay between nuclear electron capture and fluid dynamics in core collapse Supernovae W. R. Hix, O. E. B. Messer and A. Mezzacappa; Part V. Gamma-Ray Bursts: 35. GRB 021004 and Gamma-ray burst distances B. E. Schaefer; 36. Gamma-ray bursts as a laboratory for the study of Type Ic Supernovae D. Q. Lamb, T. Q. Donaghy and C. Graziani; 37. The diversity of cosmic explosions: Gamma-ray bursts and Type Ib/c Supernovae E. Berger; 38. A GRB simulation using 3D relativistic hydrodynamics J. Cannizo, N. Gehrels and E. T. Vishniac; 39. The first direct link in the Supernova/GRB connection: GRB 030329 and SN 2003dh T. Matheson; Part VI. Summary: 40. Three-dimensional explosions C. Wheeler.

Höflich, Peter; Kumar, Pawan; Wheeler, J. Craig

2004-12-01

444

Pre-explosive conduit conditions of the 1997 Vulcanian explosions at Soufrire Hills Volcano, Montserrat: I. Pressure and vesicularity distributions.  

E-print Network

Pre-explosive conduit conditions of the 1997 Vulcanian explosions at Soufrière Hills Volcano of Vulcanian eruptive dynamics is the series of 88 explosions that occurred between August and October 1997 explosion is still poorly understood, but conditions the eruptive style. This study establishes such a pre-explosive

Boyer, Edmond

445

Optimizing plastic parts for recycling  

SciTech Connect

This article describes how proven guidelines allow engineers to consider recycling from the beginning of the design process. Applications of automotive plastics to reach specific design targets date back many years, with both weight of plastics used and share of plastics in vehicle weight increasing constantly. The amount of plastics used in the automobile will continue to increase in the future, because of more demanding design concepts, new safety requirements, customer demand for increased comfort, reduced production costs, and general demand for reduced fuel consumption.

NONE

1996-05-01

446

Time-domain terahertz spectroscopy and applications on drugs and explosives  

NASA Astrophysics Data System (ADS)

Many materials of interest to the forensic and security services, such as explosives, drugs and biological agents, exhibit characteristic spectral features in the terahertz (THz) frequency range. These spectral features originate from inter-molecular interactions, involving collective motions of molecules. Broadband THz time-domain spectroscopy (THz-TDS) system have been used to analyze a number of drugs-of-abuse and explosives that are of interest to the forensic and security services. These samples ranged from crystalline powders, pressed into pellets, to thin sheets of plastic explosives, and all being measured in transmission geometry in the frequency range 0.1 - 8 THz. To well understand the nature of the observed spectral features and the effects of thermal broadening on these far-infrared signatures, temperature-dependent THz-TDS measurements have also been performed at temperatures as low as 4 K, especially for two types of cocaine. Well-resolved low-frequency absorption peaks were observed in the frequency range 0.1 - 3 THz with high resolution. Some of absorption peaks were found clearly to become more intense and shift to higher frequencies as the temperature was reduced. The results confirm that the low-frequency collective modes are highly sensitive to the structural and spatial arrangement of molecules. Furthermore, a number of common postal packaging materials made from paper, cardboard, even several types of plastic, have been tested with drug sample to assess the ability of THz-TDS in a hostile detection environment.

Fan, W. H.; Zhao, W.; Cheng, G. H.; Burnett, A. D.; Upadhya, P. C.; Cunningham, J. E.; Linfield, E. H.; Davies, A. G.

2008-03-01

447

Optogenetics and synaptic plasticity  

PubMed Central

The intricate and complex interaction between different populations of neurons in the brain has imposed limits on our ability to gain detailed understanding of synaptic transmission and its integration when employing classical electrophysiological approaches. Indeed, electrical field stimulation delivered via traditional microelectrodes does not permit the targeted, precise and selective control of neuronal activity amongst a varied population of neurons and their inputs (eg, cholinergic, dopaminergic or glutamatergic neurons). Recently established optogenetic techniques overcome these limitations allowing precise control of the target neuron populations, which is essential for the elucidation of the neural substrates underlying complex animal behaviors. Indeed, by introducing light-activated channels (ie, microbial opsin genes) into specific neuronal populations, optogenetics enables non-invasive optical control of specific neurons with milliseconds precision. These approaches can readily be applied to freely behaving live animals. Recently there is increased interests in utilizing optogenetics tools to understand synaptic plasticity and learning/memory. Here, we summarize recent progress in applying optogenetics in in the study of synaptic plasticity. PMID:24162508

Xie, Yu-feng; Jackson, Michael F; MacDonald, John F

2013-01-01

448

46 CFR 194.05-7 - Explosives-Detail requirements.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Explosives-Detail requirements. 194...HANDLING, USE, AND CONTROL OF EXPLOSIVES AND OTHER HAZARDOUS MATERIALS Stowage and Marking § 194.05-7 Explosives—Detail requirements....

2013-10-01

449

29 CFR 1926.902 - Surface transportation of explosives.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Surface transportation of explosives. 1926.902 Section 1926.902...CONSTRUCTION Blasting and the Use of Explosives § 1926.902 Surface transportation of explosives. (a) Transportation of...

2012-07-01

450

27 CFR 70.445 - Commerce in explosives.  

...2014-04-01 false Commerce in explosives. 70.445 Section 70.445...Alcohol, Tobacco, Firearms, and Explosives Provisions Relating to Firearms, Shells and Cartridges, and Explosives § 70.445 Commerce in...

2014-04-01

451

30 CFR 56.6900 - Damaged or deteriorated explosive material.  

Code of Federal Regulations, 2011 CFR

... false Damaged or deteriorated explosive material. 56.6900 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6900 Damaged or deteriorated explosive material. Damaged or...

2011-07-01

452

30 CFR 57.6201 - Separation of transported explosive material.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Separation of transported explosive material. 57.6201 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground...57.6201 Separation of transported explosive material. Detonators shall not...

2012-07-01

453

30 CFR 75.1311 - Transporting explosives and detonators.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Transporting explosives and detonators. 75.1311 Section...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1311 Transporting explosives and detonators. (a) When...

2010-07-01

454

30 CFR 57.6960 - Mixing of explosive material.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Mixing of explosive material. 57.6960 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Underground Only § 57.6960 Mixing of explosive material. (a) The mixing...

2011-07-01

455

30 CFR 57.6100 - Separation of stored explosive material.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Separation of stored explosive material. 57.6100 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Storage-Surface and Underground § 57.6100 Separation of stored explosive material. (a) Detonators...

2011-07-01

456

30 CFR 56.6900 - Damaged or deteriorated explosive material.  

Code of Federal Regulations, 2012 CFR

... false Damaged or deteriorated explosive material. 56.6900 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6900 Damaged or deteriorated explosive material. Damaged or...

2012-07-01

457

30 CFR 56.6100 - Separation of stored explosive material.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Separation of stored explosive material. 56.6100 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Storage § 56.6100 Separation of stored explosive material. (a) Detonators shall...

2013-07-01

458

27 CFR 70.445 - Commerce in explosives.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Commerce in explosives. 70.445 Section 70.445...Alcohol, Tobacco, Firearms, and Explosives Provisions Relating to Firearms, Shells and Cartridges, and Explosives § 70.445 Commerce in...

2010-04-01

459

30 CFR 57.6102 - Explosive material storage practices.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Explosive material storage practices. 57.6102...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Storage-Surface and Underground § 57.6102 Explosive material storage practices. (a)...

2012-07-01

460

30 CFR 77.1303 - Explosives, handling and use.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Explosives, handling and use. 77.1303 Section...SURFACE WORK AREAS OF UNDERGROUND COAL MINES Explosives and Blasting § 77.1303 Explosives, handling and use. (a) Persons...

2013-07-01

461

30 CFR 75.1314 - Sheathed explosive units.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Sheathed explosive units. 75.1314 Section 75.1314...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1314 Sheathed explosive units. (a) A separate...

2013-07-01

462

30 CFR 57.6201 - Separation of transported explosive material.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Separation of transported explosive material. 57.6201 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Transportation-Surface and Underground...57.6201 Separation of transported explosive material. Detonators shall not...

2013-07-01

463

30 CFR 57.6130 - Explosive material storage facilities.  

...2014-07-01 2014-07-01 false Explosive material storage facilities. 57.6130...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Storage-Surface Only § 57.6130 Explosive material storage facilities. (a)...

2014-07-01

464

30 CFR 75.1310 - Explosives and blasting equipment.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Explosives and blasting equipment. 75.1310 Section...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1310 Explosives and blasting equipment. (a) Only...

2010-07-01

465

30 CFR 57.6900 - Damaged or deteriorated explosive material.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Damaged or deteriorated explosive material. 57.6900 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and...57.6900 Damaged or deteriorated explosive material. Damaged or...

2011-07-01

466

30 CFR 75.1310 - Explosives and blasting equipment.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Explosives and blasting equipment. 75.1310 Section...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1310 Explosives and blasting equipment. (a) Only...

2011-07-01

467

30 CFR 57.6100 - Separation of stored explosive material.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Separation of stored explosive material. 57.6100 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Storage-Surface and Underground § 57.6100 Separation of stored explosive material. (a) Detonators...

2010-07-01

468

30 CFR 56.6100 - Separation of stored explosive material.  

...2014-07-01 false Separation of stored explosive material. 56.6100 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Storage § 56.6100 Separation of stored explosive material. (a) Detonators shall...

2014-07-01

469

30 CFR 56.6201 - Separation of transported explosive material.  

Code of Federal Regulations, 2012 CFR

... false Separation of transported explosive material. 56.6201 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Transportation § 56.6201 Separation of transported explosive material. Detonators shall...

2012-07-01

470

30 CFR 57.6960 - Mixing of explosive material.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Mixing of explosive material. 57.6960 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Underground Only § 57.6960 Mixing of explosive material. (a) The mixing...

2010-07-01

471

30 CFR 57.6960 - Mixing of explosive material.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Mixing of explosive material. 57.6960 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Underground Only § 57.6960 Mixing of explosive material. (a) The mixing...

2013-07-01

472

30 CFR 75.1314 - Sheathed explosive units.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Sheathed explosive units. 75.1314 Section 75.1314...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1314 Sheathed explosive units. (a) A separate...

2012-07-01

473

29 CFR 1926.902 - Surface transportation of explosives.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Surface transportation of explosives. 1926.902 Section 1926.902...CONSTRUCTION Blasting and the Use of Explosives § 1926.902 Surface transportation of explosives. (a) Transportation of...

2013-07-01

474

33 CFR 401.68 - Explosives Permission Letter.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Explosives Permission Letter. 401.68 Section...Regulations Dangerous Cargo § 401.68 Explosives Permission Letter. (a) A Seaway Explosives Permission Letter is required for an...

2011-07-01

475

30 CFR 75.1311 - Transporting explosives and detonators.  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Transporting explosives and detonators. 75.1311 Section...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1311 Transporting explosives and detonators. (a) When...

2012-07-01

476

30 CFR 57.6900 - Damaged or deteriorated explosive material.  

...2014-07-01 false Damaged or deteriorated explosive material. 57.6900 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and...57.6900 Damaged or deteriorated explosive material. Damaged or...

2014-07-01

477

30 CFR 77.1302 - Vehicles used to transport explosives.  

Code of Federal Regulations, 2013 CFR

... false Vehicles used to transport explosives. 77.1302 Section 77.1302...WORK AREAS OF UNDERGROUND COAL MINES Explosives and Blasting § 77.1302 Vehicles used to transport explosives. (a) Vehicles used to...

2013-07-01

478

30 CFR 56.6900 - Damaged or deteriorated explosive material.  

Code of Federal Regulations, 2013 CFR

... false Damaged or deteriorated explosive material. 56.6900 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6900 Damaged or deteriorated explosive material. Damaged or...

2013-07-01

479

30 CFR 57.6102 - Explosive material storage practices.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Explosive material storage practices. 57.6102...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Storage-Surface and Underground § 57.6102 Explosive material storage practices. (a)...

2011-07-01

480

30 CFR 75.1314 - Sheathed explosive units.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Sheathed explosive units. 75.1314 Section 75.1314...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1314 Sheathed explosive units. (a) A separate...

2011-07-01

481

Combinatorial explosion in model gene networks R. Edwardsa)  

E-print Network

Combinatorial explosion in model gene networks R. Edwardsa) Department of Mathematics Received 31 January 2000; accepted for publication 16 May 2000 The explosive growth in knowledge here that there is actually a combinatorial explosion of different logical structures possible

Glass, Leon

482

30 CFR 75.1310 - Explosives and blasting equipment.  

...2014-07-01 2014-07-01 false Explosives and blasting equipment. 75.1310 Section...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1310 Explosives and blasting equipment. (a) Only...

2014-07-01

483

30 CFR 57.6100 - Separation of stored explosive material.  

...2014-07-01 false Separation of stored explosive material. 57.6100 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Storage-Surface and Underground § 57.6100 Separation of stored explosive material. (a) Detonators...

2014-07-01

484

30 CFR 57.6900 - Damaged or deteriorated explosive material.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Damaged or deteriorated explosive material. 57.6900 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and...57.6900 Damaged or deteriorated explosive material. Damaged or...

2013-07-01

485

33 CFR 401.68 - Explosives Permission Letter.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Explosives Permission Letter. 401.68 Section...Regulations Dangerous Cargo § 401.68 Explosives Permission Letter. (a) A Seaway Explosives Permission Letter is required for an...

2012-07-01

486

30 CFR 56.6201 - Separation of transported explosive material.  

... false Separation of transported explosive material. 56.6201 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Transportation § 56.6201 Separation of transported explosive material. Detonators shall...

2014-07-01

487

30 CFR 77.1303 - Explosives, handling and use.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Explosives, handling and use. 77.1303 Section...SURFACE WORK AREAS OF UNDERGROUND COAL MINES Explosives and Blasting § 77.1303 Explosives, handling and use. (a) Persons...

2012-07-01

488

30 CFR 57.6100 - Separation of stored explosive material.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Separation of stored explosive material. 57.6100 Section...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Storage-Surface and Underground § 57.6100 Separation of stored explosive material. (a) Detonators...

2013-07-01

489

30 CFR 57.6102 - Explosive material storage practices.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Explosive material storage practices. 57.6102...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Storage-Surface and Underground § 57.6102 Explosive material storage practices. (a)...

2010-07-01

490

30 CFR 56.6900 - Damaged or deteriorated explosive material.  

... false Damaged or deteriorated explosive material. 56.6900 Section 56...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives General Requirements § 56.6900 Damaged or deteriorated explosive material. Damaged or...

2014-07-01

491

30 CFR 57.6130 - Explosive material storage facilities.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Explosive material storage facilities. 57.6130...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Storage-Surface Only § 57.6130 Explosive material storage facilities. (a)...

2013-07-01

492

30 CFR 57.6102 - Explosive material storage practices.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Explosive material storage practices. 57.6102...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Storage-Surface and Underground § 57.6102 Explosive material storage practices. (a)...

2013-07-01

493

30 CFR 77.1302 - Vehicles used to transport explosives.  

... false Vehicles used to transport explosives. 77.1302 Section 77.1302...WORK AREAS OF UNDERGROUND COAL MINES Explosives and Blasting § 77.1302 Vehicles used to transport explosives. (a) Vehicles used to...

2014-07-01

494

30 CFR 57.6130 - Explosive material storage facilities.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Explosive material storage facilities. 57.6130...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Storage-Surface Only § 57.6130 Explosive material storage facilities. (a)...

2012-07-01

495

30 CFR 77.1302 - Vehicles used to transport explosives.  

Code of Federal Regulations, 2011 CFR

... false Vehicles used to transport explosives. 77.1302 Section 77.1302...WORK AREAS OF UNDERGROUND COAL MINES Explosives and Blasting § 77.1302 Vehicles used to transport explosives. (a) Vehicles used to...

2011-07-01

496

30 CFR 75.1311 - Transporting explosives and detonators.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Transporting explosives and detonators. 75.1311 Section...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1311 Transporting explosives and detonators. (a) When...

2013-07-01

497

27 CFR 70.445 - Commerce in explosives.  

Code of Federal Regulations, 2012 CFR

...2011-04-01 true Commerce in explosives. 70.445 Section 70.445...Alcohol, Tobacco, Firearms, and Explosives Provisions Relating to Firearms, Shells and Cartridges, and Explosives § 70.445 Commerce in...

2012-04-01

498

30 CFR 57.6900 - Damaged or deteriorated explosive material.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Damaged or deteriorated explosive material. 57.6900 Section 57...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives General Requirements-Surface and...57.6900 Damaged or deteriorated explosive material. Damaged or...

2012-07-01

499

THE EXPLOSION TIME IN STOCHASTIC DIFFERENTIAL EQUATIONS WITH SMALL  

E-print Network

THE EXPLOSION TIME IN STOCHASTIC DIFFERENTIAL EQUATIONS WITH SMALL, under suitable hypotheses, the explosion time converges almost surely to the one of the ODE. 1. Introduction Explosions in one dimensional ODEs is a very well known phenom- ena. Let u

Rossi, Julio D.

500

30 CFR 75.1311 - Transporting explosives and detonators.  

... 2014-07-01 false Transporting explosives and detonators. 75.1311 Section...SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1311 Transporting explosives and detonators. (a) When...

2014-07-01