30 CFR 7.306 - Explosion tests.

Code of Federal Regulations, 2011 CFR

2011-07-01

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

Modular initiator with integrated optical diagnostic

DOEpatents

Alam, M Kathleen [Cedar Crest, NM; Schmitt, Randal L [Tijeras, NM; Welle, Eric J [Niceville, FL; Madden, Sean P [Arlington, MA

2011-05-17

A slapper detonator which integrally incorporates an optical wavequide structure for determining whether there has been degradation of the explosive in the explosive device that is to be initiated by the detonator. Embodiments of this invention take advantage of the barrel-like character of a typical slapper detonator design. The barrel assembly, being in direct contact with the energetic material, incorporates an optical diagnostic device into the barrel assembly whereby one can monitor the state of the explosive material. Such monitoring can be beneficial because the chemical degradation of the explosive plays an important in achieving proper functioning of a detonator/initiator device.

The behavior limestone under explosive load

NASA Astrophysics Data System (ADS)

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

2016-11-01

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

30 CFR 56.6602 - Static electricity dissipation during loading.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Static electricity dissipation during loading... Explosives Extraneous Electricity § 56.6602 Static electricity dissipation during loading. When explosive material is loaded pneumatically into a blasthole in a manner that generates a static electricity hazard...

30 CFR 56.6602 - Static electricity dissipation during loading.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Static electricity dissipation during loading... Explosives Extraneous Electricity § 56.6602 Static electricity dissipation during loading. When explosive material is loaded pneumatically into a blasthole in a manner that generates a static electricity hazard...

30 CFR 56.6602 - Static electricity dissipation during loading.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Static electricity dissipation during loading... Explosives Extraneous Electricity § 56.6602 Static electricity dissipation during loading. When explosive material is loaded pneumatically into a blasthole in a manner that generates a static electricity hazard...

30 CFR 56.6602 - Static electricity dissipation during loading.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Static electricity dissipation during loading... Explosives Extraneous Electricity § 56.6602 Static electricity dissipation during loading. When explosive material is loaded pneumatically into a blasthole in a manner that generates a static electricity hazard...

30 CFR 56.6602 - Static electricity dissipation during loading.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Static electricity dissipation during loading... Explosives Extraneous Electricity § 56.6602 Static electricity dissipation during loading. When explosive material is loaded pneumatically into a blasthole in a manner that generates a static electricity hazard...

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

NASA Astrophysics Data System (ADS)

Ji, Wendong; Yang, Ligong; Chen, Lin

2018-05-01

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

Surface Instabilities From Buried Explosives

DTIC Science & Technology

2009-07-21

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

30 CFR 57.6307 - Drill stem loading.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Drill stem loading. 57.6307 Section 57.6307... Transportation-Surface and Underground § 57.6307 Drill stem loading. Explosive material shall not be loaded into blastholes with drill stem equipment or other devices that could be extracted while containing explosive...

30 CFR 57.6307 - Drill stem loading.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Drill stem loading. 57.6307 Section 57.6307... Transportation-Surface and Underground § 57.6307 Drill stem loading. Explosive material shall not be loaded into blastholes with drill stem equipment or other devices that could be extracted while containing explosive...

30 CFR 57.6307 - Drill stem loading.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Drill stem loading. 57.6307 Section 57.6307... Transportation-Surface and Underground § 57.6307 Drill stem loading. Explosive material shall not be loaded into blastholes with drill stem equipment or other devices that could be extracted while containing explosive...

30 CFR 57.6307 - Drill stem loading.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Drill stem loading. 57.6307 Section 57.6307... Transportation-Surface and Underground § 57.6307 Drill stem loading. Explosive material shall not be loaded into blastholes with drill stem equipment or other devices that could be extracted while containing explosive...

30 CFR 57.6307 - Drill stem loading.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drill stem loading. 57.6307 Section 57.6307... Transportation-Surface and Underground § 57.6307 Drill stem loading. Explosive material shall not be loaded into blastholes with drill stem equipment or other devices that could be extracted while containing explosive...

Organic supernanostructures self-assembled via solution process for explosive detection.

PubMed

Wang, Lei; Zhou, Yan; Yan, Jing; Wang, Jian; Pei, Jian; Cao, Yong

2009-02-03

Three different polymorphic crystalline structures, including microbelts and flowerlike supernanostructures, were obtained via a simple solution process by utilizing different solvents from an oligoarene derivative. Explosive chemosensors based on these self-assembled organic crystalline nanostructures were successfully fabricated. The differences in the structures on the microscopic level and in the film morphologies led to dramatic enhancements of the explosive detection speed. With the evolution of structures from the netted 1D microbelts to the flowerlike supernanostructures, the detection speed of the chemosensors for DNT and TNT was improved by more than 700 times. Our discovery demonstrates that the morphology control through self-assembly provides a new platform to utilize organic crystalline microstructures for chemosensors, optoelectronics, biosensors and bioelectronics, and so forth.

29 CFR 1926.905 - Loading of explosives or blasting agents.

Code of Federal Regulations, 2012 CFR

2012-07-01

... have contained explosives or blasting agents. (g) No explosives or blasting agents shall be left... no drilling within 50 feet of the hole. (l) When loading a long line of holes with more than one... be left unattended or unprotected. (t) The blaster shall keep an accurate, up-to-date record of...

29 CFR 1926.905 - Loading of explosives or blasting agents.

Code of Federal Regulations, 2013 CFR

2013-07-01

... have contained explosives or blasting agents. (g) No explosives or blasting agents shall be left... no drilling within 50 feet of the hole. (l) When loading a long line of holes with more than one... be left unattended or unprotected. (t) The blaster shall keep an accurate, up-to-date record of...

29 CFR 1926.905 - Loading of explosives or blasting agents.

Code of Federal Regulations, 2014 CFR

2014-07-01

... have contained explosives or blasting agents. (g) No explosives or blasting agents shall be left... no drilling within 50 feet of the hole. (l) When loading a long line of holes with more than one... be left unattended or unprotected. (t) The blaster shall keep an accurate, up-to-date record of...

29 CFR 1926.905 - Loading of explosives or blasting agents.

Code of Federal Regulations, 2011 CFR

2011-07-01

... have contained explosives or blasting agents. (g) No explosives or blasting agents shall be left... no drilling within 50 feet of the hole. (l) When loading a long line of holes with more than one... be left unattended or unprotected. (t) The blaster shall keep an accurate, up-to-date record of...

Field repair of AH-16 helicopter window cutting assemblies

NASA Technical Reports Server (NTRS)

Bement, L. J.

1984-01-01

The U.S. Army uses explosively actuated window cutting assemblies to provide emergency crew ground egress. Gaps between the system's explosive cords and acrylic windows caused a concern about functional reliability for a fleet of several hundred aircraft. A field repair method, using room temperature vulcanizing silicone compound (RTV), was developed and demonstrated to fill gaps as large as 0.250 inch.

Unknown loads affect force production capacity in early phases of bench press throws.

PubMed

Hernández Davó, J L; Sabido Solana, R; Sarabia Marínm, J M; Sánchez Martos, Á; Moya Ramón, M

2015-10-01

Explosive strength training aims to improve force generation in early phases of movement due to its importance in sport performance. The present study examined the influence of lack of knowledge about the load lifted in explosive parameters during bench press throws. Thirteen healthy young men (22.8±2.0 years) participated in the study. Participants performed bench press throws with three different loads (30, 50 and 70% of 1 repetition maximum) in two different conditions (known and unknown loads). In unknown condition, loads were changed within sets in each repetition and participants did not know the load, whereas in known condition the load did not change within sets and participants had knowledge about the load lifted. Results of repeated-measures ANOVA revealed that unknown conditions involves higher power in the first 30, 50, 100 and 150 ms with the three loads, higher values of ratio of force development in those first instants, and differences in time to reach maximal rate of force development with 50 and 70% of 1 repetition maximum. This study showed that unknown conditions elicit higher values of explosive parameters in early phases of bench press throws, thereby this kind of methodology could be considered in explosive strength training.

Explosive Fracturing of an F-16 Canopy for Through-Canopy Crew Egress

NASA Technical Reports Server (NTRS)

Bement, Laurence J.

2000-01-01

Through-canopy crew egress, such as in the Harrier (AV-8B) aircraft, expands escape envelopes by reducing seat ejection delays in waiting for canopy jettison. Adverse aircraft attitude and reduced forward flight speed can further increase the times for canopy jettison. However, the advent of heavy, high-strength polycarbonate canopies for bird-strike resistance has not only increased jettison times, but has made seat penetration impossible. The goal of the effort described in this paper was to demonstrate a method of explosively fracturing the F-16 polycarbonate canopy to allow through-canopy crew ejection. The objectives of this effort were to: 1. Mount the explosive materials on the exterior of the canopy within the mold line, 2. Minimize visual obstructions, 3. Minimize internal debris on explosive activation, 4. Operate within less than 10 ms, 5. Maintain the shape of the canopy after functioning to prevent major pieces from entering the cockpit, and 6. Minimize the resistance of the canopy to seat penetration. All goals and objectives were met in a full-scale test demonstration. In addition to expanding crew escape envelopes, this canopy fracture approach offers the potential for reducing system complexity, weight and cost, while increasing overall reliability, compared to current canopy jettison approaches. To comply with International Traffic in Arms Regulations (ITAR) and permit public disclosure, this document addresses only the principles of explosive fracturing of the F-16 canopy materials and the end result. ITAR regulations restrict information on improving the performance of weapon systems. Therefore, details on the explosive loads and final assembly of this canopy fracture approach, necessary to assure functional performance, are not included.

Interplay of explosive thermal reaction dynamics and structural confinement

NASA Astrophysics Data System (ADS)

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

2007-04-01

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

Explosive Joining for Nuclear-Reactor Repair

NASA Technical Reports Server (NTRS)

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

1983-01-01

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

Manual for the prediction of blast and fragment loadings on structures

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

Not Available

1980-11-01

The purpose of this manual is to provide Architect-Engineer (AE) firms guidance for the prediction of air blast, ground shock and fragment loadings on structures as a result of accidental explosions in or near these structures. Information in this manual is the result of an extensive literature survey and data gathering effort, supplemented by some original analytical studies on various aspects of blast phenomena. Many prediction equations and graphs are presented, accompanied by numerous example problems illustrating their use. The manual is complementary to existing structural design manuals and is intended to reflect the current state-of-the-art in prediction of blastmore » and fragment loads for accidental explosions of high explosives at the Pantex Plant. In some instances, particularly for explosions within blast-resistant structures of complex geometry, rational estimation of these loads is beyond the current state-of-the-art.« less

27 CFR 555.201 - General.

Code of Federal Regulations, 2011 CFR

2011-04-01

... fireworks, pyrotechnic compositions, and explosive materials used in assembling fireworks and articles pyrotechnic. (e) The provisions of § 555.202(a) classifying flash powder and bulk salutes as high explosives...

27 CFR 555.201 - General.

Code of Federal Regulations, 2010 CFR

2010-04-01

... fireworks, pyrotechnic compositions, and explosive materials used in assembling fireworks and articles pyrotechnic. (e) The provisions of § 555.202(a) classifying flash powder and bulk salutes as high explosives...

Template-directed synthesis of silica nanotubes for explosive detection.

PubMed

Yildirim, Adem; Acar, Handan; Erkal, Turan S; Bayindir, Mehmet; Guler, Mustafa O

2011-10-01

Fluorescent porous organic-inorganic thin films are of interest of explosive detection because of their vapor phase fluorescence quenching property. In this work, we synthesized fluorescent silica nanotubes using a biomineralization process through self-assembled peptidic nanostructures. We designed and synthesized an amyloid-like peptide self-assembling into nanofibers to be used as a template for silica nanotube formation. The amine groups on the peptide nanofibrous system were used for nucleation of silica nanostructures. Silica nanotubes were used to prepare highly porous surfaces, and they were doped with a fluorescent dye by physical adsorption for explosive sensing. These porous surfaces exhibited fast, sensitive, and highly selective fluorescence quenching against nitro-explosive vapors. The materials developed in this work have vast potential in sensing applications due to enhanced surface area. © 2011 American Chemical Society

Comparing CTH Simulations and Experiments on Explosively Loaded Rings

NASA Astrophysics Data System (ADS)

Braithwaite, C. H.; Aydelotte, B.; Thadhani, N. N.; Williamson, D. M.

2011-06-01

A series of experiments were conducted on explosively loaded rings for the purpose of studying fragmentation. In addition to the collection of fragments for analysis, the radial velocity of the expanding ring was measured with PDV and the arrangement was imaged using a high speed camera. Both the ring material and the material used as the explosive container were altered and the results compared with simulations performed in CTH. Good agreement was found between the simulations and the experiments. The maximum radial velocity attained was approximately 450 m/s, which was achieved through loading with a 5g PETN based charge.

Multichannel Discriminative Detection of Explosive Vapors with an Array of Nanofibrous Membranes Loaded with Quantum Dots.

PubMed

Wu, Zhaofeng; Duan, Haiming; Li, Zhijun; Guo, Jixi; Zhong, Furu; Cao, Yali; Jia, Dianzeng

2017-11-20

The multichannel fluorescent sensor array based on nanofibrous membranes loaded with ZnS quantum dots (QDs) was created and demonstrated for the discriminative detection of explosives. The synergistic effect of the high surface-to-volume ratio of QDs, the good permeability of nanofibrous membranes and the differential response introduced by surface ligands was played by constructing the sensing array using nanofibrous membranes loaded with ZnS QDs featuring several surface ligands. Interestingly, although the fluorescence quenching of the nanofibrous membranes is not linearly related to the exposure time, the fingerprint of each explosive at different times is very similar in shape, and the fingerprints of the three explosives show different shapes. Three saturated vapors of nitroaromatic explosives could be reliably detected and discriminated by the array at room temperature. This work is the first step toward devising a monitoring system for explosives in the field of public security and defense. It could, for example, be coupled with the technology of image recognition and large data analysis for a rapid diagnostic test of explosives. This work further highlights the power of differential, multichannel arrays for the rapid and discriminative detection of a wide range of chemicals.

Multichannel Discriminative Detection of Explosive Vapors with an Array of Nanofibrous Membranes Loaded with Quantum Dots

PubMed Central

Wu, Zhaofeng; Duan, Haiming; Li, Zhijun; Guo, Jixi; Zhong, Furu; Cao, Yali; Jia, Dianzeng

2017-01-01

The multichannel fluorescent sensor array based on nanofibrous membranes loaded with ZnS quantum dots (QDs) was created and demonstrated for the discriminative detection of explosives. The synergistic effect of the high surface-to-volume ratio of QDs, the good permeability of nanofibrous membranes and the differential response introduced by surface ligands was played by constructing the sensing array using nanofibrous membranes loaded with ZnS QDs featuring several surface ligands. Interestingly, although the fluorescence quenching of the nanofibrous membranes is not linearly related to the exposure time, the fingerprint of each explosive at different times is very similar in shape, and the fingerprints of the three explosives show different shapes. Three saturated vapors of nitroaromatic explosives could be reliably detected and discriminated by the array at room temperature. This work is the first step toward devising a monitoring system for explosives in the field of public security and defense. It could, for example, be coupled with the technology of image recognition and large data analysis for a rapid diagnostic test of explosives. This work further highlights the power of differential, multichannel arrays for the rapid and discriminative detection of a wide range of chemicals. PMID:29156627

Encyclopedia of Explosives and Related Items. Volume 8

DTIC Science & Technology

1978-01-01

up", becoming hard and making Alcohol(b), % 20 ± 2 19 ± 2 a reliable joint . Shellac is used to coat cavities Shellac(c) % 18±2 - to be loaded with...P 380 Effect of Loading Pressure on Initiator Sensitivity ...................... P 382 Stab Primer Data...Injection Loading Operation Schematic .............................. P 64 Continuous Explosive Column for Use with Zuni Weapon ................... P 64

The Shock and Vibration Bulletin. Part 4. Impact, Packaging and Shipping, Blast and Impulsive Loading

DTIC Science & Technology

1975-06-01

Explosive forces are completely through undisturbed air where appreciable dominant and the plate is rotated through an aerodynamic forces retard its...are relatively of the explosive system drops rapidly with dense compared to air , do produce sufficient flyer thickness, little is gained by increasing...impulsive loadings generated by a fuel air explosive . A membrane model based on a total plastic strain energy function, a rigid strain hardening

Effect of load carriage on performance of an explosive, anaerobic military task.

PubMed

Treloar, Alison K Laing; Billing, Daniel C

2011-09-01

This study examined the effects of load carriage on performance of an explosive, anaerobic military task. A task-specific assessment requiring five 30-m timed sprints was developed to address this question. Seventeen soldiers (female = 5, male = 12) volunteered to undergo the test under two experimental conditions: unloaded (combat uniform and boots) and loaded (unloaded plus 21.6 kg fighting load, comprising webbing, weapon, helmet, and combat body armor). When loaded, there was a significant increase in the mean 30-m sprint time compared to unloaded (8.2 +/- 1.4 seconds vs. 6.2 +/- 0.8 seconds; p < 0.01). Of the total increase in mean sprint time, 51.7% occurred within the first 5 m. Female sprint times were affected to a larger extent than male (36% vs. 29%, respectively) as a result of the increased load. Fighting load significantly affected soldier mobility when conducting explosive, anaerobic military tasks, particularly among females, and specific physical conditioning should be considered to minimize this effect.

Comparing CTH simulations and experiments on explosively loaded rings

NASA Astrophysics Data System (ADS)

Braithwaite, C. H.; Aydelotte, Brady; Collins, Adam; Thadhani, Naresh; Williamson, David Martin

2012-03-01

A series of experiments were conducted on explosively loaded metallic rings for the purpose of studying fragmentation. In addition to the collection of fragments for analysis, the radial velocity of the expanding ring was measured with photon Doppler velocimetry (PDV) and the arrangement was imaged using high speed photography. Both the ring material and the material used as the explosive container were altered and the results compared with simulations performed in CTH. Good agreement was found between the simulations and the experiments. The maximum radial velocity attained was approximately 380 m/s, which was achieved through loading with a 5g PETN based charge.

Tube swaging device uses explosive force

NASA Technical Reports Server (NTRS)

Mc Smith, D. G.

1968-01-01

Tool joins a sleeve to a tube by explosive swaging, thus providing a leakproof, lightweight, and strong assembly. No new or different material is used in this method and therefore the thermal and galvanic properties are maintained.

Modelling and Testing of Blast Effect On the Structures

NASA Astrophysics Data System (ADS)

Figuli, Lucia; Jangl, Štefan; Papán, Daniel

2016-10-01

As a blasting agent in the blasting and mining engineering, has been using one of so called new generation of explosives which offer greater flexibility in their range and application, and such explosive is ANFO. It is type of explosive consists of an oxidiser and a fuel (ammonium nitrate and fuel oil). One of such ANFO explosives which are industrially made in Slovakia is POLONIT. The explosive is a mixture of ammonium nitrate, methyl esters of higher fatty acids, vegetable oil and red dye. The paper deals with the analysis of structure subjected to the blast load created by the explosion of POLONIT charge. First part of paper is describing behaviour and characteristic of blast wave generated from the blast (detonation characteristics, physical characteristics, time-history diagram etc.) and the second part presents the behaviour of such loaded structures, because of the analysis of such dynamical loaded structure is required knowing the parameters of blast wave, its effect on structure and the tools for the solution of dynamic analysis. The real field tests of three different weight of charges and two different structures were done. The explosive POLONIT was used together with 25 g of ignition explosive PLNp10. Analytical and numerical model of blast loaded structure is compared with the results obtained from the field tests (is compared with the corresponding experimental accelerations). For the modelling structures were approximated as a one-degree system of freedom (SDOF), where the blast wave was estimated with linear decay and exponential decay using positive and negative phase of blast wave. Numerical solution of the steel beam dynamic response was performed via FEM (Finite Element Method) using standard software Visual FEA.

Transient/structural analysis of a combustor under explosive loads

NASA Technical Reports Server (NTRS)

Gregory, Peyton B.; Holland, Anne D.

1992-01-01

The 8-Foot High Temperature Tunnel (HTT) at NASA Langley Research Center is a combustion-driven blow-down wind tunnel. A major potential failure mode that was considered during the combustor redesign was the possibility of a deflagration and/or detonation in the combustor. If a main burner flame-out were to occur, then unburned fuel gases could accumulate and, if reignited, an explosion could occur. An analysis has been performed to determine the safe operating limits of the combustor under transient explosive loads. The failure criteria was defined and the failure mechanisms were determined for both peak pressures and differential pressure loadings. An overview of the gas dynamics analysis was given. A finite element model was constructed to evaluate 13 transient load cases. The sensitivity of the structure to the frequency content of the transient loading was assessed. In addition, two closed form dynamic analyses were conducted to verify the finite element analysis. It was determined that the differential pressure load or thrust load was the critical load mechanism and that the nozzle is the weak link in the combustor system.

49 CFR 176.182 - Conditions for handling on board ship.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Class 1 (explosive) materials. During electrical storms, cargo operations must be halted and all hatches...) All hatches and cargo ports opening into a compartment in which Class 1 (explosive) materials are stowed must be kept closed except during loading and unloading of the compartment. After loading, hatches...

49 CFR 176.182 - Conditions for handling on board ship.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Class 1 (explosive) materials. During electrical storms, cargo operations must be halted and all hatches...) All hatches and cargo ports opening into a compartment in which Class 1 (explosive) materials are stowed must be kept closed except during loading and unloading of the compartment. After loading, hatches...

49 CFR 176.182 - Conditions for handling on board ship.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Class 1 (explosive) materials. During electrical storms, cargo operations must be halted and all hatches...) All hatches and cargo ports opening into a compartment in which Class 1 (explosive) materials are stowed must be kept closed except during loading and unloading of the compartment. After loading, hatches...

49 CFR 176.182 - Conditions for handling on board ship.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Class 1 (explosive) materials. During electrical storms, cargo operations must be halted and all hatches...) All hatches and cargo ports opening into a compartment in which Class 1 (explosive) materials are stowed must be kept closed except during loading and unloading of the compartment. After loading, hatches...

A study of an advanced confined linear energy source

NASA Technical Reports Server (NTRS)

Anderson, M. C.; Heidemann, W. B.

1971-01-01

A literature survey and a test program to develop and evaluate an advanced confined linear energy source were conducted. The advanced confined linear energy source is an explosive or pyrotechnic X-Cord (mild detonating fuse) supported inside a confining tube capable of being hermetically sealed and retaining all products of combustion. The energy released by initiation of the X-Cord is transmitted through the support material to the walls of the confining tube causing an appreciable change in cross sectional configuration and expansion of the tube. When located in an assembly that can accept and use the energy of the tube expansion, useful work is accomplished through fracture of a structure, movement of a load, reposition of a pin, release of a restraint, or similar action. The tube assembly imparts that energy without release of debris or gases from the device itself. This facet of the function is important to the protection of men or equipment located in close proximity to the system during the time of function.

Cylinder Test Specification

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

Richard Catanach; Larry Hill; Herbert Harry

1999-10-01

The purpose of the cylinder testis two-fold: (1) to characterize the metal-pushing ability of an explosive relative to that of other explosives as evaluated by the E{sub 19} cylinder energy and the G{sub 19} Gurney energy and (2) to help establish the explosive product equation-of-state (historically, the Jones-Wilkins-Lee (JWL) equation). This specification details the material requirements and procedures necessary to assemble and fire a typical Los Alamos National Laboratory (LANL) cylinder test. Strict adherence to the cylinder. material properties, machining tolerances, material heat-treatment and etching processes, and high explosive machining tolerances is essential for test-to-test consistency and to maximize radialmore » wall expansions. Assembly and setup of the cylinder test require precise attention to detail, especially when placing intricate pin wires on the cylinder wall. The cylinder test is typically fired outdoors and at ambient temperature.« less

Dissolution and sorption of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT) residues from detonated mineral surfaces.

PubMed

Jaramillo, Ashley M; Douglas, Thomas A; Walsh, Marianne E; Trainor, Thomas P

2011-08-01

Composition B (Comp B) is a commonly used military formulation composed of the toxic explosive compounds 2,4,6-trinitrotoluene (TNT), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). Numerous studies of the temporal fate of explosive compounds in soils, surface water and laboratory batch reactors have been conducted. However, most of these investigations relied on the application of explosive compounds to the media via aqueous addition and thus these studies do not provide information on the real world loading of explosive residues during detonation events. To address this we investigated the dissolution and sorption of TNT and RDX from Comp B residues loaded to pure mineral phases through controlled detonation. Mineral phases included nontronite, vermiculite, biotite and Ottawa sand (quartz with minor calcite). High Performance Liquid Chromatography and Attenuated Total Reflectance Fourier Transform Infrared spectroscopy were used to investigate the dissolution and sorption of TNT and RDX residues loaded onto the mineral surfaces. Detonation resulted in heterogeneous loading of TNT and RDX onto the mineral surfaces. Explosive compound residues dissolved rapidly (within 9 h) in all samples but maximum concentrations for TNT and RDX were not consistent over time due to precipitation from solution, sorption onto mineral surfaces, and/or chemical reactions between explosive compounds and mineral surfaces. We provide a conceptual model of the physical and chemical processes governing the fate of explosive compound residues in soil minerals controlled by sorption-desorption processes. Published by Elsevier Ltd.

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

PubMed

Wu, Y Q; Huang, F L

2010-11-15

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

Flash Radiographic Studies of Hypervelocity Projectile Interactions with Explosives

DTIC Science & Technology

1992-07-01

radiography . Explosive/metal target assemblies were designed to be representative of various aspects of explosive filled ordnance or components. The...with Explosives 1. Introduction Flash radiography (flash X-ray) is an effective instrumentation technique that can be used to record ultra high speed...firing chamber and provide a stable mount for the X-ray tubehead. i_ 11 611 Fmim A \\.\\\\ / \\,\\\\ // "-.. .•\\ /i--" " "’ ’i Xray source ColliatorBase X-ray

Full scale remediation of an explosives-contaminated site at Yorktown Naval Weapons Station using the SABRE{trademark} process

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

Kaake, R.H.; Bono, J.; Yergovich, T.

Characterization of a former weapons loading and assembly facility identified soil contaminated with the explosives TNT (2,4,6-trinitrotoluene) and RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine). The site contains of a variety of discrete soil types that include clay, sand, and humus. A portion of the site is also periodically submerged due to tidal action. Treatability studies were performed in conjunction with the Army Corps of Engineers Waterways Experiment Station. Studies indicated the SABRE Process could successfully treat the soil to the specified treatment goals. A full scale demonstration of the Simplot Anaerobic Biological Remediation (SABRE{trademark}) Process was carried out at the Yorktown, Virginia Naval Weaponsmore » Station. Over 650 yd{sup 3} of soil was treated to less than 2.5 mg/kg TNT in approximately 30 days. Initial concentrations were estimated to be 450 mg/kg. The soil was screened and placed into an in-ground, double-lined biocell using a soil fluidizing system.« less

The Explosion of the Display Fireworks Assembly Plant MS Vuurwerk on February 14, Culemborg, The Netherlands

DTIC Science & Technology

1992-08-01

explosion. This was demonstrated during trials performed Xn 1989 by TNO-PML as a mass explosion occurred during a bonfire test [5J. - Knfitter vulcano ...They had a height of about 25 cm and a ground diameter of 8 cm. They have all functioned properly. No- vulcano was found in its original state

An experimental study of an explosively driven flat plate launcher

NASA Astrophysics Data System (ADS)

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

2017-06-01

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

Determination of performance of non-ideal aluminized explosives.

PubMed

Keshavarz, Mohammad Hossein; Mofrad, Reza Teimuri; Poor, Karim Esmail; Shokrollahi, Arash; Zali, Abbas; Yousefi, Mohammad Hassan

2006-09-01

Non-ideal explosives can have Chapman-Jouguet (C-J) detonation pressure significantly different from those expected from existing thermodynamic computer codes, which usually allows finding the parameters of ideal detonation of individual high explosives with good accuracy. A simple method is introduced by which detonation pressure of non-ideal aluminized explosives with general formula C(a)H(b)N(c)O(d)Al(e) can be predicted only from a, b, c, d and e at any loading density without using any assumed detonation products and experimental data. Calculated detonation pressures show good agreement with experimental values with respect to computed results obtained by complicated computer code. It is shown here how loading density and atomic composition can be integrated into an empirical formula for predicting detonation pressure of proposed aluminized explosives.

Spall response of annealed copper to direct explosive loading

NASA Astrophysics Data System (ADS)

Finnegan, S. G.; Burns, M. J.; Markland, L.; Goff, M.; Ferguson, J. W.

2017-01-01

Taylor wave spall experiments were conducted on annealed copper targets using direct explosive loading. The targets were mounted on the back of an explosive disc which was being used for a shock to detonation transition (SDT) test in a gas gun. This technique allows two experiments to be conducted with one piece of explosive. Explosive loading creates a high stress state within the target with a lower strain rate than an equivalent plate impact experiment, although the shock front will also have some curvature. Three shots were performed on two differently annealed batches of copper to investigate the viability of the technique and the effect of annealing on the spall response. One pair of targets was annealed at 850°C for four hours and the other target was annealed at 600°C for one hour. The free surface velocity (FSV) profiles were recorded using a Photonic Doppler Velocimetry (PDV) probe focused on the center of the target. The profiles were compared to predictions from the CREST reactive burn model. One profile recorded a significantly lower peak velocity which was attributed to the probe being located off center. Despite this, all three calculated spall strengths closely agreed and it was concluded that the technique is a viable one for loading an inert target.

Nanotwin Formation in High-Manganese Austenitic Steels Under Explosive Shock Loading

NASA Astrophysics Data System (ADS)

Canadinc, D.; Uzer, B.; Elmadagli, M.; Guner, F.

2018-04-01

The micro-deformation mechanisms active in a high-manganese austenitic steel were investigated upon explosive shock loading. Single system of nanotwins forming within primary twins were shown to govern the deformation despite the elevated temperatures attained during testing. The benefits of nanotwin formation for potential armor materials were demonstrated.

49 CFR 174.101 - Loading Class 1 (explosive) materials.

Code of Federal Regulations, 2010 CFR

2010-10-01

... point on a small area of another box. (b) Explosive bombs, unfuzed projectiles, rocket ammunition and... large metal packages of incendiary bombs, each weighing 226 kg (500 pounds) or more, may be loaded in stock cars or in flat bottom gondola cars only if they are adequately braced. Boxed bombs, rocket...

49 CFR 176.108 - Supervision of Class 1 (explosive) materials during loading, unloading, handling and stowage.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Supervision of Class 1 (explosive) materials during loading, unloading, handling and stowage. 176.108 Section 176.108 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS...

Auxiliary Gas Loading of Explosives and Their Sensitivity to DDT (Deflagration to Detonation Transition),

DTIC Science & Technology

1984-06-25

the weight mean particle sizes were:ammonium picrate (285um), TNT (325pm), RDX (200um) and tetryl (470 and 160m). The carnauba wax (125pm) and the...WORDS (enti.e n reverse side if noceemdy and bnt, ock ,by br) PBXN103 ’"mber) Gas loading RDX Expl D PBXW-108 Sensitivity 91/9 ROX/ wax Cast H-6 PBXN...porous HE for their susceptibility to undergoing DDT. Granuiar explosives studied were RDX, waxed RDX, tetryl, TNT, and Explosive D; cast HE, TNT based

Structures to Resist the Effects of Accidental Explosions. Volume 2. Blast, Fragment, and Shock Loads

DTIC Science & Technology

1986-12-01

IS. SUPPLEMENTARY NOTfS This report is Volume II of six volumes which will eventually be published as a tri-service design manual and was sponsored by...CLASSIFICAT ION OF THIS PAGE(When Date Entered) TABLE OF CONTENTS PAGE INTRODUCTION 2-I Purpose 1 2-2 Objective 1 2 3 Background 1 2-4 Scope of Manual ...2 2-5 Format of Manual 3 VOLUME CONTENTS 2-6 General EXPLOSION EFFECTS 2-7 Effects of Explosive Output 4 BLAST LOADS 2-8 Blast Phenomena 5 2-8.1

30 CFR 36.23 - Engine intake system.

Code of Federal Regulations, 2011 CFR

2011-07-01

... suitable means for secure assembly, or shall meet the requirements for flanged metal-to-metal flame-proof... deterioration in service. It shall be so mounted in the equipment assembly that it is protected from accidental... that will arrest the propagation of an explosion and shall be so designed that improper assembly is...

30 CFR 36.23 - Engine intake system.

Code of Federal Regulations, 2010 CFR

2010-07-01

... suitable means for secure assembly, or shall meet the requirements for flanged metal-to-metal flame-proof... deterioration in service. It shall be so mounted in the equipment assembly that it is protected from accidental... that will arrest the propagation of an explosion and shall be so designed that improper assembly is...

Influence of particle size distribution on the blast pressure profile from explosives buried in saturated soils

NASA Astrophysics Data System (ADS)

Rigby, S. E.; Fay, S. D.; Tyas, A.; Clarke, S. D.; Reay, J. J.; Warren, J. A.; Gant, M.; Elgy, I.

2018-05-01

The spatial and temporal distribution of pressure and impulse from explosives buried in saturated cohesive and cohesionless soils has been measured experimentally for the first time. Ten experiments have been conducted at quarter-scale, where localised pressure loading was measured using an array of 17 Hopkinson pressure bars. The blast pressure measurements are used in conjunction with high-speed video filmed at 140,000 fps to investigate in detail the physical processes occurring at the loaded face. Two coarse cohesionless soils and one fine cohesive soil were tested: a relatively uniform sand, a well-graded sandy gravel, and a fine-grained clay. The results show that there is a single fundamental loading mechanism when explosives are detonated in saturated soil, invariant of particle size and soil cohesion. It is also shown that variability in localised loading is intrinsically linked to the particle size distribution of the surrounding soil.

Swell Sleeves for Testing Explosive Devices

NASA Technical Reports Server (NTRS)

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

2003-01-01

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

Development of a flyer design to perform plate impact shock-release-shock experiments on explosives

NASA Astrophysics Data System (ADS)

Finnegan, Simon; Ferguson, James; Millett, Jeremy; Goff, Michael

2017-06-01

A flyer design to generate a shock-release-shock loading history within a gas gun target was developed before being used to study the response of an HMX based explosive. The flyer consisted of two flyer plates separated by a vacuum gap. This created a rear free surface that, with correct material choice, allowed the target to release to close to ambient pressure between the initial shock and subsequent re-shock. The design was validated by impacting piezoelectric pin arrays to record the front flyer deformation. Shots were performed on PCTFE targets to record the shock states generated in an inert material prior to subjecting an HMX based explosive to the same loading. The response of the explosive to this loading history was recorded using magnetic particle velocity (PV) gauges embedded within the targets. The behavior during the run to detonation is compared with the response to sustained shocks at similar input pressures.

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

NASA Astrophysics Data System (ADS)

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

2013-11-01

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.

The Effect of Detonation Wave Incidence Angle on the Acceleration of Flyers by Explosives Heavily Laden with Inert Additives

NASA Astrophysics Data System (ADS)

Loiseau, Jason; Georges, William; Frost, David; Higgins, Andrew

2015-06-01

The incidence angle of a detonation wave is often assumed to weakly influence the terminal velocity of an explosively driven flyer. For explosives heavily loaded with dense additives, this may not be true due to differences in momentum and energy transfer between detonation products, additive particles, and the flyer. For tangential incidence the particles are first accelerated against the flyer via an expansion fan, whereas they are first accelerated by the detonation wave in the normal case. In the current study we evaluate the effect of normal versus tangential incidence on the acceleration of flyers by nitromethane heavily loaded with a variety of additives. Normal detonation was initiated via an explosively driven slapper. Flyer acceleration was measured with heterodyne laser interferometry (PDV). The influence of wave angle is evaluated by comparing the terminal velocity in the two cases (i.e., normal and grazing) for the heavily loaded mixtures. The decrement in flyer velocity correlated primarily with additive volume fraction and had a weak dependence on additive density or particle size. The Gurney energy of the heterogeneous explosive was observed to increase with flyer mass, presumably due to the timescale over which impinging particles could transfer momentum.

Tool and process for miniature explosive joining of tubes

NASA Technical Reports Server (NTRS)

Bement, Laurence J. (Inventor); Bailey, James W. (Inventor)

1987-01-01

A tool and process to be used in the explosive joining of tubes is disclosed. The tool consists of an initiator, a tool form, and a ribbon explosive. The assembled tool is a compact, storable, and safe device suitable for explosive joining of small, lightweight tubes down to 0.20 inch in diameter. The invention is inserted into either another tube or a tube plate. A shim or standoff between the two surfaces to be welded is necessary. Initiation of the explosive inside the tube results in a high velocity, angular collision between the mating surfaces. This collision creates surface melts and collision bonding wherein electron-sharing linkups are formed.

Characterization of Detonation Products of RSI-007 Explosive

NASA Astrophysics Data System (ADS)

Ager, Timothy; Neel, Christopher; Chhabildas, Lalit

2011-06-01

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

Characterization of detonation products of RSI-007 explosive

NASA Astrophysics Data System (ADS)

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

2012-03-01

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

Soft container for explosive nuts

NASA Technical Reports Server (NTRS)

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

1981-01-01

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.

Seismic explosive charge loader and anchor

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

Mcreynolds, O.B.

1981-07-14

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

49 CFR 174.112 - Loading Division 1.3 materials and Division 1.2 (explosive) materials (Also see § 174.101).

Code of Federal Regulations, 2012 CFR

2012-10-01

... materials and Division 1.2 (explosive) materials may not be loaded, transported or stored in a rail car equipped with any type of lighted heater or open-flame device, or in a rail car equipped with any apparatus or mechanism utilizing an internal combustion engine in its operation. (b) Except as provided in...

49 CFR 174.112 - Loading Division 1.3 materials and Division 1.2 (explosive) materials (Also see § 174.101).

Code of Federal Regulations, 2014 CFR

2014-10-01

... materials and Division 1.2 (explosive) materials may not be loaded, transported or stored in a rail car equipped with any type of lighted heater or open-flame device, or in a rail car equipped with any apparatus or mechanism utilizing an internal combustion engine in its operation. (b) Except as provided in...

49 CFR 174.112 - Loading Division 1.3 materials and Division 1.2 (explosive) materials (Also see § 174.101).

Code of Federal Regulations, 2013 CFR

2013-10-01

... materials and Division 1.2 (explosive) materials may not be loaded, transported or stored in a rail car equipped with any type of lighted heater or open-flame device, or in a rail car equipped with any apparatus or mechanism utilizing an internal combustion engine in its operation. (b) Except as provided in...

49 CFR 174.112 - Loading Division 1.3 materials and Division 1.2 (explosive) materials (Also see § 174.101).

Code of Federal Regulations, 2011 CFR

2011-10-01

... materials and Division 1.2 (explosive) materials may not be loaded, transported or stored in a rail car equipped with any type of lighted heater or open-flame device, or in a rail car equipped with any apparatus or mechanism utilizing an internal combustion engine in its operation. (b) Except as provided in...

49 CFR 174.112 - Loading Division 1.3 materials and Division 1.2 (explosive) materials (Also see § 174.101).

Code of Federal Regulations, 2010 CFR

2010-10-01

... materials and Division 1.2 (explosive) materials may not be loaded, transported or stored in a rail car equipped with any type of lighted heater or open-flame device, or in a rail car equipped with any apparatus or mechanism utilizing an internal combustion engine in its operation. (b) Except as provided in...

Shock compression and flash-heating of molecular adsorbates on the picosecond time scale

NASA Astrophysics Data System (ADS)

Berg, Christopher Michael

An ultrafast nonlinear coherent laser spectroscopy termed broadband multiplex vibrational sum-frequency generation (SFG) with nonresonant suppression was employed to monitor vibrational transitions of molecular adsorbates on metallic substrates during laser-driven shock compression and flash-heating. Adsorbates were in the form of well-ordered self-assembled monolayers (SAMs) and included molecular explosive simulants, such as nitroaromatics, and long chain-length alkanethiols. Based on reflectance measurements of the metallic substrates, femtosecond flash-heating pulses were capable of producing large-amplitude temperature jumps with DeltaT = 500 K. Laser-driven shock compression of SAMs produced pressures up to 2 GPa, where 1 GPa ≈ 1 x 104 atm. Shock pressures were estimated via comparison with frequency shifts observed in the monolayer vibrational transitions during hydrostatic pressure measurements in a SiC anvil cell. Molecular dynamics during flash-heating and shock loading were probed with vibrational SFG spectroscopy with picosecond temporal resolution and sub-nanometer spatial resolution. Flash-heating studies of 4-nitrobenzenethiolate (NBT) on Au provided insight into effects from hot-electron excitation of the molecular adsorbates at early pump-probe delay times. At longer delay times, effects from the excitation of SAM lattice modes and lower-energy NBT vibrations were shown. In addition, flash-heating studies of alkanethiolates demonstrated chain disordering behaviors as well as interface thermal conductances across the Au-SAM junction, which was of specific interest within the context of molecular electronics. Shock compression studies of molecular explosive simulants, such as 4-nitrobenzoate (NBA), demonstrated the proficiency of this technique to observe shock-induced molecular dynamics, in this case orientational dynamics, on the picosecond time scale. Results validated the utilization of these refined shock loading techniques to probe the shock initiation or first bond-breaking reactions in molecular explosives such as delta-HMX: a necessary study for the development of safer and more effective energetic materials.

Spark-safe low-voltage detonator

DOEpatents

Lieberman, Morton L.

1989-01-01

A column of explosive in a low-voltage detonator which makes it spark-safe ncludes an organic secondary explosive charge of HMX in the form of a thin pad disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to an electrical ignition device at one end of the bore. The pad of secondary charge has an axial thickness within the range of twenty to thirty percent of its diameter. The explosive column also includes a first explosive charge of CP disposed in the housing bore in the ignition region of the explosive column next to the secondary charge pad on a side opposite from the ignition device. The first CP charge is loaded under sufficient pressure, 25 to 40 kpsi, to provide mechanical confinement of the pad of secondary charge and physical coupling thereof with the ignition device. The explosive column further includes a second explosive charge of CP disposed in the housing bore in a transition region of the explosive column next to the first CP charge on a side opposite from the pad of secondary charge. The second CP charge is loaded under sufficient pressure, about 10 kpsi, to allow occurrence of DDT. The first explosive CP charge has an axial thickness within the range of twenty to thirty percent of its diameter, whereas the second explosive CP charge contains a series of increments (nominally 4) each of which has an axial thickness-to-diameter ratio of one to two.

Spark-safe low-voltage detonator

DOEpatents

Lieberman, M.L.

1988-07-01

A column of explosive in a low-voltage detonator which makes it spark-safe includes an organic secondary explosive charge of HMX in the form of a thin pad disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to an electrical ignition device at one end of the bore. The pad of secondary charge has an axial thickness within the range of twenty to thirty percent of its diameter. The explosive column also includes a first explosive charge of CP disposed in the housing bore in the ignition region of the explosive column next to the secondary charge pad on a side opposite from the ignition device. The first CP charge is loaded under sufficient pressure, 25 to 40 kpsi, to provide mechanical confinement of the pad of secondary charge and physical coupling thereof with the ignition device. The explosive column further includes a second explosive charge of CP disposed in the housing bore in a transition region of the explosive column next to the first CP charge on a side opposite from the pad of secondary charge. The second CP charge is loaded under sufficient pressure, about 10 kpsi, to allow occurrence of DDT. The first explosive CP charge has an axial thickness within the range of twenty to thirty percent of its diameter, whereas the second explosive CP charge contains a series of increments (nominally 4), each of which has an axial thickness-to-diameter ratio of one to two. 2 figs.

High speed door assembly

DOEpatents

Shapiro, Carolyn

1993-01-01

A high speed door assembly, comprising an actuator cylinder and piston rods, a pressure supply cylinder and fittings, an electrically detonated explosive bolt, a honeycomb structured door, a honeycomb structured decelerator, and a structural steel frame encasing the assembly to close over a 3 foot diameter opening within 50 milliseconds of actuation, to contain hazardous materials and vapors within a test fixture.

Experimental Study on Reaction Characteristics of PTFE/Ti/W Energetic Materials under Explosive Loading

PubMed Central

Li, Yan; Jiang, Chunlan; Wang, Zaicheng; Luo, Puguang

2016-01-01

Metal/fluoropolymer composites represent a new category of energetic structural materials that release energy through exothermic chemical reactions initiated under shock loading conditions. This paper describes an experiment designed to study the reaction characteristics of energetic materials with low porosity under explosive loading. Three PTFE (polytetrafluoroethylene)/Ti/W mixtures with different W contents are processed through pressing and sintering. An inert PTFE/W mixture without reactive Ti particles is also prepared to serve as a reference. Shock-induced chemical reactions are recorded by high-speed video through a narrow observation window. Related shock parameters are calculated based on experimental data, and differences in energy release are discussed. The results show that the reaction propagation of PTFE/Ti/W energetic materials with low porosity under explosive loading is not self-sustained. As propagation distance increases, the energy release gradually decreases. In addition, reaction failure distance in PTFE/Ti/W composites is inversely proportional to the W content. Porosity increased the failure distance due to higher shock temperature. PMID:28774056

Bonfire-safe low-voltage detonator

DOEpatents

Lieberman, M.L.

1988-07-01

A column of explosive in a low-voltage detonator which makes it bonfire-safe includes a first layer of an explosive charge of CP, or a primary explosive, and a second layer of a secondary organic explosive charge, such as PETN, which has a degradation temperature lower than the autoignition temperature of the CP or primary explosives. The first layer is composed of a pair of increments disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to and in contact with an electrical ignition device at one end of the bore. The second layer is composed of a plurality of increments disposed in the housing bore in a transition region of the explosive column next to and in contact with the first layer on a side opposite from the ignition device. The first layer is loaded under a sufficient high pressure, 25 to 40 kpsi, to achieve ignition, whereas the second layer is loaded under a sufficient low pressure, about 10 kpsi, to allow occurrence of DDT. Each increment of the first and second layers has an axial length-to-diameter ratio of one-half. 2 figs.

Bonfire-safe low-voltage detonator

DOEpatents

Lieberman, Morton L.

1990-01-01

A column of explosive in a low-voltage detonator which makes it bonfire-safe includes a first layer of an explosive charge of CP, or a primary explosive, and a second layer of a secondary organic explosive charge, such as PETN, which has a degradation temperature lower than the autoignition temperature of the CP or primary explosives. The first layer is composed of a pair of increments disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to and in contact with an electrical ignition device at one end of the bore. The second layer is composed of a plurality of increments disposed in the housing bore in a transition region of the explosive column next to and in contact with the first layer on a side opposite from the ignition device. The first layer is loaded under a sufficient high pressure, 25 to 40 kpsi, to achieve ignition, whereas the second layer is loaded under a sufficient low pressure, about 10 kpsi, to allow occurrence of DDT. Each increment of the first and second layers has an axial length-to-diameter ratio of one-half.

Explosive particle soil surface dispersion model for detonated military munitions.

PubMed

Hathaway, John E; Rishel, Jeremy P; Walsh, Marianne E; Walsh, Michael R; Taylor, Susan

2015-07-01

The accumulation of high explosive mass residue from the detonation of military munitions on training ranges is of environmental concern because of its potential to contaminate the soil, surface water, and groundwater. The US Department of Defense wants to quantify, understand, and remediate high explosive mass residue loadings that might be observed on active firing ranges. Previously, efforts using various sampling methods and techniques have resulted in limited success, due in part to the complicated dispersion pattern of the explosive particle residues upon detonation. In our efforts to simulate particle dispersal for high- and low-order explosions on hypothetical firing ranges, we use experimental particle data from detonations of munitions from a 155-mm howitzer, which are common military munitions. The mass loadings resulting from these simulations provide a previously unattained level of detail to quantify the explosive residue source-term for use in soil and water transport models. In addition, the resulting particle placements can be used to test, validate, and optimize particle sampling methods and statistical models as applied to firing ranges. Although the presented results are for a hypothetical 155-mm howitzer firing range, the method can be used for other munition types once the explosive particle characteristics are known.

30 CFR 57.6133 - Powder chests.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., operators must follow the provisions of the Institute of Makers of Explosives (IME) Safety Library... other Explosive Materials,” (May 1993), and the “Generic Loading Guide for the IME-22 Container...

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

NASA Astrophysics Data System (ADS)

Siwiński, Jarosław; Stolarski, Adam

2017-10-01

Work issues concern the safety of construction in relation to the hazards arising from explosion of the explosive charge located inside the building. The algorithms proposed in the paper for determining the parameters of the overpressure wave resulting from the detonation of clustered explosive charges, determine the basis for numerical simulation analyzes. Determination of the maximum value of peak pressure on the wave forehead of an internal explosion is presented on the basis of reflected wave analysis. Changeability in time of the internal explosion action describes the overpressure phase only. The analysis of the load caused by the internal explosive charge detonation was carried out under conditions of the undisturbed standard atmosphere. A load determination algorithm has been developed, taking into account the geometrical characteristics of the building barriers and the rooms as well as the parameters of environment in which the detonation occurs. The way of taking into account the influence of venting surfaces, i.e. windows, doors, ventilation ducts, on the overpressure wave parameters, was presented. Discloses a method to take into account the effect of the surface relief, i.e. windows, doors, air ducts, pressure wave parameters. Modification of the method for explosive overpressure determination presented by Cormie, Smith, Mays (2009), was proposed in the paper. This modification was developed on the basis of substitute impulse analysis for multiple overpressure pulses. In order to take into account the pressure distribution of explosive gases on the barrier surface, the method of modification the relationship for determination the changeability over time and space of the pressure of explosive gases, was presented. For this purpose, the changeability of the pressure wave angles of incidence to the barrier and the distance of the explosive charge to any point on the surface of the barrier, was taken into account. Based on the developed procedure, the overpressure changeability over time was determined for selected measurement points of the reference room. A comparative analysis of the determined loadings with experimental results and theoretical results of other authors, taken from the original work of Weerhiejm et al. (2012), was carried out.

Bioaccumulation kinetics of the conventional energetics TNT and RDX relative to insensitive munitions constituents DNAN and NTO in Rana pipiens tadpoles.

PubMed

Lotufo, Guilherme R; Biedenbach, James M; Sims, Jerre G; Chappell, Pornsawan; Stanley, Jacob K; Gust, Kurt A

2015-04-01

The manufacturing of explosives and their loading, assembling, and packing into munitions for use in testing on training sites or battlefields has resulted in contamination of terrestrial and aquatic sites that may pose risk to populations of sensitive species. The bioaccumulative potential of the conventional explosives 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and of the insensitive munitions (i.e., less shock sensitive) compound 2,4-dinitroanisole (DNAN) were assessed using the Northern leopard frog, Rana pipiens. Trinitrotoluene entering the organism was readily biotransformed to aminodinitrotoluenes, whereas no transformation products were measured for RDX or DNAN. Uptake clearance rates were relatively slow and similar among compounds (1.32-2.19 L kg(-1) h(-1) ). Upon transfer to uncontaminated water, elimination rate was very fast, resulting in the prediction of fast time to approach steady state (5 h or less) and short elimination half-lives (1.2 h or less). A preliminary bioconcentration factor of 0.25 L kg(-1) was determined for the insensitive munitions compound 3-nitro-1,2,4-trizole-5-one (NTO) indicating negligible bioaccumulative potential. Because of the rapid elimination rate for explosives, tadpoles inhabiting contaminated areas are expected to experience harmful effects only if under constant exposure conditions given that body burdens can rapidly depurate preventing tissue concentrations from persisting at levels that may cause detrimental biological effects. © 2014 SETAC.

Remote actuated cryocooler for superconducting generator and method of assembling the same

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

Stautner, Ernst Wolfgang; Haran, Kiruba Sivasubramaniam; Fair, Ruben Jeevanasan

2017-02-14

In one embodiment, a cryocooler assembly for cooling a heat load is provided. The cryocooler assembly includes a vacuum vessel surrounding the heat load and a cryocooler at least partially inserted into the vacuum vessel, the cryocooler including a coldhead. The assembly further includes an actuator coupled to the cryocooler. The actuator is configured to translate the cryocooler coldhead into thermal engagement with the heat load and to maintain constant pressure of the coldhead against the heat load to facilitate maintaining thermal engagement with the heat load as the heat load shrinks during a cool down process.

Minutes of the 23rd Eplosives Safety Seminar, volume 2

NASA Astrophysics Data System (ADS)

1988-08-01

Some areas of discussion at this seminar were: Hazards and risks of the disposal of chemical munitions using a cryogenic process; Special equipment for demilitarization of lethal chemical agent filled munitions; explosive containment room (ECR) repair Johnston Atoll chemical agent disposal system; Sympathetic detonation testing; Blast loads, external and internal; Structural reponse testing of walls, doors, and valves; Underground explosion effects, external airblast; Explosives shipping, transportation safety and port licensing; Explosive safety management; Underground explosion effects, model test and soil rock effects; Chemical risk and protection of workers; and Full scale explosives storage test.

High speed door assembly

DOEpatents

Shapiro, C.

1993-04-27

A high speed door assembly is described, comprising an actuator cylinder and piston rods, a pressure supply cylinder and fittings, an electrically detonated explosive bolt, a honeycomb structured door, a honeycomb structured decelerator, and a structural steel frame encasing the assembly to close over a 3 foot diameter opening within 50 milliseconds of actuation, to contain hazardous materials and vapors within a test fixture.

Shock sensing dual mode warhead

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

Shamblen, M.; Walchak, M.T.; Richmond, L.

1980-12-31

A shock sensing dual mode warhead is provided for use against both soft and hard targets and is capable of sensing which type of target has been struck. The warhead comprises a casing made of a ductile material containing an explosive charge and a fuze assembly. The ductile warhead casing will mushroom upon striking a hard target while still confining the explosive. Proper ductility and confinement are necessary for fuze shock sensing. The fuze assembly contains a pair of parallel firing trains, one initiated only by dynamic pressure caused high impact deceleration and one initiated by low impact deceleration. Themore » firing train actuated by high impact deceleration senses dynamic pressure transmitted, during deformation of the warhead, through the explosive filler which is employed as a fuzing signature. The firing train actuated by low impact deceleration contains a pyrotechnic delay to allow penetration of soft targets.« less

Printable sensors for explosive detonation

NASA Astrophysics Data System (ADS)

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

2014-10-01

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.

30 CFR 57.6902 - Excessive temperatures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... detonation, explosive material shall not be loaded into hot areas, such as kilns or sprung holes. (b) When blasting sulfide ores where hot holes occur that may react with explosive material in blastholes, operators...

30 CFR 57.6902 - Excessive temperatures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... detonation, explosive material shall not be loaded into hot areas, such as kilns or sprung holes. (b) When blasting sulfide ores where hot holes occur that may react with explosive material in blastholes, operators...

30 CFR 57.6902 - Excessive temperatures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... detonation, explosive material shall not be loaded into hot areas, such as kilns or sprung holes. (b) When blasting sulfide ores where hot holes occur that may react with explosive material in blastholes, operators...

30 CFR 57.6902 - Excessive temperatures.

Code of Federal Regulations, 2012 CFR

2012-07-01

... detonation, explosive material shall not be loaded into hot areas, such as kilns or sprung holes. (b) When blasting sulfide ores where hot holes occur that may react with explosive material in blastholes, operators...

30 CFR 57.6902 - Excessive temperatures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... detonation, explosive material shall not be loaded into hot areas, such as kilns or sprung holes. (b) When blasting sulfide ores where hot holes occur that may react with explosive material in blastholes, operators...

30 CFR 75.1318 - Loading boreholes.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) When loading boreholes drilled at an angle of 45 degrees or greater from the horizontal in solid rock... the borehole; and (2) The explosive cartridges shall be loaded in a manner that provides contact...

Ignition criterion for heterogeneous energetic materials based on hotspot size-temperature threshold

NASA Astrophysics Data System (ADS)

Barua, A.; Kim, S.; Horie, Y.; Zhou, M.

2013-02-01

A criterion for the ignition of granular explosives (GXs) and polymer-bonded explosives (PBXs) under shock and non-shock loading is developed. The formulation is based on integration of a quantification of the distributions of the sizes and locations of hotspots in loading events using a cohesive finite element method (CFEM) developed recently and the characterization by Tarver et al. [C. M. Tarver et al., "Critical conditions for impact- and shock-induced hot spots in solid explosives," J. Phys. Chem. 100, 5794-5799 (1996)] of the critical size-temperature threshold of hotspots required for chemical ignition of solid explosives. The criterion, along with the CFEM capability to quantify the thermal-mechanical behavior of GXs and PBXs, allows the critical impact velocity for ignition, time to ignition, and critical input energy at ignition to be determined as functions of material composition, microstructure, and loading conditions. The applicability of the relation between the critical input energy (E) and impact velocity of James [H. R. James, "An extension to the critical energy criterion used to predict shock initiation thresholds," Propellants, Explos., Pyrotech. 21, 8-13 (1996)] for shock loading is examined, leading to a modified interpretation, which is sensitive to microstructure and loading condition. As an application, numerical studies are undertaken to evaluate the ignition threshold of granular high melting point eXplosive, octahydro-1,3,5,7-tetranitro-1,2,3,5-tetrazocine (HMX) and HMX/Estane PBX under loading with impact velocities up to 350 ms-1 and strain rates up to 105 s-1. Results show that, for the GX, the time to criticality (tc) is strongly influenced by initial porosity, but is insensitive to grain size. Analyses also lead to a quantification of the differences between the responses of the GXs and PBXs in terms of critical impact velocity for ignition, time to ignition, and critical input energy at ignition. Since the framework permits explicit tracking of the influences of microstructure, loading, and mechanical constraints, the calculations also show the effects of stress wave reflection and confinement condition on the ignition behaviors of GXs and PBXs.

Effect of Heavy Dynamic Resistive Exercise on Acute Upper-Body Power.

ERIC Educational Resources Information Center

Hrysomallis, Con; Kidgell, Dawson

2001-01-01

Determined the influence of a heavy-load bench press on indicators of upper-body power during an explosive pushup, examining the influence of a set of 5 repetitions of 5 repetition maximum (RM) bench press preceding explosive pushups. There were no significant differences for any of the force platform data when explosive pushups were preceded by…

Investigation of explosives mechanic impact sensitivity on the samples

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

Loboyko, B.G.; Alekseev, A.V.; Litvinov, B.V.

1996-05-01

Several results of investigation into HMX-based explosive compound sensitivity to mechanic impact on the samples are presented. Mechanic loading of samples was effected by dynamic insertion of a pin. Alternation of physical state of explosive compound on account of preliminary thermal treatment or destruction of samples increased their sensitivity considerably. {copyright} {ital 1996 American Institute of Physics.}

Dual mode warhead

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

Obrsky, J.; Alexander, A.A.; Griffen, O.H.

1980-12-31

A dual mode warhead is provided for use against both soft and hard targets and capable of sensing which type of target has been struck comprising a casing made of a ductile material containing an explosive charge and a fuze assembly. The ductile warhead casing will mushroom and later split upon striking a hard target while still confining the explosive. Proper ductility and confinement are necessary for fuze sensing. The fuze assembly contains a pair of parallel firing trains, one initiated only by high and one by low impact deceleration. The firing train actuated by low impact deceleration contains amore » pyrotechnic delay to allow penetration of soft targets.« less

Explosive decomposition of a melamine-cyanuric acid supramolecular assembly for fabricating defect-rich nitrogen-doped carbon nanotubes with significantly promoted catalysis.

PubMed

Zhao, Zhongkui; Dai, Yitao; Ge, Guifang; Wang, Guiru

2015-05-26

A facile and scalable approach for fabricating structural defect-rich nitrogen-doped carbon nanotubes (MCSA-CNTs) through explosive decomposition of melamine-cyanuric acid supramolecular assembly is presented. In comparison to pristine carbon nanotubes, MCSA-CNT exhibits significantly enhanced catalytic performance in oxidant- and steam-free direct dehydrogenation of ethylbenzene, demonstrating the potential for metal-free clean and energy-saving styrene production. This finding also opens a new horizon for preparing highly-efficient carbocatalysts rich in structural defect sites for diverse transformations. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

30 CFR 7.301 - Purpose and effective date.

Code of Federal Regulations, 2010 CFR

2010-07-01

... APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Electric Motor Assemblies § 7.301 Purpose... explosion-proof electric motor assemblies intended for use in approved equipment in underground mines... requirements of this part. Those motors that incorporate features not specifically addressed in this subpart...

An Empirical Non-TNT Approach to Launch Vehicle Explosion Modeling

NASA Technical Reports Server (NTRS)

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

2015-01-01

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

The effect of detonation wave incidence angle on the acceleration of flyers by explosives heavily laden with inert additives

NASA Astrophysics Data System (ADS)

Loiseau, Jason; Georges, William; Frost, David L.; Higgins, Andrew J.

2017-01-01

The incidence angle of a detonation wave in a conventional high explosive influences the acceleration and terminal velocity of a metal flyer by increasing the magnitude of the material velocity imparted by the transmitted shock wave as the detonation is tilted towards normal loading. For non-ideal explosives heavily loaded with inert additives, the detonation velocity is typically subsonic relative to the flyer sound speed, leading to shockless accelerations when the detonation is grazing. Further, in a grazing detonation the particles are initially accelerated in the direction of the detonation and only gain velocity normal to the initial orientation of the flyer at later times due to aerodynamic drag as the detonation products expand. If the detonation wave in a non-ideal explosive instead strikes the flyer at normal incidence, a shock is transmitted into the flyer and the first interaction between the particle additives and the flyer occurs due to the imparted material velocity from the passage of the detonation wave. Consequently, the effect of incidence angle and additive properties may play a more prominent role in the flyer acceleration. In the present study we experimentally compared normal detonation loadings to grazing loadings using a 3-mm-thick aluminum slapper to impact-initiate a planar detonation wave in non-ideal explosive-particle admixtures, which subsequently accelerated a second 6.4-mm-thick flyer. Flyer acceleration was measured with heterodyne laser velocimetry (PDV). The explosive mixtures considered were packed beds of glass or steel particles of varying sizes saturated with sensitized nitromethane, and gelled nitromethane mixed with glass microballoons. Results showed that the primary parameter controlling changes in flyer velocity was the presence of a transmitted shock, with additive density and particle size playing only secondary roles. These results are similar to the grazing detonation experiments, however under normal loading the largest, higher density particles yielded the highest terminal flyer velocity, whereas in the grazing experiments the larger, low density particles yielded the highest terminal velocity.

Modeling shock responses of plastic bonded explosives using material point method

NASA Astrophysics Data System (ADS)

Shang, Hailin; Zhao, Feng; Fu, Hua

2017-01-01

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

Portable thin layer chromatography for field detection of explosives and propellants

NASA Astrophysics Data System (ADS)

Satcher, Joe H.; Maienschein, Jon L.; Pagoria, Philip F.; Racoveanu, Ana; Carman, M. Leslie; Whipple, Richard E.; Reynolds, John G.

2012-06-01

A field deployable detection kit for explosives and propellants using thin layer chromatography (TLC) has been developed at Lawrence Livermore National Laboratory (LLNL). The chemistry of the kit has been modified to allow for field detection of propellants (through propellant stabilizers), military explosives, peroxide explosives, nitrates and inorganic oxidizer precursors. For many of these target analytes, the detection limit is in the μg to pg range. A new miniaturized, bench prototype, field portable TLC (Micro TLC) kit has also been developed for the detection and identification of common military explosives. It has been demonstrated in a laboratory environment and is ready for field-testing. The kit is comprised of a low cost set of commercially available components specifically assembled for rapid identification needed in the field and identifies the common military explosives: HMX, RDX, Tetryl, Explosive D or picric acid, and TNT all on one plate. Additional modifications of the Micro TLC system have been made with fluorescent organosilicon co-polymer coatings to detect a large suite of explosives.

36. ASSEMBLY LINE AREA FROM NEAR INTERIOR LOADING DOCK. VIEW ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

36. ASSEMBLY LINE AREA FROM NEAR INTERIOR LOADING DOCK. VIEW TO WEST-NORTHWEST. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

Simulation of the Load-Unload Paths Experienced by Rock in the Vicinity of Buried Explosions.

DTIC Science & Technology

1977-12-01

Y99QAXSB04903 H2590D. 19. KEY WORDS (Continue on revere. aide if necessary end Identify by block number) Kayenta Sandstone Strain and Stress Paths Buried...These calculations are used to define loading and unloading paths in static laboratory tests on Kayenta sandstone. The data presented hsreithus...spherical explosions in an infinite medium. The material tested in the experimental program is Kayenta sandstone. 5 STRESS PATH DETERMINATION FROM FINITE

Rock Directed Breaking Under the Impulse Load

NASA Astrophysics Data System (ADS)

Khomeriki, Sergo; Mataradze, Edgar; Chikhradze, Nikoloz; Losaberidze, Marine; Khomeriki, Davit; Shatberashvili, Grigol

2016-10-01

In the work the problem of directed chipping of facing stone material by means of managing of explosion process is considered. The technology of the mining of decorative stone by the use of explosion energy means the very rapid transfer of potential energy of elastic deformations to kinetic energy. As a result, the explosion impulse, in the expanse of the inertia of rock massive, does not cause the increase of existing cracks. In the course of explosion, the shock wave is propagated by ultrasonic velocity and in this case the medium parameters (pressure, density, temperature, velocity) increase in spurts. In spite of this fact the all three conservation laws of mechanics remain valid on basis of three laws the equations are derived by which the parameters of shock wave may be defined by means of the rock physical-mechanical properties. The load on the body volume at breaking under explosion acts over very small period of the time. Therefore, stressed-deformed state of the rock was studied when the impulse load acts on the boundary. It was considered that the mining of the blocks of facing stone is performed from the hard rocks. This means that the breaking proceeds in the zone of elastic deformation. In the conditions of mentioned assumptions, the expression of the stress tensor and displacement of vector components initiated by stressed-deformed state in the rock are written.

Assessment of Head Displacement and Disassembly Force With Increasing Assembly Load at the Head/Trunnion Junction of a Total Hip Arthroplasty Prosthesis.

PubMed

Ramoutar, Darryl N; Crosnier, Emilie A; Shivji, Faiz; Miles, Anthony W; Gill, Harinderjit S

2017-05-01

Most femoral components used now for total hip arthroplasty are modular, requiring a strong connection at assembly. The aim of this study was to assess the effect of assembly force on the strength of head-trunnion interface and to measure the initial displacement of the head on the trunnion with different assembly forces. Three assembly load levels were assessed (A: 2 kN, B: 4 kN, C: 6 kN) with 4 implants in each group. The stems were mounted in a custom rig and the respective assembly loads were applied to the head at a constant rate of 0.05 kN/s (ISO7260-10:2003). Load levels were recorded during assembly. Head displacement was measured with a laser sensor. The disassembly force was determined by a standard pull-off test. The maximum head displacement on the trunnion was significantly different between the 2 kN group and the other 2 groups (4 kN, 6 kN, P = .029), but not between the 4 kN and 6 kN groups (P = .89). The disassembly forces between the 3 groups were significantly different (mean ± standard deviation, A: 1316 ± 223 kN; B: 2224 ± 151 kN; C: 3965 ± 344 kN; P = .007), with increasing assembly load leading to a higher pull-off force. For the 4 kN and 6 kN groups, a first peak of approximately 2.5 kN was observed on the load recordings during assembly before the required assembly load was eventually reached corresponding to sudden increase in head displacement to approximately 150 μm. An assembly force of 2 kN may be too low to overcome the frictional forces needed to engage the head and achieve maximum displacement on the trunnion and thus an assembly load of greater than 2.5 kN is recommended. Copyright © 2016 Elsevier Inc. All rights reserved.

Optimizing post activation potentiation for explosive activities in competitive sports

PubMed Central

Gołaś, Artur; Maszczyk, Adam; Mikołajec, Kazimierz; Stastny, Petr

2016-01-01

Abstract Post activation potentiation (PAP) has shown improved performance during movements requiring large muscular power output following contractions under near maximal load conditions. PAP can be described as an acute enhancement of performance or an enhancement of factors determining an explosive sports activity following a preload stimulus. In practice, PAP has been achieved by complex training, which involves a combination of a heavy loaded exercise followed by a biomechanically similar explosive activity, best if specific for a particular sport discipline. The main objective of this study was to investigate the effects of PAP on performance in explosive motor activities specific for basketball, luge and athletics throws. The novel approach to the experiments included individualized recovery time (IRT) between the conditioning exercise and the explosive activity. Additionally, the research groups were homogenous and included only competitive athletes of similar age and training experience. Thirty one well trained athletes from 3 different sport disciplines participated in the study. All athletes performed a heavy loaded conditioning activity (80-130%1RM) followed by a biomechanically similar explosive exercise, during which power (W) or the rate of power development (W/s/kg) was evaluated. The results of our experiment confirmed the effectiveness of PAP with well-trained athlets during explosive motor activities such as jumping, throwing and pushing. Additionally, our research showed that eccentric supramaximal intensities (130% 1RM) can be effective in eliciting PAP in strength trained athletes. Our experiments also showed that the IRT should be individualized because athletes differ in the strength level, training experience and muscle fiber structure. In the three experiments conducted with basketball players, track and field athletes and luge athletes, the optimal IRT equaled 6 min. This justifies the need to individualize the volume and intensity of the CA, and especially the IRT, between the CA and the explosive activity. PMID:28149397

Simulation Study on the Deflection Response of the 921A Steel thin plate under Explosive Impact Load

NASA Astrophysics Data System (ADS)

Zhang, Yu-Xiang; Chen, Fang; Han, Yan

2018-03-01

The Ship cabin would be subject to high-intensity shock wave load when it is attacked by anti-ship weapons, causing its side board damaged. The time course of the deflection of the thin plate made of 921A steel in different initial conditions under the impact load is researched by theoretical analysis and numerical simulation. According to the theory of elastic-plastic deformation of the thin plate, the dynamic response equation of the thin plate under the explosion impact load is established with the method of energy, and the theoretical calculation value is compared with the result from the simulation method. It proved that the theoretical calculation method has better reliability and accuracy in different boundary size.

Experimental verification of the vaporization's contribution to the shock waves generated by underwater electrical wire explosion under micro-second timescale pulsed discharge

NASA Astrophysics Data System (ADS)

Han, Ruoyu; Zhou, Haibin; Wu, Jiawei; Clayson, Thomas; Ren, Hang; Wu, Jian; Zhang, Yongmin; Qiu, Aici

2017-06-01

This paper studies pressure waves generated by exploding a copper wire in a water medium, demonstrating the significant contribution of the vaporization process to the formation of shock waves. A test platform including a pulsed current source, wire load, chamber, and diagnostic system was developed to study the shock wave and optical emission characteristics during the explosion process. In the experiment, a total of 500 J was discharged through a copper wire load 0.2 mm in diameter and 4 cm in length. A water gap was installed adjacent to the load so that the current was diverted away from the load after breakdown occurred across the water gap. This allows the electrical energy injection into the load to be interrupted at different times and at different stages of the wire explosion process. Experimental results indicate that when the load was bypassed before the beginning of the vaporization phase, the measured peak pressure was less than 2.5 MPa. By contrast, the peak pressure increased significantly to over 6.5 MPa when the water gap broke down after the beginning of the vaporization phase. It was also found that when bypassing the load after the voltage peak, similar shock waves were produced to those from a non-bypassed load. However, the total optical emission of these bypassed loads was at least an order of magnitude smaller. These results clearly demonstrate that the vaporization process is vital to the formation of shock waves and the energy deposited after the voltage collapse may only have a limited effect.

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

NASA Astrophysics Data System (ADS)

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

2017-07-01

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

Portable pallet weighing apparatus

NASA Technical Reports Server (NTRS)

Day, R. M. (Inventor)

1984-01-01

An assembly for use with several like units in weighing the mass of a loaded cargo pallet supported by its trunnions has a bridge frame for positioning the assembly on a transportation frame carrying the pallet while straddling one trunnion of the pallet and its trunnion lock, and a cradle assembly for incrementally raising the trunnion. The mass at the trunnion is carried as a static load by a slidable bracket mounted upon the bridge frame for supporting the cradle assembly. The bracket applies the static loading to an electrical load cell symmetrically positioned between the bridge frame and the bracket. The static loading compresses the load cell, causing a slight deformation and a potential difference at load cell terminals which is proportional in amplitude to the mass of the pallet at the trunnion.

The United States Army Medical Department Journal. October-December 2007

DTIC Science & Technology

2007-12-01

weapons assembly/disassembly and functions check; individual chemical, biological , radiological, nuclear and high-explosive defense; and the operation of...the 40 Army Warrior Tasks and 11 Battle Drills, to include advanced land navigation training; weapons familiarization and qualification; convoy...operations; chemical, biological , radiological, nuclear and high- explosive defense; and squad and platoon-patrol exercises in both woodland and urban

Practical small-scale explosive seam welding

NASA Technical Reports Server (NTRS)

Bement, L. J.

1983-01-01

Joining principles and variables, types of joints, capabilities, and current and potential applications are described for an explosive seam welding process developed at NASA Langley Research Center. Variable small quantities of RDX explosive in a ribbon configuration are used to create narrow (less than 0.5 inch), long length, uniform, hermetrically sealed joints that exhibit parent metal properties in a wide variety of metals, alloys, and combinations. The first major all application of the process is the repair of four nuclear reactors in Canada. Potential applications include pipelines, sealing of vessels, and assembly of large space structures.

Fuel-air munition and device

DOEpatents

Carlson, Gary A.

1976-01-01

An aerially delivered fuel-air munition consisting of an impermeable tank filled with a pressurized liquid fuel and joined at its two opposite ends with a nose section and a tail assembly respectively to complete an aerodynamic shape. On impact the tank is explosively ruptured to permit dispersal of the fuel in the form of a fuel-air cloud which is detonated after a preselected time delay by means of high explosive initiators ejected from the tail assembly. The primary component in the fuel is methylacetylene, propadiene, or mixtures thereof to which is added a small mole fraction of a relatively high vapor pressure liquid diluent or a dissolved gas diluent having a low solubility in the primary component.

Utilizing CFD for Prediction of HD1.3 Pressure Loads in a Cell with Venting

DTIC Science & Technology

2010-07-01

room. The gas load is a result of the heat released during the explosion and afterburning of explosives that was not consumed by the initial...Structural Systems Design Guide HNDED-CS-93-72 specifies that all HD 1.3 in a room will be summed and converted to an equivalent TNT mass (based on...the H2 and CO are shown in Table 5. The Pre- Afterburning quantities are based on the chemical equilibrium calculations performed in the AFCESI code

Experimental transient and permanent deformation studies of steel-sphere-impacted or explosively-impulsed aluminum panels

NASA Technical Reports Server (NTRS)

Witmer, E. A.; Merlis, F.; Rodal, J. J. A.; Stagliano, T. R.

1977-01-01

The sheet explosive loading technique (SELT) was employed to obtain elastic-plastic, large deflection 3-d transient and/or permanent strain data on simple well defined structural specimens and materials: initially-flat 6061-T651 aluminum panels with all four sides ideally clamped via integral construction. The SELT loading technique was chosen since it is both convenient and provides "forcing function information" of small uncertainty. These data will be useful for evaluating pertinent 3-d structural response prediction methods.

30 CFR 56.6307 - Drill stem loading.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Drill stem loading. 56.6307 Section 56.6307 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Drill stem loading. Explosive material shall not be loaded into blastholes with drill stem equipment or...

30 CFR 56.6307 - Drill stem loading.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Drill stem loading. 56.6307 Section 56.6307 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Drill stem loading. Explosive material shall not be loaded into blastholes with drill stem equipment or...

30 CFR 56.6307 - Drill stem loading.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Drill stem loading. 56.6307 Section 56.6307 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Drill stem loading. Explosive material shall not be loaded into blastholes with drill stem equipment or...

30 CFR 56.6307 - Drill stem loading.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Drill stem loading. 56.6307 Section 56.6307 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Drill stem loading. Explosive material shall not be loaded into blastholes with drill stem equipment or...

30 CFR 56.6307 - Drill stem loading.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drill stem loading. 56.6307 Section 56.6307 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Drill stem loading. Explosive material shall not be loaded into blastholes with drill stem equipment or...

Interpenetrated Binary Supramolecular Nanofibers for Sensitive Fluorescence Detection of Six Classes of Explosives.

PubMed

Xiong, Wei; Zhu, Qijian; Gong, Yanjun; Wang, Chen; Che, Yanke; Zhao, Jincai

2018-04-03

In this work, we develop a sequential self-assembly approach to fabricate interpenetrated binary supramolecular nanofibers consisting of carbazole oligomer 1-cobalt(II) (1-Co 2+ ) coordination nanofibers and oligomer 2 nanofibers for the sensitive detection of six classes of explosives. When exposed to peroxide explosives (e.g., H 2 O 2 ), Co 2+ in 1-Co 2+ coordination nanofibers can be reduced to Co + that can transfer an electron to the excited 2 nanofibers and thereby quench their fluorescence. On the other hand, when exposed to the other five classes of explosives, the excited 2 nanofibers can transfer an electron to explosives to quench their fluorescence. On the basis of the distinct fluorescence quenching mechanisms, six classes of explosives can be sensitively detected. Herein, we provide a new strategy to design broad-band fluorescence sensors for a rich identification of threats.

Androgynous, Reconfigurable Closed Loop Feedback Controlled Low Impact Docking System With Load Sensing Electromagnetic Capture Ring

NASA Technical Reports Server (NTRS)

Lewis, James L. (Inventor); Carroll, Monty B. (Inventor); Morales, Ray H. (Inventor); Le, Thang D. (Inventor)

2002-01-01

The present invention relates to a fully androgynous, reconfigurable closed loop feedback controlled low impact docking system with load sensing electromagnetic capture ring. The docking system of the present invention preferably comprises two Docking- assemblies, each docking assembly comprising a load sensing ring having an outer face, one of more electromagnets, one or more load cells coupled to said load sensing ring. The docking assembly further comprises a plurality of actuator arms coupled to said load sensing ring and capable of dynamically adjusting the orientation of said load sensing ring and a reconfigurable closed loop control system capable of analyzing signals originating from said plurality of load cells and of outputting real time control for each of the actuators. The docking assembly of the present invention incorporates an active load sensing system to automatically dynamically adjust the load sensing ring during capture instead of requiring significant force to push and realign the ring.

Direct Analysis in Real Time Mass Spectrometry of Potential By-Products from Homemade Nitrate Ester Explosive Synthesis

PubMed Central

Sisco, Edward; Forbes, Thomas P.

2016-01-01

This work demonstrates the coupling of direct analysis in real time (DART) ionization with time-of-flight mass spectrometry (MS) in an off-axis configuration for the trace detection and analysis of potential partially nitrated and dimerized by-products of homemade nitrate ester explosive synthesis. Five compounds relating to the synthesis of nitroglycerin (NG) and pentaerythritol tetranitrate (PETN) were examined. Deprotonated ions and adducts with molecular oxygen, nitrite, and nitrate were observed in the mass spectral responses of these compounds. A global optimum temperature of 350 °C for the by-products investigated here, enabled single nanogram to sub nanogram trace detection. Matrix effects were examined through a series of mixtures containing one or more compounds (sugar alcohol precursors, by-products, and/or explosives) across a range of mass loadings. The explosives MS responses experienced competitive ionization in the presence of all by-products. The magnitude of this influence corresponded to both the degree of by-product nitration and the relative mass loading of the by-product to the explosive. This work provides a characterization of potential by-products from homemade nitrate ester synthesis, including matrix effects and potential challenges that might arise from the trace detection of homemade explosives (HMEs) containing impurities. Detection and understanding of HME impurities and complex mixtures may provide valuable information for the screening and sourcing of homemade nitrate ester explosives. PMID:26838397

DDT Characteristics of Laser Driven Exploding Bridgewire Detonators

NASA Astrophysics Data System (ADS)

Welle, Eric

2005-07-01

The initiation and performance characteristics of Laser Exploding Bridgewire (LEBW) detonators loaded with CL-20, CP and BNCP were examined. LEBW devices, in name, as well as in function, exhibit similarities to their electrically driven counterparts with the exception that the means for energy deposition into the driving metal media results from photon absorption instead of electrical joule heating. CP and BNCP were chosen due to their well-known propensity to rapidly undergo a deflagration-to-detonation transition (DDT) and CL-20 was chosen to explore its utility as a DDT explosive. The explosive loading within the LEBW detonators were similar in nature to traditional EBW devices with regard to %TMD loading of the initial increment as well as quantity of energetic materials. Comparisons of the energy fluences required for initiation of the explosives will be discussed. Additionally, streak camera measurements will be reviewed that were conducted at what would be considered ``hard-fire'' fluence levels as well as conditions closer to the mean firing fluence levels of initiation.

Explosive Loading of Metals and Related Topics

DTIC Science & Technology

1986-05-01

Griffiths, "A U. K. Note on the History of Shaped Charges,• Royal Armament Research and Development Establishment Report, August 1983, presented...1925. 20. R. W. Wood, •optical and Physical Effects of High Explosives,• Proceedings of .the Royal Society (London), Vol. 157A, 1936, pp. 249-261...correctly analyzes geometric configurations in this report such as the Jelly Roll, the Dagwood and similar explosive-metal multilayer arrangements. In

A Manual for the Prediction of Blast and Fragment Loadings on Structures

DTIC Science & Technology

1981-08-01

H. and Amsden, A. A., "Fluid Dynamics---An Introductory 4100, Los Alamos Scientific Laboratory, University of California, New Mexico, February 1970...Navy Explosives Safety Board, "The Missile Hazard from Explosions," Technical Paper No. 2, ,December 1945 . Arvidsson, T. and Eriksson, L... Alamos Scientific Laboratory, Los Alamos , New-Mexico, June 1975. "Behavior and Utilization of Explosives in Engineering Design and Biomechda-. ical

Effect of Explosion Bulge Test Parameters on the Measurement of Deformation Resistance for Steel

DTIC Science & Technology

2014-02-01

UNCLASSIFIED UNCLASSIFIED Effect of Explosion Bulge Test Parameters on the Measurement of Deformation Resistance for Steel C...Measurement of Deformation Resistance for Steel Executive Summary The Explosion Bulge Test has been used for over 60 years as a standard test for...the assessment of steel toughness and deformation resistance under blast loading conditions [1-3]. However, details of the test conditions vary

Pulse generator with intermediate inductive storage as a lightning simulator

NASA Astrophysics Data System (ADS)

Kovalchuk, B. M.; Kharlov, A. V.; Zherlytsyn, A. A.; Kumpyak, E. V.; Tsoy, N. V.

2016-06-01

Compact transportable generators are required for simulating a lightning current pulse for electrical apparatus testing. A bi-exponential current pulse has to be formed by such a generator (with a current rise time of about two orders of magnitude faster than the damping time). The objective of this study was to develop and investigate a compact pulse generator with intermediate inductive storage and a fuse opening switch as a simulator of lightning discharge. A Marx generator (six stages) with a capacitance of 1 μF and an output voltage of 240 kV was employed as primary storage. In each of the stages, two IK-50/3 (50 kV, 3 μF) capacitors are connected in parallel. The generator inductance is 2 μH. A test bed for the investigations was assembled with this generator. The generator operates without SF6 and without oil in atmospheric air, which is very important in practice. Straight copper wires with adjustable lengths and diameters were used for the electro-explosive opening switch. Tests were made with active-inductive loads (up to 0.1 Ω and up to 6.3 μH). The current rise time is lower than 1200 ns, and the damping time can be varied from 35 to 125 μs, following the definition of standard lightning current pulse in the IEC standard. Moreover, 1D MHD calculations of the fuse explosion were carried out self-consistently with the electric circuit equations, in order to calculate more accurately the load pulse parameters. The calculations agree fairly well with the tests. On the basis of the obtained results, the design of a transportable generator was developed for a lightning simulator with current of 50 kA and a pulse shape corresponding to the IEEE standard.

CFD Applications in Support of the Space Shuttle Risk Assessment

NASA Technical Reports Server (NTRS)

Baum, Joseph D.; Mestreau, Eric; Luo, Hong; Sharov, Dmitri; Fragola, Joseph; Loehner, Rainald; Cook, Steve (Technical Monitor)

2000-01-01

The paper describes a numerical study of a potential accident scenario of the space shuttle, operating at the same flight conditions as flight 51L, the Challenger accident. The interest in performing this simulation is derived by evidence that indicates that the event itself did not exert large enough blast loading on the shuttle to break it apart. Rather, the quasi-steady aerodynamic loading on the damaged, unbalance vehicle caused the break-up. Despite the enormous explosive potential of the shuttle total fuel load (both liquid and solid), the post accident explosives working group estimated the maximum energy involvement to be equivalent to about five hundreds of pounds of TNT. This understanding motivated the simulation described here. To err on the conservative side, we modeled the event as an explosion, and used the maximum energy estimate. We modeled the transient detonation of a 500 lbs spherical charge of TNT, placed at the main engine, and the resulting blast wave propagation about the complete stack. Tracking of peak pressures and impulses at hundreds of locations on the vehicle surface indicate that the blast load was insufficient to break the vehicle, hence demonstrating likely crew survivability through such an event.

Evaluation of Blast Resistance of Fiber Reinforced Composite Specimens under Contact Blast Load

NASA Astrophysics Data System (ADS)

Janota, O.; Foglar, M.

2017-09-01

This paper presents results of experimental programme which took place in 2014, 2015 and 2016. Experiments were focused on the resistance of full scale concrete panels subjected to contact blast loading. Specimens were loaded by contact blast by plastic explosive. All specimens were reinforced concrete slabs made of fiber concrete. Basalt mesh and textile sheets were added to some of the experiments for creating more heterogeneous material to achieve better resistance of the specimens. Evaluation of experiments was mainly focused on the damaged area on the contact side and soffit of the specimens. Dependency of the final damage of concrete panels on the weight of explosive and concrete strength was assessed.

Pressure-welded flange assembly provides leaktight seal at reduced bolt loads

NASA Technical Reports Server (NTRS)

Martenson, A. J.

1966-01-01

Vibration resistant flange-connector assembly provides a leaktight seal under reduced bolt loads. The assembly consists of ductile metal plates that are pressure welded between dies mounted in recessed flanges.

Fluid blade disablement tool

DOEpatents

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

2012-01-10

A fluid blade disablement (FBD) tool that forms both a focused fluid projectile that resembles a blade, which can provide precision penetration of a barrier wall, and a broad fluid projectile that functions substantially like a hammer, which can produce general disruption of structures behind the barrier wall. Embodiments of the FBD tool comprise a container capable of holding fluid, an explosive assembly which is positioned within the container and which comprises an explosive holder and explosive, and a means for detonating. The container has a concavity on the side adjacent to the exposed surface of the explosive. The position of the concavity relative to the explosive and its construction of materials with thicknesses that facilitate inversion and/or rupture of the concavity wall enable the formation of a sharp and coherent blade of fluid advancing ahead of the detonation gases.

Self-aligning hydraulic piston assembly for tensile testing of ceramic

DOEpatents

Liu, Kenneth C.

1987-01-01

The present invention is directed to a self-aligning grip housing assembly that can transmit an uniaxial load to a tensil specimen without introducing bending stresses into the specimen. Disposed inside said grip housing assembly are a multiplicity of supporting pistons connected to a common source of pressurized oil that carry equal shares of the load applied to the specimen irregardless whether there is initial misalignment between the specimen load column assembly and housing axis.

Self-aligning hydraulic piston assembly for tensile testing of ceramic

DOEpatents

Liu, K.C.

1987-08-18

The present invention is directed to a self-aligning grip housing assembly that can transmit an uniaxial load to a tensile specimen without introducing bending stresses into the specimen. Disposed inside said grip housing assembly are a multiplicity of supporting pistons connected to a common source of pressurized oil that carry equal shares of the load applied to the specimen regardless whether there is initial misalignment between the specimen load column assembly and housing axis. 4 figs.

Viper cabin-fuselage structural design concept with engine installation and wing structural design

NASA Technical Reports Server (NTRS)

Marchesseault, B.; Carr, D.; Mccorkle, T.; Stevens, C.; Turner, D.

1993-01-01

This report describes the process and considerations in designing the cabin, nose, drive shaft, and wing assemblies for the 'Viper' concept aircraft. Interfaces of these assemblies, as well as interfaces with the sections of the aircraft aft of the cabin, are also discussed. The results of the design process are included. The goal of this project is to provide a structural design which complies with FAR 23 requirements regarding occupant safety, emergency landing loads, and maneuvering loads. The design must also address the interfaces of the various systems in the cabin, nose, and wing, including the drive shaft, venting, vacuum, electrical, fuel, and control systems. Interfaces between the cabin assembly and the wing carrythrough and empennage assemblies were required, as well. In the design of the wing assemblies, consistency with the existing cabin design was required. The major areas considered in this report are materials and construction, loading, maintenance, environmental considerations, wing assembly fatigue, and weight. The first three areas are developed separately for the nose, cabin, drive shaft, and wing assemblies, while the last three are discussed for the entire design. For each assembly, loading calculations were performed to determine the proper sizing of major load carrying components. Table 1.0 lists the resulting margins of safety for these key components, along with the types of the loads involved, and the page number upon which they are discussed.

30 CFR 56.6202 - Vehicles.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Vehicles. 56.6202 Section 56.6202 Mineral... Vehicles. (a) Vehicles containing explosive material shall be— (1) Maintained in good condition and shall... device being used in the loading operation. (b) Vehicles containing explosives shall have— (1) No...

30 CFR 56.6202 - Vehicles.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Vehicles. 56.6202 Section 56.6202 Mineral... Vehicles. (a) Vehicles containing explosive material shall be— (1) Maintained in good condition and shall... device being used in the loading operation. (b) Vehicles containing explosives shall have— (1) No...

30 CFR 56.6202 - Vehicles.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Vehicles. 56.6202 Section 56.6202 Mineral... Vehicles. (a) Vehicles containing explosive material shall be— (1) Maintained in good condition and shall... device being used in the loading operation. (b) Vehicles containing explosives shall have— (1) No...

30 CFR 56.6202 - Vehicles.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Vehicles. 56.6202 Section 56.6202 Mineral... Vehicles. (a) Vehicles containing explosive material shall be— (1) Maintained in good condition and shall... device being used in the loading operation. (b) Vehicles containing explosives shall have— (1) No...

30 CFR 56.6202 - Vehicles.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Vehicles. 56.6202 Section 56.6202 Mineral... Vehicles. (a) Vehicles containing explosive material shall be— (1) Maintained in good condition and shall... device being used in the loading operation. (b) Vehicles containing explosives shall have— (1) No...

49 CFR 176.104 - Loading and unloading Class 1 (explosive) materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... is formed by use of an open hook may not be used in handling Class 1 (explosive) materials. (e) Only... feet) long, and 10 cm (3.9 inches) thick, and be made of woven hemp, sisal, or similar fiber, or foam...

49 CFR 176.104 - Loading and unloading Class 1 (explosive) materials.

Code of Federal Regulations, 2011 CFR

2011-10-01

... is formed by use of an open hook may not be used in handling Class 1 (explosive) materials. (e) Only... feet) long, and 10 cm (3.9 inches) thick, and be made of woven hemp, sisal, or similar fiber, or foam...

49 CFR 176.104 - Loading and unloading Class 1 (explosive) materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... is formed by use of an open hook may not be used in handling Class 1 (explosive) materials. (e) Only... feet) long, and 10 cm (3.9 inches) thick, and be made of woven hemp, sisal, or similar fiber, or foam...

49 CFR 176.104 - Loading and unloading Class 1 (explosive) materials.

Code of Federal Regulations, 2010 CFR

2010-10-01

... is formed by use of an open hook may not be used in handling Class 1 (explosive) materials. (e) Only... feet) long, and 10 cm (3.9 inches) thick, and be made of woven hemp, sisal, or similar fiber, or foam...

49 CFR 176.104 - Loading and unloading Class 1 (explosive) materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... is formed by use of an open hook may not be used in handling Class 1 (explosive) materials. (e) Only... feet) long, and 10 cm (3.9 inches) thick, and be made of woven hemp, sisal, or similar fiber, or foam...

Self-locking mechanical center joint

NASA Technical Reports Server (NTRS)

Bush, H. G.; Wallsom, R. E. (Inventor)

1985-01-01

A device for connecting, rotating and locking together a pair of structural half columns is described. The device is composed of an identical pair of cylindrical hub assemblies connected at their inner faces by a spring loaded hinge; each hub assembly having a structural half column attached to its outer end. Each hub assembly has a spring loading locking ring member movably attached adjacent to its inner face and includes a latch member for holding the locking ring in a rotated position subject to the force of its spring. Each hub assembly also has a hammer member for releasing the latch on the opposing hub assembly when the hub assemblies are rotated together. The spring loaded hinge connecting the hub assemblies rotates the hub assemblies and attached structural half columns together bringing the inner faces of the opposing hub assemblies into contact with one another.

Simulations of Heterogeneous Detonations and Post Detonation Turbulent Mixing and Afterburning

NASA Astrophysics Data System (ADS)

Menon, Suresh; Gottiparthi, Kalyana

2011-06-01

Most metal-loaded explosives and thermobaric explosives exploit the afterburning of metals to maintain pressure and temperature conditions.The use of such explosives in complex environment can result in post detonation flow containing many scales of vortical motion, flow jetting and shear, as well as plume-surface interactions due to flow impingement and wall flows. In general, all these interactions can lead to highly turbulent flow fields even if the initial ambient conditions were quiescent. Thus, turbulent mixing can dominate initial mixing and impact the final afterburn. We conduct three-dimensional numerical simulations of the propagation of detonation resulting from metal-loaded (inert or reacting) explosives and analyze the afterburn process as well as the generation of multiple scales of mixing in the post detonation flow field. Impact of the detonation and post-detonation flow field on solid surface is also considered for a variety of initial conditions. Comparison with available data is carried out to demonstrate validity of the simulation method. Supported by Defense Threat Reduction Agency

Minimizing masses in explosively driven two-shockwave physics applications

NASA Astrophysics Data System (ADS)

Buttler, William; Cherne, Frank; Furlanetto, Michael; Payton, Jeremy; Stone, Joseph; Tabaka, Leonard; Vincent, Samuel

2015-06-01

We have experimentally investigated different two-shockwave high-explosives (HE) physics package designs to maximize the variability of the second shockwave peak stress, while minimizing the total HE load of the physics tool. A critical requirement is to also have a large radial diameter of the second shockwave to maintain its value as an HE driven two-shockwave drive. We have previously shown that we could vary the peak-stress of the second-shockwave with a 76 mm diameter HE lens driving different composite boosters of PBX 9501 and TNT. Here we report on our results with a 56- and 50-mm diameter HE lens driving Baritol. The results indicate that the 56-mm diameter HE lens works well, as does the Baritol, giving total HE loads of about 250 mg TNT equivalent explosives.

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

Code of Federal Regulations, 2014 CFR

2014-07-01

... possession of loaded firearms, ammunition, loaded projectile firing devices, bows and arrows, crossbows, or... ranges; or (4) Written permission has been received from the District Commander. (b) Possession of...

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

Code of Federal Regulations, 2012 CFR

2012-07-01

... possession of loaded firearms, ammunition, loaded projectile firing devices, bows and arrows, crossbows, or... ranges; or (4) Written permission has been received from the District Commander. (b) Possession of...

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

Code of Federal Regulations, 2011 CFR

2011-07-01

... possession of loaded firearms, ammunition, loaded projectile firing devices, bows and arrows, crossbows, or... ranges; or (4) Written permission has been received from the District Commander. (b) Possession of...

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

Code of Federal Regulations, 2010 CFR

2010-07-01

... possession of loaded firearms, ammunition, loaded projectile firing devices, bows and arrows, crossbows, or... ranges; or (4) Written permission has been received from the District Commander. (b) Possession of...

Shock Isolation Elements Testing for High Input Loadings. Volume II. Foam Shock Isolation Elements.

DTIC Science & Technology

SHOCK ABSORBERS ), (*GUIDED MISSILE SILOS, SHOCK ABSORBERS ), (*EXPANDED PLASTICS, (*SHOCK(MECHANICS), REDUCTION), TEST METHODS, SHOCK WAVES, STRAIN(MECHANICS), LOADS(FORCES), MATHEMATICAL MODELS, NUCLEAR EXPLOSIONS, HARDENING.

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

Code of Federal Regulations, 2013 CFR

2013-07-01

... possession of loaded firearms, ammunition, loaded projectile firing devices, bows and arrows, crossbows, or... ranges; or (4) Written permission has been received from the District Commander. (b) Possession of...

Application of NASTRAN/COSMIC in the analysis of ship structures to underwater explosion shock

NASA Technical Reports Server (NTRS)

Fallon, D. J.; Costanzo, F. A.; Handleton, R. T.; Camp, G. C.; Smith, D. C.

1987-01-01

The application of NASTRAN/COSMIC in predicting the transient motion of ship structures to underwater, non-contact explosions is discussed. Examples illustrate the finite element models, mathematical formulations of loading functions and, where available, comparisons between analytical and experimental results.

Non-Gurney Scaling of Explosives Heavily Loaded with Dense Inert Additives

NASA Astrophysics Data System (ADS)

Loiseau, Jason; Higgins, Andrew; Frost, David

2017-06-01

For most high explosives, the ability to accelerate material to some terminal velocity scales with the ratio of material-mass to charge-mass (M/C) according to the Gurney equations. Generally, the Gurney equation for planar geometry accurately predicts the terminal velocity of the driven material until the M/C ratio is reduced to roughly 0.15 or lower; at which point gasdynamic departures from the assumptions in the model result in systematic underpredictions of the material velocity. The authors conducted a series of open-face sandwich flyer plate experiments to measure the scaling of flyer terminal velocity with M/C for a heterogeneous explosive composed of a packed bed of 280 μm steel particles saturated with amine-sensitized nitromethane (90% NM, 10% diethylenetriamine). The propulsive capability of this explosive did not scale according to a modified form of the Gurney equation. Rather, propulsive efficiency increased as the flyer plate became relatively thicker. In the present study the authors have conducted further experiments using this explosive in symmetric sandwiches as well as for normally-incident detonations initiated via a slapping foil to examine how flyer terminal velocity scales with M/C for alternative geometries and loading conditions.

Fabrication of a self-assembled and flexible SERS nanosensor for explosive detection at parts-per-quadrillion levels from fingerprints.

PubMed

Liyanage, Thakshila; Rael, Ashur; Shaffer, Sidney; Zaidi, Shozaf; Goodpaster, John V; Sardar, Rajesh

2018-04-30

Apart from high sensitivity and selectivity of surface-enhanced Raman scattering (SERS)-based trace explosive detection, efficient sampling of explosive residue from real world surfaces is very important for homeland security applications. Herein, we demonstrate an entirely new SERS nanosensor fabrication approach. The SERS nanosensor was prepared by self-assembling chemically synthesized gold triangular nanoprisms (Au TNPs), which we show display strong electromagnetic field enhancements at the sharp tips and edges, onto a pressure-sensitive flexible adhesive film. Our SERS nanosensor provides excellent SERS activity (enhancement factor = ∼6.0 × 106) and limit of detection (as low as 56 parts-per-quadrillions) with high selectivity by chemometric analyses among three commonly military high explosives (TNT, RDX, and PETN). Furthermore, the SERS nanosensors present excellent reproducibility (<4.0% relative standard deviation at 1.0 μM concentration) and unprecedentedly high stability with a "shelf life" of at least 5 months. Finally, TNT and PETN were analyzed and quantified by transferring solid explosive residues from fingerprints left on solid surfaces to the SERS nanosensor. Taken together, the demonstrated sensitivity, selectivity, and reliability of the measurements as well as with the excellent shelf life of our SERS nanosensors obviate the need for complicated sample processing steps required for other analytical techniques, and thus these nanosensors have tremendous potential not only in the field of measurement science but also for homeland security applications to combat acts of terror and military threats.

Direct analysis in real time mass spectrometry of potential by-products from homemade nitrate ester explosive synthesis.

PubMed

Sisco, Edward; Forbes, Thomas P

2016-04-01

This work demonstrates the coupling of direct analysis in real time (DART) ionization with time-of-flight mass spectrometry (MS) in an off-axis configuration for the trace detection and analysis of potential partially nitrated and dimerized by-products of homemade nitrate ester explosive synthesis. Five compounds relating to the synthesis of nitroglycerin (NG) and pentaerythritol tetranitrate (PETN) were examined. Deprotonated ions and adducts with molecular oxygen, nitrite, and nitrate were observed in the mass spectral responses of these compounds. A global optimum temperature of 350 °C for the by-products investigated here enabled single nanogram to sub nanogram trace detection. Matrix effects were examined through a series of mixtures containing one or more compounds (sugar alcohol precursors, by-products, and/or explosives) across a range of mass loadings. The explosives MS responses experienced competitive ionization in the presence of all by-products. The magnitude of this influence corresponded to both the degree of by-product nitration and the relative mass loading of the by-product to the explosive. This work provides a characterization of potential by-products from homemade nitrate ester synthesis, including matrix effects and potential challenges that might arise from the trace detection of homemade explosives (HMEs) containing impurities. Detection and understanding of HME impurities and complex mixtures may provide valuable information for the screening and sourcing of homemade nitrate ester explosives. Published by Elsevier B.V.

High power s-band vacuum load

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

Neubauer, Michael; Dudas, Alan; Krasnykh, Anatoly

Through a combination of experimentation and calculation the components of a novel room temperature dry load were successfully fabricated. These components included lossy ceramic cylinders of various lengths, thicknesses, and percent of silicon carbide (SiC). The cylinders were then assembled into stainless steel compression rings by differential heating of the parts and a special fixture. Post machining of this assembly provided a means for a final weld. The ring assemblies were then measured for S-parameters, individually and in pairs using a low-cost TE10 rectangular to TE01 circular waveguide adapter specially designed to be part of the final load assembly. Matchedmore » pairs of rings were measured for assembly into the final load, and a sliding short designed and fabricated to assist in determining the desired short location in the final assembly. The plan for the project was for Muons, Inc. to produce prototype loads for long-term testing at SLAC. The STTR funds for SLAC were to upgrade and operate their test station to ensure that the loads would satisfy their requirements. Phase III was to be the sale to SLAC of loads that Muons, Inc. would manufacture. However, an alternate solution that involved a rebuild of the old loads, reduced SLAC budget projections, and a relaxed time for the replacement of all loads meant that in-house labor will be used to do the upgrade without the need for the loads developed in this project. Consequently, the project was terminated before the long term testing was initiated. However, SLAC can use the upgraded test stand to compare the long-term performance of the ones produced in this project with their rebuilt loads when they are available.« less

Nanoplasmonic imaging of latent fingerprints with explosive RDX residues.

PubMed

Peng, Tianhuan; Qin, Weiwei; Wang, Kun; Shi, Jiye; Fan, Chunhai; Li, Di

2015-09-15

Explosive detection is a critical element in preventing terrorist attacks, especially in crowded and influential areas. It is probably more important to establish the connection of explosive loading with a carrier's personal identity. In the present work, we introduce fingerprinting as physical personal identification and develop a nondestructive nanoplasmonic method for the imaging of latent fingerprints. We further integrate the nanoplasmonic response of catalytic growth of Au NPs with NADH-mediated reduction of 1,3,5-trinitro-1,3,5-triazinane (RDX) for the quantitative analysis of RDX explosive residues in latent fingerprints. This generic nanoplasmonic strategy is expected to be used in forensic investigation to distinguish terrorists that carry explosives.

Self-aligning biaxial load frame

DOEpatents

Ward, M.B.; Epstein, J.S.; Lloyd, W.R.

1994-01-18

An self-aligning biaxial loading apparatus for use in testing the strength of specimens while maintaining a constant specimen centroid during the loading operation. The self-aligning biaxial loading apparatus consists of a load frame and two load assemblies for imparting two independent perpendicular forces upon a test specimen. The constant test specimen centroid is maintained by providing elements for linear motion of the load frame relative to a fixed cross head, and by alignment and linear motion elements of one load assembly relative to the load frame. 3 figures.

Self-aligning biaxial load frame

DOEpatents

Ward, Michael B.; Epstein, Jonathan S.; Lloyd, W. Randolph

1994-01-01

An self-aligning biaxial loading apparatus for use in testing the strength of specimens while maintaining a constant specimen centroid during the loading operation. The self-aligning biaxial loading apparatus consists of a load frame and two load assemblies for imparting two independent perpendicular forces upon a test specimen. The constant test specimen centroid is maintained by providing elements for linear motion of the load frame relative to a fixed crosshead, and by alignment and linear motion elements of one load assembly relative to the load frame.

Self-assembling siloxane bilayer directly on SiO2 surface of micro-cantilevers for long-term highly repeatable sensing to trace explosives.

PubMed

Chen, Ying; Xu, Pengcheng; Li, Xinxin

2010-07-02

This paper presents a novel sensing layer modification technique for static micro-cantilever sensors that detect trace explosives by measuring specific adsorption-induced surface stress. For the first time, a method of directly modifying a siloxane sensing bilayer on an SiO(2) surface is proposed to replace the conventional self-assembled monolayers (SAMs) of thiols on Au to avoid the trouble from long-term unstable Au-S bonds. For modifying the long-term reliable sensing bilayer on the piezoresistor-integrated micro-cantilevers, a siloxane-head bottom layer is self-assembled directly on the SiO(2) cantilever surface, which is followed by grafting another explosive-sensing-group functionalized molecule layer on top of the siloxane layer. The siloxane-modified sensor has experimentally exhibited a highly resoluble response to 0.1 ppb TNT vapor. More importantly, the repeated detection results after 140 days show no obvious attenuation in sensing signal. Also observed experimentally, the specific adsorption of the siloxane sensing bilayer to TNT molecules causes a tensile surface stress on the cantilever. Herein the measured tensile surface stress is in contrast to the compressive surface stress normally measured from conventional cantilever sensors where the sensitive thiol-SAMs are modified on an Au surface. The reason for this newly observed phenomenon is discussed and preliminarily analyzed.

Fire and explosion hazards to flora and fauna from explosives.

PubMed

Merrifield, R

2000-06-30

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

Portable radiography system using a relativistic electron beam

DOEpatents

Hoeberling, Robert F.

1990-01-01

A portable radiographic generator is provided with an explosive magnetic flux compression generator producing the high voltage necessary to generate a relativistic electron beam. The relativistic electron beam is provided with target materials which generates the desired radiographic pulse. The magnetic flux compression generator may require at least two conventional explosively driven generators in series to obtain a desired output voltage of at least 1 MV. The cathode and anode configuration of the diode are selected to provide a switching action wherein a high impedance load is presented to the magnetic flux compression generator when the high voltage is being generated, and thereafter switching to a low impedance load to generate the relativistic electron beam. Magnetic flux compression generators can be explosively driven and provided in a relatively compact, portable form for use with the relativistic x-ray equipment.

Portable radiography system using a relativistic electron beam

DOEpatents

Hoeberling, R.F.

1987-09-22

A portable radiographic generator is provided with an explosive magnetic flux compression generator producing the high voltage necessary to generate a relativistic electron beam. The relativistic electron beam is provided with target materials which generates the desired radiographic pulse. The magnetic flux compression generator may require at least two conventional explosively driven generators in series to obtain a desired output voltage of at least 1 MV. The cathode and anode configuration of the diode are selected to provide a switching action wherein a high impedance load is presented to the magnetic flux compression generator when the high voltage is being generated, and thereafter switching to a low impedance load to generate the relativistic electron beam. Magnetic flux compression generators can be explosively driven and provided in a relatively compact, portable form for use with the relativistic x-ray equipment. 8 figs.

Investigation of failure to separate an Inconel 718 frangible nut

NASA Technical Reports Server (NTRS)

Hoffman, William C., III; Hohmann, Carl

1994-01-01

The 2.5-inch frangible nut is used in two places to attach the Space Shuttle Orbiter to the External Tank. It must be capable of sustaining structural loads and must also separate into two pieces upon command. Structural load capability is verified by proof loading each flight nut, while ability to separate is verified on a sample of a production lot. Production lots of frangible nuts beginning in 1987 experienced an inability to reliably separate using one of two redundant explosive boosters. The problems were identified in lot acceptance tests, and the cause of failure has been attributed to differences in the response of the Inconel 718. Subsequent tests performed on the frangible nuts resulted in design modifications to the nuts along with redesign of the explosive booster to reliably separate the frangible nut. The problem history along with the design modifications to both the explosive booster and frangible nut are discussed in this paper. Implications of this failure experience impact any pyrotechnic separation system involving fracture of materials with respect to design margin control and lot acceptance testing.

The Inglorious Death of Jumbo

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

Meade, Roger Allen

In the summer of 1944, J. Robert Oppenheimer and Los Alamos faced a crisis. An isotopic impurity in Plutonium rendered the metal unusable in a gun-assembled atomic bomb (i.e., Little Boy). Making this situation worse was a shortage of Uranium. The combination of these two problems threatened the entire wartime project. The answer to this dilemma, in part, was to develop a novel assembly method for Plutonium using the supersonic shock waves created by several tons of high explosives to compress a ball of Plutonium into a supercritical state. Since this method, implosion, was not much more than a theoreticalmore » construct, the Trinity test was devised to proof test the process. Given the speculative nature of implosion, Trinity was a gamble of sorts. If the test failed (i.e., little or no nuclear yield), the blast of the high explosives would scatter the scarce and expensive Plutonium over the surrounding desert. Since the probability of failure remained high into the early summer of 1945, some method of containing a failed nuclear explosion was needed. Jumbo was the answer.« less

Seismic Discrimination

DTIC Science & Technology

1982-09-30

Frequency-wave-number analyses of data from Nevada Test Site (NTS) shots recorded at LASA were computed in the frequency range from 0.01 to 0.05 Hz (Ref...from events in the Soviet Union at a known test site . In order to put further factual basis behind the SP spectral discriminants we used, comparisons...explosion. A catalogue of presumed explosion# in the Soviet Union away from the regular test sites was assembled. A time-domain analysis of seismograms

Verification of Disarmament or Limitation of Armaments: Instruments, Negotiations, Proposals

DTIC Science & Technology

1992-05-01

explosions and may complicate the process of detection. An even greater difficulty faced by seismologists is the ambient background of seismic "noise...suspected event would be a complex operation. It would consist of surveys of the area of the presumed nuclear explosion in order to measure ambient ...Draft Resolution to the OAS General Assembly, June 1991 and OAS Resolution "Cooperacion para la seguridad en el hemisferio. Limitacion de la

An Advanced ESTCP PELAN System for Surface and Near-surface UXO Discrimination

DTIC Science & Technology

2009-03-01

system was designed and assembled at SAIC. Test slugs representing 30mm to 105mm shells were constructed and filled with inert materials and explosives...results and system design, ESTCP decided to discontinue the effort before the prototype was constructed and demonstrated. iii TABLE OF CONTENTS...RDX and non-explosive plasticizers ) cps counts per second CW Chemical Warfare agent d-T deuterium-tritium DoD Department of Defense DOE

Sensitivity Testing of RDX/Aluminum Powdered Explosive Mixtures for the Improved Dispersed Explosives (IDX) Project

DTIC Science & Technology

1993-04-01

perpendicular to the pipe axis. During assembly, the threads are lubricated and Teflon tape is used for sealing. Aluminum witness plates (25.4 mm thick...3.3 Electrostatic Discharge ( ESD ) ................................. 7 4. INTERMEDIATE-SCALE SENSITIVITY TESTING ..................... 8 4.1 Card Gap...tests include the DWIT, friction, and electrostatic discharge ( ESD ) tests. The purpose of these tests is to enable the researcher to ensure that the

DOE explosives safety manual

NASA Astrophysics Data System (ADS)

1990-05-01

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

Eigenvalue Detonation of Combined Effects Aluminized Explosives

NASA Astrophysics Data System (ADS)

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

2007-06-01

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

30 CFR 7.99 - Critical characteristics.

Code of Federal Regulations, 2010 CFR

2010-07-01

... proper adjustments. (h) Material and dimensions of gaskets that are essential in maintaining the explosion-proof integrity of the diesel power package. (i) Dimensions and assembly of flame arresters. (j...

30 CFR 7.99 - Critical characteristics.

Code of Federal Regulations, 2011 CFR

2011-07-01

... proper adjustments. (h) Material and dimensions of gaskets that are essential in maintaining the explosion-proof integrity of the diesel power package. (i) Dimensions and assembly of flame arresters. (j...

30 CFR 7.99 - Critical characteristics.

Code of Federal Regulations, 2013 CFR

2013-07-01

... proper adjustments. (h) Material and dimensions of gaskets that are essential in maintaining the explosion-proof integrity of the diesel power package. (i) Dimensions and assembly of flame arresters. (j...

Removal of RDX, TNB, TNT, and HMX from Cornhusker Army Ammunition Plant waters using adsorption technologies. Final report

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

Fleming, E.C.; Cerar, R.; Christenson, K.

1996-04-01

The Cornhusker Army Ammunition Plant (CAAP) is located in Grand Island, NE, and occupies 11,936 acres (4,832.38 ha) in Hall County. The CAAP is classified as a load, assembly, and pack facility and was constructed in 1942 for the purpose of manufacturing bombs for World War II. Environmental impacts of explosives manufacturing were evaluated in an Installation Assessment Study that identified 58 sources of contamination by explosive compounds. The plant is currently in standby status until completion of environmental studies required for real estate transactions. The U.S. Army Engineer Waterways Experiment Station (WES) performed evaluations of adsorption and ultraviolet chemicalmore » oxidation for remediation of explosives contamination in CAAP waters. Average initial concentrations of 33.5 micrograms/l RDX, 110.8 micrograms/l TNB, 246.1 micrograms/l TNT, and 33.9 micrograms/l HMX were analyzed in the samples collected for the WES studies. Adsorption studies included evaluation of carbons, carbonaceous resins, one polymeric resin, and organophilic clays for removal of RDX, TNB, TNT, and HMX. Preliminary tests indicated that RDX, TNB, TNT, and HMX could be reduced to less than 0.2 micrograms/l most cost effectively by carbons, i.e., Calgon Filtrasorb 400 (F-400), Westates CC-601, and American Norit ROW 0.8. Isotherm evaluations verified results of the preliminary tests and indicated RDX, TNB, TNT, and HMX could be reduced below the current analytical detection limit of 0.2 micrograms/l. Regeneration tests indicated regenerated Westates CC-601 and regenerated American Norit ROW 0.8 could remove RDX, TNB, TNT, and HMX to less than 0.2 micrograms/l. Regenerated Calgon F-400 was not as effective as regenerated Westates CC-601 and regenerated American Norit ROW 0.8.« less

Practical small-scale explosive seam welding

NASA Technical Reports Server (NTRS)

Bement, L. J.

1983-01-01

A small-scale explosive seam welding process has been developed that can significantly contribute to remote metal joining operations under hazardous or inaccessible conditions, such as nuclear reactor repair and assembly of structure in space. This paper describes this explosive seam welding process in terms of joining principles, variables, types of joints created, capabilities, and applications. Very small quantities of explosive in a ribbon configuration are used to create narrow (less than 0.5 inch), long-length, uniform, hermetically sealed joints that exhibit parent metal properties in a wide variety of metals, alloys, and combinations. The practicality of this process has been demonstrated by its current acceptance, as well as its capabilities that are superior in many applications to the universally accepted joining processes, such as mechanical fasteners, fusion and resistance welding, and adhesives.

49 CFR 174.101 - Loading Class 1 (explosive) materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... in a rail car equipped with any type of lighted heater or open-flame device, or electric devices... stock cars or in flat bottom gondola cars only if they are adequately braced. Boxed bombs, rocket... be loaded in closed cars, may be loaded in open-top cars or on flatcars, provided they are protected...

49 CFR 174.101 - Loading Class 1 (explosive) materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... in a rail car equipped with any type of lighted heater or open-flame device, or electric devices... stock cars or in flat bottom gondola cars only if they are adequately braced. Boxed bombs, rocket... be loaded in closed cars, may be loaded in open-top cars or on flatcars, provided they are protected...

49 CFR 174.101 - Loading Class 1 (explosive) materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... in a rail car equipped with any type of lighted heater or open-flame device, or electric devices... stock cars or in flat bottom gondola cars only if they are adequately braced. Boxed bombs, rocket... be loaded in closed cars, may be loaded in open-top cars or on flatcars, provided they are protected...

49 CFR 174.101 - Loading Class 1 (explosive) materials.

Code of Federal Regulations, 2011 CFR

2011-10-01

... in a rail car equipped with any type of lighted heater or open-flame device, or electric devices... stock cars or in flat bottom gondola cars only if they are adequately braced. Boxed bombs, rocket... be loaded in closed cars, may be loaded in open-top cars or on flatcars, provided they are protected...

Explosive compaction of aluminum oxide modified by multiwall carbon nanotubes

NASA Astrophysics Data System (ADS)

Buzyurkin, A. E.; Kraus, E. I.; Lukyanov, Ya L.

2018-04-01

This paper presents experiments and numerical research on explosive compaction of aluminum oxide powder modified by multiwall carbon nanotubes (MWCNT) and modeling of the stress state behind the shock front at shock loading. The aim of this study was to obtain a durable low-porosity compact sample. The explosive compaction technology is used in this problem because the aluminum oxide is an extremely hard and refractory material. Therefore, its compaction by traditional methods requires special equipment and considerable expenses.

Deflagration-to-detonation characteristics of a laser exploding bridge detonator

NASA Astrophysics Data System (ADS)

Welle, E. J.; Fleming, K. J.; Marley, S. K.

2006-08-01

Evaluation of laser initiated explosive trains has been an area of extreme interest due to the safety benefits of these systems relative to traditional electro-explosive devices. A particularly important difference is these devices are inherently less electro-static discharge (ESD) sensitive relative to traditional explosive devices due to the isolation of electrical power and associated materials from the explosive interface. This paper will report work conducted at Sandia National Laboratories' Explosive Components Facility, which evaluated the initiation and deflagration-to-detonation characteristics of a Laser Driven Exploding Bridgewire detonator. This paper will report and discuss characteristics of Laser Exploding Bridgewire devices loaded with hexanitrohexaazaisowurtzitane (CL-20) and tetraammine-cis-bis-(5-nitro-2H-tetrazolato-N2) cobalt (III) perchlorate (BNCP).

Damage Detection of a Concrete Column Subject to Blast Loads Using Embedded Piezoceramic Transducers.

PubMed

Xu, Kai; Deng, Qingshan; Cai, Lujun; Ho, Siuchun; Song, Gangbing

2018-04-28

Some of the most severe structural loadings come in the form of blast loads, which may be caused by severe accidents or even terrorist activities. Most commonly after exposure to explosive forces, a structure will suffer from different degrees of damage, and even progress towards a state of collapse. Therefore, damage detection of a structure subject to explosive loads is of importance. This paper proposes a new approach to damage detection of a concrete column structure subjected to blast loads using embedded piezoceramic smart aggregates (SAs). Since the sensors are embedded in the structure, the proposed active-sensing based approach is more sensitive to internal or through cracks than surface damage. In the active sensing approach, the embedded SAs act as actuators and sensors, that can respectively generate and detect stress waves. If the stress wave propagates across a crack, the energy of the wave attenuates, and the reduction of the energy compared to the healthy baseline is indicative of a damage. With a damage index matrix constructed by signals obtained from an array of SAs, cracks caused by blast loads can be detected throughout the structure. Conventional sensing methods such as the measurement of dynamic strain and acceleration were included in the experiment. Since columns are critical elements needed to prevent structural collapse, knowledge of their integrity and damage conditions is essential for safety after exposure to blast loads. In this research, a concrete column with embedded SAs was chosen as the specimen, and a series of explosive tests were conducted on the column. Experimental results reveal that surface damages, though appear severe, cause minor changes in the damage index, and through cracks result in significant increase of the damage index, demonstrating the effectiveness of the active sensing, enabled by embedded SAs, in damage monitoring of the column under blast loads, and thus providing a reliable indication of structural integrity in the event of blast loads.

Damage Detection of a Concrete Column Subject to Blast Loads Using Embedded Piezoceramic Transducers

PubMed Central

Deng, Qingshan; Cai, Lujun; Ho, Siuchun; Song, Gangbing

2018-01-01

Some of the most severe structural loadings come in the form of blast loads, which may be caused by severe accidents or even terrorist activities. Most commonly after exposure to explosive forces, a structure will suffer from different degrees of damage, and even progress towards a state of collapse. Therefore, damage detection of a structure subject to explosive loads is of importance. This paper proposes a new approach to damage detection of a concrete column structure subjected to blast loads using embedded piezoceramic smart aggregates (SAs). Since the sensors are embedded in the structure, the proposed active-sensing based approach is more sensitive to internal or through cracks than surface damage. In the active sensing approach, the embedded SAs act as actuators and sensors, that can respectively generate and detect stress waves. If the stress wave propagates across a crack, the energy of the wave attenuates, and the reduction of the energy compared to the healthy baseline is indicative of a damage. With a damage index matrix constructed by signals obtained from an array of SAs, cracks caused by blast loads can be detected throughout the structure. Conventional sensing methods such as the measurement of dynamic strain and acceleration were included in the experiment. Since columns are critical elements needed to prevent structural collapse, knowledge of their integrity and damage conditions is essential for safety after exposure to blast loads. In this research, a concrete column with embedded SAs was chosen as the specimen, and a series of explosive tests were conducted on the column. Experimental results reveal that surface damages, though appear severe, cause minor changes in the damage index, and through cracks result in significant increase of the damage index, demonstrating the effectiveness of the active sensing, enabled by embedded SAs, in damage monitoring of the column under blast loads, and thus providing a reliable indication of structural integrity in the event of blast loads. PMID:29710807

Dynamic fatigue performance of implant-abutment assemblies with different tightening torque values.

PubMed

Xia, Dandan; Lin, Hong; Yuan, Shenpo; Bai, Wei; Zheng, Gang

2014-01-01

Implant-abutment assemblies are usually subject to long-term cyclic loading. To evaluate the dynamic fatigue performance of implant-abutment assemblies with different tightening torque values, thirty implant-abutment assemblies (Zimmer Dental, Carlsbad, CA, USA) were randomly assigned to three tightening groups (24 Ncm; 30 Ncm; 36 Ncm), each consisted of 10 implants. Five specimens from each group were unscrewed, and their reverse torque values recorded. The remaining specimens were subjected to a load between 30 N~300 N at a loading frequency of 15 Hz for 5 × 10(6) cycles. After fatigue tests, residual reverse torque values were recorded if available. In the 24 Ncm tightening group, all the implants fractured at the first outer thread of the implant after fatigue loading, with fatigue crack propagation at the fractured surface showed by SEM observation. For the 30 Ncm and 36 Ncm tightening groups, a statistical significant difference (p<0.05) between the unloaded and loaded groups was revealed. Compared with the unloaded specimens, the specimens went through fatigue loading had decreased reverse torque values. It was demonstrated that insufficient torque will lead to poor fatigue performance of dental implant-abutment assemblies and abutment screws should be tightened to the torque recommended by the manufacturer. It was also concluded that fatigue loading would lead to preload loss.

Deformation and fracture of explosion-welded Ti/Al plates: A synchrotron-based study

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

E, J. C.; Huang, J. Y.; Bie, B. X.

Here, explosion-welded Ti/Al plates are characterized with energy dispersive spectroscopy and x-ray computed tomography, and exhibit smooth, well-jointed, interface. We perform dynamic and quasi-static uniaxial tension experiments on Ti/Al with the loading direction either perpendicular or parallel to the Ti/Al interface, using a mini split Hopkinson tension bar and a material testing system in conjunction with time-resolved synchrotron x-ray imaging. X-ray imaging and strain-field mapping reveal different deformation mechanisms responsible for anisotropic bulk-scale responses, including yield strength, ductility and rate sensitivity. Deformation and fracture are achieved predominantly in Al layer for perpendicular loading, but both Ti and Al layers asmore » well as the interface play a role for parallel loading. The rate sensitivity of Ti/Al follows those of the constituent metals. For perpendicular loading, single deformation band develops in Al layer under quasi-static loading, while multiple deformation bands nucleate simultaneously under dynamic loading, leading to a higher dynamic fracture strain. For parallel loading, the interface impedes the growth of deformation and results in increased ductility of Ti/Al under quasi-static loading, while interface fracture occurs under dynamic loading due to the disparity in Poisson's contraction.« less

Deformation and fracture of explosion-welded Ti/Al plates: A synchrotron-based study

DOE PAGES

E, J. C.; Huang, J. Y.; Bie, B. X.; ...

2016-08-02

Here, explosion-welded Ti/Al plates are characterized with energy dispersive spectroscopy and x-ray computed tomography, and exhibit smooth, well-jointed, interface. We perform dynamic and quasi-static uniaxial tension experiments on Ti/Al with the loading direction either perpendicular or parallel to the Ti/Al interface, using a mini split Hopkinson tension bar and a material testing system in conjunction with time-resolved synchrotron x-ray imaging. X-ray imaging and strain-field mapping reveal different deformation mechanisms responsible for anisotropic bulk-scale responses, including yield strength, ductility and rate sensitivity. Deformation and fracture are achieved predominantly in Al layer for perpendicular loading, but both Ti and Al layers asmore » well as the interface play a role for parallel loading. The rate sensitivity of Ti/Al follows those of the constituent metals. For perpendicular loading, single deformation band develops in Al layer under quasi-static loading, while multiple deformation bands nucleate simultaneously under dynamic loading, leading to a higher dynamic fracture strain. For parallel loading, the interface impedes the growth of deformation and results in increased ductility of Ti/Al under quasi-static loading, while interface fracture occurs under dynamic loading due to the disparity in Poisson's contraction.« less

Metal explosion chambers: designing, manufacturing, application

NASA Astrophysics Data System (ADS)

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

2017-10-01

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

Improved insulin loading in poly(lactic-co-glycolic) acid (PLGA) nanoparticles upon self-assembly with lipids.

PubMed

García-Díaz, María; Foged, Camilla; Nielsen, Hanne Mørck

2015-03-30

Polymeric nanoparticles are widely investigated as drug delivery systems for oral administration. However, the hydrophobic nature of many polymers hampers effective loading of the particles with hydrophilic macromolecules such as insulin. Thus, the aim of this work was to improve the loading of insulin into poly(lactic-co-glycolic) acid (PLGA) nanoparticles by pre-assembly with amphiphilic lipids. Insulin was complexed with soybean phosphatidylcholine or sodium caprate by self-assembly and subsequently loaded into PLGA nanoparticles by using the double emulsion-solvent evaporation technique. The nanoparticles were characterized in terms of size, zeta potential, insulin encapsulation efficiency and loading capacity. Upon pre-assembly with lipids, there was an increased distribution of insulin into the organic phase of the emulsion, eventually resulting in significantly enhanced encapsulation efficiencies (90% as compared to 24% in the absence of lipids). Importantly, the insulin loading capacity was increased up to 20% by using the lipid-insulin complexes. The results further showed that a main fraction of the lipid was incorporated into the nanoparticles and remained associated to the polymer during release studies in buffers, whereas insulin was released in a non-complexed form as a burst of approximately 80% of the loaded insulin. In conclusion, the protein load in PLGA nanoparticles can be significantly increased by employing self-assembled protein-lipid complexes. Copyright © 2014 Elsevier B.V. All rights reserved.

Spool assembly support analysis

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

Norman, B.F.

1994-10-07

This document provides the wind/seismic analysis and evaluation for the pump pit spool assemblies. Hand calculations were used for the analysis. UBC, AISC, and load factors were used in this evaluation. The results show that the actual loads are under the allowable loads and all requirements are met.

Optimization of vitamins A and D3 loading in re-assembled casein micelles and effect of loading on stability of vitamin D3 during storage.

PubMed

Loewen, Anisa; Chan, Benny; Li-Chan, Eunice C Y

2018-02-01

The objectives of this study were to apply response surface methodology to optimize fat-soluble vitamin loading in re-assembled casein micelles, and to evaluate vitamin D stability of dry formulations during ambient or accelerated storage and in fortified fluid skim milk stored under refrigeration. Optimal loading of vitamin A (1.46-1.48mg/100mgcasein) was found at 9.7mM phosphate, 5.5mM citrate and 30.0mM calcium, while optimal loading of vitamin D (1.38-1.46mg/100mg casein) was found at 4.9mM phosphate, 4.0mM citrate and 26.1mM calcium. In general, more vitamin D was retained in vitamin D-re-assembled casein micelles than control powders during storage, while vitamin D loss was not different for vitamin D-re-assembled casein micelles and control fortified milks after 21days of refrigerated storage with light exposure. In conclusion, re-assembled casein micelles with high loading efficiency show promise for improving vitamin D stability during dry storage. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Next Generation Loading System for Detonators and Primers

DTIC Science & Technology

Designed , fabricated and installed next generation tooling to provide additional manufacturing capabilities for new detonators and other small...prototype munitions on automated, semi-automated and manual machines. Lead design effort, procured and installed a primary explosive Drying Oven for a pilot...facility. Designed , fabricated and installed a Primary Explosives Waste Treatment System in a pilot environmental processing facility. Designed

NSI-1 Squib adapter development and final test report for usage on space shuttle gas sampler valve/bottle assembly 3270

NASA Technical Reports Server (NTRS)

Siebel, J. E.

1983-01-01

The possibility of utilizing the NSI-1 squib in place cartridge assembly 2270 for the function of both events required for the Space Shuttle Gas Sampler Valve/Bottle Assembly 3270 was determined. Additionally, it was a requirement that the closure disk of the NSI-1 squib and explosive residue therefrom be retained from the valve cavity in so far as possible to prevent any significant particulate from scratching the valve bore and causing sample leakage following the postfire 2 event.

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

DTIC Science & Technology

2011-02-08

Emanuelli, A.M., Medina - Ramos , W., Rivera, A. and Hernandez-Rivera, S.P., Synthesis and Assembly of Short and Long Gold Nanorods for Nitroexplosives... Medina - Ramos , A.M. Chamoun-Emanuelli, O.M. Primera-Pedrozo, A. Rivera, L.F. De La Torre-Quintana, and S.P. Hernández-Rivera, “Self Assembly of Gold...Rincón, PR, Nov. 21, 2008. 60. A.M. Chamoun-Emanuelli, W. Medina - Ramos , A. Rivera, O.M. Primera-Pedrozo and S.P. Hernández-Rivera, “Self Assembly

Nonsaturable microdryer

DOEpatents

Hirschfeld, Tomas B.

1985-01-01

A nonsaturable microdryer is provided for electrolytically removing moisture from sealed containers, particularly electronic equipment. An electrode/electrolyte assembly is disposed within a channel between the interior and exterior of a sealed container. A catalytic barrier disposed between the interior of the sealed container and the electrode/electrolyte assembly prevents the build-up of explosive concentrations of hydrogen by converting back-diffusing hydrogen and oxygen back into water, which is then recycled. A semipermeable membrane disposed between the exterior of the sealed container and the electrode/electrolyte assembly allows selective removal of hydrogen and prevents intake of water.

Nonsaturable microdryer

DOEpatents

Hirschfeld, T.B.

1984-05-23

A nonsaturable microdryer is provided for electrolytically removing moisture from sealed containers, particularly electronic equipment. An electrode/electrolyte assembly is disposed within a channel between the interior and exterior of a sealed container. A catalytic barrier disposed between the interior of the sealed container and the electrode/electrolyte assembly prevents the build-up of explosive concentrations of hydrogen by converting back-diffusing hydrogen and oxygen back into water, which is then recycled. A semipermeable membrane disposed between the exterior of the sealed container and the electrode/electrolyte assembly allows selective removal of hydrogen and prevents intake of water.

Rotor blade assembly having internal loading features

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

Soloway, Daniel David

Rotor blade assemblies and wind turbines are provided. A rotor blade assembly includes a rotor blade having exterior surfaces defining a pressure side, a suction side, a leading edge and a trailing edge each extending between a tip and a root, the rotor blade defining a span and a chord, the exterior surfaces defining an interior of the rotor blade. The rotor blade assembly further includes a loading assembly, the loading assembly including a weight disposed within the interior and movable generally along the span of the rotor blade, the weight connected to a rotor blade component such that movementmore » of the weight towards the tip causes application of a force to the rotor blade component by the weight. Centrifugal force due to rotation of the rotor blade biases the weight towards the tip.« less

Stress-induced activation of decomposition of organic explosives: a simple way to understand.

PubMed

Zhang, Chaoyang

2013-01-01

We provide a very simply way to understand the stress-induced activation of decomposition of organic explosives by taking the simplest explosive molecule nitromethane (NM) as a prototype and constraining one or two NM molecules in a shell to represent the condensed phrase of NM against the stress caused by tension and compression, sliding and rotational shear, and imperfection. The results show that the stress loaded on NM molecule can always reduce the barriers of its decomposition. We think the origin of this stress-induced activation is due to the increased repulsive intra- and/or inter- molecular interaction potentials in explosives resulted from the stress, whose release is positive to accelerate the decomposition. Besides, by these models, we can understand that the explosives in gaseous state are easier to analyze than those in condensed state and the voids in condensed explosives make them more sensitive to external stimuli relative to the perfect crystals.

Lord Justice of Appeal John Fletcher Moulton and explosives production in World War I: ‘the mathematical mind triumphant’

PubMed Central

Van der Kloot, William

2014-01-01

At the end of November 1914 Lord Moulton (1844–1921) became the director of explosives production in the War Office. A 70-year-old jurist may seem an extraordinary choice, but he was an extraordinary man. He was Senior Wrangler at Cambridge, was elected to the Royal Society for research on electricity, and learned about chemistry as a barrister for dye and explosives manufacturers. He assembled an able team of administrators and chemists who designed and managed mammoth new national explosives factories. They could not make enough TNT and picric acid from obtainable precursors, so Moulton persuaded the reluctant armed services to adopt mixtures of TNT and ammonium nitrate, which enabled them to make even more than was needed. In mid-1915 they moved to the new Ministry of Munitions, where they also became responsible for fertilizers and poison gases. In 1917 they produced explosives at a higher rate than was attained in World War II. PMID:24921109

Lord Justice of Appeal John Fletcher Moulton and explosives production in World War I: 'the mathematical mind triumphant'.

PubMed

Van der Kloot, William

2014-06-20

At the end of November 1914 Lord Moulton (1844-1921) became the director of explosives production in the War Office. A 70-year-old jurist may seem an extraordinary choice, but he was an extraordinary man. He was Senior Wrangler at Cambridge, was elected to the Royal Society for research on electricity, and learned about chemistry as a barrister for dye and explosives manufacturers. He assembled an able team of administrators and chemists who designed and managed mammoth new national explosives factories. They could not make enough TNT and picric acid from obtainable precursors, so Moulton persuaded the reluctant armed services to adopt mixtures of TNT and ammonium nitrate, which enabled them to make even more than was needed. In mid-1915 they moved to the new Ministry of Munitions, where they also became responsible for fertilizers and poison gases. In 1917 they produced explosives at a higher rate than was attained in World War II.

FEM analysis of escape capsule suffered to gas explosion

NASA Astrophysics Data System (ADS)

Li, Chang-lu; Mei, Rui-bin; Li, Chang-sheng; Cai, Ban; Liu, Xiang-hua

2013-05-01

Escape capsules are new devices for underground coal mines that provide air, water, food and supplies in the event of an emergency in where miners are unable to escape. It is difficult to carry out the experiments of explosion and safety because the danger and nonrepeatability of explosion. The structure deformation and distribution of equivalent stress has been investigated under different impact pressure conditions including unimodal and bimodal loads based on the FEM and software LS-DYNA. The results show that the distribution of deformation and equivalent stress has the same trend on the same surface with the increment of explosion pressure. The deformation and stress are larger with side impact pressure compared with that of the same front impact pressure. Furthermore, the maximum equivalent stress is 246MPa and 260MPa on the front and sides of capsule with five times for national standard impact pressure 1.5MPa. Under these conditions, the deformation is less than about 9.97mm and 10.47mm, respectively. When the front impact pressure is 2.0MPa, the deformation of capsule still belongs to elasticity but the less plastic deformation occurs on the Ushape stiffening channels with the same side impact pressure. However, it is safe for capsule structure because the equivalent stress 283MPa is much less than the tensile strength. It is noted that bimodal load accelerates the capsule deformation so that it is more dangerous compared with unimodal load.

Porous Chromatographic Materials as Substrates for Preparing Synthetic Nuclear Explosion Debris Particles

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

Harvey, Scott D.; Liezers, Martin; Antolick, Kathryn C.

2013-06-13

In this study, we investigated several porous chromatographic materials as synthetic substrates for preparing surrogate nuclear explosion debris particles. The resulting synthetic debris materials are of interest for use in developing analytical methods. Eighteen metals, including some of forensic interest, were loaded onto materials by immersing them in metal solutions (556 mg/L of each metal) to fill the pores, applying gentle heat (110°C) to drive off water, and then treating them at high temperatures (up to 800°C) in air to form less soluble metal species. High-boiling-point metals were uniformly loaded on spherical controlled-pore glass to emulate early fallout, whereas low-boiling-pointmore » metals were loaded on core-shell silica to represent coated particles formed later in the nuclear fallout-formation process. Analytical studies were applied to characterize solubility, material balance, and formation of recalcitrant species. Dissolution experiments indicated loading was 1.5 to 3 times higher than expected from the pore volume alone, a result attributed to surface coating. Analysis of load solutions before and after filling the material pores revealed that most metals were passively loaded; that is, solutions filled the pores without active metal discrimination. However, niobium and tin concentrations were lower in solutions after pore filling, and were found in elevated concentrations in the final products, indicating some metals were selectively loaded. High-temperature treatments caused reduced solubility of several metal species, and loss of some metals (rhenium and tellurium) because volatile species were formed. Sample preparation reproducibility was high (the inter-batch relative standard deviation was 7.8%, and the intra-batch relative standard deviation was 0.84%) indicating that this material is suitable for use as a working standard for analytical methods development. We anticipate future standardized radionuclide-loaded materials will find use in radioanalytical methods development and/or serve as a starting material for the synthesis of more complex forms of nuclear explosion debris (e.g., Trinitite).« less

Nanopowder synthesis based on electric explosion technology

NASA Astrophysics Data System (ADS)

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

2017-10-01

A computer simulation of the bicomponent nanoparticle formation during the electric explosion of copper and nickel wires was carried out. The calculations were performed in the framework of the molecular dynamics method using many-body potentials of interatomic interaction. As a result of an electric explosion of dissimilar metal wires, bicomponent nanoparticles having different stoichiometry and a block structure can be formed. It is possible to control the process of destruction and the structure of the formed bicomponent nanoparticles by varying the distance between the wires and the loading parameters.

NDIA 2018 IM and EM Technology Symposium: Innovative Insensitive Munition Solutions for Enhanced Warfighter Effectiveness

DTIC Science & Technology

2018-04-26

decomposition of explosives, test materials and their mixtures. A DSC for each individual explosive, test material and mixture shall be run in duplicate... run in duplicate • Explosives and test materials are mixed in a 1:1 (w/w) ratio • Samples are heated at a rate of 5°C/min from room temperature to...warrants it. If a reaction occurs in ten trials, the load is reduced until there are no reactions observed in ten trials. The ESD test was run per a

Feasibility of an advanced thrust termination assembly for a solid propellant rocket motor

NASA Technical Reports Server (NTRS)

1975-01-01

A total of 68 quench tests were conducted in a vented bomb assembly (VBA). Designed to simulate full-scale motor operating conditions, this laboratory apparatus uses a 2-inch-diameter, end-burning propellant charge and an insulated disc of consolidated hydrated aluminum sulfate along with the explosive charge necessary to disperse the salt and inject it onto the burning surface. The VBA was constructed to permit variation of motor design parameters of interest; i.e., weight of salt per unit burning surface area, weight of explosive per unit weight of salt, distance from salt surface to burning surface, incidence angle of salt injection, chamber pressure, and burn time. Completely satisfactory salt quenching, without re-ignition, occurred in only two VBA tests. These were accomplished with a quench charge ratio (QCR) of 0.023 lb salt per square inch of burning surface at dispersing charge ratios (DCR) of 13 and 28 lb of salt per lb of explosive. Candidate materials for insulating salt charges from the rocket combustion environment were evaluated in firings of 5-inch-diameter, uncured end-burner motors. A pressed, alumina ceramic fiber material was selected for further evaluation and use in the final demonstration motor.

Numerical Simulation of Blast Action on Civil Structures in Urban Environment

NASA Astrophysics Data System (ADS)

Valger, Svetlana A.; Fedorova, Natalya N.; Fedorov, Alexander V.

2017-10-01

Nowadays, a lot of industrial accidents accompanied by explosions are happening throughout the world. Also, increase in the number of terrorist acts committed by means of explosions is observed. For improving safety of buildings and structures it is necessary to raise their resistance to explosive effects, as well as to be able to predict degree of potential damage upon explosive loads of various intensities. One of the principal goals in designing the structure resistant to explosive effects is to determine the dynamic response of structures to the impact of the blast wave. To this end, the transient pressure loads on the walls of the civil engineering structures are to be determined. The simulation of explosion is highly complicated, involving an explosion causing the shock wave propagation in air and then interaction with a structure. The engineering-level techniques permit one to estimate an explosive shock impact only for isolated buildings. The complexity of the building, the presence of nearby structures and the surrounding environment cannot be taken into account. Advanced computer aid engineering (CAE) software techniques combined with the latest methods of discrete three-dimensional city modelling permits one to simulate and analyse the effects of explosions in urban areas with a precision which previously was not possible. In the paper, the simulation results are presented of shock wave forming due to a spherical explosive charge and its propagation in the vicinity of geometrical configuration imitating an urban environment. The numerical simulation of a flow in the vicinity of prisms of different cross-sections and heights located on a flat plate was performed. The calculations are carried out in a three-dimensional non-viscous formulation using ANSYS software. On a basis of simulation results, a complex wave structures were analysed, and all the peculiarities of flows and pressure history records on building walls were described and explained. The possibility of a correct description of the non-stationary wave flow in the vicinity of the complex of obstacles is demonstrated. The results are compared with the experimental data on the pressure distribution in gauges located on the prism walls. The estimation of shock wave exposure intensity was performed to different objects.

Numerical study of blast characteristics from detonation of homogeneous explosives

NASA Astrophysics Data System (ADS)

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

2010-04-01

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

5. LOOKING NORTH TOWARD BARRICADES AROUND BUILDING NO. 230, PRIMER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. LOOKING NORTH TOWARD BARRICADES AROUND BUILDING NO. 230, PRIMER AND DETONATOR LOADING BUILDING. BARRICADES DIRECT FORCE OF BLAST UPWARD IN THE EVENT OF AN EXPLOSION. - Picatinny Arsenal, 200 Area, Shell Component Loading, State Route 15 near I-80, Dover, Morris County, NJ

Modular container assembled from fiber reinforced thermoplastic sandwich panels

DOEpatents

Donnelly, Mathew William; Kasoff, William Andrew; Mcculloch, Patrick Carl; Williams, Frederick Truman

2007-12-25

An improved, load bearing, modular design container structure assembled from thermoformed FRTP sandwich panels in which is utilized the unique core-skin edge configuration of the present invention in consideration of improved load bearing performance, improved useful load volume, reduced manufacturing costs, structural weight savings, impact and damage tolerance and repair and replace issues.

Nuclear reactor removable radial shielding assembly having a self-bowing feature

DOEpatents

Pennell, William E.; Kalinowski, Joseph E.; Waldby, Robert N.; Rylatt, John A.; Swenson, Daniel V.

1978-01-01

A removable radial shielding assembly for use in the periphery of the core of a liquid-metal-cooled fast-breeder reactor, for closing interassembly gaps in the reactor core assembly load plane prior to reactor criticality and power operation to prevent positive reactivity insertion. The assembly has a lower nozzle portion for inserting into the core support and a flexible heat-sensitive bimetallic central spine surrounded by blocks of shielding material. At refueling temperature and below the spine is relaxed and in a vertical position so that the tolerances permitted by the interassembly gaps allow removal and replacement of the various reactor core assemblies. During an increase in reactor temperature from refueling to hot standby, the bimetallic spine expands, bowing the assembly toward the core center line, exerting a radially inward gap-closing-force on the above core load plane of the reactor core assembly, closing load plane interassembly gaps throughout the core prior to startup and preventing positive reactivity insertion.

Towards an Electronic Dog Nose: Surface Plasmon Resonance Immunosensor for Security and Safety

PubMed Central

Onodera, Takeshi; Toko, Kiyoshi

2014-01-01

This review describes an “electronic dog nose” based on a surface plasmon resonance (SPR) sensor and an antigen–antibody interaction for security and safety. We have concentrated on developing appropriate sensor surfaces for the SPR sensor for practical use. The review covers different surface fabrications, which all include variations of a self-assembled monolayer containing oligo(ethylene glycol), dendrimer, and hydrophilic polymer. We have carried out detection of explosives using the sensor surfaces. For the SPR sensor to detect explosives, the vapor or particles of the target substances have to be dissolved in a liquid. Therefore, we also review the development of sampling processes for explosives, and a protocol for the measurement of explosives on the SPR sensor in the field. Additionally, sensing elements, which have the potential to be applied for the electronic dog nose, are described. PMID:25198004

Track-train dynamic analysis and test program, truck static test

NASA Technical Reports Server (NTRS)

Nemes, A. G.

1974-01-01

A series of tests were conducted to define the characteristics of an ASF 11 Ride Truck Assembly including joint slop, friction and stiffness. Loading to the truck assembly included vertical load to simulate the car/pool loading combined with lateral or moment loading that resulted in desired truck deflections for the various phases of testing. All seven test conditions were successfully completed with load and deflection data being collected. No attempt is made to reduce the applicable data other than to provide computer plots.

30 CFR 57.6602 - Static electricity dissipation during loading.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Static electricity dissipation during loading... MINES Explosives Extraneous Electricity-Surface and Underground § 57.6602 Static electricity dissipation... generates a static electricity hazard— (a) An evaluation of the potential static electricity hazard shall be...

30 CFR 57.6602 - Static electricity dissipation during loading.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Static electricity dissipation during loading... MINES Explosives Extraneous Electricity-Surface and Underground § 57.6602 Static electricity dissipation... generates a static electricity hazard— (a) An evaluation of the potential static electricity hazard shall be...

30 CFR 57.6602 - Static electricity dissipation during loading.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Static electricity dissipation during loading... MINES Explosives Extraneous Electricity-Surface and Underground § 57.6602 Static electricity dissipation... generates a static electricity hazard— (a) An evaluation of the potential static electricity hazard shall be...

30 CFR 57.6602 - Static electricity dissipation during loading.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Static electricity dissipation during loading... MINES Explosives Extraneous Electricity-Surface and Underground § 57.6602 Static electricity dissipation... generates a static electricity hazard— (a) An evaluation of the potential static electricity hazard shall be...

30 CFR 57.6602 - Static electricity dissipation during loading.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Static electricity dissipation during loading... MINES Explosives Extraneous Electricity-Surface and Underground § 57.6602 Static electricity dissipation... generates a static electricity hazard— (a) An evaluation of the potential static electricity hazard shall be...

Solid state gas sensors for detection of explosives and explosive precursors

NASA Astrophysics Data System (ADS)

Chu, Yun

The increased number of terrorist attacks using improvised explosive devices (IEDs) over the past few years has made the trace detection of explosives a priority for the Department of Homeland Security. Considerable advances in early detection of trace explosives employing spectroscopic detection systems and other sensing devices have been made and have demonstrated outstanding performance. However, modern IEDs are not easily detectable by conventional methods and terrorists have adapted to avoid using metallic or nitro groups in the manufacturing of IEDs. Instead, more powerful but smaller compounds, such as TATP are being more frequently used. In addition, conventional detection techniques usually require large capital investment, labor costs and energy input and are incapable of real-time identification, limiting their application. Thus, a low cost detection system which is capable of continuous online monitoring in a passive mode is needed for explosive detection. In this dissertation, a thermodynamic based thin film gas sensor which can reliably detect various explosive compounds was developed and demonstrated. The principle of the sensors is based on measuring the heat effect associated with the catalytic decomposition of explosive compounds present in the vapor phase. The decomposition mechanism is complicated and not well known, but it can be affected by many parameters including catalyst, reaction temperature and humidity. Explosives that have relatively high vapor pressure and readily sublime at room temperature, like TATP and 2, 6-DNT, are ideal candidate for vapor phase detection using the thermodynamic gas sensor. ZnO, W2O 3, V2O5 and SnO2 were employed as catalysts. This sensor exhibited promising sensitivity results for TATP, but poor selectivity among peroxide based compounds. In order to improve the sensitivity and selectivity of the thermodynamic sensor, a Pd:SnO2 nanocomposite was fabricated and tested as part of this dissertation. A combinatorial chemistry techniques were used for catalyst discovery. Specially, a series of tin oxide catalysts with continuous varying composition of palladium were fabricated to screen for the optimum Pd loading to maximize specificity. Experimental results suggested that sensors with a 12 wt.% palladium loading generated the highest sensitivity while a 8 wt.% palladium loading provided greatest selectivity. XPS and XRD were used to study how palladium doping level affects the oxidation state and crystal structure of the nanocomposite catalyst. As with any passive detection system, a necessary theme of this dissertation was the mitigation of false positive. Toward this end, an orthogonal detection system comprised of two independent sensing platforms sharing one catalyst was demonstrated using TATP, 2, 6-DNT and ammonium nitrate as target molecules. The orthogonal sensor incorporated a thermodynamic based sensing platform to measure the heat effect associated with the decomposition of explosive molecules, and a conductometric sensing platform that monitors the change in electrical conductivity of the same catalyst when exposed to the explosive substances. Results indicate that the orthogonal sensor generates an effective response to explosives presented at part per billion level. In addition, with two independent sensing platforms, a built-in redundancy of results could be expected to minimize false positive.

Effects of combustibles on internal quasi-static loads

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

Sandoval, N.R.; Hokanson, J.C.; Esparza, E.D.

1984-08-01

The phenomenon of quasi-static pressure enhancement produced when combustible materials are placed near HE sources has been recently discovered. The effects of placing solid and liquid combustible materials near detonating explosives on internal blast loading was measured during tests conducted in a one-eighth scale model of a containment structure. In many cases, dramatic increases in gas pressures resulted. Principal conclusions of this study are: combustible materials near explosives can markedly increase gas pressures in enclosed structures; there is a lack of data on HE-combustible combinations; quasi-static loading calculations should include estimates of contributions from the burning of combustible materials whenevermore » such materials are expected to be in intimate contact with HE sources; and effects of combustibles should be investigated further to determine methods for prediction. Variations in charge to combustible mass, charge type, structure volume, degree of venting and degree of contact between HE and combustible sbould be studied.« less

ASSEMBLY TRANSFER SYSTEM DESCRIPTION DOCUMENT

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

B. Gorpani

2000-06-26

The Assembly Transfer System (ATS) receives, cools, and opens rail and truck transportation casks from the Carrier/Cask Handling System (CCHS). The system unloads transportation casks consisting of bare Spent Nuclear Fuel (SNF) assemblies, single element canisters, and Dual Purpose Canisters (DPCs). For casks containing DPCs, the system opens the DPCs and unloads the SNF. The system stages the assemblies, transfer assemblies to and from fuel-blending inventory pools, loads them into Disposal Containers (DCs), temporarily seals and inerts the DC, decontaminates the DC and transfers it to the Disposal Container Handling System. The system also prepares empty casks and DPCs formore » off-site shipment. Two identical Assembly Transfer System lines are provided in the Waste Handling Building (WHB). Each line operates independently to handle the waste transfer throughput and to support maintenance operations. Each system line primarily consists of wet and dry handling areas. The wet handling area includes a cask transport system, cask and DPC preparation system, and a wet assembly handling system. The basket transport system forms the transition between the wet and dry handling areas. The dry handling area includes the dry assembly handling system, assembly drying system, DC preparation system, and DC transport system. Both the wet and dry handling areas are controlled by the control and tracking system. The system operating sequence begins with moving transportation casks to the cask preparation area. The cask preparation operations consist of cask cavity gas sampling, cask venting, cask cool-down, outer lid removal, and inner shield plug lifting fixture attachment. Casks containing bare SNF (no DPC) are filled with water and placed in the cask unloading pool. The inner shield plugs are removed underwater. For casks containing a DPC, the cask lid(s) is removed, and the DPC is penetrated, sampled, vented, and cooled. A DPC lifting fixture is attached and the cask is placed into the cask unloading pool. In the cask unloading pool the DPC is removed from the cask and placed in an overpack and the DPC lid is severed and removed. Assemblies are removed from either an open cask or DPC and loaded into assembly baskets positioned in the basket staging rack in the assembly unloading pool. A method called ''blending'' is utilized to load DCs with a heat output of less than 11.8 kW. This involves combining hotter and cooler assemblies from different baskets. Blending requires storing some of the hotter fuel assemblies in fuel-blending inventory pools until cooler assemblies are available. The assembly baskets are then transferred from the basket staging rack to the assembly handling cell and loaded into the assembly drying vessels. After drying, the assemblies are removed from the assembly drying vessels and loaded into a DC positioned below the DC load port. After installation of a DC inner lid and temporary sealing device, the DC is transferred to the DC decontamination cell where the top area of the DC, the DC lifting collar, and the DC inner lid and temporary sealing device are decontaminated, and the DC is evacuated and backfilled with inert gas to prevent prolonged clad exposure to air. The DC is then transferred to the Disposal Container Handling System for lid welding. In another cask preparation and decontamination area, lids are replaced on the empty transportation casks and DPC overpacks, the casks and DPC overpacks are decontaminated, inspected, and transferred to the Carrier/Cask Handling System for shipment off-site. All system equipment is designed to facilitate manual or remote operation, decontamination, and maintenance. The system interfaces with the Carrier/Cask Handling System for incoming and outgoing transportation casks and DPCs. The system also interfaces with the Disposal Container Handling System, which prepares the DC for loading and subsequently seals the loaded DC. The system support interfaces are the Waste Handling Building System and other internal WHB support systems.« less

49 CFR 174.114 - Record to be made of change of seals on “Cars loaded with Division 1.1 or 1.2 (explosive...

Code of Federal Regulations, 2010 CFR

2010-10-01

... car to its destination: RailroadPlaceDate Car InitialsCar NumberNumber or description of seal broken Number or description of seal used to reseal car Reasons for opening car Condition of load Name and...

49 CFR 174.102 - Forbidden mixed loading and storage.

Code of Federal Regulations, 2014 CFR

2014-10-01

... same rail car. Additionally, they may not be transported or loaded in the same rail car or stored on carrier property with charged electric storage batteries or with any hazardous material for which a... (explosive) materials or any other material in a placarded and certified car containing a shipment of...

49 CFR 174.102 - Forbidden mixed loading and storage.

Code of Federal Regulations, 2012 CFR

2012-10-01

... same rail car. Additionally, they may not be transported or loaded in the same rail car or stored on carrier property with charged electric storage batteries or with any hazardous material for which a... (explosive) materials or any other material in a placarded and certified car containing a shipment of...

49 CFR 174.102 - Forbidden mixed loading and storage.

Code of Federal Regulations, 2013 CFR

2013-10-01

... same rail car. Additionally, they may not be transported or loaded in the same rail car or stored on carrier property with charged electric storage batteries or with any hazardous material for which a... (explosive) materials or any other material in a placarded and certified car containing a shipment of...

30 CFR 75.815 - Disconnect devices.

Code of Federal Regulations, 2011 CFR

2011-07-01

... phase-to-phase voltage of the circuit in which they are installed, and for the full-load current of the... explosion-proof enclosures, must be capable of interrupting the full-load current of the circuit or designed and installed to cause the current to be interrupted automatically prior to the opening of the...

30 CFR 75.815 - Disconnect devices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... phase-to-phase voltage of the circuit in which they are installed, and for the full-load current of the... explosion-proof enclosures, must be capable of interrupting the full-load current of the circuit or designed and installed to cause the current to be interrupted automatically prior to the opening of the...

49 CFR 172.400a - Exceptions from labeling.

Code of Federal Regulations, 2014 CFR

2014-10-01

... this subchapter). (2) A package or unit of military explosives (including ammunition) shipped by or on behalf of the DOD when in— (i) Freight containerload, carload or truckload shipments, if loaded and... cylinder permanently mounted in or on a transport vehicle. (5) A freight container, aircraft unit load...

49 CFR 172.400a - Exceptions from labeling.

Code of Federal Regulations, 2013 CFR

2013-10-01

... this subchapter). (2) A package or unit of military explosives (including ammunition) shipped by or on behalf of the DOD when in— (i) Freight containerload, carload or truckload shipments, if loaded and... cylinder permanently mounted in or on a transport vehicle. (5) A freight container, aircraft unit load...

49 CFR 172.400a - Exceptions from labeling.

Code of Federal Regulations, 2012 CFR

2012-10-01

... this subchapter). (2) A package or unit of military explosives (including ammunition) shipped by or on behalf of the DOD when in— (i) Freight containerload, carload or truckload shipments, if loaded and... cylinder permanently mounted in or on a transport vehicle. (5) A freight container, aircraft unit load...

49 CFR 174.102 - Forbidden mixed loading and storage.

Code of Federal Regulations, 2010 CFR

2010-10-01

... same rail car. Additionally, they may not be transported or loaded in the same rail car or stored on carrier property with charged electric storage batteries or with any hazardous material for which a... (explosive) materials or any other material in a placarded and certified car containing a shipment of...

49 CFR 174.102 - Forbidden mixed loading and storage.

Code of Federal Regulations, 2011 CFR

2011-10-01

... same rail car. Additionally, they may not be transported or loaded in the same rail car or stored on carrier property with charged electric storage batteries or with any hazardous material for which a... (explosive) materials or any other material in a placarded and certified car containing a shipment of...

Simulations of multi-component explosives using simplified geometric arrangements of their constituents

NASA Astrophysics Data System (ADS)

Butler, George; Pemberton, Steven

2017-06-01

Modeling and simulation is extremely important in the design and formulation of new explosives and explosive devices due to the high cost of experiment-based development. However, the efficacy of simulations depends on the accuracy of the equations of state (EOS) and reactive burn models used to characterize the energetic materials. We investigate the possibility of using the components of an explosive fill as discrete elements in a simulation, based on the relative amounts of the constituents. This is accomplished by assembling a mosaic, or ``checkerboard'', in which each cell comprises the relative amounts of the constituents as in the mixture; it is assumed that each constituent has a well-defined set of simulation parameters. We do not consider the underlying microstructure, and recognize there will be limitations to the usefulness of this technique. We are interested in determining whether there are applications for this technique that might prove useful. As a test of the concept, two binary explosives were considered. We considered shapes for a periodic cellular structure and compared results from the checkerboards with those of the baseline explosives; detonation rates, cylinder expansion, and gap test predictions were compared.

The propulsive capability of explosives heavily loaded with inert materials

NASA Astrophysics Data System (ADS)

Loiseau, J.; Georges, W.; Frost, D. L.; Higgins, A. J.

2018-01-01

The effect of inert dilution on the accelerating ability of high explosives for both grazing and normal detonations was studied. The explosives considered were: (1) neat, amine-sensitized nitromethane (NM), (2) packed beds of glass, steel, or tungsten particles saturated with amine-sensitized NM, (3) NM gelled with PMMA containing dispersed glass microballoons, (4) NM gelled with PMMA containing glass microballoons and steel particles, and (5) C-4 containing varying mass fractions of glass or steel particles. Flyer velocity was measured via photonic Doppler velocimetry, and the results were analysed using a Gurney model augmented to include the influence of the diluent. Reduction in accelerating ability with increasing dilution for the amine-sensitized NM, gelled NM, and C-4 was measured experimentally. Variation of flyer terminal velocity with the ratio of flyer mass to charge mass (M/C) was measured for both grazing and normally incident detonations in gelled NM containing 10% microballoons by mass and for steel beads saturated with amine-sensitized NM. Finally, flyer velocity was measured in grazing versus normal loading for a number of explosive admixtures. The augmented Gurney model predicted the effect of dilution on accelerating ability and the scaling of flyer velocity with M/C for mixtures containing low-density diluents. The augmented Gurney model failed to predict the scaling of flyer velocity with M/C for mixtures heavily loaded with dense diluents. In all cases, normally incident detonations propelled flyers to higher velocity than the equivalent grazing detonations because of material velocity imparted by the incident shock wave and momentum/energy transfer from the slapper used to uniformly initiate the charge.

The propulsive capability of explosives heavily loaded with inert materials

NASA Astrophysics Data System (ADS)

Loiseau, J.; Georges, W.; Frost, D. L.; Higgins, A. J.

2018-07-01

The effect of inert dilution on the accelerating ability of high explosives for both grazing and normal detonations was studied. The explosives considered were: (1) neat, amine-sensitized nitromethane (NM), (2) packed beds of glass, steel, or tungsten particles saturated with amine-sensitized NM, (3) NM gelled with PMMA containing dispersed glass microballoons, (4) NM gelled with PMMA containing glass microballoons and steel particles, and (5) C-4 containing varying mass fractions of glass or steel particles. Flyer velocity was measured via photonic Doppler velocimetry, and the results were analysed using a Gurney model augmented to include the influence of the diluent. Reduction in accelerating ability with increasing dilution for the amine-sensitized NM, gelled NM, and C-4 was measured experimentally. Variation of flyer terminal velocity with the ratio of flyer mass to charge mass ( M/ C) was measured for both grazing and normally incident detonations in gelled NM containing 10% microballoons by mass and for steel beads saturated with amine-sensitized NM. Finally, flyer velocity was measured in grazing versus normal loading for a number of explosive admixtures. The augmented Gurney model predicted the effect of dilution on accelerating ability and the scaling of flyer velocity with M/ C for mixtures containing low-density diluents. The augmented Gurney model failed to predict the scaling of flyer velocity with M/ C for mixtures heavily loaded with dense diluents. In all cases, normally incident detonations propelled flyers to higher velocity than the equivalent grazing detonations because of material velocity imparted by the incident shock wave and momentum/energy transfer from the slapper used to uniformly initiate the charge.

Explosive-driven, high speed, arcless switch

DOEpatents

Skogmo, P.J.; Tucker, T.J.

1986-05-02

An explosive-actuated, fast-acting arcless switch contains a highly conductive foil to carry high currents positioned adjacent a dielectric surface within a casing. At one side of the foil opposite the dielectric surface is an explosive which, when detonated, drives the conductive foil against the dielectric surface. A pattern of grooves in the dielectric surface ruptures the foil to establish a rupture path having a pattern corresponding to the pattern of the grooves. The impedance of the ruptured foil is greater than that of the original foil to divert high current to a load. Planar and cylindrical embodiments of the switch are disclosed.

Explosive-driven, high speed, arcless switch

DOEpatents

Skogmo, Phillip J.; Tucker, Tillman J.

1987-01-01

An explosive-actuated, fast-acting arcless switch contains a highly conductive foil to carry high currents positioned adjacent a dielectric surface within a casing. At one side of the foil opposite the dielectric surface is an explosive which, when detonated, drives the conductive foil against the dielectric surface. A pattern of grooves in the dielectric surface ruptures the foil to establish a rupture path having a pattern corresponding to the pattern of the grooves. The impedance of the ruptured foil is greater than that of the original foil to divert high current to a load. Planar and cylindrical embodiments of the switch are disclosed.

Postural loading assessment in assembly workers of an Iranian telecommunication manufacturing company.

PubMed

Kamalinia, Mojtaba; Nasl Saraji, Gebreal; Kee, Dohyung; Hosseini, Mostafa; Choobineh, Alireza

2013-01-01

Changes in industries and work practices have coincided with work-related musculoskeletal disorders (MSDs). This study was conducted to determine the prevalence of MSDs and to assess postural loading in assembly workers of an Iranian telecommunication manufacturing company. Data were collected from 193 randomly selected workers in 4 units of the company. The Nordic musculoskeletal disorders questionnaire and the UBC ergonomic checklist were used as data collection tools. Loading on the upper body assessment (LUBA) was used to assess postural loading. Lower back symptoms were the most prevalent problems among the workers (67.9%). LUBA showed that most assembly workers (94.3%) had experienced considerable and high postural loading (postural load index, PLI > 5). Regression analyses revealed that lighting, rotation, contact stress, repetition, gender and age were factors associated with symptoms. Work-related MSDs occurred at a high rate among workers. Postural loading requires consideration. Any ergonomic intervention should focus on eliminating ergonomic factors associated with symptoms.

Synthesis, Chemical and Physical Characterization of TKX-50

NASA Astrophysics Data System (ADS)

Klapoetke, Thomas

2015-06-01

TKX-50 (bis(hydroxylammonium) 5,5'-bis(tetrazolate-1 N-oxide)) is one of the most promising ionic salts as a possible replacement for RDX. The thermal behavior of TKX-50 (bis(hydroxylammonium) 5,5'-(tetrazolate-1 N-oxide)) and the kinetics of its thermal decomposition were studied using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The calculated results of the detonation parameters and equations of state for the detonation products (EOS DP) of explosive materials TKX-50 and MAD-X1 and several of their derivatives were obtained using the computer program EXPLO5 V.6.01. These values were also calculated for standard explosive materials which are commonly used such as TNT, PETN, RDX, HMX as well as for the more powerful explosive material CL-20 to allow comparisons to be made. The determination of the detonation parameters and EOS DP was conducted both for explosive materials having the maximum crystalline density and for porous right up to 50% in volume materials. The influence of the content of plastic binder polyisobutylene used (up to 20% in volume) on all of the investigated properties was also examined. Calculated results on shock wave loading of different inert barriers in a wide range of their dynamic properties under explosion on their surfaces of concrete size charges of different explosive materials in various initial states were obtained with the use of the one-dimensional computer hydrocode EP. Barriers due to materials such as polystyrene, textolite, magnesium, aluminum, zinc, copper, tantalum or tungsten were examined (Fig. 1). Initial values of pressure and other parameters of loading on the interface explosive-barrier were determined in the process of conducted calculations. Phenomena of propagation and attenuation of shock waves in barrier materials were considered too for all possible situations. From these calculations, an essentially complete overview of the explosion properties and characteristics of shock wave action onto barriers was obtained for several new and also for several standard explosive materials as a comparison. Work done in collaboration with Golubev/Fischer/Stierstorfer/Bohanek/Dobrilovic.

Explosion containment device

DOEpatents

Benedick, William B.; Daniel, Charles J.

1977-01-01

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

Shock Initiated Reactions of Reactive Multiphase Blast Explosives

NASA Astrophysics Data System (ADS)

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

2015-06-01

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

A Combustion Model for the TWA 800 Center-Wing Fuel Tank Explosion

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

Baer, M.R.; Gross, R.J.

1998-10-02

In support of the National Transportation Safety Board investigation of the TWA Flight 800 accident, a combined experimental/computational effort was conducted that focused on quarter-scale testing and simulation of the fuel-air explosion in the Boeing 747 center wing fuel tank. This report summarizes the modeling approach used at Sandia National Laboratories. In this approach approximations are introduced that capture the essential physics associated with turbulent flame propagation in multiple compartment fuel tanks. This model efficiently defines the pressure loading conditions during a jet-fuel air explosion in a fuel tank confinement. Modeling calculations compare favorably with a variety of experimental quarter-scalemore » tests conducted in rigid confinement. The modeling describes well the overpressure history in several geometry configurations. Upon demonstrating a reasonable comparison to experimental observations, a parametric study of eight possible ignition sources is then discussed. Model calculations demonstrate that different loading conditions arise as the location of the ignition event is varied. By comparing the inferred damage and calculated impulses to that seen in the recovered tank, it maybe possible to reduce the number of likely sources. A possible extension of this work to better define tank damage includes coupling the combustion model as a pressure loading routine for structural failure analysis.« less

Solid explosive plane-wave lenses pressed-to-shape with dies

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

Olinger, B.

2007-11-01

Solid-explosive plane-wave lenses 1", 2" and 4¼" in diameter have been mass-produced from components pressed-to-shape with aluminum dies. The method used to calculate the contour between the solid plane-wave lens components pressed-to-shape with the dies is explained. The steps taken to press, machine, and assemble the lenses are described. The method of testing the lenses, the results of those tests, and the corrections to the dies are reviewed. The work on the ½", 8", and 12" diameter lenses is also discussed.

EDS V25 containment vessel explosive qualification test report.

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

Rudolphi, John Joseph

2012-04-01

The V25 containment vessel was procured by the Project Manager, Non-Stockpile Chemical Materiel (PMNSCM) as a replacement vessel for use on the P2 Explosive Destruction Systems. It is the first EDS vessel to be fabricated under Code Case 2564 of the ASME Boiler and Pressure Vessel Code, which provides rules for the design of impulsively loaded vessels. The explosive rating for the vessel based on the Code Case is nine (9) pounds TNT-equivalent for up to 637 detonations. This limit is an increase from the 4.8 pounds TNT-equivalency rating for previous vessels. This report describes the explosive qualification tests thatmore » were performed in the vessel as part of the process for qualifying the vessel for explosive use. The tests consisted of a 11.25 pound TNT equivalent bare charge detonation followed by a 9 pound TNT equivalent detonation.« less

Explosive vessel for coupling dynamic experiments to the X-ray beam at the Advanced Photon Source

NASA Astrophysics Data System (ADS)

Owens, Charles; Sanchez, Nathaniel; Sorensen, Christian; Jensen, Brian

2017-06-01

Recent experiments at the Advanced Photon Source have been successful in coupling gun systems to the synchrotron to take advantage of the advanced X-ray diagnostics available including X-ray diffraction and X-ray phase contrast imaging (PCI) to examine matter at extreme conditions. There are many experiments that require explosive loading capabilities, e.g. detonator and initiator dynamics, small angle X-ray scattering (SAXS), ejecta formation, and explosively driven flyer experiments. The current work highlights a new explosive vessel that was designed specifically for use at a synchrotron facility with requirements to confine up to 15 grams of explosives (TNT equivalent), couple the vessel to the X-ray beam line, and reliably position samples remotely. A description of the system and capability will be provided along with the results from qualification testing to bring the system into service (LA-UR-17-21381).

Computer simulation of metal wire explosion under high rate heating

NASA Astrophysics Data System (ADS)

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

2017-05-01

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

Strength of the phase change materials on loading with the products of electric explosion of conductors

NASA Astrophysics Data System (ADS)

Savenkov, Georgiy; Morozov, Viktor; Kats, Victor

2018-05-01

Results of the experimentation on the destruction of the phase change materials (beeswax and paraffin) by the electric explosion of conductors are presented. The process of the explosion of copper and nickel titanium wires in both pure PCM and its mixture with nonosized additives of cuprous oxide is analyzed. The effect of this additive on the process of the expansion of the electric-discharge plasma during the electric explosion of conductors and on the strength of composite materials is demonstrated. The piezoprobe-based method of measurement of the radial pressure during samples destruction is developed. The experiments made it possible to determine the dimensions of the melting channel formed inside the samples during the explosion and the subsequent expansion of the electric-discharge plasma. The experiments are performed on the generator of short-term high-voltage pulses capable to shape the voltage of (10-24) kV.

Numerical simulation of the fluid-structure interaction between air blast waves and soil structure

NASA Astrophysics Data System (ADS)

Umar, S.; Risby, M. S.; Albert, A. Luthfi; Norazman, M.; Ariffin, I.; Alias, Y. Muhamad

2014-03-01

Normally, an explosion threat on free field especially from high explosives is very dangerous due to the ground shocks generated that have high impulsive load. Nowadays, explosion threats do not only occur in the battlefield, but also in industries and urban areas. In industries such as oil and gas, explosion threats may occur on logistic transportation, maintenance, production, and distribution pipeline that are located underground to supply crude oil. Therefore, the appropriate blast resistances are a priority requirement that can be obtained through an assessment on the structural response, material strength and impact pattern of material due to ground shock. A highly impulsive load from ground shocks is a dynamic load due to its loading time which is faster than ground response time. Of late, almost all blast studies consider and analyze the ground shock in the fluid-structure interaction (FSI) because of its influence on the propagation and interaction of ground shock. Furthermore, analysis in the FSI integrates action of ground shock and reaction of ground on calculations of velocity, pressure and force. Therefore, this integration of the FSI has the capability to deliver the ground shock analysis on simulation to be closer to experimental investigation results. In this study, the FSI was implemented on AUTODYN computer code by using Euler-Godunov and the arbitrary Lagrangian-Eulerian (ALE). Euler-Godunov has the capability to deliver a structural computation on a 3D analysis, while ALE delivers an arbitrary calculation that is appropriate for a FSI analysis. In addition, ALE scheme delivers fine approach on little deformation analysis with an arbitrary motion, while the Euler-Godunov scheme delivers fine approach on a large deformation analysis. An integrated scheme based on Euler-Godunov and the arbitrary Lagrangian-Eulerian allows us to analyze the blast propagation waves and structural interaction simultaneously.

Nitrogen enrichment suppresses other environmental drivers and homogenizes salt marsh leaf microbiome

DOE PAGES

Daleo, Pedro; Alberti, Juan; Jumpponen, Ari; ...

2018-04-12

Microbial community assembly is affected by a combination of forces that act simultaneously, but the mechanisms underpinning their relative influences remain elusive. This gap strongly limits our ability to predict human impacts on microbial communities and the processes they regulate. Here, we experimentally demonstrate that increased salinity stress, food web alteration and nutrient loading interact to drive outcomes in salt marsh fungal leaf communities. Both salinity stress and food web alterations drove communities to deterministically diverge, resulting in distinct fungal communities. Increased nutrient loads, nevertheless, partially suppressed the influence of other factors as determinants of fungal assembly. Using a nullmore » model approach, we found that increased nutrient loads enhanced the relative importance of stochastic over deterministic divergent processes; without increased nutrient loads, samples from different treatments showed a relatively (deterministic) divergent community assembly whereas increased nutrient loads drove the system to more stochastic assemblies, suppressing the effect of other treatments. These results demonstrate that common anthropogenic modifications can interact to control fungal community assembly. As a result, our results suggest that when the environmental conditions are spatially heterogeneous (as in our case, caused by specific combinations of experimental treatments), increased stochasticity caused by greater nutrient inputs can reduce the importance of deterministic filters that otherwise caused divergence, thus driving to microbial community homogenization.« less

Nitrogen enrichment suppresses other environmental drivers and homogenizes salt marsh leaf microbiome.

PubMed

Daleo, Pedro; Alberti, Juan; Jumpponen, Ari; Veach, Allison; Ialonardi, Florencia; Iribarne, Oscar; Silliman, Brian

2018-06-01

Microbial community assembly is affected by a combination of forces that act simultaneously, but the mechanisms underpinning their relative influences remain elusive. This gap strongly limits our ability to predict human impacts on microbial communities and the processes they regulate. Here, we experimentally demonstrate that increased salinity stress, food web alteration and nutrient loading interact to drive outcomes in salt marsh fungal leaf communities. Both salinity stress and food web alterations drove communities to deterministically diverge, resulting in distinct fungal communities. Increased nutrient loads, nevertheless, partially suppressed the influence of other factors as determinants of fungal assembly. Using a null model approach, we found that increased nutrient loads enhanced the relative importance of stochastic over deterministic divergent processes; without increased nutrient loads, samples from different treatments showed a relatively (deterministic) divergent community assembly whereas increased nutrient loads drove the system to more stochastic assemblies, suppressing the effect of other treatments. These results demonstrate that common anthropogenic modifications can interact to control fungal community assembly. Furthermore, our results suggest that when the environmental conditions are spatially heterogeneous (as in our case, caused by specific combinations of experimental treatments), increased stochasticity caused by greater nutrient inputs can reduce the importance of deterministic filters that otherwise caused divergence, thus driving to microbial community homogenization. © 2018 by the Ecological Society of America.

Nitrogen enrichment suppresses other environmental drivers and homogenizes salt marsh leaf microbiome

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

Daleo, Pedro; Alberti, Juan; Jumpponen, Ari

Microbial community assembly is affected by a combination of forces that act simultaneously, but the mechanisms underpinning their relative influences remain elusive. This gap strongly limits our ability to predict human impacts on microbial communities and the processes they regulate. Here, we experimentally demonstrate that increased salinity stress, food web alteration and nutrient loading interact to drive outcomes in salt marsh fungal leaf communities. Both salinity stress and food web alterations drove communities to deterministically diverge, resulting in distinct fungal communities. Increased nutrient loads, nevertheless, partially suppressed the influence of other factors as determinants of fungal assembly. Using a nullmore » model approach, we found that increased nutrient loads enhanced the relative importance of stochastic over deterministic divergent processes; without increased nutrient loads, samples from different treatments showed a relatively (deterministic) divergent community assembly whereas increased nutrient loads drove the system to more stochastic assemblies, suppressing the effect of other treatments. These results demonstrate that common anthropogenic modifications can interact to control fungal community assembly. As a result, our results suggest that when the environmental conditions are spatially heterogeneous (as in our case, caused by specific combinations of experimental treatments), increased stochasticity caused by greater nutrient inputs can reduce the importance of deterministic filters that otherwise caused divergence, thus driving to microbial community homogenization.« less

30 CFR 18.80 - Approval of machines assembled with certified or explosion-proof components.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Modifications of Approved Machines, and Permits To Use Experimental Equipment § 18.80 Approval of machines... approval. A design of the approval plate will accompany the notification of approval. (Refer to §§ 18.10...

30 CFR 18.80 - Approval of machines assembled with certified or explosion-proof components.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Modifications of Approved Machines, and Permits To Use Experimental Equipment § 18.80 Approval of machines... approval. A design of the approval plate will accompany the notification of approval. (Refer to §§ 18.10...

30 CFR 18.80 - Approval of machines assembled with certified or explosion-proof components.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Modifications of Approved Machines, and Permits To Use Experimental Equipment § 18.80 Approval of machines... approval. A design of the approval plate will accompany the notification of approval. (Refer to §§ 18.10...

30 CFR 18.80 - Approval of machines assembled with certified or explosion-proof components.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Modifications of Approved Machines, and Permits To Use Experimental Equipment § 18.80 Approval of machines... approval. A design of the approval plate will accompany the notification of approval. (Refer to §§ 18.10...

Courtland Target Assembly Facility Environmental Assessment

DTIC Science & Technology

2006-10-01

Draft Environmental Assessment 2-17 tributyl phosphate (TBP)6, diatomaceous earth, talcum powder, cornmeal , water, steel, and plastic. 2.2.2... cornmeal , water, steel, and plastic that would not qualify as hazardous materials. TBP is non-explosive, non-flammable, and stable under normal

Explosives Removal from Munitions Wastewaters

DTIC Science & Technology

1975-01-01

activated carbon columns. Waste water, for the study was drawn as needed from the effluent of the i diatomaceous earth filters and stored in an 800-gallon...explosive Laterials, such as DNT and nitrocresols, from waste streams. The loaded adsorbent can be regenerated with solvent. To minimize operating costs...most effective is fixed-bed adsorption followir.nI clarification and filtration to remove suspended j solids. Activated carbon adsorbent is used at a

Dynamic loading and release in Johnson Space Center Lunar regolith simulant

NASA Astrophysics Data System (ADS)

Plesko, C. S.; Jensen, B. J.; Wescott, B. L.; Skinner McKee, T. E.

2011-10-01

The behavior of regolith under dynamic loading is important for the study of planetary evolution, impact cratering, and other topics. Here we present the initial results of explosively driven flier plate experiments and numerical models of compaction and release in samples of the JSC-1A Lunar regolith simulant.

Hot spot initiation and chemical reaction in shocked polymeric bonded explosives

NASA Astrophysics Data System (ADS)

An, Qi; Zybin, Sergey; Jaramillo-Botero, Andres; Goddard, William; Materials; Process Simulation Center, Caltech Team

2011-06-01

A polymer bonded explosive (PBX) model based on PBXN-106 is studied via molecular dynamics (MD) simulations using reactive force field (ReaxFF) under shock loading conditions. Hotspot is observed when shock waves pass through the non-planar interface of explosives and elastomers. Adiabatic shear localization is proposed as the main mechanism of hotspot ignition in PBX for high velocity impact. Our simulation also shows that the coupling of shear localization and chemical reactions at hotspot region play important rules at stress relaxtion for explosives. The phenomenon that shock waves are obsorbed by elastomers is also observed in the MD simulations. This research received supports from ARO (W911NF-05-1-0345; W911NF-08-1-0124), ONR (N00014-05-1-0778), and Los Alamos National Laboratory (LANL).

Initiation disruptor systems and methods of initiation disruption

DOEpatents

Baum, Dennis W

2014-09-23

A system that may be used as an initiation disruption system (IDS) according to one embodiment includes an explosive charge; a plurality of particles in a layer at least partially surrounding the explosive charge; and a fire suppressant adjacent the plurality of particles. A method for disabling an object according to one embodiment includes placing the system as recited above near an object; and causing the explosive charge to initiate, thereby applying mechanical loading to the object such that the object becomes disabled. Additional systems and methods are also presented. A device according to another embodiment includes a plurality of particles bound by a binder thereby defining a sidewall having an interior for receiving an explosive; and a fire suppressant adjacent the plurality of particles and binder. Additional systems and methods are also presented.

Solid phase microextraction field kit

DOEpatents

Nunes, Peter J.; Andresen, Brian D.

2005-08-16

A field kit for the collection, isolation and concentration of trace amounts of high explosives (HE), biological weapons (BW) and chemical weapons (CW) residues in air, soil, vegetation, swipe, and liquid samples. The field kit includes a number of Solid Phase Microextraction (SPME) fiber and syringe assemblies in a hermetically sealed transportation container or tubes which includes a sampling port, a number of extra SPME fiber and syringe assemblies, the fiber and syringe assemblies including a protective cap for the fiber, and an extractor for the protective cap, along with other items including spare parts, protective glove, and an instruction manual, all located in an airtight container.

Load beam unit replaceable inserts for dry coal extrusion pumps

DOEpatents

Saunders, Timothy; Brady, John D.

2012-11-13

A track assembly for a particulate material extrusion pump according to an exemplary aspect of the present disclosure includes a link assembly with a roller bearing. An insert mounted to a load beam located such that the roller bearing contacts the insert.

Resurgent Russia in 2030. Challenge for the USAF

DTIC Science & Technology

2009-09-01

real-time unfiltered news and information from the Internet.33 For example, Chechen sup- porters posted videos on YouTube showing improvised explosive...Future Shane P. Courville, December 2007 64 Next Generation Nanotechnology Assembly Fabrication Methods: A Trend Forecast Vincent T. Jovene , Jr

30 CFR 18.80 - Approval of machines assembled with certified or explosion-proof components.

Code of Federal Regulations, 2014 CFR

2014-07-01

... approved machines will be accepted in lieu of certified components. (b) A single layout drawing (see Figure... approval. A design of the approval plate will accompany the notification of approval. (Refer to §§ 18.10...

A fluorescent organic cage for picric acid detection.

PubMed

Acharyya, Koushik; Mukherjee, Partha Sarathi

2014-12-25

Dynamic covalent imine chemistry has been utilized to synthesize a fluorescent [3+2] self-assembled nanoscopic organic cage. The fluorescent nature of the reduced analogue of the cage was further exploited for the highly selective detection of the explosive picric acid (PA).

Musculoskeletal disorder risk during automotive assembly: current vs. seated

PubMed Central

Ferguson, Sue A.; Marras, William S.; Allread, W. Gary; Knapik, Gregory G.; Splittstoesser, Riley E.

2013-01-01

Musculoskeletal disorder risk was assessed during automotive assembly processes. The risk associated with current assembly processes was compared to using a cantilever chair intervention. Spine loads and normalized shoulder muscle activity were evaluated during assembly in eight regions of the vehicle. Eight interior cabin regions of the vehicle were classified by reach distance, height from vehicle floor and front to back. The cantilever chair intervention tool was most effective in the far reach regions regardless of the height. In the front far reach regions both spine loads and normalized shoulder muscle activity levels were reduced. In the middle and close reach regions spine loads were reduced, however, shoulder muscle activity was not, thus an additional intervention would be necessary to reduce shoulder risk. In the back far reach region, spine loads were not significantly different between the current and cantilever chair conditions. Thus, the effectiveness of the cantilever chair was dependent on the region of the vehicle. PMID:22036450

Credit BG. The north and west sides of this structure ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Credit BG. The north and west sides of this structure appear as seen when looking east (88°). Building E-67, the tunnel entrance, gives personnel access to the tunnel system. The Assembly Building served as a shop for test crews; it contained a small lathe and other tools for making specialized parts. No explosives were allowed in this structure. Air conditioning ducts are on the roof - Jet Propulsion Laboratory Edwards Facility, Assembly Building, Edwards Air Force Base, Boron, Kern County, CA

Enzyme-free Detection of Hydrogen Peroxide from Cerium Oxide Nanoparticles Immobilized on Poly(4-vinylpyridine) Self-Assembled Monolayers

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

Gaynor, James D.; Karakoti, Ajay S.; Inerbaev, Talgat

2013-05-02

A single layer of oxygen-deficient cerium oxide nanoparticles (CNPs) are immobilized on microscopic glass slide using poly(4-vinylpyridine) (PVP) self-assembled monolayers (SAMs). A specific colorimetric property of CNPs when reacted with hydrogen peroxide allows for the direct, single-step peroxide detection which can be used in medical diagnosis and explosives detection. Multiple PVP-CNP immobilized layers improve sensitivity of detection and the sensor can be regenerated for reuse.

Explosive-driven, high speed, arcless switch

DOEpatents

Skogmo, P.J.; Tucker, T.J.

1987-07-14

An explosive-actuated, fast-acting arcless switch contains a highly conductive foil to carry high currents positioned adjacent a dielectric surface within a casing. At one side of the foil opposite the dielectric surface is an explosive which, when detonated, drives the conductive foil against the dielectric surface. A pattern of grooves in the dielectric surface ruptures the foil to establish a rupture path having a pattern corresponding to the pattern of the grooves. The impedance of the ruptured foil is greater than that of the original foil to divert high current to a load. Planar and cylindrical embodiments of the switch are disclosed. 7 figs.

Improved explosive collection and detection with rationally assembled surface sampling materials

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

Chouyyok, Wilaiwan; Bays, J. Timothy; Gerasimenko, Aleksandr A.

Sampling and detection of trace explosives is a key analytical process in modern transportation safety. In this work we have explored some of the fundamental analytical processes for collection and detection of trace level explosive on surfaces with the most widely utilized system, thermal desorption IMS. The performance of the standard muslin swipe material was compared with chemically modified fiberglass cloth. The fiberglass surface was modified to include phenyl functional groups. When compared to standard muslin, the phenyl functionalized fiberglass sampling material showed better analyte release from the sampling material as well as improved response and repeatability from multiple usesmore » of the same swipe. The improved sample release of the functionalized fiberglass swipes resulted in a significant increase in sensitivity. Various physical and chemical properties were systematically explored to determine optimal performance. The results herein have relevance to improving the detection of other explosive compounds and potentially to a wide range of other chemical sampling and field detection challenges.« less

75 FR 69612 - Airworthiness Directives; The Boeing Company Model 747-200B, -300, -400, -400D, and -400F Series...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-15

... loss of the spring beam load path and the possible separation of a strut and engine from the airplane... mid-pivot bolt assembly could result in the loss of the spring beam load path. Loss of the spring beam...-pivot bolt assembly, which could lead to loss of the spring beam load path and the possible separation...

Ceramic Life Prediction Parameters

DTIC Science & Technology

1980-05-01

preferential. A standard creep testing Satec machine with a modified load train assembly was used for tensile stress-rupture testing. The specimen is...to the standard Satec machine head which includes crossed (90°) knife edges. The assembly procedure includes hanging the load train parts from...the Satec head as influenced by gravity. At this point the lower Satec crossarm is lowered to snub the train in this position. The load train

Dicer is dispensable for asymmetric RISC loading in mammals

PubMed Central

Betancur, Juan G.; Tomari, Yukihide

2012-01-01

In flies, asymmetric loading of small RNA duplexes into Argonaute2-containing RNA-induced silencing complex (Ago2-RISC) requires Dicer-2/R2D2 heterodimer, which acts as a protein sensor for the thermodynamic stabilities of the ends of small RNA duplexes. However, the mechanism of small RNA asymmetry sensing in mammalian RISC assembly remains obscure. Here, we quantitatively examined RISC assembly and target silencing activity in the presence or absence of Dicer in mammals. Our data show that, unlike the well-characterized fly Ago2-RISC assembly pathway, mammalian Dicer is dispensable for asymmetric RISC loading in vivo and in vitro. PMID:22106413

Dicer is dispensable for asymmetric RISC loading in mammals.

PubMed

Betancur, Juan G; Tomari, Yukihide

2012-01-01

In flies, asymmetric loading of small RNA duplexes into Argonaute2-containing RNA-induced silencing complex (Ago2-RISC) requires Dicer-2/R2D2 heterodimer, which acts as a protein sensor for the thermodynamic stabilities of the ends of small RNA duplexes. However, the mechanism of small RNA asymmetry sensing in mammalian RISC assembly remains obscure. Here, we quantitatively examined RISC assembly and target silencing activity in the presence or absence of Dicer in mammals. Our data show that, unlike the well-characterized fly Ago2-RISC assembly pathway, mammalian Dicer is dispensable for asymmetric RISC loading in vivo and in vitro.

Optimization of reinforced concrete slabs

NASA Technical Reports Server (NTRS)

Ferritto, J. M.

1979-01-01

Reinforced concrete cells composed of concrete slabs and used to limit the effects of accidental explosions during hazardous explosives operations are analyzed. An automated design procedure which considers the dynamic nonlinear behavior of the reinforced concrete of arbitrary geometrical and structural configuration subjected to dynamic pressure loading is discussed. The optimum design of the slab is examined using an interior penalty function. The optimization procedure is presented and the results are discussed and compared with finite element analysis.

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

NASA Astrophysics Data System (ADS)

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

2013-06-01

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

Low-impact mating system

NASA Technical Reports Server (NTRS)

Lewis, James L. (Inventor); Carroll, Monty B. (Inventor); Le, Thang D. (Inventor); Morales, Ray H. (Inventor); Robertson, Brandan R. (Inventor)

2009-01-01

An androgynous mating system for mating two exoatmospheric space modules comprising a first mating assembly capable of mating with a second mating assembly; a second mating assembly structurally identical to said first mating assembly, said first mating assembly comprising; a load ring; a plurality of load cell subassemblies; a plurality of actuators; a base ring; a tunnel; a closed loop control system; one or more electromagnets; and one or more striker plates, wherein said one or more electomagnets on said second mating assembly are capable of mating with said one or more striker plates on said first mating assembly, and wherein said one or more striker plates is comprised of a plate of predetermined shape and a 5-DOF mechanism capable of maintaining predetermined contact requirements during said mating of said one or more electromagnets and said one or more striker plates.

Dynamic Fracture Behavior of Plastic-Bonded Explosives

NASA Astrophysics Data System (ADS)

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

2011-06-01

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

10 CFR 810.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... of neutrons used to effect SNM production in the “subcritical assembly.” Agreement for cooperation... International Atomic Energy Agency. Non-nuclear-weapon state is a country not recognized as a nuclear-weapon...-Proliferation of Nuclear Weapons. Nuclear reactor means an apparatus, other than a nuclear explosive device...

10 CFR 810.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... of neutrons used to effect SNM production in the “subcritical assembly.” Agreement for cooperation... International Atomic Energy Agency. Non-nuclear-weapon state is a country not recognized as a nuclear-weapon...-Proliferation of Nuclear Weapons. Nuclear reactor means an apparatus, other than a nuclear explosive device...

30 CFR 18.34 - Motors.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.34 Motors. Explosion-proof electric motor assemblies intended for use in approved equipment in underground... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Motors. 18.34 Section 18.34 Mineral Resources...

49 CFR 173.62 - Specific packaging requirements for explosives.

Code of Federal Regulations, 2011 CFR

2011-10-01

... article or material carried in the vehicle; and (ii) The assembled gun packed on the vehicle may not... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS... kg in small packages as specified by the Associate Administrator for Hazardous Materials Safety 110(a...

49 CFR 173.62 - Specific packaging requirements for explosives.

Code of Federal Regulations, 2012 CFR

2012-10-01

... article or material carried in the vehicle; and (ii) The assembled gun packed on the vehicle may not... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS... packages as specified by the Associate Administrator for Hazardous Materials Safety 110(a) Bags Bags Drums...

Shock Equation of State of Multi-Phase Epoxy-Based Composite (Al-MnO2-Epoxy)

DTIC Science & Technology

2010-10-01

single stage light gas gun , two...using three different loading techniques— single stage light gas gun , two stage light gas gun , and explosive loading—with multiple diagnostic...wave speed. B. Single stage gas gun loading experiments Four gas gun -driven equation of state experiments were conducted at NSWC-Indian Head using

23. BUILDING NO. 452, ORDNANCE FACILITY (BAG CHARGE FILLING PLANT), ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. BUILDING NO. 452, ORDNANCE FACILITY (BAG CHARGE FILLING PLANT), INTERIOR, LOOKING SOUTH DOWN CENTRAL CORRIDOR. NOTE BINS IN WALLS ON EITHER SIDE OF CORRIDOR, USED FOR PASSING EXPLOSIVES AND LOADED ITEMS TO SIEVING ROOMS BEYOND WALLS. - Picatinny Arsenal, 400 Area, Gun Bag Loading District, State Route 15 near I-80, Dover, Morris County, NJ

Acceleration of plates using non-conventional explosives heavily-loaded with inert materials

NASA Astrophysics Data System (ADS)

Loiseau, J.; Petel, O. E.; Huneault, J.; Serge, M.; Frost, D. L.; Higgins, A. J.

2014-05-01

The detonation behavior of high explosives containing quantities of dense additives has been previously investigated with the observation that such systems depart dramatically from the approximately "gamma law" behavior typical of conventional explosives due to momentum transfer and thermalization between particles and detonation products. However, the influence of this non-ideal detonation behavior on the divergence speed of plates has been less thoroughly studied and existing literature suggests that the effect of dense additives cannot be explained solely through the straightforward application of the Gurney method with energy and density averaging of the explosive. In the current study, the acceleration history and terminal velocity of aluminum flyers launched by packed beds of granular material saturated by amine-sensitized nitromethane is reported. It was observed that terminal flyer velocity scales primarily with the ratio of flyer mass to mass of the explosive component; a fundamental feature of the Gurney method. Velocity decrement from the addition of particles was only 20%-30% compared to the resulting velocity if propelled by an equivalent quantity of neat explosive.

In-Situ X-ray Tomography Observation of Structure Evolution in 1,3,5-Triamino-2,4,6-Trinitrobenzene Based Polymer Bonded Explosive (TATB-PBX) under Thermo-Mechanical Loading.

PubMed

Yuan, Zeng-Nian; Chen, Hua; Li, Jing-Ming; Dai, Bin; Zhang, Wei-Bin

2018-05-04

In order to study the fracture behavior and structure evolution of 1,3,5-Triamino-2,4,6-Trinitrobenzene (TATB)-based polymer bonded explosive in thermal-mechanical loading, in-situ studies were performed on X-ray computed tomography system using quasi-static Brazilian test. The experiment temperature was set from −20 °C to 70 °C. Three-dimensional morphology of cracks at different temperatures was obtained through digital image process. The various fracture modes were compared by scanning electron microscopy. Fracture degree and complexity were defined to quantitatively characterize the different types of fractures. Fractal dimension was used to characterize the roughness of the crack surface. The displacement field of particles in polymer bonded explosive (PBX) was used to analyze the interior structure evolution during the process of thermal-mechanical loading. It was found that the brittleness of PBX reduced, the fracture got more tortuous, and the crack surface got smoother as the temperature rose. At lower temperatures, especially lower than glass transition temperature of binders, there were slipping and shear among particles, and particles tended to displace and disperse; while at higher temperatures, especially above the glass transition temperature of binders, there was reorganization of particles and particles tended to merge, disperse, and reduce sizes, rather than displacing.

Consistent criticality and radiation studies of Swiss spent nuclear fuel: The CS2M approach.

PubMed

Rochman, D; Vasiliev, A; Ferroukhi, H; Pecchia, M

2018-06-15

In this paper, a new method is proposed to systematically calculate at the same time canister loading curves and radiation sources, based on the inventory information from an in-core fuel management system. As a demonstration, the isotopic contents of the assemblies come from a Swiss PWR, considering more than 6000 cases from 34 reactor cycles. The CS 2 M approach consists in combining four codes: CASMO and SIMULATE to extract the assembly characteristics (based on validated models), the SNF code for source emission and MCNP for criticality calculations for specific canister loadings. The considered cases cover enrichments from 1.9 to 5.0% for the UO 2 assemblies and 4.8% for the MOX, with assembly burnup values from 7 to 74 MWd/kgU. Because such a study is based on the individual fuel assembly history, it opens the possibility to optimize canister loadings from the point-of-view of criticality, decay heat and emission sources. Copyright © 2018 Elsevier B.V. All rights reserved.

The High-Strain Rate Loading of Structural Biological Materials

NASA Astrophysics Data System (ADS)

Proud, W. G.; Nguyen, T.-T. N.; Bo, C.; Butler, B. J.; Boddy, R. L.; Williams, A.; Masouros, S.; Brown, K. A.

2015-10-01

The human body can be subjected to violent acceleration as a result of explosion caused by military ordinance or accident. Blast waves cause injury and blunt trauma can be produced by violent impact of objects against the human body. The long-term clinical manifestations of blast injury can be significantly different in nature and extent to those suffering less aggressive insult. Similarly, the damage seen in lower limbs from those injured in explosion incidents is in general more severe than those falling from height. These phenomena increase the need for knowledge of the short- and long-term effect of transient mechanical loading to the biological structures of the human body. This paper gives an overview of some of the results of collaborative investigation into blast injury. The requirement for time-resolved data, appropriate mechanical modeling, materials characterization and biological effects is presented. The use of a range of loading platforms, universal testing machines, drop weights, Hopkinson bars, and bespoke traumatic injury simulators are given.

Apollo Spacecraft and Saturn V Launch Vehicle Pyrotechnics/Explosive Devices

NASA Technical Reports Server (NTRS)

Interbartolo, Michael

2009-01-01

The Apollo Mission employs more than 210 pyrotechnic devices per mission.These devices are either automatic of commanded from the Apollo spacecraft systems. All devices require high reliability and safety and most are classified as either crew safety critical or mission critical. Pyrotechnic devices have a wide variety of applications including: launch escape tower separation, separation rocket ignition, parachute deployment and release and electrical circuit opening and closing. This viewgraph presentation identifies critical performance, design requirements and safety measures used to ensure quality, reliability and performance of Apollo pyrotechnic/explosive devices. The major components and functions of a typical Apollo pyrotechnic/explosive device are listed and described (initiators, cartridge assemblies, detonators, core charges). The presentation also identifies the major locations and uses for the devices on: the Command and Service Module, Lunar Module and all stages of the launch vehicle.

V27 Test Report.

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

Stofleth, Jerome H.; Tribble, Megan Kimberly; Crocker, Robert W.

2017-05-01

The V27 containment vessel was procured by the US Army Recovered Chemical Material Directorate ( RCMD ) as a replacement vessel for use on the P2 Explosive Destruction Systems. It is the third EDS vessel to be fabricated under Code Case 2564 of the ASME Boiler and Pressure Vessel Code, which provides rules for the design of impulsively loaded vessels. The explosive rating for the vessel, based on the Code Case, is nine (9) pounds TNT - equivalent for up to 637 detonations . This report documents the results of explosive tests that were done on the vessel at Sandiamore » National Laboratories in Albuquerque New Mexico to qualify the vessel for explosive use . The primary qualification test consisted of si x 1.5 pound charges of Composition C - 4 (equivalent to 11.25 pounds TNT) distributed around the vessel in accordance with the User Design Specification. Four subsequent tests using less explosive evaluated the effects of slight variations in orientation of the charges . All vessel acceptance criteria were met.« less

The recovery and analysis of mitochondrial DNA from exploded pipe bombs.

PubMed

Foran, David R; Gehring, Michael E; Stallworth, Shawn E

2009-01-01

Improvised explosive devices (IEDs) represent one of the most common modes of arbitrarily injuring or killing human beings. Because of the heat generated by, and destruction to, an IED postconflagration, most methods for identifying who assembled the device are ineffective. In the research presented, steel pipe bombs were mock-assembled by volunteers, and the bombs detonated under controlled conditions. The resultant shrapnel was collected and swabbed for residual cellular material. Mitochondrial DNA profiles were generated and compared blind to the pool of individuals who assembled the bombs. Assemblers were correctly identified 50% of the time, while another 19% could be placed into a group of three individuals with shared haplotypes. Only one bomb was assigned incorrectly. In some instances a contaminating profile (mixture) was also observed. Taken together, the results speak to the extreme sensitivity the methods have for identifying those who assemble IEDs, along with precautions needed when collecting and processing such evidence.

Size effect and cylinder test on several commercial explosives

NASA Astrophysics Data System (ADS)

Souers, P. Clark; Lauderbach, Lisa; Moua, Kou; Garza, Raul

2012-03-01

Some size (diameter) effect and the Cylinder test results for Kinepak (ammonium nitrate/nitromethane), Semtex 1, Semtex H and urea nitrate are presented. Cylinder test data appears normal despite faster sound speeds in the copper wall. Most explosives come to steady state in the Cylinder test as expected, but Kinepak shows a steadily increasing wall velocity with distance down the cylinder. Some data on powder densities as a function of loading procedure are also given.

Method of rubblization for in-situ oil shale processing

NASA Technical Reports Server (NTRS)

Yang, Lien C. (Inventor)

1985-01-01

A method that produces a uniformly rubblized oil shale bed of desirable porosity for underground, in-situ heat extraction of oil. Rubblization is the generation of rubble of various sized fragments. The method uses explosive loadings lying at different levels in adjacent holes and detonation of the explosives at different levels in sequence to achieve the fracturing and the subsequent expansion of the fractured oil shale into excavated rooms both above and below the hole pattern.

Dynamic Fracture Simulations of Explosively Loaded Cylinders

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

Arthur, Carly W.; Goto, D. M.

2015-11-30

This report documents the modeling results of high explosive experiments investigating dynamic fracture of steel (AerMet® 100 alloy) cylinders. The experiments were conducted at Lawrence Livermore National Laboratory (LLNL) during 2007 to 2008 [10]. A principal objective of this study was to gain an understanding of dynamic material failure through the analysis of hydrodynamic computer code simulations. Two-dimensional and three-dimensional computational cylinder models were analyzed using the ALE3D multi-physics computer code.

30 CFR 7.302 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... conduit box when specified. A motor assembly is comprised of one or more explosion-proof enclosures. Plane.... A metallic enclosure used as a winding compartment, conduit box, or a combination of both that... portions. Stuffing box. An entrance with a recess filled with packing material for cables extending through...

30 CFR 7.302 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... conduit box when specified. A motor assembly is comprised of one or more explosion-proof enclosures. Plane.... A metallic enclosure used as a winding compartment, conduit box, or a combination of both that... portions. Stuffing box. An entrance with a recess filled with packing material for cables extending through...

30 CFR 7.302 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... conduit box when specified. A motor assembly is comprised of one or more explosion-proof enclosures. Plane.... A metallic enclosure used as a winding compartment, conduit box, or a combination of both that... portions. Stuffing box. An entrance with a recess filled with packing material for cables extending through...

24 CFR 3280.401 - Structural load tests.

Code of Federal Regulations, 2013 CFR

2013-04-01

... sustaining its dead load plus superimposed live loads equal to 1.75 times the required live loads for a... in 1/4 design live load increments at 10-minute intervals until 1.25 times design live load plus dead... load plus dead load has been reached. Assembly failure shall be considered as design live load...

24 CFR 3280.401 - Structural load tests.

Code of Federal Regulations, 2010 CFR

2010-04-01

... sustaining its dead load plus superimposed live loads equal to 1.75 times the required live loads for a... in 1/4 design live load increments at 10-minute intervals until 1.25 times design live load plus dead... load plus dead load has been reached. Assembly failure shall be considered as design live load...

24 CFR 3280.401 - Structural load tests.

Code of Federal Regulations, 2014 CFR

2014-04-01

... sustaining its dead load plus superimposed live loads equal to 1.75 times the required live loads for a... in 1/4 design live load increments at 10-minute intervals until 1.25 times design live load plus dead... load plus dead load has been reached. Assembly failure shall be considered as design live load...

24 CFR 3280.401 - Structural load tests.

Code of Federal Regulations, 2012 CFR

2012-04-01

... sustaining its dead load plus superimposed live loads equal to 1.75 times the required live loads for a... in 1/4 design live load increments at 10-minute intervals until 1.25 times design live load plus dead... load plus dead load has been reached. Assembly failure shall be considered as design live load...

24 CFR 3280.401 - Structural load tests.

Code of Federal Regulations, 2011 CFR

2011-04-01

... sustaining its dead load plus superimposed live loads equal to 1.75 times the required live loads for a... in 1/4 design live load increments at 10-minute intervals until 1.25 times design live load plus dead... load plus dead load has been reached. Assembly failure shall be considered as design live load...

Ground Truth Collections for Explosions in Northern Fennoscandia and Russia

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

Harris, D B; Ringdal, F; Kremenetskaya, E

2003-07-28

This project is providing ground-truth information on explosions conducted at the principal mines within 500 kilometers of the ARCES station, and is assembling a seismic waveform database for these events from local and regional stations. The principal mines of interest are in northwest Russia (Khibiny Massif, Olenogorsk, Zapolyamy, and Kovdor groups) and Sweden (Malmberget, Kiruna). These mines form a natural laboratory for examining the variation of mining explosion observations with source type, since they include colocated surface and underground mines and mines conducting a variety of different shot types. In September 2002 we deployed two lines of temporary stations frommore » the Khibiny Massif through and to the north of the ARCES station. This deployment is producing data that will allow researchers to examine the variation of discriminants caused by varying source-receiver distance and the diversity of explosion types. To date, we have collected ground-truth information on 1,118 explosions in the Kola Peninsula, and have assembled waveform data for approximately 700 of these. The database includes waveforms from instruments temporarily deployed in the Khibiny Massif mines, from the Apatity network just outside of the Massif, from LVZ, KEV and ARCES, and from the stations deployed along the two lines into northern Norway. In this paper we present representative waveforms for several types of shots recorded at various regional distances. We have conducted a preliminary study of the variation of phase ratios as a function of source type. This study shows significant differences in Pd/Sn and Pd/Lg ratios for two types of mining explosions: surface ripple-fired explosions and compact underground explosions. Compact explosions are, typically, underground explosions of a few tons with only one or two short delays, and are the closest approximation to single, well-tamped explosions available in the Khibiny mines. The surface shots typically are much larger (ranging up to hundreds of tons), with many delays. The surface mine that we present results for typically also conducts several distinct shots across the mine nearly simultaneously (with a few seconds or tens of seconds). Measured phase ratios are more consistent for compact underground explosions. This consistency is an expected result given the smaller scope for shot variation in these smaller events. In addition, Pd/Lg ratios appear more stable than Pd/Sn ratios for both types of events. The most interesting result is that the compact underground explosions are richer in shear energy (i.e. having smaller P/S ratios) than their surface ripple-fired counterparts. We continue to work on an approach for identifying the principal mines to be targeted for screening at a particular station. Often, routine industrial blasts constitute a large proportion of events detected by monitoring stations close to major mining districts. Many mines may be present, and it may be a problem to determine which subset of mines is responsible for the majority of the events, and should be prime candidates for the deployment of ground-truth collection resources. Our solution to this problem entails several steps. The first is to find geographic clusters of events that may correspond to major groups of mines. For this step, we use event density maps generated from existing network catalogs. This year we examined some of the tradeoffs in generating event density maps: use of automated bulletins to produce maps vs. analyst-reviewed bulletins, and the amount of time required to produce stables maps which can be used to identify significant mines.« less

Advanced emergency openings for commercial aircraft

NASA Technical Reports Server (NTRS)

Bement, L. J.; Schimmel, M. L.

1985-01-01

Explosively actuated openings in composite panels are proposed to enhance passenger survivability within commercial aircraft by providing improvements in emergency openings, fuselage venting, and fuel dump. The concept is to embed a tiny, highly stable explosive cord in the periphery of a load-carrying composite panel; on initiation of the cord, the panel is fractured to create a well-defined opening. The panel would be installed in the sides of the fuselage for passenger egress, in the top of the fuselage for smoke venting, and in the bottoms of the fuel cells for fuel dump. Described are the concerns with the use of explosive systems, safety improvements, advantages, experimental results, and recommended approach to gain acceptance and develop this concept.

Heat resistant soy adhesives for structural wood products

Treesearch

Christopher G. Hunt; Charles Frihart; Jane O' Dell

2009-01-01

Because load-bearing bonded wood assemblies must support the structure during a fire, the limited softening and depolymerization of biobased polymers at elevated temperatures should be an advantage of biobased adhesives compared to fossil fuel-based adhesives. Because load-bearing bonded wood assemblies must support the structure during a fire, the limited softening...

Wireline tool cable head overload apparatus

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

Roessler, D.E.

1990-05-29

This patent describes a cable head adapted to support a sonde in a well borehole. It comprises: an upper end assembly adapted for connection with a cable extending into a well borehole; a lower end assembly adapted for connection to a sonde to be supported by the cable in the well borehole; yieldable means joining the upper and lower assemblies together in a fixed but yieldable relationship wherein a controllable and variable load is imparted to the cable there above during movement and variations in load on the cable are maintained within specified limits; the yieldable means further including deadmore » weight adjustable means notwithstanding variations in the dead weight of the load, and the yieldable means includes resilient means permitting movements within a desired range dependent on the adjustment thereof and bracketing a selected relative position of the upper and lower end assemblies; and an electrical contact.« less

Damage Assessment of Two-Way Bending RC Slabs Subjected to Blast Loadings

PubMed Central

Jia, Haokai; Wu, Guiying

2014-01-01

Terrorist attacks on vulnerable structures and their individual structural members may cause considerable damage and loss of life. However, the research work on response and damage analysis of single structural components, for example, a slab to blast loadings, is limited in the literature and this is necessary for assessing its vulnerability. This study investigates the blast response and damage assessment of a two-way bending reinforced concrete (RC) slab subjected to blast loadings. Numerical modeling and analysis are carried out using the commercial finite element code LS-DYNA 971. A damage assessment criterion for the two-way bending RC slab is defined based on the original and residual uniformly distributed load-carrying capacity. Parametric studies are carried out to investigate the effects of explosive weight and explosive position on the damage mode of the two-way RC slab. Some design parameters, such as the boundary conditions and the negative reinforcement steel bar length, are also discussed. The illustrated results show that the proposed criterion can apply to all failure modes. The damage assessment results are more accurate than the ones due to the conventional deformation criterion. PMID:25121134

Full-scale testing of leakage of blast waves inside a partially vented room exposed to external air blast loading

NASA Astrophysics Data System (ADS)

Codina, R.; Ambrosini, D.

2018-03-01

For the last few decades, the effects of blast loading on structures have been studied by many researchers around the world. Explosions can be caused by events such as industrial accidents, military conflicts or terrorist attacks. Urban centers have been prone to various threats including car bombs, suicide attacks, and improvised explosive devices. Partially vented constructions subjected to external blast loading represent an important topic in protective engineering. The assessment of blast survivability inside structures and the development of design provisions with respect to internal elements require the study of the propagation and leakage of blast waves inside buildings. In this paper, full-scale tests are performed to study the effects of the leakage of blast waves inside a partially vented room that is subjected to different external blast loadings. The results obtained may be useful for proving the validity of different methods of calculation, both empirical and numerical. Moreover, the experimental results are compared with those computed using the empirical curves of the US Defense report/manual UFC 3-340. Finally, results of the dynamic response of the front masonry wall are presented in terms of accelerations and an iso-damage diagram.

High-sensitivity explosives detection using dual-excitation-wavelength resonance-Raman detector

NASA Astrophysics Data System (ADS)

Yellampalle, Balakishore; McCormick, William B.; Wu, Hai-Shan; Sluch, Mikhail; Martin, Robert; Ice, Robert V.; Lemoff, Brian

2014-05-01

A key challenge for standoff explosive sensors is to distinguish explosives, with high confidence, from a myriad of unknown background materials that may have interfering spectral peaks. To meet this challenge a sensor needs to exhibit high specificity and high sensitivity in detection at low signal-to-noise ratio levels. We had proposed a Dual-Excitation- Wavelength Resonance-Raman Detector (DEWRRED) to address this need. In our previous work, we discussed various components designed at WVHTCF for a DEWRRED sensor. In this work, we show a completely assembled laboratory prototype of a DEWRRED sensor and utilize it to detect explosives from two standoff distances. The sensor system includes two novel, compact CW deep-Ultraviolet (DUV) lasers, a compact dual-band high throughput DUV spectrometer, and a highly-sensitive detection algorithm. We choose DUV excitation because Raman intensities from explosive traces are enhanced and fluorescence and solar background are not present. The DEWRRED technique exploits the excitation wavelength dependence of Raman signal strength, arising from complex interplay of resonant enhancement, self-absorption and laser penetration depth. We show measurements from >10 explosives/pre-cursor materials at different standoff distances. The sensor showed high sensitivity in explosive detection even when the signalto- noise ratio was close to one (~1.6). We measured receiver-operating-characteristics, which show a clear benefit in using the dual-excitation-wavelength technique as compared to a single-excitation-wavelength technique. Our measurements also show improved specificity using the amplitude variation information in the dual-excitation spectra.

Comparison between a typical and a simplified model for blast load-induced structural response

NASA Astrophysics Data System (ADS)

Abd-Elhamed, A.; Mahmoud, S.

2017-02-01

As explosive blasts continue to cause severe damage as well as victims in both civil and military environments. There is a bad need for understanding the behavior of structural elements to such extremely short duration dynamic loads where it is of great concern nowadays. Due to the complexity of the typical blast pressure profile model and in order to reduce the modelling and computational efforts, the simplified triangle model for blast loads profile is used to analyze structural response. This simplified model considers only the positive phase and ignores the suction phase which characterizes the typical one in simulating blast loads. The closed from solution for the equation of motion under blast load as a forcing term modelled either typical or simplified models has been derived. The considered herein two approaches have been compared using the obtained results from simulation response analysis of a building structure under an applied blast load. The computed error in simulating response using the simplified model with respect to the typical one has been computed. In general, both simplified and typical models can perform the dynamic blast-load induced response of building structures. However, the simplified one shows a remarkably different response behavior as compared to the typical one despite its simplicity and the use of only positive phase for simulating the explosive loads. The prediction of the dynamic system responses using the simplified model is not satisfactory due to the obtained larger errors as compared to the system responses obtained using the typical one.

Airfoil flutter model suspension system

NASA Technical Reports Server (NTRS)

Reed, Wilmer H. (Inventor)

1987-01-01

A wind tunnel suspension system for testing flutter models under various loads and at various angles of attack is described. The invention comprises a mounting bracket assembly affixing the suspension system to the wind tunnel, a drag-link assembly and a compound spring arrangement comprises a plunge spring working in opposition to a compressive spring so as to provide a high stiffness to trim out steady state loads and simultaneously a low stiffness to dynamic loads. By this arrangement an airfoil may be tested for oscillatory response in both plunge and pitch modes while being held under high lifting loads in a wind tunnel.

49 CFR 572.186 - Abdomen assembly.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 7 2013-10-01 2013-10-01 false Abdomen assembly. 572.186 Section 572.186... Test Dummy, 50th Percentile Adult Male § 572.186 Abdomen assembly. (a) The abdomen assembly (175-5000) is part of the dummy assembly shown in drawing 175-0000 including load sensors specified in § 572.189...

49 CFR 572.186 - Abdomen assembly.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 7 2011-10-01 2011-10-01 false Abdomen assembly. 572.186 Section 572.186... Dummy, 50th Percentile Adult Male § 572.186 Abdomen assembly. (a) The abdomen assembly (175-5000) is part of the dummy assembly shown in drawing 175-0000 including load sensors specified in § 572.189(e...

49 CFR 572.186 - Abdomen assembly.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 7 2012-10-01 2012-10-01 false Abdomen assembly. 572.186 Section 572.186... Dummy, 50th Percentile Adult Male § 572.186 Abdomen assembly. (a) The abdomen assembly (175-5000) is part of the dummy assembly shown in drawing 175-0000 including load sensors specified in § 572.189(e...

30 CFR 18.32 - Fastenings-additional requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... preclude improper assembly. (d) Holes for fastenings shall not penetrate to the interior of an explosion...-inch of stock shall be left at the center of the bottom of each hole drilled for fastenings. (f...-tensile strength fastening(s) specified by the applicant. (i) Coil-thread inserts, if used in holes for...

30 CFR 18.32 - Fastenings-additional requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... preclude improper assembly. (d) Holes for fastenings shall not penetrate to the interior of an explosion...-inch of stock shall be left at the center of the bottom of each hole drilled for fastenings. (f...-tensile strength fastening(s) specified by the applicant. (i) Coil-thread inserts, if used in holes for...

30 CFR 18.32 - Fastenings-additional requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... preclude improper assembly. (d) Holes for fastenings shall not penetrate to the interior of an explosion...-inch of stock shall be left at the center of the bottom of each hole drilled for fastenings. (f...-tensile strength fastening(s) specified by the applicant. (i) Coil-thread inserts, if used in holes for...

30 CFR 18.32 - Fastenings-additional requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... preclude improper assembly. (d) Holes for fastenings shall not penetrate to the interior of an explosion...-inch of stock shall be left at the center of the bottom of each hole drilled for fastenings. (f...-tensile strength fastening(s) specified by the applicant. (i) Coil-thread inserts, if used in holes for...

49 CFR 173.62 - Specific packaging requirements for explosives.

Code of Federal Regulations, 2014 CFR

2014-10-01

... material. No more than two segregated initiation devices per gun may be carried on the same motor vehicle... other or any other article or material carried in the vehicle; and (ii) The assembled gun packed on the... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS...

49 CFR 177.835 - Class 1 materials.

Code of Federal Regulations, 2011 CFR

2011-10-01

... wheel base of less than 184 inches; (3) Any vehicle in the combination is a cargo tank which is required... Army, Navy or Air Force of the United States Government provided the Class 1 (explosive) materials are... boards, or any similar projections. (g) No detonator assembly or booster with detonator may be...

49 CFR 177.835 - Class 1 materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... wheel base of less than 184 inches; (3) Any vehicle in the combination is a cargo tank which is required... Army, Navy or Air Force of the United States Government provided the Class 1 (explosive) materials are... boards, or any similar projections. (g) No detonator assembly or booster with detonator may be...

49 CFR 177.835 - Class 1 materials.

Code of Federal Regulations, 2010 CFR

2010-10-01

... wheel base of less than 184 inches; (3) Any vehicle in the combination is a cargo tank which is required... Army, Navy or Air Force of the United States Government provided the Class 1 (explosive) materials are... boards, or any similar projections. (g) No detonator assembly or booster with detonator may be...

49 CFR 177.835 - Class 1 materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... wheel base of less than 184 inches; (3) Any vehicle in the combination is a cargo tank which is required... Army, Navy or Air Force of the United States Government provided the Class 1 (explosive) materials are... boards, or any similar projections. (g) No detonator assembly or booster with detonator may be...

49 CFR 177.835 - Class 1 materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... wheel base of less than 184 inches; (3) Any vehicle in the combination is a cargo tank which is required... Army, Navy or Air Force of the United States Government provided the Class 1 (explosive) materials are... boards, or any similar projections. (g) No detonator assembly or booster with detonator may be...

30 CFR 7.302 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... conduit box when specified. A motor assembly is comprised of one or more explosion-proof enclosures. Plane joint. A joint comprised of two adjoining surfaces in parallel planes. Step (rabbet) joint. A joint.... A step joint may be composed of a cylindrical portion and a plane portion or of two or more plane...

Grafting C8-C16 alkyl groups altered the self-assembly and curcumin -loading properties of sodium caseinate in water.

PubMed

Zhang, Yaqiong; Yang, Puyu; Yao, Fangyi; Liu, Jie; Yu, Liangli Lucy

2018-02-01

The data presented here are related to the research article entitled "Synthesis and characterization of alkylated caseinate, and its structure-curcumin loading property relationship in water" (Zhang et al., 2018) [1]. This data article reports the detailed spectra information for 1 H NMR, 13 C NMR and UPLC-Q-TOF MS of the N-succinimidyl fatty acid esters with various alkyl chain lengths (Cn-NHSs, n = 8, 12, 14 and 16). 1 H NMR, 13 C NMR and UPLC-Q-TOF MS spectra for C16-NHS are shown as an example. Then the stacked 1 H NMR spectra of the obtained alkylated caseinates (Cn-caseinates, n = 8, 12, 14 and 16) are provided. The surface hydrophobicity index (S 0 ) of Cn-caseinates with different substitution degrees (SD) of alkyl groups is shown. Additionally, Visual appearances for the formed aqueous dispersions of curcumin-loaded native caseinate (NaCas) and Cn-caseinates self-assemblies are shown. X-ray diffraction patterns of curcumin, C16-caseinate, its physical mixture and curcumin-loaded C16-caseinate self-assemblies are examined. The re-dispersibility and short-term storage stability of the curcumin-loaded NaCas and C16-caseinate self-assemblies are also studied.

Design of responsive materials using topologically interlocked elements

NASA Astrophysics Data System (ADS)

Molotnikov, A.; Gerbrand, R.; Qi, Y.; Simon, G. P.; Estrin, Y.

2015-02-01

In this work we present a novel approach to designing responsive structures by segmentation of monolithic plates into an assembly of topologically interlocked building blocks. The particular example considered is an assembly of interlocking osteomorphic blocks. The results of this study demonstrate that the constraining force, which is required to hold the blocks together, can be viewed as a design parameter that governs the bending stiffness and the load bearing capacity of the segmented structure. In the case where the constraining forces are provided laterally using an external frame, the maximum load the assembly can sustain and its stiffness increase linearly with the magnitude of the lateral load applied. Furthermore, we show that the segmented plate with integrated shape memory wires employed as tensioning cables can act as a smart structure that changes its flexural stiffness and load bearing capacity in response to external stimuli, such as heat generated by the switching on and off an electric current.

Method for loading explosive laterally from a borehole

DOEpatents

Ricketts, Thomas E.

1981-01-01

There is provided a method for forming an in situ oil shale retort in a subterranean formation containing oil shale. At least one void is excavated in the formation, leaving zones of unfragmented formation adjacent the void. An array of main blastholes is formed in the zone of unfragmented formation and at least one explosive charge which is shaped for forming a high velocity gas jet is placed into a main blasthole with the axis of the gas jet extending transverse to the blasthole. The shaped charge is detonated for forming an auxiliary blasthole in the unfragmented formation adjacent a side wall of the main blasthole. The auxiliary blasthole extends laterally away from the main blasthole. Explosive is placed into the main blasthole and into the auxiliary blasthole and is detonated for explosively expanding formation towards the free face for forming a fragmented permeable mass of formation particles in the in situ oil shale retort.

High pressure-resistant nonincendive emulsion explosive

DOEpatents

Ruhe, Thomas C.; Rao, Pilaka P.

1994-01-01

An improved emulsion explosive composition including hollow microspheres/bulking agents having high density and high strength. The hollow microspheres/bulking agents have true particle densities of about 0.2 grams per cubic centimeter or greater and include glass, siliceous, ceramic and synthetic resin microspheres, expanded minerals, and mixtures thereof. The preferred weight percentage of hollow microspheres/bulking agents in the composition ranges from 3.0 to 10.0 A chlorinated paraffin oil, also present in the improved emulsion explosive composition, imparts a higher film strength to the oil phase in the emulsion. The emulsion is rendered nonincendive by the production of sodium chloride in situ via the decomposition of sodium nitrate, a chlorinated paraffin oil, and sodium perchlorate. The air-gap sensitivity is improved by the in situ formation of monomethylamine perchlorate from dissolved monomethylamine nitrate and sodium perchlorate. The emulsion explosive composition can withstand static pressures to 139 bars and dynamic pressure loads on the order of 567 bars.

Minimisation of the explosion shock wave load onto the occupants inside the vehicle during trinitrotoluene charge blast.

PubMed

Krzystała, Edyta; Mężyk, Arkadiusz; Kciuk, Sławomir

2016-01-01

The aim of this study was to elaborate identification method of crew overload as a result of trinitrotoluene charge explosion under the military wheeled vehicle. During the study, an experimental military ground research was carried out. The aim of this research was to verify the mine blast resistance of the prototype wheeled vehicle according to STANG 4569 as well as the anti-explosive seat. Within the work, the original methodology was elaborated along with a prototype research statement. This article presents some results of the experimental research, thanks to which there is a possibility to estimate the crew's lives being endangered in an explosion through the measurement of acceleration as well as the pressure on the chest, head and internal organs. On the basis of our acceleration results, both effectiveness and infallibility of crew protective elements along with a blast mitigation seat were verified.

Wide Area Recovery and Resiliency Program (WARRP) Knowledge Enhancement Events: Damage Assessment Building Abandonment After Action Report

DTIC Science & Technology

2012-04-17

nitrate / Fuel oil (ANFO). The explosive and the shielded CsCl sources are packaged into bombs and loaded onto a truck. The total explosive yield in...Transportation Eric Jacobs State of Colorado Laura Johnston Dewberry Carl Miller Colorado Springs OEM John Miller American Red Cross Matthew...the health effects of the contamination will be. Scenario Terrorist obtain approximately 2,300 curies of 137 Cs (CsCl), and 1.5 tons of Ammonium

Validation of a Simulation Process for Assessing the Response of a Vehicle and Its Occupants to an Explosive Threat

DTIC Science & Technology

2010-01-01

gross vehicle response; and the effects of blast mitigation material, restraint system, and seat design to the loads developed on the members of an...occupant. A Blast Event Simulation sysTem (BEST) has been developed for facilitating the easy use of the LS- DYNA solvers for conducting a...et al, 1999] for modeling blast events. In this paper the Eulerian solver of LS- DYNA is employed for simulating the soil – explosive – air

Maintenance Facilities for Ammunition, Explosives, and Toxics. Design Manual 28.3.

DTIC Science & Technology

1981-11-01

LOADING DOCK RAMP PROTECTION 28.3-2 8. FIRE PROTECTION 28.3-2 9. SECURITY 28.3-2 10. SAFETY 28.3-2 Section 2. GENERAL AMMUNITION MAINTENANCE SHOPS 28.3...protection in accordance with Section 3 1910.23c, Occupatioual Safety and Health Act Standards Manual. 5 8. FIRE PROTECTION. Fire protection for all...Volume 1, and Fire Protection Engineering, NAVFAC DM-8. 9. SECURITY. Maintenance facilities for ammunition, explosives, and I toxics shall be located so

Finite Element Analysis of M15 and M19 Mines Under Wheeled Vehicle Load

DTIC Science & Technology

2008-03-01

the plate statically. An implicit finite element option in a code called LSDYNA was used to model the pressure generated in the explosive by the...figure 4 for the M19 mines. Maximum pressure in the explosive for each mine calculated by LSDYNA code shown for a variety of plate sizes and weights...Director U.S. Army TRADOC Analysis Center-WSMR ATTN: ATRC-WSS-R White Sands Missile Range, NM 88002 Chemical Propulsion Information Agency ATTN

Shock Isolation Elements Testing for High Input Loadings. Volume III. Mechanical Shock Isolation Elements.

DTIC Science & Technology

SHOCK ABSORBERS ), (*GUIDED MISSILE SILOS, SHOCK ABSORBERS ), (*SPRINGS, (*SHOCK(MECHANICS), REDUCTION), TORSION BARS, ELASTOMERS, DAMPING, EQUATIONS OF MOTION, MODEL TESTS, TEST METHODS, NUCLEAR EXPLOSIONS, HARDENING.

The contribution of volume, technique, and load to single-repetition and total-repetition kinematics and kinetics in response to three loading schemes.

PubMed

Crewther, Blair T; Cronin, John; Keogh, Justin W L

2008-11-01

This study examined the effect of volume, technique, and load upon single-repetition and total-repetition kinematics and kinetics during three loading schemes. Eleven recreationally trained males each performed a power (8 sets of 6 repetitions at 45% of one-repetition maximum [1RM], 3-minute rest periods, explosive and ballistic movements), hypertrophy (10 sets of 10 repetitions at 75% 1RM, 2-minute rest periods, controlled movements), and maximal strength (6 sets of 4 repetitions at 88% 1RM, 4-minute rest periods, explosive intent) scheme involving squats. Examination of repetition data showed that load intensity (% 1RM) generally had a direct effect on forces, contraction times, impulses, and work (i.e., increasing with load), whereas power varied across loads (p < 0.001). However, total-repetition forces, contraction times, impulses, work, and power were all greater in the hypertrophy scheme (p < 0.001), because of the greater number of repetitions performed (volume) as well as lifting technique. No differences in total forces were found between the equal-volume power and maximal strength schemes, but the former did produce greater total contraction times, work, and power (p < 0.001), which may also be attributed to repetition and technique differences. Total impulses were the only variable greater in the maximal strength scheme (p < 0.001). Thus, the interaction of load, volume, and technique plays an important role in determining the mechanical responses (stimuli) afforded by these workouts. These findings may explain disparities cited within research, regarding the effectiveness of different loading strategies for hypertrophy, maximal strength, and power adaptation.

49 CFR 572.186 - Abdomen assembly.

Code of Federal Regulations, 2010 CFR

2010-10-01

... part of the dummy assembly shown in drawing 175-0000 including load sensors specified in § 572.189(e... measuring sensor in the abdomen as shown in Figure U5; (5) The impactor impacts the dummy's abdomen at 4.0 m... of the forces of the three abdominal load sensors, specified in 572.189(e), shall be not less than...

The SLS Stages Intertank Structural Test Assembly (STA) arrives at MSFC

NASA Image and Video Library

2018-03-06

The SLS Stages Intertank Structural Test Assembly (STA) is rolling off the NASA Pegasus Barge at the MSFC Dock enroute to the MSFC 4619 Load Test Annex test facility for qualification testing. Members of MSFC Logistics Office and Move Team members gather for last minute instructions and safety briefing before off-loading STA hardware.

Report on Transport and Loading of Explosives in the Femtosecond Tank, Room 1711A HEAF 00-010

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

Hill, D L

2002-04-25

The current OSP associated with Room 1711A located in Building 191 (HEAF) sets a limit of 5 grams Net Explosive Weight (NEW) of explosives for the room. A question was raised as to the capability of that room to withstand the overpressure created by a detonation of 5 grams NEW of explosives. Calculations were inconclusive, but indicated the wallboard would not remain intact if there was a detonation of 5 grams NEW at a distance of eight feet from the wall. These calculations did not seem logical. To verify the hypothesis, a series of experiments were conducted in the 1more » Kilogram tank. The experiments consisted of exposing a pre-built double-sided wall with the same stud spacing and drywall thickness found in the walls of Room 1711A to various amounts of explosives to create expected overpressures. The objective of this test was to prove or disprove that the walls in room 1711A could withstand a detonation of 5 grams of high explosives and to determine if larger quantities of explosives could be worked on in the room while still providing the required level of protection for personnel outside the room. Testing has verified that not only can the walls withstand a 5 gram explosion, but a 10.75 gram explosion as well. A second test was conducted using 20 grams of explosive plus a detonator. Although the inner piece of drywall cracked, the outer piece of drywall maintained its integrity, thereby confining the effects of the anticipated overpressure to the room.« less

Properties of axially loaded implant-abutment assemblies using digital holographic interferometry analysis.

PubMed

Brozović, Juraj; Demoli, Nazif; Farkaš, Nina; Sušić, Mato; Alar, Zeljko; Gabrić Pandurić, Dragana

2014-03-01

The aim of this study was to (i) obtain the force-related interferometric patterns of loaded dental implant-abutment assemblies differing in diameter and brand using digital holographic interferometry (DHI) and (ii) determine the influence of implant diameter on the extent of load-induced implant deformation by quantifying and comparing the obtained interferometric data. Experiments included five implant brands (Ankylos, Astra Tech, blueSKY, MIS and Straumann), each represented by a narrow and a wide diameter implant connected to a corresponding abutment. A quasi-Fourier setup with a 25mW helium-neon laser was used for interferometric measurements in the cervical 5mm of the implants. Holograms were recorded in two conditions per measurement: a 10N preloaded and a measuring-force loaded assembly, resulting with an interferogram. This procedure was repeated throughout the whole process of incremental axial loading, from 20N to 120N. Each measurement series was repeated three times for each assembly, with complete dismantling of the implant-loading device in between. Additional software analyses calculated deformation data. Deformations were presented as mean values±standard deviations. Statistical analysis was performed using linear mixed effects modeling in R's lme4 package. Implants exhibited linear deformation patterns. The wide diameter group had lower mean deformation values than the narrow diameter group. The diameter significantly affected the deformation throughout loading sessions. This study gained in vitro implant performance data, compared the deformations in implant bodies and numerically stated the biomechanical benefits of wider diameter implants. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

30 CFR 56.6902 - Excessive temperatures.

Code of Federal Regulations, 2012 CFR

2012-07-01

... material shall not be loaded into hot areas, such as kilns or sprung holes. (b) When blasting sulfide ores where hot holes occur that may react with explosive material in blastholes, operators shall— (1) Measure...

30 CFR 56.6902 - Excessive temperatures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... material shall not be loaded into hot areas, such as kilns or sprung holes. (b) When blasting sulfide ores where hot holes occur that may react with explosive material in blastholes, operators shall— (1) Measure...

30 CFR 56.6902 - Excessive temperatures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... material shall not be loaded into hot areas, such as kilns or sprung holes. (b) When blasting sulfide ores where hot holes occur that may react with explosive material in blastholes, operators shall— (1) Measure...

30 CFR 56.6902 - Excessive temperatures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... material shall not be loaded into hot areas, such as kilns or sprung holes. (b) When blasting sulfide ores where hot holes occur that may react with explosive material in blastholes, operators shall— (1) Measure...

30 CFR 56.6902 - Excessive temperatures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... material shall not be loaded into hot areas, such as kilns or sprung holes. (b) When blasting sulfide ores where hot holes occur that may react with explosive material in blastholes, operators shall— (1) Measure...

Reactivity and Fragmentation of Aluminum-based Structural Energetic Materials under Explosive Loading

NASA Astrophysics Data System (ADS)

Glumac, Nick; Clemenson, Michael; Guadarrama, Jose; Krier, Herman

2015-06-01

Aluminum-cased warheads have been observed to generate enhanced blast and target damage due to reactivity of the aluminum fragments with ambient air. This effect can more than double the output of a conventional warhead. The mechanism by which the aluminum reacts under these conditions remains poorly understood. We undertake a highly controlled experimental study to investigate the phenomenon of aluminum reaction under explosive loading. Experiments are conducted with Al 6061 casings and PBX-N9 explosive with a fixed charge to case mass ratio of 1:2. Results are compared to inert casings (steel), as well as to tests performed in nitrogen environments to isolate aerobic and anaerobic effects. Padded walls are used in some tests to isolate the effects of impact-induced reactions, which are found to be non-negligible. Finally, blast wave measurements and quasi-static pressure measurements are used to isolate the fraction of case reaction that is fast enough to drive the primary blast wave from the later time reaction that generates temperature and overpressure only in the late-time fireball. Fragment size distributions, including those in the micron-scale range, are collected and quantified.

Coupling crystal plasticity and phase-field damage to simulate β-HMX-based polymer-bonded explosive under shock load

NASA Astrophysics Data System (ADS)

Grilli, Nicolo; Dandekar, Akshay; Koslowski, Marisol

2017-06-01

The development of high explosive materials requires constitutive models that are able to predict the influence of microstructure and loading conditions on shock sensitivity. In this work a model at the continuum-scale for the polymer-bonded explosive constituted of β-HMX particles embedded in a Sylgard matrix is developed. It includes a Murnaghan equation of state, a crystal plasticity model, based on power-law slip rate and hardening, and a phase field damage model based on crack regularization. The temperature increase due to chemical reactions is introduced by a heat source term, which is validated using results from reactive molecular dynamics simulations. An initial damage field representing pre-existing voids and cracks is used in the simulations to understand the effect of these inhomogeneities on the damage propagation and shock sensitivity. We show the predictions of the crystal plasticity model and the effect of the HMX crystal orientation on the shock initiation and on the dissipated plastic work and damage propagation. The simulation results are validated with ultra-fast dynamic transmission electron microscopy experiments and x-ray experiments carried out at Purdue University. Membership Pending.

Suspension Device for Use with Low Temperature Refrigerator

NASA Technical Reports Server (NTRS)

Wegel, Donald C. (Inventor)

2015-01-01

A suspension device for use with a low temperature refrigeration system, such as an adiabatic demagnetization refrigerator is provided. A support ring is provided with three spring-loaded tension assemblies equally spaced about the periphery of the support ring. The tension assemblies each have a pulley, about which is entrained a band of material. Connected to this band is a ring that laterally supports a cylindrical salt pill. Undesired variations in the amount of slack in the band as the salt pill cools are compensated for by the spring loading of the tension assemblies.

Spent nuclear fuel system dynamic stability under normal conditions of transportation

DOE PAGES

Jiang, Hao; Wang, Jy-An John

2016-10-14

In a horizontal layout of a spent nuclear fuel (SNF) assembly under normal conditions of transportation (NCT), the fuel assembly’s skeleton formed by guide tubes and spacer grids is the primary load bearing structure for carrying and transferring the vibration loads within an SNF assembly. Therefore, the integrity of guide tubes and spacer grids will dictate the vibration amplitude/intensity of the fuel assembly during transport, and must be considered when designing multipurpose purpose canister (MPC) for safe SNF transport. This paper investigates the SNF assembly deformation dynamics during normal vibration mode, as well as the transient shock mode inside themore » cask during NCT. In conclusion, dynamic analyses were performed in the frequency domain to study frequency characteristic of the fuel assembly system and in the time domain to simulate the transient dynamic response of the fuel assembly.« less

Spent nuclear fuel system dynamic stability under normal conditions of transportation

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

Jiang, Hao; Wang, Jy-An John

In a horizontal layout of a spent nuclear fuel (SNF) assembly under normal conditions of transportation (NCT), the fuel assembly’s skeleton formed by guide tubes and spacer grids is the primary load bearing structure for carrying and transferring the vibration loads within an SNF assembly. Therefore, the integrity of guide tubes and spacer grids will dictate the vibration amplitude/intensity of the fuel assembly during transport, and must be considered when designing multipurpose purpose canister (MPC) for safe SNF transport. This paper investigates the SNF assembly deformation dynamics during normal vibration mode, as well as the transient shock mode inside themore » cask during NCT. In conclusion, dynamic analyses were performed in the frequency domain to study frequency characteristic of the fuel assembly system and in the time domain to simulate the transient dynamic response of the fuel assembly.« less

FUEL ASSEMBLY SHAKER TEST SIMULATION

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

Klymyshyn, Nicholas A.; Sanborn, Scott E.; Adkins, Harold E.

This report describes the modeling of a PWR fuel assembly under dynamic shock loading in support of the Sandia National Laboratories (SNL) shaker test campaign. The focus of the test campaign is on evaluating the response of used fuel to shock and vibration loads that a can occur during highway transport. Modeling began in 2012 using an LS-DYNA fuel assembly model that was first created for modeling impact scenarios. SNL’s proposed test scenario was simulated through analysis and the calculated results helped guide the instrumentation and other aspects of the testing. During FY 2013, the fuel assembly model was refinedmore » to better represent the test surrogate. Analysis of the proposed loads suggested the frequency band needed to be lowered to attempt to excite the lower natural frequencies of the fuel assembly. Despite SNL’s expansion of lower frequency components in their five shock realizations, pretest predictions suggested a very mild dynamic response to the test loading. After testing was completed, one specific shock case was modeled, using recorded accelerometer data to excite the model. Direct comparison of predicted strain in the cladding was made to the recorded strain gauge data. The magnitude of both sets of strain (calculated and recorded) are very low, compared to the expected yield strength of the Zircaloy-4 material. The model was accurate enough to predict that no yielding of the cladding was expected, but its precision at predicting micro strains is questionable. The SNL test data offers some opportunity for validation of the finite element model, but the specific loading conditions of the testing only excite the fuel assembly to respond in a limited manner. For example, the test accelerations were not strong enough to substantially drive the fuel assembly out of contact with the basket. Under this test scenario, the fuel assembly model does a reasonable job of approximating actual fuel assembly response, a claim that can be verified through direct comparison of model results to recorded test results. This does not offer validation for the fuel assembly model in all conceivable cases, such as high kinetic energy shock cases where the fuel assembly might lift off the basket floor to strike to basket ceiling. This type of nonlinear behavior was not witnessed in testing, so the model does not have test data to be validated against.a basis for validation in cases that substantially alter the fuel assembly response range. This leads to a gap in knowledge that is identified through this modeling study. The SNL shaker testing loaded a surrogate fuel assembly with a certain set of artificially-generated time histories. One thing all the shock cases had in common was an elimination of low frequency components, which reduces the rigid body dynamic response of the system. It is not known if the SNL test cases effectively bound all highway transportation scenarios, or if significantly greater rigid body motion than was tested is credible. This knowledge gap could be filled through modeling the vehicle dynamics of a used fuel conveyance, or by collecting acceleration time history data from an actual conveyance under highway conditions.« less

1.5 MW RF Load for ITER

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

Ives, Robert Lawrence; Marsden, David; Collins, George

Calabazas Creek Research, Inc. developed a 1.5 MW RF load for the ITER fusion research facility currently under construction in France. This program leveraged technology developed in two previous SBIR programs that successfully developed high power RF loads for fusion research applications. This program specifically focused on modifications required by revised technical performance, materials, and assembly specification for ITER. This program implemented an innovative approach to actively distribute the RF power inside the load to avoid excessive heating or arcing associated with constructive interference. The new design implemented materials and assembly changes required to meet specifications. Critical components were builtmore » and successfully tested during the program.« less

Contemporary training practices in elite British powerlifters: survey results from an international competition.

PubMed

Swinton, Paul A; Lloyd, Ray; Agouris, Ioannis; Stewart, Arthur

2009-03-01

The primary objective of this study was to investigate current powerlifting training methods in light of anecdotal evidence purporting increased similarity with the explosive training practices of weightlifters. The study also assessed the prevalence of contemporary training practices frequently recommended for powerlifters in the popular literature. A 20-item survey was distributed to 32 elite British powerlifters at an International competition. The subject group included multiple national, international, and commonwealth champions and record holders. Based on 2007 competition results, the average Wilks score of the group was 450.26 +/- 34.7. The response rate for the surveys was 88% (28 of 32). The survey was sectioned into 6 areas of inquiry: a) repetition speed, b) explosive training load, c) resistance materials used, d) adjunct power training methods, e) exercise selection, and f) training organization. The results demonstrate that the majority of powerlifters train with the intention to explosively lift maximal and submaximal loads (79 and 82%, respectively). Results revealed that 39% of the lifters regularly used elastic bands and that 57% incorporated chains in their training. Evidence for convergence of training practices between powerlifters and weightlifters was found when 69% of the subjects reported using the Olympic lifts or their derivatives as part of their powerlifting training. Collectively, the results demonstrate that previous notions of how powerlifters train are outdated. Contemporary powerlifters incorporate a variety of training practices that are focused on developing both explosive and maximal strength.

Self-Assembly of Supramolecular Composites under Cylindrical Confinement

NASA Astrophysics Data System (ADS)

Bai, Peter; Thorkelsson, Kari; Ercius, Peter; Xu, Ting

2014-03-01

Block copolymer (BCP) or BCP-based supramolecules are useful platforms to direct nanoparticle (NP) assemblies. However, the variety of NP assemblies is rather limited in comparison to those shown by DNA-guided approach. By subjecting supramolecular nanocomposites to 2-D cylindrical confinement afforded by anodic aluminum oxide membranes, a range of new NP assemblies such as stacked rings, and single and double helices can be readily obtained, as confirmed by TEM and TEM tomography. At low NP loadings (3 v%), the nanostructure conforms to the supramolecule morphology. However, at higher NP loadings (6-9 v%), the nanostructure deviates significantly from the morphology of supramolecular nanocomposites in bulk or in thin film, suggesting that frustrated NP packing, in addition to simple supramolecule templating, may play a significant role in the self-assembly process. The present studies demonstrate that 2-D confinement can be an effective means to tailor self-assembled NP structures and may open further opportunities to manipulate the macroscopic properties of NP assemblies.

49 CFR 171.16 - Detailed hazardous materials incident reports.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., explosion or dangerous evolution of heat (i.e., an amount of heat sufficient to be dangerous to packaging or... seal, pump, compressor, or valve; or (iii) Connection or disconnection of loading or unloading lines...

Finite element analysis of 6 large PMMA skull reconstructions: A multi-criteria evaluation approach

PubMed Central

Ridwan-Pramana, Angela; Marcián, Petr; Borák, Libor; Narra, Nathaniel; Forouzanfar, Tymour; Wolff, Jan

2017-01-01

In this study 6 pre-operative designs for PMMA based reconstructions of cranial defects were evaluated for their mechanical robustness using finite element modeling. Clinical experience and engineering principles were employed to create multiple plan options, which were subsequently computationally analyzed for mechanically relevant parameters under 50N loads: stress, strain and deformation in various components of the assembly. The factors assessed were: defect size, location and shape. The major variable in the cranioplasty assembly design was the arrangement of the fixation plates. An additional study variable introduced was the location of the 50N load within the implant area. It was found that in smaller defects, it was simpler to design a symmetric distribution of plates and under limited variability in load location it was possible to design an optimal for expected loads. However, for very large defects with complex shapes, the variability in the load locations introduces complications to the intuitive design of the optimal assembly. The study shows that it can be beneficial to incorporate multi design computational analyses to decide upon the most optimal plan for a clinical case. PMID:28609471

Finite element analysis of 6 large PMMA skull reconstructions: A multi-criteria evaluation approach.

PubMed

Ridwan-Pramana, Angela; Marcián, Petr; Borák, Libor; Narra, Nathaniel; Forouzanfar, Tymour; Wolff, Jan

2017-01-01

In this study 6 pre-operative designs for PMMA based reconstructions of cranial defects were evaluated for their mechanical robustness using finite element modeling. Clinical experience and engineering principles were employed to create multiple plan options, which were subsequently computationally analyzed for mechanically relevant parameters under 50N loads: stress, strain and deformation in various components of the assembly. The factors assessed were: defect size, location and shape. The major variable in the cranioplasty assembly design was the arrangement of the fixation plates. An additional study variable introduced was the location of the 50N load within the implant area. It was found that in smaller defects, it was simpler to design a symmetric distribution of plates and under limited variability in load location it was possible to design an optimal for expected loads. However, for very large defects with complex shapes, the variability in the load locations introduces complications to the intuitive design of the optimal assembly. The study shows that it can be beneficial to incorporate multi design computational analyses to decide upon the most optimal plan for a clinical case.

76. Neg. No. F58, Apr 13, 1930, INTERIORASSEMBLY BUILDING, BURNOFF, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

76. Neg. No. F-58, Apr 13, 1930, INTERIOR-ASSEMBLY BUILDING, BURNOFF, LOAD END OF ENAMEL OVEN - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

Hydrophobic lappaconitine loaded into iota-carrageenan by one step self-assembly.

PubMed

Sun, Wenxiu; Saldaña, Marleny D A; Zhao, Yujia; Wu, Lingling; Dong, Tungalag; Jin, Ye; Zhang, Ji

2016-02-10

New data on the loading of pH-sensitive lappaconitine loaded into iota-carrageenan (LA-ICG) is provided. This LA-ICG ionic biopolymer was prepared by one step self-assembly. The LA-ICG was characterized in terms of the loading capacity, lappaconitine (LA) releasing behavior, pH-sensitivity, and analgesic properties. Iota-carrageenan (ICG) high loading capacity reached up to 26.18% (w/w). Also, the LA, loaded with ICG, was released faster in an acidic environment than that in neutral or alkaline environments. Animal analgesic experiments showed that the LA-ICG of low molecular weight had earlier onset time and longer duration than the LA. These results suggest that the ICG of low molecular weight has great potential to achieve the synergistic effect of LA. In addition, the ICG can be used as a novel natural polymeric carrier for loading a hydrophobic alkaloid. Copyright © 2015 Elsevier Ltd. All rights reserved.

Assembly of the β-Barrel Outer Membrane Proteins in Gram-Negative Bacteria, Mitochondria, and Chloroplasts

PubMed Central

Misra, Rajeev

2012-01-01

In the last decade, there has been an explosion of publications on the assembly of β-barrel outer membrane proteins (OMPs), which carry out diverse cellular functions, including solute transport, protein secretion, and assembly of protein and lipid components of the outer membrane. Of the three outer membrane model systems—Gram-negative bacteria, mitochondria and chloroplasts—research on bacterial and mitochondrial systems has so far led the way in dissecting the β-barrel OMP assembly pathways. Many exciting discoveries have been made, including the identification of β-barrel OMP assembly machineries in bacteria and mitochondria, and potentially the core assembly component in chloroplasts. The atomic structures of all five components of the bacterial β-barrel assembly machinery (BAM) complex, except the β-barrel domain of the core BamA protein, have been solved. Structures reveal that these proteins contain domains/motifs known to facilitate protein-protein interactions, which are at the heart of the assembly pathways. While structural information has been valuable, most of our current understanding of the β-barrel OMP assembly pathways has come from genetic, molecular biology, and biochemical analyses. This paper provides a comparative account of the β-barrel OMP assembly pathways in Gram-negative bacteria, mitochondria, and chloroplasts. PMID:27335668

Assembly and intracellular delivery of quantum dot-fluorescent protein bioconjugates

NASA Astrophysics Data System (ADS)

Medintz, Igor L.; Pons, Thomas; Delehanty, James B.; Susumu, Kimihiro; Dawson, Philip E.; Mattoussi, Hedi

2008-02-01

We have previously assembled semiconductor quantum dot (QD)-based fluorescence resonance energy transfer (FRET) sensors that can specifically detect nutrients, explosives or enzymatic activity. These sensors utilized the inherent benefits of QDs as FRET donors to optimize signal transduction. In this report we functionalize QDs with the multi-subunit multi-chromophore b-phycoerythrin (b-PE) light harvesting complex using biotin-Streptavidin binding. FRET and gel electrophoretic analyses were used to characterize and confirm the QD-b-PE self-assembly. We found that immobilizing additional cell-penetrating peptides on the nanocrystal surface along with the b-PE was the key factor allowing the mixed surface QD-cargos to undergo endocytosis and intracellular delivery. Our findings on the intracellular uptake promoted by CPP were compared to those collected using microinjection technique, where QD-assemblies were delivered directly into the cytoplasm; this strategy allows bypassing of the endocytic uptake pathway. Intracellular delivery of multifunctional QD-fluorescent protein assemblies has potential applications for use in protein tracking, sensing and diagnostics.

ATP-dependent human RISC assembly pathways.

PubMed

Yoda, Mayuko; Kawamata, Tomoko; Paroo, Zain; Ye, Xuecheng; Iwasaki, Shintaro; Liu, Qinghua; Tomari, Yukihide

2010-01-01

The assembly of RNA-induced silencing complex (RISC) is a key process in small RNA-mediated gene silencing. In humans, small interfering RNAs (siRNAs) and microRNAs (miRNAs) are incorporated into RISCs containing the Argonaute (AGO) subfamily proteins Ago1-4. Previous studies have proposed that, unlike Drosophila melanogaster RISC assembly pathways, human RISC assembly is coupled with dicing and is independent of ATP. Here we show by careful reexamination that, in humans, RISC assembly and dicing are uncoupled, and ATP greatly facilitates RISC loading of small-RNA duplexes. Moreover, all four human AGO proteins show remarkably similar structural preferences for small-RNA duplexes: central mismatches promote RISC loading, and seed or 3'-mid (guide position 12-15) mismatches facilitate unwinding. All these features of human AGO proteins are highly reminiscent of fly Ago1 but not fly Ago2.

Evaluation of sulfur dioxide emissions from explosive volcanism: the 1982-1983 eruptions of Galunggung, Java, Indonesia

USGS Publications Warehouse

Bluth, G.J.S.; Casadevall, T.J.; Schnetzler, C.C.; Doiron, S.D.; Walter, Louis S.; Krueger, A.J.; Badruddin, M.

1994-01-01

Galunggung volcano, Java, awoke from a 63-year quiescence in April 1982, and erupted sporadically through January 1983. During its most violent period from April to October, the Cikasasah Volcano Observatory reported 32 large and 56 moderate to small eruptions. From April 5 through September 19 the Total Ozone Mapping Spectrometer (TOMS), carried on NASA's Nimbus-7 satellite, detected and measured 24 different sulfur dioxide clouds; an estimated 1730 kilotons (kt) of SO2 were outgassed by these explosive eruptions. The trajectories, and rapid dispersion rates, of the SO2 clouds were consistent with injection altitudes below the tropopause. An additional 300 kt of SO2 were estimated to have come from 64 smaller explosive eruptions, based on the detection limit of the TOMS instrument. For the first time, an extended period of volcanic activity was monitored by remote sensing techniques which enabled observations of both the entire SO2 clouds produced by large explosive eruptions (using TOMS), and the relatively lower levels of SO2 emissions during non-explosive outgassing (using the Correlation Spectrometer, or COSPEC). Based on COSPEC measurements from August 1982 to January 1983, and on the relationship between explosive and non-explosive degassing, approximately 400 kt of SO2 were emitted during non-explosive activity. The total sulfur dioxide outgassed from Galunggung volcano from April 1982 to January 1983 is calculated to be 2500 kt (?? 30%) from both explosive and non-explosive activity. While Galunggung added large quantities of sulfur dioxide to the atmosphere, its sporadic emissions occurred in relatively small events distributed over several months, and reached relatively low altitudes, and are unlikely to have significantly affected aerosol loading of the stratosphere in 1982 by volcanic activity. ?? 1994.

Structures to Resist the Effects of Accidental Explosions. Volume 3. Principles of Dynamic Analysis

DTIC Science & Technology

1984-06-01

multi-degree-of-freedom systems) is presented. A step-by-step numerical integration of an element’s motion under dynamic loads using the...structural arrangements; providing closures, and preventing damage to interior portions of structures due to structual motion , shock, and fragment...an element’s motion under dynamic loads utilizing the Acceleration-Impulse- Extrapolation Method or the Average Acceleration Method and design charts

Static-stress analysis of dual-axis safety vessel

NASA Astrophysics Data System (ADS)

Bultman, D. H.

1992-11-01

An 8 ft diameter safety vessel, made of HSLA-100 steel, is evaluated to determine its ability to contain the quasi-static residual pressure from a high explosive (HE) blast. The safety vessel is designed for use with the Dual-Axis Radiographic Hydrotest (DARHT) facility being developed at Los Alamos National Laboratory. A smaller confinement vessel fits inside the safety vessel and contains the actual explosion, and the safety vessel functions as a second layer of containment in the unlikely case of a confinement vessel leak. The safety vessel is analyzed as a pressure vessel based on the ASME Boiler and Pressure Vessel Code, Section 8, Division 1, and the Welding Research Council Bulletin, WRC107. Combined stresses that result from internal pressure and external loads on nozzles are calculated and compared to the allowable stresses for HSLA-100 steel. Results confirm that the shell and nozzle components are adequately designed for a static pressure of 830 psi, plus the maximum expected external loads. Shell stresses at the 'shell to nozzle' interface, produced from external loads on the nozzles, were less than 700 psi. The maximum combined stress resulting from the internal pressure plus external loads was 17,384 psi, which is significantly less than the allowable stress of 42,375 psi for HSLA-100 steel.

Deformation and Spallation of Explosive Welded Steels under Gas Gun Shock Loading

NASA Astrophysics Data System (ADS)

Yu, Ying; Li, Chao; Ma, Hong-Hao; Qi, Mei-Lan; Luo, Sheng-Nian

2018-01-01

Not Available Supported by the National Basic Research Program of China under Grant No 2014CB845904, and the National Natural Science Foundation of China under Grant Nos 11627901, 11372113 and 11672110.

MELCOR Model of the Spent Fuel Pool of Fukushima Dai-ichi Unit 4

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

Carbajo, Juan J

2012-01-01

Unit 4 of the Fukushima Dai-ichi Nuclear Power Plant suffered a hydrogen explosion at 6:00 am on March 15, 2011, exactly 3.64 days after the earthquake hit the plant and the off-site power was lost. The earthquake occurred on March 11 at 2:47 pm. Since the reactor of this Unit 4 was defueled on November 29, 2010, and all its fuel was stored in the spent fuel pool (SFP4), it was first believed that the explosion was caused by hydrogen generated by the spent fuel, in particular, by the recently discharged core. The hypothetical scenario was: power was lost, coolingmore » to the SFP4 water was lost, pool water heated/boiled, water level decreased, fuel was uncovered, hot Zircaloy reacted with steam, hydrogen was generated and accumulated above the pool, and the explosion occurred. Recent analyses of the radioisotopes present in the water of the SFP4 and underwater video indicated that this scenario did not occur - the fuel in this pool was not damaged and was never uncovered the hydrogen of the explosion was apparently generated in Unit 3 and transported through exhaust ducts that shared the same chimney with Unit 4. This paper will try to answer the following questions: Could that hypothetical scenario in the SFP4 had occurred? Could the spent fuel in the SPF4 generate enough hydrogen to produce the explosion that occurred 3.64 days after the earthquake? Given the magnitude of the explosion, it was estimated that at least 150 kg of hydrogen had to be generated. As part of the investigations of this accident, MELCOR models of the SFP4 were prepared and a series of calculations were completed. The latest version of MELCOR, version 2.1 (Ref. 1), was employed in these calculations. The spent fuel pool option for BWR fuel was selected in MELCOR. The MELCOR model of the SFP4 consists of a total of 1535 fuel assemblies out of which 548 assemblies are from the core defueled on Nov. 29, 2010, 783 assemblies are older assemblies, and 204 are new/fresh assemblies. The total decay heat of the fuel in the pool was, at the time of the accident, 2.284 MWt, of which 1.872 MWt were from the 548 assemblies of the last core discharged and 0.412 MWt were from the older 783 assemblies. These decay heat values were calculated at Oak Ridge National Laboratory using the ORIGEN2.2 code (Ref. 2) - they agree with values reported elsewhere (Ref. 3). The pool dimensions are 9.9 m x 12.2 m x 11.8 m (height), and with the water level at 11.5 m, the pool volume is 1389 m3, of which only 1240 m3 is water, as some volume is taken by the fuel and by the fuel racks. The initial water temperature of the SFP4 was assumed to be 301 K. The fuel racks are made of an aluminum alloy but are modeled in MELCOR with stainless steel and B4C. MELCOR calculations were completed for different initial water levels: 11.5 m (pool almost full, water is only 0.3 m below the top rim), 4.4577 m (top of the racks), 4.2 m, and 4.026 m (top of the active fuel). A calculation was also completed for a rapid loss of water due to a leak at the bottom of the pool, with the fuel rapidly uncovered and oxidized in air. Results of these calculations are shown in the enclosed Table I. The calculation with the initial water level at 11.5 m (full pool) takes 11 days for the water to boil down to the top of the fuel racks, 11.5 days for the fuel to be uncovered, 14.65 days to generate 150 kg of hydrogen and 19 days for the pool to be completely dry. The calculation with the initial water level at 4.4577 m, takes 1.1 days to uncover the fuel and 4.17 days to generate 150 kg of hydrogen. The calculation with the initial water level at 4.02 m takes 3.63 days to generate 150 kg of hydrogen this is exactly the time when the actual explosion occurred in Unit 4. Finally, fuel oxidation in air after the pool drained the water in 20 minutes, generates only 10 kg of hydrogen this is because very little steam is available and Zircaloy (Zr) oxidation with the oxygen of the air does not generate hydrogen. MELCOR calculated water levels and hydrogen generated in the SFP4 as a function of time for initial water levels of 4.457 m, 4.2 m and 4.02 m are shown in Figs. 1 and 2. Water levels increase at the beginning due to the expansion of the water during the heat-up from 301 K to 373 K. Boiling occurs after the water temperature reaches 373 K. The total amount of hydrogen generated is ~2000 kg, this amount includes hydrogen generated from Zr, which is the largest amount (~1580 kg), from stainless steel (~360 kg), and from B4C (~60 kg). In theory, it is possible to generate up to 3.4 kg of hydrogen per assembly (from oxidation of Zr in the fuel cladding and box), or a total of 4,525 kg from the hot 1331 assemblies stored in the SFP4. The hydrogen generated from oxidation of steel and B4C will be additional. So the answers to the questions are YES according to these MELCOR calculations, enough hydrogen (150 kg) could be generated in the SFP4 3.64 days after the earthquake to produce ...« less

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

NASA Astrophysics Data System (ADS)

Balakrishnan, Kaushik

The flow field behind chemical explosions in multiphase environments is investigated using a robust, state-of-the-art simulation strategy that accounts for the thermodynamics, gas dynamics and fluid mechanics of relevance to the problem. Focus is laid on the investigation of blast wave propagation, growth of hydrodynamic instabilities behind explosive blasts, the mixing aspects behind explosions, the effects of afterburn and its quantification, and the role played by solid particles in these phenomena. In particular, the confluence and interplay of these different physical phenomena are explored from a fundamental perspective, and applied to the problem of chemical explosions. A solid phase solver suited for the study of high-speed, two-phase flows has been developed and validated. This solver accounts for the inter-phase mass, momentum and energy transfer through empirical laws, and ensures two-way coupling between the two phases, viz. solid particles and gas. For dense flow fields, i.e., when the solid volume fraction becomes non-negligible (˜60%), the finite volume method with a Godunov type shock-capturing scheme requires modifications to account for volume fraction gradients during the computation of cell interface gas fluxes. To this end, the simulation methodology is extended with the formulation of an Eulerian gas, Lagrangian solid approach, thereby ensuring that the so developed two-phase simulation strategy can be applied for both flow conditions, dilute and dense alike. Moreover, under dense loading conditions the solid particles inevitably collide, which is accounted for in the current research effort with the use of an empirical collision/contact model from literature. Furthermore, the post-detonation flow field consists of gases under extreme temperature and pressure conditions, necessitating the use of real gas equations of state in the multiphase model. This overall simulation strategy is then extended to the investigation of chemical explosions in multiphase environments, with emphasis on the study of hydrodynamic instability growth, mixing, afterburn effects ensuing from the process, particle ignition and combustion (if reactive), dispersion, and their interaction with the vortices in the mixing layer. The post-detonation behavior of heterogeneous explosives is addressed by using three parts to the investigation. In the first part, only one-dimensional effects are considered, with the goal to assess the presently developed dense two-phase formulation. The total deliverable impulsive loading from heterogeneous explosive charges containing inert steel particles is estimated for a suite of operating parameters and compared, and it is demonstrated that heterogeneous explosive charges deliver a higher near-field impulse than homogeneous explosive charges containing the same mass of the high explosive. In the second part, three-dimensional effects such as hydrodynamic instabilities are accounted for, with the focus on characterizing the mixing layer ensuing from the detonation of heterogeneous explosive charges containing inert steel particles. It is shown that particles introduce significant amounts of hydrodynamic instabilities in the mixing layer, resulting in additional physical phenomena that play a prominent role in the flow features. In particular, the fluctuation intensities, fireball size and growth rates are augmented for heterogeneous explosions vis-a-vis homogeneous explosions, thereby demonstrating that solid particles enhance the perturbation intensities in the flow. In the third part of the investigation of heterogeneous explosions, dense, aluminized explosions are considered, and the particles are observed to burn in two phases, with an initial quenching due to the rarefaction wave, and a final quenching outside the fireball. Due to faster response time scales, smaller particles are observed to heat and accelerate more during early times, and also cool and decelerate more at late times, compared to counterpart larger particle sizes. Furthermore, the average particle velocities at late times are observed to be independent of the initial solid volume fraction in the explosive charge, as the particles eventually reach an equilibrium with the local gas. These studies have provided some crucial insights to the flow physics of dense, aluminized explosives. (Abstract shortened by UMI.)

Self-assembling segmented coiled tubing

DOEpatents

Raymond, David W.

2016-09-27

Self-assembling segmented coiled tubing is a concept that allows the strength of thick-wall rigid pipe, and the flexibility of thin-wall tubing, to be realized in a single design. The primary use is for a drillstring tubular, but it has potential for other applications requiring transmission of mechanical loads (forces and torques) through an initially coiled tubular. The concept uses a spring-loaded spherical `ball-and-socket` type joint to interconnect two or more short, rigid segments of pipe. Use of an optional snap ring allows the joint to be permanently made, in a `self-assembling` manner.

CSM docked DAP/orbital assembly bending interaction-axial case

NASA Technical Reports Server (NTRS)

Turnbull, J. F.; Jones, J. E.

1972-01-01

A digital autopilot which can provide attitude control for the entire Skylab orbital assembly using the service module reaction control jets is described. An important consideration is the potential interaction of the control system with the bending modes of the orbital assembly. Two aspects of this potential interaction were considered. The first was the possibility that bending induced rotations feeding back through the attitude sensor into the control system could produce an instability or self-sustained oscillation. The second was whether the jet activity commanded by the control system could produce excessive loads at any of the critical load points of the orbital assembly. Both aspects were studied by using analytic techniques and by running simulations on the all-digital simulator.

Explosive-actuated valve design concept that eliminates blow-by. [for the TOPS spacecraft trajectory correction propulsion subsystem

NASA Technical Reports Server (NTRS)

Hagler, R., Jr.

1974-01-01

A method of evaluating the normally open normally closed, explosive actuated valves that were selected for use in the trajectory correction propulsion subsystem of the Thermoelectric Outer Planet Spacecraft (TOPS) program is presented. The design philosophy which determined the requirements for highly reliable valves that could provide the performance capability during long duration (10 year) missions to the outer planets is discussed. The techniques that were used to fabricate the valves and manifold ten valves into an assembly with the capability of five propellant-flow initiation/isolation sequences are described. The test program, which was conducted to verify valve design requirements, is outlined and the more significant results are shown.

Centaur Standard Shroud (CSS) static limit load structural tests

NASA Technical Reports Server (NTRS)

Eastwood, C.

1975-01-01

The structural capabilities of the jettisonable metal shroud were tested and the interaction of the shroud with the Centaur stage was evaluated. A flight-configured shroud and the assemblies of the associated Centaur stage were tested for applied axial and shear loads to flight limit values. The tests included various thermal, pressure, and load conditions to verify localized strength capabilities, to evaluate subsystem performance, and to determine the aging effect on insulation system properties. The tests series verified the strength capabilities of the shroud and of all associated flight assembles. Shroud deflections were shown to remain within allowable limits so long as load sharing members were connected between the shroud and the Centaur stage.

Microbial load monitor

NASA Technical Reports Server (NTRS)

Caplin, R. S.; Royer, E. R.

1978-01-01

Attempts are made to provide a total design of a Microbial Load Monitor (MLM) system flight engineering model. Activities include assembly and testing of Sample Receiving and Card Loading Devices (SRCLDs), operator related software, and testing of biological samples in the MLM. Progress was made in assembling SRCLDs with minimal leaks and which operate reliably in the Sample Loading System. Seven operator commands are used to control various aspects of the MLM such as calibrating and reading the incubating reading head, setting the clock and reading time, and status of Card. Testing of the instrument, both in hardware and biologically, was performed. Hardware testing concentrated on SRCLDs. Biological testing covered 66 clinical and seeded samples. Tentative thresholds were set and media performance listed.

Some issues for blast from a structural reactive material solid

NASA Astrophysics Data System (ADS)

Zhang, F.

2018-07-01

Structural reactive material (SRM) is consolidated from a mixture of micro- or nanometric reactive metals and metal compounds to the mixture theoretical maximum density. An SRM can thus possess a higher energy density, relying on various exothermic reactions, and higher mechanical strength and heat resistance than that of conventional CHNO explosives. Progress in SRM solid studies is reviewed specifically as an energy source for air blast through the reaction of fine SRM fragments under explosive loading. This includes a baseline SRM solid explosion characterization, material properties of an SRM solid, and its dynamic fine fragmentation mechanisms and fragment reaction mechanisms. The overview is portrayed mainly from the author's own experimental studies combined with theoretical and numerical explanation. These advances have laid down some fundamentals for the next stage of developments.

Some issues for blast from a structural reactive material solid

NASA Astrophysics Data System (ADS)

Zhang, F.

2018-03-01

Structural reactive material (SRM) is consolidated from a mixture of micro- or nanometric reactive metals and metal compounds to the mixture theoretical maximum density. An SRM can thus possess a higher energy density, relying on various exothermic reactions, and higher mechanical strength and heat resistance than that of conventional CHNO explosives. Progress in SRM solid studies is reviewed specifically as an energy source for air blast through the reaction of fine SRM fragments under explosive loading. This includes a baseline SRM solid explosion characterization, material properties of an SRM solid, and its dynamic fine fragmentation mechanisms and fragment reaction mechanisms. The overview is portrayed mainly from the author's own experimental studies combined with theoretical and numerical explanation. These advances have laid down some fundamentals for the next stage of developments.

16 CFR 1512.14 - Requirements for fork and frame assembly.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Requirements for fork and frame assembly... assembly. The fork and frame assembly shall be tested for strength by application of a load of 890 N (200 lbf) or at least 39.5 J (350 in-lb) of energy, whichever results in the greater force, in accordance...

16 CFR 1512.14 - Requirements for fork and frame assembly.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Requirements for fork and frame assembly... assembly. The fork and frame assembly shall be tested for strength by application of a load of 890 N (200 lbf) or at least 39.5 J (350 in-lb) of energy, whichever results in the greater force, in accordance...

16 CFR 1512.14 - Requirements for fork and frame assembly.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Requirements for fork and frame assembly... assembly. The fork and frame assembly shall be tested for strength by application of a load of 890 N (200 lbf) or at least 39.5 J (350 in-lb) of energy, whichever results in the greater force, in accordance...

16 CFR 1512.14 - Requirements for fork and frame assembly.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Requirements for fork and frame assembly... assembly. The fork and frame assembly shall be tested for strength by application of a load of 890 N (200 lbf) or at least 39.5 J (350 in-lb) of energy, whichever results in the greater force, in accordance...

Hot-Spot Ignition Mechanisms for Explosives and Propellants

NASA Astrophysics Data System (ADS)

Field, J. E.; Bourne, N. K.; Palmer, S. J. P.; Walley, S. M.

1992-05-01

This paper describes the response of explosives to stress and impact and in particular the mechanisms of `hot-spot' production. Samples in the form of single crystals, powder layers, pressed pellets, gels, polymer bonded explosives (PBXs) and propellants have been studied. Techniques used include a drop-weight facility with transparent anvils which allows photography at microsecond framing intervals, an instrumented drop-weight machine, a miniaturized Hopkinson bar system for high strain rate property measurement, laser speckle for studying the deformation and fracture of PBXs, an automated system for analysing speckle patterns and heat sensitive film for recording the positions and temperatures of hot spots. Polishing and staining methods have been developed to observe the microstructure of PBXs and failure during quasi-static loading. Ignition, when it occurred, took place at local hot-spot sites. Evidence is discussed for a variety of ignition mechanisms including adiabatic shear of the explosive, adiabatic heating of trapped gases during cavity collapse, viscous flow, friction, fracture and shear of added particles and triboluminescent discharge.

Times and locations of explosions; U.S. Geological Survey 1962 field season

USGS Publications Warehouse

Roller, John C.

1962-01-01

The U.S. Geological Survey detonated 86 large charges of chemical explosives in the western United States from 6 June to 9 August 1962, in a study of crustal structure in the western United States. This Technical Letter consists of two tables containing information about these explosions. Table I gives a brief geographical description of the shotpoints, and Table II gives the date, time, location, charge size, surface elevation, and some general information about the shots. In the Remarks column (Table II), the configuration and depth of most of the charges are given. This part of the table is not complete, as some of this information has not yet been compiled. Three types of explosives were used in the program. These were: Nitramon WW, a carbo-nitrate blasting agent; Composition B, a mixture of RDX and TNT; and Tovex-Gel, a non-nitroglycerin blasting slurry. The loading, firing, and surveying was done by United ElectroDynamics, Inc., of Pasadena, California. The timing was done by the U.S. Geological Survey.

Fuze for explosive magnetohydrodynamic generator

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

Webb, G.

1976-12-23

An apparatus is examined by which high explosive charges are propelled into and detonated at the center of an MHD-X generator. The high explosive charge units are engaged and propelled by a reciprocating ram device. Detonating in each instance is achieved by striking with a firing pin a detonator charge that is in register with a booster charge, the booster charge being in detonating communication with the high explosive charge. Various safety requirements are satisfied by a spring loaded slider operating in a channel transverse and adjacent to the booster charge. The slide retains the detonator charge out of registermore » with the booster charge until a safety pin that holds the slider in place is pulled by a lanyard attached between the reciprocating ram and the safety pin. Removal of the safety pin permits the detonator charge to slide into alignment with the booster charge. Firing pin actuation is initiated by the slider at the instant the detonator charge and the booster charge come into register.« less

Ignition behavior of an aluminum-bonded explosive (ABX)

NASA Astrophysics Data System (ADS)

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

2017-01-01

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

U.S. Army Medical Department Journal, October-December 2007

DTIC Science & Technology

2007-12-01

Warrior Task Training requirements (such as weapons assembly/disassembly and functions check; individual chemical, biological , radiological, nuclear...training program focused on hands-on training in the 40 Army Warrior Tasks and 11 Battle Drills, to include advanced land navigation training; weapons ...familiarization and qualification; convoy operations; chemical, biological , radiological, nuclear and high- explosive defense; and squad and platoon

Fractional watt Vuillemier cryogenic refrigerator program engineering notebook. Volume 2: Stress analysis

NASA Technical Reports Server (NTRS)

Miller, W. S.

1974-01-01

A structural analysis performed on the 1/4-watt cryogenic refrigerator. The analysis covered the complete assembly except for the cooling jacket and mounting brackets. Maximum stresses, margin of safety, and natural frequencies were calculated for structurally loaded refrigerator components shown in assembly drawings. The stress analysis indicates that the design is satisfactory for the specified vibration environment, and the proof, burst, and normal operating loads.

75 FR 3150 - Airworthiness Directives; The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-20

... fractured front spar assembly for strut No. 3, which resulted in the loss of the strut upper link load path... of a fractured front spar assembly for strut No. 3, which resulted in the loss of the strut upper... loss of the strut upper link load path and consequent fracture of the diagonal brace, which could...

Loads Prediction Program for Accidental Explosions in Underground Munitions Storage Facilities

DTIC Science & Technology

1990-08-01

1 Loads All parameters that significantly 1417 Report Documentation Page Form ApprovedOMB No . 0704-0188 Public reporting burden for the collection...other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a...and cost of real estate to provide an adequate cushion of space around above-ground facilities. Although many governments and industries need to

Dimensional Analysis of Impulse Loading Resulting from Detonation of Shallow-Buried Charges

DTIC Science & Technology

2013-01-01

lines running along the floor, floor-bolted seats , ammunition storage racks, power-train lines, etc.). MMMS 9,3 368 Traditionally, the floor-rupture...The power of dimensional analysis is that the functional relations offered are generalized, i.e. the effect of geometrical, kinematic , ambient, loading... ejected vdet Explosive detonation velocity L/T A new quantity added which controls the time of sand-overburden bubble burst Charge/plate positioning

Molecular codes for neuronal individuality and cell assembly in the brain

PubMed Central

Yagi, Takeshi

2012-01-01

The brain contains an enormous, but finite, number of neurons. The ability of this limited number of neurons to produce nearly limitless neural information over a lifetime is typically explained by combinatorial explosion; that is, by the exponential amplification of each neuron's contribution through its incorporation into “cell assemblies” and neural networks. In development, each neuron expresses diverse cellular recognition molecules that permit the formation of the appropriate neural cell assemblies to elicit various brain functions. The mechanism for generating neuronal assemblies and networks must involve molecular codes that give neurons individuality and allow them to recognize one another and join appropriate networks. The extensive molecular diversity of cell-surface proteins on neurons is likely to contribute to their individual identities. The clustered protocadherins (Pcdh) is a large subfamily within the diverse cadherin superfamily. The clustered Pcdh genes are encoded in tandem by three gene clusters, and are present in all known vertebrate genomes. The set of clustered Pcdh genes is expressed in a random and combinatorial manner in each neuron. In addition, cis-tetramers composed of heteromultimeric clustered Pcdh isoforms represent selective binding units for cell-cell interactions. Here I present the mathematical probabilities for neuronal individuality based on the random and combinatorial expression of clustered Pcdh isoforms and their formation of cis-tetramers in each neuron. Notably, clustered Pcdh gene products are known to play crucial roles in correct axonal projections, synaptic formation, and neuronal survival. Their molecular and biological features induce a hypothesis that the diverse clustered Pcdh molecules provide the molecular code by which neuronal individuality and cell assembly permit the combinatorial explosion of networks that supports enormous processing capability and plasticity of the brain. PMID:22518100

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

Winstanley, J. L.

In August 1945, U.S. Navy Captain William Parsons served as the weaponeer aboard the Enola Gay for the mission to Hiroshima (Shelton 1988). In view of the fact that four B-29s had crashed and burned on takeoff from Tinian the night before, Captain Parsons made the decision to arm the gun-type weapon after takeoff for safety reasons (15 kilotons of TNT equivalent). Although he had no control over the success of the takeoff, he could prevent the possibility of a nuclear detonation on Tinian by controlling what we now call the nuclear explosive. As head of the Ordnance Division atmore » Los Alamos and a former gunnery officer, Captain Parsons clearly understood the role of safety in his work. The advent of the pre-assembled implosion weapon where the high explosive and nuclear materials are always in an intimate configuration meant that nuclear explosive safety became a reality at a certain point in development and production not just at the time of delivery by the military. This is the only industry where nuclear materials are intentionally put in contact with high explosives. The agency of the U.S. Government responsible for development and production of U.S. nuclear weapons is the Department of Energy (DOE) (and its predecessor agencies). This paper will be limited to nuclear explosive safety as it is currently practiced within the DOE nuclear weapons« less

16 CFR § 1512.14 - Requirements for fork and frame assembly.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Requirements for fork and frame assembly. Â... assembly. The fork and frame assembly shall be tested for strength by application of a load of 890 N (200 lbf) or at least 39.5 J (350 in-lb) of energy, whichever results in the greater force, in accordance...

An Anion-Induced Hydrothermal Oriented-Explosive Strategy for the Synthesis of Porous Upconversion Nanocrystals

PubMed Central

Qiu, Peiyu; Sun, Rongjin; Gao, Guo; Zhang, Chunlei; Chen, Bin; Yan, Naishun; Yin, Ting; Liu, Yanlei; Zhang, Jingjing; Yang, Yao; Cui, Daxiang

2015-01-01

Rare-earth (RE)-doped upconversion nanocrystals (UCNCs) are deemed as the promising candidates of luminescent nanoprobe for biological imaging and labeling. A number of methods have been used for the fabrication of UCNCs, but their assembly into porous architectures with desired size, shape and crystallographic phase remains a long-term challenging task. Here we report a facile, anion-induced hydrothermal oriented-explosive method to simultaneously control size, shape and phase of porous UCNCs. Our results confirmed the anion-induced hydrothermal oriented-explosion porous structure, size and phase transition for the cubic/hexagonal phase of NaLuF4 and NaGdF4 nanocrystals with various sizes and shapes. This general method is very important not only for successfully preparing lanthanide doped porous UCNCs, but also for clarifying the formation process of porous UCNCs in the hydrothermal system. The synthesized UCNCs were used for in vitro and in vivo CT imaging, and could be acted as the potential CT contrast agents. PMID:25767613

Attogram sensing of trinitrotoluene with a self-assembled molecular gelator.

PubMed

Kartha, Kalathil K; Babu, Sukumaran S; Srinivasan, Sampath; Ajayaghosh, Ayyappanpillai

2012-03-14

Detection of explosives is of utmost importance due to the threat to human security as a result of illegal transport and terrorist activities. Trinitrotoluene (TNT) is a widely used explosive in landmines and military operations that contaminates the environment and groundwater, posing a threat to human health. Achieving the detection of explosives at a sub-femtogram level using a molecular sensor is a challenge. Herein we demonstrate that a fluorescent organogelator exhibits superior detection capability for TNT in the gel form when compared to that in the solution state. The gel when coated on disposable paper strips detects TNT at a record attogram (ag, 10(-18) g) level (∼12 ag/cm(2)) with a detection limit of 0.23 ppq. This is a simple and low-cost method for the detection of TNT on surfaces or in aqueous solutions in a contact mode, taking advantage of the unique molecular packing of an organogelator and the associated photophysical properties.

Effect of W/O Emulsion Fuel Properties on Spray Combustion

NASA Astrophysics Data System (ADS)

Ida, Tamio; Fuchihata, Manabu; Takeda, Shuuco

This study proposes a realizable technology for an emulsion combustion method that can reduce environmental loading. This paper discusses the effect on spray combustion for W/O emulsion fuel properties with an added agent, and the ratio between water and emulsifier added to a liquid fuel. The addition of water or emulsifier to a liquid fuel affected the spray combustion by causing micro-explosions in the flame due to geometric changes in the sprayed flame and changes to the temperature distribution. Experimental results revealed that the flame length shortened by almost 40% upon the addition of the water. Furthermore, it was found that water was effective in enhancing combustion due to its promoting micro-explosions. Results also showed that when the emulsifier was added to the spray flame, the additive burned in the flame's wake, producing a bright red flame. The flame length was observed to be long as a result. The micro-explosion phenomenon, caused by emulsifier dosage differences, was observed using time-dependent images at a generated frequency and an explosion scale with a high-speed photography method. Results indicated that the micro-explosion phenomenon in the W/O emulsion combustion method effectively promoted the combustion reaction and suppressed soot formation.

A comparison study of exploding a Cu wire in air, water, and solid powders

NASA Astrophysics Data System (ADS)

Han, Ruoyu; Wu, Jiawei; Ding, Weidong; Zhou, Haibin; Qiu, Aici; Wang, Yanan

2017-11-01

In this paper, an experimental study on exploding a copper wire in air, water, incombustible powders, and energetic materials is performed. We examined the effects of the surrounding media on the explosion process and its related phenomena. Experiments were first carried out with copper wire explosions driven by microsecond timescale pulsed currents in air, water, and the half-half case. Then, the copper wires were exploded in air, water, SiO2 powders, quartz sand, NaCl powders, and energetic-material cylinders, respectively. Our experimental results indicated that the explosion process was significantly influenced by the surrounding media, resulting in noticeable differences in energy deposition, optical emission, and shock waves. In particular, incombustible powders could throttle the current flow completely when a fine wire was adopted. We also found that an air or incombustible-powder layer could drastically attenuate the shock wave generated by a wire explosion. As for energetic-material loads, obvious discrepancies were found in voltage/current waveforms from vaporization when compared with a wire explosion in air/water, which meant the metal vapor/liquid drops play a significant role in the ignition process.

TAF11 assembles RISC loading complex to enhance RNAi efficiency

PubMed Central

Liang, Chunyang; Wang, Yibing; Murota, Yukiko; Liu, Xiang; Smith, Dean; Siomi, Mikiko C.; Liu, Qinghua

2015-01-01

SUMMARY Assembly of the RNA-induced silencing complex (RISC) requires formation of the RISC loading complex (RLC), which contains Dicer-2(Dcr-2)-R2D2 complex and recruits duplex siRNA to Ago2 in Drosophila melanogaster. However, the precise composition and action mechanism of Drosophila RLC remain unclear. Here, we identified the missing factor of RLC as TATA-binding protein associated factor 11 (TAF11) by genetic screen. Although an annotated nuclear transcription factor, we found that TAF11 also associated with Dcr-2/R2D2 and localized to cytoplasmic D2 bodies. Consistent with defective RLC assembly in taf11−/− ovary extract, we reconstituted the RLC in vitro using recombinant Dcr-2-R2D2 complex, TAF11, and duplex siRNA. Furthermore, we showed that TAF11 tetramer facilitates Dcr-2-R2D2 tetramerization to enhance siRNA binding and RISC loading activities. Together, our genetic and biochemical studies define the molecular nature of Drosophila RLC and elucidate a novel cytoplasmic function of TAF11 in organizing RLC assembly to enhance RNAi efficiency. PMID:26257286

Studying Dynamic Processes of Nano-sized Objects in Liquid using Scanning Transmission Electron Microscopy.

PubMed

Hermannsdörfer, Justus; de Jonge, Niels

2017-02-05

Samples fully embedded in liquid can be studied at a nanoscale spatial resolution with Scanning Transmission Electron Microscopy (STEM) using a microfluidic chamber assembled in the specimen holder for Transmission Electron Microscopy (TEM) and STEM. The microfluidic system consists of two silicon microchips supporting thin Silicon Nitride (SiN) membrane windows. This article describes the basic steps of sample loading and data acquisition. Most important of all is to ensure that the liquid compartment is correctly assembled, thus providing a thin liquid layer and a vacuum seal. This protocol also includes a number of tests necessary to perform during sample loading in order to ensure correct assembly. Once the sample is loaded in the electron microscope, the liquid thickness needs to be measured. Incorrect assembly may result in a too-thick liquid, while a too-thin liquid may indicate the absence of liquid, such as when a bubble is formed. Finally, the protocol explains how images are taken and how dynamic processes can be studied. A sample containing AuNPs is imaged both in pure water and in saline.

Interference assembly and fretting wear analysis of hollow shaft.

PubMed

Han, Chuanjun; Zhang, Jie

2014-01-01

Fretting damage phenomenon often appears in the interference fit assembly. The finite element model of hollow shaft and shaft sleeve was established, and the equivalent stress and contact stress were computed after interference assembly. The assembly body of hollow shaft and shaft sleeve was in whirling bending load, and the contact status (sticking, sliding, and opening) and the distribution of stress along one typical contact line were computed under different loads, interferences, hollow degrees, friction coefficient, and wear quantity. Judgment formula of contact state was fixed by introducing the corrected coefficient k. The computation results showed that the "edge effect" appears in the contact surface after interference fit. The size of slip zone is unchanged along with the increase of bending load. The greater the interference value, the bigger the wear range. The hollow degree does not influence the size of stick zone but controls the position of the junction point of slip-open. Tangential contact stress increases with the friction coefficient, which has a little effect on normal contact stress. The relationship between open size and wear capacity is approximately linear.

Studying Dynamic Processes of Nano-sized Objects in Liquid using Scanning Transmission Electron Microscopy

PubMed Central

Hermannsdörfer, Justus; de Jonge, Niels

2017-01-01

Samples fully embedded in liquid can be studied at a nanoscale spatial resolution with Scanning Transmission Electron Microscopy (STEM) using a microfluidic chamber assembled in the specimen holder for Transmission Electron Microscopy (TEM) and STEM. The microfluidic system consists of two silicon microchips supporting thin Silicon Nitride (SiN) membrane windows. This article describes the basic steps of sample loading and data acquisition. Most important of all is to ensure that the liquid compartment is correctly assembled, thus providing a thin liquid layer and a vacuum seal. This protocol also includes a number of tests necessary to perform during sample loading in order to ensure correct assembly. Once the sample is loaded in the electron microscope, the liquid thickness needs to be measured. Incorrect assembly may result in a too-thick liquid, while a too-thin liquid may indicate the absence of liquid, such as when a bubble is formed. Finally, the protocol explains how images are taken and how dynamic processes can be studied. A sample containing AuNPs is imaged both in pure water and in saline. PMID:28190028

49 CFR 176.162 - Security.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 2 2012-10-01 2012-10-01 false Security. 176.162 Section 176.162 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION... Class 1 (Explosive) Materials Precautions During Loading and Unloading § 176.162 Security. A responsible...

49 CFR 176.162 - Security.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 2 2013-10-01 2013-10-01 false Security. 176.162 Section 176.162 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION... Class 1 (Explosive) Materials Precautions During Loading and Unloading § 176.162 Security. A responsible...

49 CFR 176.162 - Security.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Security. 176.162 Section 176.162 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION... Class 1 (Explosive) Materials Precautions During Loading and Unloading § 176.162 Security. A responsible...

49 CFR 176.162 - Security.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 2 2014-10-01 2014-10-01 false Security. 176.162 Section 176.162 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION... Class 1 (Explosive) Materials Precautions During Loading and Unloading § 176.162 Security. A responsible...

49 CFR 176.162 - Security.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 2 2011-10-01 2011-10-01 false Security. 176.162 Section 176.162 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION... Class 1 (Explosive) Materials Precautions During Loading and Unloading § 176.162 Security. A responsible...

49 CFR 176.160 - Protection against weather.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 2 2012-10-01 2012-10-01 false Protection against weather. 176.160 Section 176.160 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... Protection against weather. Any person loading or unloading packages containing Class 1 (explosive) materials...

49 CFR 176.160 - Protection against weather.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 2 2014-10-01 2014-10-01 false Protection against weather. 176.160 Section 176.160 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... Protection against weather. Any person loading or unloading packages containing Class 1 (explosive) materials...

49 CFR 176.160 - Protection against weather.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 2 2013-10-01 2013-10-01 false Protection against weather. 176.160 Section 176.160 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... Protection against weather. Any person loading or unloading packages containing Class 1 (explosive) materials...

49 CFR 176.160 - Protection against weather.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Protection against weather. 176.160 Section 176.160 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... Protection against weather. Any person loading or unloading packages containing Class 1 (explosive) materials...

49 CFR 176.160 - Protection against weather.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 2 2011-10-01 2011-10-01 false Protection against weather. 176.160 Section 176.160 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... Protection against weather. Any person loading or unloading packages containing Class 1 (explosive) materials...

Multilayer checkpoints for microRNA authenticity during RISC assembly.

PubMed

Kawamata, Tomoko; Yoda, Mayuko; Tomari, Yukihide

2011-09-01

MicroRNAs (miRNAs) function through the RNA-induced silencing complex (RISC), which contains an Argonaute (Ago) protein at the core. RISC assembly follows a two-step pathway: miRNA/miRNA* duplex loading into Ago, and separation of the two strands within Ago. Here we show that the 5' phosphate of the miRNA strand is essential for duplex loading into Ago, whereas the preferred 5' nucleotide of the miRNA strand and the base-pairing status in the seed region and the middle of the 3' region function as additive anchors to Ago. Consequently, the miRNA authenticity is inspected at multiple steps during RISC assembly.

RNA-based micelles: A novel platform for paclitaxel loading and delivery.

PubMed

Shu, Yi; Yin, Hongran; Rajabi, Mehdi; Li, Hui; Vieweger, Mario; Guo, Sijin; Shu, Dan; Guo, Peixuan

2018-04-28

RNA can serve as powerful building blocks for bottom-up fabrication of nanostructures for biotechnological and biomedical applications. In addition to current self-assembly strategies utilizing base pairing, motif piling and tertiary interactions, we reported for the first time the formation of RNA based micellar nanoconstruct with a cholesterol molecule conjugated onto one helical end of a branched pRNA three-way junction (3WJ) motif. The resulting amphiphilic RNA micelles consist of a hydrophilic RNA head and a covalently linked hydrophobic lipid tail that can spontaneously assemble in aqueous solution via hydrophobic interaction. Taking advantage of pRNA 3WJ branched structure, the assembled RNA micelles are capable of escorting multiple functional modules. As a proof of concept for delivery for therapeutics, Paclitaxel was loaded into the RNA micelles with significantly improved water solubility. The successful construction of the drug loaded RNA micelles was confirmed and characterized by agarose gel electrophoresis, atomic force microscopy (AFM), dynamic light scattering (DLS), and fluorescence Nile Red encapsulation assay. The estimate critical micelle formation concentration ranges from 39 nM to 78 nM. The Paclitaxel loaded RNA micelles can internalize into cancer cells and inhibit their proliferation. Further studies showed that the Paclitaxel loaded RNA micelles induced cancer cell apoptosis in a Caspase-3 dependent manner but RNA micelles alone exhibited low cytotoxicity. Finally, the Paclitaxel loaded RNA micelles targeted to tumor in vivo without accumulation in healthy tissues and organs. There is also no or very low induction of pro-inflammatory response. Therefore, multivalence, cancer cell permeability, combined with controllable assembly, low or non toxic nature, and tumor targeting are all promising features that make our pRNA micelles a suitable platform for potential drug delivery. Copyright © 2018 Elsevier B.V. All rights reserved.

Numerical Simulation of the Layer-Bylayer Destruction of Cylindrical Shells Under Explosive Loading

NASA Astrophysics Data System (ADS)

Abrosimov, N. A.; Novoseltseva, N. A.

2015-09-01

A technique of numerical analysis of the influence of reinforcement structure on the nature of the dynamic response and the process of layer-by-layer destruction of layered fiberglass cylindrical shells under an axisymmetric internal explosive loading is elaborated. The kinematic model of deformation of the laminate package is based on a nonclassical theory of shells. The geometric dependences are based on simple quadratic relations of the nonlinear theory of elasticity. The relationship between the stress and strain tensors are established by using Hooke's law for orthotropic bodies with account of degradation of stiffness characteristics of the multilayer composite due to the local destruction of some its elementary layers. An energetically consistent system of dynamic equations for composite cylindrical shells is obtained by minimizing the functional of total energy of the shell as a three-dimensional body. The numerical method for solving the formulated initial boundary-value problem is based on an explicit variational-difference scheme. Results confirming the reliability of the method used to analyze the influence of reinforcement structure on the character of destruction and the bearing capacity of pulse-loaded cylindrical shells are presented.

Plasma opening switch

DOEpatents

Savage, Mark E.; Mendel, Jr., Clifford W.

2001-01-01

A command triggered plasma opening switch assembly using an amplification stage. The assembly surrounds a coaxial transmission line and has a main plasma opening switch (POS) close to the load and a trigger POS upstream from the main POS. The trigger POS establishes two different current pathways through the assembly depended on whether it has received a trigger current pulse. The initial pathway has both POS's with plasma between their anodes and cathodes to form a short across the transmission line and isolating the load. The final current pathway is formed when the trigger POS receives a trigger current pulse which energizes its fast coil to push the conductive plasma out from between its anode and cathode, allowing the main transmission line current to pass to the fast coil of the main POS, thus pushing its plasma out the way so as to establish a direct current pathway to the load.

49 CFR 571.207 - Standard No. 207; Seating systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... standard establishes requirements for seats, their attachment assemblies, and their installation to... longitudinal direction; (c) For a seat belt assembly attached to the seat—the force specified in paragraph (a... applied simultaneously with the forces imposed on the seat by the seat belt assembly when it is loaded in...

Thermo-triggerable self-assembly comprising cinnamoyl polymeric β cyclodextrin and cinnamoyl Pluronic F127.

PubMed

Wang, Min Hui; Jeong, Jae Hyun; Kim, Jin-Chul

2016-06-01

Thermo-triggerable self-assembly was prepared by co-dissolving cinnamoyl Pluronic F127 (CinPlu) and cinnamoyl polymeric β cyclodextrin (CinPβCD) in an aqueous phase. On TEM photo, the CinPlu/CinPβCD self-assembly was 100-200nm in diameter. The specific loading of Nile red (NR) in the assembly was calculated to be 5.5% (wt NR/wt polymer), and the molar ratio of NR to βCD residue in the assembly was about 0.89:1. No significant release of NR from the assembly was observed at 10°C and 20°C. However, when the temperature was raised to 30°C, 40°C, 50°C, and 60°C, the cumulative release amount in 5min was 17%, 25%, 32%, and 52%, respectively. The specific loading of doxorubicin (DOX) in the assembly was about 6.8% (wt DOX/wt polymer) (corresponding to the molar ratio of DOX to βCD residue was about 0.41:1). The DOX release from the assembly was proportional to the temperature of release medium. NR and DOX were likely to be expelled out of the cavity of βCD residue by the interaction of the thermally hydrophobicized Pluronic F127 chain (molecular piston) and the cavity of βCD residue (cylinder). After 4h-incubation with KB cell, DOX loaded in CinPlu/CinPβCD self-assembly was found to be internalized into the cancer cell more than free DOX, observed on a confocal laser scanning microscope and a fluorescence activated cell sorter. CinPlu/CinPβCD self-assembly enhanced the in vitro anti-cancer activity of DOX against KB cell without increasing significantly the in vitro toxicity of DOX against Raw264.7 cell. Copyright © 2016 Elsevier B.V. All rights reserved.

Low profile, high load vertical rolling positioning stage

DOEpatents

Shu, Deming; Barraza, Juan

1996-01-01

A stage or support platform assembly for use in a synchrotron accurately positions equipment to be used in the beam line of the synchrotron. The support platform assembly includes an outer housing in which is disposed a lifting mechanism having a lifting platform or stage at its upper extremity on which the equipment is mounted. A worm gear assembly is located in the housing and is adapted to raise and lower a lifting shaft that is fixed to the lifting platform by an anti-binding connection. The lifting platform is moved vertically as the lifting shaft is moved vertically. The anti-binding connection prevents the shaft from rotating with respect to the platform, but does permit slight canting of the shaft with respect to the lifting platform so as to eliminate binding and wear due to possible tolerance mismatches. In order to ensure that the lifting mechanism does not move in a horizontal direction as it is moved vertically, at least three linear roller bearing assemblies are arranged around the outer-periphery of the lifting mechanism. One of the linear roller bearing assemblies can be adjusted so that the roller bearings apply a loading force against the lifting mechanism. Alternatively, a cam mechanism can be used to provide such a loading force.

Iron-based ferritin nanocore as a contrast agent.

PubMed

Sana, Barindra; Johnson, Eric; Sheah, Kenneth; Poh, Chueh Loo; Lim, Sierin

2010-09-01

Self-assembling protein cages have been exploited as templates for nanoparticle synthesis. The ferritin molecule, a protein cage present in most living systems, stores excess soluble ferrous iron in the form of an insoluble ferric complex within its cavity. Magnetic nanocores formed by loading excess iron within an engineered ferritin from Archaeoglobus fulgidus (AfFtn-AA) were studied as a potential magnetic resonance (MR) imaging contrast agent. The self-assembly characteristics of the AfFtn-AA were investigated using dynamic light scattering technique and size exclusion chromatography. Homogeneous size distribution of the assembled nanoparticles was observed using transmission electron microscopy. The magnetic properties of iron-loaded AfFtn-AA were studied using vibrating sample magnetometry. Images obtained from a 3.0 T whole-body MRI scanner showed significant brightening of T(1) images and signal loss of T(2) images with increased concentrations of iron-loaded AfFtn-AA. The analysis of the MR image intensities showed extremely high R(2) values (5300 mM(-1) s(-1)) for the iron-loaded AfFtn-AA confirming its potential as a T(2) contrast agent.

Probing Dynamic Processes in Explosives and Propellants - Science Issues

NASA Astrophysics Data System (ADS)

Moore, David

2017-06-01

Recent experiments on advanced light sources have started to unravel some of the micromechanical behavior of single crystal energetic materials, including void collapse under shock loading and inter-granular failure. These examples just scratch the surface of many extant explosives science issues, which could be elucidated with advanced XFEL-type resources. These include such diverse questions as: How do powders actually compact and what are the spatially and temporally resolved temperature and flow fields generated (especially two-phase flows)? Are there polymorphic effects (if so, how are they spatially distributed)? What are the strain fields during compaction? What happens near surfaces, especially for composite explosives? How is mechanics coupled to chemistry? What are hot spots really? I will provide some history behind these and other questions and point towards how future experiments might be designed to provide some answers.

Nanomaterial-Based Biosensors for Detection of Pesticides and Explosives

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

Wang, Jun; Lin, Yuehe

2009-01-01

In this chapter, we describe nanomaterial-based biosensors for detecting OP pesticides and explosives. CNTs and functionalized silica nanoparticles have been chosen for this study. The biosensors were combined with the flow-injection system, providing great advantages for onsite, real-time, and continuous detection of environmental pollutants such as OPs and TNT. The sensors take advantage of the electrocatalytic properties of CNTs, which makes it feasible to achieve a sensitive electrochemical detection of the products from enzymatic reactions at low potential. This approach uses a large aspect ratio of silica nanoparticles, which can be used as a carrier for loading a large amountmore » of electroactive species, such as poly(guanine), for amplified detection of explosives. These methods offer a new environmental monitoring tool for rapid, inexpensive, and highly sensitive detection of OPs or TNT compounds.« less

An investigation of a reticulated foam - perforated steel sheet combination as a blast mitigation structure

NASA Astrophysics Data System (ADS)

Nguyen, Thuy-Tien N.; Proud, William G.

2017-01-01

Explosions are one of the main causes of injuries during battles and conflicts, with improvised explosive devices (IEDs) becoming increasingly common. Blast waves produced from such explosions can inflict very complex injuries on human and serious damage to structures. Here, the interaction between blast waves and sandwich structures of reticulated foam and perforated sheets is studied using a shock tube. The level of mitigation for primary blast injuries of these structures are discussed in terms of pulse shape, pressure magnitude and impulse. Schlieren photography and other high-speed imaging were used to capture the form of the blast wave. The results show up to 95% mitigation in both pressure and impulse with the structures studied. The behaviors of these mitigating sandwich panels under two loadings, Mach 2.0 and Mach 2.6, are also discussed.

Evaluating the bending response of two osseointegrated transfemoral implant systems using 3D digital image correlation.

PubMed

Thompson, Melanie L; Backman, David; Branemark, Rickard; Mechefske, Chris K

2011-05-01

Osseointegrated transfemoral implants have been introduced as a prosthetic solution for above knee amputees. They have shown great promise, providing an alternative for individuals who could not be accommodated by conventional, socket-based prostheses; however, the occurrence of device failures is of concern. In an effort to improve the strength and longevity of the device, a new design has been proposed. This study investigates the mechanical behavior of the new taper-based assembly in comparison to the current hex-based connection for osseointegrated transfemoral implant systems. This was done to better understand the behavior of components under loading, in order to optimize the assembly specifications and improve the useful life of the system. Digital image correlation was used to measure surface strains on two assemblies during static loading in bending. This provided a means to measure deformation over the entire sample and identify critical locations as the assembly was subjected to a series of loading conditions. It provided a means to determine the effects of tightening specifications and connection geometry on the material response and mechanical behavior of the assemblies. Both osseoinegrated assemblies exhibited improved strength and mechanical performance when tightened to a level beyond the current specified tightening torque of 12 N m. This was shown by decreased strain concentration values and improved distribution of tensile strain. Increased tightening torque provides an improved connection between components regardless of design, leading to increased torque retention, decreased peak tensile strain values, and a more gradual, primarily compressive distribution of strains throughout the assembly.

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

NASA Technical Reports Server (NTRS)

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

1985-01-01

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.

Checkpoint and restart procedures for single and multi-stage structural model analysis in NASTRAN/COSMIC on a CDC 176

NASA Technical Reports Server (NTRS)

Camp, George H.; Fallon, Dennis J.

1987-01-01

The Underwater Explosions Research Division (UERD) of the David Taylor Naval Ship Research and Development Center makes extensive use of NASTRAN/COSMIC on a CDC 176 to evaluate the structural response of ship structures subjected to underwater explosion shock loadings in the time domain. As relatively new users, UERD engineers have experienced difficulties with the checkpoint/restart feature because of the vague instructions in the user manual. Working procedures for the application of the checkpoint/restart feature to the transient analysis using NASTRAN/COSMIC are illustrated.

Force to Fail Reactions With Monoethanolamine: Application to the Explosive Destruction System

DTIC Science & Technology

2014-02-01

include good solvent properties for agents, miscibility with water, noncorrosivity to stainless steel under typical EDS operating conditions, and low...50%. However, when the HD loading was ≥50%, noticeable amounts of heat were generated and white fumes were observed to form when the reagent was...heat and fumes were generated when the MEA was added to the HD. At loadings ≥ 80%, the neutralent became so viscous it could not be stirred

Dredging in Sediments Containing Munitions and Explosives of Concern (MEC)

DTIC Science & Technology

2008-08-01

bucket jaws are closed in order to “grab” a load of sediment. The loaded bucket is hoisted to the surface and side dumped into a trans- portation...digitally entering a percentage of total power (0 to 100 percent). The dredge’s hydraulic functions for the pump and hoist were controlled by solenoids...Cheryl Pollock Coastal and Hydraulics Laboratory U.S. Army Engineer Research and Development Center 3909 Halls Ferry Road Vicksburg, MS 39180-6199

Blast Load Simulator Experiments for Computational Model Validation Report 3

DTIC Science & Technology

2017-07-01

establish confidence in the results produced by the simulations. This report describes a set of replicate experiments in which a small, non - responding steel...designed to simulate blast waveforms for explosive yields up to 20,000 lb of TNT equivalent at a peak reflected pressure up to 80 psi and a peak...the pressure loading on a non - responding box-type structure at varying obliquities located in the flow of the BLS simulated blast environment for

49 CFR Appendix D to Part 173 - Test Methods for Dynamite (Explosive, Blasting, Type A)

Code of Federal Regulations, 2011 CFR

2011-10-01

... weighed to determine the percent of weight loss. 3. Test method D-3—Compression Exudation Test The entire... from the glass tube and weighed to determine the percent of weight loss. EC02MR91.067 ... assembly is placed under the compression rod, and compression is applied by means of the weight on the...

Spatial Rule-Based Modeling: A Method and Its Application to the Human Mitotic Kinetochore

PubMed Central

Ibrahim, Bashar; Henze, Richard; Gruenert, Gerd; Egbert, Matthew; Huwald, Jan; Dittrich, Peter

2013-01-01

A common problem in the analysis of biological systems is the combinatorial explosion that emerges from the complexity of multi-protein assemblies. Conventional formalisms, like differential equations, Boolean networks and Bayesian networks, are unsuitable for dealing with the combinatorial explosion, because they are designed for a restricted state space with fixed dimensionality. To overcome this problem, the rule-based modeling language, BioNetGen, and the spatial extension, SRSim, have been developed. Here, we describe how to apply rule-based modeling to integrate experimental data from different sources into a single spatial simulation model and how to analyze the output of that model. The starting point for this approach can be a combination of molecular interaction data, reaction network data, proximities, binding and diffusion kinetics and molecular geometries at different levels of detail. We describe the technique and then use it to construct a model of the human mitotic inner and outer kinetochore, including the spindle assembly checkpoint signaling pathway. This allows us to demonstrate the utility of the procedure, show how a novel perspective for understanding such complex systems becomes accessible and elaborate on challenges that arise in the formulation, simulation and analysis of spatial rule-based models. PMID:24709796

Modeling a High Explosive Cylinder Experiment

NASA Astrophysics Data System (ADS)

Zocher, Marvin A.

2017-06-01

Cylindrical assemblies constructed from high explosives encased in an inert confining material are often used in experiments aimed at calibrating and validating continuum level models for the so-called equation of state (constitutive model for the spherical part of the Cauchy tensor). Such is the case in the work to be discussed here. In particular, work will be described involving the modeling of a series of experiments involving PBX-9501 encased in a copper cylinder. The objective of the work is to test and perhaps refine a set of phenomenological parameters for the Wescott-Stewart-Davis reactive burn model. The focus of this talk will be on modeling the experiments, which turned out to be non-trivial. The modeling is conducted using ALE methodology.

Deuterium microbomb rocket propulsion

NASA Astrophysics Data System (ADS)

Winterberg, F.

2010-01-01

Large scale manned space flight within the solar system is still confronted with the solution of two problems: (1) A propulsion system to transport large payloads with short transit times between different planetary orbits. (2) A cost effective lifting of large payloads into earth orbit. For the solution of the first problem a deuterium fusion bomb propulsion system is proposed where a thermonuclear detonation wave is ignited in a small cylindrical assembly of deuterium with a gigavolt-multimegaampere proton beam, drawn from the magnetically insulated spacecraft acting in the ultrahigh vacuum of space as a gigavolt capacitor. For the solution of the second problem, the ignition is done by argon ion lasers driven by high explosives, with the lasers destroyed in the fusion explosion and becoming part of the exhaust.

Deployable centralizers

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

Grubelich, Mark C.; Su, Jiann-Cherng; Knudsen, Steven D.

2017-02-28

A centralizer assembly is disclosed that allows for the assembly to be deployed in-situ. The centralizer assembly includes flexible members that can be extended into the well bore in situ by the initiation of a gas generating device. The centralizer assembly can support a large load carrying capability compared to a traditional bow spring with little or no installation drag. Additionally, larger displacements can be produced to centralize an extremely deviated casing.

Spring loaded locator pin assembly

DOEpatents

Groll, Todd A.; White, James P.

1998-01-01

This invention deals with spring loaded locator pins. Locator pins are sometimes referred to as captured pins. This is a mechanism which locks two items together with the pin that is spring loaded so that it drops into a locator hole on the work piece.

Compressive strength after blast of sandwich composite materials

PubMed Central

Arora, H.; Kelly, M.; Worley, A.; Del Linz, P.; Fergusson, A.; Hooper, P. A.; Dear, J. P.

2014-01-01

Composite sandwich materials have yet to be widely adopted in the construction of naval vessels despite their excellent strength-to-weight ratio and low radar return. One barrier to their wider use is our limited understanding of their performance when subjected to air blast. This paper focuses on this problem and specifically the strength remaining after damage caused during an explosion. Carbon-fibre-reinforced polymer (CFRP) composite skins on a styrene–acrylonitrile (SAN) polymer closed-cell foam core are the primary composite system evaluated. Glass-fibre-reinforced polymer (GFRP) composite skins were also included for comparison in a comparable sandwich configuration. Full-scale blast experiments were conducted, where 1.6×1.3 m sized panels were subjected to blast of a Hopkinson–Cranz scaled distance of 3.02 m kg−1/3, 100 kg TNT equivalent at a stand-off distance of 14 m. This explosive blast represents a surface blast threat, where the shockwave propagates in air towards the naval vessel. Hopkinson was the first to investigate the characteristics of this explosive air-blast pulse (Hopkinson 1948 Proc. R. Soc. Lond. A 89, 411–413 (doi:10.1098/rspa.1914.0008)). Further analysis is provided on the performance of the CFRP sandwich panel relative to the GFRP sandwich panel when subjected to blast loading through use of high-speed speckle strain mapping. After the blast events, the residual compressive load-bearing capacity is investigated experimentally, using appropriate loading conditions that an in-service vessel may have to sustain. Residual strength testing is well established for post-impact ballistic assessment, but there has been less research performed on the residual strength of sandwich composites after blast. PMID:24711494

Operation greenhouse. Scientific director`s report of atomic weapon tests at Eniwetok, 1951. Annex 8.1. Blast effects on aircraft in flight. Nuclear explosion

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

Wayne, J.C.; Lehmkuhl, J.C.

1951-10-01

The primary objective of this report is to present data concerning the structural and aerodynamic loads as measured on various types of aircraft, in flight, in the vicinity of an atomic explosion. A secondary objective is to describe the instrumentation (installation, calibration, and operation) in order to provide for the future planning and conduct of similar tests. The data presented herein were obtained on Dog, Easy, and George shots of Operation Greenhouse. The airplanes used to collect these data were B-17`s, T-33`s, B-50D`s and one XB-47. These instrumented airplanes were arrayed at preassigned locations in the air space above themore » explosions. A total of approximately 250 channels of information were obtained which essentially consisted in wing bending, torsion, and shear at the root, mid-span, and outer panel; horizontal stabilizer bending at the root; normal accelerations at the nose, c.g., and tail; aerodynamic pressures at various locations on the airplanes; and temperatures experienced by various critical components of the airplane. The positions of the airplanes at the time of shock arrival were accurately determined by means of radar tracking. The measured data were correlated by means of time signals, every second, from a land based radio transmitter station, and with reference to time zero, by means of a photoelectric cell. The recorded data show that the loads produced by the shock wave were in general accord with theory. The loading experienced by an airplane while passing through the `puff` of the atomic cloud is shown to be considerably higher than that caused by the shock wave. For this reason the penetration of the puff should be avoided even by `sampling` drones.« less

Elastic-Plastic Nonlinear Response of a Space Shuttle External Tank Stringer. Part 2; Thermal and Mechanical Loadings

NASA Technical Reports Server (NTRS)

Knight, Norman F., Jr.; Warren, Jerry E.; Elliott, Kenny B.; Song, Kyongchan; Raju, Ivatury S.

2012-01-01

Elastic-plastic, large-deflection nonlinear thermo-mechanical stress analyses are performed for the Space Shuttle external tank s intertank stringers. Detailed threedimensional finite element models are developed and used to investigate the stringer s elastic-plastic response for different thermal and mechanical loading events from assembly through flight. Assembly strains caused by initial installation on an intertank panel are accounted for in the analyses. Thermal loading due to tanking was determined to be the bounding loading event. The cryogenic shrinkage caused by tanking resulted in a rotation of the intertank chord flange towards the center of the intertank, which in turn loaded the intertank stringer feet. The analyses suggest that the strain levels near the first three fasteners remain sufficiently high that a failure may occur. The analyses also confirmed that the installation of radius blocks on the stringer feet ends results in an increase in the stringer capability.

The Study of the Relationship between Probabilistic Design and Axiomatic Design Methodology. Volume 3

NASA Technical Reports Server (NTRS)

Onwubiko, Chin-Yere; Onyebueke, Landon

1996-01-01

Structural failure is rarely a "sudden death" type of event, such sudden failures may occur only under abnormal loadings like bomb or gas explosions and very strong earthquakes. In most cases, structures fail due to damage accumulated under normal loadings such as wind loads, dead and live loads. The consequence of cumulative damage will affect the reliability of surviving components and finally causes collapse of the system. The cumulative damage effects on system reliability under time-invariant loadings are of practical interest in structural design and therefore will be investigated in this study. The scope of this study is, however, restricted to the consideration of damage accumulation as the increase in the number of failed components due to the violation of their strength limits.

Smith machine counterbalance system affects measures of maximal bench press throw performance.

PubMed

Vingren, Jakob L; Buddhadev, Harsh H; Hill, David W

2011-07-01

Equipment with counterbalance weight systems is commonly used for the assessment of performance in explosive resistance exercise movements, but it is not known if such systems affect performance measures. The purpose of this study was to determine the effect of using a counterbalance weight system on measures of smith machine bench press throw performance. Ten men and 14 women (mean ± SD: age, 25 ± 4 years; height, 173 ± 10 cm; weight, 77.7 ± 18.3 kg) completed maximal smith machine bench press throws under 4 different conditions (2 × 2; counterbalance × load): with or without a counterbalance weight system and using 'light' or 'moderate' net barbell loads. Performance variables (peak force, peak velocity, and peak power) were measured using a linear accelerometer attached to the barbell. The counterbalance weight system resulted in significant (p < 0.001) reductions in measures of peak force (mean difference ± standard error: light: -112 ± 20 N; moderate: -140 ± 23 N), peak velocity (light: -0.49 ± 0.10 m·s; moderate: -0.33 ± 0.07 m·s), and peak power (light: -220 ± 43 W; moderate: -143 ± 28 W) compared with no counterbalance system for both load conditions. Load condition did not affect absolute or percentage reductions from the counterbalance weight system for any variable. In conclusion, the use of a counterbalance weight system reduces accelerometer-based performance measures for the bench press throw exercise at light and moderate loads. This reduction in measures is likely because of an increase in the external resistance during the movement, which results in a discrepancy between the manually input and the actual value for external load. A counterbalance weight system should not be used when measuring performance in explosive resistance exercises with an accelerometer.

94. Neg. No. F130, Sep 24, 1931, EXTERIOROFFICE BUILDING AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

94. Neg. No. F-130, Sep 24, 1931, EXTERIOR-OFFICE BUILDING AND ASSEMBLY BUILDING, WEST SIDE, SHOWING TRUCKS AND TRAILORS LOADED WITH NEW TRUCKS DISPLAYING SIGNS 'MORE FORDS FOR HOOVER DAM' - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

75 FR 27409 - Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model S-92A Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-17

... gearbox (MGB) filter bowl assembly with a two-piece MGB filter bowl assembly and replacing the existing mounting studs. The AD also requires inspecting the MGB lube system filters, the housing, the housing... prompted by tests indicating that an existing MGB filter bowl assembly can fail under certain loading...

29 CFR 1926.1404 - Assembly/Disassembly-general requirements (applies to all assembly and disassembly operations).

Code of Federal Regulations, 2013 CFR

2013-07-01

...'s procedures must be followed. When lifting loads without using outriggers or stabilizers, the manufacturer's procedures must be met regarding truck wedges or screws. (r) Rigging. In addition to following...(o)(3) before assembly/disassembly begins. (5) Boom and jib pick points. The point(s) of attachment...

29 CFR 1926.1404 - Assembly/Disassembly-general requirements (applies to all assembly and disassembly operations).

Code of Federal Regulations, 2012 CFR

2012-07-01

...'s procedures must be followed. When lifting loads without using outriggers or stabilizers, the manufacturer's procedures must be met regarding truck wedges or screws. (r) Rigging. In addition to following...(o)(3) before assembly/disassembly begins. (5) Boom and jib pick points. The point(s) of attachment...

29 CFR 1926.1404 - Assembly/Disassembly-general requirements (applies to all assembly and disassembly operations).

Code of Federal Regulations, 2011 CFR

2011-07-01

...'s procedures must be followed. When lifting loads without using outriggers or stabilizers, the manufacturer's procedures must be met regarding truck wedges or screws. (r) Rigging. In addition to following...(o)(3) before assembly/disassembly begins. (5) Boom and jib pick points. The point(s) of attachment...

29 CFR 1926.1404 - Assembly/Disassembly-general requirements (applies to all assembly and disassembly operations).

Code of Federal Regulations, 2014 CFR

2014-07-01

...'s procedures must be followed. When lifting loads without using outriggers or stabilizers, the manufacturer's procedures must be met regarding truck wedges or screws. (r) Rigging. In addition to following...(o)(3) before assembly/disassembly begins. (5) Boom and jib pick points. The point(s) of attachment...

Automatic box loader

DOEpatents

Eldridge, Harry H.; Jones, Robert A.; Lindner, Gordon M.; Hight, Paul H.

1976-01-01

This invention relates to a system for repetitively forming an assembly consisting of a single layer of tubes and a row of ferromagnetic armatures underlying the same, electromagnetically conveying the resulting assembly to a position overlying a storage box, and depositing the assembly in the box. The system includes means for simultaneously depositing a row of the armatures on the inclined surface of a tube retainer. Tubes then are rolled down the surface to form a single tube layer bridging the armatures. A magnet assembly carrying electromagnets respectively aligned with the armatures is advanced close to the tube layer, and in the course of this advance is angularly displaced to bring the pole pieces of the electromagnets into parallelism with the tube layer. The magnets then are energized to pick up the assembly. The loaded magnet assembly is retracted to a position overlying the box, and during this retraction is again displaced to bring the pole pieces of the electromagnets into a horizontal plane. Means are provided for inserting the loaded electromagnets in the box and then de-energizing the electromagnets to deposit the assembly therein. The system accomplishes the boxing of fragile tubes at relatively high rates. Because the tubes are boxed as separated uniform layers, subsequent unloading operations are facilitated.

Spring loaded locator pin assembly

DOEpatents

Groll, T.A.; White, J.P.

1998-03-03

This invention deals with spring loaded locator pins. Locator pins are sometimes referred to as captured pins. This is a mechanism which locks two items together with the pin that is spring loaded so that it drops into a locator hole on the work piece. 5 figs.

40 CFR 92.106 - Equipment for loading the engine.

Code of Federal Regulations, 2011 CFR

2011-07-01

... loading the locomotive engine-alternator/generator assembly electrically, and for measurement of the... angle compensation; meter(s) for measurement of the current through the load bank (a calibrated electrical shunt and voltmeter is allowed for current measurement); meter(s) to measure the voltage across...

40 CFR 92.106 - Equipment for loading the engine.

Code of Federal Regulations, 2012 CFR

2012-07-01

... loading the locomotive engine-alternator/generator assembly electrically, and for measurement of the... angle compensation; meter(s) for measurement of the current through the load bank (a calibrated electrical shunt and voltmeter is allowed for current measurement); meter(s) to measure the voltage across...

40 CFR 92.106 - Equipment for loading the engine.

Code of Federal Regulations, 2014 CFR

2014-07-01

... loading the locomotive engine-alternator/generator assembly electrically, and for measurement of the... angle compensation; meter(s) for measurement of the current through the load bank (a calibrated electrical shunt and voltmeter is allowed for current measurement); meter(s) to measure the voltage across...

40 CFR 92.106 - Equipment for loading the engine.

Code of Federal Regulations, 2013 CFR

2013-07-01

... loading the locomotive engine-alternator/generator assembly electrically, and for measurement of the... angle compensation; meter(s) for measurement of the current through the load bank (a calibrated electrical shunt and voltmeter is allowed for current measurement); meter(s) to measure the voltage across...

Numerical modelling of underwater detonation of non-ideal condensed-phase explosives

NASA Astrophysics Data System (ADS)

Schoch, Stefan; Nikiforakis, Nikolaos

2015-01-01

The interest in underwater detonation tests originated from the military, since the expansion and subsequent collapse of the explosive bubble can cause considerable damage to surrounding structures or vessels. In military applications, the explosive is typically represented as a pre-burned material under high pressure, a reasonable assumption due to the short reaction zone lengths, and complete detonation of the unreacted explosive. Hence, numerical simulations of underwater detonation tests have been primarily concerned with the prediction of target loading and the damage incurred rather than the accurate modelling of the underwater detonation process. The mining industry in contrast has adopted the underwater detonation test as a means to experimentally characterise the energy output of their highly non-ideal explosives depending on explosive type and charge configuration. This characterisation requires a good understanding of how the charge shape, pond topography, charge depth, and additional charge confinement affect the energy release, some of which can be successfully quantified with the support of accurate numerical simulations. In this work, we propose a numerical framework which is able to capture the non-ideal explosive behaviour and in addition is capable of capturing both length scales: the reaction zone and the pond domain. The length scale problem is overcome with adaptive mesh refinement, which, along with the explosive model, is validated against experimental data of various TNT underwater detonations. The variety of detonation and bubble behaviour observed in non-ideal detonations is demonstrated in a parameter study over the reactivity of TNT. A representative underwater mining test containing an ammonium-nitrate fuel-oil ratestick charge is carried out to demonstrate that the presented method can be readily applied alongside experimental underwater detonation tests.

Inter-relationships between machine squat-jump strength, force, power and 10 m sprint times in trained sportsmen.

PubMed

Harris, Nigel K; Cronin, J B; Hopkins, W G; Hansen, K T

2010-03-01

Strength and conditioning practitioners appear focussed on developing maximal strength based on the premise that it underpins explosive muscular performance. Investigation into the relationship between strength and a multitude of explosive power measures is limited though. Furthermore, the relationship of explosive force and power with functional performance is unclear. We examined the inter-relationships between maximal strength and explosive measures of force and power at different loads. Also investigated were the relationships between explosive measures and 10-m sprinting ability. Forty elite-level well-trained rugby union and league athletes performed 10-m sprints followed by bilateral concentric-only machine squat-jumps at 20 and 80%1RM. The magnitudes of the inter-relationships between groups of force measures, power measures and sprint times were interpreted using Pearson correlation coefficients, which had uncertainty (90% confidence limits) of approximately +/-0.25. Measures investigated included peak force, peak power, rate of force development, and some of Zatsiorsky's explosive measures, all expressed relative to body mass. The relationship between maximal strength and peak power was moderate at 20 %1RM (r=0.32) but trivial at 80 %1RM (r=-0.03). Practically no relationship between any of the explosive measures and 10-m sprint ability was observed (r=-0.01 to 0.06). Although correlations do not imply cause and effect, we speculate that the common practice of focussing on high levels of maximal strength in a machine squat to improve power output may be misguided. Our results also cast doubt on the efficacy of increasing explosive force and power in a machine squat-jump with the intention of improving sprint ability in well-trained athletes.

Investigating the fate of nitroaromatic (TNT) and nitramine (RDX and HMX) explosives in fractured and pristine soils.

PubMed

Douglas, Thomas A; Walsh, Marianne E; McGrath, Christian J; Weiss, Charles A

2009-01-01

Explosives compounds, known toxins, are loaded to soils on military training ranges predominantly during explosives detonation events that likely fracture soil particles. This study was conducted to investigate the fate of explosives compounds in aqueous slurries containing fractured and pristine soil particles. Three soils were crushed with a piston to emulate detonation-induced fracturing. X-ray diffraction, energy-dispersive X-ray spectrometry, gas adsorption surface area measurements, and scanning electron microscopy were used to quantify and image pristine and fractured soil particles. Aqueous batches were prepared by spiking soils with solutions containing 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 2,4-dinitrotoluene (2,4-DNT). Samples were collected over 92 d and the concentrations of the spiked explosives compounds and TNT transformation products 2-amino-4,6-dinitrotoluene (2ADNT) and 4-amino-2,6-dinitrotoluene (4ADNT) were measured. Our results suggest soil mineralogical and geochemical compositions were not changed during piston-induced fracturing but morphological differences were evident with fractured soils exhibiting more angular surfaces, more fine grained particles, and some microfracturing that is not visible in the pristine samples. TNT, 2,4-DNT, RDX, and HMX exhibited greater analyte loss over time in batch solutions containing fractured soil particles compared to their pristine counterparts. 2ADNT and 4ADNT exhibited greater concentrations in slurries containing pristine soils than in slurries containing fractured soils. Explosives compound transformation is greater in the presence of fractured soil particles than in the presence of pristine soil particles. Our results imply fractured soil particles promote explosive compound transformation and/or explosives compounds have a greater affinity for adsorption to fractured soil particle surfaces.

Dissipative particle dynamics simulation on the self-assembly and disassembly of pH-sensitive polymeric micelle with coating repair agent

NASA Astrophysics Data System (ADS)

Wang, Xiumin; Gao, Jianbang; Wang, Zhikun; Xu, Jianchang; Li, Chunling; Sun, Shuangqing; Hu, Songqing

2017-10-01

Dissipative particle dynamics (DPD) simulations were applied to investigate the coating repair agent dicyclopentadience (DCPD) in pH-sensitive micelles. The results show micelles self-assembled from triblock copolymers with strong hydrophobic interaction are not conducive to loading DCPD, and only micelles with weak interaction parameter can encapsulate DCPD well. After protonation, the structure of micelle was disassembled and DCPD beads have a stronger ability to shrink polymer chains and exposed to water. This work provides mesoscopic insight into self-assembly and disassembly of desired agent-loaded micelle, and might be useful for the design of new materials for agent delivery.

Multilayer checkpoints for microRNA authenticity during RISC assembly

PubMed Central

Kawamata, Tomoko; Yoda, Mayuko; Tomari, Yukihide

2011-01-01

MicroRNAs (miRNAs) function through the RNA-induced silencing complex (RISC), which contains an Argonaute (Ago) protein at the core. RISC assembly follows a two-step pathway: miRNA/miRNA* duplex loading into Ago, and separation of the two strands within Ago. Here we show that the 5′ phosphate of the miRNA strand is essential for duplex loading into Ago, whereas the preferred 5′ nucleotide of the miRNA strand and the base-pairing status in the seed region and the middle of the 3′ region function as additive anchors to Ago. Consequently, the miRNA authenticity is inspected at multiple steps during RISC assembly. PMID:21738221

Machine Gun Liner Bond Strength

DTIC Science & Technology

2007-08-01

explosive bonding of pure tantalum, several tantalum alloys, and Stellite 25 (an alloy of cobalt, chrome , nickel, and tungsten) in a liner...smoothly as elastic stresses increase in the plug and liner. At a certain level of displacement, the load reaches a peak and then drops sharply. The

49 CFR 176.148 - Artificial lighting.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Artificial lighting. 176.148 Section 176.148... Requirements for Class 1 (Explosive) Materials Precautions During Loading and Unloading § 176.148 Artificial lighting. Electric lights, except arc lights, are the only form of artificial lighting permitted when...

49 CFR 176.148 - Artificial lighting.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 2 2011-10-01 2011-10-01 false Artificial lighting. 176.148 Section 176.148... Requirements for Class 1 (Explosive) Materials Precautions During Loading and Unloading § 176.148 Artificial lighting. Electric lights, except arc lights, are the only form of artificial lighting permitted when...

Passive Safety Features Evaluation of KIPT Neutron Source Facility

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

Zhong, Zhaopeng; Gohar, Yousry

2016-06-01

Argonne National Laboratory (ANL) of the United States and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have cooperated on the development, design, and construction of a neutron source facility. The facility was constructed at Kharkov, Ukraine and its commissioning process is underway. It will be used to conduct basic and applied nuclear research, produce medical isotopes, and train young nuclear specialists. The facility has an electron accelerator-driven subcritical assembly. The electron beam power is 100 kW using 100 MeV electrons. Tungsten or natural uranium is the target material for generating neutrons driving the subcritical assembly. The subcritical assemblymore » is composed of WWR-M2 - Russian fuel assemblies with U-235 enrichment of 19.7 wt%, surrounded by beryllium reflector assembles and graphite blocks. The subcritical assembly is seated in a water tank, which is a part of the primary cooling loop. During normal operation, the water coolant operates at room temperature and the total facility power is ~300 KW. The passive safety features of the facility are discussed in in this study. Monte Carlo computer code MCNPX was utilized in the analyses with ENDF/B-VII.0 nuclear data libraries. Negative reactivity temperature feedback was consistently observed, which is important for the facility safety performance. Due to the design of WWR-M2 fuel assemblies, slight water temperature increase and the corresponding water density decrease produce large reactivity drop, which offset the reactivity gain by mistakenly loading an additional fuel assembly. The increase of fuel temperature also causes sufficiently large reactivity decrease. This enhances the facility safety performance because fuel temperature increase provides prompt negative reactivity feedback. The reactivity variation due to an empty fuel position filled by water during the fuel loading process is examined. Also, the loading mistakes of removing beryllium reflector assemblies and replacing them with dummy assemblies were analyzed. In all these circumstances, the reactivity change results do not cause any safety concerns.« less

Two examples of industrial applications of shock physics research

NASA Astrophysics Data System (ADS)

Sanai, Mohsen

1996-05-01

An in-depth understanding of shock physics phenomena has led to many industrial applications. Two recent applications discussed in this paper are a method for assessing explosion safety in industrial plants and a bomb-resistant luggage container for widebody aircraft. Our explosion safety assessment is based on frequent use of computer simulation of postulated accidents to model in detail the detonation of energetic materials, the formation and propagation of the resulting airblast, and the projection of fragments of known material and mass. Using a general load-damage analysis technique referred to as the pressure-impulse (PI) method, we have developed a PC-based computer algorithm that includes a continually expanding library of PI load and damage curves, which can predict and graphically display common structural damage modes and the response of humans to postulated explosion accidents. A second commercial application of shock physics discussed here is a bomb-resistant luggage container for widebody aircraft that can protect the aircraft from a terrorist bomb hidden inside the luggage. This hardened luggage container (HLC) relies on blast management and debris containment provided by a flexible flow-through blanket woven from threads made with a strong lightweight material, such as Spectra or Kevlar. This mitigation blanket forms a continuous and seamless shell around the sides of the luggage container that are parallel to the aircraft axis, leaving the two ends of the container unprotected. When an explosion occurs, the mitigation blanket expands into a nearly circular shell that contains the flying debris while directing the flow into the adjacent containers. The HLC concept has been demonstrated through full-scale experiments conducted at SRI. We believe that these two examples represent a broad class of potential industrial hazard applications of the experimental, analytical, and computational tools possessed by the shock physics community.

Quick reproduction of blast-wave flow-field properties of nuclear, TNT, and ANFO explosions

NASA Astrophysics Data System (ADS)

Groth, C. P. T.

1986-04-01

In many instances, extensive blast-wave flow-field properties are required in gasdynamics research studies of blast-wave loading and structure response, and in evaluating the effects of explosions on their environment. This report provides a very useful computer code, which can be used in conjunction with the DNA Nuclear Blast Standard subroutines and code, to quickly reconstruct complete and fairly accurate blast-wave data for almost any free-air (spherical) and surface-burst (hemispherical) nuclear, trinitrotoluene (TNT), or ammonium nitrate-fuel oil (ANFO) explosion. This code is capable of computing all of the main flow properties as functions of radius and time, as well as providing additional information regarding air viscosity, reflected shock-wave properties, and the initial decay of the flow properties just behind the shock front. Both spatial and temporal distributions of the major blast-wave flow properties are also made readily available. Finally, provisions are also included in the code to provide additional information regarding the peak or shock-front flow properties over a range of radii, for a specific explosion of interest.

"US-detonated nano bombs" facilitate targeting treatment of resistant breast cancer.

PubMed

Shi, Jinjin; Liu, Wei; Fu, Yu; Yin, Na; Zhang, Hongling; Chang, Junbiao; Zhang, Zhenzhong

2018-03-28

Reversal of drug resistance and targeted therapy are the keys but remain challenging in resistant breast cancer treatment. Herein, low frequency ultrasound detonated "nano bombs" were rationally designed and used for treatment of resistant breast cancer. For the 'nano bombs', the ammunition (Doxorubicin, DOX) was loaded into the ammunition depot (hollow mesoporous TiO 2 , MTNs), and the safety device (dsDNA) was wrapped on the surface of MTNs to avoid the unexpected DOX release. We found the "US-detonated explosive" abilities of "nano bomb" MTNs (NBMTNs), including explosive generation of ROS, explosive release of DOX, US-triggered lysosome escape and mitochondrial targeting in the in vitro and in vivo studies. More importantly, the drug resistance of MCF-7/ADR cells could be reversed via the inhibition of mitochondrial energy supply approach caused by the "explosion" of NBMTNs. Furthermore, NBMTNs combined the superior chemotherapy efficacy of DOX and potent SDT efficacy in one single platform and significantly enhanced the anticancer efficacy. Our results demonstrate an approach for reversing resistance and specific targeting of tumors using 'US-detonated nano bombs'. Copyright © 2018 Elsevier B.V. All rights reserved.

Formation of Load Parameters of Destroyed Massife in Explosion of Multicharge Composition with Separation of its Parts by Profile Inert Interval

NASA Astrophysics Data System (ADS)

Paramonov, G. P.; Mysin, A. V.; Babkin, R. S.

2017-10-01

The paper introduces construction of multicharge composition with separation of parts by the profile inert interval. On the basis of the previous researches, the pulse-forming process at explosion of the borehole multicharge taking into account the offered design is considered. The physical model for definition of reflected wavelet taking into account an increment of radius of cross section of a charging cavity and the expiration of detonation products is offered. A technique is developed for numerical modeling of gas-dynamic processes in a borehole with a change in the axial channel of a profile inert interval caused by a high-temperature flow of gaseous products of an explosion. The authors obtained the dependence of the change in mean pressure on the borehole wall on time for each of the parts of the multicharge. To blast a series of charges of the proposed design, taking into account optimization of the stress fields of neighboring charges, the delay interval is determined for a short-delayed explosion.

Novel circuits for energizing manganin stress gauges

NASA Astrophysics Data System (ADS)

Tasker, Douglas G.

2017-01-01

This paper describes the design of a novel MOSFET pulsed constant current supplies for low impedance Manganin stress gauges. The design emphasis has been on high accuracy, low noise, simple, low cost, disposable supplies that can be used to energize multiple gauges in explosive or shock experiments. The Manganin gauges used to measure stresses in detonating explosive experiments have typical resistances of 50 mΩ and are energized with pulsed currents of 50 A. Conventional pulsed, constant current supplies for these gauges are high voltage devices with outputs as high as 500 V. Common problems with the use of high voltage supplies at explosive firing sites are: erroneous signals caused by ground loops; overdrive of oscilloscopes on gauge failure; gauge signal crosstalk; cost; and errors due to changing load impedances. The new circuit corrects these issues. It is an 18-V circuit, powered by 9-V alkaline batteries, and features an optically isolated trigger, and single-point grounding. These circuits have been successfully tested at the Los Alamos National Laboratory in explosive experiments. [LA-UR-15-24819

Investigation of Fundamental Processes and Crystal-Level Defect Structures in Metal-Loaded High-Explosive Materials under Dynamic Thermo-Mechanical Loads and their Relationships to Impact Survivability of Munitions (Thrust 4, Topic J)

DTIC Science & Technology

2014-06-01

to better represent the interactions at high compression . Monodisperse systems containing 64, 128, and 256 backbone carbon atoms were studied...was observed that for the sensitive orientation only elastic compression occurred, leading to the propagation of a single wave through the material...whereas for the insensitive direction elastic compression at and immediately behind the shock front was followed by inelastic deformation, leading to

Human Health and Ecological Risk Assessment for the Operation of the Explosives Waste Treatment Facility at Site 300 of the Lawrence Livermore National Laboratory Volume 1: Report of Results

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

Gallegos, G; Daniels, J; Wegrecki, A

2006-04-24

This document contains the human health and ecological risk assessment for the Resource Recovery and Conservation Act (RCRA) permit renewal for the Explosives Waste Treatment Facility (EWTF). Volume 1 is the text of the risk assessment, and Volume 2 (provided on a compact disc) is the supporting modeling data. The EWTF is operated by the Lawrence Livermore National Laboratory (LLNL) at Site 300, which is located in the foothills between the cities of Livermore and Tracy, approximately 17 miles east of Livermore and 8 miles southwest of Tracy. Figure 1 is a map of the San Francisco Bay Area, showingmore » the location of Site 300 and other points of reference. One of the principal activities of Site 300 is to test what are known as ''high explosives'' for nuclear weapons. These are the highly energetic materials that provide the force to drive fissionable material to criticality. LLNL scientists develop and test the explosives and the integrated non-nuclear components in support of the United States nuclear stockpile stewardship program as well as in support of conventional weapons and the aircraft, mining, oil exploration, and construction industries. Many Site 300 facilities are used in support of high explosives research. Some facilities are used in the chemical formulation of explosives; others are locations where explosive charges are mechanically pressed; others are locations where the materials are inspected radiographically for such defects as cracks and voids. Finally, some facilities are locations where the machined charges are assembled before they are sent to the on-site test firing facilities, and additional facilities are locations where materials are stored. Wastes generated from high-explosives research are treated by open burning (OB) and open detonation (OD). OB and OD treatments are necessary because they are the safest methods for treating explosives wastes generated at these facilities, and they eliminate the requirement for further handling and transportation that would be required if the wastes were treated off site.« less

Human Health and Ecological Risk Assessment for the Operation of the Explosives Waste Treatment Facility at Site 300 of the Lawrence Livermore National Laboratory

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

Gallegos, G; Daniels, J; Wegrecki, A

2007-10-01

This document contains the human health and ecological risk assessment for the Resource Recovery and Conservation Act (RCRA) permit renewal for the Explosives Waste Treatment Facility (EWTF). Volume 1 is the text of the risk assessment, and Volume 2 (provided on a compact disc) is the supporting modeling data. The EWTF is operated by the Lawrence Livermore National Laboratory (LLNL) at Site 300, which is located in the foothills between the cities of Livermore and Tracy, approximately 17 miles east of Livermore and 8 miles southwest of Tracy. Figure 1 is a map of the San Francisco Bay Area, showingmore » the location of Site 300 and other points of reference. One of the principal activities of Site 300 is to test what are known as 'high explosives' for nuclear weapons. These are the highly energetic materials that provide the force to drive fissionable material to criticality. LLNL scientists develop and test the explosives and the integrated non-nuclear components in support of the United States nuclear stockpile stewardship program as well as in support of conventional weapons and the aircraft, mining, oil exploration, and construction industries. Many Site 300 facilities are used in support of high explosives research. Some facilities are used in the chemical formulation of explosives; others are locations where explosive charges are mechanically pressed; others are locations where the materials are inspected radiographically for such defects as cracks and voids. Finally, some facilities are locations where the machined charges are assembled before they are sent to the onsite test firing facilities, and additional facilities are locations where materials are stored. Wastes generated from high-explosives research are treated by open burning (OB) and open detonation (OD). OB and OD treatments are necessary because they are the safest methods for treating explosives wastes generated at these facilities, and they eliminate the requirement for further handling and transportation that would be required if the wastes were treated off site.« less

Microbial load monitor

NASA Technical Reports Server (NTRS)

Caplin, R. S.; Royer, E. R.

1977-01-01

Design analysis of a microbial load monitor system flight engineering model was presented. Checkout of the card taper and media pump system was fabricated as well as the final two incubating reading heads, the sample receiving and card loading device assembly, related sterility testing, and software. Progress in these areas was summarized.

Ecotoxicology of Explosives

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

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

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

TAF11 Assembles the RISC Loading Complex to Enhance RNAi Efficiency.

PubMed

Liang, Chunyang; Wang, Yibing; Murota, Yukiko; Liu, Xiang; Smith, Dean; Siomi, Mikiko C; Liu, Qinghua

2015-09-03

Assembly of the RNA-induced silencing complex (RISC) requires formation of the RISC loading complex (RLC), which contains the Dicer-2 (Dcr-2)-R2D2 complex and recruits duplex siRNA to Ago2 in Drosophila melanogaster. However, the precise composition and action mechanism of Drosophila RLC remain unclear. Here we identified the missing factor of RLC as TATA-binding protein-associated factor 11 (TAF11) by genetic screen. Although it is an annotated nuclear transcription factor, we found that TAF11 also associated with Dcr-2/R2D2 and localized to cytoplasmic D2 bodies. Consistent with defective RLC assembly in taf11(-/-) ovary extract, we reconstituted the RLC in vitro using the recombinant Dcr-2-R2D2 complex, TAF11, and duplex siRNA. Furthermore, we showed that TAF11 tetramer facilitates Dcr-2-R2D2 tetramerization to enhance siRNA binding and RISC loading activities. Together, our genetic and biochemical studies define the molecular nature of the Drosophila RLC and elucidate a cytoplasmic function of TAF11 in organizing RLC assembly to enhance RNAi efficiency. Copyright © 2015 Elsevier Inc. All rights reserved.

Superelastic Ball Bearings: Materials and Design to Avoid Mounting and Dismounting Brinell Damage in an Inaccessible Press-Fit Application-. I ; Design Approach

NASA Technical Reports Server (NTRS)

Dellacorte, Christopher; Howard, S. Adam

2015-01-01

Ball bearings require proper fit and installation into machinery structures (onto shafts and into bearing housings) to ensure optimal performance. For some applications, both the inner and outer race must be mounted with an interference fit and care must be taken during assembly and disassembly to avoid placing heavy static loads between the balls and races otherwise Brinell dent type damage can occur. In this paper, a highly dent resistant superelastic alloy, 60NiTi, is considered for rolling element bearing applications that encounter excessive static axial loading during assembly or disassembly. A small (R8) ball bearing is designed for an application in which access to the bearing races to apply disassembly tools is precluded. First Principles analyses show that by careful selection of materials, raceway curvature and land geometry, a bearing can be designed that allows blind assembly and disassembly without incurring raceway damage due to ball denting. Though such blind assembly applications are uncommon, the availability of bearings with unusually high static load capability may enable more such applications with additional benefits, especially for miniature bearings.

Pushrod assembly

DOEpatents

Potter, J.D.

1984-03-30

A pushrod assembly including a carriage mounted on a shaft for movement therealong and carrying a pushrod engageable with a load to be moved is described. A magnet is mounted on a supporting bracket for movement along such shaft. Means are provided for adjustably spacing magnet away from the carriage to obtain a selected magnetic attractive or coupling force therebetween. Movement of the supporting bracket and the magnet carried thereby pulls the carriage along with it until the selected magnetic force is exceeded by a resistance load acting on the carriage.