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Evaluation of few-view reconstruction parameters for illicit substance detection using fast-neutron transmission spectroscopy

Description: We have evaluated the performance of the Maximum Likelihood algebraic reconstruction algorithm for the case of a few projections and for relatively coarse projection and pixel resolution. Ibis evaluation was done using receiver operator curves obtained from the fast neutron transmission spectroscopy system operated in a mode to detect explosives in luggage. The results show that increasing the number of projection angles is more important than increasing the projection resolution, the reconstructed pixel resolution, or the number of iterations in the Maximum Likelihood algorithm. A 100% detection efficiency with essentially no false positives is possible for a square block of RDX explosive, a projection resolution of 2 cm, a reconstructed pixel size of 2 {times} 2 cm, and five projection angles. For rectangular shaped explosives more angles are required obtain the same system performance.
Date: December 31, 1995
Creator: Fink, C.L.; Humm, P.G. & Micklich, B.J.
Partner: UNT Libraries Government Documents Department

Advances in associated-particle sealed-tube neutron probe diagnostics for substance detection

Description: The development and investigation of a small associated-particle sealed-tube neutron generator (APSTNG) shows potential to allow the associated-particle diagnostic method to be moved out of the laboratory into field applications. The APSTNG interrogates the inspected object with 14-MeV neutrons generated from the deuterium-tritium reaction and detects the alpha-particle associated with each neutron inside a cone encompassing the region of interest. Gamma-ray spectra of resulting neutron reactions identify many nuclides. Flight-times determined from detection times of the gamma-rays and alpha-particles can yield a separate coarse tomographic image of each identified nuclide, from a single orientation. Chemical substances are identified by comparing relative spectral line intensities with ratios of elements in reference compounds. The high-energy neutrons and gamma-rays penetrate large objects and dense materials. Generally no collimators or radiation shielding are needed. Proof-of-concept laboratory experiments have been successfully performed for simulated nuclear, chemical warfare, and conventional munitions. Most recently, inspection applications have been investigated for radioactive waste characterization, presence of cocaine in propane tanks, and uranium and plutonium smuggling. Based on lessons learned with the present APSTNG system, an advanced APSTNG tube (along with improved high voltage supply and control units) is being designed and fabricated that will be transportable and rugged, yield a substantial neutron output increase, and provide sufficiently improved lifetime to allow operation at more than an order of magnitude increase in neutron flux.
Date: July 1, 1995
Creator: Rhodes, E.; Dickerman, C.E. & Frey, M.
Partner: UNT Libraries Government Documents Department

Insensitive explosive

Description: This invention relates to the field of chemistry and, more particularly, to explosives. This invention is the result of a contract with the Department of Energy (Contract No. W-7405-ENG-36). It is desirable to use explosives in weapons and other applications which are less sensitive than the common explosives RDX, TNT, and HMX, since there have been catastrophic explosions of munitions which use these compounds. In preliminary characterization and sensitivity testing, it has been found that 3-amino-5-nitro-1,2,4-triazole (ANTA) is a promising insensitive high explosive. This report details the safety, production, and physical properties of ANTA.
Date: December 31, 1991
Creator: Lee, Kien-yin & Storm, C.B.
Partner: UNT Libraries Government Documents Department

Inert plug formation in the DDT of granular energetic materials

Description: A mechanism is proposed to explain the {open_quotes}plugs{close_quotes} that have been observed in deflagration-to-detonation transition (DDT) of granular explosives. Numerical simulations are performed that demonstrate the proposed mechanism. Observed trends are reproduced.
Date: September 1, 1995
Creator: Son, S.F.; Asay, B.W. & Bdzil, J.B.
Partner: UNT Libraries Government Documents Department

Field screening of soils contaminated with explosives using ion mobility spectrometry

Description: Soils contaminated with explosives constitute a problem at DOE facilities and Army installations. Because explosives in soil are often heterogeneously distributed and require high density sampling, field screening is essential to characterize sites more quickly, economically and accurately. Current immunoassay and colorimetric field screening procedures have proven useful, but have significant per sample costs and limited throughput. At present, several field screening are available for TNT in soil, three procedures for RDX, and one procedure for 2,4-DNTand ammonium picrate/picric acid (AP/PA). Ion mobility spectrometry (IMS) has been used to detect explosives in air at ppt levels, but limited work has been done to apply the technique to quantify explosives in soils. The objective of this study has been to evaluate the utility of IMS as a screening technique for quantifying explosive residues in soils.
Date: September 1, 1996
Creator: Crockett, A.B.; Atkinson, D.A. & Jenkins, T.F.
Partner: UNT Libraries Government Documents Department

LLNL Small-Scale Friction sensitivity (BAM) Test

Description: Small-scale safety testing of explosives, propellants and other energetic materials, is done to determine their sensitivity to various stimuli including friction, static spark, and impact. Testing is done to discover potential handling problems for either newly synthesized materials of unknown behavior, or materials that have been stored for long periods of time. This report describes the existing {open_quotes}BAM{close_quotes} Small-Scale Friction Test, and the methods used to determine the friction sensitivity pertinent to handling energetic materials. The accumulated data for the materials tested is not listed here - that information is in a database. Included is, however, a short list of (1) materials that had an unusual response, and (2), a few {open_quotes}standard{close_quotes} materials representing the range of typical responses usually seen.
Date: June 1, 1996
Creator: Simpson, L.R. & Foltz, M.F.
Partner: UNT Libraries Government Documents Department

Molten salt destruction of base hydrolysate

Description: There is a great need for alternatives to open burn/open detonation of explosives and propellants from dismantled munitions. LANL has investigated the use of base hydrolysis for the demilitarization of explosives. Hydrolysates of Comp B, Octol, Tritonal, and PBXN-109 were processed in the pilot molten salt unit (in building 191). NOx and CO emissions were found to be low, except for CO from PBXN-109 processing. This report describes experimental results of the destruction of the base hydrolysates.
Date: October 1, 1996
Creator: Watkins, B.E.; Kanna, R.L.; Chambers, R.D.; Upadhye, R.S. & Promeda, C.O.
Partner: UNT Libraries Government Documents Department

Molten salt destruction of energetic material wastes as an alternative to open burning

Description: The Lawrence Livermore National Laboratory in conjunction with the Energetic Materials Center (a partnership of Lawrence Livermore and Sandia National Laboratories), is developing methods for the safe and environmentally sound destruction of explosives and propellants as a part of the Laboratory`s ancillary demilitarization mission. As a result of the end of the Cold War and the shift in emphasis to a smaller stockpile, many munitions, both conventional and nuclear, are scheduled for retirement and rapid dismantlement and demilitarization. major components of these munitions are the explosives and propellants, or energetic materials. The Department of Energy has thousands of pounds of energetic materials which result from dismantlement operations at the Pantex Plant. The Department of Defense has several hundred million pounds of energetic materials in its demilitarization inventory, with millions more added each year.
Date: September 8, 1994
Creator: Upadhye, R.S.; Brummond, W.A.; Pruneda, C.O. & Watkins, B.E.
Partner: UNT Libraries Government Documents Department

Multispectral image fusion for detecting land mines

Description: This report details a system which fuses information contained in registered images from multiple sensors to reduce the effects of clutter and improve the ability to detect surface and buried land mines. The sensor suite currently consists of a camera that acquires images in six bands (400nm, 500nm, 600nm, 700nm, 800nm and 900nm). Past research has shown that it is extremely difficult to distinguish land mines from background clutter in images obtained from a single sensor. It is hypothesized, however, that information fused from a suite of various sensors is likely to provide better detection reliability, because the suite of sensors detects a variety of physical properties that are more separable in feature space. The materials surrounding the mines can include natural materials (soil, rocks, foliage, water, etc.) and some artifacts.
Date: April 1, 1995
Creator: Clark, G.A.; Sengupta, S.K.; Aimonetti, W.D.; Roeske, F.; Donetti, J.G.; Fields, D.J. et al.
Partner: UNT Libraries Government Documents Department

Results of a preliminary assessment of an explosive projectile launch system

Description: This report presents results on a preliminary assessment of accelerating a projectile by a sequence of timed explosions. Computerized simulations were performed with CALE, a two-dimensional Arbitrary Language Eulerian program to examine principles and preferred operating parameters.
Date: July 31, 1995
Creator: Reaugh, J. E.
Partner: UNT Libraries Government Documents Department

Reconditioning contaminated gravel

Description: Lawrence Livermore National Laboratory (LLNL) has developed a portable screening system that will recondition radioactively contaminated gravel in the field. The separation technique employed by this system removes dirt, contaminated debris, and other fine particles from gravel. At LLNL, gravel is used in conjunction with the experimental testing of explosives to reduce shock wave propagation. The gravel surrounds the experimental device and buffers the energy generated from the explosion. During an explosion, some of the gravel is broken down into small particles and mixed with contaminants. Contaminants in the used gravel originate from metal sheathing and other parts comprising, the experimental device. These contaminants may consist of radionuclides and metals that are considered hazardous by the State of California when disposed. This paper describes the process that conveys contaminated material into the screener system, sprays the material with recycled water or other mild cleaning chemicals, and separates particles based on size. Particles greater than a specified size are discharged out of the screener separator and recycled back into use, thereby reducing the amount of mixed waste generated and minimizing the need for new gravel. The fines or silt are flushed out of the separator with the water and are removed from the water and consolidated into a drum with the use of a hydrocyclone separator and drum decant system. Because the water in the spray system is recycled, minimal makeup water is needed. The system monitors pH and total dissolved solids.
Date: February 1, 1995
Creator: Walsh, H.; Bowers, J.S. & Cadwell, K.
Partner: UNT Libraries Government Documents Department

An impulse radar array for detecting land mines

Description: The Lawrence Livermore National Laboratory has developed radar and imaging technologies with potential application in demining efforts. A patented wideband (impulse) radar that is very compact, very low cost, and very low power, has been demonstrated in test fields to be able to detect and image nonmetallic land mines buried in 2-10 cm of soil. The scheme takes advantage of the very short radar impulses and the ability to form a large synthetic aperture with many small individual units, to generate high resolution 2-D or 3-D tomographic images of the mine and surrounding ground. Radar range calculations predict that a vehicle-mounted or man-carried system is quite feasible using this technology. This paper presents the results of field tests using a prototype unit and describes practical mine detection system concepts. Predicted capabilities in terms of stand-off range and radiated power requirements are discussed.
Date: April 3, 1995
Creator: Gavel, D.T.; Mast, J.E.; Warhus, J. & Azevedo, S.G.
Partner: UNT Libraries Government Documents Department

Science and Technology Review, June 1997

Description: This report summarizes ongoing research and development projects at Lawrence Livermore National Laboratory. Feature stories this month include explosives, stroke prevention and treatment, and lasers.
Date: June 1, 1997
Creator: Upadhye, R.
Partner: UNT Libraries Government Documents Department

Small-scale cookoff bomb (SSCB) tests on solutions of DMSO/LX-10-1 and DMSO/PBX-9404

Description: The small-scale cookoff bomb test was developed by the Navy at China Lake as a method for evaluation of the violence of thermal decomposition of explosives and propellants. The UN {open_quotes}Recommendations on the Transport of Dangerous Goods - Tests and Criteria{close_quotes} (ST/SG/AC.10/11) have accepted the small-scale cookoff bomb test as a test for classification of a substance as an explosive (class 1 substance) for storage and shipment. The US Departments of Transportation and Defense have agreed to use the UN tests as US criteria for storage and shipment. The UN scheme is designed to assess the relative hazard of explosives so that an appropriate classification for transport can be made by the competent authority (DOT). Three thermal tests have been approved: the Koenen test, the internal ignition test and the small-scale cookoff bomb (SSCB) test. Lawrence Livermore National Laboratory has designed a dissolution work station for removal of the plastic bonded explosives (PBXs) LX-10-1 and PBX-9404 from two artillery fired atomic projectiles (AFAPs) using dimethyl sulfoxide (DMSO) as the solvent. The DOE Explosives Safety Manual allows up to 33% solutions of explosives to be handled as non-explosive in the laboratory and 25% solutions to be stored as non-explosives unless the explosive precipitates out. In order to ship solutions of LX-10-1 or PBX-9404 in DMSO on US highways for waste or recycling as non-explosives, these solutions must be approved for shipping by the DOT based on the results of UN test series 1. The compositions of LX-10-1 and PBX-9404 are given in Table 1. The shock sensitivity of solutions of these two plastic bonded explosives in dimethyl sulfoxide (DMSO) has been evaluated using the UN series 1 gap test for liquids as described in a previous report. The purpose of this paper is to present the results of the SSCB tests ...
Date: September 28, 1994
Creator: Helm, F. & Hoffman, D.M.
Partner: UNT Libraries Government Documents Department

Shock initiation of 1,3,3-trinitroazetidine (TNAZ)

Description: The shock sensitivity of the pressed solid explosive 1,3,3-trinitroazetidine (TNAZ) was determined using the embedded manganin pressure gauge technique. At an initial pressure of 1.3 GPa, pressure buildup (exothermic reaction) was observed after ten {mu}s. At 2 GPa, TNAZ reacted rapidly and transitioned to detonation in approximately 13 mm. At 3.6 GPa, detonation occurred in less than 6 mm of shock propagation. Thus, pure TNAZ is more shock sensitive than HMX-based explosives but less shock sensitive than PETN-based explosives. The shocked TNAZ exhibited little reaction directly behind the shock front, followed by an extremely rapid reaction. This reaction caused both a detonation wave and a retonation wave in the partially decomposed TNAZ. An Ignition and Growth reactive model for TNAZ was developed to help understand this complex initiation phenomenon.
Date: July 19, 1995
Creator: Simpson, R.L.; Urtiew, P.A. & Tarver, C.M.
Partner: UNT Libraries Government Documents Department

Factors affecting the erosion of jets penetrating high explosive

Description: It has been observed in various experiments with shaped charge jets penetrating high explosives that the erosion of the jet can be considerably greater than that expected from analytical theory or from two dimensional hydrodynamic computer simulations. In a previous study, we found that the initial penetration of the jet agreed with theory, and that the erosion of the jet happened subsequent to the initial penetration. This additional erosion can be the dominant factor in the total length of jet that is eroded. We also found that in one experiment the jet did not show any excess erosion and that the penetration could be predicted from theory. We also found a rough correlation of the amount of excess erosion with the diameter of the jet, with larger jet diameters giving less erosion. A problem with previous experiments was that a wide variety of shaped charges, target shapes, and target thicknesses were used. This made it difficult to isolate the effect of a particular parameter. For the current study we chose to isolate the effects of scale and target thickness. For this purpose we used well characterized jets and carefully chosen targets. We also did computer calculations to help elucidate the underlying mechanisms of the excess erosion.
Date: May 1, 1995
Creator: Haselman, L.C. & Winer, K.A.
Partner: UNT Libraries Government Documents Department

LLNL electro-optical mine detection program

Description: Under funding from the Advanced Research Projects Agency (ARPA) and the US Marine Corps (USMC), Lawrence Livermore National Laboratory (LLNL) has directed a program aimed at improving detection capabilities against buried mines and munitions. The program has provided a national test facility for buried mines in arid environments, compiled and distributed an extensive data base of infrared (IR), ground penetrating radar (GPR), and other measurements made at that site, served as a host for other organizations wishing to make measurements, made considerable progress in the use of ground penetrating radar for mine detection, and worked on the difficult problem of sensor fusion as applied to buried mine detection. While the majority of our effort has been concentrated on the buried mine problem, LLNL has worked with the U.S.M.C. on surface mine problems as well, providing data and analysis to support the COBRA (Coastal Battlefield Reconnaissance and Analysis) program. The original aim of the experimental aspect of the program was the utilization of multiband infrared approaches for the detection of buried mines. Later the work was extended to a multisensor investigation, including sensors other than infrared imagers. After an early series of measurements, it was determined that further progress would require a larger test facility in a natural environment, so the Buried Object Test Facility (BOTF) was constructed at the Nevada Test Site. After extensive testing, with sensors spanning the electromagnetic spectrum from the near ultraviolet to radio frequencies, possible paths for improvement were: improved spatial resolution providing better ground texture discrimination; analysis which involves more complicated spatial queueing and filtering; additional IR bands using imaging spectroscopy; the use of additional sensors other than IR and the use of data fusion techniques with multi-sensor data; and utilizing time dependent observables like temperature.
Date: September 30, 1994
Creator: Anderson, C.; Aimonetti, W.; Barth, M.; Buhl, M.; Bull, N.; Carter, M. et al.
Partner: UNT Libraries Government Documents Department

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

Description: As part of the Strategic Environmental Research and Development Program (SERDP) a clean, agile manufacturing of explosives, propellants and pyrotechniques (CANPEP) effort set about to identify new approaches to materials and processes for producing propellants, explosives and pyrotechniques (PEP). The RDX based explosive PBXN-109 and gun propellant M-43 were identified as candidates for which waste minimization and recycling modifications might be implemented in a short time frame. The binders, additives and plasticizers subgroup identified cast non-curable thermoplastic elastomer (TPE) formulations as possible replacement candidates for these formulations. Paste extrudable explosives were also suggested as viable alternatives to PBXN-109. Commercial inert and energetic TPEs are reviewed. Biodegradable and hydrolyzable binders are discussed. The applicability of various types of explosive formulations are reviewed and some issues associated with implementation of recyclable formulations are identified. It is clear that some processing and weaponization modifications will need to be made if any of these approaches are to be implemented. The major advantages of formulations suggested here over PBXN-109 and M-43 is their reuse/recyclability. Formulations using TPE or Paste could by recovered from a generic bomb or propellant and reused if they met specification or easily reprocessed and sold to the mining industry.
Date: December 1, 1994
Creator: Hoffman, D.M.; Hawkins, T.W. & Lindsay, G.A.
Partner: UNT Libraries Government Documents Department

Landmine policy in the near-term: a framework for technology analysis and action

Description: Any effective solution to the problem of leftover landmines and other post-conflict unexploded ordnance (UXO) must take into account the real capabilities of demining technologies and the availability of sufficient resources to carry out demining operations. Economic and operational factors must be included in analyses of humanitarian demining. These factors will provide a framework for using currently available resources and technologies to complete this task in a time frame that is both practical and useful. Since it is likely that reliable advanced technologies for demining are still several years away, this construct applies to the intervening period. It may also provide a framework for utilizing advanced technologies as they become available. This study is an economic system model for demining operations carried out by the developed nations that clarifies the role and impact of technology on the economic performance and viability of these operations. It also provides a quantitative guide to assess the performance penalties arising from gaps in current technology, as well as the potential advantages and desirable features of new technologies that will significantly affect the international community`s ability to address this problem. Implications for current and near-term landmine and landmine technology policies are drawn.
Date: August 1, 1997
Creator: Eimerl, D., LLNL
Partner: UNT Libraries Government Documents Department

Program for certification of waste from contained firing facility: Establishment of waste as non-reactive and discussion of potential waste generation problems

Description: Debris from explosives testing in a shot tank that contains 4 weight percent or less of explosive is shown to be non-reactive under the specified testing protocol in the Code of Federal Regulations. This debris can then be regarded as a non-hazardous waste on the basis of reactivity, when collected and packaged in a specified manner. If it is contaminated with radioactive components (e.g. depleted uranium), it can therefore be disposed of as radioactive waste or mixed waste, as appropriate (note that debris may contain other materials that render it hazardous, such as beryllium). We also discuss potential waste generation issues in contained firing operations that are applicable to the planned new Contained Firing Facility (CFF). The goal of this program is to develop and document conditions under which shot debris from the planned Contained Firing Facility (CFF) can be handled, shipped, and accepted for waste disposal as non-reactive radioactive or mixed waste. This report fulfills the following requirements as established at the outset of the program: 1. Establish through testing the maximum level of explosive that can be in a waste and still have it certified as non-reactive. 2. Develop the procedure to confirm the acceptability of radioactive-contaminated debris as non-reactive waste at radioactive waste disposal sites. 3. Outline potential disposal protocols for different CFF scenarios (e.g. misfires with scattered explosive).
Date: September 30, 1997
Creator: Green, L., Garza, R., Maienschein, J., Pruneda, C.
Partner: UNT Libraries Government Documents Department