Doctor of Philosophy / Department of Mechanical and Nuclear Engineering / William L. Dunn / The signature-based radiation scanning (SBRS) technique can be used to rapidly detect nitrogen-rich explosives at standoff distances. This technique uses a template-matching procedure that produces a figure-of-merit (FOM) whose value is used to distinguish between inert and explosive materials. The present study develops a tiered-filter implementation of the signature-based radiation scanning technique, which reduces the number of templates needed. This approach starts by calculating a normalized FOM between signatures from an unknown target and an explosive template through stages or tiers (nitrogen first, then oxygen, then carbon, and finally hydrogen). If the normalized FOM is greater than a specified cut-off value for any of the tiers, the target signatures are considered not to match that specific template and the process is repeated for the next explosive template until all of the relevant templates have been considered. If a target’s signatures match all the tiers of a single template, then the target is assumed to contain an explosive. The tiered filter approach uses eight elements to construct artificial explosive-templates that have the function of representing explosives cluttered with real materials. The feasibility of the artificial template approach to systematically build a library of templates that successfully differentiates explosive targets from inert ones in the presence of clutter and under different geometric configurations was explored. In total, 10 different geometric configurations were simulated and analyzed using the MCNP5 code. For each configuration, 51 different inert materials were used as inert samples and as clutter in front of the explosive cyclonite (RDX). The geometric configurations consisted of different explosive volumes, clutter thicknesses, and distances of the clutter from the neutron source. Additionally, an objective function was developed to optimize the parameters that maximize the sensitivity and specificity of the method.

Approved for public release; distribution is unlimited / The Navy's CASS/GRAB sonar model is used to accurately simulate a side-scan sonar image with a mine-like object present through its reverberation characteristics. The acoustic impact of a suspended sediment layer is investigated numerically using CASS/GRAB through changing the volume scattering characteristics of the lower water column. A range of critical values of volume scattering strength were discovered through repeated model simulations. An understanding of the acoustic characteristics of suspended sediment layers can aid the Navy in the detection of mines that might exist within these layers. / Lieutenant, United States Navy

In fulfilment of the requirements for the Masters of Management by Research degree Wits Graduate School of Business Faculty of Commerce, law and Management University of the Witwatersrand / The pressure on the current mining sector in South Africa has forced South African explosives companies to expand their activities into Sub-Saharan countries in order to sustain and grow their sales and profits. The purpose of the research was to assess the efficiency of the existing strategic frameworks presented by the literature and deployed by the explosives companies expanding operations in Sub-Sahara and to understand if and how they need to be adapted to suit the explosives market. The research was thus guided by the following research questions: How effective are actual strategic frameworks for the development of an African strategy for South African explosives companies willing to expand operations in Africa? Why aspects of current strategic frameworks do not apply to the commercial explosives business in Africa? Why would it be necessary to include other key variables in existing strategic frameworks to develop an effective strategy for the explosives business? How do other non-manageable variables such as politics, legal, cultural and administrative barriers impact on the shaping of the final strategy for South African explosives companies willing to expand their operations into Africa? The research method followed was a single case study research approach leading to the conclusion that, despite developing different strategies by existing explosives suppliers, they performed well and showed growth in sales and profits. Notwithstanding their success, the investigation revealed that some challenges and specific aspects of the explosives market were not addressed by either the explosives companies’ strategies or the main strategic frameworks described in the literature. Furthermore, the analysis identified external factors, such as commodity prices, which contributed more to the success of explosives companies than the strategies they implemented. The results of the analysis described above led to the development of a strategic framework which included the elements of strategies used by explosives companies, relevant model elements from existing strategic frameworks, external factors (rival explanation) such as commodity prices and variables which take into account the challenges encountered by explosives companies in Sub-Saharan Africa as well as specific aspects of the explosives market. It is believed that the strategic framework developed in the last section of the present research takes into account the particular aspects of the explosives market and empowers South African explosives companies with a framework which addresses the specific aspects of the explosives markets to develop successful businesses in Sub-Saharan Africa.

Student Number : 9608998A - MSc dissertation - School of Electrical and Information Engineering - Faculty of Engineering and the Built Environment / The history of flux compression is relatively short. One of the founders, a Russian physicist, Sakharov developed the idea of compressing a magnetic field to generate high magnetic fields and from this he also developed a generator to produce current impulses. Most of this initial work was performed in military research laboratories. The first open source literature became available in the 1960s and from there it has become an international research arena. There are two types of flux compression generators, field generators and current generators. These are discussed along with the basic theory of flux compression generators and related physics. The efficiency of generators is often quite low. However in many generators high explosives are used and because of their high energy density, the current or field strength produced is substantially greater then the initial source. This of course limits the locations possible for experimental work and subsequently limits the industrial applications of flux compression generators . This research presents a theoretical design for a non-explosive flux compression generator. The generator is designed to produce a current impulse for tests in laboratory and remote locations. The generator has the advantage of being non-destructive, therefore reducing costs, and allowing for repeatable experiments. The design also reduces the possibilities or many of the loss mechanisms.

Alguns altos explosivos foram caracterizados por espectroscopia Raman e no Infravermelho, e o efeito da temperatura sobre os espectros Raman foi medido in-situ. Foram estudados os produtos comerciais TNT, HMX, RDX e PETN, os quais, com exceção do HMX e RDX, pertencem a classes químicas distintas e também foi investigado o TATP sintetizado no laboratório. As amostras foram inicialmente caracterizadas por FT-IR, FT-IR/ATR e espectroscopia Raman com excitação no visível (632,8 nm) e no NIR (1064 nm) visando determinar se a técnica de amostragem exercia algum efeito, especificamente transições de fase e degradação, sobre os espectros. ATR e FT-Raman forneceram os espectros a partir dos quais foi feita a atribuição de bandas, a qual foi suportada por simulações teóricas (DFT, B3PW91). Cada amostra foi aquecida até uma temperatura abaixo do ponto de fusão, na qual o comportamento do espectro com o aquecimento era reversível. No caso do PETN e TNT esse valor foi bem próximo do ponto de fusão e no caso do HMX e RDX, foi substancialmente inferior. As bandas mais afetadas pela temperatura devem ser aquelas envolvidas nas rotas de relaxação de energia em explosivos. Os resultados obtidos sugerem que o PETN sofra decomposição térmica através da ruptura da ligação C-ONO2, enquanto que no HMX e RDX a ligação N-N deve ser rompida. As mudanças no espectro do TNT indicam que vibrações envolvendo os grupos NO2 e a ligação C-N são as mais sensíveis à temperatura. TATP sublima à temperatura de 70°C e até essa temperatura o espectro não é afetado pelo calor. Provavelmente a energia é utilizada no processo de sublimação. / Selected high explosives were characterized by Raman and Infrared spectroscopies and the effect of temperature was followed in-situ by Raman spectroscopy. TNT, HMX, RDX, PETN (commercial products) and TATP belong to distinct chemical families (except HMX and RDX) and their response to heating was evaluated. The samples were first characterized by FT-IR, FT-IR/ATR and Raman with excitation in the visible (632.8 nm) and in the NIR (1064 nm) aiming at the detection of sampling effects in the obtained spectra, specifically phase transitions and degradation. ATR and FT-Raman were the techniques of choice to provide the spectra for band assignment, which was assisted by theoretical simulations (DFT). Each sample was heated up to a temperature well below its melting point, in order to avoid thermal decomposition. The bands most affected by temperature were taken as the routes for energy relaxation in explosives. The obtained results lead to the conclusion that PETN decomposes through the rupture of the C-ONO2 bond, whereas in HMX and RDX the N-N bond is broken. TNT spectra indicates that the NO2 and C-N vibrations are the most sensitive to temperature and TATP sublimated at 70°C and no bands were affected by temperature. The results are agreement with the literature or theoretical simulations.

Since September 11, 2001, money and resources have been allocated at unprecedented levels in order to prevent future attacks on the United States. In the interest of preventing a similar type of incident, counterterrorism initiatives were funded using public funds with little or no oversight as to measuring the effectiveness of these programs. The purpose of this quantitative study was to determine if there was a statistically significant difference in the dependent variable - the level of awareness of participants (the ability to identify terrorism threats) who attended counterterrorism training that was solely lecture based and one that combined both lecture and demonstration. Three theoretical frameworks provided the foundation for this study: The organizational knowledge creation theory, adult learning theory and the experiential learning theory. The Solomon four-group design was employed using 412 test subjects who attended the Federal Bureau of Investigation's National Improvised Explosives Familiarization/Chemical Industry Outreach Workshop . The results of a factorial ANOVA revealed no statistically significant difference in posttest scores between the inexpensive lecture and the more expensive lecture and demonstrations methodologies; however, the results from the paired t test with a p < .001 did demonstrate cost-effectiveness with an average increase of 14 points in the level of awareness from pre- to posttest. The positive social change implications stemming from this study include recommendations to identify objective measures for program effectiveness in all government programs in compliance with the Administrative Procedures Act of 1981. If followed such actions would demonstrate good governance and are likely to increase the public's trust.

The energetic compounds TNT (2,4,6-trinitrotoluene), RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), and HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) contaminate military testing ranges worldwide yet are known to be degraded by plants and microbes in the laboratory. However, these contaminants remain persistent in the environment and represent a health threat to both humans and ecosystems. The use of traditional soil remediation technologies, such as landfilling or incineration, require large excavation costs and disrupt the ecology of the site. Phytoremediation, the use of green plants for the in situ treatment of contaminants, may be the most appropriate means of treating energetic residues present at military testing ranges. Eglin Air Force Base (EAFB), located near Niceville, FL, is one of the largest military installations in the world and holds many plant and animal species which are threatened or endangered. The use of explosives during training exercises on firing ranges at EAFB has resulted in contamination of energetics on range soils. In an effort to increase range sustainability with respect to explosives contamination, EAFB has been established as the site where phytoremediation processes will be explored for this research.

Quantum cascade laser (QCL) diodes have potential applications in many areas including emissions analysis and explosives detection, but like many solid-state devices they suer from degraded performance at higher temperatures. To alleviate this drawback, the thermal properties of the QCL diodes must be better understood. Using molecular dynamics (MD) and photothermal radiometry (PTR), the thermal conductivity of a representative QCL diode is computed and measured respectively. The MD results demonstrate that size eects are present in the simulated systems, but if these are accounted for by normalization to experimental results the thermal conductivity of the QCL can be reasonably obtained. The cross-plane conductivity is found to be in the range of 1.8 to 4.3 W=m K, while the in-plane results are in the range of 3.7 to 4.0 W=m K. These values compare well with experimental results from the literature for both QCL materials and for AlInAs and GaInAs, which the QCL is composed of. The cross-plane conductivity results are lower than those of either AlInAs or GaInAs, which demonstrates the phonon scattering at the interfaces. The in-plane results are between AlInAs and GaInAs, which is to be expected. The PTR results are less concrete, as there seem to be heat transfer eects active in the samples which are not included in the models used to t the frequency scans. These effects are not 2D heat transfer artifacts nor are they the result of volumetric absorption. It is possible that they are the results of plasmon induction, but this is only supposition. As the data stand, the PTR and MD results are within an order of magnitude of each other and follow reasonable trends, which suggests that both results are not too far o from reality. While the experimental results are not entirely conclusive, the simulations and experiments corroborate each other suciently to warrant further investigation using these techniques. Additionally, the simulations present sucient internal consistency so as to be useful for thermal property investigation independent of the PTR results.

This thesis is mainly focused on the reactions of oxo-pyrimidines and oxo-imidazoles with nitric acid in sulfuric acid and properties of the gem-dinitro products formed in this process. Low temperature nitrations of 2-methylimidazoles produced – in addition to the known 2-methyl-5(4)-nitroimidazole – 2-(dinitromethylene)-5,5-dinitro-4-imidazolidinone and parabanic acid. This tetranitro compound was also obtained via nitration of 2-methyl-4,4-dihydro-(1H)-5- imidazolone. Thermal decomposition of 2-(dinitromethylene)-5,5-dinitro-4-imidazolidinone yielded 2-(dinitromethylene)-4,5-imidazolidinedione, which also was the product from the nitration of the new compound 2-methoxy-2-methyl-4,5-imidazolidienedione. Treatment of 2- (dinitromethylene)-5,5-dinitro-4-imidazolidinone with aqueous ammonia resulted in the previously unknown 1,1-diamino-2,2-dinitroethylene (Paper I). The nitration of some 2-substituted pyrimidine-4,6-diones in sulfuric acid, which afforded previously unknown 5,5-gem-dinitro-pyrimidine-4,6-diones in high yields, was studied. Alloxane was prepared in a one-step procedure by thermal decomposition of 5,5-dinitrobarbituric acid in hot acetic acid. The gem-dinitro products were found to be easily attacked by nucleophiles with concomitant formation of gem-dinitroacetyl derivatives, which in turn could be further hydrolysed to salts of dinitromethane and triureas (Papers II and III). Nitration of 4,6-dihydroxypyrimidine in sulfuric acid yielded nitroform as the sole product. This behaviour was tentatively explained by the formation of an intermediate, 5,5-dinitro-4,6- dihydroxypyrimidine, which underwent hydrolysis in the nitrating acid into gem-dinitroacetyl formamidine. This compound was further nitrated in the same reaction mixture into trinitroacetylformamidine, which finally underwent hydrolytic cleavage into nitroform. It was also demonstrated that gem-dinitroacetylureas could produce nitroform upon nitration. The structures of the proposed trinitroacetylureas were confirmed by the isolation of one of their derivatives (Paper IV). / QC 20100907

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