Thesis (Ph.D.) - University of Queensland, 2004. / Includes bibliography.

Inaug.-diss.--Heidelberg. / Lebenslauf. "Litteratur-verzeichnis": p. [131].

Thesis (Ph. D.)--University of Rhode Island, 2006. / Includes bibliographical references (leaves 280-284).

Thesis (DTech (Chemical Engineering))--Cape Peninsula University of Technology, 2017. / Explosives are used to achieve certain functions in diverse environments, including mining, civil construction, military operations, and demolition. Irrespective of the application, the basic principle of augmentation of energy applies. Energy in the form of heat and shock is released by an initiator. This energy is taken up by an intermediary charge, which in turn propagates to the main explosive charge. Ultimately the energy released from the main explosive charge performs the functions. Initiating systems make use of this exact principle within their own boundaries of confinement. The rate at which this energy transfer takes place as well as the magnitude of augmentation is to a great extent influenced by parameters such as the type of confinement, chemical composition and density of the explosives, as well as other environmental conditions. Traditionally lead azide has been used as the primary explosive component in an initiating system. Pressure from international environmental agencies has discouraged the use of heavy metals in commercial products. Nano-porous silicon has been used together with an oxidiser to form an explosive mixture. The literature has shown that nano-porous silicon-based explosive formulations are sensitive enough to pick up from the energy released by the pyrotechnic composition. The reaction of such nano-porous silicon explosive compositions changes from a deflagration to a detonation. However, their ability to initiate the base charge of an initiating system has not yet been demonstrated. A nano-porous silicon/nitriminotetrazole-based explosive system was developed and characterised. A relative reactivity concept was developed and successfully used to further characterise the new nano-porous silicon explosive. The lead azide primary explosive replacement has been shown to be sensitive enough to pick up from the heat output generated by the delay composition and strong enough to reliably initiate the base charge explosive. The performance of the base charge explosive is primarily a function of its density and the confinement it is used in. An explosive system was developed whereby the base explosive was coated with a polymer to give it compressible characteristics. A ballistic ball indentation evaluation method was developed and effectively applied to characterise explosive performance behaviour under various conditions, including density and confinement. Explosive pellets, pressed separately and at a higher density, have been shown to increase performance compared with explosives consolidated inside an aluminium casing.

Triacetone triperoxide (TATP), a cyclic peroxide explosive, is frequently used by terrorists and amateur chemists due to the ease of synthesis and the availability of reagents. TATP is extremely sensitive to shock, heat, and friction thus a safe and rapid method for treating TATP is needed. The major objective of this dissertation was to develop in situ methodologies that could safely degrade TATP in various field situations. Initial studies focused on using zero-valent metals and mechanically alloyed metals to decompose TATP samples in both aqueous and organic solutions. The metal systems tested included zero-valent iron, magnesium, and magnesium bimetal, Mg/Pd. The TATP degradation reaction with the different reactive metal systems followed pseudofirst order reaction kinetics with respect to TATP concentration, and the half-lives for TATP degradation with the different reactive metal systems were calculated to test their effectiveness. The major degradation product for the TATP decomposition was determined as acetone, and carbon material balance was calculated to determine each reactive system’s efficiency. The mechanism of TATP degradation using these reactive metal/bimetal particles was also explored, including reaction pathway, intermediates, and activation energies. In addition to investigating the use of zero-valent metals to degrade TATP, studies were also conducted on the use of certain metal and semimetal ionic species. Antimony (III) ions were found to have the greatest effect of TATP concentration. Various spectroscopic analyses were completed to try to characterize the reaction iv between the Sb3+ and TATP. The Sb3+ was theorized to instantaneously cleave the ring structure of the TATP molecule forming a Sb3+ complex thus Sb3+systems could be used to successfully treat TATP. In order to treat TATP in the field, the metal and bimetal reactive particles were combined with an application technology, liquid membrane systems to form emulsified zero-valent metal (EZVM) systems. EZVM systems containing the reactive metal/bimetal particles were made from an organic outer layer (corn oil), water, and a nonionic surfactant (SPAN 80). The EZVM systems were observed to absorb and dissolve the TATP into the emulsion droplets where TATP degradation then occurred. EZVM systems would be ideal for degrading dry TATP residues that might be found on a carpet, door entrance, steel, concrete, plastics, etc. The other neat metal systems could also be used to degrade aqueous slurries of TATP on different surfaces if an efficient delivery system was used. Other studies focused on the use of microscale mechanically alloyed bimetals, particularly Mg/Pd, Fe/Pd, and Fe/Ni, as alternative remediation methods for the catalytic reduction of environmental contaminants: 2, 4, 6-trinitrotoluene (TNT), and 1, 3, 5- trimethylene-2, 4, 6-trinitramine (RDX) which have been found to contaminate soil and ground/surface water near industrial production sites. All the bimetals tested were shown to reduce TNT and RDX contamination in water samples with varying reactivities under ambient reaction conditions. These metal systems could be combined with EZVM or paste treatment systems (bimetal treatment systems, BTS) for the in situ treatment of these environmental contaminants.

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / Improvised explosive devices (IEDs) are a global threat due to their destructive potential, the easy access to raw materials, and online instructions to manufacture them. These circumstances have led to an increase in the number of IEDs using potassium chlorate as an oxidizer. The standard methods to detect chlorate are mainly designed for laboratory-only testing. Thus, field instrumentation capable of detecting oxidizers from explosives fuel-oxidizers is critical for crime scene investigation and counterterrorism efforts (described in Chapter 1). We developed a paper-based sensor for the in-field detection of chlorate (described in Chapter 2). The sensor is low-cost, disposable, portable, and inexpensive to fabricate, and its flexibility features allow for surface sampling without sample destruction. The sensor has an electrodeposited molybdate sensing layer, as chlorate was reported to have a catalytic effect on the molybdate reduction. The chlorate detection relies on monitoring the change in redox activity of the molybdate sensing layer using different electroanalytical techniques. We effectively demonstrated the analytical performance of the sensor (Chapter 3), obtaining a limit of detection of 1.2 mM and a limit of quantification of 4.10 mM. We evaluated the selectivity of the sensor by testing other oxidizers, such as perchlorate and nitrate, which did not present any electrochemical activity with the molybdate sensing layer. Additionally, we performed an interferent study with sugar, commonly used as fuel in IEDs, and other common white household powders such as baking soda, flour, and corn starch and neither a false positive nor a false negative result was observed (Chapter 3). As bromate has been reported to have a stronger catalytic effect than chlorate on the redox activity of molybdate, the quantification of bromate was also explored, and a bromate sensor was developed using the findings of the chlorate sensor (Chapter 4). The reaction mechanism involved in the molybdate reduction was explored and discussed in Chapter 5. The capability of the sensor in detecting chlorate from combusted samples and post-blast samples was successfully demonstrated in Chapter 6, as well as the design of encased prototypes to allow for an in-field presumptive test, storage, and transport for in-laboratory confirmatory tests and compared the performance of the sensor to the available commercial tests.

The development of a versatile system capable of providing rapid, portable, and inexpensive detection of explosives and energetic compounds is needed critically to offer an enhanced level of protection against current and future threats to homeland security, as well as to satisfy a wide range of applications in the fields of forensic analysis, emergency response, and industrial hazards analysis. The hand-held nanocalorimeter will serve as a first-of-its-kind screening tools for explosive and energetic compounds directly in the settings where they are needed with high efficiency, reduced cost, and simplicity with ease of use. Unlike current explosives detectors, this system is based on calorimetric techniques that are inherently capable of providing direct measurements of energy release potential and therefore do not depend on prior knowledge of familiar compounds. The microfabricated calorimetry instrument consists of (i) a thermal control module incorporating arrays of microfabricated heaters and temperature sensors, as well as any necessary electronic interconnections, and (ii) a sample encapsulation module incorporating etched enclosures designed to accommodate either solid or liquid samples. Initial work has led to successful fabrication of a chip capable of sampling nano-sized solid or liquid compounds. Control algorithms incorporating the DSC principle have also been written using LabVIEW. Device performance of the original and redesigned chips were tested by studying the thermal transitions associated with the boiling points of acetone and pentane. With the redesigned chip, the heat loss issue was reduced: the measured input heat was reduced from 32 times of the required energy to 5 times of the required energy. Future work will focus on modifying the chip design and control algorithm to improve accuracy and sensitivity, developing a trace analysis software to link it to a database of explosive information, and adapting different fabrication procedures for high temperature operation and large scale production.

Thesis (M.S.)--Naval Postgraduate School, 2002. / Thesis advisor(s): Alan R. Washburn, Samuel E. Buttrey. Includes bibliographical references (p. 39). Also available online.

Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, June 2004. / Thesis advisor(s): Peter C. Chu. Includes bibliographical references (p. 45). Also available online.