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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Design, synthesis and characterization of conjugated polymers for the detection of explosives /

Nguyen, Huy H., January 1900 (has links)
Thesis (M.Sc.) - Carleton University, 2008. / Includes bibliographical references (p. 76). Also available in electronic format on the Internet.
82

Physics-based radiometric signature modeling and detection algorithms of land mines using electro-optical sensors

Liao, Wen-Jiao, January 2003 (has links)
Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xxii, 255 p. : ill. (some col.). Advisors: Joel T. Johnson and Brian A. Baertlein, Dept. of Electrical Engineering. Includes bibliographical references (p. 247-255).
83

Analysis of 2-axis pencil beam sonar microbathymetric measurements of mine burial at the Martha's Vineyard Coastal Observatory /

Gotowka, Brendan Reed. January 1900 (has links)
Thesis (M.S.)--Joint Program in Oceanography/ Applied Ocean Science and Engineering, Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution, 2005. / Bibliography: p.96-98.
84

Don't forget about dedicated sea mine countermeasures enhancing operational art and design in the 21st century /

Potts, Malcolm H. January 2005 (has links) (PDF)
Thesis (M.S. in Joint Campaign Planning and Strategy)--Joint Forces Staff College, Joint Advanced Warfighting School, 2005. / "13 May 05." Electronic version of original print document. Includes bibliographical references (p. 73-79).
85

A critical vulnerability, a valid threat U.S. ports and terrorist mining /

Sparks, Michael C. January 2005 (has links) (PDF)
Thesis (M.S. in Joint Campaign Planning and Strategy)--Joint Forces Staff College, Joint Advanced Warfighting School, 2005. / "13 April 2005." Electronic version of original print document. Includes bibliographical references (p. 64-67).
86

A study of the behaviour of emulsion explosives

Allum, J. January 2009 (has links)
This study investigated the formulation and characterisation of emulsion explosives. This included the manufacture of more than 120kg of emulsion explosive of which around 105kg was used on the explosive ordnance range in over 350 individual firings. For each emulsion composition, an average of eight firings was undertaken with which to substantiate the explosive performance data. The formulation was varied to determine the effects of water content upon the physical characteristics of the emulsion. These physical effects included thermal conductivity, particle size, viscosity and the explosive performance of the emulsion. In respect of explosive performance, microballoons were added to sensitise the emulsion and the proportions of microballoons added were altered to look at their effect on velocity of detonation, sensitivity and the brisance of the emulsions. Emulsion explosives are commonly referred, in literature, as Type 11 non-ideal explosives. This is due to their non-linear behaviour with respect to the variation of velocity of detonation with density. Traditionally, when an emulsion explosive was commercially manufactured, the water content has been kept at a minimum (12-17%). This was accepted as the way to achieve the best explosive performance, based upon the belief that an emulsion with the highest concentration of active ingredients, ammonium nitrate and oil, would give the best explosive performance. This study examined a wider range of emulsion explosive water contents than has been previously studied, from 12% to 35% water. It was found, during this study, that higher water content emulsions, specifically 25% water, had a marked increase in explosive performance. The highest velocity of detonation recorded was in a 39mm diameter tube, at 25% water content with 3% microballoons, was 5558ms-1. This was some 15% higher than any other VOD recorded in this study. The high velocity of detonation, at 25% water content, was one of a number of physical characteristics in which this water content varied from the other emulsion water contents. This study endeavored to show that emulsion explosives could exhibit two differing types of explosive reaction, thermal explosion and grain burning. This was based on the velocity of detonation and plate dent data, both of which indicated that there was a change in reaction with water content. Emulsion explosives, with a high water and high microballoon content, exhibited a thermal explosion type reaction. They exhibited Type I ideal explosive behaviour, with increasing velocity of detonation with density. Lower water content emulsion explosives, displayed the more commonly expected Type 11 non-ideal behaviour and reacted in a grain burning type detonation.
87

A Study of the behaviour of emulsion explosives / Department of Environmental and Ordnance Systems

Allum, J 17 November 2009 (has links)
This study investigated the formulation and characterisation of emulsion explosives. This included the manufacture of more than 120kg of emulsion explosive of which around 105kg was used on the explosive ordnance range in over 350 individual firings. For each emulsion composition, an average of eight firings was undertaken with which to substantiate the explosive performance data. The formulation was varied to determine the effects of water content upon the physical characteristics of the emulsion. These physical effects included thermal conductivity, particle size, viscosity and the explosive performance of the emulsion. In respect of explosive performance, microballoons were added to sensitise the emulsion and the proportions of microballoons added were altered to look at their effect on velocity of detonation, sensitivity and the brisance of the emulsions. Emulsion explosives are commonly referred, in literature, as Type 11 non-ideal explosives. This is due to their non-linear behaviour with respect to the variation of velocity of detonation with density. Traditionally, when an emulsion explosive was commercially manufactured, the water content has been kept at a minimum (12-17%). This was accepted as the way to achieve the best explosive performance, based upon the belief that an emulsion with the highest concentration of active ingredients, ammonium nitrate and oil, would give the best explosive performance. This study examined a wider range of emulsion explosive water contents than has been previously studied, from 12% to 35% water. It was found, during this study, that higher water content emulsions, specifically 25% water, had a marked increase in explosive performance. The highest velocity of detonation recorded was in a 39mm diameter tube, at 25% water content with 3% microballoons, was 5558ms-1. This was some 15% higher than any other VOD recorded in this study. The high velocity of detonation, at 25% water content, was one of a number of physical characteristics in which this water content varied from the other emulsion water contents. This study endeavored to show that emulsion explosives could exhibit two differing types of explosive reaction, thermal explosion and grain burning. This was based on the velocity of detonation and plate dent data, both of which indicated that there was a change in reaction with water content. Emulsion explosives, with a high water and high microballoon content, exhibited a thermal explosion type reaction. They exhibited Type I ideal explosive behaviour, with increasing velocity of detonation with density. Lower water content emulsion explosives, displayed the more commonly expected Type 11 non-ideal behaviour and reacted in a grain burning type detonation.
88

Design and implementation of gas chromatography-mass spectrometry (GC-MS) methodologies for the analysis of thermally labile drugs and explosives

Ash, Jordan R. 18 November 2016 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Gas Chromatography/Mass Spectrometry (GC/MS) is an analytical technique that sees frequent use in labs across the world. It is also one of the most common instruments found in forensic science laboratories. This technique can efficiently and accurately separate and identify a broad range of compounds that may be present in evidence submitted for analysis. In this work, the versatility of this instrument was applied to new methodologies for the detection of explosives and illicit drugs. The analysis of explosives by GC/MS is common but can be problematic. The thermally sensitive nature of some explosives can cause them to degrade when introduced to the high temperatures of a GC/MS inlet. This project looked at the design and implementation of a way to separate and detect a variety of nitrate ester explosives in a short amount of time. In addition to this, a new technique known as Total Vaporization-Solid Phase Microextraction (TV-SPME) was utilized as a pre concentration technique. The parameters for TV-SPME were statistically optimized for a low level of detection. The combination of these areas allowed for the separation of ethylene glycol dinitrate, nitroglycerin, erythritol tetranitrate, and pentaerythritol tetranitrate with a detection limit as low as 50 parts per trillion (ppt). Degradation products such as 1-mononitroglycerin, 1-3-dinitroglycerin, and 2-mononitroglycerin were also successfully identified. The problem of thermally labile compounds extends to the world of illicit drugs. In the second project, several derivatization schemes were developed for common controlled substances. N,O-Bis(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane (TMCS) was used for silylation, trifluoroacetic anhydride (TFAA) was sued for acylation, and (N,N-Dimethylformamide dimethyl acetal (DMF-DMA) for alkylation. Three different compound classes totaling 15 different drugs were investigated. N,N-Dimethylformamide dimethyl acetal (DMF-DMA) is presented as a novel way of derivatizing several drugs of interest. Primary amines and zwitterions were derivatized with this reagent to much success, specifically: amphetamine, 2-(4-Iodo-2,5-dimethoxyphenyl)ethan-1-amine (2C-I), pregabalin, and gabapentin.
89

Evaluation of the Odor Compounds Sensed by Explosive-Detecting Canines

Lotspeich, Erica H. 09 March 2011 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Trained canines are commonly used as biological detectors for explosives; however, there are some areas of uncertainty that have led to difficulties in canine training and testing. Even though a standardized container for determining the accuracy of explosives-detecting canines has already been developed, the factors that govern the amount of explosive vapor that is present in the system are often uncertain. This has led to difficulties in comparing the sensitivity of canines to one another as well as to analytical instrumentation, despite the fact that this container has a defined headspace and degree of confinement of the explosive. For example, it is a common misconception that the amount of explosive itself is the chief contributor to the amount of odor available to a canine. In fact, odor availability depends not only on the amount of explosive material, but also the explosive vapor pressure, the rate with which the explosive vapor is transported from its source and the degree to which the explosive is confined. In order to better understand odor availability, headspace GC/MS and mass loss experiments were conducted and the results were compared to the Ideal Gas Law and Fick’s Laws of Diffusion. Overall, these findings provide increased awareness about availability of explosive odors and the factors that affect their generation; thus, improving the training of canines. Another area of uncertainty deals with the complexity of the odor generated by the explosive, as the headspace may consist of multiple chemical compounds due to the extent of explosive degradation into more (or less) volatile substances, solvents, and plasticizers. Headspace (HS) and solid phase microextraction (SPME) coupled with gas chromatography/mass spectrometry (GC/MS) were used to determine what chemical compounds are contained within the headspace of an explosive as well as NESTT (Non-Hazardous Explosive for Security Training and Testing) products. This analysis concluded that degradation products, plasticizers, and taggants are more common than their parent explosive.
90

Microwave Interferometry Diagnostic Applications for Measurements of Explosives

Kline, Loren A 01 July 2017 (has links) (PDF)
Microwave interferometry (MI) is a Doppler based diagnostic tool used to measure the detonation velocity of explosives, which has applications to explosive safety. The geometry used in existing MI experiments is cylindrical explosives pellets layered in a cylindrical case. It is of interest to Lawrence Livermore National Labs to measure additional geometries that may be overmoded, meaning that the geometries propagate higher-order transverse electromagnetic waves. The goal of my project is to measure and analyze the input reflection from a novel structure and to find a good frequency to use in an experiment using this structure. Two methods of determining a good frequency are applied to the phase of the input reflection. The first method is R2, used to measure the linearity of input reflection phase. The second is a zero-crossing method that measures how periodic the input reflection phase is. Frequencies with R2 values higher than .995 may be usable for an experiment in the novel structure.

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