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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.
41

Development, Characterization and Application of a Reactive Bulking Agent for Wall Control

Silva, Guillermo C.O. 13 November 2007 (has links)
This research thesis is focussed on the development of a novel low density explosive composition whose main application is wall control in open pit mining. The product has, however, the potential to be used in a variety of applications and rock conditions where customization of the explosive’s energy output is required. Experimental observations on the novel low density explosive showed that the product is capable of initiating and sustaining stable detonations at densities as low as 0.10 g/cm3. Given the extreme low densities at which the novel product maintains its detonating characteristics, it will be appropriate to treat it as a reactive bulking agent, hence its name: Low Density Reactive Agent or LDRA for short. When mixed with standard ANFO prills, the reactive nature of the LDRA ensures a detonable mixture regardless of the final dilution sought or the degree of segregation eventually produced during mixing and loading. If operational constraints are such that a lower energy is required, the LDRA can then be used on a stand‐alone basis, without mixing it with other explosive compositions, such as ANFO or emulsions. The detonation characteristics of the LDRA at a target density of 0.15 g/cm3 were evaluated, with particular effort placed on measuring the detonation and explosion pressures, parameters having the greatest influence on damage. The effects of diameter, confinement and primer on LDRA performance were evaluated through velocity of detonation (VOD) measurements. In addition, VOD experiments were conducted in the LDRA to evaluate the stability of propagation in longer columns, the behaviour in a decking configuration and the ability to initiate and be initiated by a column of ANFO. The low pressure regimes characterizing the LDRA provided the opportunity to investigate the full pressure history of the detonation gases by designing experiments of a non‐destructive nature that allowed the repetition of tests under different loading scenarios. Following the characterization stage, the opportunity to test the LDRA as a damage control tool under a true operational scenario arose at the Chuquicamata Mine, in northern Chile. The project provided important input as to the feasibility of manufacturing the LDRA at a semi‐industrial scale and to evaluate the performance of the product in the large diameter blastholes used at the mine / Thesis (Ph.D, Mining Engineering) -- Queen's University, 2007-11-09 12:19:49.747
42

Continuous wave terahertz frequency spectroscopy and imaging for explosives detection and security screenings

Startsev, Michael Andrei Unknown Date
No description available.
43

An investigation of propellant stabiliser degradation products

Elliot, Mark January 1995 (has links)
Chemical stabilisers are incorporated into nitrate ester based propellant formulations to react with the initial propellant decomposition products, preventing the onset of autocatalytic deterioration of these energetic constituents. As a result of these interactions the stabiliser forms a number of derivatives. Sources of these propellant stabiliser degradation products are vital for investigating the course of propellant breakdown and for the validation of several established stability tests. Synthetic methodologies have been developed which yield targeted derivatives of diphenylamine via catalysed and uncatalysed nucleophilic aromatic substitutions in conjunction with standard nitrosating techniques. Ethylcentralite, used in double or triple base propellants, reacts depending on stabiliser concentration, to give two distinct groups of degradation products. Those based on the N-ethylaniline nucleus and those based on the parent stabiliser. The derivatives based on N-ethylaniline have been synthesised utilising a variety of synthetic approaches including phase transfer catalysed N-alkylation, while the utility of urea synthesis employing the reaction between anilines and isocyanates has been evaluated as a possible route towards the second group of ethylcentralite propellant stabiliser degradation products. High performance liquid chromatographic techniques have been developed for the quantitative assay of the diphenylamine and ethylcentralite stabiliser derivatives synthesised. Preliminary analysis of different single base propellants, stabilised by diphenylamine, indicate markedly different degrative product profiles for each of the samples studiedFinally an investigation of a resorcinol stabilised model propellant system has provided evidence that 2-nitroresorcinol, 4-nitroresorcinol and lacmosol are propellant stabiliser degradation products of the aforementioned stabiliser
44

Discrimination between earthquakes and chemical explosions in Eastern Russia using amplitude ratios obtained from analog records

Linkimer, Lepolt. January 2006 (has links)
Thesis (M. S.)--Michigan State University. Dept. of Geological Sciences, 2006. / Title from PDF t.p. (viewed on June 19, 2009) Includes bibliographical references (p. 116-120). Also issued in print.
45

Application of the systems engineering process to the explosive ordnance disposal requirement for an underwater system /

Nusom, F. Allen. January 1990 (has links)
Project report (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Includes bibliographical references (leaves 96-97). Also available via the Internet.
46

Improving situational awareness in the counter-IED fight with the utilization of unmanned sensor systems

Whiteman, Shannon J. January 2009 (has links) (PDF)
Thesis (M.S. in Systems Engineering)--Naval Postgraduate School, June 2009. / Thesis Advisor(s): Paulo, Eugene. "June 2009." Description based on title screen as viewed on July 14, 2009. Author(s) subject terms: improvised explosive device, counter-IED, ,situational awareness, unmanned sensor systems. Includes bibliographical references (p. 93-97). Also available in print.
47

Combustion of reactive metal particles in high-speed flow of detonation products

Tanguay, Vincent, January 1900 (has links)
Thesis (Ph.D.). / Written for the Dept. of Mechanical Engineering. Title from title page of PDF (viewed 2009/06/11). Includes bibliographical references.
48

Experimental investigation of failure markings associated with nitromethane detonation

Mack, David, January 2009 (has links)
Thesis (M.Eng.). / Written for the Dept. of Mechanical Engineering. Title from title page of PDF (viewed 2009/06/17). Includes bibliographical references.
49

The effect of sensor performance on safe minefield transit /

Kim, Chihoon. January 2002 (has links) (PDF)
Thesis (M.S. in Operations Research)--Naval Postgraduate School, December 2002. / Thesis advisor(s): Steven E. Pilnick, Patricia A. Jacobs, Donald P. Gaver. Includes bibliographical references (p. 101). Also available online.
50

A laboratory determination of peak force and energy requirements for the fragmentation of rock under explosive loading

Howell, Robert Clarence, January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1971. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.

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