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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.
1

Knowledge-based systems for the demolition industry

Fox, Dominic St John January 1994 (has links)
No description available.
2

Dynamics of small to intermediate volume pyroclastic flows

Calder, Eliza Shona January 1999 (has links)
No description available.
3

A case study of explosive cyclogenesis in the eastern Pacific Ocean 14-17 December 1987.

Curtis, Jan. January 1989 (has links)
Approved for Public release; distribution is unlimited / An explosive cyclogenesis event that occurred in the eastern Pacific Ocean on 14-17 December 1987 is investigated using the National Meteorological Center (NMC) final analyses and Geostationary Operational Environmental Satellite (GOES) digital imagery. Forecasts for this cyclone by the Navy Operational Global Atmospheric Prediction System (NOGAPS 3.0) and NMC Nested Grid Mesh (NGM) forecasts initialized at 12 UTC 14 December are also evaluated. Quasi-Lagrangian budgets of mass and vorticity are computed to determine the factors responsible for the development of this intense cyclone. The initial surface development occurs within a strong baroclinic zone southeast of a significant short-wave trough aloft. Rapid intensification is accompanied by large cyclonic vorticity advection in the upper troposphere as the surface cyclone moves under the divergent quadrant of a 250mb jet streak. A key element in this development is the superposition between the pre-existing surface low and upper level short-wave trough in a favorable weak static stability environment. These observations support earlier studies that upper level forcing acts as a critical catalyst in initiating eastern ocean explosive development. / http://archive.org/details/casestudyofexplo00curt / Lieutenant Commander, United States Navy
4

The viscosity of dacitic liquids measured at conditions relevant to explosive arc volcanism determing the influence of temperature, silicate composition, and dissolved volatile content /

Hellwig, Bridget M. January 2006 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (February 7, 2007) Includes bibliographical references.
5

Pathological examination of fish exposed to explosive based instantaneous pressure change

Godard, Danielle R 23 August 2010 (has links)
Oil and gas exploration in Northern Canada uses explosive-based seismic techniques to locate hydrocarbon reserves beneath waterbodies not frozen to the bottom. The use of explosives in, or near, waterbodies has the potential to harm fishes, primarily through instantaneous pressure changes (IPCs) generated from the detonations. These IPCs can damage soft tissues through the rapid compression and expansion of the swimbladder as the pressure wave passes. In Canada, a document entitled Guidelines for the Use of Explosives In or Near Canadian Fisheries Waters recommends that peak pressures not exceed 100 kPa for the protection of fish, however damage has been reported below this level. To simulate seismic exploration and examine potential pathological changes surrounding the current Guideline, fish across different developmental stages and with varying degrees of swimbladder presence were exposed to a variety of explosive based IPC levels in field experiments. Early life stages of rainbow trout (Oncorhynchus mykiss) including eyed eggs, sac fry, and juveniles were caged and exposed to discrete detonations from 0 to 280 kPa in the Mackenzie Delta, NWT. These fish were subsequently examined for both gross pathological and histological changes to cranial structures as well as swimbladder, kidney, liver and gill tissue. Results showed changes in both the area and circumference of the cranial region of eyed eggs, as well as swimbladder, ocular and kidney damage in juveniles. Additionally, caged adult swimbladder bearing lake trout (Salvelinus namaycush) and non-swimbladder bearing slimy sculpin (Cottus cognatus) were exposed to explosive based IPCs ranging in peak pressure from 0 to 127 kPa at the Experimental Lakes Area, Ontario. Fish were later examined grossly and blood, liver, kidney, intestine, and spleen were examined to determine the presence of any traumatic based pathological changes. Results indicated the occurrence of swimbladder hemorrhage in lake trout exposed to IPCs near the current Guideline level. Finally, a risk assessment for lake trout of the Mackenzie Delta exposed to IPCs was undertaken; to examine the potential for adverse risk to individuals and populations, and the likelihood of populations being unable to recover. Based on the findings of the aforementioned studies, the recommended Guideline level is not protective of early life stages of rainbow trout and furthermore represents the threshold at which damage to the swimbladder in adult lake trout does not occur, as such, a re-examination of the recommended Guideline level is warranted.
6

Pathological examination of fish exposed to explosive based instantaneous pressure change

Godard, Danielle R 23 August 2010 (has links)
Oil and gas exploration in Northern Canada uses explosive-based seismic techniques to locate hydrocarbon reserves beneath waterbodies not frozen to the bottom. The use of explosives in, or near, waterbodies has the potential to harm fishes, primarily through instantaneous pressure changes (IPCs) generated from the detonations. These IPCs can damage soft tissues through the rapid compression and expansion of the swimbladder as the pressure wave passes. In Canada, a document entitled Guidelines for the Use of Explosives In or Near Canadian Fisheries Waters recommends that peak pressures not exceed 100 kPa for the protection of fish, however damage has been reported below this level. To simulate seismic exploration and examine potential pathological changes surrounding the current Guideline, fish across different developmental stages and with varying degrees of swimbladder presence were exposed to a variety of explosive based IPC levels in field experiments. Early life stages of rainbow trout (Oncorhynchus mykiss) including eyed eggs, sac fry, and juveniles were caged and exposed to discrete detonations from 0 to 280 kPa in the Mackenzie Delta, NWT. These fish were subsequently examined for both gross pathological and histological changes to cranial structures as well as swimbladder, kidney, liver and gill tissue. Results showed changes in both the area and circumference of the cranial region of eyed eggs, as well as swimbladder, ocular and kidney damage in juveniles. Additionally, caged adult swimbladder bearing lake trout (Salvelinus namaycush) and non-swimbladder bearing slimy sculpin (Cottus cognatus) were exposed to explosive based IPCs ranging in peak pressure from 0 to 127 kPa at the Experimental Lakes Area, Ontario. Fish were later examined grossly and blood, liver, kidney, intestine, and spleen were examined to determine the presence of any traumatic based pathological changes. Results indicated the occurrence of swimbladder hemorrhage in lake trout exposed to IPCs near the current Guideline level. Finally, a risk assessment for lake trout of the Mackenzie Delta exposed to IPCs was undertaken; to examine the potential for adverse risk to individuals and populations, and the likelihood of populations being unable to recover. Based on the findings of the aforementioned studies, the recommended Guideline level is not protective of early life stages of rainbow trout and furthermore represents the threshold at which damage to the swimbladder in adult lake trout does not occur, as such, a re-examination of the recommended Guideline level is warranted.
7

The explosive compaction of metallic powders

Baird, K. S. January 1987 (has links)
No description available.
8

The mechanics of high velocity oblique impact between a projectile and an anvil

McKee, Fredric Albert January 1975 (has links)
No description available.
9

Laser driven micro-explosive bonding

Alexander, Dale. January 1986 (has links)
Thesis (M.S.)--University of Michigan, 1986.
10

Synthetic and mechanistic studies in polynitroaromatic chemistry

Gibbons, Leslie R. January 1988 (has links)
This project developed from an industrial need for a plasticiser for explosives formulations which is easier to manufacture, more stable than those presently employed, but still based on a polynitroaromatic nucleus. The major aim of this programme was to produce new liquid or low melting polynitroaromatic compounds by simple routes. A literature search highlighted various molecular features which appeared to produce a low melting temperature in polynitroaromatic compounds. Using these features, four categories of compounds were identified as target compounds for a synthetic programme to produce low melting polynitroaromatic compounds. (A: Alkyltrinitrobenzenes; B: trinitrophenylpropanoate esters; C: 3-alkylpicrylethers; D: 3-alkyltrinitrobenzoate esters). 2,4,6-Trinitrotoluene (the preferred starting material for category A and B compounds) forms an anion in basic solution, which has been suggested as having nucleophilic characteristics 3. In fact, this work has shown that it displays very poor nucleophilic qualities, though reaction with p-nitrobenzyl bromide was successful. An ultraviolet and nmr spectroscopic study of this reaction provided evidence to suggest that O'-adduct formation facilitates an ionic substitution reaction; whereas in other cases such O-complex formation is not favoured and radical decomposition of TNT occurs. Three 3-alkylpicryl chlorides have been prepared from 3-alkylphenols as precursors for category C and D compounds. Attempts to prepare such compounds from TNT were unsuccessful. Partial reduction of TNT, to 2,4-diamino-6-nitrotoluene was achieved, but bromination of this compound proved to be uncontrollable, with 2,4-diamino-3,5-dibromo-6-nitrotoluene being the only product. The mechanism of this reaction is discussed. The preparation of 3-alkylpicryl ethers (category C compounds) was successfully achieved and numerous liquids or low melting solids were produced. 3-t-Butylpicryl chloride in reaction with certain alkoxides, displayed a competition between nitro group and halogen substitution, with up to 30% nitro group substitution being observed; a novel reaction in systems of this type. A series of low melting compounds have been prepared from 3-alkylpicryl halides using various sulphur and nitrogen nucleophiles.

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