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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.
71

Numerical simulation of dynamic spontaneous imbibition with variable inlet saturation and interfacial coupling effects using Bentsen’s transport equation

Yazzan Kountar, Saddam Unknown Date
No description available.
72

Field observations of filter feeding in Mytilus edulis populations in Petpeswick Inlet, Nova Scotia.

Knips, Franziska Kathrin January 1973 (has links)
No description available.
73

The Characterisation and Development of a Passivated Inlet to Selected Ion Flow Tube Mass Spectrometry (SIFT-MS)

Reed, Christine Jane January 2010 (has links)
SIFT-MS is a relatively new trace gas analysis technique that has wide application. One particular attribute of the instrument is the ability to detect and quantify volatile organic compounds to the parts per trillion in real-time without the need for sample preparation. However the issue of maintaining accuracy at these low concentrations required attention as it was evident large or polar analytes were being lost by adsorption to the SIFT instrument’s inlet system. The purpose of this research was to evaluate the performance of a passivated inlet in lowering any adsorption in the inlet system compared to the current unpassivated inlet of the SIFT instrument. Volatile concentrations of vanillin (C₈H₈O₃ 152.15 g/mol), ammonia (NH₃ 17.03 g/mol), and hydrogen sulfide (H₂S 34.08 g/mol) were measured. The results determined the passivated inlet provided a significantly better inlet response to these compounds. Consequently improved passivated inlets were installed on current models of SIFT-MS VOICE200®, and also the research laboratory VOICE100™ instrument. Having established a more reliable sampling system for very low concentrations of analyte, attention was paid to SIFT-MS flavour analysis of two foods, cheese and chocolate. The volatile matrix of these foods is highly complex and the compounds of interest are typically difficult to measure. The key aroma compounds for analysis were based on reported literature and earlier SIFT-MS studies which provided a useful framework for the current food flavour research. A significant finding from the SIFT-MS examination of Parmesan cheese is that differences in the relative concentration of some characteristic aroma compounds were a consequence of the milk type used in manufacture. Endogenous enzymes responsible for a multitude of reactions are mostly if not completely inactivated by the pasteurization temperature. A similar analysis approach was attempted for chocolate analysis. Here flavour differences were not as clearly recognised as for the cheese samples. In chocolate there are a greater number of parameters that are involved in its manufacture. Nevertheless, some recognisable differences in chocolate could be attributed to cocoa bean type and flavour additions by the manufacturer.
74

Hydrodynamics and Morphologic Modelling of Alternative Design Scenarios Using CMS: Shippagan Gully, New Brunswick

Provan, Mitchel 02 December 2013 (has links)
Shippagan Gully is a highly dynamic tidal inlet located on the Gulf of St-Lawrence near Le Goulet, New Brunswick. This tidal inlet is highly unusual due to the fact that the inlet has two open boundaries with phase lagged tidal cycles that drives flow through the inlet. Over the past few decades, the shipping activities through the inlet have been threatened due to the narrowing of the navigation channel caused by deposited sediment on the east side of the channel. Many engineering projects have been undertaken at Shippagan Gully in order to try and mitigate the deposition problem. However, these attempts have either been unsuccessful or the engineered structures have deteriorated over the years. This study uses the CMS-Flow and CMS-Wave numerical models to provide guidance concerning the response of the inlet to various potential interventions aimed at improving navigation safety.
75

The ecotourism potential of the Barber Inlet Wetlands, South Australia /

Higginson, Gareth Edward. January 2000 (has links) (PDF)
Thesis (M.Env.St.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 2000. / Bibliography: leaves 127-134.
76

A study of Barnegat inlet, New Jersey and related shoreline phenomena ...

Lucke, John B. January 1900 (has links)
Thesis (Ph. D.)--Princeton University, 1933. / "Reprinted from Shore and beach, journal of the American shore and beach preservation association, vol. II, no. 2., April, 1934." Bibliography: p. 54.
77

Parametric Analysis of a Hypersonic Inlet using Computational Fluid Dynamics

January 2013 (has links)
abstract: For CFD validation, hypersonic flow fields are simulated and compared with experimental data specifically designed to recreate conditions found by hypersonic vehicles. Simulated flow fields on a cone-ogive with flare at Mach 7.2 are compared with experimental data from NASA Ames Research Center 3.5" hypersonic wind tunnel. A parametric study of turbulence models is presented and concludes that the k-kl-omega transition and SST transition turbulence model have the best correlation. Downstream of the flare's shockwave, good correlation is found for all boundary layer profiles, with some slight discrepancies of the static temperature near the surface. Simulated flow fields on a blunt cone with flare above Mach 10 are compared with experimental data from CUBRC LENS hypervelocity shock tunnel. Lack of vibrational non-equilibrium calculations causes discrepancies in heat flux near the leading edge. Temperature profiles, where non-equilibrium effects are dominant, are compared with the dissociation of molecules to show the effects of dissociation on static temperature. Following the validation studies is a parametric analysis of a hypersonic inlet from Mach 6 to 20. Compressor performance is investigated for numerous cowl leading edge locations up to speeds of Mach 10. The variable cowl study showed positive trends in compressor performance parameters for a range of Mach numbers that arise from maximizing the intake of compressed flow. An interesting phenomenon due to the change in shock wave formation for different Mach numbers developed inside the cowl that had a negative influence on the total pressure recovery. Investigation of the hypersonic inlet at different altitudes is performed to study the effects of Reynolds number, and consequently, turbulent viscous effects on compressor performance. Turbulent boundary layer separation was noted as the cause for a change in compressor performance parameters due to a change in Reynolds number. This effect would not be noticeable if laminar flow was assumed. Mach numbers up to 20 are investigated to study the effects of vibrational and chemical non-equilibrium on compressor performance. A direct impact on the trends on the kinetic energy efficiency and compressor efficiency was found due to dissociation. / Dissertation/Thesis / M.S. Aerospace Engineering 2013
78

The voltammetric determination of copper and lead in seawater : applications to Indian Arm and Burrard Inlet

Erickson, Paul Eric January 1973 (has links)
An anodic stripping voltammetric technique was developed for the simultaneous determination of Cu and Pb in seawater. Mercuric ion added to the sample is plated out with the metals of interest onto a highly polished glassy carbon electrode. The thin mercury films obtained by this procedure gave excellent resolution and sensitivity although a non-linear response resulted in the case of Cu, presumably as a result of saturation of the mercury, at concentrations in excess of 4 μg/1. The technique was applied to a short term study of the distribution of Cu and Pb in Indian Arm and Burrard Inlet. Large fluctuations in the concentrations of both metals were observed during the sampling period, July to October, 1972. Although dissolved Pb concentrations were lower than might be expected near a large urban area, there was, nevertheless, an overall enrichment of the subsurface waters of the inlets relative to Georgia Strait by as much as an order of magnitude. Dissolved Cu concentrations were not, however, significantly higher than those reported for other B.C. coastal waters. Although study of metal speciation by the method employed here was limited by the excess of mercuric ions added to the samples and interferences from surface active agents, evidence was obtained indicating that a portion of Cu in some British Columbia coastal seawater samples is complexed with dissolved organic matter. The experimental conditions indicate that these complexes are either inert to displacement by mercuric ions or have a high degree of specificity for Cu. / Science, Faculty of / Chemistry, Department of / Graduate
79

Some features of the life history of the cockscomb prickleback : Anoplaruchus purpurescens Gill

Peppar, John Lovell January 1965 (has links)
The cockscomb prickleback, Anoplarchus purpurescens Gill, family Stichaeidae, ranges from Attu Island and Pribilof Islands, Alaska, to central California. In British Columbia coastal waters it is a bottom-dwelling intertidal species, geographically sympatric with A. insignis, which appears to prefer deeper water than A. purpurescens. A. purpurescens was collected and studied at an intertidal site at Second Narrows, Burrard Inlet, Vancouver, British Columbia. Morphological variation within the population studied, was examined by both measurements and meristic counts. Data obtained were used to differentiate the population of A. purpurescens used in the study, from its sibling species A. insignis. Food and feeding habits were studied over a wide range in size, with emphasis on habitat and seasonal differences shown. Relative importances of various food items reflected differences in availability of organisms utilized as food at various tide levels. Food intake is curtailed in adult fish approaching and during the breeding season. Marking experiments were designed to examine movements, territoriality and homing behaviour. They showed movements of Anoplarchus to be rather restricted. Fifty-eight percent of recaptured marked fish showed a homing tendency. Marked fish were seldom found more than 50 feet from where originally captured. Territoriality was of the home-range type during non-breeding times of the year. With the beginning of pair formation in advance of spawning, defended territoriality is shown. Behaviour associated with courtship, parental care and interaction between the sexes subsequent to spawning, is described. Eggs were successfully hatched and the young are described. Spawning takes place in the months of January and February. The female Anoplarchus guards and tends its eggs. The newly hatched larvae show marked positive phototaxis for three to five days, suggesting a planktonic existence during this period; they then become negatively phototactic and seek the bottom. Age and growth were examined by the length-frequency method and otolith analysis. The population was found to be composed of individuals from less than one year of age, to greater than five years of age; representing year classes 1959 to 1963. Females show a slightly faster rate of growth than males and are larger than males at every year of age. The sex ratio favours females over almost the entire range in length exhibited. The value of exponent n, in length-weight relationship, W = c Lⁿ, was found to be 2.98585; log c, -5.31565. The sexes show a similar trend in values of coefficient of condition. The coefficient was at its lowest for specimens collected during the first month of the spawning season. Condition was examined on a size, sex and seasonal basis. / Science, Faculty of / Zoology, Department of / Graduate
80

Marine geology of upper Jervis Inlet

MacDonald, Robert Drummond January 1970 (has links)
Manganese-iron oxide concretions are presently forming on Patrick Sill in upper Jervis Inlet. The marine geology of Patrick Sill and the adjoining basins (Queen's Reach and Princess Royal Reach) was studied to define the environment in which the concretions form. The river at the inlet head is the principal source of sediment to the upper basin. The average grain size of surficial bottom sediments within this basin decreases uniformly with distance from the source. Patrick Sill separates the upper from the lower basin. The sediment distribution pattern within the lower basin differs markedly from the upper basin as there is no dominant source of material but rather many localized sources. Abundant shallow marine faunal remains recovered in deep water sediment samples indicate that sediments deposited as deltas off river and stream mouths periodically slump to the basin floors. Geologic and optical turbidity information for the upper basin can best be explained by slumping from the delta at the inlet head with the initiation of turbidity or density currents. Patrick Sill appears to create a downstream barrier to this flow. The mineralogy of the bottom sediments indicates derivation from a granitic terrain. If this is so, the sediments presently being deposited in both basins are reworked glacial materials initially derived by glacial action outside the present watershed. Upper Jervis Inlet is mapped as lying within a roof pendant of pre-batholithic rocks, principally slates. Patrick Sill is thought to be a bedrock feature mantled with Pleistocene glacial material. The accumulation rate of recent sediments on the sill is low especially in the V-notch or medial depression. The manganese-iron oxide concretions are forming within the depression and apparently nowhere else in the study area. Also forming within the depression are crusts of iron oxide and what are tentatively identified as glauconite-montmorillonoid pellets. The concretions are thought to form by precipitation of manganese-iron oxides on pebbles and cobbles lying at the sediment water interface. The oxide materials are mobile in the reducing environment of the underlying clayey-sand sediment but precipitate on contact with the oxygenating environment of the surficial sediments. The iron crusts are thought to be forming on extensive rocky surfaces above the sediment water interface. The overall appearance and evidence of rapid formation of the crusts suggests they formed from a gel in sea water. Reserves of manganese-iron concretions on Patrick Sill were estimated to be 117 metric tons. Other deposits of concretions have recently been found in other inlets and in the Strait of Georgia but, to date, the extent of these has not been determined. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

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