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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.
31

The threshold of cavitation as a function of temperature and frequency for benzene and ethyl alcohol

Connolly, Walter Curtis, January 1954 (has links)
Thesis--Catholic University of America. / Bibliography: p. 19.
32

A laser cavity design for a relativistic electron-beam pumped rare gas laser

Pearce, Kelly D. January 1986 (has links)
Thesis (M.S.)--University of Michigan, 1986.
33

Study of processing and microstructure of a superplastic 5083 aluminum alloy /

Maestas, Tracy A. January 2002 (has links) (PDF)
Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, March 2002. / Thesis advisor(s): Terry R. McNelley. Includes bibliographical references (p. 57-58). Also available online.
34

Xylem cavitation in newly planted western hemlock (Tsuga heterophylla (Raf.) Sarg.) seedlings /

Kavanagh, Kathleen L., January 1993 (has links)
Thesis (Ph. D.)--Oregon State University, 1994. / Typescript (photocopy). Includes bibliographical references (leaves 85-91). Also available on the World Wide Web.
35

Pressure and noise induced by a cavitating marine screw propeller

Matusiak, Jerzy. January 1992 (has links)
Thesis (Ph. D.)--Helsinki University of Technology, 1992. / Includes bibliographical references (p. 75-79).
36

Comparison of the hybrid and thermal lattice-Boltzmann methods

Olander, Jonathan. January 2009 (has links)
Thesis (M. S.)--Paper Science Engineering, Georgia Institute of Technology, 2010. / Committee Chair: Aidun, Cyrus; Committee Member: Graham, Samuel; Committee Member: Joshi, Yogendra. Part of the SMARTech Electronic Thesis and Dissertation Collection.
37

The onset of ultrasonic cavitation in tap water

Strasberg, Murray, January 1956 (has links)
Thesis--Catholic University of America. / "Footnotes and references": p. 51-55.
38

Development of a Cavitation Erosion Resistant Advanced Material System

Light, Kendrick H. January 2005 (has links) (PDF)
No description available.
39

On the Impact of Spheres onto Liquid Pools and Ultra-viscous Films

Mansoor, Mohammad M. 06 1900 (has links)
The free-surface impact of spheres is important to several applications in the military, industry and sports such as the water-entry of torpedoes, dip-coating procedures and slamming of boats. This two-part thesis attempts to explore this field by investigating cavity formation during the impact of spheres with deep liquid pools and cavitation in thin ultra-viscous films. Part I reports results from an experimental study on the formation of stable- streamlined and helical cavity wakes following the free-surface impact of heated Leidenfrost spheres. The Leidenfrost effect encapsulates the sphere by a vapor layer to prevent any physical contact with the surrounding liquid. This phenomenon is essential for the pacification of acoustic rippling along the cavity interface to result in a stable-streamlined cavity wake. Such a streamlined configuration experiences drag coefficients an order of magnitude lower than those acting on room temperature spheres. A striking observation is the formation of helical cavities which occur for impact Reynolds numbers Re0 ≳ 1.4 × 105 and are characterized by multiple interfacial ridges, stemming from and rotating synchronously about an evident contact line around the sphere equator. This helical configuration has 40-55% smaller overall force coefficients than those obtained in the formation of stable cavity wakes. Part II of this thesis investigates the inception of cavitation and resulting structures when a sphere collides with a solid surface covered with a layer of non-Newtonian liquid having kinematic viscosities of up to v0 = 20,000,000 cSt. The existence of shear-stress- induced cavitation during sphere approach towards the base wall (i.e. the pressurization stage) in ultra-viscous films is shown using a synchronized dual-view high-speed imaging system. In addition, cavitation by depressurization is noted for a new class of non-contact cases whereby the sphere rebounds without any prior contact with the solid wall. Horizontal shear rates calculated using particle image velocimtery (PIV) measurements reveal the apparent fluid viscosity to vary substantially as the sphere approaches and rebounds away from the base wall. A theoretical model based on the lubrication assumption is also solved for the squeeze flow in the regime identified for shear-induced cavity events to investigate the criterion for cavity inception in further detail.
40

Influence of Transplanting Practices on Growth and Embolism Levels For Urban Tree Species

Knight, Patricia Rene 31 March 1997 (has links)
Changes in xylem embolism levels due to drought stress or freezing have been documented for a wide variety of plants. High degrees of tissue water stress which lead to increased levels of embolism are also often cited as factors negatively influencing plant establishment. Embolized xylem elements can potentially lead to restriction of stem water flow, thereby reducing growth. Therefore, this dissertation (5 experiments) was undertaken to determine if certain transplanting practices affect embolism dynamics and plant growth of selected urban tree species. Embolism was estimated based on reductions in hydraulic conductance of harvested stem segments. An initial experiment determined the length of time from tissue harvest to embolism measurement that stem samples may be held in cold storage. Results varied between Fraxinus americana L. (white ash) and Acer rubrum L. x saccharinum L. (hybrid red maple), but data suggested white ash stem samples should not be stored more than one day, especially for between-species comparisons. A greenhouse experiment investigated the growth and embolism levels for container-grown Corylus colurna L. (Turkish hazelnut) seedlings in response to root pruning. Increasing levels of root pruning from 25 to 50% increased embolism, although plant height also increased. There was no fertilizer level x root pruning interaction for embolism. A field-harvest and greenhouse growth experiment investigated the influence of cold storage duration on plant growth and pre- and post-transplant embolism levels. Embolism levels increased with duration of cold storage for Acer rubrum L. (red maple), but not for Crataegus phaenopyrum (L.f.) Medic. (Washington hawthorn). After 15 weeks of growth, however, embolism levels were similar for both species. Growth increased with increased cold storage duration for both species. A field experiment investigated the influence of transplant season and root pruning on plant growth and embolism of Turkish hazelnut and Syringa reticulata (Blume) Hara (tree lilac). Embolism levels just prior to budbreak and days to budbreak were highest for fall-transplanted Turkish hazelnut. Embolism level was unaffected by treatments. No clear relationship between embolism and growth could be determined for either species the first season after transplanting. Other fall-transplanted Turkish hazelnuts, however, had growth reductions that corresponded to increasing embolism levels two years after transplanting. An additional transplanting experiment examined the influence of root severance at transplanting on water relations of red maple. Stem sap flow (in vivo) was reduced within 2 h of harvest, and leaf stomatal conductance was reduced 4 h after harvest. Percent embolism (in vitro) was increased within 24 hr of harvest. Results of these experiments indicate that root pruning, and choice of transplant season can reduce plant growth and increase embolism levels. No clear relationship between embolism and growth reduction was evident. Although embolism dynamics are clearly impacted by transplanting, the implications for transplant success are inconclusive. The role of embolism in transplant success was not clear. / Ph. D.

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