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Isentropic ozone transport across the tropopause in the lower stratosphere and upper troposphereJing, Ping, January 2004 (has links) (PDF)
Thesis (Ph. D.)--School of Earth and Atmospheric Sciences, Georgia Institute of Technology, 2004. Directed by Derek M. Cunnold. / Vita. Includes bibliographical references (leaves 109-114).
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Failure mechanism of a brittle layered materialWang, Rentong, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xii, 134 p.; also includes graphics. Includes abstract and vita. Advisor: Noriko Katsube, Dept. of Mechanical Engineering. Includes bibliographical references (p. 121-125).
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Numerical studies of stably stratified planetary boundary-layer flows over topography and their parameterization for large scale numerical modelZhou, Jingnan. January 1997 (has links)
Thesis (M. Sc.)--York University, 1997. Graduate Programme in Earth and Space Science. / Typescript. Includes bibliographical references (leaves 84-91). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL:http://wwwlib.umi.com/cr/yorku/fullcit?pMQ27395.
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Atmospheric boundary-layer flow over topography data analysis and representations of topography /Mengesha, Yoseph Gebrekidan. January 1999 (has links)
Thesis (M. Sc.)--York University, 1999. Graduate Programme in Earth and Space Science. / Typescript. Includes bibliographical references (leaves 138-141). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ39212.
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Upgrading and qualification of a turbulent heat transfer test facilityOdetola, Olumide Folorunso. January 2002 (has links)
Thesis (M.S.)--Mississippi State University. Department of Mechanical Engineering. / Title from title screen. Includes bibliographical references.
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The California coastal jet : synoptic controls and topographically induced mesoscale structure /Cross, Patrick S. January 2003 (has links) (PDF)
Thesis (Ph. D. in Meteorology)--Naval Postgraduate School, March 2003. / Dissertation supervisor: Wendell Nuss. Includes bibliographical references (p. 167-169). Also available online.
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Atomic layer deposition of functional materialsNgo, Thong Quang 01 September 2015 (has links)
Atomic layer deposition (ALD) has emerged as an important technique for depositing thin films in both scientific research and industrial applications. The goal of this work is to integrate functional materials using ALD including high-κ dielectric, LaAlO₃, ferroelectric BaTiO₃, photocatalytic CoO, and room temperature ferromagnetic thin films of Co metal for spin-transfer torque random-access memory applications. The work is also to demonstrate the formation of a quasi-two-dimensional electron gas (2-DEG) at the γ-Al₂O₃/SrTiO₃ heterointerface enabling a method for all-oxide device manufacturing using ALD. High permittivity oxide thin films are needed to replace SiO₂ in complementary metal oxide semiconductor (CMOS) transistors. The replacement of SiO₂ by hafnium oxide-based high-κ materials in CMOS devices in 2007 was a revolutionary development in semiconductor front end of line. The continued device feature shrinking requires higher-κ dielectrics, compared to HfO₂-based materials. Crystalline perovskite oxides, such as SrTiO₃, LaAlO₃, and BaTiO₃, etc. have from high to very high dielectric constant and being proposed to replace HfO₂-based materials in CMOS devices if the leakage problem is resolved. The work explores the monolithic integration of crystalline perovskite oxide films with Si(001) using combined molecular beam epitaxy (MBE) and ALD techniques. Four unit cells of SrTiO₃ were grown directly on Si(001) by MBE and transferred in-situ into the ALD chamber for further depositions. The integration of oxide thin films on Si(001) using the MBE-ALD technique allows us to maintain clean oxide/Si(001) interfaces since low temperatures (180–250 °C) were maintained during the ALD deposition. The goal of my work is also to explore processes to enable area selective deposition of cobalt (II) oxide, CoO. The effectiveness of poly(trimethylsilylstyrene) in selectively inhibiting surface nucleation of CoO on SiO₂ and MgO substrates is demonstrated. Carbon-free cobalt thin films are formed by reducing CoO using Al and Sr metals to scavenge oxygen from CoO. The work explores the ability to control the structure and morphology of the resultant cobalt film by tuning the reduction conditions, allowing us to tune magnetic properties of the cobalt thin film. My work also focuses on the growth of γ-Al₂O₃ on the TiO₂-terminated SrTiO₃ substrate at temperatures higher than 300 °C. The formation of a quasi-2-DEG is found at the γ-Al₂O₃/TiO₂-terminated SrTiO₃ interface. In-situ x-ray photoelectron spectroscopy reveals the presence of Ti³⁺ feature at the heterointerface. Conductivity at the interface was found to be proportional to the amount of Ti³⁺ species. Oxide quasi-2-DEG might provide opportunities for new generations of all-oxide electronic devices using ALD.
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The effect of bed permeability on oscillatory boundary layer flowSparrow, Kathryn January 2013 (has links)
Oscillatory boundary layer flow is found under waves in the near shore region. This region is responsible for large volumes of sediment transport and whilst a large number of studies have investigated the broader problem only a handful of studies have investigated the boundary layer flow in detail. Most of these studies have also only considered boundary layer flow over rough impermeable beds and therefore do not take into account the potential effect of the flow interaction with a permeable bed. Similar studies in other felds of environmental fluid mechanics have concluded that the presence of a permeable bed can lead to significant diff erence in the boundary layer hydrodynamics when compared to the equivalent flow over an impermeable bed. This thesis presents a series of laboratory experiments that have been conducted over an impermeable gravel bed and a permeable gravel bed to identify the differences in the boundary layer hydrodynamics with a particular reference to the differences in the horizontal velocity profile, the shear stress, turbulence and the bed friction factor. The results indicate that a difference exists in the near-bed flow between the two bed cases. The results also demonstrate that the magnitude of the differences vary with flow Reynolds number, so the more energetic the wave the larger the impact of the permeable bed. The bed shear stress and resulting friction factor was found to be 40% greater for the flows over the permeable bed for the most energetic test case whilst the friction factor for the two bed cases for the least energetic test case are similar. The results also indicate that the permeable bed introduces an unexpected asymmetry in the flow cycle. This is attributed to the high vertical velocities that have been observed. A second series of experiments have been conducted to shed light on the interaction between the flow above the bed and within the bed to help explain the results from the initial gravel-bed experiments. The second series of experiments have been conducted over a regular permeable bed that allows for velocity measurements within the pores. The results indicate that the horizontal velocity, shear stress and turbulence all display signs of being effected by the exchange of flow, or ventilation, that naturally occurs.
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Boundary layer receptivity mechanisms relevant to laminar flow control.Choudhari, Meelan. January 1990 (has links)
Receptivity processes by which free-stream acoustic waves generate instability waves in boundary layers are investigated. Concentration is placed on mechanisms associated with local regions of short scale variation in wall suction or admittance distribution. These mechanisms are relevant to laminar flow control technology, in which suction is utilized to control the growth of boundary layer instabilities. The receptivity process requires a transfer of energy from the long wavelength of the free-stream disturbance to the short wavelength of the instability wave. In the case of wall suction, this occurs through the unsteady modulation, by the acoustic wave, of the short scale mean flow variation due to the steady wall suction. In the wall admittance mechanism, the boundary condition for the unsteady motion contains a short scale variation which directly scatters energy from the acoustic wave into the instability wave. The latter mechanism does not require a short scale adjustment in the mean boundary layer. Time harmonic, two and three-dimensional interactions are analyzed using the asymptotic, high Reynolds number, triple deck structure. The influence of subsonic compressibility is examined for the case of two-dimensional interactions, and a similarity transform is found which reduces the problem to an equivalent incompressible flow. For three-dimensional interactions, a similarity transform is possible only in the Fourier transform wavenumber space, and in the equivalent two-dimensional problem the frequency is complex. However, in many cases of practical interest, the imaginary component of this frequency is quite small and can be neglected. The acoustic wave orientation and the geometry of the wall suction or admittance distribution are found to significantly influence the amplitude of the generated instability wave. For an isolated, three-dimensional region of wall suction or admittance, instability wave growth is confined to a downstream, wedge shaped region. The saddle point method is utilized to calculate the characteristics of this instability wave pattern. In some ranges of parameter space, two saddle points are found to make comparable contributions. The instability wave pattern in these directions exhibits a beat phenomenon, due to constructive and destructive interference of the contributions from the two saddle points.
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INTERNAL LAMINAR HEAT TRANSFER TO A GAS WITH TEMPERATURE DEPENDENT PROPERTIESSwearingen, Thomas Burke, 1931- January 1969 (has links)
No description available.
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