Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 19 of 19 for “"thin liquid film"”.
-
Solidification in a thin liquid film : growing Alq₃ needles via methanol-vapor annealing
… morphology (e.g., the crystallinity) of these thin films. This thesis examines how solvent-vapor annealing of thin, amorphous films of Alq₃-i.e., tris-(8-hydroxyquinoline) aluminum-promotes the growth of single-crystal needles; we explore this system through experiments, modeling, and …
-
Printed electronics and micro-electromechanical systems
… of a suite of printing processes including liquid embossing and offset liquid embossing (OLE). These printing techniques have created resistors, capacitors, and thin-film transistors without etching, vacuum deposition, or high temperatures. Here, the fabrication of all-printed electrostatic …
-
Removal of Bacteria from Solids by Bubbles: Effect of Solid Wettability, Interaction Geometry, and Liquid–Vapor Interface Velocity
… surfaces upon the passage of the first air–liquid interface. In contrast, when a thin liquid film remained between the solid and the bubble (a hydrophilic solid), variable amounts of bacteria remained. Although almost all bacteria were initially removed from hydrophobic solids, many bacteria …
-
Surfactant instabilities on thin films
The deposition of a surfactant drop over a thin liquid film may be accompanied by a fingering instability. In this work, we present experimental results which identify the critical parameters that govern the shape and extend of the fingering phenomena. It was found that the normalized wavelength, …
-
Multiphase Microfluidics for Convective Heat Transfer and Manufacturing
… phenomena will lead to droplet break up. Second, liquid-gas interfaces can enhance heat and mass transfer. If air bubbles, larger than the channel diameter, are confined to a liquid filled microfluidic channel they will elongate into plugs. These plugs are surrounded by a thin liquid film, which …
-
Applications and Methods for Increased Liberation and Separation in the Deinking of Recycled Paper Fiber
… by increasing the disjoining pressure in the thin liquid film (TLF) of water confined between the pigment and fiber while at the same time preventing re-deposition. After the liberation, the pigments are then hydrophobized by adsorbing a surfactant on the surface to greatly improve flotation …
-
Fabrication and buckling of thin spherical shells containing precise geometric imperfections
We revisit the classic problem of buckling of thin spherical shells under uniform pressure and explore the effect that geometric imperfections can have on their buckling behavior. Since the 1960s, numerous theoretical and computational studies have addressed the imperfection sensitivity of buckling …
-
Modeling Bubble Coarsening in Froth Phase from First Principles
… neighboring air bubbles in a froth (or foam), a thin liquid film (TLF) is formed. As the bubbles rise upwards, the TLFs thin initially due to the capillary pressure created by curvature changes. As the film thicknesses (H) reach approximately 200 nm, the disjoining pressure created by surface …
-
Modeling Two-Phase Flow and Heat Transfer in Polygonal Microchannels
… polygonal microchannel filled with a wetting liquid and a long vapor bubble. We model the evaporation, fluid flow, and heat transfer in these devices to derive an analytic solution that captures their performance in terms of two dimensionless parameters. The solution explains the reason behind …
-
Enhanced droplet spreading due to thermal fluctuations
The dynamics of thin film liquid interfaces (< 100 nm) play dominant roles in many macroscale phenomena, such as droplet break up, evaporation of a meniscus, boiling and heat transfer, and thin film dynamics. These processes are can be used in the manufacturing of microelectronics and biomedical …
-
The numerical simulation of thin film flow over heterogeneous substrates
Considerable progress in the understanding of thin film flow over surfaces has been achieved thanks to lubrication theory which enables the governing Navier-Stokes equations to be reduced to a more tractable form, namely a coupled set of partial differential equations. These are solved numerically …
-
Investigating the influence of film formation on the machining performance in an atomization-based cutting fluid spray system
… at cutting temperatures and production of thin chips during machining. Heat generated in the tool-chip contact region is not readily dissipated, leading to a shortened tool life. Various cooling methods have been studied for titanium machining including high pressure coolant application, …
-
Numerical investigation into the effects of multiple bubbles in microchannel flow boiling
… of the working fluid and the evaporation of the thin liquid film present between the channel walls and the vapour bubbles. Many researchers have investigated a wide range of microchannel geometries, orientations and different working fluids and applied heat fluxes. The correlations developed …
-
Convective boiling of refrigerants near the micro-macroscale transition inside plate heat exchangers
… and might not be turbulent. In this research, liquid-vapor two-phase flow regimes and semi-local heat transfer and pressure drop during refrigerant evaporation are studied over varying mass flux, saturation pressure, heat flux, and vapor quality for a commercially available PHE with a 3.4 mm …
-
Engineered interfaces controlling the nucleation and flowability of complex fluids
… such as calcium sulfate are dissolved in the liquid. We demonstrate how nucleation of salt crystals from even an undersaturated solution can cause the critical heat flux to decrease by up to threefold. We analyze the cause of this decrease and propose a passive method for restoring the …
-
Developing a New Mechanical Model for Swarm Development in Myxococcus xanthus & Establishing a Genotype-to-Phenotype Correlation Between Swarm Pattern Formation and Gene Homology
… displayed by all living systems, from biofilm formation and wound healing to embryogenesis. Myxococcus xanthus is a soil bacterium used as a model organism to study biofilm self-organization. It has a relatively large genome and a complex life cycle that involves two distinct phases. M. …
-
Studies of Thin Liquid Films Confined between Hydrophobic Surfaces
… gold surfaces showed a decrease in excess film entropy (£GSf), suggesting that hydrophobic force originates from changes in the structure of the medium (water) confined between hydrophobic surfaces. As a follow-up to the previous study, surface force measurements have been conducted using …
-
Surface Forces in Thin Liquid Films
Thin liquid films (TLFs) of water are ubiquitous in daily lives as well as in many industrial processes. They can be formed between two identical phases, as in colloid films between two macroscopic surfaces and foam films between two air bubbles; and between two dissimilar phases, as in wetting …