Physics Commons^™

The Mechanism Of Self-Organized Beating Of Cilia, Jyothish Vidyadharan

Dissertations - ALL

No abstract provided.

Rigidity And Fluidity In Living And Nonliving Matter, Jorge Hernan Lopez

Dissertations - ALL

Many of the standard equilibrium statistical mechanics techniques do not readily apply to non-equilibrium phase transitions such as the fluid-to-disordered solid transition found in repulsive particulate systems. Examples of repulsive particulate systems are sand grains and colloids. The first part of this thesis contributes to methods beyond equilibrium statistical mechanics to ultimately understand the nature of the fluid-to-disordered solid transition, or jamming, from a microscopic basis.

In Chapter 2 we revisit the concept of minimal rigidity as applied to frictionless, repulsive soft sphere packings in two dimensions with the

introduction of the jamming graph. Minimal rigidity is a purely combinatorial …

The Non-Erythroid Membrane Skeleton And Its Role In Mechanotransduction, Eleni Kinfe Degaga

Dissertations - ALL

The thesis is concerned with questions regarding cellular bio-mechanics and cell surface interactions. A particular focus is thereby on the role of the spectrin membrane skeleton in transducing forces to and from non-erythroid mammalian cells. This spectrin based membrane skeleton has been the focus of much study in the context of red blood cells, as it determines their mechanical properties due to the lack of an extended actin based cytoskeleton. In stark contrast, the corresponding structure in non-erythroids is much less studied and understood, although it seems to play important roles in organization of membrane associated proteins, cellular mechanics, adhesion, …

Electron And Hole Drift Mobility Measurements On Thin Film Cdte Solar Cells, Qi Long, Steluta A. Dinca, Eric A. Schiff, Ming Yu, Jeremy Theil

Physics - All Scholarship

We report electron and hole drift mobilities in thin film polycrystalline CdTe solar cells based on photocarrier time-of-flight measurements. For a deposition process similar to that used for high-efficiency cells, the electron drift mobilities are in the range of 10–100 cm²/Vs, and holes are in the range of 1–10 cm²/Vs. The electron drift mobilities are about a thousand times smaller than those measured in single crystal CdTe with time-of-flight; the hole mobilities are about ten times smaller. Cells were examined before and after a vapor phase treatment with CdCl₂; treatment had little effect on …

Investigating Drift Mobilities In Cadmium Telluride Solar Cells, Daniel Goldman

Honors Capstone Projects - All

See Abstract within Capstone document

Study Of Edgeless Timepix Pixel Devices, Dylan G. Hsu

Honors Capstone Projects - All

Silicon micropattern devices are crucial components of detector systems designed to study decays of exotic subatomic particles containing beauty and charm quarks. Among the technologies under consideration for use in future particle physics experiments are edgeless silicon pixel detectors. In these devices a state-of-the-art fabrication process is used to create sensors with a nearly full active area, as compared to conventional sensors which have a “guard ring” which is a dead region at the sensor periphery. Prototypes used for the study described in this paper were designed and fabricated by VTT Technical Research Centre of Finland. In a test beam …

Coalescence Of Bubbles And Drops In An Outer Fluid, Joseph Paulsen, Remi Carmigniani, Anerudh Kannan, Justin C. Burton

Physics - All Scholarship

When two liquid drops touch, a microscopic connecting liquid bridge forms and rapidly grows as the two drops merge into one. Whereas coalescence has been thoroughly studied when drops coalesce in vacuum or air, many important situations involve coalescence in a dense surrounding fluid, such as oil coalescence in brine. Here we study the merging of gas bubbles and liquid drops in an external fluid. Our data indicate that the flows occur over much larger length scales in the outer fluid than inside the drops themselves. Thus, we find that the asymptotic early regime is always dominated by the viscosity …

Multiple Transient Memories In Experiments On Sheared Non-Brownian Suspensions, Joseph Paulsen, Nathan C. Keim, Sidney R. Nagel

Physics - All Scholarship

A system with multiple transient memories can remember a set of inputs but subsequently forgets almost all of them, even as they are continually applied. If noise is added, the system can store all memories indefinitely. The phenomenon has recently been predicted for cyclically sheared non-Brownian suspensions. Here we present experiments on such suspensions, finding behavior consistent with multiple transient memories and showing how memories can be stabilized by noise.