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1 
Rate of condensation of water vapor under vacuumGibson, Lowell Charles, January 1952 (has links)
Thesis (Ph. D.)University of WisconsinMadison, 1952. / Typescript. Includes abstract and vita. eContent providerneutral record in process. Description based on print version record. Includes bibliographical references (leaves 9193).

2 
Dropwise condensation,Fatica, Nicholas, Katz, Donald La Verne, January 1949 (has links)
N. Fatica's ThesisUniversity of Michigan. / "Reprinted from Chemical engineering progress, November, 1949."

3 
Experimental investigations towards production of hyperpolarized xenon129 through the condensed stateBalakishiyeva, Durdana Nazim. January 2006 (has links)
Thesis (PH.D.)  Syracuse University, 2006 / "Publication number AAT 3251759."

4 
Device physics of hydrogenated amorphous silicon solar cellsLiang, Jianjun. January 2006 (has links)
Thesis (PH.D.)  Syracuse University, 2006 / "Publication number AAT 3251776."

5 
The effects of salts on polyelectrolyte systemsZissu, Jonathan Adam 01 January 1999 (has links)
The effects of salts on the behavior of polyelectrolyte systems were investigated. The phase behavior of polyelectrolyte solutions in the presence of added salt was calculated by combining the free energies due to FloryHuggins mixing and DebyeHuckel electrostatics, with both terms modified for our polyelectrolyte solutions. Using the calculated phase diagrams, we found that most results give a typical polymersolventnonsolvent phase diagram, with the solvent acting as a “nonsolvent” (since we assume that the polymersolvent interaction parameter, χ, is positive) and the dissociated salt acting as a “solvent”. However, for high charges of the salt ions, we found a completely different phase diagram, one which can be explained by a “salting out effect” where the addition of salt over a certain concentration threshold causes complete phase separation over all concentrations of polymer and solvent. Also, the density and repulsive force profiles for a system comprised of two parallel, planar, uncharged surfaces uniformly covered with poly electrolyte brushes in an electrolyte solution was calculated using a computational enumeration of a onedimensional random walk model. For large surface separations, we found three different density profiles: a Gaussian regime when κ is large, a stretched regime when κ is intermediate in value, and a “pancake” regime, with chains collapsed onto their grafted surface, when κ is small. For small surface separations, the first two regimes are replaced with an interpenetrating regime, where the density is essentially uniform across the entire region between the surfaces. For intermediate surface separations, the repulsive force scales as exp[special characters omitted] unlike what is expected using GouyChapman theory.

6 
Simulations of stronglyinteracting fermion systemsBurovski, Evgeni 01 January 2007 (has links)
A generic scenario of a crossover between weakcoupling and strongcoupling limits of a manybody quantum system is studied. Powerful numerical methods of investigating the strongly correlated regime are developed and applied to answering a number of important questions of the strongly correlated fermions physics. The internal structure of an exciton in an insulating medium is studied throughout the crossover between the (analytically solvable) strong and weakcoupling limits. In the intermediate regime, accurate results for the exciton ground state are obtained and used to establish the limits of applicability of the corresponding limiting cases for the first time. A novel combination of the diagrammatic determinant Monte Carlo and the worm algorithm is developed and used for investigating the unitarity regime of the BECBCS crossover via simulating the dilute FermiHubbard model. Superfluid phase transition and thermodynamic properties of the normal state are characterized for both lattice fermions and continuum unitary Fermi gas. The relation to current experiments with trapped ultracold quantum gases is discussed.

7 
Charge transport on the nanometer scale: Experimental and numerical investigationsMcCarthy, Kevin D 01 January 2007 (has links)
This thesis will review my experimental efforts in measuring charge transport using onchip and scanning probe techniques at the nanometer size scale, as well as numerical investigations into the charge transport of a single molecular C60 transistor [H. Park et al., Nature (London) 407, 57 (2000)]. Experimentally, I report on efforts to utilize onchip and scanning probe electronic interfacing for chemical and biological systems for which we expect charge transport measurements to reveal interesting and technologically relevant information. Theoretically, I show how the microscopic force fields in nanostructures can influence their electronic dynamics using the example calculations of a molecular single electron transistor (SET) with a single mode, linearly coupled vibrational environment. These calculations predict a novel negative differential conductance (NDC) effect due to the FranckCondon quantum dynamics of charged, "vibrating" SET islands in a mechanically soft potential well.

8 
Phase diagrams of stoichiometric polyelectrolytesurfactant complexesLeonard, Michael J 01 January 2005 (has links)
When a watersoluble polyelectrolyte is combined with an oppositelycharged surfactant solution at a stoichiometric charge ratio, selfassembly into a highly ordered, waterinsoluble complex can occur. These materials exhibit phase structures which are analogous to their pure surfactant components, and significant effort has been made in the past several decades to characterize, predict, and control the various morphologies observed in these systems. However, a truly comprehensive understanding of the phase behavior of these systems is lacking. The purpose of this project is to establish general phase diagrams for selfassembled, stoichiometric poly(acrylatecoacrylamide)cetyltrimethylammonium halide (PAAmCTAX) complexes by studying phase structure as a function of ionic strength, salt type, polyelectrolyte charge density, temperature, and applied osmotic pressure with smallangle Xray scattering (SAXS). By developing a deeper understanding of the phase behavior and energetics of such a model system, it is hoped that general trends can be extrapolated to other polyelectrolytesurfactant systems, such as polysaccharidesurfactant systems, which may provide the means to template desired structures in nanoporous, biocompatible matrices. Materials such as these may be attractive targets for drug delivery and nanoscale separation applications.

9 
Weakly interacting Bose gases in the fluctuation regionRuebenacker, Oliver A 01 January 2005 (has links)
We study the superfluid transition of weakly interacting Bose gases, classical fields and related systems in two dimensions, where it is a BerezinskiiKosterlitzThouless transition, and in three dimensions, where it is a U(1) transition accompanied by the onset of BoseEinstein condensation. We show that for small interaction strength U, these systems can be described by a :Ψ:4 model based on classical complex fields and we establish universal behavior among systems of different microscopical details, such as classical and quantum, continuous and lattice. By numerical simulations of the classical lattice field, using Worm Algorithm, we solve all relevant thermodynamical functions of this system, which are density, condensate density (in 3D), superfluid density and quasicondensate. Through universality considerations, we can translate these results to all systems which can be described by a :Ψ:4 model based on a classical complex field. Our results cover the fluctuation region and extend into mean field and critical region, where we connect them to results of mean field theory and renormalization group theory respectively. We also establish that the quasicondensate, which exists in two and three dimensions, is a basis for a more accurate mean field theory treatment than the condensate, which exists only in three dimensions.

10 
BoseEinstein in two dimensional trapsFernandez, Juan Pablo 01 January 2004 (has links)
The fact that twodimensional interacting trapped systems do not undergo BoseEinstein Condensation (BEC) in the thermodynamic limit, though rigorously proved, is somewhat mysterious because all relevant limiting cases (zero temperature, small atom numbers, noninteracting particles) suggest otherwise. We study the possibility of condensation in finite trapped twodimensional systems. We first consider the ideal gas, which incorporates the inhomogeneity and finite size of experimental systems and can be solved exactly. A semiclassical selfconsistent approximation gives us a feel for the temperature scales; diagonalization of the onebody density matrix confirms that the condensation is into a single state. We squeeze a threedimensional system and see how it crosses over into two dimensions. Meanfield theory, our main tool for the study of interacting systems, prescribes coupled equations for the condensate and the thermal cloud: the condensate receives a full quantummechanical treatment, while the noncondensate is described by different schemes of varying sophistication. We analyze the T = 0 case and its approach to the thermodynamic limit, finding a criterion for the dimensionality crossover and obtaining the coupling constant of the twodimensional system that results from squeezing a threedimensional trap. We next apply a semiclassical HartreeFock approximation to purely twodimensional finite gases and find that they can be described either with or without a condensate; this continues to be true in the thermodynamic limit. The condensed solutions have a lower free energy at all temperatures but neglect the presence of phonons within the system and cease to exist when we allow for this possibility. The uncondensed solutions, in turn, are valid under a more rigorous scheme but have consistency problems of their own. Pathintegral Monte Carlo simulations provide an essentially exact description of finite interacting gases and enable us to study highly anisotropic systems at finite temperature. We find that our twodimensional HartreeFock solutions accurately mimic the surface density profile and predict the condensate fraction of these systems; the equivalent interaction parameter is smaller than that dictated by the T = 0 analysis. We conclude that, in twodimensional isotropic finite trapped systems and in highly compressed threedimensional gases, there is a phenomenon resembling a condensation into a single state.

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