<p> This dissertation is a compilation of research results of extensive Fast Scanning Calorimetry studies of two non-crystalline materials: Toluene and Water. </p><p> Motivation for fundamental studies of non-crystalline phases, a brief overview of glassy materials and concepts and definitions related to them is provided in Chapter 1. Chapter 2 provides fundamentals and details of experimental apparata, experimental protocol and calibration procedure. </p><p> Chapter 3 &amp; 4 provides extensive studies of stable non-crystalline toluene films of micrometer and nanometer thicknesses grown by vapor deposition at distinct deposition rates and temperatures and probed by Fast Scanning Calorimetry. Fast scanning calorimetry is shown to be extremely sensitive to the structure of the vapor-deposited phase and was used to characterize simultaneously its kinetic stability and its thermodynamic properties. According to our analysis, transformation of vapor -deposited samples of toluene during heating with rates in excess 100,000 K/s follows the zero-order kinetics. The transformation rate correlates strongly with the initial enthalpy of the sample, which increases with the deposition rate according to sub-linear law. Analysis of the transformation kinetics of vapor deposited toluene films of various thicknesses reveal a sudden increase in the transformation rate for films thinner than 250 nm. The change in kinetics correlates with the surface roughness scale of the substrate, which is interpreted as evidence for kinetic anisotropy of the samples. We also show that out-of-equilibrium relaxation kinetics and possibly the enthalpy of vapor-deposited (VD) films of toluene are distinct from those of ordinary supercooled (OS) phase even when the deposition takes place at temperatures above the glass softening (Tg). The implications of these findings for the formation mechanism and structure of vapor deposited stable glasses are discussed. </p><p> Chapter 5 and 6 provide detailed Fast Scanning Calorimetry studies of amorphous solid water in bulk and confining geometry (ultrathin films and nano-aggregates). Bulk-like water samples were prepared by vapor-deposition on the surface of a tungsten filament near 140 K where vapor-deposition results in low enthalpy glassy water films. The vapor deposition approach was also used to grow nano-aggregates (2- 20 nm thick) and multiple ultrathin (approximately 50 nm thick) water films alternated with benzene and methanoic films of similar dimensions. When heated from cryogenic temperatures, the ultrathin water films underwent a well manifested glass softening transition at temperatures 20 degrees below the onset of crystallization. The thermograms of nano-aggregates of ASW films show two endotherms at 40 and 10 K below the onset temperatures of crystallization. However, no such transition was observed in bulk-like water samples prior to their crystallization. These results indicate that water in confined geometry demonstrates glass softening dynamics which are dramatically distinct from those of the bulk phase. We attribute these differences to water's interfacial glass transition which occurs at temperatures tens of degrees lower than that in the bulk. Implications of these finding for past studies of glass softening dynamics in various glassy water samples are discussed in chapter 5 and 6.</p>

<p> The NPDGamma Experiment is measuring the parity-violating correlation A_&gamma; between neutron spin and gamma momentum in the radiative capture of a polarized cold neutron beam on a cryogenic liquid parahydrogen target. This measurement is expected to give insight into theories that incorporate the weak interaction into what is primarily a strongly interacting system. This dissertation discusses the operation and characterization of the liquid hydrogen target, including the calibration of the instrumentation that monitors the state of the hydrogen. An important consideration is the fact that for safety reasons the instrumentation in direct contact with the hydrogen is limited, and so a detailed understanding of the target design and of the properties of hydrogen is required in order to interpret the state of the system. For this experiment, it is essential that the hydrogen be kept mostly in the para state in order to prevent the beam from being significantly depolarized before capture. Since the uncatalyzed conversion rate is slow, an ortho-para conversion loop is used to promote conversion from the room temperature orthohydrogen fraction to the fraction associated with the temperatures of the cryogenic vessel. In addition to the calibration and characterization studies, a method is introduced for placing an empirical limit on the deviation of the orthohydrogen fraction inside the vessel from the desired level associated with the temperature of the ortho-para conversion catalyst and vessel. This method, which does not require precise knowledge of the parahydrogen cross section, involves observing the transmission of the beam through the target while the rate of flow of hydrogen through the ortho-para conversion loop is changed. In addition to the studies of the hydrogen target, this dissertation discusses a calibration of some ³He ion chambers that monitor the flux of the neutron beam and that are used to perform beam transmission measurements. This calibration, which involves a study of the noise inherent in the signal due to neutron capture, does not involve comparison to a separate calibrated detector.</p>

Thesis (Ph.D.)--Drexel University, 2007. / Includes abstract and vita. Includes bibliographical references (leaves 157-167).

Thesis (M.S.)--University of North Texas, May, 2007. / Title from title page display. Includes bibliographical references.

Thesis (M.S.)--Cleveland State University, 2007. / Abstract. Title from PDF t.p. (viewed on May 8, 2008). Includes bibliographical references (p. 80-82). Available online via the OhioLINK ETD Center. Also available in print.

Thesis (Ph. D.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 163-168).

Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 205-214). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 205-214). Also available on the Internet.

Thesis (Ph. D.)--Florida State University, 2004. / Advisor: Dr. Steven W. Van Sciver, Florida State University, College of Engineering, Dept. of Mechanical Engineering. Title and description from dissertation home page (viewed Sept. 22, 2004). Includes bibliographical references.

Thesis (Ph.D.)--University of California, Berkeley, 1962. / "UC-4 Chemistry" -t.p. "TID-4500 (16th Ed.)" -t.p. Includes bibliographical references (p. 70-72).