[After a Fashion, August 17, 2005] (open access)

[After a Fashion, August 17, 2005]

Article about do-it-yourself fashion, the closing of Roy's taxi company, Austin Circle of Theaters, and several events happening around Austin, Texas.
Date: August 17, 2006
Creator: Moser, Stephen MacMillan
System: The UNT Digital Library
DEUTERIUM, TRITIUM, AND HELIUM DESORPTION FROM AGED TITANIUM TRITIDES. PART II. (open access)

DEUTERIUM, TRITIUM, AND HELIUM DESORPTION FROM AGED TITANIUM TRITIDES. PART II.

Six new samples of tritium-aged bulk titanium have been examined by thermal desorption and isotope exchange chemistry. The discovery of a lower temperature hydrogen desorption state in these materials, previously reported, has been confirmed in one of the new samples. The helium release of the samples shows the more severe effects obtained from longer aging periods, i.e. higher initial He/M ratios. Several of the more aged samples were spontaneously releasing helium. Part I discussed the new results on the new lower temperature hydrogen desorption state found in one more extensively studied sample. Part II will discuss the hydrogen/helium release behavior of the remaining samples.
Date: August 17, 2006
Creator: Shanahan, K & Jeffrey Holder, J
System: The UNT Digital Library
Modeling Gas-Phase Transport in Polymer-Electrolyte FuelCells (open access)

Modeling Gas-Phase Transport in Polymer-Electrolyte FuelCells

In this transaction, the equations and methodology for modeling convection and ordinary, Knudsen, and pressure diffusion of gases in a fuel-cell gas-diffusion layer are described. Some results examining the magnitudes of the various terms are also made. This derivation results in a self-consistent description of the various transport mechanisms and is robust for numerical solutions, especially for conditions involving different flow regimes or where the regime is not known a priori.
Date: August 17, 2006
Creator: Weber, A.Z. & Newman, J.
System: The UNT Digital Library
Potential COntrol Under Thin Aqueous Layers Using a Kelvin Probe (open access)

Potential COntrol Under Thin Aqueous Layers Using a Kelvin Probe

Kelvin Probes can be modified to control as well as monitor potential. The design and operation of two different Kelvin Probe Potentiostats (KPPs) are described in this paper. One approach uses a permanent magnet and double coil to oscillate the needle at a fixed frequency, an AC backing potential, and software analysis and control schemes. This technique can also control the distance between the tip and sample, thereby tracking the topography of the sample. Both KPPs were used to make measurements on Type 304L stainless steel under thin layers of electrolyte. Cathodic polarization curves exhibited a limiting current density associated with oxygen reduction. The limiting current density varied with solution layer thickness over a finite range of thickness. Anodic polarization curves on 304L in a thin layer of chloride solution resulted in pitting corrosion. The breakdown potential did not vary with solution layer thickness. However, the thin layer was observed to increase in volume remarkably during pit growth owing to the absorption of water from the high humidity environment into the layer with ionic strength increased by the pit dissolution. The open circuit potential (OCP) and solution layer thickness were monitored during drying out of a thin electrolyte layer. Pitting …
Date: August 17, 2006
Creator: Frankel, G. S.; Maier, B.; Stratman, M.; Rohwerder, M.; Michalik, A.; Dora, J. et al.
System: The UNT Digital Library