No description available.

In view of its varied concepts and interpretations, and because of the discrepancies produced by the previous utilization of polydispersed dextrans, a study using extremely narrow-range molecular weight dextran fractions was initiated to reevaluate and consolidate some of the aspects of capillary permeability. A portion of the study was performed under decreased barometric pressure in order to clarify further some of the mechanisms involved in particulate transfer across the capillary endothelial membranes. Gel filtration procedures augmented the study as an assessment of the polydispersity effects of the dextrans employed.

Typescript. / Digitized by Kansas Correctional Industries

Call number: LD2668 .T4 1950 P46 / Master of Science

No description available.

Digitized by Kansas Correctional Industries

Thesis (M.S.)--Ohio State University, 1982. / Includes bibliographical references (leaves 119-124). Available online via OhioLINK's ETD Center

The problem of evaluating permeability anisotropy in the Tilje Formation, Heidrum field, offshore mid-Norway, has been investigated by the Statoil Research Centre by a detailed combination of the geological and petrophysical data. The large diversity and contrasting levels of heterogeneity within depositional facies observed in the Tilje Formation reflect complicated patterns of deposition along deltaic shorelines and the adjunct shelf of a tidally influenced, narrow seaway. Permeability anisotropy can alter the directionality of the fluid flow in the reservoir, and thereby affect the most important exploration procedures: perforation, water and gas injection, production, and estimation of the field resource. This thesis presents a simplified method of modeling permeability anisotropy in the Tilje Formation.

Starch and chitosan films are both known to be effective barriers to gas permeation. Being naturally abundant, renewable, and biodegradable, starch and chitosan films have the potential to replace petroleum-based materials for food packaging applications. However, the gas permeability of starch-chitosan blend films has not been studied extensively. In order to characterize starch-chitosan blend films for food packaging application, the permeabilities of N2, O2 and CO2 in the blend films were studied at different operating conditions (e.g., relative humidity, chitosan content in the films, cross membrane pressure, and temperature). The gas permeation was measured using the traditional volumetric technique. Gas permeation through films containing different amounts of chitosan was measured at ambient temperature and at a cross membrane pressure of 60psi. In addition, pure chitosan was also tested at a high relative humidity where the gas was saturated with water vapor. The effects of temperature and cross membrane pressure on the gas permeability were studied with starch-chitosan blend films and pure chitosan films as well. It was found that an increase in pressure and/or temperature increased the permeability, and the temperature dependence of permeability followed the Arrhenius relation, from which activation energy of permeation was evaluated. The starch-chitosan blend films with approximately 60wt% chitosan showed the best gas barrier property and the highest activation energy for permeation.

Starch and chitosan films are both known to be effective barriers to gas permeation. Being naturally abundant, renewable, and biodegradable, starch and chitosan films have the potential to replace petroleum-based materials for food packaging applications. However, the gas permeability of starch-chitosan blend films has not been studied extensively. In order to characterize starch-chitosan blend films for food packaging application, the permeabilities of N2, O2 and CO2 in the blend films were studied at different operating conditions (e.g., relative humidity, chitosan content in the films, cross membrane pressure, and temperature). The gas permeation was measured using the traditional volumetric technique. Gas permeation through films containing different amounts of chitosan was measured at ambient temperature and at a cross membrane pressure of 60psi. In addition, pure chitosan was also tested at a high relative humidity where the gas was saturated with water vapor. The effects of temperature and cross membrane pressure on the gas permeability were studied with starch-chitosan blend films and pure chitosan films as well. It was found that an increase in pressure and/or temperature increased the permeability, and the temperature dependence of permeability followed the Arrhenius relation, from which activation energy of permeation was evaluated. The starch-chitosan blend films with approximately 60wt% chitosan showed the best gas barrier property and the highest activation energy for permeation.