M.S.

Because of the increased demand for low calorie products, more products are being sweetened with artificial sweeteners. Perceived sweetness may be affected by other food ingredients, such as hydrocolloids. The purpose of this study was to examine the effects of xanthan gum, carboxymethyicellulose-low, and carboxymethylcellulose-medium on the attributes of a lemon flavored beverage sweetened with an artificial sweetener. Each hydrocolloid was added to the beverages to attain the following viscosities - 10 cps, 15 cps, and 20 Ctps. The table top formulations of artificial sweeteners used to sweeten the beverage samples were Sweet One® (contains acesulfame-K) and Equal® (contains aspartame). A modified Quantitative Descriptive Analysis method was used as the sensory evaluation technique to determine the intensity of sourness, sweetness, lemon flavor, bitterness, and aftertaste in the beverages of varying viscosities. In the samples containing Sweet One®, CMC-L increased sweetness whereas in the samples containing Equal®, sweetness first decreased significantly before increasing with increasing viscosity. CMC-M did not Significantly affect the sweetness of either sweetener although it tended to decrease the sweetness of Equal®. CMC-L and CMC-M decreased lemon flavor and sourness in the samples with both sweeteners; CMC-L decreased the intensity of these attributes more than CMC-M. The only significant change caused by the addition of xanthan gum to the beverages was a decrease in the sweetness of the samples sweetened with Equal®. Xanthan gum affected the attributes of the lemon flavored beverages the least whereas CMC-L had the greatest effect on the attributes. / Master of Science

A one-dimensional infiltration/cure model was developed to simulate fabrication of advanced textile composites by the resin film infusion process. The simulation model relates the applied temperature and pressure processing cycles, along with the experimentally measured compaction and permeability characteristics of the fabric preforms, to the temperature distribution, the resin degree of cure and viscosity, and the infiltration flow front position as a function of time. The model also predicts the final panel thickness, fiber volume fraction, and resin mass for full saturation as a function of compaction pressure. The infiltration model is based on D’arcy’s law for flow through porous media. Composite panels were fabricated using the RTM film infusion technique from knitted, knitted/stitched, and 2-D woven carbon preforms and Hercules 3501-6 resin. Prior to fabrication, the deflection and permeability of the preforms were measured as a function of compaction pressure. Measurements of the temperature distribution, the resin viscosity and degree of cure, and the infiltration flow front position were compared with the RTM simulation model results. The model predictions were within 12% of the experimental results. Fabric composites were fabricated at different compaction pressures and temperature cycles to determine the effects of the processing on the properties. The composites were C-scanned and micrographed to determine the quality of each panel. Composite panels fabricated using different temperature cycles to the same state of cure and similar compaction pressures were found to have similar compressive and shear properties. Advanced cure cycles, developed from the RTM simulation model, were utilized to reduce the total cure cycle times by a factor of 3 and the total infiltration times by a factor of 2. / Master of Science

H. pylori is one of the most significant discoveries in gastroenterology in the past century. It is associated with a wide range of gastroduodenal pathologies and gastric cancer. Antibiotic resistance in H. pylori has emerged as a significant clinical problem. The body of work contained within this dissertation was carried out to investigate an alternative therapy based on observations of the traditional therapy for gastric disease in the Middle East. One of these traditional therapies centres on plants belonging to the Pistacia genus. This study represents the first reported investigation into the composition and biological activity of the trunk bark exudates of Pistacia atlantica Kurdic (P. a. Kurdica), Pistacia atlantica Mutica (P. a. Mutica) and Pistacia atlantica Cabolica (P. a. Cabolica), resinous gums that have been termed here ‘Kurdica Gum’, ‘Mutica Gum ’ and ‘Cabolica Gum ’ respectively. The antimicrobial screening of the trunk exudates of the genus Pistacia led to the characterization of the most active fraction of the Kurdica gum. This fraction was subsequently subjected to sub-fractionation leading to the discovery of fundamentally new information that went beyond H. pylori, expanding the original parameters of the project. The extent of these findings suggests that new classes of antibiotics might have been discovered. Primary studies on their structure and potential mechanism of action has been undertaken. Thirteen novel antimicrobial agents were identified. Based on the characteristics of these isolated fractions, 50 new compounds were modelled; of which 30 hypothetically have an MIC consistent with contemporary antibiotics and could represent viable lead compounds for commercial development. / Doctor of Philosophy

Thesis (M.S.M.E.)--University of Delaware, 2006. / Principal faculty advisor: James Glancey, Dept. of Bioresources Engineering. Includes bibliographical references.

No description available.

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 153-159). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 153-159). Also available on the Internet.

Thesis (Ph. D.)--Institute of Paper Chemistry, 1959. / Includes bibliographical references (p. 92-95).

Thesis (Ph. D.)--Institute of Paper Chemistry, 1934. / Includes bibliographical references (leaves 48-51).