In the present study, the textural changes induced in Chinese waterchestnuts by physical and chemical means were of prime concern. After being subjected to chemical and heat treatments, the corms were analyzed to relate the chemical changes with the physical changes in the corms. Chinese waterchestnuts were peeled, filled in cans with one hundred ml of various concentrations of hydrochloric acid and sodium hydroxide, and heated in the retort for one hour at 240°F (115.6°C). Distilled water was used for the control samples. Physical and chemical examinations followed, and the results of the texture measurements were compared with the chemical composition of the corms. A physical measurement of texture was obtained by using the Maryland Shear-press. The drained weights, total solids, alcohol insoluble solids, ash, total sugars, cellulose, starch, total pectins including three pectic fractions, phosphorus, calcium and potassium were determined. Measurements of pH, degrees Brix, and color intensity were made on the processed liquid. The results indicated the following conclusions: 1. Processing in both acid and alkali had a definite softening effect on the Chinese waterchestnut corm. 2. The highest correlation was obtained between texture (as measured by maximum force and total work) and cellulose in both the acid and alkali series. 3. The hydrolysis of cellulose and starch was more complete in the acid series. 4. A linear relationship existed between the pH of the acid series and texture. 5. The samples processed in acid showed more consistent trends than did the alkali processed samples. 6. There was a darkening in color as the concentration of both the acid and alkali increased. 7. The percentages of total solids and AIS showed a definite trend when compared with the texture measurements. 8. The relationship between firmness of the corms and the pectic substances in this study was a complex relationship due to the reactive nature of the pectic compounds. / Graduation date: 1964

Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1989. / Includes bibliographical references. / Microfiche. / xiii, 145 leaves, bound ill. (some col.) 29 cm

<p>Table Muntain Group has been identified as one of the major Regional Aquifers in South Africa. the vast distribution of it leads to a great diversity in its hydrogeological properties, which influences the dynamics of recharge, discahrge and storage, resulting in groundwater occurrances unevenly distributed in TMG area. Thereby a proper regional groundwater resource evaluation focusing on the quantification of recharge, discharge and storage, is of most importance for the efficient groundwater utilization and management of TMG aquifers.The response of TMG aquifer to pumping stress is studied in Kammanassie Mountains by groundwater flow modeling. 3D hydrogeological model is constructed, which helps to improve the understanding of the conceptual hydrogeological model. Detailed groundwater-related analyses are performed on the basis of previous data sets. Groundwater numerical model is then established according to the conceptual model to stimulate the aquifers responses to various pumping scenarios. Some general data processing approaches are also develooped in this study that can be expected to apply to analog studies.</p>

The aim of this project was to develop a method for the determination of epichlorohydrin in drinking water. First, epichlorohydrin was studied on gas chromatography (GC) to determine the retention time. Then, epichlorohydrin was used to optimise the GC parameters : best detector, detector temperature, total detector flow, injector temperature and column temperature program. Secondly, epichlorohydrin was extracted by Solid Phase Micro-Extraction (SPME) and by Solid Phase Extraction (SPE) and analysed by GC to optimise the extraction mode parameters : SPME extraction mode, salt saturation, fibre selection, sample temperature, fibre placement, stirring and vibration, extraction time ; SPE tube selection, volume of extraction, extraction flow rate, salt saturation, drying process, solvent of elution, volume of solvent. Thirdly, the limit of detection of both extraction modes by GC was looked at to decide on the best extraction technique for epichlorohydrin. Fourth, epichlorohydrin was extracted by SPME direct immersion and analysed by gas chromatography/mass spectroscopy (GC/MS). A calibration curve was obtained with the analyses of Milli-Q water sample spiked with epichlorodydrin. A limit of detection was determined at 0.38 μg/L. Finally, water samples from the Adelaide distribution system were analysed by GC/MS through two columns but epichlorohydrin could not be separated from bromodichloromethane present in drinking water from the disinfection process. / Thesis (MEng(HydrologyWaterResources))--University of South Australia, 2003.

Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Thesis (M.A., Landscape Architecture)--University of Arizona, 1990. / Includes bibliographical references.

Thesis (M.S. - Renewable Natural Resources)--University of Arizona. / Includes bibliographical references.

Thesis (M.S. - Hydrology and Water Resources)--University of Arizona. / Includes bibliographical references.

Thesis (M.S. - Renewable Natural Resources)--University of Arizona. / Includes bibliographical references.

Thesis (M.S. - Agricultural Economics)--University of Arizona, 1985. / Includes bibliographical references (leaves 95-97).