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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Piezo-electric activity of Rochelle salt under various conditions

Valasek, Joseph, January 1900 (has links)
Thesis (Ph. D.)--University of Minnesota, 1921. / "Reprinted from Physical review, vol. XIX, no. 5, May, 1922."
112

Flow dynamics in salt marsh channels

Hannion, Muriel. Fagherazzi, Sergio. January 2006 (has links)
Thesis (M. S.)--Florida State University, 2006. / Advisor: Sergio Fagherazzi, Florida State University, College of Arts and Sciences, Dept. of Geology. Title and description from dissertation home page (viewed June 12, 2006). Document formatted into pages; contains ix, 83 pages. Includes bibliographical references.
113

Evidence for manganese-catalyzed nitrogen cycling in salt marsh sediments

Newton, Jennifer Denise. January 2006 (has links)
Thesis (M. S.)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2006. / Taillefert, Martial, Committee Chair ; Ingall, Ellery, Committee Member ; DiChristina, Thomas, Committee Member.
114

Salt tectonics and sequence-stratigraphic history of minibasins near the Sigsbee Escarpment, Gulf of Mexico

Montoya, Patricia. January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
115

Electrical and magnetic characterisation of a series of TCNQ salts

Cross, Graham Hugh January 1985 (has links)
The electrical and magnetic properties of a series of 12 isostructural TCNQ salts of bis-pyridinium cations are reported and these properties are related to the structural characteristics. The role of the cation lattice in stabilising a regular TCNQ stack in these salts is discussed. For comparison with this series, the electrical and magnetic properties of two TCNQ salts of bis-pyridinium cations with ordered structures and two salts of dialkyldiphenylphosphonium cations are reported. Within the isostructural series of salts, the stoichiometry takes values of between 1:3 and 1:5, and the cation length determines the stoichiometry. In all these salts, the hydrated cation lattice is disordered and the TCNQs stack in regular columns. The room temperature conductivities, measured along the stacking axis, are in the range 0.05 to 500 S/cm with the highest conductivities observed in dehydrated salts having the approximate stoichiometry, 1:4.5. The 1:5 salts possess the lowest conductivity of the series and in these salts the cation lattice is partially ordered. The 1:3 and 1:4 salts are small band gap semi-conductors whereas the conductivity of the 1:5 salts is not simply activated within the experimental range of temperatures. In these salts the conductivity obeys the empirical power law: [mathematical equation]. The temperature dependence of the magnetic susceptibility of all but the 1:3 salts of the isostructural series is characteristic of a system of partially localised triplet excitons. The magnitude of the singlet-triplet exchange energy exhibits a stoichiometric dependence and is lower in the 1:5 salts where the spin concentration is lower. The magnetic susceptibility of the 1:3 salts varies with temperature according to the Curie-Weiss law. The apparent low spin concentration supports the evidence found for alloy formation in these salts where the cation lattice is partially occupied by neutral or monoquaternised base.
116

A retrospective chart review of the guiding symptoms of the successful prescription of Natrum muriaticum at a homoeopathic satellite clinic

Sibeko, Nompumelelo Marcia January 2018 (has links)
Submitted in partial compliance with the requirements of the Master’s Degree in Technology: Homoeopathy, Durban University of Technology, Durban, South Africa, 2018. / Brief background In the practice of Homoeopathy, widely acting remedies or polychrest homoeopathic medicines are prescribed in the treatment of a wide range of clinical conditions. The documenting of the guiding symptoms in successfully treated cases will assist in offering guidelines for the prescription of remedies in the future and thus serves as scientific and clinical verification of the remedies. The operational definition of success for the purposes of clinical verification is the alleviation or improvement of existing symptoms (Van Wassenhoven 2013). This definition was applied in the context of this study. To facilitate high standards of health care as well as teaching and learning, Durban University of Technology (DUT) Department of Homoeopathy in collaboration with Lifeline established its first Homoeopathic Community Clinic in 2004 called Ukuba Nesibindi Homoeopathic Community Clinic (UNHCC) located in Warwick Junction, Durban. UNHCC provides a free Homoeopathic primary health care service on the third floor of the Lifeline building in Acorn Road, Warwick Triangle, less than one kilometre from the main DUT campus The area is classified as being disadvantaged with high crime rates, prostitution, violence, small informal businesses and low cost housing (Smillie 2010, Watson 2015 and Dube 2015). Aim of the study The study aimed to determine and compare the guiding symptoms of the successful prescription of Natrum muriaticum at Ukuba Nesibindi Homoeopathic Community Clinic (UNHCC) between 2013 and 2016. Methodology A retrospective chart review was conducted at the Ukuba Nesibindi Homoeopathic Community Clinic on the patient files between 2013 and 2016. A rubric (Appendix B) was used to document the demographics, clinical conditions, homoeopathic guiding symptoms, posology and follow up presentation of each chart where Natrum muriaticum was successfully prescribed. Furthermore, a comparison of the guiding prescribing symptoms was made against existing materia medica. A sample size of 197 patient files which had appropriate consent forms enclosed allowing for the use of information for research purposes was established. Prior to gathering the relevant information and the commencement of the study, gate keeper permission to conduct the study on patient files and at the mentioned location was requested and granted by all relevant stakeholders. The actual sample size was derived from the successful cases with follow ups until data saturation. Files that were excluded from the 197 patient files were of those patients who did not attend the follow up appointment and cases which were not treated successfully with the remedy. The sample size for the study was 37. Descriptive statistics was derived and illustrated using bar graphs and pie charts. Tabulations and graphical presentation of the comparison were created. Themes and inferences were drawn based on the emerged data from the symptoms and rubrics. Thereafter, a comparison to the existing materia medica was conducted by comparing the arising symptomatology with the existing content in the materia medica. Results The results of the study showed that the symptoms that arise in the study corresponded with the symptoms in the existing materia medica, however there were additional symptoms that emerged in the study and these symptoms were not listed in the materia medica, but were successfully treated with Natrum muriaticum. It was concluded that the guiding symptoms that were considered in formulating the prescriptions of Natrum muriaticum correlate with the characteristic symptoms of Natrum muriaticum in the materia medicas by Vermeulen, Boericke and Phatak / M
117

The uses, sources and production of salt in Wales : with particular reference to the Swansea and Gower areas

White, Albert E. S. January 1996 (has links)
No description available.
118

The role of salt tectonics in the hydrocarbon potential of the post-salt deposits (albian to recent), offshore Gabon

Makhubele, Marvel M.H. January 2014 (has links)
Masters of Science / Following successful discovery and production of hydrocarbons, Gabon is one of the key hydrocarbon target countries in Africa. Located in the Lower Congo Basin, the study area is based in Etame Marin Permit (EMP), which is licensed to VAALCO Energy Inc., and has been producing hydrocarbons since 2002. The currently explored and producing reservoirs are in the pre-salt sandstones of the Aptian Gamba Formation, charged with hydrocarbons sourced from the syn-rift lacustrine shale of the pre-Aptian Melania Formation. With the aim of finding potential petroleum plays in the post-salt successions and by using 3D prestack depth migration (PSDM) seismic sections and wireline logs, a detailed study of the post- Aptian stratigraphy and salt tectonics of the EMP was undertaken. Eight distinct reflectors were identified based on gamma ray signatures, stratal terminations and isopach trends. Sediment distribution patterns and the relative sea level history of the succession were determined by applying principles of sequence stratigraphy and salt tectonics. Furthermore, two potential plays have been outlined in the post-salt carbonates of the Albian Madiela Formation as well as in sandstones of the Turonian Azile Formation. These reservoirs might have been charged with hydrocarbons from the pre-salt shale of the Melania Formation and/or potentially also enriched from the Albian and Cenomanian shales. For these post-salt hydrocarbon reservoirs to be charged by the pre-salt source rocks, windows within the extensive evaporitic sealing of the Aptian Ezanga Formation were required. 3D PSDM seismic sections attest that diapirism of the Aptian salt unit generated ample hydrocarbon migration pathways from the pre-salt source rocks to post-salt reservoirs. Five well-developed potential salt windows have been identified, two of which have good probability to have facilitated the upward migration of hydrocarbons, because these salt windows are located up dip of oil producing wells. However, even if hydrocarbons are found in the post-salt reservoirs, similarly to the Yombo Field (located offshore Congo, south of the EMP), these shallow reservoirs in the EMP are likely to produce heavy oils due to biodegradation.
119

Effect of salt concentration and cation valence on maximum yield of a bentonite claypaste

Hu, Chien-Sheng January 1972 (has links)
A review is given on the factors important to the build-up of a gel structure in clay suspensions. The effect of salt is especially stressed. The maximum yield stress of a 19.06 weight per cent washed Bentonite clay paste was measured with a Rotovisco viscometer as a function of the concentration of five salts which were added individually to the paste. The salt concentration was varied from .002 molality up to the coagulation concentration. Two groups of salts were studied; those which had cations in common with the caly: NaCl and CaCl₂, and those found only in trace amounts in clay: CuCl, MnCl₂ and CeCl₃. The behavior of the two groups of salt was quite different. The latter group produced a maximum developable yield value in the clay which was inversely proportional to the valence of the cation. Sodium Chloride produced the largest maximum yield value at a high salt concentration while no yield value could be found for clay with concentrations of CaCl₂ above 0.002M. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
120

A theoretical and experimental examination of sodium chloride hydration

Modra, Debra Conway 01 January 1984 (has links)
A Hitachi Hu 125C transmission electron microscope in which the standard specimen holder was replaced by an environmental cell was used to observe the hydration of sodium chloride crystals. To observe Kelvin curvature and solubility effects sodium chloride crystals which were 0.1u or smaller were of special interest. An electrohome video system attached to the electron microscope was used to record the sodium chloride hydration for subsequent particle measurement and viewing. A theoretical model was also developed. Thermodynamic properties such as the Kelvin curvature and solubility effects were considered as well as the kinetic expressions for salt dissolution/recrystalization and water evaporation/condensation. A computer program for use on a Honeywell computer was written to perform the required calculations. The theoretical model was also used in attempts to explain the observed phenomenon of crystal shattering.

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