No description available.

In this thesis an attempt has been made to try to dissect out the relative importance of atrial natriuretic peptides (ANP) and the renin-angiotensin-aldosterone system in the control of sodium balance in normal man. At the same time the thesis examines the relevance of ANP in the pathophysiology of essential hypertension and cardiac transplantation and the potential therapeutic value of manipulating the ANP system. The studies described in this thesis were important in suggesting a dominant role of suppression of the renin-angiotensin-aldosterone system in permitting excretion of short term increases in intravenous or oral sodium intake. The permissive effects of suppression of angiotensin II or aldosterone for the excretion of an intravenous sodium load showed clear time differences, with suppression of angiotensin II important immediately but the response to suppression of aldosterone delayed. In contrast, there appears to be only a transient role for changes in circulating levels of ANP in the response to an intravenous sodium load and little evidence that changes in ANP release are important in responding to acute increases in dietary sodium intake in normal subjects. However, the sensing mechanism for ANP release is clearly activated by sustained changes in dietary sodium intake. Studies of prolonged dietary sodium alteration in normal subjects clear evidence for a role of ANP in the medium term regulation of sodium balance and further dietary studies suggested an important role for the ANP system in pathophysiology in essential hypertension and in cardiac transplant recipients.

This thesis studies the effects of Na diffusion in Cu(In,Ga)Se2 (CIGS) solar cells,caused by electrical Potential Induced Degradation (PID) and how to prevent it. Thiswas done by subjecting CIGS solar cells a temperature of 850C and an electrical biasfrom the backside of the glass substrate to the Mo back contact of the CIGS cell.When the bias was negative at the back contact the Na diffused in to the CIGS(degradation) and when it was positive the ions diffused out again (recovery). TheCIGS samples were electrically characterized with IV- and EQE-measurements duringthese conditions and compositional depth profiling was used to track the Nadistribution.This study showed that during degradation Na seemed to accumulate in the interfacesbetween the different layers in the CIGS cell. The buffer and window layers arestrongly affected by Na diffusion. Zn(O,S) buffer layer showed a clear difference inrecovery behavior compared to CdS buffer layer. The introduction of an Al2O3barrier layer between the CIGS and Mo back contact increased the degradation timefrom 50 h to 160 h. During this study it was also found that in some cases the CIGSsolar cells efficiency could be improved by degrading the cells and then recoveringthem, in the best case from 13% average energy efficiency to 15% efficiency.

No description available.

Typescript. / Thesis (Ph. D.)--University of Hawaii, 1965. / Bibliography: leaves [68]-71. / vi, 71 l illus., tables

The effects of sodium bisulphate on the xanthate-induced flotation of chalcopyrite, copper-activated sphalerite and copper-activated pyrite have been studied. These investigations were conducted in two steps: 1) single mineral studies with varying experimental conditions; and 2) a mixed mineral chalcopyrite-pyrite-sphalerite study. A number of solution and surface spectroscopic techniques were used, which allowed simultaneous investigation of the mechanisms of interaction of sulphite ions with the mineral surfaces, and with the xanthate species in solution and its adsorbed state. Based on the results obtained, the following depressing mechanisms have been proposed. / It was found that sulphite ions had no depressing effect on chalcopyrite flotation under the experimental conditions studied. It was suggested that the main species responsible for chalcopyrite floatation were the hydrophobic sulphur-like species, such as an iron deficient chalcopyrite and polysulphide, and to some extent the adsorbed collector species. Sodium bisulphite did not decompose these hydrophobic phases on the chalcopyrite surface. It was also found that the chalcopyrite surface was not heavily oxidised either in the presence or absence of sulphite ions. / From the single mineral studies it was concluded that sodium bisulphite had a complex effect on the xanthate-induced floatation of copper-activated pyrite and sphalerite. These results demonstrated that under the experimental conditions tested, the following processes contribute to the selective depression of pyrite and sphalerite: (i) Xanthate decomposition in solution by sulphite ions, hence reducing the xanthate adsorption on the mineral surfaces. (ii) Collector removal from the mineral particles, rendering the mineral surfaces more hydrophilic. (iii) Sulphite oxidation to sulphate, accompanied by consumption of dissolved oxygen in solution, thus limiting collector adsorption (accompanied by a drop of pulp redox potential). (iv) Decomposition of hydrophobic sulphur-like species on the sphalerite and pyrite surfaces, rendering the mineral particles less floatable. (v) Surface oxidation of pyrite and sphalerite particles to produce hydroxide and oxy species, also rendering the mineral surfaces hydrophilic and preventing collector adsorption. As expected, these effects were more pronounced in the floatation experiments with air purging. / The mixed mineral study demonstrated that sodium bisulphate acted as an effective depressant for pyrite and sphalerite in the mineral mixture, while the chalcopyrite floatability was almost un-affected by sulphite ions. It was found that the mechanisms proposed for single mineral systems could satisfactorily explain the effect of sodium bisulphite on the floatation results obtained with the chalcopyrite-sphalerite-pyrite mineral mixture. Chalcopyrite floatation was not depressed by sulphite, due to the high stability of adsorbed xanthate species, and also due to the natural floatability of the chalcopyrite particles. At the same time, a reduction in the adsorbed collector concentration and a commensurate increase in surface hydrophilicity were responsible for the depression of pyrite and sphalerite from the mineral mixture in the presence of sulphite ions. / Thesis (PhDAppliedEngineering)--University of South Australia, 2003.

v, 142 leaves : ill., appendices / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physics, 1973

"May 1958." / Includes bibliographical references (leaves 162-167). / Includes reprint of article co-authored by the author at back: Sodium as an essential micro-nutrient element for Atriplex vesicaria, Heward / P.F. Brownell, J.G. Good. Reprinted from Nature, vol. 179, pp. 635-636, March 23, 1957 / iv, 167 leaves : ill. ; 27 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Botany, 1958

Thesis (Ph.D) -- University of Adelaide, Dept. of Physics, 1973.

Thesis (Ph.D.)--University of Delaware, 2008. / Principal faculty advisor: Robert A. Sikes, Dept. of Biological Sciences. Includes bibliographical references.