Thesis (Ph. D.)--University of Chicago, 1913. / Reprinted from the Journal of infectious diseases, vol. II, no. 3 November, 1912; vol. XIII, no. 3, November, 1913; vol. 16, no. 3, May, 1915. Includes bibliographical references (p. 422-424) Also available on the Internet.

Universiẗat, Diss., 2001--Stuttgart. / Gedr. Ausg. im Max-Planck-Inst. für Metallforschung, Stuttgart.

Brandenburgische Techn. Universiẗat, Diss., 2004--Cottbus.

Thesis (M.S.)--Northern Michigan University, 2007. / Includes bibliographical references (leaves 82-83).

No description available.

No description available.

The oxidation characteristics of iron droplets and a range of binary iron alloy droplets have been investigated at 1600°C. The droplets were generated by a novel technique of melting the iron or iron-alloy, in the form of wire, in a levitation coil. The droplets were held for several minutes in hydrogen prior to releasing them into a mass transfer column separated from the levitation chamber by a thin plastic film. The oxidised droplets were quenched. The oxidising or reducing characteristics of various quenching media were investigated and silicone oil was selected as the quenchant. Pure iron and a range of iron-manganese, iron-chromium and iron-silicon alloys were investigated. Whereas the iron-manganese system showed increasing oxygen pick-up with increasing manganese content, the iron-chromium and iron-silicon systems showed an inversion in oxidation behaviour after an initial increase in oxidation rate. The oxidation characteristics of these systems have been related to the surface morphology of the droplets as revealed by Scanning Electron Microscopy and to SIMS analysis of the thin surface oxide films, and mechanisms are proposed for each system. A mathematical model has been developed which simulates the mass transfer of oxygen by forced convection to an accelerating molten iron droplet. The model generates an almost linear oxidation rate for iron, for the period of flight of the droplet and is in good agreement with the experimental work when the model is compensated for circulation within the droplet. The model predicts that temperature has a minimal effect on oxidation rate whereas droplet size is of major importance. Both of these effects were confirmed by the experimental studies. The roles of the alloying elements in relation to the characteristics of oxide films reduced in hydrogen at 1150°C have also been considered. Reduction mechanisms are postulated to account for the morphology of the reduced droplets and the final oxygen levels in the droplets.

Mantle xenoliths have been used to interpret the magnetic characteristics of the lithospheric mantle because their rapid rate of ascent to the surface does not allow enough time for alteration. Studies of mantle xenoliths have suggested that magnetite in the mantle contributes to long wave length magnetic anomalies over areas of suppressed geothermal gradients (cratons, forearcs). Magnetite will only form in oxidizing conditions. This leads to a debate if mantle xenoliths become altered through oxidation to form magnetite in the mantle before ascent, during ascent (decompression), or after ascent at the surface. Natural and experimental occurrences of magnetite forming as inclusions or dislocations in fosterite from Fe-impurities suggest that oxidation of olivine is a mechanism for magnetite formation in the mantle. To test this, high olivine samples were placed into a furnace at 600C and 900C in free air at 1bar of pressure, removing samples at different time increments ranging from 0.2 to 625 hours. These temperatures were used because they represent mantle like temperatures in oxidizing conditions. After oxidation, samples from the 900C experiment show evidence for magnetite/hematite formation after only 0.2 hours and the amount of Fe-oxide formation increases with time. Samples from the 600C experiment show significant alteration and Fe-oxide formation after 125 hours. These results suggest that it is possible for magnetite to form from the Fe in the fayalite component of fosterite in the mantle from oxidizing event such as metasomatism.

In this research work, we have investigated the band engineering of epitaxial graphene using first principles calculations. Epitaxial graphene on SiC (0001) surface is modified by using different methods such as intercalation, doping, passivation and oxidation. The calculations are done using Density functional theory which is implemented in quantum espresso package. In the presence of H intercalation, epitaxial graphene is shown to have p type behavior with monolayer graphene. However this behavior is different for multilayer epitaxial graphene systems, and it depended on the concentration of the H atoms. When epitaxial graphene is intercalated with Ge atoms, the Ge atoms make clusters and these clusters are responsible for the electronic properties of the epitaxial graphene systems. As a result of oxidation of epitaxial SiC surface, the graphene layer is mostly stable on the surface for both silicates and oxynitrides structures. For silicate/SiC configurations, the epitaxial graphene is shown to be less n type. For oxynitrides/ SiC configurations, epitaxial graphene is shown to be neutral. In the presence of oxygen intercalation with silicate/SiC, epitaxial graphene is shown to have p type behavior. These systematic studies of epitaxial graphene will opens up great potential for electronic applications. Additionally the resultant models can be used to guide further studies.

Made available in DSpace on 2014-06-11T19:32:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2001Bitstream added on 2014-06-13T19:42:37Z : No. of bitstreams: 1 hokama_nk_dr_botfm.pdf: 442709 bytes, checksum: 19c729c7bb99de9b488b0c496f8b3922 (MD5) / A hemoglobina, o componente principal do citoplasma eritrocitário, está sujeita à oxidação, fisiologicamente ou por agentes externos, seja através da formação de Metahemoglobina, ou pela oxidação da cisteína β93 por agentes tiois. Impossibilitado de sintetizar proteína, o eritrócito depende primordialmente da via glicolítica, que, além de fornecer ATP, através da integração da formação de NADH e da Via da Hexose Monofosfato, mantém o potencial redutor extremamente eficiente. A presente investigação teve como finalidade avaliar o sistema de óxido-redução eritrocitário, à partir da oxidação da hemoglobina pelas seguintes drogas: a) Nitrito de Sódio, indutora da formação de Metahemoglobina; b) Azul de Metileno, utilizado terapeuticamente e em testes laboratoriais na redução de Metahemoglobina; c) Cistamina, agente tiol, que induz à formação do complexo Hemoglobina-Etilamina, através da oxidação da cisteína β93. Doadores de sangue da Divisão Hemocentro foram convidados a participar do trabalho e tiverem seu sangue coletado após consentimento - 96 - verbal e por escrito. Todos os indivíduos eram do sexo masculino, não anêmicos e sem deficiência de G6PD. Foram utilizados, para os testes, glóbulos lavados, ressuspensos em PBS, pH 7.45, com hemoglobina ajustada entre 11 e 13 g/dl, na presença de glicose e incubados a 37o C com as drogas testadas, nos momentos 10. 90 e 180 minutos de incubação... / Hemoglobin, the essential component of erythrocyte cytoplasm, is physiologically prone to oxidation by external agents, through the formation of Methemoglobin or the oxidation of β93 cysteine by thiol agents. Unable to protein synthesis, the erythrocyte depends essentially on glycolysis, which, besides producing ATP, maintains the highly efficient reduction potential through the integration of NADH production and the Hexose Monophosphate Shunt. The present investigation’s purpose was to evaluate the erythrocyte antioxidant system by studying hemoglobin oxidation by the following substances: a) Sodium Nitrite (SN), a well known Methemoglobin-forming agent; b) Methylene Blue (MB), a Methemoglobin reductant reagent, available for therapeutic and laboratory tests; c) the thiol reagent Cystamine (CI), that reacts with hemoglobin through the β93 cysteine oxidation, forming the Hemoglobin-Ethylamine complex. After informed... (Complete abstract click electronic access below)