Дисертації: "Surface physic"

1

SAVINO, UMBERTO. "Physical properties of metal-oxide surfaces for CO2 valorisation." Doctoral thesis, Politecnico di Torino, 2020. http://hdl.handle.net/11583/2823956.

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2

Zhang, Yancheng. "Numerical simulation approaches and methodologies for multi-physic comprehensions of titanium alloy (Ti-6Al-4V) CUTTING." Phd thesis, INSA de Lyon, 2011. http://tel.archives-ouvertes.fr/tel-00708761.

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The objective of this study is to model material removal with cutting tool in the case of the machining of Titanium alloy (Ti-6Al-4V) and to bring a multi-physic comprehension of chip formation and the tool/workpiece interaction by adopting finite element approaches and methodologies. For that, the present contribution begins by a macroscopic modeling of the orthogonal cutting process. The cut material behavior considered is supposed based on JC law. Moreover, in order to simulate properly the chip genesis, the material fracture energy concept is adopted for controlling the material damage evolution. This allows capturing the shear strain localization and consequently the chip segmentation for a given set of cutting parameters. The frictional contact model considers the influence of temperature on the limiting shear stress at the tool/chip interface. As a result, this reliable model has the capability to simulate the cutting process even with high coefficient of friction and with large cutting edge radius. The parametric study carried out by referring to this model shows a very interesting corroboration with experimental results. In a second step, the present research work presents a material microstructure-level cutting model (MML cutting model) for cutting simulation. The crystal plasticity theory is adopted for modeling the cutting of the Titanium alloy Ti-6Al-4V in orthogonal case. In this model, the grains of the studied material are explicitly considered, and their orientation angles and slip system strength anisotropy are considered as the main source of the microstructure heterogeneity in the cutting material. To simulate the material degradation process, the continuum intra-granular damage and discrete cohesive zone inter-granular damage models are developed, wherein the zero thickness cohesive elements are implemented to simulate the bond between grain interfaces. The material model is validated by a comparison of compression tests from literature. Finally, simulation results demonstrate the possibility to capture the influence of the microstructure on the material removal in terms of chip formation. It is demonstrated that the grain orientation angle plays an important role for the chip segmentation and its periodicity during the cutting process. This certainly can affect the evolution of the cutting force. Additionally, the surface integrity is discussed based on the MML cutting model for different cutting speeds and feed rates. Indeed, a parametric study shows that the surface integrity is seriously affected by the machining parameters, and the affected region is limited within three layer grains for the present MML cutting model.

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3

Mansfield, Mark. "Surface stress and reconstructions on metal surfaces." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359866.

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4

Pinheiro, Analia Maria. "Desenvolvimento de nÃctares mistos Ã base de caju (Anacardium occidentale L) e aÃaÃ (Euterpe oleracea Mart.)." Universidade Federal do CearÃ, 2008. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2114.

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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
O setor que vem crescendo nos Ãltimos anos Ã o de bebidas. Em todos os paÃses os levantamentos estatÃsticos revelam nÃmeros crescentes de consumo, tanto per capita quanto global. Esses valores sÃo mais expressivos quando se refere a bebidas obtidas de frutas, pelo fato das mesmas se constituÃrem fontes importantes de vitaminas e minerais para a dieta humana, alÃm de seus atrativos sabores. O Norte e Nordeste do Brasil, por exemplo, sÃo regiÃes privilegiadas neste particular. Portanto, pode-se dizer que Ã ainda muito inibida, a iniciativa de desenvolver formas de exploraÃÃo desses potenciais, com o objetivo de desenvolver nÃctares. Este estudo teve como objetivo desenvolver um nÃctar misto a base de suco integral de caju e polpa de aÃaÃ. Foi realizado atravÃs de um planejamento experimental composto central 22, onde as variÃveis foram percentuais de polpa de aÃaÃ (20 a 80%), percentual de suco de caju integral (20 a 80%) e percentual de polpa total (30 a 60%). O teor de sÃlidos solÃveis totais foi fixado em 11ÂBrix. As onze formulaÃÃes foram submetidas a testes sensoriais de impressÃo global, aparÃncia, sabor e intenÃÃo de compra, realizadas com 70 provadores nÃo treinados. A melhor formulaÃÃo selecionada atravÃs das respostas dadas pelos provadores, com auxilio da ferramenta estatÃstica de anÃlise de superfÃcie de resposta, foi aquela com 30,0% do teor de polpa total, sendo, 54,2% de polpa de aÃaÃ, e 45,8% de suco de caju integral. O nÃctar elaborado foi envasado em embalagens de vidro e PET. O nÃctar final selecionado foi submetido Ãs anÃlises quÃmicas, fÃsico-quÃmicas, microbiolÃgicas e sensoriais. Os resultados para as anÃlises quÃmicas e fÃsico-quÃmicas nÃo apresentaram interaÃÃo significativa (p>0,05) entre embalagens e tempo de armazenamento exceto para os aÃÃcares totais que apresentaram interaÃÃo significativa (p≤0,05). Os resultados microbiolÃgicos foram satisfatÃrios para coliformes (35ÂC e 45ÂC) e salmonella sp. Para os resultados sensoriais, realizados com 100 provadores nÃo treinados, nÃo ocorreram alteraÃÃes significativas ao nÃvel de 5% de probabilidade, entre as embalagens (PET e vidro) e os tempos (zero e trinta dias), nos parÃmetros de aparÃncia, sabor, impressÃo global e intenÃÃo de compra.
The sector of beverages is increasing in recent years. In the majority of countries the statistical data show increasing consumption per capita and global. These values are more expressive when are related to beverage obtained from fruits, due to the fact that they constitute important source of vitamins and minerals for the human diet besides as possessing flavors. The northeast and north regions of Brazil occupy important place due large cultivation of the fruits particularly tropical and sub-tropical fruits. Therefore it can be said still there is very little initiative for exploration of this potential including the obtaining of nectars. This study had the purpose to develop mixed nectar based on cashew apple juice and acai pulp, through an experimental model of 22 where the variables were percentage of aÃaÃ pulp (20 to 80%) and percentage of cashew juice (20 to 80 %) and total pulp percentage (30 to 60%). The amount of total soluble solids contents was fixed at 11ÂBrix. The eleven formulations were submitted to sensorial analysis of global impression, appearance, flavor and buying intention, performed by 70 non trained panelists. The best formulation selected through the responses given by the panelists, with the help of statistical analysis of surface response methodology was that 30% of total pulp content, being 54.2% aÃaÃ pulp and 45.8% cashew apple juice. The nectars were packed in glass and PET bottles. The results of chemical and physicochemical analysis donât presented significant interaction (p > 0.05) between packaging and storage time, except for the total sugars that presented significant interaction (p < 0.05). The microbiological results were satisfactory for coliforms (35 Â C and 45 Â C) and Salmonella sp. There were no significant interaction (p > 0.05) between packaging (PET and glass) and storage time (zero and 30 days) to the sensory attributes of appearance, taste and overall impression and to intention to purchase.

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5

Pinheiro, Analia Maria. "Desenvolvimento de néctares mistos à base de caju (Anacardium occidentale L) e açaí (Euterpe oleracea Mart.)." reponame:Repositório Institucional da UFC, 2008. http://www.repositorio.ufc.br/handle/riufc/17223.

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PINHEIRO, Analia Maria. Desenvolvimento de néctares mistos à base de caju (Anacardium occidentale L) e açaí (Euterpe oleracea Mart.). 2008. 75 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Tecnologia de Alimentos, Fortaleza-CE, 2008
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The sector of beverages is increasing in recent years. In the majority of countries the statistical data show increasing consumption per capita and global. These values are more expressive when are related to beverage obtained from fruits, due to the fact that they constitute important source of vitamins and minerals for the human diet besides as possessing flavors. The northeast and north regions of Brazil occupy important place due large cultivation of the fruits particularly tropical and sub-tropical fruits. Therefore it can be said still there is very little initiative for exploration of this potential including the obtaining of nectars. This study had the purpose to develop mixed nectar based on cashew apple juice and acai pulp, through an experimental model of 22 where the variables were percentage of açaí pulp (20 to 80%) and percentage of cashew juice (20 to 80 %) and total pulp percentage (30 to 60%). The amount of total soluble solids contents was fixed at 11ºBrix. The eleven formulations were submitted to sensorial analysis of global impression, appearance, flavor and buying intention, performed by 70 non trained panelists. The best formulation selected through the responses given by the panelists, with the help of statistical analysis of surface response methodology was that 30% of total pulp content, being 54.2% açaí pulp and 45.8% cashew apple juice. The nectars were packed in glass and PET bottles. The results of chemical and physicochemical analysis don’t presented significant interaction (p > 0.05) between packaging and storage time, except for the total sugars that presented significant interaction (p < 0.05). The microbiological results were satisfactory for coliforms (35 ° C and 45 ° C) and Salmonella sp. There were no significant interaction (p > 0.05) between packaging (PET and glass) and storage time (zero and 30 days) to the sensory attributes of appearance, taste and overall impression and to intention to purchase.
O setor que vem crescendo nos últimos anos é o de bebidas. Em todos os países os levantamentos estatísticos revelam números crescentes de consumo, tanto per capita quanto global. Esses valores são mais expressivos quando se refere a bebidas obtidas de frutas, pelo fato das mesmas se constituírem fontes importantes de vitaminas e minerais para a dieta humana, além de seus atrativos sabores. O Norte e Nordeste do Brasil, por exemplo, são regiões privilegiadas neste particular. Portanto, pode-se dizer que é ainda muito inibida, a iniciativa de desenvolver formas de exploração desses potenciais, com o objetivo de desenvolver néctares. Este estudo teve como objetivo desenvolver um néctar misto a base de suco integral de caju e polpa de açaí. Foi realizado através de um planejamento experimental composto central 22, onde as variáveis foram percentuais de polpa de açaí (20 a 80%), percentual de suco de caju integral (20 a 80%) e percentual de polpa total (30 a 60%). O teor de sólidos solúveis totais foi fixado em 11ºBrix. As onze formulações foram submetidas a testes sensoriais de impressão global, aparência, sabor e intenção de compra, realizadas com 70 provadores não treinados. A melhor formulação selecionada através das respostas dadas pelos provadores, com auxilio da ferramenta estatística de análise de superfície de resposta, foi aquela com 30,0% do teor de polpa total, sendo, 54,2% de polpa de açaí, e 45,8% de suco de caju integral. O néctar elaborado foi envasado em embalagens de vidro e PET. O néctar final selecionado foi submetido às análises químicas, físico-químicas, microbiológicas e sensoriais. Os resultados para as análises químicas e físico-químicas não apresentaram interação significativa (p>0,05) entre embalagens e tempo de armazenamento exceto para os açúcares totais que apresentaram interação significativa (p≤0,05). Os resultados microbiológicos foram satisfatórios para coliformes (35ºC e 45ºC) e salmonella sp. Para os resultados sensoriais, realizados com 100 provadores não treinados, não ocorreram alterações significativas ao nível de 5% de probabilidade, entre as embalagens (PET e vidro) e os tempos (zero e trinta dias), nos parâmetros de aparência, sabor, impressão global e intenção de compra.

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6

Abbar, Bouamama. "Influence de la physico-chimie des eaux de ruissellement sur la vulnérabilité des ouvrages de rétention." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMLH04/document.

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Dans ce travail de thèse on a examiné expérimentalement l’efficacité épuratoire d’un dispositif de filtration, constitué de sable concassé et de nappes de géotextile en fibre de lin, à l’échelle de laboratoire afin d’installer en conditions locales (Agglomération Havraise) un site expérimental en vraie grandeur. Deux types d’essais ont été utilisés : (1) Des essais batch pour quantifier le potentiel de sorption des ions plomb, cuivre et zinc par les étoupes de fibres de lin à partir d'une solution aqueuse. (2) Des essais de filtration de longue durée dans des colonnes en laboratoire remplie de sable concassé avec et sans strates de géotextile en fibres de lin pour étudier l'influence de la présence de géotextiles sur le transfert et la rétention (i) des particules en suspension non polluées (particules de kaolinite) (ii) des métaux lourds solubles dans l'eau (iii) des métaux lourds sous forme particulaire (ions métalliques adsorbés sur les particules de kaolinite en suspension) et métaux lourds et solubles dans l'eau. Les essais de sorption ont montré que l'adsorption des ions métalliques par les fibres de lin est favorable avec une capacité d'adsorption maximale de 9,9 ; 10,7 et 8,4 mg g-1 respectivement pour le cuivre, le plomb et le zinc. Les essais de filtration ont montré que la présence des géotextiles dans le sable influence le transfert des métaux lourds, sous les deux formes soluble et particulaire. La rétention des métaux dans le sable est favorisée et les profils de rétention sont modifiés. De plus, et contrairement aux géotextiles synthétiques, les géotextiles en fibres de lin contribuent eux-mêmes à la rétention d’une fraction non négligeable de polluants métalliques sous forme soluble et particulaire dans leur propre structure. L’efficacité globale de rétention des métaux par le dispositif de filtration est améliorée. Ces résultats sont de bons indicateurs pour envisager l'utilisation de matériaux à base de fibre de lin dans la conception de systèmes de traitement local des eaux de ruissellement et l'élimination de polluants métalliques
In this thesis work, the purification efficiency of a filtration device, consisting of crushed sand and flax fiber geotextile layers, was investigated experimentally at the laboratory scale in order to install in local conditions (Havre agglomeration) an experimental site in full size. Two types of tests were used: (1) Batch tests to quantify the sorption potential of lead, copper and zinc ions by flax fiber tows from an aqueous solution , (2) Long-term filtration tests in laboratory columns filled with crushed sand with and without flax fiber geotextile layers to study the influence of the presence of geotextiles on the transfer and retention of (i) particles in unpolluted suspension (kaolinite particles) (ii) water-soluble heavy metals (iii) heavy metals in particulate form (metal ions adsorbed on suspended kaolinite particles) and heavy and water-soluble metals. Sorption tests have shown that the adsorption of metal ions by flax fibers is favorable with a maximum adsorption capacity of 9.9; 10.7 and 8.4 mg g-1 respectively for copper, lead and zinc. Filtration tests have shown that the presence of geotextiles in sand influences the transfer of heavy metals, in both soluble and particulate forms. The retention of metals in the sand is favored and the retention profiles are modified. In addition, and unlike synthetic geotextiles, flax fiber geotextiles themselves contribute to the retention of a significant fraction of metal pollutants in soluble and particulate form in their own structure. The overall metal retention efficiency of the filtration device is improved. These results are good indicators for considering the use of flax fiber materials in the design of local stormwater treatment systems and the removal of metal pollutants

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7

De, Zorzi Chiara <1976&gt. "Physico-chemical Characterization of Glass Surfaces: New Surface-related Analytical Approaches." Master's Degree Thesis, Università Ca' Foscari Venezia, 2021. http://hdl.handle.net/10579/20493.

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Since ancient times glass was used as storage material for ointments, medicinal remedies and cosmetics for its properties of inertness and product protection. Along the centuries the technology has developed dedicated glasses for pharmaceutical use, improving their mechanical and chemical performances up to the modern borosilicate glasses. Meanwhile the technology is trying to meet the needs of new complex and sensitive drugs, the necessity of new analytical approaches has increased for a better overview of the content-material interactions to complement the classical pharmacopoeia analysis. From this perspective a physico-chemical analytical approach, focused on the glass surface as main player of the drug-content interactions, is the main topic of this study. The application of surface dedicated complementary techniques as XPS, SIMS and SEM was investigated, permitting the characterization of the glass surface in terms of morphology, composition and depth elemental overview. As preliminary part of a more complex project, this study focused on the comparison and baseline characterization of the raw materials with the related finished containers, highlighting interesting surface features and glass composition-related peculiarities. This work confirms the suitability of these analytical techniques to pave the way for further studies on long term storage or environmental effects, helping to define a possible correlation with drug interactions phenomena.

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8

Ștefan, Gheorghiu. "Standard and nonstandard roughness - consequences for the physics of self-affine surfaces /." free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9988664.

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9

Leuty, Gary M. "Adsorption and Surface Structure Characteristics Toward Polymeric Bottle-Brush Surfaces via Multiscale Simulation." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1397577080.

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10

Shukla, Nisha. "Surface spectroscopic studies of coadsorbed molecules and surface reactions at single crystal metal surfaces." Thesis, Cardiff University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275212.

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11

Zheng, Chaozhi. "Coverage, step and quantum effects on surface diffusion of H on Pt(111) surfaces /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202004%20ZHENG.

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12

Bradley, Matthew K. "Density functional theory investigations of surface structure and surface stress in adsorbate layers on Cu, Pd and Ir surfaces." Thesis, University of Warwick, 2012. http://wrap.warwick.ac.uk/51619/.

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An introduction to surface structure and plane wave density functional theory (DFT) is presented along with theoretical studies of seven adsorbate systems. A new energetically favourable structure of low symmetry is found for furan on Pd(111) that is entirely consistent with previous experimental findings from scanned-energy mode photoelectron diffraction (PhD). In addition, it is found that the C3H3 decomposition product of furan on the same surface is likely to be adsorbed in a propargyle conformation (CH-C-CH2) although some cooccupation of the molecule in a half benzene conformation (CH-CH-CH) is also possible. Methoxy is found to adsorb at local short bridge sites only on Cu(110), occupying locations both above the clean surface and above pairs of surface Cu adatoms. Simulated scanning tunneling microscope (STM) images of the (5×2) reconstruction are found to be in qualitative agreement with previous images recorded experimentally. The experimentally determined local structure of cytosine on the same surface is confirmed and models are proposed for the (6×6) reconstruction. An increased tensile surface stress is found to be associated with the Ir(001)(1×1) ! Ir(001)(5×1)-hex phase transition, thus confirming that the reconstruction is not a consequence of the large surface stress of bulk terminated Ir(001). In contrast, H adsorption on Ir(001) (5×1)-hex does lead to a reduction of the surface stress in the range 1.76-2.06 Nm−1 for a H coverage range 0.6-0.8 ML in excellent agreement with the experimentally-determined value of 1.7 Nm−1. The energetically favourable structure for methanethiolate adsorption on Cu(100) is found to be a c(6×2) missing row structure that allows effective relief of surface stress. On Cu(111) several complex overlayer models for methanethiolate adsorption have similar associated surface energy, suggesting that the local structure is dependent on the availability of Cu adatoms. For adsorption on both surfaces, agreement with previous STM images and MEIS results is discussed.

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13

McLaughlin, Keith. "Toward understanding low surface friction on quasiperiodic surfaces." [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0003161.

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14

Bourrez, Marc. "Synthèse, étude et caractérisation de nouveaux catalyseurs moléculaires pour la réduction du CO2 en vue de son utilisation comme source de carbone." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENV048/document.

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Ce travail de thèse s'inscrit dans le contexte général des solutions envisageables pour répondre aux problèmes du réchauffement climatique global et de la diminution des ressources fossiles. Il a été en majeure partie consacré à l'étude et au développement d'électrocatalyseurs moléculaires pour la réduction du dioxyde de carbone. Un tel procédé pourrait permettre de transformer et valoriser le CO2 en l'exploitant comme une matière première carbonée disponible en quantité non limitée, bon marché et peu toxique. Dans une première partie, un métallocavitand, dont la structure est basée sur un calix[4]arène fonctionnalisé par quatre complexes phénanthroline tris-carbonyl de rhénium(I), a été étudié en solution et sur déposé sur surface transparente conductrice. Le but de cette étude était de contrôler par un stimulus électrochimique la fermeture et l'ouverture du bord large du cavitand. La complexité des processus rédox de ces métallo-macrocycles nous a conduits à étudier en détails les propriétés électrochimiques de complexes de rhénium(I) modèles. Ces propriétés avaient précédemment été rapportées dans la littérature mais étaient sujettes à désaccords entre les différents auteurs. Finalement l'ensemble de cette étude nous a conduits à préciser et à mieux comprendre le mécanisme de la catalyse de réduction du CO2 par ce type de complexes. Dans une deuxième partie, qui représente la partie la plus conséquente de cette thèse, la synthèse, la caractérisation physico-chimique et l'étude spectro-électrochimique de complexes bipyridine tris-carbonyle de manganèse, analogues des complexes de rhénium évoqués ci-dessus, ont été entreprises. Le but était de développer un catalyseur innovant pour la réduction électrochimique du dioxyde de carbone, du type complexe métallique, en substituant les métaux rares utilisés actuellement par un métal non-noble et abondant : le manganèse. Les propriétés électrochimiques des nouveaux complexes de Mn synthétisés ont été caractérisées en détail. La simulation des voltammétries cycliques, associée à des études mécanistiques par spectro-électrochimie UV-vis, a permis d'accéder aux données cinétiques et thermodynamiques des différentes réactions chimiques associées aux réactions de transferts d'électron irréversibles. Ces complexes de manganèse se sont révélés être des électrocatalyseurs de la réduction du CO2 au moins aussi efficaces que les complexes analogues de rhénium, décrits jusque-là comme étant les meilleurs systèmes pour cette application. Les complexes de Mn ainsi préparés montrent une excellente sélectivité (rendements faradiques élevés et peu ou pas de H2) et une bonne efficacité pour l'électro-réduction du CO2 en CO en milieu hydro-organique. Les catalyses à l'échelle préparatrice fonctionnent avec des surtensions modérées. Les mécanismes mis en jeu lors de la catalyse ont été étudiés par spectro-électrochimie UV-vis et RPE (en onde continue et pulsée) associées à des caculs théoriques DFT. Un intermédiaire-clé a ainsi pu être mis en évidence et caractérisé. Enfin, l'étude des réactions de décarbonylation photo-induites dans ces complexes est rapportée
This PhD takes place in the general context of possible solutions to global warming and peak oil issues. It mostly deals with the study and development of molecular electrocatalysts for carbon dioxide reduction. This process may open the way to the use and valorization of CO2 as a raw material. In the first part, a metallocavitand, which structure is based on a calix[4]arene modified by four phenanthroline tris-carbonyl rhenium(I) complexes, was studied in solution and deposited on a conductive transparent surface. The aim of this study was to control through an electrochemical stimulus the closing and opening of the wide rim of the cavitand. Complexity of the redox properties of the metallocavitand led us to investigate in detail the electrochemical properties of simpler examples of these rhenium(I) complexes. These properties were previously described in the literature ; however, there was disagreement in the interpretation of the results. Finally this study led us to a more precise and better understanding of the mechanism of the reduction of CO2 by a complex of this kind. In the second part, which is the main part of this PhD, synthesis, physico-chemical characterization and spectro-electrochemical study of bipyridine tris-carbonyl manganese complexes, analogues of the rhenium complexes mentioned above, were undertaken. The aim was to develop an innovative catalyst for the electrochemical reduction of carbon dioxide, based on a metallic complex, by substituting rare and noble metals currently used by a non-noble and abundant metal: manganese. Electrochemical properties of newly synthesized manganese complexes were investigated in detail. Simulations of cyclic voltammetry, associated with mechanism studies by UV-vis spectro-electrochemistry, allowed us to determine kinetic and thermodynamic properties of the different chemical reactions coupled with the irreversible electron transfers. These manganese complexes proved to electrocatalyse the reduction of carbon dioxide at least as efficiently as the analog rhenium complexes which were, until now, the best system for this application. These manganese electrocatalysts exhibit a very good selectivity (high faradic yields and no or very little H2) and a good efficiency for reduction of CO2 to CO in aqueous-organic media. Preparative scale electrolysis operates at low overpotential. Mechanisms of the different catalytic pathways were studied using UV-vis and EPR (continuous wave or pulsed) spectro-electrochemistry associated with DFT calculations. A key-intermediate was evinced and investigated. Finally the study of photo-induced decarbonylation reactions of these complexes is also described

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15

Dunn, Patrick. "Binary mixtures near surfaces." PDXScholar, 1992. https://pdxscholar.library.pdx.edu/open_access_etds/4216.

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This paper presents an approach to modeling a binary mixture near a surf ace. The approach used is based on statistical mechanics. The Cluster Variation (CV) method is used to solve an Ising-like model with a cluster size of two (neighboring lattice points). The free energy of the system is expressed in terms of the probabilities of occurrences of particular clusters. The CV method is first developed for a homogeneous system which leads to a set of three non-linear partial differential equations. The surface boundary is then introduced and the CV method is developed for this system which leads to a set of seven non-linear partial differential equations for each layer. In the calculations, the Natural Iteration (NI) method is introduced as a method of solving these non-linear partial differential equations. The steps involved in implementing the NI method are outlined. The number of layers is chosen to be 32. Concentration profiles are calculated for the binary system using the NI method and the results are discussed.

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16

Derby, Glyn Peter. "Surface core level shift studies of adsorbate covered tungsten single crystal surfaces." Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257131.

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17

Feng, Yongjia. "First principles studies of transition metal surfaces : the effect of an external field on surface electronic properties and surface energetics /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202003%20FENG.

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Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003.
Includes bibliographical references (leaves 106-110). Also available in electronic version. Access restricted to campus users.

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18

Hakim, Ali. "Characterization of Hard Metal Surfaces after Various Surface Process Treatments." Thesis, Linköping University, The Department of Physics, Chemistry and Biology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-12433.

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The aim of this thesis is to investigate how material surfaces are affected by various surface treatments and how this relates to the adhesion of the coating. The materials that were studied were WC-Co and Cermets and the surface treatments used were polishing, grinding with coarser and finer abrasive grains, and finally wet blasting and dry blasting. Focus was on deformations and residual stresses in the surface, surface roughness and cracks. The test methods used for examining the samples included surface roughness measurements, residual stress measurements, adhesion tests using Rockwell indentation and SEM images of the surface and the cross section.

The results concluded that polishing gives very good adhesion. Additionally, the adhesion for ground surfaces was good for WC-Co but very poor for Cermets. Furthermore, it was observed that finer abrasive grains did not result in better adhesion. In fact, the coarser grains gave slightly better results. Finally, it was concluded that wet blasting has a clear advantage over dry blasting and results in much better adhesion, especially for the Cermets. The results for the WC-Co were a bit inconsistent and so further research is required.

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19

Szabo, Tamas. "Energy transfer at gas-liquid interface towards energetic materials /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4797.

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Thesis (Ph. D.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on February 29, 2008) Vita. Includes bibliographical references.

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20

Toth, Réka. "Mécanismes physico-chimiques du polissage." Electronic Thesis or Diss., Paris 6, 2016. http://www.theses.fr/2016PA066763.

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Le polissage mécano-chimique (CMP pour Chemical Mechanical Polishing) consiste à appliquer une suspension colloïdale contenant des particules abrasives sur une surface solide (le substrat) au travers d’une pression exercée par un disque de polymère (le pad) en rotation. Un substrat de silice et des particules d’oxyde de cérium ont été choisis comme système de référence pour aider à la compréhension du mécanisme de polissage CMP. Des études macroscopiques ont été réalisées sur ce système afin d'étudier les effets de la concentration ou de la taille des particules abrasives, ainsi que l’influence du pH ou de la force ionique de la suspension de polissage. Le mécanisme a également été étudié à un niveau microscopique, en se concentrant sur les interactions entre le substrat et les particules abrasives. Cela a été effectué par une approche multi-instrumentale (zêtamétrie, ATR-FTIR, MET, SAXS, dosages chimiques, AFM). L’étude du polissage implique une bonne connaissance des surfaces en jeu, l'acido-basicité et l'oxydo-réduction des surfaces de CeO2 ont donc été étudiés. A partir de la compréhension acquise, des modifications des particules abrasives ont été réalisées (synthèse de particules cœur-coquilles et de solutions solides), et des particules de CeO2 de morphologies différentes testées
Chemical Mechanical Polishing (CMP) consists in applying a slurry of colloidal particles onto a solid surface called substrate, through a pressure applied with a rotating polymeric pad. A silica substrate and CeO2 particles were chosen as reference system to study the mechanism of CMP. Macroscopic studies have shown the effect of the concentration and the size of abrasive particles, as well as the importance of pH and ionic strength. The mechanism was more thoroughly studied by recirculating the slurry in fixed conditions. Surface interactions between the substrate and the particles were studied thanks to a multi-instrumental approach (zeta potential, ATR-FTIR, TEM, SAXS, chemical analysis, AFM).A good understanding of the surfaces at stake is necessary to study the mechanism of polishing. Acid-basic and redox properties of the CeO2 surface were therefore investigated. Finally, the surface chemistry of the abrasive particles were modified (synthesis of core-shell particles and solid solutions), and different ceria morphologies were tested

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21

Block, Stephan [Verfasser]. "On surface forces and morphology of linear polyelectrolytes physisorbed onto oppositely charged surfaces / Stephan Block." Greifswald : Universitätsbibliothek Greifswald, 2011. http://d-nb.info/1010396889/34.

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22

Lotfollahi, Ramin. "Electronic structure of surfaces." Thesis, Örebro University, Institutionen för naturvetenskap Department of Natural Sciences, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-640.

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For an idealized one-dimensional crystal it is possible to have energy levels whose wave functions are localized at the surface. These states are called surface states. There is one surface state for each energy gap between the ordinary allowed bands of energies. These electron states are called Tamm states. This Tamm state has an energy that lies almost at the middle of the energy gap and is mainly localized at the surface atomic layer. The image potential states are generated by a potential well formed by the Coulomb-like image potential barrier. These image states that are also called Shockley states are localized in a slowly decaying tail in the vacuum.

I also studied the lateral (in-plane) motion of electrons confined to terraces between steps on a vicinal Cu (111) surface. The local density of states showed a number of peaks at energies where electrons can occupy new quantum-well states on a step. I also tested the influence of the electron lifetime on the local density of states.

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23

Verma, Poonam Santosh. "Large Scale Computer Investigations of Non-Equilibrium Surface Growth for Surfaces From Parallel Discrete Event Simulations." MSSTATE, 2004. http://sun.library.msstate.edu/ETD-db/theses/available/etd-04192004-140532/.

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The asymptotic scaling properties of conservative algorithms for parallel discrete-event simulations (e.g.: for spatially distributed parallel simulations of dynamic Monte Carlo for spin systems) of one-dimensional systems with system size $L$ is studied. The particular case studied here is the case of one or two elements assigned to each processor element. The previously studied case of one element per processor is reviewed, and the two elements per processor case is presented. The key concept is a simulated time horizon which is an evolving non equilibrium surface, specific for the particular algorithm. It is shown that the flat-substrate initial condition is responsible for the existence of an initial non-scaling regime. Various methods to deal with this non-scaling regime are documented, both the final successful method and unsuccessful attempts. The width of this time horizon relates to desynchronization in the system of processors. Universal properties of the conservative time horizon are derived by constructing a distribution of the interface width at saturation.

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24

Fabre, Héloïse. "Contributions des propriétés physico-chimiques de surfaces de titane sur l'adhérence de microorganismes : application aux chambres implantables." Thesis, Le Mans, 2017. http://www.theses.fr/2017LEMA1023/document.

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Les chambres implantables sont des dispositifs médicaux utilisés pour l’'administration de produits de chimiothérapie et/ou de nutrition parentérale. Comme la plupart des implants médicaux, ces dispositifs peuvent être à l’'origine d’infections nosocomiales. L’'objectif de la thèse a été d’'étudier la contribution des modifications physico-chimiques de surface de matériaux à base de titane sur l’'adhérence de microorganismes. Des surfaces présentant différentes caractéristiques ont été élaborées et l’'adhérence de la bactérie Staphylococcus aureus et de la levure Candida albicans a été testée in vitro en conditions statiques. Des surfaces modèles de TiO2 présentant des rugosités à l’'échelle du nanomètre et du micromètre ont été élaborées avec des wafers de silicium revêtues d’'un film mince d’'oxyde de titane déposé par pulvérisation cathodique. Des surfaces d’'alliages de titane grade 2 et grade 5 ont été modifiées par polissage, sablage ou électroérosion, créant différentes morphologies. Il est apparu que le nombre de microorganismes adhérents changeait certes avec la rugosité, mais était fonction de la morphologie de surface des matériaux et de la taille du microorganisme. Des surfaces lisses de TiO2 ont ensuite été fonctionnalisées par greffage moléculaire pour modifier le caractère hydrophile/hydrophobe de surface. L’'étude de l’'adsorption de protéines du plasma sanguin, par QCM, a permis de mieux expliquer l’'adhérence de bactéries et de levures sur ces surfaces. L’'influence de la nutrition parentérale et des produits de chimiothérapie sur les surfaces a aussi été étudiée afin de se rapprocher des conditions d’'utilisation des chambres implantables
Totally implantable venous-access ports are medical devices used for the administration of chemotherapy drugs and/or parenteral nutrition. Infections can occur and it is indispensable in modern-day medical practice to prevent and reduce the rare infectious complications. In this context, the goal of this work was to study the contribution of the modification of physico-chemical properties of titanium based surfaces on the adherence of microorganisms. Surfaces with different characteristics were produced and the adherence of the bacterium Staphylococcus aureus and the yeast Candida albicans was studied in vitro in static conditions. Model surfaces made of titanium dioxide with roughness from nanometer to micrometer were elaborated using silicon wafers recovered with a thin film of titanium dioxide deposited by plasma vapor deposition. Titanium alloy surfaces (Ti grade 2 and Ti grade 5) were modified by polishing, grit-blasting or wire erosion, to create different surface morphologies. In vitro studies were performed and it was found that the number of adhering microorganisms changed with roughness, but more importantly with the surface morphology of the biomaterials and microorganisms size. Flat titanium dioxide thin films were then functionalized by molecular grafting to modify the hydrophobicity of the surface. Study of plasma protein adsorption, by QCM, allowed to better explain the adherence of bacteria and yeast onto these surfaces. The influence of parenteral nutrition and chemotherapy drugs was also studied in order to better approach the real conditions of totally implantable venous-access ports

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25

Bauer, Oliver [Verfasser]. "Surface bonding of a functionalized aromatic molecule : Adsorption configurations of PTCDA on coinage metal surfaces / Oliver Bauer." Bonn : Universitäts- und Landesbibliothek Bonn, 2015. http://d-nb.info/1080864504/34.

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26

Reynolds, A. E. "Effects of surface additives on the structure and reactivity of transition metal surfaces." Thesis, University of Southampton, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356722.

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27

Zhang, Xieqiu. "Scanning tunneling microscopy study : from clean surface to surfaces adsorbed with atom/cluster or metallic island /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202007%20ZHANG.

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28

Afsharnaderi, M. "Effective exchange interactions for magnetic surfaces, overlayers and surface impurities in the itinerant model of ferromagnetism." Thesis, City University London, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378864.

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29

Hellström, Matti. "Chemistry and Physics of Cu and H2O on ZnO Surfaces : Electron Transfer, Surface Triangles, and Theory." Doctoral thesis, Uppsala universitet, Strukturkemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-236302.

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This thesis discusses the chemistry and physics of Cu and H2O on ZnO surfaces, based primarily on results from quantum chemical calculations. The underlying context is heterogeneous catalysis, where Cu/ZnO-mixtures are used in the industrial synthesis of methanol and in the water gas shift reaction. Electron transfer between small Cu clusters and ZnO is central to this thesis, as are the design and use of models that can describe realistic and very large-scale ZnO surface structures while still retaining the electronic nature of the system. Method and model enhancements as well as tests and validations constitute a large part of this thesis. The thesis demonstrates that the charges of small Cu clusters, adsorbed on the non-polar ZnO(10-10) surface, depend on whether the Cu clusters contain an even or odd number of atoms, and whether water is present (water can induce electron transfer from Cu to ZnO). On the polar Zn-terminated ZnO(0001) surface, Cu becomes negatively charged, which causes it to attract positively charged subsurface defects and to wet the ZnO(0001) surface at elevated temperatures. When a Cu cluster on a ZnO surface becomes positively charged, this happens because it donates an electron to the ZnO conduction band. Hence, it is necessary to use a method which describes the ZnO band gap correctly, and we show that a hybrid density functional, which includes a fraction of Hartree-Fock exchange, fulfills this requirement. When the ZnO conduction band becomes populated by electrons from Cu, band-filling occurs, which affects the adsorption energy. The band-filling correction is presented as a means to extrapolate the calculated adsorption energy under periodic boundary conditions to the zero coverage (isolated adsorbate, infinite supercell) limit. A part of this thesis concerns the parameterization of the computationally very efficient SCC-DFTB method (density functional based tight binding with self-consistent charges), in a multi-scale modeling approach. Our findings suggest that the SCC-DFTB method satisfactorily describes the interaction between ZnO surfaces and water, as well as the stabilities of different surface reconstructions (such as triangularly and hexagonally shaped pits) at the polar ZnO(0001) and ZnO(000-1) surfaces.

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30

Ferguson, Josephus. "Local Charging Behavior on GaN Surfaces." VCU Scholars Compass, 2010. http://scholarscompass.vcu.edu/etd/82.

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Gallium nitride is an important III-V semiconductor which is used in many optoelectronic and high-frequency devices. The nature of the GaN surface and its electrical characteristics can impact the performance of such devices. In this study, several GaN surfaces are locally charged using an atomic force microscope, and then subsequently studied by measuring the surface potential with scanning Kelvin probe microscopy (SKPM). The charging and discharging behavior of the surface appears to be strongly influenced by surface preparation and the presence of a surface oxide layer. If a substantial oxide layer exists, then both positive and negative charging is possible on n-type and p-type samples. Surface treatments and photoemission spectroscopy (XPS) data confirm the presence and influence of the oxide layer on surface charging behavior. In the case of forward-bias charging, a small change in surface contact potential (0.1 – 0.3 eV) is observed that is primarily due to a small voltage drop across the surface oxide. Reverse-bias charging produces a substantially larger change in surface potential (~1 – 3 eV) that must be explained by a large increase in surface band bending. Temperature-dependent SKPM measurements also indicate that the decay behavior of deposited surface charge in dark involves a thermionic mechanism.

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31

Oreopoulos, Lazaros. "Tropical marine stratocumulus albedo and its relation to sea surface temperature." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=56668.

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A review of studies tackling problems on marine stratiform clouds is presented. The strong effect of marine stratocumulus clouds on the top-of-the-atmosphere radiation budget is demonstrated using 5 years of Earth Radiation Budget Experiment (ERBE) data. A relationship between albedo and sea surface temperature (SST) is shown to exist in two areas of the globe that tend to be covered by marine stratocumulus. Albedo increases when SST decreases and vice-versa in both regions when examined on an annual, interannual or spatial basis. The magnitude of the albedo response to a given SST change (1) varies within the regions; (2) differs between the two regions; (3) depends on the type of variability examined; (4) depends on the SST. No useful relations were found between albedo and other meteorological variables. Climatic implications on a global scale arising from the albedo-SST anticorrelation are also discussed.

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32

Ignatiev, Pavel [Verfasser], Patrick [Akademischer Betreuer] Bruno, Ingrid [Akademischer Betreuer] Mertig, and Johannes [Akademischer Betreuer] Barth. "Theoretical study of spin-polarized surface states on metal surfaces / Pavel Ignatiev. Betreuer: Patrick Bruno ; Ingrid Mertig ; Johannes Barth." Halle, Saale : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2009. http://d-nb.info/1024874273/34.

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33

Kambhampati, Patanjali. "Adsorbate-substrate charge transfer excited states /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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34

McAnally, Gerard David. "Analysis of polymer surfaces and thin-film coatings with Raman and surface enhanced Raman scattering." Thesis, University of Strathclyde, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248360.

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35

Xu, Chen. "Advanced Topographic Characterization of Variously Prepared Niobium Surfaces and Linkage to RF Losses." W&M ScholarWorks, 2013. https://scholarworks.wm.edu/etd/1539623621.

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Superconducting radio frequency (SRF) technology is widely adopted in particle accelerators. The shallow penetration (∼ 40 nm) of the RF into superconducting niobium lends great importance to SRF cavity interior surface chemistry and topography. These in turn are strongly influenced by the chemical etching "surface clean-up" that follows fabrication.;The principal surface smoothing methods are buffered chemical polish (BCP) and electropolish (EP). The resulting topography is characterized by atomic force microscopy (AFM). The power spectral density (PSD) of AFM data provides a more thorough description of the topography than a single-value roughness measurement. In this work, one dimensional average PSD functions derived from topography of BCP and EP with different controlled starting conditions and durations have been fitted with a combination of power law, K-correlation, and shifted Gaussian models to extract characteristic parameters at different spatial harmonic scales. While the simplest characterizations of these data are not new, the systematic tracking of scale-specific roughness as a function of processing is new and offers feedback for tighter process prescriptions more knowledgably targeted at beneficial niobium topography for SRF applications.;Process development suffers because the cavity interior surface cannot be viewed directly without cutting out pieces, rendering the cavities unavailable for further study. Here we explore replica techniques as an alternative, providing imprints of cavity internal surface that can be readily examined. A second matter is the topography measurement technique used. Atomic force microscopy (AFM) has proven successful, but too time intensive for routine use. We therefore introduce white light interferometry (WLI) approach as an alternative. We examined real surfaces and their replicas, using AFM and WLI. We find that the replica/WLI is promising to provide the large majority of desired information, so that use of the time-intensive AFM approach can be limited to where it is genuinely necessary.;The prevalent idea is that sharp features could lead to magnetic quench or enhance the thermal quench. In this report, a calculation on magnetic field is numerically given on fine structure by finite element and conformal mapping methods. Corresponding RF Ohmic loss will be simulated. A certain thermal tolerant will be calculated. A Q∼E curve will be predicted from this model.;A perturbation model is utilized to calculate rough surface additional RF loss based on PSD statistical analysis. This model will not consider that superconductor will become iormal at field higher than transition field. Therefore, it is only expected to explain midfield Q performance. One can calculate the RF power dissipation ratio between rough surface and ideal smooth surface within this field range. Additionally, the resistivity of Nb is temperature and magnetic field dependent from classic thermal feedback model theory. Combining with topographic PSD analysis and Rs temperature and field ependency, a middle field Q slope model could be modeled and the contribution from topography can be simulated.

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36

Ben, Embarek Mokhtar. "Préphosphatation au manganèse et phosphatation fer-manganèse des aciers fer-silicium : caractérisation physico-chimique des surfaces et des phosphates formés." Lyon 1, 1996. http://www.theses.fr/1996LYO10181.

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Au cours de ce travail, nous avons etudie l'influence des differentes etapes de la gamme de phosphatation sur la composition et la reactivite de la surface de deux alliages fer-silicium (fev 310 et fev 400) et sur leur aptitude a la phosphatation. Differentes techniques d'analyse et d'observation ont ete utilisees (meb, empa, xps, gdos, leeixs, ftir, pdms, xrfs, tga, xrd et gixd). L'analyse de la surface des alliages fer-silicium etudies montre la presence d'une couche d'oxyde avec un enrichissement en aluminium et silicium pour l'alliage fev 310 et un enrichissement en manganese et silicium pour le fev 400. Ces couches d'oxydes modifient la reactivite de la surface. La presence de l'aluminium et du silicium sont prejudiciables a la phosphatation fer-manganese des substrats, contrairement a celle du manganese qui l'ameliore. Apres le traitement de decapage acide la couche d'oxyde enrichie en aluminium et en silicium a la surface est eliminee rapidement et l'oxyde de fer devient dominant a la surface des deux substrats. Quand un decapage basique est utilise, la couche riche en oxyde de silicium est eliminee lentement tandis que l'oxyde d'aluminium persiste a la surface metallique. La reactivite chimique des surfaces traitees (caractere acido-basique) apres les traitements de decapage chimique a ete comparee par la mesure de l'adherence de divers polymeres, comme le pmma (polymere basique), pvc (polymere acide) et un adhesif commercial ; en utilisant un test de flexion 3 points. Apres le traitement de prephosphatation, nous avons la formation de deux types de phosphates a la surface metallique (l'un de manganese et l'autre de sodium) dont les proportions respectives dependent de la composition de la couche d'oxyde apres decapage chimique. L'etude de l'evolution du poids w (g/cm#2) de la couche de phosphate, en fonction de la duree de la phosphatation, montre une croissance rapide apres un decapage acide et une phase d'initiation (ou d'amorcage) assez longue avant la croissance des cristaux dans le cas du decapage basique. La nature des germes ou des cristaux de phosphate de manganese ou de fer-manganese formes apres prephosphatation ou phosphatation est de type hureaulite (mn, fe)#5 (hpo#4)#2(po#4)#2, 4(h#2o) cristallisant dans le systeme monoclinique

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37

Tait, Steven L. "Desorption kinetics of small n-alkanes from MgO(100), Pt(111), and C(0001)/Pt(111) and studies of Pd nanoparticles : growth and sintering on Al₂O₃(0001) and methane dissociation on MgO(100) /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/9630.

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38

Bigelow, Alan W. "Energy Distribution of Sputtered Neutral Atoms from a Multilayer Target." Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2657/.

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Energy distribution measurements of sputtered neutral particles contribute to the general knowledge of sputtering, a common technique for surface analysis. In this work emphasis was placed on the measurement of energy distribution of sputtered neutral atoms from different depths. The liquid Ga-In eutectic alloy as a sample target for this study was ideal due to an extreme concentration ratio gradient between the top two monolayers. In pursuing this study, the method of sputter-initiated resonance ionization spectroscopy (SIRIS) was utilized. SIRIS employs a pulsed ion beam to initiate sputtering and tunable dye lasers for resonance ionization. Observation of the energy distribution was achieved with a position-sensitive detector. The principle behind the detector's energy resolution is time of flight (TOF) spectroscopy. For this specific detector, programmed time intervals between the sputtering pulse at the target and the ionizing laser pulse provided information leading to the energy distribution of the secondary neutral particles. This experiment contributes data for energy distributions of sputtered neutral particles to the experimental database, required by theoretical models and computer simulations for the sputtering phenomenon.

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39

Chang, Qiang. "Continuous-time random-walk simulation of surface kinetics." The Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=osu1166592142.

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40

Peterson, Joshua T. Knowlton S. F. "Vacuum magnetic flux surface measurements made on the compact toroidal hybrid." Auburn, Ala., 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SUMMER/Physics/Dissertation/Peterson_Joshua_48.pdf.

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41

Panth, Mohan. "USING SURFACE TENSION GRADIENTS AND MAGNETIC FIELD TO INFLUENCE FERROFLUID AND WATER DROPLET BEHAVIOR ON METAL SURFACES." Miami University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=miami1470164188.

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42

Mamo, Andrew Benedict 1982. "Surface roughness of Mars." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32744.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2004.
Includes bibliographical references (p. 35-36).
In this thesis, I created an algorithm to compensate for the saturation of data collected by the Mars Orbiter Laser Altimeter (MOLA). Saturation of the energy measurements had made it impossible to measure surface roughness at 100 m length scales. By calculating the returned energy, the problem of saturation can be avoided. This algorithm was applied to MOLA data across the Martian surface to create an estimate of surface roughness across the planet. The method calculates pulse spreading from returned pulse energy using the link equation. The accuracy of the method is limited by the accuracy of albedo measurements. This analysis improved the estimation of surface roughness on Mars. Further improvements could be gained by correcting for the opacity of atmospheric dust as a cause of pulse spreading.
by Andrew Benedict Mamo.
S.B.

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43

Freixas, Angel Luis. "Surface plasmon resonance experiments." FIU Digital Commons, 2007. http://digitalcommons.fiu.edu/etd/3417.

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In this study, a Surface Plasmon Resonance (SPR) optical sensor, based on Kretschmann configuration, was designed and constructed. SPR is a useful tool for obtaining quantitative kinetic and affinity information on biomolecular interactions. The resolution and the sensitivity of our homemade SPR system was determined and optimized by using thiols and sucrose solutions. The data were normalized and processed to increase the resolution of the system. The sensograms were obtained and the kinetic constants were analyzed. The sensogram of the thiols solutions illustrated the process of association of the thiols on gold surface. The sensogram of the sucrose solutions shown, that the sucrose doesn't have association on gold surface.

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44

Das, Ujjal. "Electronic structure studies of semiconductor surface chemistry and aluminum oxide cluster chemistry." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3344570.

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Анотація:

Thesis (Ph. D.)--Indiana University, Dept. of Chemistry, 2008.
Title from PDF t.p. (viewed Oct. 7, 2009). Source: Dissertation Abstracts International, Volume: 70-02, Section: B, page: 1054. Adviser: Krishnan Raghavachari.

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45

Michalak, David Jason Gray Harry B. "Physics and chemistry of silicon surface passivation /." Diss., Pasadena, Calif. : Caltech, 2006. http://resolver.caltech.edu/CaltechETD:etd-05082006-074414.

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46

Hellwig, Maren [Verfasser], Christian [Gutachter] Linsmeier, and Achim von [Gutachter] Keudell. "Influence of 3D geometry and surface roughness on plasma-wall interaction processes on tungsten surfaces / Maren Hellwig. Gutachter: Christian Linsmeier ; Achim von Keudell." Bochum : Ruhr-Universität Bochum, 2016. http://d-nb.info/1105036073/34.

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47

Grönhagen, Niklas [Verfasser], Heinz [Akademischer Betreuer] Hövel, and Markus [Akademischer Betreuer] Betz. "Cluster-Surface Interaction of Mass Selected Ag Clusters with Graphite, Gold and C60 Functionalized Surfaces / Niklas Grönhagen. Betreuer: Heinz Hövel. Gutachter: Markus Betz." Dortmund : Universitätsbibliothek Dortmund, 2011. http://d-nb.info/1098312120/34.

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48

Subedi, Laxmi P. "AFM Tip-Graphene-Surface Interactions." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1291144388.

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49

Prähofer, Michael. "Stochastic Surface Growth." Diss., lmu, 2003. http://nbn-resolving.de/urn:nbn:de:bvb:19-13818.

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50

Venegas, Silvia Andrea. "Interannual variability of the sea surface temperature and the overlying atmospheric circulation in the western South Atlantic." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23948.

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Анотація:

The interannual variability of the sea surface temperature (SST) in the western South Atlantic Ocean is explored by applying the composite analysis method to a 40-year period of COADS data (1953-1992). Interactions between the ocean and the overlying atmosphere, as well as oceanic processes, are investigated in order to explain the variability in the SST associated with the two converging western boundary currents in this region: the Brazil and the Malvinas Currents.
The pattern of interannual variability of SST displays a dipole-like structure in the vicinity of the confluence of the two currents. That is, the SST fluctuations in both currents are roughly out-of-phase: warm episodes in one current accompany cold episodes in the other. It is suggested that the variability in the oceanic advection of the currents accounts for part of the observed variability in SST in the confluence region, the dipole pattern being associated with the strength of the temperature gradient in the confluence.
The pattern of variability of the air-sea heat exchange associated with the observed SST fluctuations displays a distribution of ocean-to-atmosphere flux anomalies roughly out-of-phase with those of SST. It is concluded that the SST fluctuations associated with the Brazil and Malvinas Currents are related to the variability in both the air-sea heat exchange and the oceanic advection of the currents.
The warm and cold events observed in the currents are associated with distinct atmospheric circulation patterns. Thus, it is suggested that changes in the atmospheric circulation on interannual timescales induce anomalies in the air-sea heat exchange, which have been found to be partly responsible for the variability in SST of the Brazil and Malvinas Currents.

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