Dissertations / Theses: 'Surfaces'

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Kruithof, Nico Gerard Hugo. "Envelope surfaces surface design and meshing /." [S.l. : [Groningen : s.n.] ; University Library Groningen] [Host], 2006. http://irs.ub.rug.nl/ppn/292152264.

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Johansson, Lars. "SURFACE DRAG MODELING FOR MILLED SURFACES." Thesis, KTH, Mekanik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-204017.

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One of the governing sources of energy loss in a modern day jet engine is attributed to surfacedrag. This energy loss can be divided into friction loss and to surface geometry loss. Thefriction loss is the shear stress the fluid experience due to a no slip condition at the wall, whilethe surface geometry loss is due to pressure drop when the fuel passes an obstacle.The objective of this work is to study the drag coefficient of a plate for different types ofmilled tracks and for different kinds of flow conditions. The theories used to calculate thedrag coefficient are based on the momentum thickness theory including shear stress- andpressure integration. The computations were carried out with ANSYS CFX assuming a ShearStress Transport 𝑘 − 𝜔 turbulence model. The steady state flow conditions tested are varyingboundary layer thicknesses, milled track heights, milled track widths, Reynolds numbers overthe milled track height, Reynolds numbers over the plate length and free-stream angle ofattack. By knowing what affects the drag coefficient for different types of milled tracks, morepractical models can be developed making the prediction of surface drag inside the jet enginemore accurate.This report has resulted in a formula that predicts the drag coefficient for different types ofmilled surfaces. The formula is derived from the assumption that the CFD results on ANSYSCFX are correct. A physical test has not been made to verify those results, however this has tobe done to prove that this formula is valid.

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Zheleva, Zhasmina Vasileva. "Surface crystallography of complex and disordered surfaces." Thesis, University of Reading, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553057.

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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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Myshlyavtsev, Alexander V., and Marta D. Myshlyavtseva. "Modeling of surface diffusion for stepped surfaces." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-193477.

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Coulson, Stephen Richard. "Liquid repellent surfaces." Thesis, Durham University, 2000. http://etheses.dur.ac.uk/761/.

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The work in this thesis is primarily aimed at supporting the NBe (Nuclear, Biological and Chemical) aspect of Crusader 21, the military clothing programme for the early 21st Century. This aims to produce a multi-purpose, systems-orientated combat ensemble for the UK Armed Services. Conventional "wet" techniques for chemically modifying fabrics have certain disadvantages, however employing plasma technology may provide a route for many novel "multi-functional effects" fabrics such as repellency against toxic chemical agents. In order to produce repellent coatings the surface must have a low surface energy. To obtain this, inert chemical groups need to be attached to the solid substrate. In addition to chemistry, surface roughness plays an important role in repellency. Liquid repellent surfaces have been produced by the pulsed plasma polymerisation of I H, 1 H,2H,2H -heptadecafluorodecyl acrylate. These films have chemical functionalities indicative of polymerisation occurring through the acrylate double bond, as shown by Infrared Spectroscopy analysis. Structural retention was optimised using experimental design techniques and resulted in a critical surface tension of wetting as low as 4.3 mN m-I (c.f. Teflon 18.5 mN m-I). Plasma deposition of a functionalised surface followed by reaction with a fluorinated alcohol proved less affective. Enhanced deposition rates for 1 H, 1 H,2H-perfluorododec-I-ene, over the saturated analogue, have indicated that polymerisation can occur during the off-time of the pulsed plasma period, via free radical polymerisation pathways. X-ray Photoelectron Spectroscopy (XPS) has indicated greater structural group retention for monomers containing double bonds. In order to obtain super liquid repellency the effect of surface roughness was investigated, where both commercially available rough surfaces and plasma roughened substrates were utilised. Once optimised, the rough surfaces were coated with 1 H, 1 H,2H,2H-heptadecafluorodecyl acrylate and produced super repellent films.

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Lee, Chee-kwan. "Modelling of flexible surfaces using a point mass system /." [Hong Kong : University of Hong Kong], 1992. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13204889.

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Yan, Liling. "Effects of surface topography on hydrophobicity of surfaces with spherical micro-protusions." Thesis, The University of Sydney, 2005. https://hdl.handle.net/2123/27892.

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The water repellency of a surface is principally governed by a combination of its chemical nature (i.e. surface energy) and topographical microstructure. The surface energy is an intrinsic property of a material that can be controlled by chemical modification, and other factors that can affect wettability, especially the surface topography were investigated. In particular, the study of topographical factors influencing the wettability of solid films is very important in View of production of surfaces with tailored properties and functions. The main objective of this research was to investigate the effect of surface topography on surface hydrophobicity. Particular emphasis was given to those surfaces with a particulate-like structure, which is one of the most popular surface features in natural and man-made superhydrophobic surfaces. Surfaces with particulate-like structure from both real superhydrophobic surface and model surfaces were characterized.

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Burton, Zachary Travis. "Surface characterization, adhesion, and friction properties of hydrophobic leaf surfaces and nanopatterned polymers for superhydrophobic surfaces." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1160489659.

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Dalpé, Denis. "Schwarz's surface and the theory of minimal surfaces." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0023/MQ39958.pdf.

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Roach, Paul. "Measurement of surface-protein interactions on novel surfaces." Thesis, Nottingham Trent University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431900.

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This thesis is concerned with the fundamental principles affecting protein adsorption. The effects of surface chemistry and topography on protein adsorption characteristics have been identified and quantified. Particular attention has been made to understand how the conformation of surface-bound proteins was affected by the surface onto which they adsorbed. Quartz crystal microbalance (QCM), UV-Vis spectroscopy and fluorometry were used to assess protein-surface affinity and amounts of protein adsorbed at surface saturation levels. Infrared spectroscopy was used to quantify protein conformational changes incurred upon adsorption. A fluorescent assay protocol was developed for use as an external calibration method for the quantification of adsorbed protein an d the results obtained were compared with QCM and an amido black protein assay of the same systems. Model experiments were performed using bovine fibrinogen (an elongated molecule) and albumin (a globular molecule) adsorbing onto flat hydrophilic (OH terminated) and hydrophobic (CH3 terminated) surfaces in the first instance, but later superhydrophilic and superhydrophobic surfaces were also studied. Surface curvature on the nano-scale was used to model topography, wherein protein molecules adsorbed onto spherical substrates (15-165 nm diameter) having chemically defined surfaces. Results obtained indicate that both proteins exhibit a less organised secondary structure upon adsorption onto hydrophobic compared to hydrophilic surfaces, with this effect being greatest for albumin. Adsorption rates and binding affinities were found to be higher on hydrophobic surfaces although the amounts adsorbed at saturation were lower. Supporting spectroscopic data suggests that proteins undergo surface induced deformation upon adsorption. Topography was shown to compound the effects of surface chemistry, with fibrinogen being more denatured on surfaces presenting high surface curvature whereas albumin was more denatured on larger substrates. These effects are most probably due to the differing size and shape of the proteins investigated. This study highlights the possibility of using tailor-made surfaces to influence binding rates and the conformation of bound proteins through protein-surface interactions. The data presented in this thesis demonstrates our ability to control protein adsorption characteristics through careful consideration of the underlying surface, which may facilitate the development and fabrication of materials / surface coatings with tailored bioactivity.

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Severn, Kathryn A. "Science of synthetic turf surfaces : player-surface interactions." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/7216.

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This research project has investigated the mechanical properties and behaviour of third generation synthetic turf surfaces used for football and rugby, with a focus on the traction behaviour produced at the shoe-surface interface. The physical characteristics and mechanical properties of the component materials used in the construction of third generation surfaces were examined. The bulk density of the rubber infill material was found to be a key variable. This was shown to be influenced by compaction and the resulting compression of the rubber infill material under an applied load. Increasing the compactive effort and/or compression under loading increased the bulk density. Shear strength of the rubber infill material was shown to be influenced by bulk density, increasing with a higher bulk density. The composite surface system behaviour of third generation synthetic turf surfaces was investigated. Several surface variables were measured including; shockpad thickness, synthetic turf carpet construction, infill thickness, infill bulk density and infill material type. Shockpad thickness, rubber infill thickness and bulk density were found to influence the impact behaviour, with a thicker rubber layer (shockpad and/or rubber infill layer) reducing the hardness of a surface system. Increasing the bulk density of the rubber infill with compactive effort increased the surface system hardness. Traction behaviour of composite surface systems was explored using three traction test methods to measure both rotational and translational traction. Rubber infill bulk density was shown to be a primary influencing variable from the playing surface variables investigated. Several further traction variables were explored to provide a fuller understanding of the mechanisms involved in the production of traction at the shoe-surface interface including; vertical stress, stud configuration, stud dimension, stud penetration, water and temperature. Vertical stress and stud configuration were found to be primary variables influencing traction development. A traction framework has been developed identifying the factors affecting the production of traction at the shoe-surface interface. It is intended that the traction framework can be used by the sports surface industry, sports governing bodies and academia to aid in the decisions and judgements made during the design, construction and maintenance of these surfaces to obtain desired characteristics and optimise performance and safety.

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Wang, Jialin. "AFM surface force measurements between hydrophobized gold surfaces." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/29031.

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In 1982, Israelachvili and Pashley reported the first measurements of a hitherto unknown attractive force between two mica surfaces hydrophobized in cetyltrimethylammonium bromide (CTAB) solutions. Follow-up experiments conducted by many investigators confirmed their results, while others suggested that the â hydrophobic forceâ is an artifact due to nanobubbles (or cavitation). Evidences for the latter included the discontinuities (or steps) in the force versus distance curves and the pancake-shaped nano-bubbles seen in atomic force microscopic (AFM) images. Recent measurements conducted in degassed water showed, however, smooth force versus distance curves, indicating that the hydrophobic force is not an artifact due to nanobubbles.1, 2 Still other investigators3, 4 suggested that the long-range attraction observed between hydrophobic surfaces is due to the correlation between the patches of adsorbed ionic surfactant and the patches of unoccupied surface. For this theory to work, it is necessary that the charged patches be laterally mobile to account for the strong attractive forces observed in experiment. In an effort to test this theory, AFM force measurements were conducted with gold substrates hydrophobized by self-assembly of alkanethiols and xanthates of different chain lengths. The results showed long-range attractions despite the fact that the hydrophobizing agents chemisorb on gold and, hence, the adsorption layer is immobile. When the gold surfaces were hydrophobized in a 1 Ã 10-3 M thiol-in-ethanol solution for an extended period of time, the force curves exhibited steps. These results indicate that the long-range attractions are caused by the coalescence of bubbles, as was also reported by Ederth.5 The steps disappeared, however, when the species adsorbed on top of the chemisorbed monolayer were removed by solvent washing, or when the gold substrates were hydrophobized in a 1 Ã 10-5 M solution for a relatively short period of time. AFM force measurements were also conducted between gold substrates coated with short-chain thiols and xanthates to obtain hydrophobic surfaces with water contact angles (ï ±) of less than 90o. Long-range attractions were still observed despite the fact that cavitation is thermodynamically not possible. Having shown that hydrophobic force is not due to coalescence of pre-existing bubbles, cavitation, or correlation of charged patches, the next set of force measurements was conducted in ethanol-water mixtures. The attractive forces became weaker and shorter-ranged than in pure water and pure ethanol. According to the Derjaguinâ s approximation6, an attractive force arises from the decrease in the excess free energy (ï §f) of the thin film between two hydrophobic surfaces.7 Thus, the stronger hydrophobic forces observed in pure water and pure ethanol can be attributed to the stronger cohesive energy of the liquid due to stronger H-bonding. Further, the increase in hydrophobic force with decreasing separation between two hydrophobic surfaces indicates that the H-bonded structure becomes stronger in the vicinity of hydrophobic surfaces. The force measurements conducted at different temperatures in the range of 10-40ÂºC showed that the hydrophobic attraction between macroscopic surfaces causes a decrease in film entropy (Sf), which confirms that the hydrophobic force is due to the structuring of water in the thin film between two hydrophobic surfaces. The results showed also that the hydrophobic interaction entails a reduction in the excess film enthalpy (Hf), which may be associated with the formation of partial (or full) clathrates formed in the vicinity of hydrophobic surfaces. The presence of the clathrates is supported by the recent finding that the density of water in the vicinity of hydrophobic surfaces is lower than in the bulk.8
Ph. D.

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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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Sasián, José, Dmitry Reshidko, and Chia-Ling Li. "Aspheric/freeform optical surface description for controlling illumination from point-like light sources." SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS, 2016. http://hdl.handle.net/10150/622704.

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We present an optical surface in closed form that can be used to design lenses for controlling relative illumination on a target surface. The optical surface is constructed by rotation of the pedal curve to the ellipse about its minor axis. Three renditions of the surface are provided, namely as an expansion of a base surface, and as combinations of several base surfaces. Examples of the performance of the surfaces are presented for the case of a point light source. (C) 2016 Society of Photo-Optical Instrumentation Engineers (SPIE)

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Vandadi, Aref. "Optimization of Superhydrophobic Surfaces to Maintain Continuous Dropwise Condensation." Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc500016/.

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In the past decade, the condensation on superhydrophobic surfaces has been investigated abundantly to achieve dropwise condensation. There is not a specific approach in choosing the size of the roughness of the superhydrophobic surfaces and it was mostly selected arbitrarily to investigate the behavior of condensates on these surfaces. In this research, we are optimizing the size of the roughness of the superhydrophobic surface in order to achieve dropwise condensation. By minimizing the resistances toward the transition of the tails of droplets from the cavities of the roughness to the top of the roughness, the size of the roughness is optimized. It is shown that by decreasing the size of the roughness of the superhydrophobic surface, the resistances toward the transition of the tails of droplets from Wenzel state to Cassie state decrease and consequently dropwise condensation becomes more likely.

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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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DeMaio, Ernest Vincent 1964. "Surfaces." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/73301.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1989.
Supervised by Dennis Frenchman. Vita.
Includes bibliographical references (leaves 146-150).
Surfaces is a collection of four individual essays which focus on the characteristics and tactile qualities of surfaces within a variety of perceived landscapes. Each essay concentrates on a unique surface theme and purpose; each essay offers observations and speculations with regard to surface qualities; and each essay is grounded in case studies which accentuate these surface qualities. Although the four individual essays stand alone in their theme and message, the consideration of all four essays yields a greater understanding of the concept of "surface" as a single entity . Conclusions and observations are reinforced through an analysis of building materials, photography and media, fashion, city form, and historic preservation. Among the themes investigated in this thesis are: the "Communication" of surface image (the influence of high- technology photo-media upon our surface values and expectations - allowing us total control over any scene, material, or message); the "Permanence" and production of surfaces (the need for modem materials to retain their surface qualities, regardless of age, wear, or environmental abuse - and our changing expectations of these surfaces); surface "Veneer" (the tendency for all materials to become increasingly thin "veneers" as a result of modern surface fabrication processes); and surface "Preservation" (our increasing awareness of the cultural value of historic surfaces - and the inconsistencies of our existing preservation philosophies). The intention of this thesis is to observe changes in our perceptions and expectations of our physical environment - and hypothesize the relationship between these expectations and the materials and methods used to create the built environment. As technological innovations create new forms of surface expression, there is a corresponding change in our expectations and perceptions of the physical environment. This thesis will investigate the implications and repercussions of these changing expectations, and speculate their influence upon the future of surface - in a world which places increasing value in surface rather than substance.
by Ernest Vincent DeMaio.
M.S.

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Funkhouser, Rob. "Surfaces." Digital Commons @ Butler University, 2017. https://digitalcommons.butler.edu/grtheses/492.

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Surfaces is a work for two percussionists in four movements. It uses a variety of small percussion instruments, keyboard percussion, and two specially built kalimbas. This document contains both the score and an analysis of the piece that covers instrument choice, performance practice, form and compositional techniques employed

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Greene, George W. IV. "Surface modification of sintered porous polyethylene membrane." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/20126.

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Cole, D. J. "Surface chemistry and adhesive properties of oxidised Si surfaces." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597835.

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I have used density functional theory and classical molecular dynamics to study the chemistry of the native oxide layer on the Si(100) surface. Surface oxidation is accompanied by the development of tensile surface stress and by formation of Si species with a range of oxidation states. Total energy calculations of P and B substitution into the oxide layer and first principles molecular dynamics simulations of oxide growth on the doped surface both indicate a surface oxidation mechanism whereby impurities remain trapped at the Si/SiO_x interface. A new two- and three-body classical potential is developed to simulate the hydroxylated, natively oxidised Si surface in contact with water solutions and biological molecules. The potential parameters are chosen to reproduce the structure, charge distribution, tensile stress and interactions with single water molecules of a natively oxidised Si surface previously obtained by ab initio simulations. I apply this classical potential to study the atomic-level processes that determine the mutual adhesion between hydrophilic Si wafers during room temperature bonding. Moreover, I have investigated the adhesion mechanisms of proteins such as collagen and human serum albumin, which mediate the interactions between cells and implanted Si-based devices.

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Plaisance, Marc Charles. "Cellular Response to Surface Wettability Gradient on Microtextured Surfaces." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/53730.

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Objective: Topography, chemistry, and energy of titanium (Ti) implants alter cell response through variations in protein adsorption, integrin expression, and downstream cell signaling. However, the contribution of surface energy on cell response is difficult to isolate because altered hydrophilicity can result from changes in surface chemistry or microstructure. Our aim was to examine a unique system of wettability gradients created on microstructured Ti on osteoblast maturation and phenotype. Method: A surface energy gradient was created on sand-blasted/acid-etched (SLA) Ti surfaces. Surfaces were treated with oxygen plasma for 2 minutes, and then allowed to age for 1, 12, 80, or 116 hours to generate a wettability gradient. Surfaces were characterized by contact angle and SEM. MG63 cells were cultured on SLA or experimental SLA surfaces to confluence on TCPS. Osteoblast differentiation (IBSP, RUNX2, ALP, OCN, OPG) and integrin subunits (ITG2, ITGA5, ITGAV, ITGB1) measured by real-time PCR (n=6 surfaces per variable analyzed by ANOVA/Bonferroni’s modified Student’s t-test). Result: After plasma treatment, SLA surface topography was retained. A gradient of wettability was obtained, with contact angles of 32.0° (SLA116), 23.3° (SLA80), 12.5° (SLA12), 7.9° (SLA1). All surfaces were significantly more hydrophilic than the original SLA surface (126.8°). Integrin expression was affected by wettability. ITGA2 was higher on wettable surfaces than on SLA, but was highest on SLA1. ITGAV and ITGB1 were decreased on hydrophilic surfaces, but ITGA5 was not affected. IBSP, RUNX2, and ALP increased and OPG decreased with increasing wettability. OCN decreased with increasing wettability, but levels on the most wettable surface were similar to SLA. Conclusion: Here we elucidated the role of surface energy on cell response using surfaces with the same topography and chemistry. The results show that osteoblastic maturation was regulated in a wettability-dependent manner and suggest that the effects are mediated by integrins.

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Ye, Fan. "Surface plasmon polaritons along metal surfaces with novel structures." Thesis, Boston College, 2014. http://hdl.handle.net/2345/bc-ir:103747.

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Thesis advisor: Michael J. Naughton
Surface plasmon polaritons (SPPs) are hybridized quasiparticles of photons and electron density waves. They are confined to propagate along metal-dielectric interfaces, and decay exponentially along the direction perpendicular to the interfaces. In the past two decades, SPPs have drawn intensive attention and undergone rapid development due to their potential for application in a vast range of fields, including but not limited to subwavelength imaging, biochemical/biomedical sensing, enhanced light trapping for solar cells, and plasmonic logic gates. These applications utilize the following intrinsic properties of SPPs: (1) the wavelength of SPPs is shorter (and can be much shorter) than that of free photons with the same frequency; (2) the local electric field intensity associated with SPPs can be orders of magnitude larger than that of free photons; and (3) SPPs are bound to metal surfaces, and are thus easily modulated by the geometry of those surfaces. Here, we present studies on SPPs along metal surfaces with novel structures, including the following: (1) SPP standing waves formed along circular metal surfaces that lead to a "plasmonic halo" effect; (2) directional reflectionless conversion between free photons and SPPs in asymmetric metal-insulator-metal arrays; and (3) broadband absorbance enhancement of embedded metallic nanopatterns in a photovoltaic absorber layer. These works may prove useful for new schemes for SPP generation, plasmon-photon modulation, ultrasensitive dielectric/bio sensing, and high efficiency thin film solar cells
Thesis (PhD) — Boston College, 2014
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Physics

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Soldemo, Markus. "Transition metal oxide surfaces : Surface structures and molecular interaction." Doctoral thesis, KTH, Materialfysik, MF, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-196130.

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Metal oxides are both corrosion products and useful materials with a wide range of applications. Two of the most used metals today are iron and copper. In this thesis, surface structures and molecular interaction with surfaces of iron oxides and copper oxides are studied using spectroscopy and microscopy methods. The surface structures of iron oxides grown on the low-index iron (Fe) surfaces (100) and (110) have been studied during the initial oxidation phase. The oxidation condition for both iron surfaces was 400 °C and 1×10−6 mbar of oxygen gas. For the Fe(100)-surface, a Fe3O4(100)-film is formed beyond the oxygen adsorbate structures. For the Fe(110)-surface, a FeO(111)-film is first formed. When the FeO(111)-film grows thicker, it transforms into a Fe3O4(111)-film. The surface structures of Cu2O(100) was studied and the main finding is that the most common surface structure that previously in literature has been described to have a periodicity of (3√2×√2)R45° actually has a periodicity described by the matrix (3,0;1,1). Furthermore, the low-binding energy component in the photoelectron spectroscopy O 1s-spectrum is determined to origin from surface oxygen atoms. Sulfur dioxide, a corrosive molecule that in the environment to large share comes from human activities such as burning of fossil fuels, was studied using photoelectron spectroscopy when interacting with surfaces of iron oxide thin films and bulk Cu2O-surfaces. On the iron oxide thin film surfaces under ultra-high vacuum conditions, sulfur dioxide adsorbs partly as SO4-species and partly dissociates and forms FeS2. On the Cu2O-surfaces under ultra-high vacuum conditions, the adsorption of sulfur dioxide is non-dissociative and forms SO3-species. When interacting with near-ambient pressures of water, it is observed in the photoelectron spectroscopy S 2p-region that the sulfur from SO3-species shifts to Cu2S.

QC 20161114

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Chakrabarty, Souvik. "NOVEL SOFT SURFACES WITH INTERESTING SURFACE AND BULK MORPHOLOGY." VCU Scholars Compass, 2012. http://scholarscompass.vcu.edu/etd/397.

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The goal of this research is to cover a broad set of scientific investigations of elastomeric materials based on polydimethylsiloxane (PDMS) and poly((3,3,3-trifluoroethoxymethyl)methyloxetane) diol. The scope of study covers five areas, well correlated with each other. The first study investigates the near surface morphology of condensation cured PDMS as a function of increasing the amount of siliceous phase. The appearance, disappearance and reappearance of untreated fumed silica nanoparticles at the PDMS near surface and their correlation with the volume fraction of siliceous phase have been studied. This research with PDMS nanocomposites has led to the development of an alternative route for improving mechanical strength of PDMS elastomers, conventionally known to have weak mechanical properties. The second study involves synthesis of a triblock copolymer comprising of four mutually immiscible phases, namely, soft segments comprising of fluorous and silicone domains, a diisocyanate hard segment and a glassy siliceous phase. Structure-property relationship has been established with an investigation of the interesting surface and bulk morphology. The highly improved mechanical strength of these soft materials is noteworthy. The dominance of silicone soft block at the triblock near surface has led to the third study which investigates their potential non-adhesive or abhesive characteristic in both a laboratory scale and in a marine environment. The peak removal stress and the removal energy associated with the detachment of a rigid object from the surface of these triblock copolymers have been measured. Results obtained from laboratory scale experiments have been verified by static immersion tests performed in the marine environment, involving the removal of adhered soft and hard fouling organisms. Gaining insights on the characteristics of an easy release surface, namely low surface energy and a low near surface modulus, a new way for controlling the near surface composition for elastomeric coatings have been developed. This technique involves an elastomer end-capped with a siliceous crosslinking agent and a tough, linear polyurethane. The basic concept behind the hybrid compositions is to develop a coating suitable for foul release applications, having a low energy surface, low surface modulus but good bulk mechanical strength. Henceforth, the fourth study deals with synthesis and characterization of the hybrid polymers over a wide range of composition and investigates their foul release characteristic in laborartory scale experiments. In our final study, attempts have been made in generating a silicone coating with antimicrobial property. A quaternary alkylammonium in different weight percents have been incorporated into a conventional, condensation cured polydimethylsiloxane (PDMS) elastomer. Antimicrobial assay has been performed on these modified silicone coatings to assess their biocidal activity against strains of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. Surface accessibility of quaternary charges has been quantified by measuring the streaming potential of a modified coating. An effort has been made in improving the mechanical strength of the weak PDMS elastomers by adding treated fumed silica nanoparticles as reinforcements. The effect of adding fillers on the mechanical property (tensile), surface concentration of quaternary charge and on the biocidal activity of a representative sample has been investigated.

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Guan, Yanlin. "Interactive and immersive surface interrogation techniques over triangulated surfaces." Diss., Mississippi State : Mississippi State University, 2003. http://library.msstate.edu/etd/show.asp?etd=etd-04142003-173417.

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Stewart, Shona Diane. "Surface enhanced Raman scattering on electrochemically prepared silver surfaces." Thesis, Queensland University of Technology, 1999.

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Chen, Yizhou. "Adhesion of Spider Glue on Different Surface Energy and Surface Potential Surfaces." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1462227997.

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Lê, Thanh-Tâm. "Surfaces lagrangiennes dans les surfaces projectives complexes." Paris 7, 2002. http://www.theses.fr/2002PA077104.

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Duran, James Joseph. "Differential geometry of surfaces and minimal surfaces." CSUSB ScholarWorks, 1997. https://scholarworks.lib.csusb.edu/etd-project/1542.

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李志坤 and Chee-kwan Lee. "Modelling of flexible surfaces using a point mass system." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B31210399.

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Bråmå, Erik. "Strain Energy of Bézier Surfaces." Thesis, Linköpings universitet, Matematik och tillämpad matematik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-145645.

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Bézier curves and surfaces are used to great success in computer-aided design and finite element modelling, among other things, due to their tendency of being mathematically convenient to use. This thesis explores the different properties that make Bézier surfaces the strong tool that it is. This requires a closer look at Bernstein polynomials and the de Castiljau algorithm. To illustrate some of these properties, the strain energy of a Bézier surface is calculated. This demands an understanding of what a surface is, which is why this thesis also covers some elementary theory regarding parametrized curves and surface geometry, including the first and second fundamental forms.

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Poirier, Jason S. "Polymer Templating in Surfactant Monolayers." Fogler Library, University of Maine, 2004. http://www.library.umaine.edu/theses/pdf/PoirierJS2004.pdf.

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Andrews, Marilyn Mockus 1958. "Characterization of the surface acidity of passivated iron particles by flow microcalorimetry." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276614.

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The characteristics of passivated iron particles have been examined with flow microcalorimetry to determine the acidic nature of the surface sites. The molar heat of adsorption of pyridine from hexane was measured with a FMC and a differential refractive index detector, at 23 and 40°C. The adsorption data were found to obey the assumptions of the Freundlich isotherm. The adsorption densities at different temperatures were used to calculate the isosteric heat of adsorption. The molar heat of adsorption of triethylamine from hexane was also measured and combined with the data for pyridine in order to calculate the Drago constants for the iron particles. A static adsorption method was used for the adsorption of pyridine from hexane onto the iron particles, for comparison with the dynamic method. The heat of wetting for the iron particles, with hexane, has also been measured. The iron particles were examined with X-ray diffraction. Mossbauer spectroscopy, XPS, SEM, TEM, and electrophoresis to characterize the surface layer. These techniques have revealed that the iron particles are coated with ferric oxide and this surface is amphoteric in aqueous solutions.

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Nguyen, Tan Khoi. "Surfaces polyédriques et surfaces paramétriques : une reconstruction par approximation via les surfaces de subdivision." Thesis, Aix-Marseille 2, 2010. http://www.theses.fr/2010AIX22055/document.

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La Conception Assistée par Ordinateur (C.A.O) qui permet de concevoir des objets physiques à partir de modèles mathématiques est utilisée dans de nombreux secteurs de l’industrie.On constate actuellement une volonté généralisée de tirer parti de deux approches jusqu’à présent plutôt antagonistes : la modélisation géométrique continue qui crée des objets continus représentant par la modélisation à partir de surfaces B-splines ou NURBS) et la modélisation géométrique discrète qui qu’il s’agisse de maillages ou de surfaces de subdivision.Cette dualité d’approche a de nombreuses applications industrielles potentielles et présente donc un intérêt scientifique important. Les surfaces polyédriques et en particulier les surfaces de subdivision offrent intrinsèquement la discrétisation, sont d’une manipulation très simple, mais elles ne remplacent pas les surfaces B-splines ou NURBS. Les travaux présentés dans la thèse et qui ont abouti au passage réciproque d’une surface paramétrique à une surface polyédrique. Nous nous intéressons plus particulière aux surfaces de subdivision considérant comme une liaison entre la surface polyédriquee et la surface paramétrique parce qu’après quelques étapes de subdivision, le polyèdre caractéristique converge à une surface paramétrique correspondant. Nous y proposons des schémas de la subdivision inverse permettent de récréer les surface polyédrique grossier de subdivision précédent. Nous avons donc développé deux méthodes pour la reconstruction d’une courbe/surface paramétrique en utilisant le schéma de subdivision inverse uniforme et le schéma de subdivision inverse non-uniforme. Pour améliorer les résultats de reconstruction par la subdivision inverse, nous associons à ces méthodes une possibilité d’ajustement d’approximation qui permet de diminuer grandement l’erreur de reconstruction. Les résultats obtenus ont été comparés à une méthode bien connu de reconstruction sens au sens des moindres carrés. Nos méthodes sont très prometteuses en termes d’approximation et de compression
Computer Aided Geometric Design (CAGD) which allows us to design the physical objects from mathematical models is used in many sectors of industry. It is currently a general wish to take advantage of the two these approaches rather than the antagonists : The goal that the continuous geometric model creates the continuous objects represented by the modelof the surfaces B-splines or NURBS) and the discreet geometric model made by eitherthe meshes or the subdivision surfaces. This duality of the approach has many potential industrial applications and therefore submits interesting significant science. The polyhedral surfaces and the subdivision surfaces in particular which offer the intrinsically discretization,are a very simple manipulation, but they do not replace the surfaces B-splines or NURBS.The works presented in this thesis aim to the reciprocal passage from a parametric surfaceto a polyhedral surface. We are more specialy interested to subdivisions surfaces considering as a liaison between the polyhedral surface and the parametric surface, because after a few steps of subdivision, the polyhedron characteristic converges to a parametric surface corresponding.We have proposed the schemas of the inverse subdivision allowing recreating the polyhedral surface coarse of subdivision precedent. We thus presented two methods for there construction of a parametric curve/surface : one for using the schema of uniform inverse subdivision and the other for non-uniform inverse subdivision. To improve the results of reconstruction by the inverse subdivision methods, we associate these methods with the process of adjustment the approximation which allows reducing the error of reconstruction.The results obtained have been compared with a well-known least squares method. Our methods are very promising in terms of approximation and compression

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Lawson, Glenn E. "The effects of evaporation rate, solvent, and substrate on the surface segregation of block copolymers." Thesis, This resource online, 1985. http://scholar.lib.vt.edu/theses/available/etd-03042009-041008/.

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Palethorpe, S. J. "Calcium sulphate deposition on heated metal surfaces." Thesis, University of Birmingham, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311098.

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The accumulation of undesired matter at heat transfer surfaces (fouling) is a severe problem to industry. The growth of calcium sulphate dihydrate on heated metal surfaces has been examined and a mechanism for the effect of surface roughness on the amount of deposition has been proposed. A novel piece of equipment was designed and constructed in which the growth of crystals on heat transfer surfaces with different surface roughnesses could be observed under controlled solution conditions. The test section was a transparent rectangular channel into Rhich three 25 mm diameter test pieces could be inserted such that the polished faces were planar with the rear face of the channel. The back faces of these test pieces were heated by contact with hot Mater. Using Reynolds numbers of 300 to 13,500 and calcium sulphate 2+ solutions with bulk concentrations from 20 to 50 mH Ca , no gross effect due to surface roughness was seen. However a limited effect, which distinguished grit-blasted surfaces from polished surfaces, was 2+ found in experiments with a bulk concentration from 28 to 33 mH Ca . In all of the experiments it was observed that the presence of bubbles enhanced crystal growth. It was also found that the amount of deposition formed on any surface decreased with decreasing dissolved oxygen content of the bulk solution. It is suggested that a bulk concentration of approximately 33 mH 2+ Ca is a critical level of supersaturation, which corresponds with the so-called metastable limit of supersaturation. The surface roughness effect may be associated with two factors. Firstly, as the critical supersaturation is approached crystal growth is enhanced at certain sites. in particular the edges of bubbles. Secondly, very rough surfaces. such as grit-blasted surfaces. more readily support and initiate bubble formation and consequently the grit-blasted surface shows greater growth. Additional work with a different test rig. using a stagnant solution, indicated that suppression of bubble formation during an experiment, either by initially degassing the surface or by pressurising the system, decreased the amount of crystal growth. This work suggests that a surface roughness effect exists which is related to the presence of bubbles at the surface. Consequently the amount of deposition can be decreased either by controlling the formation of the bubbles (e.g. by completely degassing both the solution and the surface. and pressurising the system). or by polishing the surface. However. the surface roughness effect was most apparent between the very coarse, grit-blasted surfaces (R ~ 2.90 um) and the a medium finish 180 or 240 Grit surfaces (R ~ 0.23 um). a Little or no further improvement was obtained in polishing to a mirror finish. i. e. 0.25 or 0.1 um (R ~ 0.03 um). a further polishing beyond removing gross roughness would not appear to Therefore. for industrial purposes, yield sufficient benefit to justify the large cost involved. It is recommended that further work be undertaken to determine whether the deposition which occurs in the absence of bubbles is influenced by the surface roughness, and whether other chemical system and surfaces behave similar to the calcium sulphate - stainless steel system studied in this work. Moreover, additional work should be undertaken to examine the effect of surface physical properties on crystal and bubble nucleation and growth.

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Ignatiev, Pavel. "Theoretical study of spin-polarized surface states on metal surfaces." kostenfrei, 2009. http://nbn-resolving.de/urn:nbn:de:gbv:3:4-688.

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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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Ramsvik, Trond. "Surface science studies of Cobalt and Rhodium single crystal surfaces." Doctoral thesis, Norwegian University of Science and Technology, Department of Physics, 2001. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2000.

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The main topic of this thesis is the investigation of small molecules adsorbed on the transition metals cobalt and rhodium surfaces by means of predominantly high-resolution core level photoemission and near edge x-ray absorption fine structure (NEXAFS). The thesis can be divided into three parts where the following phenomena are examined:

1) internal molecular vibrations in the core level photoemission spectra

2) hybridisation and thermal decomposition of adsorbates

3) growth and surface alloy formation of metal-on-metal systems

The influence on the C 1s spectra of photoemission induced internal vibrations after chemisorption is presented for two molecules, acetylene (C₂H₂) and carbonmonoxide (CO). In the former case the fine structure of the C-H vibrational stretch mode of acetylene on Co(0001) single crystal surface is resolved. The measured vibrational energy splitting is (389 ± 8) meV, which is ~6 % lower than what has been reported for gaseous acetylene. The corresponding Sfactor of 0.17 ± 0.02 is considerably higher than those reported for other systems. For CO molecules adsorbed on metal surfaces the C-O stretch vibration has a vibrational energy which is about half that of the C-H stretch in hydrocarbons. The progression of this vibrational mode for the systems CO/Co(0001), CO/Rh(100) and CO/Rh(111) have been thoroughly investigated. CO adsorbs in on-top sites on Co(0001) resulting in a vibrational splitting of (210 ± 3) meV from the adiabatic C 1s peak. For CO on Rh(100) two adsorption sites, on-top and bridge, are populated. Similar analyses of the vibrational fine structure gives a vibrational splitting of (221 ± 4) meV for on-top site and (174 ± 11) meV for bridge site. Investigations of the C-O vibrational properties on Rh(111), where CO populates on-top and three-fold hollow sites, show the same trend as for CO on Rh(100), namely decreasing vibrational splitting with increasing co-ordination. A tendency of increasing S-factor with increasing co-ordination is also reported.

Acetylene hybridisation and thermal decomposition on two crystal orientation of cobalt, Co(0001) and Co(1120) , have been investigated using a variety of experimental techniques: NEXAFS shows that acetylene chemisorb strongly to both cobalt surfaces. For the system C₂H₂/Co(0001) a state of hybridisation close to sp³ has been deduced, which is considerably stronger than what has been reported earlier. Photoemission spectroscopy measurements show that acetylene starts to decompose at a temperature ~100 K lower for Co(1120) compared to Co(0001). For the anisotropic Co(1120) surface the acetylene decomposition lead to formation of an ordered carbon overlayer. By combining these results with STM and LEED measurements a hard sphere model has been proposed for this overlayer.

Rare earth metals induce solid state reactions when thin overlayers are deposited onto a variety of metals and followed by annealing. Using high-resolution photoemission spectroscopy, LEED and temperature programmed desorption (TPD) a true surface alloy is shown to form with new electronic states when La on Rh(100) is annealed to 1350 K. These states alter the hybridisation of CO significantly compared to clean Rh(100) and as-deposited La on Rh(100). TPD experiments show CO desorption peaks at significantly lower temperature than CO on the as-deposited La/Rh(100), but still higher than the desorption peaks found for CO on Rh(100).

The homoepitaxial growth of cobalt on Co(1120) has been studied by STM. The diffusion of Co adatoms is found to be highly anisotropic with larger mobility of added Co atoms parallel than perpendicular to [0001], i.e. along the zigzag rows of the unreconstructed Co(1120) surface.

Papers are reprinted with kind permission of Elsevier, sciencedirect.com

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41

Berry, Elizabeth. "Fabrication of multiscale random rough surfaces with prescribed surface statistics." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/37944.

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Hao, Shuai. "An Introduction to Discrete Minimal Surfaces via the Enneper Surface." Thesis, Southern Illinois University at Edwardsville, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1543912.

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In this paper, we are exploring how to construct a discrete minimal surface. We map the conformal curvature lines of a parameterized continuous minimal surface to a unit sphere by the Gauss map. Then, based on a circle patterns we create, the Koebe polyhedron can be obtained. By dualizing the Koebe polyhedron, we are able to get the discrete minimal surface. Moreover, instead of only developing the method theoretically, we also show concrete procedures visually by Mathematica for Enneper with arbitrary domain. This is an expository project mainly based on the paper "Minimal surface from circle patterns: geometry from combinatorics" by Alexander I. Bobenko, Tim Hoffmann and Boris A. Springborn.

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Sharkey, Sarah Jane. "Laser surface engineering and process control for wear resistant surfaces." Thesis, University of Liverpool, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321167.

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Myshlyavtsev, Alexander V., and Marta D. Myshlyavtseva. "Modeling of surface diffusion for stepped surfaces: transfer matrix approach." Diffusion fundamentals 6 (2007) 27, S. 1-2, 2007. https://ul.qucosa.de/id/qucosa%3A14201.

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Thompson, Wade Raymond. "Surface Raman scattering of organically-modified metal and oxide surfaces." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186773.

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This research project was designed to investigate the surface chemistry of organosilanes at metal and oxide surfaces, specifically Ag, Au, SiO₂, and Al₂O₃. A combination of surface Raman spectroscopy, electrochemistry, scanning electron microscopy, x-ray photoelectron spectroscopy, and ellipsometry have been employed to study several important aspects of these films. Tetramethoxysilane (TMOS) and 1-propanethiol are used as models to provide detailed vibrational assignments for (3-mercaptopropyl)trimethoxysilane (3MPT). The vibrational assignments for 3MPT are used to assess the conformational order of 3MPT monolayers at Ag and Au surfaces before and after hydrolysis and condensation. Particular emphasis is given to the ν(Si-O), ν(C-H) modes, and the trans and gauche ν(C-S), ν(Si-C), and ν(C-C) modes in the frequency regions between ca. 500 to 1300 cm⁻¹ and ca. 2700 to 3000 cm⁻¹. The reactivity of the residual surface silanols and the wetting properties of the hydrolyzed 3MPT result in the surface acting as a modifying agent for the attachment of thin dielectric layers such as SiO₂ on Ag and Au surfaces. Adhesion of the thin SiO₂ films to the metal surfaces are characterized using standard qualitative and quantitative adhesion tests. Raman spectra of molecular assemblies of octadecylsilane layers, a model of reversed-phase liquid chromatographic stationary phase materials, are acquired using a thin silica gel/3MPT/Ag sandwich structure as the substrate. The Ag surface provides electromagnetic enhancement to the octadecylsilane overlayer. Spin coating a silica sol on the modified Ag surface results in the formation of a thin silica gel layer which contributes minimal fluorescence background to the Raman spectra. The spectra are interpreted in terms of the alkyl chain conformation on dry silica surfaces as well as in the presence of solvents commonly used in chromatography. The feasibility of acquiring Raman data from an Al/Al₂O₃ surface without an enhancing adlayer is demonstrated. Self-assembled films of octadecylsilane, octadecyldimethylsilane, and stearic acid were evaluated by Raman spectroscopy in terms of alkyl chain conformation. These data represent the first Raman spectra reported for alkylsilane layers on silica and Al₂O₃ surfaces without an enhancing adlayer and demonstrate the feasibility of acquiring conformational information from alkyl chains bound to oxide surfaces.

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Ugolini, Matteo. "K3 surfaces." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18774/.

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Bouix, Sylvain. "Medial surfaces." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19647.

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The medial surface of a 3D object is comprised of the locus of centers of its maximal inscribed spheres. Interest in this representation stems from a number of interesting properties: i) it is a thin set, i.e., it contains no interior points, ii) it is nomotopic to the original shape, iii) it is invariant under rigid transformations of the object and iv) given the radius of the maximal inscribed sphere associated which each skeletal point, the object can be reconstructed exactly. Hence, it provides a compact representation while preserving the object's genus and making certain useful properties explicit, such as its local width. These properties have led to its application in a variety of domains, including the analysis and quantification of the shape of volumetric structures in medical images. Despite its popularity, its numerical computation remains non-trivial. Most algorithms are not stable with respect to small perturbations of the boundary, and heuristic measures for simplification are often introduced. The study of the medial surface is the subject of this thesis.

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Sun, Amy (Amy Teh-Yu). "Programmable surfaces." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/70810.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 131-135).
Robotic vehicles walk on legs, roll on wheels, are pulled by tracks, pushed by propellers, lifted by wings, and steered by rudders. All of these systems share the common character of momentum transport across their surfaces. These existing approaches rely on bulk response among the fluids and solids. They are often not finely controllable and complex approaches suffer from manufacturing and practical operational challenges. In contrast I present a study of a dynamic, programmable interface between the surface and its surrounding fluids. This research explores a synthetic hydrodynamic regime, using a programmable surface to dynamically alter the flow around an object. Recent advances in distributed computing and communications, actuator integration and batch fabrication, make it feasible to create intelligent active surfaces, with significant implications for improving energy efficiency, recovering energy, introducing novel form factors and control laws, and reducing noise signatures. My approach applies ideas from programmable matter to surfaces rather than volumes. The project is based on covering surfaces with large arrays of small cells that can each compute, communicate, and generate shear or normal forces. The basic element is a cell that can be joined in arrays to tile a surface, each containing a processor, connections for power and communications, and means to control the local wall velocity The cell size is determined by the characteristic length scale of the flow field ranging from millimeters to centimeters to match the desired motion and fluidic system. Because boundary layer effects are significant across fluid states from aerodynamics to hydrodynamics to rheology, the possible implications of active control of the boundary layer are correspondingly far reaching, with applications from transportation to energy generation to building air handling. This thesis presents a feasibility study, evaluating current manufacturing, processing, materials, and technologies capabilities to realize programmable surfaces.
by Amy Sun.
Ph.D.

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Min, Hyerim Choi. "Encountered surfaces /." Online version of thesis, 1993. http://hdl.handle.net/1850/11971.

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Chaparro, Maria Guadalupe. "Minimal surfaces." CSUSB ScholarWorks, 2007. https://scholarworks.lib.csusb.edu/etd-project/3118.

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The focus of this project consists of investigating when a ruled surface is a minimal surface. A minimal surface is a surface with zero mean curvature. In this project the basic terminology of differential geometry will be discussed including examples where the terminology will be applied to the different subjects of differential geometry. In addition the focus will be on a classical theorem of minimal surfaces referred to as the Plateau's Problem.

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Dissertations / Theses on the topic 'Surfaces'

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