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1

Quist, Florence. "Crystallization of organic molecules onto functionalized surfaces." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66693.

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Crystallization of molecules is a well-known phenomenon and it plays an important role in various industrial domains, including pharmaceutical, yet it remains poorly understood. A particular problem which remains to be solved is the control of polymorphism. We took the approach of surface templated crystallization in order to get an increased understanding of selective polymorph growth processes. Three main parameters were chosen for investigation: the type of interactions between molecules in solution and interfaces, SAM packing and the introduction of a step within the SAM. To that end, a series of crystallization experiments were conducted on three types of interfaces: mono-component, bridged mono-component and bi-component. Introduction of the bridge allowed for modulation of the packing of molecules within the SAMs and insertion of a second component (phenylacetylene) with different backbone and size induced mismatch in interactions as well as formation of a step. Crystallization of two polymorphic model compound, octadecanol and 4-hydroxybiphenyl which present features commonly found in drug molecules, was first studied. Mono-component, bridged mono-component and bi-component SAMs that presented complementary features to the crystallizing molecule were constructed following an acid-base hydrolytic chemistry procedure previously developed in our lab. Characterization of the SAMs was done using ellipsometry, contact angle goniometry, FTIR-ATR and XPS. Presence of complementary features within the SAMs was found to promote crystal growth. For octadecanol, differences in SAM packing and composition were found to greatly influence crystallization outcome. In the case of 4-hydroxybiphenyl, crystallization experiments conducted on a bridged mono-component SAM induced the formation of a new monoclinic polymorph. Principles found in the study of model compounds were then applied to the crystallization of tw<br>La cristallisation des molécules est un phénomène très connu et joue un rôle important dans une grande variété de domaines industriels et notamment le domaine pharmaceutique. Ce phénomène demeure malheureusement fort peu compris. Un point particulier qui reste à élucider est celui du polymorphisme et surtout de son contrôle. Afin de mieux comprendre les mécanismes de sélection des polymorphes, nous avons utilisé des surfaces comme patrons lors d'expériences de cristallisation. Trois paramètres furent testés : l'importance du type d'interactions entre les molécules en solution et celles de l'interface, l'influence paquetage des monocouches auto-assemblées ainsi que l'introduction d'une aspérité dans la monocouche. Trois types de monocouches furent donc construits : des monocouches mono-composées, des monocouches mono-composées pontées ainsi que des monocouches bi-composées. L'introduction d'un pont lors de la formation de la monocouche a permis de moduler le paquetage de cette dernière et l'insertion d'un deuxième composé (le phénylacétylène) ne possédant pas la même ossature ni la même taille a permis d'induire un décalage dans les interactions ainsi que d'introduire une aspérité à la surface. La cristallisation de deux composés modèles, l'octadécanol et le 4-hydroxybiphenyl, a d'abord été réalisée. Ces deux composés ont été choisis car ils présentent des caractéristiques fréquemment retrouvées dans les molécules pharmaceutiques. Les trois types de monocouches présentant des caractéristiques complémentaires décrits précédemment ont été construits suivant une procédure impliquant une chimie acido-basique développée au sein de notre laboratoire. Ces monocouches ont été caractérisées par ellipsométrie, par mesure d'angle de contact, par spectroscopie FTIR-ATR et par XPS. Il a été observé que la présence de caractéristiques complémen
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2

Köhler, Mateus Henrique. "Water structure and dynamics through functionalized surfaces." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/179731.

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Neste trabalho propomos uma investigação através de simulações de dinâmica molecular da água em contato com superfícies hidrofóbicas e hidrofílicas, tanto dentro de nanotubos funcionalizados quanto em membranas bi-dimensionais para dessalinização. No caso da água em contato com superfícies hidrofóbicas e hidrofílicas de nanotubos nós encontramos uma quebra na relação de Stokes-Einstein para a difusão e a viscosidade da água. Essa quebra ocorre para os menores nanotubos − em que pelo menos duas camadas de água formam-se, condição para deslizamento de camadas necessária para o cálculo da viscosidade. O mecanismo por trás deste comportamento é ditado pela estrutura da água confinada. Esse resultado indica que algumas das características observadas para a água dentro de nanotubos hidrofóbicos, como nanotubos de carbono na natureza, são únicas. Encontramos uma grande dependência da dinâmica e estrutura da água confinada com as características polares do nanotubo, principalmente para nanotubos com diâmetros menores que 1 nm. Ao variarmos a temperatura do sistema, observamos ainda uma forte dependência da estruturação das moléculas de água com a temperatura, a ponto de apresentar transições entre estados mais e menos ocupados Nossos resultados de dinâmica molecular também mostram que membranas contendo nanoporos com sítios hidrofílicos entre regiões hidrofóbicas podem apresentar grande fluxo de água e reduzido transporte de íons, o que torna esses materiais excelentes candidatos para sistemas de dessalinização e limpeza de metais pesados. Ao acrescentarmos um químico floculante (cloreto de ferro) à água salgada, encontramos resultados ainda melhores para a rejeição de sal pelas membranas nanoporosas. Todos esses resultados demonstram a importância do estudo das propriedades hidrofóbicas e hidrofílicas em interfaces aquosas. Em todos os casos, encontramos uma dependência inerente das propriedades de transporte da água com a característica polar da superfície de contato.<br>In this work we have proposed an investigation through molecular dynamics (MD) simulations of the water behavior at hydrophobic and hydrophilic surfaces in both functionalyzed nanotubes and two-dimensional nanpores. In the case of water at hydrophobic and hydrophilic nanotube surfaces, we have found a breakdown of the Stokes-Einstein relation for diffusion and viscosity of water confined in narrow hydrophobic nanopores. The mechanism underlying this behavior is dictated by the structure of water under confinement. This result indicates that some of the features observed for water inside hydrophobic carbon nanotubes cannot be observed in other nanopores. We have also found an important dependence of the water dynamics with the polar character of the nanotube, mostly for small diameters. By varying the temperature, both the dynamics and the water structuration are affected, presenting transitions between dense-packed and low-density states. Our results also shows that nanoporous membranes, with hydrophilic sites sandwiched between hydrophobic regions, can present an important flux of water molecules and reduced ion transportation, making these structures promising for desalination processes. By adding a flocculant ingredient (ferric chloride) to the salt water, we found even larger ion rejection rates. All the results point out the importance of studying hydrophilic and hydrophobic interfaces for water transport. In all the cases, we have found an ubiquitous dependence of water dynamic properties on the surface polarity.
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3

Schieber, Romain. "Novel functionalized and patterned surfaces for cardiovascular applications." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/662854.

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Nowadays, cardiovascular diseases are mainly treated by implantation of a metallic or polymeric mesh, called stent, which maintains the artery widely open. This technique shows very good clinical results, however, it exists non negligible cases of in stent restenosis (ISR) and late stent thrombosis (LST) during the first year after stent implantation. These complications are mainly due to a delayed recovery of the endothelium after stent implantation, which also involves smooth muscle cells (SMCs) over-proliferation and platelet aggregation. Stent surface modification to modulate a specific cell lineage response has not been comprehensively explored. In particular, surface nano topography, biofunctionalization or chemical features may be applied to increase endothelial cells (ECs) adhesion and/or migration, and to control platelet agglomeration. The overall aim of this thesis was to obtain novel modified surfaces for stents implants with the ability to induce accelerated reendothelialization and controlled platelet aggregation in order to avoid ISR and LST. On CoCr alloy, as the gold standard material for bare metal stents (BMSs), two different strategies were evaluated, generation of linear patterns by direct laser interference patterning (DLIP) and, immobilization of biomolecules. On poly(L-lactic acid) (PLLA), as a material for bioresorbable stents (BRSs), endothelialization was enhanced by surface functionalization with NaOH etching, plasma treatment and cutinase enzyme hydrolysis. CoCr alloy surfaces were successfully modified with a linear pattern of different periodicities and depths. Afterwards, Arg-Gly-Asp (RGD) and Tyr Ile Gly Ser Arg (YIGSR) peptides were covalently immobilized to the surfaces through silanization. Early ECs adhesion was improved on the peptide functionalized surfaces, especially for YIGSR compared to RGD. High depth nano patterned surfaces generated ECs alignment within the topographical lines and enhanced EC migration. Noteworthy, the combined use of both strategies, topography and biofunctionalization, synergistically accelerated the ECs migration and proliferation. Also, platelet adhesion and aggregation decreased in all patterned surfaces compared to smooth CoCr probably due to changes in wettability and oxide layer characteristics. Cellular studies provided evidence of the potential of DLIP topographies and YIGSR biofunctionalization to foster endothelialization without enhancement of platelet adhesion, which will be of high importance when designing new stents. Concerning polymeric biodegradable materials, PLLA films were obtained by solvent casting in chloroform and, oxygen plasma, NaOH solution or cutinase enzyme treatments were used to functionalize the PLLA films and create surface hydroxyl and carboxyl groups without compromising biocompatibility. A higher amount of functional groups and an improved ECs adhesion was observed by oxygen plasma and cutinase enzyme hydrolysis compared to NaOH etching. Plasma or cutinase enzyme functionalized PLLA films presented a degradation rate similar to a peripheral commercial stent. Finally, 3D printed PLLA BRSs were obtained by solvent-cast direct write technique. Consequently, the combined use of the solvent cast direct write technique and plasma or enzyme functionalization holds a great potential to fabricate 3D printed PLLA BRSs with the capacity to accelerate the surface endothelialization. Overall, the present thesis offers a comprehensive view of the effectiveness of modifying CoCr alloy and PLLA films with specific topographies or functionalization strategies to enhance surface endothelialization while preventing restenosis and thrombosis.<br>Heutzutage werden vaskuläre Erkrankungen hauptsächlich durch Implantation eines metallischen oder polymeren Netzes, genannt Stent, behandelt, welcher vormals verengte Arterien weit geöffnet hält. Diese Technik zeigt bereits sehr gute klinische Ergebnisse. Allerdings existieren auch nicht zu vernachlässigende Fälle von In-Stent Restenose (ISR) und späten Stentthrombosen (LST) im ersten Jahr nach Implantation des Stents. Diese Komplikationen entstehen hauptsächlich aufgrund einer verzögerten Erholung der Endothele nach Einsetzen des Stents, sowie durch übermäßiges Wachstums der vaskulären glatten Muskelzellen (SMCs) und einer Thrombozytenaggregation. Modifikationen der Stent-Oberfläche, um die Interaktion mit spezifischen Zellypen zu kontrollieren, sind noch nicht umfassend erforscht. Insbesondere können Oberflächen-Nano-Topographie, Biofunktionalisierung oder chemische Modifizierungen angewendet werden, um die Adhäsion und / oder Migration der Endothelzellen (ECs) zu erhöhen und die Agglomeration von Blutplättchen niedrig zu halten. Das Gesamtziel dieser Arbeit war es, neuartige modifizierte Oberflächen für Stentimplantate zu entwickeln, die die Reendothelialisierung beschleunigen und eine Thrombozytenaggregation verringern, um ISR und LST vorzubeugen. Auf einer CoCr-Legierung, dem Gold-Standard-Material für unbeschichtete Metallstents (BMSs), wurden zwei unterschiedliche Strategien verfolgt; einerseits die Erzeugung linearer Muster durch direkte Laserinterferenzstrukturierung (DLIP) und Immobilisierung von Biomolekülen. Auf Poly (L-Milchsäure) (PLLA) als Material für bioresorbierbare Stents (BRSs) wurde die Endothelialisierung durch Oberflächenfunktionalisierung mit NaOH-Ätzen, mit einer Plasmabehandlung und mit Cutinase-Enzym-Hydrolyse verbessert. Zum anderen wurden Oberflächen einer CoCr-Legierung erfolgreich mit einem Linien-Muster unterschiedlicher Periodizität und Tiefe modifiziert. Anschließend wurden Arg-Gly-Asp (RGD) und Tyr-lle-Gly-Ser-Arg (YIGSR) Peptide durch Silanisierung kovalent an den Oberflächen immobilisiert. Die frühe ECs-Adhäsion wurde auf den Peptid-funktionalisierten Oberflächen verbessert, insbesondere für YIGSR im Vergleich zu RGD. Nanostrukturierte Oberflächen mit großer Tiefe erzeugten eine ECs-Ausrichtung innerhalb der topographischen Linien und förderten die EC-Migration und -Proliferation. Bemerkenswerterweise wurden diese synergetisch durch Kombination der zwei Strategien, Topographie und Biofunktionalisierung, beschleunigt. Auch die Thrombozytenadhäsion und –aggregation sanken in allen strukturierten Oberflächen verglichen mit glattem CoCr, möglicherweise auf Grund von Veränderungen der Benetzbarkeit und der Oxidschichteigenschaften. Zellstudien belegen das Potential von DLIP-Topographien und YIGSR-Biofunktionalisierung, um die Endothelialisierung ohne Erhöhung der Thrombozytenadhäsion zu fördern, was von großer Bedeutung bei der Entwicklung neuer Stents sein wird. In Bezug auf polymere biologisch abbaubaren Materialien wurden PLLA-Schichten durch Solvent-Casting in Chloroform hergestellt. Sauerstoffplasma, NaOh-Lösemittel oder Cutinase-Enzym-Behandlungen wurden genutzt, um die PLLA-Schichten zu funktionalisieren und Oberflächen-Hydroxylgruppen und -Carboxylgruppen herzustellen, ohne die Biokompatibilität zu beeinträchtigen. Im Vergleich zu NaOH-Ätzen wurden durch Sauerstoffplasma und durch Cutinase-Enzym-Hydrolyse eine höhere Anzahl an funktionellen Gruppen und eine verbesserte ECs-Adhäsion festgestellt. Plasma- oder Cutinase-Enzym-funktionalisierte PLLA-Schichten zeigten eine ähnliche Degradation wie ein peripher, kommerzieller Stent. Abschließend wurden 3D-gedruckte PLLA-BRSs durch Solvent-Cast Direct Writing hergestellt. Folglich bietet die Kombination aus Solvent-Cast Direct Writing und Plasma- oder Enzymfunktionalisierung ein großes Potenzial, 3D-gedruckte PLLA-BRSs mit beschleunigter Oberflächenendothelialisierung herzustellen. Insgesamt bietet die vorliegende Arbeit einen umfassenden Überblick über die Effektivität der Modifizierung von CoCr-Legierung und PLLA-Filmen mit spezifischen Topographien oder Funktionalisierungsstrategien zur Verbesserung der Oberflächenendothelialisierung bei gleichzeitiger Vermeidung von Restenose und Thrombose<br>Actualmente las enfermedades cardiovasculares están principalmente tratadas por implantación de una malla metálica o polimérica, llamada stent, que mantiene la arteria abierta. Esta técnica presenta muy buenos resultados clínicos, sin embargo, existen casos de reestenosis intra-stent (ISR) y trombosis tardia del stent (LST) durante el año que sigue la implantación. Estas complicaciones están principalmente debidas a una reparación demasiado lenta del endotelio después de la implantación del stent; que también implica una sobre-proliferación de células musculares lisas y una agregación de plaquetas. La modificación de la superficie del stent para generar una respuesta celular específica no ha sido explorada en profundidad. Particularmente, nano-topografía, biofuncionalización o modificaciones químicas pueden ser aplicadas para incrementar la adhesión y la migración de las células endoteliales (ECs), y para controlar la aglomeración de las plaquetas. El objetivo global de esta tesis es de obtener nuevas superficies modificadas para stent implantes con la habilidad de inducir una endotelización acelerada y de controlar la agregación de plaquetas. Sobre CoCr, material de referencia para los stent metálicos desnudos (BMSs), dos estrategias diferentes fueron evaluadas, la creación de patrones lineales por la técnica Direct Laser Interference Patterning (DLIP) y, la inmovilización de biomoléculas. Sobre acido L-poliláctico (PLLA), como material para stent biodegradables (BRSs), la endotelización fue activada por funcionalización de la superficie vía tratamientos con NaOH, plasma o enzima cutinasa. Patrones lineales de diferentes periodicidades y profundidades fueron obtenidos sobre superficies de CoCr. Después, los péptidos Arg-Gly-Asp (RGD) y Tyr-Ile-Gly-Ser-Arg (YIGSR) fueron enganchados covalentemente por silanización sobre les superficies de CoCr lisas y con patrones. La adhesión de ECs aumento sobre las superficies funcionalizadas, especialmente con el péptido YIGSR comparado con el RGD. Las superficies con patrones profundos generaron un alineamiento de las ECs con la dirección de las líneas del patrón y aceleraron la migración de esas mismas células. Además, el uso combinado de esas dos estrategias, topografía y biofuncionalización, acelero sinérgicamente la migración y la proliferación de las ECs. Por fin, la adhesión y la agregación de plaquetas disminuyo sobre todas las superficies con patrones comparado con las superficies de CoCr lisas, efecto causado por los cambios de la capa de óxido introducido por la técnica DLIP. Los estudios celulares demuestran el potencial de las topografías DLIP y de la biofuncionalización para mejorar la endotelización sin aumentar la adhesión de plaquetas, lo que puede ser interesante a la hora de diseñar nuevos stents. En cuanto a los stent biodegradables, películas de PLLA fueron obtenidas por la técnica de solvent-casting y, plasma de oxígeno, solución de NaOH o enzima cutinasa fueron utilizados para funcionalizar esas películas de PLLA y, así crear grupos hidroxilos y carboxilos en superficie sin comprometer la biocompatibilidad. Plasma de oxígeno y enzyma cutinasa generaron más grupos funcionales y mejoraron más la adhesión de ECs comparado con el tratamiento de NaOH. Además, las superficies de PLLA modificadas por plasma o enzima presentaron una degradación similar a la degradación de un stent comercial. Finalmente, BRSs de PLLA fueron obtenidos por impresión 3D vía la técnica de solvent-cast direct write. Consecuentemente, el uso combinado de esa técnica y de la funcionalización por plasma o enzima presenta un gran potencial para fabricar BRSs de PLLA impreso en 3D con la capacidad de acelerar la endotelización de la superficie. En conclusión, esta tesis demuestra la efectividad de modificar las superficies de CoCr o PLLA con topografías específicas o con estrategias de funcionalización para mejorar la endotelización y paralelamente reducir los riesgos de trombosis y reestenosis
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Castellanos, Arboleda Maria Isabel. "Functionalized CoCr surfaces with adhesive molecules to improve endothelialization." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/406352.

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Cobalt-chromium (CoCr) alloys are widely used as biomaterials for coronary stents due to their excellent mechanical properties, biocompatibility and corrosion resistance. However, these materials are bioinert, retarding the complete endothelialization and resulting in a higher risk of restenosis, narrowing of the artery, and late-stent thrombosis. Therefore, the improvement of implants surface endothelialization has acquired importance in the last years. Immobilization of cell adhesive biomolecules onto biomaterials surface is a well-known strategy to control cell response. However, the strategy of immobilization, the optimal combination or the appropriate spatial presentation of the bioactive sequences to enhance endothelialization for cardiovascular applications, remains to be elucidated. The present PhD thesis focused on the development of a new biofunctionalized CoCr alloy surfaces in order to improve the endothelialization. To that end, elastin-like recombinamers (ELR) genetically modified with an REDV (Arg-Glu-Asp-Val) sequence and short synthetized peptides RGDS (Arg-Gly-Asp-Ser), REDV, YIGSR (Tyr-Ile-Gly-Ser-Arg) and their equimolar combination, were attached by physisorption and covalent bonding onto CoCr alloy surfaces and thoroughly characterized physico-chemically and evaluated in vitro with human umbilical vein endothelial cells (HUVECs), coronary artery smooth muscle cells (CASMCs) and platelets from blood donors. First, biofunctionalized surfaces with ELR were developed and optimized by evaluating different surface activation treatments, oxygen plasma and sodium hydroxide etching, and different binding strategies, physisorption and covalent bonding. The functionalized surfaces demonstrated a higher cell adhesion and spreading of HUVEC cells, this effect is emphasized as increases the amount of immobilized biomolecules and directly related to the immobilization technique: covalent bonding. Nevertheless, the silanization process was not completely effective since a mixture of covalent and physisorption behavior was observed probably due to the use of big molecules that decreased the control of the bonding between the biomolecule and the surface. Secondly, it was synthetized immobilized RGDS, REDV, YIGSR and their equimolar combination peptides onto the different surfaces. Cell studies demonstrated that the covalent functionalization of CoCr surfaces with an equimolar combination of RGDS/YIGSR represented the most powerful strategy to enhance the early stages of HUVECs adhesion, proliferation and migration, indicating a positive synergistic effect between the two peptide motifs. Besides, gene expression and platelet adhesion studies showed that surfaces silanized with the combination RGDS/YIGSR improved anti-thrombogenicity compared to non-modified surfaces. Finally, cell co-cultures of HUVECs/CASMCs found that functionalization increased the amount of adhered HUVECs onto modified surfaces compared to plain CoCr, independently of the used peptide and the strategy of immobilization. Overall, the present thesis offer a comprehensive view of the effectiveness of immobilizing cell adhesive molecules onto CoCr alloy surfaces to enhance endothelialization while preventing restenosis and thrombosis for cardiovascular applications.<br>Las aleaciones de cobalto-cromo (CoCr) son ampliamente utilizadas como biomateriales para stents coronarios debido a sus excelentes propiedades mecánicas, biocompatibilidad y resistencia a la corrosión. Sin embargo, estos materiales son bio-inertales, retardando la completa endotelialización y resultando en un mayor riesgo de reestenosis, estrechamiento de la arteria y trombosis tardía. Por lo tanto, la mejora de la endotelización de superficie de los implantes ha adquirido importancia en los últimos años. La inmovilización de biomoléculas adhesivas celulares sobre la superficie de los biomateriales es una estrategia bien conocida para controlar la respuesta celular. Sin embargo, queda por aclararse la estrategia de inmovilización, la combinación óptima o la presentación espacial apropiada de las secuencias bioactivas para potenciar la endotelización en aplicaciones cardiovasculares. La presente tesis doctoral se centró en el desarrollo de una nueva superficie biofuncionalizada de la aleación CoCr con el fin de mejorar la endotelialización. Para ello, los recombinameros tipo elastina (ELR) modificados genéticamente con una secuencia REDV (Arg-Glu-Asp-Val) y péptidos cortos sintetizados RGDS (Arg-Gly-Asp-Ser), REDV, YIGSR (Tyr-Ile-Gly -Ser-Arg) y su combinación equimolar, fueron anclados por fisisorción y unión covalente a las superficies de la aleación, se caracterizaron físicamente-químicamente y evaluó in vitro con células endoteliales de vena umbilical humana (HUVECs), células de músculo liso de arteria coronaria (CASMCs) y plaquetas de donantes de sangre. En primer lugar, se desarrollaron y optimizaron las superficies biofuncionalizadas con ELR mediante la evaluación de diferentes tratamientos de activación superficial: plasma de oxígeno y ataque con hidróxido de sodio, y diferentes estrategias de unión: fisisorción y unión covalente. Las superficies funcionalizadas demostraron una mayor adhesión celular y propagación de células HUVEC, este efecto se enfatiza a medida que aumenta la cantidad de biomoléculas inmovilizadas y se relaciona directamente con la técnica de inmovilización: la unión covalente. Sin embargo, el proceso de silanización no fue completamente efectivo, ya que se observó una mezcla de uniones covalentes y fisisorbidas, probablemente debido al uso de grandes moléculas que disminuyeron el control de la unión entre la biomolécula y la superficie. En segundo lugar, se inmovilizado los péptidos sintetizados RGDS, REDV, YIGSR y sus combinaciones equimolares sobre las diferentes superficies. Los estudios celulares demostraron que la funcionalización covalente de las superficies de CoCr con una combinación equimolar de RGDS/YIGSR representó la estrategia más potente para potenciar las etapas tempranas de la adhesión, proliferación y migración de HUVECs, indicando un efecto sinérgico positivo entre los dos motivos peptídicos. Además, la expresión génica y los estudios de adhesión plaquetaria mostraron que las superficies silanizadas con la combinación RGDS/YIGSR mejoraron la antitrombogenicidad en comparación con las superficies no modificadas. Finalmente, con los co-cultivos celulares de HUVECs/CASMCs se encontró que la funcionalización aumentaba la cantidad de HUVEC adheridas sobre las superficies modificadas en comparación con CoCr simple, independientemente del péptido usado y la estrategia de inmovilización. En general, la presente tesis ofrece una visión completa de la efectividad de la inmovilización de moléculas adhesivas celulares en la superficie de la aleación CoCr para mejorar la endotelialización, mientras que previene la reestenosis y trombosis en aplicaciones cardiovasculares.
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Rutenberg, Isaac Michael Goddard William A. "Functionalized polymers and surfaces via ring-opening metathesis polymerization /." Diss., Pasadena, Calif. : California Institute of Technology, 2005. http://resolver.caltech.edu/CaltechETD:etd-08132004-132724.

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Wiley, Devon S. "Oxide Nanofilms from Nanoparticle Suspensions Deposited on Functionalized Surfaces." Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1217022473.

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Plachinda, Pavel. "Electronic Properties and Structure of Functionalized Graphene." PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/585.

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The trend over the last 50 years of down-scaling the silicon transistor to achieve faster computations has led to doubling of the number of transistors and computation speed over about every two years. However, this trend cannot be maintained due to the fundamental limitations of silicon as the main material for the semiconducting industry. Therefore, there is an active search for exploration of alternate materials. Among the possible candidates that can may [sic] be able to replace silicon is graphene which has recently gained the most attention. Unique properties of graphene include exceedingly high carrier mobility, tunable band gap, huge optical density of a monolayer, anomalous quantum Hall effect, and many others. To be suitable for microelectronic applications the material should be semiconductive, i.e. have a non-zero band gap. Pristine graphene is a semimetal, but by the virtue of doping the graphene surface with different molecules and radicals a band gap can be opened. Because the electronic properties of all materials are intimately related to their atomic structure, characterization of molecular and electronic structure of functionalizing groups is of high interest. The ab-inito (from the first principles) calculations provide a unique opportunity to study the influence of the dopants and thus allow exploration of the physical phenomena in functionalized graphene structures. This ability paves the road to probe the properties based on the intuitive structural information only. A great advantage of this approach lies in the opportunity for quick screening of various atomic structures. We conducted a series of ab-inito investigations of graphene functionalized with covalently and hapticly bound groups, and demonstrated possible practical usage of functionalized graphene for microelectronic and optical applications. This investigation showed that it is possible [to] produce band gaps in graphene (i.e., produce semiconducting graphene) of about 1 eV, without degrading the carrier mobility. This was archived by considering the influence of those adducts on electronic band structure and conductivity properties.
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Blaudeck, Thomas. "Self-Assembly of Functionalized Porphyrin Molecules on Semiconductor Nanocrystal Surfaces." Doctoral thesis, Universitätsbibliothek Chemnitz, 2007. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200701451.

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Im Fokus dieser Dissertation stehen anorganisch-organische Hybridaggregate aus Kadmiumselenid-Nanokristallen und funktionalisierten Porphyrinmolekülen in Lösung. Mit Hilfe von statischen und zeitaufgelösten Methoden der optischen Spektroskopie wird nachgewiesen, daß die Bildung der Aggregate durch spontane Adsorption der funktionalisierten Moleküle an der Nanokristalloberfläche erfolgt. Dabei ist von einem dynamischen Gleichgewicht zwischen den Porphyrinmolekülen und den ursprünglichen Nanokristall-Liganden (TOPO) auszugehen. In der Photophysik der Hybridaggregate lassen sich ein resonanter Energietransfer nach Förster, der vom Nanokristall zum Porphyrinmolekül gerichtet ist, sowie eine Elektronen-Austauschwechselwirkung zwischen beiden Komponenten nach Dexter nachweisen. Mit Hilfe einer Erweiterung des Stern-Volmer-Ansatzes zur Beschreibung der Fluoreszenzlöschung für bimolekulare Reaktionen können die jeweiligen Anteile für eine Serie von Nanokristallen unterschiedlicher Größe und zweierlei Beschaffenheit grob quantifiziert werden. Ferner wird der Einfluß diffundierender Ladungen auf die Quantenausbeute von Halbleiternanokristallen anhand von zeitkorrelierter Einzelphotonenerfassung untersucht. Mit Hilfe einer Detektionsmethode, die die Zeitreihe der Ankunftszeiten einzelner Photonen erhält (tt-TCSPC), ist es möglich, den in eine Polymermatrix eingebetteten Halbleiternanokristallen charakteristische Fluktuationen der Fluoreszenzlebensdauer mit individueller Zeitkonstante zuzuordnen<br>This Thesis is devoted to the formation and the photophysics of inorganic/organic hybride nanoaggregates designed from CdSe semiconductor nanocrystals and pyridyl-functionalized porphyrin molecules in solution at ambient conditions. The formation of the aggregates is revealed to be based on a spontaneous adsorption of the functionalized porphyrin molecules on the nanocrystal surfaces, with a dynamic equilibrium sustained due to the competition with TOPO, ie. the original surface ligand. The evidence for the existence of the self-assembled aggregates is furnished by the proof of a directed Förster resonant energy transfer from the nanocrystal to the porphyrin molecules at low compound concentrations. By means of steady-state and time-resolved optical spectroscopy, the resonant energy transfer (RET) is valued to be accompanied by at least one more secondary quenching mechanism. Motivated by the aptitude of the nanocrystals to host more than one molecule at once, the detection and quantification of this process is done by an extension of the conventional Stern-Volmer kinetics valid for bimolecular reactions. With that, the secondary interaction process aside from RET is explained in terms of a Dexter-type energy transfer that, on ist part, can be put down to a generation of charge-induced shallow trap states within the semiconductor nanocrystal. This model is in qualitative accordance with the known phenomena of fluorescence intermittency and spectral diffusion. The role of a fluctuating environment to affect the fluorescence quantum yield of the nanocrystals is confirmed by time-tagged time-correlated single-photon counting (tt-TCSPC) on single nanocrystals in a polymer matrix. The measurements show that the fluorescence lifetime of the nanocrystals is characterized by individual characteristic fluctuations possibly induced by temporal and spatial inhomogeneities in the distribution of the dielectric constants
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9

Lee, Chi-Ying. "Characterization of DNA-functionalized surfaces for microarray and biosensor applications /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/9915.

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10

Biyikli, Kasim. "Nucleation and growth of crystals of pharmaceuticals on functionalized surfaces." Worcester, Mass. : Worcester Polytechnic Institute, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-020606-165721/.

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11

Gnad, Christoph [Verfasser]. "Molecular Palladium Catalysts Supported on Functionalized Oxide Surfaces / Christoph Gnad." München : Verlag Dr. Hut, 2019. http://d-nb.info/1196415757/34.

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12

Mittal, Sukant. "Antibody-functionalized nanoporous surfaces enable high throughput specific cell capture." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/72913.

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Thesis (Ph. D. in Medical and Electrical Engineering)--Harvard-MIT Program in Health Sciences and Technology, 2012.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 108-114).<br>Adhesion-based cell capture on surfaces in microfluidic devices forms the basis of numerous biomedical diagnostics and in vitro assays. Solid surface microfluidic platforms have been widely explored for biomedical diagnostics since samples can be precisely and reproducibly manipulated under well-defined physicochemical conditions. However, at these small length scales, the fluid dynamics are dominated by the high surface-to-volume ratio and interfacial phenomena limiting device performance at high flow rates. In contrast, cell homing to porous vasculature is highly effective in vivo during inflammation; stem cell trafficking and cancer metastasis. In this work, we demonstrate that fluid-permeable surface functionalized with cell-specific antibodies can promote efficient and selective cell capture in vitro. This architecture might be advantageous due to enhanced transport due to fluid field modification leading to diverted streamlines towards the surface. Moreover, specific cell-surface interactions can be promoted due to reduced shear, allowing gentle cell rolling and arrest. Together, these synergistic effects enable highly effective target cell capture at flow rates over an order of magnitude larger than existing devices with solid surfaces. Additionally, in this study, we overcome a major limitation relevant to porous surfaces due to formation of stagnant layers of cells from non-target background population. These stagnant layers are detrimental to device performance as they act to reduce interaction of the cells with the reactive surface thereby reducing capture efficiency. We theoretically and experimentally understand the mechanisms for formation of the stagnant bioparticle layer in microfluidic devices and define a parameter space for optimal operation of the device over long periods of time. Key insights from these studies, collectively allow us to design a spatially modified microfluidic devices that allow us to isolate cancer lines as low as 5 cells/mL spiked into buffy coat.<br>by Sukant Mittal.<br>Ph.D.in Medical and Electrical Engineering
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13

Yuan, Hongye. "Growth of Metal Organic Frameworks (MOFs) layers on functionalized surfaces." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLX058/document.

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Dans ce travail, nous étudions les conditions de synthèse pour la croissance directe des MOF Fe3 + / H2BDC et Fe3 + / H2NDC sur des surfaces de silicium fonctionnalisées (111) présentant une structure bien définie et dont la chimie de surface peut être adaptée pour favoriser / diriger la nucléation et la croissance hétérogènes Des MOF. Le mécanisme de croissance des MOF pertinents aux conditions choisies et les propriétés flexibles des cadres MIL-88B et MIL-88C sont également présentés avec l'aide des résultats du traitement post-synthèse.En ce qui concerne le système de morphologies et structures Fe3 + / H2BDC, les structures des couches obtenues dépendent fortement de la chimie de surface des monocouches greffées et aussi des conditions de synthèse (température, composition de la solution et temps de réaction). Les cristaux MIL-88B orientés sur la direction [001] sont seulement observés sur des surfaces fonctionnalisées par COOH et se sont révélés être favorisés en présence d'un excès de ligand en solution. La formation de la phase MIL-101 texturée le long de la direction [111] sur les surfaces de Si pyridyl et hydroxy-terminé est observée indépendamment de la condition de synthèse. Des cristaux MIL-101 isolés avec une orientation préférée le long de la direction [111] ont également été trouvés sur une surface terminée par acide à un excès de métal, alors que les îlots MIL-101 orientés au hasard sont observés au rapport R ≧ 1. Au contraire, aucune croissance du film ne s'est produite sur les surfaces de Si à terminaison méthyle. L'introduction de HCl, de H2O et de base faible organique -triéthylamine dans les solutions précurseurs affecte également la formation de films MOF avec différentes morphologies et couverture entre MIL-101 et MIL-88B sur des surfaces de Si à terminaison carboxylique. La dépendance temporelle de la croissance du film à un excès de ligand (R = 2) et d'un excès de métal (R = 0,5) sans et avec addition de HCl indique clairement que les deux MIL-88B et MIL-101 suivent un mode de croissance Volmer-Weber, Au cours de laquelle, des cristaux ou des grappes tridimensionnels isolés se sont formés à l'étape initiale et se sont développés latéralement et verticalement à la surface.En ce qui concerne le système de Fe3 + / H2NDC, en fonction des conditions de synthèse, y compris la température, le rapport du ligand à la concentration [Fe3 +] et [Fe3 +] seulement une phase-MIL-88C avec une couverture de surface variable allant des cristaux hexagonaux séparés aux couches composées d'isolés On a observé des faisceaux de cristallites hexagonales tous avec une orientation préférentielle le long de la direction. L'évolution des cristaux de MIL-88C avec le temps de cristallisation suggère également un mode Volmer-Weber.Les mesures ex-situ XRD du post-traitement vers les couches synthétisées constituées de MIL-88B et MIL-88C démontrent respectivement leur flexibilité lors de la désorption des molécules. Les mesures provisoires de la XRD in situ montrent également la réversibilité du cadre MIL-88C lors de l'absorption et de la libération de l'éthanol<br>Within this work we investigate synthesis conditions for the direct growth of Fe3+/H2BDC and Fe3+/H2NDC MOFs onto functionalized silicon (111) surfaces exhibiting well-defined structure and whose surface chemistry can be tailored in order to favor/direct the heterogeneous nucleation and growth of the MOFs. Growth mechanism of relevant MOFs at chosen conditions and flexible properties of MIL-88B and MIL-88C frameworks are presented as well with the assistance of post-synthesis treatment results.Regarding the system of Fe3+/H2BDC morphologies and structures of obtained layers strongly depend both on surface chemistry of grafted monolayers and also on the synthesis conditions (temperature, solution composition and reaction time). Oriented MIL-88B crystals along [001] direction is only observed onto COOH-functionalized surfaces and was found to be favored in presence of ligand excess in solution. The formation of textured MIL-101 phase along [111] direction on pyridyl and hydroxyl terminated Si surfaces is observed irrespective of the synthesis condition. Isolated MIL-101crystals with preferred orientation along [111] direction was also found on acid terminated surface at excess of metal, whereas randomly oriented MIL-101 islands are observed at ratio R≧1. In contrary, no film growth happened on methyl terminated Si surfaces. Introduction of HCl, H2O and organic weak base-triethylamine into the precursor solutions also affects the formation of MOF films with various morphologies and coverage between MIL-101 and MIL-88B on carboxylic terminated Si surfaces. Time dependence of film growth at excess of ligand (R=2) and at excess of metal (R=0.5) without and with addition of HCl indicates clearly that both of MIL-88B and MIL-101 follows a Volmer-Weber growth mode, during which, isolated three-dimensional crystals or clusters formed at initial stage and grew both laterally and vertically on the surface.As to the system of Fe3+/H2NDC, depending on the synthesis conditions including temperature, ratio of ligand to [Fe3+] and [Fe3+] concentration only one phase-MIL-88C with variable surface coverage ranging from separated hexagonal crystals to layers composed of isolated bundles of hexagonal crystallites all with preferential orientation along [001] direction was observed. Evolution of MIL-88C crystals along with crystallization time also suggests a Volmer-Weber mode.Ex-situ XRD measurements of post-treatment towards the as-synthesized layers comprised of MIL-88B and MIL-88C respectively demonstrate their flexibility during molecule desorption. Tentative in-situ XRD measurements also show the reversibility of MIL-88C framework upon ethanol uptake and release
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Stoianov, Stefan Vladimirov. "Properties modification of nanopatterned surfaces functionalized with photo activated ligands." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/40434.

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This dissertation focuses on four research topics: self-assembly of colloidal nanoparticles, surface modifications of the properties of ionically self-assembled multilayer films, surface enhanced Raman spectroscopy of functionalized gold nanoparticles, and two photon uncaging in gel. Those techniques are used for development of novel nanofabrication methods for top-down and bottom-up assembly of nanostructures, by modifying the properties of nanopatterned surfaces with photoactive ligands, and other technologies. First I describe the development of an improved method for nanosphere lithography, a variation of the convective self-assembly technique. The method exhibited high reproducibility and yielded high quality monolayer crystals by withdrawing a meniscus of liquid polystyrene spheres solution and subsequent evaporation of the solvent. The monolayer crystal was used as an evaporation mask to create surface arrays of gold nanotriangular particles. Metal nanoparticles, with sharp features or narrow gaps, exhibit strong plasmonic properties. I took advantage of those properties to attempt to create patchy modifications of the surface functionalization of gold nanotriangular particles treated with photosensitive molecules. Two molecules denoted, P3-DTC, and LIP3, were used as functional molecules attached to the gold nanoparticles. After interaction with 356nm UV light, part of those molecules cleaves off the surface of the nanoparticles rendering the surface modified with a new functional group. The modification takes place only at the plasmonic hot spots of those nanoparticles, resulting in a patchy modification of the properties of the nanoparticles. I built polymer Ionically Self-assembled Multilayer (ISAM) films using a Layer-by-Layer deposition technique and treated them to alter their surface adhesion properties. Poly (allylamine hydrochloride) (PAH), and poly (styrene sulfonate) (PSS) are a very well-studied system of polyelectrolytes for LbL deposition. ISAM films built from those polyelectrolytes are rich in amine groups to which nanoparticles, cells, tissue cultures, ligands can be made to adhere. In my work I developed a method for selective modification of the surface adhesiveness, by neutralizing the amine groups trough acetylation with acetic anhydride. With resolution from a few microns to a few hundred nanometers, I selectively passivated some areas of the ISAM film while others I left unaltered. I tested the effect of the acetic anhydride passivation by performing Horse Radish Peroxidase (HRP) test which quantifies the amount of free amines on the surface of the film. I also demonstrated the patchy modification of surface adhesiveness by introducing gold nanospheres which attached only to the amine active areas of the modified ISAM film. Photoactivatable fluorophores, i.e. compounds and other entities that may transform into a fluorescent form on absorption of a photon can be employed in multidimetional volume patterning. I studied the photoactivation of aryl azides in gelatin matrix. Specifically, I used Azidocoumarin 151 as a test molecule to undergo two-photon activation, and then measured the resulting photoluminescence. The activation of the Azidocoumarin 151 can be used to create arbitrary 3D patterns of modified functionality inside the gel. The activated molecules can be used as sites for further modification of the patterning inside the volume of the gel. Possible modifications include attaching biomolecules, nanoparticles, or individual cells. Acknowledgements I would like to acknowledge my adviser Hans Robinson for giving me the opportunity to work on several very interesting projects. Dr. Robinson has thought me critical thinking and supported greatly my research in his laboratory. He was always kind and willing to discuss scientific ideas and therefore contributed to my development as a successful graduate student. Iâ d like to also thank Dr. Richie Davis and Dr. Webster Santons for the useful discussions about my projects. I had the great pleasure to work closely with several graduate students during my time at Virginia Tech. Kai Chen, helped me get into the field of polymer self assembled films. I worked closely with Jason Ridley on modifying surface properties of ISAM films. Brandon Thorpe has been a constant supplier of a variety of compounds that I used in my SERS studies. Iâ d like to thank my fellow graduate students from Dr. Robinsonâ s group, Chih-Yu Jao, Eric See, Kirby Mayers, for being great company and lending help when I need it. During my stay at Virginia Tech I have met some wonderful faculty and staff at the Department of Physics. They were all very helpful, but Iâ d like to extend special thanks to Chris Thomas, Dr. Ghiti Khodaparast, Dr. Mark Pitt, Dr. Tetsuro Mizutani, and Randy Heflin. Finally, Iâ d like to thank my wife Elitsa for being patient during my time as a graduate student. Iâ d like to also thank my daughter Eleonora and son Alexander for being the cutest kids in the world and for cheering me up all the time.<br>Ph. D.
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15

Vahlberg, Cecilia. "Structure analysis and molecular recognition studies of bio-functionalized surfaces." Doctoral thesis, Linköpings universitet, Molekylär ytfysik och nanovetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71457.

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Biological and chemical reactions involved in physiological processes are often complex and very sophisticated. Such processes can be mimicked in the laboratory to obtain important knowledge, valuable for the  development of new diagnostic methods, drugs and biosensors. This  thesis includes investigations of bio-functionalized surfaces that can be used as model systems to mimic naturally existing biomolecular recognition processes. In this thesis, three different peptides, of our own design, that mimic parts of the second and third intracellular loops of the α2A-adrenergic receptor, are studied. The peptides were immobilized onto gold substrates, through thiol chemistry. The interaction between the peptides and the G-protein was investigated using surface plasmon resonance (SPR). The G-protein showed the highest binding capability for surfaces functionalized with a peptide mimicking the n-terminal of the third intracellular loop (GPR-i3n). The binding was enhanced when the pure GPR-i3n peptide was mixed with a short oligopeptide (3GC). A tentative explanation for the obtained results is that the presence of the 3GC molecule enables conformational changes of the GPR-i3n monolayer which affect the interaction with the G-protein. The results from the SPR measurements also indicated that the conformation of the G-protein was kept intact during the interaction with a peptide mimicking the c-terminal of the third intracellular loop (GPR-i3c). Multilayers were formed on the surfaces functionalized with a peptide mimicking the second intracellular loop (GPR-i2c) and the GPR-i3n peptide. We suggest that conformational changes of the G-protein are induced during the interaction with the surfaces functionalized with the GPR-i3n and GPR-i2c peptides. Comprehensive surface characterizations of four biomolecular systems, based upon the functional groups: noradrenaline, phenylboronic-ester, phenylboronic-acid and benzenesulfonamide, are presented in the thesis. The aim is to develop a platform for detailed molecular recognition studies on surfaces. The molecular systems were characterized using infrared spectroscopy, X-ray photoelectron spectroscopy, near edge X-ray absorption fine structure spectroscopy, ellipsometry and contact angle goniometry. Noradrenaline was chosen as it is a neurotransmitter that interacts with the extracellular loops of adrenergic receptors. In this work, the noradrenaline analogue (Nor-Pt) of our own design, was equipped with a -SH handle to be linked to surfaces and with the free noradrenaline group available for interaction studies. The Nor-Pt molecules were organized on the surfaces with the sulfur atom close to the gold substrate and the aromatic ring available for possible interactions with other biomolecules in the ambient media. The main component of the C=O vibrational mode present in the amide moiety had a parallel orientation relative to the plane of the gold surface, based on the infrared spectroscopy results. The phenylboronic system was designed as a simple mimicry of an  adrenergic receptor as the boronic acid functional group binds to diol containing molecules such as noradrenaline. The boronic  esterterminated alkane thiol (BOR-Capped) was chemisorbed onto gold substrates. We showed that BOR-Capped was linked to the gold substrate via thiolate bond formation and formed a well-organized monolayer. The pinacolyl protection group was removed directly from the BOR-Capped monolayer on the surfaces, which resulted in an unprotected monolayer terminated with the boronic acid functional group (BOR-Uncapped). The strong chemical bond to the gold substrate was retained during the deprotection procedure as only thiolate sulfur species were observed for the BOR-Uncapped molecular system. The benzenesulfonamide based molecule was designed as a model system for bioselective surfaces. An amine-terminated alkane thiol was adsorbed onto a gold substrate. In a second step, a benzenesulfonamide derivative was linked to the amine-terminated monolayer by the formation of an amide bond. We showed that the resulting benzenesulfonamide-terminated alkane thiol (AUT-C6) formed a well-organized and semi-thick monolayer on the gold substrate. The polarization dependence of NEXAFS was used to determine the average tilt angle of the aromatic ring structures of Nor-Pt, BOR-Capped, BOR-Uncapped and AUT-C6. The results indicate that the aromatic ring planes of BOR-Capped and AUT-C6 have a preferential orientation toward the surface normal. The aromatic ring structures of Nor-Pt and BOR-Uncapped were determined to have a more tilted orientation relative to the gold surface normal. Finally, the interaction between carbonic anhydrase and the AUT-C6 molecule was investigated using surface plasmon resonance and ellipsometry. The surface immobilized benzenesulfonamide was shown to bind to carbonic anhydrase and the results indicated that the interaction is specific.
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16

Jalkh, Joanna. "Engineering of functionalized monolayers for molecular electronics." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S153.

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La modification des surfaces revêt un intérêt primordial dans de nombreux champs d'applications de la chimie, comme la chimie analytique et l'électronique moléculaire. Ce travail a porté sur l'étude de différentes monocouches liées de façon covalente à des surfaces conductrices (principalement le carbone) et préparées à partir de l'électroréduction de sels d'aryldiazonium. Ces monocouches organiques ont été fonctionnalisées avec des groupements terminaux électroactifs différents, et l'on s'est intéressé aux propriétés de transfert de charge (au sens large) des couches résultantes. Tout d'abord des couches portant un système redox simple à base de ferrocène ont été étudiées dans différents milieux organiques conventionnels et en milieu liquides ioniques. L'effet de l'éloignement du système redox vis-à-vis de la surface a été également analysé en variant la longueur du pont ancrant. Dans un second temps, les monocouches organiques ont été fonctionnalisées par des unités tétrathiafulvalène (TTF). Les TTF sont des molécules (donneur d'électrons) connues pour former des complexes à transfert de charge avec le tétracyanoquinodiméthane (TCNQ), accepteur d'électrons. La formation de complexes à transfert de charge entre des TTF immobilisées dans la monocouche et des dérivés TCNQ a été étudiée et modulée selon l'éloignement du TTF vis-à-vis de la surface (variation de la longueur du lien ancrant) et en fonction de la force de l'accepteur. Enfin, des monocouches avec des groupements terminaux de type fluorène ou spirobifluorène (SBF) ont été préparées. Le comportement bloquant vis-à-vis-du transfert d'électron a été étudié par microscopie électrochimique (SECM) en présence de deux médiateurs redox différents et la conductivité des couches a été évaluée par CP-AFM (microscopie à force atomique – mesure de courants locaux). Il est montré que les propriétés de transfert/transport de charges sont influencées par l'encombrement stérique associé au fluorène ou au SBF (variation de la substitution). Ces monocouches organiques stables, bien organisées apparaissent très prometteuses comme composants dans des dispositifs d'électronique moléculaire<br>Surface modification is of paramount importance in many fields of chemistry like analytical chemistry and molecular electronics. This work deals with the study of different monolayers covalently bound on conducting (mainly carbon) surfaces, and produced from the electroreduction of aryldiazonium salts. By introducing electroactive components in the resulting monolayers, the different studies in this work mainly focused on charge-transfer properties (in a large sense). First, monolayers bearing simple redox-active ferrocenyl terminal groups were investigated. The electrochemical behavior of these monolayers was analyzed in different conventional organic media and in ionic liquids (RTILs) and by varying the length of the bridging unit between the surface and the ferrocene groups. Second, redox-active tetrathiafulvalene (TTF) molecules were used to functionalize the monolayers. TTF molecules are well-known donor molecules able to form charge-transfer complexes with tetracyanoquinodimethane (TCNQ) as an electron-acceptor. The formation of charge-transfer complexes between immobilized TTF and TCNQ derivatives was studied and modulated by varying the chain length of the bridging unit between the TTF donor and the surface and by varying the electron-withdrawing ability of the TCNQ acceptors. Third, monolayers with fluorene and spirobifluorene (SBF) terminal groups were prepared. The blocking behavior towards electron transfer was studied by electrochemical microscopy (SECM) with two redox mediators and the conductivity of the layers was investigated by CP-AFM (Conducting Probe-Atomic Force Microscopy). Effects due to the steric hindrance of the fluorene or SBF derivatives were evidenced. Such stable, organized and organic monolayers seem to be promising candidates for molecular electronic devices
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17

Wittke, Ralph Harald. "Darstellung und Untersuchung funktionalisierter Polymeroberflächen / Creating and testing functionalized polymer surfaces." Gerhard-Mercator-Universitaet Duisburg, 2005. http://www.ub.uni-duisburg.de/ETD-db/theses/available/duett-09092005-171021/.

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Different polymers were used as antimicrobial finishing agent in textile application. Different methods were used to functionalize polyvinylamine, chitosan and cylcodextrin onto fibres. The finished fabrics were chracterized by different analytical tools. In addition the antibacterial activity of the modified surfaces was evaluated by Tetrazolium-Formazan test. A surface test agent (Toluol) was complexed by ß-Cyclodextrin and its deliverey was evaluated by olfactometry.
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18

Oquendo, Galarza Luis E. "Modification of Indium Tin Oxide Surfaces with Phosphonic Acid Functionalized Phthalocyanines." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/344225.

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The overall efficiency of organic photovoltaics cells (OPVs) is influenced by the nature of the charge injection barrier at the transparent conducting oxide (TCO) bottom contact. Modification of the transparent conducting oxide (TCO)/organic interface with an electroactive molecular monolayer will potentially create a robust ohmic contact that will influence the efficiency of hole injection into the TCO. Asymmetric zinc Phthalocyanines (ZnPc) with a flexible phosphonic acid (PA) linker have been synthesized and used to modify indium tin oxide (ITO) surfaces. The adsorption of PA functionalized asymmetric ZnPcs on an ITO/waveguide was monitored using attenuated total reflectance (ATR) spectroscopy. Polarized dependent ATR spectroscopy was used to determine the orientation of these absorbed subpopulations species on ITO modified surfaces as a function of wavelength using transverse electric (TE) or transverse magnetic (TM) polarized light. The first oxidation potential on absorbed monolayers was found by cyclic voltammetry to be resolved into two peaks indicative of two electrochemically distinct subpopulations of molecules, atributed to aggregates and monomerics forms of PA functionalized ZnPcs. Potential modulated ATR (PM-ATR) spectroelechtrochemistry was employed to measure the charge transfer rates constants (k(s,app)) at ITO modified surfaces using TE and TM polarized light. Faster charge transfer rate constants were found for molecules with a smaller tunneling distance. A k(s,app) of 3.9 x 10⁴ s⁻¹ represents the fastest rate measured for PA functionalized ZnPc chromophore tethered to an ITO waveguide electrode by PM-ATR. We synthesized and characterized the first examples of PA functionalized RuPcs to investigate the effect of molecular orientation on charge transfer properties at an ITO/organic interface. PA functionalized RuPcs have the ability to coordinate axial ligand to suppress aggregation, providing the flexibility of connecting the anchoring group through the axial position of the metal and allowing chemisorption of the molecule in plane with ITO. Cyclic voltammetry and ATR UV/vis spectroscopy on the modified ITO surface demonstrated a surface composition of a closed-packed monolayer of monomeric species. Measurement of the charge transfer rates constants demonstrated that RuPc anchored to ITO exhibited slow rates compared to corresponding surface bound ZnPcs. Finally, we describe the synthesis and characterization of a new PA functionalized N-pyridinyl perylenediimide (PDI)-RuPc donor-acceptor dyad capable of chemisorption to ITO surfaces as a molecular-level heterojunction system to study photo induced charge separated states. The developed ensemble was proven to be stable on ITO for further study of charge injection events from the dyad to the oxide surface.
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19

Bremer, Matthias [Verfasser]. "Functionalized photochromic surfaces switched by organic light-emitting diodes / Matthias Bremer." Kiel : Universitätsbibliothek Kiel, 2018. http://d-nb.info/1154434001/34.

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20

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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21

Xia, Chao. "Characterizations of as grown and functionalized epitaxial grapheneg rown on SiC surfaces." Doctoral thesis, Linköpings universitet, Halvledarmaterial, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-120893.

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The superior electronic and mechanical properties of Graphene have promoted graphene to become one of the most promising candidates for next generation of electronic devices. Epitaxial growth of graphene by sublimation of Si from Silicon Carbide (SiC) substrates avoids the hazardous transfer process for large scale fabrication of graphene based electronic devices. Moreover, the operation conditions can potentially be extended to high temperatures, voltages and frequencies. This thesis is focused on characterizations of as grown and functionalized epitaxial graphene grown on both Si-face and C-face SiC. Synchrotron radiation-based techniques are employed for detailed investigations of the electronic properties and surface morphology of as grown and functionalized graphene. Large area and homogeneous monolayer (ML) graphene has been possible to grow on SiC(0001) substrates by sublimation, but efforts to obtain multilayer graphene of similar quality have been in vain. A study of the transport behavior of silicon atoms through carbon layers was therefore performed for the purpose to gain a better understanding of the growth mechanism of graphene on Si-face SiC. It showed that a temperature of about 800°C is required for Si intercalation into the interface to take place. Intercalation of Si was found to occur only via defects and domain boundaries which probably is the reason to the limited growth of multilayer graphene. Annealing at 1000-1100°C induced formation of SiC on the surface and after annealing above 1200°C Si started to de-intercalate and desorb/sublimate. Different alkali metals were found to affect graphene grown in SiC quite differently. Li started to intercalate already at room temperature by creating cracks and defects, while K, Rb and Cs were found unable to intercalate into the graphene/SiC interface. Effects induced by the alkali metal Na on graphene grown on both Si-face and C-face SiC were therefore studies. For the Si-face, partial intercalation of Na through graphene was observed on both 1 ML and 2 ML areas directly after Na deposition. Annealing at a temperature of about 75°C strongly promoted Na intercalation at the interface. The intercalation was confirmed to start at domain boundaries between 1 ML and 2 ML areas and at stripes/streaks on the 1 ML areas. Higher annealing temperature resulted in desorption of Na from the sample surface. Also for C-face graphene, a strong n-type doping was observed directly after Na deposition. Annealing at temperatures from around 120 to 300 °C was here found to result in a considerable π-band broadening, interpreted to indicate penetration of Na in between the graphene layers and at the graphene SiC interface. The thermal stability of graphene based electronic devices can depend on the choice of contact material. Studies of the stability and effects induced by two commonly used metals (Pt and Al) on Si-face graphene were carried out after deposition and after subsequent annealing at different temperatures. Both Al and Pt were found to be good contact materials at room temperature. Annealing at respectively ~400 ºC and ~ 800 ºC was found to trigger intercalation of Al and Pt into the graphene/SiC interface, and induce quasi-free-standing bilayer electronic properties. Contacts of Pt can thus withstand higher temperatures than Al contacts. For Al inhomogeneous islands of different ordered phases were observed to form on the surface during annealing, while this was not the case for Pt. The initial single π-band structure was in the Al case restored after annealing at ~1200 ºC although some Al remained detectable from the sample. For Pt, the bilayer graphene electronic properties induced by intercalation were thermally stable up to 1200ºC. In the case of Al the stability and effects induced on C-face graphene were also investigated for comparison, and significant differences were revealed. An ordered Al-Si-C compound was found to form after annealing at temperatures between ca. 500ºC and 700ºC. Formation of this compound was accompanied with a large reduction of graphene in the surface region. Annealing at temperatures above 800°C resulted in a gradual decomposition of this compound and regrowth of graphene. No Al signal could be detected after annealing C-face graphene at 1000°C. Graphene grown on C-face SiC has attracted high interest since its mobility has been reported to be one order of magnitude higher compared to Si-face graphene. C-face graphene has moreover been claimed to be fundamentally different compared to Si-face graphene. A rotational disorder between adjacent graphene layers has been suggested that effectively decouples the graphene layers and result in monolayer electronic properties of multilayer C-face graphene. The domain/grain size is typically much smaller for C-face graphene and the number of graphene layers less uniform than on Si-face graphene. Using LEEM and micro-LEED we showed that there is no rotational disorder between adjacent layers within the domains/grains but that they had different azimuthal orientations. Using nano-APRES, we recently also revealed that multilayer Cface graphene show multiple π-bands and Bernal stacking, similar to multilayer Si-face graphene.
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22

Almuramady, Nabeel. "Dry friction between rough surfaces of silicon and functionalized gear microelectromechanical systems." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/103001/.

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Microelectromechanical systems (MEMS or micro-electro-mechanical systems) is a branch of nanotechnology studying microscopic devices, especially those with moving parts. Microgear MEMS is probably the most common type of MEMS that involves transmission of rotational motion between a gear pair. Understanding of physical and chemical mechanisms related to friction between components of microgear MEMS is important for their design and accurate prediction of their tribological properties. In this thesis, various problems related to modelling of tribological performance of silicon microgear MEMS are under investigation. The microgear MEMS teeth have been simulated in the vacuum environment and, therefore, the energy dissipation mechanisms may be reduced the dissociation of chemical and van der Waals interactions as well as the elastic interlocking between counterparts subscale asperities. The models developed have been used to simulate various tribological phenomena, including adhesion, friction, wear and the elastic interlocking of the tooth surfaces. The MEMS tooth roughness is described using statistical approach in accordance with the experimental data obtained by AFM (Atomic Force Microscopy). It has been shown that the microgear MEMS tooth surface roughness does not have any microscale roughness and hence, there is no plastic deformation of the atomic and adhesive subscale asperity due to the Polonsky-Keer effect. The tooth asperity of microgear MEMS is modelled as a nanoblock obtained by superposition of two hierarchical subscales that are specified by the character of interactions at the subscale: an atomic subscale, where chemical interactions are likely to occur, adhesive subscale, where molecular adhesion (van der Waals interaction) is significant and bulk elastic material. The tooth surface is covered by the nanoasperity blocks. According to the roughness studies, a real silicon rough surface has been described at different scales: nanoscale that include atomic subscale of active chemical interactions and molecular subscale of active van der Waals interactions, and bulk elastic scale. The Borodich-Savencu (B-S) one level model that have been developed before for tribology of nominally flat surfaces has been developed. In order to mirror the specific features of interactions between MEMS teeth, the B-S model assumed the gap between the surfaces is constant, while the gap in a gear MEMS pair is changing during the mesh cycle. This was taken into account by the iterative solutions of two-dimensional frictional Hertz-type problems using the Cardiff numerical solver. The new model allows us to model tribology of curved teeth using nanoblocks consisting of atomic and molecular subscales located at varying levels. The apparent friction force and coefficient of friction μ have been calculated by estimations of the total energy per unit length dissipated through the above-mentioned physical and chemical mechanisms. It has been shown that there is a high possibility of stiction (cohesion or the so-called cold welding) between pure silicon MEMS teeth. To improve the system performance and to find ways for controlling III friction effects and reducing stiction possibility, it is suggested to functionalise the MEMS microgear tooth surfaces by self-assembled monomolecular (SAM) layers. A damage model has been developed to study the damage accumulation and wear of these carbon-based functionalised monomolecular layers. The model is based on the Goryacheva-Torskaya model for damage accumulation in fatigue elements. The maximum damage occurs under action of the maximum load, hence the dry friction contact of a single tooth contact is considered. To use the damage model, the surface stresses are calculated. Numerical simulations for silicon-based MEMS micro-tooth surfaces functionalised by monomolecular layer carbon-based coatings show that initially the surfaces do not stick to each other. However, the stiction occur after some number of cycles because the functionalised monomolecular is gradually worn away due to damage accumulation in the layer.
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23

Wang, Jianli. "Design and Characterization of Central Functionalized Asymmetric tri-Block Copolymer Modified Surfaces." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/29574.

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Well-defined central functionalized asymmetric tri-block copolymers (CFABC) were designed as a new type of polymer brush surface modifier, with a short central functionalized block that can form chemical bonds with a suitable substrate surface. A combination of sequential living anionic polymerization and polymer modification reactions were used for the synthesis of two CFABCs: PS-b-poly(4-hydroxystyrene)-b-PMMA and PS-b-poly(4-urethanopropyl triethoxysilylstyrene)-b-PMMA. GPC and NMR characterization indicated that the block copolymers possessed controlled molecular weights and narrow molecular weight distributions. CFABC polymer brushes were successfully prepared by chemically grafting PS-b-poly(4-urethanopropyl triethoxysilylstyrene)-b-PMMA onto silicon wafer surfaces. AFM, XPS and ellipsometry were used to confirm the CFABC polymer brush structures and thickness. The surface properties of CFABC polymer brush modified silicon wafer substrates subjected to different environmental parameters were studied. Reversibly switchable surface energies were observed when the polymer brush modified surfaces were exposed to solvents with different polarities. The phenomenon was attributed to the chain configuration auto-adjustment in the polymer brush systems. The same mechanism was also used to explain the enhanced adhesion capability between the modified surfaces and different polymer materials (PS and PMMA). Phase behaviors of polymer thin films on unmodified and CFABC polymer brush modified silicon wafer surfaces were also studied. For thin films of polymer blends, PS blend PS-co-PMMA, the effects of film thickness, chemical composition and temperature on the phase separation mechanism were investigated. The phase behavior in thin films of triblock copolymers with or without central functionalities were compared to reveal the role of the central functionalized groups in controlling film structures. Finally, the presence of CFABC polymer brush at the interface between PS-b-PMMA diblock copolymer thin film and silicon wafer substrate was found to decrease the characteristic lamellar thickness in the thin film. A mechanism of tilted chain configurations in the thin film due to the interactions with the CFABC polymer brushes was proposed.<br>Ph. D.
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24

Schieber, Romain Verfasser], and Frank [Akademischer Betreuer] [Mücklich. "Novel functionalized and patterned surfaces for cardiovascular applications / Romain Schieber ; Betreuer: Frank Mücklich." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2018. http://d-nb.info/1171212968/34.

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25

Uzarski, Joshua Robert. "Investigations of Bacteria Viability on Surfaces Using ω-functionalized Alkanethiol Self-Assembled Monolayers." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/33685.

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The structure/function relationship between bacteria and biocidal molecules in the vapor or solution phase is well-understood. However, the fundamental structure/function relationship between covalently-bound biocidal surface molecules and bacteria is not. While a number of antibacterial surfaces have been reported, detailed analysis of the molecular scale surface structure has not been performed. The lack of structural knowledge makes it difficult to determine how alterations to the surface affect the viability of the bacteria. Most of the antibacterial surfaces reported to date are composed of polymer systems. Controlling the properties of large surface-bound molecules like polymers is difficult. Self-assembled monolayers, or SAMs, of alkanethiols on gold have been used extensively in the past 20 years as model surfaces for investigation of a large breadth of surface phenomena. SAMs allow for control of the molecular scale surface structure and are amenable to a great number of characterization techniques. The primary objective of the work in this study is to establish the use of SAMs as a tool to investigate the fundamental relationship between surface structure and bacteria viability. The surfaces were characterized before interaction with bacteria by reflection-absorption infrared spectroscopy (RAIRS) and X-ray photoelectron spectroscopy (XPS). Determination of the viability of Escherichia coli on the surfaces was performed via the antibacterial assay. In the assay, a culture of E. coli was sprayed onto the surfaces using a chromatography sprayer. After addition of growth agar and overnight incubation, the number of colony forming units on the surface were counted. Statistical analyses were performed to compare the number of colony forming units on different surfaces. Surfaces were characterized after the assay by RAIRS. The RAIR spectra indicated that no significant change to the well-ordered alkane chain configuration was evident. The structural stability shown by the SAMs will allow for their use in future studies to determine fundamental relationship between surface structure and bacteria viability.<br>Master of Science
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26

Pham, Van Dong. "STM characterization of functionalized carbon nanotubes and graphene." Sorbonne Paris Cité, 2015. http://www.theses.fr/2015USPCC245.

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Dans cette thèse, nous avons étudié l'interaction entre des molécules organiques et des nanomatériaux de carbone. En utilisant un microscope à effet tunnel (STM) à basse température et sous ultra-vide, nous avons mesuré les propriétés de molécules de porphyrine physisorbées sur du graphène ou des nanotubes de carbone. Nous avons d'abord étudié l'injection d'électrons dans le graphène sur des défauts (joints de grains et atomes d'azote insérés). Une étude d'états image résonants nous a également permis de mettre en évidence une variation locale du travail de sorite dans le graphène dopé. Nous avons ensuite étudié les propriétés de molécules de porphyrine (H2TPP) adsorbées sur une surface Au(111). En utilisant la pointe du microscope nous avons induit des réactions de tautomérisation et de déshydrogénation et montré comment cela modifie les états moléculaires et l'interaction molécule-surface. Nous avons ensuite étudié l'interaction du graphène avec des molécules de porphyrine. Nous avons montré que le couplage électronique est faible entre les molécules et le graphène. Nous avons ensuite montré comment un atome d'azote inséré dans le réseau de carbone du graphène modifie l'interaction molécule-surface. Une diminution de l'énergie des états moléculaires au niveau des sites dopants révèle un transfert de charge partiel entre les sites d'azote et les molécules. Dans la dernière partie, nous avons étudié les propriétés de nanotubes de carbone monoparois fonctionnalisés par un polymère de porphyrine. Les mesures ont révélé que le polymère couvre partiellement les nanotubes. La spectroscopie locale a indiqué que la densité d'états locale est modifiée au niveau du polymère<br>In this thesis we studied the interaction between organic molecules and carbon nanomaterials. Using scanning tunneling microscopy (STM) at low temperature and in ultra-high vacuum, we measured the properties of porphyrin molecules at the surface of graphene and single-walled carbon nanotubes. We first studied electron injection in graphene at defect sites (grain boundaries and nitrogen doping atoms). Using image-potential states, we evidenced the variation of local work function in doped graphene. Secondly, we investigated the properties of free-base porphyrin (H2TPP) molecules adsorbed on a Au(111) surface. We performed tip-induced tautomerization and dehydrogenation of the molecules, and revealed how these operations modify the molecular states and molecule-substrate interaction. Following these two preliminary studies, we studied the interaction of graphene with porphyrin molecules. We evidenced a weak electronic coupling between the molecules and graphene. We then showed how a nitrogen dopant on doped graphene can tune the molecule-surface interaction. The comparison between molecules adsorbed on nitrogen doping sites with those adsorbed on carbon sites clearly reveals a downshift of the energy of the molecular states at the doping sites. This downshift reveals a partial electron transfer from the nitrogen sites of graphene to the adsorbed molecules. In the last part of this thesis, we studied the properties of single-walled carbon nanotubes functionalized with a porphyrin polymer. The STM measurements revealed that the polymer is partially covering the nanotubes. Local spectroscopy indicated that the local density of states are modified at the polymer location
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27

Solares, Rivera Santiago de Jesus Goddard William A. "Multi-scale simulations of single-walled carbon nanotube atomic force microscopy and density functional theory characterization of functionalized and non-functionalized silicon surfaces /." Diss., Pasadena, Calif. : Caltech, 2006. http://resolver.caltech.edu/CaltechETD:etd-05122006-102528.

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28

Stahl, Sarah M. "An Investigation of Electrostatic Interactions Between Organically Functionalized Silica Particles, Surfaces, and Metal Ions." OpenSIUC, 2012. https://opensiuc.lib.siu.edu/dissertations/529.

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This research focuses on the electrostatic interactions between silica particles and either coated surfaces or metal ions. This work has two objectives: to begin a preliminary investigation into particle-surface systems that may be ideal for further investigation as a sensor and to investigate metal-ligand interactions for the potential use of metal ions to aid in the self assembly of silica particles. Silica particles with various organic functionalizations were synthesized from trialkoxysilane precursors using variations of the Stöber synthesis method, a well-known colloidal suspensions technique. The functional groups that were used in this work include mercaptopropyl (MPTMS), ethylenediamine (enTMOS), and aminopropyl groups (APTES). The aminopropyl functionalized particles were synthesized by varying the mol% of APTES in a tetraethoxyorthosilicate (TEOS) particle formulation. Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) were used to analyze the particles for size, shape, and composition. Silica particles with all three functionalizations were used for the particle-surface study, whereas only MPTMS particles were used in the metal-ligand study. The coatings used for the particle-surface study were synthesized using standard sol gel chemistry with trialkoxysilane precursors as well. The functional groups used in this study include methyl (MTMOS) and aminopropyl groups (TEOS/APTES). Sol gel coatings incorporating carboxy and ammonium groups were also investigated but were not suitable for further study. FTIR was used to analyze the MTMOS and TEOS/APTES coatings. The adsorption of the MPTMS particles onto TEOS/APTES coatings and enTMOS or TEOS/APTES particles onto MTMOS coatings over time was monitored using fluorescence spectroscopy. Since silica particles are not fluorescent in the visible light range, a fluorescent dye was incorporated into the particles, either rhodamine (MPTMS particles) or pyranine dye (enTMOS, TEOS/APTES particles). The enTMOS and TEOS/APTES particles were protonated to increase the charge of the particles; the increased charge was verified with titration curves of the particles before and after protonation. Two types of MPTMS particles were used for the metal-ligand investigation. The first was the same MPTMS particles (without fluorescent dye) used in the first study. The second was 10 mol% MPTMS concentration in a TEOS particle formulation, similar to the APTES functionalized particles used in the first study. Lead(II) and zinc(II) solutions of varying concentrations was added to the particles, and the self assembly of the particles with no metal ions along with the various concentrations was analyzed using SEM. The nature of the metal-ligand binding was investigated using both mercaptopropyl functionalized particles by adding zinc(II), copper(II), silver(I), and lead(II) solutions to the particles in varying concentrations and analyzing the metal ion binding location using FTIR analyses.
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29

Huang, Yi-Shiang. "Intraocular lenses with surfaces functionalized by biomolecules in relation with lens epithelial cell adhesion." Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0464/document.

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L’Opacification Capsulaire Postérieure (OCP) est la fibrose de la capsule développée sur la lentille intraoculaire implantée (LIO) suite à la dé-différenciation de cellules épithéliales cristalliniennes (LECs) subissant une transition épithélio-mésenchymateuse (EMT). La littérature a montré que l'incidence de l’OCP est multifactorielle, dont l'âge ou la maladie du patient, la technique de chirurgie, le design et le matériau de la LIO. La comparaison des LIOs en acryliques hydrophiles et hydrophobes montre que les premières ont une OCP plus sévère, médiée par la transition EMT. En outre, il est également démontré que l'adhérence des LECs est favorisée sur des matériaux hydrophobes par rapport à ceux hydrophiles. Une stratégie biomimétique destinée à promouvoir l’adhérence des LECs sans dé-différenciation en vue de réduire le risque de développement de l’OCP est proposée. Dans cette étude, les peptides RGD, ainsi que les méthodes de greffage et de quantification sur un polymère acrylique hydrophile ont été étudiés. La surface fonctionnalisée des LIOs favorisant l'adhérence des LECs via les récepteurs de type intégrine peut être utilisée pour reconstituer la structure capsule-LEC-LIO en sandwich, ce qui est considéré dans la littérature comme un moyen de limiter la formation de l‘OCP. Les résultats montrent que le biomatériau innovant améliore l'adhérence des LEC, et présente également les propriétés optiques (transmission de la lumière , banc optique) similaires et mécaniques (force haptique de compression, force d'injection de la LIO) comparables à la matière de départ. En outre, par rapport au matériau hydrophobe IOL, ce biomatériau bioactif présente des capacités similaires vis à vis de l’adhérence des LECs, le maintien de la morphologie, et l'expression de biomarqueurs de l’EMT. Les essais in vitro suggèrent que ce biomatériau a le potentiel de réduire certains facteurs de risque de développement de l’OCP<br>Posterior Capsular Opacification (PCO) is the capsule fibrosis developed onto the implanted IntraOcular Lens (IOL) by the de-differentiation of Lens Epithelial Cells (LEC) undergoing Epithelial-Mesenchymal Transition (EMT). Literature has shown that the incidence of PCO is multifactorial including patient’s age or disease, surgical technique, and IOL design and material. Reports comparing hydrophilic and hydrophobic acrylic IOLs show the former has more severe PCO after EMT transition. Additionally, the LEC adhesion is favored onto the hydrophobic materials compared to the hydrophilic ones. A biomimetic strategy to promote LEC adhesion without de-differentiation to reduce PCO development risk is proposed. RGD peptides, as well as their grafting and quantification methods on a hydrophilic acrylic polymer were investigated. The surface functionalized IOL promoting LEC adhesion via integrin receptors can be used to reconstitute the capsule-LEC-IOL sandwich structure, which is considered to prevent PCO formation in literature. The results show the innovative biomaterial improves LEC adhesion, and also exhibits similar optical (light transmittance, optical bench) and mechanical (haptic compression force, IOL injection force) properties comparing to the starting material. In addition, comparing to the hydrophobic IOL material, this bioactive biomaterial exhibits similar abilities in LEC adhesion, morphology maintenance, and EMT biomarker expression. The in vitro assays suggest this biomaterial has the potential to reduce some risk factors of PCO development
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30

Han, Yinhua. "Label-free detection of biomolecules by a field effect transistor microarray biosensor with bio-functionalized gate surfaces." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=982123027.

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31

Prünte, Stephan [Verfasser], Jochen M. [Akademischer Betreuer] Schneider, and Ulf [Akademischer Betreuer] Jansson. "$n$-Octadecylphosphonic acid functionalized tool surfaces for metal-forming applications / Stephan Prünte ; Jochen M. Schneider, Ulf Jansson." Aachen : Universitätsbibliothek der RWTH Aachen, 2020. http://d-nb.info/1231317353/34.

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32

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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33

Lima, Francisco Nogueira. "Interfaces híbridas de estireno sobre silício." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-06102014-115406/.

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Este trabalho trata do estudo teórico atomístico das conformações da molécula de estireno sobre a superfície de Si(100)(2xl):H. Estudamos a molécula fisissorvida e quimissorvida sobre esta superfície. Os cálculos foram realizados através de Dinâmica Molecular Clássica. Nós reparametrizamos o Universal Force Field (UFF) com base em cálculos ab initio para sistemas modelo, e comparação a dados experimentais. Nossos resultados indicam que no processo de fississorção a região de vale da superfície é preferencial, e ocorre formação de agregados de moléculas antes do contato com a superfície. Quando passamos à análise da quimissorção de uma molécula, a região de vale permanece sendo o sítio preferencial para a posição do grupo vinil. Para as conformações de linhas de estireno, a estrutura mais estável tem todas as moléculas dispostas sobre a região de vale (ordenamento tipo \"pilha-1r\"); identificamos também outra estrutura, quase degenerada em energia, na qual o grupo vinileno se dispõe em conformação tipo \"espinha de peixe\", alternando entre a região de vale e sobre o dímero.<br>In this work we present a theoretical study of ,the conformation of styrene molecules on the Si(100)(2xl):H surface. We studied the conformations for styrene molecules physisorbed and chemisorbed on this surface. The study was conducted by Classical Molecular Dynamics. We performed a re-parametrization of the Universal Force Field (UFF), based on ab initio calculations for model structures, and comparison to experimental data. Our results show that for the physisorbed situations, the styrene molecules preferentially interact with the surface valley. We also identified that the molecules aggregate in clusters before reaching the surface. The valley is again the region of lowest energy for the vinylene position, for chemisorption of a single styrene molecule on the monohydride surface. For systems where we have a styrene layer chemisorbed on the dimer row, the most stable structure has ali the molecules arranged on the valley region o f the surface ( 1r -stack); we find another structure, almost degenerate in energy, in which molecules arrange in a herringbone- like configuration, with the vinylene group alternating between the valley and dimer regions.
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34

Kullmann, Simon Michael [Verfasser], and Martin [Akademischer Betreuer] Hartmann. "Polymer-Enzyme Thin Films : Assembly, Characterization and Stability of Bio-functionalized Surfaces / Simon Michael Kullmann. Betreuer: Martin Hartmann." Erlangen : Universitätsbibliothek der Universität Erlangen-Nürnberg, 2012. http://d-nb.info/102811219X/34.

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35

Wang, Lian. "Synthesis and Characterization of Functionalized Bio-Molecular Surfaces with Self-Assembled Monolayers and Bioreactive Ligands for Nano/Biotechnological Applications." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195096.

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In this work, the synthesis and characterization of functionalized biosurfaces that can be used for bioseparations and bio-nanotechnology are reported. A novel protein purification technique that incorporates chelating ligands and polymers onto the same chromatographic matrix is explored. A polysaccharide based gel, agarose, was modified systematically with hybrid ligands of the chelator iminodiacetic acid (IDA) and the polymer polyethylene glycol (PEG). The PEG molecule acts as a blocking polymer that can allow only small proteins to permeate onto the matrix surfaces and form conventional immobilized metal ion affinity chromatographic (IMAC) interactions with the chelators. Kinetic studies of chelator and polymer attachment were performed in order to effectively control the chelator and polymer densities on the matrix. Studies with different PEG surface densities and their effects on the adsorption of several proteins (e.g. myoglobin, lysozyme and bovine serum albumin (BSA)) were evaluated to characterize these new hybrid size exclusion IMAC (SEIMAC) matrices. An exclusion effect was observed while adsorption as observed in IMAC systems took place.Functionalization schemes and procedures were extended in the activation and incorporation of affinity ligands on inorganic surfaces such as gold surfaces. Functional gold platforms were explored for development of nano-interconnects via functionalized self assembled monolayers (FSAMs) on gold to attach specific affinity ligands as linkers to immobilize biomolecules, such as microtubules (MTs). MTs eventually could be utilized as self assembling structures and templates for fabrication of nano-scale bio-interconnect arrays and networks. In this work, different organothiols were used to form FSAMs and anti-glutathione S-transferase was attached as a linker to utilize the attachment of MT cap proteins, gamma-tubulin. The gamma-tubulin could recognize specifically a heterodimer of the MTs and can provide a nucleation center for MT growth. Several methodologies were employed including photolithographic methods and the use of photoreactive compounds for proper micro/nano scale dual protein functionalization of surfaces with homogeneous affinity ligands and with heterogeneous ligands as well.
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36

Hill, Jacob A. Hill. "SURFACE LAYER MATRIX-ASSISTED LASER DESORPTION IONIZATION TIME OF FLIGHT MASS SPECTROMETRY (SL-MALDI-TOF MS) ANALYSIS OF POLYMER BLEND SURFACE COMPOSITION." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1514479406062149.

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37

Faber, Erik Jouwert. "Towards the hybrid organic semiconductor fet (hosfet) electrical and electrochemical characterization of functionalized and unfunctionalized, covalently bound organic monolayers on silicon surfaces /." Enschede : University of Twente [Host], 2006. http://doc.utwente.nl/55446.

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38

Martin, Volker [Verfasser], and Joachim P. [Akademischer Betreuer] Spatz. "Preparation of Dual Functionalized Surfaces for Covalent Immobilization of BMP-6 and Adhesive Ligands for Biological Applications / Volker Martin ; Betreuer: Joachim P. Spatz." Heidelberg : Universitätsbibliothek Heidelberg, 2017. http://d-nb.info/1178010058/34.

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39

Tunc, Deniz. "Synthesis of functionalized polyamide 6 by anionic ring-opening polymerization." Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0178/document.

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Les études présentées dans le cadre de cette thèse visent à copolymériser l'ԑ-caprolactame (CL) avec différents dérivés de l'α-amino-ԑ-caprolactame (qui possèdent une amine primaire fonctionnalisable) par polymérisation anionique par ouverture de cycle. En utilisant cette stratégie, nous décrivons; (i) la préparation de polyamides 6 fluorés thermiquement plus stables, et ayant une surface hydrophobe; (ii) la synthèse de polyamides 6 portant des groupes pendants cinnamoyl thermo et photosensibles. Une réticulation réversible est observée ainsi que l'amélioration des propriétés thermo-mécaniques; (iii) la copolymérisation anionique par ouverture de cycle de CL avec un bis-monomère issu de l'α-amino-ԑ-caprolactame comme contrôle de la réticulation du polyamide 6. Enfin, dans le cadre de notre intérêt continu pour la chimie du polyamide 6, nous avons mis en évidence la possible combinaison de la polymérisation anionique par ouverture de cycle de CL avec la polycondensation en chaîne de l'éthyl-4-butylaminobenzoate pour obtenir en une étape un polyamide aliphatique/aromatique<br>The studies presented in this thesis aim to copolymerize ԑ-caprolactam (CL) with different derivatives of α-amino-ԑ-caprolactam (which has a functionalizable primary amine) via anionic ring-opening polymerization. By using this strategy, we describe: (i) the synthesis of thermally more stable fluorinated polyamide 6 having a hydrophobic surface; (ii) the synthesis of polyamides 6 bearing pendant cinnamoyl groups, which are thermo-and photoresponsivechromophore groups, and demonstrating their reversible crosslinking as well as improved thermo-mechanical properties; (iii) the copolymerization ofCL with a crosslinker (N-functionalized α-amino-ԑ-caprolactambis-monomers) into crosslinked polyamides 6.As part of our continuing interest in polyamide 6 chemistry, we developed the combination of anionic ring-opening polymerization of CL and chain-growth condensation polymerization of ethyl 4-butylaminobenzoate in order to obtain aliphatic/aromatic polyamides in one-step
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40

Pielak, Kornelia. "Commutation des réponses optiques non linéaires du second ordre des indolino-oxazolidines : des molécules en solution aux surfaces fonctionnalisées." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0096.

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Cette thèse étudie les réponses de génération de second harmonique (GSH) de dérivés d’indolino-oxazolidines dans différents environnements. Ces molécules sont des interrupteurs moléculaires : sous l’action de stimuli externes, elles peuvent commuter entre une forme fermée incolore et une forme ouverte colorée. Les deux formes se distinguent par leurs réponses optiques non linéaires (ONL) du deuxième ordre, associées à un grand contraste de première hyperpolarisabilité . La combinaison de ces propriétés fait de ces molécules des candidats pour la réalisation de mémoires à l’échelle moléculaire, alliant stockage multiple et lecture non destructive. En particulier, cette thèse démontre que les performances de commutation ONL sont préservées en passant des molécules en solution aux monocouches auto-assemblées (MAAs). Les études adoptent une approche multidisciplinaire combinant des mesures des réponses optiques linéaires et non linéaires des interrupteurs moléculaires en solution avec des simulations numériques des molécules en solution et sous la forme de MAAs. Les principaux résultats sont 1°) l’étude comparative des réponses de diffusion hyper-Rayleigh et de génération de second harmonique induite par un champ électrique (GSHIE) de ces molécules en solution, laquelle a mis en évidence que ces réponses peuvent être très différentes à cause de l’amplitude et de l’orientation du moment dipolaire mais aussi à cause de valeurs non négligeables de la contribution ONL du troisième ordre à la GSHIE, 2°) l’étude des effets de substitution – du groupement méthyle de l’oxazolidine par un groupement nitro accepteur ou de l’unité bithiophène par un groupement ferrocène – sur les réponses ONL et l’interprétation de la diminution du contraste des premières hyperpolarisabilités entre les formes ouverte et fermée, et 3°) l’implémentation et l’optimisation d’une méthode numérique multi-échelle (DM-puis-MQ) pour prédire les réponses ONL de systèmes dynamiques. Dans cette méthode la première étape consiste à générer des structures molécules en utilisant la dynamique moléculaire (DM), ensuite, pour une sélection de ces structures, les propriétés moléculaires sont évaluées avec différentes méthodes de mécanique quantique (MQ). Les résultats obtenus et la mise au point de cette méthode ouvrent la voie à l’étude des systèmes ONL dynamiques et à l’optimisation de leurs réponses de GSH<br>This thesis reports on a detailed characterization of the second harmonic generation (SHG) responses of indolino-oxazolidine derivatives in different environments. These molecular switches are particularly interesting because they can commute between a colorless closed form and a colored open form when triggered by various external stimuli. The two forms display different second-order nonlinear optical (NLO) responses and a huge contrast of the associated value, making these systems interesting for applications in molecular-scale memory devices with multiple storage and nondestructive read-out capacity. In particular, this thesis demonstrates that the performance of the NLO switches remains when forming self-assembled monolayers (SAMs). This investigation is carried out by using a multi-disciplinary approach that combines measurements of the linear and nonlinear optical responses of the switches in solution with theoretical chemistry calculations performed for molecules in solutions as well as in SAMs. The main results include 1 ) a comparative analysis of the hyper-Rayleigh scattering (HRS) and electric-field induced SHG (EFISHG) responses of the molecules in solution, demonstrating they could be much different owing to the amplitude and orientation of the dipole moment as well as to the non-negligible third-order NLO contribution to EFISHG, 2 ) the investigation of the effects of adding an acceptor nitro group on the oxazolidine of substituting the bithiophene donor group by an alternative ferrocene unit, which both reduce the contrast, and 3 ) the implementation and optimization of a multi-scale numerical method (MD-then-QM) to predict the NLO responses of dynamical systems, which consists in sampling the system geometries and structures using molecular dynamics (MD) and then in evaluating the NLO responses at ab initio quantum mechanical levels (QM). These results as well as the implemented method open the way to investigate new dynamical systems and to design efficient NLO switches
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41

Yan, Xiang. "Design of biphasic polymeric fiber from melt-spinning charged with nanoparticles : effects of the formulation and the fillers localization, to obtain a functionalized fiber at surface level." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1I084.

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Le but de ce travail est de développer des filaments fonctionnels de polypropylène (PP) poreuses mais aussi des microfibres de PP par filage voie fondu de mélange de polymères immiscibles PP/Poly(vinyl-alcool) (PVA) après extraction sélective de la phase de PVA. Le premier objectif est de déterminer le ratio optimal entre le PP et le PVA afin d’obtenir la filabilité du mélange et de localiser les charges à l’interface du mélange biphasique. Les charges utilisées sont à la fois des nanoparticules de silices modifiées ainsi que des particules Janus à base de kaolinite, favorisant la localisation à l’interface. Les morphologies et les localisations des charges ont été analysées à la fois sur des joncs extrudés ainsi que sur des fibres. Le travail s’est concentré principalement sur des ratios de polymères permettant d’obtenir des fibres de PP poreuses, mais un travail exploratoire a permis de déterminer les conditions d’obtention de microfibres de PP. Le ratio PP/PVA avec 70 % de PP et 30 % de PVA en masse est la formulation idéale pour fabriquer ces fibres poreuses. La localisation des nanocharges de silice dans le mélange biphasique est principalement contrôlée par la thermodynamique du mélange, et en fonction des tensions de surface des nanosilices, la localisation à l’interface a pu être obtenue. De plus, les particules Janus permettent une voie alternative afin d’obtenir une localisation à l’interface, qui apportent un renforcement mécanique de la formulation. La faisabilité de la production de microfibres via l’inversion de phase PVA/PP avec l’ajout de nanocharges a été démontrée<br>The work aims to make the functional porous polypropylene (PP) fibers as well as PP microfibers, by the melt spinning of PP-poly(vinyl alcohol) (PVA) blends followed with the selective phase extraction of PVA. The objective is to first find out the optimal ratio of PP and PVA for fabrication of multifilament yarns by melt spinning, and to localize the filler at the biphasic interface. The fillers include not only the homogenously modified silica nanoparticles, but also the kaolinite Janus particles. The concomitant morphology evolution of the extrudates and fibers were observed. The work mainly discusses about the fabrication of porous fibers, but also makes an exploratory experiment to reverse the ratio to fabricate the microfibers. It was found that the ratio of two polymers as 70 wt.%/30 wt.% is an ideal formula for fabricating the porous fibers. Both of the two fillers are successfully tailored at the biphasic interface. The localization of silica nanoparticles within the biphasic can be fixed by the thermodynamic control, and one of the sorts has been dominantly localized at the biphasic interface. In addition, the Janus particles provide an alternative way to have the interface localization, which even helps the mechanical enhancement. The feasibility of microfiber production with the embedment of the fillers was also demonstrated
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42

Cotton, Christopher Mark. "Characterisation of biologically functionalised surfaces." Thesis, University of Glasgow, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272879.

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43

Downing, Stuart. "Surface-functionalised polymeric nanoparticles." Thesis, University of East Anglia, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.399786.

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44

Rubrice, Kevin. "Matériaux composites commandables pour applications hyperfréquences dans les structures navales." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1S127.

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Les matériaux composites prennent une place de plus en plus importante dans la conception et la fabrication des moyens de transport et notamment dans le domaine naval où ils sont particulièrement privilégiés. En effet, ces matériaux sont utilisés pour leur légèreté, insensibilité à la corrosion et leurs caractéristiques mécaniques. Dans le domaine militaire, où l'optimisation des moyens de communication et de protection électromagnétique est primordiale, le développement de matériaux composites dotés de propriétés de reconfigurabilité sous commande(s) externe(s), présente un atout opérationnel majeur pour les parois structurales exploitant ces matériaux. Afin d'explorer cette voie, DCNS et l'Institut d’Électronique et de Télécommunications de Rennes (IETR, UMR-6164) se sont associés. Les travaux de thèse engagés ont pour objectif d'étudier et de développer des matériaux composites présentant des fonctions de reconfigurabilité applicables aux systèmes navals tels que les radômes, les antennes et exploitables pour répondre aux problématiques de furtivité (SER). Une première étude a permis d'explorer les matériaux à base de carbone, présentant une potentielle agilité de leurs caractéristiques diélectriques sous actuateur électrique. Ces matériaux présentent également un fort pouvoir absorbant électromagnétique, tributaire des propriétés diélectriques, elles-mêmes potentiellement reconfigurables. La seconde étude engagée a étudié l'impact des matériaux ferroélectriques, c'est-à-dire des matériaux reconfigurables sous champ électrique, lorsqu'ils sont intégrés comme charge dans une résine d'imprégnation. Ce nouveau matériau composite présente alors une reconfigurabilité de ses caractéristiques diélectriques, rendant commandable en fréquence sa structure hôte. Une troisième étude, exploitant aussi le matériau ferroélectrique a permis l'obtention d'une reconfigurabilité des caractéristiques de réflectivité de panneaux composites grâce au développement de surfaces sélectives en fréquence reconfigurables. De nouvelles propriétés ont ainsi été mises en évidence en hyperfréquences. Enfin, les matériaux d'âmes et spécifiquement les nids d'abeilles diélectriques ont fait l'étude d'une fonctionnalisation pour des applications DC et hyperfréquences<br>Composite materials are used for their lightness, high resistance to corrosion and high mechanical properties over large application areas, such as naval, ground and aerial. Collaboration between DCNS group and the Institute of Electronics and Telecommunications of Rennes (IETR, UMR-6164) has been initiated to develop smart composite materials with tunable properties at microwaves. Three different routes have been investigated during the thesis work. The first one is based on carbon composite material, its electromagnetic absorbing ability and its potential dielectric tunability. For this, we develop composite materials loaded with various carbon particles (carbon nanotube, graphene, black carbon). Next, to elaborate smart composite materials, a ferroelectric material has been used as filler. The dielectric characteristics of such materials can be tuned under external biasing for example. Thus we develop an active composite material under various external actuators for naval application, and especially for new reconfigurable frequency selective surface (RFSS). Finally dielectric honeycomb materials have been specifically elaborated and studied to develop smart properties for DC and microwave applications. During this work, three different prototypes improving composite materials in naval area have been performed: reconfigurable radome, RCS reduction, and antenna isolation
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45

Mukhopadhyay, Rupa. "Scanning probe microscopy of functionalised metal surfaces." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343521.

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46

Watson, Scott M. D. "Scanning probe lithography of chemically functionalised surfaces." Thesis, Durham University, 2008. http://etheses.dur.ac.uk/2055/.

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A facile route to the production of highly uniform, ultra-thin metal oxide films has-been demonstrated using a combination of self-assembly and Langmuir-Blodgett techniques. Initial modification of a Si/SiO(_2) substrate through self-assembly of an octadecylsiloxane monolayer provides a hydrophobic surface suitable for the "tail down" deposition of a Langmuir-Blodgett monolayer of octadecylphosphonic acid, giving. The resulting –PO(_3)H(_2) functionalised film provides a suitable surface for binding of metal ions (e.g. Zr(^4+), Hf(^4+), Mg(^2+)). The tendency of these metal species to form polymeric structures in aqueous solution allows for the assembly of nanometre thick inorganic metal layers upon the –PO(_3)H(_2) surface. Thermal treatment of the Langmuir-Blodgett films was used to decompose the organic film components, whilst simultaneously calcining the inorganic metal layer, resulting in the formation of highly uniform metal oxide films, typically ca. 1.3 - 1.9 nm thick. Nanoscale patterning of the metal-stabilised Langmuir-Blodgett monolayers has also been demonstrated, by using an AFM probe to apply sufficiently high vertical forces upon the Langmuir-Blodgett surface to selectively displace the monolayer film material within spatially defined surface regions. Pattern resolutions dowm to 30 nm were achieved using this AFM "nanodisplacement" lithographic process. Excellent levels of structural retention of the patterns were also observed upon decomposition of the organic film components to generate the final metal oxide. Similarly, nanodisplacement patterning of metal-stabilised Langmuir-Blodgett monolayers deposited upon amino-flinctionalised substrates has been used for the fabrication of amine patterned surfaces. Selective binding of Au nanoparticles within the amine regions was demonstrated, highlighting the potential of such patterned surfaces as chemical templates for directing the assembly and organisation of other materials
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47

Chen, Peiru. "Surface functionalized TPU for antifouling catheter application." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1525170686769959.

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48

Makarowicz, Anna. "Surface characterisation of functionalised fluoride materials." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491874.

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X-ray Photoelectron Spectroscopy (XPS), X-ray Absorption Fine Structure spectroscopy (XAFS), X-ray Diffraction (XRD) and Pyridine Adsorption Spectroscopy (PAS-S) were used to investigate the solid superacid high surface area AIF3 (HS AIF3). The aim of this work was to establish correlations between Lewis acidity, surface area, geometric and electronic structure of the materials. The aim of this study was to obtain structure/activity relationships for AIF3 materials synthesised by different routes, with a view to future tailoring of the properties of these materials to potential industrial applications.
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49

Bewsher, Alan. "New crosslinking methods for functionalised oligomers." Thesis, Lancaster University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335350.

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50

Kelly, Jonathan M. "Osteoblast response to oxygen functionalised plasma polymer surfaces." Thesis, University of Sheffield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246918.

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