Дисертації з теми "Surface and interfaces"
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Dahal, Arjun. "Surface Science Studies of Graphene Interfaces." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5820.
Повний текст джерелаPurcell, Isabella Pauline. "Specular reflection from interfaces." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386624.
Повний текст джерелаHazell, Gavin D. A. "Surface scattering from soft matter at interfaces." Thesis, University of Bath, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.642031.
Повний текст джерелаWu, Liuming. "Surface complexation at calcium mineral-water interfaces." Doctoral thesis, Luleå, 1994. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-25727.
Повний текст джерелаGodkänd; 1994; 20070429 (ysko)
Maeda, Nobuo, and nobuo@engineering ucsb edu. "Phase Transitions of Long-Chain N-Alkanes at Interfaces." The Australian National University. Research School of Physical Sciences and Engineering, 2001. http://thesis.anu.edu.au./public/adt-ANU20011203.151921.
Повний текст джерелаLi, Zhi Xin. "Neutron reflection from interfaces." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320621.
Повний текст джерелаJohnson, Edward G. "Dynamics of interfaces and detergency." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361250.
Повний текст джерелаBennett, Andrew Michael. "Properties, processes and surface chemistry at diamond interfaces." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434867.
Повний текст джерелаAl-Bermany, Ehssan. "Polymer/graphene oxide nanocomposites : surface adsorption and interfaces." Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/18510/.
Повний текст джерелаIscimen, Mehmet. "Shearing Behavior Of Curved Interfaces." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/7256.
Повний текст джерелаPorter, Stephen Christopher. "Synthesis, surface characterization, and biointeraction studies of low-surface energy side-chain polyetherurethanes /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/9845.
Повний текст джерелаLarsericsdotter, Helén. "Macromolecules at Interfaces." Doctoral thesis, Uppsala University, Centre for Surface Biotechnology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4661.
Повний текст джерелаIn this thesis, the structure and stability of globular proteins adsorbed onto nanometer-sized hydrophilic silica particles were investigated using differential scanning calorimetry (DSC), hydrogen/deuterium exchange (HDX), and mass spectrometry (MS). The adsorption process itself was characterized with fluorescence and absorption spectroscopy and surface plasmon resonance (SPR). The combination of these methods offered a unique insight into adsorption-induced changes within proteins related to their adsorption characteristics. DSC contributed with thermodynamic information on the overall structural stability within the protein population. HDX in combination with MS contributed information on the structure and stability of adsorbed proteins with focus on changes within the secondary structure elements. In order to increase the structural resolution in this part of the investigation, proteolysis was performed prior to the MS analyzing step. Knowledge on the protein adsorption process was utilized in a practical approach called ligand fishing. In this approach, SPR was used to monitor the chip-based affinity purification of a protein with MS used for protein identification.
Adsorption isotherms revealed that electrostatic interactions play an important role in the adsorption of proteins to hydrophilic surfaces. DSC investigation revealed that the thermal stability of proteins reduces with increasing electrostatic attraction between the protein and the surface and that this effect diminishes at higher surface coverage. The mass-increase due to exchange between protein hydrogen atoms and deuterium atoms in solution was investigated as a function of time. This gave insight into adsorption-induced changes in the structural stability of proteins. By combining DSC and HDX-MS, it was possible to differentiate between adsorption-induced changes in the secondary and tertiary structure. Additionally, if limited proteolysis was performed, the investigations gave insight into the orientation and protein segment specific changes in the stability of proteins adsorbed to silica surfaces. The adsorption of proteins to silica particles also provided the basis for a new experimental design that allows handling of minute amounts of proteins in a ligand fishing application, as used in the field of functional proteomics.
Ong, Toon-Hui. "Vibrational spectroscopy of molecules at interfaces." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240827.
Повний текст джерелаSu, Tsueu-Ju. "Neutron and X-ray scattering from interfaces." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319060.
Повний текст джерелаTook, Roger Kenton. "Surface interaction : separating direct manipulation interfaces from their applications." Thesis, University of York, 1990. http://etheses.whiterose.ac.uk/13997/.
Повний текст джерелаThapa, Nabin K. "Characterizing Liquid-Fluid Interfaces Using Surface Light Scattering Spectroscopy." Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent1564059703319064.
Повний текст джерелаNoro, Hisato. "Surface processes at Ag/Fe and Fe/Ag interfaces." Thesis, University of Sussex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239113.
Повний текст джерелаTissot, Héloïse. "Beyond the gap of pressure : XPS studies of interfaces at near ambient pressures." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066615/document.
Повний текст джерелаIn many processes or technological objects, such as coating deposition, advanced material processing for electronics, magnetic or optical devices, electrochemical processes at an electrode, sensors and catalysis, etc. the interface between a surface of a solid and a liquid or a gas phase, plays a prominent role. Analogously, environmental sciences and sciences of the Living integrate into their models chemical reactions taking place at solid/liquid or liquid/gas interfaces.XPS is a powerful technique for interface analysis and has been widely use in the case of solid surface. The main advantage of XPS is its sensitivity to the material surface. Indeed, due to the low electron mean free path of electrons in a solid, only the photoelectrons at the extreme outer surface (1-10 nm) can escape the sample. However, XPS has traditionally been conducted under ultra-high vacuum (UHV) conditions. UHV conditions are utilized for two reasons. First, the analyzers are designed to work under UHV conditions. Second, the electrons must reach the detector and their mean free path is short at high pressures. For example at a pressure of 1 mbar, 100 eV electrons will travel 1 mm while under UHV conditions, the mean free path increases to 105 m. UHV chambers (10-10 mbar) help maximize the mean free path so that a high number of electrons will reach the detector/analyzer and the signal/noise ratio will increase making it possible to analyze the spectrum produced. This constraint makes UHV the standard environment of X-ray Photoelectron Spectroscopy (XPS) experiments.In order to make possible the use of XPS on a larger pressure range, a few groups around the world have designed photoemission equipment that can be operated under ambient pressure (up to 5 mbar). The Berkeley group (M. Salmeron LBNL-Materials Sciences Division, H. Bluhm LBNL-Chemical Sciences Division), who pioneered this field, has two such setups installed at the Advanced Light Source. The Fritz Haber Institute has built a high pressure XPS based on the Berkeley prototype, installed at BESSY synchrotron (Berlin), since 2002. The building of Ambient Pressure XPS (APXPS) analyzers of the Berkeley type, able to be operated at pressures in the range of 1 mbar, about 7 orders of magnitude higher than the pressure limit of conventional UHV equipment is both a technological and conceptual breakthrough. Differential pumping stages allow the sample to remain at environmental pressures, while maximizing the mean free path of emitted electrons, so they can reach the detector. Additionally, voltages are applied to electrostatic lenses in the unit to accelerate and focus the electrons onto the focal plane of the electron energy analyzer. A similar system Near-Ambient Pressure XPS, NAP-XPS), described in details in chapter 1, was delivered in December 2012 and installed at TEMPO beamline in February 2013. The first beamtime occurred in May 2013. During my thesis that started in October 2011 two different projects were developed, both related to interface analysis using the NAP-XPS instrument
Yang, Fuzi. "Optically excited surface polaritons using strongly absorbing media." Thesis, University of Exeter, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279743.
Повний текст джерелаSzabo, Tamas. "Energy transfer at gas-liquid interface towards energetic materials /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4797.
Повний текст джерелаThe entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on February 29, 2008) Vita. Includes bibliographical references.
Arab, Arian. "Probing the Surface- and Interface-Sensitive Momentum-Resolved Electronic Structure of Advanced Quantum Materials and Interfaces." Diss., Temple University Libraries, 2019. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/547230.
Повний текст джерелаPh.D.
In this dissertation, we used a combination of synchrotron-based x-ray spectroscopic techniques such as angle-resolved photoelectron spectroscopy (ARPES), soft x-ray ARPES, hard x-ray photoelectron spectroscopy (HAXPES), and soft x-ray absorption spectroscopy (XAS) to investigate momentum-resolved and angle-integrated electronic structure of advanced three- and two-dimensional materials and interfaces. The results from the experiments were compared to several types of state-of-the-art first-principles theoretical calculations. In the first part of this dissertation we investigated the effects of spin excitons on the surface states of samarium hexaboride (SmB6), which has gained a lot of interest since it was proposed to be a candidate topological Kondo insulator. Here, we utilized high-resolution (overall resolution of approximately 3 meV) angle-resolved and angle-integrated valence-band photoemission measurements at cryogenic temperatures (1.2 K and 20 K) to show evidence for a V-shap
Temple University--Theses
Mao, B. W. "In-situ X-ray diffraction studies of electrochemical interfaces." Thesis, University of Southampton, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378678.
Повний текст джерелаBarraud, Chloé. "Nanorhéologie de fluides complexes aux interfaces." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAY011/document.
Повний текст джерелаLiquids confined present many fascinating behaviors very different from those observed in their volume. Confinement can induce a shift in the balance of phases (eg the liquid-vapor transition, also called capillary condensation), it can change the glass transition temperature of the polymer, or impose order on the molecular arrangement of fluid. The changes in the mechanical properties of liquid interfaces are particularly important in applications. However the level of understanding, the simple case of Newtonian liquids is still controversial, with one hand, numerical simulations show that the viscosity should not be changed for some higher molecular sizes containment, and secondly non-unanimous experiences, sometimes showing qualitative changes in rheological properties under confinement. Recently we have shown that the methods of hydrodynamic impedance sphere-plane geometry is a privileged, non-intrusive method and unambiguous, to discuss the mechanics of nano-liquid interfaces (1,2). As interphase, ie fluid layers whose properties are modified by the proximity of a solid, it is possible to accede their contactless module, so without the disturbance caused by a second surface.S As regards the effect of confinement on the rheology, we have shown that the elastic deformation across the pico meter of confining surfaces, gives a strong modification beyond apparent rheology of the fluid, even in the absence of any intrinsic effect. The thesis aims to implement the hydrodynamic impedance methods to study the rheology of polymer solutions confined. We specifically consider two models of fundamental importance as well as practical systems: brushes grafted polymer whose mechanical properties are an issue in lubrication applications as well as for biological flows and solutions of water-soluble polymers interest in enhanced oil recovery, in order to understand the effects of thinning containment and to distinguish between changes in viscosity and depletion layer induced by the flow. At the instrumental level, one of the challenges of the thesis is to implement the hydrodynamic impedance measurements on two complementary instruments at the level of the probe: the measuring dynamic power (SFA) of Liphy, and AFM interferometric detection developed at the Institut Néel. These different scales of investigation will help to clarify the medium average mechanical properties of liquids confined and their gradients near the wall. A view of work will be to look mechanical and rheological properties of polymer brushes intrinsic determined directly on SFA or AFM with their functional properties: lubricating properties of sliding contacts, or modification of the flow in microchannels. This will continue on the implementation by Lionel Bureau Liphy experimental platform: SFA friction advised biomimetic micro-fluidic systems (walls functionalized polymer brushes). The challenge will be to understand how the mechanical and rheological properties of brushes determine those systems in which they operate
Lenne, Quentin. "Interfaces et nano-objets fonctionnels et biomimétiques pour l'électrocatalyse." Thesis, Rennes 1, 2021. http://www.theses.fr/2021REN1S143.
Повний текст джерелаThe work presented in this manuscript is focused on the surface functionalization of metallic nanoparticles with a covalently-bound monolayers of calix[4]arenes. The catalytic activity of these modified systems was then studied for the activation of small fuel molecules such as oxygen, methanol, and carbon dioxide
Zhang, Xiaochun. "Design and characterization of biomolecule/semiconductor interfaces." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 221 p, 2009. http://proquest.umi.com/pqdweb?did=1833646481&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Повний текст джерелаDedinaite, Andra. "Surface force studies of association phenomena at solid-liquid interfaces." Doctoral thesis, KTH, Chemistry, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-2849.
Повний текст джерелаThe main topics of this thesis, association phenomena inbulk and at solid-liquid interfaces in polar and non-polarmedia, were studied by a range of methods. Direct forcemeasurements employing the interferometric surface forceapparatus (SFA) was the chief technique. In addition, atomicforce microscopy (AFM), X-ray photoelectron spectroscopy (XPS),small angle neutron scattering (SANS), dynamic light scattering(DLS), turbidimetric and electrophoretic mobility measurementswere also applied. These techniques give complementaryinformation, and together they can provide a rather detailedpicture of the fairly complex systems studied.
The first system studied was designed to explore particleinteractions in non-polar media. It consisted of polar or,alternatively, non-polar surfaces immersed in a non-polarmedium, triolein, in some cases containing additives such asphospholipids, polyglycerol polyricinoleate (PGPR), and traceamounts of water. It was investigated how triolein mediates thesurface interactions and how these interactions are affected bythe presence of additives. Triolein adsorbs onto mica surfacesthus producing a barrier against flocculation of the particles.The additives mentioned interact with the surfaces and witheach other, thus altering the surface interactions. Water, forinstance, being strongly polar, preferentially adsorbs ontomica and disturbs the triolein ordering at the mica surfacescausing the barrier against flocculation to vanish. Owing tocapillary condensation of water, a strong adhesion between thesurfaces is instead developed. On the other hand, it could beshown that in the presence of phospholipids, the effect ofwater was opposite: long-range repulsive forces develop due toweakly adsorbed reversed phospholipid aggregates.
The second type of system studied contained cationicpolyelectrolytes and oppositely charged surfactants. Suchsystems occur in numerous technological processes: wastewatertreatment and ore recovery as well as laundry and body care.Polyelectrolytes and surfactants associate in bulk solution,and they also adsorb on surfaces. Thus, the relation betweenthe bulk properties of polyelectrolyte-surfactant mixtures andtheir properties at the solid-liquid interface is of greatscientific and industrial interest. The bulk properties ofpolyelectrolyte-surfactant aggregates were characterised byDLS, SANS, turbidimetry and electrophoretic mobilitymeasurements. It was concluded that to a certain extent theinterfacial properties of polyelectrolyte-surfactant aggregatescan be rationalised by considering their bulk properties.However, it was also shown that the presence of a surfaceaffects the association between polyelectrolytes andsurfactants. The chemical composition of adsorbed aggregates isdifferent from that of aggregates in solution, and, moreover,the structure of surface-bound polyelectrolyte-surfactantaggregates changes slowly with time.
Keywords:Triolein, phosphatidiylethanolamine,phospholipid, lecithin, capillary condensation, polyglycerolpolyricinoleate, aggregation, adsorption, surface forces,structural forces, mica, polar surface, non-polar surface,polyelectrolyte, surfactant, sodium dodecyl sulphate,polyelectrolyte-surfactant association, turbidity,electrophoretic mobility, AFM, SANS, DLS, SFA.
Hahlin, Maria. "Electronic and Molecular Surface Structures of Dye-Sensitized TiO2 Interfaces." Doctoral thesis, Uppsala universitet, Yt- och gränsskiktsvetenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-127166.
Повний текст джерелаBello, D. O. "The lubricant/surface topography interaction at press tool/blank interfaces." Thesis, Brunel University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.481594.
Повний текст джерелаRapisarda, Antonino. "Localized Surface Plasmon Resonance: Nanoscale Sensing for Processes at Interfaces." Doctoral thesis, Università di Catania, 2017. http://hdl.handle.net/10761/4022.
Повний текст джерелаEftekharibafrooei, Ali. "Ultrafast Vibrational Spectroscopy and Dynamics of Water at Interfaces." Diss., Temple University Libraries, 2011. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/107351.
Повний текст джерелаPh.D.
Over the past two decades, vibrational sum-frequency generation (VSFG) has been applied as a versatile technique for probing the structure and dynamics of molecules at surfaces and interfaces. The excellent surface specificity of the SFG allows for probing different kinds of liquid interfaces with no or negligible contribution from adjacent and much deeper bulk phase. VSFG spectroscopy has provided evidence that the structure of the water at interfaces is different from the bulk. With the ultrafast pulses, VSFG can also be used as a probe of ultrafast vibrational dynamics at interfaces. However, apart from a few pioneering studies, the extension of VSFG into time domain has not been explored extensively. Here VSFG is used as a probe of ultrafast vibrational dynamics of water at silica interfaces. Silica is an excellent model system for the solid phase where one can systematically vary the surface charge via bulk pH adjustment. The extension of the surface electric field, the interfacial thickness and surface accumulation of ions at a charged silica surface were studied using IR pump-VSFG probe spectroscopy. A vibrational lifetime (T1) of about 250 fs, similar to bulk H2O, was observed for the O-H stretch of H2O/silica interface when the silica surface is negatively charged. At the neutral surface, where the thickness of interfacial water is smaller than at the charged surface, the vibrational lifetime of O-H stretch becomes more than two times longer (T1~ 600 fs) due to the decreased number of neighboring water molecules, probed by SFG. The fast T1 at negatively charged surface begins to slow down by screening of the penetration of surface electric field via adding salt which suggests the primary reason for similar vibrational dynamics of water at charged interface with bulk water is the penetration of electric field. By decoupling of OH of HDO in D2O, a frequency dependent vibrational lifetime is observed with faster T1 at the red compared to the blue side of the hydrogen bond spectral region. This correlates with the redshift of the SFG spectra with increasing charged surface and is consistent with a theoretical model that relates the vibrational lifetime to the strength of the hydrogen bond network.
Temple University--Theses
Rowe, S. J. "Adsorption studies of simple molecules on metalic, bimetalic and semiconductor interfaces." Thesis, University of Southampton, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383911.
Повний текст джерелаMarana, Naiara Letícia [UNESP]. "Estudo computacional do óxido de zinco puro e dopado com metais de transição: bulk, superfícies, interfaces e nanotubos." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/150977.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A química computacional tem se mostrado uma ferramenta muito útil no meio científico e tem sido cada vez mais utilizada na pesquisa de novos materiais. Dentre os muitos sistemas estudados com o auxílio da química computacional, destaca-se o óxido de zinco (ZnO), muito utilizado em diversos dispositivos eletrônicos tais como, sensores, células solares, diodos de emissão de luz UV e diodos a laser. À temperatura e pressão ambientes, a estrutura cristalina mais estável do ZnO é hexagonal do tipo wurtzita, na qual os átomos de zinco estão coordenados a quatro átomos de oxigênio. Devido a coordenação tetraédrica e falta de centro de simetria dessa estrutura, o ZnO apresenta propriedades piezoelétricas podendo ser aplicado em sensores piezoelétricos, por exemplo. Atualmente, existem muitos trabalhos científicos relacionados com o ZnO, porém o número de trabalhos teóricos em relação aos trabalhos experimentais ainda é pequeno. Neste sentido, este projeto teve como objetivo a análise das propriedades do ZnO em três morfologias diferentes, bulk, superfícies e nanotubos, aplicando as principais técnicas de modelagem computacional aplicada ao estado sólido tais como escolha do funcional de densidade e funções de base, otimização da geometria, dopagem por substituição de átomos, cálculo de constantes elásticas e piezoelétricas, simulação de pressão hidrostática aplicada a célula unitária, secção do bulk para gerar superfícies, substituição de átomos para formar interfaces, nanotubos e adsorção de moléculas nos nanotubos. Os cálculos foram realizados aplicando-se a Teoria do Funcional de Densidade, com o auxilio do programa CRYSTAL14, utilizando o funcional híbrido B3LYP, com o conjunto de funções de base all-electron. A metodologia aplicada conserva a periodicidade dos sistemas cristalinos (1D para nanotubos, 2D para superfícies ou 3D para bulk), em que os blocos de construção são compostos por células unitárias e podem ser replicados pelo operador de simetria. As análises topológicas foram realizadas aplicando-se a Teoria Quântica de átomos em Moléculas de Bader. Após a escolha do nível de teoria, as propriedades estruturais, eletrônicas, vibracionais, topológicas e constantes elásticas e piezoelétricas foram analisadas para o bulk. Partindo da estrutura otimizada, os átomos de zinco foram substituídos por Mn2+ e Al3+, simulando sistemas dopados. Paralelamente, foi realizado o estudo do comportamento das constantes elásticas e piezoelétricas em função da variação de pressão hidrostática, que mostrou a resposta piezoelétrica do ZnO aumenta em função da pressão. Após o estudo do bulk, as superfícies (101 ̅0), (112 ̅0) e (0001) foram analisadas e estudadas através de sua energia superficial, propriedades estruturais, eletrônicas e topológicas. A partir da monocamada da superfície (0001), os nanotubos armchair, zigzag e quiral foram gerados e estudados de acordo com sua obtenção, estabilidade e diferentes propriedades. A adsorção de moléculas de NH3 à parede dos nanotubos armchair e zigzag foi estudada onde foram investigadas as alterações nas propriedades decorrentes da adsorção, mostrando que os nanotubos de ZnO são possíveis de serem aplicados em sensores de gás amônia. Por fim, o estudo de sistemas com interface ZnO/GaN foram estudadas para as superfícies (101 ̅0) e (112 ̅0) e nanotubos armchair e zigzag. Ao final, concluiu-se que os sistemas de interface podem ser aplicados em LEDs, por exemplo, pois o controle de espessura e material pertencente à camada externa da interface leva a diferentes emissões no espectro eletromagnético, indo do UVA ao Verde. Com este estudo, pretendeu-se investigar o máximo das três morfologias do ZnO na fase wurtzita e sugerir algumas possíveis aplicações.
Computational chemistry has proved to be a very useful tool in the scientific field and has been increasingly used in the research of new materials. Among the many systems studied with the aid of computational chemistry, we highlight zinc oxide (ZnO), widely used in many electronic devices such as sensors, solar cells, UV light emitting diodes and laser diodes. At room temperature and pressure, the most stable crystalline structure of ZnO is hexagonal of the wurtzite type, in which the zinc atoms are coordinated to four oxygen atoms. Due to the tetrahedral coordination and lack of center of symmetry of this structure, the ZnO presents piezoelectric properties and can be applied in piezoelectric sensors, for example. Currently, there are many papers related to ZnO, however the number of theoretical articles in relation to the experimental works are still small. In this sense, this project aimed the analysis of ZnO properties in three different morphologies, bulk, surfaces and nanotubes, applying the main techniques of computational modeling to solid state such as the choice of density functional and basic functions, optimization of geometry, doping by atom replacement, calculation of elastic and piezoelectric constants, hydrostatic pressure simulation applied to unit cell, bulk section to generate surfaces, replacement of atoms to form interfaces, nanotubes and adsorption of molecules in nanotubes. The calculations were performed applying the Density Functional Theory, with the help of the CRYSTAL14 program, using the hybrid function B3LYP, with the set of all-electron base functions. The applied methodology preserves the periodicity of the crystalline systems (1D for nanotubes, 2D for surfaces or 3D for bulk), in which the building blocks are composed of unit cells and can be replicated by the symmetry operator. The topological reviews were performed applying the Quantum Theory of atoms in Bader's Molecules. After choosing the level of theory, the structural, electronic, vibrational, topological and elastic and piezoelectric constants were analyzed for bulk. From the optimized structure, the zinc atoms were replaced by Mn2+ and Al3+, simulating doped systems. In parallel, a study of the behavior of the elastic and piezoelectric constants was conducted due to the hydrostatic pressure variation, which showed that the piezoelectric response of ZnO increases according to the pressure. After the bulk study, the surfaces (101 ̅0), (112 ̅0) and (0001) were analyzed and studied through their surface energy, structural, electronic and topological properties. From the surface monolayer (0001), the armchair, zigzag and chiral nanotubes were generated and studied according to their obtainment, stability and different properties. The adsorption of NH3 molecules to the wall of the armchair and zigzag nanotubes was studied and an investigation of the changes in the adsorption properties was carried out, showing that ZnO nanotubes are possible to be applied in ammonia gas sensors. Finally, the study of systems with ZnO/GaN interface was conducted for the surfaces (101 ̅0) and (112 ̅0), and armchair and zigzag nanotubes. At the end, it was concluded that the interface systems can be applied in LEDs, for example, because the control of thickness and material belonging to the outer layer of the interface leads to different emissions in the electromagnetic spectrum, going from UVA to green. This study aimed to investigate the maximum of three ZnO morphologies in the wurtzite phase and to suggest some possible applications.
FAPESP: 2013/19713-7
FAPESP: 2016/07954-8
Tinel, Liselotte. "Des réactions photochimiques aux interfaces atmosphériques." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10263/document.
Повний текст джерелаThe works presented in this thesis concern firstly the characterization of two new photosensitizers by spectroscopic methods. This way the kinetics of the oxidation reaction between the triplet state of the photosensitizers, imidazole-2-carboxaldehyde and 6-carboxypterin, and three halides have been determined by laser flash photolysis. Also, the reactivity of the singlet state of 6-carboxypterin with halides and four organic acids has been studied by static fluorimetry. These photosensitizers are relevant for the photochemistry at the surface of the ocean, but also at the surface of atmospheric particles. The reactions evidenced by these studies lead to the formation of very reactive radical species influencing the composition of the condensed and gas phase of the marine environment. This study then focalized on the analysis of the products formed at the organic coated air-water interface through photo-induced processes. Two different organics were used as surfactants, octanol and nonanoic acid. In the presence of a photosensitizer and UVA light, the changes in the gas phase were monitored online by SRI-ToF-MS and in the condensed bulk phase by UPLC-(ESI)-HRMS offline analysis. These analysis showed that photochemical reactions at the interface lead to the formation of functionalized and unsaturated compounds initiated by a hydrogen abstraction on the organic surfactant. These products, observed in the condensed and gas phase have the potential to contribute to the formation of aerosols. Surprisingly, some of these products were also observed in the two phases without the presence of a photosensitizer, bringing into evidence a photochemistry of nonanoic acid at the air-water interface. Potential formation mechanisms of the products and environmental consequences are discussed
Srour, Rafif K. "Metal-surface reactions in mixed aqueous organic solvents." Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3582.
Повний текст джерелаTitle from document title page. Document formatted into pages; contains xix, 140 p. : ill. Includes abstract. Includes bibliographical references (p. 133-140).
Nunnery, Grady A. "The influence of surface curvature on polymer behavior at inorganic surfaces." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33929.
Повний текст джерелаKjellin, Mikael. "Structure-Property Relationships of Surfactants at Interfaces and Polyelectrolyte-Surfactant Aggregates." Doctoral thesis, KTH, Chemistry, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3299.
Повний текст джерелаThe first part of this thesis is concerned with thestructure-property relationships in nonionic surfactantsystems. The main aim was to investigate how the surfactantstructure influences the adsorption at interfaces andinteractions between surfactant coated interfaces.Particularly, the effect of the structure of the surfactantheadgroups was investigated. These were sugar-based headgroupwith varying size and flexibility and poly(ethylene oxide)based headgroups with or without an additional amide or estergroup. The hydrophobic part of the surfactant consisted mostlyof straight alkyl chains, except for one type of poly(ethyleneoxide) based surfactant with a dehydroabietic hydrophobe.
The main technique that was used is the surface forcetechnique, with which the forces acting between two adsorbedsurfactant layers on hydrophilic or hydrophobic surfaces can bemeasured. These forces are important for e.g. the stability ofdispersions. The hydrophilic surfaces employed were glass andmica, whereas the hydrophobic surfaces were silanized glass andhydrophobized mica. The adsorption behavior on hydrophilicsurfaces is highly dependent on the type of headgroup andsurface, whereas similar results were obtained on the two typesof hydrophobic surfaces. To better understand how the surfaceforces are affected by the surfactant structure, measurementsof adsorbed amount and theoretical mean-field latticecalculations were carried out. The results show that the sugarsurfactant layers and poly(ethylene oxide) surfactant layersgive rise to very different surface forces, but that the forcesare more similar within each group. The structure-propertyrelationships for many other physical properties have beenstudied as well. These include equilibrium and dynamicadsorption at the liquid-vapor interface, micelle size, micelledynamics, and wetting.
The second part in this thesis is about the aggregationbetween cationic polyelectrolytes and an anionic surfactant.The surface force technique was used to study the adsorption ofa low charged cationic polyelectrolyte on mica, and theaggregation between the adsorbed polyelectrolyte with theanionic surfactant. The aggregation in bulk was studied withturbidimetry, small angle neutron scattering (SANS), and smallangle x-ray scattering (SAXS). An internal hexagonal aggregatestructure was found for some of the bulk aggregates.
Keywords:nonionic surfactant, sugar surfactant,poly(ethylene oxide), amide, ester, polyelectrolyte, SDS,hydrophobic surface, glass surface, mica, adsorption,aggregation, micelle size, surface forces, wetting, dynamicsurface tension, NMR, TRFQ, SANS, SAXS, mean-field latticecalculations.
Souharce, Grégoire. "Génération de surface nanostructurées par le contrôle des interactions aux interfaces." Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00845841.
Повний текст джерелаBhattarai, Bishal. "Wetting properties of structured interfaces composed of surface-attached spherical nanoparticles." Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1544817024854422.
Повний текст джерелаJuang, Agnes Okumura Mitchio Lewis Nathan Saul. "Effects of surface modification on charge-carrier dynamics at semiconductor interfaces /." Diss., Pasadena, Calif. : California Institute of Technology, 2003. http://resolver.caltech.edu/CaltechETD:etd-08062002-192958.
Повний текст джерелаManesse, Maël. "Développement de nouvelles interfaces plasmoniques appliquées à la biodétection." Grenoble INPG, 2009. http://www.theses.fr/2009INPG0056.
Повний текст джерелаIn this research work, new interfaces adapted for surface plasmon resonance (SPR) and electrochemical studies were developed for biosensing applications. These interfaces are formed by depositing thin oxide films on Titanium/Gold (Ti/Au) substrates, classically used in SPR. Different types of hybrid interfaces were formed, such as Ti/Au/SiOx (silicon oxide), Ti/AU/SnO2:Sb (antimony doped tin oxide), and Ti/Ag/SnO2:Sb. These new interfaces were characterized by SPR,, elechemistry and X-ray photoelectron spectroscopy (XPS). Different surfaéce chemistry approaches were investigated with the aim to covalenty link biomolecules to the oxide surface. Finally, we show the possibility of forming o localized surface plasmon resonance (L-SPR) sensing platform. It is based on the integration of gold nanoparticles into a biopolymer matrix
Benusiglio, Adrien. "Indiscrétions aux interfaces." Phd thesis, Ecole Polytechnique X, 2013. http://pastel.archives-ouvertes.fr/pastel-00860739.
Повний текст джерелаMorgan, S. J. "An experimental study of the vanadium and calcium fluoride/silicon (111) interfaces." Thesis, Bucks New University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234711.
Повний текст джерелаVessely, Christina Regina. "Effects of solution parameters on the adsorption of proteins at interfaces /." Connect to full text via ProQuest. IP filtered, 2006.
Знайти повний текст джерелаTypescript. Includes bibliographical references (leaves 159-173). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;
Bourdoucen, Hadj. "Etude des surfaces d'InP et des interfaces InP-isolant par photoluminescence." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376033378.
Повний текст джерелаGuzha, Alphonce Chenjerayi. "Integrating Surface and Sub Surface Flow Models of Different Spatial and Temporal Scales Using Potential Coupling Interfaces." DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/50.
Повний текст джерелаMonga, Tanya. "Surface stress at the solid-liquid interface : alkanethiol monolayers on gold." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101628.
Повний текст джерелаBlomfield, Christopher James. "Study of surface modifications for improved selected metal (II-VI) semiconductor based devices." Thesis, Sheffield Hallam University, 1995. http://shura.shu.ac.uk/19362/.
Повний текст джерелаBouali, Bachir. "Contribution à l'étude des phénomènes de mouillage pour la caractérisation des surfaces et interfaces : maîtrise de la physico-chimie et de la morphologie des surfaces pour régler les propriétés fonctionnelles des interfaces : applications industrielles." Lyon 1, 1998. http://www.theses.fr/1998LYO10132.
Повний текст джерелаCharest, Joseph Leo. "Topographic and chemical patterning of cell-surface interfaces to influence cellular functions." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/24621.
Повний текст джерелаCommittee Chair: Dr. William P. King; Committee Member: Dr. Andres J. Garcia; Committee Member: Dr. F. Levent Degertekin; Committee Member: Dr. Hang Lu; Committee Member: Dr. Todd C. McDevitt.
Robb, David Andrew. "An investigation of the nature of the interaction of dicyandiamide cured epoxy resin adhesives with aluminium substrates, using model compounds." Thesis, University of Strathclyde, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366906.
Повний текст джерела